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41.
Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 6, pp. 1466–1467, June, 1991.  相似文献   
42.
Inclusive production of direct soft photons is studied inK + p andK + π interactions at 250 GeV/c. Total cross sections, Feynman-x and transverse momentum distributions of direct γ's are presented. The measured cross sections are several times larger than expected from QED inner bremsstrahlung, indicating the presence of an anomalous soft photon source. The model of Lichard and Van Hove, based on the “cold quark-gluon plasma” picture, agrees with the data.  相似文献   
43.
The ionization of excited hydrogen-like atoms in a femtosecond laser pulse is studied by direct numerical integration of the time-dependent Schrödinger equation for a quantum system in the field of an electromagnetic wave. Expressions are obtained for the ionization probability of the system as a function of the parameters of the laser pulse and the initial state of the atom. Ionization suppression is found, confirming the basic premises of the theory of interference stabilization of Rydberg atoms.  相似文献   
44.
Results on the multiplicity structure of diffractively excited meson and proton systems in À+/K+ p interactions at 250 GeV/c are presented for diffractive masses up to about 9 GeV. The energy dependence of the average charge multiplicity and the shape of the multiplicity distribution in terms of KNO-scaling and negative binomial distribution are investigated. The diffractive systems are compared toe + e ,lh and non-diffractivehh final states as suggested by modern approaches of the Pomeron-hadron collision. Systematic differences are found between diffractive meson and proton systems but also between diffraction and the reactions compared to.  相似文献   
45.
Syntheses and molecular structures of the heterometallic complexes of nickel cyclopentadienyl triphenylphosphine tellurophenolate with tungsten carbonyls (II and III) (CIF files CCDC nos. 1559733 and 1559734, respectively) are described.  相似文献   
46.
The role of the atomic structure in the fracture processes is considered using borate, silicate, and phosphate glasses as an example. Primary attention is focused on the degree of connectivity of the atomic structure. It is shown that the degree of connectivity is a major factor responsible for the structural strength of glasses under conditions excluding the influence of both accidental surface defects and the environment. The change in the Young’s modulus as a measure of elastic deformation and the change in the hardness as a characteristic of irreversible deformation are analyzed. The ultimate elastic strain experienced by a glass at the instant of fracture is examined. It is found that the ultimate elastic strain is approximately equal to 10% for glasses with a three-dimensional atomic structure and 5% for glasses with a two-dimensional (layered) or chain structure. It is assumed that this behavior of the strength as a function of the degree of connectivity of the atomic structure is associated with the degree of uniformity of the external load distribution over atomic bonds.  相似文献   
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Cyclization with the formation of an N-N bond and simultaneous bromination, which lead to 3-bromo-1-pyrazoline 1,2-dioxides, apparently through a step involving the dinitroso derivative, occur in the reaction of sodium hypobromite with 1,3-hydroxylamino oximes. Dehydrobromination of the bromopyrazoline leads to the corresponding 3H-pyrazole. The same treatment of acetylacetone dioxime gives 4H-dibromo-3,5-dimethyl-4H-pyrazole 1,2-dioxide. which is readily hydrolyzed to the corresponding 4-oxo derivative. Data from the IR, UV, and PMR spectra are presented.  相似文献   
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