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51.
E.A. Makeeva M.N. Rumyantseva A.M. Gaskov B.A. Ismailov V.A. Vasnev 《Procedia Chemistry》2009,1(1):172-175
New hybrid materials based on nanocrystalline tin dioxide and two types of surface-immobilized polymer organosilicon structures with hydrocarbon substitutes were synthesized for gas sensors application. The sensing responses of pure SnO2 and hybrid samples were determined in the presence of NO2 (ppb range), CO (ppm range) and different humidity (RH = 15 – 95 %). Also the influence of water presence on sensor signal towards NO2 and CO was analyzed. Strong influence of nature of hydrocarbon substitutes on sensor response value towards NO2 and H2O was discovered. 相似文献
52.
53.
Ismailov Sh. M. Arapov Yu. D. Kamenev V. G. 《Radiophysics and Quantum Electronics》2021,63(8):571-581
Radiophysics and Quantum Electronics - We describe experimental studies of the recording of the relief of a diffusely reflecting surface using a shear interferometer. The interferometer uses a... 相似文献
54.
Sumana Chatterjee Bappaditya Roy Rajat Banerjee 《Polymer Degradation and Stability》2010,95(2):195-200
Extruded low-density polyethylene (LDPE) films commonly available in the market as 20-micron thick carrier bags were autoclaved, overlaid on nutrient agar plates and inoculated with BP/SU1 strain of Staphylococcus epidermis. The nutrient agar plate showed growth of the organism within two to three days. The polymer film supporting the growth of the organism showed pore formation as recorded by SEM analysis. The growth of BP/SU1 is supported by the presence of shredded LDPE as its only carbon source in inorganic salt minimal nutrient medium. The organism survives even after three months of inoculation and this is accompanied by gradual breakdown of the size of the shredded plastic as seen by light scattering. The cell-free supernatant of the organism, grown with the help of shredded plastic shows the presence of the over expressed proteins with approximate molecular weight of about 55 kDa and 35 kDa, through SDS-PAGE analysis. 相似文献
55.
V. A. Matyshak O. N. Sil’chenkova I. T. Ismailov V. F. Tret’yakov 《Kinetics and Catalysis》2010,51(3):428-437
It is demonstrated by in situ IR spectroscopy that, in methanol conversion on ZrO2 and 5% Cu/ZrO2 catalysts, methoxy groups are present on the catalyst surface, which result from O-H or C-O bond breaking in the methanol
molecule. Two types of formate complexes, localized on ZrO2 and CuO, are also observed. The formate complexes form via the oxidative conversion of the methoxy groups. There are two
types of linear methoxy groups. First-type linear methoxy groups condense with the formate complex located on CuO to yield
methyl formate and then CO and H2. Second-type methoxy groups appear as intermediate products in the formation of dimethyl ether. The main hydrogen formation
reactions are the recombination of hydrogen atoms (which result from the interconversion of surface complexes) on copper clusters
and the decomposition of methyl formate. The source of CO2 in the gas phase is the formate complex, and the source of CO is methyl formate. The effect of water vapor and oxygen the
surface reactions and product formation is discussed. 相似文献
56.
A High-Order Immersed Boundary Method for Acoustic Wave Scattering and Low-Mach Number Flow-Induced Sound in Complex Geometries 总被引:1,自引:0,他引:1
A new sharp-interface immersed boundary method based approach for the computation of low-Mach number flow-induced sound around complex geometries is described. The underlying approach is based on a hydrodynamic/acoustic splitting technique where the incompressible flow is first computed using a second-order accurate immersed boundary solver. This is followed by the computation of sound using the linearized perturbed compressible equations (LPCE). The primary contribution of the current work is the development of a versatile, high-order accurate immersed boundary method for solving the LPCE in complex domains. This new method applies the boundary condition on the immersed boundary to a high-order by combining the ghost-cell approach with a weighted least-squares error method based on a high-order approximating polynomial. The method is validated for canonical acoustic wave scattering and flow-induced noise problems. Applications of this technique to relatively complex cases of practical interest are also presented. 相似文献
57.
N. I. Baram Kh. L. Ziyaev A. I. Ismailov D. Ziyamov Yu. S. Mangutova 《Chemistry of Natural Compounds》2000,36(2):185-188
New azo derivatives of gossypol are described. Their physicochemical properties are reported. The presence of hydroxyazo- and quinonhydrazo-tautomers is proposed.A. S. Sadykov Institute of Bioorganic Chemistry, Academy of Sciences of the Republic of Uzbekistan, Tashkent, fax (99871) 162 70 71. Translated from Khimiya Prirodnykh Soedinenii, No. 2, pp. 145–148, March–April, 2000. 相似文献
58.
N. I. Baram Kh. L. Ziyaev B. Khodzhaniyazov A. I. Ismailov 《Chemistry of Natural Compounds》1999,35(1):29-32
The results are given of a study of the hydrolysis of alkyl- and heterylimines of gossypol at various pH values.A. S. Sadykov Institute of Bioorganic Chemistry, Academy of Sciences of the Republic of Uzbekistan, Tashkent, fax (371) 162 70 71. Translated from Khimiya Prirodnykh Soedinenii, No. 1, pp. 38–41, January–February, 1999. 相似文献
59.
M. A. Khodzhaeva Z. F. Ismailov E. S. Kondratenko A. S. Shashkov 《Chemistry of Natural Compounds》1982,18(1):20-24
By fractionating the total glucofructan from the bulbs ofAllium sativum L. a homogeneous glucofructan with a molecular weight of 2300 has been isolated. On the basis of its characteristics, a comparison of IR and13C NMR spectra, and the results of periodate and chromium trioxide oxidation and of methylation, it has been established that this glucofructan is a new type of compound of this class, containing both inulin (2 → 1) and levan (2 → 6) glycosidic bonds. 相似文献
60.
Rajat Kumar Pal Kamran Haider Divya Kaur William Flynn Junchao Xia Ronald M Levy Tetiana Taran Lauren Wickstrom Tom Kurtzman Emilio Gallicchio 《Journal of computer-aided molecular design》2017,31(1):29-44
As part of the SAMPL5 blinded experiment, we computed the absolute binding free energies of 22 host–guest complexes employing a novel approach based on the BEDAM single-decoupling alchemical free energy protocol with parallel replica exchange conformational sampling and the AGBNP2 implicit solvation model specifically customized to treat the effect of water displacement as modeled by the Hydration Site Analysis method with explicit solvation. Initial predictions were affected by the lack of treatment of ionic charge screening, which is very significant for these highly charged hosts, and resulted in poor relative ranking of negatively versus positively charged guests. Binding free energies obtained with Debye–Hückel treatment of salt effects were in good agreement with experimental measurements. Water displacement effects contributed favorably and very significantly to the observed binding affinities; without it, the modeling predictions would have grossly underestimated binding. The work validates the implicit/explicit solvation approach employed here and it shows that comprehensive physical models can be effective at predicting binding affinities of molecular complexes requiring accurate treatment of conformational dynamics and hydration. 相似文献