中外电气设备抗震设防标准对比分析     

尤红兵  赵凤新 《中国地震研究》2013,27(4):553-566

It is of great significance to make comparative analyses of seismic fortification criteria at home and abroad for improving the anti-seismic capability of electrical equipment and revising the relevant national standards. A brief overview of American, Japanese, IEC standards and Chinese seismic design codes for electrical equipment is presented. Differences between these seismic fortification standards of electrical equipment are compared and analyzed in respect of the goal and level of seismic fortification and the seismic design spectrum. The advantages and disadvantages of Chinese standards are pointed out. Through learning from foreign experience on the determination of seismic fortification standards, recommendations are made for the improvement and revision of Chinese seismic fortification standards for electrical equipment.  相似文献   

沂沭断裂带及附近地区分段平均波速比研究     

李霞  周彦文  赵瑞  刘瑞峰  钟普浴  王峰 《地震研究》2013,36(2)

以山东省数字地震台网产出的观测报告为基础,将沂沭断裂带及附近地区划分成4个子区域,利用多台和达法分别计算出了2002年1月至2012年4月各个子区域内中小地震平均波速比,并对其时空分布特征进行了比较.结果表明:(1)郯城—高桥段、莱州湾及附近海域平均波速比略低于孟疃—潍坊段和新沂—宿迁段,沂沭带主干断裂波速比基本分布在1.69 ～ 1.73之间,胶东半岛北部海域(120.5°E以东区域)波速比明显偏低,最低值为1.63;(2)研究区中小地震震源深度与其波速比没有明显相依关系,震源深度优势分布范围为5～20 km,反映了研究区中、上地壳介质的横向不均匀性;(3)波速比计算中,台站数目越多波速比计算误差越小,合适的空间范围的划分能更真实反映介质的变化.  相似文献   

中国海事电子海图分幅标准研究     

叶志荣  宋立伟  沙宏杰  万晓霞  焦晨晨 《测绘地理信息》2022,47(1):41-46

中华人民共和国海事局电子海图(简称中国海事电子海图)作为中国官方电子海图,经过20多年的发展,其技术体制和生产流程日趋完善,目前已通过挪威PRIMAR公司认证并公开向全世界发行.但其采用的分幅标准依旧是传统海图标准,即依据航道进行分幅,这种方法显然已不适用于电子海图.为进一步完善中国海事电子海图现有的生产模式,满足不同...  相似文献   

铬天青S光度法及非线性拟合测定高纯硅中微量铝     

傅翠梨  卢成浩  张蓉  黄平平  吴浩  罗学涛  李锦堂 《岩矿测试》2012,31(1):132-137

铬天青S光度法是硅中铝含量的测定方法之一,该方法的标准曲线大多采用不过零点的线性拟合,导致低铝含量测定误差大。为提高方法准确度并降低方法检出限,研究了铝标准曲线低浓度部分的拟合问题,探讨了不同拟合模型对检测结果准确度的影响。实验结果表明,不同浓度铝标准液的吸光度在0~0.3 μg/mL范围内并不满足一次函数线性关系,采用三次函数关系y=-17.45230x³+10.42883x²+1.04047x (y为扣空白的吸光度,x为铝的质量浓度)拟合能获得良好结果,其相关系数R²为0.99975。利用已知铝含量的硅试液检验该公式,其相对标准偏差(RSD)为2.55%。样品中铝的测定值与电感耦合等离子体发射光谱法测定值吻合。该法可以显著提高低浓度的铝测定的准确性,可用于测定高纯硅中含量在0.55 μg/g以上的铝杂质。  相似文献   

X射线荧光光谱分析在我国铁矿石分析中的应用          下载免费PDF全文

陈美芳  黄光明  江冶 《江苏地质》2012,36(2):206-211

系统介绍了20世纪90年代以来X射线荧光光谱分析（XRF）在我国铁矿石分析中的应用,包括粉末压片法和熔片法两种最基本的分析手段,主要内容集中在熔片—波长色散X射线荧光光谱分析法在我国铁矿石分析方面的测试技术,重点介绍了熔剂的类型、配比、熔片方法、熔融温度以及钴内标的使用,同时介绍了基体效应校正、谱线重叠校正等方面的内容。  相似文献   

放射性测量模型标准影响因素理论估箅和实测验证     

唐德明  王慧  何莉莉  张巍 《四川地质学报》2012,32(3):370-372

介绍了放射性各测量模型间相互干扰、建筑物对模型影响的理论估算,以确定模型与模型之间、模型与建筑物设计距离,消除各模型相互的辐射影响.通过对模型安装后的相互干扰验证,模型设计安放是合理的,达到理论估算设计要求.满足了模型标准装置检定、校准各类轻便γ闪烁辐射仪、轻便γ能谱仪、环境辐射X-γ剂量率仪要求.  相似文献   

人工合成锆石Lu-Hf同位素标样方法研究     

陈开运  袁洪林  包志安  范超  柳小明  宋佳瑶 《岩石矿物学杂志》2012,31(2):279-288

研究了人工合成锆石并加入微量元素的实验方法和条件。人工合成锆石是以氧化锆和硅酸锂为原料,以钼酸锂和氧化钼为助熔剂,并加入其他元素如Hf、Lu、Yb、U、Th、Pb等元素,充分混匀后转入带盖铂金坩埚中,在高温马弗炉中连续加热生长形成锆石晶体。利用激光剥蚀系统与电感耦合等离子体质谱技术分析了合成锆石晶体中微量元素含量和Lu-Hf同位素组成,结果表明合成锆石晶体中Lu、Yb、U、Th、Pb等微量元素含量不均一,而Hf的含量和Lu-Hf同位素组成有很好的均一性。  相似文献   

水文站水准基面关系分析   总被引：3，自引：3，他引：0  

刘琦  王峰  周珂  周宜富 《水文》2012,32(3):20-28

本文定义了基面关系式的概念,提出了基面与基本水准点考证的原则,分析了十六类基面关系式的计算方法,通过研究得出结论:基本水准点变动,冻结高程变动,基本水准点不变,冻结高程不变;绝对基面变化国冻差变化,绝对基面不变国冻差不变;冻结高程及国冻差有一项变动标准高程变动,冻结高程及国冻差都不变动标准高程不变。  相似文献   

Comparing English,Mandarin, and Russian hydrographic and terrain categories     

Chen-Chieh Feng  Alexandre Sorokine 《International journal of geographical information science》2014,28(6):1294-1315

The paper compares hydrographic and terrain categories in the geospatial data standards of the United States, Taiwan, and Russian Federation where the dominant languages used are from different language families. It aims to identify structural and semantic differences between similar categories across three geospatial data standards. By formalizing the data standard structures and identifying the properties that differentiate sibling categories in each geospatial data standard using well-known formal relations and quality universals, we develop a common basis on which hydrographic and terrain categories in the three data standards can be compared. The result suggests that all the three data standards structure categories with a mixture of relations even though most of them are well-known relations in top-level ontologies. Similar categories can be found across all the three standards. Cases of categories from different standards carrying identical meaning are rare. Partial overlaps in the meaning of the similar categories can be a direct result of different quality universals at work in defining and distinguishing these categories, or in the case of these categories being ordered by size, the threshold values for distinguishing the categories are ambiguous and language-dependent. Understanding these differences avoids incorrect mappings of categories in multilingual applications. More importantly, it provides a starting point for more effective mapping between hydrographic and terrain categories between English, Mandarin, and Russian.  相似文献   

Increased Browning of Woody Vegetation due to Continuous Seasonal Droughts in Yunnan Province,China          下载免费PDF全文

CHEN Hong-Ping  JIA Gen-Suo  FENG Jin-Ming  DONG Yan-Sheng 《大气和海洋科学快报》2014,(2):120-125

In this paper, based on the analysis of satellite measurements, the authors conclude that the continuous seasonal droughts intensify the browning of woody vegetation and that evergreen needleleaf forest（ENF） shows a larger browning percentage than other woody vegetation types over Yunnan Province. Based on the Tropical Rainfall Measuring Mission（TRMM） precipitation standardized anomaly, in the dry season, which is from October to March, the 2010 drought affected an area of Yunnan Province 1.77 times larger than the 2012 drought, but in the post-drought months（April to June）, the browning area of all woody vegetation in 2012 was 1.11 times larger than that in 2010 on the basis of the enhanced vegetation index（EVI） standardized anomaly. The reduction of vegetation greenness over large areas of Yunnan Province represents a photosynthetic capacity loss which will have an impact on carbon fluxes to the atmosphere.  相似文献