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991.
BJÖRN O. ROOS 《Molecular physics》2013,111(1-2):87-91
Results are presented from a theoretical study of the × 6Σ+, A 6Σ+ and 6Δ electronic states of CrH using multiconfiguration second-order perturbation theory in the multi-state formalism (MS-CASPT2). It is shown that the results for the spectroscopic constants and radiative lifetimes for the A state are in agreement with experiment and an earlier multireference configuration interaction study only if the two close lying × and A states are allowed to interact at a level of approximation that includes dynamic correlation. 相似文献
992.
Serkan Dayan Cevahir Altinkaynak Nilgün Kayaci Şengül Dilem Doğan Nalan Özdemir Nilgün Kalaycioglu Ozpozan 《应用有机金属化学》2020,34(3):e5381
Simple fabrication of organic–inorganic hybrid nanoflowers (TPP@CuhNfs and TPP@CohNfs) was achieved with tetraphenylporphyrin (TPP) as organic counterpart and Cu2+ or Co2+ ions as inorganic materials via a green route, with lower cost and controlled pH. The effect of pH levels and TPP concentrations on the morphology of the TPP@CuhNfs and TPP@CohNfs materials was examined by scanning electron microscopy (energy-dispersive X-ray [EDX]). The formation and chemical structures of TPP@CuhNfs and TPP@CohNfs were evaluated using Fourier transform infrared. Elemental analyses of these hybrid nanoflowers were carried out by EDX. The fabricated TPP@CuhNfs and TPP@CohNfs nanomaterials under optimum conditions act as effective reusable catalysts for the hydrogenation of nitroanilines in aqueous media at ambient temperature. The time-dependent hydrogenation can be easily monitored spectrophotometrically and verified by 1H-nuclear magnetic resonance. These types of the catalytic reaction or system are recorded to be useful toward the hydrogenation of nitroanilines, regardless of the position and type of substrate. Moreover, TPP@CuhNfs and TPP@CohNfs catalysts demonstrated a type of metal ions-dependent catalytic efficiency toward hydrogenation of nitroanilines (organic pollutants), with TPP@CuhNfs found to be more effective than TPP@CohNfs. However, both catalysts containing Cu2+ and Co2+ ions showed good performance and can be reused at least five times without a significant decline in yield. The presented approach based on hybrid nanoflowers provides as a low cost and ecofriendly method (green route) for different catalytic hydrogenations. 相似文献
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Purification and characterization of organic solvent stable serine alkaline protease from newly isolated Bacillus circulans M34
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A protease from newly isolated Bacillus circulans M34 was purified by Q‐Sepharose anion exchange chromatography and Sepharose–bacitracin affinity chromatography followed by (NH4)2SO4 precipitation. The molecular mass of the purified enzyme was determined using SDS–PAGE. The optimum pH and temperature for protease activity were 11 and 50°C, respectively. The effect of various metal ions on protease activity was investigated. Alkaline protease from Bacillus circulans M34 wase activated by Zn2+, Cu2+ and Co2+ up to 31%. The purified protease was found to be stable in the organic solvents, surfactants and oxidizing agent. The substrate specificity of purified protease was investigated towards different substrates. The protease was almost completely inhibited by the serine protease inhibitor phenylmethanesulfonyl fluoride. The kinetic parameters of the purified protease, maximum rate (Vmax) and Michaelis constant (Km), were determined using a Lineweaver–Burk plot. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
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Synthesis,spectral, theoretical studies and in vitro antimicrobial activities of novel diphenyltin(IV) complexes of Schiff bases derived from phenacylamine
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Gökhan Şirikci Nilgün Ancın Selma Gül Öztaş Gülgün Yenişehirli Nurşen Altuntaş Öztaş 《应用有机金属化学》2014,28(7):537-544
A series of new diphenyltin(IV) complexes of the type Ph2SnL (L1: N‐phenacyl‐5‐bromosalicylideneimine, Ph2SnL1; L2: N‐phenacyl‐3,5‐dichlorosalicylideneimine, Ph2SnL2; L3: N–phenacyl‐4‐methoxysalicylideneimine, Ph2SnL3) were synthesized and characterized by elemental analysis, IR, 1H, 13C, 119Sn NMR spectroscopy and mass spectrometry techniques. The C―Sn―C angles in the complexes were calculated using equations with the 1J(117/119Sn―13C) values from 13C NMR spectra. The possible structures, NMR and electronic properties of the studied molecules were calculated through density functional theory and results compared with experimental data. All the complexes were found to be mildly active against several microorganisms and some fungi. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
998.
Alexander Pöcheim Dr. Gül Altınbaş Özpınar Prof. Dr. Thomas Müller Dr. Judith Baumgartner Prof. Dr. Christoph Marschner 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(71):17252-17260
Reaction of a 2,5-dilithiated silole with excess dichlorodimethylsilane gives the respective 2,5-bis(chlorodimethylsilyl) substituted silole. This compound can be converted to 2,5-bis(oligosilanyl) substituted siloles by addition of a suitable oligosilanide. In the UV spectra of the thus obtained compounds the lowest energy absorptions are bathochromically shifted compared to the absorptions of the two constituents, namely the 2,5-disilyl substituted silole and a trisilane. The bathochromic shift is interpreted as being caused by a mixed σ-conjugation/cross-hyperconjugation. This assumption is supported by TD-DFT calculations, which show a significant contribution from Si−Si bonds to the HOMO of the molecule. 相似文献
999.
RAVI RAMAMURTI RAINALD LÖHNER WILLIAM C. SANDBERG 《International Journal of Computational Fluid Dynamics》2013,27(1):83-99
A 3-D incompressible unsteady flow solver based on simple finite elements with adaptive remeshing and grid movement for both moving and deforming surfaces is described. We demonstrate the combination of adaptive remeshing techniques with the incompressible flow solver with the computation of flow past an eel in 2-D and a blue-fin tuna in 3-D. The flow past a swimming tuna was computed for two extreme cases of the caudal fin frequency and swimming speed. A grid refinement study was performed and a grid converged solution for the force produced by the caudal fin was obtained. 相似文献
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