化
- 与 化 相关的网络例句 [注:此内容来源于网络,仅供参考]
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To be different from the already chloromethylation catalyst, it has a certain amount of moisture wet, which will not produce huge amounts of doughtic cancerogenic chloromethyl methyl ether during and after the reaction.4,4\'-bisbiphenyl, 1,4-bisbenzene, 1,4-bis(chloro- methyl)-2,5-dimethylbenzene, 1,5-bis-2,4-dimethylbenzene, 4-(chlor- omethyl)-1,2-dimethylbenzene, 1,2-bis-4,5-dimethylbenzene, 5,8-bis-1,2,3,4-tetrahydronaphthalene, 3,3\',5-tris-4,4\'-bisbiphenyl and 3,3\', 5,5\'-tetrakis-4,4\'-bisbiphenyl were synth- esized by using this new catalyst. Results indicated that when the reaction temperature was 55~60℃, the reaction time was 12h, the catalyst which consists of the concentration of 80%H_2SO_4, HAc and Lewis acid, the amount of Lewis acid 0.15 mol(nLewis:nbiphenyl=1.5:1), yield of biphenyl chloromethylation product 4,4\'-bis(chrolomethylbiphenyl can reach a maximum 85%.
采用这种催化体系完成了4,4′-二氯甲基联苯、对二氯甲基苯、1,4-二氯甲基-2,5-二甲基苯、1,5-二氯甲基-2,4-二甲基苯、4-氯甲基-1,2-二甲基苯、1,2-二氯甲基-4,5-二甲基苯、5,8-二氯甲基-四氢萘、3,3',5-三氯甲基-4,4'-二甲基苯和3,3',5,5'-四氯甲基-4,4'-二甲基苯的合成,结果表明:在反应条件为:反应温度55~60℃,反应时间12h,选择80%H_2SO_4、冰醋酸和Lewis酸为催化剂,反应最佳反应Lewis酸用量是0.15mol(和原料比为1.5:1),反应效果最好,联苯氯甲基化产物(4,4′-二氯甲基联苯)收率为85%;在反应条件为:反应温度70℃,反应时间8h,80%H_2SO_4、冰醋酸和Lewis酸为催化剂,反应最佳反应Lewis酸用量是0.1mol(和原料比为1:1)时,反应效果最好,苯的氯甲基化产物收(来源:ABd0C论文eded网www.abclunwen.com)率为75%;在反应条件为:在反应条件为:反应温度40℃,反应时间10h,60%H_2SO_4和Lewis酸为催化剂,反应最佳反应Lewis酸用量是0.1mol(和原料比为1:1)时,反应效果最好,对二甲苯氯甲基化产物(1,4-二氯甲基-2,5-二甲基苯)收率为78.5%;在反应条件为:反应温度35℃,反应时间10h,60%H_2SO_4、冰醋酸和Lewis酸为催化剂,反应最佳反应Lewis酸用量是0.1mol(和原料比为1:1)时,反应效果最好,间二甲苯氯甲基化产物(1,5-二氯甲基-2,4-二甲基苯)收率为81.5%。
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From the results, the extraction was optimized by using microwave-assisted derivatization at 300 watt for 3 sec with methyl chloroformate/methanol derivatization reagent and sample solution in the ratio of 2:1, and then extraction 30 min.
实验结果显示,利用搅拌子吸附萃取法结合气相层析质谱术分析尿液中胺基酸,衍生化功率为300瓦,衍生化时间为3秒,水样与氯甲酸甲酯/甲醇衍生化试剂体积比为2:1时有最佳衍生化条件。
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Methods①The animal model of braincontusion caused by free drop hammer was established.②The injuredtissue of rat brain were stained by TUNEL for apoptosis,immunohistochemistry for Caspase-3 and Feulgen"s for DNA. Image analysistechnique and the statistical method were employed to explorate thetemporal changes of injury time.③The DNA was extracted from ratcontusive tissue of brain and assayed by gel electrophoresis toinvestigate the relationship between the DNA fragmentation and injurytime.④One handred and seventeen cases of death from traumatic braininjury were retrospective researched to investigate the characteristicof TBI in forensic medicine.⑤The contusive tissue of human brain werestained by TUNEL, Caspase-3 immunohistochemistry and Feulgen"s methodsin the same way to analyze and disclose the linear relationship betweentemporal changes with injury time.
方法①建立大鼠自由落体打击脑损伤模型;②对不同损伤时间组的大鼠脑挫伤组织进行TUNEL、Caspase-3免疫组化、Feulgen's DNA染色,结合图像分析技术和统计学分析,探讨脑挫伤后神经细胞凋亡、DNA片段化和含量的时序性变化;③提取大鼠脑挫伤组织DNA进行琼脂糖凝胶电泳分析,观察DNA片段化随损伤时间的变化特点;④对117例颅脑损伤致死案例进行回顾性分析,探讨其法医学特点;⑤选择不同损伤时间的人脑挫伤组织同样进行TUNEL、Caspase-3免疫组化、Feulgen's DNA染色和分析,观察上述指标与损伤时间的关系。
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The Socio-historical Background to Pidginization and Creolization.
洋泾滨化和克理奥尔化的社会历史背景>刊于《语言的洋泾滨化和克理奥尔化》Dell Hymes主编。
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The effect of annealing temperature and different substrates on film crystallographic quality and surface morphology was investigated.
对sol-gel法制备的PbTiO3薄膜采用不同晶化工艺进行晶化,研究了晶化温度和基片对薄膜晶化的影响。
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Using ethyl cyanoacetate , triethyl orthoformate and methylhydrazine as main raw materials, the herbicide pyrazosulfuron was prepared through the reactions of substitution, amination, cylclization, diazotization and chlorosulfonation.
以氰乙酸乙酯、原甲酸三乙酯和甲肼等为主要原料,通过取代、胺化、环化、重氮化和氯磺化等反应制得了除草剂吡嘧磺隆原料药。
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The analysis of thermal behavior and chemical structure show that the three main reactions do not initiate simultaneously. Dehydrogenization and cyclization reactions begin at the initial stage of stabilization, while oxidation reaction takes place on the precondition of cyclization reaction. Cyclization reaction has induction period that is influenced by temperature and heating rate.
热分析和化学结构分析的结果表明,预氧化过程中的三大主要反应并非同时进行,脱氢反应和环化反应从预氧化初期开始,而氧化反应需要以环化反应为前提条件,随后进行;环化反应具有一定的诱导期;在氧化性气氛中,首先发生脱氢反应,氧对环化反应起到了阻碍作用,使整个过程顺利可控。
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With cellulose as the skeleton, gelatinized cassava starch solution and tungsten carbide were used as porogenic agent and inert densifier, respectively. The matrix prepared showed good sphericity and a logarithmic symmetrical distribution of particle size.
取得的主要结果如下:纤维素基复合层析基质的物理功能化:以再生纤维素为骨架,碳化钨粉末为增重剂,糊化木薯淀粉为制孔剂,采用&反相悬浮热再生法&和成球后去除淀粉方法,成功制备了纤维素/碳化钨复合微球,可用作层析介质的基质。
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This work, concentrated on the asymmetric allylation of aldehydes controlled by different chiral auxiliaries prepared from rotational pure tartaric acid, can be divided into three parts.The first part aims to review the developments of chiral drugs and asymmetric synthesis, from which derived the present research topic backgrounds and works.Synthesis and applications of allylation from aldehydes are the second part of the thesis. By optimizing the reaction conditions, such as solvents, temperature, time and chiral auxiliaries like N,N\'-dibenzyl tartamide, N,N\'-p-dimethylphenyl tartamide, N,N\'-o-dimethylphenyl tartamide, N,N\'-o-dichlorophenyl tartamide, N,N\'-a-dinaphyl tartamide, N,N\'-dicyclohexyl tartamide and N,N\'-diphenyl tartamide, ideal experimenttal conditions are obtained according to HPLC monitoring, as well as the auxiliaries\' recoveries experiments. Starting from benzaldehyde and 3-bromopropaldehyde, N,N\'-dibenzyl tartamide is considered the best auxiliary in this reaction.
本文介绍了醛的不对称烯丙基化反应,以光学纯酒石酸为原料,研究了不同构型手性配体在醛的烯丙基化反应中的立体选择性,全文共分三部分十个章节:第一部分对当前手性药物和手性技术进行了概述,并由此展开了本文的研究背景和任务;第二部分为有机合成部分,对醛的不对称烯丙基化反应进行了深入探讨,以苯甲醛为原料对反应条件进行优化,在优化的反应条件下对制备的七种可回收手性酰胺配体(N-苄基酒石酸二酰胺、N-对甲苯基酒石酸二酰胺、N-邻甲苯基酒石酸二酰胺、N-邻氯苯基酒石酸二酰胺、N-a-萘基酒石酸二酰胺、N-环己基酒石酸二酰胺和N-苯基酒石酸二酰胺)进行筛选,优化配体回收实验条件,最终确定出N-苄基酒石酸二酰胺在苯甲醛的不对称烯丙基化反应中具有较大优越性,结晶回收的手性配体光学纯度保持不变。
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Although the ion-exchange capacity of membrane quaternized by methyl iodide is higher than that of membrane quaternized by methylene diiodide,mechanical properties of the former are too poor to form membranes.
以一碘甲烷为季铵化试剂制备的离子交换膜其离子交换当量要比以二碘甲烷为季铵化试剂的要高,但机械强度差。在相同条件下,提高反应温度,有利于膜的季铵化反应,而不利于膜的磺化反应。
- 推荐网络例句
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According to the clear water experiment, aeration performance of the new equipment is good with high total oxygen transfer coefficient and oxygen utilization ratio.
曝气设备的动力效率在叶轮转速为120rpm~150rpm时取得最大值,此时氧利用率和充氧能力也具有较高值。
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The environmental stability of that world - including its crushing pressures and icy darkness - means that some of its most famous inhabitants have survived for eons as evolutionary throwbacks, their bodies undergoing little change.
稳定的海底环境─包括能把人压扁的压力和冰冷的黑暗─意谓海底某些最知名的栖居生物已以演化返祖的样态活了万世,形体几无变化。
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When I was in school, the rabbi explained everythingin the Bible two different ways.
当我上学的时候,老师解释《圣经》用两种不同的方法。