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11.
The general analysis of the rare Bc→Ds
*ℓ+ℓ- decay is presented by using the most general, model independent effective Hamiltonian. The dependencies of the branching
ratios and of the longitudinal, normal and transversal polarization asymmetries for ℓ- and the combined asymmetries for ℓ- and ℓ+ on the new Wilson coefficients are investigated. Our analysis shows that the lepton polarization asymmetries are very sensitive
to the scalar and tensor type interactions, which will be very useful in looking for new physics beyond the standard model. 相似文献
12.
F. Betül Kaynak Süheyla
zbey Turan
ztürk Erdal Erta 《Acta Crystallographica. Section C, Structural Chemistry》2001,57(9):1125-1126
The title compound, C17H10S4, has two independent molecules in the asymmetric unit. In both molecules, the fused heterocycle is almost planar and the phenyl groups make dihedral angles of 42.88 (9) and 52.79 (8)° with the fused heterocycle in one molecule, and angles of 40.62 (9) and 52.28 (8)° in the other. The crystal packing is governed by short intermolecular S?S interactions, the shortest contact being 3.333 (1) Å. 相似文献
13.
N,N′‐Diiodo‐N,N′‐1,2‐ethandiylbis(p‐toluene sulfonamide) (NIBTS) is a good and new reagent for synthesis of 2‐arylbenzimidazoles and 2‐arylbenzothiazoles at room temperature under solvent‐free condition with good to high yield. Absence of solvent, short reaction times, non‐corrosive, operational simplicity and environmentally friendliness are the main advantages of this procedure. 相似文献
14.
In this article, both the eigenvectors and the eigenvalues of the q‐Bernstein operators have been studied. Explicit formulae are presented for the eigenvectors, whose limit behavior is determined both in the case 0 < q < 1 and in the case q > 1. Because the classical case, where q = 1, was investigated exhaustively by S. Cooper and S. Waldron back in 2000, the present article also discusses the related similarities and distinctions with the results in the classical case. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
15.
In this paper, we model and solve profit maximization problem of a telecommunications Bandwidth Broker (BB) under uncertain market and network infrastructure conditions. The BB may lease network capacity from a set of Backbone Providers (BPs) or from other BBs in order to gain profit by leasing already purchased capacity to end-users. BB’s problem becomes harder to deal with when bandwidth requests of end-users, profit and cost margins are not known in advance. The novelty of the proposed work is the development of a mechanism via combining fuzzy and stochastic programming methodologies for solving complex BP selection and bandwidth demand allocation problem in communication networks, based on the fact that information needed for making these decisions is not available prior to leasing capacity. In addition, suggested model aims to maximize BB’s decision maker’s satisfaction ratio rather than just profit. As a solution strategy, the resulting fuzzy stochastic programming model is transformed into deterministic crisp equivalent form and then solved to optimality. Finally, the numerical experiments show that on the average, proposed approach provides 14.30% more profit and 69.50% more satisfaction ratio compared to deterministic approaches in which randomness and vagueness in the market and infrastructure are ignored. 相似文献
16.
Loss of stability of a simply supported strip with two parallel cracks is analyzed within the framework of the three-dimensional
linearized theory of stability of deformable bodies with finite precritical strains. The corresponding eigenvalue problem
is solved by the finite-element method. It is supposed that the strip material is isotropic, homogeneous, compressible, and
hyperelastic, and its elasticity relations are expressed in terms of a harmonic potential. Numerical critical values of the
elongation of the strip obtained for different values of problem parameters are presented 相似文献
17.
A liquid sloshing absorber consists of a container, partially filled with liquid. The absorber is attached to the structure to be controlled, and relies on the structure’s motion to excite the liquid. Consequently, a sloshing wave is produced at the liquid free surface within the absorber, possessing energy dissipative qualities. The behaviour of liquid sloshing absorbers has been well documented, although their use in structural control applications has attracted considerably less attention. 相似文献
18.
19.
Adam Marsh Mahesh Prakash Eren Semercigil Özden F. Turan 《Journal of Fluids and Structures》2011,27(8):1165-1181
A liquid sloshing absorber consists of a container, partially filled with liquid. The absorber is attached to the structure to be controlled, and relies on the structure's motion to excite the liquid. Consequently, a sloshing wave is produced at the liquid free-surface within the absorber, possessing energy dissipative qualities. The primary objective of this work is to numerically demonstrate the effect of a sloshing absorber's shape on its control performance. Smoothed Particle Hydrodynamics (SPH) is used to model fluid–structure interaction of the structure/sloshing absorber system in two dimensions. The structure to be controlled is a lightly damped single degree-of-freedom structure. The structure is subjected to a transient excitation and then allowed to respond dynamically, coming to rest either due to its own damping alone or with the added control of the sloshing absorber. It is identified that the control performance of the conventionally used rectangular container geometry can be improved by having inward-angled walls. This new arrangement is robust, and of significant advantage in situations when the external disturbance is of uncertain magnitude. 相似文献
20.
Aybüke A. İsbir Turan Zafer Üstündağ Ali Osman Solak Emine Kılıç Ayça Avseven 《Electroanalysis》2008,20(15):1665-1670
This work describes the characterization of the grafted 2‐benzo[c]cinnoline (2BCC) molecules at a glassy carbon (GC) electrode surface by voltammetry and spectroscopy. Attachment of the molecule to the carbon substrate was achieved by the electrochemical reduction of 2‐benzo[c]cinnoline diazonium salt (2BCC‐DAS). GC electrode modification was carried out in aprotic solution with 2BCC diazonium salt. Dopamine (DA) and ascorbic acid (AA) were used to prove the surface modification to see the blockage of the electron transfer. The presence of 2BCC at the GC electrode surface was characterized by cyclic voltammetry and Raman spectroscopy. Raman spectroscopy was used to monitor molecular bound properties of the adsorbates at the 2BCC‐GC surface and confirm the attachment of 2BCC molecules onto the GC surface. The thickness of the 2BCC film on GC was also investigated by ellipsometric measurement. 相似文献