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排序方式: 共有1392条查询结果,搜索用时 31 毫秒
991.
du Rietz R Ekman J Rudolph D Fahlander C Dewald A Möller O Saha B Axiotis M Bentley MA Chandler C de Angelis G Della Vedova F Gadea A Hammond G Lenzi SM Mărginean N Napoli DR Nespolo M Rusu C Tonev D 《Physical review letters》2004,93(22):222501
Following the heavy-ion fusion-evaporation reaction 32S+24Mg at 95 MeV beam energy the lifetimes of analogue states in the T(z)=+/-1/2 A=51 mirror nuclei 51Fe and 51Mn have been measured using the Cologne plunger device coupled to the GASP gamma-ray spectrometer. The deduced B(E2;27/2(-)-->23/2(-)) values afford a unique opportunity to probe isoscalar and isovector polarization charges and to derive effective proton and neutron charges, epsilon(p) and epsilon(n), in the fp shell. A comparison between the experimental results and several different large-scale shell-model calculations yields epsilon(p) approximately 1.15e and epsilon(n) approximately 0.80e. 相似文献
992.
Room temperature, light promoted trimerization of a monomeric complex [Cu(HL)(L)](NO(3)).H(2)O (HL =N,N-dimethyl-N[prime or minute]-propylsalicylideneimine) dissolved in CH(2)Cl(2), was observed with the concomitant generation of new ligand moiety (ClCH(2)L). 相似文献
993.
A. Paul A. Saha S. Bandopadhyay B. Dutta-Roy 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2007,42(3):495-499
Tunneling delay times of wavepackets in quantum mechanical penetration of
rectangular barriers have long been known to show a perplexing independence
with respect to the width of the barrier. This also has relevance to the
transmission of evanescent waves in optics. Some authors have claimed that in
the presence of absorption or inelastic channels (which they model by taking a
complex barrier potential) this effect no longer exists, in that the time delay becomes proportional to the barrier width.
Taking the point of view that
complex potentials imply non-Hermitian Hamiltonians and are as such fraught
with conceptual pit-falls particularly in connection to problems involving
time evolution, we have constructed a two-channel model which does not suffer
from such limitations in order to examine this issue. We find that the
conclusions arrived at by the earlier authors need to be more precisely
specified. 相似文献
994.
Dip N. Mahato R. H. Pink S. R. Badu R. H. Scheicher Archana Dubey H. P. Saha Lee Chow Mahendra K. Mahanti M. B. Huang T. P. Das 《Hyperfine Interactions》2007,174(1-3):15-20
The LPCTrap facility is coupled to the low-energy beam line LIRAT of the SPIRAL source at GANIL (France). The facility comprises
an RFQ trap for beam preparation and a transparent Paul trap for in-trap decay studies. The system has been tested for several
ion species. The Paul trap has been fully characterized for 6Li+ and 23Na+ ions. This characterization together with GEANT4 simulations of the in-trap decay setup (Paul trap and detection system)
has permitted to predict the effect of the size of the ion cloud on the decay study of 6He+. 相似文献
995.
996.
A new inexpensive and practical apparatus for solid-phase chemistry and parallel synthesis is described. This new apparatus fills an important void in the availability of portable tools for the synthesis of libraries of compounds in multi-milligram amounts. Individual reaction tube capacities range in size from 4 mL to 500 mL of operating liquid volume. Reaction blocks of 36 tubes x 4 mL or 24 tubes x 150 mL allow flexibility of operation. Insert tubes with frit ends function as filter sticks for resin wash and for maintenance of inert atmosphere. An electronic controller device connects to the reaction tubes for programmable entry of pulses of inert gas for resin mixing or vacuum for resin wash. The utility of this apparatus is illustrated by the synthesis of libraries based on 4-methaneamine imidazoles. 相似文献
997.
Sarika Bhide V. M. Datar Satyajit Jena S. D. Kalmani N. K. Mondal G. K. Padmashree B. Satyanarayana R. R. Shinde P. Verma 《Pramana》2007,69(6):1015-1023
We are currently developing and studying the performance of glass RPC prototypes, under the INO detector R&D programme. While
we were successful in building and characterising a large number of chambers using local glass, these have met with severe
aging problems after a few months of continuous operation. We have then built a couple of RPCs using a Japanese glass. We
report in this paper on our long term stability tests of these RPCs. We also present some of our recent results on tracking
of cosmic ray muons in a stack of glass RPCs.
India-based Neutrino Observatory Collaboration 相似文献
998.
Platchkov S Pomatsalyuk R Prout DL Punjabi VA Pussieux T Quemener G Ransome RD Ravel O Roblin Y Roche R Rowntree D Rutledge GA Rutt PM Saha A Saito T Sarty AJ Serdarevic-Offermann A Smith TP Soldi A Sorokin P Souder P Suleiman R Templon JA Terasawa T Todor L Tsubota H 《Physical review letters》2000,84(15):3265-3269
We have measured the cross section for quasielastic 1p-shell proton knockout in the 16O(e,e(')p) reaction at omega = 0.439 GeV and Q2 = 0.8 (GeV/c)(2) for missing momentum P(miss)=355 MeV/c. We have extracted the response functions R(L+TT), R(T), R(LT), and the left-right asymmetry, A(LT), for the 1p(1/2) and the 1p(3/2) states. The data are well described by relativistic distorted wave impulse approximation calculations. At large P(miss), the structure observed in A(LT) indicates the existence of dynamical relativistic effects. 相似文献
999.
A crystal field analysis of the experimental results on the magnetic susceptibilities and their anisotropies in Ho(OH)3 and Tb(OH)3 was made with a view to resolve the previous anomalies observed in the results of specific heat studies. A pronounced thermal effect on lattice specific heat has been observed in Ho(OH)3 but not in Tb(OH)3. For Er(OH)3, the total specific heat was calculated with reasonable assumptions over a wide temperature range, but no experimental data are yet available for comparison. 相似文献
1000.