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141.
D. K. Walters S. Bhushan M. F. Alam D. S. Thompson 《Flow, Turbulence and Combustion》2013,91(3):643-667
This paper investigates a recently proposed dynamic hybrid RANS-LES framework using a general-purpose finite-volume flow solver. The new method is highly generalized, allowing coupling of any selected RANS model with any selected LES model and containing no explicit grid dependence in its formulation. Selected results are presented for three test cases: two-dimensional channel flow, backward facing step, and a nozzle flow relevant to biomedical applications. Comparison with experimental and DNS data, and with other hybrid RANS-LES approaches, highlights the advantages of the new method and suggests that further investigation is warranted. 相似文献
142.
Shikha Kumari Chandra Bhushan Mishra Danish Idrees Amresh Prakash Rajesh Yadav Md. Imtaiyaz Hassan Manisha Tiwari 《Molecular diversity》2017,21(1):163-174
A series of novel 2-(4-(4-substituted piperazin-1-yl)benzylidene)hydrazinecarboxamide derivatives has been successfully designed and synthesized to evaluate their potential as carbonic anhydrase (CA) inhibitors. The inhibitory potential of synthesized compounds against human CAI and CAII was evaluated. Compounds 3a–n exhibited \(\hbox {IC}_{50}\) values between \(1.89{-}415.1\,\upmu \hbox {M}\) against CAI and \(0.62{-}66.9\,\upmu \hbox {M}\) against CAII. Compound 3g was the most active inhibitor, with an \(\hbox {IC}_{50}\) value of \(0.62\,\upmu \hbox {M}\) against CAII. Molecular docking studies of compound 3g with CAII showed this compound fits nicely in the active site of CAII and it interacts with the zinc ion (\(\hbox {Zn}^{2+}\)) along with three histidine residues in the active site. Molecular dynamics simulation studies of compound 3g complexed with CAII also showed essential interactions which were maintained up to 40 ns of simulation. In vivo sub-acute toxicity study using 3g (300 mg/kg) was found non-toxic in adult Wistar rats. 相似文献
143.
Jordan D McIlvain T Alarcon R Beck R Bertozzi W Bhushan V Boeglin W Chen JP Dale D Dodson G Dolfini S Dow K Dzengeleski J Epstein MB Farkhondeh M Gilad S Görgen J Holtrop M Joo K Kelsey J Kim W Laszewski R Lourie R Mandeville J Margaziotis D Martinez D Miskimen R Papanicolas CN Penn S Sapp W Sarty AJ Tieger D Tschalaer C Turchinetz W Warren G Weinstein L Williamson S 《Physical review letters》1996,76(10):1579-1582
144.
The dependence of the superconducting transition temperature T(c) on nearly hydrostatic pressure has been determined to 67 GPa in an ac susceptibility measurement for a Li sample embedded in helium pressure medium. With increasing pressure, superconductivity appears at 5.47 K for 20.3 GPa, T(c) rising rapidly to approximately 14 K at 30 GPa. The T(c)(P) dependence to 67 GPa differs significantly from that observed in previous studies where no pressure medium was used. Evidence is given that superconductivity in Li competes with symmetry breaking structural phase transitions which occur near 20, 30, and 62 GPa. In the pressure range 20-30 GPa, T(c) is found to decrease rapidly in a dc magnetic field, the first evidence that Li is a type I superconductor. 相似文献
145.
The extraction of ammine complexes of Cu2+, Cd2+, Ni2+, Co2+ and Zn2+ by synthesised manganese, nickel and zinc silicates has been studied at different pH and ionic concentrations in the external
solution. It has been found that the uptake of the metal ion Co2+, Cu2+ and Zn2+ increases with increase in pH of the external solution, attains a maximum and then decreases. However, the uptake for Cd2+ and Ni2+ increases continuously. The qA values of all the silicates increases with the increase in the concentration of the exchanging ion and its order for the
investigated metal ions is Ni2+ < Co2+ < Cd2+ < Zn2+ < Cu2+. 相似文献
146.
147.
Narender K. Kaushik Bharat Bhushan Gurdeep R. Chhatwal 《Transition Metal Chemistry》1978,3(1):215-217
Summary Titanium(IV)N,N-dialkyldithiocarbamates of the type 5-Cp2Ti (S2CNR2)Cl and (5-MeCp)2Ti(S2CNR2)Cl (R = Me, Et and i-Pr) have been prepared by the reaction of di--cyclopentadienyldichlorotitanium(IV) and bis-n-methylcyclopentadienyldichlorotitanium(IV) with sodium salts of dithiocarbamic acids in refluxing dichloromethane. Molecular weight, conductance and i.r. studies show these complexes to be monomeric nonelectrolytes in which the dithiocarbamate ligands are bidentate. Therefore, pentacoordination may be assigned to titanium(IV) atom in all six complexes. Electronic and proton n.m.r. studies spectra have also been recorded for the complexes. 相似文献
148.
Different metal salts have been tried as impregnating reagents for developing TLC separation schemes for some antihistamines on silica gel 'G' plates, using a new solvent system benzene + dimethyl formamide + acetic acid (30:10:7). Spots were visualized by spraying with a solution of Dragendroff's reagent. 相似文献
149.
Szoszkiewicz R Bhushan B Huey BD Kulik AJ Gremaud G 《The Journal of chemical physics》2005,122(14):144708
Correlations between adhesion hysteresis and local friction are theoretically and experimentally investigated. The model is based on the classical theory of adhesional friction, contact mechanics, capillary hysteresis, and nanoscale roughness. Adhesion hysteresis was found to scale with friction through the scaling factor containing a varying ratio of adhesion energy over the reduced Young's modulus. Capillary forces can offset the relationship between adhesion hysteresis and friction. Measurements on a wide range of engineering samples with varying adhesive and elastic properties confirm the model. Adhesion hysteresis is investigated under controlled, low humidity atmosphere via ultrasonic force microscopy. Friction is measured by the friction force microscopy. 相似文献
150.
Traces of cadmium from relatively high amounts of nickel and copper can be separated by the selective sorption of the cadmium
ethylenediamine complex on hydrous ferric oxide. A batch chromatographic technique has been elaborated on this basis. 相似文献