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1.
葡辛胺的催化加氢合成工艺的研究   总被引:3,自引:0,他引:3  
系统地研究了以Raney镍为催化剂同呼正辛胺形成Schiff碱后催化加氢合成葡辛胺的反应,通过对反应条件的优化,特别是通过向反应体系中加入催化剂量的三乙胺,改善了催化剂的性能,降低了催化剂的用量,有效地抑制了副反应的发生,缩短了反应时间,反应产率达到70%以上,并对失活的Raney镍催化剂的再生进行了初步试探。  相似文献   

2.
聚碳酸酯聚氨酯弹性体的模拟生物老化性能的研究   总被引:1,自引:0,他引:1  
研究了聚碳酸酯聚氨酯的水解剂,氧化,钙化等生物老化性能,并与聚醚聚氨酯样品做了比较,结果表明,胺扩链样品具有较好的耐水解性能,聚碳酸酯氨酯的抗氧化性能优于聚醚聚氨酯,同了聚醚氨酯一样,聚碳酸酯聚氨酯同样受钙的影响,含水氯化钙对聚碳酸酯聚氨酯的相结构产生影响,并对弹性具有增强作用。  相似文献   

3.
稀土抛光粉的生产及应用   总被引:22,自引:0,他引:22  
综述了稀土抛光粉的各种制造工艺及其在玻璃抛光领域的应用现状,以稀土抛光粉不同的化学成分,粒度,用途等对稀土抛光粉进行了归纳分类,介绍了国内外稀土抛光粉生产企业的产生规律,产品特点,对国内外稀土抛光粉的制备工艺流程进行了归纳,阐述了稀土抛光粉的抛光工艺及抛光机理,重点讨论了稀土抛光粉的应用领域,预测了稀土抛光粉市场的未来,对稀土抛光粉的应用进行了展望。  相似文献   

4.
超临界萃取中药白芷的化学成分的气相色谱质谱分析   总被引:12,自引:2,他引:12  
采用超临界流体萃取法对传统中药白芷的化学成分进行了分离提取研究,利用气相-质谱联机技术,对其中的55种化学成分进行了鉴定,并测定了相对含量。与传统的水蒸气蒸馏法提取的白芷挥发油进行了比较,分析。实验结果表明,超临界CO2萃取法所得的产物,能保留药材白芷的所有有效成分,可以入药。  相似文献   

5.
用量子化学方法研究了双硅烷1,2-氢迁移热分解,全参量优化了反应物及产物的平衡几何构型,找到了反应途径,获得了过渡态,并对过渡态进行了振动分析,活化能的计算值与实验值一致,从理论上证明双硅烷通过1,2-氢迁移的热分解途径的可行性。  相似文献   

6.
申文杰  胡津仙 《合成化学》1997,5(4):331-337
介绍了甲醇,异丁烯合成甲基叔丁基醚的催化剂,热力学,动力学。综述了合成MTBE的主原原料异丁烯的生产过程,并总结了甲醇,异丁醇和甲醇,叔丁醇合成了MTBE的研究开发进展,参考文献16篇。  相似文献   

7.
液膜稳定性的研究   总被引:4,自引:1,他引:4  
利用单滴法对三种表面活性剂的液膜体系的稳定性进行了研究,重点考察了载体的影响,讨论了介质与表面活性剂,介质与载体,载体与表面活性剂的相互作用对液膜稳定性的影响,并根据膜强度数据,给出了液膜稳定的条件。  相似文献   

8.
若干含多硫基的配合物的合成方法及结构特征   总被引:1,自引:0,他引:1  
本文综述了近年来我们合成的十二种多硫基的配合物,这些配合物含有S^2-2,S^2-4,S^2-5,S^2-6,S^2-7等多硫革配体,总结了这些配合物中的金属配位构型,比较了各种多硫基的S-S键长及有关键角,归纳了配合物外光谱,并阐述了其中几个配合物与NH2NH2的反应性能。  相似文献   

9.
利用单滴法对三种表面活性剂的液膜体系的稳定性进行了研究,重点考察了载体的影响,讨论了介质与表面活性剂,介质与载体,载体与表面活性剂的相互作用对液膜稳定性的影响,并根据膜强度数据,给出了液膜稳定的条件。  相似文献   

10.
叙述了CAHN-2000磁天平(美国)调试过程中如何解决液氮温区的测试,自制了磁天平与计算机的接口,编写了数据采集、处理和控制等高原 软件,节省了几万美元,部分指标超过原配套水平,三年来仪器在对国同外开放过程中,液氮温区的工作一直正常,实测了上千个样品,提供的数据已撰写数十篇文章在国内外刊物上发表。由此说明,要充分发挥进口仪器的使用效率,必须对仪器的工作原理、结构特点有透乇的了解,同时要有相当的自  相似文献   

11.
利用手持技术改进测定乙醇分子结构实验   总被引:1,自引:0,他引:1  
利用压强传感器代替排水集气法,改进测定乙醇分子结构实验的仪器装置,并探索最佳反应条件。另外,设计两个空白实验,结合压强变化曲线对实验误差进行相关讨论。  相似文献   

12.
13.
由于石化行业的生产需要,其材质的使用具有多样性和广泛性,经常会出现顾客委托的测试样品的一个或几个元素跨越光谱仪现有测试程序测量范围的情况。本法通过对光谱仪测试原理的认识,根据光谱仪的测试能力及标样的采集,实现了一个或几个元素测量范围的扩展,并对其测量的影响因素进行了研究。  相似文献   

14.
The oxygen quenching rate constants for singlet and triplet excited states of the dimethyl ester of mesoporphyrin IX increase with decreasing viscosity of the medium and reach a maximum at a viscosity of approximately 0.4 mPa·sec, after which the rate constants begin to decrease. The drop in rate constant with increasing fluidity of the medium may be related to a nonequilibrium character of the elementary act in the interaction of the reactants in the solvent cage. In viscous media such as isopropyl alcohol, isobutyl alcohol, and isoamyl alcohol, the reaction radius is greater than the sum of the radii of the reacting particles. The long-range character of these processes is due to the relatively weak dependence of the quenching probability on distance.Translated from Teoreticheskaya i Éksperimental'naya Khimiya, Vol. 25, No. 2, pp. 161–167, March–April, 1989.  相似文献   

15.
The spectral-polarization characteristics of absorption and phosphorescence of molecules of the initial form of nitro-substituted indolinospirobenzothiopyran were studied in oriented polyethylene films and in solutions with different polarity. An oscillator model of the electron transitions responsible for the formation of absorption and luminescence spectra was suggested. It was established that the principal differences in the spectral and photophysical properties of the compound studied and its oxygen-containing analog are associated with the fact that the electronegativity of the S atom is lower than that of the O atom. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 6, pp. 1143–1146, June, 1997.  相似文献   

16.
The compositions of the neutral diterpenoids of the oleoresins of five species of conifers growing in the Transcarpathia have been studied. It has been found that the oleoresins ofAbies alba M.,Larix decidua M., andPicea excelsa L. contain more than 50% of neutral diterpenoids. The group and qualitative compositions of the oxygen-containing diterpenoids have been determined. In the oleoresins ofAbies alba,Picea excelsa, andPicea abies tertiary alcohols — cis-abienol and isocembrol — predominate, while inLarix decidua the main component is the hydroxy ester larixyl acetate. Primary alcohols related to the resin acids have been found in all the oleoresins investigated. Features of the distribution of diterpenoids according to the species of conifers have been revealed. The results obtained are necessary for the chemotaxonomy of conifers of the family Pinceae.Novosibirsk Institute of Organic Chemistry, Siberian Branch, Academy of Sciences of the USSR. Translated from Khimiya Prirodynkh Soedinenii, No. 6, pp. 812–816, November–December, 1988.  相似文献   

17.

The heats of detonation of 20 simple high explosives and explosive mixtures were determined by means of an adiabatic detonation calorimeter designed by the authors. The results indicated that the performance of the instrument was reliable and the experimental data were very accurate. For explosive mixtures, there was a linear accumulative relationship between the heats of detonation of the explosive mixture and its components. Accordingly, the heats of detonation of explosive mixtures could be calculated directly from the heats of detonation of simple explosives and the characteristic heats of other components. The experiments showed that the gold or brass shell of the cylindrical charge could be substituted by a thick-walled porcelain shell, which had the advantage of cheapness.

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18.
实验教学目的是从解决实际问题出发,以实验技术训练和实验设计思想培养为目标。介绍了将单一的物质分配系数测定实验改进为综合实验,提高了实验效果及实验资源利用率。  相似文献   

19.
Sets of hydrogen molecule equivalents have been developed which permit the calculation of hydrogenation of different types of carbon-carbon bonds from ab initio total energies (3-21G and 6-31G* basis sets, and, to a more limited extent, for MP2/6-31G* data) of reactants and products. The calculated enthalpies of hydrogenation are in good agreement with experiment for unstrained molecules, with average errors on the order of 2 kcal/mol. The 6-31G* equivalents allow the enthalpies for strained molecules to be calculated accurately, but the 3-21G equivalents do not. The equivalents for both basis sets have been tested by calculating the enthalpies of hydrogenation of carbon-carbon bonds in nitrogen- and oxygen-containing organic molecules, free radicals, and classical carbocations. The results are in good agreement with experiment in most cases.  相似文献   

20.
非那雄胺能抑制5α-还原酶的活性,明显降低二氢睾酮水平,是一种治疗良性前列腺增生的有效药品。该合成工艺以甾烯酮酸为原料,将其与氯化亚砜反应,无须分离即与叔丁胺反应得17β-酰胺化合物,再氧化开环,环合,氢化,脱氢合成了非那雄胺。经元素分析、IR、1HNMR、13CNMR、MS分析表征了其结构。该法无须使用昂贵的2,2-二吡啶二硫化物和剧毒药品苯亚硒酸酐,且以乙酸铵代替氨气,降低了对设备的要求和腐蚀,更适用于工业生产。  相似文献   

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