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71.
荧光光谱法研究盐酸胍浓度不同时变性胰蛋白酶的构象变化 总被引:13,自引:2,他引:11
张静 《光谱学与光谱分析》2004,24(4):455-458
蛋白变性过程中间体的存在是蛋白变性及复性动力学研究中不可缺少的证据。以胰蛋白酶为模型蛋白 ,用荧光光谱法系统地研究了在不同浓度变性剂盐酸胍存在时胰蛋白酶构象的变化 ,并与活性数据进行了对比。发现胰蛋白酶荧光光谱发射波长随变性剂盐酸胍浓度增大而逐渐增大 ,并且当盐酸胍浓度达到 2mol·L- 1 时胰蛋白酶的最大发射波长达到最大值 ,其后随盐酸胍浓度的增大最大发射波长反而逐渐减小 ,当盐酸胍浓度大于 3mol·L- 1 呈现不变的趋势。也就是说 ,在低浓度变性剂环境下 ,胰蛋白酶存在着一个与天然态和完全变性态的分子构象都不同的中间体状态 ,这个中间体状态的荧光发射波长最大 ,荧光发射强度也最大 ,而以此状态为复性起点 ,最终得到的复性产率也最低。对此原因从分子结构的基础上进行了探讨。 相似文献
72.
LIU KaiQiang HE PanLi & FANG Yu Key Laboratory of Applied Surface Colloid Chemistry Ministry of Education School of Chemistry Materials Science Shaanxi Normal University Xi'an China 《中国科学B辑(英文版)》2011,(4)
This article is intended to provide an overview of recent progress in the studies of cholesterol-based low-molecular mass gelators (LMMGs) with unusual properties,in particular,gelation and selective gelation at room temperature,gel emulsions and gel film formation,etc.Potential applications of the LMMGs in spilled oil collection and water purification are briefly presented. 相似文献
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Introduction Dinitroglycoluril (DINGU) is a typical cyclourea nitramine. Its crystal density is 1.94 gcm-3. The detonation velocity corresponding to =1.94 gcm-3 is about 8450 ms-1. Its sensitivity to impact is better than that of cyclotrimethylenetrinitramine. It has the potential for possible use as high explosive from the point of view of the above-mentioned high performance. Its preparation,1-4 properties1-4 and hydrolytic behavior4 have been reported. In the present paper, we report i… 相似文献
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Introduction A series of lanthanide sulfide complexes have beenlargely used for ceramics and thin film materials1 andthese complexes could be prepared from the precursorswhich are the compounds containing lanthanide-sulfurbonds.2-4 For instance, the compounds synthesized with[(alkyl)2dtc]-, phen?H2O and lanthanide salts were usedas the volatile precursors for preparing lanthanide sul-fide, its friction properties in lubricant was investigatedin literature 5 and the preparation and propertie… 相似文献
76.
Introduction During the past several decades, diamines and their derivatives have been extensively investigated in both basic research and their application. The result shows that they can form stable complexes with many transi-tion metals. These complexes would be widely applied in various fields such as biotechnology,1 synthesis,2 food processing industry,3 environmental science,4 biochemistry,5 etc. Especially, in recent years, more and more attention is placed on their other peculiarities.… 相似文献
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Kinetic Study on the Exothermic Decomposition Reaction of 2,4,6,8-Tetranitro-2,4,6,8-tetraazabicyclo[3,3,1]onan-3,7-dione 总被引:1,自引:0,他引:1
Introduction 2,4,6,8-Tetranitro-2,4,6,8-tetraazabicyclo[3,3,1]nonan- 3,7-dione (1) is a novel energetic cyclourea nitramine containing four —NO2 groups (Figure 1). The detona-tion velocity corresponding to =1.93 gcm-3 is 9034 ms-1. It is the potential high explosive. Its preparation,1 properties1 and hydrolytic behavior2 have been reported. Thermal behavior is one of the most important aspects of the compound in practical application. However, its kinetic parameters of thermal decomposition… 相似文献
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A novel water soluble ditopic guest,the quaternary ammonium salt of N,N′-bis(ferrocenylmethylene)-diami-nobutane (1),and a known water soluble ditopic host,benzenetetracarboxylic dianhydride bridged bis(β-cyclo-dextrin)s (2),have been synthesized and characterized.~1H NMR spectra and cyclic voltammogram (CV) studies re-vealed the host-guest interactions between them in aqueous solution.The supramolecular interaction also exists insolid state as confirmed by the studies of the solid samples,which were obtained by frozen-drying the solution sam-ples,using FTIR spectroscopy and differential scanning calorimetry (DSC) techniques.TEM measurement demon-strated that wire-shaped supramolecular aggregates exist in the aqueous solution of the two compounds.The lengthsof the aggregates could reach micrometers. 相似文献
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The common explosives, RDX (1,3,5-trinitro-1,3,5-triazacyclohexane), HMX (1,3,5,7- tetranitro-1,3,5,7-tetraazacyclooctane) and TNT (trinitrotoluene), were considered adequately for all weapons applications. Due to many catastrophic explosions resulting from unintentional initia-tion of impact, friction or shock, these explosives have become less attractive. TATB (1,3,5-tria- mino-2,4,6-trinitrobenzene) is noted for its insensitivity, however, it does not have the energetic performance of e… 相似文献
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本文研究了Hilbert空间中的有效序列,通过引入序列的伴随序列,给出了有效序列的一个等价刻画,接着讨论了保持向量序列有效性的线性算子的性质,证明了一个线性算子将任意有效序列映射为有效序列当且仅当它是酉算子;最后,给出了正规正交基中添加一个单位向量后所得到的序列是有效序列的一个充要条件. 相似文献