Critical nature of the giant field-induced pyroelectric response in Pb(Mg13Nb23)O3–xPbTiO3 single c

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英语作文伟大的科学家

Great scientists have always been the cornerstone of human progress,contributing significantly to the advancement of knowledge,technology,and societal development. Here are some key points to consider when writing an essay about a great scientist:1.Introduction to the Scientist:Begin by introducing the scientist,mentioning their full name,field of expertise,and the era in which they lived.For example,Albert Einstein was a theoretical physicist who developed the theory of relativity in the early20th century.2.Early Life and Education:Describe the early life and educational background of the scientist.This can include their upbringing,any significant influences,and their journey through formal education.For instance,Isaac Newton was born in Woolsthorpe,England, and his early interest in mathematics and natural philosophy was fostered by his education at the University of Cambridge.3.Major Contributions:Highlight the scientists most significant contributions to their field.This could be a groundbreaking theory,invention,or discovery.For example, Marie Curies research on radioactivity led to the discovery of the elements polonium and radium.4.Impact on Society and Science:Discuss the impact of the scientists work on society and the scientific community.This can include how their discoveries have been applied, the awards they received,and their influence on future generations of scientists.For example,Charles Darwins theory of evolution by natural selection has had profound implications for biology and our understanding of the natural world.5.Personal Life and Challenges:Its also important to touch upon the personal life of the scientist,including any challenges they faced,both professionally and personally.This can humanize the figure and provide context for their work.For example,Albert Einstein faced political persecution and had to flee Nazi Germany.6.Legacy and Current Relevance:Conclude by discussing the lasting legacy of the scientist and the relevance of their work in todays world.This could include ongoing research inspired by their work or how their ideas have been integrated into modern technology and society.For instance,the principles of quantum mechanics,pioneered by scientists like Max Planck and Niels Bohr,are fundamental to the development of modern electronics.7.Citation and References:Ensure that you cite and reference the sources of information you use in your essay.This not only gives credit to the original authors but also addscredibility to your work.nguage and Style:Use clear and concise language,avoiding overly technical jargon unless it is necessary for the context.The essay should be wellstructured,with a logical flow of ideas,and should engage the readers interest.9.Critical Analysis:While its important to praise the achievements of the scientist,its also valuable to provide a balanced view by discussing any controversies or criticisms associated with their work.10.Conclusion:Summarize the main points of your essay,reiterating the significance of the scientists contributions and their enduring influence on the field of science and society.By following these guidelines,you can craft a comprehensive and engaging essay about a great scientist,offering insights into their life,work,and the lasting impact of their discoveries.。

the rice fleld of the tiny village of阅读题

the rice fleld of the tiny village of阅读题The Rice Field of the Tiny VillageIn a small, remote village nestled between rolling hills and lush green pastures, there was a humble rice field that flourished under the careful cultivation of the villagers. The harvest from this field was the lifeblood of the community, providing sustenance and income for all its inhabitants.Every morning, as the golden rays of the sun began to peek over the horizon, the villagers would gather in the field. Clad in their traditional attire, they worked tirelessly, knee-deep in muddy water, carefully tending to every rice plant. The rhythm of their laborious tasks was harmonized by their synchronized movements, reflecting the unity and collaboration they shared.Throughout the year, the villagers followed a meticulous schedule that revolved around the progress of the rice field. Once the crop had been planted, they diligently monitored its growth, ensuring that each plant received enough nutrients and water to thrive. They worked in harmony with nature, allowing the rain to nourish the field when it fell, and meticulously diverting water from the nearby stream to irrigate the crops during dry spells.During the hot summer months, the villagers would gather in the field, their laughter and chatter echoing through the air, as they harvested the ripe rice. Their hands moved with precision, cutting down the stalks one by one, and gently cradling the heavy ears of rice in woven baskets. The field bustled with activity, as villagers young and old joined forces to preserve their rich agriculturaltradition.Once the harvest was complete, the villagers would celebrate with a traditional festival. The rice field was transformed into a lively gathering place, adorned with vibrant decorations and filled with the aroma of delicious dishes made from their freshly harvested rice. The villagers danced, sang songs of gratitude, and shared stories late into the night, rejoicing in the abundance that the rice field had provided.Beyond its practical significance, the rice field held a deeper meaning for the villagers. It symbolized their connection to the land, their gratitude for nature's gifts, and their reliance on each other. The rice field taught them patience, resilience, and the importance of working together towards a common goal.As time went on and the world around them changed, the small village and its rice field remained a steadfast haven of tradition and tranquility. The villagers continued to uphold the sacred bond with the land, passing down their knowledge and skills from one generation to the next.Today, the rice field of the tiny village stands as a testament to the perseverance of its people, the beauty of their culture, and the timeless cycle of life that unfolds within its boundaries. It serves as a reminder that even in the smallest of places, great abundance can be found, and profound lessons can be learned.。

历年专四完形填空及答案

2000年一．The difference between a liquid and a gas is obvious (26) the conditions of temperature and pressure commonly found at the surface of the Earth. A liquid can be kept in an open container and (27) it to the level of a free surface. A gas forms no free surface but (28) to diffuse throughout the space available; it must (29) be kept in a closed container, as (30) a planet's atmosphere. The distinction was a prominent feature of early theories (31) the phases of matter. In the nineteenth century, for example, one theory maintained that a liquid could be "dissolved" in a vapor without losing its identity, and another theory held that the two phases are( 32 )different kinds o f molecules(分子). The theories now prevailing (33) a quit e different approach by emphasizing what liquids and gases have in common. They are both forms of matter that have no permanent structure and they both flow ea silly. They are fluids.The( 34 )similarly of liquids and gases becomes clearly apparent when the temperature and pressure are raised somewhat.(35) A closed container partially filled with a liquid is heated. The liquid expands or (36) becomes less dense; some of it evaporates. (37), the vapor above the liquid surface becomes dense r as the evaporated molecules are added to it. The combination of temperature and d pressure (38) the densities become equal is (39) the critical point. Above the critical point the liquid and the gas can no longer be( 40 ); there is a single, undifferentiated fluid phase of uniform density.26. A. in B. on C. under D. beyond27. A. fills B. be filled C. filling D. to fill28. A. intends B. tends C. inclines D. contends29. A. however B. nevertheless C. so D. therefore30.A. in the event of B. in the case of C. with a view to D. with reference to31. A. having described B. described C. describing D. to have described32. A. made up of B. consisted of C. constituted of D. made from33. A. apply B. adapt C. take D. conduct34. A. elementary B. crucial C. rudimentary D. fundamental35. A. Suppose B. To suppose C. Being supposed D. Supposed36. A. in a word B. in the meantime C. in other words D. in that case37. A. Similarly B. In contrast C. Furthermore D. Instead38. A. on that B. on which C. at that D. at which39. A. known B. defined C. called D. referred to40. A. classified B. recognized C. categorized D. distinguished2001The translator must have an excellent, up-to-date knowledge of his source languages, full facility in the handling of his target language, which will be his mother tongue or language of habitual ( 26 )and a knowledge and understanding of the latest subject-matter in his field of specialization.This is, as it were, his professional equipment.( 27 )this, it is desirable that he should have an inquiring mind, wide interests, a good memory and the ability to grasp quickly the basic principles of new developments. He should be willing to work ( 28 )is own, often at high speeds, but should be humble enough to consult others ( 29 )his own knowledge not always prove adequate to the task in hand. He should be able to type fairly quickly and accurately and, if he is working mainly for publication, should have more than a nodding ( 30 )with printing techniques and proof-reading. If he is working basically as an information translator, let us say, for an industrial firm, he should have the flexibility of mind to enable him to ( 31 )rapidly from one source language to another, as well as from one subject-matter to another, since this ability is frequently ( 32 )of him in such work. Bearing in mind the nature of the translator’s worksite. The processing of the written word, it is, strictly speaking, ( 33 )that he should be able to speak the language he is dealing with. If he does speak them, it is an advantage (34) a hindrance, but this skill is in many ways a luxury that he can (35) with. It is, (36), desirable that he should have an approximate idea about the pronunciation of his source languages even if this is restricted to ( 37 )how proper names and place names are pronounced. The same ( 38 )to an ability to write his source languages. If he can, well and good; if he cannot, it does not ( 39 ). There are many other skills and ( 40 )that are desirable in a translator.26. A. application B. use C. utility D. usage27. A. More than B Except fo C.Because of D.In addition to28. A. of B. by C. for D. on29. A. should B. when C. because D. if30. A. familiariy B. acquaintance C. knowledge D. skill31. A. change B. transform C. turn D. switch32. A. lacked B. required C. faced D. confronted33. A. essential B. unnecessary C. advantageous D. useless34. A. over B. despite C. rather than D. instead35. A. deal B. concern C. work D. do away36. A. however B. accordingly C. consequently D. thus37. A. knowing B. having known C. know D. have known38. A. refers B. comes C. applies D. amounts39. A. matter B. mind C. harm D. work40. A. characteristics B. qualities C. distinctions D. features 2002年People thinking about the origin of language for the first time usually arrive at the conclusion that it developed gradually as a system of grunts, hisses and cries and ( 26 ) a very simple affair in the beginning.( 27 ), when we observe the language behaviour of ( 28 )we regard as primitive cultures,we find it ( 29 )complicated. It was believed that an Eskimo musthave the tip of his tongue a vocabulary of more than 10,000 words ( 30 ) to get along reasonably well, much larger than the active vocabulary of an average businessman who speaks English.( 31 ), these Eskimo words are far more highly infleeted(词尾变化的) than ( 32 ) of any of the well -known European languages,for a( 33 )noun can be spoken or written in ( 34 ) hundred different forms, each ( 35 )a precise meaning different from that of any other.The forms of the verbs are even more( 36 ). The Eskimo language is, therefore,one of the most difficult in the world to learn,( 37 ) the result that almost no traders or explorers have( 38 )tried to learn it. Consequently , there has grown up, in communication between Eskimos and whites, a jargon ( 39 )to the pidgin English used in Old China, with a vocabulary of from 300 to 600 uninflected words. Most of them are derived from Eskimo but some are derived from English, Danish,Spanish, Hawaiian and other languages. It is this jargon that is usually( 40 ) by travellers as “the Eskimo language”.26. A. must be B. must have been C. ought to be D. should be27. A. However B. Therefore C. Probably D. Undoubtedly28. A. whose B. that C.which D.what29. A. conspicuously B. usually C. surprisingly D. sufficiently30. A. so as B. so that C. as such D. as well as31. A. However B. Moreover C. Though D. Therefore32. A. the others B. all others C. these D. those33. A. single B. singular C. plural D. compound34. A. some B. several C. various D. varied35. A. getting B. causing C. having D. owning36. A. endless B. multiple C. uncountable D. numerous37. A. with B. for C. owing to D.as38. A. still B. indeed C. just D. even39. A. alike B. similar C. related D. relevant40. A. referred to B. talked about C. spoken D. told 2003年During McDonald’s early years French fries were made from scratch every day. Russet Burbank potatoes were (26), cut into shoestrings, and fried in its kitchens. (27)the chain expanded nationwide, in the mid-1960s, it sought to cut labour costs, reduce the number of suppliers, and (28) that its fries tasted the same at every resta urant. McDonald’s began (29) to frozen French fries in 1966—and few customers noticed the difference. (30), the change had a profound effect on the nation’s agriculture and diet. A familiar food had been transformed into a highly processed industrial (31). McDonald’s fries now come from huge manufacturing plants (32) can process two million pounds of potatoes a day. The expansion (33) McDonald’s and the popularity of itslow-cost, mass-produced fries changed the way Americans eat.The taste of McDonald’s French fries played a crucial role in the chain’s success—fries are much more profitable than hamburgers—and was (34) praised by customers, competitors, and even food critics. Their (35) taste does not stem from the kind of p otatoes that McDonald’s (36), the technology that processes them, or the restaurant equipment that fries them: other chains use Russet Burbank, buy their French fries from the (37) large processing companies, and have similar (38) in their restaurant kitchens. The taste of a French fry is (39)determined by the cooking oil. For decades McDonald’s cooked its French fries in a mixture of about 7 per cent cottonseed oil and 93per cent beef fat. The mixture gave the fries their unique (40).26. A.scaled B.stripped C.peeled D.sliced27. A.As B.Due to C.Owing to D.With28. A.ensue B.ensure C.enrich D.enable29. A.switching B.diverting C.modifying D.altering30. A.Still B.Anyway C.Besides D.Nevertheless31. A.brand B.stuff modity D.produce32. A.this B.that C./ D.what33. A.into B.from C.in D.of34. A.long B.only C.first D.lonely35. A.distinctive B.distinct C.distinguished D.distinguishable36. A.possesses B.buys C.acquires D.grows37. A.exact B.identical C.same D.alike38. A.woks B.pots C.boilers D.fryers39. A.adequateely B.massively C.plentifully rgely40. A.flavour B.fragrance C.smell D.perfume2004The normal human daily cycle of activity is of some 7-8 hours’ sleep alternation with some 16-17 hours’ wakefulness and that the sl eep normally coincides(26) the hours of darkness. Our present concern is with how easily and to what extent this(27) can be modified.The question is no mere academic one. The ease with which people can change from working in the day to working at night is a(28)of growing importance in industry where automation(29) round-the-clock working of machines. It normally(30)from five days to one week for a person to adapt to a(31) routine of sleep and wakefulness, sleeping during the day and working at night. (32) it is often the case in industry that shifts are changed every week. This means that no sooner has he got used to one routine(33)he has to change to another, (34)much of his time is spent neither working nor sleeping very(35).One answer would seem to be(36) periods on each shift, a month, or even three months. (37), recent research has shown that people on such systems will revert to go back to their(38) habits of sleep and wakefulness duringthe week-end and that this is quite enough to destroy any(39) to night work built up during the week. The only real solution appears to be to hand over the night shift to those permanent night workers whose(40) may persist through all week-ends and holidays.26.A.in B.with C.of D.over27.A.cycle B.period C.circle D.round28.A.problem B.difficulty C.trouble D.matter29.A.asks B.invites C.calls for D.reacts to30.A.takes B.spends C.demands D.asks31.A.former B.returned C.reversed D.regular32.A.Therefore B.Unfortunately C.In a word D.In comparison33.A.as B.when C.then D.than34.A.though B.so that C.while D.as35.A.efficiently B.good C.easily D.happily36.A.shorter B.better C.longer D.nicer37.A.So B.In short C.Similarly D.However38.A.new B.normal C.temporary D.favourite39.A.change B.return C.adaptation D.tendency40.A.wakefulness B.sleep C.preference D.habit2005A person’s home is as much a reflection of his personality as the clothes he wears, the food he eats and the friends with whom he spends his time. Depending on personality, most have in mind a(n) “(31) ______ home”. But in general, and especially for the student or new wage earners, there are practical (32) of cash and location on achieving that idea.Cash (33) , in fact, often means that the only way of (34) when you leave school is to stay at home for a while until things (35) financially. There are obvious (36) of living at home—personal laundry is usually (37) done along with the family wash; meals are provided and there will be a well-established circle of friends to (38) . And there is (39) the responsibility for paying bills, rates, etc.On the other hand, (40) depends on how a family gets on. Do your parents like your friends? You may love your family—(41) do you like them? Are you prepared to be (42) when your parents ask where you are going in the evening and what time you expect to be back? If you find that you cannot manage a(n) (43) , and that you finally have the money to leave, how do you (44) finding somewhere else to live?If you plan to stay in your home area, the possibilities are (45) well-known to you already. Friends and the local paper are always (46) . If you are going to work in a (47) area, again there are the papers—and the accommodation agencies, (48) these should be approached with (49) . Agencies are allowed to charge a fee, usually the (50) of the first week’s ren t, if you take accommodation they have found for you.31. A. ideal B. perfect C. imaginary D. satisfactory32. A. deficiencies B. weaknesses C. insufficiencies D. limitations33. A. cut B. shortage C. lack D. drain34. A. getting over B. getting in C. getting back D. getting along35. A. improve B. enhance C. develop D. proceed36. A. concerns b. issues C. advantages D. problems37. A. still B. always C. habitually D. consequently38. A. call in B. call over C. call upon D. call out39. A. always B. rarely C. little D. sometimes40. A. little B. enough C. many D. much41. A. and B. but C. still D. or42. A. tolerant B. hostile C. indifferent D. good-tempered43. A. agreement B. consensus C. compromise D. deal44. A. go about B. go over C. go in for D. go through45. A. seldom B. less C. probably D. certainly46. A. dependent B. a good source of information C. of great value D.reliable47. A. familiar B. cold C. humid D. new48. A. though B. while C. since D. as49. A. enthusiasm B. hesitation C. caution D. concern50. A. same B. equivalent C. equal D. simiarity2006年七．There are many superstitions in Britain, but one of the most ( 31 ) held is that it is unlucky to walk under a ladder even if it means (32) the pavement into a busy street! (33) you must pass under a ladder you can (34) bad luck by crossing your fingers and (35) them crossed until you have seen a dog. (36) , you may lick your finger and (37) a cross on the toe of your shoe, and not look again at the shoe until the (38) has dried.Another common (39) is that it is unlucky to open an umbrella in the house-it will either bring (40) to the person who opened it or to the whole (41). Anyone opening an umbrella in fine weather is (42), as it inevitably brings rain!The number 13 is said to be unlucky for some, and when the 13th day of the month (43) on a Friday, anyone wishing to avoid a bad event had better stay (44). the worst misfortune that can happen to a person is caused by breaking a mirror, (45) it brings seven years of bad luck! The superstition is supposed to (46) in ancient times, when mirrors were considered to be tools of the gods. Black cats are generally considered lucky in Britain, even though they are (47) witchcraft.. it is (48) lucky if a black cat crosses your path-although in America the exact opposite belief prevails.Finally, a commonly held superstition is that of touching wood (49) luck. This measure is most often taken if you think you have said something that ist empting fate, such as “my car has never (50) , touch wood?”31. A broadly B widely C quickly D speedily32. A running from B jumping off C stepping off D keeping from33. A If B As C Though D Unless34. A erase B remove C avoid D ease35. A keep B keeping C kept D to keep36. A Consequently B However C Comparatively D Alternatively37. A make B print C perform D produce38. A label B symbol C mark D cut39. A argument B superstition C opinion D idea40. A loss B difficulty C tragedy D misfortune41. A house B household C home D circle42. A unwise B unintelligent C unpopular D unfortunate43. A falls B arrives C drops D happens44. A away B outdoors C indoors D far45. A when B as C if D though46. A have originated B be originating C be originated D originate47. A concerned about B related with C associated with D connected in48. A especially B specially C frequently D rarely49. A as B for C in D of50. A broken up B broken off C broken away D broken down2008年Salt, shells or metals are still used as money in out-of-the-way parts of the world today.Salt may seem rather a strange (31) to use as money, (32)in countries where the food of the people is mainly vegetable, it is often an (33) necessity. Cakes of salt, stamped to show their (34), were used as money in some countries until recent (35), and cakes of salt (36) buy goods in Borneo and parts of Africa.Sea shells (37) as money at some time(38) another over the greater part of the Old World. These were (39) mainly from the beaches of the Maldives Islands in the Indian Ocean, and were traded to India and China. In Africa, shells were traded right across the (40)from East to West.Metal, valued by weight, (41) coins in many parts of the world. Iron, in lumps, bars or rings, is still used in many countries(42) paper money. It can either be exchanged(43) goods, or made into tools, weapons, or ornaments. The early money of China, apart from shells, was of bronze, (44)in flat, round pieces with a hole in the middle, called "cash". The (45) of these are between three thousand and four thousand years old - older than the earliest coins of the eastern MediterraneaNowadays, coins and notes have (46) nearly all the more picturesque (47) of money, and (48) in one or two of the more remote countries people still keep it for future use on ceremonial (49) such as weddings and funerals, examples of (50)money will soon be found only in museums.(31) A. object B. article C. substance D. category(32) A. but B. and C. so D. even(33) A. abstract B. advantageous C. abundant D. absolute(34) A. weight B. value C. role D. size(35) A. times B. events C. situations D. condition(36) A. even B. also C. still D. never(37) A. had been used B. are used C. would be used D. would have been used(38) A. and B. but C. yet D. or(39) A. collected B. produced C. grown D. raised(40) A. city B. district C. communib D. continent(41) A. processed B. produced C. preceded D. proceeded(42) A. in spite of B. instead of C. along with D. in line with(43) A. against B. as C. in D. for(44) A. often B. seldom C. really D. much(45) A. earlier B.earliest C.better D.best(46) A. replaced B. reproduced C. reflected D. recovered(47) A. sizes B. shapes C. formats D. forms(48) A. while B. although C. because D. if(49) A. events B. gatherings C. occasions D. assemblies(50) A. original B. primitive C. historical D. crude2009年Scientists around the world are racing to learn how to rapidly diagnose, treat and stop the spread of a new, deadly disease. SARS -- Severe Acute Respiratory Syndrome --- was (31) for the first time in February 2003 in Hanoi, (32) since then has infected more than 1,600 people in 15 countries, killing 63. At this (33),there are more questions than answers surrounding the disease.Symptoms start (34) a fever over 100.4 degrees F, chills, headache or body (35). Within a week, the patient has a dry cough, which might (36) to shortness of breath. In 10% to 20% of cases, patients require (37)ventilation to breathe. About 3.5% die from the disease. Symptoms (38) begin in two to seven days, but some reports suggest it (39) take as long as 10 days. Scientists are close to (40) a lab test to diagnose SARS. In the meantime, it is diagnosed by its symptoms. There is no evidence (41) antibiotics or anti-viral medicines help, (42) doctors can offer only supportive care. Patients with SARS are kept in isolation to reduce the risk of(43) Scientists aren't sure yet, but some researchers think it's a (44) discovered coronavirus, the family of viruses that cause some common colds.Most cases appear to have been passed (45) droplets expelled when infected patients cough or sneeze. Family members of infected people and medical workers who care (46) them have been most likely to (47) the illness. But recent developments in Hong Kong suggest that the(48)might spread through air, or that the virus might (49) for two to three hours on doorknobs or other (50). Health experts say it is unlikely, though, that sharing an elevator briefly with an infected person would be enough to pass the virus.(31) A. detected B. caught C. disclosed D. revealed(32) A. but B. and C. or D. yet(33) A. time B. point C. aspect D. instance(34) A. from B. over C. upon D. with(35) A. hurt B. sore C. aches D. feelings(36) A. process B. advance C. progress D. convert(37) A. automatic B. artificial C. mechanical D. controlled(38) A. regularly B. ordinarily C. traditionally D. generally(39) A. will B. might C. should D. must(40) A. cultivating B. fostering C. developing D. designing(41) A. which B. that C. whether D. what(42) A. so B. but C. still D. yet(43) A. communication B. transportation C. transformation D. transmission(44) A. lately B. newborn C. newly D. renewed(45) A. under B. through C. beneath D. from(46) A. for B. over C. after D. about(47) A. acquire B. receive C. obtain D. contract(48) A. ailment B. ill-health C. disease D. infection(49) A. continue B. linger C. delay D. persist(50) A. exteriors B. outside C. surfaces D. coverings2010年How men first learned to invent words is unknown; (31) ____, the origin of language is a mystery. All we really know is that men, unlike animals, somehow invented certain (32) ____ to express thoughts and feelings, actions and things, (33) ____ they could communicate with each other; and that later they agreed (34) ____ certain signs, called letters, which could be (35) ____ to represent those sounds, and which could be (36) _____. Those sounds, whether spoken, (37) _____ written in letters, we call words.The power of words, then, lies in their (38) ____ the things they bring up before our minds. Words become (39) ____ with meaning for us by experience; (40)._____ the longer we live, the more certain words (41) _____ to us the happy and sad events of our past: and the more we (42) ____, the more the number of words that mean something to us (43) ____Great writers are those who not only have great thoughts but also express these thoughts in words which appeal (44) ____ to our minds and emotions. This (45)._____ and telling use of words is what we call (46) ____ style. Above all, the real poet is a master of (47) ____. He can convey his meaning in words which singlike music, and which (48) _____ their position and association can (49) ____ men to tears. We should, therefore, learn to choose our words carefully and use them accurately, or they will (50) ____ our speech or writing silly and vulgar.(31) A. in addition B. in other words C. in a word D. in summary(32) A. sounds B. gestures C. signs D. movements(33) A. such that B. as that C. so that D. in that(34) A. in B. with C. of D. upon(35) A. spelt B. combined C. written D copied(36) A. written down B. handed down C. remembered D. observed(37) A. and B. yet C. also D. or(38) A. functions B. associations C. roles D. links(39) A. filled B. full C. live D. active(40) A. but B. or C. yet D. and(41 ) A. reappear B. recall C. remember D. recollect(42) A. read and think B. read and recall C. read and learn D. read and recite(43) A. raises B. increases C. improves D. emerges(44) A. intensively B. extensively C. broadly D. powerfully(45) A. charming B. academic C. conventional D. common(46) A. written B. spoken C. literary D. dramatic(47) A. signs B. words C. style D. sound(48) A. in B. on C. over D. by(49) A. move B. engage C. make D. force(50) A. transform B. change C. make D. convert2000 BABDB CACDA CBDCD2001 BDDAB DBBCD AACAB2002 BADCA BDABC DADBA2003 CABAD CBDAA BCDDA2004 BADCA CBDBA CDBCD2005 AABAA CCABC BDBAD DDBCD2006 BCACB DACBD BDACB ACABD2008 CADBA CADAD CBDAB ADBCB2009 ABBDC ACDBC BADCB ADCBC2010 BACDB ADBAD BCBDA CBDAC。

连铸-CSATING

Copyright © 2003, The AISE Steel Foundation, Pittsburgh, P A.All rights reserved.123.1 IntroductionNear-net-shape casting of flat products is one of the true technological adventures that the steel industry has undertaken in the last 20 years.1–29The subject is still young,as only about 10 years have elapsed since the emergence of the first commercial near-net-shape casting technology—that being thin-slab casting. The literature on this subject is certainly abundant and oriented toward action,especially commercial action,but is more descriptive than analytical or critical. A review of this subject may therefore be both useful and necessary,but is limited in scope to a subjective presentation by this author due to the nature of the material available in the open literature.In spite of these difficulties,this chapter will endeavor to:•review the history of the field,•point out the strong development of the thin-slab casting concept,with due recog-nition of its present trends,which are moving it away from the initial mini-mill phi-losophy,and•offer some ideas about the potential of strip casting in advancing farther away from the classical integrated mill concept.23.2 A Short History of Near-Net-Shape CastingFig. 23.1 presents the recent history of near-net-shape casting for flat products.At the root of near-net-shape casting lies rapid solidification technology (RST),a young scientific discipline that emerged in the early 1970s. The filiation from RST to near-net-shape casting was never direct,as very few large-scale applications were developed in the megaton range of annual production,which is the plant scale of interest to the steel industry. The amorphous material that it produces might have displaced silicon steels for motor and transformer core applications,but this never materialized in spite of the efforts of Allied-Signal in the 1970s and 1980s.RST’s role in the steel industry in the early 1980s was mainly to show that near-net-shape casting might be a possible through its extension of conventional continuous casting.3,30–32The near-net-shape casting concept was first appropriated by integrated steel companies and by tech-nology providers such as the Hazelett Corp. in the U.S. to develop a tool for replacing conventionalChapter 23The Future of Continuous CastingJean-Pierre Birat, Manager, IRSIDCasting VolumeFig.23.1 A historical perspective on the near-net-shape casting of flat products.continuous casting and the roughing stands of the hot strip mill (HSM) on a quantitative production basis,i.e.,equipment for equipment. The idea was to change only the technology employed and con-tinue with business as usual in other areas of mill management. Casting between belts,a technology that had been quite successful in the nonferrous business,looked like it had the potential to fulfill this rather demanding agenda.After much money and time was spent on the concept in the U.S. (Hazelett,Nucor,U. S. Steel, Bethlehem Steel),in Japan (Kawasaki Steel,Nippon Steel) and in Europe (Ugine,Krupp Stahl),it became clear that the technology could not be brought up to the expected level,and it was all but abandoned.3At the same time that the twin belt technology was being pushed forward,the concept of strip cast-ing was being picked up as a working subject by a large number of research organizations all over the world. It was both a declaration of faith in the potential of innovation by the steel industry and a somewhat naive underestimation of the technological problems to be overcome. The agenda in this case was to do away almost completely with hot rolling and to replace the hot side of the steel mill with steelmaking and casting facilities. The concept today,after 20 years of research and development,is just emerging as commercially viable.Last in this historical schedule,but certainly not least in practical importance,is the thin-slab cast-ing concept launched by German equipment manufacturers in the 1980s. They were able to reach satisfactory results quickly and to commercialize the process at a time when the U.S. was in need of more steelmaking capacity,and when newcomers to the steel business there were bold enough to employ this technology to start their new businesses. Thin-slab casting today has turned out to be tremendously successful.The fascination with and success of near-net-shape casting technologies are certainly not limited to process and engineering viewpoints,but are closely related to the core business of the steel industry. One important aspect of this business connection is explained on the graph in Fig. 23.2, where the cost of building a greenfield steel mill is plotted on the vertical axis versus the specific cost per ton of annual steel capacity. For newcomers interested in commodity flat rolled steel pro-duction for a local market,the mini-mill is clearly a more attractive solution than an integrated mill. Integrated mills,which we may call the standard model of steel mills,had been successful since WWII in expanding the steel industry production capacity to meet the exploding demand for steel 2Copyright © 2003, The AISE Steel Foundation, Pittsburgh, PA.All rights reserved.The Future of Continuous CastingFig.23.2Mill models for flat products.due to economic growth in the rebuilt Western economies,as well as in nonindustrialized and non-developed countries. H owever,they require large capacities—several million tons per year—to reap the benefits of economies of scale,and large specific investment levels because of the com-plexity of the hot metal plant and the HSM.In the 1970s and 1980s,the mini-mill,which is a management concept based on matching a well-defined local market with lean production facilities capable of reactivity and flexibility,was look-ing for a technology to migrate from the long product to the flat product field.33–75Thin-slab casting is the technology that made this move possible. North America was the first geopolitical region of the world where the concept was extensively commercialized. It has since been utilized in the Pacific Rim as well as in Europe and in South America.23.3 Thin-Slab Casting76–229A review of thin-slab casting technology should explain why this particular technology was so rapidly successful and how far it has already evolved from the premises set forth 10 years ago by Nucor Steel at Crawfordsville,Ind.68–7523.3.1 Main Features of Thin-Slab CastingOne should initially stress the point that thin-slab casting is a direct extension of conventional con-tinuous casting. This is most certainly the reason why thin-slab casting could be developed into an actual production process in somewhat more than 10 years,which should be considered a short time for the steel industry,where 20 or 30 years are more representative of the time needed to induce a technology quantum leap.76–95Indeed,the world record on casting speed was obtained in Barrows,England,in the 1950s at 47.5 ft/min (14.5 m/min),and the major achievement of thin-slab casting was to make it safe and reli-able to cast at 13.0–19.5 ft/min (4.0–6.0 m/min). Initial solidification of the shell in thin-slab cast-ing,just as in conventional continuous casting,takes place by adding rings of shell to the thin slab, making use of an oscillating mold with a free meniscus,slag lubrication in the mold and continu-ous withdrawal of the product. The technologies needed to achieve reliable thin-slab casting were Copyright © 2003, The AISE Steel Foundation, Pittsburgh, PA.All rights reserved.3Casting Volumeall already imagined and had only to be further developed to reach the specific goals of thin-slab casting.Thin-slab casting is based on a number of complementary processes that must be applied together in order to establish a coherent production route:•Thin-slab casting will produce either thin slabs,from 1.5 to 2.75 inches (40 to 70 mm) in thickness,or medium-thickness slabs,from 3 to 6 inches (80 to 150 mm).•In-line reduction is then applied,either to the shell with a liquid core or to the solid slab.•The as-cast material must be homogenized in temperature and kept at the required enthalpy level in a special furnace type designed to accommodate its unusuallength,either a tunnel furnace or a hot-coiler.•Hot rolling can then be performed on the equivalent of finishing stands of a hot strip mill (HSM),or on a leaner mill such as a Steckel mill or a hot planetary mill. 23.3.2 Steelmaking for Thin-Slab CastingSteelmaking technologies,upstream from the caster,also need to be discussed in connection with thin-slab casting,as they are absolutely vital to the equilibrium of the whole process route (see Fig.23.3).The most common steelmaking route is the electric arc furnace meltshop,in that EAF technology has matured after important developments in the 1980s and still holds potential for further devel-opment.Scrap is the normal feedstock of the EAF,although people are recurrently nervous in the northern hemisphere about its availability,its price and its level of purity regarding tramp elements. It is com-plemented by small amounts of DRI or HBI,a favorite subject of conferences,which rather should be more concerned about scrap if they were to reflect the real importance of EAF raw materials.100 Thin-slab casting and an EAF are thus central to the new standard mini-mill,with CSP (Compact Strip Production) holding a large majority of the market share due to its being the first commeri-cialized process.101–124Fig.23.3 Processes upstream of the thin-slab caster.4Copyright © 2003, The AISE Steel Foundation, Pittsburgh, PA.All rights reserved.。

全新版大学英语视听阅读4视频听力原文

Narrator: Damage from swarms of locusts can reach disastrous proportions. A single swarm of desert locusts can consume over 70,000 metric tons of vegetation a day. There is, however, one continent that’s locust-free: North America.旁白：蝗虫群的伤害可以达到灾难性的程度。

一个单一的沙漠蝗虫可以消耗超过70000吨的植被一天。

然而，有一个大陆是蝗虫自由：美国北部。

Interestingly enough, this wasn’t always true. For hundreds of years, the Rocky Mountain locust was a common pest in the American West. Back in the mid-1800s, thousands of pioneers journeyed across the . in search of free land and new opportunities. They settled on the frontier of the western states, and began to farm the land intensively, growing corn and other crops.有趣的是，这并不总是真实的。

几百年来，落基山脉的蝗虫是美国西部的一种常见害虫。

早在19世纪中叶，成千上万的先驱者跨越美国在自由的土地和寻找新的机会。

他们定居在西部边境，并开始对土地进行集中耕种，种植玉米和其他农作物。

Then, in 1875, out of nowhere, a rare combination of air currents, drought, and basic biology produced the right conditions for an unthinkable event, the worst storm ever recorded, the “perfect swarm.” It came over the horizon like a strange, dark cloud. Not millions, not billions, but trillions of insects, sweeping through the land like a living tornado. Those who saw the incredible event and survived never forgot what they witnessed.然后，在1875，走出无处，一个罕见的组合，空气电流，干旱，和基本生物学产生了正确的条件为一个不可想象的事件，最坏的风暴有史以来，“完美的群”，它在地平线上像一个奇怪的，黑暗的云。

初中英语人教版八年级下册《Unit 7 What’s the highest mountain in

Unit 7 What’s the highest mountain in the world? 同步练习一、单项选择1. China has ____________ population in the world.A. moreB. the mostC. largerD. the largest2. ____________the boy is four, he can draw well.A. AlthoughB. SoC. Because ofD. Because3. You are too quiet. How I hope you can be ____________ outgoingA. a little moreB. too muchC. much tooD. much less4. There is a boy _________ in the river.A. swimB. swimmingC. to swimD. swam5. An elephant eats ___________ than a panda.A. many time moreB. many times muchC. many times moreD. much time more6. How tall he is! Yes，he is ____________than any other student in his class.”A. tallB. tallerC. the tallestD. tallest7. What is the way of ___________ animals?A. saveB. savedC. savingD. saves8. Mrs. Green missed her footing and __________ just now.A. fell overB. fell illC. fell forD. fell into9. It has stopped __________.A. rainB. to rainC. to rainingD. raining10. The Olympic Games are held (举行) ___________.A. every four yearB. each four yearC. each four yearsD. every four years11. There are many__________ in Sichuan.A. bamboo treeB. bamboo treesC. bamboos treeD. bamboos trees12. We should never give up ____________ others.Sometimes helping others means helping ourselves.A. to helpB. helpingC. helpedD. to help13. There were ____________people in the supermarket last Sunday that it was crowded(拥挤的).A. many tooB. too muchC. so manyD. so much14. It’s so cold today. Yes，it's __________ colder than it was yesterday.A. someB. moreC. veryD. much15. If farmers __________trees and forests, giant pandas _________ nowhere to live.A. cut down; haveB. will cut down; will haveC. will cut down; haveD. cut down; will have16. There are 8 keepers at the Chengdu Research Base. Two are young，and __________keepers.A. the othersB. the otherC. otherD. another17. These yellow dresses are very___________ hope to have.A. littleB. fewC. oneD. it18. The world's population is growing ______ and there is ______land and water for growing rice.A. more; lessB. larger; fewerC. larger; lessD. more; fewer19. Thanks for your invitation, but I'm so sorry I can't go. I need to _________ my baby at home.A. take awayB. take offC. take care oD. take out of20. I spent 5 $ __________ this book.A. inB. to buyC. buyingD. buy21. Do you think there __________ robots in people's homes in the future?A. will beB. will isC. be willD. will are22. We wear sunglasses __________the sun.A. ofB. atC. forD. from23. __________ exercise you take，you'll be ___________.A. The fewer; the fatterB. The less; the fatterC. The less; the more fatterD. The fewer; the more fatter24. Funtawild Adventure is very popular and ____________ tourists visit it year by year.A. more and moreB. fewer and fewerC. less and lessD. more or less25. Today it's normal for married to go out to work, but it was __________in the past.A. commonB. more commonC. less commonD. the most common26. I've got quite a few dictionaries. Among them, this English dictionary is ____________.A. much usefulB. more usefulC. the most usefulD. a little useful27. When and where were you born? I was born ________October 1st，1988 ________ Suzhou.A. on; onB. in; inC. on; inD. in; on28. This park is about 5000 square kilometers ____________size.A. onB. atC. ofD. in29. Liu Ying is as ____________ as her sister.A. tallB. tallerC. the tallest30. Do you know Lin Shuhao?Yes. He is one of ____________ basketball players in the NBA.”A. popularB. more popularC. the most popular二、完形填空AThe Great Wall of China is the longest wall in the world. The Great Wall has a history of over two ______ (1) years. People began to _______ (2) the wall between the Spring and Autumn Period in Chinese history. In about 221 BC Qin Shihuang had all the walls _________(3).From then on，the Great Wall came to the world. The Great Wall _________ (4) 6000 kilometers long and 6-7 meters high 4-5 meters wide. In most places it is _________ (5) enough for five horses or ten men to walk side by side along the top. It was very _________ (6) build _________ (7) a great wall in the old times. Thousands of men died when they built it. The Great Wall was made not only of stones，but millions of _______ (8)Today, the Great Wall has become a place _________ (9)interest not only to the Chinese but also to people all over the world. Just as the Egyptians feel proud of their pyramids, ________ (10)Chinese people also feel proud of our Great Wall.1. A. thousand B. million C. hundred D. billion2. A. create B. design C. form D. build3. A. made up B. joined up C. sent up D. put up4. A. no more than B. not more than C. less than D. more than5. A. wide B. long C. high D. tall6. A. easy B. difficult C. good D. bad7. A. like B. look C. so D. such8. A. alive B. live C. lives D. living9. A. of B. with C. for D. about10. A. us B. we C. our D. oursBProtecting wild animals is our duty. Because wild animals are important to us. They live with us on the earth together. If there are no animals on the earth, we will not live on, 1_________ So we should take good care 2__________ them to help us live a healthy life.3__________ some people still don't realize the 4__________ of protecting wild animals. They often kill wild animals for food or for money. Every day many wild animals being 5_________. So pots of animals have died out (灭绝).We can't see them any more. Today the number of wild animals 6__________ becoming smaller and smaller. If we don't here protect them, they will die out. If this goes on, the earth will be no animals left on the earth.7____________, more and more people have begun to do many things to help protect wild animals. They ask people 8___________ killing wild animals. They get people to know that protecting wild animals is one of the most important things. Now many countries have made 9____________ laws (法律)to protect wild animals. Now that (既然)wild animals are so man，we should do our 10_________to protect means human beings can make friends with get on well with them.1. A. too B. also C. neither D. either2. A. of B. off C. for D. from3. A. And B. But C. Or D. Although4. A. necessary B. importantly C. importance D. important5. A. killed B. killing C. kills D. kill6. A. was B. were C. are D.is7. A. Lucky B. Unlucky C. Luckily D. Unluckily8. A. stopping B. to stop C. stops D. stop9. A. much B. few C. some D. any10. A. well B. good C. better D. best三、阅读理解：ADo you know anything about the Great Wall? I visited it last summer and I want to tell you about it. The Great Wall of China is a national landmark that is famous around the world. And it is one of the seven wonders of the world. The Great Wall was first built about more than2，000 years ago. The emperor named Qin Shihuang let the working people build it. The main reason was to protect China. And other emperors continued building it. From Ming Dynasty，it is about 8，850 kilometers long. And it is the longest wall in the world. And now the famous part of the Great Wall is Badaling part of the Ming Great Wall. There is a saying，“He who has never been to the Great Wall is not a true man.” I think every Chinese should visit the Great Wall. It's the pride of our country.1. 文中画线部分的黑体字landmark的汉语:A.地标，里程碑B.记号C.土地标记2. What is the most famous part of the Great Wall?___________________________________________________________________.3. How long is the Great Wall?___________________________________________________________________.4. 把画线部分句子翻译成汉语。

2020年高考英语外刊时事命题阅读理解：《荒野间谍2》以独特视角真实的动物世界。Filming hidden wildlife

Filming hidden wildlife《荒野间谍2》以独特视角呈现最真实的动物世界。

For years, nature documentaries have given us an insight into the unseen wonders of the animal kingdom. Whether in the cold of the Arctic tundra (冻原) or the heat of the Sahara Desert, patient film crews equipped with tiny cameras and telephoto lenses have captured events that we can only dream of seeing.Returning for its second season, Spy in the Wild aims to give viewers an unparalleled (空前的) look into a hidden natural world. Commissioned (委托) by the BBC, the documentary follows the tradition of the first season while introducing camera technology that goes beyond the animal kingdom. With the help of innovative camera technology, a spy turtle can lay robot eggs; a spy squirrel can gather robot nuts; monkeys can play with a spy snowball and more.“Spy in the Wild 2 has more incredible animal behavior moments and firsts, while escalating (升级) the spy cam technology to a whole new level,” Fred Kaufman, executive producer for Nature, told BBC.In this season, more than 50 spy robots are allowed to explore animal groups in allkinds of territory, from under the Pacific Ocean to the harsh (严酷的) Arctic cold. But these undercover agents don’t just record everyday goings-on – they capture the relatable emotional connections shared between animals, first-hand. For example, a spy King penguin was accepted as part of the group in South Georgia. It watched on as penguin parents pushed their way through a barrier of 6,000 elephant seals in order to make it home to feed their chicks after a hunting expedition.“Quite accidentally, our spy creature is at the center of something extraordinary, capturing emotions that have rarely been observed,” the series’ narrator David Tennant told CNET.The documentary also won plaudits among critics. Brad Newsome of the Sydney Morning Herald wrote, “It’s right from the start as ingeniously (巧妙地) designed robot animals bring us incredibly intimate footage (详尽的镜头) of their flesh-and-blood counterparts (同类).”Spy in the Wild 2 shares rare footage of the animal kingdom. BBCSpeaking to PBS, the show’s director John Downer said: “The whole point is … trying to get closer than we ever have before to capture those elusive (难以得到的) moments when they start to reveal the kind of emotions we have.”（选自BBC）1. What is the main focus of the text?A. What inspired the creation of the show Spy in the Wild 2.B. How the documentary has been received.C. Cam technology and incredible footage of Spy in the Wild 2.D. Animals highlighted in the documentary.2. What can we learn about the spy robots in Spy in the Wild 2?A. Over 100 spy robots were involved in the documentary.B. They interacted with the animals.C. Some were destroyed in the process of filming.D. They recorded the animals’ lives from a distance.3. What does the underlined word “plaudits” in the second-to-last paragraph probably mean?A. praisesB. criticismsC. suggestionsD. arguments4. According to the text, what sets Spy in the Wild 2 apart from other nature documentaries?A. This is the first time spy robots have been used.B. It focuses on animals in a single territory.C. It captures relatable, emotional moments of animals.D. It explores common animal behavior frequently seen by the public.译文：多年以来，大自然纪录片使我们对动物界未见的奇观有了深刻的了解。

描写自然科学的英语作文题纲

描写自然科学的英语作文题纲Natural science is a vast and fascinating field that encompasses the study of the physical world around us. From the smallest subatomic particles to the grandest celestial bodies, natural science seeks to unravel the mysteries of the universe and deepen our understanding of the natural phenomena that shape our existence. In this essay, we will explore the breadth and depth of natural science, delving into its various disciplines and the ways in which it continues to transform our understanding of the world.At the heart of natural science lies the pursuit of knowledge through systematic observation, experimentation, and the rigorous application of the scientific method. This approach, which emphasizes objectivity, empiricism, and the testing of hypotheses, has led to groundbreaking discoveries that have revolutionized our understanding of the natural world. From the laws of motion that govern the movement of celestial bodies to the complex chemical reactions that sustain life, natural science has provided us with a profound and comprehensive understanding of the physical universe.One of the key disciplines within natural science is physics, the study of matter, energy, and their interactions. From the tiniest subatomic particles to the vast expanse of the cosmos, physics seeks to uncover the fundamental laws that govern the behavior of the physical world. Through the study of mechanics, thermodynamics, electromagnetism, and quantum mechanics, physicists have unlocked the secrets of the universe, from the creation of the stars to the nature of time and space.Another crucial field within natural science is chemistry, the study of the composition, structure, and properties of matter. From the elements that make up the periodic table to the complex molecules that form the building blocks of life, chemistry has provided us with a deep understanding of the chemical processes that shape our world. Through the study of organic and inorganic chemistry, as well as the development of new materials and technologies, chemists have played a vital role in advancing our knowledge and improving our quality of life.Closely related to physics and chemistry is the field of biology, the study of living organisms and the processes that sustain life. From the microscopic world of cells and microorganisms to the vast diversity of plant and animal life, biologists have uncovered the intricate mechanisms that govern the development, growth, and behavior of living beings. Through the study of genetics, evolution,ecology, and physiology, biologists have not only expanded our understanding of the natural world but have also made groundbreaking advancements in fields such as medicine, agriculture, and environmental conservation.Another important branch of natural science is earth science, which encompasses the study of the planet we call home. From the geological processes that shape the Earth's surface to the complex atmospheric and oceanic systems that govern our climate, earth science has provided us with a deeper understanding of the dynamic and ever-changing nature of our planet. Through the study of geology, meteorology, oceanography, and other related disciplines, earth scientists have made crucial contributions to our understanding of natural resources, natural disasters, and the long-term sustainability of our environment.Beyond the traditional disciplines of physics, chemistry, biology, and earth science, natural science has also expanded into a wide range of specialized fields, each with its own unique focus and methods of inquiry. For example, the field of astronomy explores the vast expanse of the universe, studying the formation, evolution, and behavior of celestial bodies such as stars, planets, and galaxies. Meanwhile, the field of materials science delves into the properties and applications of various materials, from the development of advanced composites to the design of cutting-edge technologies.Across all of these diverse fields, natural science is characterized by a common thread: the relentless pursuit of knowledge and the drive to understand the world around us. Through the use of scientific tools and methodologies, researchers in natural science are constantly pushing the boundaries of human understanding, uncovering new insights and challenging our existing assumptions.One of the most remarkable aspects of natural science is its ability to evolve and adapt to new discoveries and technological advancements. As our understanding of the natural world deepens, new fields of study emerge, and existing disciplines are continuously refined and expanded. This dynamic nature of natural science ensures that it remains at the forefront of human knowledge, constantly pushing the boundaries of what is known and inspiring new generations of scientists to explore the unknown.Moreover, the findings and discoveries of natural science have had a profound impact on our daily lives, shaping the way we live, work, and interact with the world around us. From the development of life-saving medical treatments to the creation of innovative technologies that improve our quality of life, the contributions of natural science are ubiquitous and far-reaching.In conclusion, natural science is a vast and multifaceted field thatcontinues to captivate and inspire us with its ability to unravel the mysteries of the physical world. Through the tireless efforts of researchers and the application of rigorous scientific methodologies, natural science has not only expanded our understanding of the universe but has also transformed the way we live and interact with our environment. As we continue to explore the frontiers of natural science, we can be certain that new discoveries and insights will continue to emerge, enriching our knowledge and inspiring us to delve deeper into the wonders of the natural world.。

the nature of scientific reasoning

本次翻译练习的难度比较大，文章出自北京师范大学研究生英语阅读与翻译课程所用的授课材料，作者布洛诺夫斯基是英国著名的数学家和散文家，剑桥大学数学博士。

这篇文章从科学发展史的角度出发，论述的问题主要是科学并不排斥想象力和创造力。

因此标题翻译成“科学理性的本质”或“科学推理的本质”是比较恰当的。

要翻译好这篇文章不仅应在在宏观的层面牢牢把握文章的主旨，也需要从微观的角度考虑作者使用的语言在语法和修辞上的特点，这样才能在理解的基础上恰当的表达。

当然，这篇文章相对于大家目前的英语水平，在理解和表达两个方面都具有不小的挑战性。

下面通过对这次翻译比较好的赵新平同学作业的点评，来分段落说一说这篇文章究竟有哪些细节部分需要注意，以及相应的翻译策略。

1What is the insight in which the scientist tries to see into nature? Can it indeed be called either imaginative or creative? To the literary man the question may seem merely silly. He has been taught that science is a large collection of facts; and if this is true, then the only seeing which scientists need to do is, he supposes, seeing the facts. He pictures them, the colorless professionals of science, going off to work in the morning into the universe in a neutral, unexposed state. They then expose themselves like a photographic plate. And then in the darkroom or laboratory they develop the image, so that suddenly and startlingly it appears, printed in capital letters, as a new formula for atomic energy.原译：什么是洞察力？科学家一直试图弄清它的本质。

2022考研英语阅读干细胞治疗

2022考研英语阅读干细胞治疗Stem-cell therapies干细胞治疗Prometheus unbound普罗米修斯自由了Researchers have yet to realise the old dream ofregenerating organs. But they are getting closer亘古以来，器官再生便是人类的夙愿。

如今讨论人员虽然还未真正实现，但胜利的脚步已经越来越近PROMETHEUS, a Titan bound to a rock by Zeus, endured the daily torture of an eaglefeasting on his liver, only to have the organ regrow each night.在希腊神话之中，提坦普罗米修斯被宙斯束缚在一块巨石之上，白天忍受着老鹰啄食他的肝脏，夜晚他的肝脏却又总会再次生长。

Compared with this spectacle, a video on the website of Nature this week seems decidedlydull.与生动的故事情节相比，本周《自然》网站上的一段视频就显得如此枯燥。

It shows a collection of pink dots consolidating into a darker central glob.这段视频向世人展现了很多粉红色的小点向中心聚集，成为一个颜色更深的团状物的过程。

But something titanic is indeed happening.但这正是普罗米修斯自由的曙光。

The pink dots are stem cells, and thevideo shows the development of a liver bud, something which can go on to look and act likea liver.那些粉红色的小点就是干细胞，而视频显示的正是肝芽生长的过程，并且这个肝芽可以进一步发育为，无论是外表还是功能都与肝脏类似的组织。

tpo40三篇托福阅读TOEFL原文译文题目答案译文背景知识

tpo40三篇托福阅读TOEFL原文译文题目答案译文背景知识阅读-1 (2)原文 (2)译文 (5)题目 (8)答案 (17)背景知识 (17)阅读-2 (20)原文 (20)译文 (23)题目 (25)答案 (35)背景知识 (35)阅读-3 (38)原文 (38)译文 (41)题目 (44)答案 (53)背景知识 (54)阅读-1原文Ancient Athens①One of the most important changes in Greece during the period from 800 B.C. to 500 B.C. was the rise of the polis, or city-state, and each polis developed a system of government that was appropriate to its circumstances. The problems that were faced and solved in Athens were the sharing of political power between the established aristocracy and the emerging other classes, and the adjustment of aristocratic ways of life to the ways of life of the new polis. It was the harmonious blending of all of these elements that was to produce the classical culture of Athens.②Entering the polis age, Athens had the traditional institutions of other Greek protodemocratic states: an assembly of adult males, an aristocratic council, and annually elected officials. Within this traditional framework the Athenians, between 600 B.C. and 450 B.C., evolved what Greeks regarded as a fully fledged democratic constitution, though the right to vote was given to fewer groups of people than is seen in modern times.③The first steps toward change were taken by Solon in 594 B.C., when he broke the aristocracy's stranglehold on elected offices by establishing wealth rather than birth as the basis of office holding, abolishing the economic obligations of ordinary Athenians to the aristocracy, and allowing the assembly (of which all citizens were equal members) to overrule the decisions of local courts in certain cases. The strength of the Athenian aristocracy was further weakened during the rest of the century by the rise of a type of government known as a tyranny, which is a form of interim rule by a popular strongman (not rule by a ruthless dictator as the modern use of the term suggests to us). The Peisistratids, as the succession of tyrants were called (after the founder of the dynasty, Peisistratos), strengthened Athenian central administration at the expense of the aristocracy by appointing judges throughout the region, producing Athens’ first national coinage, and adding and embellishing festivals that tended to focus attention on Athens rather than on local villages of the surrounding region. By the end of the century, the time was ripe for more change: the tyrants were driven out, and in 508 B.C. a new reformer, Cleisthenes, gave final form to the developments reducing aristocratic control already under way.④Cleisthenes' principal contribution to the creation of democracy at Athens was to complete the long process of weakening family and clanstructures, especially among the aristocrats, and to set in their place locality-based corporations called demes, which became the point of entry for all civic and most religious life in Athens. Out of the demes were created 10 artificial tribes of roughly equal population. From the demes, by either election or selection, came 500 members of a new council, 6,000 jurors for the courts, 10 generals, and hundreds of commissioners. The assembly was sovereign in all matters but in practice delegated its power to subordinate bodies such as the council, which prepared the agenda for the meetings of the assembly, and courts, which took care of most judicial matters. Various committees acted as an executive branch, implementing policies of the assembly and supervising, for instance, the food and water supplies and public buildings. This wide-scale participation by the citizenry in the government distinguished the democratic form of the Athenian polis from other less liberal forms.⑤The effect of Cleisthenes’ reforms was to establish the superiority of the Athenian community as a whole over local institutions without destroying them. National politics rather than local or deme politics became the focal point. At the same time, entry into national politics began at the deme level and gave local loyalty a new focus: Athens itself. Over the next two centuries the implications of Cleisthenes’ reforms were fully exploited.⑥During the fifth century B.C. the council of 500 was extremely influential in shaping policy. In the next century, however, it was the mature assembly that took on decision-making responsibility. By any measure other than that of the aristocrats, who had been upstaged by the supposedly inferior "people", the Athenian democracy was a stunning success. Never before, or since, have so many people been involved in the serious business of self-governance. It was precisely this opportunity to participate in public life that provided a stimulus for the brilliant unfolding of classical Greek culture.译文古雅典①在公元前800年到公元前500年期间，希腊最重要的变化之一是城邦的崛起，并且每个城邦都发展了适合其情况的政府体系。

中国珍稀大熊猫作文英语

The Giant Panda, a rare and precious species native to China, is widely recognized as a national treasure. With its distinct black and white fur, the panda is an iconic symbol of Chinas rich biodiversity. Heres a composition about the Giant Panda in English:The Majestic Giant Panda: A Symbol of Chinas Natural WondersIn the heart of Chinas lush forests, there exists a creature that has captured the hearts of people around the worldthe Giant Panda. Known scientifically as Ailuropoda melanoleuca, this species is not only a biological marvel but also a symbol of Chinas commitment to environmental conservation.Origin and HabitatThe Giant Panda is endemic to China, primarily residing in the mountain ranges of Sichuan, Shaanxi, and Gansu provinces. These regions provide the ideal habitat for pandas, with dense bamboo forests that serve as their primary food source. The pandas preference for a highaltitude environment, typically between 5,000 to 10,000 feet, sets it apart from other bear species.Characteristics and BehaviorThe Giant Panda is instantly recognizable by its striking colorationa blend of black and white that is as unique as it is beautiful. These colors not only serve as a form of camouflage in their natural habitat but also as a universal symbol of peace and harmony. Pandas are known for their gentle demeanor and their diet, which is almost exclusively bamboo, accounting for up to 99% of their food intake.Despite their large size, pandas are excellent climbers and swimmers, showcasing their agility and strength. They are also known for their playful behavior, often engaging in activities such as rolling down hills and frolicking in water.Conservation EffortsThe Giant Panda is listed as an endangered species, primarily due to habitat loss and a low reproductive rate. China has taken significant steps to protect these magnificent creatures. The establishment of nature reserves, such as the Wolong National Nature Reserve in Sichuan, has provided a safe haven for pandas and other wildlife.Moreover, China has been actively involved in international conservation efforts, partnering with other countries to expand the panda population through breeding programs. The租借 of pandas to foreign zoos, a practice known as panda diplomacy, has not only raised awareness about the species plight but also fostered global cooperation in wildlife preservation.Cultural SignificanceIn Chinese culture, the Giant Panda holds a special place. It is often depicted in art and folklore, symbolizing wealth and prosperity. The pandas image is also used in various national events and ceremonies, reflecting its status as a beloved national icon. ConclusionThe Giant Panda is more than just an adorable face it is a testament to the beauty and fragility of our natural world. As we continue to learn more about this species, it serves as a reminder of our responsibility to protect and preserve the environment for generations to come. The Giant Pandas story is one of hope, resilience, and the unwavering commitment of a nation to safeguard its natural heritage.This composition highlights the Giant Pandas unique characteristics, its importance in Chinese culture, and the ongoing efforts to ensure its survival in the wild. It is a tribute to the resilience of this species and a call to action for continued conservation.。

大学生就业困难的原因和解决措施英语作文

大学生就业困难的原因和解决措施英语作文全文共3篇示例，供读者参考篇1The Challenges of Finding a Job After University and Potential SolutionsAs a university student about to graduate, the prospect of entering the job market is both exciting and daunting. The transition from the structured world of academia to the professional realm is a significant milestone, and many of us are facing uncertainties and challenges in securing meaningful employment. The difficulties encountered by recent graduates in finding jobs are multifaceted, stemming from various economic, social, and personal factors. In this essay, I will explore some of the key reasons behind this predicament and propose potential solutions that could alleviate the struggle.One of the primary causes of the employment challenges faced by university graduates is the mismatch between the skills acquired during our education and the competencies demanded by employers. While universities strive to equip us with theoretical knowledge and academic prowess, the practicalapplication of these skills in the workplace often falls short of employer expectations. Many companies seek candidates with hands-on experience, problem-solving abilities, and soft skills such as communication, teamwork, and adaptability, which may not be sufficiently emphasized in traditional academic curricula.Furthermore, the ever-evolving nature of the job market and the rapid pace of technological advancements have created a disconnect between the skills taught in universities and those required in emerging industries. By the time we graduate, the knowledge and techniques we have acquired may already be outdated or insufficient to meet the demands of contemporary workplaces. This gap between education and industry needs can make it challenging for graduates to present themselves as attractive candidates to potential employers.Another significant factor contributing to the employment difficulties of university graduates is the oversupply of qualified candidates in certain fields. As more individuals pursue higher education, the competition for available job opportunities intensifies. Certain industries or professions may experience saturation, leading to an excess of applicants vying for a limited number of positions. This oversupply can drive down wages andmake it increasingly difficult for recent graduates to secure their desired roles or negotiate favorable employment terms.Economic conditions also play a crucial role in shaping the job market for university graduates. During periods of economic downturn or recession, companies may reduce their hiring efforts or implement job cuts, limiting the number of available positions. Fresh graduates often bear the brunt of these circumstances, as employers tend to prioritize experienced candidates with proven track records over those entering the workforce for the first time.Compounding these challenges is the lack of professional networks and industry connections among many university graduates. Networking and building relationships within one's desired field can significantly enhance job prospects, as personal connections often serve as gateways to employment opportunities. However, for those transitioning directly from university to the job market, establishing such networks can be arduous without prior work experience or professional contacts.While the challenges faced by university graduates in finding employment are multifaceted and complex, there are potential solutions that can alleviate these difficulties. One approach is to foster closer collaboration between universities and industrypartners. By incorporating internships, practical training, and industry-relevant projects into academic programs, students can gain valuable hands-on experience and develop the skills sought after by employers. Additionally, inviting industry professionals to guest lecture or serve as mentors can provide students with insights into real-world scenarios and facilitate networking opportunities.Universities can also prioritize the development of transferable skills, such as critical thinking, problem-solving, communication, and adaptability, alongside subject-specific knowledge. These skills are highly valued across various industries and can enhance graduates' employability, enabling them to navigate the ever-changing job market more effectively.Furthermore, career counseling and job placement services offered by universities can play a pivotal role in guiding students toward suitable career paths and connecting them with potential employers. By providing personalized guidance, resume workshops, and mock interviews, these services can better prepare graduates for the job search process and increase their chances of securing desirable positions.Encouraging entrepreneurship and self-employment among university graduates is another avenue worth exploring. Byfostering an entrepreneurial mindset and providing resources for business development, universities can empower graduates to create their own employment opportunities. This approach not only addresses the job scarcity issue but also promotes innovation and economic growth.Lastly, continuous professional development and upskilling should be emphasized to ensure that graduates remain competitive and adaptable in the ever-evolving job market. Universities can collaborate with industry partners to offerpost-graduate training programs, certifications, or online courses that allow graduates to enhance their skills and stayup-to-date with the latest industry trends and technologies.In conclusion, the difficulties faced by university graduates in finding employment are multifaceted and stem from various economic, social, and educational factors. By addressing the mismatch between academic curricula and industry needs, fostering industry-academia collaborations, emphasizing transferable skills, providing career guidance and networking opportunities, promoting entrepreneurship, and encouraging continuous professional development, we can better equip graduates for the challenges of the job market. It is a shared responsibility among educational institutions, employers, andindividuals to bridge the gap between education and employment, ensuring that the knowledge and skills acquired during university years translate into successful and fulfilling careers.篇2The Reasons for and Solutions to Employment Difficulties Faced by University StudentsAs a university student about to graduate, the looming question of securing employment weighs heavily on my mind and that of my peers. The transition from the academic world to the professional realm is often fraught with challenges, and finding a fulfilling job that aligns with our aspirations can be a daunting task. In this essay, I will delve into the multifaceted reasons behind the employment difficulties faced by university graduates and propose potential solutions to mitigate these challenges.Firstly, it is crucial to acknowledge the ever-increasing competition in the job market. With each passing year, the number of university graduates continues to rise, creating a surplus of qualified candidates vying for a limited number of available positions. This oversaturation of the job market can beattributed to the growing emphasis on higher education and the perception that a university degree is a prerequisite for success. Consequently, employers are inundated with applications, making it increasingly difficult for fresh graduates to stand out and secure their desired roles.Moreover, the disconnect between the skills acquired during academic studies and the practical requirements of the workforce often hinders employment prospects. While universities strive to provide a comprehensive education, there is a growing consensus that the curricula may not adequately prepare students for the demands of the modern workplace. Theoretical knowledge, while valuable, may not translate seamlessly into the practical application and problem-solving abilities sought by employers. This mismatch between academic training and industry expectations can leave graduates feeling ill-equipped to navigate the complexities of the professional world.Another contributing factor to employment difficulties is the rapidly evolving nature of the job market. The advent of new technologies, changing business models, and shifting economic landscapes have rendered certain skills and fields obsolete, while simultaneously creating demand for new and emergingprofessions. This dynamic environment poses a challenge for university students, as the knowledge and skills they acquire during their studies may become outdated by the time they enter the job market. Adapting to these ever-changing circumstances requires a proactive approach and a willingness to continuously learn and upskill.Furthermore, the lack of practical experience can be a significant barrier for fresh graduates seeking employment. Many employers prioritize candidates with relevant work experience, as it demonstrates their ability to apply theoretical knowledge in real-world scenarios and navigate the intricacies of a professional setting. Internships and co-op programs during academic studies can mitigate this issue, but not all students have access to such opportunities or the resources to pursue them.While the challenges outlined above may seem daunting, there are viable solutions that can alleviate the employment difficulties faced by university students. One crucial strategy is for universities to foster stronger collaborations with industry partners. By actively engaging with employers and seeking their input, academic institutions can better align their curricula with the needs of the workforce. This synergy can facilitate thedevelopment of practical, industry-relevant skills and provide students with opportunities for hands-on learning through internships, case studies, and real-world projects.Additionally, universities should prioritize the cultivation of transferable skills, such as critical thinking, problem-solving, communication, and adaptability. These versatile competencies are highly valued across various industries and can equip students with the ability to navigate the ever-changing job market. By emphasizing the development of these skills alongside subject-specific knowledge, universities can produce well-rounded graduates who are better prepared to tackle the challenges of the professional world.Career counseling and guidance services within universities also play a pivotal role in assisting students with their employment prospects. By providing personalized advice, resume-building workshops, and mock interviews, these services can empower students to effectively market themselves and stand out in the competitive job market. Additionally, fostering connections with alumni networks and industry professionals can open doors to valuable mentorship opportunities and potential job leads.Furthermore, students themselves must adopt a proactive mindset and take ownership of their professional development. Seeking out extracurricular activities, volunteering opportunities, and relevant part-time jobs can enhance their practical experience and demonstrate their commitment to personal growth. Continuously upskilling through online courses, workshops, or self-directed learning can also help bridge the gap between academic knowledge and industry requirements.In conclusion, the employment difficulties faced by university students are multifaceted and stem from various factors, including intense competition, skill mismatches, rapidly evolving job markets, and lack of practical experience. However, by implementing strategic solutions such as strengthening industry collaborations, emphasizing transferable skills, providing comprehensive career guidance, and fostering a proactive mindset among students, these challenges can be effectively mitigated. It is a shared responsibility between educational institutions, industry partners, and students themselves to work in tandem and ensure a smoother transition from the academic realm to the professional world. By embracing these solutions, we can pave the way for a more prepared and employable generation of graduates, ready to contribute their knowledge and skills to the workforce.篇3The Challenges of Finding a Job After University and Potential SolutionsAs a university student approaching graduation, the prospect of entering the job market is both exciting and daunting. While the completion of our degrees marks a significant achievement, it also brings with it the harsh reality of intense competition in the job market. The difficulties faced by recent graduates in securing employment are widely acknowledged, stemming from a multitude of factors that demand our attention and proactive approach.One of the primary reasons behind the employment struggles of university graduates is the oversupply of qualified candidates in relation to the available job opportunities. With an ever-increasing number of individuals pursuing higher education, the job market has become saturated, leading to a surplus of applicants vying for a limited number of positions. This imbalance between supply and demand has intensified the competition, making it more challenging for fresh graduates to stand out and secure their desired roles.Furthermore, the lack of practical experience often hinders the employability of recent graduates. While academic qualifications are undoubtedly valuable, employers increasingly seek candidates with hands-on experience and transferable skills that can be readily applied in the workplace. Internships andco-op programs provide opportunities for students to gain practical exposure, but not all educational institutions offer such opportunities, or students may face difficulties in securing these placements.Another significant factor contributing to the employment challenges faced by graduates is the mismatch between the skills acquired during their academic journey and the specific requirements of the job market. The rapid pace of technological advancements and evolving industry demands have created a gap between the curriculum taught in universities and the practical skills sought by employers. This disconnect can leave graduates ill-equipped to meet the expectations of potential employers, further exacerbating their struggles in securing employment.Economic conditions and market fluctuations also play a role in the employment prospects of university graduates. During periods of economic downturn or industry-specific challenges,job opportunities may become scarcer, intensifying competition and making it even more difficult for fresh graduates to secure employment. Additionally, global events, such as pandemics or geopolitical tensions, can disrupt job markets and create uncertainties that affect hiring practices.While the challenges faced by university graduates in finding employment are multifaceted and complex, there are proactive measures that can be taken to improve their prospects. One crucial step is for educational institutions to prioritize the development of practical skills and industry-relevant knowledge alongside theoretical learning. Integrating internships, co-op programs, and project-based learning into the curriculum can equip students with the hands-on experience and transferable skills that employers value.Collaboration between universities and industry professionals can also bridge the gap between academic curricula and real-world demands. By actively engaging with industry experts, educational institutions can gain insights into the specific skills and competencies required in various sectors, enabling them to tailor their programs accordingly. This collaboration can take the form of guest lectures, industry advisory boards, or even joint research initiatives, fostering asymbiotic relationship between academia and the professional world.Furthermore, universities should prioritize career counseling and job preparation services to better support students in their transition to the workforce. Career centers can provide guidance on résumé writing, interview skill s, networking strategies, and industry-specific insights. Additionally, organizing career fairs and facilitating connections with potential employers can open doors for students to explore job opportunities and make valuable professional connections.On an individual level, students can take proactive steps to enhance their employability. Actively seeking out internships, volunteering opportunities, or part-time jobs during their academic journey can provide valuable practical experience and demonstrate their commitment to personal and professional growth. Developing transferable skills such as effective communication, problem-solving, teamwork, and adaptability can also increase their appeal to potential employers.Moreover, students should be encouraged to engage in extracurricular activities, join student organizations, or participate in community initiatives. These experiences not only nurture their leadership abilities and soft skills but alsodemonstrate their well-roundedness and ability to balance multiple responsibilities – qualities that are highly valued by employers.Networking is another crucial aspect that should not be overlooked. Building professional connections through attending industry events, joining professional associations, or leveraging online platforms can open up potential job opportunities and provide valuable insights into different career paths. Additionally, maintaining relationships with professors, mentors, and alumni can unlock valuable advice, recommendations, and potential job leads.While the challenges faced by university graduates in securing employment are significant, they are not insurmountable. By addressing the root causes through collaborative efforts between educational institutions, industry professionals, and individual students, we can pave the way for a smoother transition from academia to the professional world. By prioritizing practical skill development, fosteringindustry-academia partnerships, and empowering students with career guidance and networking opportunities, we can better prepare graduates to navigate the competitive job market and unleash their full potential.As students, it is our responsibility to proactively seek out opportunities for personal and professional growth, cultivate a diverse set of skills, and remain resilient in the face of challenges. By embracing a mindset of continuous learning and adaptability, we can increase our chances of securing fulfilling employment opportunities and contribute positively to the workforce and society at large.。

描写熊猫动物的作文英语

The giant panda,scientifically known as Ailuropoda melanoleuca,is an iconic and beloved animal native to China.With its distinctive black and white fur,this gentle creature has captured the hearts of people around the world.Here is a detailed description of the giant panda,highlighting its physical characteristics,habitat,diet,behavior,and conservation status.Physical Characteristics:The giant panda is a large bear with a stocky body and a round head.It has large, distinctive black patches around its eyes,over its ears,and across its body.Its fur is thick and soft,providing insulation against the cold mountain climate.The pandas most notable feature is its black and white coat,which is not only visually striking but also serves as a form of camouflage in its natural environment.The pandas limbs are strong and short, with large paws that have an opposable thumb actually a modified wrist bone which aids in gripping bamboo while eating.Habitat:Giant pandas are found in the mountainous regions of central China,particularly in the provinces of Sichuan,Shaanxi,and Gansu.They inhabit dense bamboo forests at elevations ranging from5,000to10,000feet above sea level.The cool and misty climate of these highaltitude forests provides an ideal environment for the pandas and their primary food source,bamboo.Diet:Bamboo makes up over99%of a giant pandas diet.These animals are considered obligate bamboo feeders,meaning they rely almost exclusively on bamboo for their nutritional needs.A single panda can consume up to2838kilograms6284pounds of bamboo each day.Despite their large appetite,pandas have a relatively low metabolic rate,which is unusual for a bear of their size.Behavior:Giant pandas are generally solitary animals,coming together only during the mating season.They are nonaggressive and spend most of their day eating and sleeping.Pandas are also known for their playful behavior,often seen rolling down hills,climbing trees, and engaging in mock fights.They have a unique way of marking their territory,using scent from their肛glands to communicate with other pandas.Reproduction:Reproduction in giant pandas is challenging due to their low reproductive rates and specific mating behaviors.Female pandas are only fertile for a short period each year, making successful breeding a rare event.Cubs are born blind and helpless,weighing onlyabout100grams3.5ounces at birth.The mother panda will nurse and care for her cub for the first18months to2years.Conservation Status:The giant panda is listed as an endangered species on the IUCN Red List due to habitat loss,low birth rates,and a limited gene pool.Deforestation and human encroachment have reduced their natural habitat,leading to a decline in their population.However, conservation efforts,including reforestation and the establishment of nature reserves, have helped to stabilize and slowly increase their numbers.Cultural Significance:The giant panda is a national treasure in China and is often used as a symbol of diplomacy.Known as the panda diplomacy,China has given or loaned pandas to other countries as a sign of friendly relations.The pandas image is also widely used in Chinese culture and media,representing peace and friendship.In conclusion,the giant panda is a fascinating and unique species that faces significant conservation challenges.Its charm and rarity make it a symbol of wildlife conservation and a reminder of the importance of protecting our natural world.Efforts to preserve their habitat and increase their population are crucial for the survival of this remarkable animal.。

人类正在摧毁自然界概要写作讲义-2022届高考英语二轮复习

人类正在摧毁自然界概要写作讲义-2022届高考英语二轮复习一项重要的研究警告说，全球野生动植物种类和栖息地正在以“前所未有”的速度减少，这直接威胁到人类自身。

1. dramatically /drəˈmætɪk(ə)li / adv. 极大地2. unprecedented /ʌnˈpresɪdentɪd / adj. 前所未有的3. wither /ˈwɪðə(r) / v. （尤指渐渐）破灭;消失4. degradation /ˌdeɡrəˈdeɪʃn / n. 毁坏;恶化（过程）5. pollinate /ˈpɒləneɪt / v. 授粉A new United Nations assessment has concluded that humans are transforming Earths natural landscapes so dramatically that as many as one million plant and animal species are now at risk of extinction，posing a huge threat to ecosystems that people all over the world depend on for their survival.Its conclusions are worrying. In most major land habitats，the average abundance of native plant and animal life has fallen by 20 percent or more. With the human population passing 7 billion，activities like farming，logging，poaching，fishing and mining are altering the natural world at a rate unprecedented in human history.At the same time，a new threat has emerged. Global warming has become a major driver of wildlife decline by shifting or shrinking the local climates that many mammals，birds，insects，fish andplants evolved to survive in. When combined with the other ways humans are damaging the environment，climate change is now pushing a growing number of species，such as the Bengal tiger，closer to extinction.As a result，biodiversity loss is projected to accelerate through 2050，particularly in the tropics，unless countries drastically step up their conservation efforts.“For a long time，people have thought of biodiversity as saving nature for its own sake，” said Robert Watson，chair of the Intergovernmental Science Policy Platform on Biodiversity and Ecosystem Services. “But this report makes it clear that there’re links between biodiversity and nature and things like food security and clean water in both rich and poor countries.”But as these natural landscapes wither and become less biologically rich，the services they can provide to humans have been on the decrease.Humans are producing more food than ever，but land degradation is already harming agricultural productivity on 23 percent of the planets land area，the new report said. The decline of wild bees and other insects that help pollinate fruits and vegetables is putting up to $577 billion in annual crop production atrisk. The loss of mangrove forests and coral reefs along coasts could expose up to 300 million people to increased risk of flooding.Ⅰ. Difficult sentences1. A new United Nations assessment has concluded that humans are transforming Earths natural landscapes so dramatically that as many as one million plant and animal species are now at risk of extinction，posing a huge threat to ecosystems that people all over the world depend on for their survival.译文：联合国的一项新评估得出结论：人类正在极大地改变地球的自然景观，以致多达100万种动植物正面临灭绝的危险，这对全世界人民赖以生存的生态系统构成了巨大威胁。

RichardPreston_2008[理查德.普雷斯顿][巨人树]

尽管如此，还是有4%的原始红杉雨林保留了下来
rainforest remains intact, wild and now protected -- entirely 它们未受人类文明践踏，而且现在被保护了起来
protected -- in a chain of small parks strung out like pearls ——全面地被保护起来它们被保护于沿着加州北
[02:32]
It's a kind loaner from TED.
是从TED借来的。[02:40]
And Chris, if you could take the end of that tape measure? 克里斯，拿着卷尺的头好么?[02:42]
We're going to show you what the diameter at breast height 我们将要向你们展示一棵大型红杉在我们胸部高
of intense liquidation logging, clear-cutting that took place 砍伐，毁灭性的森林开垦活动中。[01:24]
in the 1970s through the early 1990s.
Even so, about four percent of the primeval Redwood

外语剧本网
The north coast of California has rainforests -- temperate 加州北部海岸有着一片片雨e it can rain more than 100 inches a year. 每年降水量超过25400毫米。[00:11]
I'm going to ask you to imagine what a Redwood really is as a 让你们去想象一下，一棵红杉作为一个生命体究竟

作文昆虫迷

作文昆虫迷英文回答：As an avid entomologist, I am captivated by theintricate world of insects. Their diverse forms, remarkable adaptations, and crucial ecological roles fascinate me endlessly. Growing up in a rural setting, I spent countless hours observing the myriad insect species that inhabited my surroundings. From the delicate wings of butterflies to the industrious ants, each species displayed a unique blend of beauty and complexity.My passion for entomology deepened during my undergraduate studies. I immersed myself in entomology courses, eager to unravel the secrets of insect anatomy, behavior, and ecology. Through field trips and research projects, I had the opportunity to observe insects in their natural habitats and conduct experiments to test hypotheses about their biology. Each new discovery fueled my enthusiasm and solidified my resolve to pursue a career inentomology.Currently, I am pursuing a graduate degree in entomology, where I am further honing my research skills and expanding my knowledge of insect taxonomy, physiology, and molecular biology. My research focuses on the impact of climate change on insect communities, a topic of critical importance given the current environmental crisis. By studying the responses of insects to changing climatic conditions, I hope to contribute to the development of conservation strategies and mitigate the negative effects of climate change on these essential organisms.The field of entomology offers a vast array of career opportunities, from academia to industry. As an entomologist, I could contribute to research, teaching, extension, or pest management. I am particularly drawn to the potential for collaboration and interdisciplinary research in entomology, which allows me to combine my passion for insects with other fields such as ecology, conservation, and public health.中文回答：作为一名狂热的昆虫学家，我被昆虫的复杂世界所吸引。

外刊每日精读 Bird numbers still falling

外刊每日精读 | Bird numbers still falling文章脉络【1】英国鸟类数量持续下降，除非做出彻底改变，否则英国将无法实现其保护自然的目标。

【2】2021年，英国政府通过了《环境法》，该法律要求到2030年阻止物种数下降。

【3】过去常见的物种出现了大幅度下降，我们的自然气候条件正处于紧急状态。

【4】认真正经、可持续的投资，对污染者的适当惩罚，以及政府各个领域的行动才能真正解决问题。

【5】英国鸟类数量是表明环境状况和自然界健康状况的一个关键指标，应当引起我们关注。

【6】鸟类已经得到良好研究，是研究野生动植物的重要研究对象。

Defra称已制定了明确的措施来改善野生动植物的生存状况。

经济学人原文Bird numbers still falling with Britain on course to miss its own wildlife targets【1】Bird populations in the UK continue to crash, new data shows,as campaigners predict the government will fail to meet its own nature targets unless radical changes are made.statistics released by the government show that bird populations continue to decline in the long and short term. In 2021, on averagethe abundance of 130breeding species was 12% below its 1970 value. Though muchof this loss was between the late 1970s and the late 1980s, caused mostlyby relatively steep declines in woodland and farmland birds, there was stilla 5% decrease between 2015 and 2020.Between 2015 and 2020, 24% of species increased, 28% showed little change and 48% declined. woodland birds continueto fare the worst, with a 12% decline.Wildlife experts agree that the decline in bird populations is largely driven by habitat loss.【2】The government passed the Environment Act into law in 2021, which requiresa halt in species decline by 2030. campaigners have said that radical changes to government policy are needed if it is to meet its own legally binding targets.The problems were highlighted by the RSPB’s Big Garden Birdwatch this year, in which house sparrows remained the most frequently observed species in gardens for the 20th year in a row.According to participants in the survey , about 1.5m house sparrows were seen in gardens between 27 and 29 January this year. Th is figure has droppedby nearly 60% since the survey began in 1979.【3】“The numbers speak for themselves when it comes to the startling declines of some of our once common birds,” said Beccy Speight, the RSPB’s chief executive. “They no longer have the abundance across the UK that they used to have. We are in a nature and climate emergency and we’ve lost38m birds from our skies in thepast 50years.”This year, more than 500,000 people took part in the Big Garden Birdwatch, and more than 9m birds were spotted. The resultsalso identified problems faced by other common bird species, including chaffinches and greenfinches.【4】Richard Benwell, the chief executive of the environmental coalition Wildlife and Countryside Link , said: “As political parties turn their sights to the general election, they would do well to heed the warning written into today’s wildbird statistics. The decline of nature has continued, relentless and unabated, for decades.“Meeting the legally binding target to stop wildlife losses by the end of the next parliament can’t be achieved with a legal tweak here, some spare change there. Serious, sustained investment, proper penalties for pollution, and action inevery sphere of government must be the hallmarks of any nature-positive manifesto.”【5】Dr Richard Gregory, the RSPB’s head of science , said: “Everyone should be concerned that UK bird populations are continuing to decline as this isa crucial indicator of the condition of our environment and health of our natural world. We cannot keep publishing report after report charting the decline of the UK’s wildlife without UK governments delivering on their commitments to take urgent action to restore nature and halt wildlife decline.“We are in a nature and climate emergency, and we need urgent action to keep common species common and save those already on the brink of being lost. ”He pointed out that the UK is “among the most nature-depleted countries in the world, bottom of the table compared to the rest of the G7” .【6】The Department for Environment, Food and Rural Affairs (Defra) said: “Bird populations have long been considered to provide a good indication of the broad state of wildlife in the UK. This is because they occupy a wide range of habitats and respond to environmental pressures that also operate on other groups of wildlife.“In addition, there are considerable long-term data on trends in bird populations, allowing for comparison between trends in the short term and long term. Because they are a wellstudied taxonomic group, drivers of change for birds are better understood than for other species groups, which enable better interpretation of any observed changes.”A spokesperson for Defra said: “Under theenvironmental improvement plan, we set out clear steps to halt the decline in species abundance by 2030 and improve the status of wild birds and other species which play an important role in our ecosystems. We are already taking robust action to reduce key pressures on wild birds and improve their habitats. ”。

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Critical nature of the giantﬁeld-induced pyroelectric response in Pb…Mg1/3Nb2/3…O3–x PbTiO3single crystalsS.I.Raevskaya,Yu.N.Zakharov,A.G.Lutokhin,A.S.Emelyanov,I.P.Raevski,M.S.Panchelyuga,V.V.Titov,and S.A.Prosandeev a͒Physics Department and Research Institute of Physics,Southern Federal University,Rostov-on-Don344090,Russia͑Received1June2008;accepted11July2008;published online30July2008͒We study the E-T phase diagram and dynamical pyroelectric coefﬁcient of an͑001͒-oriented ﬂux-grown0.8Pb͑Mg1/3Nb2/3͒O3–0.2PbTiO3single crystal.We found that the highest pyroelectric coefﬁcient can be achieved at the point having quasicritical features.These data establish a quasicritical behavior of theﬁeld-induced pyroelectric coefﬁcients in relaxors.©2008American Institute of Physics.͓DOI:10.1063/1.2966147͔The PbMg1/3Nb2/3O3–x PbTiO3͑PMN-x PT͒disordered relaxor lead magnesium niobate doped with ferroelectric lead titanate attracts much attention because of its remarkable di-electric,electrostrictive,and piezoelectric properties,which have extremely wide applications nowadays.1–3Modernﬁrst-principles computations relate the outstanding piezoelectric property in PMN-x PT to the polarization rotation.4It was realized recently that the piezoelectric properties of PMN-x PT can be enhanced even further if one applies an electricﬁeld moving the system toward a critical point.5The critical point has been found experimentally in both pure PMN͑Refs.6and7͒and PMN-x PT crystals.5,8The chal-lenge to enhance the piezoelectric properties is not unique. One may wish to improve and understand also the coupling to theﬁeld of other important physical properties such as pyroelectric.So far,this possibility has been hardly studied. However,one can eventuallyﬁnd in literature giant values of the pyroelectric coefﬁcients in samples of PMN-x PT and some relaxors subject to a biasﬁeld.9–12These high values were,ﬁrst,attributed to the secondary pyroelectric effect. However,precise studies carried out for0.55PMN-0.45PSN ceramics have shown that the secondary pyroelectric effect does not exceed12%of the overall response.12We supposed that the enhancement of the pyroelectric response of the re-laxors under dc bias can have a critical origin similar to the giant piezoelectric response.8But systematic studies of this point have not been conducted yet.The scope of the present paper is the study of the bias ﬁeld effect on the pyroelectric properties of an͑001͒-oriented PMN-0.2PT single crystal.This composition is well below the morphotropic phase boundary͑xϷ0.30–0.35͒,but it is ferroelectric at low T as evidenced by optical and x-ray dif-fraction studies.13,14We obtained extraordinary pyroelectric properties in this composition close to the point having a critical character.The connection of the pyroelectric property to the special points in the E-T phase diagram makes it pos-sible to explain and predict the appearance of the giant py-roelectric coefﬁcients in relaxors,and this can have obvious important applications.Single crystals of0.8PMN-0.2PT were grown at the In-stitute of Physics͑Southern Federal University,Rostov-on-Don,Russia͒using spontaneous crystallization from a PbO–B2O3ﬂux.15The crystals had a yellow color,the cubic shape with the edge lengths up to6mm and cube faces parallel to the͕001͖planes related to the perovskite unit-cell axes.The x value of the single crystal determined by using the x-ray microanalyser“Camebax Micro”equaled 0.20Ϯ0.015.Polished plates͑0.5–1.0mm thick͒,cut along the͑001͒perovskite plane and electroded with sputtered Pt, were used for measurements.The dielectric study was per-formed at the2K/min heating/cooling rate using a computer-controlled impedance analyzer E7-20.The pyroelectric coef-ﬁcient␥was measured by a dynamic technique similar to that described in Ref.12using a sinusoidal temperature modulation at a frequency of2–3Hz.The pyroelectric re-sponse was measured in the course of slow͑2–5K/min͒heating or cooling and was quantiﬁed by comparing with a reference sample of the multicomponent piezoelectric Pb͑Zr,Ti͒O3-based ceramic PCR-11with a known value of the pyroelectric coefﬁcient␥.Figure1͑a͒shows the temperature dependence of the permittivity␧measured in theﬁeld heating͑FH͒andﬁeld cooling͑FC͒modes for several biasﬁeld values.Both the temperature of the permittivity maximum T mϷ70°C͑at1 kHz͒and V ogel–Fulcher temperature T0Ϸ53°C are ap-proximately10°C lower than the previously reported data.14,16This fact can be explained by a small difference in the values of the concentration x in our samples.Notice that relaxors have distinct properties in the tem-perature interval above the V ogel–Fulcher temperature T0in comparison with the interval below this temperature.Indeed, the coupling between the glass order parameter q and polar-ization P shifts the Curie temperature down,T C=T C0−cq, where c is constant.This means that the glass order sup-presses ferroelectricity at zeroﬁeld.The effective electric nonlinearity constant␤also changes:␤͑E,T͒=␤0−gP2−␭q. In the͑001͒cut single crystals of PMN-x PT,it is common that when on cooling and at zeroﬁeld,␤0is positive because of the lattice anisotropy.17Underﬁnite biasﬁelds and/or be-low the V ogel–Fulcher temperature,the electric nonlinearity constant can become negative͑as this is seen in the expres-sion above͒.This can result in a jump of the dielectric per-mittivity corresponding to aﬁrst-order phase transition at ﬁniteﬁelds and/or q.a͒Also at Department of Physics,University of Arkansas,Fayetteville,AR72701,USA.Electronic mail:sprossan@.APPLIED PHYSICS LETTERS93,042903͑2008͒0003-6951/2008/93͑4͒/042903/3/$23.00©2008American Institute of Physics93,042903-1At zero bias ﬁeld,a marked change in the slope ͑CS ͒,which corresponds to a diffused ﬁrst-order-like phase transi-tion between the ferroelectric and relaxor phases,14,16is ob-served only in heating at about 55°C.The absence of such a CS in cooling can be ascribed to the slowing down of the relaxation kinetics below ϳ64–69°C.16Note that this tem-perature is close to the V ogel–Fulcher temperature.14The application of a rather small bias ﬁeld leads to the appear-ance of a CS in the ␧͑T ͒curve in the FC mode and makes the CS in ␧͑T ͒in the FH mode more distinct.Further increase in E shifts the CS in the ␧͑T ͒curves toward higher T ͑both on cooling and heating ͒results in its gradual diffusion and de-creasing of the temperature hysteresis width.The thermal hysteresis completely vanishes at E Ϸ1.3kV /cm.Above this point,the dielectric response has a diffused CS some-what below T m .The temperature dependence of the pyroelec-tric coefﬁcient ␥exhibits maxima at temperatures approxi-mately corresponding to the temperatures of the CS in the ␧͑T ͒curves ͓Fig.1͑a ͔͒.We draw attention to the fact that ␥͑T ͒has the same thermal hysteresis as ␧͑T ͒.In accord with this fact,the thermal hysteresis of ␥decreases toward the point,where the thermal hysteresis of ␧͑T ͒vanishes ͓Fig.2͑a ͔͒.Reversely,the magnitude of ␥increases toward thispoint ͓Figs.1͑b ͒and 2͑b ͔͒.It is natural to call this point critical,in analogy with the critical point in the theory of the liquid-gas phase transition.Above E =1.3kV /cm,the pyro-electric coefﬁcient decreases and the thermal hysteresis van-ishes ͓Fig.1͑b ͔͒.In this connection,the line in the E -T phase diagram,corresponding to the temperatures of the CS in the ␧͑T ͒curves at E Ն1.3kV /cm,is likely to be a so-called Widom line ͑the continuation of the ﬁrst-order phase transi-tion line above the critical point ͒.7Thus,our data establish the critical character of the pyroelectric coefﬁcient in the studied crystal.It is worth noting that the position of the critical point is at the connection of the Widom line with the ﬁrst-order phase transition lines ͓Fig.2͑a ͔͒.It is known that the maximum of ␧͑T ͒in relaxors largely depends on frequency and its temperature T m is not related to any phase transition.However,it is rather helpful to put the positions of T m on the E -T phase diagram in order to localize special points.8,18As one can see in Fig.2͑a ͒,T m ,at ﬁrst,slightly decreases as E grows,but above E Ϸ1.3kV /cm,begins to increase.The minimum in the T m ͑E ͒dependence is supposed to be close to the critical point in the E -T phase diagram.8,18Indeed,as one can see in Fig.2͑a ͒,it is close,although the presence of the V ogel–Fulcher temperature nearby can complicate the result.Our data deﬁnitely relate the maximum of the pyroelec-tric efﬁciency in PMN-0.2PT to the quasicritical behavior of-10010********20406080100ε·10-3;γ·104(C ·m -2.K -1)T (0C )11'2'23'345a2'12450102030405020406080100γ·104(C ·m -2·K -1)T (0C)12345bFIG.1.͑a ͒Temperature dependences of the permittivity at 1kHz ͑solid lines ͒and dynamic pyroelectric coefﬁcient ͑dashed lines ͒measured in the FH ͑1–5͒and FC ͑1Ј,2Ј,3Ј͒modes under different bias ﬁeld values,kV/cm:1,1Ј−0,2,2Ј−0.25,3,3Ј−0.3,4−1.3,and 5−2.1.The arrows mark the po-sition of the CS in the ␧͑T ͒curves.The ﬁgures at the arrows are the numbers of these curves.͑b ͒Temperature dependence of the dynamic pyroelectric coefﬁcient ␥measured in the FC mode under different bias ﬁeld values,kV/cm:1−0.1,2−0.65,3−1.3,4−2.1,and 5−3.2.204060800123T (0C )E (kV/cm)aT mFC FHCP20304050123γm ·104(C ·m -2·K -1)E (kV/cm)bE CPFHFCFIG.2.͑a ͒E -T phase diagram of the studied sample together with the dependence of T m on E .The T m ͑E ͒dependence is given by open squares.The positions of the CS in the ␧͑T ͒curves are shown by triangles.The temperatures of ␥͑T ͒maxima are presented by circles.The FC mode in the E -T phase diagram is marked by empty symbols and the FH mode is given by ﬁlled symbols.The lines are guides for the eye.͑a ͒The dashed line in the panel shows the supposed Widom line.The critical point is marked by CP.͑b ͒Field dependence of the maximal pyroelectric coefﬁcient values ␥m in the FH and FC modes.The arrow marks the value of the ﬁeld E CP corre-sponding to the critical point.the system close to the critical end point of 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