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991.
We report on the synthesis results obtained for some compositions in the Co(GaxIn1-x)2S4 family, whose intermediate member CoGaInS4 is shown to display a layered structure. This result is discussed and compared with the literature. 相似文献
992.
Measurement Techniques - 相似文献
993.
Acoustic emission technique for leak detection in an end shield of a pressurised heavy water reactor
P. Kalyanasundaram T. Jayakumar B. Raj C.R.L. Murthy A. Krishnan 《Nuclear Engineering and Design》1989,116(2)
This paper discusses the successful application of the Acoustic Emission Technique (AET) for detection and location of leak paths present on the inaccessible side of an end shield of a Pressurised Heavy Water Reactor (PHWR). The methodology was based on the fact that air and water leak AE signals have different characteristic features. Baseline data was generated from a sound end-shield of a PHWR for characterizing the background noise. A mock up end-shield system with saw cut leak paths was used to verify the validity of the methodology. It was found that air leak signals under pressurisation (as low as 3 psi) could be detected by frequency domain analysis. Signals due to air leaks from various locations of a defective end-shield were acquired and analysed. It was possible to detect and locate leak paths. Presence of detected leak paths were further confirmed by alternate test. 相似文献
994.
995.
Numerical solution of the inverse problem of heat conduction by using regularized difference schemes
P. N. Vabishchevich 《Journal of Engineering Physics and Thermophysics》1985,49(6):1446-1449
The stability of difference schemes is investigated for the approximate solution of a multidimensional incorrect heat-conduction problem with inverse time.Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 49, No. 6, pp. 963–965, December, 1985. 相似文献
996.
The growth kinetics, crystal structure, and morphology of the intermetallic compounds formed between nickel, electroless Ni-P and electroless Ni-B coatings with tin at 453 to 493 K for times up to 506 h have been determined by microscopical and X-ray diffraction techniques. The compound Ni3Sn4 was formed. All kinetics followed as parabolic law with activation energies of 128.0, 130.4, and 122.3 kJ mol–1 for the Ni/Sn, Ni-P/Sn and Ni-B/Sn systems, respectively. The rate of growth of Ni3Sn4 in the Ni/Sn and Ni-P/Sn systems were similar but the rate of growth in the Ni-B/Sn system was five times faster. Pores occurred in the intermetallic compound formed in the Ni-P/Sn system and these are discussed in relation to the density of the phases. 相似文献
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