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91.
A. Das D. Mukhopadhyay S. Adhikari M. Baer 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2011,65(3):373-381
In this article are presented the first ever derived single-valued
diabatic potentials for the reactive H2 + F system based on a
rigorous study of the conical intersection (ci) and
Born-Oppenheimer non-adiabatic coupling terms (BO NACTs). This study revealed the
existence of a Jahn-Teller (1, 2) ci located at a point on the collinear
axis and a Renner-Teller (2, 3) ci along this axis. The diabatic
potentials were calculated employing the rigorous adiabatic-to-diabatic transformation
(ADT) angles (also known as mixing angles) which possess integer Berry
phases along any closed contour at the region of interest in configuration space. The ADT
angles were calculated employing BO NACTs and line integrals. 相似文献
92.
Sharma VK Mitra S Kumar A Yusuf SM Juranyi F Mukhopadhyay R 《J Phys Condens Matter》2011,23(44):446002
Here we report the dynamical behaviour of water in Prussian blue analogue (PBA) Cu(0.75)Mn(0.75)[Fe(CN)(6)]·7H(2)O molecular magnet in the temperature range 260-360 K as studied using the quasielastic neutron scattering technique. While significant quasielastic broadening is observed in the hydrated sample, no broadening was observed in the dehydrated one. Data analysis showed that the observed quasielastic broadening in Cu(0.75)Mn(0.75)[Fe(CN)(6)]·7H(2)O corresponds to the dynamics of the non-coordinated water molecules at the 32f site and the coordinated water molecules at the 24e site, existing in the cavities created by the absence of Fe(CN)(6) units. The non-coordinated water molecules at 8c interstitial sites do not contribute to the broadening, suggesting that they are immobile at least within the time window of the spectrometer used. Behaviour of the elastic incoherent structure factor is consistent with the model where the water molecules undergo translational diffusion localized within the cavity of 5.1 ?. While all the non-coordinated water molecules at the 32f site are dynamic over the entire range of temperatures, the coordinated ones at the 24e site become progressively dynamic with temperature. The water molecules were found to undergo hindered (~1.16 × 10(-5) cm(2) s(-1) at 300 K) diffusion compared to bulk water and the diffusivity followed Arrhenius behaviour within the measured temperature range with an activation energy of 1.26 kcal mol(-1). 相似文献
93.
Partha Mukhopadhyay 《Annales Henri Poincare》2014,15(5):937-963
We rewrite the bosonic worldsheet theory in curved background in a language where it describes a single particle moving in an infinite-dimensional curved spacetime. This language is developed at a formal level without regularizing the infinite-dimensional traces. Then, we adopt DeWitt’s (Phys Rev 85:653, 1952) coordinate-independent formulation of quantum mechanics in the present context. This procedure enables us to define coordinate invariant quantum analogue of classical Virasoro generators, which we call DeWitt–Virasoro generators. This framework also enables us to calculate the invariant matrix elements of an arbitrary operator constructed out of the DeWitt–Virasoro generators between two arbitrary scalar states. Using these tools, we further calculate the DeWitt–Virasoro algebra in spin-zero representation. The result is given by the Witt algebra with additional anomalous terms that vanish for Ricci-flat backgrounds. Further analysis need to be performed to precisely relate this with the beta function computation of Friedan and others. Finally, we explain how this analysis improves the understanding of showing conformal invariance for certain pp-wave that has been recently discussed using hamiltonian framework. 相似文献
94.
Different all-optical logic operations, memory blocks etc. are developed using the inherent parallelism of optics. In any digital communication and computation system, the role of serial to parallel and parallel to serial data conversion are very much essential for making a data convenient for transition.Here in this paper, the authors propose a new scheme for developing an all-optical parallel to serial data conversion system by using optical J-K Flip-Flops and some logic gates based on optical non-linear switches. The uses of such switches are widely established in the area of optical parallel computation.This process can be extend for developing some all-optical digital devices like shift register, optical pulse counters etc. The proposed scheme deals with the best use of high parallelism of the optics, so the super-fast processing speed can be achieved. 相似文献
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97.
Mrinal Kanti Roychowdhury 《Journal of Mathematical Analysis and Applications》2011,383(2):499-505
The quantization dimension function for a probability measure induced by a set of infinite contractive similarity mappings and a given probability vector is determined. A relationship between the quantization dimension function and the temperature function of the thermodynamic formalism arising in multifractal analysis is established. The result in this paper is an infinite extension of Graf and Luschgy [S. Graf, H. Luschgy, The quantization dimension of self-similar probabilities, Math. Nachr. 241 (2002) 103-109]. 相似文献
98.
Goutam Mukhopadhyay Jasmina Khanam Arunabha Nanda Arindam Basu Sarkar 《Chromatographia》2010,71(7-8):699-702
A simple, sensitive and precise reverse phase liquid chromatographic method has been developed and validated for quantification of bovine serum albumin (BSA), α-lactalbumin (α-La) and β–lactoglobulin (β-Lg) that are removed from whey waste by foam fractionation method. The data is reproducible over a wide concentration range. This optimized method allowed analysis of BSA, α-La, β-Lg in a mixture within 5 min and could be applied to the analysis of a variety of commercial and laboratory whey products within a short time. 相似文献
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