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71.
Zhang Huijuan Wang Jin Wu Yishi Yuan Gu Ai Xicheng Wang Li Zhang Jianping 《中国科学B辑(英文版)》2006,49(1):75-80
The photophysical properties of the polyamide PyPyPyβDp (PPP) were investigated by means of steady-state absorption and fluorescence
spectroscopies, as well as time-resolved fluorescence spectroscopy. It was found that the excited-state properties of PPP
are very sensitive to solvents. In TKMC buffer PPP exhibited weak fluorescence with a decay time constant of 16 ps, while
with the decrease of the solvent polarity PPP showed the blue-shifted peak position, increased intensity and lengthened life-time
for its fluorescence behavior. In the presence of calf thymus DNA, it was observed that the fluorescence intensity was enhanced
and the fluorescence lifetime increased from 16 to 32 ps for PPP, which verified that PPP bound into the minor groove of DNA
duplex. 相似文献
72.
研究了常压、300~400℃温度范围内在分子筛作用下乙醇和氨的脱水胺化反应,用IR和TPD技术表征其表面酸性。发现分子筛窗口和孔道减小时,二乙胺和三乙胺生成量下降,氢型和碱金属阳离子交换的ZSM-5具有明显的择形作用。乙醇转化率与分子筛表面酸量有关。分子筛上的L酸中心可能是脱水氨化反应的主要活性中心。分子筛上的B酸中心似乎对副反应更有利。 相似文献
73.
The binding constants and thermodynamic properties of a series of novel enediyne compounds with bovine serum albumin (BSA) were determined. The enediynes were synthesized, characterized, and then studied by affinity capillary electrophoresis (ACE) methods to derive these recognition parameters. Change in electrophoretic mobility of BSA as a function of enediyne concentration was determined at 25 degrees C providing binding constants of 1.76 x 10(5), 1.14 x 10(5), and 0.68 x 10(5) M(-1) for enediynephenylalanine carboxylic acid, enediynephenylalanine methyl ester, and enediyne carboxylic acid, respectively. The binding constant for the enediynephenylalanine carboxylic acid was in good agreement with that obtained using conventional methodology. Binding constants for the interaction of enediynes with BSA decreased with an increase in temperature. Van't Hoff plots showed a direct correlation between intensity of the binding constant and the sign and magnitude of various thermodynamic parameters (DeltaG, DeltaS, and/or DeltaH). 相似文献
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Qingqing Wang Yao Zhang Dr. Huijuan Lin Prof. Jixin Zhu 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(62):14026-14035
Considerable attention has been paid to the utilization of CO2, an abundant carbon source in nature. In this regard, porous catalysts have been eagerly explored with excellent performance for photo-/electrocatalytic reduction of CO2 to high valued products. Metal–organic frameworks (MOFs), featuring large surface area, high porosity, tunable composition and unique structural characteristics, have been widely exploited in catalytic CO2 reduction. This Minireview first reports the current progress of MOFs in CO2 reduction. Then, a specific interest is focused on MOFs in photo-/electrocatalytic reduction of CO2 by modifying their metal centers, organic linkers, and pores. Finally, the future directions of study are also highlighted to satisfy the requirement of practical applications. 相似文献
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Huan Liu Chaojun Jiang Yunhua Hui Xiaosheng Shen Xiaoling Zhang Huijuan Yu 《Chromatographia》2010,72(11-12):1083-1088
An analytical method was developed to detect the residue of mebendazole and its metabolites (hydroxymebendazole and aminomebendazole) in the muscle of grass carp and shrimp by LC–UV detection. Mebendazole and its metabolites were extracted with water and ethyl acetate, defatted with hexane, and purified with MCX solid phase extraction column. The intra- and inter-batch precision (measured by CV%) was <9.0%. The accuracy (measured by relative error, %) was <12%. The LODs were 2.5 μg kg?1 for mebendazole and hydroxymebendazole, 5 μg kg?1 for aminomebendazole; the LOQs were 5 μg kg?1 for mebendazole and hydroxymebendazole, 10 μg kg?1 for aminomebendazole. The mean recoveries of mebendazole and its metabolites from grass carp and shrimp muscle at a concentration range of 5.0–500.0 μg kg?1 were 90.7–97.0% with relative standard deviations below 10%. 相似文献
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