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991.
The problem of turbulent free convection heat transfer from curved surfaces to non-Newtonian power-law fluids has been investigated using the Nakayama-Koyama solution methodology. The scheme is designed to deal with bodies of arbitrary geometric configurations and hence can be viewed as a generalized version of the Shenoy-Mashelkar approach for turbulent free convection heat transfer from a flat vertical plate to a power-law fluid. The surface wall temperature is allowed to vary in the streamwise direction in an arbitrary fashion, and calculations are carried out for the turbulent free convection about the horizontal circular cylinder and sphere for illustrative purposes. Available theoretical and experimental data have been compared with the predictions of the present analysis and the comparison of results has been found to be reasonably good. 相似文献
992.
Structural changes in cristobalite and silica glass and melt are investigated at high temperatures by molecular dynamics simulations. The calculated interaction energies are analyzed employing a new method called ‘atomistic energy distribution analysis’. Each pair-interaction energy is divided into equal halves which are allocated to each atom. Therefore, each atom has the summed-up value (‘atomistic potential energy’) of half the pair-interaction energies. First, an analysis of atomistic energy distribution functions show a correspondence with structural changes such as α–β phase transition, cristobalite melting and glass transition of SiO2, in harmony with the results obtained in our preceding study. Moreover, this study demonstrates the different roles of oxygen and silicon in terms of structural changes. Finally, newly defined order parameters offer the possibility of distinguishing structures resulting from different thermal histories through introduction of higher moments. 相似文献
993.
994.
Akira Aiba 《Journal of Number Theory》2003,102(1):118-124
Let k be the power series field over a finite field of characteristic p>0. Let L be a cyclic extension over k of degree p. We give a necessary and sufficient condition for the integer ring OL to be free over the associated order. Moreover, when OL is free, we construct a free basis explicitly. 相似文献
995.
Valery I. Chani Akira Yoshikawa Hiroshi Machida Tadakumi Satoh Tsuguo Fukuda 《Journal of Crystal Growth》2000,210(4):663-669
A micro-pulling-down process, using Ir crucibles and RF heating, has been used to grow single-crystal fiber and bulk crystals of Tb3Ga5O12 garnet (TGG). Single crystals ranging up to 450 mm in length have been produced. The crystals were 1–4 mm in diameter and were seeded-grown in the direction close to 1 1 1. The maximal crystal diameter achieved was 10 mm. Dependence of behavior of the solid–liquid interface on the growth parameters (temperature and pulling-rate) is discussed in detail. 相似文献
996.
Kei Kamada Takayuki Yanagida Jan Pejchal Martin Nikl Takanori Endo Kousuke Tsutumi Yoshiyuki Usuki Yutaka Fujimoto Akihiro Fukabori Akira Yoshikawa 《Journal of Crystal Growth》2012,352(1):84-87
Pr:Gd3(Ga,Al)5O12 single crystals were grown by the micro-pulling down (μ-PD) method. All grown crystals were greenish and transparent with 3.0 mm in diameter, 15–30 mm in length. Neither visible inclusions nor cracks were observed. Luminescence and scintillation properties were measured. The substitution at the Al3+ sites by Ga3+ in garnet structure has been studied. In these crystals, Pr3+ 5d–4f emission is observed with 340 nm wavelength. Pr1%:Gd3Ga3Al2O12 shows highest emission intensity. The light yield of Pr:Gd3Ga3Al2O12 sample with 3 mmφ×1 mm size was around 4500 photon/MeV. Scintillation decay time was 7.9 ns (0.5%), 46 ns (0.7%) and 214 ns (98.8%). 相似文献
997.
The iodotrimethylsilane-catalyzed reaction of silyl enol ethers with aminomethyl ethers in acetonitrile gives aminomethylation products of the corresponding ketones readily. The reaction can slso be catalyzed by trimethylsilyl trifluoromethanesulfonate in dichloromethane. 相似文献
998.
A study by computer simulation is reported of the behavior of a quantized vortex line at a very low temperature when there is continuous excitation of low-frequency Kelvin waves. There is no dissipation except by phonon radiation at a very high frequency. It is shown that nonlinear coupling leads to a net flow of energy to higher wave numbers and to the development of a simple spectrum of Kelvin waves that is insensitive to the strength and frequency of the exciting drive. The results are likely to be relevant to the decay of turbulence in superfluid 4He at very low temperatures. 相似文献
999.
In this note we show that in a certain subfamily of the Kuranishi family of any half Inoue surface the algebraic dimensions of the fibers jump downwards at special points of the parameter space showing that the upper semicontinuity of algebraic dimensions in any sense does not hold in general for families of compact non-Kähler manifolds. In the Kähler case, the upper semicontinuity always holds true in a certain weak sense. 相似文献
1000.