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排序方式: 共有10000条查询结果,搜索用时 15 毫秒
991.
A simple and accurate analysis of a single-mode optical fibre interferometric displacement detection technique is resented. This analysis is in good agreement with experimental measurements, and shows that angular alignment between the fibre and the sensor is the most critical parameter. 相似文献
992.
993.
994.
The conclusions are put forward that are adopted by a discussion group preparing the framework for a limitation policy of the radon problem in Belgium. Existing and future situations are treated in a coherent policy that is adequate for practical implementation. An action level is defined, together with a hierachy of levels for new constructions. The decision logic for the acceptance of building materials is explained. 相似文献
995.
P. V. Prosuntsov S. V. Reznik 《Journal of Engineering Physics and Thermophysics》1985,49(6):1458-1462
A method is proposed for determining the thermophysical properties of translucent scattering materials in the nonsteady heating regime.Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 49, No. 6, pp. 977–982, December, 1985. 相似文献
996.
V. A. Pilipovich V. L. Malevich G. D. Ivlev V. V. Zhidkov 《Journal of Engineering Physics and Thermophysics》1985,48(2):228-233
On the basis of a numerical solution of the Stefan problem, the dynamics of nanosecond laser annealing of silicon is investigated.Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 48, No. 2, pp. 306–312, February, 1985. 相似文献
997.
A three-stage study has been carried out with rainbow trout (Oncorhyncus mykiss) to develop analytical approaches which can provide a fingerprint for tainting by oil sands chemicals from process-affected waters and natural sources. The objective was to find a simpler alternative to sensory evaluation. In the first stage, a set of seven test compounds was added to fish tissue which was analysed by headspace and solvent (dichloromethane, DCM) extraction followed by gas chromatography-mass spectrometry (GC-MS). In the second stage, fingerlings (5-20 g) were exposed for 96 hours to the test compound mixture at 1.0 and 0.5 times the estimated tainting threshold concentrations. In the final stage, fingerlings were exposed for 96 hours to an oil sands process water at 5, 10, 20 and 50% concentrations in clean water. None of the test compounds was identified in DCM extracts of tissue from exposed fish. Two long-chain aldehydes, hexadecanal and 9-octadecenal, were tentatively identified in these extracts by matching of mass spectra with library spectra. 相似文献
998.
999.
1000.
We analyze the wear resistance of plasma coatings for a constant work of friction. The dependences of the wear resistance
of the coatings are obtained for a broad range of loading conditions. It is shown that the minimum sensitivity to loading
conditions is exhibited by the molybdenum coatings. It is also established that the wear resistance of the coatings decreases
as the amplitude of displacements increases and the cyclic frequency of the tests decreases due to the intensification of
fatigue processes on the surfaces. The comparative characteristics of coatings are presented.
__________
Translated from Problemy Prochnosti, No. 5, pp. 94–100, September–October, 2007. 相似文献