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141.
142.
A method is developed for the removal of redundancy which is known to plague the calculation of low lying spectra of odd mass nuclei by the equation of motion method. The feasibility of the method is verified numerically. 相似文献
143.
S Biswas R Chakraborti R Cowsik N Durgaprasad P J Kajarekar R K Singh M N Vahia J S Yadav N Dutt J N Goswami D Lal H S Mazumdar D V Subhedar M K Padmanabhan 《Pramana》1986,27(1-2):89-104
The measurements of the ionization states, composition, energy spectra and spatial distribution of heavy ions of helium to
iron of energies 10–100 MeV/amu in the anomalous cosmic rays are of major importance in understanding their origin which is
unknown at present.Anuradha (IONS) cosmic ray experiment in Spacelab-3 was designed to determine the above properties in near earth space and this had
a highly successful flight and operations aboard the shuttle Challenger at an orbital altitude of 352 km during 29 April to
6 May 1985. The instrument employs solid state nuclear track detectors (CR-39) of high sensitivity and large collecting area
of about 800 cm2 and determines the arrival time information of particles with active elements. Experimental methods, flight operations and
preliminary results are briefly described. Initial results indicate that relatively high fluxes of low energy cosmic ray α-particles,
oxygen group and heavier ions were obtained. The flight period corresponded to that of quiet Sun and the level of solar activity
was close to solar minimum. It is estimated that about 10,000 events of low energy cosmic ray alpha particles with time annotation
are recorded in the detector together with similar number of events of oxygen and heavier ions of low energy cosmic rays.
The authors felicitate Prof. D S Kothari on his eightieth birthday and dedicate this paper to him on this occasion. 相似文献
144.
145.
Raj Gandhi Subhendra Mohanty Tarun Souradeep S Agarwalla K Bhattacharya B Brahmachari R Crittenden S Goswami P Ghoshal M Lindner H S Mani S Mitra S Pascoli S Panda R Rangarajan S Ray T Roy Choudhury R Saha S Sarkar A Srivastava R Sheth S Uma Sankar U Yajnik 《Pramana》2006,67(4):735-742
The working group on astroparticle and neutrino physics at WHEPP-9 covered a wide range of topics. The main topics were neutrino
physics at INO, neutrino astronomy and recent constraints on dark energy coming from cosmological observations of large scale
structure and CMB anisotropy. 相似文献
146.
B. S. Tomar A. Goswami A. V. R. Reddy S. K. Das P. P. Burte S. B. Manohar Satya Prakash 《Zeitschrift für Physik A Hadrons and Nuclei》1992,342(2):223-227
Excitation functions for the evaporation residues for the reactions12C+93Nb and16O+89Y in the projectile energy range of 4 to 6.5 MeV/amu have been measured using off-line gamma spectrometry. The excitation functions for neutron(xn), proton(pxn) and one alpha(xn) emission channels are practically similar for both the reactions. However the products formed by two alpha(2xn) emission show much higher cross sections in the12C+93Nb than the16O+89Y system. This has been explained in terms of the incomplete fusion process involving transfer of an alpha particle from the projectile to the target in the former case.Authors thank Shri D.C. Ephraim for making the rolled metal foils and the operation crew of PELLETRON facility for their help in carrying out the irradiations. Authors are grateful to Dr. P.R. Natarajan, Head Radiochemistry Division for his keen interest in this work. 相似文献
147.
A. Goswami S. B. Manohar S. K. Das A. V. R. Reddy B. S. Tomar S. Prakash 《Zeitschrift für Physik A Hadrons and Nuclei》1992,342(3):299-301
Mass resolved fission fragment angular distribution was measured in the 28.5 MeV alpha induced fission of233U using recoil catcher technique and direct gamma spectrometry. The angular distribution of 8 fission products were obtained. The angular anisotropies of asymmetric fission products were found to be higher than those of symmetric products indicating a correlation between the fragment angular distribution and the mass distribution.The authors are grateful to Dr. S.K. Kataria and Dr. T. Datta for fruitful discussions. We thank the operation crew of the variable energy cyclotron, Calcutta for their help in carrying out the irradiations. Thanks are due to Dr. P.R. Natarajan, Head of the Radiochemistry Division for his keen interest in the work. 相似文献
148.
Asymmetric cyclopropanation of alkenes through diazo decomposition mediated by transition metal complexes is a widely investigated catalytic reaction to obtain cyclopropanes where high enantioselectivity is achieved by optimizing metal–ligand combination. Instead of a chronological listing of developments, this review illustrates the existing literature data according to the structural types of ligands in catalytic complexes and attempts to correlate substrate structure and selectivity with ligand design. 相似文献
149.
S. Bose A. Goswami K. S. Chaudhuri 《The Journal of the Operational Research Society》1995,46(6):771-782
An economic order quantity (EOQ) inventory model for deteriorating goods is developed with a linear, positive trend in demand allowing inventory shortages and backlogging. The effects of inflation and the time-value of money are incorporated into the model, considering two separate inflation rates: namely, the internal (company) inflation rate and the external (general economy) inflation rate. It is assumed that the goods in the inventory deteriorate over time at a constant rate θ. The inventory policy is discussed over a finite time-horizon with several reorder points. The results are discussed with a numerical example and a sensitivity analysis of the optimal solution with respect to the parameters of the system is carried out. Several particular cases of the model are discussed in brief. 相似文献
150.
The self-diffusion coefficient of water in Nafion-117 membrane in different cationic forms was measured by the transient radiotracer method, which is based on an analytical solution of Fick's second law. The self-diffusion coefficient of water in the membrane was obtained from the analysis of time-dependent isotopic-exchange rates of tritium tagged water between sample of Nafion-117 membrane and equilibrating water. This transient method does not require the knowledge of partition coefficient of water, which is an essential parameter in the radiotracer permeation method. In present work, self-diffusion coefficients of water in the Nafion-117 membrane with H+, Li+, Ag+, Na+, K+, Rb+ and Cs+ monovalent counterions were obtained. The values of logarithm of self-diffusion coefficients were found to vary linearly as a function of polymer volume fraction except for membrane sample with H+ counterions. The self-diffusion coefficient of water in Nafion-117 membrane with H+ counterions was significantly different from the trend observed in the variation of self-diffusion coefficient of water as a function of polymer volume fraction in the membrane with other monovalent counterions. This observation seems to suggest that the physical structure of Nafion-117 membrane in H+ form may be quite different from the Nafion-117 membrane with other monovalent counterions. The high self-diffusion coefficient of water (1.67 × 10−6 cm2/s) in Nafion-117 membrane with Cs+ counterions indicates that the ionic clusters in Nafion-117 membrane are well connected even at low water content (8.2 wt.%) in the membrane. 相似文献