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981.
Une nouvelle enceinte destinée à la production de l,or colloïdal radioactif198Au à usage thérapeutique et diagnostique est construite dans le Laboratoire de Chimie de Haute Activité à l'Institut des Sciences Nucléaires ?Boris Kidri?”. L'enceinte comporte deux appareils pour la préparation des colloïdes de l'or radioactif, permettant une production permanente méme au cas où l'un des appareils est accidenté. C'est grâce à une conception originale de la protection en plomb que l'accès aus appareils et aux stocks des effluents est rendu facile et ainsi que les systèmes de commande des processus des processus chimiques et la manipulation dans l,enceinte sont bien simplifiés 相似文献
982.
R. S. Drašković J. Bzenić M. Ratković R. J. Drašković 《Isotopes in environmental and health studies》2013,49(8):290-293
Stability of radioactive sodium ortho-131I-hippurate produced at the Boris Kidri? Institute, Vin?a, according to the modified procedure for application in nuclear medicine in Yugoslavia was investigated. In these investigations stability was observed as a function of the ageing time of the solutions, their radioactivity (A mCi/ml; A mCi/mg of the carrier; Atot), the presence of some bacteriostatics and stabilizers (C6H5—CH2OH, Na-citrate), sterilization process and storage conditions. 相似文献
983.
The aim of this paper is to show that the procedure of maximum entropy principle for the closure of the moments equations for rarefied monatomic gases can be extended also to polyatomic gases. The main difference with respect to the usual procedure is the existence of two hierarchies of macroscopic equations for moments of suitable distribution function, in which the internal energy of a molecule is taken into account. The field equations for 14 moments of the distribution function, which include dynamic pressure, are derived. The entropy and the entropy flux are shown to be a generalization of the ones for classical Grad’s distribution. The results are in perfect agreement with the recent macroscopic approach of extended thermodynamics for real gases. 相似文献
984.
The widespread use of gas discharge tubes (GDTs) and avalanche diodes for transient voltage suppression (TVS) in many cases results in their exposure to ionizing radiation. The aim of this paper is to investigate the influence of irradiation on these TVS devices’ characteristics, by exposing them to a combined neutron/gamma radiation field. Experimental results show that irradiation of TVS diodes causes a lasting degradation of their protective characteristics. On the other hand, GDTs exhibit a temporary change of performance. The observed effects are presented with the accompanying theoretical interpretations, based on the interaction of radiation with materials constituting the investigated devices. 相似文献
985.
Sanja Marušić 《Applicable analysis》2013,92(3-4):379-401
Using the homogenization theory, we derive the nonlinear Reynolds equation governing the process of lubrication of a slipper bearing with rapidly rotating shaft. We prove that this nonliner lubrication law is an approximation of the full Navier-Stokes equations in a thin cylinder with periodic roughness. The analyticity of the nonlinear function giving the relation between the velocity and the pressure drop is proved. The first term in its Taylor's expansion is the classical linear Reynolds law. Boundary layer correctors are computed. 相似文献
986.
Goran Djanković 《Czechoslovak Mathematical Journal》2013,63(3):833-845
Classical Kloosterman sums have a prominent role in the study of automorphic forms on GL2 and further they have numerous applications in analytic number theory. In recent years, various problems in analytic theory of automorphic forms on GL3 have been considered, in which analogous GL3-Kloosterman sums (related to the corresponding Bruhat decomposition) appear. In this note we investigate the first four power-moments of the Kloosterman sums associated with the group SL3(?). We give formulas for the first three moments and a nontrivial bound for the fourth. 相似文献
987.
Milica Anđelić Domingos M. Cardoso Slobodan K. Simić 《Czechoslovak Mathematical Journal》2013,63(1):73-90
Let G be a finite graph with an eigenvalue µ of multiplicity m. A set X of m vertices in G is called a star set for µ in G if µ is not an eigenvalue of the star complement G\X which is the subgraph of G induced by vertices not in X. A vertex subset of a graph is (κ, τ)-regular if it induces a κ-regular subgraph and every vertex not in the subset has τ neighbors in it. We investigate the graphs having a (κ, τ)-regular set which induces a star complement for some eigenvalue. A survey of known results is provided and new properties for these graphs are deduced. Several particular graphs where these properties stand out are presented as examples. 相似文献
988.
989.
Let $f$ be a real entire function whose set $S(f)$ of singular values is real and bounded. We show that, if $f$ satisfies a certain function-theoretic condition (the “sector condition”), then $f$ has no wandering domains. Our result includes all maps of the form $z\mapsto \lambda \frac{\sinh (z)}{z} + a$ with $\lambda >0$ and $a\in \mathbb{R }$ . We also show the absence of wandering domains for certain non-real entire functions for which $S(f)$ is bounded and $f^n|_{S(f)}\rightarrow \infty $ uniformly. As a special case of our theorem, we give a short, elementary and non-technical proof that the Julia set of the exponential map $f(z)=e^z$ is the entire complex plane. Furthermore, we apply similar methods to extend a result of Bergweiler, concerning Baker domains of entire functions and their relation to the postsingular set, to the case of meromorphic functions. 相似文献
990.
Let G n be the set of all real algebraic polynomials of degree at most n, positive on the interval (?1, 1) and without zeros inside the unit circle (|z| < 1). In this paper an inequality for the polynomials from the set G n is obtained. In one special case this inequality is reduced to the inequality given by B. Sendov [5] and in another special case it is reduced to an inequality between uniform norm and norm in the L 2 space for the Jacobi weight. 相似文献