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Analysis of the abnormal resistance in AlGaN/GaN heterostructure's ohmic contact tests

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Rare Metals 2007年第5期26卷 463-469页

作者： xu Chuan WANG jinyan JIN Haiyan ZHOU Jin WEN Cheng P Institute of Microelectronics Peking University Beijing 100871 China

Ti/Al/Ti/Au and Ti/Al/Ni/Au ohmic contacts were fabricated on AlGaN/GaN heterostructure under different temperatures of rapid thermal processing （RTP）. Since abnormal resistance values were observed during the contact resistance testing,the surface morphology and contact borders of the samples were analyzed to determine the physical mechanism. Such abnormal phenomenon is found to originate from cracking of the AlGaN layer during RTP,flowing of Ti/Al metallic liquid along the crevices,and continuous reaction of the metallic liquid with AlGaN/GaN. Such processes result in abnormal conduction channels. The possible mechanism of the crevice formation was discussed,and the possible solutions to avoid the crevices were proposed.

关键词： semiconductor technology abnormal resistance EDX AlGaN/GaN ohmic contact crevices

Three types of maximally entangled states for a two-particle system

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Science China(Physics,Mechanics & Astronomy) 2004年第1期47卷 36-41页

作者： RUAN Manqi, xu Gang & ZENG jinyan Department of Physics, Tsinghua University, Beijing 100084, China Department of Physics, Peking University, Beijing 100871, China Correspondence should be addressed to Zeng jinyan (email: jyzeng@***) Received June 16, 2003 1. Department of Physics Tsinghua University 100084 Beijing China 2. Department of Physics Peking University 100871 Beijing China

For a two-particle (spin 1/2) system, three fundamental forms of complete sets of commuting observables (CSCO) composed of two-body operatorsσ 1α σ 2α are given. The corresponding simultaneous eigenstates constitute three types of maximally entangled states, one of which is the well known Bell basis. This paper discusses the possible pairs of spin observables whose simultaneous measurement outcomes are definitely correlated in probabilistic fashion.

关键词： spin entangled state, complete set of commuting observables, two-body operator.

Sand barrier morphological evolution based on time series remote sensing images:a case study of Anhaiao,Pingtan

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Acta Oceanologica Sinica 2020年第12期39卷 121-134页

作者： Heshan Lin Xingguang Yu Zhigang Yu Yikang Gao jinyan xu Aiping Feng Zhijun Liu Degang Jiang Fan Yu College of Environmental Science and Engineering Ocean University of ChinaQingdao 266100China Island Research Center Ministry of Natural ResourcesPingtan 350400China Third Institute of Oceanography Ministry of Natural ResourcesXiamen 361005China Ministry of Natural Resources Beijing 100812China

The morphological evolution of the sand barrier in the Anhaiao coastal zone of Pingtan from 1996 to 2018 was *** correction was used to refine the location of the coastline.A standard deviation ellipse method was applied to further analyze the movement of the barrier head with the axis and rotation angle.A natural neighbor interpolation(NNI)method was carried out to calculate the terrain of the intertidal area,and the erosion and deposition characteristics were illustrated based on the *** results showed that the northern part of the sand barrier facing the lagoon area was deposited over the whole studied period,while erosion has always occurred in the southern part of the sand barrier facing the open *** erosion and deposition were slightly different on both sides of the barrier head due to hydrodynamic *** middle sand barrier moved 102.60 m away from its original location in 1996,and the end of the barrier moved 65.45 *** head of the sand barrier continued moving 379 m to the ***,the preliminary morphological evolution of the sand barrier corresponding to the distance and direction of movement was detected.

关键词： sand barrier dynamic evolution movement reclamation

Scalp acupuncture Yikang therapy on Baihui(GV20),Sishencong(EX-HN1),Zhisanzhen,Niesanzhen improves neurobehavior in young rats with cerebral palsy through Notch signaling pathway

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Journal of Traditional Chinese Medicine 2023年第2期43卷 337-342页

作者： xuE Jianyi xu jinyan HUANG Mao YU Wentao YAN Yihui YAN Yuanjie YIN Zhenjin LU Qian PENG Wanying YAN Siyang Department of Acupuncture and Message Hebei University of Chinese MedicineShijiazhuang 050091China Department of Child Rehabilitation the First Affiliated Hospital of Hebei University of Chinese MedicineShijiazhuang 050013China the second Outpatient Department Hebei University of Chinese MedicineShijiazhuang 050090China School of Basic Medicine Hebei University of Chinese MedicineShijiazhuang 050200China

OBJECTIVE:To investigate the efficacy of scalp acupuncture Yikang therapy on Baihui(GV20),Sishencong(EX-HN1),Zhisanzhen,Niesanzhen,on neurobehavior in young rats with cerebral palsy based on Notch signaling ***:Thirty 7-day-old rats were randomly divided into sham,model and acupuncture,10 rats in each *** cerebral palsy model was established by the accepted modeling method,the acupuncture group selected"Baihui(GV20)","Sishencong(EX-HN1)","Zhisanzhen"and"Niesanzhen"for intervention 24 h after the model was *** body masses were recorded before and after the treatment,*** the intervention,the rats were subjected to suspension experiment,slope experiment,tactile stimulation experiment and Morris water maze *** the end of the experiment,the morphological changes of hippocampal histology were observed by hematoxylineosin(HE)staining under light microscope,and the expression of Notch1,Notch3 and Hes5 were detected by Western blot and quantitative real-time polymerase chain reaction(PCR).RESULTS:The changes in body mass of the rats in each group were different;in behavioral experiments,compared with the sham,the suspension time of the model was shortened,the slope experiment,tactile stimulation experiment,and escape latency time were prolonged,and the number of platform crossing was reduced in the model,compared with the model,the suspension time of the acupuncture was prolonged,the slope experiment,tactile stimulation experiment,and escape latency time were shortened,and the number of platform crossing times was increased;HE staining showed severe hippocampal damage in the model and reduced hippocampal damage in the *** Blot and real-time fluorescence quantitative PCR showed that the expression of Notch1,Notch3 and Hes5 were increased in the model and the expression of Notch1,Notch3,Hes5 in acupuncture were ***:Scalp acupuncture Yikang therapy may improve neurobehavior and reduce brain inj

关键词： cerebral palsy scalp acupuncture Yikang therapy hippocampal tissue Notch signaling pathway

Some Domestic Strontium Carbonate Producers Will Be Beaten out

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China Chemical Reporter 2008年第10期19卷 16-16页

作者： Wu Weidong xu Qing Nanjing jinyan Strontium Industry Co.,Ltd.

1 Surplus capacity and decreasing profit in 2007 With negative impacts from the recession of the color TV picture tube production and the elimination of the export rebate,China’s strontium carbonate manufacturing sector suffered from oversupply in *** domestic producers cut their operation rates or shifted to producing other chemicals in order to deal with the slack demand,but the price of strontium carbonate still dropped from around RMB4 200 per ton at the be-ginning of 2007 to around RMB3 200 per ton at the end of the *** the require-ments for saving energy and reducing pol-lutants get higher and higher,producers

关键词： sector chemicals producing profit carbonate suffer

Cu_(2)O骸晶的制备及其光催化性能探讨

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功能材料 2021年第7期52卷 7143-7148,7157页

作者：徐鑫邱志惠张琦徐金燕桂林理工大学地球科学学院广西桂林541006 广西师范大学化学与药学学院广西桂林541004

以醋酸铜为原料,NaOH为添加剂,谷氨酸与山梨醇1∶1混合作为还原剂,在水热条件下获得了八面体晶面空洞的Cu_(2)O晶体。采用XRD,SEM以及紫外-可见漫反射光谱仪(UV-Vis)进行表征,探讨了Cu_(2)O骸晶的形成条件及对光催化的影响。分析认为,... 详细信息

以醋酸铜为原料,NaOH为添加剂,谷氨酸与山梨醇1∶1混合作为还原剂,在水热条件下获得了八面体晶面空洞的Cu_(2)O晶体。采用XRD,SEM以及紫外-可见漫反射光谱仪(UV-Vis)进行表征,探讨了Cu_(2)O骸晶的形成条件及对光催化的影响。分析认为,谷氨酸与山梨醇混合使得溶液中Cu^(2+)被大量还原为Cu^(+),溶液极度饱和,晶体边缘快速生长而晶面生长缓慢,形成了Cu_(2)O骸晶形貌,Cu_(2)O骸晶的光催化性能较光滑的八面体晶形更加优越。

关键词： Cu_(2)O 骸晶光催化晶体形貌晶体生长水热法

老年人社会参与对心理健康的影响——基于CHARLS追踪调查的发现

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中国人口科学 2023年第4期37卷 98-113页

作者：徐金燕张倩倩湖南科技大学法学与公共管理学院湖南科技大学教育学院

文章基于中国健康与养老追踪调查2011~2018年4次追踪数据,采用潜增长模型和交叉滞后效应模型,考察老年人社会参与和心理健康水平的变动轨迹及个体差异,并从动态角度探讨社会参与和老年人心理健康的相互影响。研究发现:(1)老年人社会参... 详细信息

文章基于中国健康与养老追踪调查2011~2018年4次追踪数据,采用潜增长模型和交叉滞后效应模型,考察老年人社会参与和心理健康水平的变动轨迹及个体差异,并从动态角度探讨社会参与和老年人心理健康的相互影响。研究发现:(1)老年人社会参与和抑郁情绪随时间推移呈上升趋势,并具有个体差异化特征;(2)随着社会参与的不断增长,老年人抑郁水平上升速度减缓,心理健康状态得到改善;(3)社会参与能够预防和降低老年人抑郁水平,但抑郁情绪的增长和社会参与初始水平无关,只有持续的社会参与才能延缓老年人抑郁情绪的增长。文章建议,政府部门及相关工作人员应根据老年人口异质性,制定有针对性的社会参与促进政策,完善老年人社会参与机制,增进老年人持续性参与,以提高其心理健康水平。

关键词：老年人社会参与心理健康发展轨迹

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氦气风机驱动电机转子径向通风结构研究

电机与控制学报 2024年第3期28卷 96-109页

作者：陶大军孟卓然徐金燕戈宝军哈尔滨理工大学电气工程学院黑龙江哈尔滨150080

氦气风机驱动电机是高温气冷堆一回路唯一能动设备,其安全性直接影响到高温气冷堆的安全稳定运行。针对高温高压环境及氦气传热工质对驱动电机风路结构设计及相关参数影响引发的新问题,通过建立双侧转子铁心三维风路结构流固耦合传热模... 详细信息

氦气风机驱动电机是高温气冷堆一回路唯一能动设备,其安全性直接影响到高温气冷堆的安全稳定运行。针对高温高压环境及氦气传热工质对驱动电机风路结构设计及相关参数影响引发的新问题,通过建立双侧转子铁心三维风路结构流固耦合传热模型,计算分析了高温高压环境下传热工质氦气在转子径向风沟内的流动特性,研究了转子分别在动态和静态情况下,通风结构内流体流动规律及转子铁心和导条的温升变化规律。同时,对不同种类传热工质的对应规律进行了对比研究,搭建了模拟实验测试装置,实测数据与数值计算结果吻合较好,验证了计算分析结果的合理性和正确性,为氦气风机驱动电机转子风路结构优化、冷却性能的有效提升提供一定的理论参考。

关键词：高温气冷堆氦气风机驱动电机通风结构传热特性流固耦合

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轻丰中子核的奇特结构研究进展

科学通报 2023年第9期68卷 1004-1015页

作者：楼建玲叶沿林杨再宏李奇特许金艳北京大学物理学院技术物理系北京100871 北京大学物理学院核物理与核技术国家重点实验室北京100871

不稳定核的奇特结构,例如集团结构、闯入态等,是放射性核束物理研究的热点方向之一.直接核反应实验是研究丰中子核奇特结构的重要手段之一.本课题组自主研发了适用于放射性束流在质子和氘靶上发生直接核反应实验研究的带电粒子探测阵列... 详细信息

不稳定核的奇特结构,例如集团结构、闯入态等,是放射性核束物理研究的热点方向之一.直接核反应实验是研究丰中子核奇特结构的重要手段之一.本课题组自主研发了适用于放射性束流在质子和氘靶上发生直接核反应实验研究的带电粒子探测阵列.利用该高精度、大立体角、模块化、多用途的探测阵列,我们在轻丰中子核的奇特结构实验研究方面取得了一系列重要进展:从实验上确认了^(14)C的π型线性链状分子转动带;发现了丰中子核^(16)C的π2σ2构型线性链状分子结构,^(14)C的一个共振态可能有“3α呈线性排列”的线链超形变结构.我们定量研究了^(12)Be、^(13)B等N=8附近丰中子核的s波和d波闯入强度,结果表明:^(12)Be基态中s波占19%,远远小于^(11)Be(~80%),而d波成分却高达57%,是主要的闯入成分;^(13)B基态中的s(d)波闯入成分约为12%(5%),处于从Be到C的过渡.

关键词：直接核反应集团结构闯入态不变质量缺失质量