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黄河矿—中华铈矿系列稀土矿物的多体性特征

中国稀土学报 1998年第2期16卷 97-100页

作者：杨主明陶克捷张培善中国科学院地质研究所

采用结晶学模块法研究了黄河矿（ＣｅＢａ（ＣＯ３）２Ｆ），中华铈矿（ＣｅＢａ２（ＣＯ３）３Ｆ）和氟碳铈钡矿（Ｃｅ２Ｂａ３（ＣＯ３）５Ｆ２）的晶体结构。三种矿物的晶体结构中存在五种相同的配位多面体及其单链。多面体链相互联... 详细信息

采用结晶学模块法研究了黄河矿（ＣｅＢａ（ＣＯ３）２Ｆ），中华铈矿（ＣｅＢａ２（ＣＯ３）３Ｆ）和氟碳铈钡矿（Ｃｅ２Ｂａ３（ＣＯ３）５Ｆ２）的晶体结构。三种矿物的晶体结构中存在五种相同的配位多面体及其单链。多面体链相互联接组成两种似层状模块（Ｈ）和（Ｚ）。黄河矿和中华铈矿的晶体结构分别由似层状模块（Ｈ）和（Ｚ）构筑而成，氟碳铈钡矿则由这两种模块的交替堆垛形成。根据多体模型三种矿物的结构可分别用（ＨＨ）、（Ｚ）和（ＨＺＨＺ）表示，（Ｚ）和（Ｈ）模块均具有１／２ｂ位移。借助多体模型可解释该系列矿物结构的堆垛无序和预测新多体矿物。

关键词：黄河矿中华铈矿氟碳铈钡矿稀土矿晶体结构

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基于GIS的闪电参数查询系统设计与实现

南京信息工程大学学报（自然科学版） 2018年第4期10卷 514-520页

作者：成勤王清龙肖稳安刘云鹏徐海舟张科杰宜昌市气象局宜昌443000 南京信息工程大学大气物理学院南京210044 中海石油(中国)有限公司崖城作业公司深圳518000 湖北省防雷中心武汉430074

基于.NET4.0开发环境、MapX5.0组件技术和SQL Server数据库开发与应用技术,利用C#编程语言,设计了闪电参数可视化查询系统.该系统将闪电定位资料与地理信息相结合,实现了地理信息的查询和编辑、原始闪电数据的存储和管理、闪电参数的查... 详细信息

基于.NET4.0开发环境、MapX5.0组件技术和SQL Server数据库开发与应用技术,利用C#编程语言,设计了闪电参数可视化查询系统.该系统将闪电定位资料与地理信息相结合,实现了地理信息的查询和编辑、原始闪电数据的存储和管理、闪电参数的查询和分析、专题图绘制和输出等功能.以武汉"1+8"城市圈(武汉市、孝感市、天门市、潜江市、仙桃市、咸宁市、鄂州市、黄石市、黄冈市)为例,展示了闪电参数查询、专题图绘制、测量工具和闪电发生位置以及雷电流强度分布查询的应用结果.

关键词：地理信息系统(GIS) MapX技术闪电参数

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硬膜外穿刺中应用咪达唑仑的临床观察

首都医科大学学报 2003年第3期24卷 326-328页

作者：王春梅王克杰张建李建新首都医科大学宣武医院麻醉科宣武医院胸外科

为观察硬膜外穿刺前应用国产咪达唑仑注射液的最适剂量 ,选择 1 5 0例病人随机双盲分成 5组 ,每组 3 0人。第 1组为对照组 ,第 2、3、4、5组分别静脉注射咪达唑仑注射液 0 .0 2、0 .0 4、0 .0 6、0 .0 8mg/kg。观察平均动脉压、心率、... 详细信息

为观察硬膜外穿刺前应用国产咪达唑仑注射液的最适剂量 ,选择 1 5 0例病人随机双盲分成 5组 ,每组 3 0人。第 1组为对照组 ,第 2、3、4、5组分别静脉注射咪达唑仑注射液 0 .0 2、0 .0 4、0 .0 6、0 .0 8mg/kg。观察平均动脉压、心率、呼吸、血氧饱和度、记忆及镇静程度的变化。第 1、2组硬膜外穿刺操作后平均动脉压增加 2 .3kPa、心率平均增加 1 1次 /min ,第 1、2组间无差异 ;且 2组用药前后平均动脉压与心率无差异 ;第 3组操作前后和用药前后平均动脉压、心率均无显著差异。用药后与用药前相比 ,第 4、5组平均动脉压下降 ,心率减慢 ,但均在正常范围 ;用药后组间平均动脉压与心率无差异。呼吸及血氧饱和度各组均在正常范围。第 1、2、3、4、5组记忆率分别为 1 0 0 %、87%、40 %、1 7%及 0 ,用药后均有顺行性遗忘作用 ,第 3、4组顺行性遗忘作用强。镇静程度 :第 1～ 4组均为清醒或入睡可唤醒 ,第 5组有 9例病人入睡唤醒困难但睫毛反射存在 ,用药后第 2、3、4组患者均可主动配合操作 ,第 5组有少数病人不能主动配合。提示 :硬膜外穿刺前静脉注射 0 .0 4～ 0 .0 6mg/kg咪达唑仑可稳定生命体征 ,消除对不良刺激的记忆 ,且患者可主动配合操作 ,因此。

关键词：硬膜外穿刺咪达唑仑硬膜外麻醉血氧饱和度应激反应

Dispersion characteristics of switching transients from large‐scale experiments in a 1100 kV gas insulated switchgear circuit

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High Voltage 2023年第6期8卷 1253-1263页

作者： Zihan Teng Weijiang Chen Jiangong zhang Baoquan Wan Jun Zhao kejie Li Zhenghai Liao Zheyuan Gan State Key Laboratory of Power Grid Environmental Protection China Electric Power Research InstituteWuhanChina State Grid Corporation of China BeijingChina School of Electrical Engineering and Automation Hefei University of TechnologyHefeiChina

The switching operation of gas insulated switchgear(GIS)disconnector will produce multiple random spark discharges between the gas gaps of the *** spark discharge can be affected by various random factors,such as trapped charge on the load side,the initial operating phase,gap distance and operating speed of the disconnector,leading to dispersion *** present,some studies have mentioned this dispersion,but its impact is still unclear due to the lack of experimental data,resulting in a deviation between the simulation results and the measured *** this study,thousands of switching operations were carried out based on the 1100 kV full‐scale GIS circuit in Wuhan ultra‐high voltage alternating current Test *** maximal information coeffi-cient analysis,linear regression fitting and other statistical methods were used to discuss the dispersion characteristics of very fast transient overvoltage(VFTO)and transient enclosure voltage(TEV)from large‐scale experimental *** results show that the dispersion of VFTO and TEV in amplitude aspects both increase gradually as the breakdown voltage increases,with the maximum difference of five times of TEV amplitude at normalised breakdown *** terms of frequency characteristics,the dispersion of different fre-quency components in TEV is always greater than that of VFTO,especially for the high‐frequency ***,by comparing the frequency characteristics of TEV at different positions,we notice that the dispersion is almost independent of the spatial po-sition but only determined by the randomness of spark *** discoveries reveal the importance of the dispersion in switching transients and make up for the lack of theoretical understanding of the correlation among them.

关键词： characteristics transient breakdown

Effects of yttrium on microstructure and mechanical properties of Mg-6Al magnesium alloy

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China Foundry 2010年第4期7卷 362-366页

作者： Ren Wenliang Li Quan＇an Li Jianhong Li kejie zhang Xingyuan School of Material Science and Engineering Henan University of Science and Technology Luoyang 471003 China School of Material Science and Engineering Xi＇an University of Technology Xi＇an 710048 China

Since Y has a great solid solubility in magnesium alloys, it helps enhancing the heat-resistant property of magnesium alloys. The effects of Y on microstructures and mechanical properties of Mg-6Al alloy have been studied in this work. The results show that Y addition refines grains of Mg-6Al alloy, and reduces the amount of the Mg 17 Al 12 phase. At the same time, the high melting-point Al 2 Y phase particles are formed. According to the mathematical model of the two-dimensional lattice misfit proposed by Braffit, it is believed that the Al 2 Y particles can serve as the nucleation sites for α-Mg. After T6 treatment, both elongation and ultimate tensile strength of Mg-6Al alloy at the room temperature and high-temperature increased firstly and then decreased, with increasing Y addition. The peak mechanical properties were achieved in the Mg-6Al-1.2Y alloy system. Y addition appears to change the fracture characteristic of Mg-6Al alloy. With 1.2wt%Y, the fracture surface of the alloy showed a lot of dimples and tearing ridges which connected the microscopic dimples and the fracture is mixed fracture of quasi-cleavage and ductile fracture.

关键词： yttrium Mg-6Al alloy microstructure mechanical properties

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琼东南陵水凹陷北坡构造特征及构造演化分析

海洋石油 2024年第3期44卷 31-38页

作者：王旖旎张百涛王允洪金可洁中国石油化工股份有限公司上海海洋油气分公司勘探开发研究院上海200120

为了实现陵水凹陷北坡大型气田的勘探突破,利用钻井、三维地震资料,基于盆地构造解析及平衡剖面技术,综合分析构造格局及断裂体系特征,剖析其与油气成藏的关系。研究表明,构造样式以伸展为主、右行走滑为辅,构造演化分为四期:(1)断陷期... 详细信息

为了实现陵水凹陷北坡大型气田的勘探突破,利用钻井、三维地震资料,基于盆地构造解析及平衡剖面技术,综合分析构造格局及断裂体系特征,剖析其与油气成藏的关系。研究表明,构造样式以伸展为主、右行走滑为辅,构造演化分为四期:(1)断陷期(始新世-渐新世),断裂全区发育,活动强烈;(2)断拗期(早中新世),伸展作用减弱,断裂数量减少;(3)拗陷缓慢沉降期(中中新世),开始发育“陆架-陆坡-深海平原”构造格局,控凹断裂持续发育;(4)拗陷加速沉降期(上新世-第四纪),扩张作用减弱,南部右行张扭断裂带开始活动。隆凹相间的构造格局及断裂体系控制西部陡坡带生烃强度大,断砂配置好,东部缓坡带烃源薄,断阶输导差异成藏。提出西部F2-2断裂下降盘为下一步有利勘探区带,为陵水凹陷油气勘探奠定良好基础。

关键词：琼东南盆地陵水凹陷北坡构造特征构造演化

Waterproof of rock joint with lead strip for splitting tuff sheet in ancient China quarrying caverns

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Science China(Technological Sciences) 2012年第4期55卷 960-969页

作者： YANG ZhiFa zhang LuQing YUE ZhongQi zhang ZhongJian YANG TianYao LIN XianJian TAO kejie ZHU JieWang Key Laboratory of Engineering Geomechanics Institute of Geology and Geophysics Chinese Academy of Sciences Beijing 100029 China Department of Civil Engineering University ofHong Kong Hong Kong China Shepandao Hotspring Resort Co. Ltd. Sanmen 317100 China State Key Laboratory of Lithospheric Evolution Institute of Geology and Geophysics Chinese Academy of Sciences Beijing 100029 China Civil Engineering Institute Shandong Construction University Jinan 250001 China

This paper presents the relics of rock joints caulked with lead strips, unearthed by the authors in 2007 and 2008. The relics were in ancient quarry caverns in Shepan Island, Zhejiang Province, eastern China. The quarry activities were mainly carried out for production of regular tuff stone plates about 800 years ago. Each of the lead strips was sealed into a rock joint by punching manually and carefully. At present, the lead strips still contact tightly with the rock joints and new mineral cerussite is found to have formed at the contact surfaces between the lead strip and its caulked rock joint. The use of lead strips caulking rock joints in quarry caverns is found for prevention of water from seeping out of the country rocks into quarry cavern bases, where all of the in-situ intact tuff rock was manually and near-horizontally split into thin rock sheets one by one for production of regular tuff plates. Furthermore, it is found that the tensile splitting of tuff sheets at the cavern base required the intact rocks at the cavern base had to be dry. Through this horizontal base splitting for tuff sheets from the top to the bottom, a dome-shape interior space was formed for each rock cavern with the near horizontal imprints of thin sheet layers permanently on the sidewalls.

关键词： rock cavern lead strips sealant joints waterproof tuff splitting quarry

Oil‐paper insulation partial discharge ultrasonic multifrequency sensing array based on fibre‐optic Fabry-Perot sensor

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High Voltage 2022年第2期7卷 325-335页

作者： Zhixian zhang Jiali Lei Weigen Chen Tianhe Yang Yuxuan Song kejie Wu Fan Liu State Key Laboratory of Power Transmission Equipment&System Security and New Technology Chongqing UniversityChongqingChina State Grid Hubei Electric Power Research Institute WuhanHubeiChina

In order to improve the sensitivity and accuracy of oil‐paper insulation partial discharge detection by the fibre‐optic Fabry-Perot(FP)ultrasonic sensor,this work studied the ultrasonic signal’s frequency characteristics of typical oil‐paper insulation partial dis-charges and the vibration characteristics of the FP sensor’s diaphragm in the liquid *** on the works above,a multifrequency FP sensor array is proposed,consisting of several FP sensors with different resonant frequencies to detect partial *** experimental results show that the liquid environment has a significant effect on the vibration characteristics of the FP sensor’s diaphragm,and the sensitivity and accuracy of partial discharge detection can be improved based on the multifrequency FP sensing array,which can also be applied in the pattern recognition and localisation of partial discharges.

关键词： insulation fibre sensor

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面向微纳遥感星座构建的阻力差分控制方法

航天器工程 2024年第1期33卷 11-18页

作者：张国云龚轲杰何雨帆陈军蔡立锋王超马腾贺于珍西安卫星测控中心西安710043

基于整星质量、功耗、体积和成本考虑,一些微纳卫星通常不加装推进系统。为满足这类微纳遥感卫星构建星座的要求,提出采用阻力差分控制(无动力控制)技术实现星座构建的方法。通过调整太阳翼迎风面积,利用星间阻力差增大或减小2颗卫星轨... 详细信息

基于整星质量、功耗、体积和成本考虑,一些微纳卫星通常不加装推进系统。为满足这类微纳遥感卫星构建星座的要求,提出采用阻力差分控制(无动力控制)技术实现星座构建的方法。通过调整太阳翼迎风面积,利用星间阻力差增大或减小2颗卫星轨道半长轴之差,在不改变卫星飞行姿态、不影响有效载荷应用的情况下实现微纳遥感星座相位控制。利用20颗微纳遥感卫星构建星座对阻力差分控制方法进行验证,结果表明:将阻力差分控制技术应用于微纳遥感星座相位控制,能顺利完成微纳遥感卫星同一轨道面的等相位部署,并成功实现星座构建。

关键词：微纳遥感星座阻力差分控制相位控制