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121.
122.
V. I. Chemodanov N. V. Bobyleva N. G. Chelnokova N. Yu. Sokolova 《Power Technology and Engineering (formerly Hydrotechnical Construction)》2002,36(3):123-131
Prospects of development of the energy economy in Russia are considered up to 2020. The proportion of thermal power plants (TPP) in the structure of the generating capacity of Russia amounts to about 70% (147 mln kW). The proportion of gas in the structure of fuel consumed by TPP amounts to 64%. It is predicted that the fraction of high-quality kinds of fuel (gas and fuel oil) will decrease in the considered period due to maximum involvement of coal in the fuel balance and wider use of combined-cycle and gas-turbine technologies that provide a lower specific consumption of fuel. It is planned to resort to advanced technologies both for reconstructing existing plants and erecting new ones. This paper deals with problems of fuel supply of fossil-fuel-fired thermal power plants in the light of the evolution of the energy economy of Russia. The demand of TPP for different kinds of fossil fuel, i.e., gas, coal, and fuel oil, is estimated for the whole of the country and for its regions according to two variants of development of the generating capacity with planned commissioning of combined-cycle plants with a total output of 32 mln kW and gas-turbine plants with a total output of 61 mln kW in the period of up to 2020. The tasks of the fuel policy to be solved in the considered period are presented. 相似文献
123.
MP Saunders AJ Salisbury KJ O'Byrne L Long RM Whitehouse DC Talbot EB Mawer AL Harris 《Canadian Metallurgical Quarterly》1997,82(12):4044-4048
The treatment of cancer patients with conventional chemotherapy is sometimes associated with severe systemic toxicity and only a minimal survival benefit. Because of this, new less toxic and more efficacious treatments have been sought. 8-Chloro-cAMP (8-Cl-cAMP) is one of a new generation of anticancer drugs that act at the level of signal transduction. In preclinical models, 8-Cl-cAMP modulates protein kinase A (PKA) leading to growth inhibition and increased differentiation of cancer cells. 8-Cl-cAMP was given to 16 patients with advanced cancer as an infusion via an indwelling subclavian venous catheter. We showed that 8-Cl-cAMP had a parathyroid hormone-like effect leading to increased synthesis of renal 1,25-dihydroxyvitamin D [up to 14 times the baseline value, median 3.6 times; P = 0.00001 (Student's paired t test)]. This produced the dose-limiting toxicity of reversible hypercalcemia that could not be controlled by the administration of either pamidronate or dexamethasone. The treatment was otherwise well tolerated, and other cAMP-dependent pathways (cortisol and TSH) were not affected, emphasizing the marked differences between organs in their sensitivity to this cAMP analog. Our results have shown that 8-Cl-cAMP is biologically active, and it is feasible that if the hypercalcemia can be controlled, then this drug may have a role as a single agent, or as a short infusion between cycles of chemotherapy. 相似文献
124.
Conclusions 1. Based on the above discussion it can be concluded that disintegration of mineral raw materials by powerful impact of SHF
is promising because disintegration of these materials ensures retention of the original size of the structural units of the
mineral as well as fairly good separation into the mineral components.
2. Further studies of rocks, which are useful fossil mineral raw materials, will allow us to optimize specific conditions
of their disintegration.
State University of Mining, St. Petersburg, and Institute of Geology of the Kola Scientific Center, Russian Academy of Sciences,
Apatity. Translated from Fiziko-Tekhnicheskie Problemy Razrabotki Poleznykh Iskopaemykh, Vol. 33, No. 4, pp. 95–99, July–August
1997. 相似文献
125.
S. O. Slipchenko A. A. Podoskin N. A. Pikhtin Z. N. Sokolova A. Y. Leshko I. S. Tarasov 《Semiconductors》2011,45(5):663-667
Threshold conditions for generation of a closed mode in the crystal of the Fabry-Perot semiconductor laser with a quantum-well
active region are analyzed. It is found that main parameters affecting the closed mode lasing threshold for the chosen laser
heterostructure are as follows: the optical loss in the passive region, the optical confinement factor of the closed mode
in the gain region, and material gain detuning. The relations defining the threshold conditions for closed mode lasing in
terms of optical and geometrical characteristics of the semiconductor laser are derived. It is shown that the threshold conditions
can be satisfied at a lower material gain in comparison with the Fabry-Perot cavity mode due to zero output loss for the closed
mode. 相似文献
126.
Geints YE Zemlyanov AA Kabanov AM Bykova EE Apeksimov DV Bukin OA Sokolova EB Golik SS Ilyin AA 《Applied optics》2011,50(27):5291-5298
We report on the experiments on the interaction of gigawatt femtosecond laser pulses with suspended millimeter-sized water droplets. The transparent droplets experienced laser-induced breakdown and explosive boiling up and emitted a broadband radiation. This radiation covers the spectral range from 450 to 1100?nm and consists of the spectrum of laser pulse scattered and transformed by the droplet due to self-phase modulation and plasma emission produced in water during photoionization. The droplet emission spectrum showed remarkable broadening at all viewing angles and is maximal in the direction of the laser exit from the droplet. The enlargement of the droplet results in additional spectral spreading of the emitted radiation. The depth and amount of laser pulse spectral self-transformations upon propagation through the water droplet are simulated by means of numerical calculations. 相似文献
127.
N. A. Pikhtin A. V. Lyutetskiy D. N. Nikolaev S. O. Slipchenko Z. N. Sokolova V. V. Shamakhov I. S. Shashkin A. D. Bondarev L. S. Vavilova I. S. Tarasov 《Semiconductors》2014,48(10):1342-1347
The effect of temperature delocalization in semiconductor lasers (emission wavelength λ = 1060 nm) based on symmetric and asymmetric separate-confinement heterostructures fabricated by metal-organic vapor-phase epitaxy (MOVPE) is studied. Experimental and calculated estimates show that the carrier concentration in the waveguide increases by an order of magnitude when the temperature of a semiconductor laser is raised by ~100°C. It is found that an increase in the temperature of the active zone leads to enhancement of the temperature delocalization of both electrons and holes. It is shown that the delocalization of holes begins at higher temperatures, compared with that of electrons. It is demonstrated experimentally that the onset of temperature delocalization depends on the threshold carrier concentration in the active region of a laser at room temperature. It is found that raising the energy depth of the active region by choosing the waveguide material makes it possible to fully suppress the temperature-delocalization process up to 175°C. 相似文献
128.
S. A. Agapov L. N. Bogachek V. Ya. Grubman S. V. Gutovskii V. I. Kondrat'ev A. A. Kontsevoi L. N. Korchagin A. B. Koshelev I. S. Krasheninnikov S. S. Kurochkin V. V. Lysenko A. T. Mazalov V. V. Mashkov A. I. Musorin N. R. Nigmatullin G. N. Raspopin I. V. Sokolova S. G. Tsypin 《Atomic Energy》1987,62(5):350-356
129.
TM Wickizer E Wagner A Cheadle D Pearson W Beery J Maeser B Psaty M VonKorff T Koepsell P Diehr EB Perrin 《Canadian Metallurgical Quarterly》1998,76(1):121-147
The Community Health Promotion Grants Program, sponsored by the Henry J. Kaiser Family Foundation, represents a major health initiative that established 11 community health promotion projects. Successful implementation was characterized by several critical factors: (1) intervention activities; (2) community activation; (3) success in obtaining external funding; and (4) institutionalization. Analysis of the program was based on data from several sources: program reports, key informant surveys, and a community coalition survey. Results indicate that school-based programs focusing on adolescent health problems were the most successful in reaching the populations they were targeting. The majority of the programs were able to attract external funding, thereby adding to their initial resource base. The programs were less successful in generating health promotion activities and in achieving meaningful institutionalization in their communities. 相似文献
130.
The purpose of the investigation was to examine the diagnostic value of various symptoms, clinical findings, erythrocyte sedimentation rate (ESR) and serum C-reactive protein (CRP) in acute maxillary sinusitis using the aspiration of purulent or mucopurulent from the sinus of a patient with a pathological CT-scanning as the golden standard. Of 174 patients with suspected acute maxillary sinusitis seen in general practice we found 70% to have a pathological CT-scanning and 53% to have pus or mucous pus in the sinus aspirate. Only the ESR and CRP level were found to be significantly and independently associated with a positive diagnosis as defined by the golden standard. A clinical criterion based on either an elevated ESR and/or CRP level in a patient with pain related to the maxillary sinus region had sensitivity of 0.82, a specificity of 0.57, a positive predictive value of 0.68 and a negative predictive value of 0.75, and was diagnostically superior to the clinical examination. The investigation also confirms that this disease is most likely overdiagnosed in general practice. 相似文献