还原性
- 与 还原性 相关的网络例句 [注:此内容来源于网络,仅供参考]
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It is demonstrated that the chiral quaternary ammonium salts catalysts exhibit promising catalytic properties for the substrate. Part III: The synthesis and the characterizing of the macroporous aminomethyl resin-supported cinchona alkaloid complexes and the study on its catalytic properties The part consists of two subsections. the macroporous aminomethyl resin -supported cinchona alkaloid complexes were synthesized by the stuff (cinchonine, quinine and macroporous aminomethyl resin). Their structures were characterized by means of elemental analysis, XPS, TG/DTA; the chiral polymer-supported complexes were first used as catalysts for the reduction of ketones. Their catalytic properties for the reduction processes were investigated. The comparison of the products e.e., the conversion of the substrate among different reduction processes was employed with determined by HPLC. The effects of the time, the temperature, the ratio of catalyst to substrate, reaction solvent as well as the recycle times were also discussed.
第三章聚-4-氨甲基苯乙烯负载金鸡纳碱金属络合物的合成与表征及其不对称催化性能研究本章分为两节,以辛可宁和奎宁及聚-4-氨甲基苯乙烯为原料,合成了4种聚-4-氨甲基苯乙烯负载金鸡纳碱络合物催化剂,并对它们的结构用元素分析、X-射线光电子能谱、TG/DTA等几种测试手段进行了表征;首次将所合成的手性高分子负载的金属络合物用于催化芳香酮不对称还原反应,详细研究了所得的手性高分子负载的金属络合物对不同底物的催化性能,用HPLC等分析手段定量检测了还原过程的底物转化率及其产物对映异构体选择性,并考察了反应时间、反应温度、催化剂和底物投料比、反应溶剂和循环次数对催化性能的影响。
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In ChapterⅤ, the asymmetric reduction of prochiral ketones using borane as the reagent catalyzed by chiral dysprosium catalyst were described.
第五章主要研究了手性镝试剂催化下硼烷对潜手性酮的不对称还原反应,结果表明异丙氧基镝对硼烷还原酮有明显的催化作用。
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Based on Monte Carlo method,four different weighted function moment methods for Pearson Ⅲ distribution which were developed in China are first compared by using the evaluation standard considering unbiasness and effectiveness of parameters and design values.
利用统计试验方法,以参数及设计值不偏性、有效性为评价标准,比较了现行几种权函数参数估计法,结果与以理想样本还原准则为标准所得的结论截然相反,以不偏性、有效性标准的结论是数值积分权函数法,并未对马秀峰权函数法作出改进,还从理论上比较分析以上两种评价标准,结论是理想样本还原为标准来评判估计方法的优劣存在较大缺陷,建议今后尽量不要使用该标
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The metabolism and succession of microbial population took place ceaselessly during the fermentation and led to microbial polymorphism which mainly presented as anaerobe,methane bacteria,caproic acid bacteria,lactic acid bacteria,sulfate reducing bacteria,and nitrate reducing bacteria etc.
窖泥糟醅是发酵过程微生物栖息的生态环境,其中微生物种群随发酵过程的进行而不停地演替和代谢,具有明显的多态性。其微生物种群的多态性主要表现为厌氧异氧菌、甲烷菌、己酸菌、乳酸菌、硫酸盐还原菌、硝酸盐还原菌等。
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Preparation of the cathode includes:shaping under the press of 40Mpa, sintering at 550℃for 1 hour and at 900℃for 8 hours and threading with molybdenum bar; Considering the literatures we choose CaCl2 as salt for preparation titanium. Pretreatment of salt is for 1 hour at 100℃and for 2 hours at 300℃. Partial pressure of oxygen which need lower than 5.11×10-7Pa to reduct titanium oxides and hygroscopic property of salt need a sealed equipment to electrolyse. And finally successfully designed a satisfied one and the results show that the equipment can be satisfied the requirment of the experiment. Flow of the inert gas is 1.5L/min, the voltage is 2.8 V, temperature is 850℃and time is 2 hours during pre-electrolysis. Flow of the inert gas is 0.2L/min, the voltage is 3.1 V, temperature is 900℃and time changes with the mass of TiO2 during electrolysis, namely the greater need the longer time; To eliminate influence of salt and other impurities, the products need to wash with distilled water and dilute chlorhydric acid , then wash with dilute hydrochloric acid under supersonic wave assistant. Finally, electrometical properties of the electrolysis of TiO2 is researched by cyclic voltammetry and chronoamperometry, and results show that there are two main reodox steps, namely from TiO2 to TiO and from TiO to Ti.
阴极制备主要包括40MPa压力下模压成型、两段式烧结(1小时内升至550℃保温1小时,再1小时升温至900℃保温8小时)及烧结后TiO2块打孔用钼棒串接三个主要环节;实验中选用CaCl2作为电解熔盐,并对其进行预处理(100℃,保温1小时; 300℃,保温2小时);经热力学计算,还原钛氧化物的氧分压至少要低于5.11×10-7Pa,结合电解过程中所用熔盐CaCl2有极强的吸水性的特点,电解装置应有较高的密封性,自行设计了一套密封性可靠的电解装置,便于实验过程中熔盐预处理和氧分压的控制;通过干燥处理预电解过程中Ar流量大约为1.5L/min、电压为2.8 V、温度为850℃、时间为2小时,电解过程中Ar流量大约为0.2L/min、电压为3.1V、温度为900℃,实验结果表明电解时间与TiO2质量密切相关,质量越大需要电解的时间越长;通过自来水冲洗—稀盐酸浸泡、洗涤—在超声波辅助作用下稀盐酸洗涤,可减少熔盐及其它杂质对电解产物检测结果的影响;最后,通过循环伏安法、计时电流法对电解机理的研究,确定电解还原TiO2制备金属钛主要经历了TiO2-TiO-Ti的过程。
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The mechanism of electrocatalytic reduction, the classification and selection of electrode and catalyst and the effect of temperature, current density and pressure on the selective and Faradaic efficiency of reduction are discussed.
介绍了在水溶性介质中利用电化学催化的方法还原CO2的研究现状:电催化还原机理、电极材料催化剂的分类和选择;综述了温度、电流密度以及压力等对还原选择性和法拉第效率的影响;展望了CO2电催化还原方法的研究方向和应用前景。
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The results of asymmetric reduction of latent chiral ketones by carbonyl reductase showed that the enzyme had a high specificity for pentanone in aliphatic ketones and for the acetophenone derivates that contained a withdrawing group at α-position.
利用羰基还原酶不对称催化还原潜手性酮类化合物发现,对于芳香酮类化合物,酶对α位为强电负性基团的底物专一性较强;对于脂肪酮类化合物,酶对五碳脂肪酮的专性较高。
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The results of batch experiments showed that the anaerobic biodegradation kinetics of 2-CNB and 4-CNB by granular sludge were follwed by first-order reaction. The nitro groups of 2-CNB and 4-CNB were more easily attacked by electron than chlorines and they were reductively biotransformed to amino groups under anaerobic conditions. The acclimated anaerobic granular sludge, which could dechlorinate 4-chloroanline to aniline, showed that it had the ability of para-dechlorinating. The anaerobic biodegradating on pathway of 2-CNB and 4-CNB were suggested as follows:AbstractIn ZVI(zero-valent iron, Fe0)-reduction system, the nitro groups of 2-CNB and 4-CNB were reductively transformed to amino groups.
2分批试验结果证明,颗粒污泥降解2-CNB和4-CNB遵循一级动力学,在厌氧条件下,CNB发生序列的硝基还原与脱氯作用,苯环上的硝基比氯原子更容易受到亲电子攻击,发生还原反应生成氨基;所获得的颗粒污泥具有对位脱氯活性,可使4-CA进一步脱氯形成苯胺。2-CNB和4-CNB厌氧降解的建议性途径为: ZVI(Zero-valentiron)对2-CNB和4-CNB的作用主要是将苯环上的硝基还原为氨基;在ZVI与污泥共还原转化体系中,ZVI对氯代硝基苯的硝基转化具有一定的促进作用,但因ZVI对中间产物的吸附特性,终产物形成速率趋慢。
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Sodium lauroyl sarcosine was used as a denaturant, a novel protein refolding method, which was proposed on the basis of one step-AMC and IEC, one step-AMC-IEC was used on the refolding of denatured/reduced lysozyme.
一步人工分子伴侣-离子交换色谱法辅助还原变性溶菌酶的复性:以月桂酰基肌氨酸钠(Sodium Lauroyl Sarcosine,Sarkosyl,SLS)作为蛋白变性剂,发展了一步人工分子伴侣-离子交换色谱法,对还原变性溶菌酶进行了复性研究。
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Part Ⅰ The Research of Chiral Phosphorus Catalysts in the Enantioselective Borane Reduction of Prochiral Ketones ABSTRACT In this paper, the preparation of varied types of chiral phosphorus ligands and their applications as catalysts in the asymmetric borane reduction of prochiral ketones were investigated.
第一部分对映选择的潜手性酮的硼烷还原反应中手性磷催化剂的研究本文研究了多种不同类型的手性磷配体催化剂的合成及其在酮的不对称硼烷还原反应中的应用。
- 推荐网络例句
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However, as the name(read-only memory)implies, CD disks cannot be written onorchanged in any way.
然而,正如其名字所指出的那样,CD盘不能写,也不能用任何方式改变其内容。
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Galvanizes steel pallet is mainly export which suits standard packing of European Union, the North America. galvanizes steel pallet is suitable to heavy rack. Pallet surface can design plate type, corrugated and the gap form, satisfies the different requirements.
镀锌钢托盘多用于出口,替代木托盘,免薰蒸,符合欧盟、北美各国对出口货物包装材料的法令要求;喷涂钢托盘适用于重载上货架之用,托盘表面根据需要制作成平板状、波纹状及间隔形式,满足不同的使用要求。
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A single payment file can be uploaded from an ERP system to effect all pan-China RMB payments and overseas payments in all currencies.
付款指令文件可从您的 ERP 系统上传到我们的电子银行系统来只是国内及对海外各种币种付款。