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Bound 0^(+) Excited States of Three-Body Systems with Short-Range Two-Body Interactions

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Chinese Physics Letters 2013年第5期30卷 37-39页

作者： LIN Qi-hu REN Zhong-Zhou Department of Physics Nanjing UniversityNanjing 210008 Center of Theoretical Nuclear Physics National Laboratory of Heavy-Ion AcceleratorLanzhou 730000

The Faddeev equations are solved to investigate the bound states of three-body systems with short-range two-body interactions. Different bound 0^(+) excited states are obtained depending on the mass ratios of particles, when there is no bound state for two-body sub-systems. On the one hand, a number of bound 0^(+) excited states appear in the system with two heavy particles and a light particle. On the other hand, a weakly bound 0^(+) excited state is obtained in the system with two light particles and a heavy particle, which has not been reported in previous works as far as we know.

关键词： excited states weakly

Consolidation and Compression Property of Nanocrystalline NiAl Synthesized by Mechanical Alloying

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Journal of Materials Science & Technology 1996年第1期12卷 7-10页

作者： Liu, ZG Guo, JT Shi, NL hu, ZQ State Key Lab. for RSA Institute of Metal Research Chinese Academy of Sciences Shenyang 110015 China

The mixture of pure nickel and aluminum powders in the composition of Ni50Al50 was subjected to high energy ball milling. The high energy ball milling to 30 h resulted in the formation of a nanocrystalline NiAl with a grain size of about 10 nm. The as-milled NiAl powder was hot-pressed and the compact with a density of 90% was obtained. It was showed that heating to 900 degrees C and holding for more than 2 h failed to induce the coarsening of the fine nanocrystal in the material, the tendency of grain growth was weak. Compression testing showed that the compression ductility at room temperature reached about 7%. The ductility increased with the experimental temperature while the strength decreased drastically at elevated temperature.

关键词： Nickel alloys

Reconstruction of Emission Coefficients for a Non-axisymmetric Coupling Arc Based on MALDONADO's Method

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Chinese Journal of Mechanical Engineering 2012年第4期25卷 781-785页

作者： XIONG Jun ZHANG Guangjun hu Yutang WU Lin State Key Laboratory of Advanced Welding and Joining Harbin Institute of Technology Harbin 150001 China

The reconstruction of emission coefficient is a key factor for the calculation of temperature ***,most of the researches for determining arc plasmas are based on axisymmetric sources,little has been done to study non-axisymmetric arc *** order to reveal temperatures of a non-axisymmetric coupling arc,the distribution of emission coefficients must be reconstructed in *** this paper,the argon atomic line intensities of the coupling arc are obtained by using the imaging system that involves a high speed camera in conjunction with a neutral and a narrow-band *** converted programme between emission coefficients and emitted intensities is programmed based on MALDONADO＇s method.A displaced Gaussian model is used for evaluating the validity of the converted ***,the emission coefficients of a free burning arc are reconstructed by MALDONADO＇s method and an Abel inversion,respectively,and good agreement is ***,the emission coefficient profiles of the coupling arc are *** results show that the distribution of emission coefficient for the coupling arc is *** emission coefficient profile is similar to an ellipse,and the short axis of the ellipse is in the direction that the two electrodes are arranged *** peak temperature of the coupling arc is in the middle of both *** is a strong interaction between both arcs within the coupling *** proposed research solves difficulties for determining asymmetric arcs and enlarges the application scope of spectroscopic techniques.

关键词： non-axisymmetric coupling arc emission coefficient Twin-electrode TIG spectroscopy image

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原创力:中国影视文化软实力提升的战略起点

艺术百家 2015年第5期31卷 100-105页

作者：胡智锋中国传媒大学科研处

中国影视依托悠久的历史,灿烂的文化,多样的现实,济济的人才等资源优势,创造了载入史册的影视作品,体现出强盛的影视原创力。影视原创力主要就是指影视生产创作领域,影视所拥有的首创性、独特性、突破性和引导性的能力。中国影视原创力... 详细信息

中国影视依托悠久的历史,灿烂的文化,多样的现实,济济的人才等资源优势,创造了载入史册的影视作品,体现出强盛的影视原创力。影视原创力主要就是指影视生产创作领域,影视所拥有的首创性、独特性、突破性和引导性的能力。中国影视原创力在题材、类型、叙事、技艺等方面的历史积淀是深厚而独特的,这是一笔宝贵财富,这方面我们绝不能简单地否定,而应认真地梳理总结。尽管中国影视在历史发展中,显现出相当的"原创力",但也存在着很多困惑和问题。尤其近年来,在世界影视不断变革、创新的冲击下,中国影视原创力显得相对疲软、薄弱和乏力,题材、类型、叙事、技艺等的首创、独创、突破与引导都相当不足,甚至陷于"原创力焦虑症"。文章认为,提升中国影视原创力的理念与对策至少有以下三点:一是树立文化自信理念,营造健康良性的环境氛围;二是树立制度自信理念,建立中国特色的制度体系;三是树立专业自信,夯实影视发展的深厚基础。

关键词：当代中国文化建设原创力中国影视文化软实力创新引导自信

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与学习记忆相关的睡眠新功能——突触稳态

生物化学与生物物理进展 2009年第3期36卷 269-273页

作者：李洋陈芳胡志安第三军医大学生理教研室重庆400038

近年来的许多研究证实睡眠有利于学习和记忆.不但学习后的睡眠具有记忆巩固功能,而且学习前的睡眠对于随后的学习也是必需的.长时间觉醒学习后脑内突触连接增多、增强,导致突触空间饱和,阻碍随后继续学习.睡眠的作用是减弱突触连接到基... 详细信息

近年来的许多研究证实睡眠有利于学习和记忆.不但学习后的睡眠具有记忆巩固功能,而且学习前的睡眠对于随后的学习也是必需的.长时间觉醒学习后脑内突触连接增多、增强,导致突触空间饱和,阻碍随后继续学习.睡眠的作用是减弱突触连接到基础水平,为随后的学习记忆提供充足的空间和能量.

关键词：睡眠慢波活动突触稳态突触权重可塑性学习记忆

Urban construction land demand prediction and spatial pattern simulation under carbon peak and neutrality goals:A case study of Guangzhou,China

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Journal of Geographical Sciences 2022年第11期32卷 2251-2270页

作者： hu Xintao LI zhihui CAI Yumei WU Feng Key Laboratory of Land Surface Pattern and Simulation Institute of Geographic Sciences and Natural Resources ResearchCASBeijing 100101China College of Land Science and Technology China Agricultural UniversityBeijing 100193China University of Chinese Academy of Sciences Beijing 100049China Research Centre for Territorial Spatial Planning Ministry of Natural Resources of the People’s Republic of ChinaBeijing 100812China

Urban construction land has relatively high human activity and high carbon *** on urban construction land prediction under carbon peak and neutrality goals(hereafter“dual carbon”goals)is important for territorial spatial *** study analyzed quantitative relationships between carbon emissions and urban construction land,and then modified the construction land demand prediction ***,an integrated model for urban construction land demand prediction and spatial pattern simulation under“dual carbon”goals was developed,where urban construction land suitability was modified based on carbon source and sink capacity of different land-use *** Guangzhou as a case study,the integrated model was validated and applied to simulate the spatiotemporal dynamics of its urban construction land during 2030–2060 under baseline development and“dual carbon”goals *** simulation results showed that Guangzhou’s urban construction land expanded rapidly until 2030,with the spatial pattern not showing an intensive development ***’s urban construction land expansion slowed during 2030–2060,with an average annual growth rate of 0.2%,and a centralized spatial pattern *** the“dual carbon”goal scenario,Guangzhou’s urban construction land evolved into a polycentric development pattern in *** with the baseline development scenario,urban construction land expansion in Guangzhou during 2030–2060 is slower,with an average annual growth rate of only 0.1%,and the polycentric development pattern of urban construction land was more ***,land maintenance and growth,that is,a carbon sink,is more obvious under the“dual carbon”goals scenario,with the forest land area nearly 10.6%higher than that under the baseline development *** study of urban construction land demand prediction and spatial pattern simulation under“dual carbon”goals provides a scientific decision-making support tool for territorial spati

关键词： carbon peak and neutrality goals urban construction land demand prediction spatial pattern simulation Guangzhou

我国城镇居民收入基尼系数的估计及其群体阶层效应——基于省级收入分组数据的研究

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当代财经 2016年第10期 15-24页

作者：胡志军江西财经大学金融学院江西南昌330013

基于各省城镇居民收入分组数据,通过拟合收入分布方法估计了2008-2012年间各省城镇基尼系数及总体城镇基尼系数。结果发现,城镇总体基尼系数呈现下降趋势,由2008年的0.3415下降到2012年的0.3154;其中,青海和重庆分别是5年间城镇基尼系... 详细信息

基于各省城镇居民收入分组数据,通过拟合收入分布方法估计了2008-2012年间各省城镇基尼系数及总体城镇基尼系数。结果发现,城镇总体基尼系数呈现下降趋势,由2008年的0.3415下降到2012年的0.3154;其中,青海和重庆分别是5年间城镇基尼系数最大和最小的地区。按照基尼系数的完全分解框架,对城镇收入差距进行了按东、中、西地区分组的群体分解,结果表明,城镇收入差距绝大部分来自组内差距;东部地区的阶层效应最为明显,即与中、西部地区相比,东部地区更加趋向于形成一个阶层;进一步按收入分组的群体分解结果也同样表明,城镇收入差距绝大部分来自组内差距,高收入组群体更加趋向于形成一个阶层。而且,我国城镇居民收入分布的群体阶层效应越来越明显。

关键词：收入分组数据基尼系数交叉效应阶层效应

Joint Pilot Design and Beamforming Optimization in Massive MIMO Surveillance Systems

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China Communications 2022年第4期19卷 83-97页

作者： Caihong Kai Xiangru Zhang Xinyue hu Wei huang School of Computer Science and Information Engineering Hefei University of TechnologyHefei 230601China Intelligent Interconnected Systems Laboratory of Anhui Province Hefei University of TechnologyHefei 230601China School of Electronics and Information Engineering Anhui UniversityHefei 230601China

This paper proposes a novel joint channel estimation and beamforming scheme for the massive multiple-input-multiple-output(MIMO)frequency-division duplexing(FDD) wireless legitimate surveillance system. With the proposed scheme,the monitor with the full duplex capability realizes the proactive eavesdropping of the suspicious link by leveraging the pilot attack approach. Specifically, exploiting the effective eavesdropping rate and the mean square error as performance metrics and setting a total power budget at the training and transmission phases,while guaranteeing the information from suspicious source can be successfully decode, joint pilot design,power allocation and beamforming strategy are formulated as optimization problems for the two objective functions: MSE and effective eavesdropping rate. A closed-form expression of the optimal pilot with the limited length can be obtained via the channel correlation. The optimal power problem at the training phase can be solved by a simple bisection method. Then,based on the obtained imperfect estimated channel,the jamming beamforming at monitor optimization algorithm is proposed by utilizing the convex Semidefinite Programming approach to maximize the effective eavesdropping rate. Numerical results show that the proposed joint pilot design, power allocation and beamforming optimization scheme can improve the surveillance performance of the legitimate monitor as compared to the existing passive eavesdropping and jamming-assisted eavesdropping.

关键词： proactive eavesdropping massive MIMO channel estimation pilot contamination beamforming

Direct conversion of furfural to levulinic acid/ester in dimethoxymethane:Understanding the mechanism for polymerization

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Green Energy & Environment 2019年第4期4卷 400-413页

作者： Yuewen Shao Xun hu Zhanming Zhang Kai Sun Guanggang Gao Tao Wei Shu Zhang Song hu Jun Xiang Yi Wang School of Material Science and Engineering University of JinanJinan250022China College of Materials Science and Engineering Nanjing Forestry UniversityNanjing210037JiangsuChina School of Energy and Power Engineering Huazhong University of Science and TechnologyWuhan430074China

This study investigated the conversion of furfural to 5-hydroxymethylfurfural(HMF)and further to levulinic acid/ester in dimethoxymethane under acidic conditions,with the particular focus on understanding the mechanism for polymer *** results showed that furfural could react with dimethoxymethane via electrophilic substitution reaction to form HMF or the ether/acetal of HMF,which were further converted to levulinic acid and methyl *** polymerization of furfural and the cross-polymerization between dimethoxymethane and the levulinic acid/ester produced were the main side reactions leading to the decreased yields of levulinic acid/*** to the other solvent,methanol as the co-solvent helped to alleviate but not totally inhibited the occurrences of the polymerization,as the polymerization reactions via aldol condensation did not eliminate the C=O *** a consequence,the polymerization reactions continued to *** co-solvent used such as guaiacol,dimethyl sulfoxide and acetone interfered with the transformation of furfural to HMF or aided the polymerization *** polymer produced from the reactions between furfural and DMM was different from that produced from levulinic acid/*** former had a higher crystallinity,while the latter was more *** DRIFTS and TG-MS studies showed that the polymer had the carboxylic group,methyl group and the aliphatic structure in the *** removal of these functionalities was accompanied by the aromatization of the *** condensation of DMM with levulinic acid/ester was the key reason for the diminished production of levulinic acid/ester.

关键词： polymerization methane dimethoxy