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排序方式: 共有587条查询结果,搜索用时 15 毫秒
11.
S. A. Grudinkin N. A. Feoktistov K. V. Bogdanov M. A. Baranov A. V. Baranov A. V. Fedorov V. G. Golubev 《Semiconductors》2014,48(2):268-271
Isolated spherical diamond particles with embedded silicon-vacancy color centers are synthesized on a patterned surface of synthetic opal by chemical vapor deposition methods. The phase composition of the particles is determined and their structural and luminescence properties are studied. Prospects are discussed for the application of these particles as integrated spherical diamond microcavities, in which color centers are situated directly in the microcavities. 相似文献
12.
A total of 111 patients with essential hypertension (the II stage) and obesity (the II degree) were investigated for providing with vitamin B6. The functional methods used for the vitamin assay (ACT activity of red blood cells and pyrodoxale-5-phosphate effect) have revealed significant vitamin B6 deficiency in 81.1% of the patients. Vitamin B6 deficiency was intensified in the course of the dietotherapy. Correction of vitamin B6 deficiency with a therapeutic dose of pyridoxine (20 mg/day) during 20-22 days, in the presence of the diet, has promoted optimization of providing with vitamin B6: normalization of pyrodoxale-5-phosphate effect. The hypotensive effect and decrease of excessive body mass in patients who received dietotherapy and pyridoxine (20 mg/day) were more pronounced than in those who received the same diet and the multivitamin "Undevitum". 相似文献
13.
V V Vankhanen B L Smolianski? N G Bogdanov E N Stepanova L N Shatniuk N A Bukina M G Kostyleva I M Nesterova M V Dudina T G Savina 《Voprosy pitaniia》1990,(6):41-45
Providing with ascorbic acid, thiamine, riboflavin, vitamin B6 and niacin was studied in miners at deep levels before and after intake of correcting doses of vitamins. Enrichment of the food ration with vitamins produced a positive effect on the working capacity of the miners under study. The levels of vitamin consumption (vitamin-energy coefficients) have been estimated correcting the vitamin balance in miners working at deep levels. 相似文献
14.
There is considerable interest in interleaving multiple phased array antennas into a single common aperture system. Current phased array antenna technology is limited to narrowband operation, leading to the appearance of grating lobes and strong mutual coupling effects when they are incorporated into the design of a common aperture system. To overcome this obstacle, a new class of arrays, called polyfractal arrays, has been introduced that possess natural wideband properties well suited for large-scale genetic algorithm optimizations. These arrays also possess recursive beamforming properties and an autopolyploidy-based chromosome expansion that can dramatically accelerate the convergence of a genetic algorithm. In addition, a robust Pareto optimization can be applied to reduce the peak sidelobe levels at several frequencies throughout the intended operating band, leading to ultrawideband antenna array designs. Because of their lack of grating lobes, these polyfractal arrays are ideal building blocks for interleaved antenna array systems. This paper develops these concepts, first creating ultrawideband array designs based on polyfractal geometries and then interleaving these designs into a common aperture system. Several examples of interleaved systems are discussed, with one two-array system possessing a peak sidelobe level of nearly -18 dB with no grating lobes over a 20:1 bandwidth with either of the component array mainbeams steered independently up to 60deg from broadside. 相似文献
15.
Vitamin B1 in rats induced in the liver elevation of activity of metabolic enzymes of xenobiotics bound with membranes (dimethylaniline N-demethylase, aniline n-hydroxylase, aryl esterase). At the same time activity of the cytoplasmatic enzymes alcohol dehydrogenase and glutathione-S-transferase was appreciably lowered. An additional load with thiamine (20 mg/kg) led to a drop in activity of the membrane-bound enzymes. Vitamin B1 deficiency modified the effect of the inductor phenobarbital. Additional administration of vitamin B1 to thiamine-deficient animals normalized the thiamine level in the liver, and activity of hydroxylase, aryl esterase, formaldehyde dehydrogenase, and significantly decreased demethylase activity. In vitamin B1-deficient animals high detergent concentrations significantly suppressed NADH-dichlorophenol-indophenol-reductase activity, while low concentrations activated this enzyme as compared to the control. 相似文献
16.
S. P. Aleksandrova L. A. Bogdanova S. G. Sennikov A. P. Bogdanov 《Refractories and Industrial Ceramics》1990,31(1-2):9-11
Conclusions We studied the possibility of using the waste products of the aluminum industry as additives for obtaining gunite-bodies. In order to carry out guniting of the electrolytic cells, we suggested the application of the lining-slag type systems and the systems based on corundum for improving the service life of the refractory lining of these units.Translated from Ogneupory, No. 1, pp. 8–10, January, 1990. 相似文献
17.
Yu. I. Bogdanov N. A. Bogdanova K. G. Katamadze G. V. Avosopyants V. F. Lukichev 《Optoelectronics, Instrumentation and Data Processing》2016,52(5):475-485
This paper describes the model of a compound Poisson distribution for photon statistics with regard to their bunching in Fock states, thermal states, and others. The method of generating functions is used to calculate the probability distributions, moments, and correlation functions. The parameters of conditional states arising from the subtraction of photons by splitting the beam are determined. The problem of state reconstruction with regard to quadrature quantum measurements is considered. The study is aimed at developing high-precision methods for generating and controlling optical quantum states. 相似文献
18.
Metal Science and Heat Treatment - Results of a study of transportation of chromium and iron by iodine at various temperatures of diffusion chromizing of armco iron are presented. The phase... 相似文献
19.
S. G. Bogdanov E. G. Gerasimov Yu. N. Skryabin E. A. Sherstobitova V. V. Sikolenko R. Schedler A. N. Pirogov 《The Physics of Metals and Metallography》2012,113(3):228-232
Neutron-diffraction studies of a single crystal of TbNi5 have been performed. Temperature and field dependences of the intensities of the Bragg reflection (001) and magnetic satellites
(001)− and (001)+ have been determined. In the temperature range of 7–10 K, sharp changes in the intensities of both the Bragg reflection and
its satellites have been revealed. A conclusion is made that these changes are due to the existence of a magnetic transition
from an incommensurate into a lock-in structure. It has been found that at 11 K an external magnetic field μ0
H = 0.1 T oriented along the [100] axis induces the same magnetic state of the crystal as its cooling to 7 K in the absence
of a field. In an external magnetic field μ0
H = 0.4 T, there occurs a magnetic transition from the incommensurate phase with a wave vector k = 2π/c (0, 0, 0.18) into a commensurate ferromagnetic phase with k = 0. In the ferromagnetic phase, an increase in the field from 0.4 to 0.6 T is accompanied by an increase in the intensity
of the ferromagnetic reflection (001) by a factor of 1.6. This indicates the existence of strong fluctuations of the magnetization
at 0.4 T. 相似文献
20.
Fluorapatite-containing glass ceramics were synthesized on the basis of the glass-forming system SiO2–Al2O3–P2O5–CaO–CaF2. The introduction of phosphorus and fluorine containing materials, as well as the specific regime of heat treatment of the glasses gave glass ceramic materials with crystalline phases of the apatite group—fluorapatite (Ca10(PO4)6F2), apatite (Ca3(PO4)2), vitlokite (Ca9P6O24), etc. The X-ray phase analysis showed that the main phase in all the glass ceramic samples was fluorapatite. The phase composition, structure and some of the basic properties of the glass ceramic samples were determined. 相似文献