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31.
32.
We describe special asymptotic structures of solutions of the semilinear heat equation
33.
K β′-alumina is unstable at >1300°C. Mixed alkali β′-alumina has a variable stability depending on the alkali ratio, [K+]/([Na+]+[K+]). For f(β)<[K+]/([Na+]+[K+]), the β′-Al2O3 phase decomposes to Kβ-Al2O3 0997 0815 V 3 and a solid solution of Na β′-Al2O3 and K β′-Al2O3. For f(β)=[K+]/([Na+]+[K+], the ceramic consists of K β-Al2O3 and Naβ′-Al2O3 and for f(β)>[K+]/([Na+]+[K+]), the excess Na+ after Na β′-Al2O3 dissolves in the β phase, giving Na β-Al2O3/K β-Al2O3 solid solution and Na β′-Al2O3. These sequences were confirmed by measuring the dependence of the c-axis lattice parameters of β- and β′-Al2O3 phases on the f(β), and the change of these parameters during the ion-exchange of Na+ and K+ ions. 相似文献
34.
Shcherbinin S. V. Volchkov S. O. Swindells Ch. Nicholson B. Atkinson D. Kurlyandskaya G. V. 《Russian Physics Journal》2020,63(1):1-8
Russian Physics Journal - The paper presents the calculation results of the coplanar waveguide geometry using the method of conformal mapping and computerized simulation with COMSOL Multiphysics... 相似文献
35.
The behavior of the symmetrical ethane-bridged bis(Zn porphyrin) (1) has been investigated at the air-water interface. The molecular organization of floating films of pure 1 and its mixture with amphiphilic substances, such as arachidic acid and n-octadecylamine, was inspected by means of surface pressure-area isotherms, Brewster angle microscopy and reflection spectroscopy in the UV-Vis region. The overall results suggest the presence in all cases of mainly the anti conformer of 1 even when the dimer was spread on pure water, through the ligation of water molecules to the zinc atoms in the axial positions. It was also demonstrated for the first time that the syn-to-anti conformational transition of the porphyrin dimer can be accelerated by the ligation of suitable amphiphiles even at the liquid-air interface. In particular, it is noted that n-octadecylamine, and arachidic acid (to a lesser extent), added to the system as amphiphiles, drive the syn ? anti equilibrium of 1 towards the anti form through the axial ligation of the amino or carboxylate group to the zinc atoms. 相似文献
36.
37.
The existence of quantum spin liquids was first conjectured by Pomeranchuk some 70 years ago, who argued that frustration in simple antiferromagnetic theories could result in a Fermi-liquid-like state for spinon excitations. Here we show that a simple quantum spin model on a honeycomb lattice hosts the long sought for Bose metal with a clearly identifiable Bose surface. The complete phase diagram of the model is determined via exact diagonalization and is shown to include four distinct phases separated by three quantum phase transitions. 相似文献
38.
Eugueni Kh. Akhmedov Victor V. Berezin 《Zeitschrift fur Physik C Particles and Fields》1992,54(4):661-666
We consider disintegration of deuteron by low energy neutrinos or antineutrinos due to their electromagnetic form factors. Effects of magnetic or electric dipole moments, electric charge radii and anapole moments of neutrinos are taken into account. 相似文献
39.
40.
Let H=1/2+V on l2(B), whereB is the Bethe lattice andV(x),x
B, are i.i.d.r.v.'s with common probability distribution. It is shown that for distributions sufficiently close to the Cauchy distribution, the density of states(E) is analytic in a strip about the real axis. 相似文献