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1.
Journal of Sol-Gel Science and Technology - Multifunctional magnetic mesoporous nanocomposites are promising materials to remove the various pollutants from water due to the remarkable properties...  相似文献   
2.
吖啶类衍生物的荧光性质   总被引:4,自引:0,他引:4       下载免费PDF全文
用比较法测得23种啶类衍生物的荧光量子效率(Φf),以评估这些化合物的荧光性质,结果表明,N-烃基吖啶酮类化合物的荧光量子效率要比9-取代苯基吖啶类和9-取代苯亚甲基-10-甲基-9,10-二氢吖啶类化合物的荧光量子效率大,在非极性溶剂中,9-聚代苯亚甲基-9,10二氢吖啶分子内的强吸电子基NO2增强荧光量子效率,强推电子基OCH3降低荧光量子效率,这些测量结果与取代基的电子作用经验规律不相符,这种现象可以用分子内电荷转移理论进行解释。  相似文献   
3.
以1,3-二硫杂环戊烯-2-硒酮-4,5-二硫盐为配体与二价金属离子配位合成了4种双(1,3-二硫杂环戊烯-2-硒酮-4,5-二硫)金属配合物,研究了它们的电化学性质和UV—Vis光谱,并讨论了形成中性产物的原因。  相似文献   
4.
A cyclotriphosphazene substituted with six 3,5-bis(trifluoromethyl) benzyloxy units was designed as a novel 19F MRI contrast agent. The resulting molecule has 36 magnetically equivalent fluorine atoms and exhibited suitable MRI properties with high imaging sensitivity, confirming the proof-of-concept as a convenient scaffold for the production of new 19F MRI contrasts agents.  相似文献   
5.
In this paper, first, we prove the weighted Hermite–Hadamard–Mercer inequalities for convex functions, after we establish some new weighted inequalities connected with the right‐sides of weighted Hermite–Hadamard–Mercer type inequalities for differentiable functions whose derivatives in absolute value at certain powers are convex. The results presented here would provide extensions of those given in earlier works.  相似文献   
6.
Making use of the regular solution theory with binary coefficients, the partition of benzole acid between aqueous benzene phases was investigated. ΔH, ΔS and ΔG thermodynamic functions associated with the hydration-corrected partition and dimerization were calculated. It was found that the partition was spontaneous at high temperatures and of the hydrates of benzoic acid, the monohydrate monomer was dominant at high temperatures.  相似文献   
7.
    
Ohne Zusammenfassung  相似文献   
8.
With the rapid development in computer technologies, mathematical programming-based technique to solve scheduling problems is significantly receiving attention from researchers. Although, it is not efficient solution method due to the NP-hard structure of these problems, mathematical programming formulation is the first step to develop an effective heuristic. Numerous comparative studies for variety scheduling problems have appeared over the years. But in our search in literature there is not an entirely review for mathematical formulations of flexible job shop scheduling problems (FJSP). In this paper, four the most widely used formulations of the FJSP are compiled from literature and a time-indexed model for FJSP is proposed. These formulations are evaluated under three categories that are distinguished by the type of binary variable that they rely on for using of sequencing operations on machines. All five formulations compared and results are presented.  相似文献   
9.
以布洛芬乙酯为反应底物,探索了酶促水解法拆分布洛芬的工艺。以曲拉通X-100为表面活性剂,利用南极假丝酵母脂肪酶B(CAL-B)催化拆分外消旋布洛芬乙酯,并对表面活性剂含量、有机溶剂种类和添加量、酶量、缓冲溶液pH、温度及时间等反应条件进行了优化;得到的最佳反应条件为:在pH为9.0的缓冲溶液中,添加80 mg曲拉通X-100、50 μL二氯甲烷和15 mg CAL-B,于30℃下反应48 h;在该条件下,S-布洛芬乙酯的剩余率(C)为65%,布洛芬乙酯的对映体过量值(ees)为94%。  相似文献   
10.
李灿 《化学通报》2016,79(7):671-671
正河北大学药学院朱华结教授编著的《Organic Stereochemistry—Experimental and Computational Methods》(有机立体化学—实验与计算方法)[1],由世界著名出版社Wiley-VCH正式面向全球出版发行。应作者邀请我很高兴向大家推荐这本著作。手性是自然界普遍而重要的特征。自然界中很多分子虽然原子组成相同,但其空间结构完全不同,呈实物与镜像不重合的关系,因而被形象地  相似文献   
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