Preparation and characterization of cationic PLGA-PEGLf-DOPE nanoparticles for HO-1 gene delivery

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英语教学法程》王蔷复习题

英语教学法程》王蔷复习题陕西师范大学《英语教学法教程》复习题Unit 1 (3)Unit 2 (3)Unit 3 (3)Unit 4 (3)Unit 5 (4)Unit 6 (4)Unit 7 (4)Unit 8 (4)Unit 9 (4)Unit 10 (5)Unit 11 (5)Unit 12 (5)Unit 13 (5)Unit 14 (7)Unit 15 (7)综合复习题 (9)第三模块复习题Unit 1Views on languageViews on language learning1. What are the major views of language? What are their implications to language teaching or learning?2. Some language teachers argue that we should “teach the language” rather than “teach about the language”. What are the major differences between these two approaches tolanguage teaching?3. Audiolingual approach to language learning4.Socio-constructivist theory of language learning emphasizes interaction and engagement with the target language ina social context.5. The quality of a good language teacher includes ethic devotion, professional quality and personal styles.6. One influential idea of cognitive approach to language teaching is that students should be allowed to create their own sentence based on their own understanding of certain rules.Unit 2What is communicative compentence? Try to list some of its components.Principles in communicative language teaching/ strong version and week versionList some of the communicative activities.What is a task/its componentsUnit 3The overall language ability required in the 2001 National English Curriculum includes the following aspects language knowledge, language skills, learning strategies, affects and cultural understanding.4. Lesson PlanningWhat is lesson planning?Principles for good lesson planningComponents of a lesson planUnit 41. What is the Grammar-Translation Method?2.What is the Functional-Notional syllabus?3.What?s the di fference between Grammar-Translation Method and the Functional-Notional Approach?4. What is Sociolinguistics? Can you give some examples in your daily life?5. What is Language acquisition and language learning?6.What is the Natural Order of language acquisition?Unit 5What is classroom management?Types of student grouping and their advantages and disadvantagesThe role of the teacher ---- contoller, assessor, organizer, prompter, participant, resource providerThe new curriculum requires the teacher to put on the following new roles: facilitator, guides, and researchers.Classification of questionsHow to deal with errors?Unit 6Critical Period HypothesisThe goal of teaching pronunciation should be: consistency, intelligibility, and communicative efficiency.List some methods of practicing sounds.Unit 7Grammar presentation methodsGrammar practice is usually divided into two categories, mechanical practice and meaningful practice.Unit 8What does knowing a word involve? Receptive vocabulary and productive vocabulary.List some ways of presenting new wordsHow to consolidate vocabulary?Developing vocabulary building strategiesUnit 9Characteristics of listening processPrinciples and models for teaching listeningAs far as classroom procedures are concerned, the teaching of listening generally follows three stages: pre-listening stage, while-listening stage, and post-listening stage.Unit 10What are the characteristics of spoken language? Discuss their implications to teaching.Information-gap activitiesList some of the speaking tasks that the students are often asked to do in language classroomUnit 11The role of vocabulary in reading: sight vocabularySkills involved in reading comprehensionModels for teaching readingStages involved in Teaching ReadingProblems in reading are often seen as a failure to recognize words that may not exist in the learner’s vocabulary or in understanding grammatical structures that may not have been acquired by the learner. Therefore, the task of teaching reading is seen as teaching vocabulary along with the grammatical structure of the target language. Do you agree with such an opinion? Explain your reasons.In teaching reading, teachers often engage students in pre-reading, while-reading and post-reading activities. What do you think are the major functions of pre-reading activities?Unit 12What is the main idea of communicative approach to writing?What is the main idea of the process approach to writing?Unit 13I: What is the teacher?s role in communicativeLanguage teaching?I I: Decide which of the followings are “ traditional teaching methods” and which are communicative teaching methods”.1. The teacher tries to help them remember the meaning of each word by reading it mechanically again andagain.2. Students read the pattern drills aloud and then translate them one by one into Chinese. (or: first targetlanguage into mother tongue, then mother tongue into target language.)3. “Jigsaw” listening or reading--- the students read or listen to different texts, then they exchange with each other the information they have gained from them.4. The teacher refers to a picture，which everyone in the class can see and asks questions about the picture.5. Mini-research and questionnaires-students walk around the class to do a mini-investigation on certain topicthey are interested in by asking the other students question.6. The students read aloud the new words and expression by imitating their teacher or by listening to the tape.7. Students make sentences following the given pattern or sentence structure.8. Students present their own ideas or opinion on certain topic.9. Students read the text aloud.10. Students speak according to the roles assigned to them in a given situation11. Students do the written exercises, such as filling in the blanks with the correct forms of the verbs, adverbs, or prepositions, or they do multiple choice exercises .12. The text would be read aloud sentence by sentence and each one would be translated.13. The language is natural, so students will learn how speakers of the language actually use it.14. Students can learn more about the language by examining the discourse (how the text is organized and language is used to hold it together) and more about the background culture, which will help them comprehend future texts.15. The teacher teaches grammar rules. The teacher explains and illustrates them by pointing to examples in the text or by thing examples from dictionaries or grammar books.16. Real life is brought into the classroom, so that students are doing in class to what they might have to do later in life.17. The teacher then begins to deal with the text, sentence by sentence and paragraph by paragraph: explaining the language points, dwelling upon the grammar rules, analyzing the sentences, providing the Chinese equivalents, giving the examples to demonstrate the usage of certain words and expressions.18. Students in pairs are given different bits of information. By sharing this separate information they can completea task.19. Students in groups do debating, arguing about the advantage and disadvantage of T.V.20. The teacher then begins to deal with the text, sentence by sentence and paragraph by paragraph: explaining the language points, dwelling upon the grammar rules, analyzing thesentences, providing the Chinese equivalents, giving the examples to demonstrate the usage of certain words and expressions.III: Look at the following …role definitions? and the list of some a teacher?s functions. For each of these functions, decide which role is most appropriate ( in some cases more than one …role? may be involved)Rolesa. diagnosticianb. plannerc. managercontrollere. participantf. instructorg. assessorh. prompter1. to find out (as far and as consistently as possible the needs, interests, language difficulties and preferred learning styles of the students.2. to foster a group feeling(cooperation, liking, common aims, mutual confidence, etc)3. to ensure that learners have clear short and long-term learning objectives.4. to assess the progress of individual and of the class as a whole5. to ensure that learners are aware of this progress.6. to encourage students to take responsibility for their learning.7. to vary patterns of interaction within the lesson according to the precise aims and the nature/feeling of the group.8. to ensure that the students find their involvement sufficiently challenging.9. to analyse and present realistic …chunks? of the target language for students to process.10. to select and introduce activities and materials for language work.11. to help students develop positive, individual strategies for learning.Unit 141. What is bottom-up approach and top-down approach?2. What area the four main reading strategies? Describe their differences. When do you use these reading strategies?3. What?s pre-reading, while-reading and post-reading? What are their activities? Find a text and write pre-reading, while-reading and post reading activities.1． What is bottom-up approach and top-down approach?2．What area the four main reading strategies? Describe their differences. When do you use these reading strategies?3. what?s pre-reading, while-reading and post-reading? What are their activities? Find a text and write pre-reading, while-reading and post reading activities.Unit 15As a successful listener, he should be able to demonstrate his success by correctly reproducing the aural message, requires important information.The purpose for listening in real life are: :a. get informationb. to maintain social relationsc. to be entertained.Language and background knowledge constitute the two main sources of informationFor different purpose people use different listening skills;a. listening for a general ideab. listening for specific informationc. listening for detailed informationd. listening for inferring information ( listen to decode what is indirectly expressed, including the relationships between speaker, the moods or attitudes of the speaker, the physical setting of the text.e. note-takingGuidelines for designing effective listening tasks:a. the listening skill the students are required to developb. students? interests, needs, language level and potential problemsc. the class size, time available, teaching aidsDesigning tasks to develop the skill of listening for general ideaa. decide a titleb. write out the answersc. write a summaryd. look at a list of words and circle those used by the speakere. fill in blanksf. sequencing the main pointsconducting a listening classthe teacher can be thought of as a “director” and the students “actors”Task for director:a. gives an introductionb. monitor and observec. make comments or diagnose problemsthe t eacher?s role in listening class is just like director. A listening class is divided into three stages: pre-listening, while-listening and post-listening stages.Pre-listening stage a period before the students start listening. The main tasks of the pre-listening stage area. introduce about the topicb. introduce the type of the textc. introduce some background informationd. make predictions about the content and make a list of words which may occur in the listening text.While-listening stageIt is the period in which the students perform the act of listening. This is the stage in which students actually carry out all the activities while the teacher observes and operates the machine.The tasks in this stage are:a. listening for general ideab. listening for specific informationc. listening for inferringActivities:a. filling details in a formb. labeling a piece of graphic materialc. taking notesd. correcting something already writtene. ticking off items in a listf. drawing the picture or diagramg. carrying out actionsh. arranging events or information in the correct sequencei. judging whether some statements about the listening textare true or falsePost-listening stage: a period after listeningTasks:a. checks student?s answersb. points out their problemsc. explains the listening textd. oral summarye. written summaryf. create the situation for students to do role-playg. express your own view about the topic of the text.h. solve a given set of problems using the information you have learnt from the texti. hold discussion with your group on the topicj. write a letter to complain about the situation described in the listening text.k. write the same situation in your experience综合复习题Exercises for the course of English teaching methodologyI. Multiple choiceDirections：Choose the best answer for the following questions and write your answers on the answer sheet.1. What syllabus is designed around grammatical structures, with each lesson teaching a grammar structure, starting with simple ones, and progressing through to more complex ones?A. Structural syllabus.B. Situational syllabus.C. Functional syllabus.2. Which of the following is a communicative activity?A. Listen to the weather broadcast and fill in a form.B. Listen to the weather broadcast and talk about a picnic.C. Transfer the information from the weather broadcast intoa table.3. In which of the following situations is the teacher playing the role of a prompter?A. Explain the language points and meanings of words and sentences.B. Give examples of how to do an activity after the explanation and instructions.C. Elicit ideas from students.4. Which of the following is a social interaction activity?A. Information gap.B. Role-play.C. Information transfer.5. What reading approach is based on the assumption of reading as a guessing game?A. The top-down approach.B. The bottom-up approach.C. The interactive approach6. What reading strategy does the following activity help to train?The students were asked to read each paragraph and then match the paragraph with relevant headings.A. Inferring.B. Scanning.C. Skimming.7. Which of the pre-reading activities exemplifies the bottom-up approach?A. The teacher brings in pictures and asks the students to discuss in groups about the life of old people.B. The teacher raises several questions about old people andasks the students to discuss in pairs.C. The teacher presents a picture about the life of old people on the screen and brainstorm vocabulary related to old people?s life.8. What listening skill does the following activity help to train?Listen to the folio-wing text and answer the multiple-choice question.In this dialogue, the speakers are talking about________.A) going to a picnic B) attending a concert C) having a partyA. Listening for gist.B. Listening for specific information.C. Listening for detailed information.9. Which of the following features does spoken English have?A. It is generally produced in fairly simple sentence structures.B. It is produced with little redundancy.C. It is produced with good organization.10. What should a required lesson plan look like?A. a copy of explanation of words and structuresB. a timetable for activitiesC. transcribed procedure of classroom instruction11. For better classroom management, what should the teacher do while the students are doing activities?A. participate in a groupB. prepare for the next procedureC. circulate around the class to monitor, prompt and help12. Which of the following activities can best motivate junior learners?A. gamesB. recitationC. role-play of dialogues13. To cultivate communicative competence, what should correction focus on?A. linguistic formsB. communicative strategiesC. grammatical rules14. Which of the following activity is most productive?A. read the text and then choose the best answer to the questionsB. discuss on the given topic according to the text you have just readC. exchange and edit the writing of your partner15. To help students understand the structure of a text and sentence sequencing, we could use----- for students to rearrange the sentences in the right order.A. cohesive devicesB. a coherent textC. scrambled sentences16. The purpose of the outline------ is to enable the students to have a clear organization of ideas and a structure that can guide them .A. in the actual writingB. in free writingC. in controlled writing17. The grammar rules are often given first and explained to the students and then the students have to apply the rules to given situations. This approach is called .A. deductive grammar teachingB. inductive grammar teachingC. guiding discovery18. It is easier for students to remember new words if theyare designed in ------and if they are ------and again and again in situations and contexts.A. context, sameB. context, differentC. concept, difficulII. DefinitionDirections: Define the following terms1. Communicative compentence2. Lesson planning3. Classroom management4. Receptive vocabulary and productive vocabulary.5. Sight vocabulary6. Information-gap activities7. Display questions8. Task9. Audiolingual approach to language learning10.ReadingIII. Blank fillingDirections: fill in blanks according to what you?ve learn in the course of foreign language teaching.1. Socio-constructivist theory of language learning emphasizes interaction and engagement with the target language ina social context.2.The quality of a good language teacher includes ethic devotion, professional quality and personal styles.3.One influential idea of cognitive approach to language teaching is that students should be allowed to create their own sentence based on their own understanding of certain rules.4. The overall language ability required in the 2001 NationalEnglish Curriculum includes the following aspects language knowledge, language skills, learning strategies, affects and cultural understanding.5. The role of the teacher ---- contoller, assessor, organizer, prompter, participant, resource providerThe new curriculum requires the teacher to put on the following new roles: facilitator, guides, and researchers.6.The goal of teaching pronunciation should be: consistency, intelligibility, and communicative efficiency.7. Grammar practice is usually divided into two categories, mechanical practice and meaningful practice.8. As far as classroom procedures are concerned, the teaching of listening generally follows three stages: pre-listening stage, while-listening stage, and post-listening stage.IV. Problem SolvingDirections: Below are some situations in classroom instruction. Each has at least one problem. First, identify the problem(s). Second, provide your solution (s) according to what you have learned. You should elaborate on the problem(s) and solution(s) properly. Write your answer on the Answer Sheet.1．In one of the lessons. Mr. Li arranged the students into groups to talk about what they want to be when they grow up. To ensure that they applied what they learned, he required them to use the expressions in the text. To his surprise, students were not very active and some groups were talking about something else and one group was talking in Chinese.Problems:1) Maybe the topic does not correspond with the students? current needs. Suppose these students were interested only in getting high scores in examinations, they would not have interestin such a talk.2) The activity is much controlled. They may like to talk about their hobbies, but they have to use the expressions the teacher presents, which to some extent restricts them. That is perhaps why they are not very active.3) If students talk in Chinese, it may be because the talk is a little too demanding for them in terms of language competence. When students have difficulty in expressing themselves in English, they will switch to Chinese.4) Maybe the teacher does not arrange such activities very often in class. The students are not used to such communicative activities and so do not take an active part.Solutions:1）The teacher can ask the students to talk about their hobbies freely without considering the structure2) The teacher can give the task a real purpose. For example, he can ask the students to ask others about their hobbies to forma hobby club.3) It?s b etter to explain to the students the value of such kind of activity.4) The teacher can circulate around to encourage the students to talk in English.2. To cultivate communicative competence, Mr. Li chose some news reports from China Daily for his middle school students.Problems:1) Authentic materials are desirable in cultivation of communicative competence. But they should correspond to students" ability. News reports from China Daily are too difficult for middle school students.2) The content of news reports may not be relevant to the course requirement of middle school English.Solutions:1) If Mr. Li insists on using the materials from China Daily, it is necessary for him to adapt the material or select those reports which are easier to read and more relevant to students" interests.2) If he can, it is better to select news reports from other newspapers which are relevant to the students" life and study.It is necessary to bear in mind the students" needs when selecting materials for classroom instruction.(第一项要求写出两点即可，而第二项要求能说出两点。

Identification, isolation, synthesis and characterization of impurities

Aurobindo Pharma Ltd.Research Centre1,Bachupally,J.N.T.University2,Kukatpally,Hyderabad,India Identification,isolation,synthesis and characterization of impuritiesof quetiapine fumarateCh.Bharathi1,K.J.Prabahar1,Ch.S.Prasad1,M.Srinivasa Rao1,G.N.Trinadhachary1,V.K.Handa1,R.Dandala1, A.Naidu2Received May28,2007,accepted June18,2007Ramesh Dandala,Senior Vice-President,A.P.L.Research centre,313,Bachupally,Hyderabad500072,India rdandala@Pharmazie63:14–19(2008)doi:10.1691/ph.2008.7174In the process for the preparation of quetiapine fumarate(1),six unknown impurities and one known impurity(intermediate)were identified ranging from0.05–0.15%by reverse-phase HPLC.These impu-rities were isolated from crude samples using reverse-phase preparative HPLC.Based on the spectral data,the impurities were characterized as2-[4-dibenzo[b,f][1,4]thiazepine-11-yl-1-piperazinyl]1-2-etha-nol(impurity I,desethanol quetiapine),11-[(N-formyl)-1-piperazinyl]-dibenzo[b,f][1,4]thiazepine(impur-ity II,N-formyl piperazinyl thiazepine),2-(2-hydroxy ethoxy)ethyl-2-[2-[4-dibenzo[b,f][1,4]thiazepine-11-piperazinyl-1-carboxylate(impurity III,quetiapine carboxylate),11-[4-ethyl-1-piperazinyl]dibenzo[b,f][1,4] thiazepine(impurity IV,ethylpiperazinyl thiazepine),2-[2-(4-dibenzo[b,f][1,4]thiazepin-11-yl-1-piperazi-nyl)ethoxy]1-ethyl ethanol[impurity V,ethyl quetiapine),1,4-bis[dibenzo[b,f][1,4]thiazepine-11-yl]piper-azine[impurity VI,bis(dibenzo)piperazine].The known impurity was an intermediate,11-piperazinyl-dibenzo[b,f][1,4]thiazepine(piperazinyl thiazepine).The structures were established unambiguously by independent synthesis and co-injection in HPLC to confirm the retention times.To the best of our knowledge,these impurities have not been reported before.Structural elucidation of all impurities by spectral data(1H NMR,13C NMR,MS and IR),synthesis and formation of these impurities are dis-cussed in detail.1.IntroductionQuetiapine fumarate(1)is an antipsychotic drug belonging to the chemical class of dibenzothiazepine derivatives.It is used as a hemifumarate salt.Its IUPAC name is2-[2-(4-dibenzo[b,f][1,4]thiazepin-11-yl-1-piperazinyl)ethoxy etha-nol,(E)-2-butenedioate(2:1)salt.A literature survey re-vealed various methods for the synthesis of quetiapine(War-awa et al.2001).We synthesized the compound according to the Scheme(Warawa and Migler1989)with modifications to make it simpler and commercially viable.Its molecular formula is(C21H25N3O2S)2ÁC4H4O4and molecular weight is883amu as fumarate salt and383amu as base.HPLC methods(Saracino et al.2006;Mandrioli et al.2002) and a HPLC-electrospray ionization mass spectrometric method(Zhou et al.2004)were reported for the determi-nation of quetiapine in human plasma.During the preparation of1in the laboratory,six unknown impurities were detected in HPLC along with one known impurity.A comprehensive study was undertaken to iso-late,synthesize and characterize these impurities by spec-troscopic techniques.An impurity profile study is neces-sary for any final product to identify and characterize all the unknown impurities that are present in level of>0.1%. (ICH guideline,2005).The present study describes the isolation,synthesis and characterization of related impuri-ties of1.2.Investigations,results and discussion2.1.Detection and identificationQuetiapine fumarate was analysed by HPLC under the ana-lytical conditions described below.The chromatogram dis-played seven peaks at relative retention times compared to quetiapine at0.80,0.94,1.08,1.17,1.65,1.67and2.28. The LC-MS analysis showed six peaks having m/z values 339,323,427,323,411and504.They were isolated from crude samples of quetiapine by preparative HPLC.All the compounds were co-injected with quetiapine fumarate sam-ple in HPLC to confirm the retention times.HPLC chroma-togram of quetiapine fumarate spiked with all impurities is shown in the Fig.Synthesis and structural elucidation of these impurities are discussed in the following sections. Quetiapine fumarate was synthesized as shown in the Scheme,impurities I–VI were synthesized as described in the Experimental section and characterized.2.2.Characterization and origin of impurities2.2.1.Impurity IThe ESI mass spectrum of impurity I displayed the proto-nated molecular ion at m/z340.Therefore the molecular weight of this impurity was considered as339which was less by44amu than quetiapine.The odd molecular weightindicated the presence of odd number of nitrogens which in turn indicated the intactness of dibenzo[b ,f ][1,4]thia-zepine piperazinyl ring in this impurity structure.Pre-sence of broad signals at 3.70ppm (4H)and 4.34ppm (4H)in 1H NMR spectrum was attributed to piperazinyl ring.Two triplets were observed in impurity spectrum at 3.39ppm and 3.89ppm corresponding to 2ÂCH 2sig-nals instead of 4ÂCH 2groups present in the side chain of quetiapine.In 13C NMR two CH 2signals were ob-served at 61.1ppm and 73.1ppm instead of four CH 2signals.Based on the above spectral data observations,the structure of impurity I was characterized as 2-[4-di-benzo[b ,f ][1,4]thiazepine-11-yl-1-piperazinyl]l-2-ethanol (desethanol quetiapine).2-[2-Chloroethoxy]ethanol is a raw material for the pre-paration of quetiapine.2-Chloroethanol may be present as an impurity in this raw material.During the alkylation step in the preparation of quetiapine,alkylation of piper-azinyl thiazepine with the impurity,2-chloro ethanol leads to the formation of impurity I (desethanol quetiapine).2.2.2.Impurity IIESI mass spectrum of impurity II exhibited a protonated molecular ion peak at m/z 324,indicating the molecular weight as 323.The molecular weight of impurity II was 28amu more than that of the intermediate,4-piperazinyl di-benzo[b ,f ][1,4]thiazepine (2),m/z 295.MS fragmentation peaks were observed at m/z 296and 251.1H NMR spec-trum of this impurity showed signals similar to those of 2and in addition one new signal was observed at 8.13ppm integrated to one proton which was not exchangeable.This data suggested the attachment of a ––CHO group on piper-azine NH.Based on the spectral data,the structure of im-purity II was characterized as 11-[(N -formyl)-1-piperazi-nyl]-dibenzo[b ,f ][1,4]thiazepine (N -formyl piperazinylSNOHi.Piperazine /Toluene SNN N H i.2-(2-C hloroethoxy)ethanol ii.Na 2CO 3/NaI /NMP /TolueneSNNNO.2HClPiperazinyl thiazepine (2)SNNNOOHCOOHHOOC.Fumaric acid /Ethanol212345678910111213141516171819202122232223Quetiapine fumarate (1)SchemeSN NNOH34567891011121314151618192021Impurity I (Desethanol quetiapine)SN NNCHO56789101112131415161819202122Impurity II (N-Formyl piperazinyl thiazepine)221234N SNNOOOHO567891011121314151618192021Impurity III (Quetiapine carboxylate)3456789101112131415161718192021SN NNCH 3Impurity IV (N-Ethylpiperazinyl thiazepine)56789101112131415161718192021SNN NSN 9'10'11'12'13'14'15'16'18'19'20'21'Impurity VI (Bis (dibenzo)piperazine)N SNNOOCH 2CH 312345678910111213141516181920212223Impurity V (Ethyl quetiapine)thiazepine).This impurity arises when the alkylation of pi-perazinyl thiazepine with2-chloroethoxyethanol is carried out in N,N-dimethyl formamide.2.2.3.Impurity IIIESI mass spectrum of impurity III displayed a protonated molecular ion peak at m/z428,indicating the molecular weight of the compound as427which is44amu more than quetiapine.MS fragmentation peaks were observed at m/z,384,340and324.After thorough study of1H NMR and13C NMR spectra of this impurity,it was found to be as carboxy group attachment.It was observed from the1H NMR spectrum that there was no change in the number of protons compared to quetiapine and the signal correspond-ing to methylene protons attached to piperazine ring has shifted downfield from3.50ppm to4.14ppm.An addi-tional signal was observed at161.5ppm in the13C NMR spectrum and it was confirmed as quaternary carbon from DEPT experiment.From the above spectral data,the struc-ture of impurity III was characterized as2-(2-hydroxy ethoxy)ethyl-2-[2-[4-dibenzo[b,f][1,4]thiazepine-11-piper-azinyl-1-carboxylate(quetiapine carboxylate).This impurity arises when the alkylation of piperazinyl thiazepine is car-ried out in the presence of sodium carbonate(quetiapine carboxylate).2.2.4.Impurity IVESI mass spectrum of this impurity exhibited a protonated molecular ion peak at m/z324indicated the molecular weight of this impurity as323.Molecular weight of this impurity is28amu more than that of11-piperazinyl thi-azepine(intermediate).This odd molecular weight indicated the presence of odd number of nitrogen atoms which in turn indicated the intactness of piperazinyl thiazepine ring. MS fragmentation peaks were observed at296and253 amu.The signals corresponding to––O––CH2––CH2––OH group of quetiapine molecule were absent in impurity IV. Additionally,1H NMR spectrum of this impurity showed aFig.:LC-Chromatogram of Quetiapine fumarate samplespiked with impuritiesTable1:Comparative1H NMR assignments for quetiapine fumarate and its impuritiesPosition a Quetiapine fumarated(ppm),multiplicity Impurity-I d(ppm),multiplicityImpurity-II d(ppm),multiplicityImpurity-III d(ppm),multiplicityImpurity-IV d(ppm),multiplicityImpurity-V d(ppm),multiplicityImpurity-VI d(ppm),multiplicity1 3.43(t,2H)–––– 3.45(t,2H)–– 3.44(m,2H)––2 3.49(t,2H)–––– 3.47(t,2H)–– 3.52(m,2H)––3 3.55(t,2H) 3.82(t,2H)–– 3.61(t,2H) 1.29(t,3H) 3.56(t,2H)––4 2.52(t,2H) 3.27(t,2H)–– 4.14(t,2H) 3.18(t,2H) 3.40(t,2H)––5 6 7 82.50–2.54(brm,4H)and3.43–3.48(brm,4H)3.48and3.76(2brs,8H)3.42–3.73(m,8H)3.42and3.48(2brs,8H)3.20–3.75(brm,8H)3.20–3.75(brm,8H)3.03.65(brm,8H)9––––––––––––––10––––––––––––––117.55(m,1H)7.68(m,1H)7.55(d,1H)7.55(d,1H)7.68(m,1H)7.69(m,1H)7.56(m,2H)12 137.40(m,2H)7.60(m,2H)7.34–7.36(m,2H)7.44(m,2H)7.52–7.60(m,2H)7.52–7.60(m,2H)7.44–7.48(m,4H)147.45(m,1H)7.62(m,1H)7.42(d,1H)7.47(m,1H)7.62(m,1H)7.62(m,1H)7.46(m,2H) 15––––––––––––––16––––––––––––––177.37(dd,1H)7.54(dd,1H)7.40(dd,1H)7.38(dd,1H)7.54(dd,1H)7.54(dd,1H)7.38(dd,2H) 187.18(ddd,1H)7.35(brm,1H)7.23(ddd,1H)7.18(ddd,1H)7.35(brm,1H)7.35(brm,1H)7.20(ddd,2H)19 6.88(ddd,1H)7.15(ddd,1H) 6.95(ddd,1H) 6.91(ddd,1H)7.16(brd,1H)7.16(brd,1H) 6.90(ddd,2H)20 6.99(dd,1H)7.35(brm,1H)7.10(dd,1H)7.01(dd,1H)7.35(brm,1H)7.35(brm,1H)7.01(dd,2H) 21––––––––––––––22 6.62(s,2H)––8.13(s,1H)–––– 3.89(brm,2H)––23–––––––––– 1.08(t,3H)––s,singlet;d,doublet;dd,doublet of a doublet;ddd,doublet of a double doublet;m,multiplet;brs,broad singlet;brm,broad multiplet;q,quartet;t,tripleta Refor Scheme for numbering of quetiapine fumarateORIGINAL ARTICLEST a b l e 2:C o m p a r a t i v e13C N M R a n dDE P T a s s i g n m e n t s f o r q u e t i a p i n e f u m a r a t e a n d i t s i m p u r i t i e sP o s i t i o n a Q u e t i a p i n e f u m a r a t eI m p u r i t y -II m p u r i t y -I II m p u r i t y -I I II m p u r i t y -I VI m p u r i t y -VI m p u r i t y -V I13C d (p p m )DE P T13C d (p p m )DE P T13C d (p p m )DE P T13C d (p p m )DE P T13C d (p p m )DE P T13C d (p p m )DE P T13C d (p p m )DE P T161.1C H 2––––––––61.1C H 2––––66.4C H 2––––273.1C H 2––––––––73.1C H 2––––70.4C H 2––––368.7C H 258.6C H 2––––68.8C H 29.6C H 369.7C H 2––––457.8C H 256.1C H 2––––66.0C H 251.3C H 255.6C H 2––––567846.7a n d 53.44ÂC H 246.0,51.3a n d 51.64ÂC H 246.3,51.0a n d 51.64ÂC H 244.04ÂC H 246.4,50.0a n d 50.34ÂC H 245.751.4a n d 51.84ÂC H 245.5,47.6a n d 50.54ÂC H 29160.9––162.1––162.0––161.0––162.3––161.8––163.1a n d163.2––10139.6––136.5––140.0––139.6––140.6––140.3––137.8a n d137.9––11132.8C H 134.0C H134.0C H 132.8C H 134.1C H 133.5C H133.6a n d134.02ÂC H12129.8C H 130.2C H130.3C H 129.9C H 130.3C H 130.6C H130.2a n d130.44ÂC H13129.9C H 130.7C H 130.7C H 130.0C H 130.8C H131.3C H131.0C H14132.1C H 133.3C H 133.3C H 132.3C H 133.4C H 133.3C H 132.8C H 15128.1––128.0––––––128.1––127.7––127.5––129.0––16134.3––134.2––––––134.3––135.8––131.7––135.4––17132.9C H 135.1C H134.0C H 133.9C H 135.3C H 133.9C H134.7a n d134.92ÂC H18130.1C H 131.9C H 132.1C H130.2C H 132.0C H131.7C H 132.22ÂC H 19123.5C H 126.1C H126.4C H 123.8C H126.2C H126.6C H126.9a n d127.12ÂC H20126.0C H 129.5C H130.3C H 125.8C H129.7C H130.4C H128.9a n d129.22ÂC H21149.4––142.0––143.0––149.4––140.6––143.5––140.8––22135.2––––––162.3C H 156.0––––––65.5C H 2––––23167.4––––––––––––––––––9.6C H 3––––aR e f e r S c h e m e f o r n u m b e r i n g o f q u e t i a p i n e f u m a r a t e––CH3triplet at1.29ppm and––CH2quartet at3.18ppmcorresponding to ethyl group.This was supported by thepresence of methyl and methylene signals at9.0ppm and53.0ppm in13C NMR spectrum.Based on the above spectral data,the structure of impurity IV was character-ized as11-[4-ethyl-1-piperazinyl]dibenzo[b,f][1,4]thiaze-pine(N-ethyl-11-piperazinyl thiazepine).Ethanolic hydro-chloride was used to isolate piperazinyl thiazepine asdihydrochloride salt.Ethanolic hydrochloride may containethyl chloride which may alkylate piperazinyl thiazepineto yield this impurity(N-ethyl piperazinyl thiazepine).2.2.5.Impurity VESI mass spectrum of this impurity displayed a protonatedmolecular ion peak at m/z412indicating the molecularweight of this impurity as411which was28amu higher than that of quetiapine.Molecular weight suggested thatthe impurity was formed due to the substitution of ethylgroup on quetiapine.MS fragmentation peak was observedat324amu.In1H NMR spectrum of this impurity all the signals corresponding to quetiapine structure were presentand in addition methyl signal was observed as triplet at1.08ppm and methylene signal as quartet at3.53ppm.In 13C NMR spectrum the corresponding signals were ob-served at9.6ppm and65.5ppm.Based on the abovespectral data,the structure of impurity V was determinedas2-[2-(4-dibenzo[b,f][1,4]thiazepin-11-yl-1-piperazinyl)ethoxy]1-ethyl ethanol(ethyl quetiapine).2-[2-Chloro-ethoxy]ethoxy ethane may be an impurity present in theraw material,2-[2-chloroethoxy]ethanol.This impurityarises during alkylation of piperazinyl thiazepine with2-[2-chloroethoxy]ethoxy ethane(ethyl quetiapine).2.2.6.Impurity VIESI mass spectrum impurity VI exhibited a protonatedmolecular ion peak at m/z505,indicating the molecularweight of impurity as504.The even molecular weight suggested that the even number of nitrogens are present in this impurity.The molecular weight of this impurity was 209amu higher than that of piperazinyl thiazepine(quetia-pine intermediate,m/z,295).The difference molecular weight209amu corresponding to the dibenzo[b,f][1,4] thiazepine group.These mass values suggested that an-other dibenzo[b,f][1,4]thiazepine group was attached to piperazinyl NH of the quetiapine intermediate2.Sixteen aryl protons were present in the1H NMR spectrum,corre-sponding to two dibenzothiazepine groups and eight pro-tons were observed at3.4ppm,corresponding to one pi-perazine group.In13C NMR spectrum,the number of carbon signals in aryl region were doubled,supported the pre-sence of two dibenzo thiazepine groups.Based on the above spectral data,the structure of impurity VI was character-ized as1,4-bis[dibenzo[b,f][1,4]thiazepine-11-yl]piper-azine(bis(dibenzo)piperazine).During the preparation of piperazinyl thiazepine intermediate from11-chloro-diben-zo[b,f][1,4]thiazepine and piperazine,alkylation of both the nitrogen atoms of piperazine leads to the formation of bis(dibenzo)thiazepine.2.2.7.Spectroscopic dataThe1H and13C NMR chemical shift values of quetiapine fumarate and all impurities are presented in Tables1and2 FT-IR spectral data are given in Table3.3.Experimental3.1.Synthesis of the impuritiesThe investigated samples of quetiapine bulk drug and crude samples were synthesized in APL Research Centre(a unit of Aurobindo Pharma Ltd., Hyderabad,India).All impurities were isolated from crude samples by pre-parative HPLC.All the reagents used for analysis were procured from Merck(India)limited.3.1.1.Synthesis of impurity I,desethanol quetiapine hydrochloride11-Piperazinylthiazepine dihydrochloride(5g,0.0136mol)reacted with 2-chloro ethanol(1.2g,0.0149mol)in the presence of sodium carbonate (8.7g,0.0821mol),1-methyl-2-pyrrolidine(8ml,0.0771mol)and a cata-lytic amount of sodium iodide(0.05g,0.0003mol)in toluene(40ml)at 95–100 C for about24h and the reaction was monitored by TLC.Upon completion of reaction the reaction mass was washed with water (2Â25ml).The organic layer was concentrated completely under reduced pressure at50–55 C.The residue was dissolved in ethanol(40ml)and pH of the reaction mass was adjusted to$2.0with ethanolic HCl(10ml, $20%w/w).The precipitated product was filtered,washed with isopropy-lether(15ml)and dried at55–60 C to yield4.7g of desethanol quetia-pine.3.1.2.Synthesis of impurity II,N-formyl piperazinyl thiazepine11-Piperazinyl thiazepine dihydrochloride(10g,0.027mol),sodium carbo-nate(17.25g,0.163mol),sodium iodide(0.1g,0.0006mol)and2-chloro-Table3:FT-IR spectral data for quetiapine fumarate and its impuritiespound IR(KBr)absorption bands,(cmÀ1)1Quetiapine fumarate3320(m)OH stretch,3074,3014(w)aryl CH stretch,2946,2929,2898,2870(m)aliphatic CHstretch,1600,1573(s)aryl C¼C stretch and C¼N stretch,1414(s)CH2bend,795,768(m)aryl CHout-of-plane bend.2Impurity-I3060,3004(w)aryl CH stretch,2951,2884(m)aliphatic CH stretch,1622,1572(s)aryl C¼C stretchand C¼N stretch,1443(s)CH2bend,779,767(m)aryl CH out-of-plane bend.3Impurity-II3070(w)aryl CH stretch,2950,2890(m)aliphatic CH stretch,1620,1570(s)aryl C¼C stretch andC¼N stretch,1440(s)CH2bend,770,765(m)aryl CH out-of-plane bend.4Impurity-III3065(w)aryl CH stretch,2975,2886(m)aliphatic CH stretch,1620,1572(s)aryl C¼C stretch andC¼N stretch,1446(s)CH2bend,780,755(m)aryl CH out-of-plane bend.5Impurity-IV3063(w)aryl CH stretch,2979,2895(m)aliphatic CH stretch,1627,1573(s)aryl C¼C stretch andC¼N stretch,1430(s)CH2bend,782,767(m)aryl CH out-of-plane bend.6Impurity-V3070(w)aryl CH stretch,2923,2855(m)aliphatic CH stretch,.1621,1574(s)aryl C¼C stretch andC¼N stretch,1455(s)CH2bend,772,751(m)aryl CH out-of-plane bend.7Impurity-VI3052(m)aryl CH stretch,2989,2978,2953,2844(w)aliphatic CH stretch,1602,1575(s)aryl C¼Cstretch and C¼N stretch,1397(s)CH2bend,1245(s)C-N strech,1005,759,738(s)aryl CHout-of-plane bend.w–weak,s–strong,m–mediumethoxy ethanol(3.8g,0.03mol)were added to N,N-dimethylformamide (25ml)at room temperature.The reaction mass was heated to$100 C and stirred for8h while monitoring the process by HPLC.There after,the reaction mass was cooled to room temperature and poured into water (200ml).The product was extracted with ethyl acetate(2Â75ml)and the organic extract was washed with water(2Â80ml).The organic layer was concentrated completely under the reduced pressure at50–55 C.The resi-due contains$5%of this impurity which was isolated by preparative HPLC.3.1.3.Impurity III,quetiapine carboxylateImpurity III was isolated from mother liquors obtained during the prepara-tion of compound1.3.1.4.Synthesis of impurity IV,N-ethyl-11-piperazinyl thiazepine11-Piperazinyl thiazepine dihydrochloride(5g,0.0136mol)reacted with ethyl bromide(2.4g,0.020mol)in the presence of sodium carbonate (8.7g,0.0821mol)and dimethylformamide(15ml)at room temperature for2h and the reaction was monitored by TLC.The reaction mass was poured into water(200ml)and extracted with ethylacetate(2Â80ml). The organic layer was washed with water(2Â50ml)and concentrated completely under reduced pressure at50–55 C.The resulting residue was dissolved in ethanol(40ml)and treated with ethanolic HCl(10ml,20% w/w)at pH2.0.Isopropylether(20ml)was added dropwise to isolate the product.The product was stirred at room temperature for1h.The product was filtered,washed with isopropylether(5.0ml)and dried at55–60 C to yield4.2g of title compound.3.1.5.Impurity V,synthesis of ethyl quetiapineEthyl bromide(5.3g,0.0486mol)was added dropwise to a mixture of quetiapine fumarate(10g)and sodium hydroxide(2.9g,0.073mol)in dimethylformamide(50ml)at15–17 C.The reaction mass was stirred at15–20 C for8h and the reaction mass was monitored by HPLC until completion.Water(250ml)was added to the reaction mass and extracted with methylene chloride(2Â100ml).The organic layer was washed with water(2Â50ml)and concentrated under reduced pressure.The re-sidue was dissolved in ethanol(50ml)and ethanolic HCl(20ml,$20% w/w)was added dropwise.The precipitated product was stirred for1h. The product was filtered,washed with ethanol(5ml)and dried at40–45 C to yield6g of product containing$91%of the desired product by HPLC.3.1.6.Impurity VI,synthesis of bis(dibenzo)thiazepine11-Chloro-dibenzo[b,f][1,4]thiazepine(20.5g,0.0835mol)was added in small portions to a stirred mixture of piperazine(14.4g,0.167mol)in to-luene(160ml)at$50 C.The reaction was heated to$100 C,stirred for 4h and the reaction was monitored by HPLC until disappearance of start-ing material.The reaction mass was cooled to$20 C and filtered the salts.The toluene filtrate was washed with water(4Â100ml).The organic layer was concentrated completely under reduced pressure at50–55 C. The residue contains$12%of bis(dibenzo)thiazepine impurity which was isolated by preparative HPLC.3.2.High performance liquid chromatographyA Waters Alliance2695separation module equipped with2996photodiode array detector with Empower pro data handling system[Waters corpora-tion,MILFORD,MA01757,USA]was used.The analysis was carried out on YMC Pack-C8,150mm long,4.6mm i.d.,5m m particle diameter column.Mobile phase A was a mixture of phosphate buffer and acetonitrile in the ratio of90:10v/v,adjusted to pH6.7Æ0.05with dilute orthopho-sphoric acid solution(phosphate buffer was prepared by dissolving0.77g of disodium hydrogen orthophosphate(anhydrous)and0.57g of potassium dihydrogen orthophosphate in1000ml of water).Mobile phaseB was acetonitrile.UV detection was carried out at225nm and flow rate was kept at1.5ml/min.Column oven temperature was set at45C and data acquired for45min.Pump mode was gradient and the program was as follows,Time(min)/A(v/v):B(v/v);T0.01/80:20,T15.0/70:30,T25.0/60:40, T30.0/35:65,T35.0/30:70,T45.0/25:75,T50.0/80:20,T60.0/80:20.3.3.Preparative liquid chromatographyA Shimadzu LC-8A preparative liquid chromatograph equipped with SPD-10A VP,UV-Vis detector[Shimadzu corporation,Analytical Instruments Division,Kyoto,Japan]was used.Hyperprep HS C18(250mm longÂ21.2mm i.d.)preparative column packed with10m m particle size was em-ployed for isolation of impurities.The mobile phase consisted of(A) 0.1M ammonium acetate solution and(B)acetonitrile.Flow rate was set at20ml/min and UV detection was carried out at225nm.The gradient program was as follows,time(min)/A(v/v):B(v/v);T0.01/98:2,T20.0/90:10, T35.0/80:20,T50.0/70:30,T60.0/60:40,T75.0/50:50,T90.0/25:75.3.4.LC-MS/MS analysisLC-MS/MS analysis was carried out using a Perkin Elmer triple quadru-pole mass spectrometer(API2000,PE SCIEX)coupled with a Shimadzu HPLC equipped with SPD10AT VP UV-VIS detector and LC10AT VP pumps.Analyst software was used for data acquisition and data processing. The turbo ion spray voltage was maintained at5.5kv and temperature was set at375 C.The auxillary gas and curtain gas used was high pure nitro-gen.Zero air was used as nebulizer gas.LC-MS spectra were acquired from m/z100–1000in0.1amu steps with2.0s dwell time.The analysis was carried out using Hypersil BDS C18,150Â4.6mm column with5m m par-ticle dia.Mobile phase consisted of(A)0.01M ammonium acetate and(B) 1:1mixture of acetonitrile and methanol.UV detection was carried out at 225nm and flow rate was kept at1.5ml/min.Data acquisition time was 50min.The gradient program was as follows,Time(min)/A(v/v):B(v/v); T0.01/75:25,T5.0/75:25,T35.0/50:50,T40.0/15:85,T50.0/15:85.3.5.NMR SpectroscopyThe1H NMR,13C NMR(proton decoupled)and DEPT spectra were re-corded on Bruker300MHz spectrometer using DMSO-d6as solvent and tetramethylsilane(TMS)as internal standard.3.6.Mass spectrometryMass spectra were recorded on a Perkin Elmer PE SCIEX-API2000mass spectrometer equipped with a Turboionspray interface at375 C.Detection of ions was performed in electrospray ionisation,positive ion mode.3.7.FT-IR SpectroscopyFT-IR spectra were recorded as KBr pellet on a Perkin-Elmer instrument model––spectrum one.3.8.Isolation of impurities by preparative HPLCAll impurities were isolated by preparative HPLC from crude samples by using the conditions described above.Fractions collected were analyzed by analytical HPLC as per the conditions mentioned above.Fractions of >90%were pooled together,concentrated on Rotavapor to remove acetoni-trile.The concentrated fractions were passed through the preparative col-umn using water:acetonitrile(50:50)as mobile phase to remove the buf-fers used for isolation.Again the eluate was concentrated in a Rotavapor to remove acetonitrile.The aqueous solutions were lyophilized using freeze dryer(Virtis advantage2XL).Acknowledgements:The authors gratefully acknowledge the management of Aurobindo Pharma Limited,for allowing us to carry out the present work.The authors are also thankful to the colleagues of Analytical Re-search Department(ARD)and Chemical Research Department(CRD)for their co-operation.ReferencesICH Guideline Q3A(R2).Impurities in new drug substances,25October 2006.Mandrioli R,Fanali S,Ferranti A,Raggi MA(2002)HPLC analysis of the novel antipsychotic drug quetiapine in human plasma.J Pharm Biomed Anal30:969–977.Saracino MA,Mercolini L,Flotta G,Albers LJ,Merli R,Raggi MA (2006)Simulataneous determination of fluvoxamine isomers and que-tiapine in human plasma by means of HPLC.J Chromatogr843:227–233.Warawa EJ,Migler BM(1989)Novel dibenzothiazepine patent4,879,288.Warawa EJ,Migler BM,Ohnmacht CJ,Needles AL,Gatos GC,McLaren FM, Nelson CL,Kirkland KM(2001)Behavioral approach to nondyskinetic dopamine antagonists:identification of seroquel.J Med Chem44:372–389.Zhou Z,Li X,Li K,Xie Z,Cheng Z,Peng W,Wang F,Zhu R,Li H (2004)Simultaneous determination of clozapine,olanzapine,risperidone and quetiapine in plasma by HPLC-electrospray ionization mass spectro-metry.J Chromatogr802:257–262.。

Preparation and Characterization of La0.8Sr0.2MnO3-δ Cathode for SOFCs Fabricated Using Azeotro

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Synthesis and Characterization of Li(Li0.23Mn0.47Fe0.2Ni0.1)O2 Cathode Material for Li-ion Batteries

retention
Li(Li0.23Mn0.47Fe0.2Ni0.1)O2 compound synthesized easily at low temperature by the proposed citric acid assisted sol-gel process is a promising cathode material for Li-ion batteries.
57
EP
TE D
(1−z)Li[Li1/3Mn2/3]O2−(z)Li[Mn0.5−yNi0.5−yCo2y]O2
M AN U
[11]. to
2
Li2MnO3–LiCo1/3Ni1/3Mn1/3O2
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The 4.0~4.5V)
storage power station applications. Therefore, new cathode materials with high capacity, low cost and environment friendly have been investigated thoroughly in recent years [1]. Among them the layered Li2MnO3-based solid solution materials have attracted more attention of the researchers, such as Li2MnO3-LiMO2 (M = Ni, Cr and Co) [2–5], LiNiO2–Li2MnO3–LiCoO2 [8], and [6], Li2MnO3–LiNi1−xCoxO2 [7], [9], [10], above-mentioned

曹胖学位英语分享

曹胖学位英语分享IntroductionIn the vast expanse of linguistic studies, English has emerged as a global lingua franca, opening doors to international communication, academia, and professional opportunities. Cao Pang, a distinguished scholar and enthusiast for the English language, has embarked on a journey to share his insights and experiences in mastering English for academic purposes. This document serves as a comprehensive guide, detailing Cao Pang's approach to learning English, strategies for success, and the benefits of obtaining an English degree.The Importance of English in Academia1. Global Communication: English is the primary language of international discourse, making it essential for scholars to communicate their research findings to a broader audience.2. Access to Literature: A significant portion of academic literature is published in English, necessitating proficiency for comprehensive access to scholarly work.3. Collaboration Opportunities: English facilitates collaboration across borders, allowing researchers to work with peers from different countries.Cao Pang's JourneyCao Pang's path to fluency in English was marked by dedication and a strategic approach to learning. Here's an overview of his journey:1. Foundation Building: Cao began with a strong foundation in grammar and vocabulary, using textbooks and online resources to build a solid base.2. Immersive Learning: He immersed himself in English by watching English-language films, listening to podcasts, and engaging in conversations with native speakers.3. Academic Focus: Recognizing the importance of academic English, Cao specialized in reading and writing skillscrucial for scholarly articles and discussions.4. Degree Pursuit: Cao pursued a degree in English, which not only honed his language skills but also provided a deep understanding of English literature and culture.Strategies for English LearningCao Pang advocates the following strategies for effective English learning:1. Consistent Practice: Regular engagement with the language is key to improvement.2. Diverse Sources: Utilize a variety of learningmaterials, including books, videos, and interactive online platforms.3. Active Participation: Engage in discussions, debates, and public speaking to enhance speaking and listening skills.4. Cultural Immersion: Understanding the cultural context of the English language can enhance language acquisition.5. Feedback Loop: Seek constructive feedback and be open to correction to refine language skills.Benefits of an English DegreeAn English degree offers numerous benefits, including:1. Enhanced Communication Skills: Adeptness in English allows for effective communication in diverse settings.2. Broadened Career Prospects: Many fields, from education to international business, value professionals with strong English skills.3. Cultural Literacy: An English degree fosters an appreciation for literature and cultural nuances of English-speaking countries.4. Critical Thinking: Analyzing complex texts and ideasis a hallmark of English studies, developing criticalthinking abilities.5. Research Skills: The degree equips students with the skills necessary to conduct thorough research and present findings effectively.Challenges and SolutionsLearning English, especially for academic purposes, can present challenges:1. Pronunciation: Cao recommends using pronunciation guides and practicing with native speakers.2. Vocabulary: Building a robust vocabulary is essential. Cao suggests using flashcards and engaging with diverse texts.3. Writing Skills: Academic writing requires a specific style and structure. Cao emphasizes the importance ofstudying exemplary texts and seeking feedback.4. Cultural Differences: Understanding culturalreferences can be challenging. Cao encourages learners to explore English-speaking cultures through media andliterature.ConclusionCao Pang's English degree sharing underscores the transformative power of language proficiency. His journey and the strategies he shares provide a roadmap for othersaspiring to master English for academic and professional success. As English continues to be a vital tool in theglobalized world, Cao's insights serve as a valuable resource for those on a similar path.References- Brown, H. D. (2017). _Teaching by Principles: An Interactive Approach to Language Pedagogy_. Pearson.- Crystal, D. (2015). _The Cambridge Encyclopedia of the English Language_. Cambridge University Press.- Hyland, K. (2009). _Academic Discourse: English in a Global Context_. Continuum.This document is structured to provide a clear and comprehensive overview of Cao Pang's experiences and advice regarding the pursuit of an English degree. It is written in a formal and informative tone, suitable for an academic or professional audience interested in English language studies.。

Development and Characterization of a Cell Culture Manufacturing Process Using Quality

Development and Characterizationof a Cell Culture Manufacturing ProcessUsing Quality by Design (QbD)PrinciplesDaniel M.Marasco,Jinxin Gao,Kristi Grifﬁths,Christopher Froggatt,Tongtong Wang and Gan WeiAbstract The principles of quality by design (QbD)have been applied in cell culture manufacturing process development and characterization in the biotech industry.Here we share our approach and practice in developing and char-acterizing a cell culture manufacturing process using QbD principles for establishing a process control strategy.Process development and character-ization start with critical quality attribute identiﬁcation,followed by process parameter and incoming raw material risk assessment,design of experiment,and process parameter classiﬁcation,and conclude with a design space con-struction.Finally,a rational process control strategy is established and documented.Keywords Cell culture process characterization ÁCell culture process develop-ment ÁCell culture process scale-up ÁControl strategy ÁCritical quality attribute ÁDesign space ÁQuality by design ÁRisk assessment AbbreviationsQbDQuality by design QTPPQuality target product proﬁle CQACritical quality attributes DOEDesign of experiment CPMControl point matrix FMEA Failure modes and effects analysisD.M.Marasco (&)ÁJ.Gao ÁK.Grifﬁths ÁC.Froggatt ÁT.Wang ÁG.WeiBioproduct Research and Development,Lilly Research Laboratories,Eli Lilly and Company,Indianapolis,IN 46285,USAe-mail:marasco_daniel_m@Adv Biochem Eng Biotechnol (2014)139:93–121DOI:10.1007/10_2013_217ÓSpringer-Verlag Berlin Heidelberg 2013Published Online:5July 201394 D.M.Marasco et al. Contents1Introduction (94)2Development and Characterization of Cell Culture Manufacturing Process for Establishing a Process Control Strategy (96)2.1Construct CQA(s)Control Points Matrix (96)2.2Initial Process Parameter Risk Assessment (98)2.3Risk Mitigation/Initial Process Characterization Experiments (101)2.4Final Characterization Experiment (106)2.5FMEA Process Parameter Risk Assessment (106)2.6Classification of Process Parameters (108)2.7Process Excursion Studies (110)2.8Construction of the Design Space/Operating Space (110)2.9Cell Culture Process Control Strategy (110)3Case Study (111)3.1Construct CQA(s)Control Points Matrix (111)3.2Initial Process Parameter Risk Assessment (111)3.3Scale-Down Model (112)3.4Initial Process Characterization Experiments (112)3.5Final Process Characterization Experiment (115)3.6FMEA Process Parameter Risk Assessment (116)3.7Process Excursion Study (116)3.8Classification of Process Parameters (117)3.9Construction of Design Space (117)References (121)1IntroductionThe quality by design(QbD)concepts embodied in the International Conference on Harmonization(ICH)guidelines Q8(R2),Q9,Q10,and Q11have been applied to cell culture manufacturing process development and characterization[1–4].The January2011revised FDA Guidance for Industry,Process Validation:General Principles and Practices,integrates QbD principles into process validation prac-tices[5].These guidance documents outline the application of QbD principles in the lifecycle of a product from process design,process deﬁnition,and process characterization to process validation and continued process veriﬁcation.The expectation from regulatory agencies is that quality is designed or built into the product and its manufacturing process and quality cannot be adequately assured by testing[5].The beneﬁt of QbD is twofold:one is to provide a high level of assurance for product quality through lifecycle management of the product;the other is the potential forﬂexibility in the reporting responsibilities for movements within a registered design space[1].The implementation of QbD principles means product characteristics are designed and fully understood and their linkage to patient safety and clinical efﬁcacy is established,the interaction between critical product quality attributes and its manufacturing process are fully characterized,and control strategyDevelopment and Characterization of a Cell Culture Manufacturing Process95including design space is established to ensure that the manufacturing process is capable of consistently producing the product with the desired quality attributes [6,7].Figure1presents our approach in applying QbD principles to developing and characterizing a cell culture manufacturing process for establishing a process control strategy.Development of a cell culture manufacturing process control strategy starts from identifying drug substance critical quality attributes based on the quality target product proﬁle(QTTP).Critical quality attributes(CQAs)are identiﬁed through risk assessment that evaluates severity based on impact on patient safety and/or clinical efﬁcacy[8].The list of CQA(s)evolves during the development lifecycle.Then,a matrix is created to describe the interaction between critical quality attributes and process unit operations based on previous process development work,platform knowledge,literature information,andﬁrst principles.This control point matrix (CPM)visually indicates the origin,growth,reduction,or clearance of the quality attributes over the entire drug substance manufacturing process and demonstrates the process control points for each critical quality attribute.96 D.M.Marasco et al.Using the CPM as a guide,initial process parameter risk assessments are per-formed to evaluate the impact of process parameters and incoming raw materials systematically,within common cause variability,on critical product quality attributes.Process parameters are selected based on risk assessment for empirical evaluation using design of experiments(DOE)utilizing a qualiﬁed scale-down model.The purpose of the initial characterization study is to link process parameters to critical quality attributes.A resolution III or IV,fractional factional DOE is conducted depending on the number of parameters to be evaluated.Pro-cess parameters having statistically signiﬁcant impact on CQA(s)are selected for further study using response surface DOE.The functional relationships between these process parameters and CQA(s)are fully characterized.A secondary risk assessment,failure mode and effects analysis(FMEA),is performed during technology transfer to the commercial manufacturing site.Risks identiﬁed during the FMEA are further reduced or mitigated through process excursion and/or process challenge studies.Process parameters are classiﬁed as critical or noncritical postprocess charac-terization studies.The classiﬁcation is performed based on risk assessment and experimental results from process characterization studies.Based on risk assess-ments conducted throughout the development lifecycle,those process parameters assessed as not likely to affect CQAs are classiﬁed as noncritical.For process parameters evaluated in characterization studies,if a parameter is both statistically signiﬁcant and practically signiﬁcant in affecting CQA(s),it is classiﬁed as critical. Otherwise,it is classiﬁed as noncritical.A design space/operating space is constructed post parameter classiﬁcation.Per ICH Q8,design space is the multidimensional combination and interaction of input variables(e.g.,material attributes)and process parameters that have been dem-onstrated to provide assurance of quality.A cell culture process control strategy is established and documented based on information generated through risk assessments and process characterization studies during the development lifecycle.The establishment of analytical control strategy and microbiological control strategy is beyond the scope of this chapter.In the next sections,we describe our practices for process parameter risk assessments,CQA-driven process characterization by design of experiment,pro-cess parameter classiﬁcation,design space/operating space construction,and process control strategy establishment.2Development and Characterization of Cell Culture Manufacturing Process for Establishing a ProcessControl StrategyThe process development lifecycle consists of process design,process deﬁnition, process characterization,process validation,and continued process veriﬁcation.Development and Characterization of a Cell Culture Manufacturing Process97Table1Control points matrix describing the probable quality attribute control pointsCritical quality attribute Analytical method Unit operation inﬂuencing CQA(s)12345…N CQA#1OCQA#2OCQA#3O:XCQA#4O l X; CQA#5O X;O Origin of attribute at this unit operation:Growth of attribute at this unit operation;Reduction of attribute at this unit operationl Potential for growth or reduction of attribute at this unit operationX Signiﬁcant reduction/clearance of attribute at this unit operationAfter deﬁnition of an initial baseline process,characterization studies are initiated to understand fully the impact of process parameters and incoming raw material attributes,within common cause variability,on critical quality attributes.Process characterization starts with risk assessment.The intention of the initial risk assessment is systematically to evaluate the potential risk of process parameters and incoming raw material attributes from each unit operation,within common cause variability,on critical quality attributes.A cause and effect methodology is utilized in the initial risk assessment.2.1Construct CQA(s)Control Points MatrixPrior to initializing process characterization,sufﬁcient information should be available to describe,or reasonably estimate,the relationship between the unit operations and critical quality attributes.In order to facilitate the initial cause-and-effect risk assessment,a unit operation-based,control points matrix(CPM),is created to describe the probable control points(one or many)for each critical quality attribute.The matrix should include the most likely origin,growth, reduction,or clearance of the critical quality attributes across the entire drug substance manufacturing process.An example of a unit operation-based control point matrix is displayed in Table1.The control points matrix is used to guide the process parameter risk assessment by allowing unit operation characterization studies to focus only on the relevant critical quality attributes that are signiﬁcantly inﬂuenced by the purpose or design intent of the unit operation.The control points matrix is updated as additional information becomes available.2.2Initial Process Parameter Risk AssessmentInitial process parameter risk assessments are based on process knowledge,that is, a combination of practical experience and theoretical understanding.The process parameter risk assessment is performed iteratively throughout the development lifecycle to prioritize development efforts.Depending upon an organization’s experience and relative level of comfort conducting these risk assessments,they may be performed by a subject matter expert,or by a cross-functional team.Per ICH Q6,the degree of rigor and formality of quality risk management should reﬂect available knowledge and be commensurate with the complexity and/or criticality of the issue to be addressed.The initial process parameter risk assessment is performed in four basic steps: (1)identify output,(2)identify input process parameters,(3)evaluate the probablerisks,and(4)rank the process parameters by riskscore.The results from the risk assessment guide and prioritize the experimental program used to characterize each unit operation of the cell culture manufacturing process.2.2.1Identiﬁcation of OutputsCritical quality attributes are the main output analyzed in the initial process parameter risk assessment.Process performance indicators may also be considered.2.2.2Identiﬁcation of Input Process ParametersThe inputs,or process parameters,are identiﬁed based on the operational knowledge and mechanistic understanding of each unit operation in the manu-facturing process.A cause and effect diagram is a useful tool to organize and group process parameters systematically by function.The cause-and-effect diagram is constructed by placing the output(i.e.,product and process attributes of interest)at the right side of the diagram,with the potential design factors(i.e.,process parameters and incoming raw material attributes,e.g.,concentration accuracy)on a series of branches and subbranches extending from the output axis.The process parameters can be grouped by function or process step to ensure no process parameters are overlooked.98 D.M.Marasco et al.The level of branching can be moderated to facilitate efﬁcient communica-tion to ensure the level of detail is appropriate.An example cause-and-effect diagram describing a typical production bioreactor process is given in Fig.2[9].2.2.3Risk AnalysisAfter identifying the relevant process outputs (CQAs)and process inputs (process parameters)for each unit operation,the risks of common cause variability in the input parameters that may affect the output parameters are assessed.The risk analysis is based on ﬁrst principles,literature information,platform knowledge,manufacturing experience,scientiﬁc judgment of the subject matter experts,and molecule-speciﬁc empirical knowledge.The process parameters can be classiﬁed into two groups:those that have the potential to affect critical quality attributes and those that do not.Process parameters that do not have the potential to affect critical quality attributes may be assigned a low risk score.Typically,low-risk process parameters are not formally studied in laboratory models or designed experiments and are classiﬁedas Development and Characterization of a Cell Culture Manufacturing Process 99100 D.M.Marasco et al.noncritical with appropriate rationales.The remaining process parameters are classiﬁed as high risk,thus,they may have the potential to affect critical quality attributes and require additional evaluation to better understand,reduce,or miti-gate risks.The process parameter risk assessment follows the logic diagram pre-sented in Fig.3.The initial process parameter risk assessment is an integral part of the development of a control strategy;therefore,this assessment should be ade-quately documented.2.2.4Raw Material Risk AssessmentThe risks of variability inherent to the cell culture raw materials used to manu-facture drug substances on CQA(s)are evaluated in the development lifecycle.The raw material components are analyzed to assess the intrinsic risk(use of the correct raw materials)and the extrinsic risk(lot-to-lot variability)on CQA(s)and other quality attributes.The assessment includes the risks introduced from a quality,technical,and procurement perspective.The initial risk assessment occurs prior to the manufacture of pivotal clinical materials,and is reassessed as the process evolves.For example,technology transfer and/or changes in the process or supply chain may initiate a reassessment.The evaluation of raw material risk utilizes a series of weighted risk elements based on their criticality to the product or process,and the risk to the patient.Each raw material is assigned a three-tiered risk score(low=1,medium=3,or high=5)for each risk element using a combination of platform knowledge, manufacturing experience,opinions of the subject matter experts,and molecule-Development and Characterization of a Cell Culture Manufacturing Process101 speciﬁc empirical knowledge.The summation of the individual risk scores mul-tiplied by the risk element weight is calculated for each component.These values are used to rank the relative risks for each raw material component.As an example,the risk elements,and their respective weights,are described in table.Description of risk elementsWeight=5•Variability has the potential to affect the drug substance quality attributes•Ability of raw material to introduce bioburden,endotoxin,viral contaminates•Known issues with raw materialWeight=3•Molecular complexity•Potential to affect process performanceWeight=1•Experience with vendor•Manufactured for pharmaceutical industry2.3Risk Mitigation/Initial Process CharacterizationExperimentsFollowing the identiﬁcation of high-risk process parameters and raw materials,an experimental program is designed to characterize and mitigate the risks of iden-tiﬁed process parameters on critical quality attributes within common cause variability.2.3.1Experimental StrategyThe experimental program is designed to characterize the manufacturing process to ensure consistent robust manufacturing capability.The high-risk process parameters are studied in a series of designed experiments intended to understand and mitigate potential risks further.Scale-independent process parameters are explored using a laboratory scale-down model.Scale-dependent parameters may be studied using intermediate or at-scale bioreactors.The experimental program is typically initialized utilizing a highly leveraged design of experiments of a resolution sufﬁcient to identify the main effects and some quadratic effects.Depending upon the number of relevant process parameters identiﬁed in the risk assessment process,a single or a series of screening exper-iments can be planned.Multivariate fractional factorial design of experiments of resolution III or IV run using one or several blocks are common.Based on the output from the screening experiment,additional studies may be performed to102 D.M.Marasco et al. characterize parameters further that have a statistically and practically signiﬁcant effect on critical quality attributes.Prior to designing experiments,the high-risk process parameters should be examined while acknowledging that not all process parameters are independent of each other(i.e.,medium strength and medium osmolality).Potential correlations should be identiﬁed and taken into consideration.2.3.2Process Parameter Range of InterestDuring cell culture manufacturing process characterization studies,the target setpoints of process parameters are determined based on process design and def-inition experimentation;process parameter ranges selected are intended to eval-uate the impact of common cause variability in operations on critical quality mon cause variability is deﬁned as the expected level of variability experienced during normal unit operations in a manufacturing environment when executed according to the batch record instructions.The range of interest is determined from the current understanding of the at-scale control capability using a combination of operational variability,or the variance from target setpoints,and the measurement uncertainty of the device(s) that record the process measurement.Theoperationalvariabilityisameasureofperformancederived fromsampling unit operations in the clinical manufacturing or commercial manufacturing facilities.The range encompassing common cause variability is chosen so that the probability of the parameter values being within the range of the target setpoints±operational vari-ability is at least0.995(or99.5%).Generally,six times the operational variability is selectedtoensurethatthevaluesofagivenprocessparameterwillfallwithinthisrange irrespective of the underlying distribution[10].The measurement uncertainty characterizes the dispersion of the values that could be reasonably attributed to the measurement.The measurement uncertainty is designed to reduce the false acceptance rate and is selected to ensure95%of the recorded measurements fall within the desired range.The measurement uncer-tainty is derived from either the measurement system design speciﬁcation or historic calibration performance[11].The summation of operational variability(containing99.5%of the observed values)and measurement uncertainty(containing95%of the recorded measure-ments)deﬁnes the recommended minimum range of interest used to characterize the process,as displayed in Fig.4.2.3.3Laboratory Scale Models for Process CharacterizationIn most scenarios,performing process characterization studies at the manufac-turing scale is not practically feasible due to the cost of operation,and limited availability of large-scale bioreactors.Therefore,laboratory scale models are usedto perform process characterization experiments that deﬁne acceptable process ranges and establish predictive relationships between the scale-independent pro-cess parameters and critical product quality attributes.This approach is in align-ment with ICH guidance [4];small–scale models can be developed and used to support process development studies.The development of a model should account for scale effects and be representative of the proposed commercial process.A scientiﬁcally justiﬁed model can enable a prediction of product quality,and can be used to support the extrapolation of operating conditions across multiple scales and equipment.The cell culture manufacturing process includes a series of shake ﬂasks and conventional stirred-tank or disposable bioreactors to manufacture the unprocessed bulk drug substance.The culture expansion steps have a limited potential for impact on critical quality attributes due to negligible accumulation of product;therefore the focus of the scale-down model is typically on the production bio-reactor unit operation.The bioreactor conﬁguration has ﬁve primary control loops intended to measure and control culture temperature,dissolved oxygen,culture pH,agitation rate,and vessel pressure by manipulating caustic and acidic pH control loops,air,oxygen,and carbon dioxide gas ﬂow rates,vessel jacket heat exchanger,and the agitator drive.An example P&ID (piping and instrumentation diagram)is provided in Fig.5.The cell culture process parameters can be separated into two groups including scale-dependent and scale-independent parameters.The operating conditions for scale-independent parameters (i.e.,temperature,pH,dissolved oxygen concen-tration)are conserved across different scales.The scale-dependent parameters (i.e.,agitation rate,gas ﬂow rates,nutrient addition volume)are adjusted to conform to the scaling strategy employed.The scale-dependent parameters included in a bioreactor system are driven by gas–liquid and liquid–liquid mixing with the associated mass and heat transport phenomena.Mixing systems do not scale proportionally in all dimensions;therefore a basis for scaling up mixing unit operations must be chosen by bal-ancing the characteristics that are important to the process under consideration.Scaling strategies are typically based on a combination of geometric similarity,kinematic similarity,dynamic similarity,and/or power per unit volume input.TargetVariability6σr 2σmu2σmu 6σrTypically two of the four methods are selected,allowing the other characteristics to change.Bioreactor unit operations used for mammalian cell culture processes are usually scaled up by conserving the power per unit volume with geometrically similar vessels.When scaling up on the basis of geometric similarity and constant power per unit volume,the relative agitator tip speed and the bulk mixing time increase.Increasing the agitator tip speed may increase the risk of shear damage to the cells;however,prior experiments have demonstrated that the risk of damage is minimal over the normal operating range of interest.Increasing the bulk mixing time will result in an increased risk of vessel heterogeneity which could affect the product’s critical quality attributes and process performance.Equipment design and addi-tional experiments should be considered if there is a high risk of vessel hetero-geneity affecting culture performance or critical quality attributes.In cell culture processes the proper scaling of gas ﬂow rates to control dissolved carbon dioxide and dissolved oxygen levels is not trivial.As the process is scaled up,the mass transport of oxygen increases with vessel volume leading to a decreased volumetric ﬂow rate of oxygen necessary to meet the culture demand.The resulting decrease in volumetric ﬂow rate reduces the capability to remove carbon dioxide.An air balance is required in the sparger line to provide a sufﬁcient volumetric ﬂow for carbon dioxide removal.In addition,the medium chemistry and the proﬁle of metabolic by-products (i.e.,lactate concentration)may lead to a feedforward control strategy based on the interaction between dissolvedoxygen Fig.5Example bioreactor piping and instrumentation diagramand pH control loops.In our system,the gas sparger conﬁguration may be spec-iﬁed so that the amount of gasﬂow needed to maintain the dissolved oxygen control is the amount of gas needed for carbon dioxide removal.The carbon dioxide management in the at-scale and intermediate-scale bioreactors may be determined through process models that simultaneously solve the chemistry equilibrium and mass transfer equations through the course of the run assuming that the oxygen uptake rate and signiﬁcant metabolic by-products are deﬁned by the process conditions.The models are used to deﬁne a target airﬂow rate that allows for carbon dioxide off-gassing.The interaction between multiple scale-dependent control loops presents additional challenges when scaling down cell culture processes to the laboratory bench scale.The power per unit volume is difﬁcult to determine as the standard vessel geometry is modiﬁed to accommodate the reduced scale.In addition,the ratio between culture volume and surface area in contact with the head space increases,inﬂuencing the mass transfer rates for gases.As a result controlling the pCO2concentration at the laboratory scale is difﬁcult to model.Additional experiments may be performed to understand the risks better that elevated carbon dioxide levels have on culture performance and/or product critical quality attributes.The capabilities of the laboratory scale models are monitored throughout the development lifecycle and the risk,whether the scale-down models are repre-sentative of at-scale processes,is analyzed as sufﬁcient large-scale information becomes available.The laboratory-scale models are analyzed by comparing results between the scale-down and at-scale processes for outcomes including critical quality attributes,other product quality attributes,and process performance indicators.The scale comparison data for quality attributes are explored using statistical methods.The data from bioreactors run at process targets in the scale-down model (from process characterization and process design and deﬁnition studies)are compared to the data generated from at-scale clinical material manufacturing campaigns.An equivalence test(two-one-sided t test,TOST)with a predeﬁned practical difference is used to test for equivalency between critical and other product quality attributes[12].A practical difference threshold should be sufﬁcient to support the claims,or intended use of the scale-down model.Based on these criteria,the suitability of the scale-down model relative to the at-scale process can be assessed.The process performance indicators are also explored qualitatively by exam-ining the process trends over parisons are made relative to the direc-tionality and closeness of the time-series data.If the performance of the scale-down model is not equivalent,additional analysis should be performed to determine if the process characterization results are sufﬁcient to construct an adequate control strategy.If not,additional work should be performed to develop a better model,or generate additional data to mitigate risks.。

高纯气体、工业气体、电子气体、标准气体相关国家标准清单

高纯气体、工业气体、电子气体、标准气体相关国家标准清单以下是各类高纯气体、工业气体、标准气体等气体的国家标准，具体应用问题可查看氦 H eGB⁄T 4844-2011 纯氦、高纯氦和超纯氦 GB⁄T 16943-2009 电子工业用气体氦 GB⁄T 28123-2011 工业氦氢 H 2GB⁄T 3634.2-2011氢气第二部分：纯氢、高纯氢和超纯氢 GB⁄T 3634.1-2006 氢气第1部分：工业氢 GB⁄T 16942-2009 电子工业用气体氢GB 31633-2014 食品安全国家标准食品添加剂氢气氮 N 2GB⁄T 8979-2008 纯氮、高纯氮和超纯氮 GB⁄T 16944-2009 电子工业用气体氮 GB⁄T 3864-2008 工业氮GB 29202-2012 食品安全国家标准食品添加剂氮气氩 ArGB⁄T 4842-2017 氩GB⁄T 16945-2009电子工业用气体氩氧 O 2GB⁄T 14599-2008.纯氧、高纯氧和超纯氧 GB⁄T 3863-2008 工业氧GB⁄T 8982-2009 医用及航空呼吸用氧空气 Air低氧氮混合气（O 2 4.5% + N 2 95.5%）高纯空气由高纯氮气与高纯氧气合成N2(79~80%)+O2(20-21%) (非天然空气) GB⁄T 34526-2017 混合气体气瓶充装规定GB⁄T 5274-2018 气体分析——校准用混合气体的制备第1部分：称量法制备一级混合气体乙炔 C 2H 2 GB 6819-2004 溶解乙炔六氟化硫 SF 6GB⁄T 12022-2014工业六氟化硫GB⁄T 18867-2014 电子工业用气体六氟化硫二氧化碳 CO 2GB⁄T 23938-2009 高纯二氧化碳 GB⁄T 6052-2011 工业液体二氧化碳GB 1886.228-2016 食品安全国家标准食品添加剂二氧化碳甲烷 CH 4 GB⁄T 33102-2016 纯甲烷和高纯甲烷氧化亚氮 N 2O GB⁄T 28729-2012 氧化亚氮一氧化碳 CO 一氧化碳混合气（CO 2% + N 2 98%）（CO 10% + N 2 90%）用于紧急终止剂和阻聚剂GB⁄T 35995-2018 一氧化碳GB⁄T 34526-2017 混合气体气瓶充装规定GB⁄T 5274.1-2018 气体分析——校准用混合气体的制备第1部分：称量法制备一级混合气体丙烷、丁烷、丙丁烷HG⁄T 3661.2-2016 工业燃气切割焊接用丙烷 SH 0553-1993 工业丙烷、丁烷 GB 11174-2011 液化石油气GB⁄T 19465-2004 工业用异丁烷 (HC-600a) GB⁄T 22026-2008 气雾剂级丙烷(A-108) GB⁄T 22025-2008 气雾剂级异丁烷(A-31) GB⁄T 22024-2008 气雾剂级正丁烷(A-17) 丙烯HG⁄T 3661.1-1999 焊接切割用燃气丙烯 GB⁄T 7716-2014 聚合级丙烯GB⁄T 33774-2017 电子工业用气体丙烯液氨GB⁄T 536-2017 液体无水氨氟利昂GB⁄T 7778-2017 制冷剂编号方法和安全性分类GB⁄T 7371-1987 工业用一氟三氯甲烷(F11)GB⁄T 7372-1987 工业用二氟二氯甲烷(F12)GB⁄T 7373-2006 工业用二氟一氯甲烷（HCFC-22）GB⁄T 18826-2016 工业用1,1,1,2-四氟乙烷（HFC-134a）GB⁄T19602-2004 工业用1,1-二氟乙烷(HFC-152a)GB⁄T 18827-2002 工业用1,1--二氯--1--氟乙烷(HCFC-141b) HG⁄T 5161-2017 混合制冷剂R404系列HG⁄T 5162-2017 混合制冷剂R410系列工业混合气体HG⁄T 3728-2004 焊接用混合气体氩-二氧化碳HG⁄T 4983-2016 工业燃气丙烷⁄天然气混合气HG⁄T 4984-2016 焊接用混合气体二氧化碳-氧⁄氩HG⁄T 4985-2016 焊接用混合气体氦⁄氩HG⁄T 4986-2016 焊接用混合气体氧⁄氩电子工业气体GB⁄T 34085-2017 电子工业用气体三氟甲烷GB⁄T 34091-2017 电子工业用气体六氟乙烷GB⁄T 33774-2017 电子工业用气体丙烯GB⁄T 15909-2017 电子工业用气体硅烷GB⁄T 32386-2015 电子工业用气体六氟化钨GB⁄T 31986-2015 电子工业用气体八氟丙烷GB⁄T 31987-2015 电子工业用气体锗烷GB⁄T 14602-2014 电子工业用气体氯化氢GB⁄T 18867-2014 电子工业用气体六氟化硫GB⁄T 18994-2014 电子工业用气体高纯氯GB⁄T 31058-2014 电子工业用气体四氟化硅GB⁄T 17874-2010 电子工业用气体三氯化硼GB⁄T 26249-2010 电子工业用气体硒化氢GB⁄T 26250-2010 电子工业用气体砷化氢GB⁄T 14600-2009 电子工业用气体氧化亚氮GB⁄T 14601-2009 电子工业用气体氨GB⁄T 14603-2009 电子工业用气体三氟化硼GB⁄T 14604-2009 电子工业用气体氧GB⁄T 14851-2009 电子工业用气体磷化氢GB⁄T 16942-2009 电子工业用气体氢GB⁄T 16943-2009 电子工业用气体氦GB⁄T 16944-2009 电子工业用气体氮GB⁄T 16945-2009 电子工业用气体氩GB⁄T 21287-2007 电子工业用气体三氟化氮标准气体产品标准制备与分析GBT 5274.1-2018 气体分析——校准用混合气体的制备第1部分：称量法制备一级混合气体ISO 6142-1:2015 Gas analysis -- Preparation of calibration gasmixtures -- Part 1: Gravimetric method for Class I mixturesGB⁄T 10248-2005 气体分析校准用混合气体的制备静态体积法ISO 6144:2003 Gas analysis -- Preparation of calibration gasmixtures -- Static volumetric methodGB⁄T 5275-2014 气体分析动态体积法制备校准用混合气体ISO 6145-(2003~2017) Gas analysis -- Preparation ofcalibration gas mixtures using dynamic methods (Part1~11)***GB⁄T 10628-2008 气体分析——校准混合气组成的测定和校验比较法ISO 6143:2001 Gas analysis -- Comparison methods fordetermining and checking the composition of calibration gasmixturesGB⁄T 35530-2017 混合气体称量制备组分相关性控制ISO⁄TS 29041-2008 Gas mixtures -- Gravimetric preparation--Mastering correlations in compositionGB⁄T 34710.1-2017混合气体的分类第1部分：毒性分类GB⁄T 34710.2-2018混合气体的分类第2部分：腐蚀性分类GB⁄T 34710.3-2018混合气体的分类第3部分：可燃性分类ISO 10298-2018 Gas cylinders -- Gases and gas mixturesDetermination of toxicity for the selection of cylinder valveoutletsISO 13338-2017 Gas cylinders -- Gases and gas mixtures --Determination of tissue corrosiveness for the selection ofcylinder valve outletsISO 13338-2017 Gas cylinders -- Gases and gas mixtures --Determination of tissue corrosiveness for the selection ofcylinder valve outlets标准物质证书CNAS-GL010:2018 标准物质⁄标准样品证书和标签的内容ISO Guide 31:2015 Reference materials -- Contents ofcertificates, labels and accompanying documentationGB⁄T 15000.4-2003 标准样品工作导则(4) 标准样品证书和标签的内容***JJF 1186-2018 标准物质证书和标签要求GB⁄T 35860-2018 气体分析——校准用混合气体证书内容ISO 6141:2015 Gas analysis — Contents of certificates forcalibration gas mixtures标准物质使用CNAS-GL004：2018 标准物质⁄标准样品的使用指南ISO Guide 33:2015 Reference materials -- Good practice inusing reference materialsJJF 1507-2015 标准物质的选择与应用技术***GB⁄T 15000.8-2003 标准样品工作导则(8) 有证标准样品的使用***GB⁄T 35861-2018 气体分析校准用混合气体使用过程中的一般质量保证指南ISO⁄TS 14167:2003 Gas analysis -- General quality assuranceaspects in the use of calibration gas mixtures - Guidelines标准物质生产能力CNAS-GL017:2018 标准物质标准样品定值的一般原则和统计方法***ISO Guide 35:2017 Reference materials -- Guidance forcharacterization and assessment of homogeneity andstability***GB⁄T 15000.3-2008 标准样品工作导则(3)标准样品定值的一般原则和统计方法***JJF 1343-2012 标准物质定值的通用原则及统计学原理***CNAS-CL01:2018 检测和校准实验室能力认可准则GB⁄T 27025-2008 检测和校准实验室能力的通用要求***ISO⁄IEC 17025:2017 General requirements for the competenceof testing and calibration laboratoriesCNAS-CL04:2017 标准物质⁄标准样品生产者能力认可准则***GB⁄T 15000.7-2012 标准样品工作导则(7) 标准样品生产者能力的通用要求***JJF 1342-2012 标准物质研制（生产）机构通用技术要求***ISO 17034:2016 General requirements for the competence ofreference material producers其他JJF 1001-2011 通用计量术语及定义ISO⁄IEC Guide 99:2007 International vocabulary of metrology --Basic and general concepts and associated (VIM)JJF 1059.1-2012 测量不确定度评定与表示GB⁄T 27418-2017 测量不确定度评定和表示ISO⁄IEC CD Guide 98-3 valuation of measurement data -- Part3: Guide to uncertainty in measurement (GUM)JJF 1005-2016 标准物质通用术语和定义JJG 1006-1994 国家一级标准物质ISO Guide 30:2015 Reference materials -- Selected terms and definitions气瓶标准相关基本准则TSG R0006-2014 气瓶安全技术监察规程GB∕T 16163-2012 瓶装气体分类GB∕T 7144-2016 气瓶颜色标志GB∕T 16804-2011 气瓶警示标签气瓶制造GB 5099-1994 钢质无缝气瓶GB∕T 5099.1-2017 钢质无缝气瓶第1部分：淬火后回火处理的抗拉强度小于1 100MPa的钢瓶***GB∕T 5099.3-2017 钢质无缝气瓶第3部分：正火处理的钢瓶***GB∕T 5099.4-2017 钢质无缝气瓶第4部分：不锈钢无缝气瓶****** GB∕T 5099.1,3,4-2017 部分代替G B 5099-1994GB∕T 28054-2011 钢质无缝气瓶集束装置GB∕T 11640-2011 铝合金无缝气瓶GB∕T 5100-2011 钢质焊接气瓶GB∕T 24159-2009 焊接绝热气瓶GB∕T 11638-2011 溶解乙炔气瓶GB∕T 17268-2009 工业用非重复充装焊接钢瓶气瓶检验GB∕T 12135-2016 气瓶检验机构技术条件GB∕T 13004-2016 钢质无缝气瓶定期检验与评定GB∕T 13077-2004 铝合金无缝气瓶定期检验与评定GB∕T 13075-2016 钢质焊接气瓶定期检验与评定GB∕T 34347-2017 低温绝热气瓶定期检验与评定GB∕T 13076-2009 溶解乙炔气瓶定期检验与评定气瓶充装GB∕T 27550-2011 气瓶充装站安全技术条件GB∕T 14194-2017 压缩气体气瓶充装规定GB∕T 34526-2017 混合气体气瓶充装规定GB∕T 34528-2017 气瓶集束装置充装规定GB∕T 14193-2009 液化气体气瓶充装规定GB∕T 28051-2011 焊接绝热气瓶充装规定GB∕T 13591-2009 溶解乙炔气瓶充装规定GB∕T 28052-2011 非重复充装焊接钢瓶充装规定GB∕T 34525-2017 气瓶搬运、装卸、储存和使用安全规定GB∕T 30685-2014 气瓶直立道路运输技术要求GB∕T 15382-2009 气瓶阀通用技术要求GB∕T 15383-2011 气瓶阀出气口连接型式和尺寸GB 15383-2011 气瓶阀出气口连接型式和尺寸GB∕T 7899-2006 焊接、切割及类似工艺用气瓶减压器GB∕T 25473-2010 焊接、切割及类似工艺用管路减压器GB 26787-2011 焊接、切割及类似工艺用管路减压器安全规范JJF 1328-2011 带弹簧管压力表的气体减压器校准规范GB∕T 8335-2011 气瓶专用螺纹GB∕T 14791-2013 螺纹术语GB∕T 12716-2002 60°密封管螺纹GB∕T 7307-2001 55°非密封管螺纹GB∕T 7306 55°密封管螺纹消防用气体相关GB 20128-2006 惰性气体灭火剂GB 4396-2005 二氧化碳灭火剂GB 35373-2017 氢氟烃类灭火剂GB 18614-2002 七氟丙烷（HFC227ea）灭火剂GB 25971-2010 六氟丙烷（HFC236fa）灭火剂GA 1203-2014 气体灭火系统灭火剂充装规定GB 16669-2010 二氧化碳灭火系统及部件通用技术类型GB 25972-2010 气体灭火系统及部件GB⁄T 20702-2006 气体灭火剂灭火性能测试方法GB⁄T 795-2008 卤代烷灭火系统及零部件MT⁄T 701-1997 煤矿用氮气防灭火技术规范GB 16670-2006 柜式气体灭火装置GB⁄T 5907.5-2015 消防词汇第5部分：消防产品DB33⁄1011-2003 IG541混合气体灭火系统设计、施工、验收规范DB61⁄296-2002 洁净气体IG541灭火系统设计、施工、验收规范DG⁄TJ08-306-2001 惰性气体IG-541灭火系统技术规程。

conversationanalysis

Complementary Therapies in Medicine(2004)12,131—135Conversation analysisJohn Chatwin∗School of Healthcare Studies,University of Leeds,Leeds LS29UT,UKKEYWORDS Conversation analysis; CAM interactions; Medical encounters; Socio-linguistics Summary Conversation analysis(CA)is well established as a means of exploring the interactional detail of conventional healthcare encounters.It is also becoming increasingly popular in action to CAM.This article outlines the main features of CA,how it can be used in a CAM context,and the type of information it can be expected to reveal.Examples of original CA data obtained from CAM consultations are presented to illustrate the CA method.©2004Elsevier Ltd.All rights reserved.CA—–what is it?Conversation analysis(CA)is a socio-linguistic ap-proach that is largely concerned with the analysis of the verbal communication that people routinely use when they interact with one another.It origi-nated in the1960’s,primarily due to the work of the American sociologist Harvey Sacks,1and draws on ethnomethodological and interactional traditions of naturalistic observation.Essentially,CA provides an analytical method that can be used to expose the underlying structural‘rules’that govern how day-to-day activities are composed and organised.2What can CA tell us about CAM?In terms of CAM,an obvious application for CA is as a tool for examining the interactions that occur between patients and practitioners.There is a long tradition of CA research in theﬁeld of conventional medicine(see,for example:3—6).Over the last few*T el.:+441132331374;fax:+441132331204.E-mail address:******************.uk.years the increasing integration of CAM into main-stream medicine has encouraged some researchers to focus on this arena too—–so far concentrating mostly on talk-based therapies such as counselling and homoeopathy(see,for example:7).How would you use it?T o be used effectively,CA depends on analysing a large number of naturally occurring examples of a given phenomena.In CAM,for example,youmight be interested in studying one particular aspect of behaviour,such as how practitioners open their consultations,how patients present descriptions of their symptoms,or how treatment decisions are negotiated.Material for analysis using CA is routinely collected in the form of video or audio recordings.These‘raw’data are then transcribed using a detailed system of notation(see Fig.2) that attempts to capture,among other things,the relative timing of participants’utterances(the ex-act points,for example,when one person’s speech overlaps another in their ongoing talk),nuances of sound production,word emphasis,and certain aspects of intonation.CA contrasts with other qual-0965-2299/$—see front matter©2004Elsevier Ltd.All rights reserved. doi:10.1016/j.ctim.2004.07.042132J.Chatwinitative research methods,such as interviewing or observational work,in that(at the data collection and processing phase at least)the process does not rely to any great extent on subjective interpreta-tion.CA in fact represents a signiﬁcant departure from other linguistically oriented approaches be-cause utterances are not seen primarily in relation to linguistic structure(i.e.in terms of their sense and meaning),but rather as objects utilised in the ongoing negotiation of social tasks—–requests, greetings,proposals,complaints and so on—–and as such,their relative positioning within sequences of interaction can be accurately mapped. Another useful feature of the method is that it allows for the systematic analysis of comparatively large sets of data,which,as an aim of CA is to detect commonalties of behaviour,helps to reduce any distortions that might be introduced by the id-iosyncratic communication styles of individuals.How to go about using CAAssuming the phenomena or interactional environ-ment youwant to analyse is compatible with the CA approach,the procedure would be:1.Identify what it is you want to study:Is it aspeciﬁc type of activity or behaviour?Or is it something broader?Youmay simply have a no-tion that a particular interactional activity cre-ates a certain‘feel’or atmosphere,and wish to isolate the behavioural elements that are contributing to this.In CAM and other medi-cal settings,CA has been used to explore ar-eas such as the way patients contextualise their symptoms,8how they describe what is wrong with them,9and how they seek information.10 Attempts have also been made to identify what it is in the interactions between therapists and patients that gives certain CAM encounters their collegial quality.112.Collect your data:The material youcollect willbe subjected to a detailed transcription process, so high quality video or audio recordings are es-sential.Similarly CA deals with real interaction.Mocked-up,role-played or staged exchanges will not do—–unless of course it is the idiosyncrasies of behaviour within these particular arenas that you wish to study.For best results,you will need to collect as many examples as possible of the behaviour you are interested in.So for example, if you are exploring the way in which acupunc-turists organise their talk when referring to the u se of needles(as youmight be if youwere try-ing toﬁnd practical ways of making things eas-ier for patients who were scared of needles)you would concentrate on obtaining as many natural recordings of this activity occurring as you could.Not just from one practitioner or a single setting, but from a whole range of different acupunctur-ists with different patients.For their CA based study focusing on allopathic doctor—patient in-teraction,Heritage and Strivers3recorded335 consultations involving19doctors,and data col-lections of this size are not uncommon in CA.Essentially the greater the number of examples, the less likelihood that analytical distortions will be introduced due to the idiosyncratic charac-teristics of individual participants.3.Transcribe your data:This can be the most timeconsuming part of the process but is at the heart of the method.CA transcription needs to be extremely detailed,accurate and consistent, and is a difﬁcult skill to master.As a rough guide,an efﬁcient transcriber(often the re-searcher who records the original material)may be able to transcribe about1min of a recording in1h,depending on the complexity of the talk.Multi-party and lively or argumentative interactions where there is a lot of overlap-ping speech can take far longer to unravel.There are,unfortunately,no speciﬁc software packages that can come anywhere near the consistency required to do this automatically, but at an academic level,the intense process of manual transcription can be an important part of the analytical process,allowing a researcher to really get inside the data.Some digital recording and editing packages such as N-track or sound forge can make the process easier, however,allowing recordings to be displayed on-screen and controlled alongside your word processor(see Fig.1).These kinds of software can make the categorisation and comparison of data much easier at the analytical stage too.4.Analysis:Normally,in‘pure’CA,once youhave assembled a sufﬁciently large collection of recording transcripts,youwill isolate data relating to the particular discrete activities that are of interest(say,‘greetings’or‘topic initia-tion’)and arranged them into collections.You can then methodically analyse them to reveal underlying sequential commonalities and pat-terns.CA may,however,also be used in a much broader way to work with smaller pieces of data(a transcript of a single complete CAM consulta-tion,for example).This approach is likely to be of most interest to researchers without a pure CA background,or for studies in which CA is not the primary methodology.A traditional way of approaching the initial stages of CA is for a groupConversation analysis133Figure1.The simultaneous display of the digital recording package‘N-track’,and MS Word in different screen windows. Some software packages not speciﬁcally designed to work with CA can be very useful during transcription and analysis.of analysts to get together and hold a‘data ses-sion’in which examples of a single transcript or short collections of material are brainstormed.This process can be an extremely useful way of isolating original and tangential themes.Data exampleThe two short transcript extracts below will give a very basic illustration of the way in which CA data is presented and analysed.In keeping with the CAM context,both are taken from towards the end of ho-moeopathic consultations and represent the point where the homoeopaths are initiating the activity of offering treatment(indicated by the highlighted area).The short table in Fig.2gives the meanings of the symbols used,but note particularly the way in which each individual’s‘turn’at talk begins on a separate line,with the points at which speech over-laps indicated by square brackets(at lines2and3 in Scheme1,and11and12in Scheme2).Pauses (given in tenths of a second)between and within turns are indicated by the numbers in parenthesis.Intonationally stressed words are underlined,while words in capital letters are louder in relation to the surrounding speech.At an analytical level,youcan see that the transcription method has effectively captured two contrasting ways in which the homoeopaths organise their treatment giving‘turn’at talk(the concept of turn-taking being a fundamental tenet of CA)as well as illustrating the different sequen-tial outcomes(in terms of patient responses)which result from these.In Scheme1the homoeopath uses an approach which is overtly‘non-directive’—–she doesn’t actually suggest a treatment option as such,but in fact asks the patient to take control of the treatment process:‘...what are youthinking you-might do....’(line9).Similarly,her delivery at this point is fractured,with frequent pauses and hesitations,which further help to give it a non-directiveﬂavour.In contrast,the way in which the homoeopath in Scheme2switches into treatment giving is highly directive and focused. She displays no hesitation,and succinctly partitions off her treatment delivery from her preceding talk with a‘RIGHT’which is both louder relative to the134J.ChatwinFigure2.Scheme1.Scheme 2.surrounding speech,and delivered with a degree of emphasis.She follows with ‘...I’m going to give youmalandrinu m today ....’(lines 8—9)which is both directive and categorical.The sequential effect of the two different ap-proaches is also traceable in the transcript.In Scheme 1,the homoeopath’s ‘open’framing of her treatment turn allows the patient to offer her own suggestion;in Scheme 2the categorical or ‘closed’delivery that the homoeopath utilises allows little interactional opportunity for the patient to do any-thing other than go along with her .T aken as pure CA,these two short extracts could not be used to provide any deﬁnitive cate-gorisations (in this case relating to the ways that treatment decisions are delivered).A far more extensive collection would be required before any speciﬁc conclusions about reoccurring routines of interaction could be drawn.In terms of wider social research,however ,even a small numberConversation analysis135of contrasting data fragments like this can be useful.These particular data,for example,came from a multi-disciplinary study looking at ways to improve patient participation in treatment decision making,1and it can be seen that the kind of micro-level detail that CA delivers can readily provide an empirical grounding for obser-vations and concepts developed using other,more subjective,qualitative approaches.ResourcesRecommended readingA good basic introduction to the CA method is: Conversation Analysis by Ian Hutchby and Robin Woofﬁtt.12But the absolute bible of CA is a col-lection of lecture transcripts by its inventor Har-vey Sacks,who died in James Dean style in the mid 1970’s.Lectures in Conversation(edited by Gail Jefferson)is published in two volumes by Blackwell.SoftwareDigital recording and editing software can make the task of transcription and analysis easier,allowing youto slow down recordings,make accu rate inter-val timings(traditionally done with a stopwatch),or remove a certain amount of noise from bad record-ings.T wo software packages that have been found very useful for CA work are:N-track:Which allows for the simultaneous dis-play of several tracks of audio on your computer at the same time and is good for archiving audio and comparative analytical work.Available over the in-ternet from:.Sound forge:Which is an industry standard audio editing package that,although quite ex-pensive,is extremely useful for cleaning up bad1Data collected for the Department of Health funded PaPaYA project(Patient Participation in York and Aberdeen).Reference number3700514.recordings and creating professional sounding au-dio clips for presentations etc.Available from: .References1.Sacks H.In:Jefferson G,editor.Lectures in conversation,Vols1and2.Oxford:Blackwell;1998.2.Per¨a kyla A.Conversation analysis:a new model of re-search in doctor—patient communication.J R Soc Med 1997;90:205—8.3.Heritage J,Stivers T.Online commentary in acute medicalvisits:a method of shaping patient expectations.Soc Sci Med1999;49:501—1517.4.Heath C.The delivery and reception of diagnosis in thegeneral-practice consultation.In:Drew P,Heritage J,ed-itors.T alk at work:interaction in institutional settings.Cambridge:Cambridge University Press;1995.5.Frankel RM,West C.Miscommunication in medicine.In:Coupland N,Giles H,Wiemann JM,editors.Miscommuni-cation and problematic talk.London:Sage;1991.6.West C.Ask me no questions....An analysis of queries andreplies in physician—patient dialogues.In:Fisher S,Dun-das T,editors.The social organisation of doctor—patient communication.Washington:The Centre for Applied Lin-guistics;1983.7.Per¨a kyla A.Aids counselling.Institutional interaction andclinical practice.Cambridge:Cambridge University Press;1995.8.Gill VT.Doing attributions in medical interaction:patients’explanations for illness and doctors’responses.Social Psy-chology Quarterly1988;61:260—342.9.Ruusuvuori J.Control in the medical consultation:prac-tices of giving and receiving the reason for the visit in pri-mary health care.Unpublished doctoral dissertation.Uni-versity of T ampere;2000.10.Heritage J,SeﬁS.Dilemmas of advice:aspects of the deliv-ery and reception of advice in interactions between health visitors andﬁrst time mothers.In:Drew P,Heritage J,edi-tors.T alk at work.Cambridge:Cambridge University Press;1992.11.Chatwin munication in the homoeopathic therapeu-tic encounter.Unpublished PhD thesis.York:York Univer-sity;2003.12.Hutchby I,Woofﬁtt R.Conversation analysis:principles,practices and applications.Cambridge:Polity;2001.。

Preparation and Characterization of Component Materials for Intermediate Temperature Solid Oxide

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Novel Strategies for Preparation and Characterization of Functional Polymer-metal Nanocomposites

A r ticle ID:042727104(2007)0520630202R 22B y D N M ,,2D M @N ovel Strategies for Preparation and Character izationof Functional Polymer 2metal N anocomposites f orElectr ochemical ApplicationsD.N.Muravie v(Depa rt ment of Chemist ry ,Autonomous U niv ersity of Ba rcelona ,08193Bellater ra ,Ba rcelona ,Spain)K eyw o r ds :n ov el strategies;polymer 2metal ;nan ocompositesCLC number :O 636.9 1　IntroductionThe synt hesi s and charact erization of Metal Nano Part icles (MN Ps)has at tracted great i nterest of scien 2ti st s and technologist s wit hi n t he last years due t heir unique physical and chemical properties ,which substan 2tially differ f rom t hose of bot h bul k material and si ngle atoms.These properties provide various pract ical appli 2cations of MNPs i ncluding cat alysi s 2and elect rocatalysi s 2based processes ,which occur in ,for example ,f uel cells of different types or in various sensing devices (e.g.amperomet ric sensors and biosensors ).The main draw 2back ,which still li mit s t heir wide applicat ions ,is i nsufficient stabilit y of MN Ps deali ng wit h t hei r high t rend to aggregate.Coalescence of MNPs result s in t he loss of t heir nanomet ric size and s pecial properties.St abilization of MNPs i n polymeric mat rices of different t ypes has been proven to be one of t he most promi sing strategies to prevent t hei r aggregat ion and to save t hei r properties [1].The Polymer 2Stabilized MNPs (PSMN Ps )and t he polymer 2metal nanocomposite materials on t heir base start to fi nd wide applications in various fields of science and technology.2　ResultsIn t his com munication we demonst rat e t hat Metal 2Polymer Nanocomposite Membranes (MPNCMs )con 2t aining MN Ps can be easily prepared in a Sulfonat ed PolyEt herEt her K etone (SP EE K )polymeric mat ri x by using t he polymeric membranes as nanoreactors to bot h synthesize and to characterize t he composition and ar 2chi tect ure of t he formed MN Ps [2-3].Metal ions (or met al ion c omplexes )are fi rst i nc orporated in the poly 2meric matrix where t hey undergo a reduct ion reaction t hat leads to t he formation of corresponding MPNCMs.Since t his t echnique allows for carrying out successive met al loading 2reduction cycles ,it permit s to synt hesize bot h monometallic and bi metallic (e.g.,core 2shell )MNPs.The proposed approach i s illust rated by t he resul ts obt ained by t he synt hesi s and characterization of MPNCMs containing Pt ,Pd (monometallic )and Pt @Cu and Pd @Cu (core 2shell )PSMN Ps along wit h t hei r application i n electrochemical sensor and biosens or const ruc 2tions.第46卷　第5期2007年10月复旦学报(自然科学版)Journal of Fudan U niversity (Natural Science )Vol.46No.5Oct.2007eceived da te :20070704iogra ph :..uraviev Corres ponde nce author E mail :imit ri.uraviev ua b.es.References:[1]　A D Pomogailo,G I Dzhardimalieva,A S Rozenberg,et al.K inetics a nd mechanism of in situ simultaneous forma2tion of metal nan oparticles in stabilizing polymer Matrix[J].J Na nopar ticle Res,2003,5:4972519.[2]　D N Muraviev.Intermatrix synthesis of polymer2stabilized metal nano2par ticles for sens or applications[J].Con2tributions to Science,2005,3(1),17230.[3]　D N Muraviev,J Maca nás,M Farre,et al.Novel routes for inter2matrix synt hesis and c haracterization of polymerstabilized metal nano2particles for molecular recognition devices[J].Sensors&Act uators,2006,118(122):4082 417.(C ont inued from page629)References:[1]　Valeeva I L,Lachinov A N.Synth Met,1993,57(1):4115.[2]　Z hereb ov A Yu,Lachin ov A N.Synth Metals,1991,44:99.[3]　Lachinov A N,Z hereb ov A Yu,K or nilov V M.Pisma v J ET F,1990,52(2):742.[4]　Vorobieva N V,Lac hinov A N,Loginov B A.Surf ace,2006,5:22.[5]　K ornilov V M,Lachin ov A N.J ET F,1997,111(4):1513.[6]　Lachinov A N,Z hereb ov A Yu,et al.Synt h Metals,1993,59:377.[7]　K ornilov V M,Lachin ov A N.Pisma v J E T F,1995,61(6):504.[8]　Lachinov A N,K ornilov V M,et a l.J SID,2004,12(2):149.[9]　Ionov I N,Lachinov A N,Rench R.Pisma v J TF,2002,28(14):69.[10]　K ornilov V M,Lac hinov A N.Mic ro system Technique,2003,3:78.[11]　K ornilov V M,Lac hinov A N.Phy sics of Low2Dimen sional Str ucture s,2004,1/2:145.[12]　Lachinov A N,K ornilov V M,et al.J ET P,2006,102(4):640.1 36　第5期 D.N.Muraviev:Novel Strategies for Prepa ration and Characterization of Functional… 。

Preparation and Characterization of PVC Based Form Stable Phase Change Materials

Preparation and characterization of PVC-based form-stable phasechange materialsXiaoming Jin a,1,Jianli Li b,2,Ping Xue a,n,Mingyin Jia a,na Beijing University of Chemical Technology,Beijing100029,Chinab Beijing Institute of Petrochemical Technology,Beijing102617,Chinaa r t i c l e i n f oArticle history:Received25March2014Received in revised form2July2014Accepted10July2014Keywords:Form-stable phase change materialsMicrocapsulesPVCHDPEWoodﬂoura b s t r a c tSeveral different form-stable phase change materials(FSPCMs),which comprise microencapsulatedphase change materials(MEPCMs)as latent heat storage medium and poly(vinyl chloride)/woodﬂourcompound as supporting material,were prepared by blending and compression molding method for theapplication of potential latent heat thermal energy storage(LHTES).SEM images reveal that preparedFSPCMs have homogeneous constitution and most MEPCM particles in them are undamaged.Both theshell of MEPCM and the matrix prevent the molten parafﬁn from leakage.DSC results show that meltingand freezing temperatures as well as latent heats of the prepared FSPCMs are suitable for potentialLHTES applications.Results of thermal performance tests show that the surface temperatureﬂuctuationof the FSPCMs is obviously less than that of plate without MEPCM.Results of mechanical property testsindicate that bending strength,and bending modulus,as well as tensile and impact strength of theFSPCMs with10wt%MEPCM are26.7MPa,3.48GPa,9.8MPa and10kJ mÀ2respectively.The mechan-ical properties of FSPCMs with poly(vinyl chloride)/woodﬂour compound as supporting material aresuperior to those of HDPE-based FSPCMs.&2014Elsevier B.V.All rights reserved.1.IntroductionThe building and industrial sectors are the leading energyconsumers around the world taking up28%of the overall energyconsumption[1].Forecast made by the EIA suggests that energyuse in the building environment will grow by34%in the next20years[2].Thermal energy storage acts as a useful tool for improv-ing energy efﬁciency and energy savings.It bridges time gapbetween energy requirement and energy supply[3].Latent heatstorage is the most attractive thermal energy storage techniquebecause of high storage density and small temperature changefrom storage to retrieval.In latent heat thermal energy storage(LHTES)systems,energy is stored during melting and recoveredduring freezing of a phase change material(PCM)[4,5].A great variety of inorganic and organic solid–liquid PCMs andtheir mixtures have been studied as latent heat storage materials[2,6–10].Among different solid–liquid PCMs,parafﬁn has manymerits such as large latent heat,little or no super-cooling,lowvapor pressure,good thermal and chemical stability and self-nucleating behavior[11,12].So,parafﬁn is found to be widely usedfor LHTES applications.The major difﬁculty for solid–liquid PCMs'wide applications is the leakage of the molten PCMs.Becauseform-stable phase change materials(FSPCMs)can be directly usedwithout encapsulation,they are more feasible than solid–liquidPCMs for practical applications[11].The FSPCMs can be preparedby impregnating PCMs into polymer-based materials through meltblending or vacuum impregnation.Many scholars have prepareddifferent FSPCMs with various structure supporting componentssuch as high-density polyethylene(HDPE)[13–16],polypropylene(PP)[17,18],styrene–butadiene–styrene(SBS)triblock copolymer[19,20],acrylic resins[21,22],poly(methyl methacrylate)(PMMA)[23,24]and polyurethane block copolymer[8,25,26].However,justa few researchers employ poly(vinyl chloride)(PVC)as supportingmaterial to prepare FSPCMs.Feldman et al.[27]researched thepossibility of developing FSPCMs on the basis of PVC and fattyacids.Sarıand Kaygusuz[28]studied the compositions of differentfatty acids as PCMs and PVC as supporting material.Though polymers or porous materials have been employed assupporting material to package solid–liquid PCMs,the leakageproblem of liquid PCMs is not well solved.Zhang et al.[29]pointedout that parafﬁn in polymer-based FSPCMs tends to diffuse ontosurface and is lost little by little,which results in some problemssuch as leakage,frosting and quick deterioration of thermalproperties.Recently,microencapsulated phase change materials(MEPCMs)have been added into different supporting materials toovercome the leakage problem of liquid PCMs.Schossig et al.[30]Contents lists available at ScienceDirectjournal homepage:/locate/solmatSolar Energy Materials&Solar Cells/10.1016/j.solmat.2014.07.0130927-0248/&2014Elsevier B.V.All rightsreserved.n Corresponding authors.Tel.:þ861064436016.E-mail addresses:buct_nme@(X.Jin),lijianli1979@(J.Li),xueping@(P.Xue),jiamy@(M.Jia).1Tel.:þ861064426911.2Tel.:þ861081292115.Solar Energy Materials&Solar Cells130(2014)435–441integrated MEPCM into plaster and performed building simula-tions and material testing to identify reasonable applications of PCM/plaster compound.Mehling et al.[31]also introduced MEPCM into gypsum for lightweight buildings.Considering leak-age and lipophilicity of parafﬁn,Liu et al.[32]encapsulated FSPCMs with80wt%parafﬁn and20wt%HDPE into silica gel polymer by in situ polymerization.In our previous studies[33]a series of FSPCMs,which comprised MEPCM as the latent heat storage medium and HDPE/woodﬂour composite as the matrix, were prepared by blending and compression molding method.The shell of MEPCM prevents parafﬁn from dispersion in the support-ing material,reduces evaporation and reaction of parafﬁn with the outside environment,provides an increased heat-transfer area and a constant volume,and allows an easy application without affect-ing properties of parent material.Like HDPE/woodﬂour compo-sites,PVC/woodﬂour compound is also a popular wood–plastic composite.However,adding MEPCM into PVC/woodﬂour com-pound to prepare FSPCMs has not been investigated.In this study,PVC-based FSPCMs with MEPCM as latent heat storage medium and PVC/woodﬂour composite as the matrix were prepared by the compression molding method.The micro-structures and thermal properties of the prepared FSPCMs were studied with SEM and DSC techniques respectively.The phase change behaviors of the FSPCMs under the condition which was different from that of the DSC method were studied by melting and freezing performance test.Furthermore,the mechanical properties of the FSPCMs were measured to clarify of whether they have desirable mechanical properties for practical applications.2.Preparation of polymer-based FSPCMs2.1.MaterialsMEPCM(average particle size:7.29μm,as shown in Fig.2;bulk density:900kg mÀ3)was supplied by Beijing Julongbofang Science and Technology Research Institute.PVC(DG-1000K)was provided by Tianjin Dagu Chemical Co.,Ltd.HDPE(melting index: 0.20–0.40g(10min)À1,bulk density:942–950kg mÀ3)was pro-vided by No.2Assistant Reagent Factory of Beijing Oriental Petroleum and Chemical Industry Co.,Ltd.Lead composite stabi-lizer,used as the thermal stabilizer for PVC,was provided by Beijing Daxing Guangming Chemical Factory.Woodﬂour(average particle size:350μm)was obtained from Hebei Xinglong Wood Flour Factory.Silane coupling agent(KH-560)and titanate ester were used to improve interface afﬁnity between woodﬂour and resin.Chlorinated polyethylene(CPE)was used to enhanceﬂame retardancy,improve the mechanical properties and reduce costs. Calcium carbonate was used as aﬁller to improve shape stability of the composite and reduce costs.Acrylic copolymer(ACR)is used as the impact modiﬁer to improve the anti-impact property of PVC.2.2.Pretreatment of woodﬂourFirst,weighed woodﬂour was dried for1h in a drying oven (SFG-02.400,China)at1051C,and was mixed for2min at a low speed.Then titanate ester was sprayed into the blend system and stirred for5min at a high speed.2.3.Preparation of PVC-based FSPCMsFirst,premix A was obtained by modifying calcium carbonate with1%KH-560and premix B was obtained by adding6%Lead composite stabilizer into PVC,both of which were mixed in a high-speed mixer(SHR-50A model,China).Then the PVC mixture was obtained by mixing2.6wt%premix A,69.7wt%premix B,19.7wt% dried woodﬂour,5.9wt%CPE and2.0wt%ACR in the high-speed mixer for3min at alow speed(50r minÀ1).Theﬁnal material used to prepare the PVC-based FSPCMs are obtained by mixing PVC mixture and MEPCM in the high-speed mixer for10min at a high speed(200r minÀ1)according to the formulation in Table1.Finally,a certain number of materials were put into the mold (200mmÂ200mmÂ35mm)and the product was shaped via a hot-press machine(M3-500Â500model,China)at a temperature ranging from1701C to1801C and pressure ranging from5MPa to 7MPa.2.4.Preparation of HDPE-based FSPCMsTheﬁnal material for preparing the HDPE-based FSPCM(No. 7in Fig.1)was obtained by mixing25wt.%dried woodﬂour,50wt %HDPE and25wt%MEPCM for5min at high speed(200r minÀ1) in the high-speed mixer.Then some content ofﬁnal materials (about176g)was put into the mold andﬁnally the HDPE-based FSPCM with the thickness of$4mm was shaped via a hot-press machine at a temperature ranging from1501C to1701C with pressure ranging from8MPa to10MPa.Photos of the prepared PVC-based and HDPE-based FSPCMs are shown in Fig.1.2.5.Characterization of polymer-based FSPCMsSEM(Hitach S-4700,Hitach Co.,Japan)was used to analyze the microstructures of MEPCM and FSPCMs.DSC(NETZSCH DSC204 F1,Germany)was employed to measure the phase transition temperature and latent heat.A universal material testing machine (INSTRON1185,USA)was employed to test bending strength and bending modulus as well as elongation at break of the FSPCMs according to China national standards of GB1042-79.Thermal performance test was performed by using the drying oven and a refrigerator as heating and cooling devices respectively.The set temperatures of the drying oven and the refrigerator were301C andÀ101C,respectively.3.Results and discussion3.1.Microcosmic imagesSEM images of MEPCM and polymer-based FSPCMs are shown in Fig.2.It can be seen from Fig.2(a)that the MEPCM has smooth surface and uniform particle size distribution.Fig.2(b)and(c) shows that MEPCM particles are well dispersed in the prepared PVC-based and HDPE-based FSPCMs.From Fig.2,it can also be seen that most of MEPCM particles are intact though some of them are distorted or even ruptured.Table1Components of PVC-based FSPCMs.No.PVC mixture(wt%)MEPCM(wt%)Thickness of FSPCM plates(mm)11000.0 4.0295 5.0 4.039010.0 4.048515.0 4.058020.0 4.067525.0 4.0X.Jin et al./Solar Energy Materials&Solar Cells130(2014)435–441 4363.2.Phase-transition temperature and enthalpiesThe DSC results of MEPCM and FSPCMs are shown in Fig.3and Table 2.According to Fig.3,the difference of melting peak temperature between MEPCM and FSPCMs is less than 0.51C,and that of solidi ﬁcation peak temperature is 1.51C.It can be safely said the DSC curves of MEPCM and FSPCMs are very similar,which indicates that the shell materials of microcapsule provide good protection to the core materials and keep physical and chemical properties of MEPCM.The measured melting enthalpy value (15.92kJ kg À1)of the PVC-based FSPCM with 15wt%MEPCM is slightly lower than the calculated value,17.07kJ kg À1,which equals the sum of product of the latent heats of MEPCM and the mass fraction of MEPCM in FSPCMs.Similarly,the measured solidi ﬁcation enthalpy value is lower than the calculated value.The measured melting and solidi ﬁcation enthalpy values of the HDPE-based FSPCM with 25wt%MEPCM are 8.42%and 12.11%lower than corresponding calculated values,respectively.These differences stem from the rupture of a small part of MEPCM particles,which leads to the leakage of phase change materials.In a word,the prepared FSPCMs store thermal energy when the ambient temperature is greater than $101C and release latent heat of lower than $131C.According to estimates,the novel PVC-based FSPCM with 15wt%MEPCM can store more than 40kJ kg À1thermal energy at the temperature ranging between 5and151C.Consequently,the novel FSPCMs have potential for low-temperature thermal energy storage and self-regulation for environment temperature.For example,they can be used as energy storage module in mechanical ventilation system to store low-temperature heat at night for reducing air conditioning energy consumption during the daytime.3.3.Thermal performance testHeating and cooling curves of the PVC-based composite without MEPCM and FSPCM with 15wt%MEPCM are shown respectively in Figs.4and 5.In Figs.4and 5,the curve of surface temperature ﬂuctuation every 15s is used to characterize the temperature control effect of the FSPCMs.According to Figs.4and 5,the melting and freezing processes of PVC-based FSPCM occur respectively within the temperature range of 8–18.81C and 0.7–13.11C,which is in concordance with the DSC results.In Fig.4temperature remaining almost constant for $25min can be identi ﬁed on the heating curve of the PVC-based FSPCM sample with 15wt%MEPCM,and the value of relevant average temperature ﬂuctuation equals 0.1081C 15s À1while that of PVC-based composite with-out MEPCM is 0.2371C 15s À1.Similar situations can be found in Fig.5;that is temperature remaining almost constant for 24min can be determined on the cooling curve of the PVC-based FSPCM sample with 15wt%MEPCM,and the value of relevant average temperature ﬂuctuation equals 0.1271C 15s À1while that of PVC-based composite without MEPCM is 0.2231C 15s À1.The average temperature ﬂuctuation of the FSPCM with 15wt%MEPCM in the corresponding temperature range of 8–18.81C and 0.7–13.11C are respectively 54.4%and 43%lower than that of PVC-basedcompositeFig.1.Photos of FSPCMs.(1)PVC-based composite without MEPCM.(2)PVC-based FSPCM with 5wt%MEPCM.(3)PVC-based FSPCM with 10wt%MEPCM.(4)PVC-based FSPCM with 15wt%MEPCM.(5)PVC-based FSPCM with 20wt%MEPCM.(6)PVC-based FSPCM with 25wt%MEPCM.(7)HDPE-based FSPCM with 25wt%MEPCM.X.Jin et al./Solar Energy Materials &Solar Cells 130(2014)435–441437without MEPCM.Since the novel FSPCMs can be used to reduce the amplitude and frequency of temperature ﬂuctuation within the range of phase transition temperature,they have potential applica-tions in ﬁelds such as building air conditioning,greenhouse,storageand transportation of temperature-sensitive goods for temperature smoothness and regulation.3.4.Mechanical properties3.4.1.DensityThe relationship between the density of PVC-based FSPCMs and the mass fraction of MEPCM is shown in Fig.6.It can be seen that the density of PVC-based FSPCMs gradually decreases with increasing mass fraction of MEPCM as the density of MEPCM is lower than that of PVC/wood ﬂour composite.In contrast,the density of PVC-based FSPCMs is greater than that of HDPE-based FSPCMs (996.1kg m À3[33]).In China,common interior decoration plates such as shaving boards,solid wood panels,plasterboard and wood –plastic composite boards have very different densities.The density of shaving board is in the range of 750–1000kg m À3,that of solid wood panels changes from o 350kg m À3to 41130kg m À3,that of plasterboard is about 1000kg m À3and that of wood –plastic composite boards is 600–1400kg m À3.So the density of PVC-based FSPCMs is comparatively moderate during the practical application.3.4.2.Tensile strength,bending strength and modulusLarge test samples with the dimension of 120mm (length)Â15mm (width)Â9mm (thickness)were made for themeasurementFig.2.SEM images of MEPCM and Polymer-based FSPCM plates.(a)MEPCM Â800.(b)PVC-based FSPCM plates with 15wt%MEPCM Â2000.(c)HDPE-based FSPCM plates with 15wt%MEPCM Â4000.Fig. 3.DSC curves of MEPCM and FSPCM plates.(1)MEPCM.(2)HDPE-based FSPCM with 25wt%MEPCM.(3)PVC-based FSPCM with 15wt%MEPCM.X.Jin et al./Solar Energy Materials &Solar Cells 130(2014)435–441438of mechanical properties at 231Cand 70%relative humidity.The bearing width and loading speed for the test of bending strength and bending modulus at break of FSPCM samples were 100mm and 2mm min À1respectively.The test results are shown in Fig.7.It can be seen that (1)the mass fraction of MEPCM notably in ﬂuences the bending strength and modulus;(2)greater mass fraction of MEPCM leads to poorer bending strength and there is an almost constant region in the bending strength curve of PVC-based FSPCMs in the interval of 5–15wt%.In this region,bending strength changes between 25.7and27.8MPa and it is smaller than that of PVC-based composite without MEPCM (35.3MPa)by 21.7–27.0%.Compared with the bend-ing strength of HDPE-based FSPCMs with 25wt%MEPCM (14.38MPa [33]),the bending strength of PVC-based FSPCMs increases by 78.0%–93.3%.Thus,PVC is used as a base material to improve the bending strength dramatically;(3)the bending modulus of FSPCMs increases when the mass fraction of MEPCM increases from 0%to 10wt%whileit decreases at the other MEPCM fractions.When the mass fraction of MEPCM is 10wt%,the bending modulus is pared with the base materials'bending modulus (3.06GPa),the increase in amplitude is about 13.7%.The reason is that a fraction of MEPCM in PVC-based materials is dispersed homogenously,and MEPCM particles toughen the materials.The bending modulus of the plates decreases when the mass fraction of MEPCM exceeds 10wt%.The reason might be that small MEPCM particles coalesce with each other due to their large surface energy and the bending modulus is pared with the bending modulus of HDPE-based FSPCMs with 25wt%MEPCM (757.86MPa [33]),the bending modulus of PVC-based FSPCMs increases more than 3times;(4)the tensile strength of FSPCM is decreased with increasing mass fraction of MEPCM.Some reduction of MEPCM should be considered during the practical applicationTable 2DSC results of MEPCM and PVC-base FSPCMs.SampleMass (mg)Rates of heating/cooling (1C min À1)Melting process Solidifying processT s (1C)T p (1C)λ(kJ kg À1)T s /1C T p /1C λ(kJ kg À1)MEPCM5.211011.3815.14113.813.17 4.85114.1PVC-based FSPCM a 7.61011.3114.8115.92(17.07)c 12.32 6.2616.66(17.12)HDPE-based FSPCM b 5.61010.7014.6527.31(29.82)11.104.7226.27(29.89)Notes :a The mass fraction of MEPCM in the PVC-based FSPCMs is 15%.b The mass fraction of MEPCM in the HDPE-based FSPCMs is 25%.cThe numeral value in brackets equals the product of the latent heats of MEPCM and the mass fraction of MEPCM inFSPCMs.Fig.4.Heating curves of PVC-based composite without MEPCM and FSPCM with 15wt%MEPCM.Fig.5.Cooling curves of PVC-based composite without MEPCM and FSPCM with 15wt%MEPCM.Fig.6.Effect of MEPCM on the density of PVC-basedFSPCMs.Fig.7.Effect of MEPCM on the mechanical properties of PVC-based FSPCMs.X.Jin et al./Solar Energy Materials &Solar Cells 130(2014)435–441439where larger tensile strength is required.When the mass fraction of MEPCM increases from 0to 25wt%,the tensile strength of FSPCMs decreases by 52.1%.Furthermore,many other factors such as the fraction and particle size of wood ﬂour,the properties of coupling agent and processing parameter greatly in ﬂuence the mechanical properties of FSPCMs.3.4.3.Impact strengthThe effect of MEPCM on the impact strength of PVC-based FSPCMs is shown in Fig.8.When the mass fraction of MEPCM is 5wt%,the impact strength reaches 10.93kJ m Àpared with the impact strength of base materials (8.71kJ m À2),the relative increment is 25.5%.With more MEPCM,the impact strength decreases.When the mass fraction of MEPCM is 25wt%,it is down to 7.81kJ m À2and $10.3%less than that of the base materials.The reason which can be explained is that appropriate amount of MEPCM in PVC-based FSPCMs is dispersed homoge-nously and it toughens the materials.MEPCM particles begin to aggregate with the increase of MEPCM because of its large surface energy,which leads to the decline of the impact strength.Besides,it should be noted that the impact strength of rigid PVC ranges from 22to 108kJ m À2.Therefore,adding MEPCM to PVC/wood ﬂour composite will decrease the impact strength of PVC-based FSPCMs.4.ConclusionPreparation and properties (thermal and mechanical)charac-terization of ﬁve novel PVC-based FSPCMs are presented in this paper.Micrographs taken on SEM reveal that most MEPCM particles in the PVC-based FSPCMs are undamaged.Thus both the shell of MEPCM and the matrix prevent molten paraf ﬁn from leakage.DSC results show that the melting and freezing tempera-tures as well as latent heats of the novel FSPCMs are suitable for potential LHTES applications.Temperature remaining almost con-stant for $25min can be identi ﬁed in the heating and cooling curves of the PVC-based FSPCM sample with 15wt%MEPCM.And according to these curves,the average surface temperature ﬂuc-tuations every 15s of the FSPCM with 15wt%MEPCM in the corresponding temperature range of 8–18.81C and 0.7–13.11C are respectively 54.4%and 43%lower than that of PVC-based composite without MEPCM.So the novel FSPCMs can be used to reduce the amplitude and frequency of temperature ﬂuctuation within the range of phase transition temperature.The results of mechanical properties test indicate that the mechanical properties of PVC-basedFSPCM are better than that of HDPE-based FSPCM.The PVC-based FSPCM with 10wt%MEPCM has the best mechanical properties.Based on their proper phase change temperatures,outstanding leak tightness of molten paraf ﬁn,good temperature control feature and mechanical properties,the novel PVC-based FSPCMs have the potential for LHTES applications such as building air conditioning,greenhouse,storage and transportation of temperature-sensitive goods for temperature smoothness and regulation.AcknowledgmentsThe authors would like to acknowledge Beijing Excellent Talents Program (NO.2013D009016000002)for support.References[1]S.A.Memon,T.Y.Lo,S.Barbhuiya,W.Xu,Development of form-stablecomposite phase change material by incorporation of dodecyl alcohol into ground granulated blast furnace slag,Energy Build.62(2013)360–367.[2]Energy Information Administration,International Energy Outlook 2006,U.S.Department of Energy,2006.[3]B.Tang,M.Qiu,S.Zhang,Thermal conductivity enhancement of PEG/SiO 2composite PCM by in situ Cu doping,Sol.Energty Mater.Sol.Cells 105(2012)242–248.[4]A Sharma,V Tyagi,CR Chen,D.,Buddhi,Review on thermal energy storagewith phase change materials and applications,Renew.Sustain.Energy Rev.13(2)(2009)318–345.[5]MK Rathod,J,Banerjee,Thermal stability of phase change materials used inlatent heat energy 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正交试验英语

正交试验英语In the field of experimental design, orthogonal experiments play a crucial role in helping researchers efficiently and effectively explore the relationships between multiple factors and their impact on a particular outcome. This article aims to provide a comprehensive overview of orthogonal experiments, including their definition, advantages, applications, and key considerations for implementation.Orthogonal experiments, also known as orthogonal arrays, are a systematic and efficient approach to conducting experiments with multiple factors. The term "orthogonal" refers to the independence and lack of correlation between different factors, which allows researchers to isolate and analyze the individual effects of each factor on the outcome of interest. By carefully selecting and arranging the levels of each factor in an orthogonal array, researchers can minimize the number of experimental runs required while still obtaining reliable and meaningful results.One of the primary advantages of orthogonal experiments is their ability to reduce the number of experimental runs needed to explore the effects of multiple factors. This efficiency is particularly valuable in situations where conducting a large number of experimental runs is time-consuming, costly, or impractical. By using orthogonal arrays to systematically vary the levels of each factor, researchers can achieve a high degree of experimental efficiency without sacrificing the quality or validity of their results.Furthermore, orthogonal experiments are highly versatile and can be applied to a wide range of research fields and industries. From manufacturing and engineering to healthcare and environmental science, orthogonal experiments have been used to investigate and optimize processes, products, and systems. Their flexibility and adaptability make them a valuable tool for researchers and practitioners seeking to improve and innovate in their respective fields.When implementing orthogonal experiments, researchers should carefully consider several key factors to ensure the validity and reliability of their results. First, the selection of factors and their respective levels should be based on a thorough understanding of theunderlying system or process being studied. This requires careful planning and consideration of the potential interactions and relationships between different factors.Additionally, researchers must pay close attention to the design and execution of the experimental runs to minimize the potential for confounding variables or bias. This may involve randomizing the order of experimental runs, controlling for external factors, and ensuring the consistency and accuracy of data collection and analysis.In conclusion, orthogonal experiments are a powerful and versatile tool for exploring the effects of multiple factors on a particular outcome. Their efficiency, flexibility, and ability to provide meaningful results make them a valuable asset in the research and development process. By carefully planning and implementing orthogonal experiments, researchers can gain valuable insights and make informed decisions that drive progress and innovation in their respective fields.。

北大考研-环境科学与工程学院研究生导师简介-叶正芳

爱考机构中国高端考研第一品牌（保过保录限额）
2010.1-2010.12 南水北调东线治污新理念与成效研究国务院南水北调办项目负责人 25
2009.10-2010.9. 垃圾渗滤液处理的组合技术及工艺开发北京市项目负责人 15
2008.1-2012.12 功能化载体的研究与试制企业委托项目负责人 50
研究领域
污水处理、地下水处理、固定化微生物（酶）、功能材料等相关的科学与技术研究奖励荣誉
全部获奖人员排名获奖时间获奖项目类别（国家、省部、校）奖励名称等级
倪晋仁，叶正芳，崔锋，王志民，籍国东等 16 人
2007
爱考机构中国高端考研第一品牌（保过保录限额）
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高等学校科学技术进步奖固定化微生物处理高氨氮废水的研究一等
叶正芳，倪晋仁 2008 北京市发明专利奖一种制备聚氨酯及生物固定化载体的工艺二等
王刚，邱熔处，叶正芳，周程，邢秀兰等 9 人 2010 甘肃省/兰州市科学技术进步奖 H—BAF 综合技术用于污水再生利用工程二等/一等
叶正芳 2006 甘肃省十大优秀专利奖曝气生物流化池十大优秀专利
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专八英语阅读

英语专业八级考试TEM-8阅读理解练习册（1）(英语专业2012级)UNIT 1Text AEvery minute of every day, what ecologist生态学家James Carlton calls a global ―conveyor belt‖, redistributes ocean organisms生物.It’s planetwide biological disruption生物的破坏that scientists have barely begun to understand.Dr. Carlton —an oceanographer at Williams College in Williamstown,Mass.—explains that, at any given moment, ―There are several thousand marine species traveling… in the ballast water of ships.‖ These creatures move from coastal waters where they fit into the local web of life to places where some of them could tear that web apart. This is the larger dimension of the infamous无耻的，邪恶的invasion of fish-destroying, pipe-clogging zebra mussels有斑马纹的贻贝.Such voracious贪婪的invaders at least make their presence known. What concerns Carlton and his fellow marine ecologists is the lack of knowledge about the hundreds of alien invaders that quietly enter coastal waters around the world every day. Many of them probably just die out. Some benignly亲切地，仁慈地—or even beneficially — join the local scene. But some will make trouble.In one sense, this is an old story. Organisms have ridden ships for centuries. They have clung to hulls and come along with cargo. What’s new is the scale and speed of the migrations made possible by the massive volume of ship-ballast water压载水— taken in to provide ship stability—continuously moving around the world…Ships load up with ballast water and its inhabitants in coastal waters of one port and dump the ballast in another port that may be thousands of kilometers away. A single load can run to hundreds of gallons. Some larger ships take on as much as 40 million gallons. The creatures that come along tend to be in their larva free-floating stage. When discharged排出in alien waters they can mature into crabs, jellyfish水母, slugs鼻涕虫，蛞蝓, and many other forms.Since the problem involves coastal species, simply banning ballast dumps in coastal waters would, in theory, solve it. Coastal organisms in ballast water that is flushed into midocean would not survive. Such a ban has worked for North American Inland Waterway. But it would be hard to enforce it worldwide. Heating ballast water or straining it should also halt the species spread. But before any such worldwide regulations were imposed, scientists would need a clearer view of what is going on.The continuous shuffling洗牌of marine organisms has changed the biology of the sea on a global scale. It can have devastating effects as in the case of the American comb jellyfish that recently invaded the Black Sea. It has destroyed that sea’s anchovy鳀鱼fishery by eating anchovy eggs. It may soon spread to western and northern European waters.The maritime nations that created the biological ―conveyor belt‖ should support a coordinated international effort to find out what is going on and what should be done about it. (456 words)1.According to Dr. Carlton, ocean organism‟s are_______.A.being moved to new environmentsB.destroying the planetC.succumbing to the zebra musselD.developing alien characteristics2.Oceanographers海洋学家are concerned because_________.A.their knowledge of this phenomenon is limitedB.they believe the oceans are dyingC.they fear an invasion from outer-spaceD.they have identified thousands of alien webs3.According to marine ecologists, transplanted marinespecies____________.A.may upset the ecosystems of coastal watersB.are all compatible with one anotherC.can only survive in their home watersD.sometimes disrupt shipping lanes4.The identified cause of the problem is_______.A.the rapidity with which larvae matureB. a common practice of the shipping industryC. a centuries old speciesD.the world wide movement of ocean currents5.The article suggests that a solution to the problem__________.A.is unlikely to be identifiedB.must precede further researchC.is hypothetically假设地，假想地easyD.will limit global shippingText BNew …Endangered‟ List Targets Many US RiversIt is hard to think of a major natural resource or pollution issue in North America today that does not affect rivers.Farm chemical runoff残渣, industrial waste, urban storm sewers, sewage treatment, mining, logging, grazing放牧,military bases, residential and business development, hydropower水力发电,loss of wetlands. The list goes on.Legislation like the Clean Water Act and Wild and Scenic Rivers Act have provided some protection, but threats continue.The Environmental Protection Agency (EPA) reported yesterday that an assessment of 642,000 miles of rivers and streams showed 34 percent in less than good condition. In a major study of the Clean Water Act, the Natural Resources Defense Council last fall reported that poison runoff impairs损害more than 125,000 miles of rivers.More recently, the NRDC and Izaak Walton League warned that pollution and loss of wetlands—made worse by last year’s flooding—is degrading恶化the Mississippi River ecosystem.On Tuesday, the conservation group保护组织American Rivers issued its annual list of 10 ―endangered‖ and 20 ―threatened‖ rivers in 32 states, the District of Colombia, and Canada.At the top of the list is the Clarks Fork of the Yellowstone River, whereCanadian mining firms plan to build a 74-acre英亩reservoir水库，蓄水池as part of a gold mine less than three miles from Yellowstone National Park. The reservoir would hold the runoff from the sulfuric acid 硫酸used to extract gold from crushed rock.―In the event this tailings pond failed, the impact to th e greater Yellowstone ecosystem would be cataclysmic大变动的，灾难性的and the damage irreversible不可逆转的.‖ Sen. Max Baucus of Montana, chairman of the Environment and Public Works Committee, wrote to Noranda Minerals Inc., an owner of the ― New World Mine‖.Last fall, an EPA official expressed concern about the mine and its potential impact, especially the plastic-lined storage reservoir. ― I am unaware of any studies evaluating how a tailings pond尾矿池，残渣池could be maintained to ensure its structural integrity forev er,‖ said Stephen Hoffman, chief of the EPA’s Mining Waste Section. ―It is my opinion that underwater disposal of tailings at New World may present a potentially significant threat to human health and the environment.‖The results of an environmental-impact statement, now being drafted by the Forest Service and Montana Department of State Lands, could determine the mine’s future…In its recent proposal to reauthorize the Clean Water Act, the Clinton administration noted ―dramatically improved water quality since 1972,‖ when the act was passed. But it also reported that 30 percent of riverscontinue to be degraded, mainly by silt泥沙and nutrients from farm and urban runoff, combined sewer overflows, and municipal sewage城市污水. Bottom sediments沉积物are contaminated污染in more than 1,000 waterways, the administration reported in releasing its proposal in January. Between 60 and 80 percent of riparian corridors (riverbank lands) have been degraded.As with endangered species and their habitats in forests and deserts, the complexity of ecosystems is seen in rivers and the effects of development----beyond the obvious threats of industrial pollution, municipal waste, and in-stream diversions改道to slake消除the thirst of new communities in dry regions like the Southwes t…While there are many political hurdles障碍ahead, reauthorization of the Clean Water Act this year holds promise for US rivers. Rep. Norm Mineta of California, who chairs the House Committee overseeing the bill, calls it ―probably the most important env ironmental legislation this Congress will enact.‖ (553 words)6.According to the passage, the Clean Water Act______.A.has been ineffectiveB.will definitely be renewedC.has never been evaluatedD.was enacted some 30 years ago7.“Endangered” rivers are _________.A.catalogued annuallyB.less polluted than ―threatened rivers‖C.caused by floodingD.adjacent to large cities8.The “cataclysmic” event referred to in paragraph eight would be__________.A. fortuitous偶然的，意外的B. adventitious外加的，偶然的C. catastrophicD. precarious不稳定的，危险的9. The owners of the New World Mine appear to be______.A. ecologically aware of the impact of miningB. determined to construct a safe tailings pondC. indifferent to the concerns voiced by the EPAD. willing to relocate operations10. The passage conveys the impression that_______.A. Canadians are disinterested in natural resourcesB. private and public environmental groups aboundC. river banks are erodingD. the majority of US rivers are in poor conditionText CA classic series of experiments to determine the effects ofoverpopulation on communities of rats was reported in February of 1962 in an article in Scientific American. The experiments were conducted by a psychologist, John B. Calhoun and his associates. In each of these experiments, an equal number of male and female adult rats were placed in an enclosure and given an adequate supply of food, water, and other necessities. The rat populations were allowed to increase. Calhoun knew from experience approximately how many rats could live in the enclosures without experiencing stress due to overcrowding. He allowed the population to increase to approximately twice this number. Then he stabilized the population by removing offspring that were not dependent on their mothers. He and his associates then carefully observed and recorded behavior in these overpopulated communities. At the end of their experiments, Calhoun and his associates were able to conclude that overcrowding causes a breakdown in the normal social relationships among rats, a kind of social disease. The rats in the experiments did not follow the same patterns of behavior as rats would in a community without overcrowding.The females in the rat population were the most seriously affected by the high population density: They showed deviant异常的maternal behavior; they did not behave as mother rats normally do. In fact, many of the pups幼兽，幼崽, as rat babies are called, died as a result of poor maternal care. For example, mothers sometimes abandoned their pups,and, without their mothers' care, the pups died. Under normal conditions, a mother rat would not leave her pups alone to die. However, the experiments verified that in overpopulated communities, mother rats do not behave normally. Their behavior may be considered pathologically 病理上，病理学地diseased.The dominant males in the rat population were the least affected by overpopulation. Each of these strong males claimed an area of the enclosure as his own. Therefore, these individuals did not experience the overcrowding in the same way as the other rats did. The fact that the dominant males had adequate space in which to live may explain why they were not as seriously affected by overpopulation as the other rats. However, dominant males did behave pathologically at times. Their antisocial behavior consisted of attacks on weaker male,female, and immature rats. This deviant behavior showed that even though the dominant males had enough living space, they too were affected by the general overcrowding in the enclosure.Non-dominant males in the experimental rat communities also exhibited deviant social behavior. Some withdrew completely; they moved very little and ate and drank at times when the other rats were sleeping in order to avoid contact with them. Other non-dominant males were hyperactive; they were much more active than is normal, chasing other rats and fighting each other. This segment of the rat population, likeall the other parts, was affected by the overpopulation.The behavior of the non-dominant males and of the other components of the rat population has parallels in human behavior. People in densely populated areas exhibit deviant behavior similar to that of the rats in Calhoun's experiments. In large urban areas such as New York City, London, Mexican City, and Cairo, there are abandoned children. There are cruel, powerful individuals, both men and women. There are also people who withdraw and people who become hyperactive. The quantity of other forms of social pathology such as murder, rape, and robbery also frequently occur in densely populated human communities. Is the principal cause of these disorders overpopulation? Calhoun’s experiments suggest that it might be. In any case, social scientists and city planners have been influenced by the results of this series of experiments.11. Paragraph l is organized according to__________.A. reasonsB. descriptionC. examplesD. definition12．Calhoun stabilized the rat population_________.A. when it was double the number that could live in the enclosure without stressB. by removing young ratsC. at a constant number of adult rats in the enclosureD. all of the above are correct13.W hich of the following inferences CANNOT be made from theinformation inPara. 1?A. Calhoun's experiment is still considered important today.B. Overpopulation causes pathological behavior in rat populations.C. Stress does not occur in rat communities unless there is overcrowding.D. Calhoun had experimented with rats before.14. Which of the following behavior didn‟t happen in this experiment?A. All the male rats exhibited pathological behavior.B. Mother rats abandoned their pups.C. Female rats showed deviant maternal behavior.D. Mother rats left their rat babies alone.15. The main idea of the paragraph three is that __________.A. dominant males had adequate living spaceB. dominant males were not as seriously affected by overcrowding as the otherratsC. dominant males attacked weaker ratsD. the strongest males are always able to adapt to bad conditionsText DThe first mention of slavery in the statutes法令，法规of the English colonies of North America does not occur until after 1660—some forty years after the importation of the first Black people. Lest we think that existed in fact before it did in law, Oscar and Mary Handlin assure us, that the status of B lack people down to the 1660’s was that of servants. A critique批判of the Handlins’ interpretation of why legal slavery did not appear until the 1660’s suggests that assumptions about the relation between slavery and racial prejudice should be reexamined, and that explanation for the different treatment of Black slaves in North and South America should be expanded.The Handlins explain the appearance of legal slavery by arguing that, during the 1660’s, the position of white servants was improving relative to that of black servants. Thus, the Handlins contend, Black and White servants, heretofore treated alike, each attained a different status. There are, however, important objections to this argument. First, the Handlins cannot adequately demonstrate that t he White servant’s position was improving, during and after the 1660’s; several acts of the Maryland and Virginia legislatures indicate otherwise. Another flaw in the Handlins’ interpretation is their assumption that prior to the establishment of legal slavery there was no discrimination against Black people. It is true that before the 1660’s Black people were rarely called slaves. But this shouldnot overshadow evidence from the 1630’s on that points to racial discrimination without using the term slavery. Such discrimination sometimes stopped short of lifetime servitude or inherited status—the two attributes of true slavery—yet in other cases it included both. The Handlins’ argument excludes the real possibility that Black people in the English colonies were never treated as the equals of White people.The possibility has important ramifications后果，影响.If from the outset Black people were discriminated against, then legal slavery should be viewed as a reflection and an extension of racial prejudice rather than, as many historians including the Handlins have argued, the cause of prejudice. In addition, the existence of discrimination before the advent of legal slavery offers a further explanation for the harsher treatment of Black slaves in North than in South America. Freyre and Tannenbaum have rightly argued that the lack of certain traditions in North America—such as a Roman conception of slavery and a Roman Catholic emphasis on equality— explains why the treatment of Black slaves was more severe there than in the Spanish and Portuguese colonies of South America. But this cannot be the whole explanation since it is merely negative, based only on a lack of something. A more compelling令人信服的explanation is that the early and sometimes extreme racial discrimination in the English colonies helped determine the particular nature of the slavery that followed. (462 words)16. Which of the following is the most logical inference to be drawn from the passage about the effects of “several acts of the Maryland and Virginia legislatures” (Para.2) passed during and after the 1660‟s?A. The acts negatively affected the pre-1660’s position of Black as wellas of White servants.B. The acts had the effect of impairing rather than improving theposition of White servants relative to what it had been before the 1660’s.C. The acts had a different effect on the position of white servants thandid many of the acts passed during this time by the legislatures of other colonies.D. The acts, at the very least, caused the position of White servants toremain no better than it had been before the 1660’s.17. With which of the following statements regarding the status ofBlack people in the English colonies of North America before the 1660‟s would the author be LEAST likely to agree?A. Although black people were not legally considered to be slaves,they were often called slaves.B. Although subject to some discrimination, black people had a higherlegal status than they did after the 1660’s.C. Although sometimes subject to lifetime servitude, black peoplewere not legally considered to be slaves.D. Although often not treated the same as White people, black people,like many white people, possessed the legal status of servants.18. According to the passage, the Handlins have argued which of thefollowing about the relationship between racial prejudice and the institution of legal slavery in the English colonies of North America?A. Racial prejudice and the institution of slavery arose simultaneously.B. Racial prejudice most often the form of the imposition of inheritedstatus, one of the attributes of slavery.C. The source of racial prejudice was the institution of slavery.D. Because of the influence of the Roman Catholic Church, racialprejudice sometimes did not result in slavery.19. The passage suggests that the existence of a Roman conception ofslavery in Spanish and Portuguese colonies had the effect of _________.A. extending rather than causing racial prejudice in these coloniesB. hastening the legalization of slavery in these colonies.C. mitigating some of the conditions of slavery for black people in these coloniesD. delaying the introduction of slavery into the English colonies20. The author considers the explanation put forward by Freyre andTannenbaum for the treatment accorded B lack slaves in the English colonies of North America to be _____________.A. ambitious but misguidedB. valid有根据的but limitedC. popular but suspectD. anachronistic过时的，时代错误的and controversialUNIT 2Text AThe sea lay like an unbroken mirror all around the pine-girt, lonely shores of Orr’s Island. Tall, kingly spruce s wore their regal王室的crowns of cones high in air, sparkling with diamonds of clear exuded gum流出的树胶; vast old hemlocks铁杉of primeval原始的growth stood darkling in their forest shadows, their branches hung with long hoary moss久远的青苔;while feathery larches羽毛般的落叶松,turned to brilliant gold by autumn frosts, lighted up the darker shadows of the evergreens. It was one of those hazy朦胧的, calm, dissolving days of Indian summer, when everything is so quiet that the fainest kiss of the wave on the beach can be heard, and white clouds seem to faint into the blue of the sky, and soft swathing一长条bands of violet vapor make all earth look dreamy, and give to the sharp, clear-cut outlines of the northern landscape all those mysteries of light and shade which impart such tenderness to Italian scenery.The funeral was over,--- the tread鞋底的花纹/ 踏of many feet, bearing the heavy burden of two broken lives, had been to the lonely graveyard, and had come back again,--- each footstep lighter and more unconstrained不受拘束的as each one went his way from the great old tragedy of Death to the common cheerful of Life.The solemn black clock stood swaying with its eternal ―tick-tock, tick-tock,‖ in the kitchen of the brown house on Orr’s Island. There was there that sense of a stillness that can be felt,---such as settles down on a dwelling住处when any of its inmates have passed through its doors for the last time, to go whence they shall not return. The best room was shut up and darkened, with only so much light as could fall through a little heart-shaped hole in the window-shutter,---for except on solemn visits, or prayer-meetings or weddings, or funerals, that room formed no part of the daily family scenery.The kitchen was clean and ample, hearth灶台, and oven on one side, and rows of old-fashioned splint-bottomed chairs against the wall. A table scoured to snowy whiteness, and a little work-stand whereon lay the Bible, the Missionary Herald, and the Weekly Christian Mirror, before named, formed the principal furniture. One feature, however, must not be forgotten, ---a great sea-chest水手用的储物箱,which had been the companion of Zephaniah through all the countries of the earth. Old, and battered破旧的，磨损的, and unsightly难看的it looked, yet report said that there was good store within which men for the most part respect more than anything else; and, indeed it proved often when a deed of grace was to be done--- when a woman was suddenly made a widow in a coast gale大风，狂风, or a fishing-smack小渔船was run down in the fogs off the banks, leaving in some neighboring cottage a family of orphans,---in all such cases, the opening of this sea-chest was an event of good omen 预兆to the bereaved丧亲者;for Zephaniah had a large heart and a large hand, and was apt有…的倾向to take it out full of silver dollars when once it went in. So the ark of the covenant约柜could not have been looked on with more reverence崇敬than the neighbours usually showed to Captain Pennel’s sea-chest.1. The author describes Orr‟s Island in a(n)______way.A.emotionally appealing, imaginativeB.rational, logically preciseC.factually detailed, objectiveD.vague, uncertain2.According to the passage, the “best room”_____.A.has its many windows boarded upB.has had the furniture removedC.is used only on formal and ceremonious occasionsD.is the busiest room in the house3.From the description of the kitchen we can infer that thehouse belongs to people who_____.A.never have guestsB.like modern appliancesC.are probably religiousD.dislike housework4.The passage implies that_______.A.few people attended the funeralB.fishing is a secure vocationC.the island is densely populatedD.the house belonged to the deceased5.From the description of Zephaniah we can see thathe_________.A.was physically a very big manB.preferred the lonely life of a sailorC.always stayed at homeD.was frugal and saved a lotText BBasic to any understanding of Canada in the 20 years after the Second World War is the country' s impressive population growth. For every three Canadians in 1945, there were over five in 1966. In September 1966 Canada's population passed the 20 million mark. Most of this surging growth came from natural increase. The depression of the 1930s and the war had held back marriages, and the catching-up process began after 1945. The baby boom continued through the decade of the 1950s, producing a population increase of nearly fifteen percent in the five years from 1951 to 1956. This rate of increase had been exceeded only once before in Canada's history, in the decade before 1911 when the prairies were being settled. Undoubtedly, the good economic conditions of the 1950s supported a growth in the population, but the expansion also derived from a trend toward earlier marriages and an increase in the average size of families; In 1957 the Canadian birth rate stood at 28 per thousand, one of the highest in the world. After the peak year of 1957, thebirth rate in Canada began to decline. It continued falling until in 1966 it stood at the lowest level in 25 years. Partly this decline reflected the low level of births during the depression and the war, but it was also caused by changes in Canadian society. Young people were staying at school longer, more women were working; young married couples were buying automobiles or houses before starting families; rising living standards were cutting down the size of families. It appeared that Canada was once more falling in step with the trend toward smaller families that had occurred all through theWestern world since the time of the Industrial Revolution. Although the growth in Canada’s population had slowed down by 1966 (the cent), another increase in the first half of the 1960s was only nine percent), another large population wave was coming over the horizon. It would be composed of the children of the children who were born during the period of the high birth rate prior to 1957.6. What does the passage mainly discuss?A. Educational changes in Canadian society.B. Canada during the Second World War.C. Population trends in postwar Canada.D. Standards of living in Canada.7. According to the passage, when did Canada's baby boom begin?A. In the decade after 1911.B. After 1945.C. During the depression of the 1930s.D. In 1966.8. The author suggests that in Canada during the 1950s____________.A. the urban population decreased rapidlyB. fewer people marriedC. economic conditions were poorD. the birth rate was very high9. When was the birth rate in Canada at its lowest postwar level?A. 1966.B. 1957.C. 1956.D. 1951.10. The author mentions all of the following as causes of declines inpopulation growth after 1957 EXCEPT_________________.A. people being better educatedB. people getting married earlierC. better standards of livingD. couples buying houses11.I t can be inferred from the passage that before the IndustrialRevolution_______________.A. families were largerB. population statistics were unreliableC. the population grew steadilyD. economic conditions were badText CI was just a boy when my father brought me to Harlem for the first time, almost 50 years ago. We stayed at the hotel Theresa, a grand brick structure at 125th Street and Seventh avenue. Once, in the hotel restaurant, my father pointed out Joe Louis. He even got Mr. Brown, the hotel manager, to introduce me to him, a bit punchy强力的but still champ焦急as fast as I was concerned.Much has changed since then. Business and real estate are booming. Some say a new renaissance is under way. Others decry责难what they see as outside forces running roughshod肆意践踏over the old Harlem. New York meant Harlem to me, and as a young man I visited it whenever I could. But many of my old haunts are gone. The Theresa shut down in 1966. National chains that once ignored Harlem now anticipate yuppie money and want pieces of this prime Manhattan real estate. So here I am on a hot August afternoon, sitting in a Starbucks that two years ago opened a block away from the Theresa, snatching抓取，攫取at memories between sips of high-priced coffee. I am about to open up a piece of the old Harlem---the New York Amsterdam News---when a tourist。

课程思政视域下非遗融入艺术设计专业教学实践与探索

课程思政视域下非遗融入艺术设计专业教学实践与探索TEACHING PRACTICE AND EXPLORATION OF INTEGRATING NON-LEGACY INTO ART DESIGN MAJOR IN THE PERSPECTIVE OF CURRICULUM IDEOLOGY AND POLITICS 引言非物质文化遗产作为中华优秀传统文化的重要组成部分，具有得天独厚的民族文化资源优势，是提升民族凝聚力、增强文化自信的重要载体，将其融入高职院校艺术设计教育教学中，是结合专业特点分类推进课程思政[1]，把中华优秀传统文化全方位融入艺术教育各环节[2]的具体实践，将两者互融互通，有利于增强文化自信，落实立德树人根本任务，全面提高人才自主培养质量。

一、非遗融入艺术设计专业教育教学的必要性和可行性非遗蕴含着中华民族独特的价值追求、思想观念、人文精神和道德规范，具有深刻而丰富的教育内容，是课程思政的不竭源泉，其内在的文化艺术价值对现代艺术设计具有重大的启示作用，为艺术设计教育提供了更为丰富的创意元素和艺术素材。

将非遗融入高职院校艺术设计专业教育教学，是实现非遗传承和创新发展的有效途径，其教学成果可以反哺地方经济文化发展，践行课程思政成效，如图 1 所示。

非遗蕴含的中华优秀传统文化与高等教育追求的育人目标是高度一致的，两者存在教学内容的交叉性、育人功能的契合性和相互发展的依存性，将非遗融入地方高职院校艺术设计专业教育教学是必要且可行的。

二、非遗融入地方高职院校艺术设计专业的现状调查为了更好地了解非遗融入高职院校艺术设计专业的教育教学情况，作者对云南省高职院校在校大学生进行了问卷调查，对云南省艺术设计专业教师进行了访谈，调查情况如下：（一）学生问卷调查对象为云南省职业院校艺术设计专业的在校大学生，主要采取网络问卷的形式，发出问卷480份，收回有效问卷467份，数据反馈真实可信。

有效问卷中有64.49%的同学愿意将非遗植入专业课程，丰富设计素材，激发创作灵感，创新设计理念，提升文化内涵，有31.16%的同学表示视情况而定，而将非遗相关知识运用于课堂教学的教师占比仅为20%。

《生物质化学工程》简介

Vol.55No.230Mar.2021 BIOMASS CHEMICAL ENGINEERINGBimonthly,Started in1961General serial No.369ContenteResearch ReportPreparation and Characterization of Poly(!-lactic AciK-co-Glucose)Copolymer by Hydroxyl Protection Method ...............................................................................................................ZHU QCnjin,QI Liya,CAO Da,LIU Tinging,GAO Qinwei(l) Analysis of Gasification Procese and Gasification Characteristics of Downdrafi Fixed Bed Gasifier...................................................................................................................................................CHENG Xiangwen,LIU Lizhi,WEI Rong(9) Structural Propertiee of Niobium Oxide/Woody Activated Carbon Fibee Composites.......................................LIU Xin,MA Xiaojun(16) Quaternization of Sugar Beei Puly and Us Adsorption Property te Nucleaa Fast Red......................................................................................................................................ZHANG Yaxia,YU Xue,LI Yang,ZHU Siming(23) E i ecioiChemocayand BooyogocayCompound TappongV a oianiAgenion Reionconcaeaiongand PhyiocayVndeyeioiPinus yunnanensis....................................................................................WANG Ruiling,LIU Xiangyi,LIU Jianxiang,WU Chunhua(31) EEect of Process Parameters on Formaldehyde and TVOC Conteni in Plywood Bonded with Bio-oii PhenoiFormaldehyde Resini..................................................................HUANG Ping,YANG Fan,JIU Liangiang,LI Jin,LI Dongbing(38) Syniheioiand AnioiungayAcioaoiyoiHydaonopyyGemonoQuaieanaayAmmonoum Sayii......................................................................................................FENG Xuezhen,XIAO Zhuanquan,FAN Guorong,WANG Zongde(45) Preparation and Flame Retardani Properties of Dimethyl Methylphosphonate/Sodium LianosulfonatePOyurethae Foam...........................................................................................................YU Ze,LI Xu,WANG Jinan,LIU Zhiming(50) Synthesis and Herbicidal Activity of Hydroxycitrone/al Oxinie and Its Alkyl Ethers............................................PENG Yun,XIAO Zhuanquan,LIUO Shengiang,FAN Guorong,CHEN Shangxing,WANG Zongde(55) Review CommenhReieaoch Poogoe i oiFuncioonayoaed Wood on iheFoeyd oiPo y uied WaieoPuooiocaioon................................................................................ZHANG Ming,DU XiXng,SHI Junyou,SUN Yaoxing,LI Jin,WANG Chengyu(60)《生物质化学工程》简介《生物质化学工程》是由国家林业和草原局主管、中国林科院林产化学工业研究所主办的，面向国内外公开发行的全国生物质化工行业的技术类期刊。

cultivation of internationalized talents

cultivation of internationalizedtalentsCultivation of internationalized talents refers to the process of developing individuals with global perspectives, cross-cultural competence, and the ability to thrive in an international environment. With the increasing globalization of the world, the demand for internationalized talents is rising rapidly in various fields. Here are some key aspects of cultivating internationalized talents: First of all, language proficiency is crucial for internationalized talents.A good command of one or more foreign languages enables them to communicate effectively with people from different countries and cultures. In addition to fluent verbal communication, proficiency in written and reading comprehension is also essential.Secondly, cross-cultural competence is another important aspect. Internationalized talents should have an understanding and appreciation of different cultures, and be able to adapt to and work effectively in multicultural environments. This includes knowledge of cultural nuances, customs, and business etiquette of different countries.Furthermore, global perspectives are indispensable for internationalized talents. They should be familiar with international trends, geopolitical landscapes, and economic dynamics. Keeping abreast of global events and understanding the interrelationships between countries and regions help them make informed decisions and contribute to global development.Moreover, leadership and teamwork skills are also crucial. Internationalized talents should possess the ability to lead and inspire teams composed of individuals from diverse backgrounds. Effective collaboration and communication within teams are essential for achieving common goals in an international context.In conclusion, the cultivation of internationalized talents requires acomprehensive approach that encompasses language proficiency, cross-cultural competence, global perspectives, and leadership skills. By developing these qualities, individuals can become competent global citizens and contribute to the international community in various fields.。

NIBSC-WHO AFP标准物质

WHO International StandardAlphafoetoprotein, Human, 100,000 IUNIBSC code: AFPInstructions for use(Version 6.0, Dated 11/12/2012)1. INTENDED USEThis material was prepared from a pool of several hundred cord sera characterised by the Statens Serum Institut (SSI), Copenhagen, Denmark and it was established as the First WHO IS for AFP in 1975 (1). With effect from 1st July 1997, the National Institute for Biological Standards and Control (NIBSC), Potters Bar, UK became the custodian and distributor of this material.2. CAUTIONThis preparation is not for administration to humans.This preparation contains material of human origin. The ampouled material has been tested and found negative for HBsAg and anti-HIV. It gave a positive PCR test for HCV RNA. The preparation should be regarded as potentially hazardous to health. The container and its contents should be used and discarded according to your own laboratory procedures. Such procedures probably will include the wearing of protective gloves and avoiding the generation of aerosols. Care should be exercised in opening the container to avoid cuts3. UNITAGEEach ampoule of this preparation contains 100,000 International Units by definition (1,2,3).Uncertainty: the International unit of AFP is assigned without uncertainty. The uncertainty of the ampoule content of AFP may be considered to be the coefficient of variation, which was determined to be ± 0.42%.4. CONTENTSCountry of origin of biological material: DenmarkThe pool was distributed into ampoules in volumes of 2ml and freeze-dried. The ampoules were originally coded 72/225 and contain approx 70 mg of protein each.5. STORAGEUnopened ampoules should be stored, in the dark, at –20ºCPlease note: because of the inherent stability of lyophilized material, NIBSC may ship these materials at ambient temperature.6. DIRECTIONS FOR OPENINGTap the ampoule gently to collect the material at the bottom (labelled) end. Ensure ampoule is scored all round at the narrow part of the neck, with a diamond or tungsten carbide tipped glass knife file orother suitable implement before attemptingto open. Place theampoule in the ampoule opener, positioning the score at position 'A'; shown in the diagram below. Surround the ampoule with cloth or layers of tissue paper. Grip the ampoule and holder in the hand and squeeze at point 'B'. The ampoule will snap open. Take care to avoid cuts and projectile glass fragments that enter eyes. Take care that no material is lost from the ampoule and that no glass falls into the ampoule.Side view of ampoule opening device containing an ampoule positioned ready to open. 'A' is the score mark and 'B' the point of applied pressure.7. COLLABORATIVE STUDYThe standard preparation has been investigated in two collaborative studies (3,4) using several assay methods, such as radioimmunoassay, single radial immunodiffusion and immunoelectrophoresis. Six laboratories estimated that one IU approximately equals 1.21 (1.02 –1.43) nanograms of AFP (3).8. STABILITYThe total contents of an ampoule should be reconstituted in a suitable volume of the solvent to be used in the test. If 10ml of solvent is used, the resulting solution will have a concentration of 10,000 IU/ml. If not used shortly after reconstitution, the solution should be kept in a frozen state.It is the policy of WHO not to assign an expiry date to their international reference materials. They remain valid with the assigned potency and status until withdrawn or amended.Reference materials are held at NIBSC within assured, temperature-controlled storage facilities. Reference Materials should be stored on receipt as indicated on the label. For information specific to a particular biological standard, contact standards @.In addition, once reconstituted, diluted or aliquoted, users should determine the stability of the material according to their own method of preparation, storage and use.NIBSC follows the policy of WHO with respect to its reference materials.Users who have data supporting any deterioration in the characteristics of any reference preparation are encouraged to contact NIBSC.9. REFERENCES1. WHO Technical Report Series No.594,1976,142. Sizaret P, Anderson S G, The International Reference Preparation for alphafoetoprotein. J of Biol. Stand., 4, 149, 19763. Sizaret P et al, Equivalence between international units and mass units of alphafoetoprotein. Report of a collaborative study. Clinica Chimica Acta, 96, 59-65, 19794. Sizaret P, Breslow N, Anderson S G, and 12 other participants, Collaborative study of a preparation of human cord serum for its use as a reference in the assay of alphafoetoprotein, J Biol. Stand 3, 201-223, 197510. FURTHER INFORMATIONFurther information can be obtained as follows;This material: enquiries@WHO Biological Standards:http://www.who.int/biologicals/en/JCTLM Higher order reference materials:/en/committees/jc/jctlm/Derivation of International Units:/products/biological_reference_materials/frequently_ asked_questions/how_are_international_units.aspxOrdering standards from NIBSC:/products/ordering_information/frequently_asked_qu estions.aspxNIBSC Terms & Conditions:/terms_and_conditions.aspx11. CUSTOMER FEEDBACKCustomers are encouraged to provide feedback on the suitability or use of the material provided or other aspects of our service. Please send any comments to enquiries@12. CITATIONIn all publications, including data sheets, in which this material is referenced, it is important that the preparation's title, its status, the NIBSC code number, and the name and address of NIBSC are cited and cited correctly.14. LIABILITY AND LOSSIn the event that this document is translated into another language, the English language version shall prevail in the event of any inconsistencies between the documents.Unless expressly stated otherwise by NIBSC, NIBSC’s Standard Terms and Conditions for the Supply of Materials (available at /About_Us/Terms_and_Conditions.aspx or upon request by the Recipient) (“Conditions”) apply to the exclusion of all other terms and are hereby incorporated into this document by reference. The Recipient's attention is drawn in particular to the provisions of clause 11 of the Conditions.17. CERTIFICATE OF ANALYSISNIBSC does not provide a Certificate of Analysis for WHO Biological Reference Materials because they are internationally recognised primary reference materials fully described in the instructions for use. The reference materials are established according to the WHO Recommendations for the preparation, characterization and establishment of international and other biological reference standards http://www.who.int/bloodproducts/publications/TRS932Annex2_Inter_biol efstandardsrev2004.pdf (revised 2004). They are officially endorsed by the WHO Expert Committee on Biological Standardization (ECBS) based on the report of the international collaborative study which established their suitability for the intended use.。

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1 Introduction
Gene therapy has rapidly become an advancing field with enormous potential to treat different vital human diseases[1]. It is very important for successful gene therapy to develop potent gene transfer sysoreign gene efficiently and safely into target cells and region. The non-viral vector, with significantly low safety risk and convenient preparation, has been suggested as an alternative to viral vector [2]. Therefore, to develop a safe and effective nonviral vector system become urgent. Among non-viral vectors, cationic gene delivery
SONG Yuanjian1,2△, ZONG Zhimin1, LIU Hongzhi2△, WEN Xiangru2, QI Dashi2, DU Yang2, ZHANG Fang2, WEI Xianyong1*
(1. Key Laboratory of Coal Processing and Efﬁ cient Utilization (Ministry of Education), China University of Mining & Technology, Xuzhou 221008, China;2. Department of Neurobiology, Xuzhou Medical College, Xuzhou 221002, China) Abstract: Cationic nanoparticles (NPs) for gene delivery were successfully prepared by assembling carboxylation poly(lactic-co-glycolic acid) (PLGA), polyethylene glycol (PEG), L-α-Phosphatidylethanolamine (DOPE) and octadecyl quaternized carboxymethyl chitosans (OQCMC). Lactoferrin (Lf) was selected as a targeting ligand conjugated to PLGA via bifunctional PEG, yielding PLGA-PEG-Lf/DOPE NPs to be used for gene vectors. Fourier transform infrared spectroscopy (FTIR), UV and nuclear magnetic resonance (NMR) spectroscopy were performed to evaluate the synthesis of the vectors. The characteristics of the vectors loaded heme oxygenase (HO-1) gene were evaluated by transmission electron microscope (TEM), particle size analyser and ﬂuorescent microscopy. The experimental results showed that the obtained vectors were spherical in shape with average particle size of 142.2 nm and zeta potentials of +16.4 mV. The vectors could protect the loaded gene from the degradation by nuclease. For 293T cells, there is high transfection efﬁciency of the vectors similar to liposome-2000. It can be concluded that the established cationic PLGA-PEG-Lf/DOPE NPs have potential gene delivery ability for gene therapy. Key words: PLGA nanoparticles; PEGylation; gene delivery; lactoferrin
©Wuhan University of Technology and SpringerVerlag Berlin Heidelberg 2012 (Received: Sep. 12, 2011; Accepted: Dec. 10, 2011) SONG Yuanjian(宋远见): E-mail:biosongyuanjian@ *Corresponding author: WEI Xianyong(魏贤勇): Prof.; Ph D; E-mail: wei_xianyong@ △These authors contributed equally to this work Funded by the Natural Science Foundation of China for Innovative Research Group(50921002), the National Natural Science Foundation of China (30800446, 31100762), the Education Departmental Natural Science Research Funds of Jiangsu Provincial Higher School of China (09KJB310016), the Science and Technology Planning Project of Xuzhou (xzzd1054), the Special Foundation of President of Xuzhou Medical College (2010KJZ27), and the Priority Acedemic Program Development of Jiangsu Higher Education Institutions
polymers include poly(ethylenimine) (pEI), chitosan, poly(2-dimethylaminoethyl methacrylate), and polyL-lysine (pLL) have been studied a lot[3,4]. However, there are also some drawbacks for these polymers, such as bad degradable property, low biocompatibility and high cytotoxicity[5]. Consequently, there is a need for biodegradable gene delivery systems. Moreover, the degradation of the polymer can be used as a tool to release the plasmid DNA into the cytosol. Recently, the use of nanoparticles prepared with biocompatible and biodegradable poly(lactic-co-glycolic acid) (PLGA) polymer has attracted much attention due to their excellent physicochemical characteristics in terms of safety, stability, the relative ease of large-scale production, and low immunogenicity[6, 7]. Although PLGA nanoparticles might be a promising and suitable candidate for gene delivery application[8, 9], there also exist several drawbacks[10]. The key problem is that low DNA encapsulation or adsorption ratio due to its negative electricity surface. The other is that PLGA nanoparticles tend to bind serum protein in systemic application due to the hydrophobic surface, which can lead to opsonization and clearance by the reticuloendothelial system (RES). Therefore, it is necessary to treat the surface property of PLGA NPs systems by modiﬁcation to PLGA or by
Journal of Wuhan University of DOI 10.1007/s11595-012-0440-4