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151.
Simple Entanglement Measure for Multipartite Pure States 总被引:3,自引:0,他引:3
Feng Pan Feng Pan Feng Pan Dan Liu Guoying Lu J. P. Draayer 《International Journal of Theoretical Physics》2004,43(5):1241-1247
A simple entanglement measure for multipartite pure states is formulated based on the partial entropy of a series of reduced density matrices. Use of the proposed new measure to distinguish disentangled, partially entangled, and maximally entangled multipartite pure states is illustrated. 相似文献
152.
Dependence of bimodal size distribution on temperature and optical properties of InAs quantum dots grown on vicinal GaAs (100) substrates by using MOCVD 下载免费PDF全文
Self-assembled InAs quantum dots (QDs) are grown on vicinal GaAs (100)
substrates by using metal-organic chemical vapour deposition (MOCVD). An
abnormal temperature dependence of bimodal size distribution of InAs quantum
dots is found. As the temperature increases, the density of the small dots
grows larger while the density of the large dots turns smaller, which is
contrary to the evolution of QDs on exact GaAs (100) substrates. This trend
is explained by taking into account the presence of multiatomic steps on the
substrates. The optical properties of InAs QDs on vicinal GaAs(100)
substrates are also studied by photoluminescence (PL) . It is found that
dots on a vicinal substrate have a longer emission wavelength, a narrower PL
line width and a much larger PL intensity. 相似文献
153.
We study some typical defect problems in one-dimensional (1D) hexagonal and two-dimensional (2D) octagonal quasicrystals.
The first part of this investigation addresses in detail a uniformly moving screw dislocation in a 1D hexagonal piezoelectric
quasicrystal with point group 6mm. A general solution is derived in terms of two functions φ
1, φ
2, which satisfy wave equations, and another harmonic function φ
3. Elementary expressions for the phonon and phason displacements, strains, stresses, electric potential, electric fields and
electric displacements induced by the moving screw dislocation are then arrived at by employing the obtained general solution.
The derived solution is verified by comparison with existing solutions. Also obtained in this part of the investigation is
the total energy of the moving screw dislocation. The second part of this investigation is devoted to the study of the interaction
of a straight dislocation with a semi-infinite crack in an octagonal quasicrystal. Here the crack penetrates through the solid
along the period direction and the dislocation line is parallel to the period direction. We first derive a general solution
in terms of four analytic functions for plane strain problem in octagonal quasicrystals by means of differential operator
theory and the complex variable method. All the phonon and phason displacements and stresses can be expressed in terms of
the four analytic functions. Then we derive the exact solution for a straight dislocation near a semi-infinite crack in an
octagonal quasicrystal, and also present the phonon and phason stress intensity factors induced by the straight dislocation
and remote loads.
相似文献
154.
Sonodynamic therapy (SDT) is a novel tumor therapy method. We investigated membrane fluidity, activity of the enzymes and membrane morphology in vitro post hematoporphyrin-SDT treatment. Furthermore, the potential mechanisms behind the changes in membrane fluidity and enzymic activity were discussed. Tumor cells were exposed to ultrasound at 1.75 MHz for up to 3 min in the presence and absence of hematoporphyrin. Fluorescence polarization, contents of Malonaldehyde, and levels of free fatty acid were assessed. Activity of enzymes was checked by the plumbic nitrate detection method. For the morphologic study, a scanning electron microscope was used to observe the cellular surface. Ultrasonically induced cell damage increased in the presence of HPD (from 15% to 24%). Compared with ultrasound treatment alone, the fluidity decreased from 5.037 to 3.908, malonaldehyde content and free fatty acid level increased from 0.743 nmol/mL to 0.979 nmol/mL and from 237.180 μmol/L to 730.769 μmol/L, respectively, post ultrasound combined with HPD treatment. Inactivity of adenylate cyclase and guanylate cyclase and significant deformation of the cellular surface were also observed post SDT treatment. Our results suggested that alterations in membrane modality and lipid composition played important roles in SDT-mediated inhibition of tumor growth, even inducing tumor cell death, which might be attributed to a sono-chemical activation mechanism. 相似文献
155.
Qianqian Sun Yuwei Long Hongxi Li Shuang Pan Jidong Yang Shaopu Liu Xiaoli Hu 《Journal of fluorescence》2018,28(2):523-531
Caffeic acid (CA), a familiar color stabilizing reagent, has aroused general concern due to its uncontrolled addition, and thus the detection of CA is increasingly important. In our report, the bright carbon dots (CDs) were prepared via hydrothermal treatment with urea and citric acid act as raw material and their characteristics were discussed through X-ray diffraction (XRD), transmission electron microscopy (TEM) and so on. Impressively, the strong emission of the as-prepared CDs (Quantum Yield: 24.3%) decreased sharply upon a full reaction with the added CA. Hence, we first present an improved strategy for determining CA based upon the quenching of the strong emission of CDs. In this strategy, 0.79–100.0 µmol L??1 caffeic acid could be simply detected, and a detection limit of 0.24 µmol L??1 was allowed. Additionally, CA in red wine samples can be successfully detected by this method and the exploration of the quenching mechanism of the CA-CDs system was done. 相似文献
156.
157.
Based on the principle of acoustic levitation,a single-axis ultrasonic levitation system(SAULS) with convex sides was designed.A normal SAULS only provides a levitation force(LF) against the gravity of the sample.While,such systems also provide an annular clamping force(ACF) surrounding the levitated samples,and improve levitation stability of samples in the standing wave field.Using the finite-difference time-domain method,we investigated the force distributions in different resonance cavities and the factors that influence the magnitude of the levitation force in optimizing the SAULS and the ACF.The theoretical analyses and experimental results indicate that the stability of levitation in this special SAULS is improved with the ACF from its designed convex-side feature.It can be developed into a simple device in levitating and moving samples steadily in related experiments and applications. 相似文献
158.
Nonlinear Dynamics - The self-excitation of spring–mass system subjected to dry friction has been studied for decades because of its interesting and complex nonlinear dynamics behaviors. In... 相似文献
159.
Dr. Yaru Gong Chao Qin Yuteng Zhang Prof. Chunyi Sun Prof. Qinhe Pan Xinlong Wang Zhongmin Su 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(49):22218-22222
Systematic design and self-assembly of metal–organic polyhedra with predictable configurations has been a long-standing challenge in crystal engineering. Herein a concave polyoxovanadate cluster, [V6O6(OCH3)9(SO4)4]5−, which can be generated in situ under specific reaction conditions, is reported. Based on this cluster, a potential trivalent molecular building block, [V6O6(OCH3)9(SO4)(CO2)3]2−, can be obtained by the bridging-ligand-substitution strategy and it possesses appropriate angle information for the design of molecular cubes. Utilizing the face-directed assembly of the trivalent molecular building block and a diverse set of tetratopic carboxylate linkers, a series of metal–organic cubes ( VMOC-1 – VMOC-5 ) with the same topology but different functionalities and dimensions were designed and constructed. An inclusion study using VMOC-3 shows that they are potential molecular receptors for selective capture of size-matching polycyclic aromatic hydrocarbon guest molecules. 相似文献
160.