6,037 research outputs found
Pressure-induced superconductivity in Li-Te electrides
No full textElectrides, which accommodate excess of electrons in lattice interstitials as anions, usually exhibit interesting properties and broad applications. Until now, most electrides, especially at high pressures, show semiconducting/insulating character arising from the strong localization of interstitial and orbital electrons. However, modulating their connectivity could turn them into metals and even superconductors. In this work, with the aid of first-principles particle swarm optimization, we have identified a series of pressure-induced Li-rich electrides in the Li-Te system, in which hollow Lin polyhedra accommodate the excess of electrons. With increasing Li content, these electrides undergo an interesting structural evolution. Meanwhile, the connection type of Lin polyhedra experiences transitions from vertex- or edge sharing, to face sharing, leading to a diverse distribution and connectivity of interstitial electrons. All identified electrides exhibit anionic electrons-dominated metallicity. More interestingly, Li9Te, with the highest content of Li6 octahedra, is superconducting with a critical temperature (Tc) of 10.2 K at 75 GPa, which is much higher than typical electrides (e.g., 12CaO⋅7Al2O3, Ca2N, and Y2C). Its superconductivity mainly originates from the coupling between hybridized electrons (anionic and atomic non-s-state ones) and Te-dominated phonons.The authors acknowledge the funding support from the Natural Science Foundation of China under Grants No.
21873017 and No. 21573037, the Postdoctoral Science Foundation of China under Grant No. 2013M541283, the Natural Science Foundation of Jilin Province (Grant No. 20190201231JC), and the Natural Science Foundation of Hebei Province (Grant No. B2021203030). The work was carried out at National Supercomputer Center in Tianjin, and the calculations were performed on TianHe-1 (A). A.B. acknowledges financial support from the Spanish Ministry of Science and Innovation (Grant No. PID2019-105488GB-I00).Peer reviewe
The political role of the people's liberation army 1949-1973
No full textThis thesis is to study the political role of the People's Liberation Army from the approach of structure and function. The framework of the thesis consists of three major parts, first, the influence of Chinese traditional political culture on, and the formation of, the political role of the PL A; second, the influence of domestic political struggles and external military conflicts on the development of the political role of the PLA; and the third, the analysis of the transition of the PLA's political role from the structure and personnel arrangements of the CCPCC Within the above-mentioned three scopes, this thesis make a thorough discussion on the following: (1) The relationship between the structure of the PRC and the formation of the PLA's political role; (2) How has ideology influenced the army's political role; (3) What is Mao's viewpoint and his influence on the development of the army's political role; (4) What is the link between the army and the party, and how has this developed; (6) What accounts for the expansion of the PLA's political functions; (7) What is the influence of political factional struggles on the PLA's political role; (8) Is it political institution or military institution that controls the recruitment of the military elite; (9) What are the disparities between the military elite in handling international conflicts and what are their political considerations; (10) What is the Party's position in the army; (11) How have the Party’s important meetings and personnel arrangements influenced the rise and fall of the PLA's political role
Fire-retardant-treated low-formaldehyde-emission particleboard made from recycled wood-waste
No full textProperties of low-formaldehyde-emission particleboard made from recycled wood-waste chips sprayed with PMDI/ PF resin
No full textAn Improved Tax Scheme for Selfish Routing
No full textWe study the problem of routing traffic for independent selfish users in a congested network to minimize the total latency. The inefficiency of selfish routing motivates regulating the flow of the system to lower the total latency of the Nash Equilibrium by economic incentives or penalties. When applying tax to the routes, we follow the definition of [Christodoulou et al, Algorithmica, 2014] to define ePoA as the Nash total cost including tax in the taxed network over the optimal cost in the original network. We propose a simple tax scheme consisting of step functions imposed on the links. The tax scheme can be applied to routing games with parallel links, affine cost functions and single-commodity networks to lower the ePoA to at most 4/3 - epsilon, where epsilon only depends on the discrepancy between the links. We show that there exists a tax scheme in the two link case with an ePoA upperbound less than 1.192 which is almost tight. Moreover, we design another tax scheme that lowers ePoA down to 1.281 for routing games with groups of links such that links in the same group are similar to each other and groups are sufficiently different
Supplementary material - Supplemental material for A Pair of Novel Sulfonyl-Containing <i>N</i>-Acetyldopamine Dimeric Enantiomers From <i>Aspongopus chinensis</i>
No full textSupplemental material, Supplementary material, for A Pair of Novel Sulfonyl-Containing N-Acetyldopamine Dimeric Enantiomers From Aspongopus chinensis by Li Liao, Yong-Ming Yan, Te Xu, Hou-Lin Xia and Yong-Xian Cheng in Natural Product Communications</p
Investigation of a scanned cylindrical ultrasound system for breast hyperthermia
No full text[[abstract]]This paper investigates the feasibility of a scanned cylindrical ultrasound system for producing uniform heating from the central to the superficial portions of the breast or localized heating within the breast at a specific location. The proposed system consists of plane ultrasound transducer(s) Mounted on a scanned cylindrical Support. The breast was immersed in water and Surrounded by this system during the treatment. The control parameters considered are the size of the transducer, the ultrasound frequency, the scan angle and the shifting distance between the axes of the breast and the system. Three-dimensional acoustical and thermal models were used to calculate the temperature distribution. Non-perfused phantom experiments were performed to verify the simulation results. Simulation results indicate that high frequency ultrasound Could be used for the Superficial heating, and the scan angle of the transducer could be varied to obtain an appropriate high temperature region to cover the desired treatment region. Low frequency ultrasound Could be used for deep heating and the high temperature region could be moved by shifting the system. In addition, a combination of low and high frequency ultrasound could result in it portion treatment from the central to the superficial breast or an entire breast treatment. Good agreement was obtained between non-perfused experiments and simulation results. The findings of this study can be used to determine the effects of the control parameters of this system, as well as to select the optimal parameters for a specific treatment
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