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61.
62.
A facile transformation of pentasubstituted tribromophenol derivatives to the corresponding alkyl-substituted dibromo-p-benzoquinones has been achieved using PbO2 as oxidizing agent in combination with 60% aq HClO4 in acetone in 70-72% yields. The electrochemical properties of these quinones were studied by means of cyclic voltammetry and compared with p-benzoquinone (BQ) and 2,3-dichloro-5,6-dicyano-benzoquinone (DDQ) recorded under identical experimental conditions. 相似文献
63.
D. Bhoi P. Mandal P. Choudhury S. Dash A. Banerjee 《Physica C: Superconductivity and its Applications》2011,471(7-8):258-264
The magnetization of the PrFeAsO0.60F0.12 polycrystalline sample has been measured as functions of temperature and magnetic field (H). The observed total magnetization is the sum of a superconducting irreversible magnetization and a paramagnetic magnetization. Analysis of dc susceptibility χ(T) in the normal state shows that the paramagnetic component of magnetization comes from the Pr3+ magnetic moments. The intragrain critical current density (JL) derived from the magnetization data is large. The JL(H) curve displays a second peak which shifts towards the high-field region with decreasing temperature. In the low-field region, a plateau up to a field H* followed by a power law H?5/8 behavior of JL(H) is the characteristic of the strong pinning. A vortex phase diagram for the present superconductor has been obtained from the magnetization and resistivity data. 相似文献
64.
The Higgs sector is extended in R -symmetric supersymmetry theories by two iso-doublets Rd,u which complement the standard iso-doublets Hd,u. We have analyzed masses and interactions of these novel states and describe their [non-standard] decay modes and their production channels at the LHC and e+e− colliders. 相似文献
65.
Anurag Jayswal Sarita Choudhury Ram U. Verma 《Journal of Applied Mathematics and Computing》2014,45(1-2):87-97
A new class of exponential form of vector variational-like inequality problems is introduced, and then the equivalence among (weakly) efficient solutions, vector critical points of vector optimization problem and the solutions of vector variational-like inequalities under the framework of (p,r)-invexity is established. To the best our knowledge, the presented results are new and highly application oriented to other results based on generalized invexities to the context of optimization problems in the literature. 相似文献
66.
Thomas M. Baker Lisa A. Sloan Lokman H. Choudhury Masahito Murai David J. Procter 《Tetrahedron: Asymmetry》2010,21(9-10):1246-1261
A cascade reaction involving sequential conjugate reduction, stereoselective aldol cyclisation and chemoselective lactone reduction mediated by SmI2–H2O provides access to a cyclopentanol bearing two vicinal quaternary stereocentres with good stereocontrol. The functionalised cyclopentanol product has been converted to a key intermediate in ongoing asymmetric studies towards stolonidiol. 相似文献
67.
Debajyoti Choudhury Saurabh D. Rindani B. Ananthanarayan K. R. S. Balaji Debajyoti Choudhury Manuel Drees Shashikant Dugad Gautam Dutta Sukanta Dutta Naveen Gaur Ambar Ghosal Walter Grimus Ernest Ma Shubhendra Mohanty P. N. Pandita M. K. Parida Subhendu Rakshit Saurabh D. Rindani D. P. Roy Probir Roy Sarira Sahu N. N. Singh Sudhir K. Vempati Francesco Vissani 《Pramana》1998,51(1-2):305-311
This report summarises the activities of the working group on ‘Physics beyond the Standard Model’. The results of investigations
in incorporatingR-parity in grand unification, the possibility of a light charged Higgs boson in extension of MSSM and radiative generation
of neutral vector boson self-couplings within the MSSM are described. Also given is an account of activities in neutrino physics,
namely a proposal for a study of the atmospheric muon anomaly in deep underground mines, a field theoretic study of neutrino
oscillations and a mechanism to generate appropriate masses of three active plus one sterile neutrino species. 相似文献
68.
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
69.
Supriya Mukherjee A. Ghose Choudhury A. Roy Chowdhury 《International Journal of Theoretical Physics》2006,45(4):820-834
We investigate the relation between the local variables of a discrete integrable lattice system and the corresponding separation variables, derived from the associated spectral curve. In particular, we have shown how the inverse transformation from the separation variables to the discrete lattice variables may be factorized as a sequence of canonical transformations. 相似文献
70.
The paper essentially deals with the analysis of photonic band-gap fibers in analogy with the electron wave motion in periodic crystal lattice. As such, the analyses are based on Bloch formulation. The dispersion characteristics of such fibers are presented by considering some illustrative values of design parameters. The effect of design parameters on the dispersion characteristics is also presented in terms of the variation of widths of allowed and forbidden bands of band-gap fibers. It is found that the number of allowed bands increases with the increase in difference between refractive indices of different layers. Further, widths of the allowed and forbidden bands increase with the increase in layer thickness. 相似文献