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61.
由于抗生素的不当使用和细菌多药耐药的出现, 迫切需要开发新的抗菌剂. 本文制备了具有光热转换性能的正电荷半导体高分子材料及具有协同抗菌活性的半导体聚合物纳米粒子(SP-PPh3 NPs). SP-PPh3 NPs的光热转化效率为43.8%. 带正电荷的SP-PPh3 NPs可以附着在细菌上, 有助于将热量有效传递给细菌. 在热和正电荷的协同作用下, SP-PPh3 NPs对革兰氏阴性大肠杆菌(E. coli)和革兰氏阳性金黄色葡萄球菌(S. aureus)均具有抗菌活性, 其对二者的体外抑菌率分别为99.9%和98.6%. 此外, SP-PPh3 NPs具有良好的生物相容性, 对小鼠的主要器官几乎无副作用. 对细菌感染的小鼠皮肤伤口用SP-PPh3 NPs治疗12 d后, 伤口可以很好地愈合. 相似文献
62.
The formation of heterophase polymers via phase separation in the course of curing reaction in a blend of a thermosetting oligomer with a rubber modifier is considered. The interference of thermodynamic and kinetic factors that define the morphology of the material being formed is discussed. The need for a kinetic theory of cure-induced phase separation is established, and an approach of this kind is proposed. On the basis of this approach a simple quantitative criterion of deflection of the phase-separating system from the thermodynamic equilibrium is given. 相似文献
63.
Alekseev S. V. Andreev Yu. M. Losev V. F. Lubenko D. M. 《Russian Physics Journal》2020,62(11):2151-2155
Russian Physics Journal - This paper presents the results of research on parameters of the THL-100 hybrid laser system of the visible spectrum with a view to modernizing it, in order to achieve the... 相似文献
64.
The microhardness and bulk density variations with annealing temperature have been measured in NaCl crystals doped with Ca2+, Cd2+, Ni2+, and Pb2+. Both characteristics are not affected by coherent metastable precipitation while incoherent precipitation produces either hardening or softening depending on the impurity phase type (stable or metastable). The results support the suggestion that aggregates and coherent precipitates are cut through by dislocations whereas incoherent precipitates are by-passed via the Orowan looping mechanism. 相似文献
65.
V. M. Andreev O. K. Salieva V. A. Solov'ev O. V. Sulima A. M. Khammedov 《Crystal Research and Technology》1988,23(12):1531-1537
It is shown by microcathodoluminescence and electron beam induced current investigations that efficiency of radiative recombination and the values of hole diffusion lengths in nGaAs substrate increase (up to Lp ∽ 5 μm) due to an annealing under Ga Al melt. The values of the annealing critical temperature exceeding of which leeds to bulk non-radiative recombination drop as well as optimal values of annealing temperature and duration are determined. In pAlGaAs–(p-n)GaAs solar cells based on annealed substrates the values of open circuit voltage Uoc = 1.16 – 1.18 V under 500-fold concentrated solar radiation as well as values of photocurrent comparable with the best results of solar cells with epitaxial nGaAs are achieved. 相似文献
66.
R. Assenov V. A. Moshnikov D. A. Yaskov A. P. Andreev M. A. Bestaev 《Crystal Research and Technology》1987,22(9):1159-1163
By using the non-stationary thermal-probe method, investigations were carrieed out on the distribution of the coefficient of thermal electromotive force along the depth of monocrystals of lead telluride, subjected to isothermal saturating annealing in vapours of alloying compositions. The alloying composition consisted of powdered lead telluride, synthesized by the iodide method, and contained elevated concentration of the metallic component and iodine. The PbTe monocrystals were obtained from the vapour phase and had a natural cut. The results of the investigations testify to considerable changes in the concentration of the electrically active proper defects within the entire volume of the crystals, this being obviously connected with diffusion of vacancies from the crystal volume. 相似文献
67.
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69.
V. B. Petkov E. V. Bugaev P. A. Klimai M. V. Andreev V. I. Volchenko G. V. Volchenko I. M. Dzaparova D. D. Dzhappuev A. N. Gaponenko Zh. Sh. Guliev N. F. Klimenko A. U. Kudzhaev A. V. Sergeev N. S. Khaerdinov A. B. Chernyaev A. F. Yanin 《Journal of Experimental and Theoretical Physics》2010,110(3):406-416
The energy spectra and temporal characteristics of high-energy gamma-ray bursts from evaporating primordial black holes have been calculated using various evaporation models. The currently existing theoretical uncertainties in the shape of the evaporated photon spectrum are discussed. The data from the Andyrchy and Carpet-2 arrays of the Baksan Neutrino Observatory (Institute for Nuclear Research, Russian Academy of Sciences) obtained in the mode of detection of a single cosmic-ray component are used to search for cosmic gamma-ray bursts with a primary photon energy of about 8 GeV. New upper limits have been obtained for the number density of evaporating black holes in a local region of space with a characteristic size of ~10?3 pc for various evaporation models. 相似文献
70.
Mario Thevis Ines Möller Andreas Thomas Simon Beuck Grigory Rodchenkov Wolfgang Bornatsch Hans Geyer Wilhelm Schänzer 《Analytical and bioanalytical chemistry》2010,396(7):2479-2491
Since January 2009, the list of prohibited substances and methods of doping as established by the World Anti-Doping Agency
includes new therapeutics such as the peroxisome-proliferator-activated receptor (PPAR)-delta agonist GW1516, which is categorized
as a gene doping substance. GW1516 has completed phase II and IV clinical trials regarding dyslipidemia and the regulation
of the lipoprotein transport in metabolic syndrome conditions; however, its potential to also improve athletic performance
due to the upregulation of genes associated with oxidative metabolism and a modified substrate preference that shifted from
carbohydrate to lipid consumption has led to a ban of this compound in elite sport. In a recent report, two presumably mono-oxygenated
and bisoxygenated urinary metabolites of GW1516 were presented, which could serve as target analytes for doping control purposes
after full characterization. Hence, in the present study, phase I metabolism was simulated by in vitro assays employing human
liver microsomal fractions yielding the same oxygenation products, followed by chemical synthesis of the assumed structures
of the two abundant metabolic reaction products. These allowed the identification and characterization of mono-oxygenated
and bisoxygenated metabolites (sulfoxide and sulfone, respectively) as supported by high-resolution/high-accuracy mass spectrometry
with higher-energy collision-induced dissociation, tandem mass spectrometry, and nuclear magnetic resonance spectroscopy.
Since urine samples have been the preferred matrix for doping control purposes, a method to detect the new target GW1516 in
sports drug testing samples was developed in accordance to conventional screening procedures based on enzymatic hydrolysis
and liquid–liquid extraction followed by liquid chromatography, electrospray ionization, and tandem mass spectrometry. Validation
was performed for specificity, limit of detection (0.1 ng/ml), recovery (72%), intraday and interday precisions (7.7–15.1%),
and ion suppression/enhancement effects (<10%). 相似文献