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91.
In the framework of R-parity violating (R(p)) supersymmetry, we try to find a consistent explanation for both recently measured CP asymmetry in B0 --> phi K(S) decay and the large branching ratio of B+/- --> eta'K+/- decay, which are inconsistent with the standard model (SM) prediction. We also investigate other charmless hadronic B -- >PP and B --> VP decay modes whose experimental data favor the SM: for instance, recently measured CP asymmetries in B0 --> eta(')K(S) and B0 -- >J/Psi K(S). We find that all the observed data can be accommodated for certain values of R(p) couplings. 相似文献
92.
In this paper we introduce the notion of operator semirings of a -semiring to study -semirings. It is shown that the lattices of all left (right) ideals (two-sided ideals) of a -semiring and its right (respectively left) operator semiring are isomorphic. This has many applications to characterize various -semirings.AMS Subject Classification (2000): 16Y60, 16Y99 相似文献
93.
Shamita Dutta Gupta Xiaotie She 《Proceedings of the American Mathematical Society》2000,128(8):2203-2212
In this paper, we obtain an Euler product with functional equation associated to a noncuspidal metaplectic form on the double cover of . Zagier's idea of Rankin-Selberg method is used to define the convolution of and the -function.
94.
Xu W Dutta D Xiong F Anderson B Auberbach L Averett T Bertozzi W Black T Calarco J Cardman L Cates GD Chai ZW Chen JP Choi S Chudakov E Churchwell S Corrado GS Crawford C Dale D Deur A Djawotho P Filippone BW Finn JM Gao H Gilman R Glamazdin AV Glashausser C Glöckle W Golak J Gomez J Gorbenko VG Hansen JO Hersman FW Higinbotham DW Holmes R Howell CR Hughes E Humensky B Incerti S de Jager CW Jensen JS Jiang X Jones CE Jones M Kahl R Kamada H Kievsky A Kominis I Korsch W Kramer K Kumbartzki G 《Physical review letters》2000,85(14):2900-2904
We have measured the transverse asymmetry A(T') in 3He(e,e(')) quasielastic scattering in Hall A at Jefferson Laboratory with high precision for Q2 values from 0.1 to 0.6 (GeV/c)(2). The neutron magnetic form factor G(n)(M) was extracted based on Faddeev calculations for Q2 = 0.1 and 0.2 (GeV/c)(2) with an experimental uncertainty of less than 2%. 相似文献
95.
A. Saha A. Ray S. Mukhopadhyay P.K. Datta P.K. Dutta S.M. Saltiel 《Applied physics. B, Lasers and optics》2007,87(3):431-436
An all-solid-state, side diode array pulse pumped Nd:YAG laser tunable for six wavelengths ranging from 1318.8 nm to 1356.0 nm
is developed. The tunability is obtained by using a grating in Littrow mode that also serves as an output coupler. The configuration
ensures a line width as low as 0.04 nm. Thermal effects limit the maximum average power to 250 mW for an average absorbed
pump power of 8.0 W in the free-running condition. An acousto-optic Q-switching of the laser provides pulses of width 251 ns
with peak power of 733 W for an average pump power of 11.5 W. The laser may find application in microsurgery and dermatology.
PACS 42.55.Xi; 42.60.-v; 42.60.Fc; 42.60.Gd; 42.62.Be 相似文献
96.
Rupankar PairaArindam Maity Shyamal MondalSubhendu Naskar Krishnendu B. SahuPritam Saha Abhijit HazraE. Padmanaban Sukdeb BanerjeeNirup B. Mondal 《Tetrahedron letters》2011,52(14):1653-1657
Basic alumina supported solvent-free one-pot synthesis of pyridine-fused polycyclic diazepaniums was achieved under microwave irradiation. The process was successfully extended to the synthesis of pyridine-fused bicyclic imidazolidiniums and tetrahydro-pyrimidiniums and also of tri- and tetracyclic diaza-heterocycle-fused quinoliniums. The dual characteristic of basic alumina, a solid support as well as a base, was successfully employed in the current investigation. The method emerged to be an effective route in terms of product yield, reaction time, and ease of purification and most importantly for environment friendly protocols. 相似文献
97.
Shyamalee GogoiMandakini Dutta Junali GogoiRomesh Chandra Boruah 《Tetrahedron letters》2011,52(7):813-816
A microwave-promoted and base-catalyzed synthesis of cycl[3.2.2]azines is accomplished in water via a three-component reaction (3-CR) of 2-picoline, α-bromoacetophenone and alkyne. The extension of the methodology to the synthesis of steroidal and carbocyclic cycl[3.2.2]azine is also reported. 相似文献
98.
J.D. Schwarzkopf C.T. Crowe J.J. Riley S. Wetchagarun P. Dutta 《International Journal of Multiphase Flow》2009
This study focuses on understanding how the presence of particles, in homogeneous turbulence decay, affects the dissipation of dissipation coefficient within the volume averaged dissipation transport equation. In developing this equation, the coefficient for dissipation of dissipation was assumed to be the sum of the single phase coefficient and an additional coefficient that is related to the effects of the dispersed phase. Direct numerical simulation was used to isolate the effect of stationary particles in homogeneous turbulent decay at low Reynolds numbers (ReL = 3.3 and 12.5). The particles were positioned at each grid point and modeled as point forces and a comparison was made between a 643 and 1283 domain. The results show that the dissipation of dissipation coefficient correlates well with a dimensionless parameter called the momentum coupling factor. 相似文献
99.
Polycrystalline samples of Fe-modified PLZT (lead lanthanum zirconate titanate) are prepared by a mixed-oxide reaction technique.
The formation of the compound has been confirmed by X-ray powder diffraction studies. The unit cell structure of the material
has been found to be rhombohedral. Fourier-transform infrared reflection (FTIR) spectra have been recorded to correspond the
structural changes associated with the phase formation. The effects of Fe concentration on the microstructure and dielectric
constant of PLZT materials have been investigated. The ferroelectric phase transition of PLFZT materials is studied using
dielectric measurements, which shows a shift in the transition temperature towards the higher-temperature side with increased
Fe ion concentration. The piezoelectric constants of this system are investigated by the same way of changed contents of Fe
ion in the main PLZT compound. The optimum values of Qm, kp, and d33 are 73, 0.32 and 406. The electrical conductivity increases with the increase in Fe ion concentration.
PACS 77.80.Bh; 77.84.Dy; 77.22.Ch; 72.15.Eb; 06.60.Ei; 39.30.+w 相似文献
100.
Anjan Biswas Abhijit Bandyopadhyay Nikhil K. Singha Anil K. Bhowmick 《Journal of polymer science. Part A, Polymer chemistry》2008,46(24):8023-8040
Direct sulfonation and styrene‐mediated sulfonation were carried out onto metallocene‐based poly(ethylene‐co‐octene) (POE) and poly(ethylene‐co‐butene) (PBE) elastomers to impart polarity on the completely nonpolar rubbery matrices and to prepare a new class of elastomer. The influence of styrene‐grafting and pendant chain length on the degree of sulfonation was also studied. The effects of sulfonation, styrene grafting and styrene‐mediated sulfonation at their optimized levels on various physicomechanical properties were thoroughly investigated, and the resultant properties were correlated with structures of the modified elastomers. Higher extent of sulfonic acid groups were introduced through direct sulfonation in comparison with the styrene‐mediated sulfonation, whereas better thermal and mechanical properties were obtained through styrene‐mediated sulfonation in comparison with the direct sulfonation process. PBE had shown higher degree of sulfonation and percentage grafting than POE. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 8023–8040, 2008 相似文献