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101.
15N-H-Coupling in 1, 3, 5-triphenylformazan derivatives demonstrates that these compounds are not resonance hybrids but tautomeric pairs. The position of the tautomeric equilibrium is a function of the substituents present in the phenyl nuclei on N-1 and N-5. 相似文献
102.
103.
A. I. Abramovich L. I. Koroleva A. V. Michurin O. Yu. Gorbenko A. R. Kaul’ M. Kh. Mashaev R. Szymczak B. Krzymanska 《Physics of the Solid State》2002,44(5):927-931
This paper reports on a study of the magnetic, transport, magnetotransport, elastic, and magnetoelastic properties of the R0.55Sr0.45MnO3 ceramics (R=Sm, Eu0.40Nd0.15, Tb0.25Nd0.30) with the same carrier concentration and identical tolerance factor but which differ in the cation disorder parameter σ2. It was found that the Curie temperature TC decreases linearly with increasing σ2. An increase in σ2 results in an increase in the maximum electrical resistivity and an increased jump in the temperature dependence of linear thermal expansion near TC, as well as in a decrease in magnetoresistance and magnetostriction. For T>TC, one observes an abrupt increase in magnetostriction, magnetization, and magnetoresistance in a critical FIeld HC1 which grows with increasing temperature. The value of HC1 determined at fixed T/TC decreases with increasing σ2. 相似文献
104.
A. B. Granovskii Yu. P. Sukhorukov A. V. Telegin V. D. Bessonov E. A. Gan’shina A. R. Kaul’ I. E. Korsakov O. Yu. Gorbenko J. Gonzalez 《Journal of Experimental and Theoretical Physics》2011,112(1):77-86
Complex experimental investigations of the structural, optical, and magneto-optical properties (magnetotransmission, magnetoreflection,
and transversal Kerr effect, as well as the magnetoresistance, of La0.7Ca0.3MnO3 epitaxial films indicate that magnetoreflection and magnetotransmission in manganite films can reach giant values and depend
strongly on the magnetic and charge homogeneity of the films, their thickness, and spectral range under investigation. It
has been shown that the optical enhancement of the magnetorefractive effect occurs in thin films as compared to manganite
crystals. In the region of the minimum of the reflectance near the first phonon band, the resonance-like magnetorefractive
effect has been observed, which is accompanied by change of the sign of the magnetoreflection. A model based on the theory
of the magnetorefractive effect has been proposed to qualitatively explain this behavior. 相似文献
105.
N,N‐Dimethylchlorosulfitemethaniminium chloride (SOCl2‐DMF) has been found to be an efficient reagent for the one‐pot synthesis of benzimidazoles and benzoxazoles in excellent yield by condensation of carboxylic acids with o‐phenylenediamine/2‐amino‐phenol. 相似文献
106.
This work deals with the relativistic, coordinate invariant theory of electromagnetic wave propagation in a nonhomogeneous medium that is spatially isotropic with respect to the generalized 4-velocity. The existence of a new superpotential for the electromagnetic field is established. The governing field equation for the superpotential is derived via a generalized Lorentz gauge condition for the electromagnetic potential and two new tensor identities involving the curvature tensor. The new field equation takes a simple form which reveals the effect of non-rigidity, rotation, acceleration, and incomplete material isotropy with respect to the Fermi frames as well as curvature and nonhomogeneous material properties. 相似文献
107.
108.
109.
A Gurtu P K Malhotra I S Mittra P M Sood SC Gupta VK Gupta GL Kaul LK Mangotra Y Prakash NK Rao ML Sharma 《Pramana》1974,3(5):311-322
This is a continuation of our earlier investigation (Gurtuet al 1974Phys. Lett. 50 B 391) on multiparticle production in proton-nucleus collisions based on an exposure of emulsion stack to 200 GeV/c beam at the NAL. It is found that the ratioR em = 〈n s〉/〈n ch〉, where 〈n ch〉 is the charged particle multiplicity in pp-collisions, increases slowly from about 1 at 10 GeV/c to 1·6 at 68 GeV/c and attains a constant value of 1·71 ± 0·04 in the region 200 to 8000 GeV/c. Furthermore,R em = 1·71 implies an effectiveA-dependence ofR A =A 0.18,i.e., a very weak dependence. Predictions ofR em on various models are discussed and compared with the emulsion data. Data seem to favour models of hadron-nucleon collisions in which production of particles takes place through adouble step mechanism,e.g., diffractive excitation, hydrodynamical and energy flux cascade as opposed to models which envisage instantaneous production. 相似文献
110.
Sufficient optimality conditions are obtained in the case of continuous time programming problems under the assumptions that (i) particular linear combinations of the components of the constraint function are quasiconvex and objective functional is pseudoconcave “almost everywhere,” (ii) a particular linear combination of constraint function and objective functional is pseudoconcave “almost everywhere”. 相似文献