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403Chapter 22Towards More Open-Minded Nuclear EngineeringDiversity, Independence and Public GoodKohta Juraku© The Author(s) 2015J. Ahn et al. (eds.), Reflections on the Fukushima Daiichi Nuclear Accident ,DOI 10.1007/978-3-319-12090-4_22Abstract The implication of the PAGES project especially in Japan’s p ost- F ukushima context is examined in this chapter, summing up the arguments of sister chapters in Part IV at the same time. Social scientific literacy is not just an “additional” component for nuclear engineers. Rather, it is one of the most “essen-tial” parts of engineering competences and practices. This point has not been fully recognized, at least in the Japanese context so far. In this chapter, an epoch-making judgment by a Japanese court and the responses from nuclear engineers in Japan will be taken as a case to explore this issue. Japanese nuclear engineers misunderstood the judgment’s argument and could not make appropriate counter-arguments against the court. This kind of misunderstanding of voices from society can result both in loss of political legitimacy and stagnation in technical evolu-tion. Looking at the original nature of engineering itself, the need for fundamental change to re-establish diversity and independence in nuclear engineering, and the significance of social-scientific literacy to realize it, will be discussed.Keywords Human rights · Post-Fukushima accident · Legitimacy · Innova- tion · Diversity · Independence · Open-minded · Public good22.1 I ntroductionThis brief chapter tries to examine the implications of the PAGES project,e specially in the post-Fukushima Japanese context, summing up the arguments of sister chapters in Part IV at the same time. The PAGES project and its participants consider social scientific literacy not just as an “additional” component for nuclear K. Juraku (*)Department of Humanities and Social Sciences, School of Science and Technology for Future Life, Tokyo Denki University, 5 Senju Asahi-Cho, Adachi-ku,Tokyo 120-8551, Japane-mail: juraku@mail.dendai.ac.jp404K. Juraku engineers. Rather, it is one of the “essential” parts of engineering competences and practices. In our understanding, the importance of this perspective even becomes greater and greater, especially in this post-Fukushima nuclear scene.However, the author regrettably has to say that this perspective has not been fully and appropriately recognized by nuclear engineering experts as well as some of the other stakeholders at least in the Japanese context, though it has been over 3 years since the Fukushima Daiichi nuclear accident unfolded. In the sections below, an epoch-making judgment by a Japanese court and the responses from nuclear engineers in Japan will be taken as a case to explore this issue. Japanese nuclear engineers’ misunderstanding of the judgment’s argument will be examined critically. Then, looking at the original nature of engineering itself, the need for fundamental change in nuclear engineers’ mindset and the significance of social-scientific literacy will be discussed.22.2 D enial of Nuclear Power: A Message from JapaneseCourtOn May 21, 2014, Fukui District Court delivered a judgment about the operation of Oi Nuclear Power Plant (NPP) owned and operated by Kansai Electric Power Company. The court ordered the prohibition of operation of Units 3 and 4 of the power station, siding with a group of 189 citizens, the plaintiff. It was the first case of loss of nuclear power operator at a court since the Fukushima nuclear accident occurred.There had been several court decisions that supported nuclear opponents’ argu-ments even before the Fukushima nuclear accident, but this judgment ordered the halt of the nuclear power operation directly based on Constitutional human rights—personal rights—for the first time in Japanese legal history. The sentence points out the reality of the damage caused by the Fukushima accident and charac-terizes it as a critical threat to fundamental human rights. It says as follows: Nuclear utilization [in Japan] is limited to civilian use so that the operation of a nuclear power plant is a means of electricity production, which belongs to the freedom of eco-nomic activities [guaranteed by the Constitution], and is inferior to the core part of per-sonal rights, legally speaking. Then, it cannot be imagined that the fundamental [human] rights could be exceptionally broadly denied as much as by a nuclear accident, except fora huge natural disaster or war…. It makes sense that any commercial activities which havesuch concrete risk should be prohibited… [1].1The court clearly distinguishes the risk posed by a nuclear accident from other risks generated by general industrial activities, not by its probability but by the qualitative nature of its potential hazard (i.e., long-term radioactive contamina-tion of the environment and evacuation and damage to the community as a result). 1Translated and supplemented by the author.22 Towards More Open-Minded Nuclear Engineering405 It also determinably denies the application of cost-benefit analysis for nuclear risk through very strong criticism.The court thinks that we are not allowed to participate in nor decide something about the discussion that compares the rights of many people to their life itself to the cost of elec-tricity production… There is a discussion about outflow or loss of national wealth as regards this cost issue; we should not consider the huge trade deficit generated by the halt of the operation of these nuclear power stations as outflow nor as loss of national wealth.National wealth consists of productive land and people’s life upon that land, thus the court thinks that irreparable damage of the national land is loss of national wealth [1].2In other words, this judgment argues that our society can no longer allow the existence of nuclear power utilization (at least in Japan, thinking about its narrow national territory and density of population). It is not the health effect of radiation exposure to the public that is the central problem of the risk of a nuclear accident, but the disastrous effect on people’s life, according to their formulation. It points out that what happened and is happening in Fukushima is clear evidence and this fact validates their understanding. This is an extraordinary fundamental criticism of nuclear power technology and its utilization.22.3 R esponses from Nuclear Engineers in JapanThis radical message by the court promptly attracted strong attention from nuclear engineers in Japan, as well as from other stakeholders and citizens. Almost all responses from nuclear experts were vivid criticism, or even outrage, against the decision. They found many faults among the technical descriptions in the judg-ment and concluded the decision had serious deficits because of “misunderstand-ing” about the upgraded safety measures of the Oi NPP.The Atomic Energy Society of Japan (AESJ), the most comprehensive profes-sional and academic body in the nuclear field in Japan and the counterpart to the American Nuclear Society (ANS), published their press release about the court’s judgment on May 27 and strictly criticized it because “it might cause serious mis-understanding among people about improved safety measures at the nuclear power plant”3 [2]. It accuses the court’s formulation of the problem as “an opinion that calls for ‘zero risk’” and as “not appropriate as the legal decision by court.” It crit-icizes the court their denial of “engineering safety” because it is accepted in “almost all fields of science and technology” and “it is unfair that the court does not accept it for nuclear power stations though they should be impartial.”It also argues that another Fukushima-class nuclear accident is preventable by implementation of appropriate counter-tsunami, anti-severe-accident, and disaster prevention measures so that it would not violate personal rights.2Translated and supplemented by the author.3Translated by the author. The following quotations are also.406K. Juraku Many nuclear experts showed quite similar opinions in newspapers, on the web, and in other media. It was an “unscientific” or even “anti-scientific” challenge from a legal expert—the Chief Judge of the Fukui District Court—who doesn’t have sufficient and appropriate technological expertise. Conservative newspa-pers (Yomiuri, Nikkei and Sankei newspapers) also published their editorials and extend their support to such opinions [3–5], while their liberal counterparts (Asahi, Mainichi and Tokyo newspapers) admired the court’s decision [6–8].However, such criticisms themselves contain many “misunderstandings.” For example, AESJ’s press release criticizes the denial of the nuclear risk by the court as “zero-risk” oriented thinking but it is not the case. The judgment distinguishes the nuclear risk by its nature and the scale of hazard potential, not by its probabil-ity or so-called “death-ratio” as the author introduced earlier. It never naively calls for “zero-risk.” Rather, it questions the destructive nature of nuclear risk itself in terms of qualitative considerations.Also, some arguments cited judicial precedent sentenced by the Supreme Court about the appropriateness of the safety review of nuclear facilities and point out the contradiction between it and this judgment, but it is also incorrect.4 The former one was an administrative lawsuit so that the court reviewed the legality of the safety review, but this case was a civil case about human-rights violation. These two types of lawsuits have different nature and the points in dispute are also differ-ent. Therefore the judgments can be legitimated by different logics. The later judg-ment carefully clarifies the differences of the jurisdictions before it comes to the detailed considerations of the illegalness of the NPP operation in terms of the con-stitutional human-rights violation.The critics of the decision by the Fukui District Court seems to misunderstand, or at least not to read the sentence carefully, before they expressed their outrage against the legally powerful and fundamental denial of nuclear power utilization. Why could not they catch the point raised by the Court? Why did they show such reaction against the decision?22.4 D on’t Refuse, but Inspired by the Voice from SocietyAs Sunderland points out in Chap. 18, the problems centering around the nuclear power utilization “are not amenable to engineering’s traditional utilitarian reason-ing and optimization studies” in Post-Fukushima era [9]. However, the outraged experts seemed not to recognize this important and irreversible change. As she 4Ikata NPP (owned and operated by Shikoku Electric Company) safety review case is cited in their arguments. This was the first case of a lawsuit that dealt with the legality of the national Governmental safety review for commercial nuclear power stations. In that case, the Supreme Court of Japan established their criteria on the legality of safety review. It admitted relatively broad administrative discretionary powers on each case for governmental ministries and agencies and limited their jurisdiction to the appropriateness of the process of safety review.22 Towards More Open-Minded Nuclear Engineering407 argues, “one of the core issues with the problems surrounding Fukushima is that the answers rely on more than numbers” [9]. Fukui District Court’s critical point is tightly connected to this notion. In fact, the discussions in our Summer School covered this issue and “much time was devoted to searching for ways that nuclear power could be justified without weighing its costs and benefits in numerical terms” [9].It is regrettable that the mainstream Japanese nuclear engineers still refuse this change and look aside from the crisis of “legitimacy” as Oda concerns about it in his chapter [10]. They have seemed to be stubbornly attached to defend the “cur-rent” nuclear system and its logic of safety and to try to make the world friendlier to them. There have been no alternative ideas to safety improvement of the cur-rent nuclear fleet by so-called backfitting and to increase emergency preparedness explicitly suggested by the Japanese nuclear engineering community. They have been eager to ‘explain’ those improvements but reluctant to do something funda-mentally different with their past practices.However, if the expert community interpreted the voices from society more sensitively and humbly, they could suggest much more drastically different answer to make nuclear power technology more preferable for society, in the author’s opinion. For example, they could suggest clear commitment to dry-cask storage system of spent fuel with passive safety feature to substantially decrease the risk of spent fuel management. The court’s judgment points out the vulnerability of barriers of spent fuel pool and considers it as one of the most contributory sources of possible massive radioactive release. Their critical criterion of risk acceptance is the scale of potential hazard so that the inventory of nuclear fuels is the most critical factor to discuss nuclear safety. This safety improvement should have much bigger impact on Judge’s impression about the efforts by the nuclear com-munity than a set of ‘explanations’ of sufficiency of current safety measures.Also, some nuclear engineers could have suggested the introduction of so-called small- and medium-sized reactors (SMRs), instead of huge 1 GWe class power plant, which have been the mainstream in Japanese nuclear power utilization. If we think about the issue of inventory of radioactive materials on each site and the dis-cussion on the promotion of renewable energy utilization and the shift to more dis-tributed power system, we can understand the advantages of SMRs technology. Of course, it is unclear whether the society successfully would accept these ideas and would agree to continue the nuclear power program with improved risk manage-ment and compatibility with distributed power system. There seems to be a great deal of possibility that people say “no” even if nuclear engineers suggest such ideas.However, the most important thing here is not the result of such suggestions, but the spontaneous efforts by nuclear engineers to be “introspective” themselves as both of Sunderland and Oda argue [9, 10]. People can think about the substan-tial difference between the efforts to defend their legacy by some ‘explanations’ and to overcome the failure by their wisdoms and innovations. It should have totally different impact on the people’s respect for their nuclear engineers regard-less of the appropriateness of the policies and behaviors by the Government and other responsible organizations (such as TEPCO).408K. Juraku Nuclear engineers should not refuse the questions and criticisms from the other members of society, but should listen to them carefully, think about the i mplications for them deeply and response to them sincerely in proactive manner.22.5 D emocratization of Nuclear Engineering:Not Just for Political Correctness, but Alsofor Innovation of TechnologyAs Bollerri discusses, nuclear technology is not a market-oriented enterprise. It has been strongly committed and controlled by the governments so that “there is a lack of experience with direct interaction between the nuclear engineer and the public” [11]. He also mentions about the consequences of this “detachment from their ‘client’” as follows:This has led many times to an ‘us versus them’ mentality which only fosters antagonism.This has historically shown to be the wrong approach. This can occur when so-called ‘technocrats,’ while well intentioned, try to make decisions based solely on science and engineering by relying on a responsibility for ‘good of the public,’ without experiencing or communicating directly the public, whom these decisions affect [11].What the author discussed in the previous sections can be interpreted as a case of this phenomenon. Historically speaking, Science and Technology Studies (STS), Sociology of Science and Technology and History of Science and Technology have critically examined such mechanism motivated by the improvement of politi-cal legitimacy and the democratization of science and technology. In other word, they have problematized this issue for the sake of the other members of society, not for engineers. However, the author would like to argue that this situation is critically problematic not only for the rest of society, but also for engineers them-selves at the same time, when we think about the future of (nuclear) engineering in society.Achievement of engineering is not limited to improvement of technology. Innovation of technology should also be, or sometimes more, important and excit-ing for engineers. Of course, improvement also requires substantial innovation in many cases. But, what is really admired by their colleagues and ‘clients’ is the epoch-making breakthrough that provides brand-new options for society.This kind of innovation is sometimes not a direct evolution of preceding tech-nology and its appraisal. Christensen sheds new light on mechanism of innova-tion by examining many cases of “disruptive innovations” in his famous book The Innovator’s Dilemma [12]. He emphasizes the importance to be free from stereo-typical, conservative mindsets that prevent such breakthrough. It should be noted that experts tend to be possessed by conventional appraisal standard of technical merits. Sony’s engineers could not change their goal for the best portable audio player from its sound quality, battery life and compact body to something another. Their product—the Walkman—had monopolized the market in the past, but their22 Towards More Open-Minded Nuclear Engineering409 position was suddenly replaced by a new comer with the huge storage capacity–Apple’s iPod, although it was not superior to Walkman in terms of the conven-tional advantages listed above. Apple’s engineers were free from the traditional belief in the business, found a potential need in the market—to bring personal jukebox—and realized it by existing technical components. As Sony’s engineers, nuclear engineers who cannot free from the traditional belief—bigger output for centralized power distribution system and conventional cost-benefit analysis—could be left by their ‘client’ in the Post-Fukushima society. Rapid promotion of renewable energy and liberalization of power industry is inevitably and irrevers-ibly being carried out now, though Japanese national policy has not chosen the clear commitment to rapid phase-out from nuclear power so far. If nuclear engi-neers could not provide any suitable nuclear power system that is nicely compat-ible with distributed power system provided by renewable power sources, they might not be able to keep their presence both in energy technology field and in society.If Japanese nuclear engineers had understood this need and another need for intrinsic safety, which was discussed in the previous section, more rapidly and precisely, some of them might have suggested different nuclear power system with SMRs for society, not just to say something about the safety improvements of the existing large-scale NPPs across Japan. It is not necessary that every engi-neer defends the appropriateness and advantages of current nuclear power system and supports the Governmental and the utility companies’ policy of nuclear power utilization. However, there have been only a few fundamentally different propos-als of nuclear power utilization for Post-Fukushima era so far. Almost no engi-neer is trying to change such a big picture at least in Japan. This is quite unnatural and unsound situation when we think about the competitive nature of engineering practices.22.6 C oncluding Remarks: Independence and Diversityof Nuclear Engineering for Unprecedented ChallengeEngineering is inherently dynamic activity. Many engineers are doing their works under competitive circumstances and love it. Difference makes advantages. Diversity motivates technological evolution. As the author cited Christensen’s analysis above, so-called the B to C (Business to Consumer) fields, such as con-sumer appliances business, have such a nature in fact. However, nuclear technol-ogy is unfortunately much more “national capitalistic” because of its technical nature and historical origin [13]. Furthermore, the power utility business also has bureaucratic constitution because it is a vital infrastructure system and never allowed to make any serious failure. These factors make the mindset of the mem-bers of “nuclear village” more and more conservative and closed-minded. These characteristics of nuclear industry and policy-making system have created a410K. Juraku path-dependent, failure trajectory and resulted in the occurrence of “structural dis-aster,” as Matsumoto discussed in Chap. 10 [14].However, as briefly illustrated in this chapter, what society requests to engi-neers is being changed fundamentally now. This change had been unfolded even before the Fukushima Accident happened, but both of magnitude and velocity of it has been even increased so much in this Post-Fukushima society. If nuclear engineers don’t listen to people’s voice, don’t change their thinking, don’t suggest alternative picture of nuclear utilization for society, the future of nuclear technol-ogy could never be positive one. What people would like to have is never inten-tionally unified, stereotypical answer that suggests the existence of bureaucratic control on the nuclear engineering community. But, citizens and all other stake-holders desire to have more diversified and organized options that have been elab-orated through unfettered discussion and sincere efforts by independent engineers. They are waiting for the nuclear engineers to break their fetters of “nuclear vil-lage”. As Borrelli argues, we need ‘third generation’ nuclear engineers “that will lead and shape perspectives on nuclear technology and develop new relationships with society” [11].It is the era of unprecedented challenges in nuclear field. Innovation in nuclear power system, treatment of contaminated environment by the Fukushima Accident, decommission of damaged Fukushima plants, management of various kinds of radioactive wastes, almost all contemporary challenges in the nuclear field have no established paradigm or concrete model-cases. It’s not the era of “long-term plan” set by the Government as the rock-ribbed law. Most of them are not just technically solvable in the sense of conventional engineering practices. They “rely on more than numbers” [9].Social-scientific literacy is not a tool to manipulate public sentiment, rejecting their voices. It is a method to listen to it carefully, to find and grasp needs in soci-ety, to suggest engineers’ proposal to society in humble and sincere manner and to collaborate with other stakeholders than nuclear engineers’ ‘old friends.’ Engineers can take its advantages to make their thoughts and practices more open-minded ones as discussed in this chapter. It can become a strong tool to break their fetters, of course.Return of diversified and independent nuclear engineers is now being waited by society.Open Access This chapter is distributed under the terms of the Creative Commons Attribution Noncommercial License, which permits any noncommercial use, distribution, and reproduction in any medium, provided the original author(s) and source are credited.22 Towards More Open-Minded Nuclear Engineering411 References1. Fukui District Court (21 May 2014) Judgment, Case (wa) No.394 (2012) and Case (wa)No.63 (2013)2. Atomic Energy Society of Japan (27 May 2014) Statement for the juridical decision of pro-hibition of Oi nuclear power station units 3 and 4 operation. Available via AESJ website http://www.aesj.or.jp/info/pressrelease/PR20140527.pdf. Accessed 20 July 20143. Yomiuri Newspaper (22 May 2014) Editorial: Oi restart case: Denial judgment led by unrea-sonable reasoning4. The Nikkei (23 May 2014) Editorial: Questions for the Oi prohibition judgment5. Sankei Shimbun (23 May 2014) Editorial: Restart of Oi was refused: Unscientific and unreal-istic judment6. Asahi Shimbun (22 May 2014) Editorial: Oi prohibition judgment: It cannot be ‘Neglected’7. Mainichi Shimbun (22 May 2014) Editorial: Prohibition of Oi NPP: Warning for restart with-out debate8. Tokyo Shimbun (22 May 2014) Editorial: Oi prohibition case: A judgment to protect people’slife9. Sunderland M (2014) Educating the Post-Fukushima Nuclear Engineer. In: this volume,Chapter 1810. Oda T (2014) Nuclear engineers for society: What education can do. In: this volume, Chapter2011. Borrelli RA (2014) Reflections on developing an identity for the third generation nuclearengineer in the post-Fukushima society. In: this volume, Chapter 1912. Christensen CM (1997) The innovator’s dilemma: When new technologies cause great firmsto fail. Harvard Business School Press, Boston13. Yoshioka H (1999/2011) Shin-ban genshi-ryoku no shakai-shi: Sono nihon-teki-tenkai.Social History of Nuclear Power: The Trajectory in Japan (2nd ed.). Asahi-shimbun Shuppan, Tokyo14. Matsumoto M (2014) The “structural disaster” of the science-technology-society interface:From a comparative perspective with a prewar accident. In: this volume, Chapter 10。

涉外秘书 Unit 4

Part 1
Part 2
Part 3
Part 4
Part 5
Dialogues
Dialogue One
H: briefly checking the letter and then signing it, Fine. Could you make three copies, please1? S: Three copies. H: Yes. Send one to the president, one to marketing, and keep one on file please2. S: Okay. H: Oh, And send the original by express mail3.
Practical English Course for Foreign-oriented Secretary
Unit 4
Communicating with Your Boss
Study Objectives
掌握秘书与上司用英语沟通的基本技巧
了解上司的工作指令和意图的基本方法
掌握商务场合介绍和问候的礼仪掌握英文产品说明书及广告的写法
1. ,好吗? 2. 请将它复制三份 3. 一份给总裁快件 ,快递 ,一份给营销部 ,一份存档｡
Part 1
Part 2
Part 3
Part 4
Part 5
Dialogues
Dialogue One
S: Do you think it is too late if I mail the parcel after work when I am on my way home? H: I don’t think so. But I hope it can reach London as soon as possible. S: I see, I’ll do that right now. (turning to leave) H: (remembering something) Oh, Before that, could you get me the sales figures for last month, please? S: Sure.

English_the_Berlitz_Way_Unit4

English the Berlitz WayLevel 1Lesson 1:Unit 4: The City 城市声音文件:D2.13Page sixty-oneThere’s a bank on the corner.如何描述建筑物或地方的位置Excuse me, is there a drugstore near here?Excuse me, is there a bank near here?Excuse me, is there a hospital near here?Excuse me, is there a mailbox near here?Activity one page sixty-twoExcuse me.Yeah?Is there a post office near here?Sorry, I don’t know. I don’t live here.Oh, I see. Sorry.Excuse me.Yes, Can I help you?Yes, please.Is there a post office near here?Yes, there is.There’s one next to the Grand Hotel.Sorry?Do you see that Italian restaurant over there?What restaurant?Next to the travel agency.Do you see that?Oh, on the corner?Yes, on the corner.Well, the Grand Hotel is just around the corner, and there’s a post office next to it.Thank you. Thank you very much.You’re welcome.There’s one next to the Grand Hotel.There’s one across from the Grand Hotel.Excuse me, is there a bank near here?Yes, there’s one on the next block.There’s one on the next corner.声音文件:D2.14Activity two page sixty-two1.oneCan I help you?Thanks, is there a bank near here?Yes, there’s one on the next block.It’s next to a French restaurant.Thanks.2.twoExcuse me, is there a gas station near here?Umm, let me see.Do you see that big white building over there?Yes.Well, that’s a supermarket, and there’s a gas station right across from it, on the corner.Thank you.That’s ok.3.threeExcuse me.Sure. Can I help you?Yes, please. Is there a drugstore near here?Uh, yes.There’s one on the next block, next to the theater.Do you see the Palace Theater?Yes, I see it.Well, there’s a drugstore right next to it.Thanks.You’re welcome.Is there a bus stop near here?Yes, there’s one in front of the drugstore.There’s one in front of the drugstore.There’s one near the theater.On the right.There’s one on the next block on the right.On the left.There’s one on the next block on the left.Where’s the …Excuse me, where’s the Ritz Hotel?It’s that a large black building over there.Excuse me, where’s the Palace Theater?Excuse me, where’s the City Hospital?Excuse me, where’s the restaurant?It’s on the first floor.Excuse me, where’re the men’s shoes?They’re on the third floor.First[fə:st] second['sekənd] third[θɜ:d] fourth[fɔ:θ, fəʊrθ] fifth[fɪfθ] sixth[sɪksθ] seventh['sevənθ] eighth[eɪtθ, eɪθ] ninth[naɪnθ] tenth[tenθ] Good morning, can I help you?Oh, yes.Where’re the children’s clothes?Children clothes are on the fourth floor.Fourth floor, thank you.Excuse me, do you have a coffee shop?Yes, we’re do.The coffee shop are on the second floor.Thanks.Good morning.Oh, good morning.Where’re the watches, please?The watches are on the fifth floor.Thank you.Excuse me?Yes, sir.Can I help you?Yes, please.Where’s Mr. Carter office?The personal manager.Yes, that’s right.He’s office on seventh floor.Could I have you name, please?Yes, it’s Grant, Stephen Grant.声音文件:D2.15Activity six page sixty-fiveI have a really nice apartment.The apartment building is on Forest Road and I live on the fourth floor. There’s a park right across the street.There are lots of small shops too.And there’s a good Italian restaurant just on the corner.Oh, yes.And there’s a bus stop just in front of our building.声音文件:D2.16Page sixty-sixTake the second left.如何询问和辨别方向How do I get to …?Excuse me, how do I get to Forest Road?Macey’s department store.Excuse me, how do I get to Macey’s department store?Excuse me, how do I get to Colombia University?Can you tell me how to get to …?Can you tell me how to get to Colombia University?Can you tell me how to get to City hospital?Turn right at the corner.Turn left at the corner.Traffic light.Turn right at the traffic light.Take the second left.Take the third left.Take the second left.Take the first right.Go straight ahead …Go straight ahead for two blocks.Activity one page sixty-six1.oneExcuse me, how do I get to the ABC Theater?The ABC? OK, do you see those traffic lights?Turn left there, and then take the second right.The theater’s about tow blocks down, on your right.Thanks.You’re welcome.2.twoExcuse me, how do I get to Grand Central Station from here?I’m sorry, I don’t know. I’m lost!Oh, I see.Thanks anyway.Excuse me, can you tell me how to get to Grand Central Station? Sure. Go straight ahead for … let me see …three blocks, no two blocks, straight ahead for two blocks, then turn right.Go straight ahead for five or six blocks after that, and it’s on your right. Thanks a lot.声音文件:D2.17Activity two page sixty-seven1.oneThe bus station?Sure.See the black building on the right?Turn right just there, and then take the … one, two, three, take the third left.There’s the hotel on the corner.Go straight ahead and the bus station is on the left.It’s across from a small park.2.twoSure.There’s a post office near here.Do you see the movie theater over there?Turn right there, then take the second left.There’s a post office next to the Grand Hotel.3.threeYes, I know Forest Road.My friend lives there.Well, go straight ahead for three blocks, then turn left at lights.Go straight ahead, and take the second right.There’s a school on the corner on the left.But turn right there.Then take first right, and that’s Forest Road.It’s that OK?Go up the hill.Go down the hill.Go over the bridge.Go under the bridge.Go to the park.Go past the Grand Hotel, and past the small park, and then turn left. Don’t turn right.Don’t go to the park.Don’t go under the bridge.Don’t take the first left.Don’t stop here.声音文件:D2.18Activity five page sixty-eightNow let me see.Where are we?Ah, yes.Turn left there.Here?No, don’t turn left here!There, at the lights.Turn left at the lights.Sorry, dear.Now, go straight ahead for a few blocks.Where’s the bridge?Is there a bridge?Ah, yes.There it is.Go over the bridge and past a school.Where’s the school?There! There’s the school.On the right.Thank you, David.I see the school.Please be quiet.What do I do next?Do I go straight ahead up the hill?Just a moment.Yes, that’s right.Up the hill.Then take the second right.No, don’t turn right here!The second right!The second right at the lights.Yes, and then we go through the park, turn right, go past the post office, and then there’s the … oh where’s the hotel?Where are we?We’re lost!Then turn left at eighty-six street.Sorry, turn left where?At eighty-six street.There’s the theater on the left, and there’s a bus stop in front of the theater.Sorry, and where in front of the theater?There’s a bus stop in front of the theater.Go straight ahead for two blocks, go past the City Hospital, and then …I’m sorry!Go past where?Past the City Hospital.Go straight for two blocks, and then turn right, at the large black office building.Sorry, turn right where?At the large black office building.Tack the second left, there’s a small Japanese restaurant there on the corner.Sorry, there’s a where on the corner?A small Japanese restaurant.声音文件:D2.19Page sixty-nineWhat time do you close?如何询问营业时间Days of the week 星期中每一天的名称:Monday['mʌndi] Tuesday['tju:zdi] Wednesday['wenzdi] Thursday['θə:zdi] Friday['fraidi] Saturday['sætədi] Sunday['sʌndi]Activity one page sixty-nine1.oneTaylor Sports Shop.Can I help you?Yes, please.Are you open tomorrow?No, I’m sorry Madam.It’s Sunday tomorrow, so we’re closed.We’re closed on Sunday and Monday.And Monday? Oh I see.Thank you.2.twoExcuse me, what days are you closed?The pool is open every day, but on Wednesdays and Thursdays it’s closed in the evenings.Thanks.3.threeAre the post office open on the weekends?No, they’re closed on Saturday afternoons and Sundays.Oh, dear.Are you open tomorrow?What days are you close?Are the post office open on the weekends?What time do you close?What time do you open?What are your hours?We’re open at nine ten.We’re closed at five fifteen.We’re open at eight fifty.And we’re closed at six twenty.We’re open at six forty-five.We’re closed at eleven fifteen.声音文件:D2.20Activity two pages seventy1.oneExcuse me, what are your hours, please?We’re open from six-thirty to eleven forty-five.Eleven forty-five.Thank you.You’re welcome.2.twoCan I help you?Yes, what time do you close today, please? At six fifteen.We’re open until six fifteen. Thanks.3.threeHello, hello.I’m sorry, we’re closed.Yes, I know.But time do you open this evening, please? We’re open at eight twenty.Eight twenty until 2 (two) A.M.Right. Thanks.We’re open at nine-thirty.We’re closed at five o’clock.We’re open on Saturday.But we’re closed on Sunday.It’s two-ten.It’s ten past two.It’s ten after two.It’s two-forty.It’s twenty to three.QuarterIt’s four fifteen.It’s quarter past four.It’s four forty-five.It’s quarter the five. (4:45)声音文件:D2.21Activity three pages seventyGood afternoon, madam.Can I help you?Yes, please.I have some questions about the hours of these places.OK. Go ahead.Uh, first the flea market.The flea market is only open on Sundays.Oh, I see.From what time?From ten A.M. to five-thirty.Five-thirty.Ok. And the Empire State Building?Is it open every day?Yes, it is.It’s open from nine-thirty until twelve o’clock midnight every day. Now, the bus tour.The Bronx Zoo tour, what day is that?The Zoo tour is only on Saturdays, from nine A.M to four P.M.Only on Saturday?That’s no good.What’s this?The beautiful Bronx bus tour.What day is that?The beautiful Bronx bus tour is on Tuesdays, Wednesdays, and Thursdays from 8(eight) A.M. to 1(one) o’clock.Eight to one Tuesday, Wednesday, and Thursday.That’s good!How much is it?It’s twenty-five dollars per person.OK, thanks.声音文件:D2.22Pages seventy-one PronunciationPronunciation[prəˌnʌnsiˌeiʃən] (一种语言的)发音(法) activity one page seventy-one1.oneTurn left at the corner.2.twoGo over the bridge.3.threeTake the first street on the right. 4.fourWe open at nine o’clock.5.fiveThere’s a bank on the left.No, there’s a bank on the left.No, there’s a bank on the left.Pronunciation activity two page seventy-one1.oneWe’re closed on Sundays and Mondays.2.twoIt’s not on the left, it’s on the right.3.threeDon’t go through the park.4.fourThe watches are on the fourth floor.5.fiveExcuse me, what time do you close?。

大学英语2第七单元ppt课件

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谢谢
THANKS
Historical Context
Slang and Colloquialisms
The text incorporates several American slang terms and colloquialisms that give it a unique cultural flavor. For example, the characters use phrases like "Let's grab a bite to eat" or "He's a real uptown guy."
Content Value
The unit's content was highly relevant to real-world situations, making it engaging and useful for students.
Future Improvements
For future units, more practice opportunities and additional support for language complexities would be beneficial for student learning.
Literary style: Realism, regionalism
Name: John Smith
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Publication date: 1925
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Title: "The Great Gatsby"
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Author: F. Scott Fitzgerald

brooks

L EGAL U NCERTAINTY,E CONOMICE FFICIENCY, AND THE P RELIMINARYI NJUNCTION D OCTRINERichard R.W. Brooks* and Warren F. Schwartz**I NTRODUCTION (382)I.A RTICULATED S TANDARDS FOR P RELIMINARY I NJUNCTIONS (388)A. Traditional Approaches (389)B. The Error-Minimizing Leubsdorf-Posner Formulation (390)C. Our Alternative Formulation (393)II.M ODEL AND A NALYSIS (394)A. The Leubsdorf-Posner Formulation of the Traditional BalancingRule (396)B. If Preliminary Injunctions Were Never Available (397)1. Incentives when compensation is provided for nonobligatoryperformance (398)2. Incentives when there is no compensation for nonobligatoryperformance (399)C. If Preliminary Injunctions Were Always Available (399)1. Incentives when compensation is provided for nonobligatoryperformance (400)2. Incentives when there is no compensation for nonobligatoryperformance (401)D. Implications: An Asymmetry in Substantive Law (401)III.W HICH R ULE S HOULD B E E MPLOYED? (402)A. Interim-Efficiency Rule (403)B. Preliminary Injunction Liability Rule (405)C. Error-Minimizing Rule in Practice (407)C ONCLUSION (409)*Associate Professor, Yale Law School.**Professor Emeritus of Law, Georgetown University Law Center. We thank Bruce Ackerman, Ian Ayres, Bill Eskridge, Owen Fiss, John Langbein, Eric Posner, Judith Resnik, Alan Sykes, and participants at Georgetown and Northwestern workshops. Sabrina Charles and Albert Wang provided outstanding research assistance.38158:381382 STANFORD LAW REVIEW [Vol.I NTRODUCTIONIn this Article, we consider preliminary injunctions from a radically different perspective than that articulated in judicial opinions and prior legal scholarship. By conventional accounts, when confronted with uncertain legal entitlements, courts should consider preliminary awards only if adequate compensatory remedies are unavailable. The trouble with this “compensatory”view is that it is unresponsive to the ex ante behavioral consequences of legal uncertainty. When rights are uncertain, parties appreciate the full benefits oftheir conduct, but they discount harm to others of this conduct by the likelihoodthat they possess a legal entitlement to so act. Hence, individual incentives to behave efficiently are distorted by uncertain legal entitlements. Preliminary injunctions correct this distortion by wielding a stick and providing a carrot fora defendant who would otherwise discount damages given some positive probability that she may not have to pay them. The powerful stick in this example is the in terrorem damages that defendant will be required to pay if an injunction is granted and she violates it. The carrot is the reimbursement of compliance costs if defendant prevails at the end of the litigation. These penalties and rewards come into play only if the plaintiff decides to pursue the injunction, which is to say that the preliminary injunction doctrine takes the conduct decision out of the hands of the biased defendant and places it in the hands of plaintiff who, by design, faces the proper marginal costs and benefitsof the decision. Interestingly, although courts do not claim that they are promoting efficient behavior when granting preliminary injunctions, that characterization represents a good account for much of what courts are doing.Preliminary injunctions are broadly used. Parties seek injunctions to enjoin patent, copyright, and trademark infringement,1 corporate mergers,2 breaches1.See, e.g., SunTrust Bank v. Houghton Mifflin Co., 268 F.3d 1257 (11th Cir. 2001) (vacating an order granting a preliminary injunction to the owners of copyright in the novelGone with the Wind,which had enjoined the publication and distribution of The Wind Done Gone); Ty, Inc. v. Jones Group, Inc., 237 F.3d 891 (7th Cir. 2001) (affirming grant of preliminary injunction in trademark infringement case relating to Ty’s Beanie Babies toys);CNB Fin. Corp. v. CNB Cmty. Bank, No. CIV.A.03-6945(PBT), 2004 WL 2434878 (E.D.Pa. Sept. 30, 2004) (enjoining defendant from trademark infringement); Best Cellars, Inc. v.Grape Finds at Dupont, Inc., 90 F. Supp. 2d 431 (S.D.N.Y. 2000) (enjoining defendants fromtrade dress infringement and copyright infringement); Progressive Games, Inc. v. Shuffle Master, Inc., 69 F. Supp. 2d 1276 (D. Nev. 1999) (granting preliminary injunction in gambling machine patent infringement case).2.See, e.g., Mony Group, Inc. v. Highfields Capital Mgmt., L.P., 368 F.3d 138 (2d Cir. 2004) (enjoining dissenting shareholders from mailing proxy cards); Bernard v. Air LinePilots Ass’n, Int’l, 873 F.2d 213 (9th Cir. 1989) (granting injunction to set aside labor agreement); United States v. UPM-Kymmene Oyj, 2003-2 Trade Cas. (CCH) ¶ 74,101 (N.D.Ill. 2003) (enjoining merger as violative of the Clayton Act, 15 U.S.C. § 12 (2000)); In rePure Res., Inc., S’holder Litig., 808 A.2d 421 (Del. Ch. 2002) (enjoining exchange offer pending alteration of terms); Solar Cells, Inc. v. True N. Partners, L.L.C., C.A. No. 19477,2002 LEXIS 38 (Del. Ch. Apr. 25, 2002) (enjoining merger).November 2005] THE PRELIMINARY INJUNCTION DOCTRINE 383 of contract,3 nuisances,4 marriages,5entertainment,6 and even manner of dress.7 In fact, almost any activity one can imagine is potentially subject to legal restraint through preliminary proceedings.8 However, remarkably little attention has been paid to whether these proceedings tend to promote or discourage desirable activities. The neglect of this issue among law and economics scholars is particularly difficult to explain.9 The doctrine specifying when a court will grant a preliminary injunction is cast in terms with obvious economic content. The preliminary injunction is only to be granted if plaintiff will suffer significant harm and stands to recover inadequate damages if she prevails at the conclusion of the case. Moreover, the right to a preliminary injunction depends in large part (under all versions of the controlling rule) on3.See, e.g.,Arch Pers. Care Prods., L.P. v. Malmstrom, 90 Fed. Appx. 17 (3d Cir. 2003) (affirming order enforcing a noncompetition agreement); Northwest Bakery Distribs., Inc. v. George Weston Bakeries Distribution, Inc., No. 04-C8233, 2005 U.S. Dist. LEXIS 385 (N.D. Ill. Jan. 11, 2005) (allowing injunction to stop termination of bakery distribution agreement); Hillard v. Guidant Corp., 37 F. Supp. 2d 379 (M.D. Pa. 1999) (enjoining defendant from breaking exclusive sales contract); V.I. Taxi Ass’n v. V.I. Port Auth., 36 V.I.43 (1997) (enjoining defendants from violating a taxi-franchise agreement).4.See, e.g., City of S. Pasadena v. Slater, 56 F. Supp. 2d 1106 (C.D. Cal. 1999) (enjoining freeway extension); Bragg v. Robertson, 54 F. Supp. 2d 635 (S.D. W. Va. 1999) (enjoining issuance of mining permits); United States v. Power Eng’g Co., 10 F. Supp. 2d 1145 (D. Colo. 1998) (directing defendant to comply with state regulations for hazardous-waste facilities); Maloof v. State Dep’t of Env’t, 136 Md. App. 682 (Ct. Spec. App. 2001) (affirming circuit court’s issuance of preliminary injunction enjoining operation of landfill).5.See, e.g., Largess v. Supreme Judicial Court, 317 F. Supp. 2d 77 (D. Mass. 2004).6.See, e.g., Elvis Presley Enters. v. Passport Video, 349 F.3d 622 (9th Cir. 2003) (enjoining use of video clips); Video Pipeline, Inc. v. Buena Vista Home Entm’t, Inc., 342 F.3d 191 (3d Cir. 2003) (enjoining use of movie clip previews on the Internet); A&M Records, Inc. v. Napster, Inc., 239 F.3d 1004 (9th Cir. 2001) (challenging sharing and copying of music MP3 files); ABKCO Music, Inc. v. Stellar Records, Inc., 96 F.3d 60 (2d Cir. 1996) (enjoining copyright infringement by karaoke company); EMI Latin v. Bautista, No. 03 Civ. 0947 (WHP), 2003 U.S. Dist. LEXIS 2612 (S.D.N.Y. Feb. 24, 2003) (enjoining defendant from interfering with plaintiff’s rights to manufacture and distribute music album).7.See, e.g., Newsom v. Albemarle County Sch. Bd., 354 F.3d 249 (4th Cir. 2003) (using injunction to prevent the enforcement of a high school dress code); Luckette v. Lewis, 883 F. Supp. 471 (D. Ariz. 1995) (seeking preliminary injunction against a prison policy that prohibited the plaintiff from wearing colors thought to be associated with particular gangs).8.Preliminary injunctions have recently been sought in other areas, including preventing executions. In Germany v. United States, 526 U.S. 111 (1999), Germany sought a preliminary injunction to prevent the scheduled execution of one of its citizens in Arizona. See also Ozmint v. Hill, 541 U.S. 929 (2004) (granting application to vacate preliminary injunction of execution). Preliminary injunctions have also been used to prevent religious celebrations, Chabad of S. Ohio v. City of Cincinnati, 363 F.3d 427 (6th Cir. 2004), and to challenge courthouse and classroom postings of the Ten Commandments. ACLU of Ky. v. McCreary County, 354 F.3d 438 (6th Cir. 2003), aff’d, 125 S. Ct. 2722 (2005).9.There have been some efficiency considerations of preliminary injunctions in the context of intellectual property cases, but these works have not explored the efficiency of the standard per se. See, e.g., Jean O. Lanjouw & Josh Lerner, Tilting the Table? The Use of Preliminary Injunctions, 44 J.L.&E CON. 573 (2001); Mark A. Lemley & Eugene Volokh, Freedom of Speech and Injunctions in Intellectual Property Cases, 48 D UKE L.J. 147 (1998).58:381384 STANFORD LAW REVIEW [Vol. the probability that plaintiff will prevail if the case is litigated to a conclusion. These requirements seem, unmistakably, to represent an attempt to adapt efficiently to the uncertainty of the final outcome. In commonsense terms, thereis a prevailing awareness that the requisite tasks to achieve the objectives of the controlling legal rule cannot be deferred until the conclusion of the litigation.Preliminary injunction doctrine recognizes that the task of protecting legal entitlements cannot be postponed until the conclusion of the litigation concerning the assignment of those entitlements. This fact is at odds with the usual law and economics understanding that the assignment and protection of entitlements can be separated and handled sequentially so long as damages atthe conclusion of the case are adequate.10 Accordingly, proponents of the current preliminary injunction doctrine cite the oft-mentioned claim that adequate damages at the conclusion of the case make the entitlement holder whole while encouraging efficient allocation of resources. The most prominent expression of this claim is the so-called “efficient breach hypothesis.”11 This10.Building on Guido Calabresi and A. Douglas Melamed’s framework for analyzinghow legal entitlements are assigned and protected, scholars often look at entitlement protectionin isolation from the assignment of rights. Guido Calabresi & A. Douglas Melamed, Property Rules, Liability Rules, and Inalienability: One View of the Cathedral, 85 H ARV.L.R EV. 1089 (1972). Theories of efficient liability rules begin with certainty over some initial entitlement: Thecourt has already determined to whom the entitlement belongs (or the parties know how thecourt will rule). The parties also know the remedies. Armed with this information, efficient tradeoffs can be made. Unfortunately, parties frequently do not know to whom the court willgrant an entitlement. Preliminary injunctive actions make this indeterminacy quite apparent; yet,the indeterminacy is present in numerous other contexts.11.The efficient breach hypothesis has its origins in seventeenth-century British common law. See Bromage v. Genning,(1616) 81 Eng. Rep. 540 (K.B.). Oliver Wendell Holmes cites Lord Coke in Bromage for support of the fundamental premise of the efficient breach hypothesis: “The duty to keep a contract at common law means . . . you must pay damages if you do not keep it,—and nothing else.” Oliver Wendell Holmes, The Path of theLaw, 10 H ARV.L.R EV. 457, 462 (1897). Departing from this premise, the Holmesian “bad man”—knowing the costs and the benefits of contract completion—is in a good position to determine the efficient remedy. It appears that the term “efficient breach” may have been coined, at least in print, by Charles J. Goetz and Robert E. Scott. See Charles J. Goetz & Robert E. Scott, Liquidated Damages, Penalties and the Just Compensation Principle: SomeNotes on an Enforcement Model and a Theory of Efficient Breach, 77 C OLUM.L.R EV. 554 (1977). Earlier formal treatments of the efficient breach hypothesis were offered by Robert Birmingham, John Barton, and Richard Posner. See R ICHARD A.P OSNER,E CONOMICA NALYSIS OF L AW § 3.8 (1972); John H. Barton, The Economic Basis of Damages for Breach of Contract, 1 J.L EGAL S TUD. 277 (1972); Robert L. Birmingham, Breach of Contract, Damage Measures, and Economic Efficiency, 24 R UTGERS L.R EV. 273 (1970); Robert L. Birmingham, Damage Measures and Economic Rationality: The Geometry of Contract Law, 1969 D UKE L.J. 49. Calabresi and Melamed generalized the insight beyond contracts using liability rules, and this work was expanded and further formalized by Louis Kaplow and Steven Shavell. See Calabresi & Melamed, supra note 10; Louis Kaplow & Steven Shavell, Property Rules Versus Liability Rules: An Economic Analysis, 109 H ARV.L.R EV.713, 725 (1996) (arguing that liability rules (with appropriate court-determined damages) allow infringers, who know whether their own valuations exceed the court’s damages, to make an allocationally efficient choice from their more informed perspective).November 2005] THE PRELIMINARY INJUNCTION DOCTRINE 385 hypothesis maintains that court-ordered expectation damages (a liability rule) lead parties to maintain or abandon prior agreements efficiently. Although this argument was initially focused on contracts, similar efficiency-based arguments have also been made to promote the use of liability rules within the context of tort, property, corporate, and constitutional law.12The basic idea is that if a party is required to compensate anyone harmed by particular conduct, the party, in deciding whether, and with what frequency, to engage in the conduct, will internalize the costs imposed on others and engage in the conduct only to the point at which the benefits of doing so exceed the aggregate costs. Liability rules encourage parties to weigh the costs of avoiding liability—through performance (e.g., completing a contract) or nonperformance (e.g., not causing a nuisance or otherwise interfering with another’s entitlement)—against the costs of facing liability (e.g., breaching the contract and paying the damage remedy or causing a nuisance and paying compensation). Thus, when properly employed, the liability rule remedy, we are constantly reminded, maximizes social welfare. The starting point of our analysis is that such efficiency claims often are wrong.When the assignment of entitlements (and, hence, liability for interference with entitlements) is uncertain, parties rationally discount harms when selecting their course of conduct. Uncertainty biases the estimates that are required under the efficient breach and other efficient “takings” hypotheses. This kind of uncertainty is virtually always present in preliminary proceedings. Yet leading commentators see “no occasion to grant immediate protection” when a “final judgment can remedy the plaintiff’s injuries.”13 We show, however, that the availability of an adequate final remedy is not a sufficient justification for denying preliminary injunctions: adequate compensation at the conclusion of the case does not provide parties with sufficient incentive to engage in efficient conduct before and during the case.14 This point has been obscured by the static Thus, liability rules are able to harness the private information held by the relatively more informed infringers. But cf.Ian Ayres & Paul M. Goldbart, A Critique of “Tangibility” as the Basis of Probability Rules(Yale Law School, Program for Studies in Law, Economics, and Public Policy, Working Paper No. 251, 2002).12.See Ashutosh Bhagwat, Hard Cases and the (D)Evolution of Constitutional Doctrine, 30 C ONN.L.R EV. 961, 1008 (1998) (arguing that liability rules can protect constitutional rights more effectively than property rules in some cases); Calabresi & Melamed, supra note 10; Kaplow & Shavell, supra note 11; Eugene Konotorovich, Liability Rules for Constitutional Rights: The Case of Mass Detentions, 56 S TAN.L.R EV. 755 (2004). But cf. A KHIL R EED A MAR,T HE C ONSTITUTION AND C RIMINAL P ROCEDURE:F IRST P RINCIPLES 115(1997);Jules L. Coleman & Jody Kraus, Rethinking the Theory of Legal Rights, 95 Y ALE L.J. 1335, 1339-40 (1996).13.John Leubsdorf, The Standard for Preliminary Injunctions, 91 H ARV.L.R EV. 525, 541 (1978). Even efficiency-minded judges have echoed this view. See Am. Hosp. Supply Corp. v. Hosp. Prods., 780 F.2d 589, 594 (7th Cir. 1986).mentators have emphasized the incommensurability of damages for certain temporary losses of entitlements: “The right to speak or vote or worship after trial does not replace the right to speak or vote or worship pending trial, and damages for temporary loss58:381386 STANFORD LAW REVIEW [Vol. treatment of preliminary injunctions in the existing academic literature.15 However, it is clear that the preliminary injunctive proceeding is a dynamic process—a process that compels consideration of ex ante motivations and strategic behaviors.16 Viewed from this light, preliminary injunction doctrinecan clearly be seen as an adaptive response to the impairment of parties’ incentives resulting from the uncertainty of entitlement assignments.For concreteness, consider the following hypothetical involving a contractfor the provision of a well-specified good by a seller to a buyer who has paid afixed amount up front.17 If we set the seller’s cost to 70 and the buyer’s valueto 100, performance of the contract would increase social welfare by placingthe good in the hands of the higher-valuing party (the buyer, in this case). The possibility of expectation damages makes it in the personal interest of the sellerto do what is socially desirable. If she does not perform, the seller saves 70 in terms of performance costs but must pay 100 in the form of expectation damages to the buyer. The remedy thus aligns the seller’s incentives with that which is socially desirable. However, this simple implication does not hold when liability is uncertain—a state of the world which, we again emphasize, is reasonably presumed in the context of preliminary injunction hearings.Uncertainty over entitlements changes the efficient breach calculation. For example, imagine that the seller believes there is a 50% chance that her obligation to perform, under the prevailing circumstances, will be legally excused. Under these circumstances, she will not perform (though performance results in the most efficient result), even when expectation damages are perfectly estimated and fully compensatory. When deciding whether to perform, the seller still compares the expected cost of performance (70) to the expected damages for breaching. In this case, however, her expected damagesare now 50, reflecting the expectation damages (100) discounted by the likelihood that the seller will not be held liable for breach (50%).18 So the rational, risk-neutral seller will not perform even though she may be required to make the buyer whole ex post. This is not an efficient result. Liability rules generally (and expectation damages specifically) do not preserve parties’of such rights are not even approximate compensation.” D OUGLAS L AYCOCK,T HE D EATH OFTHE I RREPARABLE I NJURY R ULE 122 (1991). While this point has merit, it is not the one we advance here. Our claim is that even when damages provide approximate and adequate compensation for individual harm, avoidable efficiency losses still accrue.15.Cf. Lanjouw & Lerner, supra note 9.16.Strategic use of preliminary injunctions by plaintiffs is not uncommon. Partiesoften pursue preliminary actions, knowing that they are likely to get the same judge at thefinal stage (especially in state courts) and that judge is unlikely to switch her views of themerits subsequently. This may improve a party’s bargaining power in settlement negotiationsor may offer some other strategic advantage over competitors. See id.17.The upfront payment simplifies our example by allowing us to focus exclusively onthe seller’s breach decision.18.The expected cost of breaching is now a 50% chance of owing 100 and a 50% chance of owing 0 (i.e., (100 × 50%) + (0 × 50%) = 50).November 2005] THE PRELIMINARY INJUNCTION DOCTRINE 387 incentives to behave efficiently in the context of legal uncertainty19—the quintessential context of preliminary hearings.20The preliminary injunction restores efficiency to liability rules by taking the breach decision out of the hands of the compromised seller. At the point where the seller announces that she is going to breach, the buyer (if she does nothing) expects a 50% chance of receiving 100 and nothing otherwise, leaving her with an expected value of 50. If, however, the buyer seeks a preliminary injunction, she will receive a value of 100 through performance, which represents a net expected increase in value of 50 (i.e., 50% × 100) at an expected cost of only 35 (i.e., 50% × 70, representing the 50% chance that she will have to reimburse the seller’s compliance cost if her injunction was granted improperly). As a general matter, it is easy to show that the buyer will compel performance through a preliminary injunction if, and only if, performance is efficient.21 Thus in the presence of legal uncertainty, a key (but largely unappreciated) function of preliminary injunctions is to promote efficiency.Of course, indeterminacy of entitlement is not limited to cases involving preliminary injunctions; it is not uncommon for parties to be unsure of their future liabilities at the stage at which the efficient breach (or taking) hypothesis requires them to calculate the expected costs and benefits of their planned conduct. In these situations, in which the rights to be determined by the proceedings are uncertain, the promised efficiency of liability rules cannot be assured. Therefore, the implications of our analysis reach beyond preliminary injunctions. As a point of departure into our analysis, we now briefly consider the various legal rules which are, or might be, used in deciding whether to granta preliminary injunction.19.Often, with liability rules, defendant-infringer is well positioned to weigh the costs and benefits of her conduct. But uncertainty over entitlements biases her view of the benefits because she is liable for compensating unrealized benefits in only some cases when she infringes, while she faces the costs in all cases when she does not infringe. Preliminary injunctions respond to infringers’ discounting of damages by providing compensation to defendants who are compelled to engage in conduct that is later determined not to be legally required.20.It is also important to emphasize that our results do not rest on an assumption of symmetric perfect information among the parties. In fact, the most significant implication of our model comes from an asymmetric information framework. That is, awarding a preliminary injunction in essence converts a property rule into a temporary liability rule: the party seeking the injunction has a limited call option, wherein she will have to pay court-determined damages if it turns out that the entitlement belongs to the other party. Knowing her private value and the distribution of harms to the other party from complying with the injunction, the liability-rule-like preliminary injunction harnesses the party’s private information. See, e.g., Kaplow & Shavell, supra note 11.21.More generally, if the probability that the court will ultimately award the entitlement to defendant is equal to (1 – P), lπ is plaintiff’s value, and l∆ is defendant’s value, then plaintiff will only seek a preliminary injunction if (1 – P) × lπ > (1 – P) × l∆. See discussion in Part III for a more formal and complete statement of this inequality.388 STANFORD LAW REVIEW [Vol.58:381I.A RTICULATED S TANDARDS FOR P RELIMINARY I NJUNCTIONSAs parties compete to prohibit or permit legally uncertain activities, courtsare asked to allocate consequential legal entitlements in preliminary proceedings without the benefit of a full hearing. In his now-classic study, The Standard for Preliminary Injunctions, John Leubsdorf describes numerous, often inconsistent, articulated bases for preliminary relief: “Irreparable injurymay or may not be mentioned. Sometimes the injunction must not disserve the public interest, sometimes it must serve the public interest, and sometimes onlythe equities of the parties count.”22 Sometimes the decision turns on maintaining the status quo, and other times facilitating change is key.23 Articulated constraints on the merits of plaintiffs’ claims indicate a similar lackof consistency: “One line of cases requires plaintiffs to show a fair question onthe merits, another a substantial probability of success, another a reasonable certainty, and another a clear right.”24Professor Leubsdorf suggests a coherent rationale that underlies this apparent confusion in the judicial opinions. The objective, according to this rationale, is to prevent irreparable injury to the parties’ legal rights.25 Historically, courts of chancery issued injunctions to prevent actions at law aswell as to preserve them. Leubsdorf argues that this latter concern (i.e., preserving and protecting rights at law) was the precursor to contemporary preliminary injunction analysis.26 From this historical line, it is not difficult tosee how one could arrive at a standard based on the prevention of irreparable injury to legal rights.Yet, equitable courts sometimes issued preliminary injunctions that werenot contingent on actions at law or actions in other courts. “In some instances, plaintiffs in suits properly instituted in Chancery needed immediate relief pending the Chancellor’s decision on the merits. They might seek, for example,to stop equitable waste or to secure interim enforcement of a contract.”27 Departing from this historical line of cases might lead one to emphasize a different standard for preliminary relief—a standard, for example, based on the avoidance of waste or efficient enforcement of contracts.2822.Leubsdorf, supra note 13, at 526 (footnotes omitted).23.See Thomas R. Lee, Preliminary Injunctions and the Status Quo, 58 W ASH.&L EEL.R EV. 109, 111 n.4 (2001).24.Leubsdorf, supra note 13, at 526 (footnotes omitted).25.Clearly visible traces of this objective were observable in eighteenth-century English common law courts, where the separation of legal and equitable proceedings frequently prompted judges to issue preliminary relief to protect rights at equity and law. Id.at 527-32.26.Id. at 528 (“Only [this class of cases] raised problems calling for the kind of analysis we now apply, and the particularities of that class have shaped later learning on the standard for preliminary injunctions.”).27.Id. at 529.28.Indeed, as Professor Leubsdorf notes, “[o]wing in part to Jeremy Bentham . . . . theNovember 2005] THE PRELIMINARY INJUNCTION DOCTRINE 389 In his essay, Leubsdorf himself was quite hostile to the notion of judges making utilitarian calculations when considering the issuance of preliminary injunctions:29 “The court’s function is to protect rights, not to increase the gross national product.”30 However, when rights are uncertain, as they are in preliminary hearings, why shouldn’t courts consider whether granting the injunction will increase social welfare or avoid waste? This, admittedly, is not among the stated justifications for preliminary injunctions advanced in judicial opinions. These opinions, for the most part, take an ex post view, in which the articulated concern is that damages awarded at the conclusion of the case may be inadequate to compensate plaintiff for harm suffered during the pendency of the case.31A. Traditional ApproachesDespite the rhetorical variation in the case law, there is a widely shared view that the purposes served by preliminary injunctions are maintaining the status quo between the parties, preserving the court’s ability to consider the case fully, and minimizing the harm caused by erroneous preliminary decisions. There is less apparent consensus on the best way to achieve these ends through the use of preliminary injunctions. Most courts, when deciding whether to grant an injunction, rely on a four-part standard that (to varying degrees) considers (1) plaintiff’s likelihood of success on the merits, (2) the amount of irreparable utilitarian tide [that swept] away the division between law and equity [also] shaped thought on preliminary injunctions, setting that thought adrift in search of a new foundation.” Id. at 532 (footnotes omitted). Could this tide not have carried judicial thought about preliminary injunctions to utilitarian shores? After all, it was around this time that “courts came to require plaintiffs seeking interlocutory relief to accept liability for resulting damage” to defendants. Id. at 534. And this requirement is, as we argue below, an essential move to assure efficiency through the use of preliminary injunctions.29.Leubsdorf maintained this attitude: “Even in common law nuisance cases where the court must perform something like a cost-benefit analysis at trial, other considerations control at the interlocutory hearing.” Id. at 543 n.101.Leubsdorf felt that at the interlocutory hearing, the court’s “goal is to assess the probable loss of rights under various courses of action, not to appraise the net social benefit from those courses.” Id. (emphasis added).30.Id. at 555. Efficiency could never be a sufficient warrant for “interim accommodation,” according to Leubsdorf. Irreparability is always a necessary condition: “The plaintiff must always demonstrate the possibility of irreparable loss.” Id. at 551. Leubsdorf did, however, recognize one category of preliminary injunctions—so-called “statutory injunctions”—in which social policy may justify preliminary intervention without a showing of irreparability. In these instances, “[t]he goal is not to minimize loss of rights in specific cases, but to isolate classes of cases in which granting or denying relief under specified tests will minimize harm to public policies.” Id. at 565. But, of course, public policy might reasonably include increasing aggregate social welfare or the gross national product.31.See, e.g., Am. Hosp. Supply Corp. v. Hosp. Prods., 780 F.2d 589, 594 (7th Cir. 1986) (“The premise of the preliminary injunction is that the remedy available at the end of trial will not make the plaintiff whole; and, in a sense, the more limited that remedy, the stronger the argument for a preliminary injunction . . . .”).。

司威特Civetta：超声波驱鼠器原理

目前，成熟的驱鼠技术有红外线驱鼠、电磁波驱鼠和超声波驱鼠等，但是都存在着一些弊端，致使驱鼠效果不如人意。

本驱鼠器采用基于仿生学原理，运用现代集成电路技术，通过在现有超声波电路上加装可以发出高保真语音猫叫声的电路，使得超声波和高保真语音猫叫声叠加和互补，覆盖整个防治区，以克服超声波存在盲区的缺点，从而达到强劲的驱鼠效果。

同时改进超声波发射电路，使其连续发出高频无规律变化的震荡波，以克服现有超声波驱鼠器发射频带窄、频率相对稳定且有一定周期性的缺点。

避免鼠类对某一频段的“适应性”。

1 总体设计本系统的设计总体分为4个模块，即：电源模块，超声波模块，音频模块，控制器模块。

电源模块为整个系统提供5V的直流电并且实现整流滤波稳压电源与收稿日期：2009—03—12作者简介：张建龙，主要研究方向：机械与电子技术。

电池组的自由切换。

超声波模块主要发出频率可变的让老鼠神经系统不适的超声波。

音频模块产生老鼠死亡时的绝叫声产生驱鼠效果。

控制器模块运用单片机进行控制，实现超声波模块和音频模块之间的切换，进行分时控制系统工作原理：首先，电源模块给系统供电。

其中，电源模块有两种工作模式，一种是接市电然后整流滤波稳压供电，另一种是电池供电，两种模式可通过转换开关自由切换。

控制器(基于单片机和光电传感器实现)控制超声波模块和音频模块工作，实现两个模块的循环工作和模块间的自由切换。

具体的系统总体布局如图1所示。

图l给出了各个模块的物理连接关系，即电器特性。

图1 系统原理框图湖南农机 2009年5月2 模块设计2．1 超声波模块(1)原理：超声波模块电路如图2所示，超声波模块上电后，经过采样放大电路产生矩形脉冲信号，然后将信号送给信号选择电路，将经过信号选择电路后的信号送给多谐振荡电路，振荡电路将其信号协调，稳定后把信号送给推挽放大电路．信号放大电路将信号功率放大后给超声波扬声器，从而发出超声波信号。

图a 图b图。

图d图e图2 超声波模块电路(2)仿真及结果：在multisim8中调出超声波模块的信号采样放大电路、信号选择电路、多谐振荡电路、推挽放大电路所需器件和超声波扬声器。

Pin1At Encoding a Peptidyl-Prolyl cis,trans isomerase regulates flowering time in arabidopsis

Molecular CellArticlePin1At Encoding a Peptidyl-Prolyl cis/trans Isomerase Regulates Flowering Time in ArabidopsisYu Wang,1,2Chang Liu,1,2Daiwen Yang,1Hao Yu,1,2,*and Yih-Cherng Liou1,*1Department of Biological Sciences,Faculty of Science2Temasek Life Sciences Laboratory,1Research LinkNational University of Singapore,Singapore*Correspondence:dbsyuhao@.sg(H.Y.),dbslyc@.sg(Y.-C.L.)DOI10.1016/j.molcel.2009.12.020SUMMARYFloral transition in plants is regulated by an inte-grated network ofﬂowering genetic pathways.We show that an Arabidopsis PIN1-type parvulin1, Pin1At,controlsﬂoral transition by accelerating cis/trans isomerization of the phosphorylated Ser/ Thr-Pro motifs in two MADS-domain transcription factors,SUPPRESSOR OF OVEREXPRESSION OF CO1(SOC1)and AGAMOUS-LIKE24(AGL24). Pin1At regulatesﬂowering,which is genetically mediated by AGL24and SOC1.Pin1At interacts with the phosphorylated AGL24and SOC1in vitro and with AGL24and SOC1in vivo and accelerates the cis/trans conformational change of phosphory-lated Ser/Thr-Pro motifs of AGL24and SOC1.We further demonstrate that these Ser/Thr-Pro motifs are important for Pin1At function in promotingﬂow-ering through AGL24and SOC1and that the interac-tion between Pin1At and AGL24mediates the AGL24 stability in the nucleus.Taken together,we propose that phosphorylation-dependent prolyl cis/trans isomerization of key transcription factors is an impor-tantﬂowering regulatory mechanism. INTRODUCTIONFloral transition in Arabidopsis is coordinately controlled by multiple genetic pathways in response to various developmental and environmental cues(Koornneef et al.,1998;Levy and Dean, 1998;Mouradov et al.,2002).The autonomous and gibberellic acid(GA)pathways are responsive to endogenous develop-mental and physiological state,while the photoperiod and vernalization pathways monitor the alteration of environmental signals such as day length and temperature.These genetic path-ways ultimately converge at theﬂoral pathway integrators,which in turn regulate the activity ofﬂower meristem identity genes to initiate the transition from vegetative to reproductive growth. Regulatory genes acting at the convergence point of the multiple ﬂoral induction pathways include two MADS-box transcription factors,SOC1and AGL24(Lee et al.,2000;Liu et al.,2008; Michaels et al.,2003;Samach et al.,2000;Yu et al.,2002).Peptidyl-prolyl cis/trans isomerases(PPIases)are enzymes that accelerate energetically unfavorable cis/trans isomerization of the peptide bond preceding a proline(Hunter,1998;Kiefhaber et al.,1990).PPIases include four structurally distinct subfam-ilies:cyclophilins,FK506-binding proteins,parvulins,and PP2A phosphatase activator(Lu et al.,2007).Members from the parvu-lin subfamily,such as PIN1from human and ESS/PTF1from Saccharomyces cerevisiae,have been shown to be essential for cell cycle and growth(Hanes et al.,1989;Hani et al.,1995; Lu et al.,1996).In the parvulin subfamily,PIN1-like PPIases are the only type of PPIases that speciﬁcally recognize phosphory-lated Ser/Thr residues preceding proline(pSer/Thr-Pro)and catalyze the conformational change of the phosphorylated substrates,thereby controlling their function(Hsu et al.,2001; Huang et al.,2001;Liou et al.,2002,2003;Lu et al.,1996, 1999;Pastorino et al.,2006;Ranganathan et al.,1997;Stuken-berg and Kirschner,2001;Yaffe et al.,1997).Pin1At was early-identiﬁed as the only PIN1-type PPIase from Arabidopsis(He et al.,2004;Landrieu et al.,2000).Sequence comparison showed that PIN1homologs from human,yeast, and Drosophila consist of two domains,an N-terminal WW regu-latory domain and a C-terminal PPIase catalytic domain, whereas plant PIN1s,including Pin1At,contain only a PPIase domain with four additional amino acids(Figure S1)(Yao et al., 2001).Although several Pin1homologs have been identiﬁed in plants(Landrieu et al.,2000;Metzner et al.,2001;Yao et al., 2001),their substrates and biological function in plants are so far unknown.Here,we show that Pin1At affectsﬂoral transition in Arabidopsis and that phosphorylation-dependent prolyl cis/ trans isomerization of key transcription factors such as SOC1 and AGL24by Pin1At emerges as an importantﬂowering regula-tory mechanism.RESULTSPin1At Promotes FloweringTo investigate the biological function of Pin1At,weﬁrst exam-ined the effect of modulating Pin1At expression in Arabidopsis. Since insertion mutants were not available in public resources, transgenic plants with antisense suppression of Pin1At were generated.Among56transgenic lines containing Pin1At N-terminal antisense fragment driven by a double cauliﬂower mosaic virus35S promoter(Pin1At-AS),30plants showed late ﬂowering under long days(LDs)(Figures1A and1B).Underboth long and short days (SDs),representative Pin1At-AS plants with reduced expression of Pin1At ﬂowered much later than wild-type plants (Figures 1E,1F,and S2A).On the contrary,among 39transgenic plants containing Pin1At cDNA under the control of 35S promoter (35S:Pin1At ),21showed early ﬂowering under LDs (Figures 1C and 1D).Representative 35S:Pin1At lines with overexpression of Pin1At showed early ﬂowering under both LDs and SDs (Figures 1E,1F,and S2B).In addition,these plants also exhibited serrated rosette and cauline leaves (Figure 1D).These observations suggest that Pin1At at least affects ﬂowering and leaf development.The Photoperiod and Vernalization Pathways Affect Pin1At ExpressionTo examine the ﬂowering pathways that regulate Pin1At ,we examined its expression in various environmental conditions and ﬂowering mutants.In wild-type Col plants under LDs,Pin1At expression gradually increased during ﬂoral transition occurring from 9to 13days after germination (Figure 2A)and decreased afterwards.On the contrary,its expression was not signiﬁcantly changed under SDs within 21days after germination.These results suggest that the photoperiod pathway affectsPin1AtFigure 1.Pin1At Regulates Flowering Time in Arabidopsis(A and B)Wild-type plants (A)show earlier ﬂower-ing than representative Pin1At antisense plants (line 18-3)(B)at 35days after germination under long days.(C and D)Wild-type plants (C)show later ﬂowering than representative 35S:Pin1At plants (line 22-5)(D)at 28days after germination under long days.(E and F)Flowering time of Pin1At transgenic plants under long days (E)and short days (F).The number of rosette leaves on the main shoot represents ﬂowering time.Values presenting the mean ±standard deviation were scored from at least 15plants of each genotype.Signiﬁcant differences in comparison with wild-type plants are indicated with asterisks:*p <0.05;**p <0.01,by Student’s t test.(G)Effect of antisense suppression of Pin1At (line 18-3)on overexpression of various ﬂowering promoters under long days.Error bars indicate standard deviation.Signiﬁcant differences between with and without antisense suppression of Pin1At are indicated with asterisks:*p <0.05,by Student’s t test.(H)Effect of overexpression of Pin1At (line 22-5)on various ﬂowering mutants under long days.Error bars indicate standard deviation.Signiﬁcant differences between with and without overexpres-sion of Pin1At are indicated with asterisks:*p <0.05,by Student’s t test.expression.Further examination of Pi-n1At expression revealed that its expres-sion was affected by CONSTANS (CO ),but not FLOWERING LOCUS T (FT )(Figure S3).Pin1At expression was also affected by vernalization (Figure 2B),butnot by autonomous pathway mutants and GA treatment (Figures S4and S5).Notably,dramatic downregulation of a ﬂowering repressor,FLOWERING LOCUS C (FLC ),in FRI FLC ,wherein the dominant allele of FRIGIDA (FRI )causes high expression of FLC by vernalization,did not enhance the upregulation of Pin1At (Figure 2B),indicating that vernalization regulates Pin1At in an FLC -independent manner.Regulation of Pin1At by the vernal-ization pathway partly explains that manipulation of Pin1At expression affects ﬂowering time in SDs,under which the LD photoperiod pathway is not activated.Pin1At Regulates Flowering Time through AGL24and SOC1Since the photoperiod and vernalization pathways converge on the regulation of Pin1At expression,we speculated that Pin1At function may be relevant to ﬂowering regulators located downstream of several genetic pathways,such as SOC1,FT ,and AGL24(Kardailsky et al.,1999;Kobayashi et al.,1999;Lee et al.,2000;Michaels et al.,2003;Samach et al.,2000;Yu et al.,2002).Thus,we performed genetic crossing to iden-tify potential interacting regulators of Pin1At .While downregu-lation of Pin1At in Pin1At-AS caused late ﬂowering,it did notMolecular CellProtein Isomerization Mediates Floweringaffect early ﬂowering conferred by constitutive expression of CO and FT (Figure 1G).On the contrary,early ﬂowering of 35S:SOC1and 35S:AGL24was delayed in Pin1At-AS back-ground (Figure 1G).These observations imply that promotion of ﬂowering by SOC1and AGL24is partially dependent on Pin1At .We further crossed 35S:Pin1At with several late-ﬂowering loss-of-function mutants (Figure 1H).35S:Pin1At promoted ﬂow-ering in co-1mutants,indicating that Pin1At could act down-stream of or in parallel with CO .Comparatively,35S:Pin1AtFigure 2.Pin1At Expression Pattern and Protein Localization(A)Temporal expression of Pin1At in wild-type plants grown under long days (LD)and short days (SD).Error bars indicate standard deviation.(B)Effect of vernalization on Pin1At expression.For vernalization treat-ment,seeds were sown on Murashige and Skoog (MS)agar plates and incubated at 4 C under low light levels for 8weeks.The relative expression of FLC ,SOC1,and Pin1At in 9-day-old seedlings grown in LDs was compared.Quantitative real-time PCR data (A and B)were normalized against the TUB2expression.Error bars indicate standard deviation.(C–F)In situ localization of Pin1At expression.Sections of shoot apices of 11-day-old (C)and 35-day-old (E)plants were hybridized with Pin1At anti-sense probe,while the corresponding control sections (D and F)were hybridized with the sense probe.Scale bars,25m m.(G–J)Subcellular localization of Pin1At-GFP fusion protein in Arabidopsis protoplasts.GFP localization is observed in protoplasts transfected with 35S:Pin1At-GFP (G)and a control 35S:GFP construct (I).Their respective chlorophyll red autoﬂuorescence is also shown (H and J).only slightly promoted ﬂowering in soc1-2and agl24-1mutants.In particular,early ﬂowering of 35S:Pin1At was completely suppressed by soc1-2agl24-1(Figure 1H),sug-gesting that 35S:Pin1At function is mediated by AGL24and SOC1.We further found that the mRNA expression of AGL24and SOC1was not affected by suppression or over-expression of Pin1At (Figure S6A).Pin1At mRNA expression was also not signiﬁcantly affected by AGL24and SOC1(Figure S6B).These observations demonstrate that Pin1At and ﬂowering time regulators SOC1and AGL24are mutually dependent for their function in ﬂowering,which is,however,not mediated by mutual transcriptional regulation.Pin1At mRNA was expressed in all the tissues examined,with the highest expression in cauline and rosette leaves (Figure S7).Pin1At transcripts were localized in the shoot apical meristem during the ﬂoral transition (Figures 2C and 2D)and later in the inﬂorescence shoot apical meristem and emerging ﬂoral meristems (Figures 2E and 2F).Expres-sion of AGL24and SOC1was also shown to be upregulated in the shoot apical meristem during the ﬂoral transition (Michaels et al.,2003;Yu et al.,2002;Lee et al.,2000;Sam-ach et al.,2000),which is concomitant with the Pin1At expression,indicating that they could interact to control ﬂow-ering time.We then investigated the subcellular localization of Pin1At by Arabidopsis protoplast transfection assay using a fusion construct of Pin1At-GFP.Like 35S:GFP,Pin1At-GFP localized in both the cytoplasm and nucleus (Figures 2G–2J),implying that Pin1At may exert its function in multiple cell organelles.AGL24and SOC1Are Phosphorylated during Plant DevelopmentTo investigate whether AGL24and SOC1interact with Pin1At,we ﬁrst tested their phosphorylation status,because PIN1-type isomerases bind only to phosphorylated substrates (Hani et al.,1999;Yaffe et al.,1997).Immunoblot analysis of protein extracts from 35S:AGL24-6HA ,where AGL24-6HA retains the sameMolecular CellProtein Isomerization Mediates Floweringbiological function as AGL24in promotingﬂowering(Liu et al., 2008),revealed two speciﬁc bands recognized by HA antibody (Figure3A).The lower faint band with a molecular mass of approximately31kDa was consistent with the predicted size of the fusion protein AGL24-6HA.As phosphorylated proteins often have slower mobility on an SDS-PAGE gel,the dominant upper band was probably the phosphorylated form of AGL24-6HA.To test this,35S:AGL24-6HA protein extracts were treated with calf intestinal alkaline phosphatase(CIAP)for different time points.Immunoblot analysis showed that the amount of the major(upper)band was gradually reduced(Figure3C),resulting in the increased intensity of the lower band.This suggests that the slow-and fast-migrating bands represent the phosphory-lated and nonphosphorylated forms of AGL24-6HA,respec-tively.Similarly,immunoblot analysis of protein extracts from 35S:SOC1-9Myc,where SOC1-9Myc promotesﬂowering as SOC1(Liu et al.,2008),also showed two bands with different mobility(Figure3B).After CIAP treatment,the intensity of the slow-and fast-migrating bands was reduced and increased (Figure3D),respectively,indicating that SOC1-9Myc proteins also exist as the phosphorylated and nonphosphorylated forms. We further performed immunoblot analysis to examine the temporal phosphorylation status of AGL24and SOC1in devel-oping plants(Figure3E).The phosphorylated form of AGL24-6HA was prominently expressed in35S:AGL24-6HA over the developmental stages from young vegetative plants(day4)to bolting plants(day28).The phosphorylated form of SOC1-9Myc was highly expressed in35S:SOC1-9Myc at all stages examined,while the amount of its unphosphorylated form grad-ually increased.Thus,phosphorylation of AGL24and SOC1 proteins occurs in developing plants,indicating that their func-tion is likely regulated by the phosphorylation/dephosphorylation mechanism.Pin1At Interacts with Phosphorylated SOC1and AGL24 To examine if Pin1At directly interacts with SOC1and AGL24,we performed GST pull-down assays.The phosphorylated AGL24-6HA and SOC1-9Myc from35S:AGL24-6HA and35S:SOC1-9Myc plants,respectively,were pulled down by GST-Pin1At, but not by GST control beads(Figures3F and3G).Because the amount of AGL24-6HA and SOC1-9Myc unphosphorylated forms was low in the plant extracts,CIAP-treated proteins were further tested if Pin1At also interacts with the unphosphory-lated proteins(Figures3H and3I).Although the unphosphory-lated proteins increased signiﬁcantly after CIAP treatment,they were not pulled down by GST-Pin1At.These results indicate that Pin1At speciﬁcally interacts with the phosphorylated SOC1and AGL24in vitro.Furthermore,bimolecularﬂuores-cence complementation(BiFC)analysis(Ohad et al.,2007), which examines protein-protein interactions through monitoring theﬂuorescence emitted by reconstitution of an enhanced yellowﬂuorescent protein from two fragments(N-and C-terminal halves)fused to two interacting proteins,revealed the direct interaction of Pin1At-AGL24(Figure3J)and Pin1At-SOC1(Figure3K)in the nuclei of living plant cells.Coimmunopre-cipitation analysis on the protein extracts from35S:AGL24-6HA 35S:Pin1At further conﬁrmed the in vivo interaction of AGL24 and Pin1At(Figure3L).As PIN1-type isomerases speciﬁcally recognize phosphory-lated Ser/Thr-Pro motifs,we examined whether phosphorylation of AGL24and SOC1occurs at Ser/Thr-Pro motifs using the mitotic phosphoprotein monoclonal-2(MPM-2)antibody that speciﬁcally recognizes phosphorylated Ser/Thr-Pro motifs in many phosphoproteins(Davis et al.,1983).MPM-2antibody detected the phosphorylated forms of AGL24-6HA and SOC1-9Myc,but not the unphosphorylated forms resulting from CIAP treatment(Figures3M and3N),suggesting that the Thr-Pro motif in AGL24and Ser-Pro motifs in SOC1are phosphorylated.Pin1At Catalyzes the Conformational Changeof Ser/Thr-Pro Motifs in AGL24and SOC1We further used nuclear magnetic resonance(NMR)spectros-copy to examine if Pin1At catalyzes the cis/trans conformational exchange of the phosphorylated Ser/Thr-Pro motifs in SOC1and AGL24at per residue resolution.To this end,we synthesized the phosphorylated/nonphosphorylated peptides—SLIIF(p)SPKG-KLYE,which were derived from one of the two Ser-Pro motifs in SOC1,and SSYDSG(p)TPLEDDSD,which were derived from the only Thr-Pro motif in AGL24—and determined their confor-mational exchanges in response to Pin1At.Because of slow exchange between proline cis and trans conformations,many residues in both phosphorylated and nonphosphorylated peptides displayed two distinct sets of1H signals in the ROESY (rotating frame Overhauser effect spectroscopy)and TOCSY (total correlation spectroscopy)spectra(Figures4A,4B,S8, and S9).Only partial assignment of the peptide signals was obtained on the basis of the TOCSY and ROESY experiments due to severe signal overlap.The cis and trans populations of the peptides,regardless of their phosphorylation status,were $10%and90%,respectively,as estimated from the intensities of well-resolved peaks in the one-dimensional1H spectra.In the absence of Pin1At,no exchange cross peaks were observed in the ROESY spectra of the phosphorylated AGL24 and SOC1peptides(Figures4A and S8A),indicating that the exchange between the cis and trans conformations is too slow on the NMR timescale(<0.1sÀ1).In contrast,in the presence of Pin1At,we detected the exchange peaks resulting from proline isomerization in AGL24-and SOC1-phosphorylated peptides(Figures4B and S8B).Taking the intensities of cross and diagonal peaks of Leu204and Thr202amide protons from the phosphorylated AGL24peptides,we further calculated the isomerization rates from cis to trans(k ct cat)and from trans to cis(k tc cat)conformations(Figures4C and4D).The values of k ct cat and k tc cat obtained from I tt and I tc intensities for Thr202were8.7 and0.8sÀ1,respectively,while the respective values for Leu204 were9.8and1.3sÀ1(Figures4E and4F).The results measured from two different residues were consistent and revealed that the exchange rate from the cis to trans conformation(k ct cat)was about8–10times larger than that from the trans to cis conforma-tions(k tc cat),which was expected from the trans and cis pop-ulation ratio($9:1).The isomerization rates catalyzed by Pin1At (k ct cat and k tc cat)were signiﬁcantly higher than those without Pi-n1At(k ct and k tc)(Figure4F),demonstrating that isomerization of phosphorylated AGL24peptides was dramatically enhanced by Pin1At(Figure4G).On the contrary,the nonphosphorylated peptides(both AGL24and SOC1)displayed no exchange peaksMolecular CellProtein Isomerization Mediates FloweringMolecular CellProtein Isomerization Mediates FloweringFigure3.Phosphorylation of AGL24and SOC1and Their Interaction with Pin1At(A)AGL24-6HA proteins exist as two forms(arrowhead and arrow)in35S:AGL24-6HA.Total proteins extracted from2-week-old plants were analyzed by immu-noblot with anti-HA antibody.(B)SOC1-9Myc proteins exist as two forms(arrowhead and arrow)in35S:SOC1-9Myc.Total proteins extracted from2-week-old plants were analyzed by immu-noblot with anti-Myc antibody.(C)CIAP treatment of proteins immunoprecipitated from35S:AGL24-6HA.After CIAP treatment,phosphorylated AGL24-6HA protein(arrowhead)was converted into the unphosphorylated form(arrow).(D)CIAP treatment of proteins immunoprecipitated from35S:SOC1-9Myc.After CIAP treatment,phosphorylated SOC1-9Myc protein(arrowhead)was con-verted into the unphosphorylated form(arrow).(E)Temporal status of AGL24and SOC1phosphorylation in4-to28-day-old35S:AGL24-6HA and35S:SOC1-9Myc plants,respectively.(F and G)GST pull-down assay of interaction of Pin1At with phosphorylated AGL24-6HA(F)and SOC1-9Myc(G).GST or GST-Pin1At beads were incubated with the protein extracts from35S:AGL24-6HA or35S:SOC1-9Myc plants.The beads were subjected to immunoblot analysis with anti-HA(F)or anti-Myc(G)antibody in the upper panel.Arrowhead and arrow indicate the phosphorylated and unphosphorylated form,respectively.(H and I)GST pull-down assay of interaction of Pin1At with unphosphorylated AGL24-6HA(H)and SOC1-9Myc(I).The proteins immunoprecipitated from 35S:AGL24-6HA or35S:SOC1-9Myc using anti-HA or anti-Myc,respectively,were pretreated with CIAP and incubated with GST or GST-Pin1At beads.The beads were subsequently analyzed as in(F and G).in both the presence and absence of Pin1At (Figure S9).These ﬁndings,together with the protein interaction results shown by GST pull-down and BiFC assays (Figures 3F to 3K),suggestFigure 4.Pin1At Catalyzes Cis /Trans Isomeriza-tion of pThr-Pro Motifs in AGL24(A and B)Selected region of two-dimensional ROESY spectra of the phosphorylated AGL24peptide in the absence (A)or presence (B)of Pin1At at a mixing time of 110ms.Negative and positive peaks are displayed in red and blue,respectively.Diagonal peaks from cis and trans conformers are indicated by cc and tt,respectively,while exchange peaks resulting from Pin1At-catalyzed isomerization are labeled by ct and tc.Note that ROE and exchange cross peaks are positive and negative,respectively.(C and D)Dependence of ratios of cross/diagonal peak intensities for cis and trans Leu204-HN (C)and Thr202-HN (D)on ROE mixing times.Experimental data are ﬁt to a two-site exchange model,and the ﬁtting curves are indi-cated by solid lines.(E)Enzyme kinetic scheme of Pin1At catalytic isomeriza-tion of the phosphorylated Thr202-Pro bond of AGL24.(F)Pin1At-catalyzed isomerization rates from cis to trans (k ct cat )and from trans to cis (k tc cat )generated from inde-pendent ﬁtting of the intensity ratios of ROESY peaks from (C)and (D).(G)Structural model represents the catalytic isomerization of Pin1At on phosphorylated Thr202-Pro bond of AGL24.In the absence of Pin1At (in blue),the conformational changes between cis (trans )and trans (cis )are very slow,while in the presence of Pin1At (in red),the conformational changes of prolyl-peptidyl bond of AGL24are dramatically accelerated.that Pin1At binds to the phosphorylated Ser/Thr-Pro motifs in AGL24and SOC1and cata-lyzes their cis/trans isomerization.Compared to their homologs in other species,plant PIN1homologs contain an extra four amino acid insertion in their PPIase domains (Figure S1).Deletion of these four amino acids has been shown to abolish the ability of Pin1At to rescue the lethal phenotype of yeast Ess1mutation under nonoverexpression conditions,indicating its critical role in mediating the substrate interaction of Pin1At (Yao et al.,2001).We thus constructed the Pin1At mutant protein (mPin1At)with deletion of these four amino acids to test their function in mediating Pin1At enzyme activity.While GST-mPin1At was still able to bind to the Myc-tagged AGL24and SOC1(Figure S10),NMR analysisrevealed that there was no isomerization of AGL24peptide by mPin1At (Figure S11),suggesting that these plant-speciﬁc amino acids are essential for the enzyme activity of Pin1At.(J and K)BiFC analysis of the interaction between Pin1At and AGL24(J)or SOC1(K).DAPI,ﬂuorescence of 40,6-diamino-2-phenylindol;EYFP,ﬂuorescence of enhanced yellow ﬂuorescent protein;Merge,merge of DAPI and EYFP.(L)In vivo interaction between Pin1At and AGL24-6HA.Nuclear extracts from 35S:Pin1At 35S:AGL24-6HA double transgenic plants were immunoprecipitated by either anti-Myc or anti-HA agarose beads.The coimmunoprecipitated proteins were analyzed using anti-Pin1At antibody.(M and N)Phosphorylation of AGL24and SOC1on the Ser/Thr-Pro motifs.The proteins immunoprecipitated from 35S:AGL24-6HA (M)or 35S:SOC1-9Myc (N)were treated with or without CIAP.The resulting products were subjected to immunoblot analysis with anti-HA (M)or anti-Myc (N)antibody in the upper panel and with the MPM-2antibody in the lower panels (M and N).Molecular CellProtein Isomerization Mediates FloweringTo test whether this four amino acid insertion is relevant to Pin1At function in the control of ﬂowering time,we have overexpressed the mutated Pin1At in Arabidopsis and obtained 25transgenic plants.All of these transgenic plants showed similar ﬂowering time as wild-type plants under LDs (data not shown),which is different from the early ﬂowering phenotypes exhibited by over-expression of wild-type Pin1At (Figure 1E),further indicating that Pin1At function in ﬂowering time control depends on its isomer-izationfunction.Figure 5.Mutation of pSer/Thr-Pro Motifs in AGL24and SOC1Affects Flowering Time(A)Schematic diagram of the mutations in AGL24and SOC1proteins.There are four characteristic domains of MADS-box transcription factors,including MADS-box (M),intervening (I),keratin-like (K),and C-terminal (C)domains.Arrows indicate the sites containing pSer/Thr-Pro motifs.The mutated amino acids are indicated by asterisks.(B)Distribution of ﬂowering time in T1transgenic plants carrying the wild-type AGL24gene (gAGL24)and its mutated form (gAGL24-AP )in the agl24-1mutant background.(C)Distribution of ﬂowering time in T1transgenic plants carrying the wild-type SOC1gene (gSOC1)and its mutated form (gSOC1-2AP )in the soc1-2mutant background.(D)Flowering time of 35S:Pin1At is dependent on the pSer/Thr-Pro motifs in AGL24and SOC1.Values presenting the mean ±standard deviation were scored from at least 15plants of each genotype.Signiﬁcant differ-ences in comparison with wild-type plants are indicated with asterisks:*p <0.05,by Student’s t test.Mutagenesis of Ser/Thr-Pro Motifs in SOC1and AGL24Affects Flowering TimeIf Pin1At effect on ﬂowering is mediated through its interac-tion with phosphorylated Ser/Thr-Pro motifs in SOC1and AGL24,mutagenesis of these motifs would affect ﬂowering time.Thus,we substituted Thr 202with Ala in the Thr-Pro motif of AGL24and Ser 49and Ser 195with Ala in the Ser-Pro motifs of SOC1in their respective genomic constructs (Figure 5A).Previous studies have demonstrated that the native AGL24and SOC1genomic fragments used in this study are able to largely rescue late ﬂowering of their respective loss-of-function mutants (Liu et al.,2008;Samach et al.,2000).The average ﬂowering time of agl24-1or soc1-2mutants trans-formed with their respective native genomic fragments was around 14rosette leaves,which was comparable with that of wild-type plants (12rosette leaves)(Figures 5B and 5C).However,agl24-1mutants transformed with the mutated Thr-Pro motif construct,gAGL24-AP ,and soc1-2mutants transformed with the mutated Ser-Pro motif construct,gSOC1-2AP ,ﬂowered much later with around 18and 22rosette leaves,respectively (Figures 5B and 5C),demon-strating that mutation of Ser/Thr-Pro motifs in AGL24and SOC1delays ﬂowering.To study if the mutations in Ser/Thr-Pro motifs affect the ability of AGL24and SOC1as substrates of Pin1At-mediated isomerization,we further tested whether Pin1At could cata-lyze the isomerization of the mutated Thr-Pro motif in AGL24.To this end,we synthesized a peptide,SSYDSGA-PLEDDSD,in which TP was mutated into AP,and examined its conformational change by NMR spectroscopy.No confor-mational exchange was observed in the absence or presence of Pin1At (Figure S12),suggesting that the Thr-Pro motif is essential for AGL24to serve as a Pin1At substrate.To conﬁrm that Pin1At affects ﬂowering through these Ser/Thr-Pro motifs,we further crossed the representative transgenic lines (agl24+gAGL24,agl24+gAGL24-AP ,soc1+gSOC1,and soc1+gSOC1-2AP )that showed an average ﬂowering time of their respective populations with 35S:Pin1At agl24-1and 35S:Pin1At soc1-2.While overexpression of Pin1At promotesMolecular CellProtein Isomerization Mediates Flowering。

on An Uncertain Model

– ii –
Contents
1 Introduction
1
2 Problem Formulation 2 2.1 A Teaching Scientist Inducement Model . . . . . . . . . . . . . . . . . . . . 2 2.2 A Research Scientist Inducement Model . . . . . . . . . . . . . . . . . . . . 7 2.3 A Teaching and Research Scientist Inducement Model . . . . . . . . . . . . 12 3 Conclusion 4 Appendix 22 23
The problem of allocation of resources to carry out scientiﬁc activities for attaining certain economic and social objectives has been the concern not only of economists, but also of policy makers, and sociopolitical scientists. As both teaching and research scientists contribute directly or indirectly to the scientiﬁc progress and hence the economic growth of a society, it is important for policy makers and administrators to allocate public funds in the “best” possible manner. However, in their allocation of resources, including human resources, to scientiﬁc activities, they are confronted with a multitude of choices such as the choice among ﬁelds of scientiﬁc activities and projects to support, as well as the choice among educational and research institutions. Among others, Intriligator [1], Intriligator and Smith [2], Stoikov [3], Bolt, Koltun, and Levine [4] have investigated one aspect of the problem of choice, namely, the allocation of new doctoral scientists between teaching and research careers. This aspect of the problem has attracted much interest because an inadequate allocation of new scientists teaching in higher education may weaken the educational process. Equally serious is the situation when private and public research establishments do not have a suﬃcient number of new scientists to carry out important research projects which directly aﬀect the economic growth of a society. In [1, 2], the authors studied the problem of allocation of new scientists by formulating it as a constrained optimal control problem with the numbers of research scientists and teaching scientists as state variables and the allocation proportion as control variable. The objective function to be maximized is a welfare function which consists of a future welfare component and an intermediate welfare component; the allocation proportion is constrained to lie within two speciﬁed limits. In this paper, we attempt to address the allocation problem of new scientists between teaching and research in a manner diﬀerent from that used in [1, 2]. With uncertainty present in the system parameters and the control constraints, we wish to determine the fractions of new scientists which must be induced to go into teaching and research careers in order to achieve, within a given or at least computable time interval, desired numbers of each or a prescribed number of one or the other. These fractions are obtained as functions of the current numbers of educators and researchers, utilizing the robust control theory developed in [5-8] and summarized in the Appendix.

vietuz

292UuU viÕt t¾t cña uracil.ubiquitin A small protein, present in all eukaryotic cells, which plays an important role in tagging protein s destined for proteolytic cleavage (because they are damaged or no longer needed). ubiquitin Protein ph©n tö nhá, cã mÆt trong tÊt c¶ c¸c tÕ bμo nh©n chuÈn, ®ãng vai trß quan träng trong c¸c protein g¾n nh·n ph©n t¸ch thñy ph©n protein (bëi v×chóng bÞ huû hoÆc kh«ng cÇn l©u). ultrasonication sãng siªu ©m xem: sonication.UMP ViÕt t¾t cña (ribo)nucleotide uridine 5'-monophosphate. Xem:uridylic acid. understock Host plant for a grafted scion, a branch or shoot from another plant; an understock may be a fully grown tree or a stump with a living root system.gèc ghÐp C©y chñ mang chåi ghÐp, mét nh¸nh hoÆc chåi cña c©y kh¸c;mét gèc ghÐp cã thÓ lμ c©y sinh tr-ëng ®Çy ®ñ hoÆc mét gèc ®èn cã bé rÔ khoÎ. undifferentiated Undifferentiated cells are those which have not been committed to become part of a specialized tissue.kh«ng ph©n hãa C¸c tÕ bμo kh«ng ®-îc biÖt hãa lμ tÕ bμo kh«ng ®-îc giao phã ®Ótrë thμnh bé phËn cña mét m« chuyªn dông.unencapsidated A virus not enclosed by a coat protein or capsid.thiÕu vá bäc Mét virut kh«ng ®-îc bäc bëi mét protein phñ ngoμi hoÆc vá bäc. unequal crossing over Abnormal meiotic event, in which one chromatid contains a duplication and the other a deletion. Often arises in a region containing repeated DNA sequences, which can pair out of register.lai chÐo kh«ng c©n b»ng Sù kiÖn gi¶m ph©n dÞ th-êng, trong ®ã mét nhiÔm s¾c töcã chøa sù nh©n ®«i vμ mét nhiÔm s¾c tökh¸c ®øt ®o¹n. Th-êng xuÊt hiÖn trong mét vïng chøa tr×nh tù DNA lÆp, nã cã thÓcÆp ®«i ngoμi ph¹m vi.unicellular Tissues, organs or organisms consisting of a single cell.®¬n bμo C¸c m«, c¬ quan hoÆc sinh vËt gåm cã tÕ bμo ®¬n.uniparental inheritance The inheritance of genes exclusively from one parent, e.g.c hloroplast DNA is inherited either maternally (many angiosperms) or paternally (most gymnosperms).di truyÒn mét cha/mÑ Di truyÒn cña nh÷ng gen chØ riªng tõ mét cha/mÑ, vÝ dôDNA lôc l¹p ®-îc di truyÒn theo mÑ (nhiÒu c©y h¹t kÝn) hoÆc theo cha (hÇu hÕt c©y h¹t trÇn).unisexual Higher organisms (animals or plants) possessing either male or female reproductive organs, but not both.®¬n tÝnh C¸c sinh vËt bËc cao (c©y trång vμ vËt nu«i ) cã c¬ quan sinh s¶n ®ùc hoÆc lμ c¸i, nh-ng kh«ng gåm c¶ hai. univalent An unpaired chromosome at the first division of meiosis.hãa trÞ mét NhiÔm s¾c thÓ kh«ng cÆp ®«i t¹i ph©n chia gi¶m ph©n lÇn ®Çu. universal donor c ell Cells that, after introduction into a recipient, will not induce an immune response that leads to their rejection.tÕ bμo cho phæ qu¸t Nh÷ng tÕ bμo mμ, sau khi chuyÓn vμo thÓ nhËn, sÏ kh«ng t¹o ra ph¶n øng miÔn dÞch mμ dÉn ®Õn th¶i bá chóng.universality Referring to the genetic code, the triplet codon s are translated to the same amino acid, with minor exceptions, in virtually all species.sù phæ qu¸t §Ò cËp ®Õn côm m· di truyÒn, c¸c côm m· bé ba ®-îc dÞch cho cïng mét293lo¹i amino acid, cã nh÷ng ngo¹i lÖ sai sãt nhá, trong hÇu nh- tÊt c¶ c¸c loμi. unorganized growth In vitro formation of tissues with few differentiated cell types and no recognizable structure; typical structure of calli formed in tissue culture. Opposite: organized growth.t¨ng tr-ëng thiÕu tæ chøc Trong èng nghiÖm sù h×nh thμnh m« víi mét Ýt kiÓu tÕbμo biÖt ho¸ vμ cÊu tróc kh«ng ®-îc nhËn biÕt;cÊu tróc ®iÓn h×nh cña m« sÑo h×nh thμnh trong nu«i cÊy m«. Ng-îc víi: organized growth.upstream 1. The stretch of DNA lying in the 5' direction from the site being considered. Where the reference point is the initiation of transcription, the first transcribed base is designated +1 and upstream nucleotides are marked with minus signs, e.g. -1, -10; 2. In chemical engineering, those phases of a manufacturing process that precede the biotransformation step. Refers to the preparation of raw materials for a fermentation process. Also called upstream processing.ng-îc dßn g 1. D·y DNA n»m theo h-íng 5' tõ vÞ trÝ ®ang xem xÐt. N¬i ®iÓm xem xÐt lμ b¾t ®Çu phiªn m·, ba z¬ ®-îc phiªn m·®Çu tiªn ®-îc chØ ®Þnh +1 vμ nh÷ng nuleotit ng-îc dßng ®-îc ®¸nh dÊu trõ, vÝ dô -1, -10; 2. Trong kü thuËt hãa häc, c¸c pha cña qu¸ tr×nh s¶n xuÊt tr-íc b-íc biÕn ®æi sinh häc. §Ò cËp chÕ phÈm nguyªn liÖu t-¬i sèng cña qu¸ tr×nh lªn men. Còng gäi lμxö lý ng-îc dßng.upstream processing xö lý ng-îc dßng xem: upstream (2).uracil (Abbreviation: U). One the bases found in RNA. See: uridine.uracil(viÕt t¾t: U).Mét lo¹i ba z¬ cã trong RNA. Xem: uridine.uridine The (ribo)nucleoside resulting from the combination of the base uracil (U) and the sugar D-ribose. See: uridylic acid, uridine triphosphate.uridin (ribo)nucleosit do kÕt hîp gi÷a ba z¬ uracil (U) vμ ®-êng D - riboza. xem: axit uridylic, uridine triphosphate.uridine triphosphate(uridine 5'-triphosphate) (Abbreviation: UTP). Required for RNA synthesis since it is a direct precursor molecule. See: uridylic acid.uridin ba phèt ph¸t (viÕt t¾t: UTP). CÇn thiÕt ®Ó tæng hîp RNA v× lμ mét ph©n tötiÒn chÊt trùc tiÕp. Xem: uridylic acid. uridylic ac id Synonym for uridine 5'-monophosphate (abbreviation: UMP), a (ribo)nucleotide containing the base uracil. See: uridine triphosphate.axit uridylic Tõ ®ång nghÜa uridin 5'-monophosphat (viÕt t¾t: UMP), mét (ribo)nucleotit chøa ba z¬ uracil. xem: uridine triphosphate.utilization of farm animal genetic resources The use and development of animal genetic resources for the production of food in a sustainable system of agriculture.sö dông tμi nguyªn gen ®éng vËt n«ng nghiÖp Sö dông vμ sù ph¸t triÓn tμi nguyªn di truyÒn ®éng vËt ®Ó s¶n xuÊt l-¬ng thùc trong hÖ thèng n«ng nghiÖp bÒn v÷ng.UTP Xem:uridine triphosphate.unorganized growth294V vV region Variable region in antibodies. See: CDR.vïng V Vïng biÕn ®æi cña kh¸ng thÓ. Xem: CDR.v/v Abbreviation for volume per volume. The relative proportion of each liquid in a mixture.tØ lÖ v/v ViÕt t¾t cña thÓ tÝch/thÓ tÝch. TØ lÖt-¬ng ®èi cña mçi chÊt láng trong mét hçn hîp.vaccination tiªm chñng Xem: preventive immunization.vaccine A preparation of dead or attenuated (weakened) pathogens, or of derived antigenic determinants, that can induce the formation of antibodies in a host, and thereby produce host immunity against the pathogen. See: sub-unit vaccine, viral vac c ine, DNA vac c ine, inoculum.v½c xin ChÕ phÈm cña c¸c vËt g©y bÖnh chÕt hoÆc lμm yÕu (suy nh-îc), hoÆc cña c¸c yÕu tè quyÕt ®Þnh kh¸ng nguyªn t¹o thμnh, mμ cã thÓ thóc ®Èy h×nh thμnh kh¸ng thÓ trong vËt chñ, vμ do ®ã s¶n xuÊt tÝnh miÔn dÞch vËt chñ chèng l¹i vËt g©y bÖnh. Xem: sub-unit vaccine, viral vaccine, DNA vaccine, inoculum.Vaccinia The cowpox virus used to vaccinate against smallpox and, experimentally, as a carrier of genes for antigenic determinants cloned from other disease organisms.ng-u ®Ëu Virut bÖnh ®Ëu bß dïng ®Ó tiªm chñng chèng l¹i bÖnh ®Ëu mïa vμ, ®-îc thùc nghiÖm, khi mét thÓ mang gen cho c¸c yÕu tè quyÕt ®Þnh kh¸ng nguyªn nh©n dßng tõ sinh vËt mang bÖnh kh¸c.vacuole A fluid-filled membrane-bound cavity inside many plant cells, in which various plant products and by-products are stored.kh«ng bμo Mét hèc h×nh thμnh mμng chøa ®Çy dÞch láng cã trong nhiÒu tÕ bμo thùc vËt, trong ®ã c¸c lo¹i s¶n phÈm thùc vËt vμ c¸c s¶n phÈm phô ®-îc cÊt tr÷. variable domain Regions of antibody molecules that have different amino acid sequences in different antibody molecules. These regions are responsible for the antigen-binding specificity of the antibody. miÒn biÕn Vïng ph©n tö kh¸ng thÓ cã tr×nh tù amino acid kh¸c nhau trong c¸c ph©n tö kh¸ng thÓ kh¸c biÖt. C¸c vïng nμy cãvai trß liªn kÕt kh¸ng nguyªn ®Æc hiÖu cña kh¸ng thÓ.variable expressivity Variation in the phenotype caused by different alleles of the same gene and/or by the action of other genes and/or by the action of non-genetic factors.biÓu thÞ biÕn dÞ BiÕn dÞ trong kiÓu h×nh g©y ra bëi nh÷ng alen kh¸c biÖt cña cïng mét gen vμ/hoÆc do ho¹t ®éng cña nh÷ng gen kh¸c vμ/hoÆc do ho¹t ®éng cña c¸c nh©n tè kh«ng di truyÒn.variable number tandem repeat (Abbreviation: VNTR). A DNA sequence, present as tandem repeats, for which the number of copies varies greatly between unrelated genotypes.lÆp kiÓu cÆp ®«i sè biÕn (viÕt t¾t: VNTR). Tr×nh tù DNA, cã mÆt c¸c lÆp l¹i kiÓu cÆp ®«i, v× thÕ sè l-îng c¸c b¶n sao thay ®æi lín gi÷a c¸c kiÓu gen kh«ng quan hÖ. variable surface glycoprotein (Abbreviation: VSG). One of a battery of antigenic determinants expressed by a micro-organism to elude immune detection.glicoprotein mÆt biÕn(viÕt t¾t: VSG).Mét trong bé nguån c¸c yÕu tè quyÕt ®Þnh kh¸ng nguyªn ®-îc biÓu thÞ do mét vi sinh vËt ®Ó tr¸nh dß t×m miÔn dÞch.295variance A statistical term representing a measure of the dispersion of data from the overall mean. Used to quantify the variability of a population.ph-¬ng sai ThuËt ng÷ thèng kª m«t¶Ótung b×nh ®é ph©n t¸n cña d÷ liÖu tõtoμn bé phÐp ®o. Dïng x¸c ®Þnh sè l-îng biÕn thiªn cña mét quÇn thÓ.variant An individual that is genetically distinct from others in the population.biÕn thÓMét c¸ thÓ mμ kh¸c kiÓu di truyÒn víi c¸c c¸ thÓ kh¸c trong quÇn thÓ. variation Differences between individuals within a population or among populations. biÕn dÞ Sù kh¸c nhau gi÷a nh÷ng c¸ thÓtrong mét quÇn thÓ hoÆc gi÷a c¸c quÇn thÓ.variegation The occurrence, within a single tissue, organ or organism, of mosaicism. Usually referring to plants showing either both green and albino colouration in a leaf, or flecks of contrasting colour in a flower. The origin of variegation can be through viral infection, nutritional deficiency, or genetic instability caused by transposon activity. See also: chimera biÕn kh¶m BiÕn cè, bªn trong mét m« ®¬n, c¬ quan hoÆc sinh vËt, cña hiÖn t-îng kh¶m. Th-êng liªn quan víi c¸c thùc vËt cho thÊy c¶ mμu xanh lôc vμ mμu b¹ch t¹ng trong mét l¸ c©y, hoÆc nh÷ng ®èm s¸ng mμu t-¬ng ph¶n cña mét hoa. Nguån gèc biÕn ®æi kh¶m cã thÓ qua nhiÔm virut, thiÕu hôt dinh d-ìng, hoÆc tÝnh kh«ng æn ®Þnh di truyÒn g©y ra bëi ho¹t ®éng gen nh¶y. Xem: chimeravariety 1. A naturally occurring subdivision of a species, with distinct morphological characters. 2. A defined strain of a crop plant, selected on the basis of phenotypic (sometimes genotypic) homogeneity.thø loμi1. Sù chia nhá x¶y ra tù nhiªn cña loμi, víi c¸c ®Æc tr-ng h×nh th¸i ph©n biÖt. 2. Chñng x¸c ®Þnh cña mét gièng c©y trång, lùa chän trªn c¬ së di truyÒn ®ång nhÊt kiÓu h×nh (®«i khi lμ kiÓu gen). vascular Plant tissue specialized for the conduction of water or nutrients m¹ch M« thùc vËt chuyªn dïng ®Ó dÉn n-íc hoÆc chÊt dinh d-ìngvasc ular bundle A strand of tissue containing primary xylem and primary phloem (and procambium if present) and frequently enclosed by a bundle sheath of parenchyma or fibres.bã m¹ch Sîi m« chøa thí gç s¬ cÊp vμlibe s¬ cÊp (vμ tiÒn t-îng tÇng nÕu cã) vμth-êng xuyªn ®-îc bao bäc bëi mμng bäc xung quanh nhu m« hoÆc sîi.vasc ular c ambium In biennials and perennials, cambium giving rise to secondary phloem and secondary xylem.tÇng ph¸t sinh m¹ch Trong c¸c c©y hai n¨m vμ c©y l©u n¨m, tÇng ph¸t sinh t¹o ra libe thø cÊp vμ thí gç thø cÊp.vascular plant Plant species possessing organized vascular tissues.thùc vËt cã m¹ch C¸c loμi thùc vËt lu«n cã c¸c m« m¹ch ®-îc tæ chøc.vascular system 1. A specialized network of vessels for the circulation of fluids throughout the body tissue of an animal.2. The system of vascular tissue in plants. hÖ m¹ch, hÖ dÉn 1.M¹ng èng m¹ch chuyªn dông ®Ó l-u hμnh c¸c chÊt láng qua kh¾p c¸c m« c¬ thÓ ®éng vËt. 2. HÖthèng m« m¹ch cña thùc vËt.vector 1. An organism, usually an insect, that carries and transmits pathogens. 2.A small DNA molecule (plasmid, virus, bacteriophage, artificial or cut DNA molecule) that can be used to deliver DNA into a cell. Vectors must be capable of being replicated and contain cloning sites for the introduction of foreign DNA.vect¬ 1. Mét sinh vËt, th-êng lμ c«n trïng mμ cã mang vμ truyÒn dÉn vËt g©y bÖnh.2. Mét ph©n tö DNA nhá (plasmit, virut, thÓthùc khuÈn, ph©n tö DNA nh©n t¹o hoÆc c¾t ®o¹n) cã thÓ dïng ®Ó chuyÓn giao DNA cho tÕ bμo. C¸c vect¬ cÇn ph¶i cã kh¶n¨ng xo¾n l¹i vμ chøa c¸c vÞ trÝ t¹o dßng nhÊt ®Þnh ®Ó chuyÓn DNA l¹.vegetative propagation sinh s¶n sinh d-ìng Xem: asexual propagation.variance296velocity density gradient centrifugation A procedure used to separate macromolecules based on their rate of movement through a density gradient.ly t©m møc ®é mËt ®é vËn tèc Ph-¬ng ph¸p dïng ®Ó t¸ch c¸c ®¹i ph©n tö dùa vμo nhÞp ®é chuyÓn ®éng cña chóng th«ng qua gradient mËt ®é.velogenetics The combined use of marker-assisted selection and embryo technologies such as OPU, IVM and IVF, in order to increase the rate of genetic improvement in animal populations. velogenetic ViÖc sö dông kÕt hîp chän läc cã hç trî dÊu chuÈn vμ c«ng nghÖ ph«i nh- lμ OPU, IVM vμ IVF, ®Ó t¨ng thªm nhÞp ®é c¶i thiÖn gen cña quÇn thÓ ®éng vËt. vermiculite Material made from expanded mica used as a rooting medium and as a soil additive.ermiculit VËt chÊt lμm tõ mica ®-îc mëréng dïng lμm m«i tr-êng -¬m rÔ vμ phôgia ®Êt.vernalization Chilling juvenile plants for a minimum period in order to induce flowering. Some plants require ve RNA lization to flower, but others have no such requirement.xu©n hãa Thùc vËt non ch-a ph¸t triÓn lμm l¹nh mét giai ®o¹n tèi thiÓu víi môc ®Ých thóc ®Èy ra hoa. Mét sè thùc vËt yªu cÇu xu©n hãa ®Ó ra hoa, nh-ng mét sèkh¸c kh«ng cã yªu cÇu nh- vËy.vessel A series of xylem elements whose function is to conduct water and nutrients in plants.èng m¹ch Mét lo¹t c¸c phÇn tö thí gç cãchøc n¨ng dÉn n-íc vμ chÊt dinh d-ìng trong thùc vËt.vessel element A type of cell occurring within the xylem of flowering plants. Many are water-conducting vessels.phÇn tö èng m¹ch Mét kiÓu tÕ bμo xuÊt hiÖn trong m¹ch gç cña thùc vËt ra hoa. NhiÒu phÇn tö èng m¹ch lμ c¸c èng dÉn n-íc.viability The capability to live and develop normally.kh¶ n¨ng sinh tån Kh¶ n¨ng ®Ó sèng vμph¸t triÓn b×nh th-êng.viability test Assay of the number or percent of living cells or plants in a population following a specific treatment. Often used to describe quality of seed following long-term storage.thö kh¶ n¨ng sèng Thö nghiÖm sè l-îng hoÆc phÇn tr¨m tÕ bμo hoÆc thùc vËt sèng trong mét quÇn thÓ theo mét ph-¬ng ph¸p riªng. Th-êng dïng ®Ó m« t¶ chÊt l-îng h¹t gièng sau b¶o qu¶n dμi h¹n.viable Capable of normal completion of life cycle.cã kh¶ n¨ng sèng Kh¶ n¨ng hoμn thμnh b×nh th-êng chu tr×nh sèng.vibrio Comma-shaped bacterium.vi khuÈn phÈy Vi khuÈn cã h×nh d¹ng dÊu phÈy.vir genes A set of genes on a Ti plasmid that prepare the T-DNA segment for transfer into a plant cell.gen vir TËp hîp gen trªn mét Ti plasmit ®Ó chuÈn bÞ ®o¹n c¾t T-DNA chuyÓn cho tÕ bμo thùc vËt.viral coat protein A protein present in the layer surrounding the nuc leic ac id core of a virus.protein phñ virut Protein cã mÆt trong líp xung quanh lâi axit nucleic cña virut. viral oncogene A viral gene that promotes tumour development in a host.gen g©y ung th- virut Mét gen virut thóc ®Èy ph¸t triÓn khèi u trong vËt chñ.viral pathogen A disease-causing virus. vËt g©y bÖnh virut Mét virut g©y bÖnh. viral vac c ine Vaccine consisting of live viruses, genetically engineered to avoid causing the disease itself.vacxin virut Vacxin gåm cã virut sèng,®-îc kÜ thuËt gen ®Ó tr¸nh tù g©y ra bÖnh h¹i.velocity density gradient centrifugation297virion A complete infectious virus particle. h¹t ®éc H¹t virut l©y nhiÔm hoμn chØnh. viroid A plant pathogenic agent, composed of an infectious single-stranded low molecular weight RNA, and no c oat protein.thÓ vi rót T¸c nh©n g©y bÖnh thùc vËt, gåm cã RNA ph©n tö l-îng thÊp sîi ®¬n cã kh¶ n¨ng l©y nhiÔm, vμ kh«ng cã protein vá bäcvirulence The degree of ability of an organism to cause disease. The relative infectiousness of a bacterium or virus, or its ability to overcome the resistance of the host metabolism.tÝnh ®éc Møc ®é kh¶ n¨ng cña sinh vËt ®Ó g©y bÖnh h¹i. Sù nhiÔm ®éc t-¬ng ®èi cña vi khuÈn hoÆc virut, hoÆc kh¶ n¨ng ®ÓchiÕn th¾ng tÝnh kh¸ng cña sù chuyÓn ho¸vËt chñ.virulent phage A phage that destroys its host bacterium.thùc khuÈn ®éc Mét thùc khuÈn thÓ ph¸hñy vi khuÈn chñ.viruliferous A vector (usually insect) organism that carries virions and spreads the virus from host to host by mechanical means.chøa virut Sinh vËt vect¬ (th«ng th-êng lμ c«n trïng) mang h¹t ®éc vμ chuyÓn virut tõ ký chñ ®Õn ký chñ b»ng ph-¬ng ph¸p c¬ häc.virus An infectious particle composed of a protein capsule and a nucleic acid core (DNA or RNA), which is dependent on a host organism for replication.vi rót H¹t l©y nhiÔm gåm cã mét vá bäc protein vμ mét lâi axit nucleic (DNA hoÆc RNA), nã dùa vμo sinh vËt chñ ®Ó sao chÐp.virus-free P lant, animal, cell, tissue or meristem which exhibits no viral symptoms or contains no identifiable virus particles.s¹ch virut Thùc vËt, ®éng vËt, tÕ bμo, m«hoÆc m« ph©n sinh biÓu hÞªn nh÷ng triÖu chøng kh«ng cã virut hoÆc chøa nh÷ng h¹t virut kh«ng thÓ nhËn biÕt.virus-tested Description of a organism or a cell stock certified as being free of certain specified virus es following recognized procedures of virus diagnosis.kiÓm tra virut M« t¶ mét sinh vËt hoÆc mét tæ tÕ bμo ®-îc chøng nhËn lμ s¹ch virut ®-îc ghi chÐp cô thÓ tiÕp theo sau c¸c thñ tôc ghi nhËn chÈn ®o¸n virut. vitamin Naturally occurring organic substance required by living organisms in small amounts to maintain normal health. vitamin ChÊt h÷u c¬ xuÊt hiÖn tù nhiªn do sinh vËt sèng yªu cÇu víi sè l-îng nhá ®Óduy tr× søc kháe b×nh th-êng.vitrified Cultured tissue having leaves and sometimes stems with a glassy, transparent or wet and often swollen appearance. The process of vitrification is a general term for a variety of physiological disorders that lead to shoot tip and leaf necrosis. Synonym: water soaked.ho¸ thuû tinh M« ®-îc nu«i cÊy mang l¸vμ ®«i khi lμ th©n cã vÕt trong mê, trong suèt hoÆc Èm -ít vμ lu«n xuÊt hiÖn s-ng phång. Qu¸ tr×nh hãa thñy tinh lμ mét thuËt ng÷ chung chØ mét d¹ng rèi lo¹n sinh lýdÉn tíi chøng ho¹i tö ®Ønh chåi vμ l¸ non. Tõ ®ång nghÜa: water soaked. viviparous thuéc sinh con(tÝnh tõ) Xem: vivipary.vivipary 1. A form of reproduction in animals in which the developing embryo obtains its nourishment directly from the mother via a placenta or by other means.2. A form of asexual reproduction in certain plants, in which the flower develops into a bud-like structure that forms a new plant when detached from the parent.3. The development of young plants in the inflorescence of the parent plant.sinh con 1.D¹ng sinh s¶n cña ®éng vËt trong ®ã ph«i ph¸t triÓn hÊp thu thøc ¨n trùc tiÕp tõ mÑ qua mét rau thai hoÆc b»ng c¸c ph-¬ng c¸ch kh¸c. 2. D¹ng sinh s¶n v« tÝnh trong thùc vËt nhÊt ®Þnh, trong ®ãvirion298hoa ph¸t triÓn thμnh mét cÊu tróc gièng nh- chåi nô ®Ó h×nh thμnh c©y míi khi ®-îc t¸ch khái c©y mÑ. 3. P h¸t triÓn cña c¸c c©y non trong hoa cña c©y mÑ.V max The maximal rate of an enzyme-catalysed reaction. V max is the product of E o (the total amount of enzyme ) and K cat (the catalytic rate constant).V max Tèc ®é tèi ®a cña mét ph¶n øng xóct¸c enzim. V max lμ s¶n phÈm cña E o(toμn bé sè l-îng enzim)vμ K cat (h»ng sè tèc ®é xóc t¸c).VNTR vi Õt t¾t cña variable number tandem repeat .volatilization The conversion of a solid or liquid into a gas or vapour.th¨ng hoa Sù chuyÓn ®æi cña chÊt r¾n hoÆc chÊt láng thμnh khÝ hoÆc h¬i.VSG Vi Õt t¾t cña variable surfac e glycoprotein .V max。

英语7 Unit4 Civilization

12/23/2013
Tick out the things which our ancestors used to write on before paper was invented. Then read through the text quickly to check your answers.
12/23/2013
e.g. I am determined to work hard and make progress day by day. He is determined to win the English composition contest.
A court official named Cai Lun was determined to develop a new and better writing material. He used bark, hemp, rags and old fishing nets as possible ingredients. First, he cut all his raw materials into small pieces and then pounded them into a paste or pulp. This thin layer of pulp was then dried on a piece of fine cloth. When it dried completely, it was paper. It was thin and light, inexpensive to make and quite durable.
12/23/2013
பைடு நூலகம்
accomplish
accomplishment

Unit 7 Oliver Wants MorePowerPoint 演示文稿

7. What was Oliver supposed to do?
To ask for more.
.
1F~N
How many leading characters are mentioned in the parts? Who are they?
The master
Mr. Bumble
After Oliver asked for more---------- Para __O__
.
7
Scan Para. A~C and answer the questions
1. Where and with whom did Oliver live?
2. What were the rules made by the board of management?
.
2
Notable works by Charles Dickens
• 1. The Pickwick Papers 《匹克威克外传》--( April 1836 to November 1837)
• 2. Oliver Twist
《雾都孤儿》— 18371839
• 3. A Christmas Carol 《圣诞颂歌》 --- 1843
.
10
Oliver’s___se_v_e_re__ Life in the workhouse
hard , difficult ,terrible
6. What was one boy afraid?
He was afraid that he might some night eat the boy who slept next to him.
7. What was Oliver supposed to do?

英语文献

Probabilistic analysis of time-dependent de¯ections ofRC ¯exural membersE.H.Khor a,1,D.V.Rosowsky a,b,*,M.G.Stewart caDepartment of Civil Engineering,Clemson University,Clemson,SC,USAbDepartments of Forest Products and Civil Engineering,Oregon State University,Corvallis,OR 97331-5751,USA cDepartment of Civil,Surveying,and Environmental Engineering,University of Newcastle,NSW 2308,AustraliaReceived 25April 2000;accepted 7May 2001AbstractThis paper presents a procedure for the probabilistic analysis of time-dependent de¯ection of a reinforced concrete ¯exural member subject to a time-varying load process.Particular consideration is given to simply supported,singly reinforced rectangular beams.The algorithm takes into account concrete maturation,nonlinear creep and shrinkage behavior,and stochastic load process models for both construction and service.While this paper describes some practical implications of early-age e ects (i.e.,high early-age construction loads on immature concrete)for serviceability design,the emphasis of this paper is on the probabilistic time-dependent de¯ection analysis technique.Ó2001Elsevier Science Ltd.All rights reserved.Keywords:Construction loads;Creep;De¯ection;Early-age e ects;Flexural members;Probabilistic de¯ection analysis;Reinforced concrete;Serviceability;Shrinkage;Time-dependent behavior1.IntroductionThe reliability of reinforced concrete members and systems has been the focus of a considerable amount of research.However,most studies have focused on ulti-mate strength,rather than serviceability limit states [6±12,14,16,20,21,24,31,38].Reliability-based design has formed the basis for the strength provisions in modern reinforced concrete design codes.By contrast,service-ability provisions for reinforced concrete design have not evolved from such reliability bases.With the advent of limit state design has come a trend toward a more economic proportioning of members (i.e.,longer andmore slender members),serviceability problems such as excessive de¯ection have become more prevalent [34].As performance problems continue to be identi®ed in exi-sting (and aging)concrete structures,the development of e ective serviceability design provisions has become even more important for life-cycle design.To date,very few reliability-based de¯ection design provisions have been developed,and these have pri-marily been for structural steel and timber [13,32].The de¯ection design provisions for reinforced concrete in most building codes,e.g.,the ACI 318-95building code [4],are still based on an elastic analysis and a time-independent approach (i.e.,elastic de¯ection increased by an empirical factor to account for creep and shrink-age e ects).These provisions are mostly empirical and do not always provide a good estimate of time-varying de¯ections.This is not particularly surprising since the problem of time-dependent de¯ection analysis for RC members is more complicated than for other materi-als due to the viscoelastic material behavior (includ-ing concrete maturation,creep and shrinkage e ects).Further computational di culties arise incalculatingComputers and Structures 79(2001)1461±1472/locate/compstruc*Corresponding author.Address:Departments of Forest Products and Civil Engineering,Oregon State University,Corvallis,OR 97331-5751,USA.Tel.:+1-541-737-8422;fax:+1-541-737-3386.E-mail address:david.rosowsky@ (D.V.Rosow-sky).1Now at:ANSYS,Inc.,Canonsburg,PA 15316,USA.0045-7949/01/$-see front matter Ó2001Elsevier Science Ltd.All rights reserved.PII:S 0045-7949(01)00047-5time-dependent de¯ections and probabilities of ser-viceability failure[24],especially when considering a time-varying load process.Li and Melchers[19]were among the®rst to develop an approach for evaluating the time-dependent de¯ection limit state probabilities for reinforced concrete¯exural members considering viscoelastic response model and time-varying load pro-cess.Stewart[36]later developed a more detailed proba-bilistic de¯ection model for assessing the e ectiveness of current design speci®cations.However,these models are strain based(with strains determined from stresses) and may not be highly e cient for a time-dependent analysis in which the stresses vary,even under a con-stant applied load,due to creep and shrinkage e ects.In the present study,a more e cient curvature-basedapproach(determined from moments)is introduced and is used in a probabilistic time-dependent de¯ection analysis of a multi-pulse process[18].Results from the analysis can be used to evaluate early-age e ects(i.e.,the combination of high early-age construction loads on immature concrete)on long-term de¯ection of realisti-cally designed,simply-supported RC¯oor beams,such as might be found in a multistory o ce building.A re-alistic construction load process model,an extension of a deterministic model developed by Chen and Mosallam [5],was developed as part of this study.This model also takes into account the time-dependent strength and sti ness gain in ing this construction load process model,two of the most widely used construction procedures,i.e.,three levels of shores(3S),and two levels of shores and one level of reshores(2S1R),are consid-ered.The building lifetime is divided into the construc-tion period(6±24months),and the service or occupancy period(typically50years in the US).The probabilistic analysis framework includes the following components: (i)construction load model,(ii)service-life load model, (iii)elastic,creep and shrinkage models,(iv)maturation model for concrete material properties,(v)time-depen-dent analysis technique(age-adjusted elastic modulus method,AEMM),(vi)tension sti ening model,(vii)su-perposition procedure and(viii)maximum de¯ection analysis model.Since the parameters for loading,con-crete material properties,member dimensions,reinforcing steel properties,environmental conditions and modeling uncertainties are modeled as random variables,or time-dependent variables,or both,a closed-form analysis procedure is not tractable.Thus,Monte-Carlo simula-tion is used to determine the elastic,creep and shrinkage components of de¯ection with time,and superposition is used to evaluate the total de¯ection responses.2.Time-dependent analysis techniqueThe analysis of the time-dependent behavior of a reinforced concrete member requires knowledge of strains,stresses and curvatures along the member.These quantities are all time dependent as a result of the combined e ects of concrete maturation,creep and shrinkage under a time-varying loading process.The time-dependent de¯ection at location z along the mem-ber(see Fig.1)can be determined by double integrating the curvature over the length from the origin to the location of interest as follows:d zZ zZ zj x;t d x d x 1where d z is the de¯ection at location z and j x is the curvature at any location x along the member.An ac-curate calculation of de¯ection can be computationally very intensive since the curvature is a function of both location x and time t.This procedure,however,can be simpli®ed by determining only the curvatures at a pre-determined number of critical points along the member. With an assumption of parabolic variation between adjacent points,the maximum de¯ection that occurs at the midspan of a simply supported member can be ap-proximated as:d C%L296j A 10j C j B 2where A and B are the locations of the simple supports, and C is the midpoint of the beam(see Fig.2);j A,j B and j C are the curvatures at points A,B and C,re-spectively;and L is the length of the member.In this study,the cross-sectional analysis technique known as the AEMM,speci®cally the AEMM Approach II, [15,18],is extended to be able to evaluate the time-dependent curvatures under a multi-pulse loading process.For a multi-pulse process as shown in Fig.3,the time-varying loads can be decomposed into individual load increments as illustrated in Fig.4.Under the as-sumption of linear behavior(i.e.,generally assumed for stress<0.5f H c in concrete),the total response at any point of the simply-supported member at any time can be determined by superimposing the individualresponses Fig.1.Generalized de¯ected shape of an end-constrained member.1462 E.H.Khor et al./Computers and Structures79(2001)1461±1472due to the individual load increments.According to the principle of superposition,the total curvature at point C located at the midspan caused by the applied loads (moments),creep and shrinkage e ects can therefore be determined as:j C X ij elas : t i X ij cre : t ;t i j shrin : t ;t 0 3where t ,t i and t 0are the time at which the de¯ection is to be determined,the time of application of load increment i ,and the time at the start of drying,respectively.Note that,t 06t 1since load is normally not applied during curing.The curvatures j elas : t i ,j cre : t ;t i and j shrin : t ;t 0 are the elastic curvature caused by load increment i ,the creep-induced curvature caused by load increment i for time interval t Àt i ,and the shrinkage-induced curva-ture during time interval t Àt 0 ,respectively.Note that shrinkage-induced curvature is independent of applied load.Since the member is simply supported at both ends,and the curvatures at points A and B are caused only by shrinkage e ects (i.e.,they are load indepen-dent),the curvatures can be expressed as:j A j B j shrin : t ;t 04By substituting Eqs.(3)and (4)into Eq.(2),the midspan de¯ection can be rewritten as:d C t %L29610Xij elas : t i ("Xij cre : t ;t i)12j shrin : t ;t 0#5The change in elastic curvature j elas : t i caused by ap-plied load increment i can be determined as j elas : t iA t i M t iB t i N t i E c t i A t i I t i ÀB t i 26where A t i ,B t i and I t i are the area moment,®rst moment,and second moment of the transformed cross-section at time t i all taken about the top ®ber of the member cross-section,respectively;M t i is the applied moment at time t i ,i.e.,M t i D M i (see Figs.3and 4);N t i is the applied axial force at the level of steel at time t i (N t i 0for the beam subject to transverse load only,as is considered herein).For the member cross-section shown in Fig.5,the sectional properties of A t i ,B t i and I t i at time t i are given by:A t i bd n t i n t i A s A ct t i7 B t i 12bd 2n t i n t i A s d A ct t i d 8 I t i 13bd 3n t i n t i A s d 2 A ct t i d 2 9where b is the cross-section width,A s is the steel area,d is the e ective depth,and d n t i is the depth of the neutral axis at time t i determined as:d n t i 2q n m t i f q n m t i g 2q Àq n m t id 10 where q is the steel ratio,q A s =bd .The modi®ed modular ratio for the tensile reinforcement,n m t i ,ac-counts for tension sti ening at time t i [15,18]and is givenby:Fig.2.De¯ected shape of a simply supportedmember.Fig.3.Discretization of a multi-pulse process.E.H.Khor et al./Computers and Structures 79(2001)1461±14721463n m t i n t iA ct t i s11where n t i is the modular ratio at time t i .This is cal-culated as:n t iE s E c t i12where E s is the elastic modulus of steel and E c t i is the elastic modulus of concrete at time t i calculated using the creep compliance function.E c t i1J t i D SD ;t i13The creep compliance term J t i D SD ;t i can be calcu-lated using any one of a number of available models,where D SD is stress duration.In this study,Bazant's B3creep model with D SD 0:001day [1±3]is used.TheFig.5.Singly reinforcedcross-section.Fig.4.Decomposition of a multi-pulse process.1464 E.H.Khor et al./Computers and Structures 79(2001)1461±1472term A ct t i is the tensile concrete area assumed to con-tribute to the member sti ness after cracking at time t i, and depends mainly on the magnitudes of applied mo-ment and cracking moment,the area of the tensile re-inforcement,the area of concrete below the neutral axis, and the tensile strength of the concrete.The tensile concrete area is determined as follows[15,18]:A ct t i b1b2 0:21bdÀn t i A sM cr t ii214where b1 1and0.5for deformed bars and round bars, respectively;b2 1and0.5for initial loading and long-term/cyclic loading,respectively;and M cr t i is the con-crete cracking moment at time t i,determined by:M cr t i bh2f r t i615where h is the total depth of the cross-section.Note that when M t i <M cr t i ,the ratio M cr t i =M t i is taken as unity.The time-dependent concrete tensile strength f r t i can be determined using one of a number of available models.In this study,Oluokun's model is used[30]:f r t i 1:38f H c t i 0:69 16This model was developed using a large amount of experimental data covering a wide range of concrete maturation times.In Eq.(16),f H c t i is the concrete compressive strength at time t i given by:f H c t iE c t i57000217Note that Eqs.(16)and(17)are in units of psi.The creep-induced curvature caused by load incre-ment i for time interval tÀt i can be evaluated using the AEMM as follows[15,18]:j cre: t;t i A e t;t i M creep t;t i B e t;t i N creep t;t iE e t;t i A e t;t i I e t;t i ÀB2e t;t i18where E e t;t i is the age-adjusted e ective modulus to account for creep e ects during the time interval tÀt i calculated as:E e t;t iE c t i1 v t;t i / t;t i19where v t;t i is the time-dependent concrete aging coef-®cient for the time interval tÀt i .A value of v t;t i 0:8can be assumed for most practical purposes[29].The term/ t;t i is the creep coe cient for the time interval tÀt i .The section moments of the age-adjusted trans-formed cross-section for the time interval tÀt i are determined as:A e t;t i bd n t i n e t;t i A s A ct t i 20B e t;t i 12bd2n t i n e t;t i A s d A ct t i d 21I e t;t i 13bd3n t i n e t;t i A s d2 A ct t i d2 22 where n e t;t i is the age-adjusted modular ratio for the time interval tÀt i calculated by:n e t;t iE sE e t;t i23The terms M creep t;t i and N creep t;t i in Eq.(18)are the®ctitious moment and axial force that result from the creep e ects for time interval tÀt i and are calculated as follows[15,18]:ÀM creep t;t i ÀE e t;t i / t;t i A c t i e elas: t iÀB c t i j elas: t i 24 ÀN creep t;t i ÀE e t;t i / t;t i ÀB c t i e elas: t iÀI c t i j elas: t i 25 where A c t i ,B c t i and I c t i are the area,®rst and sec-ond moments of the concrete cross-section(ignoring steel)taken about the top®ber(since only the concrete is assumed to exhibit creep)calculated as:A c t i bd n t i 26B c t i 12bd2n t i 27I c t i 13bd3n t i 28 The top®ber elastic strain e elas: t i caused by the ap-plied load increment at time t i is given by:e elas: t iB t i M t i I t i N t iE c t i A t i I t i ÀB t i 229Unlike creep-induced curvature,shrinkage-induced curvature is only calculated once for the time interval tÀt0 since it is not load dependent.The shrinkage-induced curvature j shrin: t;t0 is evaluated as follows:j shrin: t;t0A e t;t0 M shrinkage t;t0B e t;t0 N shrinkage t;t0E e t;t0 A e t;t0 I e t;t0 ÀB2e t;t030 where A e t;t0 ,B e t;t0 and I e t;t0 are the area,®rst and second moments of the age-adjusted transformed cross-section for time interval tÀt0 ,respectively,given by:A e t;t0 bd n t0 n e t;t0 A s 31B e t;t0 12bd2n t0 n e t;t0 A s d 32I e t;t i 13bd3n t0 n e t;t0 A s d2 33E.H.Khor et al./Computers and Structures79(2001)1461±14721465The term d n t0 is the depth of the neutral axis at time t0 determined using Eq.(10); n e t;t0 is the age-adjusted modular ratio for the time interval tÀt0 ,calculated as:n e t;t0 sE e t;t034E e t;t0 is the age-adjusted e ective modulus for the timeinterval tÀt0 and is given by:E e t;t0E c t01 v t;t0 / t;t035The terms M shrinkage t;t0 and N shrinkage t;t0 in Eq.(30) are the®ctitious moment and axial force that result from the shrinkage e ects for time interval tÀt0 and are calculated as follows[15,18]:ÀM shrinkage t;t0 E e t;t0 e shrin: t;t0 B c t0 36ÀN shrinkage t;t0 ÀE e t;t0 e shrin: t;t0 A c t0 37 where Eshrint(t;t0)is the mean shrinkage strain of concrete for the interval(t;t0)and where A c t0 and B c t0 are the area and®rst moments of the concrete cross-section(ignoring steel)taken about the top®ber. As with creep,only the concrete is assumed to exhibit shrinkage.The section moments A c t0 and B c t0 are given by:A c t0 bd n t0 38B c t0 12bd2n t0 39 3.Probabilistic de¯ection analysis3.1.Structural memberTo illustrate this analysis procedure,a series of¯exu-ral members are analyzed herein.The structural mem-bers considered are singly reinforced,simply supported reinforced concrete rectangular beams designed ac-cording to ACI318-95[4]with a design o ce live load of50psf[25].All beams were designed to meet both the strength and serviceability provisions in ACI318-95. The concrete mix for a particular design concrete com-pressive strength was determined by the ACI Manual of concrete practice[23].For comparison purposes,a set of baseline conditions was established.A baseline beam span of25ft is assumed,the design concrete compressive strength at28days is taken as4000psi using Type-I Portland cement,and Grade60steel(modulus of elas-ticity of29000Â103psi)is assumed for the reinforcing bars.The complete list of baseline beam parameters used in the time-dependent analyses are shown in Table1. Only selected beam results are presented in this plete results,for both simply supported beams and one-way slabs,are presented elsewhere[18].3.2.Random parametersFor the de¯ection analyses considered herein,the random parameters can be grouped into four categories: (i)dimensional parameters,(ii)material property pa-rameters,(iii)modeling errors and(iv)applied load parameters.The dimensional parameters are those re-lated to the dimensions of the cross-section of a struc-tural element,e.g.,total depth,width,cover and steel area.The material property parameters include concrete compressive strength,modulus of elasticity of concrete, modulus of elasticity of steel and those associated with concrete mixing and curing(and hence the compressive strength),e.g.,relative humidity,water-cement ratio, cement content,water content,aggregate-cement ratio, and so forth.Modeling error terms are used to account for the uncertainty and inaccuracy of a model in pre-dicting a phenomenon.In the present study,modeling error terms are included for the creep coe cient and shrinkage strain models,respectively[1].The applied loads are those occurring during either the construction or service-life periods.The generalized construction load model used in the present study is shown in Fig.6,for both the3S and2S1R shoring plete descriptions of these models,along with discussions of assumptions and sources of loading statistics,are pre-sented elsewhere[18].Most parameters considered herein are treated as random variables to account for inherent statistical variability and/or phenomenological uncertainty.The relevant statistical moments and distributions assumed in the present study for the dimensional parameters,ma-terial property parameters[21,26±28],modeling errors and relative humidity[1]are summarized in Table2. The statistical moments,distributions and arrival rate Table1Design parameters for baseline beamConcrete mix for f H c 4000psic(lb/yd3)(cement content)647a=c(aggregate-cement ratio) 4.66s=c(sand-cement ratio) 1.77a(%)(air content) 1.00Slump(in.) 4.00Aggr.type gran. Geometric propertiesb(in.)16.0h(in.)29.0d(in.)26.5d H(in.) 2.5A s(in.2) 4.541466 E.H.Khor et al./Computers and Structures79(2001)1461±1472information for the di erent load types are summarized in Tables 3and 4.Sample functions of the 2S1R con-struction load process and the occupancy live load process are shown in Fig.7a and b,respectively.3.3.Monte-Carlo simulationMonte-Carlo simulation is used herein to generate sets of random variables that appear in the de¯ection function according to assumed statistical data and probability distributions.The mean and coe cient of variation (COV)of the de¯ections for a predetermined reference period are then calculated from a set of simu-lated responses.The number of simulation runs N s required to achieve results with acceptable accuracy is determined by evaluating the convergence behavior,as N s increases,of the statistical moments of the de¯ec-tions.Fig.8shows the mean and COVof the simulated 50-year maximum de¯ections of the baseline beam (subjected to 3S construction load scenario),respec-tively,as a function of N s .The mean and COVare seen to converge after about 1000simulation runs.It is therefore assumed that 1000simulation runs are su -cient to statistically characterize the maximum de¯ec-tions for the beams considered in this study.3.4.Sensitivity analysisA sensitivity analysis study is an important com-ponent in any probabilistic analyses and provides information about the relative signi®cance of system parameters on the calculated response.The time and cost of an analysis can be signi®cantly reduced if the variability of system parameters can be safely neglected.There are a variety of methods available for performing sensitivity analyses [17,22,33].In the present study,the relative signi®cance of a parameter is evaluated by treating that parameter as deterministic while all other parameters are treated as random variables,and com-paring the calculated response with that obtained as-suming all parameters are random.In this sensitivity analysis,the baseline beam subjected to a 50-year service load history is considered.Three quantities,the mean value,COVand 95th-percentile value,are used in the comparisons.The mean value alone cannot always pro-vide complete information on the relative signi®cance of each variable.A comparison of COVs can provide some indication of the relative sensitivity of a parame-ter.On this basis,the following variables were found to have the greatest e ect on the calculated de¯ection,in decreasing order of importance:concrete compres-sive strength f H c ,creep modeling error w 1 ,shrinkage modeling error w 2 and humidity h m .The same obser-vation was also made by comparing the 95th-percentile values.That is,the concrete compressive strength f H c is found to have the most signi®cant e ect on the calcu-lated response,followed by the creep modeling error w 1 ,shrinkage modeling error w 2 and humidity h m .These ®ndings are in general agreement with previous studies[22,36].Fig.6.Generalized construction load process for 3S and 2S1R construction operations.E.H.Khor et al./Computers and Structures 79(2001)1461±147214673.5.Baseline and parametric study resultsThe mean and COVof the de¯ections for the baseline beam for the three di erent loading cases are presented in Table 5.The probability density function (PDFs)are shown in Fig.9,for 1,8and 50years,considering the service load only and 2S1R construction load cases.The mean de¯ection for the service load only case increases over that for the one-year reference period by about 40%and 60%for reference periods of 8and 50years,re-spectively.The increases of de¯ections for 3S and 2S1R,however,are not as signi®cant as those for the service load only case.This suggests that the construction loads cause large early-age de¯ections.The relative impor-tance of early-age e ects can also be seen by comparing the mean values of the de¯ections for the cases with andTable 2Summary of random variables in baseline beam analysisMeanMean-to-nominal COVStd.dev.CDFTruncation,Bounds LowerUpper Geometric parameters b À0.12in.±±0.25in.Normal ±±h 0.10in.±±0.14in.Normal ±±d H 0.06in.±±0.44in.Normal 0.90in.±A s ±0.990.024±Normal 0.94in 2±Material parametersf H c 4000psi a3390psi ±0.18±Lognormal ±±E cVariable dependent on f H c using creep compliance function E s b 29200ksi ±0.033±Normal ±±h m ± 1.000.20±Normal±±w =c Variable dependent on f Hc using Bolomey's formula c Others Treated as deterministic design values Modeling errors w c d ± 1.000.23±Normal ±±w s e± 1.000.34±Normal ±±a Design concrete compressive strength at 28days.bGrade 60steel.cw =c 3915= f H c 1957:5 ,f H c is in psi.dModeling error for creep compliance function model.eModeling error for shrinkage strain model.Table 3Summary of construction load statistics Load componentIntensity Arrival Mean COVCDF Average rate Duration Dead load (slab self weight) 1.05D n0.10Normal ±6±24mos.Additional dead load at time of form removal1.05D n ;addl :0.10Normal ±2±3cycles Sustained construction live load 6psf 1.10Gamma 1/Week 1week Stacking load 20psf 0.60Gamma 1Arrival 1month Move-in-load0.19L n a0.66Gamma1Arrival1weekaL n is the nominal service (occupancy)live load.Table 4Summary of service (occupancy)load statistics Load component Intensity ArrivalMean-to-nominal COVCDF Average number (per year)Duration Dead load1.050.10Normal ±50years Sustained live load 0.300.60Gamma 0.1258years Extraordinary live load0.190.66Gamma11week1468 E.H.Khor et al./Computers and Structures 79(2001)1461±1472without construction load for di erent reference periods.For a reference period of one year,the increase in the mean de¯ection over that for the service load only case is about 50%for the 3S case and about 80%for the 2S1R case.However,the early-age e ects become less signi®-cant (evident)for longer reference periods,e.g.,8and 50years,since the creep and shrinkage contributions to de¯ection are more signi®cant over these durations.Fig.10shows the mean maximum time-dependent de¯ections,for total de¯ections and its elastic,creep andshrinkage components (2S1R construction load sce-nario).It is observed that creep and shrinkage account for 60%of long-term (total)de¯ection.This is broadly consistent with ACI provisions in which the additional sustained load de¯ection due to creep and shrinkage is speci®ed as twice the elastic de¯ection.As expected,the COVof the maximum de¯ection increases with time (see Table 5)due to the increased variability associated with a longer load history.The increase with time of the mean maximum de¯ection and variability suggests that the structural member is more likely to experience its life-time maximum de¯ection as the structure ages;see Fig.11for the 2S1R construction load scenario.However,Fig.11also shows that the structure is susceptible to large de¯ection during the construction process.This is a direct consequence of the early-age e ects described previously.Nonetheless,the probability of a maximum de¯ection occurring during construction is still relatively low;for example about 13%and 2%for the 2S1R and 3S construction load scenarios for the case considered here,respectively.A parametric study was performed to assess the ef-fects of di erent beam con®gurations on the long-term de¯parisons were made with respect to the baseline beam and considered the e ects of di erent values of (i)steel ratio q ,(ii)span L ,(iii)humidity h m ,(iv)concrete workmanship [35,37],(v)construction cycle,(vi)construction duration,(vii)design concrete compressive strength f H c and (viii)construction load statistics.The complete results from the parametric studies may be found elsewhere [18].For illustration purposes,selected parametric study results are presented here.Speci®cally,the e ects on long-term de¯ections of varying the steel ratio from q min to q max [4],varying the concrete workmanship,and varying the construction cycle (time per ¯oor)from 3±14days,are presented in Table 5.For the same span and design loads,the beams de-signed using di erent steel ratios have very di erent long-term de¯ections,As expected,the beam design using q max experiences larger de¯ections,while the beam design using q min experiences smaller de¯ections when compared to the baseline beam (designed using 0:5q max ).This is not unexpected as the beam designed using q max results in a smaller e ective depth and hence experiences a larger de¯ection,and vice versa.This increase and decrease in de¯ection is on the order of 50%or more for all reference periods (1,8and 50years).Also as expected,when compared to the baseline beam (having ``fair''workmanship),the beam with the poor concrete workmanship exhibits larger long-term de¯ections while the beam with good concrete work-manship exhibits smaller long-term de¯ections.Poor workmanship results in about a 10%increase in long-term de¯ection while good workmanship results in about a 15%decrease,when compared with thebaselineFig.7.Sample realizations:(a)construction load process for 2S1R construction operation and (b)occupancy (dead plus live)loadprocess.Fig.8.Convergence of statistics on maximum de¯ection (3S scenario,50-year reference period).E.H.Khor et al./Computers and Structures 79(2001)1461±14721469。

英文文章

Journal of Hazardous Materials 177 (2010) 362–371Contents lists available at ScienceDirectJournal of HazardousMaterialsj o u r n a l h o m e p a g e :w w w.e l s e v i e r.c o m /l o c a t e /j h a z m atSorption kinetics and equilibrium for the removal of nickel ions from aqueous phase on calcined Bofe bentonite clayM.G.A.Vieira a ,A.F.Almeida Neto a ,M.L.Gimenes b ,M.G.C.da Silva a ,∗a UNICAMP/FEQ/DTF,Campinas/SP,Brazil bUEM/CTC/DEQ,Maringá/PR,Brazila r t i c l e i n f o Article history:Received 28September 2009Received in revised form 7December 2009Accepted 7December 2009Available online 16 December 2009Keywords:SorptionBentonite clay NickelHeavy metal removala b s t r a c tIn this paper the kinetics and dynamics of nickel adsorption on calcined Bofe bentonite clay were studied.The clay was characterized through EDX,surface area (BET)and XRD analysis.The inﬂuence of param-eters (pH,amount of adsorbent,adsorbate concentration and temperature)was investigated.Kinetic models were evaluated in order to identify potential adsorption process mechanisms.The Langmuir and Freundlich models were utilized for the analysis of adsorption equilibrium.Thermodynamic parameters were assessed as a function of the process temperature.The kinetics data were better represented by the second-order model.The process was found to be strongly inﬂuenced by the factors studied.The Bofe clay removed nickel with maximum adsorption capacity of 1.91mg metal/g of clay (20◦C;pH 5.3)and that the thermodynamic data indicated that the adsorption reaction is spontaneous and of an exothermal nature.The Langmuir model provided the best ﬁt for sorption isotherms.© 2009 Elsevier B.V. All rights reserved.1.IntroductionWater contamination by heavy metals in industrial efﬂuents is a serious environmental problem,leading to the development of studies aimed at their reduction or elimination and waste processing by physical,chemical,thermal,biological or mixed means.Several studies have shown that the selectivity and efﬁciency in the removal of pollutants such as heavy metals from efﬂuents by an adsorption process are strongly dependent upon the physical properties and chemical composition of adsorbents.The literature reports countless studies on heavy metal removal from waters and efﬂuents,including chemical precipitation,phys-ical treatment,such as ion exchange,solvent extraction and adsorption.However,due to the high maintenance and import costs of chemicals or conventional adsorbents,some methods have become unsustainable.Among heavy metals,nickel is one of the most widely used in western society for the manufacture of stainless steel,superalloys,metal alloys,coins,batteries,etc.Direct exposure to nickel causes dermatitis.Some nickel compounds,such as nickel carbonyl,are cancerigenic and easily absorbed by the skin.The exposure to this∗Corresponding author at:State University of Campinas,School of Chemical Engi-neering,Department of Thermoﬂuidynamic Cidade Universitária “Zeferino Vaz”-P.O.Box 6066,13083-970,Campinas –SP,Brazil.Tel.:+551935213928;fax:+551935213922.E-mail address:meuris@feq.unicamp.br (M.G.C.da Silva).compound,at an atmospheric concentration of 30ppm for half an hour,is lethal [1].Clay application for sorption or elimination of heavy metals present in efﬂuents has been focused in a number of studies due to countless economic advantages [2–4].The cost of clays is relatively low as compared to other alternative adsorbents,including acti-vated carbon,natural and synthetic zeolites,ion-exchange resins,and other adsorbent materials.Clays and minerals such as montmo-rillonite,vermiculite,illite,kaolinite and bentonite are among the natural materials that have been investigated as heavy metal adsor-bents [5,6].Another advantage in using clays as adsorbents is their intrinsic properties,such as large speciﬁc surface area,excellent physical and chemical stability,and a number of other structural and surface properties [7].Abollino et al.[8]observed that Na-montmorillonite adsorbs Cd,Cr,Cu,Mn,Ni,Pb or Zn even in the presence of organic substances (ligands).In Covelo et al.[9]Cd,Cr,Cu,Ni,Pb and Zn were adsorbed on mineral clays simultaneously from solutions at different con-centrations.Currently,the smectite clays of bentonite type are among the most investigated clays for heavy metal removal.The smectite clays of Paraíba generally have CEC values between 50and 90meq/100g of clay [10].The bentonite clay can be calcium,sodium or poly-cationic type.The bentonite clays have large surface area (up to 800m 2/g)and form thixotropic gels.Some cations cause such an intense expansion that crystal layers can be broken down to their single cell.The clays that have Na +as the predominant cation,are known to swell in the presence of water,increasing several times its original volume,because the Na +allows many water molecules0304-3894/$–see front matter © 2009 Elsevier B.V. All rights reserved.doi:10.1016/j.jhazmat.2009.12.040M.G.A.Vieira et al./Journal of Hazardous Materials177 (2010) 362–371363Nomenclatureb,q m Langmuir coefﬁcients representing the equilibrium constant for the adsorbate–adsorbent equilibriumand the maximum adsorbed amount on the mono-layerC intraparticle diffusion model constantC eq concentration of metal ions in the liquid phases(mg L−1)C i,C f initial andﬁnal concentration of metal ion in liquidphase,respectively(mg L−1)k1pseudo-ﬁrst-order adsorption rate constantk2second-order adsorption rate constantK d adsorbate distribution coefﬁcient(=q eq/C eq em L/g) K f and n Freundlich coefﬁcientsK i intraparticle diffusion rate constantm mass of adsorbent(g)Q adsorbed mass of metal ion per gram of adsorbent (mg g−1)q eq concentration of metal ions in solid phase at equi-librium(mg g−1)q t adsorbed amount per unit mass at any given time t R universal gas constant(8.314×10−3kJ/(K mol))R L curvature of the sorption isothermT temperature(K)V volume of solution(L)G Gibbs free energy variation(kJ/mol)H enthalpy variation(kJ/mol)S entropy variation(J/(K mol))be adsorbed,increasing the distance between the layers and conse-quently,separating the clay particles from each other.In the case of polycationic or calcium clay,the amount of adsorbed water is lim-ited and the particles remain attached to each other by electrical and mass interactions[11].These characteristics confer bentonite highly speciﬁc properties which have warranted a wide range of applications in severalﬁelds[10].Although the results involving metal removal by clays are signif-icant and promising,these results still need to be better understood regarding the properties of adsorbents for optimizing the condi-tions of the process.The aim of this paper was to study the kinetics and dynamics of nickel adsorption on calcined Bofe bentonite clay inﬁnite bath. The Bofe clay in natura and calcined(before and after subjected to nickel adsorption)was characterized as to its chemical compo-sition through EDX,besides surface area(BET method)and X-ray diffraction analysis.The inﬂuence of several parameters,such as pH, adsorbent amount,adsorbate concentration and temperature were investigated.Kinetic models were tested to identify the poten-tial adsorption process mechanisms.The Langmuir and Freundlich models were utilized for analysis of the adsorption equilibrium. The thermodynamic parameters were assessed as a function of the process temperature.2.Theoretical fundamentalsKinetics for clay–metal interaction was studied thoroughly in this work by applying the following equations and ger-gren equation(Lagergren,1898)[12]expressed by Eq.(1)was appliedﬁrst assuming pseudo-ﬁrst-order kinetics,where the num-ber of metal ions outnumbers the number of adsorption sites on clay surface:ln(q eq−q t)=ln(q eq)−k1·t(1)where q eq and q t are the values for the adsorbed amount per unit mass at equilibrium and at any given time t,and k1is the pseudo-ﬁrst-order adsorption rate constant.The k1values can be obtained from the angular coefﬁcient of the straight line obtained by plotting the ln(q eq−q t)versus t graph.If the validity of theﬁrst-order kinetics is weak,the kinetics can be tested for following second-order mechanism as per the rate law expressed by Eq.(2):tq t=1k2·q eq+1q eq·t(2)where k2·q2eq is described as the initial adsorption rate when t→0. The t/qt versus t graph provides a straight line allowing obtaining q eq and k2.When there is possibility for diffusing the adsorbate species into the adsorbent pores,the intraparticle diffusion rate constant(k i) can be obtained from Eq.(3):q t=k i·t0.5+C(3) In this case,the intraparticle diffusion has a signiﬁcant effect on the control of the adsorption process kinetics.The q t versus t0.5graph provides a straight line passing by the y axis with an inclination equal to the value of k i.The values for C provide an approximation of the boundary layer thickness,the greater the C value,the greater the boundary layer effect is.The deviation of the straight line from the origin may be attributed to a difference in mass transfer between the initial andﬁnal adsorption stages.The adsorption equilibrium is usually described by an isotherm equation whose parameters express the surface properties and afﬁnity of the adsorbent,at a pre-set temperature and pH.The isotherms can be adjusted to mathematical models,especially those of Langmuir[13](Eq.(4))and Freundlich[14](Eq.(5)):q eq=q m·b·C eq1+b·C eq(4)where C eq(mg L−1)and q eq(mg g−1)are,respectively,the concen-tration of metal ions in the liquid and solid phases;b and q m are Langmuir coefﬁcients representing the equilibrium constant for the adsorbate–adsorbent equilibrium and the maximum adsorbed amount on the monolayer.q eq=(K f·C eq)n(5) where K f and n are Freundlich coefﬁcients.The essential characteristics of the Langmuir isotherm can be expressed by a dimensionless number constant,the separation fac-tor or equilibrium parameter(R L)given by Eq.(6):R L=11+b·C0(6)where C0(mg L−1)is the initial concentration of the metal in the liquid phase.The parameter R L indicates the curvature of the sorption isotherm:if R L>1,the isotherm is not favorable;if R L=1,linear; 0<R L<1,favorable;R L=0,irreversible.The thermodynamic parameters for the adsorption process H (kJ/mol), S(J/(K mol))and G(kJ/mol)were evaluated using ther-modynamic equations(7)and(8):G=−RT.ln(K d)(7)ln(K d)=−GRT= SR− HRT(8)where K d is the adsorbate distribution coefﬁcient(=q eq/C eq em L/g);T the temperature(K);R the universal gas constant (8.314×10−3kJ/(K mol)).364M.G.A.Vieira et al./Journal of Hazardous Materials177 (2010) 362–371The ln(K d)versus1/T graph must be linear with inclination of the straight line(− H/R)and intercept the y axis at( S/R),providing the values for H and S.The variation in Gibbs free energy( G) is the fundamental criterion of process spontaneity.3.Materials and methods3.1.Clay adsorbentIn this paper,a Bofe-type bentonite clay from Boa Vista,Paraíba, located in the northeastern region of Brazil,was used as adsorbent. The clay was prepared by size classiﬁcation,calcined at500◦C for 24h in order to increase its mechanical resistance and to eliminate some impurities.3.2.Clay characterizationThe physical–chemical characterization of Bofe clay was per-formed by energy-dispersive X-ray spectroscopy(EDX)(Oxford, model7060).This analysis allows the overall chemical composition of a solid to be identiﬁed and qualiﬁed.The surface area and volume of pores and micropores were obtained by N2physisorption(BET method)at77K.These anal-yses were performed in a Micromeritics Gemini III2375Surface Area Analyzer device using the BET method.The identiﬁcation of particular clay peaks and maintenance of its properties were obtained by X-ray diffraction(Philips,model X’PERT)(Copper K␣radiation;voltage:40kV;current:40mA;step size:0.0202Â;time per step:1.000s;angle of incidence:3–50◦).The analyses mentioned were carried out for natural and cal-cined Bofe clay samples before and after nickel adsorption.3.3.Bath sorption procedureThe adsorption experiments were carried out using an aqueous solution with Ni(NO3)2·6H2O at theﬁxed concentrations inﬁnite bath at controlled temperature under constant stirring at150rpm. At speciﬁc time intervals,solution aliquots were removed and cen-trifuged.The supernatant liquid was diluted and its concentration was determined by atomic absorption spectrometry(Perkin Elmer AA Analyst100with air-acetylene oxidizingﬂame).In this part of the work,the experiments were conducted inﬁve groups to see the effect of adsorbent amount,adsorbate concentra-tion,pH of the adsorbate solution,contact time and temperature. The experimental procedure mentioned above was used in each group by making some minor changes depending on the parameter studied.During the determination of effect of contact time,the experi-ments were conducted by using1g of clay per100mL of solution at 50mg/L concentration.Temperature and pH were kept as constant at293K and5.3,respectively.The samples were shaken for a time interval between0and250min.The effect of pH was studied by changing the pH between2.0 and10.0and by keeping the amount of clay,solution concentration and temperature same as with the kinetics part.The experiments were repeated with different clay amounts, adsorbate concentration,pH of the adsorbate solution,interaction time and temperature.For maintaining pH of the medium,either 0.01N HNO3or0.01N NH4(OH)was added in order to set a speciﬁc pH value and the pH was monitored both before and after adsorp-tion.The following conditions were maintained for the different sets of experiments:(i)Kinetics:clay1g/100mL,Ni(II)50mg/L,temperature293K,pH5.3,interaction time250min.Classical models(Eqs.(1)–(3))wereﬁtted.Table1Percentage of compounds in Bofe clay.Element Molecular(%)Bofe clay in natura Bofe clay calcined Bofe claycalcined+NiNa0.540.50–Mg 1.34 1.19 1.12Al7.43 6.84 6.75Si46.646.1737.32K0.12a––Ca0.440.580.29Ti0.420.530.43Fe 3.58 3.32 3.83Ni––0.72Total60.8559.1349.46a≤2␴.(ii)Effects of pH:clay1g/100mL,Ni(II)50mg/L(0.85mM),tem-perature293K,interaction time150min,pH2.0–10.0at unit. (iii)Effects of adsorbent amount:Ni(II)50mg/L,temperature293K, pH5.3,interaction time150min,clay0.5g,1g,2g,3g and4g of clay/100mL.(iv)Effects of adsorbate concentration and adsorption isotherm: clay1g/100mL.Langmuir’s theoretical model and Freundlich’s empirical model were adjusted to the adsorption isotherms.The adsorbed amount was obtained by Eq.(9):Q=V(C i−C f)m(9)where Q the adsorbed mass of metal ion per gram of adsorbent (mg g−1);V the volume of solution(L);C i,C f the initial andﬁnal concentration of metal ion,respectively(mg L−1);m the mass of adsorbent(g).(v)Thermodynamics:clay1g/100mL,time150min,pH5.3,tem-perature293,313,323and348K,Ni(II)concentrations at linear region of isotherm curves where Henry’s law for inﬁnite dilu-tion is valid.4.Results and discussion4.1.Adsorbent characterization4.1.1.Chemical composition by EDXThe molecular composition of the compounds in natura,calcined and calcined with adsorbed nickel Bofe clays is shown in Table1. All ions shown in the average composition,except for nickel,have a percentage within the expected for this clay,according to data from Souza Santos[10].EDX is only a qualitative analysis and was used for understanding the chemical composition of Bofe clay and the corresponding values of percentage of compounds obtained, although an average of three measures should not be quantiﬁed. The presence of nickel after adsorption shows that indeed this metal was adsorbed by clay and now appears as part of its chemical composition.According to the chemical composition analysis,the clay used in this work is a polycationic bentonite due to the presence of Ca2+, Mg2+and Na+cations in natural and calcined clay samples.This type of clay is the most often found one in Brazil[15].The quantitative C.E.C.values obtained for Bofe clay“in natura”and calcined are,respectively,93.333±5.739and55.652±4.260. The smectite clays of Paraíba generally have CEC values between50 and90meq/100g of clay[10].The comparatively high CEC value of the“in natura”clay indicates that the minerals have a high level of isomorphic substitutions.Moreover the smectite calcined at500◦C has the ability to exchange cations drastically reduced in relation to the natural clay.M.G.A.Vieira et al./Journal of Hazardous Materials177 (2010) 362–371365Fig.1.(a)Adsorption isotherms and N2desorption at77K.Theﬁlled dots represent adsorption and the blank ones,desorption.(b)Increase in intrusion(cm3/g)versus pore diameter(nm)on Bofe clay.The compound percentages obtained by EDX show that there was virtually no change to the chemical composition of the clay after its calcination,the main elements being preserved,such as silicon and aluminum,as well as to exchangeable cations.With nickel adsorption,there was a reduction in the amount of Ca2+and Mg2+cations and disappearance of Na+cations.That indicates that ion exchange occurred in the process,especially with Na+,which is more easily exchangeable because it is monovalent.After nickel adsorption,a small percentage of this ion is found in the clay com-position.Furthermore,from the metal speciation and the pH study per-formed,the pH of adsorbate solution can be kept below 5.8. Moreover,it has been veriﬁed that above pH5.0the natural and cal-cined clays have surface charges very close to neutrality.Thus,with the solid lightly charged(neutral),forces of attraction between the adsorbent and the adsorbate must be of the magnitude of adsorp-tion and/or ion exchange.Therefore,both phenomena(adsorption and ion exchange)probably occur during nickel removal.4.1.2.N2physisorption(BET)The values obtained for the surface area by the BET method for in natura,calcined and calcined with adsorbed nickel Bofe clay sam-ples are found in Table2.The correspondent N2adsorption and desorption isotherms and pore diameter as a function of intru-sion increase are shown in Fig.1.This method was chosen because it presents the bestﬁts of data,when compared to those of the Langmuir model,in addition to the similar behavior of the curves obtained with BET isotherms.Using BET adsorption isotherms,the volume of micropores(V mi) and mesopores(V mes)is obtained by reading the adsorbed volume (V ads)at P/P P0=0.10and0.95,expressed by Eqs.(10)and(11)[16]: V mi=V ads(P/P=0.10)(10)V mes=V ads(P/P=0.95)−V ads(P/P0=0.10)(11) An increase in the surface area(12.8%),as well as in the volume of clay micropores(9.8%)and mesopores(30.1%),is observed after calcination,due to loss by dehydration and dehydroxylation.It is possible that calcination increased the microporosity of the clay and expanded the micropores upon releasing binding water,forming pores in the size range of mesopores.Table2Sample surface area by BET method.Bofe clay Surface area(m2/g)R2V mi(cm3/g)V mes(cm3/g)In natura78.89090.999619.72524.560 Calcined89.01910.999721.66031.945 Calcined+Ni92.58970.999723.35631.755With nickel adsorption on the clay,there was a slight increase in the surface area of the clay,with development of microporos-ity(increase by7.8%),while the volume of mesopores was slightly reduced(0.6%).The replacement of Na+cations with Ni2+cations led to an increase in the lamellar interplanar distance of the clay, which may account for the increase in the surface area of the clay following the nickel adsorption process.In analyzing the behavior of the isotherms obtained,we can clas-sify them according to Brunauer,Emmet and Teller[17]as type II or BET isotherms,characterized by the formation of adsorbed molecule multilayers on the surface of a solid.This type of sig-moidal(S-shaped)isotherm is often found in solids having pores larger than micropores(mesopores).The Bofe clay presented sur-face areas that were very favorable for all analyzed samples.In Fig.1a,it is observed that the position of the N2desorp-tion isotherm virtually coincides with that of adsorption,that is, the hysteresis phenomenon characterizing the irreversibility of the sorption process can be neglected for all analyzed samples.This indicates that nickel adsorption into and desorption from Bofe clay pores is virtually reversible[18].Fig.1b shows bands of pore diameter predominant in Bofe clay, which according to the pore diameter classiﬁcation of IUPAC[18], the pores can be designated as macropores(pores with width larger than50nm),mesopores(pores with width between2and50nm) and micropores(pores with diameter below2nm).Thisﬁgure, together with Table2,which are presented the volumes of micro and mesopores,indicate the alterations in size of diameter of pores occurring in the clay after calcination and adsorption of nickel.The presence of micropores and mesopores is observed in all Bofe clay samples,with predominance of mesoporosity.4.1.3.X-ray diffractionThe XRD analysis for clay samples of Bofe in natura,before adsorption,calcination and submission to nickel adsorption is shown in Fig.2.In each diffractogram,for the considered band, there are two characteristic peaks for montmorillonite and the others are related to quartz.To easily identify them,the peaks refer-ring to montmorillonite are marked with letter‘M’and the others related to quartz with letter‘Q’.Considering the angles that correspond to the montmorillonite peaks and applying Bragg’s law(n =2d sinÂ),for the of1.542Åvalue,d is obtained,which represents the basal interlayer distances of Bofe clay,whose results are shown in Table3.It can be observed that the Bofe clay samples analysed are not characterized by a highly crystalline structure,as it is found,for example,in zeolites,since the peaks detected in these samples are well deﬁned.The difﬁculty in identifying peaks is explained by non-diffraction of X-ray,which had a deviation throughout the process,366M.G.A.Vieira et al./Journal of Hazardous Materials177 (2010) 362–371Fig.2.Diffractogram of Bofe in natura,calcined at500◦C and calcined+Ni adsorbed clays.what could characterize the formation of an inter-crystalline joint of clays.Through the diffractograms,there is a signiﬁcant deviation of the particular montmorillonite peak(Bofe in natura)(2Â=5.66◦) for an angle2Âhigher(8.76◦<2Â<8.80◦)obtained for the other samples,which indicates shorter plane interlayer distances(d001).In Table3,all samples in the angles of incidence(2Â)between 19.6◦and19.9◦regarding the second montmorillonite peak, showed practically the same interlayer basal distances(around 4.5Å).In the angles of incidence(2Â)between5.66◦and8.88◦, regarding theﬁrst montmorillonite peak,the Bofe clay in natura sample showed a longer interlayer spacing(d001=15.6Å)than that of the calcined clay samples(with or without adsorbed Ni),whose values ranged around10Å.4.2.Nickel speciation and pH ZPCFig.3shows the speciation curve of the Ni2+ion in aqueous solution with nitrate ions at a concentration of0.85mM(50ppm) determined through the HYDRA application.In the pH range of 6.5–8,the fraction of Ni2+ions in aqueous solution decreases and the formation of nickel hydroxide begins,which is precipitated.To ensure that only the adsorption process will occur,one must use a pH value below that of minimum precipitation,which corresponds to6.5for this concentration(50ppm)and ionic strength.In addition to the nickel speciation curve obtained by the HYDRA application,another important property to be considered is the pH ZPC,which corresponds to the value at which the surface charges of a suspended solid is zero.The pH ZPC of the natural and calcined Bofe clays(see Fig.4)was obtained according to the potentiometric titration methodology described by Davranche[19].Table3Identiﬁcation of montimorillonite peaks and interlayer distance found by Bragg’s method.Bofe clayCorresponding angle(2Â—grades)Basal interlayer distance(Å)In natura 5.6615.6119.8 4.48 Calcined8.8010.0519.8 4.48 Calcined+Ni8.7610.0919.6 4.53Fig.3.Ni(II)speciation curve at a concentration of50ppm(0.85mM).According to Fig.4,the pH ZPC values obtained for the natural and calcined Bofe clays are,respectively,6.1and5.3.Thus,in order to ensure that the clay surface has a null or negative charge so as to make the adsorption of positively charged metal ions more favorable,the adsorbate solution pH must be kept below5.3.The pH of the dispersions formed by the clays Bofe in natura and calcined was measured directly,where1g of the clay was dispersed in100mL of deionized water.The results of this study were7.78±0.01and4.27±0.01for in natura and calcined clay, respectively.The pH of a clay results in part from the nature of exchangeable ions.According to the chemical composition,the exchangeable ions of the in natura Bofe clay are cations of alkali metals and alkaline earth metals,which give an alkaline pH to dis-persions formed by natural clays.With the calcination,there is no loss of cations,but it occurs the dehydroxylation,which gives an acid pH to the dispersion formed with this state of the Bofe clay.4.3.Adsorption kineticsFig.5a and b presents the curve for nickel adsorption kinetics at an initial concentration of41.5ppm on calcined Bofe bentonite clay at500◦C(24h).The adsorption of nickel ions into clay pores is found to occur rapidly at theﬁrst moments of the process, remaining virtually at equilibrium over time.The reduction in the concentration of this ion under the condition of this study was40%, compared to the initial concentration of50ppm.The maximumadsorbed amount was1.91mg of metal/g of clay.The adsorption kinetics was adjusted with the pseudo-ﬁrst-order(Fig.5c),the second-order kinetics model(Fig.5d)and Fig.4.pH ZPC of Bofe clay in natura and calcined.M.G.A.Vieira et al./Journal of Hazardous Materials177 (2010) 362–371367Fig.5.Kinetic curve for nickel adsorption on calcined Bofe clay.(a)Adsorbed amount at equilibrium;(b)dimensionless solution concentration as a function of adsorption time.Fit of(c)pseudo-ﬁrst-order kinetic model;(d)second-order kinetic model;(e)intraparticle kinetic model to Ni(II)adsorption on calcined Bofe clay(1g clay/100mL solution).the intraparticle diffusion model(Fig.5e).The linear correlation coefﬁcients and pseudo-ﬁrst-order constants(k1),second-order constants(k2)and intraparticle diffusion constants(k i),as well as the equilibrium capacity obtained in Fig.5are shown in Table4.Actually the existence of two slopes in Fig.5c indicates two different lines and also second-order mechanism.Moreover the intraparticle diffusion model was less suitable for experimental data if compared with the second-order kinetic model,indicating that the diffusion of metal species into pores is the prevailing fac-tor controlling the process mechanism.The second-order kinetics model showed excellent linearity(R2=0.99)and tends to repre-sent more satisfactorily the mechanism of the interactions involved during nickel adsorption into the calcined Bofe clay pores.The val-ues of the experimental q eq,calculated by the second-order model, showed greater agreement,with deviation of5.7%.4.4.Effect of pHAccording to Peltier and Sparks[20],the inﬂuence of pH on the characteristics of Ni(II)ion sorption on clay must be carefully exam-ined and controlled.Fig.6and Table5show the effect of pH on the process.Table4Ni(II)adsorption rate coefﬁcients for pseudo-ﬁrst-order and second-order models and intraparticle diffusion on calcined Bofe clay. Pseudo-ﬁrst-order(Eq.(1))Second-order(Eq.(2))Intraparticle diffusion(Eq.(3))k1=0.0069g/(mg min)k2=0.2113g/(mg min)k i=0.0245mg/(g min)q eq=0.35mg min/g q eq=1.80mg min/g C=1.4092R2=0.9009R2=0.9971R2=0.9557。

MIT18_05S14_Reading6a

b
E (X ) =
a
xf (x) dx.
Let’s see how this compares with the formula for a discrete random variable:
n
E (X ) =
i=1
xi p(xi ).
The discrete formula says to take a weighted sum of the values xi of X , where the weights are the probabilities p(xi ). Recall that f (x) is a probability density. Its units are prob/(unit of X ). 1
3
1 2 answer: The range of Z is (−∞, ∞) and its pdf is φ(z ) = √ e−z /2 . So (details in 2π appendix) ∞ ∞ 1 1 2 2 √ z e−z /2 dz = − √ e−z /2 = 0. E (Z ) = 2π 2π −∞ −∞
1
E (X ) =
0
x dx =
x2 2
1
=
0
1 . 2
Not surprisingly the mean is at the midpoint of the range.
2 Example 2. Let X have range [0, 2] and density 3 8 x . Find E (X ).
Expectation, Variance and Standard Deviation for Continuous Random Variables Class 6, 18.05 Jeremy Orloﬀ and Jonathan Bloom 1 Learning Goals

OliverTwist

Charles Dickens and His Work Oliver Twist姓名：***专业：英语学号：**********Charles Dickens and His Work Oliver Twist IntroductionMy essay is mainly about the evaluation of Charles Dickens and the appreciation of one of his famous work Oliver Twist. Respectively from writing purpose, writing style, language features and characters to analyze the work.The introduction of Charles DickensCharles Dickens (1812~1870) is a famous novelist in England in the 19th century. He is known as the most representative novelist, and he achieves the highest degree in literature, thus he influences the world a lot. In his youth, he suffered ups and downs, which was the foundation of his novels. He is honored as “Novelist of Shakespeare”and “British Balzac”. His works reflect the bitter satire and heartless criticism, and he reveals the cruel exploitation of the capitalists to workers and laborer, criticizes the social various unreasonable phenomena, and shows the sympathy to the oppressed people.Charles Dickens has written a lot of novels, and the work Oliver Twist impresses me a lot. Here I will talk something about Oliver Twist. The writing purpose of Oliver TwistOliver Twist is used to call the public’s attention to various contemporary social evils, including the workhouse, child labor and the recruitment of children as criminals, the novel is full of sarcasm and darkhumor, revealing the hypocrisies of the time.Charles Dickens frequently uses houses to symbolize the people who inhabit them. He uses vivid description, similes, metaphors, personification, and imagery to describe the essence of the cha racter’s personality and traits, and he is good at employing caricatures to reveal the ugly social truths. In Oliver Twist,Dickens provides readers with an idealized figure of a young boy so inherently and unrealistically “good” that his values are never subverted by either cruel orphanages or a gang of young pick pockets. This idealism is aimed to high light Dickens’s goal of poignant social commentary.In Oliver Twist, the specific characteristic of language is a measure that Dickens used to portray characters. Rogues, thieves, robbers and prostitutes’ l anguage in the book are fit in with their identity and status. He even used bandits’ words; however, he processed, refined, chose them, and avoided using the filthy and obscene words. Oliver’s language was standard, his attitude and choice of word during a talk was elegant. But he was an orphan grown up in the hospices, and he never gained any good education and whom he interacted with were the people full of evil and degenerate. Why could he speak so well English? On the point of myview, Dickens put his own idea into the novel, rather than pursuing the completely lifelike true.The analysis of three major charactersOliver Twist: The main character of the story, he is little boy who is eager for concern and love. He was abused as a helpless child, but he is still filled with hope of the world.Fagin: The main antagonist in the story, he is a powerful crime leader who draws water to his mill and heartless and cruel.Nancy: A woman who works for Fagin and tries to help Oliver which eventually leads to her death. She is passionate, caring, and loves Sikes, who eventually kills her.ConclusionAccording to my understanding of Charles Dickens, he is a great man and he puts the English novel creation to the unprecedented heights, and his novels represented the highest achievement of critical realism novels. He used his unique writing style, such as satire, humor, hyperbole, and caricature, to shape a series of vivid and unforgettable image, which fully demonstrated the Victorian life pictures.。

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In much of Australia, Aldi filled a void in the discount supermarket business that arose when the discount grocery chainFranklins, in 2002, became limited to New South Wales. Although Aldi had been operating in a few locations in Australia since the late 1990s, other discount supermarkets, sr purchased or pushed out of the Supermarket business by Coles and Woolworths at about the same time. On 17 December 2008, Aldi opened its 200th Australian store; its supermarkets are in Victoria, New South Wales, the Australian Capital Territory, and Queensland.
In the USA, as with most American supermarkets, Aldi acceptspublic assistance debit-style cardsas payment.
Distribution of Aldi within Germany (the so-calledAldi-equator)
The earliest roots of the company trace back to 1913, when the mother ofKarlandTheo Albrechtopened a small store in a suburb ofEssen. Their father was employed as aminerand later as abaker’s assistant. Karl Albrecht was born in 1920, Theo Albrecht in 1922. Theo Albrecht completed anapprenticeshipin his mother’s store, while Karl Albrecht worked in adelicatessen. Karl Albrecht took over a food shop formerly run by F. W. Judt who already advertised that they were the "cheapest food source". Karl Albrecht served in theGerman ArmyduringWorld War II. In 1946, the brothers took over their mother’s business and soon opened another retail outlet nearby. By 1950, the Albrecht brothers owned 13 stores in theRuhr Valley.[citation needed]
Internationally
The ALDI group operates over 8,000 stores worldwide. A store opens roughly every week in Britain alone.[8]
ALDI Nord is responsible for its stores inBelgium, theNetherlands,Luxembourg,France,Poland,Spain,Denmark, andPortugal, and also operates theTrader Joe'ssupermarket chain in the United States. Aldi Süd's responsibilities are in theUSA(operating undertheAldiname),AustriaandSlovenia(asHofer),Great Britain,Ireland,Australia, andSwitzerland. Aldi Süd's firstSwitzerlandstore opened in 2005, while it has operated inHungarysince 2007. Aldi Süd had invested an estimated €800m ($1bn; £670m) in Greece from November 2008 until pulling out on 31 December 2010.[9]
In Great Britain, Aldi opened its 500th store in October 2013 and now has a market share of 3.6%.[11]Aldi has opened stores in affluent locations includingKnutsfordandBury St EdmundsAldi has been aggressively recruiting management staff at top UK universities.[12]
Whilst ALDI Nord has renamed its Dutch and Belgian subsidiariesCombiandLansato theAldi Markt/Aldi Marchébrand, Aldi Süd tries to maintain a regional appearance, branding its storesAldi Südin Germany,Aldi Suissein Switzerland, andHoferin Austria and Slovenia.[10]
When the brothers split the company in 1960 over a dispute whether they should sell cigarettes at thetill, they owned 300 shops with a cash flow ofDM90 million yearly. In 1962, they introduced the nameAldi—short forAlbrecht-Diskont. Aldi Nord and Aldi Süd have been financially and legally separate since 1966, although both divisions' names may appear (as if they were a single enterprise) with certainhouse brandsor when negotiating withcontractorcompanies.
The brothers' idea, which was new at the time, was to subtract the legal maximum rebate of 3% before sale. The market leaders at the time, which often wereco-operatives, required their customers to collect rebate stamps, and to send them at regular intervals to reclaim their money. The Albrecht brothers also rigorously removed merchandise that did not sell from their shelves, cutting costs by neither advertising nor selling fresh produce, and keeping the size of their retail outlets small.[citation needed]
Germany
The Aldi Nord group currently consists of 35 independent regional branches with approximately 2,500 stores. Aldi Süd is made up of 31 companies with 1,600 stores. The border between their territories runs from theRhineviaMülheim an der Ruhr,Wermelskirchen,Marburg,Siegen, andGießeneast to just north ofFulda. The formerEast Germanyis served by Aldi Nord, except for one Aldi Süd inSonneberg,Thuringia, whose regional office is inBavaria. The regional branches are organised aslimited partnershipswith a regional manager for each branch who reports directly to the head office inEssen(Aldi Nord) orMülheim an der Ruhr(Aldi Süd).