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91.
92.
93.
Let ?∞ be the space of all bounded sequences x=(x1,x2,…) with the norm
94.
We prove that a real function is operator monotone (operator convex) if the corresponding monotonicity (convexity) inequalities
are valid for some normal state on the algebra of all bounded operators in an infinite-dimensional Hilbert space. We describe
the class of convex operator functions with respect to a given von Neumann algebra in dependence of types of direct summands
in this algebra. We prove that if a function from ℝ+ into ℝ+ is monotone with respect to a von Neumann algebra, then it is also operator monotone in the sense of the natural order on
the set of positive self-adjoint operators affiliated with this algebra. 相似文献
95.
For a field F and a family of central simple F-algebras we prove that there exists a regular field extension E/F preserving indices of F-algebras such that all the algebras from the family are cyclic after scalar extension by E. Let \( \mathcal{A} \) be a central simple algebra over a field F of degree n with a primitive nth root of unity ρ n . We construct a quasi-affine F-variety Symb(\( \mathcal{A} \)) such that for a field extension L/F Symb(\( \mathcal{A} \)) has an L-rational point if and only if \( \mathcal{A}{ \otimes_F}L \) is a symbol algebra. Let \( \mathcal{A} \) be a central simple algebra over a field F of degree n and K/F be a cyclic field extension of degree n. We construct a quasi-affine F-variety C(\( \mathcal{A} \) ,K) such that, for a field extension L/F with the property [KL : L] = [K : F], the variety C(\( \mathcal{A} \) ,K) has an L-rational point if and only if KL is a subfield of \( \mathcal{A}{ \otimes_F}L \). 相似文献
96.
Evgenii Titov 《Molecules (Basel, Switzerland)》2021,26(14)
Azobenzene-containing molecules may associate with each other in systems such as self-assembled monolayers or micelles. The interaction between azobenzene units leads to a formation of exciton states in these molecular assemblies. Apart from local excitations of monomers, the electronic transitions to the exciton states may involve charge transfer excitations. Here, we perform quantum chemical calculations and apply transition density matrix analysis to quantify local and charge transfer contributions to the lowest electronic transitions in azobenzene dimers of various arrangements. We find that the transitions to the lowest exciton states of the considered dimers are dominated by local excitations, but charge transfer contributions become sizable for some of the lowest electronic transitions in stacked and slip-stacked dimers at short intermolecular distances. In addition, we assess different ways to partition the transition density matrix between fragments. In particular, we find that the inclusion of the atomic orbital overlap has a pronounced effect on quantifying charge transfer contributions if a large basis set is used. 相似文献
97.
We prove Pitt and Boas inequalities for products of radial functions and spherical harmonics in Rn. In the process, we obtain upper and lower estimates of the operator norm of the Hankel transform with power weights. Our inequalities are sharp in some specific cases. 相似文献
98.
M. A. Gusarova R. A. Kostin M. V. Lalayan E. A. Savin N. P. Sobenin D. B. Tikhonov 《Technical Physics》2013,58(4):601-607
The temperature distribution in the accelerating structures of standing-wave and traveling-wave electron linacs is calculated. The objects of consideration in the former and latter cases are, respectively, a circular iris waveguide with magnetic coupling and a biperiodic accelerating structure. Calculation data for steady and transient heating conditions are presented. The variation of the cell’s geometry and resonance frequency with the temperature of the structure is also calculated. Calculations are made for copper structures with allowance for microwave wall losses. 相似文献
99.
P. O. Kapralov V. G. Artemov G. A. Gusev V. I. Tikhonov A. A. Volkov 《Bulletin of the Russian Academy of Sciences: Physics》2008,72(12):1679-1683
The diffusion of water vapor into porous polymer adsorbent MN-200 has been investigated by diode laser spectroscopy with a time resolution of 0.1 s. The cascade character of diffusion, caused presumably by the fractality of the porous matrix space, is established by decomposition analysis. The collisionless (Knudsen) mode of water motion in pores, in which water molecules can be sorted according to their spin states, is selected. 相似文献
100.