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31.
Dhoolesh Gangaram Kokare Krishna Naik Anupama Nevrekar Avinash Kotian Vinayak Kamat Vidyanand K. Revankar 《应用有机金属化学》2016,30(4):181-187
Mononuclear divalent complexes of Co, Ni, Cu and Zn derived from a benzofuran‐based novel hydrazone tridentate ligand were synthesized and characterized using various spectroscopic methods. Elemental analysis reveals that the metal‐to‐ligand ratio is 1:2 which is supported by mass spectrometry results. Conductivity measurements suggest that all the complexes are non‐electrolytic in nature. The ligand and complexes were evaluated for their antimicrobial potency. Bioassay of all hydrazone chelates shows enhanced activity as compared to that of the ligand. The complex with cobalt ion as the metal centre shows better activity against fungi than the standard. Also, ligand and complexes were screened for antituberculosis activity; some analogues (Ni, Cu, Zn) are eight times more active than the standard. Both ligand and complexes show moderate ability to cleave calf thymus DNA. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
32.
Heinz J. Robota Laura A. Richard Soumitra Deshmukh Steve LeViness Daniele Leonarduzzi Diarmid Roberts 《Catalysis Surveys from Asia》2014,18(4):177-182
Each process configuration for practicing the Fischer–Tropsch synthesis places demands particular to that configuration on the catalyst to be used. We discuss how a particular catalyst, prepared by the OMX (organic matrix combustion) method, when used in conjunction with the Velocys microchannel reactor system, results in a very stable, high performance Fischer–Tropsch synthesis system. With the ability to remove heat far more effectively than a conventional reactor system, this microchannel reactor requires a catalyst with much higher volumetric reactive site density. Further, with such a high volumetric reaction rate, mass transfer effects will be important in both the observed activity and selectivity of the operating catalyst. Nevertheless, the catalyst prepared using the OMX method exhibits an apparent turnover frequency which is considerably higher than reported for other catalysts in the literature. In addition to high activity, an economically useful catalyst must exhibit a stable, high selectivity for liquid products and be able to recover near-fresh performance using a regeneration approach which can be carried out with the catalyst in-place. An example of such a stable, multiply regenerated catalyst is given. Finally, further development has focused on a catalyst with even higher C5+ selectivity. 相似文献
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34.
A sharp‐interface immersed boundary framework for simulations of high‐speed inviscid compressible flows 下载免费PDF全文
Shuvayan Brahmachary Ganesh Natarajan Vinayak Kulkarni Niranjan Sahoo 《国际流体数值方法杂志》2018,86(12):770-791
A new finite‐volume flow solver based on the hybrid Cartesian immersed boundary (IB) framework is developed for the solution of high‐speed inviscid compressible flows. The IB method adopts a sharp‐interface approach, wherein the boundary conditions are enforced on the body geometry itself. A key component of the present solver is a novel reconstruction approach, in conjunction with inverse distance weighting, to compute the solutions in the vicinity of the solid‐fluid interface. We show that proposed reconstruction leads to second‐order spatial accuracy while also ensuring that the discrete conservation errors diminish linearly with grid refinement. Investigations of supersonic and hypersonic inviscid flows over different geometries are carried out for an extensive validation of the proposed flow solver. Studies on cylinder lift‐off and shape optimisation in supersonic flows further demonstrate the efficacy of the flow solver for computations with moving and shape‐changing geometries. These studies conclusively highlight the capability of the proposed IB methodology as a promising alternative for robust and accurate computations of compressible fluid flows on nonconformal Cartesian meshes. 相似文献
35.
Jingshan S. Du Peng‐Cheng Chen Dr. Brian Meckes Dr. Zhuang Xie Jinghan Zhu Yuan Liu Prof. Vinayak P. Dravid Prof. Chad A. Mirkin 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2017,129(26):7733-7737
Multicomponent nanoparticles can be synthesized with either homogeneous or phase‐segregated architectures depending on the synthesis conditions and elements incorporated. To understand the parameters that determine their structural fate, multicomponent metal‐oxide nanoparticles consisting of combinations of Co, Ni, and Cu were synthesized by using scanning probe block copolymer lithography and characterized using correlated electron microscopy. These studies revealed that the miscibility, ratio of the metallic components, and the synthesis temperature determine the crystal structure and architecture of the nanoparticles. A Co‐Ni‐O system forms a rock salt structure largely owing to the miscibility of CoO and NiO, while Cu‐Ni‐O, which has large miscibility gaps, forms either homogeneous oxides, heterojunctions, or alloys depending on the annealing temperature and composition. Moreover, a higher‐ordered structure, Co‐Ni‐Cu‐O, was found to follow the behavior of lower ordered systems. 相似文献
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37.
A series of novel imidazo[2,1‐b][1,3,4]thiadiazole fused pyridazinones have been synthesized in moderate yields by the reaction of 2‐alkyl/arylimidazo[2,1‐b] [1,3,4]thiadiazole‐6‐carbohydrazides under Vilsmeier–Haack reaction conditions. This simple methodology has utility for the synthesis of various fused heterocyclic systems. 相似文献
38.
M. B. Deshmukh S. D. Jadhav A. R. Mali A. W. Suryawanshi P. V. Anbhule S. S. Jagtap 《合成通讯》2013,43(23):2967-2971
The conjugate addition of organomanganese reagents to α,β‐unsaturated aldehydes and allylic bisacetate in presence of Me3Si‐Cl and tetrakis acetonitrile copper(I) tetrafluroborate is described. 相似文献
39.
The title compound 1 has been prepared from (+)-3-carene (2) and found to have the same order of activity as its IR-cis isomer 3 reported by us earlier1 The key intermediate methyl IR-trans-2, 2-dimethyl-3-(2-oxopropyl)cyclopropanecarboxylate (4) has been characterised. 相似文献