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排序方式: 共有1944条查询结果,搜索用时 828 毫秒
81.
Wenhao Xu Murong Wen Jingbo Yu Qihong Zhang Nikolay E. Polyakov Alexandr V. Dushkin 《Drug development and industrial pharmacy》2013,39(12):1924-1932
AbstractIn this study, complexes of kaempferol (KF) with polysaccharide arabinogalactan (AG) and disodium glycyrrhizinate (Na2GA) were prepared through mechanochemical technique to improve the solubility and bioavailability of KF. The physicochemical properties and the interactions of KF with AG/Na2GA were investigated through dissolution, SEM, XRD, and DSC studies. The reduction of particle sizes and destruction of crystal forms revealed the formation of solid dispersion which may have assisted the dissolution of the drug. The accelerated stability study showed higher stability for KF–Na2GA complex. In vivo pharmacokinetic study was performed to observe the plasma drug concentrations for KF complexes. Mechanochemical complexation of KF with AG/Na2GA improved the pharmacological activity as evident by the inhibitory potential of the complexes towards carbohydrate metabolic enzymes. In vivo studies were performed in STZ-induced diabetic mice, where the group treated with KF–AG complex showed better liver and kidney function and lower blood glucose levels than pure KF. Therefore, mechanochemical complexes of KF with polysaccharide or glycyrrhizate may serve as a promising formulation for the treatment of diabetes. 相似文献
82.
Numerical study of nonstationary three-dimensional laminar convection is performed in the model of the main element of a solar water-heating installation of the accumulation type in the process of a daily cycle of heat supply. Three-dimensional velocity fields and peculiarities of temperature distributions in the tubular element of installation that are connected with formation of temperature stratification are analyzed at different angles of the element inclination to the horizon. 相似文献
83.
V. N. Polyakov 《Russian Electrical Engineering》2009,80(9):486-490
Estimation methods and the results of an investigation of motor control modes energy efficiency in adjustable electric drives
are considered. 相似文献
84.
V. P. Bobrov V. G. Goldshtein V. S. Polyakov O. V. Solyakov 《Russian Electrical Engineering》2009,80(11):630-635
Problems in analyzing the statistical modeling of electromagnetic compatibility (EC) in processes linked with a rise in overvoltage
and its development and influence in electric mains are analyzed. Regularities in electric equipment damage and recommendations
for electromagnetic compatibility analysis with the Monte Carlo method are presented. 相似文献
85.
S. P. Polyakov 《Programming and Computer Software》2011,37(6):322-325
A computer algebra algorithm for indefinite summation of rational functions based on complete factorization of denominators
is proposed. For a given f, the algorithm finds two rational functions g, r such that f = g(x + 1) − g(x) + r and the degree of the denominator of r is minimal. A modification of the algorithm is also proposed that additionally minimizes the degree of the denominator of
g. Computational complexity of the algorithms without regard to denominator factorization is shown to be O(m
2), where m is the degree of the denominator of f. 相似文献
86.
Bobby Gillham Andrey Yankin Fionnan McNamara Charles Tomonto David Taylor Rocco Lupoi 《CIRP Annals》2021,70(1):171-174
Additive manufacturing techniques such as selective laser melting enable the production of customised components with high geometrical freedom. However, SLM results in a material condition with different properties to their conventionally manufactured counterparts. The presence of process-inherent defects can significantly impact the degradation of part performance. Hereby, a novel approach to assessing notched SLM Ti-6Al-4V material via a critical distance theory is presented. Geometrical notches of varying size are evaluated. Results show that the Theory of Critical Distances is appropriately applicable to fatigue prediction of SLM Ti-6Al-4V in its as-built state. 相似文献
87.
The present review describes the state of the problem of extracting rare earth metals from secondary raw materials, such as high-coercivity magnets, nickel–metal hydride batteries (NiMH), and phosphors of coatings of fluorescent lamps. Methods for waste processing with mineral acids and other solvents, the removal of associated impurities from rare-earth components, separation, and deep purification (mainly by solvent extraction) have been considered. Data on the industrial applications of hydrometallurgical processes for rare earth metals recycling have been presented. 相似文献
88.
89.
Grinberg V. A. Emets V. V. Maiorova N. A. Maslov D. A. Averin A. A. Polyakov S. N. Molchanov S. P. Levin I. S. Tsodikov M. V. 《Protection of Metals and Physical Chemistry of Surfaces》2019,55(1):55-64
Protection of Metals and Physical Chemistry of Surfaces - A method for the preparation of film coatings of titania doped with bismuth (Bi3+) and lead (Pb2+) ions, separately and simultaneously, has... 相似文献
90.
Grinberg V. A. Emets V. V. Mayorova N. A. Maslov D. A. Averin A. A. Polyakov S. N. Levin I. S. Tsodikov M. V. 《Protection of Metals and Physical Chemistry of Surfaces》2019,55(4):637-645
Protection of Metals and Physical Chemistry of Surfaces - A method of formation of film coatings of titanium dioxide doped by bismuth ions (Bi3+) is developed on the basis of sol–gel... 相似文献