检索结果-南通市图书馆

Hg_(0.72)Cd_(0.28)Te扫描隧道谱的模型解释

同方期刊数据库博看期刊评论

在线全文

学校读者我要写书评

暂无评论

红外与毫米波学报 2024年第3期43卷 300-304页

作者：肖正琼戴昊光刘欣扬陈平平查访星上海大学理学院物理系上海200444 中国科学院上海技术物理研究所红外物理国家重点实验室上海200083

本工作利用截面扫描隧道显微镜(XSTM)研究了分子束外延生长的Hg_(0.72)Cd_(0.28)Te薄膜。扫描隧道谱(STS)测量表明,此碲镉汞材料的电流-电压(I/V)隧道谱呈现的零电流平台宽度(隧道谱表观带隙)比其实际材料带隙增大约130%,说明存在明显... 详细信息

本工作利用截面扫描隧道显微镜(XSTM)研究了分子束外延生长的Hg_(0.72)Cd_(0.28)Te薄膜。扫描隧道谱(STS)测量表明,此碲镉汞材料的电流-电压(I/V)隧道谱呈现的零电流平台宽度(隧道谱表观带隙)比其实际材料带隙增大约130%,说明存在明显的针尖诱导能带弯曲(TIBB)效应。扫描隧道谱三维TIBB模型计算发现低成像偏压测量时获取的I/V隧道谱数据与理论计算结果有令人满意的一致性。然而较大成像偏压时所计算的I/V谱与实验谱线在较大正偏压区域存在一定偏离。这是目前的TIBB模型未考虑带带隧穿、缺陷辅助隧穿等碲镉汞本身的输运机制对隧道电流的影响造成的。

关键词：扫描隧道显微镜扫描隧道谱 HgCdTe 针尖诱导能带弯曲

Recrystallization texture development in rare-earth(RE)-doped non-oriented silicon steel

在线全文

学校读者我要写书评

暂无评论

Journal of Iron and Steel Research International 2020年第11期27卷 1339-1346页

作者： Zheng-hua He Yu-hui Sha Yong-kuang Gao Song-tao Chang fang zha Liang Zuo Key Laboratory for Anisotropy and Texture of Materials(Ministry of Education) Northeastern UniversityShenyang 110819Liaoning.China

High-grade non-oriented silicon steel with higher permeability and lower core loss has become the pursed target with the rapid developnient of electrical *** effects of rare-earth(RE)element on recrystallization texture in RE-doped Fe-3.1 wt.%Si-1.2 wt.%Al non-oriented silicon steel were investigated by macro-and micro-texture *** variation of recrystallization texture with RE element content was *** the competition among main recrystallization texture components,favorable{113}and X fiber(//ND)are strengthened and unfavorable y fiber is evidently decreased by the addition of RE element,whereas the effect of RE element is reversed by excess RE *** recrystallization texture development is determined by RE-affected nucleation and grain growth in terms of grain boundary migration related to segregation and *** properly inhibited grain boundary mobility can promote favorable recrystallization texture by the improved nucleation and efficient grain growth.

关键词： Non-oriented silicon steel Texture Rare-earth element Grain boundary Segregation

Hydrosilylation of olefins over rhodium complex anchored over thioether-functionalized MCM-41

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Chemical Letters 2010年第11期21卷 1310-1313页

作者： Lig fang zha,Wei Sen Yang,Wen Yan Hao,Ming Zhong Cai Department of Chemistry,Jiangxi Normal University,Nanchang 330022,China Department of Chemistry Jiangxi Normal University Nanchang 330022 China

The hydrosilylation of alkenes with triethoxysilane has been achieved at 120 C in the presence of 0.01 mol%of thioetherfunctionalized MCM-41 anchored rhodium complex,affording the corresponding addition products in 68-91%*** supported rhodium complex can be reused several times without noticeable loss of *** system not only solves the basic problems of catalyst separation and recovery,but also avoids the use of phosphine ligands.

关键词： Supported rhodium catalyst Sulfur rhodium complex Hydrosilylation MCM-41 Heterogeneous catalysis

Risk factors for postpartum posttraumatic stress disorder after emergency admission

在线全文

学校读者我要写书评

暂无评论

World Journal of Emergency Medicine 2024年第2期15卷 121-125页

作者： Fengxia Du Jun zha Yan Li Lichao fang Shuyu Xia Youjia Yu Department of Obstetrics Suzhou Xiangcheng People’s HospitalSuzhou 215131China Department of Anesthesiology the Second Affiliated Hospital of Wannan Medical CollegeWuhu 241000China Department of Anesthesiology Suzhou Xiangcheng People’s HospitalSuzhou 215131China Department of Emergency and Intensive Care Unit Suzhou Xiangcheng People’s HospitalSuzhou 215131China

BACKGROUND:Postpartum posttraumatic stress disorder(PTSD)can occur in women who give birth after emergency *** identification of risk factors for this condition is crucial for developing effective preventive *** retrospective study aimed to explore the incidence and risk factors for postpartum PTSD in women who give birth after emergency ***:Medical records of women who gave birth after emergency admission were collected between March 2021 and April *** patients’general conditions and perinatal clinical indicators were *** puerperae were divided into PTSD group and control group based on symptom occurrence at six weeks *** logistic regression analysis was performed to identify risk ***:A total of 276 puerperae were included,with a PTSD incidence of 20.3% at six weeks *** logistic regression analysis identified emergency cesarean section(odds ratio[OR]=2.102;95%confidence interval[CI]:1.114-3.966,P=0.022),admission to the emergency department after midnight(12:00 AM)(OR=2.245;95%CI:1.170-4.305,P<0.001),and cervical dilation(OR=3.203;95%CI:1.670–6.141,P=0.039)as independent risk factors for postpartum *** pump use(OR=0.500;95%CI:0.259–0.966,P=0.015)was found to be a protective factor against postpartum ***:Emergency cesarean section,admission to the emergency department after midnight,and cervical dilation were identified as independent risk factors for postpartum PTSD,while analgesic pump use was a protective *** findings provide insights for developing more effective preventive measures for women who give birth after emergency admission.

关键词： Risk factors Posttraumatic stress disorder Emergency Delivery

A compact X-band backward traveling-wave accelerating structure

在线全文

学校读者我要写书评

暂无评论

Nuclear Science and Techniques 2024年第5期35卷 13-29页

作者： Xian-Cai Lin Hao zha Jia-Ru Shi Qiang Gao fang-Jun Hu Qing-Zhu Li Huai-Bi Chen Department of Engineering Physics Tsinghua UniversityBeijing 100084China Key Laboratory of Particle and Radiation Imaging(Tsinghua University) Ministry of EducationBeijing 100084China

Very high-energy electrons(VHEEs)are potential candidates for FLASH radiotherapy for deep-seated *** proposed a compact VHEE facility based on an X-band high-gradient high-power *** this study,we investigated and realized the first X-band backward traveling-wave(BTW)accelerating structure as the buncher for a VHEE facility.A method for calculating the parameters of single cell from the field distribution was introduced to simplify the design of the BTW ***-domain circuit equations were applied to calculate the transient beam parameters of the buncher in the unsteady state.A prototype of the BTW structure with a thermionic cathode-diode electron gun was designed,fabricated,and tested at high power at the Tsinghua X-band high-power test *** structure successfully operated with 5-MW microwave pulses from the pulse compressor and outputted electron bunches with an energy of 8 MeV and a pulsed current of 108 mA.

关键词： Backward traveling-wave accelerating structure Equivalent circuit model High-power test Very high-energy electron radiotherapy

超高真空扫描隧道谱实验对碲镉汞室温带隙的直接测定

在线全文

学校读者我要写书评

暂无评论

红外与毫米波学报 2013年第2期32卷 145-149页

作者：任秀荣查访星上海大学理学院物理系和微结构实验室上海200444 中科院上海技术物理研究所红外物理国家重点实验室上海200083

利用超高真空扫描隧道显微镜的隧道谱实验对汞空位掺杂的液相外延P型碲镉汞材料在室温条件下进行测量,发现直接的电流-电压隧道谱对带隙预言一定程度上要受到成像偏置电压的影响.但当采用了锁相放大测量技术,通过实验直接获取微分隧道谱... 详细信息

利用超高真空扫描隧道显微镜的隧道谱实验对汞空位掺杂的液相外延P型碲镉汞材料在室温条件下进行测量,发现直接的电流-电压隧道谱对带隙预言一定程度上要受到成像偏置电压的影响.但当采用了锁相放大测量技术,通过实验直接获取微分隧道谱(dI/dV)信号,并利用电流-电压谱对dI/dV作归一化处理时,最终结果则能较准确、可靠地预言材料的带隙,表明扫描隧道谱方法作为独立于光学方法之外的另一种实验表征手段对碲镉汞能带电子结构研究的适用性.

关键词：碲镉汞扫描隧道显微镜扫描隧道谱能带带隙锁相放大技术

在线全文

学校读者我要写书评

暂无评论

环境水样中痕量肼的分析方法研究

中国环境监测 2007年第6期23卷 16-17页

作者：赵芳石河子大学化学化工学院新疆石河子832000

报道一种微量测定环境水样中痕量肼的新方法。该方法基于在氢氧化钠碱性介质中高锰酸钾直接氧化肼的化学发光现象,建立了微量肼的流动注射化学发光分析方法。该方法线性范围为1.0×10^-9～8.0×10^-5g/ml,检出限3.6×10^-10g/ml,对1.0×... 详细信息

报道一种微量测定环境水样中痕量肼的新方法。该方法基于在氢氧化钠碱性介质中高锰酸钾直接氧化肼的化学发光现象,建立了微量肼的流动注射化学发光分析方法。该方法线性范围为1.0×10^-9～8.0×10^-5g/ml,检出限3.6×10^-10g/ml,对1.0×10^-8g/ml的肼连续11次测定的相对标准偏差为2.1%,该方法已成功用于环境水样中痕量肼的测定。

关键词：化学发光流动注射肼