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131.
E. A. Popova N. Tristan A. N. Vasiliev V. L. Temerov L. N. Bezmaternykh N. Leps B. Büchner R. Klingeler 《The European Physical Journal B - Condensed Matter and Complex Systems》2008,62(2):123-128
We present thermodynamic and magnetic studies of single crystalline DyFe3(BO3)4. The data indicate an easy axis antiferromagnetic order below TN~ 38 K which we attribute to the Fe subsystem. The Dy subsystem remains paramagnetic down to the lowest investigated temperatures
of 2 K, but it is polarized by the Fe spins due to a f-d interaction. External magnetic field leads to a spin-flop transition
in the iron subsystem as well as to superposed magnetization in the Dy subsystem. The repopulation of two low-lying Kramers
doublets in Dy3+ ions results in well defined Schottky anomalies in specific heat and magnetization. 相似文献
132.
A. V. Vasiliev 《Journal of Applied and Industrial Mathematics》2008,2(4):585-590
D. M. Barrington proved the coincidence of the class NC1 of functions computable by the circuits of logarithmic depth with the class of functions computable by branching programs of constant width and polynomial length (BWBP). In this paper, the structure of branching programs suggested by the Barrington method is defined more exactly. Namely, it is proved that we can compute all functions from NC1 and only them by the k-OBDDs of polynomial size and width 5. This can be reformulated as poly(n)-OBDD5 =NC1. 相似文献
133.
We consider the totally asymmetric simple exclusion process, a model in the KPZ universality class. We focus on the fluctuations of particle positions, starting with certain deterministic initial conditions. For large time t, one has regions with constant and linearly decreasing density. The fluctuations on these two regions are given by the Airy1 and Airy2 processes, whose one‐point distributions are the GOE and GUE Tracy‐Widom distributions of random matrix theory. In this paper we analyze the transition region between these two regimes and obtain the transition process. Its one‐point distribution is a new interpolation between GOE and GUE edge distributions. © 2007 Wiley Periodicals, Inc. 相似文献
134.
Alexander Balakin Heinz Dehnen Alexei Zayats 《General Relativity and Gravitation》2008,40(12):2493-2513
Non-minimal interactions in the pp-wave Einstein–Yang–Mills–Higgs (EYMH) model are shown to give rise to color cross-effects
analogous to the magneto-electricity in the Maxwell theory. In order to illustrate the significance of these color cross-effects,
we reconstruct the effective (associated, color, and color-acoustic) metrics for the pp-wave non-minimal seven-parameter EYMH
model with parallel gauge and scalar background fields. Then these metrics are used as hints for obtaining explicit exact
solutions of the non-minimally extended Yang–Mills and Higgs equations for the test fields propagating in the vacuum interacting
with curvature. The influence of the non-minimal coupling on the test particle motion is interpreted in terms of the so-called
trapped surfaces, introduced in the Analog Gravity theory. 相似文献
135.
Alexei V. Radchenko Sergei V. Kostjuk Irina V. Vasilenko François Ganachaud Fyodor N. Kaputsky Yohann Guillaneuf 《Journal of polymer science. Part A, Polymer chemistry》2008,46(20):6928-6939
A kinetic study of the living cationic polymerization of p‐methoxystyrene using 1‐(4‐methoxyphenyl)ethanol ( 1 )/B(C6F5)3 initiating system in a mixture of CH3CN with CH2Cl2 1:1 (v/v) at room temperature was carried out utilizing a wide variety of conditions. The polymerization proceeded in a living fashion even in the presence of a large amount of water ([H2O]/[B(C6F5)3] ratio up to 20) to afford polymers whose Mn increased in direct proportion to monomer conversion with fairly narrow MWDs (Mw/Mn ≤ 1.3). The investigation revealed that the rate of polymerization was first‐order in B(C6F5)3 concentration, while a negative order in H2O concentration close to ?2 was obtained. It was also found that the rate of polymerization decreased with lowering temperature, which could be attributed to a decreased concentration in free Lewis acid, the true coinitiator of polymerization. A mechanistic scheme to explain the kinetic behavior of living p‐methoxystyrene polymerization is proposed, which has been validated by PREDICI simulation on multiple‐data curves obtained by 1H NMR in situ polymerization experiment. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 6928–6939, 2008 相似文献
136.
137.
T. E. Kokina L. A. Glinskaya E. S. Vasiliev M. I. Rakhmanova S. V. Makarova D. A. Piryazev I. V. Korol’kov A. V. Tkachev S. V. Larionov 《Journal of Structural Chemistry》2017,58(5):994-1003
Complexes ZnLCl2 (I) and [CdLCl2] n (IV), where L is chiral bis-pyridine containing fragments of natural monoterpenoide (–)-α-pinene are synthesized. Single crystals of [ZnLCl2]·CH2Cl2 (II), [ZnLCl2]·i-PrOH (III), and IV compounds are grown. The crystal structures of II and III are composed of mononuclear ZnLCl2 complex molecules and solvate CH2Cl2 and i-PrOH molecules; the coordination polyhedron of the zinc atom Cl2N2 is a distorted tetrahedron. According to the single crystal XRD data, complex IV is a 1D coordination polymer; the coordination core CdN2Cl4 is a distorted octahedron and Cl atoms are bridging ligands. In the structures of II, III, and IV the L molecule functions as a bidentate chelate ligand. In the solid phase, complexes I and IV exhibit photoluminescence in the visible range (λmax 505 nm and 460 nm respectively). The band intensity in the photoluminescence spectra of I and IV complexes considerably exceeds the band intensity in the spectrum of free L. 相似文献
138.
139.
It is reported that S-glycosyl O-methyl phenylcarbamothioates (SNea carbamothioates) have a fully orthogonal character in comparison to S-benzoxazolyl (SBox) glycosides. This complete orthogonality was revealed by performing competitive glycosylation experiments in the presence of various promoters. The results obtained indicate that SNea carbamothioates have a very similar reactivity profile to that of glycosyl thiocyanates, yet are significantly more stable and tolerate selected protecting group manipulations. These features make the SNea carbamothioates new promising building blocks for further utilization in oligosaccharide synthesis. 相似文献
140.
Sergey V. Korkin Alexei I. Lyapustin 《Journal of Quantitative Spectroscopy & Radiative Transfer》2011,112(10):1595-1608
This paper considers a scalar radiative transfer problem with high scattering anisotropy. Two computational methods are presented based on decomposition of the diffuse light field into a regular and anisotropic part. The first algorithm (DOMAS) singles out the anisotropic radiance in the forward scattering peak using the Small-Angle Modification of RTE. The second algorithm (DOM2+) separates the single scattering radiance as an anisotropic part, which largely defines the fine detail of the total radiance in the backscattering directions. In both cases, the anisotropic part is represented analytically. With anisotropy subtraction, the regular part of the signal, which requires a numerical solution, is essentially smoothed as a function of angles. Further, the transport equation is obtained for the regular part that contains an additional source function from the anisotropic part of the signal. This equation is solved with the discrete ordinates method. A conducted numerical analysis of this work showed that algorithm DOMAS has a strong advantage as compared to the standard discrete ordinates method for simulation of the radiance transmission, and DOM2+ is the best of the three for the reflection computations. Both algorithms offer at least a factor of three acceleration of convergence of the azimuthal series for highly anisotropic phase functions. 相似文献