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751.
B. Mukhopadhyaya S. Raychudhuri K. Agashe B. Allanach D. Bailin B. Brahmachari U. Chattopadhyay D. Choudhury P. Das Amitava Datta Anindya Datta A. Djouadi A. Giri K. Huitu A. Kundu U. Mahanta S. Moretti B. Mukhopadhyaya J. C. Pati A. K. Ray A. Raychaudhuri S. Raychaudhuri P. Roy N. Singh R. Vaidya 《Pramana》2003,60(2):395-399
752.
It has been suggested that the pair annihilation of dark matter particles chi with mass between 0.5 and 20 MeV into e+e- pairs could be responsible for the excess flux (detected by the INTEGRAL satellite) of 511 keV photons coming from the central region of our Galaxy. The simplest way to achieve the required cross section while respecting existing constraints is to introduce a new vector boson U with mass M(U) below a few hundred MeV. We point out that over most of the allowed parameter space, the process e+e--->U(gamma), followed by the decay of U into either an e+e- pair or an invisible (nu(-)nu or chi(-)chi) channel, should lead to signals detectable by current B-factory experiments. A smaller, but still substantial, region of parameter space can also be probed at the Phi factory DAPhiNE. 相似文献
753.
At Trombay, lattice dynamics studies employing coherent inelastic neutron scattering (INS) experiments have been carried out
at the two research reactors, CIRUS and Dhruva. While the early work at CIRUS involved many elemental solids and ionic molecular
solids, recent experiments at Dhruva have focussed on certain superconductors (cuprates and intermetallics), geophysically
important minerals (Al2SiO5, ZrSiO4, MnCO3) and layered halides (BaFCl, ZnCl2). In most of the studies, theoretical modelling of lattice dynamics has played a significant role in the interpretation and
analysis of the results from experiments. This talk summarises the developments and current activities in the field of inelastic
neutron scattering and lattice dynamics at Trombay. 相似文献
754.
Mathematical Notes - We investigate the Hyers–Ulam–Rassias stability property of a quadratic functional equation. The analysis is done in the context of modular spaces. The type of... 相似文献
755.
M S Samant R P Anand R K Choudhury S S Kapoor K Kumar D M Nadkarni A Saxena 《Pramana》1993,40(4):299-309
The emission spectra of prompt fission neutrons from mass and kinetic energy selected fission fragments have been measured
in235U(n
th,f). Neutron energies were determined from the measurement of the neutron time of flight using a NE213 scintillation detector.
The fragment energies were measured by a pair of surface barrier detectors in one set of measurements and by a back-to-back
gridded ionization chamber in the second set of measurements. The data were analysed event by event to deduce neutron energy
in the rest frame of the emitting fragment for the determination of neutron emission spectra and multiplicities as a function
of the fragment mass and total kinetic energy. The results are compared with statistical model calculations using shell and
excitation energy dependent level density formulations to deduce the level density parameters of the neutron rich fragment
nuclei over a large range of fragment masses. 相似文献
756.
Adcox K Adler SS Ajitanand NN Akiba Y Alexander J Aphecetche L Arai Y Aronson SH Averbeck R Awes TC Barish KN Barnes PD Barrette J Bassalleck B Bathe S Baublis V Bazilevsky A Belikov S Bellaiche FG Belyaev ST Bennett MJ Berdnikov Y Botelho S Brooks ML Brown DS Bruner N Bucher D Buesching H Bumazhnov V Bunce G Burward-Hoy J Butsyk S Carey TA Chand P Chang J Chang WC Chavez LL Chernichenko S Chi CY Chiba J Chiu M Choudhury RK Christ T Chujo T Chung MS Chung P Cianciolo V Cole BA D'Enterria DG 《Physical review letters》2001,87(5):052301
757.
758.
Partha Guha Barun Khanra A. Ghose Choudhury 《Nonlinear Analysis: Theory, Methods & Applications》2010,72(7-8):3247-3257
We employ the generalized Sundman transformation method to obtain certain new first integrals of autonomous second-order ordinary differential equations belonging to the Painlevé–Gambier classification scheme. This method not only yields systematically the known first integrals of a large number of the Painlevé–Gambier equations but also some time dependent ones, which greatly simplify the computation of their corresponding solution. In addition we also compute the Sundman symmetries of these equations. 相似文献
759.
Prasoon Kumar Khalid Baig Mirza Kaushik Choudhury Magali Cucchiarini Henning Madry Pratyoosh Shukla 《Advanced functional materials》2021,31(31):2009663
Tissue engineering is a systematic approach of assembling cells onto a 3D scaffold to form a functional tissue in the presence of critical growth factors. The scaffolding system guides stem cells through topological, physiochemical, and mechanical cues to differentiate and integrate to form a functional tissue. However, cellular communication during tissue formation taking place in a reactor needs to be understood properly to enable appropriate positioning of the cells in a 3D environment. Hence, sensors and actuators integrated with cyber-physical system (CPS) may be able to sense the tissue microenvironment and direct cells/cellular aggregates to an appropriate position, respectively. This can facilitate better cell-to-cell communication and cell–extracellular matrix communication for proper tissue morphogenesis. Advancements are made in the field of smart scaffolds that can morph cells/cellular aggregates after sensing the cellular microenvironment in a desired 3D architecture by providing appropriate cues. Recent scientific developments in the additive manufacturing technology have enabled the fabrication of smart scaffolds to create structural and functional tissue constructs. Sensors/actuators, cyber-systems, smart materials, and additive manufacturing put together is expected to lead to improved tissue-engineered medical products. The present review aims to highlight the possibilities of advancement of BioCPS for tissue engineering and regenerative medicine. 相似文献
760.
Mathematical Notes - The Banach Contraction Mapping Principle has many generalizations and extensions in different directions. Here we define $$(varepsilon,psi)$$ -Uniformly Local Weak... 相似文献