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141.
A. SzytuŁa A.T. Pȩdziwiatr Z. Tomkowicz W. Bażela 《Journal of magnetism and magnetic materials》1981,25(2):176-186
The crystal and magnetic properties of CoMnGe, CoFeGe, FeMnGe and NiFeGe compounds are investigated with X-ray, neutron diffraction, magnetometric and Mössbauer effect methods. All compounds have hexagonal Ni2In-type crystal structure and ferromagnetic properties at low temperatures (except for NiFeGe). Neutron diffraction experiments indicate that the compounds CoMnGe and CoFeGe have a collinear magnetic structure while FeMnGe a noncollinear. The magnetic moments are localized only on Mn and Fe atoms and lie in the basal plane. 相似文献
142.
Łukasz Stettner 《European Journal of Operational Research》1983,13(2):195-196
143.
144.
J. Ławrynowicz 《Reports on Mathematical Physics》1974,5(2):203-217
A class of capacities is introduced on pseudo-riemannian manifolds. They arise as a natural counterpart of the well-known plane quasiconformal capacities and their higher dimensional analogues which have been studied extensively in the recent years by F.W. Gehring, R. Kühnau and others. The capacities in question are shown to be either conformal invariants or conformal quasi-invariants, and, in the latter case, exact bounds are established. We thus arrive at the notion of quasiconformal mappings of pseudo-riemannian manifolds, which correspond to the inhomogeneous media. These mappings are studied briefly and the physical interpretation of some of the capacities in question is also given. 相似文献
145.
The vibrational spectra of nickel and magnesium α-pyrophosphates and of potassium and sodium α-pyroarsenates were found. A normal coordinate analysis was carried out for both P2O7 and As2O7 molecular systems using the force field of the Urey-Bradley-Shimanouchi type and the C2v symmetry model. On the basis of the results obtained the significant differences between the temperatures of the α/β phase transitions observed for Mg (68 °C) and Ni (565 °C) pyrophosphates have been explained. 相似文献
146.
147.
A stochastic radiation-filled world model is constructed in which the equation of state is perturbed with a “white noise”. The corresponding Fokker-Planck equation is solved. It turns out that the maximum probability path of the world's evolution is that of the Friedman model. However, singularities are no obstacles for the stochastic evolution, and σ2 → ∞ as t → ∞. 相似文献
148.
Broniatowski M Vila Romeu N Dynarowicz-Łatka P 《The journal of physical chemistry. B》2006,110(7):3078-3087
This work presents the results of phase behavior studies of two-dimensional (2D) binary systems involving semifluorinated alkanes (SFAs) and fatty alcohols. Four different SFAs were selected for investigations: (i) with a short and branched perfluorinated moiety (iF3H20), (ii) with a short and normal perfluorinated chain (F4H20), (iii) with a long and branched perfluorinated fragment (iF9H20), and (iv) with a long and normal perfluorinated group (F10H20). Two alcohols were selected to mix with the above-mentioned SFAs: tetradecanol and docosanol. The measurements were based on surface pressure/area isotherms in addition to Brewster angle microscope (BAM) imaging. Dependencies of the collapse surface pressure and the compression modulus vs the monolayer composition together with the excess free energy of mixing values, complemented with BAM images, enabled us to draw some general conclusions regarding the phase behavior of the investigated mixed systems. Generally, it has been noticed that the addition of docosanol into an SFA monolayer exerts a condensing effect, contrary to tetradecanol. Moreover, SFAs with a long perfluorinated segment mix to a larger extent with alcohols as compared to their analogues having a short perfluorinated moiety. The resultant phase diagrams for all the investigated eight mixtures are presented and discussed. 相似文献
149.
The air stable asarone-derived Ru carbene 16, a robust olefin metathesis catalyst, can be easily separated after reaction by deposition on silica gel and reused up to nine times. This procedure provides products of excellent purity with low Ru content. 相似文献
150.
Jarosław Łazuka 《Mathematical Methods in the Applied Sciences》2020,43(17):10115-10137
This paper is devoted to the investigation of the solution to the Cauchy problem for a system of partial differential equations describing thermoelasticity of nonsimple materials in a three-dimensional space. The model of linear dynamical thermoelasticity of nonsimple materials is considered as the system of partial differential equations of fourth order. In this paper, we proposed a convenient evolutionary method of approach to the system of equations of nonsimple thermoelasticity. We proved the Lp−Lq time decay estimates for the solution to the Cauchy problem for linear thermoelasticity of nonsimple materials. 相似文献