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1.
袁承业 《有机化学》2001,21(11):862-868
对氨基膦酸及磷肽的合成作了研究,同时考察了引入二氟次甲基及三氟甲基的方法。在此基础上研究成功基于[1,2]不对称诱导及[1,3]质子转移反应的手性合成方法。对多官能团的氨基膦酸及磷肽也作了研究。此外还制备了具1,1-双膦酸基的多种碳环化合物,对含磷酰基,特别对既含磷酰基又含三氟甲基的多种杂环化合物的合成方法与反应机理进行了报导。  相似文献   

2.
重金属的生物吸附机理及吸附平衡模式研究*   总被引:49,自引:0,他引:49  
各种生物吸附剂包括海洋微生物、发酵工业的菌丝体废渣及活性污泥的提取物等对金属离子的吸附特性已被广泛研究,本文就生物体对金属离子的吸附机理及吸附平衡模式研究进行了综述,阐明了今后的研究方向。  相似文献   

3.
重点综述了芯片上细胞培养和实时检测的微系统研究及相应检测方法和技术近年来的进展.总结了多种光学检测方法和技术体系的优缺点及发展趋势,讨论了各种方法技术对细胞研究模型的研究适用范围,探讨各种检测方法和技术对活细胞、单细胞实时无损无标记检测和传感发展前景和研究进展.最后对整个芯片实验室框架下细胞研究及传感微系统的发展方向进行了有益的思路和方法展望.  相似文献   

4.
用拉伸致孔法制备了 LLDPE/POE/CaCO3防水透湿微孔膜,研究了拉伸倍数及体系组成对微孔膜的微孔结构及防水透湿性能的影响.用 SEM 对微孔膜的微孔结构进行考察,用压汞法对微孔膜的孔径及其分布和微孔的孔隙率进行研究.用静水压法及正杯法分别研究了微孔膜的防水和透湿性能.结果表明:拉伸倍数及 CaCO3用量对微孔膜的孔径、孔隙率及防水透湿性能有明显影响.  相似文献   

5.
丹参素研究概况   总被引:14,自引:0,他引:14  
对丹参素近年来各方面的研究进行了概述,包括丹参素化学结构及性质,提取分离、含量测定及药理研究,为丹参素开发利用提供了依据。  相似文献   

6.
含磷毒剂及其降解产物的气相色谱-质谱测定方法研究   总被引:1,自引:0,他引:1  
研究了用台式气相色谱-质谱仪分析测定含磷毒剂及其降解产物,并对降解产物的衍生化方法及它们的色谱行为进行了研究,总结分析了它们的质谱裂解特点及规律,测定了水样中的含磷毒剂及降解产物。  相似文献   

7.
亲和毛细管电泳研究生物分子的手性识别*   总被引:3,自引:0,他引:3  
结合作者研究组近年来对毛细管电泳的系统研究,评述了亲和毛细管电泳方法研究生物分子的手性识别进展。简要介绍了该领域研究的意义、原理,列举了含有蛋白、抗生素、糖及核酸等4种重要生物分子的作用体系及一些应用,并展望了该领域的发展潜力及前景。  相似文献   

8.
李茂盛  邵令娴  金鑫荣 《色谱》1987,5(6):359-362
国外对酿酒葡萄及葡萄酒的风味作了大量研究,Rapp等研究了10种不同葡萄中的香味组分,发现无论是组成,还是含量都存在显著差异。J.Schimizu等对日本生产的葡萄汁及对应酒中的挥发组分作了大量研究,分析出约100多种组分。国内对葡萄汁和葡萄酒中挥发组分的研究尚未见报道。本文对中国酿酒厂的“北醇”和“苏58”两种葡萄汁和“北醇”红葡萄酒中的挥发性组分进行了研究。  相似文献   

9.
煤中氢键研究的新进展   总被引:4,自引:0,他引:4  
李东涛  李文  李保庆 《化学通报》2001,64(7):411-415
在讨论煤中氢键对煤的结构、性质及转化等方面影响的基础上,总结了研究煤中氢键的常见方法:红外光谱法(IR)及溶胀法等,并将红外研究结果分为3个阶段。总结了调控煤中氢键的方法,并对煤中氢键的研究前景进行了展望。  相似文献   

10.
过氧化酮(Dioxiranes)的研究和应用新进展   总被引:1,自引:0,他引:1  
介绍了近十年过氧化酮的研究及应用情况, 并对其机理研究进行了跟踪.  相似文献   

11.
大口径毛细管气相色谱检查药物中残留溶剂的方法研究   总被引:8,自引:0,他引:8  
姚倩  李章万  张强  叶利民 《色谱》2001,19(2):141-143
 以药物合成中常用的 16种有机溶剂为研究对象 ,建立了用大口径毛细管柱检查残留有机溶剂的气相色谱法 ,并考察了不同极性的色谱柱及不同提取溶剂对分离与检测的影响。实验表明 ,根据原料药合成中可能存在的残留溶剂 ,选用适当的提取溶剂 ,采用大口径毛细管气相色谱法检查 ,可获得较满意的结果。  相似文献   

12.
在涂渍气相色谱固定液时,选用易挥发,低粘度溶剂(如正己烷,丙酮等).担体与溶剂按一定比例混合,溶剂恰好湿润担体,无多余溶剂,涂渍过程不需搅拌、加热等程序,不需旋转蒸发器、水浴、红外灯等设备.此方法具有操作简单,涂渍快速,操作人员中毒少,担体破碎少等优点,而且保证固定液涂渍均匀.本文给出了常用固定液所用易挥发溶剂及常用担体在用本方法涂渍时固定液与溶剂的比例.  相似文献   

13.
Spectroscopic studies of Methyl violet in protic (water, methanol, ethanol, isopropanol and n-butanol) and aprotic solvents (acetone, DMF) were carried out. UV-Visible absorption spectra of Methyl violet in protic solvents showed a hypsochromic shift, as the solvent polarity was changed from less polar to more polar, while a bathochromic shift was observed for aprotic solvents. Transition energy of Methyl violet in different solvents was correlated with solvatochromic parameters to study solute–solvents interactions. The Kamlet–Taft, Catalan and unified scale models were applied to investigate interactions between Methyl violet and solvents. The best agreement is found for the Catalan model.  相似文献   

14.
本工作测定了水杨酸和水杨酸甲酯在不同溶剂中的吸收光谱和荧光光谱,并按在不同温度下测得的结果计算出它们在不同溶剂中平衡过程的函变△H.数据表明,在质子溶剂中,上述化合物有较小的△H值,即形成的分子内氢键只有较低的稳定性.根据这些结果可对该类化合物在不同溶剂中形成内氢键的能力作出恰当的评价.  相似文献   

15.
以20种溶剂作为探针分子,采用反气相色谱技术表征了甲基丙烯酸甲酯-甲基丙烯酸丁酯-甲基丙烯酰氧丙基七环戊基倍半硅氧烷三元共聚物[poly(MMA-co-MBA-co-MA-POSS)]的一系列物理化学性质,并分析了溶剂探针分子与共聚物分子间的相互作用以及共聚物在溶剂中的溶解性.结果表明:在实验温度范围内(343~393K),乙酸甲酯、乙酸乙酯、芳烃、二氯甲烷、三氯甲烷是良溶剂,乙酸丙酯、乙酸丁酯、乙酸戊酯、四氯化碳是中等溶剂,烷烃类和醇类是劣溶剂;随着共聚物中POSS含量的增大,溶剂探针分子溶解聚合物的能力增强,但引入POSS对共聚物的溶度参数无明显影响.  相似文献   

16.
Infrared spectroscopy studies of methyl 4-hydroxybenzoate (MHB) in 17 different organic solvents and in ethanol/CCl4 binary solvent were undertaken to investigate the solvent-solute interactions. The frequencies of carbonyl stretching vibration nu(C=O) of MHB in single solvents were correlated with the solvent acceptor number (AN) and the linear solvation energy relationships (LSER). The assignments of the two bands of nu(C=O) of MHB in alcohols and the single one of that in non-alcoholic solvents were discussed. The shifts of nu(C=O) of MHB in ethanol/CCl4 binary solvents showed that several kinds of solute-solvent hydrogen bonding interactions coexisted in the mixture solvents, with a change in the mole fraction of ethanol in the binary solvents.  相似文献   

17.
高效氯氟氰菊酯; 微乳液; 极性;荧光探针  相似文献   

18.
The solubilities of heat-denatured and reduced, S-carboxymethylated proteins have been investigated in various organic solvents. Polar, protic solvents (formic acid, trifluoroacetic acid, 3-mercaptopropionic acid) were found to be good solvents for the denatured proteins (20-40 mg ml-1), and the solubilities of the reduced, S-carboxymethylated proteins were generally higher than those of the heat-denatured forms. Most other organic solvents were less effective in solubilizing the denatured proteins. Apolar solvents did not solubilise denatured proteins, but low solubilizing powers were observed for polar, aprotic solvents. Heat-denaturation was observed to result in the formation of large intermolecular aggregates, which, for ovalbumin and lysozyme, were formed by intermolecular S-S bonds, but for bovine serum albumin involved intermolecular isopeptide bonds.  相似文献   

19.
氢气在混合溶剂丙酮-水中的溶解度   总被引:6,自引:0,他引:6  
本文报导一种能准确测定气体在混合溶剂中溶解度并能同时测定溶剂的饱和蒸气压的实验装置, 在20~40 ℃的温度范围内, 分别测定了氢气在丙酮、水和混合溶剂丙酮-水中的溶解度, 及其相应的蒸气压。  相似文献   

20.
Nickel oxide films were deposited onto glass substrates by sol–gel dip coating method using solvents of different polarities without any catalysts, templates or surfactants. Methanol, 1,4-butanediol, ethanol, and 2-propanol were used as solvents. The structural, optical and electrical properties of NiO films were investigated using X-ray diffraction (XRD), scanning electron microscopy (SEM), UV–visible spectroscopy and Hall effect measurements, respectively. Nickel oxide thin films with cubic phase crystal structure of various preferred orientations were obtained in the different solvents. The XRD results showed that films deposited from solution using higher polar solvents develop a (1 1 1) preferred orientation, while the (2 0 0)-orientated films were obtained using lower polar solvents. The average particle size increases with viscosity of solvents. Surface morphology of the nickel oxide film consisted of nanoparticles with uniform coverage of the substrate surface. The solvent of higher viscosity induced larger particle size. Band gap narrowing from 4.42 to 3.87 eV was observed using different solvents. The lower resistivity and Hall coefficient was obtained for prepared NiO films using higher polar solvents. The relationships between solvent physicochemical properties, preferred orientation, structural, optical and electrical properties of NiO films were investigated.  相似文献   

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