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81.
The scale invariance technique has been employed to discuss theη
i-driven turbulent transport under a new fluid model developed by Kimet al [1]. Our analysis reveals that the finite Larmour radius effect plays a decisive role to determine the scaling behaviour
of the energy transport under the new fluid model. However, the overall scaling of the transport coefficient remains unchanged
as compared to that derived by Connor [2] under the traditional fluid model. The approximations considered by Connor [2] are
qualified with additional requirements within the new fluid approach. In the dissipative case, which has not been discussed
earlier, additional constraints on the power scaling laws of the transport properties are imposed due to the dissipative mechanisms
in the basic governing equations. 相似文献
82.
Anindita Bhattacharjee 《Journal of Molecular Spectroscopy》2005,232(2):264-278
We have studied the feasibility of amplification without population inversion (AWI) in LiH molecule for three-level ladder, V, and Λ schemes. We have shown the salient features of AWI in a molecular system in comparison to that in an atomic system, viz. the dependence of gain profile on the choice of different rotational and vibrational transitions. Under different three-level schemes, the effect of homogeneous and inhomogeneous broadening on the gain profile has been studied. We have also studied the dependence of gain on different external parameters. The temporal evolution of gain has been analyzed and it was found that AWI is achievable in both the transient and the steady state regime. For all the three-level schemes and in particular for the ladder scheme, amplification of the weak probe was obtained using a coupling laser of smaller frequency. 相似文献
83.
Bharati Bhattacharjee Manabendra N. Bhattacharjee Mitra Bhattacharjee Apurba K. Bhattacharjee 《国际化学动力学杂志》1985,17(6):629-636
The kinetics of the oxidation of naphthalene and phenanthrene by pyridinium fluorochromate, C5H5NHCrO3F, PFC, has been studied. The main product of the oxidation is the corresponding quinone. While each oxidation, studied in aqueous acetic acid (80–95%, v/v) medium, is first order with respect to the oxidant, the rate is almost independent of the substrate concentration. The reactions are catalyzed by acid, the acid-catalyzed reactions being very fast, which precluded determination of their order in acid medium. The kinetic isotope effect, kH/kD is 5.50 at 303 K for naphthalene. The reaction does not induce polymerization of acrylonitrile. The effects of temperature and solvent compositions were studied and activation parameters evaluated. Probable mechanisms are discussed. 相似文献
84.
We carry out a systematic analysis of ΔB = 2 interactions in supersymmetric theories. The selection rules in ΔB = 2 transition depend on the relative value of M (the mass scale that characterizes the ΔB = 2 interactions) and Λs (the super-symmetry-breaking scale). In particular, if M ? 104GeV and Λs ~ 102GeV, the effective ΔB = 2 interactions induce NN annihilation in a nucleus yielding two kaons in the final state while processes with only one or zero kaons are suppressed by mixing angles. On the other hand, if M ? 104GeV, then supersymmetry does not imply any additional selection rules beyond those of ordinary (non-supersymmetric) theories. 相似文献
85.
Because of the critical slowing down of the order parameter fluctuations, they do not follow the temperature oscillations produced adiabatically by a pressure wave. The resulting hysteresis leads to the observed dispersion and attenuation of ultrasound. The effect depends entirely upon the frequency dependent specific heat. We discuss here the mathematical features of this function, including it dynamic scaling properties. 相似文献
86.
Ajit Kumar Ray
B. Banerjee
B. Bhattacharjee
《International Journal of Non》1992,27(6):1007-1014Non-linear static behaviour of rhombic plates has been analysed following Banerjee's hypothesis (B. Banerjee, Large deflections of polygonal plates under non-stationary temperature. J. Thermal Stresses 7, 285–292 (1984)). Calculations have been carried out for different skew angles. To test the accuracy of the theoretical results so obtained, experiments were carried out on copper and steel rhombic plates. The theoretical results were found to be in excellent agreement with those obtained from an analysis of the experimental data. 相似文献
87.
A parallel algorithm for depth-first searching of a directed acyclic graph (DAG) on a shared memory model of a SIMD computer is proposed. The algorithm uses two parallel tree traversal algorithms, one for the preorder traversal and the other for therpostorder traversal of an ordered tree. Each of these traversal algorithms has a time complexity ofO(logn) whenO(n) processors are used,n being the number of vertices in the tree. The parallel depth-first search algorithm for a directed acyclic graphG withn vertices has a time complexity ofO((logn)2) whenO(n
2.81/logn) processors are used. 相似文献
88.
Sukhendu B. Bhattacharjee Tapan Ganguly Gayaram Bhaumik 《Photochemistry and photobiology》1985,41(2):153-158
Abstract— Holding of acriflavine sensitizedV–79 cells in growth medium before visible light exposure decreases inactivation by visible light. The decrease depended upon the period of holding, indicating that there was release of cellular dye during this period. Exposures to visible light were done in two conditions: (a) with no dye in the medium during visible light exposure (washed) and (b) with dye in the medium during exposure (unwashed). Caffeine was found to slightly increase the sensitivity of the cells to visible light in the washed condition, whereas, in the unwashed condition no such effect was observed. Interaction studies with far UV did not reveal any correlation between photodynamic damage and UV damage. Visible light exposure of acriflavine sensitized cells was found to be mutagenic, as studied from the induction of 8-azaguanine resistant mutants. Inhibition of singlet oxygen production by sodium azide suppressed the induction of mutants. All these, taken together, have been discussed with respect to the relative importance of DNA and non-DNA damage in the photodynamic action of acriflavine. 相似文献
89.
The model of randomly oriented single-ion uniaxial anisotropy field is extended to the case of antiferromagnetic exchange interaction between rare-earth ions. A self-consistent two-spin cluster approximation is used to calculate the magnetization curves for a model system of spin 1. The results are in good qualitative agreement with experimental data on amorphous RExCu1?x and RExAg1?x alloys (RE = Tb, Dy, Ho). In particular, the observed increase of the “coercive” field with increasing x in RExCu1?x alloys is accounted for. 相似文献
90.