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91.
M K Parida Nita Sinha B Adhikary B Allanach A Alok K S Babu B Brahmachari D Choudhury E J Chun P K Das A Ghosal D Hitlin W S Hou S Kumar H N Li E Ma S K Majee G Majumdar B Mishra G Mohanty S Nandi H Pas M K Parida S D Rindani J P Saha N Sahu Y Sakai S Sen C Sharma C D Sharma S Shalgar N N Singh S Uma Sankar N Sinha R Sinha F Simonetto R Srikanth R Vaidya 《Pramana》2006,67(5):849-860
This is the report of flavor physics and model building working group at WHEPP-9. While activites in flavor physics have been
mainly focused on B-physics, those in model building have been primarily devoted to neutrino physics. We present summary of working group discussions
carried out during the workshop in the above fields, and also briefly review the progress made in some projects subsequently. 相似文献
92.
We report the ac conductivity and relaxation behavior analysis for a heterogeneous polymer–clay nanocomposite (PNC) having
composition (polyacrylonitrile)8LiCF3SO3 + x wt.% dodecylamine modified montmorillonite. Charge transport behavior in an ionically conducting PNC has been analyzed systematically
and correlated with the macroscopic parameters like polymer glass transition temperature and available free mobile charge
carriers. Intercalation of cation coordinated polymer into the nanometric clay channels has been confirmed by high-resolution
transmission electron microscopy. The electrical properties of the intercalated PNC films have been studied using complex
impedance/admittance spectroscopy. Excellent correlation of relaxation behavior with polymer glass transition temperature
(T
g) confirmed the objectives of the work. An analysis of dielectric relaxation indicates that PNC films are lossy when compared
with polymer–salt film. This result is a direct outcome of faster ion dynamics leading to strong electrode polarization effect
due to the accumulation of charge carriers at the interface. 相似文献
93.
Egodapitiya KN Sharma S Hasan A Laforge AC Madison DH Moshammer R Schulz M 《Physical review letters》2011,106(15):153202
We have measured the scattering angle dependence of cross sections for ionization in p+H2 collisions for a fixed projectile energy loss. Depending on the projectile coherence, interference due to indistinguishable diffraction of the projectile from the two atomic centers was either present or absent in the data. This shows that, due to the fundamentals of quantum mechanics, the preparation of the beam must be included in theoretical calculations. The results have far-reaching implications on formal atomic scattering theory because this critical aspect has been overlooked for several decades. 相似文献
94.
Sharma VK Mitra S Kumar A Yusuf SM Juranyi F Mukhopadhyay R 《J Phys Condens Matter》2011,23(44):446002
Here we report the dynamical behaviour of water in Prussian blue analogue (PBA) Cu(0.75)Mn(0.75)[Fe(CN)(6)]·7H(2)O molecular magnet in the temperature range 260-360 K as studied using the quasielastic neutron scattering technique. While significant quasielastic broadening is observed in the hydrated sample, no broadening was observed in the dehydrated one. Data analysis showed that the observed quasielastic broadening in Cu(0.75)Mn(0.75)[Fe(CN)(6)]·7H(2)O corresponds to the dynamics of the non-coordinated water molecules at the 32f site and the coordinated water molecules at the 24e site, existing in the cavities created by the absence of Fe(CN)(6) units. The non-coordinated water molecules at 8c interstitial sites do not contribute to the broadening, suggesting that they are immobile at least within the time window of the spectrometer used. Behaviour of the elastic incoherent structure factor is consistent with the model where the water molecules undergo translational diffusion localized within the cavity of 5.1 ?. While all the non-coordinated water molecules at the 32f site are dynamic over the entire range of temperatures, the coordinated ones at the 24e site become progressively dynamic with temperature. The water molecules were found to undergo hindered (~1.16 × 10(-5) cm(2) s(-1) at 300 K) diffusion compared to bulk water and the diffusivity followed Arrhenius behaviour within the measured temperature range with an activation energy of 1.26 kcal mol(-1). 相似文献
95.
J. Goswamy A. Sharma D. Mehta B. Chand N. Singh P. N. Trehan P. Singh R. G. Pilley H. G. Devare R. K. Bhowmik C. R. Praharaj 《Zeitschrift für Physik A Hadrons and Nuclei》1992,344(2):233-234
High spin states in 120Xe, populated via107Ag(16O, p2n) and108Pd(16O, 4n)reactions have been studied using γ-ray spectroscopic techniques. 21 new transitions have been added to extend the level scheme. Two S-bands are extended upto 26+ and 22+;these bands are found to cross the g. s band at hΩ=0. 39 and 0. 47 MeV. The band structures have been discussed within the framework of CSM. 相似文献
96.
97.
The consequences of 50 MeV Li3+ ion irradiation (fluence: 5×1013 ions/cm2) on the structural and electrical properties of the Y3+xFe5?xO12 (x=0.0, 0.2, 0.4 and 0.6) garnet system have been investigated over the temperature range of 300–673 K. It is found that the percentage formation of an additional yttrium orthoferrite phase observed along with the bcc garnet phase considerably reduces for x=0.4 and 0.6 compositions after swift heavy ion (SHI) irradiation. The nature of thermal variation of DC resistivity curves for x=0.0 and 0.2 compositions is different from that for x=0.4 and 0.6 compositions. The SHI irradiation influences the magnitude of DC resistivity and conduction mechanism for the single-phase compositions while for mixed-phase compositions they remain unaffected. The results have been explained in the light of replacement of magnetic (5μB), smaller (0.64 Å), Fe3+ ion by nonmagnetic (0μB), larger (0.89 Å), Y3+ ion, the presence of the yttrium orthoferrite phase and swift heavy ion irradiation-induced paramagnetic centers in the system. 相似文献
98.
Kriti Sharma Alaa S. Al-Kabbi G.S.S. Saini S.K. Tripathi 《Current Applied Physics》2013,13(6):964-968
Nanocrystalline cadmium selenide (nc-CdSe) thin films have been prepared by thermal evaporation using the inert gas condensation (IGC) technique. Transmission electron microscopy (TEM) studies show that the CdSe nanocrystals (NCs) are spherical in shape. Constant photocurrent method (CPM) is used to determine the value of absorption coefficient in low absorption region of as-deposited, annealed and light soaked nc-CdSe thin films. Values of optical band gap (Eg) have been determined by using Tauc's relation for as-deposited, annealed and light soaked nc-CdSe thin films from the α values evaluated from reflection and transmission measurements. We have used a derivative procedure to sub-gap absorption spectra in order to get information on the energetic distribution of the occupied density of states below Fermi level. Constants such as optical gap Eg, Urbach edge Eu have been obtained from CPM spectra in as-deposited, annealed and light soaked nc-CdSe thin films. Concentration of defect states has also been calculated in as-deposited, annealed and light soaked nc-CdSe thin films. 相似文献
99.
100.
We investigate the mean first passage time of an active Brownian particle in one dimension using numerical simulations. The activity in one dimension is modelled as a two state model; the particle moves with a constant propulsion strength but its orientation switches from one state to other as in a random telegraphic process. We study the influence of a finite resetting rate r on the mean first passage time to a fixed target of a single free active Brownian particle and map this result using an effective diffusion process. As in the case of a passive Brownian particle, we can find an optimal resetting rate r* for an active Brownian particle for which the target is found with the minimum average time. In the case of the presence of an external potential, we find good agreement between the theory and numerical simulations using an effective potential approach. 相似文献