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121.
We obtain a solution of the DGLAP equation for the gluon at low x first by expanding the gluon in a Taylor series and then using the method of characteristics. We test its validity by comparing
it with that of Glück, Reya and Vogt. The convergence criteria of the approximation used are also discussed. We also calculate
εF
2(x,Q)2/ε In Q
2 using its approximate relations with the gluon distribution at low x. The predictions are then compared with the HERA data. 相似文献
122.
S. C. L. Gerritzen M. Kaufman L. Rosenthaler M. Roy S. Camilla J. Großfeld S. H. Bertram C. Stiebel G. W. Jennings R. D. Lewis J. Pritzker R. Jungkunz P. Bruère A. Fourmont W. L. Roberts H. A. Schuette J. K. Chowdhury S. M. Das-Gupta A. L. Bernoullie 《Analytical and bioanalytical chemistry》1933,92(11-12):451-461
123.
Vijaya S. Joshi Sanjoy K. Chowdhury Amitabha Sarkar 《Journal of Chemical Sciences》1995,107(4):447-458
Structural chemistry of organometallic complexes containing pyrazolederived polydentate ligands (without boron) has been reviewed
in the context of current results from this laboratory.
NCL Communication No. 6137 相似文献
124.
125.
126.
Swapan K. Chowdhury Stephen D. Cameron Donald M. Cox Krzysztof Kniaz Robert A. Strongin Maria A. Cichy John E. Fischer Amos B. Smith 《Journal of mass spectrometry : JMS》1993,28(8):860-866
Electron-capture negative ion chemical ionization (EC-NICI) and field desorption (FD) mass spectrometric techniques were utilized to examine polyfluorinated C60. Two different samples from the same preparation, one prior to sublimation and the other sublimed material, were investigated. From the raw non-sublimed product in EC-NCI six series of ions corresponding to different numbers of attached oxygen atoms were obtained, which are represented by the formula [C60F2nOm]?, where n ranged from 0 to 30 and m from 0 to 5. The sublimed material in EC-NICI produced the same six series of ions with up to 48 fluorine atoms attached to C60. The field desorption of the same sample produced similar results, but the signal-to-noise ratios of the spectra were low. Both samples, in the two different techniques examined, yielded C60F60 ions with only an even number of fluorine atoms attached. The present investigation, for the first time, provides direct experimental evidence for the existence of higher fluorinated C60 up to C60F60 and multiple oxides of polyfluoro-C60 with up to five oxygen atoms attached. 相似文献
127.
The elastic scattering of low-energy α-particles by a 4He target has been analysed within the frame-work of a modified Regge-Pole model which reproduces the partial wave phaseshifts in an elegant and simple way and describes all other relevant features of the scattering phenomena. 相似文献
128.
Swapna Roy A. Roy Chowdhury Mrityunjoy De 《International Journal of Theoretical Physics》1988,27(1):47-55
It is demonstrated that Lie point symmetries associated with a nonlinear equation for short waves in three dimensions generate an infinite-dimensional Lie algebra—a loop Algebra. Classification of the independent sets of the subalgebra is done through the adjoint action of the corresponding generators. Different forms of similarity solutions are discussed. 相似文献
129.
Two important configurations of Yang-Mills fields are discussed applying to them the Painleve test of Ablowitz. The case with a constant electric E-field does not admit an exact solution while the cylindrically symmetric self-dual system admits an inverse scattering approach for instanton solution. 相似文献
130.
Different kinds of mean-field theories (MFT) of spin glasses (SG) are reviewed. A brief introductory review of major experimental results, which have to be explained theoretically, is presented in the beginning. Marshall-Klein-Brout type random local field theories are described qualitatively. Edwards-Anderson MFT of SG transition is introduced after defining the various relevant order parameters. Almost all the static and dynamic approaches to the solution of the Sherrington-Kirkpatrick model are reviewed in detail. The existence of mixed phase(s) in the MFT of vector SG is examined critically in the light of recent theories and experiments. The existence of macroscopic anisotropy energy in SG and their microscopic origin are mentioned. The upper and lower critical dimensionalities obtained by different authors are enlisted. The concept of frustration and its deeper connection with other branches of human knowledge are indicated. Nonlinear susceptibilities, spin wave and relaxational modes in SG are also reviewed. The two-level-system picture of SG, its physical basis and important consequences are presented. The Tholence-Tournier-Wohlfarth phenomenological cluster model of SG is discussed with a stress on the role of measurement time. SG transition has been described as percolation and localization-delocalization problems. Some special features of the local field distribution in SG are mentioned. Some results of computer simulation on the various models of SG are summarized. The theories of the transport properties of SG are enlisted. Recent trends in the theory of SG are indicated at the end. 相似文献