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61.
A Saikia  D K Choudhury 《Pramana》1992,38(3):313-318
We obtain approximate solutions of Altarelli-Parisi equations beyond leading logarithmic approximation. Our results suggest quantitative utility of higher order terms in the structure function analysis of deep inelastic scattering.  相似文献   
62.
D K Choudhury  J K Sarma 《Pramana》1992,39(3):273-277
We present further analysis of the structure functions at low-x using the approximate solutions of Altarelli-Parisi equations recently reported by us. We also compare our results with non-perturbative and non-linear evolutions.  相似文献   
63.
在量子密钥分发系统中,私密放大是合法通信双方提取共享安全密钥的一个必不可少的环节.本文主要介绍了实现私密放大的两种加速算法,采用将两种加速算法进行有效组合的方法,既可以保证私密放大的安全性,同时又有效地减少了运算的操作次数.在连续变量量子密钥分发实验系统中,采用上述组合加速算法,实现了安全密钥的提取.  相似文献   
64.
王瑛琪  叶佳声  刘树田  张岩 《中国物理 B》2013,22(11):114202-114202
A new phase-correction method in a realistic loss superlens imaging system is theoretically predicted.The image resolution is enhanced using the near-field active phase-correction method.Resolvable separation between two slits has been significantly improved toλ/20 for the symmetrical superlens system andλ/12 for unsymmetrical system.  相似文献   
65.
We introduce an affine-invariant version of generating functions of symplectic transformations of affine symplectic spaces, together with a generalization for other symmetric symplectic spaces. The composition of these functions has a nice connection with the Moyal product.  相似文献   
66.
Multi-Fractal Formalism for Quasi-Self-Similar Functions   总被引:1,自引:0,他引:1  
The study of multi-fractal functions has proved important in several domains of physics. Some physical phenomena such as fully developed turbulence or diffusion limited aggregates seem to exhibit some sort of self-similarity. The validity of the multi-fractal formalism has been proved to be valid for self-similar functions. But, multi-fractals encountered in physics or image processing are not exactly self-similar. For this reason, we extend the validity of the multi-fractal formalism for a class of some non-self-similar functions. Our functions are written as the superposition of similar structures at different scales, reminiscent of some possible modelization of turbulence or cascade models. Their expressions look also like wavelet decompositions. For the computation of their spectrum of singularities, it is unknown how to construct Gibbs measures. However, it suffices to use measures constructed according the Frostman's method. Besides, we compute the box dimension of the graphs.  相似文献   
67.
The dissociation constant of l-acetyl-2-(coumariniminecarboxamide-3-yl) hydrazine (ACCH) has been determined potentiometrically in 0.1 M KC1 and 40% (v/v) ethanol-water mixture. The stepwise stability constants of the formed complexes of Mn2+, Co2+, Ni2+, Cu2+, Zn2+ and UO2 2+ with ACCH have been determined. The stability constants were found to UO2 2+ > Cu2+> Zn2+ > Ni2+ < CO2+ < Mn2+. The effect of temperature on the dissociation of ACCH and the stability of its formed complexes were studied. The corresponding thermodynamic functions were also determined and discussed. The spectral data of ACCH were investigated in pure organic solvents as well as in Britton Robinson buffer solutions of varying pH values. The dissociation constant pKH 1 of ACCH and the overall stability constants logβ of their complexes were determined in 20% (v/v) ethanol-water mixture at 298K.  相似文献   
68.
Pseudo-dielectric functions ?ε1(E)? and ?ε2(E)? of triglycine sulfate (TGS) crystal have been obtained in the range of 7–33 eV for different temperatures close to ferroelectric phase transition by spectral ellipsometry using the synchrotron radiation source BESSY II. These dielectric functions ε1(E) and ε2(E) have also been calculated from first principles using CASTEP CAmbridge Serial Total Energy Package code together with the band structure and density of electronic states of the crystal. Experimental and theoretical dielectric functions agree satisfactorily. A characteristic decrease of temperature dependences of the dielectric losses tgδ(T) and related values just below the phase transition temperature T c have been found and discussed.  相似文献   
69.
An exposition of some methods of proving exponential (stretched exponential) decay of correlations is given. One-dimensional strictly hyperbolic and quadratic maps and two-dimensional piecewise smooth, uniformly hyperbolic maps are considered. The emphasis is on the fundamental constructions of the Markov sieve method due to Bunimovich-Chernov-Sinai and those of Liverani's Hilbert metric method.  相似文献   
70.
By employing Hirota bilinear method and Riemann theta functions of genus one,explicit triply periodic wave solutions for the(2+1)-dimensional Boussinesq equation are constructed under the Backlund transformation u =(1 /6)(u0 1) + 2[ln f(x,y,t)] xx,four kinds of triply periodic wave solutions are derived,and their long wave limit are discussed.The properties of one of the solutions are shown in Fig.1.  相似文献   
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