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11.
M. C. Fornaciari Iljadica J. C. Furnari I. M. Cohen 《Journal of Radioanalytical and Nuclear Chemistry》2006,270(1):273-275
Summary The evolution of education in Argentina at the university level is described. The detailed search of the educational offer
shows that less than half of the universities (35 out of 92) include chemistry and chemistry related undergraduate programmes
in their curriculum. The revision of the position of radiochemistry in these programmes reveals that only seven courses on
radiochemistry are currently offered. Radiochemistry is included only in few programmes in chemistry and biochemistry. With
respect to the programmes in chemical engineering the situation is worse. This offer is strongly concentrated in Buenos Aires
and its surroundings. 相似文献
12.
Let X be a locally self-similar stochastic process of index 0<H<1 whose sample paths are a.s. CH?ε for all ε>0. Then the Hausdorff dimension of the graph of X is a.s. 2?H. To cite this article: A. Benassi et al., C. R. Acad. Sci. Paris, Ser. I 336 (2003). 相似文献
13.
The reaction of CH3 with OH has been studied near 1200 K and 1 atmosphere pressure in shock tube experiments in which UV absorption was used to monitor [OH]. A rate coefficient of (1.1 ± 0.3) × 1013 cm3/mol-s was measured for removal of OH by CH3. This measured value is compared with previous experimental data and calculations. Several possible reaction channels are discussed, and although products were not monitored, it seems probable, on the basis of other work and theoretical estimates, that the primary mechanism (?75%) for the removal of OH by CH3 at these conditions is their combination to form CH3OH. Rate coefficients of (5.3 ± 0.8) × 1012 and (9.0 ± 1.4) × 1012 cm3/mol-s were measured for the reactions of OH with acetone and ethane, respectively, at the same temperature and pressure. 相似文献
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An asymptotic formula is obtained for the number of representations of an element of a finite field as a weighted sum of two prescribed powers of primitive elements. This generalises previous work on sums of primitive elements, including that relating to some conjectures of Golomb. 相似文献
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Albert Cohen Sidi Mahmoud Kaber Siegfried Mü ller Marie Postel. 《Mathematics of Computation》2003,72(241):183-225
The use of multiresolution decompositions in the context of finite volume schemes for conservation laws was first proposed by A. Harten for the purpose of accelerating the evaluation of numerical fluxes through an adaptive computation. In this approach the solution is still represented at each time step on the finest grid, resulting in an inherent limitation of the potential gain in memory space and computational time. The present paper is concerned with the development and the numerical analysis of fully adaptive multiresolution schemes, in which the solution is represented and computed in a dynamically evolved adaptive grid. A crucial problem is then the accurate computation of the flux without the full knowledge of fine grid cell averages. Several solutions to this problem are proposed, analyzed, and compared in terms of accuracy and complexity.
20.
M. A. Cohen Stuart G. J. Fleer B. H. Bijsterbosch 《Journal of colloid and interface science》1982,90(2)
The adsorption of the flexible, linear, and nonionic homopolymer poly(vinyl pyrrolidone) from water and from 1,4-dioxane onto pyrogenic silica was studied. Results are reported for the adsorbed amount as a function of adsorption time, molecular mass, and molecular mass distribution (polydispersity). It is found that the adsorption of fractionated samples can be qualitatively explained by the recent theory of Scheutjens and Fleer. However, the influence of the solvent type is larger than predicted by this theory, and an extension of the model to account for this influence is suggested. The polydispersity effects encountered in adsorption isotherms are satisfactorily accounted for by a theory published by Cohen Stuart, Scheutjens, and Fleer. 相似文献