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961.
962.
Starting from the hydroxylamine (dimethyl amino ethanol, triethanolamine) and 1,3-propane sultone, a series of hydroxyl and sulfonyl dual-functionalized zwitterionic salts and corresponding acidic room temperature ionic liquids have been synthesized. The hydroxyl groups of the synthesized substances were confirmed by the 1H NMR measurement. These zwitterionic salts and ionic liquids may be used for synthesizing other functionalized ionic liquids or ionic liquid-polymer (polyelectrolyte).  相似文献   
963.
A new fluorescent compound based on calix[4] arene skeleton was synthesized.Its complexation ability with transition metal ions,such as Fe^3 ,Co^2 ,Ni^2 ,Cu^2 ,Zn^2 and Ag^ ,Was investigated by UV-vis and fluorescent spectra.  相似文献   
964.
Directly making light olefins via CO hydrogenation is a promising process to obtain a nonpetroleum based supply of alkenes.Limited by the ASF distribution function of Fischer-Tropsch synthesis,the yield of light olefins (C2-C4) can not reach the desired levels,which is a great challenge to overcome.Beginning thermodynamic analysis,the ASF distribution function,the reaction performance of CO hydrogenation and slurry reactor studies.The problems currently faced by this research area are presented at the end of the article.  相似文献   
965.
Comprehensive two-dimensional liquid chromatographic separation by means of a combination of ion-exchange chromatography (IEC) and reversed-phase liquid chromatography (RPLC) has been realized and applied to the analysis of components of a traditional Chinese medicine Flos Lonicera. In the first dimension the components of a Flos Lonicera extract is separated on strong anion-exchange (SAX) column according to the charge-exchange properties of the components. In the second dimension the components are further fractionated by reversed-phase liquid chromatography (on ODS) on the basis of their hydrophobicity. The RPLC effluent is desalted and split and the components are identified on-line by use of both diode-array detection and mass spectrometry with atmospheric pressure chemical ionization (APCI–MS). In this way, the extract of Flos Lonicera can be rapidly separated, desalted, and analyzed, with determination of molecular weight. More than 58 components of an extract of Flos Lonicera were well resolved and six were tentatively identified from their UV and mass spectra.  相似文献   
966.
(3R*,3aR*,9aR*)-3,9a-Dimethyl-2,3,3a,9a-tetrahydro-4H-furo[2,3-b]chromene-5,7-diol (xyloketal H), a representative of a new family of xyloketals, was isolated from the marine-derived mangrove fungus Xylaria sp. 2508. Its structure was elucidated by spectroscopic data and single-crystal X-ray diffraction analysis. Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 6, pp. 1051–1052, June, 2006.  相似文献   
967.
李华  杨翌秋 《分析化学》1995,23(1):25-28
本文讨论了29个不对称色酸双偶氮膦酸型显色剂的分子联接性指数,并将其与结构选择性因子相结合,用于偶氮类剂结构与铈显色反应灵敏度的相关性研究,讨论了显色剂结构对显色反应灵敏度的影响。  相似文献   
968.
由混合二烃基二氯化锡(RR'SnCl_2)与水杨醛缩苯胺类Schiff碱(2-HOC_6H_4CH=NAr)反应,合成了14种新的有机锡配合物。经元素分析、IR、NMR和TG-DSC测定,确定配合物的组成是有机锡与Schiff碱的1:1配合物,配体以酚羟基氧原子与锡原子配位,摩尔电导率测定表明配合物均为非电解质。  相似文献   
969.
杨勇  李骏 《电化学》1996,2(4):363-371
贮氢合金材料电化学与表面性能的研究进展①杨勇李骏林祖赓(厦门大学化学系,固体表面物理化学国家重点实验室,厦门361005)八十年代后期以来,人们对地球的环境保护提出了更高的要求,而便携式电器(如移动电话,摄像机与笔记本电脑等)对电池的需求也大量增加...  相似文献   
970.
Under certain collision conditions, a swift ion projectile colliding with a target will gain rather than lose kinetic energy, contrary to the standard conception of stopping power. In this work, we consider the conditions for such a collision such that the energy loss is negative, that is, that there will be projectile kinetic energy gain. In particular, for a target initially in the ground state we find that the projectile gains kinetic energy only when charge exchange and de‐excitation processes are involved. This occurs when the electron affinity of the projectile is larger than the ionization potential of the target. Consequences of this effect are analyzed. © 2003 Wiley Periodicals, Inc. Int J Quantum Chem 94: 215–221, 2003  相似文献   
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