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991.
B. L. Bozhenko L. I. Bedenko V. L. Kovtun G. G. Chernyshov 《Journal of Engineering Physics and Thermophysics》1993,64(4):328-333
An analysis of the kinetics of gas dissolution in a liquid metal flow is performed. It is shown that due to a high pouring rate and specific surface of the flow, the flow in the arc of molten filler metal, as distinct from the flow of liquid metal during its pouring, leads to intense saturation of the melt with gas.Volgograd Branch of the Novocherkassk Polytechnic Institute. Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 64, No. 4, pp. 414–420, April, 1993. 相似文献
992.
P Lund-Johansen I Hjermann BM Iversen E Thaulow 《Canadian Metallurgical Quarterly》1993,113(6):732-735
Alpha-receptor blockers reduce blood pressure by blocking of the alpha 1-receptors in the smooth muscle cells in the arteriolar walls. The heart pump function is not disturbed. Most studies have shown that the alpha-receptor blockers induce a reduction in plasma-triglycerides and an increase in the ratio between HDL- and LDL-cholesterol. They do not interfere with the metabolism of electrolytes, glucose or uric acid and have no negative effect on pulmonary function. Although long-term use does not induce a permanent increase in heart rate, some patients respond to initial therapy with faster heart rate and palpitations. The alpha-receptor blockers should not be used in patients with coronary heart disease if the patient is not on chronic beta-blockade. When these precautions are followed, the alpha-blockers can be used as first-line treatment--just like ACE-inhibitors and calcium-antagonists. 相似文献
993.
994.
E. V. Chernenko L. F. Afanas'eva N. I. Vaganova 《Combustion, Explosion, and Shock Waves》1995,31(6):635-638
It is shown that ignition may occur under light frictional pressure. In the case of friction applied to a powder, there are
two limits of ignition in terms of the frictional pressure. A frictional approach permits a high degree of compaction of powder
at low frictional pressure (∼10 kg/cm2). The influence of the material of the frictional body on sample heating and ignition is investigated. Activation of chemically
active powder under the action of friction is observed. A discussion of the results is presented.
Institute of Structural Macrokinetics, Russian Academy of Sciences, Chernogolovka. Translated from Fizika Goreniya i Vzryva,
Vol. 31, No. 6, pp. 14–19, November–December, 1995. 相似文献
995.
Translated from Steklo i Keramica, No. 3, pp. 2–5, March, 1993. 相似文献
996.
The uniqueness of the determination of carbon and nitrogen diffusion coefficients is found for the process of carbonitriding with complete and abbreviated information on the concentration fields.M. V. Lomonosov Moscow State University, Russia. Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 66, No. 4, pp. 480–483, April, 1994. 相似文献
997.
É. I. Golovko G. N. Makarenko R. F. Voitovich V. B. Fedorus 《Powder Metallurgy and Metal Ceramics》1994,32(11-12):917-920
Boron silicide and compounds based on it containing titanium, chromium, nickel, and yttrium and scandium oxides are studied for their oxidation in air from room temperature to 1300°C. It is shown that chromium boride markedly improves the heat resistance of B4Si over a wide temperature range (700–1300°C) probably as a result chromium-oxide dissolution in borosilicate glass and alteration of its structure. A favorable effect of yttrium and scandium oxides as well of nickel silicide appears at above 100°C as a result of forming complex oxide compounds in the scale. 相似文献
998.
A case is presented of a 3 1/2-year-old girl with a clinical picture of very severe psychomotor retardation, autistic behavior, and repetitive convulsive episodes starting in the neonatal period and resistant to any pharmacological treatment. Electroencephalography showed generalized abnormalities. Magnetic resonance imaging of the brain disclosed arachnoid cysts in both temporal fossae with marked hypoplasia of both temporal lobes. It is proposed that the severity of symptoms is related to the magnitude of underlying anatomical lesions as well as the associated intractable epilepsy. 相似文献
999.
1000.
Olcay I. Unver 《国际水资源开发杂志》1992,8(4):248-256
An automatic self‐correction scheme is presented for online adjustment of stream‐flow forecasts during simulation of river systems with regulating structures, when actual flow data for interior points are available in real time. Another scheme is presented which allows for the modelling of channel losses due to physical effects such as evapotranspiration, bank storage and diversions. A previously developed river simulation/reservoir management model has been modified to include both schemes. The model is particularly useful for real‐time, short‐term flood forecasting and reservoir operation. The model application is made to the Lower Colorado River in Texas. 相似文献