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991.
Bound state solutions of D‐dimensional schrödinger equation with exponential‐type potentials 下载免费PDF全文
José Juan Peña Jesús García‐Martínez Jesus García‐Ravelo Jesus Morales 《International journal of quantum chemistry》2015,115(3):158-164
In this article, using an exactly‐solvable multiparameter exponential‐type potential we propose a unified treatment of the analytical bound—state solutions of the Schrödinger equation for exponential‐type potentials in D‐dimensions. Our proposal accepts different approximations to the centrifugal term; however, its usefulness is exemplified in the frame of the Green and Aldrich approach. This fact enables us to compare our results with specific potentials found in the literature and that are obtained here as particular cases of our proposal. That is, instead of solving a specific exponential‐type potential, by resorting each time to a specialized method, the energy spectra and wavefunctions are derived straightforward from the proposed approach. Furthermore, our proposal can be used as an alternative way in the search of solutions to new exponential‐type potentials besides that one can study different approximations to the term . © 2014 Wiley Periodicals, Inc. 相似文献
992.
Structure and Absolute Configuration of Aspergilumamide A,a Novel Lumazine Peptide from the Mangrove‐Derived Fungus Aspergillus sp. 下载免费PDF全文
Cai‐Juan Zheng Lu‐Yong Wu Xiao‐Bao Li Xin‐Ming Song Zhi‐Gang Niu Xiao‐Ping Song Guang‐Ying Chen Chang‐Yun Wang 《Helvetica chimica acta》2015,98(3):368-373
A novel lumazine peptide, aspergilumamide A ( 1 ), as well as a known analog penilumamide ( 2 ), were isolated from the mycelia of a marine‐derived fungus Aspergillus sp. (33241), obtained from the mangrove Bruguiera sexangula var. rhynchopetala collected from the South China Sea. The structure of 1 was identified by comprehensive spectroscopic analysis, including 1D‐ and 2D‐NMR, ESI‐MS, and MS/MS experiments. The absolute configuration of 1 was determined by Marfey's method. 相似文献
993.
Stimulated by the recent experimental success in production and characterization of YCN@Cs(6)‐C82, the possibility of encapsulating YCN cluster in the C78 fullerene has been performed using density functional theory. Six isomers of YCN@C78 are considered based on six lowest energy C782? isomers. The results reveal that YCN@D3h(24109)‐C78 and YCN@C2v(24107)‐C78, both of which satisfy the isolated‐pentagon rule, present excellent thermodynamic stability with very small energy differences. Moreover, the large HOMO‐LUMO gaps (1.55 and 1.47 eV for YCN@D3h(24109)‐C78 and YCN@C2v(24107)‐C78, respectively) indicate their high kinetic stabilities. Significantly, in both the structures, the encapsulated YCN cluster is triangular, similar to the cases of YCN@Cs(6)‐C82 and TbCN@C2(5)‐C82. In addition, electronic absorption spectra, infrared spectra, and 13C nuclear magnetic resonance spectra of two stable structures have also been explored to further disclose the molecular structures and properties. © 2015 Wiley Periodicals, Inc. 相似文献
994.
995.
Xuting Wang Dr. Yanxia Zhao Shida Gong Prof. Bin Liu Prof. Qian‐Shu Li Prof. Ji‐Hu Su Prof. Biao Wu Prof. Xiao‐Juan Yang 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(38):13302-13310
Reactions of the dimeric cobalt complex [(L?Co)2] ( 1 , L=[(2,6‐iPr2C6H3)NC(Me)]2) with polyarenes afforded a series of mononuclear and dinuclear complexes: [LCo(η4‐anthracene)] ( 2 ), [LCo(μ‐η4:η4‐naphthalene)CoL] ( 3 ), and [LCo(μ‐η4:η4‐phenanthrene)CoL] ( 4 ). The pyrene complexes [{Na2(Et2O)2}{LCo(μ‐η3:η3‐pyrene)CoL}] ( 5 ) and [{Na2(Et2O)3}{LCo(η3‐pyrene)}] ( 6 ) were obtained by treating precursor 1 with pyrene followed by reduction with Na metal. These complexes contain three potential redox active centers: the cobalt metal and both α‐diimine and polyarene ligands. Through a combination of X‐ray crystallography, EPR spectroscopy, magnetic susceptibility measurement, and DFT computations, the electronic configurations of these complexes were studied. It was determined that complexes 2 – 4 have a high‐spin CoI center coupled with a radical α‐diimine ligand and a neutral polyarene ligand. Whereas, the ligand L in complexes 5 and 6 has been further reduced to the dianion, the cobalt remains in a formal (I) oxidation state, and the pyrene molecule is either neutral or monoanionic. 相似文献
996.
Frontispiece: New Dual Fluorescent Probe for Simultaneous Biothiol and Phosphate Bioimaging 下载免费PDF全文
997.
Jun-Hang Jiang Can-Hui Zheng Chong-Qing Wang Juan Wang Wei Tian Chao Yang Yun-Long Song Yong Hu Ju Zhu You-Yun Zhou 《中国化学快报》2015,26(5):607-609
A series of new combretastatin-A4 analogs were synthesized, in which a six-membered ring connects the linking bridge and A ring, and their tumor cell growth and tubulin-polymerization inhibitory activity were evaluated. These compounds appear to be potential tubulin-polymerization inhibitors. Compounds 1b with amino substituted on position 3 of B ring conferred optimal bioactivity, higher than that of the lead compound 22b and equivalent to that of CA-4. The binding modes of these compounds to tubulin were obtained by molecular docking, which can explain the structure-activity relationship. The studies presented here provide a new structural type for the development of novel antitumor agents. 相似文献
998.
Exploring the factors to control Znsalen aggregation is of importance to design functional materials in catalysis, optical materials and biological imaging. In this work, we synthesized and characterized four cryptand type triZnsalen complexes and found that cryptand structure could efficiently minimize intermolecular Zn···O interaction. More importantly, encapsulated by PLGA nanoparticles, cryptand triZnsalen 1 displayed visible intracellular fluorescence whereas monomeric Znsalen 5 could not. These results provide a new access to design new luminescent materials with the potential application in optics and biological studies. 相似文献
999.
采用Schiff碱配体2-乙酰吡啶缩邻氨基苯甲酰腙(L)分别与Cd(NO3)2·4H2O和Zn(CH3COO)2·2H2O进行配位反应,得到2个配合物[Cd L(NO3)2·H2O](1)和[Zn L2](2)。分别采用1H NMR、FTIR和元素分析等手段对化合物进行了表征,并测定了2个配合物的单晶结构。结构解析表明,配合物1属于单斜晶系,P21/n空间群,配合物2属于单斜晶系,P21/c空间群。对配体和配合物的体外抑菌活性进行了初步考察,结果表明,配体L和配合物1具有一定的抑菌活性。 相似文献
1000.
采用纳米Fe3O4粒子(nano-Fe3O4)和石墨烯(Reduced Graphene Oxide,RGO)制备了nano-Fe3O4-RGO复合材料修饰玻碳电极(nano-Fe3O4-RGO/GCE),采用循环伏安法(cyclic voltammetry,CV),方波伏安法(square wave voltammetry,SWV),计时电流法(chronoamperometry,CA),计时库仑法(chronocoulometry,CC)研究了吡罗昔康(Piroxicam,PC)在此复合修饰电极上的电化学行为及电化学动力学性质。实验结果表明,与GCE相比,nano-Fe3O4-RGO/GCE对PC的电化学氧化作用有显著的促进作用,其氧化峰电流显著增加;对各种实验条件进行了优化,测得峰电流Ipa与PC浓度在2.0×10-6~2.0×10-4mol·L-1范围内呈良好的线性关系,检出限(S/N=3)为5.3×10-7mol·L-1,加标回收率为100.0%~104.0%。该方法快速,灵敏,并将nano-Fe3O4-RGO/GCE用于市售吡罗昔康片剂的测定,结果符合定量测定要求。 相似文献