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91.
García Calzón JA Muñiz Alvarez JL López Fonseca JM 《Journal of colloid and interface science》2005,290(2):498-504
The oxidation process induced by 2-mercaptopyrimidine (RSH) at a hanging mercury drop electrode was studied in aqueous media by normal and cyclic voltammetry. The results indicate the formation of a weakly adsorbed HgSR complex according to the reaction Hg+RSH-->HgSR+e(-)+H+. When the surface excess of HgSR is high, a two-dimensional condensation takes place if the potential is positive enough, as proved by phase-sensitive ac and cyclic voltammetry. 相似文献
92.
Luís Felipe Gonçalves Fonseca 《代数通讯》2018,46(4):1630-1640
Let F be an infinite field and let Mn(F) be the algebra of n×n matrices over F endowed with an elementary grading whose neutral component coincides with the main diagonal. In this paper, we find a basis for the graded polynomial identities of Mn(F) with the transpose involution. Our results generalize for infinite fields of arbitrary characteristic previous results in the literature, which were obtained for the field of complex numbers and for a particular class of elementary G-gradings. 相似文献
93.
M. Conceição Fonseca Álvaro García-Sánchez Miguel Ortega-Mier Francisco Saldanha-da-Gama 《TOP》2010,18(1):158-184
In this paper we propose a comprehensive model for reverse logistics planning where many real-world features are considered
such as the existence of several facility echelons, multiple commodities, choice of technology and stochasticity associated
with transportation costs and waste generation. Moreover, we adopt a bi-objective model for the problem. First, the cost for
building and operating the network is to be minimized. Second, the obnoxious effect caused by the reverse network facilities
is also to be minimized. A two-stage stochastic bi-objective mixed-integer programming formulation is proposed, in which the
strategic decisions are considered in the first stage and the tactical/operational decisions in the second one. A set of different
scenarios is considered, and the extensive form of the deterministic equivalent problem is presented. This model is tested
with a case study based on some data from the Spanish province of Cordoba. Nondominated solutions are obtained by combining
the two different objectives and by using a general solver. 相似文献
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Annibal Figueiredo Marcio T. de Castro Regina C.B. da Fonseca Iram Gleria 《Physics letters. A》2013,377(25-27):1571-1581
We investigate which type of diffusion equation is most appropriate to describe the time evolution of foreign exchange rates. We modify the geometric diffusion model assuming a non-exponential time evolution and the stochastic term is the sum of a Wiener noise and a jump process. We find the resulting diffusion equation to obey the Kramers–Moyal equation. Analytical solutions are obtained using the characteristic function formalism and compared with empirical data. The analysis focus on the first four central moments considering the returns of foreign exchange rate. It is shown that the proposed model offers a good improvement over the classical geometric diffusion model. 相似文献
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In this article, we are interested in the enumeration of Fully Packed Loop configurations on a grid with a given noncrossing matching. These quantities also appear as the groundstate components of the O(n) Loop model as conjectured by Razumov and Stroganov and recently proved by Cantini and Sportiello. 相似文献