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Active tectonic blocks and strong earthquakes in the continent of China 被引量:262
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作者 ZHANG Peizhen (张培震) DENG Qidong (邓起东) ZHANG Guomin (张国民) MA Jin (马 瑾) GAN Weijun (甘卫军) MIN Wei (闵 伟) MAO Fengying (毛凤英) WANG Qi (王 琪) 《Science China Earth Sciences》 SCIE EI CAS 2003年第z2期13-24,共12页
The primary pattern of the late Cenozoic to the present tectonic deformation of China is characterized by relative movements and interactions of tectonic blocks. Active tectonic blocks are geological units that have b... The primary pattern of the late Cenozoic to the present tectonic deformation of China is characterized by relative movements and interactions of tectonic blocks. Active tectonic blocks are geological units that have been separated from each other by active tectonic zones. Boundaries between blocks are the highest gradient of differential movement. Most of tectonic activity occurs on boundaries of the blocks. Earthquakes are results of abrupt releases of accumulated strain energy that reaches the threshold of strength of the earth's crust. Boundaries of tectonic blocks are the locations of most discontinuous deformation and highest gradient of stress accumulation, thus are the most likely places for strain energy accumulation and releases, and in turn, devastating earthquakes. Almost all earthquakes of magnitude greater than 8 and 80%-90% of earthquakes of magnitude over 7 occur along boundaries of active tectonic blocks. This fact indicates that differential movements and interactions of active tectonic blocks are the primary mechanism for the occurrences of devastating earthquakes. 展开更多
关键词 active TECTONIC block interactions of blocks differential movement STRONG EARTHQUAKE activity.
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Pattern of latest tectonic motion and its dynamics for active blocks in Sichuan-Yunnan region, China 被引量:138
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作者 XU Xiwei (徐锡伟) WEN Xueze (闻学泽) ZHENG Rongzhang (郑荣章) MA Wentao (马文涛) SONG Fangming (宋方敏) YU Guihua (于贵华) 《Science China Earth Sciences》 SCIE EI CAS 2003年第z2期210-226,共10页
Based on the concept of "active blocks" and spatial distribution of historical earthquakes with surface ruptures as well as major and subordinate active faults. The Sichuan-Yunnan region can be divided into ... Based on the concept of "active blocks" and spatial distribution of historical earthquakes with surface ruptures as well as major and subordinate active faults. The Sichuan-Yunnan region can be divided into four first-order blocks. They are the Markam block (I), the Sichuan-Yunnan rhombic block (II), Baoshan-Pu'er block (III), and Mizhina-Ximeng block (IV). Cut by sub-ordinate NE-trending active faults, the Sichuan-Yunnan rhombic block (II) can be further divided into two sub-blocks: the northwestern Sichuan sub-block (II1) and the middle Yunnan sub-block (II2), while the Baoshan- Pu'er block (III) can be further divided into three sub-blocks: Baoshan sub-block (III1), Jinggu sub-block (III2), and Mengla sub-block (III3). A quantitative study of offset landforms is carried out and the basic types of active faults and their long-term slip rates along the major boundaries of active blocks of different orders in the Sichuan-Yunnan region are determined, through slip vector analysis, the motion states of the active blocks are clarified and the deformation coordination on the block margins is discussed. It is suggested that the tectonic motion of the blocks in this region is a complex or superimposition of three basic types of motions: southeastward sliding, rotating on vertical axis, and uplifting. The Markam block (I), the northwestern Sichuan sub-block (II1), and middle Yunnan sub-block (II2) have a southeastward horizontal sliding rate of 1-5 mm/a, clockwise rotating angular rate of 1.4-4(/Ma, and uplifting rate of about 1 mm/a. The Baoshan-Pu'er (III) and Mizhina-Ximeng (IV) blocks have also been extensively clockwise rotated. This pattern of motion is a strain response to the collision between the Indian and Eurasian plates and the localized deformation and differential slip on the block margins associated with the northward motion of the Indian Plate. Because a set of transverse thrusts between the blocks absorbs and transforms some components of eastward or southeastward sliding motion, the eastward escape or 展开更多
关键词 Sichuan-Yunnan region active fault active block BLOCK rotation TECTONIC motion.
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电网对称故障下基于active crowbar双馈发电机控制 被引量:91
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作者 张学广 徐殿国 《电机与控制学报》 EI CSCD 北大核心 2009年第1期99-103,共5页
随着风力发电规模和风电机组单机容量不断增大,要求大型风电机组具有低电压穿越能力,因此需要研究三相对称故障下双馈风力发电机控制方法。在电网电压突然跌落时,由于双馈发电机中的电磁耦合关系,在定转子中感应出过电压过电流,为保护... 随着风力发电规模和风电机组单机容量不断增大,要求大型风电机组具有低电压穿越能力,因此需要研究三相对称故障下双馈风力发电机控制方法。在电网电压突然跌落时,由于双馈发电机中的电磁耦合关系,在定转子中感应出过电压过电流,为保护转子侧变换器,需要通过crowbar来短路双馈发电机的转子。针对传统的passive crowbar的不足,采用active crowbar电路的控制方法。当电网故障造成双馈发电机转子过流时,开启active crowbar电路来旁路转子侧变换器。当转子电流下降到一定程度时断开crowbar,转子侧变换器恢复工作,此时双馈电机可以向电网同时提供有功无功支持。理论分析的基础上进行了仿真研究。仿真结果证实了采用active crowbar可以有效地实现双馈风力发电机的低电压穿越。 展开更多
关键词 双馈发电机 对称故障 风力发电 active CROWBAR 低电压穿越
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有源电子式电流互感器中高压侧电路的供能方法 被引量:75
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作者 钱政 《高压电器》 CAS CSCD 北大核心 2004年第2期135-138,共4页
电子式电流互感器已经成了国内外研究的热点,其中有源电子式互感器高压侧电路的供能问题则是研究工作中的关键技术。笔者首先简要地综述了电子式电流互感器的发展,然后重点介绍有源电子式电流互感器中高压侧电路的供电问题,对国内外的... 电子式电流互感器已经成了国内外研究的热点,其中有源电子式互感器高压侧电路的供能问题则是研究工作中的关键技术。笔者首先简要地综述了电子式电流互感器的发展,然后重点介绍有源电子式电流互感器中高压侧电路的供电问题,对国内外的研究现状进行了探讨,得到了一些有益的结论。 展开更多
关键词 有源电子式电流互感器 高压侧电路 供能方法 光学传感原理
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Five hundred meter aperture spherical radio telescope (FAST) 被引量:81
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作者 NAN Rendong 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS 2006年第2期129-148,共20页
Five hundred meter aperture spherical radio telescope (FAST) will be the largest radio telescope in the world. The innovative engineering concept and design pave a new road to realizing a huge single dish in the most ... Five hundred meter aperture spherical radio telescope (FAST) will be the largest radio telescope in the world. The innovative engineering concept and design pave a new road to realizing a huge single dish in the most effective way. Three outstanding features of the telescope are the unique karst depressions as the sites, the active main reflector which corrects spherical aberration on the ground to achieve full polarization and a wide band without involving a complex feed system, and the light focus cabin driven by cables and servomechanism plus a parallel robot as secondary adjustable system to carry the most precise parts of the receivers. Being the most sensitive radio telescope, FAST will enable astronomers to jumpstart many of the science goals, for example, the neutral hydrogen line surveying in distant galaxies out to very large redshifts, looking for the first shining star, detecting thousands of new pulsars, etc. Extremely interesting and exotic objects may yet await discovery by FAST. As a multi-science platform, the telescope will provide treasures to astronomers, as well as bring prosperity to other research, e.g. space weather study, deep space exploration and national security. The construction of FAST itself is expected to promote the development in high technology of relevant fields. 展开更多
关键词 RADIO ASTRONOMY RADIO TELESCOPE active reflector.
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水质模型与地理信息系统的集成研究 被引量:50
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作者 张行南 耿庆斋 逄勇 《水利学报》 EI CSCD 北大核心 2004年第1期90-94,共5页
水质模型是水体污染物迁移转化模拟的主要工具,在水环境保护、水污染防治等领域得到了广泛的应用。本文在地理信息系统平台上,利用其强大的空间数据分析能力,研制了水质模拟软件系统。系统包括了水质模型输入数据的处理,实时模型计算,... 水质模型是水体污染物迁移转化模拟的主要工具,在水环境保护、水污染防治等领域得到了广泛的应用。本文在地理信息系统平台上,利用其强大的空间数据分析能力,研制了水质模拟软件系统。系统包括了水质模型输入数据的处理,实时模型计算,及模拟结果的可视化输出。该系统缩短了模型建模周期,提高了模型运行的效率。系统界面及模拟结果的表达美观,操作方便。该系统在江苏省水环境容量信息管理系统的应用中取得了较好效果。 展开更多
关键词 水质模型 地理信息系统 有限元 active x控件
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CATIA V5二次开发技术探讨 被引量:55
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作者 龙峰 樊留群 《淮阴工学院学报》 CAS 2005年第5期21-23,27,共4页
介绍了CATIAActiveXAutomation组件对象模型原理与结构以及其在CATIA二次开发中的作用;然后比较了CATIA二次开发技术的两次方式:CAAC++技术和CAAAUTOMATION技术,两种方式各有优劣,并分别在两种开发环境(VisualC++和VisualBasic)中通过利... 介绍了CATIAActiveXAutomation组件对象模型原理与结构以及其在CATIA二次开发中的作用;然后比较了CATIA二次开发技术的两次方式:CAAC++技术和CAAAUTOMATION技术,两种方式各有优劣,并分别在两种开发环境(VisualC++和VisualBasic)中通过利用Automation接口实现引用类型库程序以及与CATIA的通信程序,并给出了部分代码;最后给出一个端拾器的装配设计效果。 展开更多
关键词 CATIA V5 active AUTOMATION 组件对象模型
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原因不明习惯性流产患者主动免疫治疗前后T辅助细胞1、2型细胞因子的变化 被引量:55
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作者 邱丽华 林其德 +2 位作者 洪燕 李东至 丁传伟 《中华妇产科杂志》 CAS CSCD 北大核心 2001年第7期408-410,共3页
目的 探讨原因不明习惯性流产 (UHA)患者主动免疫治疗前后血清T辅助细胞 (TH) 1/TH2型细胞因子的变化。方法 采用酶联免疫吸附法检测 3 0例正常非妊娠妇女 (正常非孕组 )、3 0例正常妊娠妇女 (正常妊娠组 )和 3 3例UHA患者 (流产组 )... 目的 探讨原因不明习惯性流产 (UHA)患者主动免疫治疗前后血清T辅助细胞 (TH) 1/TH2型细胞因子的变化。方法 采用酶联免疫吸附法检测 3 0例正常非妊娠妇女 (正常非孕组 )、3 0例正常妊娠妇女 (正常妊娠组 )和 3 3例UHA患者 (流产组 )淋巴细胞主动免疫治疗前后血清TH1型细胞因子 [白细胞介素 (IL) 2、IL 12、γ干扰素 ]和TH2型细胞因子 (IL 4、IL 10、转化生长因子β1)水平。 结果( 1)流产组治疗前血清IL 2、IL 12的水平分别为 ( 13 3± 13 8)ng/L、( 5 0 5± 2 5 8)ng/L ,明显高于正常非孕组的 ( 4 6± 6 4 )ng/L、( 2 0 3± 2 8 2 )ng/L(P <0 0 1) ;IL 4、IL 10的水平分别为 ( 13 8± 1 0 )ng/L、( 13 5± 0 7)ng/L ,明显低于正常非孕组的 ( 14 5± 1 2 )ng/L、( 14 9± 2 4 )ng/L(P <0 0 1) ;γ干扰素、转化生长因子 β1的水平分别为 ( 4 5 4± 10 4 8)ng/L、( 3 1 8± 2 6 6) μg/L ,与正常非孕组的 ( 15 2±3 6)ng/L、( 3 0 3± 2 7 9) μg/L比较 ,差异无显著性 (P >0 0 5 )。 ( 2 )流产组治疗后血清IL 2 [( 5 6±9 0 )ng/L]、IL 12 [( 2 8 5± 4 0 3 )ng/L]水平 ,较治疗前明显降低 (P <0 0 1) ;IL 4 [( 14 7± 1 2 )ng/L]、IL 10 ( 15 0± 1 8)ng/L]水平 。 展开更多
关键词 习惯性流产 免疫疗法 TH1细胞 TH2细胞 细胞活素类
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北京市儿童乙型肝炎疫苗接种12年后免疫效果观察 被引量:58
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作者 龚晓红 王富珍 +7 位作者 李辉 刘立荣 李阳桦 王宝兰 李立琴 张震 韩庆英 唐耀武 《中华预防医学杂志》 CAS CSCD 北大核心 2005年第4期265-268,共4页
目的评价北京市儿童乙型肝炎(乙肝)疫苗接种12年后的免疫效果。方法2003年1至3月采取多阶段整群系统抽样方法在1991至2000年出生后接种乙肝疫苗的儿童中抽取2491人,用固相放射免疫法检测血清HBsAg、抗HBs和抗HBc水平,并对免疫后HBsAg阳... 目的评价北京市儿童乙型肝炎(乙肝)疫苗接种12年后的免疫效果。方法2003年1至3月采取多阶段整群系统抽样方法在1991至2000年出生后接种乙肝疫苗的儿童中抽取2491人,用固相放射免疫法检测血清HBsAg、抗HBs和抗HBc水平,并对免疫后HBsAg阳性的原因进行分析。结果2491名3~12岁儿童中HBsAg阳性率为0.52%,疫苗免疫保护率为88.45%(95%CI为65.67%~97.89%),抗HBc阳性率为2.21%,各年龄组比较差异无统计学意义。接种重组(酵母)疫苗的3~6岁儿童,其抗HBs平均阳性率为38.79%,但随年龄增大抗体阳性率明显下降;几何平均滴度为52.83mIU/ml,各年龄组比较差异无统计学意义。接种乙肝血源性疫苗的6~12岁儿童,其抗HBs平均阳性率为50.79%,几何平均滴度为61.51mIU/ml,各年龄组抗体阳性率和几何平均滴度比较差异均无统计学意义。在13例HBsAg阳性儿童中,约50%儿童的母亲为HBsAg阳性。结论北京市儿童乙肝疫苗接种计划实施12年后,免疫人群保护效果理想,HBsAg阳性率未随免疫时间延长而明显增加。目前尚不需进行加强免疫,但重组(酵母)疫苗接种后抗HBs阳性率随年龄增长而显著下降,应加强血清学监测。儿童接种后成为HBsAg携带者的主要原因为母婴垂直传播。 展开更多
关键词 乙型肝炎 免疫效果观察 北京市 HBSAG阳性率 几何平均滴度 抗-HBc阳性率 抗-HBS阳性率 HBsAg携带者 重组(酵母) 血清HBSAG 抗体阳性率 各年龄组 乙肝疫苗接种 母婴垂直传播 2岁儿童 2000年 2003年 免疫法检测 免疫保护率
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ECA规则的模型和行为特定理论 被引量:35
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作者 姜跃平 汪卫 +1 位作者 施伯乐 董继润 《软件学报》 EI CSCD 北大核心 1997年第3期190-196,共7页
本文给出了ECA规则系统的一般性模型,通过扩展系统状态和改变的定义,形式化地描述了规则处理的语义,并着重研究规则系统的行为特征(可终止性和行为一致性).
关键词 数据库 规则模型 行为
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Estimation of Net Primary Productivity of Terrestrial Vegetation in China by Remote Sensing 被引量:31
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作者 陈利军 刘高焕 冯险峰 《Acta Botanica Sinica》 CSCD 2001年第11期1191-1198,共8页
Among the many approaches for studying the net primary productivity (NPP), a new method by using remote sensing was introduced in this paper. With spectral information source (the visible band, near infrared band and ... Among the many approaches for studying the net primary productivity (NPP), a new method by using remote sensing was introduced in this paper. With spectral information source (the visible band, near infrared band and thermal infrared band) of NOAA-AVHRR, we can get the relative index and parameters, which can be used for estimating NPP of terrestrial vegetation. By means of remote sensing, the estimation of biomass and NPP is mainly based on the models of light energy utilization. In other words, the biomass and NPP can be calculated from the relation among NPP, absorbed photosynthetical active radiation (APAR) and the rate (epsilon) of transformation of APAR to organic matter, thus: NPP = ( FPAR x PAR) x [epsilon * x sigma (T) x sigma (E) x sigma (S) x (1 - Y-m) x (1 - Y-g)]. Based upon remote sensing ( RS) and geographic information system (GIS), the NPP of terrestrial vegetation in China in every ten days was calculated, and the annual NPP was integrated. The result showed that the total NPP of terrestrial vegetation in China was 6.13 x 10(9) t C . a(-1) in 1990 and the maximum NPP was 1 812.9 g C/m(2). According to this result, the spatio-temporal distribution of NPP was analyzed. Comparing to the statistical models, the RS model, using area object other than point one, can better reflect the distribution of NPP, and match the geographic distribution of vegetation in China. 展开更多
关键词 remote sensing net primary productivity absorbed photosynthetical active radiation light energy utilization BIOMASS
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Discovery of the Longriba Fault Zone in Eastern Bayan Har Block, China and its tectonic implication 被引量:49
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作者 XU XiWei WEN XueZe +1 位作者 CHEN GuiHua YU GuiHua 《Science China Earth Sciences》 SCIE EI CAS 2008年第9期1209-1223,共15页
Re-measured GPS data have recently revealed that a broad NE trending dextral shear zone exists in the eastern Bayan Har block about 200 km northwest of the Longmenshan thrust on the eastern margin of the Qinghai-Tibet... Re-measured GPS data have recently revealed that a broad NE trending dextral shear zone exists in the eastern Bayan Har block about 200 km northwest of the Longmenshan thrust on the eastern margin of the Qinghai-Tibet Plateau. The strain rate along this shear zone may reach up to 4-6 mm/a. Our interpretation of satellite images and field observations indicate that this dextral shear zone corresponds to a newly generated NE trending Longriba fault zone that has been ignored before. The northeast segment of the Longriba fault zone consists of two subparallel N54°±5°E trending branch faults about 30 km apart, and late Quaternary offset landforms are well developed along the strands of these two branch faults. The northern branch fault, the Longriqu fault, has relatively large reverse component, while the southern branch fault, the Maoergai fault, is a pure right-lateral strike slip fault. According to vector synthesizing principle, the average right-lateral strike slip rate along the Longriba fault zone in the late Quaternary is calculated to be 5.4±2.0 mm/a, the vertical slip rate to be 0.7 mm/a, and the rate of crustal shortening to be 0.55 mm/a. The discovery of the Longriba fault zone may provide a new insight into the tectonics and dynamics of the eastern margin of the Qinghai-Tibet Plateau. Taken the Longriba fault zone as a boundary, the Bayan Har block is divided into two sub-blocks: the Ahba sub-block in the west and the Longmenshan sub-block in the east. The shortening and uplifting of the Longmenshan sub-block as a whole reflects that both the Longmenshan thrust and Longriba fault zone are subordinated to a back propagated nappe tectonic system that was formed during the southeastward motion of the Bayan Har block owing to intense resistance of the South China block. This nappe tectonic system has become a boundary tectonic type of an active block supporting crustal deformation along the eastern margin of the Qinghai-Tibet Plateau from late Cenozoic till now. The Longriba fault zone is just an active 展开更多
关键词 Qinghai-Tibet PLATEAU active BLOCK newly-generated fault zone slip rate NAPPE TECTONICS
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浅谈建筑被动式节能设计 被引量:43
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作者 陈华晋 李宝骏 董志峰 《建筑节能》 CAS 2007年第3期29-31,共3页
提出建筑节能设计的正确理念应当是以被动式设计为基础,以主动式设计为补充;
关键词 建筑节能 被动式 主动式
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肝衰竭的免疫发病机制 被引量:48
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作者 王晓晶 张小平 宁琴 《临床肝胆病杂志》 CAS 2014年第10期984-991,共8页
导致肝衰竭的主要因素包括直接损伤和免疫介导的肝损伤,越来越多的证据显示免疫介导的肝损伤在肝衰竭的发病中起到了重要作用。就免疫介导的肝损伤作一综述,囊括了人和动物的相关基础及临床研究,对天然免疫和获得性免疫,尤其是各种免疫... 导致肝衰竭的主要因素包括直接损伤和免疫介导的肝损伤,越来越多的证据显示免疫介导的肝损伤在肝衰竭的发病中起到了重要作用。就免疫介导的肝损伤作一综述,囊括了人和动物的相关基础及临床研究,对天然免疫和获得性免疫,尤其是各种免疫细胞和免疫分子的相互作用以及细胞凋亡相关分子进行了详细讨论。 展开更多
关键词 肝功能衰竭 免疫 天然 免疫 主动 细胞因子类 死亡结构域受体信号接头蛋白质类
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THEORY OF DIELECTRIC ELASTOMERS 被引量:46
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作者 Zhigang Suo (School of Engineering and Applied Sciences,Kavli Institute for Nanobio Science and Technology,Harvard University,Cambridge,MA 02138,USA) 《Acta Mechanica Solida Sinica》 SCIE EI 2010年第6期549-578,共30页
In response to a stimulus, a soft material deforms, and the deformation provides a function. We call such a material a soft active material (SAM). This review focuses on one class of soft active materials: dielectr... In response to a stimulus, a soft material deforms, and the deformation provides a function. We call such a material a soft active material (SAM). This review focuses on one class of soft active materials: dielectric elastomers. When a membrane of a dielectric elastomer is subject to a voltage through its thickness, the membrane reduces thickness and expands area, possibly straining over 100%. The dielectric elastomers are being developed as transducers for broad applications, including soft robots, adaptive optics, Braille displays, and electric generators. This paper reviews the theory of dielectric elastomers, developed within continuum mechanics and thermodynamics, and motivated by molecular pictures and empirical observations. The theory couples large deformation and electric potential, and describes nonlinear and nonequilibrium behavior, such as electromechanical instability and viscoelasticity. The theory enables the finite element method to simulate transducers of realistic configurations, predicts the efficiency of electromechanical energy conversion, and suggests alternative routes to achieve giant voltage-induced deformation. It is hoped that the theory will aid in the creation of materials and devices. 展开更多
关键词 soft active material dielectric elastomer electromechanical instability large deformation TRANSDUCER
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原发性习惯性流产的主动免疫治疗 被引量:41
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作者 林其德 赵爱民 +3 位作者 周涵春 汤希伟 严隽鸿 吴宇芬 《中华妇产科杂志》 CAS CSCD 北大核心 1996年第6期351-352,共2页
目的:探讨不同免疫次数及不同免疫原,对接受主动免疫治疗的原发性习惯性流产患者妊娠成功率的影响。方法:对38例有习惯性流产史的接受淋巴细胞主动免疫治疗的孕妇,进行回顾性分析。结果:接受2次主动免疫治疗的患者,妊娠成功率... 目的:探讨不同免疫次数及不同免疫原,对接受主动免疫治疗的原发性习惯性流产患者妊娠成功率的影响。方法:对38例有习惯性流产史的接受淋巴细胞主动免疫治疗的孕妇,进行回顾性分析。结果:接受2次主动免疫治疗的患者,妊娠成功率为87.5%(14/16),而接受4次免疫治疗的患者,成功率为86.4%(19/22),两种疗法的成功率比较,差异无显著性。采用丈夫淋巴细胞为免疫原治疗的患者,成功率为84.2%(16/19),而采用第3个体淋巴细胞为免疫原治疗的患者,成功率89.5%(17/19),两组成功率比较,差异也无显著性。结论:为预防潜在的血源感染,主动免疫疗法可从4次改为2次,而免疫原可选择患者丈夫,也可采用健康的无关第3个体。 展开更多
关键词 流产 习惯性流产 免疫疗法
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电子式互感器及其在数字化变电站中应用 被引量:42
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作者 王红星 张国庆 +1 位作者 郭志忠 蔡兴国 《电力自动化设备》 EI CSCD 北大核心 2009年第9期115-120,共6页
在描述电子式互感器的标准、定义、结构体系和分类的基础上,分析了有源和无源电子式电流与电压互感器的类型、原理、特点及其存在的主要问题,并就其在测量品质、结构体系、运行安全性、绝缘结构及成本等方面进行了比较,指出无源电子式... 在描述电子式互感器的标准、定义、结构体系和分类的基础上,分析了有源和无源电子式电流与电压互感器的类型、原理、特点及其存在的主要问题,并就其在测量品质、结构体系、运行安全性、绝缘结构及成本等方面进行了比较,指出无源电子式互感器是独立安装的互感器的理想解决方案。以IEC标准为基础,讨论了电子式互感器在数字化变电站中的逻辑位置和配置原则,分析了电子式互感器应用于数字化变电站中在提高测量精度、简化二次设备结构、增强间隔层与过程层通信、提高继电保护装置性能、完善故障录波等方面的优势。并指出在其应用中需注意可靠性和稳定性等技术问题。 展开更多
关键词 电子式互感器 光学互感器 IEC标准 数字化变电站 有源 无源
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Distribution of Soil Organic Carbon Fractions Along the Altitudinal Gradient in Changbai Mountain,China 被引量:44
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作者 ZHANG Min ZHANG Xiao-Ke +4 位作者 LIANG Wen-Ju JIANG Yong DAI Guan-Hua WANG Xu-Gao HAN Shi-Jie 《Pedosphere》 SCIE CAS CSCD 2011年第5期615-620,共6页
Understanding the responses of soil organic carbon(SOC) fractions to altitudinal gradient variation is important for understanding changes in the carbon balance of forest ecosystems.In our study the SOC and its fracti... Understanding the responses of soil organic carbon(SOC) fractions to altitudinal gradient variation is important for understanding changes in the carbon balance of forest ecosystems.In our study the SOC and its fractions of readily oxidizable carbon(ROC),water-soluble carbon(WSC) and microbial biomass carbon(MBC) in the soil organic and mineral horizons were investigated for four typical forest types,including mixed coniferous broad-leaved forest(MCB),dark coniferous spruce-fir forest(DCSF),dark coniferous spruce forest(DCS),and Ermans birch forest(EB),along an altitudinal gradient in the Changbai Mountain Nature Reserve in Northeast China.The results showed that there was no obvious altitudinal pattern in the SOC.Similar variation trends of SOC with altitude were observed between the organic and mineral horizons.Significant differences in the contents of SOC,WSC,MBC and ROC were found among the four forest types and between horizons.The contents of ROC in the mineral horizon,WSC in the organic horizon and MBC in both horizons in the MCB and EB forests were significantly greater than those in either DCSF or DCS forest.The proportion of soil WSC to SOC was the lowest among the three main fractions.The contents of WSC,MBC and ROC were significantly correlated(P < 0.05) with SOC content.It can be concluded that vegetation types and climate were crucial factors in regulating the distribution of soil organic carbon fractions in Changbai Mountain. 展开更多
关键词 active carbon fractions ALTITUDE forest ecosystem Northeast China vegetation type
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A novel advanced oxidation process to degrade organic pollutants in wastewater:Microwave-activated persulfate oxidation 被引量:41
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作者 YANG Shiying WANG Ping +3 位作者 YANG Xin WEI Guang ZHANG Wenyi SHAN Liang 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2009年第9期1175-1180,共6页
This article, for the first time, provides a novel advanced oxidation process based on sulfate radical (SO^4·-) to degrade organic pollutants in wastewater: microwave (MW)-activated persulfate oxidation (AP... This article, for the first time, provides a novel advanced oxidation process based on sulfate radical (SO^4·-) to degrade organic pollutants in wastewater: microwave (MW)-activated persulfate oxidation (APO) with or without active carbon (AC). Azo dye acid Orange 7 (AO7) is used as a model compound to investigate the high reactivity of MW-APO. It is found that AO7 (up to 1000 mg/L) is completely decolorized within 5-7 min under an 800 W MW furnace assisted-APO. In the presence of chloride ion (up to 0.50 mol/L), the decolorization is still 100% completed, though delayed for about 1-2 min. Experiments are made to examine the enhancement by AC. It is exciting to find that the 100% decolorization of AO7 (500 mg/L) is achieved within 3 min by MW-APO using 1.0 g/L AC as catalyst, while the degradation efficiency maintains at 50% by MW energy without persulfate after about 5 min. Besides the destruction of visible light chromophore band of AO7 (484 nm), during MW-APO, two bands in the ultraviolet region (228 nm and 310 nm) are rapidly broken down. The removal of COD is about 83%-95% for 500 mg/L AO7. SO^4·- is identified with quenching studies using specific alcohols. Both SO^4·- and ·OH could degrade AO7, but SO^4·- plays the dominant role. In a word, MW-APO AC is a new catalytic combustion technology for destruction of organic contamination even for high concentration. 展开更多
关键词 microwave-activated persulfate oxidation active carbon sulfate radical advanced oxidation technology
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The Large Sky Area Multi-Object Fiber Spectroscopic Telescope (LAMOST) 被引量:40
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作者 Xiang-Qun Cui Yong-Heng Zhao +52 位作者 Yao-Quan Chu Guo-Ping Li Qi Li Li-Ping Zhang Hong-Jun Su Zheng-Qiu Yao Ya-Nan Wang Xiao-Zheng Xing Xin-Nan Li Yong-Tian Zhu Gang Wang Bo-Zhong Gu A-Li Luo Xin-Qi Xu Zhen-Chao Zhang Gen-Rong Liu Hao-Tong Zhang De-Hua Yang Shu-Yun Cao Hai-Yuan Chen Jian-Jun Chen Kun-Xin Chen Ying Chen Jia-Ru Chu Lei Feng Xue-Fei Gong Yong-Hui Hou Hong-Zhuan Hu Ning-Sheng Hu Zhong-Wen Hu Lei Jia Fang-Hua Jiang Xiang Jiang Zi-Bo Jiang Ge Jin Ai-Hua Li Yan Li Ye-Ping Li Guan-QunLiu Zhi-Gang Liu Huo-Ming Shi Zheng-Hong Tang Qing-Sheng Tao Xiang-Yan Yuan Chao Zhai Jing Zhang Yan-Xia Zhang Yong Zhang Ming Zhao Fang Zhou Guo-Hua Zhou Jie Zhu Si-Cheng Zou 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2012年第9期1197-1242,共46页
The Large Sky Area Multi-Object Fiber Spectroscopic Telescope (LAMOST, also called the Guo Shou Jing Telescope) is a special reflecting Schmidt telescope. LAMOST’s special design allows both a large aperture (effecti... The Large Sky Area Multi-Object Fiber Spectroscopic Telescope (LAMOST, also called the Guo Shou Jing Telescope) is a special reflecting Schmidt telescope. LAMOST’s special design allows both a large aperture (effective aperture of 3.6 m–4.9 m) and a wide field of view (FOV) (5°). It has an innovative active reflecting Schmidt configuration which continuously changes the mirror’s surface that adjusts during the observation process and combines thin deformable mirror active optics with segmented active optics. Its primary mirror (6.67m×6.05 m) and active Schmidt mirror (5.74m×4.40 m) are both segmented, and composed of 37 and 24 hexagonal sub-mirrors respectively. By using a parallel controllable fiber positioning technique, the focal surface of 1.75 m in diameter can accommodate 4000 optical fibers. Also, LAMOST has 16 spectrographs with 32 CCD cameras. LAMOST will be the telescope with the highest rate of spectral acquisition. As a national large scientific project, the LAMOST project was formally proposed in 1996, and approved by the Chinese government in 1997. The construction started in 2001, was completed in 2008 and passed the official acceptance in June 2009. The LAMOST pilot survey was started in October 2011 and the spectroscopic survey will launch in September 2012. Up to now, LAMOST has released more than 480 000 spectra of objects. LAMOST will make an important contribution to the study of the large-scale structure of the Universe, structure and evolution of the Galaxy, and cross-identification of multiwaveband properties in celestial objects. 展开更多
关键词 techniques: wide field telescope - active optics - multi fiber - spectroscopy survey - data reduction
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