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941.
We suggest theoretically the possibility to transmit information through a decohering quantum channel employing Glauber’s coherent states. In fact, we study the dynamics of quantum correlations of two-mode entangled bipartite coherent states in the presence of the amplitude damping effect. In addition, we examine the quantum correlations based on quantum discord, which is a powerful key source in quantum information processing.  相似文献   
942.
Effective measurement of the reflective or transparent surface of an object has always been a disadvantage in laser scanning modeling. We propose a fast and complete three-dimensional (3D) reconstruction method for small static objects using laser scanning and the structure from motion (SFM) algorithm. Meanwhile, a complete reconstruction workflow is designed and a multi-angle 3d reconstruction system is set up. To generate the complete point cloud model of the object, the SFM algorithm is used to reconstruct the surface part of the object, the data for which cannot be obtained by the laser measuring instrument. The experimental results show that this method not only improves the speed, accuracy, integrity, and visual effect of 3D reconstruction of small objects, but also extends the scope of 3D reconstruction of laser measurement.  相似文献   
943.
We study the small mass limit (or: the Smoluchowski–Kramers limit) of a class of quantum Brownian motions with inhomogeneous damping and diffusion. For Ohmic bath spectral density with a Lorentz–Drude cutoff, we derive the Heisenberg–Langevin equations for the particle’s observables using a quantum stochastic calculus approach. We set the mass of the particle to equal \(m = m_{0} \epsilon \), the reduced Planck constant to equal \(\hbar = \epsilon \) and the cutoff frequency to equal \(\varLambda = E_{\varLambda }/\epsilon \), where \(m_0\) and \(E_{\varLambda }\) are positive constants, so that the particle’s de Broglie wavelength and the largest energy scale of the bath are fixed as \(\epsilon \rightarrow 0\). We study the limit as \(\epsilon \rightarrow 0\) of the rescaled model and derive a limiting equation for the (slow) particle’s position variable. We find that the limiting equation contains several drift correction terms, the quantum noise-induced drifts, including terms of purely quantum nature, with no classical counterparts.  相似文献   
944.
In two papers Franz et al. proved bounds for the free energy of diluted random constraints satisfaction problems, for a Poisson degree distribution (Franz and Leone in J Stat Phys 111(3–4):535–564, 2003) and a general distribution (Franz et al. in J Phys A 36(43), 10967, 2003). Panchenko and Talagrand (Probab Theo Relat Fields 130(3):319–336, 2004) simplified the proof and generalized the result of Franz and Leone (J Stat Phys 111(3–4):535–564, 2003) for the Poisson case. We provide a new proof for the general degree distribution case and as a corollary, we obtain new bounds for the size of the largest independent set (also known as hard core model) in a large random regular graph. Our proof uses a combinatorial interpolation based on biased random walks (Salez in Combin Probab Comput 25(03):436–447, 2016) and allows to bypass the arguments in Franz et al. (J Phys A 36(43):10967, 2003) based on the study of the Sherrington–Kirkpatrick (SK) model.  相似文献   
945.
We study a spatial birth-and-death process on the phase space of locally finite configurations \({\varGamma }^+ \times {\varGamma }^-\) over \({\mathbb {R}}^d\). Dynamics is described by an non-equilibrium evolution of states obtained from the Fokker-Planck equation and associated with the Markov operator \(L^+(\gamma ^-) + \frac{1}{\varepsilon }L^-\), \(\varepsilon > 0\). Here \(L^-\) describes the environment process on \({\varGamma }^-\) and \(L^+(\gamma ^-)\) describes the system process on \({\varGamma }^+\), where \(\gamma ^-\) indicates that the corresponding birth-and-death rates depend on another locally finite configuration \(\gamma ^- \in {\varGamma }^-\). We prove that, for a certain class of birth-and-death rates, the corresponding Fokker-Planck equation is well-posed, i.e. there exists a unique evolution of states \(\mu _t^{\varepsilon }\) on \({\varGamma }^+ \times {\varGamma }^-\). Moreover, we give a sufficient condition such that the environment is ergodic with exponential rate. Let \(\mu _{\mathrm {inv}}\) be the invariant measure for the environment process on \({\varGamma }^-\). In the main part of this work we establish the stochastic averaging principle, i.e. we prove that the marginal of \(\mu _t^{\varepsilon }\) onto \({\varGamma }^+\) converges weakly to an evolution of states on \({\varGamma }^+\) associated with the averaged Markov birth-and-death operator \({\overline{L}} = \int _{{\varGamma }^-}L^+(\gamma ^-)d \mu _{\mathrm {inv}}(\gamma ^-)\).  相似文献   
946.
Linear motion of a rigid body in a special kind of Lorentz gas is mathematically analyzed. The rigid body moves against gas drag according to Newton’s equation. The gas model is a special Lorentz gas consisting of gas molecules and background obstacles, which was introduced in Tsuji and Aoki (J Stat Phys 146:620–645, 2012). The specular boundary condition is imposed on the resulting kinetic equation. This study complements the numerical study by Tsuji and Aoki cited above—although the setting in this paper is slightly different from theirs, qualitatively the same asymptotic behavior is proved: The velocity V(t) of the rigid body decays exponentially if the obstacles undergo thermal motion; if the obstacles are motionless, then the velocity V(t) decays algebraically with a rate \(t^{-\,5}\) independent of the spatial dimension. This demonstrates the idea that interaction of the molecules with the background obstacles destroys the memory effect due to recollision.  相似文献   
947.
MMP-12 belongs to a large family of proteases called matrix metalloproteinases (MMPs) that degrades elastin. The main pathologic role of MMP-12 overexpression was suggested to be associated with pathogenesis mechanism of inflammatory respiratory diseases and atherosclerosis. An integrated ligand- and structure-based virtual screening was employed in hope of finding inhibitors with new scaffolds and selectivity for MMP-12. Seven compounds among 18 experimentally tested compounds had a measurable effect on the inhibition of MMP-12 enzyme. Our results demonstrated the applicability of the developed pharmacophore model and selected crystal structure (PDB code: 3F17) to discover new MMP-12 inhibitors. The receptor structure was selected based on cross-docking results. Here, we report the discovery of new class of MMP-12 inhibitors that could be used for lead optimization. For the inhibition of MMP-12, the significance of its interactions with the catalytic residues Glu219 and Ala182 was emphasized through the inspection of the docking poses.  相似文献   
948.
Rapid, efficient, simple and green procedure for the synthesis of 4,5-dihydro-1H-pyrazole-1-carbothioamides via the multicomponent reaction of aryl aldehydes, acetophenones and thiosemicarbazide in water in the presence of tetrabutylammonium hydroxide under microwave irradiation is reported.  相似文献   
949.
950.
As two-dimensional layered nanomaterials, the tungsten disulfide (WS2) nanosheets can be used as building blocks of paper-like electrodes for high-performance FSs. However, poor conductivity and mechanical property of WS2 nanosheets (NSs) paper greatly hinders their capacitance and/or rate performance. To solve these problems, we fabricated the WS2-multiwalled carbon nanotubes (MWCNTs)/polyaniline (PANI) composite papers based on liquid exfoliation and electrochemical deposition for high-performance flexible supercapacitors. The WS2-MWCNTs/PANI with conductive PANI chains linked WS2 NSs and MWCNTs takes the advantages of high-electronic double-layer capacitance originated from the internal surface areas of MWCNTs and effective pseudocapacitance generated by exfoliated WS2 NSs and PANI. Electrochemical studies showed that the gravimetric-specific capacitance of WS2-MWCNTs/PANI can reach ~760.1 F/g at a current density of 1 A/g. A symmetric flexible solid-state supercapacitor was also assembled and studied. The WS2-MWCNTs/PANI-assembled FS device also has an excellent area specific capacitance of 1158.7 mF/cm2 at a current density of 0.5 mA/cm2 together with a high-capacity retention of ~82.5% after 2000 cycles.  相似文献   
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