Boson peak in Sm-Al-Co ternary metallic glasses and its possible structural origin

The low temperature specific heat of Sm-Al-Co ternary metallic glasses is investigated and a clear anomaly associated with the Boson peak is identified. While this anomaly depends slightly on the chemical composition, it has no dependence on external magnetic field. To figure out the mechanism of the Boson peak, we interpret the data within various model frameworks. Unlike earlier work, our study shows that this Boson peak is mainly ascribed to an additional T² term of the specific heat, which may originate from the quasi-two-dimensional and short-range ordered structure units possibly existing in the metallic glasses.     

双势阱中冷原子的关联隧穿

研究了在不同的相互作用和隧穿耦合强度比值情况下双势阱中冷原子的隧穿现象.两格点Bose-Hubbard模型不能完全解释实验.为此,对此模型做了高阶修正.取双势阱的基态和第一激发态作基矢,写出哈密顿量的表示,解释了用两格点Bose-Hubbard模型分析实验时参数不能定量符合的原因.另外,通过计算两阱中原子纠缠度的变化,结合三态上原子布居数分布,直观描述了整个隧穿过程.     

First experimental research of the bunch compressor at CAEP

Magnetic bunch compressor is one of the key technologies on the path to next generation accelerator driven facilities. In this paper we report the design principles and the first experimental research of the bunch compressor developed at Chinese Academy of Engineering Physics （CAEP）. The length of the bunch after compressor is found to be about 0.7 ps （rms） and the peak current exceeds 500 A when operated in the optimized condition. The sensitivity of the bunch length on the phase of the acceleration field and magnetic field of the bunch compressor was also measured and analyzed.     

Atomic force microscopy investigation of growth process of organic TCNQ aggregates on SiO2 and mica substrates

<正>Deposition patterns of tetracyanoquinodimethane(TCNQ) molecules on different surfaces are investigated by atomic force microscopy.A homemade physical vapour deposition system allows the better control of molecule deposition. Taking advantage of this system,we investigate TCNQ thin film growth on both SiO_2 and mica surfaces.It is found that dense island patterns form at a high deposition rate,and a unique seahorse-like pattern forms at a low deposition rate.Growth patterns on different substrates suggest that the fractal pattern formation is dominated by molecule-molecule interaction.Finally,a phenomenal "two-branch" model is proposed to simulate the growth process of the seahorse pattern.     

Study of lower emittance dedicated synchrotron radiation mode for the BEPCⅡ

In this paper,a dedicated synchrotron radiation （SR） mode for the BEPCⅡ with an emittance of 85 nm has been designed,including the linear lattice,chromaticity correction and dynamic aperture optimization.The emittance of the new mode is about 60% of the previous mode used for routine operation of the BEPCⅡ .The effect of wigglers on the linear lattice was compensated and the total dynamic aperture including the wigglers’ nonlinear effect was estimated.The preliminary commissioning at the end of 2008 and the formal operation with the new mode confirmed its merits.     

Density functional theory study of surface catalysis and adsorption on several elements in Group I-B and VIII

This review deals with the high-throughput field in surface catalysis and adsorption. Special focus is placed on advanced methods for knowledge discovery such as density functional theory (DFT) simulations. An inventory of successful cases on several elements in Group I-B and VIII is reported, including the relevant data and knowledge management, which are very important in chemical industry, fuel cell, and environment protection, for both scientific and economical reasons.      

The generation of Entangled Qudits and their Application in Probabilistic Superdense Coding

A scheme of the generation of entangled qutrits is presented, and then is generalized to entangled ququads and entangled qudits. With the entangled qutrits, an experimental scheme of probability superdense coding with only linear optical elements is proposed. It is shown that this scheme will be suitable for the entangled ququads, even for the entangled qudits if some nonlinearity is used. This scheme is feasible in the laboratory with the current experimental technology.     

Electro-acupuncture promotes survival, differentiation of the bone marrow mesenchymal stem cells as well as functional recovery in the spinal cord-transected rats

Background  

Bone marrow mesenchymal stem cells (MSCs) are one of the potential tools for treatment of the spinal cord injury; however, the survival and differentiation of MSCs in an injured spinal cord still need to be improved. In the present study, we investigated whether Governor Vessel electro-acupuncture (EA) could efficiently promote bone marrow mesenchymal stem cells (MSCs) survival and differentiation, axonal regeneration and finally, functional recovery in the transected spinal cord.     

Chirality-asymmetry force between ɑ-quartz and copper block

The chirality-asymmetry macroscopic force mediated by light pseudoscalar particles between α -quartz and some achiral matter is studied. If this force between achiral source mass and α -quartz with some chirality is attractive, it will become repulsive when the chirality of the α -quartz crystal is changed. According to the tested limits of the coupling constant g_s g_p /\hbar c< 1.5× 10^-24 at the Compton wavelength λ = 10^-3 m, the force (F) between a 0.08× 0.08× 0.002 m³ block of α -quartz and a 0.08× 0.08× 0.01 m³ copper block with a separation being 0.5× 10^-3 \mbox{m} in between, is estimated from the published data at less than 4.64× 10^-24 N, i.e. F < 4.64× 10^-24 N.     

Linear optical realization of unambiguous quantum state comparison

In this paper, we propose an experimental scheme for unambiguous quantum state comparison assisted by linear optical manipulations, twin-photons produced from parametric down-conversion, and postselection from the coincidence measurement. In this scheme the preparation of the general two mixed qubit states with arbitrary prior probabilities and the realization of the optimal POVMs for unambiguous quantum state comparison are presented. This proposal is feasible by current experimental technology, and may be used in single-qubit quantum fingerprinting.