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91.
92.
Todorov Vladislav T. Dutsov Chavdar Ch. Cassette Philippe Mitev Krasimir K. 《Journal of Radioanalytical and Nuclear Chemistry》2022,331(8):3249-3258
Journal of Radioanalytical and Nuclear Chemistry - This work shows a study of the effect of the non-uniformity of photocathode response on the energy resolution of plastic scintillators optimized... 相似文献
93.
A natural supersymmetric extension
is defined of the current (= affine Kac-Moody Lie) algebra
; it corresponds to a superconformal and chiral invariant 2-dimensional quantum field theory (QFT), and hence appears as an ingredient in superstring models. All unitary irreducible positive energy representations of
are constructed. They extend to unitary representations of the semidirect sumS
(G) of
with the superconformal algebra of Neveu-Schwarz, for
, or of Ramond, for =0.On leave of absence from the Institute for Nuclear Research and Nuclear Energy of the Bulgarian Academy of Sciences, BG-1184 Sofia, Bulgaria 相似文献
94.
95.
The title compounds were prepared by direct reactions of the corresponding elements at high temperature. They are isostructural with each other (monoclinic, P2(1)/m, Z = 2; Na(8)BaPb(6), a = 13.116(4), b = 5.351(1), and c = 16.166(5) A, beta = 108.07(2) degrees; Na(8)BaSn(6), a = 12.897(4), b = 5.362(1), and c = 16.826(5) A, beta = 108.19(2) degrees; Na(8)EuSn(6), a = 12.912(2), b = 5.220(1), and c = 15.721(2) A, beta = 108.09(1) degrees ) and contain isolated, flat, and aromatic pentagonal rings of Sn(5)(6)(-) and Pb(5)(6)(-) as well as isolated anions of Sn(4)(-) and Pb(4)(-). According to four-probe conductivity measurements, the tin compounds, Na(8)BaSn(6) and Na(8)EuSn(6), are semiconducting with band gaps of 0.11 and 0.09 eV, respectively, and are therefore electronically balanced. Magnetic measurements show that Na(8)BaSn(6) is diamagnetic while Na(8)EuSn(6) is paramagnetic and undergoes two transitions at low temperatures. 相似文献
96.
The title compound was synthesized in an attempt to produce stacked benzene-like Sn6(6-) rings separated by alkaline-earth cations in analogy with the recently reported stacks of aromatic cyclopentadienyl-like Sn5(6-) in Na8BaSn6 (in addition to isolated Sn4- anions). The resulting compound, synthesized from a stoichiometric mixture of the elements at high temperature, has the "correct" stoichiometry with six tin atoms and six positive charges. However, the rings of Sn6(6-) are puckered into chair-type cyclohexanes that are interconnected into isolated cylindrical tubes stuffed with Ca2+ between the rings. Such tubes, if fused to each other, form the hexagonal diamond structure. The new compound is electronically balanced according to magnetic and four-probe resistivity measurements. Reported are also the synthesis and properties of Na10EuSn12 and Na10YbSn12 which are isostructural with the known Na10CaSn12. 相似文献
97.
K. Todorov 《Archiv der Mathematik》1979,33(1):23-28
Ohne ZusammenfassungDiese Arbeit entstand während eines Aufenthaltes des Verfassers an der G.H. Kassel im Rahmen eines Humboldtstipendiums und wurde unterstützt von Prof. Bosbach, dem der Autor an dieser Stelle seinen Dank ausspricht. 相似文献
98.
Kaltscho Todorov 《Semigroup Forum》1979,17(1):387-388
Ohne ZusammenfassungDie Forschungsarbeit entstand mit Unterstützung der Alexander von Humboldt-Stiftung. 相似文献
99.
Nickola Stefanov Todorov 《International Journal of Theoretical Physics》1981,20(4):269-289
It is shown that the nonstationary Schrödinger equation does not satisfy a well-known adiabatical principle in thermodynamics. A renormalization procedure based on the possible existence of a time-irreversible basic evolution equation is proposed with the help of which one comes to agreement in a variety of specific cases of an adiabatic inclusion of a perturbing potential. The ideology of the present article IV rests essentially on the ideology of the preceding articles, in particular article I. 相似文献
100.
The distribution of center of mass electrophoretic mobility mobilities and normalized migration time of up to 1080 lambda DNA molecules per experiment were measured in both semidilute hydroxyethylcellulose HEC/0.5 x Tris-borate-EDTA (TBE) solutions and dilute HEC/0.5 x TBE solution by high-speed video microscopy. Measurements were made microscopically over a short migration distance in homogeneous DNA HEC/0.5 x TBE solution and after electrophoretic migration of a plug of DNA through 7 cm. Video at 120 frames/s (semidilute HEC solution) and 236 frames/s (dilute HEC solution) allowed visualization with adequate resolution for single molecule mobility measurements. The electrophoretic migration times and band shapes predicted from the measurements corresponded well with those measured by conventional capillary electrophoresis (CE) in both semidilute and dilute HEC. In semidilute solution, the band width predicted by a square root of time scaling is in good agreement with the results of conventional CE. However, in dilute solution the precision of the measurements was not good enough to allow scaled estimates of band widths. 相似文献