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101.
We have studied isospin symmetry violation in nuclear reactions by measuring simultaneously the cross-section of the following
two reactionsp +d →3H π+ andp +d →3He π0. The experiment was perfomed at the cooler synchrotron accelerator COSY, Jülich at several beam energies close to the correspondingη production threshold. We also have ongoing programmes onη-nucleus final-state interaction studies viap+6 Li →7 Be +η reactions, high resolution search for dibaryonic resonances and lambda-proton final state interaction studies. The experimental
details and results obtained so far are presented here 相似文献
102.
黎勇 《数学物理学报(B辑英文版)》2007,27(2):437-448
In this article, two relaxation time limits, namely, the momentum relaxation time limit and the energy relaxation time limit are considered. By the compactness argument, it is obtained that the smooth solutions of the multidimensional nonisentropic Euler-Poisson problem converge to the solutions of an energy transport model or a drift diffusion model, respectively, with respect to different time scales. 相似文献
103.
104.
提出了一种制备偶数个多原子Greenberger-Horne-Zerlinger态的方案,它是基于原子-腔场相互作用.首先n个分离的腔初始时处于真空态,通过双光子转移,把n个腔制备成数态|2>和真空态|o>的缠结态.随后,与腔场发生共振相互作用的2n个等同的原子被分别送入n个腔,通过相互作用后,2n个原子处于GHZ态,而n个腔仍然处于真空态. 相似文献
105.
Time differential perturbed angular correlation measurements of the 133–482 keVγ-γ cascade of181Ta in Hf-doped YBa2Cu3O7−x
are presented. The181Hf precurser nuclei are incorporated into the sample by thermal neutron irradiation. Two quadrupole interaction frequencies
are observed in the as-irradiated sample:v
Q1=161±10 MHz with intensityf
1=75%, asymmetry parameterη
1=0.32 and damping parameter Λ1=0.42, andv
Q2=1108±40 MHz withf
2=25%,η
2=0.62, and Λ2=0.60. On annealing the sample in air at various temperaturesT
a and quenching to room temperature,f
1 remained nearly constant forT
a<600°C andv
Q1 for all annealing temperatures indicating that these are insensitive to oxygen stoichiometry. This frequency is interpreted
to be due to181Hf substitutingY sites. BeyondT
a=600°C,f
1 increased and reached a constant value of 90% forT
a=800°C. The value ofv
Q2 showed a slight variation between 1086 and 1160 MHz, whilef
2 remained nearly constant at 25% forT
a<600°C. This component is identified to be due to181Hf substituting Cu 1 sites in the Cu-O chains of YBCO. Above 600°Cv
Q2 decreased and reached a value of 808 MHz beyond 750°C. 相似文献
106.
J.-L. Garden 《Thermochimica Acta》2007,452(2):85-105
What is really measured in dynamic calorimetric experiments is still an open question. This paper is devoted to this question, which can be usefully envisaged by means of macroscopic non-equilibrium thermodynamics. From the pioneer work of De Donder on chemical reactions and with other authors along the 20th century, the question is tackled under an historical point of view. A special attention is paid about the notions of frequency dependent complex heat capacity and entropy production due to irreversible processes occurring during an experiment. This phenomenological approach based on thermodynamics, not widely spread in the literature of calorimetry, could open significant perspectives on the study of macro-systems undergoing physico-chemical transformations probed by dynamic calorimetry. 相似文献
107.
高密度氩气的原子间相互作用与状态方程 总被引:5,自引:4,他引:1
本文从高密度气体的原子间相互作用出发进行思考,在修改范德瓦耳方程的基础上,提出了一种新的适用于高密度气体的状态方程,并用以对氩气临界区的等温压缩线进行计算,结果与实验值很符合. 相似文献
108.
The phenomenological amplitude for the reaction πN→ππN fixed by fittings to the experimental data in the energy region 0.300 ≤P
Lab≤ 500 MeV/c is used for modelling the Chew–Low extrapolation and Olsson–Turner threshold approach. It is shown that the uncritical
application of the former results in enermous theoretical errors, the extracted values being in fact random numbers. The results
of the Olsson–Turner method are characterized by significant systematic errors coming from unknown details of the isobar physics.
Received: 10 December 1997 相似文献
109.
For the Boltzmann equation with small transfer of momentum, we derive a system of nonlinear integral-differential equations describing the logarithmic asymptotics of the solution to the Cauchy problem in the domain at the distanceO(1) from the support of the initial condition.Translated fromMatematicheskie Zametki, Vol. 64, No. 1, pp. 73–94, July, 1998.This research was partially supported by INTAS-RFBR under grant No. 95-91 in the case of the first author, and by INTAS under grant No. 96-0698 in the case of the second author. 相似文献
110.
Preparation of entangled simultaneous nonresonant atomic states through atom-field interaction
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A scheme is proposed for generating a three-atom maximal
entanglement W state. It is based on the simultaneous nonresonant
interaction of atoms with a single-mode cavity field. Our scheme is
insensitive to the cavity field, so the cavity field in our scheme
can be initially in thermal states. 相似文献