众文网1.化学专业毕业论文摘要翻译
我是机器和人一起帮你翻译的，希望对你有所帮助 According to the law according to one - Bill, after one layer of thickness of wavelength, liquid is fixed, suck the luminosity proportional to density of the coloured material. This experiment is to formulate the serial sulphur base salicylic acid of pH4.5-4.8 copper solution by waiting for one Mole of serial laws to determine, among them the sulphur base salicylic acid and quantity of the copper ion and total material do not change, but one Mole of marks of the two is changed continuously. Measure the luminosity of sucking of this line of materials with the spectrophotometer. One Mole of marks sucks the luminosity as the ordinate as the abscissa with sulphur base salicylic acid, make the luminosity of sucking to make up and pursue. It is matching the composition of the thing to make up with sucking the solution of the luminosity with corresponding maximum. Calculate with relation that is sucked between the luminosity, apparent stability constant through the ionization degree, can get the apparent stable constant of copper sulphur base salicylic acid. It's time, it tests to be typical comprehensive, experiment of designing etc., it comprehensive volumetric analysis basic operation skill, spectral analysis, chemical literature consult method knowledge, have designing nature, probing into characteristic. It analyze volumetric analysis with modern instrument technology use for, determine steady constant to cooperate the thing, comprehensive volumetric analysis, spectral analysis, experiment are operated and the computer technology combine together. Thus improve students' practice ability in many aspects. Method of experiment this very simple fast, need complicated instrument can determine composition and form to cooperate thing Watch the constant of stabilizing. Offer certain reference material for cooperating with the research of the thing. Key word: Cooperate with things, make up, stabilize the constant apparently, wait for one Mole of serial laws。
2.化学毕业论文中文摘要翻译
In organic synthesis because of some reaction of the synthesis by conventional hard to achieve the desired purpose or relatively complicated, so rearrangement is an effective way. Rearrangement reaction of high efficiency and high stereoselectivity. I passed a lot of relevant information available on the molecular rearrangement of the benzidine rearrangement reaction. To o-nitrotoluene as the raw material, after a two-step chemical reaction synthesis of 3,3 `- dimethyl benzidine: o-nitrotoluene in alkali zinc under conditions of 81 ~ 84 degrees Celsius in the range of 5 hours reaction, reduction of 2,2 `- DNPH; 2,2` - DNPH with 10% hydrochloric acid in the range of 0 to 5 degrees within two hours reaction, and then at room temperature (20 ~ 25 degrees) reaction 3 hours, to be `3,3 - dimethyl benzidine, a product for the gray solid, 45.5 percent yield.。
3.化学毕业论文中文摘要翻译
In organic synthesis because of some reaction of the synthesis by conventional hard to achieve the desired purpose or relatively complicated, so rearrangement is an effective way. Rearrangement reaction of high efficiency and high stereoselectivity. I passed a lot of relevant information available on the molecular rearrangement of the benzidine rearrangement reaction.
To o-nitrotoluene as the raw material, after a two-step chemical reaction synthesis of 3,3 `- dimethyl benzidine: o-nitrotoluene in alkali zinc under conditions of 81 ~ 84 degrees Celsius in the range of 5 hours reaction, reduction of 2,2 `- DNPH; 2,2` - DNPH with 10% hydrochloric acid in the range of 0 to 5 degrees within two hours reaction, and then at room temperature (20 ~ 25 degrees) reaction 3 hours, to be `3,3 - dimethyl benzidine, a product for the gray solid, 45.5 percent yield.
4.化学论文摘要翻译,谢谢
Research in safflower Flavonoids, the use of ethanol extract of saffron soaked in the chemical composition. To extract a qualitative analysis that is contained in saffron Flavonoids. Of our predecessors by improving extraction technology, used solid-phase extraction way to extract a separation, that is, the AB-8 macroporous resin for solid phase, ethanol - water eluate, through multiple-eluting And constantly improve the preparation of conditions, from the extract of red flowers in the isolated flavonoids components. Methanol as mobile phase, with high-performance liquid chromatography to extract flavonoids component in the test, have two peak. Note AB-8 macroporous resin is a good performance of flavonoids Adsorbent, and the use of solid-phase extraction method largely avoid the use of toxic and harmful organic Chemistry, for brevity, and high yield.。
5.化学毕业论文摘要翻译
The actual state, hazards, and prevention and comprehensive treatment of "White Pollution"
Abstract: The invention of plastic bag brings people lots of convenience. However, with widespread use and lack of environmental awareness, plastic bags have generated some hazards to the life of human. Along with the development of economy, "White pollution" has been becoming a public nuisance. which negatively affect the sustainable development. China has employed various manners to prevent and treat it to return the green to earth again.
Key words:"White pollution", actual state in our country hazard, reasons of formation, prevention manners, comprehensive treatment
6.以“萃取XX”为题 写一篇500字的论文 （化学）
摘要：研究了运用固相微萃取/GC/ECD直接萃取溅定水中的三种氯酚的方法，得到了分析三种氯酚的SHE最佳萃取条件；选取聚丙烯酸酯（PA）萃取头，水溶液调pH=2，并用NaCl饱和，室温下在持续磁力搅拌下直接萃取40min，纤维萃取头在260℃脱附5min。
所建立的方法适于快速、方便地测定水中三种氯酚，无须浓缩和预处理。 1 引言 固相微萃取是九十年代发展起来的一种快速、省时、高效、操作简便的样品前处理技术。
它克服了以往预处理方祛的诸多不足，集采集、浓缩于一体，简单、方便、无溶剂，不会造成二次污染，是一种有利于环保的很有应用前景的预处理方法。萃取装置使用涂有色谱固定相或吸附剂的熔融石英纤维管（简称为萃取头），和外套不锈钢管加以保护，形状像一支色谱进样针，可方便地与气相色谱、液相色谱、色谱/质谱等仪器联用。
它携带方便，可以直接从液体和气体中取样然后分析，已广泛用于环境样品的分析中[4][5][6][7]。 氯酚类化合物是环境（水和土壤）中重要的污染物，其中2,4-氯苯酚（以下简称DCP）、2,4,6三氯苯酚（以下简称TCP）和五氯苯酚（以下简称PCP）已被我国列为水体中优先控制污染物。
目前，对酚类化合物的分析主要是采用液-液萃取法，如美国EPA方法中的604[8]和[9]，以及后来发展起来的固相萃取法（SPE）。液-液萃取的主要缺点是多步、费时，而且需要大量价格较高并对健康有害的高纯有机溶剂。
SPE方法尽管同液-液萃取相比有了很大的改进，但仍是多步过程，且对半挥发性化合物的萃取受到方法本身的限制。本研究利用固相微萃/GC/ECD方法对水中这三种氯酚进行了分析，并讨论了各种实验条件对分析结果的影响，结果表明该方法快速、简单、准确，适合水中上述三种氯酚的分析。
2 实验部分 2.1 仪器与试剂 惠普5890型气相色谱仪（配电子捕获检测器）；固相微萃取装置（加拿大Supelco公司，萃取头为85μm膜厚的聚丙烯酸酯固相涂层针头） 2,4-二氯苯酚、2,4,6-三氯苯酚、五氯苯酚色谱纯晶（购于Pure Chemical Analysis Lt.Co.）;0.2mol.L-1HCI：氯化钠（分析纯）；甲醇（色谱纯）；无酚水（500ml蒸馏水加入5ml10%的NaOH和少量KMn04加热蒸馏，取馏出液。） 2.2 色谱条件 色谱柱：HP公司HP-5MS 31m*0.32mm*0.25μm石英毛细管柱；进样口温度：260℃；柱温：60℃（4min）—260℃（3min），升温速率8℃/min;ECD检测器温度：280℃；载气流速：高纯氮，3.3ml/min；无分流进样。
2.3 固相微萃取条件与过程 在100ml容量瓶中预先加入6.5ml0.2mol.L-1的HCl，再加入定量的氯酚标准溶液，并用无酚水稀释至刻度。取10ml（总容积约为12ml）洁净顶空瓶（带铝封盖和内衬聚四氟乙烯膜的密封垫），加入过量固体NaCl（约4g）和磁力棒，再加入配制好的标准待测样品10.0ml，立即加盖密封压紧，将顶空瓶置于磁力搅拌仪上，启动搅拌，然后在常温下从瓶盖上方直接插入针管（注意针管套不要接触瓶内液面），推下手柄活塞杆，使萃取头完全浸入溶液中，保持40min。
萃取时间到达后，取出针管，立即插入气相色谱进样口进行热解析5min。 3 结果与讨论 3.1 测定结果 3.2 萃取涂层的选择 目前应用较多的三种多聚物涂层百非极性的聚二甲基硅氧烷（PDMS）和极性的聚丙烯酸酯（PA）或聚乙二醇（PEG）[4]。
PDMS涂层通常用于非极性化合物的分析，PA涂层通常用于中极性化合物的分析，我们比较了同一氯酚混标样在PDMS和PA两种不同萃取头作用下的测定结果（见图3），结果表明PA萃—取头对酚类的萃取效果更好[9]。 3.3 萃取平衡时间对萃取量的影响 由于待测物分子从溶液中向固相涂层的传质速度比较慢[3]，所以直接萃取要求的时间要相对长一些。
表1所示为三种氯酚在不同萃取时间下萃取量的影响。实验表明，平衡时间越长，SPME萃取量越大，40min以后萃取量基本上不随时间的延长而增大，表明萃取过程达到了平衡，故本实验取平衡时间为40min。
3.4 酸度对萃取量的影响 三种氯酚均属于弱酸，其离解常数pka如下：2,4-DCP(pka =7.85),2,4,6-TCP(pka=7.42),PCP(pka=4.74)，在pH为中性的溶液中，氯酚都有离解，能形成离子状态，不利于萃取。降低pH值，能使它们的电离受到抑制，以保持氯酚的分子状态，使其在固相涂层上有更大的亲和力，从而增加萃取量，同时也提高了回收率。
文献[10]中反映，当pH低于2时，萃取平衡时间将大大延长，pH=1时，PCP甚至在4h后才能达到平衡，考虑到实际应用，实验中我们测定了同一氯酚混标样在pH=2至pH=6值时的萃取效果（见图4），结果表明，pH值取2时，三种氯酚的萃取效果最佳。 3.5 盐加入量对萃取量的影响 向待测样品中加入一定量的盐类，能产生所谓的“盐析”效应，可以降低氯酚在水中的溶解度，迫使氯酚进入SPME固相涂层中[11]。
实验中，加入饱和的NaCl能明显提高氯酚的萃取量（见表2）。然而，PCP属于例外，因为它的离解常数（pka=4.74）相对较高，中性溶液中其分子状态较少，以离子状态为主[2]，当加入N幻后，由于溶液的离子强度增加，加速了PCP的高解反而使萃取量降低。
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7.化学毕业论文摘要翻译
The actual state, hazards, and prevention and comprehensive treatment of "White Pollution"Abstract: The invention of plastic bag brings people lots of convenience. However, with widespread use and lack of environmental awareness, plastic bags have generated some hazards to the life of human. Along with the development of economy, "White pollution" has been becoming a public nuisance. which negatively affect the sustainable development. China has employed various manners to prevent and treat it to return the green to earth again. Key words:"White pollution", actual state in our country hazard, reasons of formation, prevention manners, comprehensive treatment。
8.英语翻译SPE56535
的SPE 56535 案例研究，扩大水泥，以防止microannular形成baumgarte ，丙，蒂埃瑟兰，米，固相萃取， &克劳斯，四中， Schlumberger dowell 著作权1999年，石油工程师学会公司本文准备，以便在1999年的SPE年度技术会议展览得克萨斯州休斯敦举行， 3-6 1999年10月. 本文之所以选择在陈述一个的SPE程序委员会在审查之后的中所载的资料是一个抽象提交的作者（ ） .文件内容，作为陈述，有没有检讨，由石油工程师学会，并须经校正由作者（ ） .该材料，介绍了，不一定反映任何立场与石油工程师学会，其职员，或成员.论文提交的SPE会议受到出版审查，由编辑委员的社会石油工程师.电子复制，分发，或储存的任何部分本文为商业目的，未经书面同意，在石油工程师学会是禁止之列.许可，复制，印刷的，是仅限于一个抽象的不超过300 换句话说；插图可能不会被复制.抽象必须包含突出确认在何处及由何人该文件.写馆员，固相萃取，口服833836盒，理查森的TX 75083-3836 ，美国，传真01-972-952-9435 .。
9.·化学专业毕业论文摘要翻译
According to according to Lambert - Bill law, when after wave length, liquid sheet thickness determination, the extinction and the colored material's density is proportional. This experiment is with and so on mole of series law carries on the determination, compounds pH4.5~4.8 the series sulfosalicylic acid copper solutions, the sulfosalicylic acid and the cupric ion total material's quantity is invariable, but both's mole fraction changes continuously. Determines this a series of material with the spectrophotometer the extinction. Take a sulfosalicylic acid mole fraction as the abscissa, the extinction is the y-coordinate, makes the extinction constitutional diagram. The solution composition which corresponds with the extinction maximum value is this preparation composition. Through between the ionicity and the extinction, the apparent stability constant's relations carry on the computation, may obtain the sulfosalicylic acid copper apparent stability constant. This experiment is the typical comprehensive nature, the designed experiment, it synthesized the volumetric analysis elementary operation eo skill, the spectral analysis, knowledge and so on chemical literature consult method, and has designed, the zetetic characteristic. It uses in the volumetric analysis and the modern instrumental analysis technology determining the preparation the stability constant, synthesized the volumetric analysis, the spectral analysis, the experiment operation as well as the computer technology unifies. Thus sharpens student's practical ability variously. This experiment's method is simple, fast, and does not need the complex instrument to be possible to determine the preparation the composition and the apparent stability constant. Provides certain reference for the preparation research. Key words: Preparation, composition, apparent stability constant, and so on mole of series law。
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