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101.
Depending on the spectal width of the source illuminating an interferometer, measurement procedures can utilize either the whole interferogram, or only the fringe envelope, or only the fringe quick oscillations. With an ultraband spectrum source, a simplified adaptation of the methods of Fourier transform spectroscopy yields the variations of the test-fiber propagation constant over the whole wavelength-interval of the source. Chromatic dispersion can then be computed from a single interferogram. With narrower spectrum sources, only the fringe envelopes are utilized and yield measurements of mode delay, with application to chromatic and polarization mode dispersion. In this case, however, interferograms at several wavelengths are necessary. With even narrower spectrum sources, the fringe quick oscillations provide measurements of phase shifts, related to changes in the mode propagation constant, when outside perturbations are applied to the test fiber. A direct method for measuring the third-order nonlinear susceptibilities is discussed. In this case the outside perturbation is an intense pump laser field  相似文献   
102.
The aim of this paper is the comparison of the axial flux (AF) structures versus the conventional radial flux (RF) structures for permanent-magnet synchronous motors. The comparison procedure is based on simple thermal considerations. Two motor typologies are chosen and compared in terms of delivered electromagnetic torque. The comparison is developed for different motor dimensions and the pole number influence is put into evidence. The paper reports the complete comparison procedure and the related results analysis. The obtained results show that, when the axial length is very short and the pole number is high, the AF motors can be an attractive alternative to the conventional RF solutions.  相似文献   
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106.
Incremental transmission loss analysis has been used for decades, but recent interest in its application to loss allocation calls for new in-depth results. This paper demonstrates that, for incremental methods to be applied correctly in loss allocation, it is first necessary to specify the load distribution and loss supply strategies. Incremental loss allocation among bus power injections is shown to be arbitrary and, therefore, open to challenge as discriminatory. Loss allocation is possible among incremental loads and/or generators, but the proportion of the total losses assigned to either one is arbitrary. Unique, nonarbitrary incremental loss allocations are however possible among the "equivalent" incremental bilateral exchanges between generators and loads. From these basic components it is possible then to calculate the allocation among generators or loads in any specified proportion. The main results, although developed initially for small increments, are extended to large variations. Finally, a general incremental loss allocation algorithm is developed and tested  相似文献   
107.
Shevchenko  V. P.  Nagaev  I. Yu.  Myasoedov  N. F. 《Radiochemistry》2002,44(4):380-383
Androstenedione labeled with tritium at positions 1 and 2 was prepared. The molar radioactivity of the sample prepared using homogeneous catalysts was as high as 1.4-1.5 PBq mol- 1. [1,2-3H]Androst-4-ene-3,17-dione can be converted into the [1-3H]steroid with the molar radioactivity of 0.9 PBq mol- 1.  相似文献   
108.
The equal-channel angular extrusion (ECAE) technique has been applied to a powder metallurgy (P/M) source Be alloy. Extrusions have been successfully completed on Ni-canned billets of Be at approximately 425°C. No cracking was observed in the billets, and significant grain refinement was achieved. In this article, microstructural features and dislocation structures are discussed for a singlepass extrusion, including evidence of <c> and <c+a> dislocations. Significant crystallographic texture developed during ECAE, which is discussed in terms of this unique deformation processing technique and the underlying physical processes which sustain the deformation. S.R. AGNEW, formerly with the Oak Ridge National Laboratory, Oak Ridge, TN 37831-6115 This article is based on a presentation made in the symposium entitled “Defect Properties and Mechanical Behavior of HCP Metals and Alloys” at the TMS Annual Meeting, February 11–15, 2001, in New Orleans, Louisiana, under the auspices of the following ASM committees: Materials Science Critical Technology Sector, Structural Materials Division, Electronic, Magnetic & Photonic Materials Division, Chemistry & Physics of Materials Committee, Joint Nuclear Materials Committee, and Titanium Committee.  相似文献   
109.
The article presents the results of experimental investigations of critical (limit) heat fluxes upon evaporation on porous coatings, and it substantiates the physical model of the process.Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 49, No. 4, pp. 607–614, October, 1985.  相似文献   
110.
Using a flow method, we have measured the vapor pressure of tellurium tetraiodide, an attractive reagent for chemical vapor deposition technology. The results, combined with earlier tensimetric data, have been used to evaluate the basic thermodynamic functions of TeI4 and its thermolysis products.  相似文献   
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