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排序方式: 共有3004条查询结果,搜索用时 15 毫秒
41.
KM Varier AM Vinodkumar NVSV Prasad PV Madhusudhana Rao DL Sastry Lagy T Baby MC Radhakrishna NG Puttaswamy JJ Das P Sugathan N Madhavan AK Sinha DO Kataria 《Pramana》1999,53(3):529-533
Large enhancements have been observed in the sub-barrier fusion cross sections for Ti+Ni systems in our previous studies.
Coupled channel calculations incorporating couplings to 2+ and 3− states failed to explain these enhancements completely. A possibilty of transfer channels contributing to the residual enhancements
had been suggested. In order to investigate the role of relevant transfer channels, measurements of one- and two-nucleon transfer
were carried out for 46,48Ti+61Ni systems. The present paper gives the results of these studies. 相似文献
42.
Mata Prasad Jaiswal 《Rendiconti del Circolo Matematico di Palermo》1969,18(1):40-48
In this paper two different generalisations of the Stieltjes transform have been given along with their inversion formulae. The results are given in the form of two theorems. These two theorems yield many known generalisations of the transform in question as particular cases on specializing the parameters involved therein. 相似文献
43.
Conventional design of radiation detectors uses sintered ceramic insulating modules. The major drawback of these ceramic components
is their inherent brittleness. Ion chambers, in which these ceramic spacers are replaced by metallic components with plasma
spray coated alumina, have been developed in our Research Centre. These components act as thin spacers that have good mechanical
strength as well as high electrical insulation and replace alumina insulators with the same dimensions. As a result, the design
of the beam loss monitor ion chamber for CAT could be simplified by coating the outer surface of the HT electrode with alumina.
One of the chambers developed for isotope calibrator for brachytherapy gamma sources has its outer aluminium electrode (60
mm dia × 220 mm long) coated with 250 μ thick alumina (97%) + titania (3%).
In view of potential applications in neutron-sensitive ion chambers used in reactor control instrumentation, studies were
carried out on alumina 100 μ to 500 μ thick coatings on copper, aluminium and SS components. The electrical insulation varied
from 108 ohms to 1012 ohms for coating thicknesses above 200 μ. The porosity in the coating resulted in some fall in electrical insulation due
to moisture absorption. An improvement could be achieved by providing the ceramic surface with moisture-repellent silicone
oil coating. Irradiation at Apsara reactor core location showed that the coating on aluminium was found to be unaffected after
exposure to 1017 nvt fluence. 相似文献
44.
Sunanda Banerjee Rohini M Godbole Sreerup Raychaudhuri Ben Allanach Sunanda Banerjee Satyaki Bhattacharyya Debajyoti Choudhury Siba Prasad Das Anindya Datta Rohini M Godbole Monoranjan Guchait Sabine Kraml Gobinda Majumdar David Miller Margarete Mühlleitner Nobuchika Okada Maxim Perelstein Santosh K Rai Sreerup Raychaudhuri Saurabh D Rindani DP Roy K Sridhar Rishikesh Vaidya D Zeppenfeld 《Pramana》2006,67(4):617-637
This is summary of the activities of the working group on collider physics in the IXth Workshop on High Energy Physics Phenomenology
(WHEPP-9) held at the Institute of Physics, Bhubaneswar, India in January 2006. Some of the work subsequently done on these
problems by the subgroups formed during the workshop is included in this report. 相似文献
45.
Mode-selective dynamics of triatomic molecule in the electronic ground state under continuous wave laser pulse is investigated
for the discrete vibrational bound states. A non-perturbative approach has been used to analyse the vibrational couplings
and dynamics of the molecule. 相似文献
46.
Neeraj Kumar Giri 《Optics Communications》2008,281(13):3547-3552
Upconversion emission and energy transfer processes in singly, doubly and triply doped tellurite glasses have been studied under 798 and 980 nm laser excitations. Emissions have been observed at 482, 544, 584, 655 nm and at 477, 655, 698, 800 nm corresponding to Tb3+: 5D4 → 7F6, 7F5, 7F4, 7FJ (J = 0, 1, 2, 3) and Tm3+: 1G4 → 3H6, 1G4 → 3F4, 3F3 → 3H6, 3H4 → 3H6 transitions, respectively. Among Tm3+, Yb3+and Tb3+ ions only Tm3+ has a ground state absorption at 798 nm excitation due to 3H4 ← 3H6 transition. For 980 nm excitation only Yb3+ can absorb the incident radiation. However, for both types of excitations, emission from all the three ions Tb, Yb and Tm has been observed. Possible mechanisms are proposed as follows: under 798 nm excitation Tm3+ ions are excited which excite Yb3+ ions through energy transfer. Finally “cooperative energy transfer” from a pair of Yb3+ ions to Tm3+ and Tb3+ ions takes place. Under 980 nm excitation Yb3+ ions absorb the incident energy and excite Tm3+ and Tb3+ ions via cooperative energy transfer. Variation of emission intensity with the ion concentrations of Yb3+, Tm3+ and Tb3+ has been studied. The lifetime of the 1G4 level has also been measured. 相似文献
47.
Anomalous phase synchronization in nonidentical interacting oscillators is manifest as the increase of frequency disorder prior to synchronization. We show that this effect can be enhanced when a time-delay is included in the coupling. In systems of limit-cycle and chaotic oscillators we find that the regions of phase disorder and phase synchronization can be interwoven in the parameter space such that as a function of coupling or time-delay the system shows transitions from phase ordering to disorder and back. 相似文献
48.
Prasad Varanasi Sunil Sarangi 《Journal of Quantitative Spectroscopy & Radiative Transfer》1974,14(9):845-859
Collision-broadened line widths in CO-CO2 and CO-O2 collisions have been calculated by incorporating interactions due to octopoles and hexadecapoles and short range repulsive interactions into Anderson's theory. It is shown how these higher-order interactions can be manipulated to yield good agreement with experimental data. A critical evaluation of this totally empirical manipulation suggests that a thorough revision of the theory is required for all but simple dipole-dipole interactions. In the process of the evaluation, the values of the multipole moments are discussed. 相似文献
49.
For decades, organizational researchers have employed standard statistical methods to uncover relationships among variables and constructs. However, in complex organization systems, the prevalence of non-linearity and outliers is to be expected. Under such circumstances, the use of standard statistical methods becomes unreliable and, correspondingly, results in degraded predictions of the relationships within the organizational systems. We describe the use of neural network analyses to model team effectiveness so as to provide more accurate predictions for managers. 相似文献
50.
A.S. Joshi P.A. Naik S. Barnwal Y.B.S.R. Prasad P.D. Gupta 《Optics Communications》2010,283(23):4713-763
Diagnostic information about the self-generated magnetic fields (SGMF) generated in laser produced plasmas is normally obtained by measuring the Faraday rotation angle (FRA) of a linearly polarized laser probe beam passing through the plasma. Simultaneous recording of the corresponding interferogram is required to get the density information necessary for estimating the magnetic field. The problem with this method is that the visibility of the fringes in the interferogram can be poor, and the SGMF cannot be calculated in the regions where the interference fringes are not observable. In this paper, we propose a new method to obtain the density distribution and the SGMF from two simultaneous measurements of FRA using two probe beams of different colors, which allows one to calculate the SGMF without the need of interferometry. 相似文献