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排序方式: 共有10000条查询结果,搜索用时 15 毫秒
991.
E. Kh. Shakhpazov I. G. Rodionova O. N. Baklanova A. I. Zaitsev D. A. Burko A. D. Gorin S. D. Zinchenko 《Metallurgist》2006,50(1-2):65-70
It is shown that the corrosion resistance of automobile sheet can be improved by ensuring that steels of this type have a
low content of corrosion-active nonmetallic inclusions (CANI). The main mechanisms responsible for the formation of CANI in
automobile sheet have been established, and recommendations have been developed to reduce their concentration in this product
• optimize the deoxidation processes that are used by ensuring that the proportions of the additions made to the steel are
consistent with the composition of the ladle slag and that certain key temperature-time parameters of these processes are
maintained
• control the composition of the ladle slag to prevent the formation of solid phases in the slag and their transfer to the
metal; certain conditions must also be observed in the argon blow and the introduction of the addtions.
Use of the above recommendations to make automobile sheet and tube steels cleaner with respect to their content of CANI and
thus help optimize out-of-furnace treatments at metallurgical and pipe plants will make it possible to improve the corrosion
resistance of metal products used in automotive manufacturing.
__________
Translated from Metallurg, No. 2, pp. 45–48, February, 2006. 相似文献
992.
The scientific community and general public can best take advantage of the benefits of 3D digital reconstructions if they are stored in a Web-accessible, easy-to-access database. We describe MorphologyNet/sup /spl copy// a Web-based digital library of realistic, 3D interactive and customizable images of anatomy currently in development at the University of Missouri-Rolla. 相似文献
993.
G. L. Brownell C. A. Burnham C. W. Stearns D. A. Chesler A.-L. Brownell M. R. Palmer 《International journal of imaging systems and technology》1989,1(2):207-217
The development of high resolution PET systems is important for the wider application of this techniques. The resolution of PET is limited by a number of physical factors such as positron range, small angle deviation, and sampling frequency. The design of the detector array and its sensitivity remain critical factors; designs incorporating analog coding have proven to be useful. PCR-I, a single plane PET system, has demonstrated the concept and has produced useful images in animal studies. PCR-II will extend the concept to a two dimensional detector array resulting in a system with high resolution and high sensitivity. 相似文献
994.
995.
N. F. Kuschevskaya A. E. Kushchevskii A. I. Oleshko 《Powder Metallurgy and Metal Ceramics》2006,45(3-4):202-206
The possibility of utilizing nanopowders of iron and Fe-Co-Ni produced bu a thermochemical method in the fabrication of sealing
composition materials is investigated. It is established that such hermetic sealing composition materials function reliably
under extremal conditions and guarantee elevated strength of adhesion to the surface of the metal and high corrosion and temperature
stability.
__________
Translated from Poroshkaya Metallurgiya, Nos. 3–4(448), pp. 112–117, March–April, 2006. 相似文献
996.
The basic principles for selecting the work regimes for diamond drilling of nonmetallic materials are presented. The process
of microcutting by a single diamond grain is examined, and relations between the components of the cutting force and the ratio
of the rate of the main motion to the feed rate are obtained on the basis of known relationships. It is shown that adaptive
control of the drilling nonmetallic materials is possible using two-circuit systems — one for feed-rate control and one for
cutting-rate.
__________
Translated from Steklo i Keramika, No. 3, pp. 28–30, March, 2007. 相似文献
997.
998.
Arrival times of seismic waves propagated to a dense array (20 three-component seismometers on a 3 × 3 km area) from natural sources beneath the Travale field, have been analysed for lateral variations which can be related to the extent of the productive reservoir. Significant teleseismic delays between sites only a few hundred meters apart correlate with productive well R9. Spatial variation of both P and S travel arrival times from local earthquakes at the edge of the array and 4 km deep beneath the reservoir consistently delineate its lateral extent to the south and east as documented by drillholes. 相似文献
999.
Discusses common presenting complaints and those of emergent significance that have an organic etiology. The following categories are discussed: head, eyes, ears, throat, neck, cardiac, respiratory, gastrointestinal, genito-urinary, musculoskeletal, and neurologic complaints. It is suggested that many therapists lack adequate medical information to suspect the presence of organic problems when symptoms are indistinguishable from psychogenic/psychosomatic problems. (4 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
1000.
R. Toledo-Marin F.A. Cruz-Perez L. Ortigoza-Guerrero 《Electronics letters》2007,43(7):399-401
A new mathematical method to analyse the performance of guard-channel-based strategies is proposed. The analysis is based on the iterative calculation of the average effective channel holding time. The method presented provides higher accuracy than alternative solutions previously reported in the literature 相似文献