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991.
992.
The range of applicability of the mean spherical approximation to a primitive-model electrolyte is extended to allow for stronger Coulomb coupling. The new terms in the approximation are extracted from the HNC formalism, which is adequate for strongly coupled Coulomb systems. The new approximation satisfies the Stillinger-Lovett conditions. The new integral equation thus obtained is presented. 相似文献
993.
W.H Schreiner D.E Brandão F Ogiba J.V Kunzler 《Journal of Physics and Chemistry of Solids》1982,43(8):777-780
The electrical resistivity of eight different Heusler alloys is discussed in terms of electron phonon and spin-disorder scattering. The systematics common to the alloys can be explained in the intermediate to high temperature range while the low temperature range still presents interpretation difficulties. 相似文献
994.
In a slightly acidic medium (sodium acetate-acetic acid buffer, pH 4) saccharin and Nile Blue form an ion-association compound which is extractable into methyl isobutyl ketone and allows the spectrophotometric determination of saccharin. At 630 nm Beer's law is obeyed over the saccharin concentration range 0.1-3.5 microg/ml in the aqueous phase and the apparent molar absorptivity is 5.8 x 10(4) l.mole(-1).cm(-1). The method shows good selectivity and can be applied to the determination of saccharin in artificial sweeteners, soft drinks and toothpastes. 相似文献
995.
996.
J. Sebastião e Silva 《Mathematische Annalen》1967,174(2):109-142
Sans résuméÀ MonsieurGottfried Köthe, à l'occasion de son 60me anniversaire 相似文献
997.
J.M. Alvariño María Luz Hernández L. Lain M. de Renobales Alicia Torre 《European Polymer Journal》1978,14(12):991-994
The effect of the gravimetric ratio, packing beads/polymer (r), in the chromatographic fractionation of polystyrene has been studied. Anionic polystyrene of bimodal molecular weight distribution was fractionated in three experiments with r values of 25, 50 and 130; a value of about 50 provided the most efficient separation. A GPC self-consistency analysis of this fractionation has been done with very satisfactory results. On the other hand, GPC analysis could not show any significant broadening of the molecular weight distributions of the fractions in going from r values of 130 down to 25. 相似文献
998.
In classical studies of loss systems with restricted availability, the utilization was suggested of a probabilistic loss function, defining the conditional probability of an incoming call being rejected, as a function of the number of occupations in the destination group of servers. This paper gives an exact analysis of stochastic processes of practical relevance, associated with a system with MMPP (Markov Modulated Poisson Process) input, finite queueing capacity and a general loss function, assuming exponential service times. In addition to the process defining the state of the system at any instant, the analysis of the overflow point process (associated with the rejected arriving customers), the accepted point process (associated with the accepted arriving customers), and of the departure process will be presented. Together with the exact analysis of this system, based on the matrix analytical methodology of Neuts, (1981), we will derive expressions for calculating some key-parameters of pertinent associated processes, which may also be used for their approximate modelling. Also, examples of applications and of blocking probability calculations in specific models of this class will be presented. 相似文献
999.
Ja?o B. Prolla 《Rendiconti del Circolo Matematico di Palermo》1993,42(1):93-105
IfS is a compact Hausdorff space of finite covering dimension and (E, τ) is a real or complex topological vector space (not necessarily locally convex), we prove a Weierstrass-Stone theorem
for subsets ofC(S;E), the space of all continuous functions fromS intoE, equipped with the topology of uniform convergence overS. 相似文献
1000.
A class of Bianchi IX cosmological models is shown to have chaotic gravitational collapse, due to Poincaré's homoclinic phenomena. We can program such models so that for any given positive integer N (N=∞ included) the universe undergoes N non-periodic oscillations (each oscillation requiring a long time) before collapsing. For N=∞ the universe undergoes periodic oscillations. 相似文献