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991.
The results of calculation of radiation-defect distribution profiles and thermal-mechanical characteristics under the action of powerful laser beams on semiconductor MCT samples are reported. The calculations were performed within the physical-mathematical model of radiation defect formation. The calculated profiles are compared with the theoretical and experimental data.  相似文献   
992.
The evolution of quantum coherences comes with a set of conservation laws provided that the Hamiltonian governing this evolution conserves the spin-excitation number. At that, coherences do not intertwist during the evolution. Using the transmission line and the receiver in the initial ground state we can transfer the coherences to the receiver without interaction between them, although the matrix elements contributing to each particular coherence intertwist in the receiver’s state. Therefore we propose a tool based on the unitary transformation at the receiver side to untwist these elements and thus restore (at least partially) the structure of the sender’s initial density matrix. A communication line with two-qubit sender and receiver is considered as an example of implementation of this technique.  相似文献   
993.
We characterize Banach lattices on which each positive operators is b-weakly compact and we derive some characterizations of KB-spaces.  相似文献   
994.
We consider boundary value problems in a half-space for a class of quasi-elliptic systems with constant coefficients. We assume that the boundary value problems satisfy the Lopatinskii condition. We obtain necessary and sufficient conditions for their unique solvability in Sobolev spaces.  相似文献   
995.
For the first time, a manifold of symmetric real matrices with fixed multiplicities of eigenvalues was considered by Arnold. In the case of compact real self-adjoint operators, similar results were obtained by Japanese mathematicians Fujiwara, Tanikawa, and Yukita. They introduced a special local diffeomorphism “straightening” the Arnold manifold. Later, the properties of the indicated diffeomorphism were studied by Dymarskii. We describe the smooth structure of submanifolds of finite-dimensional and compact operators of the general form in which a selected eigenvalue is associated with a single Jordan block.  相似文献   
996.
Sloshing of fluids with a free surface contained in liquid storage tanks is numerically simulated by an arbitrary Lagrangian-Eulerian formulation. The fluid is considered viscous and Newtonian, while the flow is assumed laminar and incompressible. A partitioned and distributed computational code is employed, which solves three instances each time step: (i) the determination of the fluid state, given by the Navier–Stokes equations; (ii) the displacement of the free surface; and (iii) the update of the position of the internal nodes of the mesh, that is deformed as a consequence of the free surface displacement. The purpose of the work is verifying the applicability of the method to sloshing problems with known solutions, as well as the resolution of some practical examples. Numerical examples include validations against analytical solutions, where the wave period and damping rate are well captured, comparisons with reference results from other authors and a sample of sloshing induced by seismic actions.  相似文献   
997.
New normal forms are obtained for the center as well as isochronous center of holomorphic Liénard systems.  相似文献   
998.
Kinetics of the reaction of aquacobalamin (H2OCbl) with isoniazid (isonicotinic acid hydrazide, INH) in weakly alkaline, neutral, and weakly acidic media was studied using UV–Vis spectroscopy. It is shown that the reversible formation of a complex more stable than those of cobalamin(III) with pyridine and hydrazine occurs during the reaction. A mechanism of the reaction includes reversible stages of binding a neutral INH molecule by cobalamin(III) through an oxygen atom with its subsequent deprotonation, along with the reversible interaction of H2OCbl and the negatively charged form of INH.  相似文献   
999.
The fixation and activation of molecular oxygen on copper(II) complexes with 5-hydroxy and 5-aminoorotic acids, leading to oxidation of the ligand.  相似文献   
1000.
Russian Journal of Organic Chemistry - New 1-(ω-chloroalkyl)isatins were synthesized by alkylation of isatin with α-bromo-ω-chloroalkanes. The reaction of 1-(3-chloropropyl)isatin...  相似文献   
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