排序方式: 共有55条查询结果,搜索用时 0 毫秒
1.
TK Cherniaeva NA Matveeva IuG Kuzmichev MP Gracheva 《Canadian Metallurgical Quarterly》1997,36(3):26-28
Nuchal screening has the following advantages: Non invasive. First trimester procedure. Results are obtained quickly. 80-90% detection rate for Down's Syndrome. 相似文献
2.
In the 1980s researchers of the All-Russia Institute of Light Alloys and the “Komposit” Research and Production Association developed a high-strength weldable corrosion-resistant alloy based on the Al - Zn - Mg - Cu - Sc - Zr system. The alloy was graded 1970 and used for fabricating pilot batches of sheets, plates, sections, and pressed preforms. Results of studies of the structure and properties of these semiproducts and their welded joints are presented. Alloy 1970 was initially designed for the purpose of spacecraft engineering. In recent years the aircraft industry has shown interest in high-strength weldable alloys for this purposes. Sheets from alloy 1970 were studied from the standpoint of their applicability as an aircraft material.__________Translated from Metallovedenie i Termicheskaya Obrabotka Metallov, No. 4, pp. 10 – 17, April, 2005. 相似文献
3.
4.
Scandium alloying of aluminum alloys can substantially improve their operating properties and weld-ability. Commercially scandium-alloyed alloys have been developed for the Al - Mg, Al - Zn - Mg, and Al - Mg - Li systems. The scandium alloying of aluminum alloys containing copper as an alloying component should be performed carefully, because scandium can produce a chemical compound with copper. This worsens the strength properties of preforms and decreases their plasticity and fracture toughness due to the increased volume fraction of the excess phases. In this work, conditions for scandium alloying are determined for the copper-containing alloys D16 and 1933.Translated from Metallovedenie i Termicheskaya Obrabotka Metallov, No. 2, pp. 23 – 27, February, 1995. 相似文献
5.
AD Lelianov IuG Novikov GA Rusanov NE Siniavskaia 《Canadian Metallurgical Quarterly》1976,116(4):24-28
In experiments on 50 dogs with toxic acute edema of the lung, induced with intravenous injection of 0.1% silver nitrate, the authors have studied the efficacy of accessory artificial circulation and "conservative" therapy. During the perfusion a discharge of the right portions, adequate extracorporeal gas metabolism, normalization of blood gas and acid-base balance were noted; an intensity of pulmonary edema is descreased. An intensive therapy for pulmonary edema was found to be more effective in association of "conservative" treatment with venoarterial perfusion and blood oxygenation. 相似文献
6.
7.
S. V. Dobatkin V. V. Zakharov A. Yu. Vinogradov K. Kitagawa N. A. Krasil’nikov T. D. Rostova E. N. Bastarash 《Russian Metallurgy (Metally)》2006,(6):533-540
The possibility of formation of a nanocrystalline structure (with a grain size smaller than 100 nm) in four Al-Mg-Sc alloys with 3.1–5.9% Mg during severe plastic deformation by torsion at a hydrostatic pressure of 6 GPa (high-pressure torsion (HPT)) has been studied. Room-temperature HPT of the alloys is shown to produce a nanocrystalline structure if the magnesium content is more than 4% (in the range 0.16–0.31% Sc). As the magnesium content increases, the grain size decreases and is minimal (40–50 nm) in a 01570 alloy with 5.9% Mg and 0.3% Sc. The structure of the HPT-processed 01570 alloy remains nanocrystalline upon heating to 200°C or at a deformation temperature as high as 200°C. Postdeformation heating is found to cause aging processes. The hardening of all the Al-Mg-Sc alloys is maximal after HPT at 20°C followed by aging at 300°C. 相似文献
8.
We present a modified Beth-Tait model that takes into account the change in size and density of the material in the core of a nuclear reactor during a serious nuclear accident accompanied by reactor breakdown. The calculation results for fission pulse parameters are compared with those obtained by traditional Bethe-Tait models.Russian Research Institute of Experimental Physics, Arzamas 16 607200. Translated from Fizika Goreniya i Vzryva, Vol. 30, No. 6, pp. 103–114, November–December, 1994. 相似文献
9.
10.
IuG Parkhomenko OA Tishkevich TG Barkhina SN Potekaev NS Potekaev 《Canadian Metallurgical Quarterly》1998,60(5):66-68
A unique case of generalized bacillary angiomatosis (BA) in a patient who died of HIV infection is described. Apart from widely spread skin lesions there were also manifestations in the brain, lungs, heart, esophagus and intestine. Gram-negative bacteria were found in the histological sections. Oval and roundish bacteria with a predominantly perivascular location were found electron microscopically in the archives material. 相似文献