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991.
《Nuclear Physics B》1996,466(3):499-512
We derive an exact expression for the single-particle Green function in the Calogero-Sutherland model for all the rational values of the coupling β. The calculation is based on Jack polynomial techniques and the results are given in the thermodynamical limit. Two types of intermediate states contribute. The first one consists of a particle propagating out of the Fermi sea and the second one consists of a particle propagating in one direction, q particles in the opposite direction and p holes.  相似文献   
992.
《Nuclear Physics B》1996,472(3):495-517
We consider the implications of solar matter density random noise upon resonant neutrino conversion. The evolution equation describing MSW-like conversion is derived in the framework of the Schrödinger approach. We study quantitatively the effect of such matter perturbations upon both large and small mixing angle MSW solutions to the solar neutrino problem. This is carried out both for the active-active vevμ,τ as well as active-sterile vevs conversion channels. We find that the small mixing MSW solution is much more stable (especially in Δm2 than the large mixing solution. The possible existence of solar matter density noise at the few percent level could be tested at future solar neutrino experiments, especially Borexino.  相似文献   
993.
994.
《Physica A》1996,231(4):425-438
The smooth-particle weighting functions used in numerical solutions of the thermomechanical continuum equations can be interpreted as weak pair potentials from the standpoint of statistical physics. We examine both equilibrium and nonequilibrium thermomechanical properties of many-body systems using a typical smooth particle potential, Lucy's, and discuss the implications for macroscopic continuum simulations.  相似文献   
995.
《Nuclear Physics B》1996,477(2):378-406
We propose a semiclassical approach to calculate multiparticle cross sections in scalar theories, which have been strongly argued to have the exponential form exp(λ−1 F(λn, ϵ)) in the regime λ → 0, λn, ϵ = fixed, where λ is the scalar coupling, n is the number of produced particles, and ϵ is the kinetic energy per final particle. The formalism is based on singular solutions to the field equation, which satisfy certain boundary and extremizing conditions. At low multiplicities and small kinetic energies per final particle we reproduce in the framework of this formalism the main perturbative results. We also obtain a lower bound on the tree-level cross section in the ultra-relativistic regime.  相似文献   
996.
We measured MR images of the liver of Long-Evans Cinnamon (LEC) rats with pathologic correlation and assessed the effectiveness of MR imaging (MRI) for diagnosis of noncancerous hepatic lesions. T1- and T2-weighted images of their livers were obtained, and the dynamic and delayed studies after intravenous gadolinium injection were also performed. Cholangiofibrosis showed low signal intensity on T1-weighted images and high signal intensity on T2-weighted images. The T2 relaxation time of cholangiofibrosis was significantly prolonged (p < .01), and the signal intensity ratio of this lesion to muscle on T1-weighted images was significantly lower than that of normal liver parenchyma to muscle (p < .01). The lesion was enhanced immediately after gadolinium injection and the enhancement was prolonged. Among three cases of peliosis hepatis identified, one showed heterogeneous intensities on both T1- and T2-weighted images and the other two showed similar intensity pattern to cholangiofibrosis. The characteristic MR appearance of cholangiofibrosis may be useful to distinguish it from hepatocellular carcinoma (HCC).  相似文献   
997.

Quantum proxy signature(QPS) is one of the most important topics in quantum signature. In this paper, we propose a new and general model of QPS based on genuine entangled Nj-qubit (3 ≤ Nj ≤ 6,NjN,j = 1,2,3,4.) states. In our model, only the teleportation of multiparty entangled states and quantum one-time pad(QOTP) encryption algorithm have been applied to ensure the security. We hope our results will be helpful to the research of quantum signature in future.

  相似文献   
998.
《Opto-Electronics Review》2019,27(2):105-112
There is a high impact of the solar cells on energy manufacturing. For several years the energy efficiency was limited due to base-materials' structural and technological limits. High increase of energy harvesting of solar cells has been observed since the first solar cell based on dye-sensitized colloidal TiO2 films occurred. One of the most promising solutions are used quantum dots (QD) for light energy conversion. In this paper, we described the use of selected characterization techniques for sandwich-type TiO2/QD composites for a low-cost quantum dots' solar cell in the point of view of mass manufacturer of solar cells and research and development laboratory. Moreover, the increasing role of Raman spectroscopy and mapping for the TiO2/QD was presented and compared with other necessity techniques for solar cell investigations such as ellipsometry, atomic force microscopy (AFM), and secondary ion mass spectrometry (SIMS).  相似文献   
999.

This paper is concerned with the better security of quantum image secret sharing (QISS) algorithm. The improved QISS (IQISS) scheme is implemented on both quantum gray image (FRQI) and quantum color image (MCQI). The new IQISS scheme comprises efficient sharing process and recovering process. The core idea of the sharing process is to combine encryption and measurement for two types of quantum secret images to acquire the quantum shadow images. In the recovering process, strip operation is firstly utilized on the shadow images. Afterwards, the decryption algorithm is used to recover the original quantum secret image. Experiments demonstrate that significant improvements in the security are in favor of the proposed approach.

  相似文献   
1000.
The present work is a theoretical study of the electronic properties of alloyed double metal ring (ADMR) threaded by magnetic flux. The studied system is consisting of two rings connected parallel, with two different types of atomic sites. This work contains two parts. First is an analytical study of calculation of the energy spectrum, persistent current, Drude weight and low-field magnetic susceptibility of ADMR by the tight-binding method. Second is a computation study of electronic properties of the alloyed double metal ring by density functional theory (DFT). The latter part is considered as a complementary study of what was studied in the first part in order to determine the best materials which will be used to design alloyed double metal ring. Our results show that the on-site energies for both types of atoms, inter-ring coupling strength and hopping strengths play an interesting role in controlling the electronic properties.  相似文献   
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