Chapter 15-Polymer Properties
碳陶复合材料英文专著
碳陶复合材料英文专著Carbon-Ceramic Composite MaterialsIntroduction:Carbon-ceramic composite materials are a class of advanced materials that exhibit exceptional mechanical properties, high thermal stability, and excellent electrical conductivity. These materials are widely used in various industries, including aerospace, automotive, electronics, and healthcare, due to their unique combination of properties. This book aims to provide a comprehensive overview of carbon-ceramic composite materials, including their synthesis, characterization, properties, and applications.Chapter 1: Introduction to Carbon-Ceramic Composite Materials - Historical background and development of carbon-ceramic composites- Importance and advantages of carbon-ceramic composites- Different types of carbon-ceramic compositesChapter 2: Synthesis Methods- Fabrication techniques for carbon-ceramic composites- Chemical vapor deposition (CVD) process- Polymer-derived ceramics (PDCs) route- Pyrolysis and carbonization methods- Additive manufacturing techniques for carbon-ceramic compositesChapter 3: Characterization Techniques- Microstructural analysis using scanning electron microscopy(SEM) and transmission electron microscopy (TEM)- X-ray diffraction (XRD) and Raman spectroscopy for phase identification and crystal structure analysis- Thermal analysis techniques, such as thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC)- Mechanical testing methods, including tensile, compressive, and flexural strength testsChapter 4: Properties of Carbon-Ceramic Composites- Mechanical properties, such as hardness, toughness, and elastic modulus- Thermal properties, including thermal conductivity and coefficient of thermal expansion- Electrical conductivity and electromagnetic properties- Chemical resistance and corrosion behavior- Wear and friction propertiesChapter 5: Applications of Carbon-Ceramic Composites- Aerospace applications, such as aircraft brakes and thermal protection systems- Automotive applications, including brake discs and clutch plates - Electronics and semiconductor industry applications- Biomedical applications, like orthopedic implants and dental prosthetics- Energy storage and conversion applications, such as fuel cells and batteriesChapter 6: Future Perspectives and Challenges- Emerging trends and future developments in carbon-ceramic composites- Challenges and limitations in the synthesis and processing of these materials- Environmental and sustainability considerations- Potential applications in emerging fields, such as renewable energy and 3D printingConclusion:Carbon-ceramic composites are a fascinating class of materials that possess a wide range of exceptional properties. This book provides a comprehensive overview of the synthesis, characterization, properties, and applications of carbon-ceramic composites, aiming to serve as a valuable reference for researchers, engineers, and students in the field. With increasing interest and advancements in this area, carbon-ceramic composites are expected to find even more extensive applications in the future, contributing to technological advancements in various industries.。
fireretardancyofpolymericmaterials：高分子材料的阻燃性
Second EditionFire Retardancy of Polymeric MaterialsEdited byCharles A.Wilkie•Alexander B.MorganCRC PressTaylor&Francis GroupBoca Raton London New YorkCRC Press is an imprint of theTaylor&Francis Croup,an informs businessContentsPreface ix Contributors xiChapter1An Introduction to Polymeric Flame Retardancy,Its Rolein Materials Science,and the Current State of the Field1Alexander B.Morgan and Charles A.WilkieChapter2Polymer Degradation and the Matching of FR Chemistry to Degradation15 Dennis Price and A.Richard HorrocksChapter3Physical Parameters Affecting Fire Growth43 Jose L.Torero and Guillermo ReinChapter4Halogen-Containing Flame Retardants75 Sergio Bocchini and Giovanni CaminoChapter5Phosphorus-Based Flame Retardants107 Paul Joseph and John R.EbdonChapter6Intumescence-Based Fire Retardants129 Serge Bourbigot and Sophie DuquesneChapter7Fire-Retardant Fillers163 Peter HornsbyChapter8Recent Developments in Silicon-Based Flame Retardants187 Walid H.AwadChapter9Boron-Based Flame Retardants and Flame Retardancy207 Kelvin K.Shen,Saied H.Kochesfahani,and Frederic JouffretChapter10Char Formation and Characterization239 Sophie Duquesne and Serge BourbigotChapter11Polymer Nanocomposites261 David D.JiangContents Chapter12Multicomponent FR Systems:Polymer NanocompositesCombined with Additional Materials301J.-M.Lopez.-Cuesta and outidChapter13Design ol"Interlayers for Fire-Retarded Polymeric Systems329 Gyorgy Marosi,Botond B.Marosfoi,Brigitta Bodzay,Tamds Igricz,and Gytirgy BertalanChapter14Fundamentals of Fire Testing and What Tests Measure349 Marc JanssensChapter15Uses of Fire Tests in Materials Flammability Development387 Bernhard SchartelChapter16High Throughput Techniques for Fire Resistant Materials Development421 Rick D.Davis,Richard E.Lyon,Michael T.Takemori,and Naomi EidelmanChapter17Fire Toxicity and Its Assessment453 Anna A,Stec and T,Richard HullChapter18Modeling Thermal Degradation of Polymers by PopulationBalance Methods479J.E.J.StaggsChapter19Micro-to Mesoscale Testing and Modeling for NanocompositePolymers in Fires509Michael A.Delichatsios and Jianping ZhangChapter20Full-Scale Fire Modeling551 Chris Lautenberger and Simo HostikkaChapter21Regulations,Codes,and Standards Relevant to Fire Issuesin the United States587Marcelo M.HirschlerChapter22Changing Chemical Regulations and Demands671 Susan ndryChapter23Flame Retardant Design for Fiber-Reinforced Materials703 Michael G.Stevens and Alexander B.MorganContentsChapter24Flame Retardancy Design for Textiles725 Baljinder K.KandolaChapter25FR Design for Foam Materials763 Michele Modesti and Alessandra LorenzettiChapter26Material Design for Fire Safety in Wire and Cable Applications783 Jeffrey M.Cogen,Thomas S.Lin,and Paul D.WhaleyIndex809Below is given annual work summary, do not need friends can download after editor deleted Welcome to visit againXXXX annual work summaryDear every leader, colleagues:Look back end of XXXX, XXXX years of work, have the joy of success in your work, have a collaboration with colleagues, working hard, also have disappointed when encountered difficulties and setbacks. Imperceptible in tense and orderly to be over a year, a year, under the loving care and guidance of the leadership of the company, under the support and help of colleagues, through their own efforts, various aspects have made certain progress, better to complete the job. For better work, sum up experience and lessons, will now work a brief summary.To continuously strengthen learning, improve their comprehensive quality. With good comprehensive quality is the precondition of completes the labor of duty and conditions. A year always put learning in the important position, trying to improve their comprehensive quality. Continuous learning professional skills, learn from surrounding colleagues with rich work experience, equip themselves with knowledge, the expanded aspect of knowledge, efforts to improve their comprehensive quality.The second Do best, strictly perform their responsibilities. Set up the company, to maximize the customer to the satisfaction of the company's products, do a good job in technical services and product promotion to the company. And collected on the properties of the products of the company, in order to make improvement in time, make the products better meet the using demand of the scene.Three to learn to be good at communication, coordinating assistance. On‐site technical service personnel should not only have strong professional technology, should also have good communication ability, a lot of a product due to improper operation to appear problem, but often not customers reflect the quality of no, so this time we need to find out the crux, and customer communication, standardized operation, to avoid customer's mistrust of the products and even the damage of the company's image. Some experiences in the past work, mentality is very important in the work, work to have passion, keep the smile of sunshine, can close the distance between people, easy to communicate with the customer. Do better in the daily work to communicate with customers and achieve customer satisfaction, excellent technical service every time, on behalf of the customer on our products much a understanding and trust.Fourth, we need to continue to learn professional knowledge, do practical grasp skilled operation. Over the past year, through continuous learning and fumble, studied the gas generation, collection and methods, gradually familiar with and master the company introduced the working principle, operation method of gas machine. With the help of the department leaders and colleagues, familiar with and master the launch of the division principle, debugging method of the control system, and to wuhan Chen Guchong garbage power plant of gas machine control system transformation, learn to debug, accumulated some experience. All in all, over the past year, did some work, have also made some achievements, but the results can only represent the past, there are some problems to work, can't meet the higher requirements. In the future work, I must develop the oneself advantage, lack of correct, foster strengths and circumvent weaknesses, for greater achievements. Looking forward to XXXX years of work, I'll be more efforts, constant progress in their jobs, make greater achievements. Every year I have progress, the growth of believe will get greater returns, I will my biggest contribution to the development of the company, believe inyourself do better next year!I wish you all work study progress in the year to come.。
Chapter15 Carbohydrates
Mutarotation
+112.0
+18.7
+52.7 at an equilibrium
Interconversion of ketose and aldose
Monosaccharide Derivatives
Reducing sugars: sugars with free anomeric carbons - they will reduce oxidizing agents, such as peroxide, ferricyanide and some metals (Cu and Ag) These redox reactions convert the sugar to a sugar acid
Arabinose is an epimer of ribose Xylose is an epimer of ribose Fructose is the ketose form of glucose
Cyclic monsaccharide structures & anomeric forms
Some naturally-occurring disaccharides
The Glycosidic Bond
Two sugar molecules can be joined in tandem, when a hydroxyl (alcohol) group of one sugar displaces the hydroxyl group on the other sugar’s anomeric carbon. The bond formed is called a glycosidic bond. In forming the glycosidic bond, an acetal is generated on one sugar (at carbon 1) in place of the hemiacetal. Convince yourself that the other carbon (carbon 4) is not an acetal. Similarly to peptide bond formation, one mole of water is formed per glycosidic bond generated. The disaccharide formed upon condensation of two glucose molecules is called Maltose.
高分子材料工程专业英语课文翻译 (2)
高分子材料工程专业英语课文翻译Polymer Science and Polymer Engineering are closely related andoften used interchangeably. Polymer Science is concerned with the chemistry and physics of polymers, while Polymer Engineering teaches students how to design and manufacture polymer products. No matter which field you choose, there is constant innovation and new developments in the field of Polymer Science and Engineering.高分子科学和高分子工程密切相关，常常互换使用。
高分子科学研究聚合物的化学和物理学，而高分子工程则教授学生如何设计和制造聚合物产品。
无论您选择哪个领域，高分子科学和工程的领域中都不断有创新和新发展。
Polymers are large molecules that are made up of repeating units called monomers. These molecules are characterized by their high molecular weight, which gives them unique properties such as strength, elasticity, and durability. There are many types of polymers, including plastics, rubbers, and fibers.聚合物是由称为单体的重复单位组成的大分子。
性质用英语怎么说
性质用英语怎么说性能作为中药学术语应用时，泛指药物的四气、五味、归经、升降沉浮、补泻等特性和功能。
产品性能是指产品具有适合用户要求的物理、化学或技术性能，如强度、化学成份、纯度、功率、转速等。
那么你知道性质用英语怎么说吗?下面来学习一下吧。
性质的英语说法1：nature性质的英语说法2：property性质的相关短语：化学性质chemical property ; propriété chimique ; chemical properties ; chemistry一致性质 Uniform property ; uniform property城市性质 designated function of city ; city properties ; city's quality ; city s properties光学性质 Optical Properties ; Optical property ; Photornetrics ; Optical机械性质Mechanical Properties ; mechanical property ; engineering properties ; Mechanical property广度性质 extensive property ; extensive properties ; extensive quantity ; extensive proper-ties工作性质 job specification ; Nature of Work ; Job nature ; job category企业性质Person ; typeid ; Enterprise Nature ; Business Properties资本性质 capital nature性质的英语例句：1. The nature of the polymer is currently a trade secret.这一聚合物的性质目前是个商业机密。
聚合物电学性能
Chapter10 聚合物的电性能
• 热合PVC等极性材料是适宜的。而PE薄膜等非极 性材料就很难用高频热合。
• 轮胎经高频热处理消除内应力，可大幅度延长使 用寿命。
• 塑料注射成型时常因含水而产生气泡，经高频干 燥能很好解决这个问题。
Chapter10 聚合物的电性能
(3)高聚物的介电松弛谱
□ 高分子分子运动的时间与温度依赖性可在其介电性质上得 到反映。借助于介电参数的变化可研究聚合物的松弛行为。
以上两种极化统称为变形极化或诱导极化 其极化率不随温度变化而变化，聚合物在高频区均能发生变 形极化或诱导极化
Chapter10 聚合物的电性能
• 偶极极化（取向极化）：
是具有永久偶极矩的极性分子沿外场方向排列的现象。极 化所需要的时间长，一般为10-9s，发生于低频区域。
(a)无电场
（b）有电场
图1 偶极子在电场中取向
Chapter10 聚合物的电性能
三、影响聚合物介电性能的因素
• 高分子材料的介电性能首先与材料的极性有关。 这是因为在几种介质极化形式中，偶极子的取向 极化偶极矩最大，影响最显著。
• 决定聚合物介电损耗大小的内在因素： ①分子极性大小和极性基团的密度 ② 极性基团的可动性
Chapter10 聚合物的电性能
Chapter10 聚合物的电性能
• 介电损耗温度谱示意图
在这些图谱上，高聚物的介电损耗一 般都出现一个以上的极大值，分别对 应于不同尺寸运动单元的偶极子在电 场中的介电损耗(因偶极子的取向极化 过程伴随着分子运动过程，运动模式 各异，其松弛时间也不一致,其受阻程 度不同)按照这些损耗峰在图谱上出现 的先后，在温度谱上从高温到低温， 在频率谱上从低频到高频，依次用、 、命名。
化学化工专业英语电子版课本
化学化工专业英语电子版课本————————————————————————————————作者：————————————————————————————————日期：ContentPART 1 Introduction to Materials Science ＆Engineering 1 Unit 1 Materials Science and Engineering 1 Unit 2 Classification of Materials 9 Unit 3 Properties of Materials 17 Unit 4 Materials Science and Engineering: What does the Future Hold? 25 Part ⅡMETALLIC MATERLALS AND ALLOYS 33 Unit 5 An Introduction to Metallic Materials 33 Unit 6 Metal Manufacturing Methods 47 Unit 7 Structure of Metallic Materials 57 Unit 8 Metal-Matrix Composites 68 PartⅢCeramics 81 Unit 9 Introduction to Ceramics 81 Unit 10 Ceramic Structures —Crystalline and Noncrystalline 88 Unit 11 Ceramic Processing Methods 97 Unit 12 Advanced ceramic materials –Functional Ceramics 105 PARTⅣNANOMATERIALS 112 Unit 13 Introduction to Nanostructured Materials 112 Unit14 Preparation of Nanomaterials 117 Unit 15 Recent Scientific Advances 126 Unit 16 The Future of Nanostructure Science and Technology 130 Part ⅤPOLYMERS 136Unit17 A Brief Review in the Development of Synthetic Polymers 136 Unit18 Polymer synthesis: Polyethylene synthesis 146 Unit19 Polymer synthesis:Nylon synthesis 154 Unit 20 Processing and Properties Polymer Materials 165 PART VI POLYMERIC COMPOSITES 172 Unit21 Introduction to Polymeric Composite Materials 172Unit22 Composition, Structure and Morphology of Polymeric Composites 178 Unit23 Manufacture of Polymer Composites 185 Unit24 Epoxy Resin Composites 191 Part 7 Biomaterial 196 Unit 25 Introduction to Biomaterials 196 Unit 26 Biocompatibility 205 Unit 27 Polymers as Biomaterials 213 Unit 28 Future of Biomaterials 224 PARTⅧMaterials and Environment 237 Unit29 Environmental Pollution & Control Related Materials 237 Unit30 Bio-degradable Polymer Materials 241 Unit 31 Environmental Friendly Inorganic Materials 248 Unit 32 A Perspective on the Future: Challenges and Opportunities 256 附录一科技英语构词法263 附录二科技英语语法及翻译简介269 附录三：聚合物英缩写、全名、中文名对照表280 附录四：练习题参考答案284PART 1 Introduction to Materials Science ＆EngineeringUnit 1Materials Science and Engineering Historical PerspectiveMaterials are probably more deep-seated in our culture than most of us realize. Transportation, housing, clothing, communication, recreation, and food production —virtually every segment of our everyday lives is influenced to one degree or another by materials. Historically, the development and advancement of societies have been intimately tied to the members’ ability to produce and manipulate materi- als to fill their needs. In fact, early civilizations have been designated by the level of their materials development (Stone Age, Bronze Age, Iron Age).The earliest humans had access to only a very limited number of materials, those that occur naturally: stone, wood, clay, skins, and so on. With time they discovered techniques for producing materials that had properties superior to those of the natural ones; these new materials included pottery and various metals. Furthermore, it was discovered that the properties of a material could be altered by heat treatments and by the addition of other substances. At this point, materials utilization was totally a selection process that involved deciding from a given, rather limited set of materials the one best suited for an application by virtue of its characteristics.①It was not until relatively recent times that scientists came to understand the relationships between the structural elements of materials and their properties. This knowledge, acquired over approximately the past 100 years, has empowered them to fashion, to a large degree, the characteristics of materials. Thus, tens of thousands of different materials have evolved with rather specialized charac- teristics that meet the needs of our modern and complex society; these include metals, plastics, glasses, and fibers. deep-seated根深蒂固的, 深层的pottery / ☐♦☯❒♓/ ⏹ 陶器structural elements结构成分；property / ☐❒☐☜♦♓/⏹.性能The development of many technologies that make our existence so comfortable has been intimately associated with the accessibility of suitable materials. An advancement in the understanding of a material type is often the forerunner to the stepwise progression of a technology. For example, automobiles would not havebeen possibl- e without the availability of inexpensive steel or some other comparable substitute. In our contemporary era, sophisticated electronic devices rely on components that are made from what are called semiconducting materials. Materials Science and EngineeringThe discipline of materials science involves investigating the relationships that exist between the structures and properties of materials. In contrast, materials engineering is, on the basis of these structure–property correlations, designing or engineering the structure of a material to produce a predetermined set of properties.“Structure’’ is at this point a nebulous term that deserves some explanation. In brief, the structure of a material usually relates to the arrangement of its internal components. Subatomic structure involves electrons within the individual atoms and interactions with their nuclei. On an atomic level, structure encompasses the organization of atoms or molecules relative to one another. The next larger structural realm, which contains large groups of atoms that are normally agglomerated together, is termed ‘‘microscopic,’’ meaning that which is subject to direct observation using some type of microscope. Finally, structural elements that may be vie wed with the naked eye are termed ‘‘macroscopic.’’The notion of ‘‘property’’ deserves elaboration. While in service use, all materials are exposed to external stimuli that evoke some type of response. For example, a specimen subjected to forces will experience deformation; or a polished metal surface will reflect light. Property is a material trait in terms of the kind and magnitude of response to a specific imposed stimulus. Generally, definitions of properties are made independent of material shape and size.Virtually all important properties of solid materials may be grouped into six different categories: mechanical, electrical, thermal, magnetic, optical, and stepwise / ♦♦♏☐♦♋♓/ ♎逐步的sophisticated/♦☯♐♓♦♦♓ ♏♓♦♓♎/ ♎精制的，复杂的；semiconducting materials 半导体材料nebulous/ ⏹♏♌✞●☯♦/♎ 含糊的，有歧义的subatomic/ ♦✈♌☯♦❍/♎ 亚原子的microscopic/❍♓❒☯♦☐♓/ ♎微观的❍♋♍❒☐♦♍☐☐♓♍/❍✌ ❒☯✞♦☐♓/♎宏观的deteriorative. For each there is a characteristic type of stimulus capable of provokingdifferent responses. Mechanical properties relate deformation to an applied load or force; examples include elastic modulus and strength. For electrical properties, such as electrical conductivity and dielectric constant, the stimulus is an electric field. The thermal behavior of solids can be represented in terms of heat capacity and thermal conductivity. Magnetic properties demonstrate the response of a material to the application of a magnetic field. For optical properties, the stimulus is electro- magnetic or light radiation; index of refraction and reflectivity are representative optical properties. Finally, deteriorative characteristics indicate the chemical reactivity of materials.In addition to structure and properties, two other important components are involved in the science and engineering of materials, viz. ‘‘processing’’ and ‘‘performance.’’ With regard to the relationships of these four components, the structure of a material will depend on how it is processed. Furthermore, a material’s performance will be a function of its properties.Fig. 1.1 Photograph showing the light transmittance of three aluminum oxide specimens. From left to right: single crystal material (sapphire), which is transparent;a polycrystalline and fully dense (nonporous) material, which is translucent; and a polycrystalline material that contains approximately 5% porosity, which is opaque. (Specimen preparation, P. A. Lessing; photography by J. Telford.)We now present an example of these processing-structure-properties-perfor- mance principles with Figure 1.1, a photograph showing three thin disk specimens placed over some printed matter. It is obvious that the optical properties (i.e., the deformation/ ♎♓♐ ❍♏♓☞☯⏹/ ⏹变形deteriorative/♎♓♦♓☯❒♓☯❒♏♓♦♓❖/ ⏹破坏（老化的）elastic modulus 弹性模量strength /♦♦❒♏⏹♑/ ⏹强度；dielectric constant介电常数；heat capacity 热容量refraction/❒♓♐❒✌☞☯⏹/ ⏹折射率；reflectivity/ ❒♓♐●♏ ♦♓❖♓♦♓/ ⏹反射率processing/☐❒☯◆♦♏♦♓☠/ ⏹加工light transmittance) of each of the three materials are different; the one on the left is transparent (i.e., virtually all of the reflected light passes through it), whereas the disks in the center and on the right are, respectively, translucent and opaque.All of these specimens are of the same material, aluminum oxide, but the leftmost one is what we call a single crystal—that is, it is highly perfect—which gives rise to its transparency. The center one is composed of numerous and verysmall single crystals that are all connected; the boundaries between these small crystals scatter a portion of the light reflected from the printed page, which makes this material optically translucent.②And finally, the specimen on the right is composed not only of many small, interconnected crystals, but also of a large number of very small pores or void spaces. These pores also effectively scatter the reflected light and render this material opaque.Thus, the structures of these three specimens are different in terms of crystal boundaries and pores, which affect the optical transmittance properties. Furthermore, each material was produced using a different processing technique. And, of course, if optical transmittance is an important parameter relative to the ultimate in-service application, the performance of each material will be different.Why Study Materials science and Engineering?Why do we study materials? Many an applied scientist or engineer, whether mechanical, civil, chemical, or electrical, will at one time or another be exposed to a design problem involving materials. Examples might include a transmission gear, the superstructure for a building, an oil refinery component, or an integrated circuit chip. Of course, materials scientists and engineers are specialists who are totally involved in the investigation and design of materials.Many times, a materials problem is one of selecting the right material from the many thousands that are available. There are several criteria on which the final decision is normally based. First of all, the in-service conditions must be charac- terized, for these will dictate the properties required of the material. On only rare occasions does a material possess the maximum or ideal combination of properties. transmittance/♦❒✌⏹❍♓♦☜⏹♦/ ⏹. 透射性sapphire /♦✌♐♓☯/ ⏹蓝宝石transparent/♦❒✌⏹♦☐☪☯❒☯⏹♦/ ♎透明的；polycrystalline/ ☐●♓❒♓♦♦☯●♓⏹/ ⏹多晶体；translucent/♦❒✌⏹●✞♦⏹♦/♎ 半透明的；opaque☯✞☐♏♓♎不透明的single crystal 单晶体Thus, it may be necessary to trade off one characteristic for another. The classic example involves strength and ductility; normally, a material having a high strength will have only a limited ductility. In such cases a reasonable compromise between two or more properties may be necessary.A second selection consideration is any deterioration of material properties that may occur during service operation. For example, significant reductions in mecha- nical strength may result from exposure to elevated temperatures or corrosive envir- onments.Finally, probably the overriding consideration is that of economics: What will the finished product cost? A material may be found that has the ideal set of proper- ties but is prohibitively expensive. Here again, some compromise is inevitable.The cost of a finished piece also includes any expense incurred during fabrication to produce the desired shape. The more familiar an engineer or scientist is with the various characteristics and structure–property relationships, as well as processing techniques of materials, the more proficient and confident he or she will be to make judicious materials choices based on these criteria.③Reference:William D. Callister,Materials science and engineering :anintroduction, Press:JohnWiley & Sons, Inc.,2007;2-5 transmission gear传动齿轮dictate/♎♓♦♏♓♦/ ❖ 决定trade off 权衡；折衷ductility♎✈♦♓●♓♦♓⏹延展性overriding/ ☯✞❖☯❒♋♓♎♓☠/♎最主要的judicious/♎✞✞♎♓☞☯♦/♎明智的Notes1．At this point, materials utilization was totally a selection process that involved deciding froma given, rather limited set of materials the one best suited for an application by virtue of itscharacteristics由此看来，材料的使用完全就是一个选择过程，且此过程又是根据材料的性质从许多的而不是非有限的材料中选择一种最适于某种用途的材料。
POLYMERS 聚合物
01.POLYMERSIntroductionThe term macromolecule, or polymer, is applied to substances of high molecular weight that are composed of a large number (usually at least 100) of units of low molecular weight joined by covalent bonds. If the low molecular weight units making up the macromolecule are bonded end-to-end in a long chain and no covalent chemical bonds exist between the chains, the macromolecules are called linear polymers. Such polymers, unless of extremely high molecular weight (1000000) ,can usually be dissolved and, when heated, they soften or melt so that they can be extruded into fibers or molded into desired shapes. These polymers are said to be thermoplastic. On the other hand, if the polymer chains are linked together at numerous points, the polymer is one large three-dimensional molecule, infusible and insoluble. Such polymers are called cross-linked polymers, and the bonds connecting the chains are cross-links. Certain linear polymers, referred to as thermosetting, contain groups which, when heated, react to give cross-linked polymers.The process by which small molecules undergo multiple combinations to form macromolecules is polymerization. Small molecules from which a macromolecule or polymer can be made are called monomers. Two types of polymerization are recognized: ( 1 ) condensation polymerization and ( 2 ) addition polymerization. A polymer-forming reaction involving elimination of a small molecule such as water or alcohol between monomer units is described as condensation polymerization. In addition polymerization, unsaturated or cyclic molecules add to each other without elimination of any portion of the monomer molecule. The empirical formula of the polymer is then, of course, the same as that of the monomer.Reactions capable of forming macromolecules by either addition or condensation polymerization must be functionally capable of proceeding indefinitely. Whenever two monomer molecules react, the product must contain a functional group capable ofreacting with another molecule of monomer. In condensation polymerization, each monomer unit must have at least two functional groups. In addition polymerization, the monomer need have only one functional group------the presence of two or more functional groups usually leads to the production of cross-linked addition polymers. Examples of some of the more important synthetic polymers formed by condensation polymerization are listed in Table 15.1. Condensation PolymersTypical of condensation polymers are the polyamides or "nylons" formed by the condensation reaction of a diacid with a diamine. Nylon 66, poly (hexamethyleneadipa-mide), is formed by heating an equimolar mixture of adipic acid and liexamethylenediamine at a temperature of 215° for several hours and then at 270°under vacuum for about one hour.In the laboratory, nylons are more conveniently prepared by a polymer-forming reaction called interfacial polymerization. The reaction is between a diacid chloride dissolved in a water-immiscible organic solvent and a water solution of a diamine. Reaction apparently occurs at the interface of two solutions.Experimental (Preparation of Nylon 6—10)Place a solution of 2.0 ml. of sebacoyl chloride in 100 ml. of carbon tetrachloride in a 200-ml. tall-form beaker. Over the acid chloride solution carefully pour a solution of 2.2 g. of liexamethylenediamine and 1.5 g. of sodium hydroxide in 50 ml. of water. The addition of the diamine-sodium hydroxide solution is best done by pouring the solution through a funnel placed so that its outlet is just over the surface of the diacid solution. Grasp the polymeric film which forms at the interface of the two solutions with forceps and raise it from the beaker as continuously forming rope. If a mechanical windup device is placed above the beaker, the polymer may be wound up continuously until one of the reactants is exhausted.Wash the polymer thoroughly with water and finally with a 50% acetone solution. Allow the washed polymer to air dry. Place about 0.l g. of the dried polymer on ametal spatula or spoon and melt it carefully over a low flame care being taken not to char the polymer1. Touch a glass rod or a matchstick to the molten polymer and pull it slowly away to form a fiber.2. Addition PolymersIntroductionAddition polymerization usually must be catalyzed by a base, by an acid, or by free radicals. Three stages are involved in all addition polymerization reactions, no matter what the catalyst: these are initiation, propagation, and termination. In the initiation step, the catalyst molecules attack the monomers to give intermediates which, during the propagation stage. are capable of attacking other molecules of monomer with lengthening of the chain. In the termination step, chain growth is stopped by elimination of a group from the reacting end of the chain or by addition of a group to the end of the chain to form a molecule which is no longer a chain carrier.Free radical-initiated polymerizations follow a similar course but with radical. rather than ionic, intermediates. If two or more monomers undergo addition polymerization together, the process is called copoiymerization . and the product is a copolymer. Should one of the monomers (even though present in only minor amounts) from which a copolymer is formed contain two or more groups capable of undergoing addition polymerization, the copolymer will be insoluble as a result of cross-linking2.Examples of some of the more important synthetic polymers formed by addition polymerization are listed in Table 16.Preparation of Polystyrene(1 )Polymerization of Styrene with Benzoyl Peroxide. To a large test tube add 20 ml. of toluene and 5 ml. of styrene. Then add 0.3g. of benzoyl peroxide and place the test tube in a beaker of water which is maintained at a temperature of 90°—95°. After 60 minutes, re move the test tube, allow the contents to cool for 5 minutes, and note the viscosity of the solution. Pour the solution into 200ml. of methyl alcoholcontained in a 400-ml. beaker. Collect the white precipitate of polystyrene by filtration, using a Buchner funnel, and wash the precipitate on the funnel with 50 ml. of methyl alcohol. Remove the precipitate from the funnel and spread it out to dry on a large, clean sheet of filter paper.Place 3 ml. of acetone in a clean test tube, add 0.2g. of the dried polymer, and stir the mixture for several minutes. Is the polymer soluble? Use this same procedure to determine the solubility of polystyrene in water, ethyl alcohol, benzene, carbon tetrachloride, and petroleum ether. Place approximately 0.l g. of the polymer on a metal spatula or spoon and warm it gently over a flame until the polymer melts. To the molten polymer touch a glass stirring rod or a matchstick and pull away gently todraw out a fiber. How would you describe the properties of the fiber as to brittleness, color, and strength? Compare the properties of this polystyrene fiber with those of the Nylon fiber. Allow the molten polymer on the spatula to cool. Describe the appearance of the cooled polymer. Scrape this material from the spatula, place it in a test tube, and determine its solubility in acetone. Did melting change the solubility of the polystyrene?。
专业英语第二章翻译
Chapter 2 Boiler第二章锅炉Air heater 空预器Commissioning 试运行Anchor 支座，固定Compressor 压缩机、压气机Anhydrous ammonia 无水氨Condenser 凝汽器Anthracite 无烟煤Containment 反应堆安全壳Atomized 雾化Convection 对流Austenitic 奥氏体钢Coolant 制冷剂Auxialiary 辅助机械Coordinated 坐标，定位Axis 轴Corten低合金耐腐蚀钢Bagasse 甘蔗渣Counterflow 逆流（换热器）Bare tube 光管Creep strength 蠕变强度Bark 树皮Criterion 标准Beam 梁，横梁Critical pressure 临界压力Bituminous coal 烟煤Culm 煤屑Blade 叶片Cyclone furnace 旋风炉Blast 鼓风Debris 残骸、有机残留物Blowdown 排污Decane 癸烷Boiler 锅炉Decay 分解Bulk 大块的Deposited 沉积，沉淀的Burner zone 燃烧器区域Deterioration 恶化Butane 丁烷Diesel oil 柴油Calcination 煅烧Differential 差动，微分Capacity 出力Distillate 馏出物Carbon steel 碳钢Distortion 变形Cerium 铈Division wall 分隔墙，双面水冷壁Chromium 铬Drainage 疏水Circulating fluidized bed CFB 循环流化Drum 汽包床锅炉Coal char 煤焦Dwell time 保留时间Cogenerator 热电联产机组Economizer 省煤器Combustion 燃烧Embrittlement 脆性，脆化Equalization 均衡，平衡Ingress进口，入口Erosive 侵蚀的，腐蚀的In-line 顺列Ethane 乙烷Inorganic 无机的Evaluate 评估，评价Ion 离子Evaporate 蒸发Jurisdiction 权限Excess air 过量空气Lignite 褐煤Extended surface 扩展受热面Lime 石灰Fatigue 疲劳Limestone 石灰石Feedwater 给谁Low alloy 低合金钢Ferrite 铁素体Low-volatile 低挥发分的Fin 鳍片，肋片Margin 裕量，安全系数Flange 法兰Matrix 矩阵Flue gas 烟气Membrane 膜Fouling 沾污Methane 甲烷Furnace 炉膛Mill 磨煤机Generator 发电机Molecule 分子Geological 地质的Molten 熔化Girth 环形Nitric oxide 氮氧化物Govern 控制、调节Nonpressure 非承压的Gravity 重力Nontoxic 无毒的Header 联箱，集箱Organisms 有机体Helical 螺旋状的Oxidation 氧化Helium 氦Peat 泥煤Heterogeneous 不均匀的Pendants superheat platen悬吊式屏式过热器Hopper 斗，料斗Pentane 戊烷Husk 壳，外壳Petrochemical 石油化工制品Hydraulic 水力的，液压的Petroleum 石油制品Ignite 点火Plasma spray coating 等离子喷涂Impurity 杂质Platen 屏Inert 惰性Polymer 聚合物Inferior 低级的，劣质的Pores 气孔，小孔Ingredients 成分Porosity多空的Potassium 钾Slurry 水煤浆Prandtl numbers 普朗特数Sodium 钠Prefabricated 预制的Solvents 溶剂Premium fuel 优质燃料Sootblower 吹灰器Pressure loss 压力损失Sour gas 含硫气体Primary air 一次风Specification 规格Propane 丙烷Stable ignition 稳定着火Proximate analysis 工业分析Stanton number 斯坦顿数Pulp 纸浆Saturated 饱和的Pyrites 黄铁矿Straw 稻草Radius 半径，范围Steam line blowing 蒸汽管路吹灰Rare earth element 稀土元素Steams 茎，杆Recuperator 间壁式换热器Stress corrosion 应力腐蚀Regenerator 回热器，蓄热器Structural formula 结构式Regulate 控制，调节Stud 双头螺栓Repercussions 反应Subbituminous 贫煤，次烟煤Reservoirs 储气罐Suction 真空，负压Residuale fuel oil 渣油Sulphur 硫Resonant 共振Superheater 过热器Retract缩回Swamp 沼泽Reynolds number 雷诺数Sweet gas 无硫气Rigid 刚性的，紧密地Switchgear 配电装置，开关装置Rollers 辊子Temperature-entropy 温熵图Scale 水垢，Tenacious 黏的Seal 密封Thermodynamics 热力学Sedimentary 沉积Tube bundles 管束Serpentine tube 蛇形管Tubular 管状的Shale 页岩Turbine 汽轮机Silica 二氧化硅V elocity 速度Silt 淤泥V ertical spidle mill 中速磨，立轴磨Single-phase 单相V essel 容器Skin casing 外护板Viscosity 黏度Slag 结渣V olumetric expansion 体膨胀Vulnerable 易损的，薄弱的DEH 数字电液系统Wear磨损DNB 偏离核态沸腾Welded 焊接FDF 送风机Wingwall屏式凝渣管FGD 烟气脱硫Yttrim 釔FSSS 炉膛安全检测保护系统Abbreviations HRB 回热锅炉AFBC 常压流化床燃烧IDF 引风机AFCO 燃料自动切断IGCC 整体煤气化联合循环AFWC 给水自动切断LMTD 对数平均温差ASME 美国机械工程师协会MFT 主燃料切断ATM 标准大气压MUF 锅炉补给水BFP 锅炉给水泵NWL 正常水位BUT 按钮OFA 火上风，燃尽风BWC锅炉水浓度PFBC 增压流化床燃烧BYP 旁路SSC 刮板除渣机CFBB 循环流化床锅炉TGA 热重分析仪MCR 最大连续蒸发量UBC 未燃烧DAS 数据采集系统WFGD 湿法烟气脱硫2.1 IntroductionBoilers use heat to convert water into steam for a variety of applications. Primary among these are electric power generation and industrial process heating. Steam has become a key resource because of its wide availability, advantageous properties and non toxic nature. The steam flow rates and operating conditions can vary dramatically; from 1000lb/h (0.1kg/s) in one process use to more than 10 million lb/h (1260kg/s) in large electric power plant; from about 14.7 psi (1 bar) and 212ºF in some heating applications to more than 4500 psi (310bar) and 1100ºF (593℃) in advanced cycle power plant.2.1 简介SSC锅炉利用热量使水转变成蒸汽以进行各种利用。
小学下册第十四次英语第6单元真题[含答案]
小学下册英语第6单元真题[含答案]考试时间：90分钟（总分:110）A卷一、综合题(共计100题共100分)1. 填空题：I love to play ______ (户外运动) with my friends. It keeps us active and healthy.2. 听力填空题：Learning new languages fascinates me. It opens doors to understanding different cultures and communicating with more people. I want to learn __________ next.3. 听力题：A solution with a low concentration of ions is called a ______ solution.4. 填空题：A _____ (草原) is filled with wildflowers in spring.5. 听力题：The ______ helps with digestion in the stomach.6. 听力题：The chemical formula for calcium carbonate is ______.7. 听力题：The study of the interactions between matter and energy is called _______.8. 选择题：What do you call the end of a story?A. BeginningB. MiddleC. ConclusionD. Chapter答案: C9. 填空题：The city of Rome is known for its ancient ________ (罗马以其古老的________而闻名).10. 选择题：How many months have 30 days?A. 7B. 8C. 9D. 10答案: A11. 选择题：What do you call a place where animals are kept?A. ZooB. FarmC. AquariumD. Park12. 听力题：The chemical formula for amyl acetate is ______.13. 选择题：What do you call a person who studies rocks?A. BiologistB. GeologistC. ChemistD. Astronomer答案:B14. 选择题：What do we call the act of joining two things together?A. ConnectionB. AttachmentC. BondingD. Linking答案：D15. 选择题：What is the process of taking in oxygen and expelling carbon dioxide?A. PhotosynthesisB. RespirationC. DigestionD. Circulation答案: B16. 选择题：What is the process of water turning into vapor called?A. EvaporationB. CondensationC. PrecipitationD. Sublimation17. 填空题：My cat loves to chase after ______ (昆虫).18. 听力题：I help my mom _____ (洗碗).19. 选择题：What do we call a baby horse?A. CalfB. FoalC. LambD. Kid20. 填空题：A ________ (植物繁殖方法) can differ greatly.21. 听力题：The reaction between an acid and a base produces _____.22. 选择题：What is the capital of Malta?A. VallettaB. MdinaC. RabatD. Birkirkara答案: A23. 选择题：What do we call the traditional Japanese art of folding paper?A. OrigamiB. CalligraphyC. IkebanaD. Sumi-e答案:A24. 选择题：What is the term for the process of water falling to the Earth?A. EvaporationB. PrecipitationC. CondensationD. FiltrationThe teacher is ______ (kind) to all students.26. 填空题：We should _______ (尊重) our elders.27. 听力填空题：I love reading mystery books. My favorite author is __________.28. 选择题：How do you say "goodbye" in Japanese?A. SayonaraB. KonnichiwaC. ArigatoD. Adiós29. 听力题：The dog is ________ to the park.30. 听力题：A lizard can be found ______ on a rock.31. 填空题：The ______ (蜘蛛) spins a web to catch its ______ (昆虫).32. 填空题：The first successful powered flight lasted _______ seconds. (12)33. 听力题：A polar molecule has a slight _____ charge.34. 听力题：The ______ teaches us about animal care.35. 听力题：The capital of Vietnam is __________.36. 选择题：What is the main source of light during the day?A. StarsB. SunC. MoonD. Lamp37. 听力题：I saw a _______ (deer) in the forest.The _______ of a light wave can be affected by its color.39. 选择题：What is the name of the imaginary line that runs from the North Pole to the South Pole?A. EquatorB. Prime MeridianC. International Date LineD. Longitude答案: D40. 填空题：The _____ (藤蔓) climbs up the trellis in my backyard.41. 选择题：What do you call the story of someone's life?A. BiographyB. NovelC. FictionD. Poem答案: A42. 填空题：My sister loves to play with her __________. (玩具)43. 选择题：Which season comes after summer?A. SpringB. WinterC. FallD. Summer答案:C44. 选择题：What do you call the layer of gases surrounding the Earth?a. Hydrosphereb. Biospherec. Atmosphered. Lithosphere答案:C45. 选择题：What is the name of the largest desert in the world?A. SaharaB. GobiC. ArcticD. Antarctic答案:A46. 听力题：She sings _____ (beautifully).47. 填空题：The jackal is a clever ______ (动物).48. 听力题：The Boston Tea Party was a protest against _______ taxes.49. 听力题：A radioactive element has an unstable _______.50. 听力题：She wears _____ (眼镜) to read.51. 填空题：The _____ (蜜蜂) buzzes around the flowers collecting nectar. 蜜蜂在花丛中嗡嗡作响，采集花蜜。
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Ø1000 ethylene units ØDegree of polymerization = 1000 ØIf extended, 1000 ethylene molecules linked together = 252 nm
One conformation of a 2000 carbon polyethylene chain. A. R. 0. Treloar (1958) Physics of Rubber Elasticity
For polyethylene: 200 K vs. 400 K
Glassy solid
(hard, brittle)
Flexible solid
(pliable, rubbery)
Molten polymer
(viscous)
amorphous crystalline
Tg temperature
3. Polymer Molecular Weight
Number of Structural Units
CH2 CH2
MOLECULAR WEIGHT
~[CH2-CH2]n~
POLYMER
MONOMER single compound
•FIXED MW = 28 •each molecule = 28 •If MW ≠ 28, then not ethylene
ØMany polymer properties (viscosity, elasticity, toughness, flexibility) are associated with chain mobility
ØMuch more difficult to “ move”long chains ØLong chains also wrap around each other
12. Polymer Flexibility
ØFlexibility (mobility) involves overcoming entanglements and intermolecular forces
ØChain allowed to twist, turn, rotate, tumble ØAKA … .. segmental motion
ØAmorphous polymers more flexible than crystalline
ØChains not as closely packed ØWeaker intermolecular forces ØGreater mobility
13. Amorphous versus Crystalline
ØChain entanglement
ØChain mobility also affected by side groups and inter-chain (intermolecular) forces
ØMore difficult to move chains with large side groups ØMore difficult to move chains that are strongly attracted to a neighboring chain
•n = VARIABLE •different “molecular” weights result from competing chain growth and termination processes) - probability •n = 500 MW=14,000 n = 550 MW=15,400 n = 600 MW=16,800 ALL are POLYETHYLENE
hydrogen bonding: H CH O H H O H CH cellulosics C N O proteins, nylons
+ δ C O Oδ
dipole-dipole:
+ δ C O Oδ
C N O
δ + δC N + δ δ C N
CH
CH acrylics
polyesters
Ø Each molecule contributes to the average weight relative to its number and its mass (weight)
ØHeavier chains “ worth” more
Ø Weight average more dependent on larger molecules
Fraction
Molecular weight
9. Polymer Molecular Weight
ØHow is molecular weight measured?
ØColligative properties
ØChromatography
10. Mobility and Molecular Weight
1. Polymer Conformations
ØPolymer chains
One conformation of a 150 carbon polyethylene chain
Several conformations of a 13-carbon chain
2. Polymer Conformations
Tm
Tg
~ -80°C ~ -10°C
Tm
105°C ~ 135°C ~ 160°C
Polyethylene Polypropylene
16. Crystallites and Cross-linking
ØCrystallites serve as crosslinks
ØRigid regions linking flexible amorphous areas
Mn =
ΣN1M1 ΣN ΣN1M12 ΣN1M1
ØDetermine Mn and Mw
Mw =
8. Polymer Molecular Weight
ØMolecular weight
ØStatistical nature (probability) of chain growth and termination leads to a range of molecular weights
If polymer chains possess sufficient chemical and geometrical regularity, regions of local order, known as crystallites, can develop. Crystalline and amorphous regions are tightly connected, since one single long polymer chain can run through both regions. crystalline regions “crystallites” amorphous regions
Ø Provides anchoring points Ø Restrains excessive movement Ø Maintains position of chain in network
Øabsorb energy of impact
crystalline region “crystallites”
40000
Richards, J. Appl. Chem., 1951.
18. Polymer Properties
ØWhat are the ideal polymer properties?
ØDepends on polymer’ ultimate use s ØAt the temperature of use, does the polymer need to be . . .
11. Important Forces
ØIntramolecular forces (> 50 kcal/mol)
Ø Covalent bonds in main chain and side groups
ØIntermolecular forces (< 10 kcal/mol)
Ø Dipole-dipole (PVC, PAN, PET) Ø Hydrogen bond (proteins, nylons, polyurethanes) Ø Van der Waals (PE, PP)
STATISTICAL APPROACH yields “AVERAGE” Molecular Weights ‘ Number’ & ‘ Weight’ -Average
4. Polymer Molecular Weight
ØNumber average, Mn
Ø Measures average chain mass Ø The number average mass is primarily dependent on the number of chains of a particular mass Ø Calculated like a “ normal” average or mean
ØBrittle? ØSoft and pliable? ØHard and tough? ØStiff and strong? ØStretchable and resilient?
ØHow do you control these properties?
ØBy controlling the disorder in the chain (amorphous versus crystalline content)
ØMathematically