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11.
In the present paper, we consider non-linear Markov operators, namely polynomial stochastic operators. We introduce a notion of orthogonal preserving polynomial stochastic operators. The purpose of this study is to show that surjectivity of non-linear Markov operators is equivalent to their orthogonal preserving property.  相似文献   
12.
In this paper an analog of the Blum-Hanson theorem for quantum quadratic processes on the von Neumann algebra is proved, i.e., it is established that the following conditions are equivalent:
i)  P( t )x is weakly convergent tox 0;
ii)  for any sequence {a n} of nonnegative integrable functions on [1, ∞) such that ∝ 1 a n(t)dt=1 for anyn and lim n→∞a n=0, the integral ∝ 1 a n(t)P( t )x dt is strongly convergent tox 0 inL 2(M, ϕ), wherex ɛM,P( t ) is a quantum quadratic process,M is a von Neumann algebra, andϕ is an exact normal state onM.
Translated fromMatematicheskie Zametki, Vol. 67, No. 1, pp. 102–109, January, 2000.  相似文献   
13.
The crystal structure of α-(N-benzoxazoline-2-one) acetic acid is studied in the following forms: hydrate, solvate with formic acid, organic monoethanolammonium salt (NН2(CH2)2OH) in two polymorphs produced by minor changes in the crystallization temperature, and also its ethylenediammonium salt (NН2(CH2)2NH2) in the 2:1 ratio, where amino groups participate in the deprotonation of two molecules of α-(N-benzoxazoline-2-one) acetic acid. Weak intermolecular hydrogen and dative bonds in the crystals consisting of different molecules are analyzed.  相似文献   
14.
The corresponding 6-chlorosulfonyl derivatives were synthesized from benzoxazolin-2-one and its 3-methyl derivative by treatment with chlorosulfonic acid. By treatment of the compounds obtained with water and other nucleophilic reagents (aliphatic and heterocyclic amines) 2-oxobenzoxazoline-6-sulfonic acids and a series of their amides were obtained, while reduction with SnCl2·2H2O gave 6-mercaptobenzoxazolin-2-ones.  相似文献   
15.
Two crystalline polymorphic forms of α-(N-benzoxazolin-2-one)acetic acid (BAA) are prepared by changing the temperature of its crystallization from solution in ethanol. Crystallographic data of the α-form are determined: a = 12.7769(17) Å, b = 8.2574(9) Å, c = 16.7390(19) Å, β = 105.087(13)°, space group C2/c, V = 1705.2(4) Å3, and Z = 8, while those of β form are a = 5.2854(4) Å, b = 5.9880(4) Å, c = 13.4509(5) Å, β = 94.666(4)°, space group P21, V = 424.30(4) Å3, and Z = 2. It is found that BAA molecules of the α form combine into infinite one-dimensional chains arranged along axis b by means of O?H···O and C?H···O hydrogen bonds, and these chains are crosslinked via C?H···O hydrogen bonds to form a threedimensional structure. The β form has another system of hydrogen bonds, one of which is bifurcated (O4···O2, O4···O3), and the π–π-interactions between the benzoxazolinone fragments of BAA molecules combined into a chain also arranged along axis b are observed. Calorimetric analysis shows that the polymorphic transition from the α form to the β form occurs at 129°C.  相似文献   
16.
4-Butyl-4-hydroxydeoxypeganine was prepared by lithiation of deoxyvasicinone. Deoxypeganine and 1,2-dihydrodeoxypeganine were produced by reduction of deoxyvasicinone with lithium aluminum hydride.  相似文献   
17.
We present necessary and sufficient conditions for the validity of a regularity condition for homogeneous quantum quadratic stochastic processes defined on von Neumann algebras.  相似文献   
18.
We consider the λ model, a generalization of the Potts model, with spin values {1, 2, 3} on the order-two Cayley tree. We describe the model ground states and prove that translation-invariant Gibb measures exist, which means that a phase transition exists. We establish that two-periodic Gibbs measures exist.  相似文献   
19.
We study a phase transition problem for the q-state p-adic Potts model on the Cayley tree of order three. We find certain conditions for the existence of p-adic Gibbs measures and then establish the existence of a phase transition.  相似文献   
20.
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