应用化学专业英语教案

1、专业英语教案teaching plan on specialized english course for applied chemistry课程类型：化学系专业选修课lesson type: specialized course for applied chemistry teaching plan on specialized english course for applied chemistrypart 1 part 2 chemical equationspart 3 chemical calculationpart 4 nomenclature of inorganic chemi

2、calspart 5 some basic chemical theoriespart6 translationpart7 a brief introduction to scientific writing in englishpart 1 颜色颜色 disproportionation neutralization; hydrolysis exothermic reaction endothermic reaction reversible reaction forward reaction reverse reaction spontaneous reaction nonspontane

3、ous reaction 1.反应名称：化化 学学 方方 程程 式式part 2 chemical equations2、反应条件 heat ; burn ignite/ignition electrolyze/electrolysis under/at ambient/room temperature under standard pressure with/in the prescence of catalyst 3、 读 法 3.1 nitrogen reacts with hydrogen to form ammonia at high temperature and pressure

4、 with the presence of a catalyst.n2+ 3h2 高温高压催化剂2nh3 1 mol nitrogen reacts with 3 mol hydrogen to form 2 mol ammonia at high temperature and pressure with the presence of a catalyst. 3.2 nitrogen combines with hydrogen to form ammonia at high temperature and pressure with the presence of a catalyst.

5、 ammonia decomposes to nitrogen and hydrogen at high temperature and pressure with the presence of a catalyst.3.3 reaction between nitrogen and hydrogen at high temperature and pressure with the presence of a catalyst gives ammonia. at high temperature and pressure, reaction of nitrogen with hydroge

6、n in the presence of a catalyst takes place. zinc treated with hydrochloric acid forms hydrogen and zinc chloridezn +2hclzncl2 + h23.4 calcium carbonate when heated produces calcium oxide and carbon dioxide calcium carbonate is heated to yield calcium oxide and carbon dioxide calcium carbonate decom

7、poses to calcium oxide and carbon dioxide when it is heated3.1 化 学 术 语 atomic mass/weight ； molecular weight amount (of substance)； mole number of moles ； molar mass molar volume ； concentration molarity ； excess agent limiting agent ； reactant product ； yieldpart 3 chemical calculation（化学计算化学计算 ）3.

8、2 数学术语： 运算名称 addition substraction mulplication division 动词读法add substract(ed)from multiply(ied)by divide(d)by 介词读法plus minus times over 运算结果 sum difference product quotient 0.001 o/zero point o o one 2/3 two thirds equals/is equal to is approximately equal to less than greater than x2 x squared x3

9、x cubed x-10 x to the minus tenth power 100oc one hundred degrees centigrade 5% five percent (by mass, volume) （） round brackets/parentheses square/angular brackets braces基 本 形 状 linear pyramidal 三角锥的 trigonal tetrahedral 正四面体的 square spherical 球形的 rectangular oval circle planarsteroscopic无机物质的命名par

10、t 4 nomenclature of inorganic chemicalselementcompound4.1 元素和单质的命名元素和单质的命名 “元素”和“单质”的英文意思都是“element”，有时为了区别，在强调“单质”时可用“free element”。因此，单质的英文名称与元素的英文名称是一样的。下面给出的既是元素的名称，同时又是单质的名称。s-block element ia hydrogen lithium sodium potassium rubidium cesium francium iia beryllium magnesium calcium strontium b

11、arium radiumiiia boronaluminiumgalliumindiumthallium iv a carbonsilicongermaniumtinleadv a nitrogenphosphorusarsenicantimonybismuthvia oxygensulfurseleniumtelluriumpoloniumviia fluorinechlorinebromineiodineastatine0heliumneonargonkryptonxenonradonp-block elementcommon transition elememt fe : iron mn

12、 : manganese cu: copper zn: zinc hg: mercury ag: silver au: gold4.2化合物的命名化合物的命名 化合物的命名顺序都是根据化学式从左往右读，这与中文读法顺序是相反的。表示原子个数时使用前缀：mono-di-tri- tetra-penta- hexa- hepta- octa-，nona-,deca-,但是在不会引起歧义时，这些前缀都尽可能被省去。1 化合物正电荷部分的读法化合物正电荷部分的读法直呼其名，即读其元素名称。 如co: carbon monoxide al2o3: aluminium oxide n2o4 ：dinitr

13、ogen tetroxide (tetra-,mono-后缀中的a,o在后一o之前省去) 对于有变价的金属元素，除了可用前缀来表示以外，更多采用罗马数字来表示金属的氧化态，或用后缀-ous表示低价，-ic表示高价。如 feo: iron(ii) oxide 或 ferrous oxide fe2o3: iron (iii) oxide或ferric oxide cu2o: copper(i) oxide 或cuprous oxide cuo: copper(ii) oxide或cupric oxide 化合物负电荷部分的读法：化合物负电荷部分的读法：.二元化合物. 非金属氢化物 . 无氧酸.

14、含氧酸与含氧酸根阴离子. 盐4.2.1二元化合物 常见的二元化合物有卤化物，氧化物，硫化物，氮化物，磷化物，碳化物，金属氢化物等，命名时需要使用后缀-ide，如：fluoride， chloride， bromide， iodide， oxide，sulfide，nitride, phosphide, carbide，hydride; oh -的名称也是用后缀-ide：hydroxide， 非金属氢化物不用此后缀，而是将其看成其它二元化合物（见4.）,非最低价的二元化合物还要加前缀， 如o22-: peroxide o2-: superoxide举例：naf: sodium fluoridea

15、lcl3: aluminium chloride mg2n3: magnesium nitride ag2s： silver sulfide cac2: calcium carbide fe(oh)2：iron(ii) hydroxide 有些物质常用俗称，如no nitric oxide n2o nitrous oxide4.2 非金属氢化物 1)除了水和氨气使用俗称water，ammonia以外，其它的非金属氢化物都用系统名称，命名规则根据化学式的写法不同而有所不同。对于卤族和氧族氢化物，在化学式中写在前面，因此将其看成另一元素的二元化合物。 举例： hf hydrogen fluorid

16、e hcl hydrogen chloride hbr hydrogen bromide hi hydrogen iodide h2s hydrogen sulfide h2se hydrogen selenide h2te hydrogen telluride 2) 对于其它族的非金属氢化物，在化学式中写在后面，可加后缀ane，氮族还可加-ine 举例： ph3: phosphine或phosphane ash3: arsine或arsane sbh3: stibine或stibane bih3: bismuthane ch4: methane sih4: silane b2h6: dibo

17、rane4. 无氧酸命名规则：hydro-词根-icacid 举例： hcl: hydrochloric acid h2s : hydrosufuric acidb boron bor- boride br bromine brom- bromidecl chlorine chlor- chloridef fluorine fluor- fluorideh hydrogen hydr- hydridei iodine iod- iodiden nitrogen nitr- nitrideo oxygen ox- oxidep phosphorus phosph- phosphides sulf

18、ur sulf- or sulfur- sulfidesymbol element stem binary name endings 4. 含氧酸与含氧酸根阴离子 化学专业英语用前后缀的不同组合显示不同价态的含氧酸和含氧酸根阴离子，价态相同的含氧酸及含氧酸根阴离子具有相同的前缀，不同的后缀。高某酸 per-ic 正酸 ic 亚酸 -ous 次酸 hypo-ous高某酸根 per-ate 正酸根 ate 亚酸根 -ite 次酸根hypo-ite其它的前缀还有 ortho-正 meta- 偏 thio-硫代举例：hclo4 perchloric acid clo4- perchlorate ion

19、 hclo3 chloric acid clo3- chlorate ion hclo2 chlorous acid clo2- chlorite ion hclo hypochlorous acid clo- hypochlorite ion h2so4 sulfuric acid h2so3 sulfurous acid hno3 nitric acid hno2 nitrous acid hpo3 metaphosphoric acid s2o32- thiosulfate ion4. 盐正盐正盐：根据化学式从左往右分别读出阳离子和阴离子的名称。 如feso4 iron(ii) sulf

20、ate kmno4 potassium permanganate酸式盐酸式盐：同正盐的读法，酸根中的读做hydrogen，氢原子的个数用前缀表示。如nahco3: sodium hydrogencarbonate 或 sodium bicarbonate nah2po4: sodium dihydrogenphosphate复盐复盐：同正盐的读法，并且阳离子按英文名称的第一个字母顺序读。如 knaco3: potassuim sodium carbonatenanh4hpo4: ammonium sodium hydrogenphosphate水合盐水合盐：结晶水读做water或hydrate

21、如alcl36h2o: aluminum chloride 6-water 或aluminum chloride hexahydrate alk(so4) 212h2o aluminium potassium sulphate 12-water 有机物质的命名有机物质的命名烷烃的英文命名 1）烷烃（）烷烃（alkanes ）有机化合物的英文命名很不统一，有普通命名、有机化合物的英文命名很不统一，有普通命名、衍生命名、系统命名及衍生命名、系统命名及ca系统命名等。系统命名等。ch4 甲烷 methanec2h6 乙烷 ethanec3h8 丙烷 propanec4h10 丁烷 butanec5h

22、12 戊烷pentanec6h14 己烷 hexanec7h16 庚烷 heptanec8h18 辛烷 octanec9h20 壬烷 nonanec10h22 癸烷 decanec11h24 十一undecanec12h26 十二烷dodecanec18h28 十三烷tridecanec14h30 十四烷tetradecanec15h32 十五烷pentadecanec16h34 十六烷hexadecan烷烃的英文名称字尾都有烃的英文名称字尾都有-ane 2 不饱和烃不饱和烃unsaturated hydrocarbonch3甲 基 methyl methylch3ch2乙 基 ethyl e

23、thylch3ch2ch2正丙基n-propyl propyl异丙基isopropyl (1-methyl ethyl)ch3ch2ch2ch2 正丁基n-butyl butylch3(ch2)3ch2 正戊基n-pentyl或n-amyl pentyl异戊基isopentyl或isoamyl (3-methyl butyl)新戊基neopentyl (2,2-dimethyl propyl)烷基的名称烷基的名称 ch2=ch2 乙 烯 ethylene ethylene,ch3ch=ch2 丙 烯 propylene propene,1丁烯1-butylene 1-butene,(ch3)2

24、c=ch2 异丁烯isobutylene propene, 2methylch3ch2ch2ch=ch2 1戊烯1-amylene 1-pentene,异戊二烯isoprene 1,3butadiene,2-methyl-烯基（alkenyl）是将烯的字尾-ene 改为-enyl。烯类化合物的名称烯类化合物的名称烯基的名称ch2=ch 乙烯基vinyl ethenyl烯丙基allyl (2-propenyl)丙烯基propenyl (1-propenyl)2-丁烯基(2-butenyl)炔类化合物的名称炔类化合物的名称hcch 乙炔 acetylene ; ethyne,ch3cch 丙 炔

25、methyl acetylene ;propyne,2丁炔dimethyl acetylene;2-butyne,丙烯基乙炔propenyl acetylene;3-penten-1-yne,系统命名是以芳香环为母体，取代基根据环上的位置而定位，苯环上表示2个基团的相对位置普通命名常用邻o,对p，间m表示 芳香烃芳香烃aromatic hydrocarbon compounds苯 benzene,萘 naphthalene ,蒽 anthracene ,菲 phenanthrene ,甲苯 toluene; methyl- benzene邻二甲苯o-xylene; 1,2-dimethyl-b

26、enzene对二甲苯p-xylene; 1,4-dimethyl-benzene间二甲苯m-xylene; 1,3-dimethyl-benzene苯乙烯styrenestyrene;ethenyl-benzxene卤代烃卤代烃organic halidesch3cl 氯甲烷methyl chloride; chloro-methanech2cl2 二氯甲烷methylene dichloride;dichloro-methanechcl3三氯甲烷（氯仿） chloroform; trichloro- methaneccl4 四氯化碳carbon tetrachloride; tetrachl

27、oro- methanech3ch2br 溴乙烷ethyl bromide;brormo- ethane1,2二溴乙烷ethylene dibromide;1,2-dibromo- ethanech2=chcl 氯乙烯vinyl chloride; chloro- ethylenech2=ch-ch2cl 烯丙基氯allyl chloride;3-chloro-1-propene氯 苯 phenyl chloride; chloro-benzene二氯苯p-phenylene dichloridebenzene, 1,4-dichlorop-dichlorobenzene5 醇、酚、醚醇、酚、

28、醚alcohols, phenols and ethersch3oh 甲醇 methyl alcohol; carbinol methanol,c2h5oh 乙醇 ethyl alcohol; carbinol ethanol,ch3ch2ch2oh 正丙醇n-propyl alcohol;ethyl carbinol 1-propanol,异丙醇isopropyl alcohol;dimethyl carbinol 2-propanol,ch2(ch2)3oh 正丁醇n-butyl alcohol; propyl carbinol 1-butanol,苯甲醇(苄醇) benzyl alcoh

29、ol;phenylmethanol,醇的英文名称醇的英文名称 苯苯 酚酚 phenol, -萘酚萘酚-naphthol ;1-naphthalenol,-萘酚萘酚-naphthol ; 2-naphthalenol,对甲苯酚对甲苯酚p-cresol phenol, 双酚双酚a bisphenol a; 1-methylethylidene bis-phenol, 酚的英文名称酚的英文名称ch3ch2och2ch3 乙乙 醚醚 diethyl ether或或ethyl ether, 1,1-oxybis-ethanech3och2ch2ch2ch3 甲丁醚甲丁醚n-butyl methyl et

30、her, 1-methoxy-butane苯甲醚苯甲醚methyl phenyl ether或或methoxy-anisole 醚的英文名称醚的英文名称烷氧基的英文名称烷氧基的英文名称ch3o- 甲氧基甲氧基methoxy c2h5o- 乙氧基乙氧基ethoxyc3h7o- 丙氧基丙氧基propoxy 含氮有机化合物含氮有机化合物(nitrogenous organic compounds)ch3nh2 甲甲 胺胺 methyl amine;methanamine,ch3nhc2h5 甲乙胺甲乙胺ethyl methyl amine; n-methyl-ethanamine醛和酮醛和酮alde

31、hydes and ketones醛和酮醛和酮aldehydes and ketonesch2o 甲醛甲醛 formaldehyde,ch3cho 乙醛乙醛 acetaldehyde,ch3ch2cho 丙醛丙醛 propionaldehyde;propanal,ch3ch2ch2cho 正丁醛正丁醛n-butyraldehyde;butanal,ch3(ch2)3cho 正戊醛正戊醛n-valeraldehyde;pentanal,-甲基丁醛甲基丁醛-methyl butyraldehyde;2-methyl- butanalch2=chcho 丙烯醛丙烯醛acrolein 2-propen

32、al,丙丙 酮酮 acetone; 2-propanone,acetone2-戊酮戊酮methyl propyl ketone 2-pentanone,环己酮环己酮cyclohexanone cyclohexanone,二苯酮二苯酮diphenyl ketone benzophenone methanone, diphenyl-羧酸和取代酸羧酸和取代酸carboxylic acids and substitute carboxylic acidshcooh 甲酸甲酸 formic acid,ch3cooh 乙酸乙酸 acetic acid,ch3ch2cooh 丙酸丙酸 propionic a

33、cid,ch3(ch2)2cooh 正丁酸正丁酸n-butyric acid;butanoic acid,ch3(ch2)3cooh 正戊酸正戊酸n-valeric acid;pentanoic acid,ch3(ch2)4cooh 正已酸正已酸n-caproic acid; hexanoic acid,乳乳 酸酸 lactic acid; 2-hydroxy-propanoic acidch2=chcooh 丙烯酸丙烯酸acrylic acid;2-propenoic acid,草草 酸酸 oxalic acid; ethanedioic acid,丙二酸丙二酸malonic acid; p

34、ropandioic acid,已二酸已二酸adipic acid; hexanedioic acid,顺顺-丁烯二酸丁烯二酸maleic acid; z-2-butenedioic acid, 反反-丁烯二酸丁烯二酸fumaric acid; e-2-butenedioic acid, 苯甲酸苯甲酸benzoic acid; benzoic acid,part6 translation(english-chinese and chinese-english)i.important role of translation translation is a rendering from one

35、language into another,i.e., the faithful representation in one language of what is written orsaid in another language. as ameans of communication, translation play an important role in human civilization. in the west, literary translation can traced back to300 bc, while in china, recorded translatio

36、n activities are even earlier, dating from the zhou dynasty(1100bc).hower, not until recent centuries,especially by the end of the 19th century did systematic study of translation get underway. in the past decadestranslation theories and activities have developed fast at home and abord. a morden soc

37、iety sees an extensive use of translation on various occasion. if a foreign language is generlly accepted as a tool of life, translation then obviously serves as a dynamic means of emplooying this tool. a proper and dexterous translation helps to promote mutual understanding between pepoles of diffe

38、rent cultural and social backgrounds, whereas a misunderstanding or improper rendering of words or expressions may lead to confusion.nature and scope of translation what is translation? some people believe it is a science, others take it as an art; and yet many consider it a craft, or rather, a skil

39、l. of these varied opinions, which one holds true for our purpose? if it refers to a subject, namely, the study of translation theory and skills, it is no doubt a science, if it refers to some specific pieces of translation, then it is more like a n art, if it refers to a process, in which something

40、 is translated, then we may regard it as a craft or a skill. translation covers a very broad range. in terms of languages ,it can be divided into two categories: from native languages into foreign languages and vice versa; in terms of the mode, it can be divided into oral interpretation, written tra

41、nslation and machine translation; in terms of materials to be translated, there is translation of scientific materials, translation of literary works such as novels, poety drama, etc., translation of political essays such as treatises on social problems, reports, speeches, etc., in terms of disposal

42、, it can be either full-text translation, abridged translation or adapted translation.principles and criteria of translation the so-called principles and criteria of translation are actually the two sides of the samething. the former lays emphasis on the translator; while the latter on the reader or

43、 critic. yan fus “three-character guide”: faithfulness, expressiveness and elegance.literal translation and free translation the so-called literal translation, generally speaking, means “not to alter the original words and sentences”; strictly speaking, it strives “to keep the sentiments and style o

44、f the original”. free translation is an alternative approach which is used mainly to convery the meaning and spirit of the original without trying to reproduce its sentence patterns or figures of speech. 1. theres no pot so ugly it cant find a lid 2. little fish does not eat big fish3. what the tong

45、ue says, the neck pays for4. what was hatched a hen must not try to be a rooster5. a gift is the key to open the door closed agaist you. translation techniques generally speaking, the basic translation techniques that merit our attention and that are to be applied in english-chinese and chinese-engl

46、ish translations include:(1)diction(2)amplification(3)omission(4)repetition(5)conversion(6)restructuring(7)negation(8)division科技英语的写作科技论文中文写作科技论文英文写作科技论文的写作明确所研究的方向设计实验着手实验撰写论文科技论文的中文写作写作步骤3结论2结果与讨论1实验部分引言作者及单位题目参考文献摘要作者为几个单位的，请在右上角用上标形式标出去，姓名间空一格，作者单位标至二级单位，单位间用分号隔开； 作者及单位示例（注意项目、顺序、英文大小写、标点符号）示例（注

47、意项目、顺序、英文大小写、标点符号） 离体培养条件下半夏叶柄形成珠芽过程中内源激素的变化* 常 莉1) 徐有明1) 薛建平2)*(1)华中农业大学园艺林学学院，武汉 430070；2）安徽省淮北煤炭师范学院生物系，淮北 235000)首页面脚注示例（注意项目、顺序及标点符号）首页面脚注示例（注意项目、顺序及标点符号）*国家农业成果转化基金(05efn213400124)和淮北市重点项目(06125)资助*通讯作者. e-mail: 常莉,女,1981年生, 华中农业大学园艺林学学院硕士研究生,武汉 430070赵铭钦，男，1964年生，副教授.工作单位: 河南农业大学农学院,国家烟草栽培生理生

48、化基地,郑州 450002. e-mail: 中文摘要为报道式摘要，包括简要介绍研究目的、 材料、方法和结论，结果要求详细 。摘要关键词间用分号隔开，分号后空半格。 关键词摘要示例摘要示例 为研究黄花蒿生长发育过程中青蒿素含量的动态变异特性，对黄花蒿生长发育过程中青蒿素含量的变化进行了研究，实验表明：黄花蒿下部叶中青蒿素含量明显高于中、上部；黄花蒿上午采收样青蒿素含量明显高于下午；时间越长，青蒿素的含量越黄花蒿生长高；黄花蒿在整个的生长发育过程中，从营养生长末期到花蕾期，青蒿素含量有递增趋势，开花后青蒿素含量明显下降。关键词：黄花蒿；青蒿素；动态变异；含量摘要：为了探讨不同穗型品种水稻的穗部性

49、状与产量和稻米品质的关系（表示目的），以辽宁省近年育成的水稻品种（品系）为试材（交待材料），（必要时介绍方法）进行了品种类型间的比较研究。结果表明：根据水稻着粒密度可将试材分为散穗型、半散穗型、半紧穗型和紧穗型四种类型。各类型间稻谷产量差异显著，其中半散穗型和半紧穗型品种产量较高。紧穗型品种的一次枝梗数、二次枝梗数和每穗空秕粒数都较多，成粒率较低。除了散穗型品种整精米率显著高于半散穗型和半紧穗型品种外，散穗型、半散穗型和半紧穗型间其它品质性状差异不显著，三者品质明显好于紧穗型品种。着粒密度与每穗成粒数、产量呈抛物线，与碱消值呈显著负相关，与谷草比呈显著正相关；产量与食味值呈显著的正相关。在籽粒

50、灌浆结实期，半散穗型和半紧穗型品种的单叶净光合速率较高，后期生产的干物质较多，谷草比较大（明确介绍结果）。半紧穗型和半散穗型品种在产量较高，食味品质较好，选择适宜着粒密度的材料，容易育出高产优质品种（得出结论）。 包括研究的重要意义、前人研究进展、研究切入点及拟解决的关键问题。 前言前言示例：前言示例：【本研究的重要意义】穗型是株型的重要组成部分，是水稻的重要形态特征之一，随着水稻穗型由弯到直，穗型与稻米品质的协调关系已成为日益重要的研究内容1-3。【前人研究进展】徐正进等4按颈穗弯曲角度划分为直立、半直立和弯曲3种穗型；周开达等5按单穗重划分为重穗型、中穗型和轻穗型；yamamoto6等按着

51、粒密度划分为紧穗型、半紧穗型、半散穗型和散穗型。徐正进等按穗型指数2（pti）划分为上部优势型、中部优势型和下部优势型。穗部性状与结实率7，与碾米品质8 、物质积累与分配9，籽粒灌浆特性10以及产量潜力11关系密切。【本研究切入点】近年来，随着水稻品种产量不断提高和要求品质的改善，介于紧穗型和散穗型之间的中间类型有增加的趋势。【拟解决的关键问题】本文以辽宁省近年育成的水稻品种（品系）为材料，对以着粒密度为指标，对不同穗型品种的穗部性状和稻米品质进行探讨。旨在探索穗型分类与指标，为水稻产量提高和品质的改良提供理论依据。 有机磷农药作为高效杀虫剂, 对蔬菜、稻米、瓜果生长作出了巨大贡献,但是,这些

52、农药对水体和生态环境的污染也日益严重，这些污染影响了人类的生存,它对人畜毒性较大,近年来许多食物中毒事件都是由于有机磷等农药残留所引起的,农药残留严重威胁着人类健康。目前除了推广使用低毒农药外, 研究此类农药的有效降解方法也有重要意义。近年来逐渐发展起来的光催化降解技术为这一问题的解决提供了良好的途径1-2。 二氧化钛(tio2)光催化降解技术是近年来逐渐发展起来污染治理的技术之一。tio2在环保方面的突出优点就是活性高、稳定性好、对人体无害、过量使用也不会引发污染问题，成为最受欢迎的一种光催化剂，被称为“绿色”的污染治理技术3-4。tio2及其改性物对农药的催化作用在国内较少报道,尤其是稀土

53、改性的tio2对农药降解的相关报道甚少,本文研究了铒掺杂tio2对甲胺磷的光催化降解的影响。科技论文的英文写作写作步骤4.conclusion3.rusults and discussion2.experimental section1.introductionauthor and his worktitlerefferenceabstractfigure captionsacknowledgement figures tables keep these in mind when you read what is the major question addressed in this pap

54、er? is this question important and why? what are the approaches used in this paper, and whether they are adequate for the questions?what are the novel idea or using innovative approaches? what is the concept coming out of this paper? do the results presented support this new concept?how to read scie

55、ntific papers?how to read scientific papers?titles important/significant unexpected/unusual function mechanisms straight forward rationale “remain unknown”; “to determine” summary statement “here we show” body dont go into details; dont use many special termsabstractstudy on dynamic variance charact

56、er of arteannuin content in artemisia annual1）department of chemistry and chemical engineering, huaihua university, huaihua 418008)2）the key laboratory of hunan province for the study and utilize of ethnomedicinal plant resources, huaihua 418008)abstract in this paper, the dynamic variance characteri