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721.
In the ternary system Ce2O3-K2O-P2O5, the partial system Ce(PO3)3-KPO3-P2O5 was examined by means of differential thermal analysis and powder X-ray diffraction. The phase compositions of the products obtained on various thermal treatments were investigated. The phase diagram of the system Ce(PO3)3-KPO3-P2O5 is suggested.
Zusammenfassung Mittels DTA und Röntgendiffraktion wurde im ternären System Ce2O3-K2O-P2O5 das Teilsystem Ce(PO3)3-KPO3-P2O5 untersucht. Die Phasenzusammensetzungen der durch verschiedene Erhitzungsvorgänge erhaltenen Produkte wurden untersucht und ein Phasendiagramm für das System Ce(PO3)3-KPO3-P2O5 erstellt.相似文献
722.
Mutual precipitates of poly (N, N-dimethyl acrylamide) and poly (4-hydroxystyrene) were collected from dioxane, methanol, or acetone. The glass transition (Tg) temperatures of the precipitates are higher than the weight-average values. Clear films cast from dimethylformamide solutions have lower Tg values. Complexation also occurred between poly (ethyl oxazoline) and poly (4-hydroxystyrene) in dioxane and between poly (vinyl pyrrolidone) and poly (4-hydroxystyrene) in methanol. Again, the glass transition temperatures of the precipitates are higher than the values for the blend films. The ΔCp values associated with the glass transitions of the complexes are smaller than those of the blends having the same compositions. Negative excess heat capacities of mixing have been observed for several precipitates. 相似文献
723.
K. Ishikawa H. Nakano H. Masuda C. Kusano Y. Takahashi T. Hamagishi N. Endo 《Fiber and Integrated Optics》1992,11(4):385-394
A 10-Gbit/s optical receiver is developed using low-capacitance HBT IC technology. The HBT allows a cutoff frequency of 45 GHz and a maximum oscillation frequency of 70 GHz. The receiver contains an automatic gain-control amplifier IC with a gain of 16 dB, a bandwidth of 10.7 GHz, and a decision-circuit IC with an ambiguity of 66 mVp-p at a data rate of 10 Gbit/s. The sensitivity of this receiver is -26.5 dBm at a bit error rate of 10-9. Transmission over a 140-km fiber was achieved successfully. 相似文献
724.
Muonium in liquid SiCl has been observed for the first time at low temperature (−65°C) The observed polarization of muonium
is as much as 25% of the total spin polarization and shows a fast relaxation rate. 相似文献
725.
L. S. de C. Oliveira M. T. X. Silva A. Vasquez J. A. H. da Jornada 《Hyperfine Interactions》1991,66(1-4):267-270
An exploratory Mössbauer spectroscopy study of the Fe-C system in the C rich region, prepared by high pressure-high temperature treatment near the graphite-diamond stability line, was made. The results obtained for the different processing conditions give no evidence of Fe intercalation in graphite. The presence of some water in the cell produced hydrated Fe complexes, which can explain the deleterious effect of water or hydrogen in the high pressure diamond synthesis. 相似文献
726.
Unsteady flow dynamics in doubly constricted 3D vessels have been investigated under pulsatile flow conditions for a full cycle of period T. The coupled non‐linear partial differential equations governing the mass and momentum of a viscous incompressible fluid has been numerically analyzed by a time accurate Finite Volume Scheme in an implicit Euler time marching setting. Roe's flux difference splitting of non‐linear terms and the pseudo‐compressibility technique employed in the current numerical scheme makes it robust both in space and time. Computational experiments are carried out to assess the influence of Reynolds' number and the spacing between two mild constrictions on the pressure drop across the constrictions. The study reveals that the pressure drop across a series of mild constrictions can get physiologically critical and is also found to be sensitive both to the spacing between the constrictions and the oscillatory nature of the inflow profile. The flow separation zone on the downstream constriction is seen to detach from the diverging wall of the constriction leading to vortex shedding with 3D features earlier than that on the wall in the spacing between the two constrictions. Copyright © 2002 John Wiley & Sons, Ltd. 相似文献
727.
V. A. Donchenko M. V. Kabanov V. T. Kalaida B. I. Kulakov E. V. Ovcharenko I. G. Sokovets 《Russian Physics Journal》1998,41(5):476-484
The problems of determining and investigating the informative parameters of atmospheric electricity are discussed. It is shown
that short-period variations in atmospheric electricity are ecologically significant. An automated system for monitoring atmospheric
electricity and a method of processing the results of measurements are described.
V. D. Kuznetsov Siberian Physicotechnical Institute, Tomsk State University. Translated from Izvestiya Vysshikh Uchebnykh
Zavedenii, Fizika, No. 5, pp. 88–98, May, 1998. 相似文献
728.
It is predicted that resonance coupling between two discrete electron energy levels corresponding to different size-quantization
quantum numbers and different Landau quantum numbers can occur in a quantum well in a quantizing magnetic field. The resonance
coupling is due to the interaction of an electron with LO phonons and results in the formation of polaron states of a new type. It is shown that for a certain value of the magnetic
field, which depends on the splitting of the electron size-quantization levels, the absorption peak and the two-phonon resonance
Raman scattering peak split into two components, the separation between which is determined by the electron-phonon coupling
constant. The resonance coupling between size-quantization levels with the same Landau quantum numbers is also studied. The
splitting of the peaks in this case is virtually independent of the magnetic field and can be observed in much weaker fields.
The experimental observation of the effect will make it possible to determine the relative position of the electronic levels
and the electron-phonon coupling constant.
Pis’ma Zh. éksp. Teor. Fiz. 65, No. 7, 511–515 (10 April 1997) 相似文献
729.
T. A. Berger 《Journal of separation science》1989,12(2):96-100
A model for restrictor flow produces accurate predictions of flow that can be used to optimize restrictor design. The relative amplitudes of restrictor and other flows and their effect on efficiency are discussed. 相似文献
730.
We have investigated the structure of spider dragline silk by X-ray diffraction over a broad temperature range from room temperature
up to thermal denaturation conditions. The dominating signal from the β-sheet crystallites is analyzed. Pronounced changes
of scattering intensity starting at temperatures around 150 °C are observed. These changes are discussed in view of the respective
lattice constants, crystal size, size distribution, crystallite number density and amino acid composition.
PACS 87.68.+z; 87.15.-v; 87.64.Bx 相似文献