09-06-2010 | Zhibin Du, Bo Zhou, Nenad Trinajstić, Journal of Mathematical Chemistry, 2010

The general sum-connectivity index of a graph G is defined as χ α (G) = ∑edges (d u + d v )α , where d u denotes the degree of vertex u in G and α is a real number. In this report, we determine the minimum and the second minimum values of the general sum-connectivity indices of n-vertex ...

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09-06-2010 | P. L. Dammig Quiña, V. E. Pastor, I. M. Irurzun, E. E. Mola, Journal of Mathematical Chemistry, 2010

The purpose of this paper is to provide an exact evaluation of the configurational degeneracy when an arbitrary number (k) of dipoles are placed in a quasi-two-dimensional space (Q2D). This Q2D is made up of three contiguous diagonals 3 × N. Our Q2D space gives to the central sites of the ...

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09-06-2010 | Bo Zhou, Nenad Trinajstić, Journal of Mathematical Chemistry, 2010

Miličević, Nikolić and Trinajstić (Mol Divers 8:393–399, 2004) proposed the reformed Zagreb indices in 2004. Now we give some properties for the reformed Zagreb indices.

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01-06-2010 | Luca M. Ghiringhelli, Luigi Delle Site, Ricardo A. Mosna, I. P. Hamilton, Journal of Mathematical Chemistry, 2010

We strengthen the connection between information theory and quantum mechanical systems using a recently developed dequantization procedure which results in a decomposition of the kinetic energy as the sum of a classical term and a purely quantum term. For the nearly uniform electron gas, we ...

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25-05-2010 | J. Masiá-Pérez, J. Escribano, E. Valero, E. Arribas, M. García-Moreno, J. L. Muñoz-Muñoz, R. Gómez-Ladrón de Guevara ..., Journal of Mathematical Chemistry, 2010

The kinetic study carried out in paper I of this series (preceding article) on enzyme systems involving zymogen activation and the simultaneous action of two different, mutually exclusive inhibitors (Scheme 1) allows, new dimensionless kinetic parameters to be suggested. These parameters ...

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25-05-2010 | J. Masiá-Pérez, J. Escribano, E. Valero, E. Arribas, M. García-Moreno, J. L. Muñoz-Muñoz, R. Gómez-Ladrón de Guevara ..., Journal of Mathematical Chemistry, 2010

In this paper, a general mechanism of zymogen activation and the simultaneous action of two different, mutually exclusive, two-step inhibitors acting on both the activating and the activated enzymes is proposed and kinetically analyzed. This generalization offers the advantage of being ...

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20-05-2010 | Wenjie Qin, Zhijun Liu, Journal of Mathematical Chemistry, 2010

The main purpose of this paper is to study a general delay difference system of the growth of two species of plankton having competing and allelopathic effects on each other. We first show that the system is permanent under some suitable assumptions. Next, by using the continuous theorem of ...

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15-05-2010 | M. B. A. Mansour, Journal of Mathematical Chemistry, 2010

In this paper we study a reaction–diffusion model equation with general nonlinear diffusion and arbitrary kinetic orders in the reaction terms, which appears in the applied biochemical modeling. We carry both analytical and numerical studies of the model equation to show the existence of ...

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13-05-2010 | Hassan Safouhi, Journal of Mathematical Chemistry, 2010

Of the nuclear magnetic resonance (MMR), the nuclear shielding tensor is of a great interest. The relativistic calculation of the nuclear shielding tensor involves extremely challenging integrals of first and second order. Among the first order integrals are paramagnetic contribution ...

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13-05-2010 | G. Milani, F. Milani, Journal of Mathematical Chemistry, 2010

Sulphur was the first agent used to vulcanize commercial elastomers (e.g. natural rubber) and allows meaningful cost reductions during the industrial process (production cost ratio between peroxides and accelerated sulphur is around 5). Therefore, accelerated sulphur vulcanization is the most ...

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