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71.
Journal of Thermal Analysis and Calorimetry - Electrical sensor has been considered in the current attempt. Combination of buoyancy, electric and radiative forces has been included in the governing...  相似文献   
72.
Journal of Thermal Analysis and Calorimetry - The significant bioconvection phenomenon with the utilization of nanoparticles encountered fundamental industrial and technological applications in...  相似文献   
73.
Aliev  A. R.  Heydarov  R. J. 《Doklady Mathematics》2019,100(2):436-439
Doklady Mathematics - The collocation method is justified for the integral equation of the impedance boundary value problem for the Helmholtz equation. A sequence is constructed that converges to...  相似文献   
74.
75.
Structure of isoxazoline compounds formed via the reaction of alkyl-substituted benzonitrile oxides with ethylene was determined by X-ray diffraction method. Isoxazoline ring is flattened, the bond lengths in it depend slightly on the nature of substituents (CH3, C2H5) and their position in the benzene ring and the angle of rotation relative to the isoxazoline ring. The connection N-O has a length 1.422 Å. Thermal decomposition of isoxazolines in a liquid phase (160–280°C) is accompanied by the release of acetaldehyde and aromatic nitrile. Both the structure of the cycle and its stability is practically independent of the structure of an aromatic substituent. The rate constant of the initial stage is characterized by the low significance of kinetic parameters, E = 104°8 kJ mol?1 and log a(A/c) = 7.2±0.8. The results obtained are rationalized in terms of biradical mechanism of isoxazoline ring-opening that includes an efficient recombination of the biradical and its disappearance as a result of synchronous multi-center rearrangement with the release of acetaldehyde.  相似文献   
76.
3-Aroyl-1H-pyrrolo[2,1-c][1,4]benzoxazine-1,2,4-triones reacted with 5,5-dimethylcyclohexane-1,3-dione to give 3′-aroyl-4′-hydroxy-1′-(2-hydroxyphenyl)-6,6-dimethyl-6,7-dihydrospiro[1-benzofuran-3,2′-pyrrole]-2,4,5′(1′H,5H)-triones. The crystalline and molecular structures of 3′-benzoyl-4′-hydroxy-1′-(2-hydroxyphenyl)-6,6-dimethyl-6,7-dihydrospiro[1-benzofuran-3,2′-pyrrole]-2,4,5′(1′H,5H)-trione were determined by X-ray analysis.  相似文献   
77.
The crystal structure of a new energetic compound of 4,4″-dinitro-[3,3′:4,3″]-tris-[1,2,5]-oxadiazole is studied.  相似文献   
78.
The effect of low-temperature annealing on the magnetization curve of YBa2Cu3O6 + x ceramics in the superconducting state (x ≈ 0.9) is investigated. When the annealing time is fairly long, the field dependence of magnetic moment M exhibits a feature in the form of a plateau, where the value of M remains almost constant. The evolution of this feature in the magnetization curves of annealed samples with annealing time and temperature is studied. It is assumed that low-temperature annealing gives rise to metastable ferromagnetic clusters in YBa2Cu3O6 + x ceramics, the contribution of which to the magnetic moment accounts for the feature in the magnetization curves of the annealed samples.  相似文献   
79.
Journal of Radioanalytical and Nuclear Chemistry - Thin natEr2O3 targets were irradiated on cyclotron by 60 MeV alpha particles. Thulium and ytterbium radioisotopes, formed during...  相似文献   
80.
We study the Cauchy problem for systems of weakly coupled Klein–Gordon equations with dissipations. We prove a theorem on the nonexistence of global solutions with positive initial energy.  相似文献   
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