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81.
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. 相似文献
82.
83.
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. 相似文献
84.
Atomic force microscopy investigation of growth process of organic TCNQ aggregates on SiO2 and mica substrates 下载免费PDF全文
<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. 相似文献
85.
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. 相似文献
86.
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.
相似文献
87.
The generation of Entangled Qudits and their Application in Probabilistic Superdense Coding 下载免费PDF全文
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. 相似文献
88.
Ying Ding Qing Yan Jing-Wen Ruan Yan-Qing Zhang Wen-Jie Li Yu-Jiao Zhang Yan Li Hongxin Dong Yuan-Shan Zeng 《BMC neuroscience》2009,10(1):35
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. 相似文献89.
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
gs gp /\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. 相似文献
90.
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. 相似文献