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981.
P. A. Shreiner 《Algebra and Logic》1998,37(1):59-64
It is shown that a logic J
fd
*
characterized by all Kripke frames the domains of all nonmaximal worlds of which are finite lacks the Beth property. The
logic is the first example of an intermediate superintuitionistic logic without the Beth property. The interpolation and the
Beth properties are also proved missing in all predicate superintuitionistic logics which contain J
fd
*
and are contained in a logic characterized by frames of the form〈N
n
, ≤,{Dk}k∈N
n〉.
Supported by the Russian Foundation for Humanities, grant No. 97-03-04089.
Translated fromAlgebra i Logika, Vol. 37, No. 1, pp. 107–117, January–February, 1998. 相似文献
982.
A. P. Zhernov 《Physics of the Solid State》1998,40(10):1658-1660
The linear thermal expansion coefficient of crystal lattices of germanium with different isotopic compositions is analyzed.
Fiz. Tverd. Tela (St. Petersburg) 40, 1829–1831 (October 1998) 相似文献
983.
Time-resolved photoluminescence from porous silicon coated with a diamondlike carbon film is investigated. The intensity of
the photoluminescence from the carbon film is obserd to increase after deposition, and there is an accompanying change in
the intensity and a shortwavelength shift of the photoluminescence band of porous silicon that depends on the porosity of
its original layers. These changes are explained by the formation of carbon nanoclusters on the surface of the silicon filaments.
Zh. Tekh. Fiz. 68, 83–87 (April 1998) 相似文献
984.
J.M. Chatterjee S. Basu-Roy S.S. Ghugre S. Chattopadhyay R.P. Singh G.O. Rodrigues R.K. Chattopadhyay R.K. Bhowmik 《The European Physical Journal A - Hadrons and Nuclei》1998,1(1):55-59
A search for new isomers of nanosecond lifetimes were carried out in 153Eu via the 150Nd(7Li,xnγ) reaction. The single particle angular momentum alignment and dynamical moment of inertia estimated from the experimental
data indicate a configuration change at rotational energy ħω∼ 0.30 MeV. A decrease of B(E2) values is also observed at the
same frequency. An isomeric level is identified at an excitation energy of 3100 keV (Jπ=35/2−) which corresponds to this frequency. The lifetime of the level is found to be 8.6 ± 1.3 nanosecond.
Received: 22 April 1997 / Revised version: 26 September 1997 相似文献
985.
F. Schümann S. Zavatarelli L. Gialanella U. Greife M. Junker D. Rogalla C. Rolfs F. Strieder H.P. Trautvetter 《The European Physical Journal A - Hadrons and Nuclei》1998,2(4):337-342
Abstact: The elastic scattering cross sections, σ (E,θ), for the systems He+Ta and He+W have been measured at θlab=165° and E
lab=76.1 keV to 3.988 MeV using targets with a thickness of a few atomic layers. The results are smaller than the results given
by the Rutherford scattering law, σR(E,θ), due to the effects of electron screening and can be described by σ(E,θ)/σR(E,θ)=(1+Ue/E)−1, where U
e is an atomic screening potential energy. The deduced average value, U
e=28 ± 3 keV, is consistent with the Moliére- and Lenz-Jensen-models as well as electron binding energies.
Received: 25 May 1998 相似文献
986.
Y.K. Gambhir J.P. Maharana C.S. Warke 《The European Physical Journal A - Hadrons and Nuclei》1998,3(3):255-262
The existence of broken pseudo-spin symmetry in the Pb nucleus has been studied in the relativistic mean field approach using
realistic Lagrangian parameters. Its relationship to spin orbit splitting and the vanishingly small surface delta character
of the mean spin orbit potential are investigated. In the 208Pb nucleus the broken pseudo-spin doublets are found to exist above the neutron (proton) Fermi surfaces.
Received: 16 April 1998 / Revised version: 26 June 1998 相似文献
987.
988.
C. Ruyer-Quil P. Manneville 《The European Physical Journal B - Condensed Matter and Complex Systems》1998,6(2):277-292
A new model of film flow down an inclined plane is derived by a method combining results of the classical long wavelength
expansion to a weighted-residuals technique. It can be expressed as a set of three coupled evolution equations for three slowly
varying fields, the thickness h, the flow-rate q, and a new variable that measures the departure of the wall shear from the shear predicted by a parabolic velocity profile. Results of a preliminary
study are in good agreement with theoretical asymptotic properties close to the instability threshold, laboratory experiments
beyond threshold and numerical simulations of the full Navier-Stokes equations.
Received: 16 April 1998 / Revised: 29 June 1998 / Accepted: 2 July 1998 相似文献
989.
V. P. Starodub 《Technical Physics》1998,43(6):735-736
The mechanisms for formation of population inversions in plasma jets of lithium, sodium, cadmium, and strontium vapor are
studied. The primary contribution to forming a population inversion over the transitions of the alkali atoms is found to be
three-body electron-ion recombination, and for transitions between the ion levels of strontium and cadmium, inelastic collisions
with the buffer gas play an important role. Using helium instead of argon as a buffer leads to a substantial increase in the
magnitude of the inversion.
Zh. Tekh. Fiz. 68, 134–135 (June 1998) 相似文献
990.