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91.
G. Venkat Reddy A. Chandra Shekhar A. Ravi Kumar G. Sathaiah B. Narsaiah P. Shanthan Rao 《Journal of heterocyclic chemistry》2012,49(3):687-690
Studies on synthetic design of 7,8‐imidazole fused fluoroquinolones from 8‐amino‐6‐fluoro‐4‐hydroxy‐N‐methyl‐7‐(methyl amino)quinoline‐3‐carboxamide and ketones/carboxylic acids and their antibacterial activity. 相似文献
92.
Synthesis of 6‐Fluoro‐7‐cyclic Amino‐substituted Dicarboxylic Acid Quinolones and their Antibacterial Activity 下载免费PDF全文
A. Ravi Kumar G. Sathaiah A. Chandra Shekhar K. Raju P. Shanthan Rao B. Narsaiah Y. Kanaka Raju U. S. N. Murthy V. Srimai M. Ramesh T. Parthasarathy 《Journal of heterocyclic chemistry》2014,51(Z1):E114-E122
Novel 1‐carboxymethyl‐6‐fluoro‐7‐cyclic amino‐substituted‐4‐oxo‐1,4‐dihydroquinolone‐3‐carboxylic acids 7a , 7b , 7c , 7d , 7e , 7f , 7g , 7h , 7i , 7j , 7k , 7l , 7m , 7n were synthesized as a new class of quinolones. Ethyl‐6‐fluoro‐7‐chloro‐1,4‐dihydro‐4‐quinoline‐3‐carboxylic acid was prepared from conventional method and reacted with ethyl bromoacetate to furnish N‐carboxymethyl derivatives. The compounds were screed against various Gram‐positive and Gram‐negative bacterial strains. Antibacterial activity data is validated by molecular docking studies. 相似文献
93.
94.
Debadi Chakraborty Mohit Bajaj Leslie Yeo James Friend Matteo Pasquali J. Ravi Prakash 《ournal of non Newtonian Fluid Mechanics》2010,165(19-20):1204-1218
We compute the flow of three viscoelastic fluids (Oldroyd-B, FENE-P, and Owens blood model) in a two-dimensional channel partly bounded by a tensioned membrane, a benchmark geometry for fluid–structure interactions. The predicted flow patterns are compared to those of a Newtonian liquid. We find that computations fail beyond a limiting Weissenberg number. Flow fields and membrane shape differ significantly because of the different degree of shear thinning and molecular extensibility underlying the three different microstructural models. 相似文献
95.
Ravi P. Agarwal Donal O’Regan Svatoslav Staněk 《Central European Journal of Mathematics》2009,7(4):694-716
The paper is concerned with existence results for positive solutions and maximal positive solutions of singular mixed boundary
value problems. Nonlinearities h(t;x;y) in differential equations admit a time singularity at t=0 and/or at t=T and a strong singularity at x=0. 相似文献
96.
Release studies on niosomes containing fatty alcohols as bilayer stabilizers instead of cholesterol 总被引:4,自引:0,他引:4
Devaraj GN Parakh SR Devraj R Apte SS Rao BR Rambhau D 《Journal of colloid and interface science》2002,251(2):360-365
Monomers of some amphiphiles organize into bilayers to form liposomes and niosomes. Such bilayers are unstable or leaky and hence cholesterol is a common ingredient included to stabilize them. Cholesterol stabilizes bilayers, prevents leakiness, and retards permeation of solutes enclosed in the aqueous core of these vesicles. Other than cholesterol a material with good bilayer-stabilizing properties is yet to be identified. We have substituted cholesterol with fatty alcohols in niosomes containing polyglyceryl-3-di-isostearate (PGDS) and polysorbate-80 (PS-80) to explore their membrane-stabilizing property via permeation studies. Niosomes of polyglyceryl-3-di-isostearate, fatty alcohol/cholesterol, and polysorbate were prepared by ether injection method. Aqueous solution of ketorolac tromethamine (KT) was entrapped in them. The effects of alkyl chain length of fatty alcohols (C(12), C(14), C(16), C(18), and C(16+18)), of acyl chain length of polyoxyethylene sorbitan monoester surfactants, and of the molar ratio of lipid mixture on the release rate of ketorolac from niosomes were assessed by employing modified dissolution-dialysis method. Niosomes with cholesterol or fatty alcohols have exhibited a common release pattern. Niosomes containing fatty alcohol showed a considerably slower release rate of KT than those containing cholesterol. Based on the release rate, fatty alcohols can be ranked as stearyl相似文献
97.
Ravi P. Agarwal 《Journal of Computational and Applied Mathematics》1983,9(4):315-325
The paper deals with some general iterative methods in n-metric spaces. The obtained results are more explicit than those known in the literature and provides error estimates when the sequence obtained on a floating-point system starts oscillating. A stopping criteria and error estimates at that stage are provided. An application to multi-point boundary value problems is also given. 相似文献
98.
Relative importance of hydrogen bonding and coordinating groups in modulating the zinc-water acidity
Mareque-Rivas JC Prabaharan R de Rosales RT 《Chemical communications (Cambridge, England)》2004,(1):76-77
The presence of second-sphere -NH(2) groups in the proximity of a zinc(ii)-bound water molecule enhances its acidity by ca. 2 pK(a) units. 相似文献
99.
Karajanagi SS Vertegel AA Kane RS Dordick JS 《Langmuir : the ACS journal of surfaces and colloids》2004,20(26):11594-11599
We have examined the structure and function of two enzymes, alpha-chymotrypsin (CT) and soybean peroxidase (SBP), adsorbed onto single-walled carbon nanotubes (SWNTs). SBP retained up to 30% of its native activity upon adsorption, while the adsorbed CT retained only 1% of its native activity. Analysis of the secondary structure of the proteins via FT-IR spectroscopy revealed that both enzymes undergo structural changes upon adsorption, with substantial secondary structural perturbation observed for CT. Consistent with these results, AFM images of the adsorbed enzymes indicated that SBP retains its native three-dimensional shape while CT appears to unfold on the SWNT surface. This study represents the first in depth investigation of protein structure and function on carbon nanotubes, which is critical in designing optimal carbon nanotube-protein conjugates. 相似文献
100.
The Integrating Sphere Integrating Nephelometer is a novel and unique reciprocal nephelometer that uses an integrating sphere with attached truncation-reduction tubes to contain the sample volume and to integrate the scattered light. Its main advantage compared with current integrating nephelometers is a sevenfold reduction in truncation angle, which reduces errors in measured scattering from large particles. Additional features include improved sampling efficiency for large particles and a well-defined operating wavelength. 相似文献