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991.
利用Dashnic-Zusmanovich+矩阵的定义,通过不等式放缩技巧和Dashnic-Zusmanovich矩阵逆的无穷范数估计式得到Dashnic-Zusmanovich+矩阵线性互补问题解的误差界. 相似文献
992.
993.
Seema Yadav Sriparna Ray Ajeet Singh Shaikh M. Mobin Tapta Kanchan Roy Chandrakanta Dash 《应用有机金属化学》2020,34(11):e5942
Dinuclear gold(I)-N-heterocyclic carbene complexes were developed for the hydrohydrazidation of terminal alkynes. The gold(I)-N-heterocyclic carbene complexes 2a-2b were synthesized in good yields from silver complexes synthesized in situ, which in turn were obtained from the corresponding imidazolium salts with Ag2O in dichloromethane as a solvent. The new air-stable gold(I)-NHC complexes, 2a - 2b, were characterized using NMR spectroscopy, elemental analysis, infrared, and mass spectroscopy studies. The gold(I) complex 2a was characterized using X-ray crystallography. Bis-N-heterocyclic carbene–based gold(I) complexes 2a - 2b exhibited excellent catalytic activities for hydrohydrazidation of terminal alkynes yielding acylhydrazone derivatives. The working catalytic system can be used in gram-scale synthesis. In addition, the catalytic reaction mechanism of the hydrohydrazidation of terminal alkynes by gold(I)-NHC complex was studied in detail using density functional theory. 相似文献
994.
以β-PbO2/石墨电极为工作电极,在支持电解溶液中加入一定量待测有机物,在低于析氧电位下进行恒电位电解时,因电极表面吸附态羟基自由基的消耗速率受电解质溶液中有机物分子向电极表面的扩散过程控制,表现为阳极电流强度的增加值(ΔI)与有机物质量浓度ρ之间呈线性关系。本文研究了多种待测有机物的ΔI与ρ的线性关系,发现由于有机物种类不同造成羟基自由基消耗速率不同,因而线性比例系数有所不同。实验结果表明在测定混合水样的化学需氧量(COD)值时,应采用与待测水样具有相似有机物混合比例的标准溶液制作工作曲线,以减少测量误差。 相似文献
995.
Chemistry of Diruthenium and Dirhodium Analogues of Pentaborane(9): Synthesis and Characterization of Metal N,S‐Heterocyclic Carbene and B‐Agostic Complexes
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M. Sc. Dipak Kumar Roy M. Sc. Bijan Mondal M. Sc. R. S. Anju Prof. Sundargopal Ghosh 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(9):3640-3648
Building upon our earlier results on the synthesis of electron‐precise transition‐metal–boron complexes, we continue to investigate the reactivity of pentaborane(9) and tetraborane(10) analogues of ruthenium and rhodium towards thiazolyl and oxazolyl ligands. Thus, mild thermolysis of nido‐[(Cp*RuH)2B3H7] ( 1 ) with 2‐mercaptobenzothiazole (2‐mbtz) and 2‐mercaptobenzoxazole (2‐mboz) led to the isolation of Cp*‐based (Cp*=η5‐C5Me5) borate complexes 5 a , b [Cp*RuBH3L] ( 5 a : L=C7H4NS2; 5 b : L=C7H4NOS)) and agostic complexes 7 a , b [Cp*RuBH2(L)2], ( 7 a : L=C7H4NS2; 7 b : L=C7H4NOS). In a similar fashion, a rhodium analogue of pentaborane(9), nido‐[(Cp*Rh)2B3H7] ( 2 ) yielded rhodaboratrane [Cp*RhBH(L)2], 10 (L=C7H4NS2). Interestingly, when the reaction was performed with an excess of 2‐mbtz, it led to the formation of the first structurally characterized N,S‐heterocyclic rhodium‐carbene complex [(Cp*Rh)(L2)(1‐benzothiazol‐2‐ylidene)] ( 11 ) (L=C7H4NS2). Furthermore, to evaluate the scope of this new route, we extended this chemistry towards the diruthenium analogue of tetraborane(10), arachno‐[(Cp*RuCO)2B2H6] ( 3 ), in which the metal center possesses different ancillary ligands. 相似文献
996.
Roy Sourav Singha Sarkar Sriparna Chakraborty Debashis 《Journal of inclusion phenomena and macrocyclic chemistry》2021,100(1-2):37-37
Journal of Inclusion Phenomena and Macrocyclic Chemistry - A correction to this paper has been published: https://doi.org/10.1007/s10847-021-01060-y 相似文献
997.
998.
Manas Mahapatra Arnab Dutta Joy Sankar Deb Roy Ujjal Das Dr. Snehasis Banerjee Prof. Sanjit Dey Dr. Pijush Kanti Chattopadhyay Prof. Dilip K. Maiti Dr. Nayan Ranjan Singha 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(2):502-516
To circumvent costly fluorescent labeling, five nonconventional, multifunctional, intrinsically fluorescent aliphatic terpolymers ( 1 – 5 ) have been synthesized by C−C/C−N-coupled, solution polymerization of two non-emissive monomers with protrusions of fluorophore monomers generated in situ. These scalable terpolymers were suitable for sensing and high-performance exclusion of CuII, logic function, and bioimaging. The structures of the terpolymers, in situ attachment of fluorescent monomers, aggregation-induced enhanced emission, bioimaging ability, and super adsorption were investigated by 1H and 13C NMR, EPR, FTIR, X-ray photoelectron, UV/Vis, and atomic absorption spectroscopy, thermogravimetric analysis, high-resolution transmission electron microscopy, dynamic light scattering, solid-state fluorescence, fluorescence imaging, and fluorescence lifetime measurements, as well as by isotherm, kinetics, and thermodynamic studies. The geometries and electronic structures of the fluorophores and the absorption and emission properties of the terpolymers were examined by DFT, time-dependent DFT, and natural transition orbital analyses. For 1 , 2 , and 5 , the limits of detection were determined to be 1.03×10−7, 1.65×10−7, and 1.77×10−7 m , respectively, and the maximum adsorption capacities are 1575.21, 1433.70, and 1472.21 mg g−1, respectively. 相似文献
999.
Analysis Mathematica - In this paper, in the light of weighted sharing of sets, we investigate the possible uniqueness of meromorphic function of restricted hyper order with its linear c-shift... 相似文献
1000.
Expander graphs have been playing an important role in combinatorics and computer science over the last four decades. In recent years a theory of high dimensional expanders is emerging, but as of now all known examples of expanders (random and explicit) have unbounded degrees. The question of existence of bounded degree high dimensional expanders was raised by Gromov and by Dotterrer and Kahle. In this paper we present a new model, based on Latin squares, of 2-dimensional complexes of bounded edge degrees that are expanders with probability tending to 1. 相似文献