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Continuous-Time Independent Edge-Markovian Random Graph Process

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Chinese Annals of Mathematics,Series B 2016年第1期37卷 73-82页

作者： Ruijie DU hanxing WANG Yunbin FU Department of Mathematics Shanghai University School of Mathematics and Information Shanghai Lixin University of Commerce

In this paper, the continuous-time independent edge-Markovian random graph process model is constructed. The authors also define the interval isolated nodes of the random graph process, study the distribution sequence of the number of isolated nodes and the probability of having no isolated nodes when the initial distribution of the random graph process is stationary distribution, derive the lower limit of the probability in which two arbitrary nodes are connected and the random graph is also connected, and prove that the random graph is almost everywhere connected when the number of nodes is sufficiently large.

关键词： Complex networks Random graph Random graph process Stationary distribution Independent edge-Markovian random graph process

The early signal substances induced by heat stress in brains of mice

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Frontiers of Medicine 2008年第4期2卷 391-395页

作者： Chunxu WANG hanxing WANG Department of Anatomy Tongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430030China The Affiliated Hospital of Hanfeng Plant Handan 056200China

To study the effects of early signal substances induced by heat stress in brains of Kunming mice,six-month-old mice(n 572)were pretreated with heat stress and subsequent ischemia/reperfusion by clipping of their bilateral cervical common arteries for 7 *** to different treatments,animals were randomly divided into four groups:(1)normal control group;(2)heat stress pre-treatment followed by ischemia and reperfusion group(HS/IR);(3)ischemia and reperfusion group(IR);(4)heat stress group(HS).Animals in the later three groups were subdivided into 3 subgroups(1 day,4 days,14 days),*** changes in the expression of cAMP res-ponse element binding protein(CREB)and calcitonin gene-related peptide(CGRP)were detected by immuno-histochemistry and computer image analysis *** results showed that compared with the normal group,the expressions of CREB in the hippocampal CA1 region increased significantly in the HS,HS/IR and IR groups(P,0.05).Compared to the normal group,heat stress could result in CGRP excretion and redistribution in the cerebrum,with the highest level in the 4 d HS/IR *** heat stress,CGRP immunoreactivity was observed in varicose fibers and neuronal perikarya within the CA1 *** results indicate that heat stress can induce CREB expression,which in turn stimulates CGRP secretion.

关键词： heat stress pretreatment brain early signal substance reperfusion injury

基于注入锁定技术的单频连续高功率1342 nm Nd:YVO_(4)激光器

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红外与激光工程 2024年第1期53卷 114-120页

作者：周子涵王志敏薄勇张丰丰赵文成付莉何汉星崔大复彭钦军中国科学院理化技术研究所固体激光重点实验室北京100190 中国科学院理化技术研究所功能晶体和激光技术重点实验室北京100190 中国科学院大学北京100049

研究了一种基于注入锁定技术的888 nm半导体激光器(LD)泵浦的高功率单频可调谐1 342 nm Nd:YVO_(4)激光器。采用最大输出功率20 mW分布式反馈单频半导体1 342 nm激光器作为注入种子,利用lock-in (LI)技术,对LD端泵的Nd:YVO_(4)环形腔激... 详细信息

研究了一种基于注入锁定技术的888 nm半导体激光器(LD)泵浦的高功率单频可调谐1 342 nm Nd:YVO_(4)激光器。采用最大输出功率20 mW分布式反馈单频半导体1 342 nm激光器作为注入种子,利用lock-in (LI)技术,对LD端泵的Nd:YVO_(4)环形腔激光器进行种子注入,实现了单频可调谐激光输出。激光器最大平均输出功率为13.9 W,测量的线宽为41 MHz,调谐范围为1 341.677 4~1 341.802 5 nm。x轴和y轴的光束质量M2因子分别为M_(x)^(2)=1.30和M_(y)^(2)=1.23。实验结果表明:与先前文献报道的注入锁定1 342 nm可调谐激光的结果相比,所需种子功率大幅减小,输出功率也有所提升。

关键词： Nd:YVO_(4)激光器连续波单频可调谐注入锁定

高校大学生PDP标量体系研究——英国经验的启示

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高教学刊 2024年第12期10卷 25-28页

作者：王东红付汉星湖北经济学院统计与数学学院武汉430205 中南财经政法大学公共管理学院武汉430073 湖北数据与分析中心武汉430205

随着高等教育的演变由精英化到大众化再到普及化,社会对高等教育的质量和责任提出更高的要求。高等院校如何对接社会需求,教育与教学过程学生能力的开发和培养问题值得关注。英国教育学者最先关注大学生能力开发,并探索开启学生主动学... 详细信息

随着高等教育的演变由精英化到大众化再到普及化,社会对高等教育的质量和责任提出更高的要求。高等院校如何对接社会需求,教育与教学过程学生能力的开发和培养问题值得关注。英国教育学者最先关注大学生能力开发,并探索开启学生主动学习与思索意识,挖掘成长的潜能,开发适应社会工作能力的教育开发模式,形成较有影响的教育理论探索与教育实践融合的就业能力模式。该研究对检索的2005—2023年134篇相关文献以及英国高等教育机构的实施方案进行分析,对大学生个人发展规划的概念、理论基础和具体实施案例进行梳理,进而在借鉴英国经验的基础上提供改进我国高等教育的启示。

关键词：个人发展规划实施方案英国启示大学生

Enhanced Electrochemical Performances of Ni Doped Cr_(8)O_(21)Cathode Materials for Lithium-ion Batteries

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Journal of Wuhan University of Technology(Materials Science) 2023年第6期38卷 1242-1247页

作者： TANG Guoli LIU hanxing YU Zhiyong YANG Bo KONG Linghua School of Materials Science and Engineering Wuhan University of TechnologyWuhan 430070China International School of Materials Science and Engineering Wuhan University of TechnologyWuhan 430070China State Key Laboratory of Advanced Technology for Materials Synthesis and Processing Wuhan 430070China

Cathode materials,nickel doped Cr_(8)O_(21),were synthesized by a solid-state *** effects of Ni doping on the electrochemical performances of Cr_(8)O_(21) were *** experimental results show that the discharge capacities of the samples depend on the nickel contents,which increases firstly and then decreases with increasing Ni *** Ni_(0.5)Cr_(7.5)O_(21)delivers a first capacity up to 392.6 m Ah·g^(-1)at *** addition,Ni doped sample also demonstrates enhanced cycling stability and rate capability compared with that of the bare Cr_(8)O_(21).At 1 C,an initial discharge capacity of 348.7 m Ah·g^(-1)was achieved for Ni_(0.5)Cr_(7.5)O_(21),much higher than 271.4 m Ah·g^(-1)of the un-doped sample,with an increase of more than 28%.Electrochemical impedance spectroscopy results confirm that Ni doping reduces the growth of interface resistance and charge transfer resistance,which is conducive to the electrochemical kinetic behaviors during charge-discharge.

关键词： Cr_(8)O_(21) cathode material doping electrochemical performances lithium-ion batteries

Protective roles of heat stress on the neurons in hippocampal CA1 region of mice

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Frontiers of Medicine 2007年第4期1卷 418-422页

作者： WANG Chunxu WANG hanxing Department of Anatomy Tongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430030China The Stuff Hospital of Hanfeng Plant Handan 056200China

The effects of heat stress on the neurons in hippocampal CA1 region of brain ischemia/reperfusion were *** mice were pretreated with heat stress fol-lowed by ischemia/reperfusion by clipping bilateral cervical common arteries for 7 *** were divided randomly into four groups as follows:(1)normal control group;(2)heat stress pretreated subsequent to ischemia/reperfusion group(HS/IR);(3)ischemia/reperfusion group(IR);and(4)heat stress group(HS).Animals in the last three groups were subdivided into three subgroups:1 d,4 d,14 d *** Morris water maze was used to test the ability of learning and memorizing,Nissl staining was used to count the average number of survived neurons in hippocampal CA1 region,and immunohistochemistry combined with image analysis system to detect the changes of Microtubule associated protein 2(MAP-2)*** results showed that mice in IR group exhibited increased escape latency when compared with that of normal,HS and HS/IR groups(P<0.01),and the mice in IR group adopted an inefficient search strategy,major in circling and restricted searching *** staining results showed a significant reduction in the number of pyra-midal neurons in hippocampal CA1 regions in HS/IR and IR groups,with a decrease in IR group(P<0.01).Compared with normal group,the expression of MAP-2 in hippocampal CA1 region obviously decreased in IR group(P<0.05).The present results indicate that heat stress pretreatment can improve the spatial learning and memorizing function through protection to hippocampal neurons.

关键词： heat stress disorders hippocampus microtubule-associated proteins reperfusion injury

Long-term impacts of land-use change on dynamics of tropical soil carbon and nitrogen pools

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Journal of Environmental Sciences 2004年第2期16卷 256-261页

作者： YANGJing-cheng HUANGJian-hui PANQing-min TANGJian-wei hanxing-guo LaboratoryofQuantitativeVegetationEcology InstituteofBotanyChineseAcademyofSciencesBeijing100093China. XishuangbannaTropicalBotanicalGarden ChineseAcademyofSciencesMengla666303China

Land-use changes, especially the conversion of native forest vegetation to cropland and plantations in tropical region, can alter soil C and N pools and N availability for plant uptake. Deforestation, followed by shifting cultivation and establishment of rubber tree plantation, is a common land-use change in Xishuangbanna, southwest China. However the influence of this kind of land-use change on soil C and N dynamics in this region remains poorly understood. This study was conducted to assess the effects of land-use change on soil C and N pools. Soil samples were collected on five adjacent plots, which belong to three land-use types including secondary forest-an acuminate banana(Musa itinerans) secondary forest and a male bamboo(Dendrocalamus membranaceae) secondary forest, shifting cultivation, and rubber tree (Hevea brasiliensis (H.B.K.) Muell. Arg.) plantation(one plot is 3-year-old, and another is 7-year-old). We measured soil bulk density (BD), pH value, moisture content and concentrations of soil organic carbon(SOC), total soil nitrogen(TSN), and inorganic N(NO - 3-N and NH + 4-N ) at 0—3, 3—20, 20—40 and 40—60 cm depths, and calculated C and N pools in 0—20, 20—40, 40—60, and 0—60 cm soil layers. Compared with the adjacent secondary forests, shifting cultivation and establishment of rubber tree plantations resulted in significant decline in concentrations and stocks of SOC and TSN in 0—20 and 0—60 cm soil layers, and increase in pH and bulk density at 0—3, 3—20, and 20—40 cm depths. Soil moisture content decreased only in 0—20 cm surface soils in shifting cultivation and plantations. The dynamics of mineral N was much more complex, which had different trends among depths and ecosystems. Compared with the secondary forests, SOC stocks in 0—20 cm surface soils in shifting cultivation and rubber tree plantations(3-year-old plantation and 7-year-old plantation) decreased by 34.0%, 33%, and 23%; and TSN stocks decreased by 32 2%, 20.4%, and 20.4%, respect

关键词： soil organic carbon(SOC) total soil nitrogen(TSN) inorganic nitrogen land-use change tropical soil Xishuangbana

Preparation of layered oxide Li(Co_(1/3)Ni_(1/3)Mn_(1/3))O_2 via the sol-gel process

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Rare Metals 2008年第2期27卷 158-164页

作者： ZHANG Wen LIU hanxing HU Chen ZHU Xianjun LI Yanxi State Key Laboratory of Advanced Technology for Material Synthesis and Processing Wuhan University of Technology Wuhan 430070 China

To obtain homogenous layered oxide Li（Co1/3Ni1/3Mn1/3）O2 as a lithium insertion positive electrode material, the sol-gel process using citric acid as a chelating agent was applied. The material Li（Co1/3Ni1/3Mn1/3）O2 was synthesized at different calcination temperatures. XRD experiment indicated that the layered Li（Co1/3Ni1/3Mn1/3）O2 material could be synthesized at a lower temperature of 800℃, and the oxidation state of Co, Ni, and Mn in the cathode confirmed by XPS were ＋3, ＋2, and ＋4, respectively. SEM observations showed that the synthesized material could form homogenous particle morphology with the particle size of about 200 nm. In spite of different calcination temperatures, the charge-discharge curves of all the samples for the initial cycle were similar, and the cathode synthesized at 900℃ showed a small irreversible capacity loss of 11.24% and a high discharge capacity of 212.2 mAh·g^-1 in the voltage range of 2.9-4.6 V.

关键词： lithium-ion battery layered transition metal oxide sol-gel process high capacity

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居民消费结构转型升级的碳减排效应研究

商业经济研究 2024年第2期 46-50页

作者：王东红任金垚潘曼刘赋仪付汉星中南财经政法大学公共管理学院湖北武汉430073 湖北经济学院统计与数学学院湖北数据与分析中心湖北经济学院金融学院湖北武汉430205

降低各地区的碳排放强度对于“双碳”目标的实现具有重要意义。近年来,我国居民消费结构发生了重大变化,居民消费结构转型升级对碳排放强度有显著影响。本文采用2000-2020年我国30个省级地区的空间面板样本数据,利用动态面板模型研究了... 详细信息

降低各地区的碳排放强度对于“双碳”目标的实现具有重要意义。近年来,我国居民消费结构发生了重大变化,居民消费结构转型升级对碳排放强度有显著影响。本文采用2000-2020年我国30个省级地区的空间面板样本数据,利用动态面板模型研究了居民消费结构转型对碳排放强度是否存在非线性影响机制;对产业结构能否充当中介变量进行分析,对东中西部地区的异质性进行了研究;研究表明居民消费结构对碳排放强度能够产生明显的抑制效果,东部地区的影响更为显著,并且产业结构能够作为中介效应影响碳排放强度。本研究结论与政策启示对于居民消费结构转型升级实现“双碳”目标具有一定的现实意义。

关键词：碳减排居民消费结构产业结构动态面板模型(Two-step SYS-GMM)