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91.
92.
Utarō Furukane Toshiaki Yokota Toshiatsu Oda 《Journal of Quantitative Spectroscopy & Radiative Transfer》1979,22(3):239-245
The collisional-radiative model is applied to a recombining hydrogen plasma in order to investigate plasma conditions in which a population inversion between the energy levels of hydrogen can be generated. Population inversion is expected in plasmas for which three-body recombination makes a large contribution to the recombining processes and the effective recombination rate is larger than a critical value for a given electron density and temperature. Calculated results are presented in figures and tables. 相似文献
93.
94.
Utarō Furukane Yasumasa Tsuji Toshiatsu Oda 《Journal of Quantitative Spectroscopy & Radiative Transfer》1982,27(5):557-562
Plasma conditions for generating a population inversion between the ground and first excited states in a recombining hydrogen plasma have been investigated on the basis of the CR model. Population inversion can be expected when three-body recombination plays a dominant role; the required regions of electron density and temperature are specified. It is shown that upper bounds exist for the ground-state population density at given electron density and temperature. Larger inversion densities can be obtained between the ground and first excited states than between excited levels. Numerical results are presented. 相似文献
95.
96.
Warō Nakanishi Satoru Murata Yoshitsugu Ikeda Tadashi Sugawara Yuzo Kawada Hiizu Iwamura 《Tetrahedron letters》1981,22(42):4241-4244
The reaction of 2-methylselenobenzoic acid with 1,1′-carbonyldiimidazole followed by addition of t-butyl hydroperoxide gave cyclic selenuranes and , suggesting the intramolecular insertion of the neighboring selenium atom into the OO bond of t-butyl 2-methylselenoperoxybenzoate. In the reaction of 2-phenylselenobenzoyl chloride with t-butyl hydroperoxide, cyclic selenurane and the oxide were obtained. 相似文献
97.
98.
Based on straightening the free boundary, a qualocation methodis proposed and analysed for a single phase unidimensional Stefanproblem. This method may be considered as a discrete versionof the H1-Galerkin method in which the discretization is achievedby approximating the integrals by a composite Gauss quadraturerule. Optimal error estimates are derived in L(Wj,), j = 0,1,and L (Hj), j = 0,1,2, norms for a semidiscrete scheme withoutany quasi-uniformity assumption on the finite element mesh. 相似文献
99.
Amiya K. Chakravarty 《The Journal of the Operational Research Society》1985,36(11):1027-1039
The inventory control problem can be vastly simplified if the replenishments of inventory items are coordinated with one another. That is, whenever an item is replenished, n other items, where n is a decision variable, are also replenished. One way to ensure this would be to classify the inventory items into several groups with a common order interval for each group. In this paper we establish that the optimal groups will be consecutive by hD/A, where h, D and A are the holding cost, demand rate and set-up cost of an item respectively. Using this property of consecutiveness, we develop a fast converging heuristic to create m groups optimally, m = 2, 3,..., M. The heuristic is a substitute for the dynamic programme which would otherwise be necessary and it has the potential for nomographic applications. 相似文献
100.
Zenrō Hioki 《Zeitschrift fur Physik C Particles and Fields》1993,59(4):555-561
Λ b semileptonic decay to \(\Lambda _c e\bar v_e \) is studied within the heavy quark effective theory, whereΛ b is moving and polarized along the direction of its motion. Normalized energy distributions ofe andΛ c are both calculated forV±A interactions by taking the corrections and electronp t cut effects into account. It is shown that the form factor (Isgur-Wise function) effects are significant: The shapes of the distribution curves are thereby considerably changed in comparison with those calculated within the quark model. In case of the electron energy spectrums, the difference between theV±A interactions are enhanced, while that in theΛ c energy spectrums decreases. On the other hand, the corrections are found to be negligible in both spectrums. 相似文献