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111.
We study the possibility of detecting non-commutative QED through neutral Higgs boson pair production at a collider. This is based on the assumption that H0 interacts directly with the photon as suggested by symmetry considerations. The sensitivity of the cross-section to the non-commutative scale and the Higgs mass is investigated. Received: 28 August 2002 / Revised version: 15 November 2002 / Published online: 19 February 2003  相似文献   
112.
113.
The heat conductivity and thermomagnetic effects are investigated in Ag2Te of stoichiometric composition and compositions with excess Te and Ag in the 5–100 K domain. Experimental results are compared with a theoretical model of the heat conductivity that takes account of intraphonon processes and phonon scattering by the boundaries and point defects.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 6, pp. 41–45, June, 1990.  相似文献   
114.
The X-ray crystallographic analysis of 1,7-difluoro-1,1,3,5,7,7-hexanitro-3,5-diazaheptane has been carried out. We have also determined its sensitivity to mechanical actions and a set of calculated and experimental data on explosion characteristics.  相似文献   
115.
We investigate the correctness of the initial boundary value problem of longitudinal impact on a piecewise‐homogeneous semi‐infinite bar consisting of a semi‐infinite elastic part and finite length visco‐elastic part whose hereditary properties are described by linear integral relations with an arbitrary difference kernel. Introducing nonstationary regularization in boundary conditions and in the contact conditions, the well‐posedness of the considered problem is proved. Copyright © 2017 John Wiley & Sons, Ltd.  相似文献   
116.
Phase equilibria in the Tl5Te3-Tl9BiTe6-Tl5Te2Cl system were studied by differential thermal analysis (DTA), X-ray powder diffraction, and measurements of microhardness and also emf of concentration circuits with reference to a thallium electrode. A number of polythermal sections, the isothermal sections of the phase diagram at 760 and 800 K, and projections of the liquidus and solidus surfaces were constructed. It was shown that the system is characterized by the formation of unlimited solid solutions with the Tl5Te3 structure. The concentration dependences of the crystal lattice parameters, microhardness, and emf in the solid solutions were described.  相似文献   
117.
Alloys in the As2S3-TlAs2S2Se2 section of the As2S3-As2Se3-TlS ternary system were studied and a phase diagram was constructed using physicochemical methods (differential thermal analysis, microstructural analysis, X-ray powder diffraction, also microhardness and density measurements). The diagram in the As2S3-TlAs2S2Se2 section is a non-quasi-binary diagonal section of the As2S3-As2Se3-TlSe quasi-ternary system. It was found that all the alloys in the section under ordinary conditions are obtained in the vitreous state. At low As2S3 concentrations in the section, solid solutions form up to 2.5 mol %, and at low TlAs2S2Se2 concentrations, their extent is 3 mol %.  相似文献   
118.
Methyl 1-aryl-3-aroyl-4,5-dioxo-4,5-dihydro-1H-pyrrole-2-carboxylates reacted with 3-methyl-4-phenyl-1H-pyrazol-5-amine to give methyl 7-arylcarbamoyl-6-aroyl-2-methyl-3-phenylpyrazolo[1,5-a]-pyrimidine-5-carboxylates. The molecular and crystalline structures of methyl 6-benzoyl-7-(4-chlorophenylcarbamoyl)-2-methyl-3-phenylpyrazolo[1,5-a]pyrimidine-5-carboxylate were studied by X-ray analysis.  相似文献   
119.
5-Phenyl-4-ethoxycarbonyl-1H-pyrrole-2,3-diones react with acetonitriles and dimedone to form ethyl 2-amino-7,7-dimethyl-2′,5-dioxo-5′-phenyl-1′,2′,5,6,7,8-hexahydrospiro[chromene-4,3′-pyrrole]-4′-carboxylates. The crystal and molecular structure of ethyl 2-amino-1′-benzyl-7,7-dimethyl-2′,5-dioxo-5′-phenyl-3-cyano-1′,2′,5,6,7,8-hexahydrospiro[chromene-4,3′-pyrrole]-4′-carboxylate was proved by XRD analysis.  相似文献   
120.
Recyclization of 3-aroyl-1H-pyrrolo[1,2-a]quinoxaline-1,2,4(5H)-triones by the action of benzoic acid hydrazides gave N-[2,4-dihydroxy-5-oxo-3-(3-oxo-3,4-dihydroquinoxalin-2-yl)-2-aryl-2,5-dihydro-1H-pyrrol-1-yl]benzamides whose structure was proved by X-ray analysis.  相似文献   
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