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21.
Dynamic fragility of bulk metallic glass (BMG) of Zr64Cu16Ni10Al10 alloy is studied by three-point beam bending methods. The fragility parameter mfor Zr64Cu16Ni10Al10 BMG is calculated to be 24.5 at high temperature, which means that the liquid is a "strong" liquid, while to be 13.4 at low temperature which means that the liquid is a "super-strong" liquid. The dynamical behavior of Zr64Cu16Ni10Al10 BMG in the supercooled region undergoes a strong to super-strong transition. To our knowledge, it is the first time that a strong-to-superstrong transition is found in the metallic glass. Using small angle x-ray scattering experiments, we find that this transition is assumed to be related to a phase separation process in supercooled liquid. 相似文献
22.
In this paper, we propose a physical scheme to realize quantum SWAP
gate by using a large-detuned single-mode cavity field and two
identical Rydberg atoms. It is shown that the scheme can also be used
to create multi-atom cluster state. During the interaction between
atom and cavity, the cavity is only virtually excited and thus the
scheme is insensitive to the cavity field states and cavity decay.
With the help of our scheme it is very simple to prepare the $N$-atom
cluster state with perfect fidelity and probability. The practical
feasibility of this method is also discussed. 相似文献
23.
Xiao-Juan Liu An Luo Zhao-Hui Peng Bing-Ju Zhou Ming-Wei Liu Chun-Xia Jia Chun-Lei Jiang 《International Journal of Theoretical Physics》2016,55(11):4740-4750
We investigate quantum echo control and Bell state swapping for two atomic qubits (TAQs) coupling to two-mode vacuum cavity field (TMVCF) environment via two-photon resonance. We discuss the effect of initial entanglement factor ?? and relative coupling strength R=g1/g2 on quantum state fidelity of TAQs, and analyze the relation between three kinds of quantum entanglement(C(ρa),C(ρf),S(ρa)) and quantum state fidelity, then reveal physical essence of quantum echo of TAQs. It is shown that in the identical coupling case R=1, periodic quantum echo of TAQs with π cycle is always produced, and the value of fidelity can be controlled by choosing appropriate ?? and atom-filed interaction time. In the non-identical coupling case R≠1, quantum echoes with periods of π, 2π and 4π can be formed respectively by adjusting R. The characteristics of quantum echo results from the non-Markovianity of TMVCF environment, and then we propose Bell state swapping scheme between TAQs and two-mode cavity field. 相似文献
24.
用TPR并结合XRD、ESR和XPS等测试手段研究了V(Ⅳ,Ⅴ)-ZSM-5、V2O5-/ZSM-5(分别用浸渍法和机械混合法制备)及V2O5样品的还原性能,获得了还原过程中物相及钒离子价态变化的信息,发现分散在分子筛表面上的V(Ⅴ)还原温度比V2O5低,而位于ZSM-5骨架上的V(Ⅴ)却比V2O5更难还原。高于1200K骨架V才开始还原;高于1370K,V-ZSM-5分子筛开始解体并转变成方英石结构,从骨架中析出的V完全还原成低价态。 相似文献
25.
Dong Chen Jing-Dong Chen Hai-Liang Huo Ben-Hai Yu Chun-Lei Wang De-Heng Shi 《Physica B: Condensed Matter》2009,404(21):4162-4167
The equilibrium lattice constants, cell volumes, densities of states and electron density distributions of LaNi4.5Sn0.5 crystal are evaluated by the density functional theory using the plane wave pseudopotential (PW-PP) method. The quasi-harmonic Debye model, using a set of total energy versus cell volume obtained from the PW-PP method, is applied to the study of thermal and vibrational effects. We have analyzed the bulk modulus of LaNi4.5Sn0.5 as a function of temperature up to 1000 K. The thermodynamic properties such as thermal expansion coefficients and heat capacities are also predicted using the quasi-harmonic Debye model. Significant differences in properties are observed at high temperatures and pressures. Moreover, the Debye temperatures are determined from the non-equilibrium Gibbs functions. The calculated results are in excellent agreement with the available experimental data, and compared favorably with other theoretical results. 相似文献
26.
Experiment ^18Ne+^197 Au was performed in Heavy Ion Research Facility Radioactive Ion Beam Line at Lanzhou (RIBLL). The nuclear energy levels of ^18Ne were built by complete kinematical reconstruction of the decay products and diproton decay were observed from ^18Ne excited states. At 6.15 MeV, the experimental relative momentum and angular correlations of the emitted protons are given. The obvious enhancement at |qrol|= 23 MeV/c and θc.m. = 40° shows the experimental criterion of ^2He cluster decay from ^18Ne^q. 相似文献
27.
28.
Liang-Ping Xia Zheng Yang Shao-Yun Yin Wen-Rui Guo Jing-Lei Du Chun-Lei Du 《Frontiers of Physics》2014,9(1):64-68
A fabrication process based on the self-assembling polystyrene spheres is proposed to obtain hole arrayed metal-insulator-metal (HA-MIM) structure for surface enhanced Raman scattering (SERS). The localized field enhancement aroused by the gap resonance in the HA-MIM structure is analyzed by finite-different time domain (FDTD) method. With reference to the theory result, the structure is experimentally fabricated and the Raman scattering spectrum of rhodamine 6G (R6G) is measured by a miniaturized Raman spectrometer. The results shows that the enhancement factor is 3.85 times higher than the control sample with single layered metal hole array. The fabrication process to obtain the HA-MIM SERS substrate is reproducible, fast, large area and low cost. 相似文献
29.
通过声化学法制备了具有生物相容性的磁性蛋白质微胶囊, 利用高强度超声波辐照含有油酸改性磁性的Fe3O4纳米粒子的油相与蛋白质水溶液的两相界面, 只需几分钟即可得到磁性蛋白质微胶囊. 这种制备蛋白质微胶囊的方法快速简便, 高效环保, 可将分散于油相的疏水性药物直接装载, 不破坏药物. 在药物靶向传输等领域具有应用性. 相似文献
30.
The structural and dynamic properties of nanoscale ethanol film on a mica surface are investigated via molecular dynamics simulations.We observe a dense,almost flat ethanol bilayer formed in the vicinity of the mica surface,with the hydrophobic alkyl groups pointing outward from the surface.Remarkably,such ethanol bilayer is laterally well-ordered with patterned adsorption sites.Each ethanol molecule in the first layer donates one hydrogen bond to the surface basal oxygen atoms and accepts one hydrogen bond from that in the second layer.The ethanol molecules within the bilayer exhibit constrained lateral mobility and delayed dynamics as compared with bulk ethanol,whereas those on top of the bilayer have bulk-like characteristics. 相似文献