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991.
TSD studies of PVAc thermoelectrets reveal that the magnitudes of β and α′-peaks increase whereas that of α-peak decreases with the time of X-irradiation. The total residual charge as well as the charge corresponding to the α-peak are found to decrease linearly with the time of X-irradiation. 相似文献
992.
A new method which takes into account the separate matrix correction factors for bulk and surface has been tried out for quantitative
Auger electron spectroscopy analysis of binary alloys. The calculations use an iteration scheme. It has been applied to the
Fe-Cr alloys studied at this Centre and the Auger electron spectroscopy data for the other alloy systems available in literature.
The results are now more compatible with the expectation that the surface composition is different from the bulk. 相似文献
993.
994.
Phase-matched second-harmonic generation in an organic thin film waveguide has been observed for the first time. A polycrystalline thin film of para-chlorophenylurea has been deposited on glass and the refractive index of the film measured at several wavelength between 450 and 880 nm. A TMω0 → TM2ω2 upconversion process has been observed for fundamental wavelength in the vicinity of 0.88 μm. 相似文献
995.
J. E. Sauvageau A. K. Jain J. E. Lukens 《International Journal of Infrared and Millimeter Waves》1987,8(10):1281-1286
Voltage tunable oscillators operating at millimeter and submillimeter wavelengths can be designed and fabricated using series arrays of Josephson junctions. The coherent radiation obtained from such oscillators results from the mutual phase-locking of the junction through the high-frequency Josephson current generated in the array. A 40-junction array of Josephson junctions distributed over many wavelengths has been designed, fabricated and tested for operation at 100 GHz. This paper presents the experimental results obtained for this prototype array. A review of the theory for optimizing array design is presented along the implications for power generation at submillimeter wavelengths in future arrays. 相似文献
996.
Using singular surface theory, the phenomena associated with the uniform and nonuniform propagation of weak discontinuities through thermally conducting and dissociating gases is studied. The basic differential equations governing the criteria for decay or blow up of these discontinuities is obtained. It turns out that growth and decay of weak discontinuities are derived and solved completely. The the thermal conduction and dissociation allow the existence of a singular surface carrying a weak discontinuity which grows into a shock and the role of dissociation and thermal conduction is to cause rapid damping in the formation of this shock. 相似文献
997.
K. L. Ramakumar B. P. Datta V. D. Kavimandan S. K. Aggarwal P. M. Shah V. A. Raman V. L. Sant P. A. Ramasubramanian H. C. Jain 《Fresenius' Journal of Analytical Chemistry》1984,318(1):12-14
Summary Relative Sensitivity Factors (RSFs) for the rare earth elements Ce, Nd, Sm, Eu, Gd, Dy, Er and Lu in U3O8 have been determined by Spark Source Mass Spectrometry (SSMS) using the electrical detection system in peak switching mode. Earlier RSFs for these elements were determined in uranyl nitrate and it was expected that though the absolute value of the RSFs may be different, the trend would be the same. However, the present work shows that apart from the magnitude, the trend in RSF values is also different. The data from the present work are in agreement with the theoretical calculations based on the decomposition energies of the rare earth oxides and support the work carried out by others in the case of Y2O3 matrix.
Relative Empfindlichkeitsfaktoren für die Bestimmung Seltener Erden in Uranoxid mit Hilfe der Funken-Massenspektrometrie
Zusammenfassung Die relativen Empfindlichkeitsfaktoren für die Elemente Ce, Nd, Sm, Eu, Gd, Dy, Er und Lu in U3O8 wurden mit der Funken-Massenspektrometrie mit elektrischem Nachweis (peak switching) bestimmt. Früher sind diese Faktoren in Uranylnitrat bestimmt worden und es wurde erwartet, daß trotz unterschiedlicher absoluter Werte der Trend derselbe wäre. Es zeigte sich jedoch, daß auch der Trend verschieden ist. Die Werte der vorliegenden Untersuchung stimmen mit theoretischen Berechnungen aus den Zersetzungsenergien der Seltenerdoxide überein und bestätigen die Ergebnisse anderer Autoren für die Y2O3-Matrix.相似文献
998.
Potential theory characteristically leads to partial differential equations under boundary conditions. It is shown that these boundary-value problems can be converted directly into equivalent initial-value problems. These initial-value problems are shown to lead to a number of standard and nonstandard numerical procedures.This research was supported by the National Institutes of Health under Grants Nos. GM-16197-01 and GM-16437-01 and by the Atomic Energy Commission under Contract No. AT(11-1)-113, Project No. 19. 相似文献
999.
1000.