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排序方式: 共有839条查询结果,搜索用时 78 毫秒
1.
This paper presents results of studies on dc electrical conductivity and transference number measurements on potassium bromate
(KBrO3) complexed polyvinyl chloride (PVC) films prepared by solution cast technique. Temperature dependence of dc electrical conductivity
and transference number data indicated the dominance of ion type charge transport in these specimens. The magnitude of conductivity
increased with increase in concentration of the salt and temperature. Using this (PVC + KBrO3) electrolyte, solid-state electrochemical cells were fabricated, and their discharge profiles were studied under a constant
load of 100 kΩ. Several cell profiles such as open circuit voltage, short circuit current, power density, and energy density
associated with these cells were evaluated and were reported. The features of complexation of the electrolytes were studied
by X-ray diffraction and Fourier transform infrared spectroscopy.
Paper presented at the Third International Conference on Ionic Devices (ICID 2006), Chennai, Tamilnadu, India, Dec. 7–9, 2006 相似文献
2.
We consider the rate of convergence for a class of perturbed hemivariational inequalities in reflexive Banach Spaces. Our results can be viewed as an extension and refinement of some previous known results in this area. 相似文献
3.
We study a generalized Crank–Nicolson scheme for the time discretization of a fractional wave equation, in combination with
a space discretization by linear finite elements. The scheme uses a non-uniform grid in time to compensate for the singular
behaviour of the exact solution at t = 0. With appropriate assumptions on the data and assuming that the spatial domain is convex or smooth, we show that the
error is of order k
2 + h
2, where k and h are the parameters for the time and space meshes, respectively. 相似文献
4.
E. Casarejos P. Armbruster L. Audouin J. Benlliure M. Bernas A. Boudard R. Legrain S. Leray B. Mustapha S. Czajkowski T. Enqvist B. Fernandez J. Pereira M. Pravikoff F. Rejmund K. -H. Schmidt C. Stephan J. Taieb L. Tassan-Got C. Villagrasa C. Volant W. Wlazlo 《Physics of Atomic Nuclei》2003,66(8):1413-1420
The isotopic production cross sections of heavy residues in relativistic heavy-ion collisions have been investigated in inverse kinematics. The primary reaction products were fully identified in mass and atomic number prior to beta decay using the fragment separator FRS. The huge collection of data obtained helps in the understanding of the two main reaction mechanisms involved: fragmentation and fission. These data provide basic information for future radioactive ion beam facilities and for technical applications like intense neutron sources by means of spallation targets. 相似文献
5.
P. Boccaccio L. Vannucci R.A. Ricci G. Vannini R. Dona I. Massa J.P. Coffin P. Fintz G. Guillaume F. Jundt F. Rami P. Wagner 《The European Physical Journal A - Hadrons and Nuclei》1998,1(4):399-406
We studied the sequential binary decay of the systems 32S+45Sc, 76Ge, 89Y, 59Co, 63Cu and 19F+63Cu induced by collisions at ≃6 MeV·A. The two stages of the process have reaction-times compatible with the dynamics of different mechanisms. The study of the
excitation energy partition shows that the reaction mechanism of the first step has influence on the de-excitation of the
primary fragments producing two decay components which have different time scale.
Received: 25 March 1997 / Revised version: 2 December 1997 相似文献
6.
Phase Transitions in the Early Universe with Negatively Induced Supergravity Cosmological Constant
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EL-NABULSI Ahmad Rami 《中国物理快报》2006,23(5):1124-1127
We consider that the observable cosmological constant is the sum of the vacuum (Avac) and the induced term (Aind - 3m^2/4) with m being the ultra-llght masses (≈ Hubble parameter) implemented in the theory from supergravities arguments and non-minimal coupling. In the absence of a scalar buildup of matter fields, we study its effects on spontaneous symmetry breaking with a Higgs potential and show how the presence of the ultra-light masses yields some important consequences for the early universe and new constraints on the Higgs and electroweak gauge bosons masses. 相似文献
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M. A. Misdaq S. Berrazzouk A. Elharti F. Ait Nouh W. Bourzik 《Journal of Radioanalytical and Nuclear Chemistry》2000,246(2):395-401
Uranium and thorium contents were evaluated in water samples collected from different sources of the piedmont of the Middle Atlas mountains by using two types of solid state nuclear track detectors (SSNTD). In addition, the radon (222Rn) and thoron (220Rn) -activities per unit volume of the water samples were also determined. The influence of the water flow rate and altitude on the radon concentration of the water samples belonging to the piedmont of the Middle Atlas mountains was investigated. The hydraulic exchanges between the Middle Atlas water reservoirs and the Turonian aquifer of the neighbouring Tadla plain have been quantified. The results were compared with data given in literature. 相似文献