A COURSE ON THEORY OF CHARGED POLYMERS 课堂讲义 References

分类综合练习：阅读理解 + 阅读七选五 + 完形填空（十五）--2022届高考英语复习备考阅读理解阅读下列短文，从每题所给的A、B、C和D四个选项中，选出最佳选项。

The online business model is changing on a satisfaction-first basis. It doesn’t matter if someone recommended you an app，nothing beats getting to try out the app first before deciding on whether or not to apply for the service.● RhapsodyListen to Rhapsody’s large music library and get the option to download and listen to songs or even full-length al bums when you’re offline. At the moment，this service is available in 32 countries only. Remember that you’ll need to cancel within the free trial period to avoid being charged for your first month.[Trial period—14 days | After trial—$9.99/month | Try now]● BitstockNeed to save photos for your presentations and artworks？Go to Bitstock to check out their collection from top artists and photographers around the world. Choose from over 30 million photos，and illustrations （插圖），with 75，000 images coming in every new week. All you need to start your free trial is your email address.[Trial period—7 days | After trial—$79/month | Try now]● CanvasIf you are drowning in paperwork，perhaps it is time to use Canvas and transfer all your paperwork online. Digitalize your work orders，forms etc. so that they can be filled up and completed right on any mobile device. This makes it easy to create，edit，gain valuable data and send it to the people who need it in seconds.[Trial period—30 days | After trial—$13/month | Try now]● BackupifyIf you have ever lost your phone，you know how important it is to backup （备份）all your important documents，notes，contacts and other personal details. Get cloud-to-cloud protection of up to 3 PB of data with Backupify. You can back up your data for Google apps，Office 365，various social media sites and even Salesforce.[Trial period—15 days | after trial—$3/month | Try now]To learn more about the Apps above，Click Here.1. Who is more likely to use the app Canvas？A. A secretary.B. A photographer.C. An artist.D. A musician.2. What can be of some help to save photos？A. Bigstock and Canvas.B. Backupify and Bigstock.C. Rhapsody and Backupify.D. Rhapsody and Canvas.3. What do the four apps have in common？A. They offer free entertainment services.B. Users will access them via email accounts.C. They can help improve users work skills.D. Users can try them without paying money.It was graduation day at the university where I work and a beautiful day quite unlike the first graduation I attended as a young professor. On that cold day years ago，as we watched the students walking into the hall，one of my colleague turned to me and said，“Graduation will be one of the happiest and one of the saddest time of your life.” At my inquiry，he answered，“Because the students you have gotten to know have to leave.”As years went by，my previous confusion about my colleagues words no longer existed. When I came across naughty students，I have had to rethink why I chose to be a teacher. It obviously isn’t the money. Once a former computer science student of mine called me，asking me if I wanted to have a change. He was working at Nintendo Corporation. His salary was higher than my current one，though I have more education and have worked for over a decade. With my programming skills，he said he could get me hired. I thanked him，but declined his kind offer.A few days before this current graduation，while working on final grades，I found a note a student had slipped in with her homework. She thanked me for being her teacher and said the things she had learned in my class—not about math，but about life—would be things she would remember long afterthe math skills had faded away. As I finished reading，I remembered why I had become a teacher.Now，on this sunny graduation day，as I again observed the sea of blue hats and gowns，I did so with renewed dedication and a deeper sense of satisfaction—I will always be grateful that I am a teacher.4. How did the author feel when he heard his colleague talking about graduation for the first time？A. Satisfied.B. Puzzled.C. Shocked.D. Sad.5. The computer science student called up the author ___ .A. to inform the author of his present jobB. to persuade the author to work with himC. to thank the author for being his teacherD. to share his joy and satisfaction with the author6. What does the underlined part “blue hats and gowns” in the last paragraph refer to？A. School life memories.B. Graduates clothes.C. Graduation ceremonies.D. Decorations in the hall.7. What is the authors purpose of writing the text？A. To express his devotion to teaching.B. To talk about the meaning of graduation.C. To give advice on how to be a good teacher.D. To compare two different graduation ceremonies.The meaning of silence varies among cultural groups. Silences may be thoughtful，or they may be empty when a person has nothing to say. A silence in a conversation may also show stubbornness，or worry. Silence may be viewed by some cultural groups as extremely uncomfortable; therefore attempts may be made to fill every gap with conversation. Persons in other cultural groups value silence and view it as necessary for understanding a person’s needs.Many Native Americans value silence and feel it is a basic part of communication among people，just as some traditional Chinese and Thaipersons do. Therefore，when a person from one of these cultures is speaking and suddenly stops，what maybe implied （暗示）is that the person wants the listener to consider what has been said before continuing. In these cultures，silence is a call for reflection.Other cultures may use silence in other ways，particularly when dealing with conflicts among people or in relationships of people with different amounts of power. For example，Russian，French，and Spanish persons may use silence to show agreement between parties about the topic under discussion. However，Mexicans may use silence when instructions are given by a person in authority rather than be rude to that person by arguing with him or her. In still another use，persons in Asian cultures may view silence as a sign of respect，particularly to an elder or a person in authority.Nurses and other care-givers need to be aware of the possible meanings of silence when they come across the personal anxiety their patients may be experiencing. Nurses should recognize their own personal and cultural construction of silence so that a patients silence is not interrupted too early or allowed to go on unnecessarily. A nurse who understands the healing value of silence can use this understanding to assist in the care of patients from their own and from other cultures.8. What does the author say about silence in conversations？A. It implies rudeness.B. It promotes friendship.C. It is culture-specific.D. It is content-based.9. Who might regard silence as a call for careful thought？A. The Chinese.B. The French.C. The Mexicans.D. The Russians.10. What does the author advise nurses to do about silence？A. Let it continue as the patient pleases.B. Break it while treating patients.C. Evaluate its harm to patients.D. Make use of its healing effects.11. What can be the best title for the text？A. Sound and SilenceB. What It Means to Be SilentC. Silence to Native AmericansD. Speech Is Silver; Silence Is GoldThe batteries of the future may be made of paper. Researchers at Binghamton University，State University of New York have created a biodegradable （能生物降解的），paper-based battery that is more efficient than previously possible.For years，there has been excitement in the scientific community about the possibility of paper-based batteries as an eco-friendly alternative. However，the proposed designs were never quite powerful enough，they were difficult to produce and it was questionable whether they were really biodegradable.This new design solves all of those problems. Associate Professor Seokheun “Sean” Choi from the Electrical and Computer Engineering Department and Professor Omowunmi Sadie from the Chemistry Department worked on the project together. Choi engineered the design of thepaper-based battery，while Sadie was able to make the battery aself-sustaining bio battery. “There’s been a dramatic increase in electronic waste and this may be an excellent way to start reducing that，” said Choi. “Our hybrid paper battery exhibited a much higher power-to-cost ratio （比率）than all previously reported paper-based batteries powered by bacteria.”The bio battery uses a hybrid of paper and engineered polymers （聚合物）—were the key to giving the batteries biodegrading properties. The team tested the degradation of the battery in water and it clearly biodegraded without the requirements of special facilities，conditions or introduction of other microorganisms.The polymer-paper structures are lightweight and flexible. Choi said that flexibility also provided another benefit. “Power enhancement can be potentially achieved by simply folding or piling the flexible paper-polymer batteries，” said Choi.The team said that producing the biobatteries is a fairly straightforward process and that the material allows for changes depending on what structure or shape is needed.The work was supported by a grant from the National Science Foundation and done through the Center for Research in Advanced Sensing Technologies and Environmental Sustainability （CRASTES）.12. What is a problem of the previously proposed designs？A. They are too expensive.B. They aren’t really biodegradable.C. There is no easy way to produce them.D. It is extremely difficult to charge them.13. What advantage did Choi mention of the newly invented battery in paragraph 3？A. Its lower cost-to-power ratio.B. Its function of reducing water pollution.C. Its larger surface area.D. Its new organization of bacteria.14. What can we know about the degradation of the bio battery？A. It goes the best in pure water.B. It requires no special conditions.C. It results in a harmful state of soil.D. It relies mainly on the paper in the battery.15. What does the underlined word “enhancement” in Paragraph 5 probably mean？A. Produce.B. Reserve.C. Flow.D. Increase.1—5 ABDBB 6—10 BACAD 11—15 BCABD阅读七选五根据短文内容，从短文后的选项中选出能填入空白处的最佳选项。

Note:Within nine months from the publication of the mention of the grant of the European patent,any person may give notice to the European Patent Office of opposition to the European patent granted.Notice of opposition shall be filed in a written reasoned statement.It shall not be deemed to have been filed until the opposition fee has been paid.(Art.99(1) European Patent Convention).Europäisches PatentamtEuropean Patent OfficeOffice européen des brevets(19)5 10 15 20 25 30 35 40 45 50 55DescriptionField of the Invention[0001]The invention relates generally to the field of capillary electrophoresis,and more particularly to materials and methods for suppressing electroendoosmotic flow and analyte-wall interactions during separation of biomolecules, especially polynucleotides, by capillary electrophoresis.Background[0002]Capillary electrophoresis has been applied widely as an analytical technique because of several technical advantages:(i)capillaries have high surface-to-volume ratios which permit more efficient heat dissipation which,in turn,permit high electric fields to be used for more rapid separations;(ii)the technique requires minimal sample vol-umes;(iii)superior resolution of most analytes is attainable;and(iv)the technique is amenable to automation,e.g. Camilleri,editor,Capillary Electrophoresis:Theory and Practice(CRC Press,Boca Raton,1993);and Grossman et al,editors,Capillary Electrophoresis(Academic Press,San Diego,1992).Because of these advantages,there has been great interest in applying capillary electrophoresis to the separation of biomolecules,particularly in nucleic acid analysis.The need for rapid and accurate separation of nucleic acids,particularly deoxyribonucleic acid(DNA)arises in the analysis of polymerase chain reaction(PCR)products and DNA sequencing fragment analysis,e.g.Williams, Methods4:227-232(19920;Drossman et al,Anal.Chem.,62:900-903(1990);Huang et al,Anal.Chem.,64:2149-2154 (1992); and Swerdlow et al, Nucleic Acids Research, 18: 1415-1419 (1990).[0003]Since the charge-to-frictional drag ratio is the same for different sized polynucleotides in free solution,elec-trophoretic separation requires the presence of a sieving medium.The initial sieving media of choice were gels,but problems of stability and manufacturability have led to the examination of non-gel liquid polymeric sieving media,such as linear polyacrylamide,hydroxyalkylcellulose,agarose,and cellulose acetate,and the like,e.g.Bode,Anal.Biochem., 83:204-210(1977);Bode,Anal.Biochem.,83:364-371(1977);Bode,Anal.Biochem.,92:99-110(1979);Hjerten et al,J.Liquid Chromatography,12:2471-2477(1989);Grossman,U.S.patent5,126,021;Zhu et al,U.S.patent5,089111; Tietz et al, Electrophoresis, 13: 614-616(1992).[0004]Another factor that complicates separations by capillary electrophoresis is the phenomena of electroendoos-mosis.This phenomena,sometimes referred to as electroosmosis,is fluid flow in a capillary induced by an electrical field.It has impeded the application of capillary electrophoresis to situations where high resolution separations are required,such as in the analysis of DNA sequencing fragments.The phenomena arises in capillary electrophoresis when the inner wall of the capillary contains immobilized charges which cause the formation of a mobile layer of counter ions which,in turn,moves in the presence of an electrical field to create a bulk flow of liquid.Unfortunately,the magnitude of the electroendoosmotic flow can vary depending on a host of factors,including variation in the distribution of charges, selective adsorption of components of the analyte and/or separation medium,pH of the separation medium,and the like.Because this variability tends to reduce ones ability to resolve closely spaced bands analyte,many attempts have been made to directly or indirectly control such flow.The attempts have included covalent modification of the inner wall of the capillary to suppress charged groups,use of high viscosity polymers,adjustment of buffer pH and/or concen-tration,use of a gel separation medium covalently attached to the capillary wall,and the application of an electric field radial to the axis of the capillary,e.g.Hayes et al,Anal.Chem.,65:2010-2013(1993);Drossman et al(cited above); Hjerten,U.S.patent4,680,201;Van Alstine et al,U.S.patent4,690,749;Wiktorowicz et al,Electrophoresis,11:769-773 (1990); Belder et al, J. High Resolution Chromatography, 15: 686-693 (1992).[0005]Most of these approaches have met with mixed success or have only been used in the separation of analytes quite different chemically from nucleic acids.In particular,the use of capillary gels for DNA separations have been hampered by manufacturing problems and problems of stability and reliability during use,e.g.Swerdlow et al,Electro-phoresis, 13: 475-483 (1992).[0006]In view of the strong scientific and industrial interest in being able to conveniently and accurately separate a variety of biomolecules,particularly polynucleotides,it would be desirable to have available a low viscosity electro-phoretic separation medium capable of suppressing electroendoosmotic flow and of reducing analyte-wall interactions.Summary of the Invention[0007]The invention relates to the use of uncharged water-soluble silica-adsorbing polymers to suppress electro-endoosmotic flow and to reduce analyte-wall interactions in capillary electrophoresis.In one aspect of the invention, one or more of such polymers are employed as components of a separation medium for the separation of biomolecules, preferably polynucleotides,by capillary electrophoresis.Generally,such polymers are characterized by(i)water sol-ubility over the temperature range between about20°C to about50°C,(ii)concentration in a separation medium in the5 10 15 20 25 30 35 40 45 50 55range between about0.001%to about10%(weight/volume),(iii)molecular weight in the range of about5x103to about1x106daltons,and(iv)absence of charged groups in an aqueous medium having pH in the range of about6 to about9.Preferably,such polymers of the invention are substantially non-hydroxylic.In one embodiment,polymers of the invention are selected from the group consisting of polyvinylactams,such as polyvinylpyrrolidone;N,N-disubsti-tuted polyacrylamides;and N-substituted polyacrylamides.More preferably,such polymers of the invention are poly (N,N-dimethylacrylamide).[0008]In accordance with the method of the invention,a sufficient amount of polymer adsorbs to the silica surface to establish a zone of high viscosity at the silica surface that impedes the movement of an electrical double layer under an electric field and that shields the analyte from the wall.[0009]The invention includes methods of using the polymers of the invention to separate biomolecules,especially polynucleotides,by capillary electrophoresis;compositions comprising polymers of the invention for electrophoretically separating biomolecules in capillaries;and methods of using the separation medium of the invention for sequencing DNA.[0010]The invention enhances the precision of biomolecule separation by electrophoresis in a capillary by dynam-ically suppressing electroendoosmotic flow and wall-analyte interactions through the adsorption of the uncharged pol-ymers of the invention onto the surface of the capillary.Suppression is dynamic in the sense that throughout the sep-aration process polymers of the invention adsorb and desorb from the surface of a capillary in equilibrium with polymer in solution in the separation medium.Thus,a constant degree of suppression is maintained not only during a separation run, but also from separation run to separation run.Brief Description of the Figures[0011]Figure 1 diagrammatically illustrates an apparatus for carrying out capillary electrophoresis.Figure2is an electropherogram of a100basepair DNA ladder separated in a3%poly(dimethyacrylamide)solution (RM8) in a glycylglycine buffer.Figure3is an electropherogram of a100basepair DNA ladder separated in a3%poly(dimethyacrylamide)solution (RM18) in a glycylglycine buffer.Figure4is an electropherogram of a100basepair DNA ladder separated in a3%poly(dimethyacrylamide)solution (RM18) in a TBE buffer.Figure5is an electropherogram of a100basepair DNA ladder separated in a binary polymer solution comprising 3% polyacrylamide and 0.05% poly(dimethylacrylamide) (RM18) in a glycylglycine buffer.Figures6A to6F are electropherograms of a100basepair DNA ladder separated in various binary polymer solu-tions.Figures7A to7J is an electropherogram of a commercially available DNA sequencing fragment standard separated in a separation medium containing a 6.5% solution of poly(dimethylacrylamide).Figure8is an electropherogram showing the separation and sequencing of a4-color sequencing standard in a separation medium containing a6.5%solution of poly(dimethylacrylamide).The numbers above the peaks refer to the base number in the sequence, and the letters above each peak refer to the identity of the base.Figure 9 is an electropherogram showing a 4-color DNA sequencing analysis in Polyvinylpyrrolidone. Definitions[0012]The term"capillary"as used herein refers to a tube or channel or other structure capable of supporting a volume of separation medium for carrying out electrophoresis.The geometry of a capillary may vary widely and includes tubes with circular,rectangular or square cross-sections,channels,groves,plates,and the like,and may be fabricated by a wide range of technologies.An important feature of a capillary for use with the invention is the surface-to-volume ratio of the surface in contact with the volume of separation medium.High values of this ratio permit better heat transfer from the separation medium during electrophoresis.Preferably,values in the range of about0.4to.04are employed. These correspond to the surface-to-volume ratios of tubular capillaries with circular cross-sections having inside di-ameters in the range of about10µm to about100µm.Preferably,capillaries for use with the invention are made of silica,fused silica,quartz,silicate-based glass,such as borosilicate glass,phosphate glass,alumina-containing glass, and the like, or other silica-like materials.[0013]The term"biomolecule"means a molecule typically synthesized by a biological organism that is water soluble and charged in the pH range of from about6to about9.Preferably,the term biomolecule includes proteins,glycopro-teins,natural and synthetic peptides,alkaloids,polysaccharides,polynucleotides,and the like.More preferably,the term biomolecule refers to polynucleotides.5 10 15 20 25 30 35 40 45 50 55[0014]The term"polynucleotide"as used herein refers to linear polymers of natural or modified nucleoside mono-mers,including double and single stranded deoxyribonucleosides,ribonucleosides,α-anomeric forms thereof,and the ually the nucleoside monomers are linked by phosphodiester bonds or analogs thereof to form polynucleotides ranging in size from a few monomeric units,e.g.8-40,to several thousands of monomeric units.Whenever a polynu-cleotide is represented by a sequence of letters,such as"ATGCCTG,"it will be understood that the nucleotides are in 5'->3'order from left to right and that"A"denotes deoxyadenosine,"C"denotes deoxycytidine,"G"denotes deoxygua-nosine,and"T"denotes thymidine,unless otherwise noted.Analogs of phosphodiester linkages include phospho-rothioate,phosphorodithioate,phosphoroselenoate,phosphorodiselenoate,phosphoroanilothioate,phosphoranili-date, phosphoramidate, and the like.[0015]As used herein,"nucleoside"includes the natural nucleosides,including2'-deoxy and2'-hydroxyl forms,e.g.as described in Kornberg and Baker,DNA Replication,2nd Ed.(Freeman,San Francisco,1992)."Analogs"in ref-erence to nucleosides includes synthetic nucleosides having modified base moieties and/or modified sugar moieties, e.g. described generally by Scheit, Nucleotide Analogs (John Wiley, New York, 1980).[0016]The term"electroendoosmosis"or"electroendoosmostic flow"as used herein refers to the bulk flow of liquid due to the influence of an electric field on the layer of mobile counter ions adjacent to fixed,or immobile,charges on a surface,such as a capillary wall.Electroendoosmotic flow is typically measured as the mobility(cm2/sec-volts)of a test analyte through a capillary tube under a standard set of conditions,e.g.determining buffer concentration and type, tube length, electrical field strength, and the like.[0017]The term"polymer"is a large molecule composed of smaller monomeric subunits covalently linked together in a characteristic fashion.A"homopolymer"is a polymer made up of only one kind of monomeric subunit.A"copolymer" refers to a polymer made up of two or more kinds of monomeric subunits.As used herein the term"polymer"includes homopolymers and copolymers.A"monodisperse"polymer solution means that the polymer molecules in solution have substantially identical molecular weights.A"polydisperse"polymer solution means that the polymer molecules in solution have a distribution of molecular weights.[0018]The term"non-hydroxylic"as used herein in reference to polymers means that the monomers used in the synthesis of a polymer contain no hydroxyl substituents.Detailed Description of the Invention[0019]The invention provides a convenient means for suppressing electroendoosmotic flow and wall-analyte inter-actions during the separation of biomolecules,particularly DNA,by capillary electrophoresis.As used herein,the term "separation medium"refers to the medium in a capillary in which the separation of analyte components takes place. Separation media typically comprise several components,at least one of which is a charge-carrying component,or electrolyte.The charge-carrying component is usually part of a buffer system for maintaining the separation medium at a constant pH.Media for separating polynucleotides,or other biomolecules having different sizes but identical charge-frictional drag ratios in free solution,further include a sieving component.In addition to such conventional components,the separation medium of the invention comprise a surface interaction component.In the case of poly-nucleotide separations,the sieving component may be the same or different than the surface interaction component, but is usually different.The surface interaction component comprises one or more uncharged water-soluble silica-adsorbing polymers having the physical properties set forth above.Preferably,such one or more uncharged water-soluble silica-adsorbing polymers are non-hydroxylic.In further preference for polynucleotide separations,the sieving component of the separation medium of the invention comprises one or more uncrosslinked,particularly linear,poly-mers.Preferably,the components of the separation medium of the invention are selected so that its viscosity is low enough to permit rapid re-filling of capillaries between separation runs.For typical capillaries,e.g.20-100µm inside diameter and40-60cm in length,in the absence of a sieving component,viscosity is preferably less than1000 centipoise,and more preferably,between about1to about300centipoise.In the presence of a sieving component, viscosity is preferably less than 5000 centipoise, and more preferably, less than 1000 centipoise.[0020]Polymers for use as the surface interaction component of the separation medium may belong to a variety of chemical classes,such as those described in the following references:Molyneux,Water-Soluble Synthetic Polymers: Properties and Behavior,Volumes I and II(CRC Press,Boca Raton,1982);Davidson,Editor,Handbook of Water-Soluble Gums and Resins(McGraw-Hill,New York,1980);Franks,editor,Water:A Comprehensive Treatise(Plenum Press,New York,1973);and the like.Preferably,the uncharged water-soluble silica-adsorbing polymers of the invention include,but not limited to,N,N-disubstituted polyacrylamides,N-monosubstituted polyacrylamides,polymethacryla-mide,polyvinylpyrrolidone,and the like.Exemplary substituents of the polyacrylamides include C1to C12alkyl;halo-substituted C1to C12alkyl;methoxy-substituted C1to C12alkyl;hydroxyl-substituted C1to C12alkyl and the like. Preferably,the halo substituent is fluoro and the hydroxyl-substituted C1to C12alkyl is monosubstituted.It is understood that the above monomer substituents are selected so that the resulting polymer is water soluble.For example,it is clear that C12alkyl-containing mononer could only be present as a small fractional component of a copolymer.More5 10 15 20 25 30 35 40 45 50 55preferably,exemplary substituents are selected from the group consisting of C1to C3alkyl;halo-substituted C1to C3 alkyl; methoxy-substituted C1 to C3 alkyl; and hydroxyl-substituted C1 to C3 alkyl.[0021]Such polymers are synthesized by conventional techniques,e.g.as disclosed in Odian,Principles of Polym-erization,Third Edition(John Wiley,New York,1991).An important feature of the invention is that the polymer of the surface interaction component be uncharged.Preferably,polymers of the invention are synthesized under non-aqueous conditions so that uncharged initiators can be used.Such conditions also preclude the incorporation of charged initiators into the product.The polymers comprising the surface interaction component of the separation medium may be present at a concentration of from about.001%to about10%(w:v).Preferably,such polymers are present at a concentration in the range of about.01% to about 6%.[0022]The silica-adsorbing quality of the preferred polymers can be measured in a number of well-known ways, such as by ellipsometry,determining changes in the hydrodynamic properties of adsorbent test particles,determination of adsorption isotherms,or like methods.Such techniques are described in Malmsten et al,Macromolecules,25: 2474-2481(1992);Rob and Smith,European Polymer J.,10:1005-1010(1974);Vincent et al Surf.Colloid Sci.,12: 1-117(1982);Takahashi et al,Advances in Polymers Science,46:1-65(1982),and like references.An adsorption isotherm is a graphical presentation of the adsorption exerted by an adsorbent on a solution of a given substance at a fixed temperature.The determination of adsorption isotherms require the preparation of solutions of known concen-trations of the material whose adsorption is to be measured(the adsorbate).The adsorbate solutions are combined with known quantities of the material(the adsorbent)whose surface the adsorbate adheres to.Once an equilibrium is reached between the adsorbate in solution and the adsorbate on the surface of the adsorbent,the concentration of the adsorbate solution is determined.The reduction in concentration of the solution is a measure of the degree of adsorption of the adsorbate under the standard conditions.[0023]The degree of adsorption may also be measured indirectly by observing the reduction of electroendoosmotic flow under a set of standard values of the following parameters:buffer type and concentration,temperature,electric field strength,capillary type,diameter,and length,and test analyte.An exemplary standard for such measurement is as follows:Uncoated fused silica capillary40cm in total length,20cm to detector(UV),75µm inside diameter;0.1M glycylglycine buffer(pH8.0);marker solution of0.92mM mesityl oxide and1mM p-toluenesulfonic acid(p-TSA); electrophoresis at30°C under10kV.The polymer being tested is added to the buffer.With no surface interaction component,the electroendoosmotic flow is approximately6x10-4cm2/sec-volts.Preferably,in such a separation medium,a sufficient concentration of polymer of the invention is employed to reduce electroendoosmotic flow to less than about 2 x 10-5 cm2/sec-volts.[0024]For polynucleotide separations,the silica-adsorbing quality of a polymer of the invention is preferably char-acterized by the relationship between resolving power and polynucleotide length for a selected"ladder"of polynucle-otides under a standard set of conditions.Resolving power is conveniently expressed in terms of the number of theo-retical plates,N,of the test system.N=(L/σ)2where L is the average path length of a test analyte under a peak from injection port to detector(usually position of peak maximum)andσis the variance of the peak.Preferably,polymers of the invention provide a substantially linear relationship between number of theoretical plates and size of polynucle-otide over the range of from about100to about500nucleotides;more preferably,the relationship is linear over the range of from about20to about600nucleotides.A standard set of conditions for generating theoretical plates versus polynucleotide length curves is described below.[0025]Exemplary ladders of different-sized polynucleotides in the above-mentioned size ranges are available in commercially available kits,e.g.the100basepair double stranded DNA ladder from BRL-GIBCO,the Taq DNA Se-quencing Standard from Applied Biosystems,Inc.,or the like.A standard separation medium can be prepared as follows:0.60g of acrylamide(ultrapure,ICN,Costa Mesa,CA)is dissolved in10ml1x TBE,30%formamide,3.5M urea buffer,filtered(0.2µm pore size),and degassed.The monomer solutions are polymerized by addition at room temperature of1µl of100%N,N,N',N'-tetramethylethylenediamine(TEMED)and2µl ammonium persulfate,10%w: v in water(APS),per ml of monomer solution(to give a final concentration of0.02%w:v APS and0.1%v:v TEMED). [0026]The above separation medium is loaded into a55cm uncoated fused silica capillary tube,50µm inside diameter,40cm to detector.The capillary may be used in a commercially available capillary electrophoresis apparatus having fluorescence detection capability.Fluorescence detection systems for detecting fluorescently labelled analytes in capillaries is well known in the art,e.g.Mathies et al,U.S.patent5,091,652;Mathies et al,International Application No.PCT/US93/01607;Ruiz-Martinez et al,Anal.Chem.65:2851-2858(1993);and the like.The DNA fragments from the standard are denatured and loaded electrokinetically as follows:The dried sample is resuspended in a mixture of 5mM aqueous EDTA(0.5µl)and formamide(6µl).The suspension is heated at90°C for2minutes then transferred to an ice bath.The ladder is loaded by placing the cathode and cathodic end of the capillary into the above solution then applying6kV across the tube for5seconds.Separation of the DNA fragments in the ladder commences by returning the cathode and cathodic end of the capillary into the cathode reservoir and applying a running voltage of12 kV.[0027]Apparatus for carrying out capillary electrophoresis is well-known and is not a critical feature of the invention.5 10 15 20 25 30 35 40 45 50 55Many references are available describing the basic apparatus and several capillary electrophoresis instruments are commercially available,e.g.Applied Biosystems(Foster City,CA)model270A instrument.Exemplary references de-scribing capillary electrophoresis apparatus and their operation include Jorgenson,Methods,4:179-190(1992);Col-burn et al,Applied Biosystems Research News,issue1(winter1990);Grossman et al(cited above);and the like. Figure1is a schematic representation of an exemplary capillary electrophoresis system20suitable for practicing the invention.However,as mentioned above,a wide variety of systems are amenable for use with the invention in addition to that represented in the figure,e.g.as described in Harrison et al,Science,261:895-897(1993);Pace,U.S.patent 4,908,112;Kambara et al,U.S.patent5,192,412;Seiler et al,Anal.Chem.,65:1481-1488(1993);and the like.In the figure,capillary tube22preferably has a length between about10to200cm,typically less than about100cm,and a preferred inner diameter in the range of about10to200µm,and more typically in the range of about50to75µm,e.g.available from Polymicro Technologies(Phoeniz,AZ).Preferably,there is no coating on the inside surface of the tube.A cathodic reservoir26in system20contains a separation medium28,described further below.The cathodic end22a of capillary tube22is sealed within reservoir26and is immersed in the separation medium during electro-phoresis.Second tube30in reservoir26is connected to a finely controlled air pressure system which can be used to control the pressure in the head space above the separation medium,e.g.for loading separation medium into the capillary tube by positive pressure.Sample reservoir31contains the sample mixture to be loaded into the cathodic end of capillary22.The anodic end22b of capillary22is immersed in separation medium32contained in anodic reservoir34.A second tube36in reservoir34can be included to control the pressure above separation medium32. High voltage supply40is connected to the cathodic and anodic reservoirs by electrodes41and42.High voltage supply 40produces a constant potential across the electrodes in the range of a few kilovolts(kV)to60kV,with a potential in the range of about10to30kV being typical.Currents through the capillary are generally in the microamp range, typically between a few to100µA,with20µA being typical.Detector44positioned adjacent to capillary22monitors sample peaks migrating through optical detection zone45of the capillary.Typically,optical detection zone45comprises a region of capillary22in which the ususal polyimide coating has been removed to permit UV and/or visible light,e.g. fluorescence,detection of the separated analyte.A wide variety of detection schemes are amenable for use with the invention,including UV absorption,fluorescence emission,conductance,radioactive emission,and the like.For ex-ample,detection systems for fluorescent analytes are described in Zare et al,U.S.patent4,675,300and Folestad et al, U.S. patent 4,548,498.[0028]As mentioned above,separation medium of the invention generally comprises.three components:a charge-carrying component,a sieving component,and a surface interaction component.Additional components may also be included in particular embodiments,such as denaturants when it is desirable to prevent the formation of duplexes or secondary structures in polynucleotides.Preferred denaturants include formamide,e.g.40-90%,urea,e.g.6-8M, commercially available lactams,such as pyrrolidone,and the like.Guidance for their use in electrophoresis can be found in well known molecular biology references,e.g.Sambrook et al,Molecular Cloning:A Laboratory Manual,Sec-ond Edition (Cold Spring Harbor Laboratory, New York, 1989).[0029]Typically,a buffer system for controlling pH is employed as the charge-carrying component.Exemplary buffers include aqueous solutions of organic acids,such as citric,acetic,or formic acid;zwitterionics,such as TES(N-tris [hydroxymethyl]-2-aminoethanesulfonic acid,BICINE(N,N-bis[2-hydroxyethyl]glycine,ACES(2-[2-amino-2-oxoethyl)-amino]ethanesulfonic acid),or glycylglycine;inorganic acids,such as phosphoric;and organic bases,such as Tris (Tris[hydroxymethyl]aminomethane)buffers,e.g.available from Sigma.Buffer concentration can vary widely,for ex-ample between about1mM to1M,but are typically about20mM.Exemplary buffer solutions for conventional capillary electrophoresis applications include the following:(i)0.1M Tris,0.25M boric acid,7M urea with a pH of7.6for single stranded polynucleotide separations;or(ii)0.089M Tris,0.089M boric acid,0.005M EDTA for double stranded poly-nucleotide separations.For non-zwitterionic buffer systems,preferably PDMA or polyvinylpyrrolidone are employed as the surface interaction component.[0030]Sieving components of electrophoretic separation media are well known in the art and are disclosed in Zhu et al,U.S.patent5,089,111;Ruiz-Martinez et al,Anal.Chem.,65:2851-2858(1993);Williams,Methods,4:227-232 (1992);and like references.Preferably,the sieving component of the separation medium of the invention is a low-viscosity entangled polymer solution as taught by Grossman,U.S.patent5,126,021.A low viscosity separation medium is preferred so that capillaries can be readily re-filled in automated systems,e.g.for large-scale DNA sequencing applications.The rate of solution flow through the capillary determines how much time is required to replace the sep-aration medium between successive analyses.Guidance for synthesizing entangled polymers with a range of viscos-ities suitable for DNA sieving applications is provided by Grossman,which is incorporated by reference.Generally,the viscosity of a polymer,or copolymer,solution is determined by the molecular weight(MW)and concentration of the polymer or copolymer components of the separation medium.The molecular weight of a polymer or copolymer can be adjusted during synthesis in a number of ways well known in the art,e.g.as reviewed in Odian,Principles of Polym-erization, Third Edition (John Wiley, New York, 1991), or like references.[0031]A second approach for controlling the average MW of a polymer or copolymer used in the invention is by。

● Portable TV, pickup camera, radio and tape recorder.●电动工具、割草机、吸尘器。

●Electric tool, field mower. Vacuum cleaner.●照相机、新闻摄影设备。

●Camera, news photography equipment.●便携式个人计算机、语言处理器、终端。

●Portable personal computer, language processor, terminal.●野外测试设备、医疗仪器设备。

●Outdoor testing equipment, medical instrument equipment.●移动电话机、对讲机。

●Mobile phone, walkie-talkie.●矿灯、割胶灯、应急灯、铁路信号灯。

●Lamp, tapping lamp, emergency light, railway signal light.●电动玩具、电动轮椅。

●Electric toy, electric wheel chair.3 电池结构Structure of the battery图1.蓄电池结构(12V系列) Fig.1 structrue of the storage battery (12V series)图2.蓄电池结构(2V系列) Fig.2 structrue of the storage battery (2V series)表1 SUPER FM GFM 系列蓄电池构件与功能Table.1 SUPER FM GFM series storage battery component and its function部件结构材料功能battery to be 13.5V. While float charge saturation state reaches, float charge current shall be generally 2-4mA for each AH, whose charging feature shown as Fig.5.浮充电压应根据温度变化进行调整，其校正系数K为-3mV/℃即Float charge voltage must be regulated in accordance with variation of temperature, herein ,calibrating coefficient K is -3mv/℃Vt=V25+K(t-25)具体选择可按图6进行。

1.“Materials science"involves investigating the relationships that exist between the structures and properties of materials. In contrast, "Materials engineering" involves, on the basis of these structur e-property correlations, designing or engineering the structure of a material to produce a predeter mined set of properties.“材料科学”涉及研究材料的结构和性能之间的关系。

相反，“材料工程”是指在这些结构和性能相关性的基础上，基于预期的性能来设计或生产有预定性能的材料。

2.Virtually all important Properties of solid materials may be grouped into six different categories: mechanical, electrical, thermal, magnetic, optical, and deteriorative实际上，固体材料的所有重要性质都可以分为六类：机械、电气、热、磁、光学和腐蚀性。

3.In addition to structure and properties, two other important components are involved in the scien ce and engineering of materials- namely“processing”and“performance”.除了结构和性能之外，材料科学和工程还涉及另外两个重要的组成部分，即“加工”和“性能”。

A 高分子化学和高分子物理UNIT 1 What are Polymer?第一单元什么是高聚物？What are polymers? For one thing, they are complex and giant molecules and are different from low molecular weight compounds like, say, common salt. To contrast the difference, the molecular weight of common salt is only 58.5, while that of a polymer can be as high as several hundred thousand, even more than thousand thousands. These big molecules or ‘macro-molecules’ are made up of much smaller molecules, can be of one or more chemical compounds. To illustrate, imagine that a set of rings has the same size and is made of the same material. When these things are interlinked, the chain formed can be considered as representing a polymer from molecules of the same compound. Alternatively, individual rings could be of different sizes and materials, and interlinked to represent a polymer from molecules of different compounds.什么是高聚物？首先，他们是合成物和大分子，而且不同于低分子化合物，譬如说普通的盐。

有关化学的英文摘要作文英文：Chemistry is a fascinating subject that explores the composition, structure, properties, and changes of matter. It plays a crucial role in our daily lives, from the food we eat to the medicines we take. As a chemistry enthusiast, I find the study of chemical reactions particularly intriguing. One of the most interesting aspects of chemistry for me is the concept of chemical bonding.Chemical bonding refers to the attractive forces that hold atoms together in compounds. There are three main types of chemical bonds: ionic, covalent, and metallic. Each type of bond has its own unique characteristics and properties. For example, ionic bonds form between a metal and a non-metal, resulting in the transfer of electrons from one atom to another. This creates positively and negatively charged ions that are attracted to each other, forming a strong bond. Covalent bonds, on the other hand,involve the sharing of electrons between two non-metal atoms, creating a stable molecule. Metallic bonds occur in metals, where the atoms share a sea of electrons, leading to excellent electrical conductivity and malleability.Understanding chemical bonding is essential for predicting the behavior of substances and designing new materials. For instance, the properties of materials like ceramics, polymers, and metals are determined by the type of chemical bonds present in their structure. By studying chemical bonding, scientists and engineers can develop new materials with specific properties, such as increased strength, flexibility, or conductivity.Furthermore, chemical bonding is crucial in the field of medicine. For example, the development of new drugs often involves understanding how molecules interact and bind to specific targets in the body. By studying the chemical bonding between drug molecules and their biological targets, researchers can design more effective and targeted medications with fewer side effects.In conclusion, the study of chemical bonding is essential for understanding the properties and behavior of matter. It has wide-ranging applications in fields such as materials science, medicine, and engineering. As a chemistry enthusiast, I am fascinated by the intricate ways in which atoms bond and interact with each other, shaping the world around us.中文：化学是一个迷人的学科，它探索物质的组成、结构、性质和变化。

大分子链间英文The interactions between polymer chains play a crucial role in determining the properties of a material. These interactions can be both intermolecular and intramolecular, and they can have a significant impact on the mechanical, thermal, and chemical properties of the polymer.Intermolecular interactions between polymer chains are primarily governed by van der Waals forces, hydrogen bonding, and electrostatic interactions. Van der Waals forces, which result from the fluctuating dipoles of polymer chains, are the most common type of intermolecular interaction in polymers. These forces are responsible for the cohesive energy of the polymer and play a key role in determining its physical properties, such as tensile strength and flexibility.In addition to van der Waals forces, hydrogen bonding can also occur between polymer chains that contain functional groups capable of forming hydrogen bonds. This type of interaction can significantly affect the mechanical properties of the polymer, as hydrogen bonding can lead to increased stiffness and strength.Electrostatic interactions, such as those between charged functional groups on polymer chains, can also contribute to the overall behavior of the material. These interactions can influence the polymer's thermal and electrical conductivity, as well as its resistance to chemical degradation.Intramolecular interactions within a polymer chain, on the other hand, are primarily determined by the chemical structure of the monomer units and the flexibility of the polymer chain. For example, the presence of aromatic rings or other rigid segments in the polymer chain can lead to increased stiffness and resistance to deformation, while flexible segments can impart greater elasticity and ductility.In summary, the interactions between polymer chains, both intermolecular and intramolecular, are critical in determining the overall properties of a polymer material. Understanding and controlling these interactions is essential for the development of new materials with tailored properties for specific applications.聚合物链之间的相互作用对于材料性能起着至关重要的作用。

液相包覆技术的方法英文回答：Liquid encapsulation techniques are valuable tools in various fields, including materials science, chemistry, and pharmaceuticals. These techniques involve encapsulating materials within liquid droplets or shells, offering unique advantages such as enhanced stability, controlled release, and improved functionality. Here are some commonly used liquid encapsulation techniques:Emulsion-based encapsulation: This method involves creating an emulsion, a mixture of two immiscible liquids, where one liquid is dispersed as droplets within the other. The droplets can then be encapsulated by coating them with a suitable material, forming microor nanocapsules.Coacervation: Coacervation is a process where oppositely charged polymers undergo electrostatic attraction, forming a complex that encapsulates the corematerial. The coacervate droplets can be further hardened or cross-linked to form stable capsules.Self-assembly: Self-assembly refers to the spontaneous organization of molecules into well-defined structures. In liquid encapsulation, self-assembling molecules can form micelles, vesicles, or other structures that encapsulate the target material.Layer-by-layer (LbL) assembly: LbL assembly is a technique where alternating layers of oppositely charged materials are deposited on the surface of a substrate or core material, creating a multilayer encapsulation system.Electrospinning: Electrospinning involves using an electric field to draw a charged liquid jet, whichsolidifies into fibers as it travels through the air. This technique can be used to encapsulate materials within the electrospun fibers.The choice of liquid encapsulation technique depends on factors such as the properties of the core material, thedesired release profile, and the intended application.中文回答：液相包覆技术在材料科学、化学和制药等领域具有重要价值。

中央民族大学《高分子专业英语》2023-2024学年第一学期期末试卷院(系)_______ 班级_______ 学号_______ 姓名_______1、There will be an endless power of youth supporting the Chinese nation’srejuvenation_______ the younger generation of the country has ideals , pursuits and shoulders.A．as far as B．so long asC．even if D．as if2、________some people criticize graffiti for being ugly and destructive, those graffiti lovers still see it as real art.A．As B．WhileC．Once D．Until3、The conference aims to develop business and let people think about _______ they can have a positive influence on the planet.A．why B．thatC．what D．how4、—What about your self-drive trip yesterday?—Tiring! The road was being widened, and we ________ a rough ride.A．had B．haveC．would have D．have had5、—I feel so nervous about the National English Speech Competition tomorrow.—.A．I really envy you B．Glad to hear thatC．Sounds great D．Take it easy6、The security judge was very _________ when she explained that the driving licence was necessary for her work .A．reasonable B．natural C．ridiculous D．available7、The general secretary stressed that what he had just said was only his _________view, not official intentions.A．private B．separate C．personal D．single8、-- - Are you satisfied with this house?----________. We can’t have a nicer oneA．Not a little B．Not a bit C．A little D．A bit9、---I did really well in the examination, Li Ke.---I did _________. I got full mark.A．no less B．not less C．not worse D．no worse10、A good suitcase is essential for someone who is ______ as much as Jackie is.A．on the rise B．on the lineC．on the spot D．on the run第二部分阅读理解（满分20分）阅读下列短文，从每题所给的A、B、C、D四个选项中，选出最佳选项。