工学Lesson2专业英语

上传人:新** 文档编号:567315553 上传时间:2024-07-19 格式:PPT 页数:34 大小:1.05MB
返回 下载 相关 举报
工学Lesson2专业英语_第1页
第1页 / 共34页
工学Lesson2专业英语_第2页
第2页 / 共34页
工学Lesson2专业英语_第3页
第3页 / 共34页
工学Lesson2专业英语_第4页
第4页 / 共34页
工学Lesson2专业英语_第5页
第5页 / 共34页
点击查看更多>>
资源描述

《工学Lesson2专业英语》由会员分享,可在线阅读,更多相关《工学Lesson2专业英语(34页珍藏版)》请在金锄头文库上搜索。

1、 工学工学Lesson-2Lesson-2专业英语专业英语Contents无机化合物命名 Inorganic Chemical NomenclatureUnit 3逐步聚合反应 Step -Growth Polymerization2024/7/19无机化合物命名 (Inorganic Chemical Nomenclature)1、元素命名(元素周期表)(Periodical Table)2024/7/19A doubly charged molecule containing two atoms of sulfur, each atom having the atomic number 1

2、6 and mass number 322024/7/19Names and Symbols(符号符号) for Some Chemical Elements2024/7/192024/7/19For the naming of compounds of metals (oxides, hydroxides and salts) in which the metal may exhibit more than one oxidation state: The oxidation state of the metal is shown by a Roman numeral in parenthe

3、ses immediately following the English name of the metal which corresponds to its oxidation number. No numeral is used if the metal has only one common oxidation numbere.g. NaCl: sodium chloride; Al(OH)3: aluminum hydroxide FeBr2: iron (II) bromide; Cr2(SO4)3: chromium (III) sulfate2024/7/19如果如果不用罗马数

4、字不用罗马数字表明其价态,也可用离子的名称表明其价态,也可用离子的名称表示表示e.g. FeCl2 : ferrous chloride (iron (II) chloride) FeCl3: ferric chloride (iron (III) chloride)2024/7/19Some Common Ions(共离子)(共离子) (Cation)2024/7/19Some Common Ions (Anion)2024/7/19Naming nonmetal oxidesUsing the Greek prefixes for both the number of oxygen ato

5、m and that of the other element in the compoundsThe prefix used are: (1) mono- (mon-); (2) di-; (3) tri-; (4) tetra-; (5) penta-; (6) hexa-; (7) hepta; (8) octa-; (9) nona-; (10)deca-. Generally the letter “a” is omitted from the prefix (from tetra on) when naming a nonmetal oxide and often “mono-”

6、is omitted from the name altogether 2024/7/19Name of some nonmetal oxides2024/7/192024/7/192024/7/19Acid salt (Acid containing acid hydrogen)Names are formed by adding the word “hydrogen”, with numerical prefix when necessary, to denote the replaceable hydrogen in the salt. Hydrogen should be follow

7、ed without space by the name of the anionAnion: 阴离子;阴离子;Cation: 阳离子阳离子e.g. NaHCO3 : sodium hydrogencarbonate (sodium bicarbonate);LiH2PO4 : lithium dihydorgenphosphate;Na2HPO4 : Disodium hydrogenphosphate2024/7/19ExercisesH2S; HNO3; Ca(OH)2; NaH2PO4;Potassium acetate; Trisodium phosphate;Sulfurous a

8、cid; Sodium sulfite;P2O5; NaHCO3;MgSO4; BaCl2; NaClO3; 亚氯酸钾亚氯酸钾 Hydrochloric acid; Ar五聚体;五聚体; 六聚体;六聚体; 结晶;结晶; 苯磺酰胺苯磺酰胺1. Translate the words into English or Chinese2024/7/192. Translate the following into EnglishBe careful with that bottle. Its cyanide. a hard ferromagnetic silver-white bivalent or

9、trivalent metallic element; a trace element in plant and animal nutrition.a white powder comprised of calcium hydroxide, chloride, and hypochlorite and used to bleach and/or disinfect. The conversion of nitrite is slowed down as contrasted to the conversion of ammonium ions to nitrite. As the chlori

10、de ion and in the hypochlorite ion, it has valence 1; in the chlorite, chlorate, and perchlorate ions, it has higher valences.2024/7/19UNIT 3 Step -Growth Polymerization逐步聚合反应逐步聚合反应 Many different chemical reactions may be used to synthesize polymeric materials by step-growth polymerization. These i

11、nclude esterification, Amidation, the formation of urethanes (氨基甲酸氨基甲酸酯酯), aromatic substitution, etc. Polymerization proceeds by the reactions between two different functional groups, e. g., hydroxyl and carboxyl groups, or isocyanate and hydroxyl groups.Proceed with: “继续进行,重新进行继续进行,重新进行”e.g. Pleas

12、e proceed with your work.科技英语特点:大量的专有名词科技英语特点:大量的专有名词2024/7/19All step-growth polymerizations fall into two groups depending on the type of monomer (s) employed. The first involves two different polyfunctional monomers in which each monomer possesses only one type of functional group. A polyfunction

13、al monomer is one with two or more functional groups per molecule. “Fall into”: 分为(几类);属于;落入分为(几类);属于;落入All changes of matter may fall into two broad classes: physical and chemical changes.2024/7/19“Fall into disuse” 停止使用停止使用First of all, this method has fallen into disuse (out of use).“Fall off”: 衰

14、落,减少,下降衰落,减少,下降The demand for the chemical has fallen off.“Fall short of ”未达到,缺乏未达到,缺乏The result fell short of our expectation.“Fall under” 归入归入类,属于类,属于This subject falls under the head of chemistry.“Fall to (sink to)”下降到下降到In 1933, industrial output in the USA fell to 65 percent of the output in 19

15、29.2024/7/19The second involves a single monomer containing both types of functional groups. The synthesis of polyamides illustrates both groups of polymerization reactions. Thus, polyamides can be obtained from the reaction of diamineswith diacids or from the reaction of amino acids with themselves

16、2024/7/19The two groups of reactions can be represented in a general manner by the equations as followsReaction (3. 1) illustrates the former, while (3. 2) is of the latter type. (并列分句并列分句)2024/7/19Polyesterification, whether between diol and dibasic acid or intermolecularly between hydroxy acid mol

17、ecules, is an example of a step-growth polymerization process. The esterification reaction occurs anywhere in the monomer matrix where two monomer molecules collide, and once the ester has formed, it, too, can react further by virtue of its still-reactive hydroxyl or carboxyl groups. The net effect

18、of this is that monomer molecules are consumed rapidly without any large increase in molecular weight. “By virtue of ” 依靠依靠的力量,由于的力量,由于Whether与与if的区别的区别Whether 和和if 作作“是否是否”讲时,均可引导从句。讲时,均可引导从句。但但Whether可引导主语从句,表语从句,宾语可引导主语从句,表语从句,宾语从句,同位语从句,而从句,同位语从句,而if只能引导宾语从句只能引导宾语从句Once引导时间状语从句,by vitue of 是主句的方

19、式状语2024/7/19Whetheror not; whether or not; whether or no; whether or noI. Whether 可用于可用于“疑问词疑问词whether+不定式不定式”结构,结构,if则则不能不能 (infinitive)It is not yet decided whether to do this work at the very start. (一开始一开始)II. Whether 引导主语从句,引导主语从句,if则不能则不能Whether the materials could stand the test is still a qu

20、estion.III. Whether或或if均可引导宾语从句均可引导宾语从句(1). So far there has been no news about whether they havearrived there.(2). We dont know whether (if) it is right.2024/7/19IV. Whether引导表语从句,引导表语从句,if则不能则不能The question is whether he should have a low opinion of this test.V. Whether 引导同位语从句,引导同位语从句,if则不能则不能The

21、y asked him the question whether an electric current can be produced by magnetism.VI. Whether引导让步从句引导让步从句 (concessive clause)These working conditions are applicable whether the product is pure or not.“Whether or no”引导名词从句时,作引导名词从句时,作“是否是否”讲,不引讲,不引导从句时,作导从句时,作“无论如何无论如何”讲讲Whether or no they designed t

22、his kind of machine, I dont know I should do it, whether or no.2024/7/19主句中不缺少主语、宾语或表语时,主句中不缺少主语、宾语或表语时,whether引导的为引导的为让步从句:让步从句:All substances, whether they are (be) gaseous, liquid or solid, are made up of atoms.让步从句省略让步从句省略“Whether”时,谓语用原形动词时,谓语用原形动词 (一般一般为为be),主语、谓语颠倒,主语、谓语颠倒All magnets (磁体)(磁体)

23、behave the same, be they large or small. Be it so, we must continue to do the test.2024/7/19Fig.3.1 illustrates this phenomenon. Assume, for example, that each square in Fig. 3.1 represents a molecule of hydroxy acid. After the initial dimer molecules form (b), half the monomer molecules have been c

24、onsumed and the average degree of polymerization (DP) of polymeric species is 2. As trimer and more dimer molecules form (c), more than 80% of the monomer molecules have reacted, but DP is still only 2. 5. “Assuming (that)”:假定:假定When a beaker of water is heated from below the water at the bottom bec

25、ome less dense (assuming it is above 4) and rises.2024/7/19Fig. 3.1 Schematic diagram(示意图)(示意图) of step-growthpolymerization (a) Unreacted monomer; (b) 50% reacted; (c) 83.3% reacted; (d) 100% reacted; (Dotted lines represent reacting species)2024/7/19When all the monomer molecules have reacted (d),

26、 DP is 4. But each polymer molecule that forms still has reactive end groups; hence the polymerization reaction will continue in a stepwise fashion, with each esterification step being identical in rate and mechanism to the initial esterification of onomers.“Identically equal to”: 恒等于恒等于The force ac

27、ting on the air is identically equal to the mass of air times its acceleration.2024/7/19Thus, molecular weight increases slowly even at high levels of monomer conversion, and it will continue to increase until the viscosity build-up makes it mechanically too difficult to remove water of esterificati

28、on or for reactive end groups to find each other.“Until” 到到为止(肯定句),直到为止(肯定句),直到以前(否定句)以前(否定句)(1) They work from 6 oclock in the morning until 2 oclock in the afternoon.(2) A body at rest will never move until a force compels it.“It was not until”Not until主语和谓语颠倒,但主语和谓语颠倒,但until引出的从句无颠倒情况引出的从句无颠倒情况It

29、 was not until 1959 that chemists succeeded in obtaining this compound.Not until the instrument was repaired did we begin the experiment.2024/7/19It can also be shown that in the AA + BB type of polymerization, an exact stoichiometric balance is necessary to achieve high molecular weights. If some m

30、onofunctional impurity is present, its reaction will limit the molecular weight by rendering a chain end inactive. Similarly, high-purity monomers are necessary in the AB type of poly condensation, and it follows that high-yield reactions are the only practical ones for polymer formation, since side reactions will upset the stoichiometric balance.Stevens M P. Polymer Chemistry. London: Addison-Wesley Publishing Company, 1975. 13“It follows that”: 由此可见由此可见It follows that the greater the conductance a substance has, the less is the resistance.2024/7/192024/7/192024/7/19结束!结束!

展开阅读全文
相关资源
正为您匹配相似的精品文档
相关搜索

最新文档


当前位置:首页 > 办公文档 > 工作计划

电脑版 |金锄头文库版权所有
经营许可证:蜀ICP备13022795号 | 川公网安备 51140202000112号