Determination of trace and rare-earth elements in Chinese soil and clay reference materials by ICP-MS   总被引：2，自引：0，他引：2  

Ye Liu  Chunrong Diwu  Yan Zhao  Xiaoming Liu  Honglin Yuan  Jianqi Wang 《中国地球化学学报》2014,33(1):95-102

Inductively coupled plasma mass spectrometry(ICP-MS) has become a powerful tool for providing reliable analytical results in many laboratories around the word. In this study, the mixture of HF and HNO3 acids in high-temperature and high-pressure closed-vessel digestion technique were used to decompose some Chinese reference materials, and thirty seven elements were determined by ICP-MS. Most of the results for Chinese soil reference materials were found to be in reasonable agreement with the reference values, except Cs, Ta, Li, Ge, Zn, Nd, Tb and Ta whose values need to be revised. Their precisions were typically lower than 5% RSD. However, the Precisions of Chinese clay reference materials, especially for GBW03102 and GBW03102a, were significantly different with reference values, probably reflecting the existence of a coarser-grained fraction(70 μm) in samples, and the formation of fluorides in Al-rich samples during sample decomposition by using the mixture of HF and HNO3 acids. Moreover, thirty-seven trace elements covering the mass range from Li to U in four Chinese clay reference materials were firstly provided with good precision and accuracy in this study.  相似文献   

利用GNSS星间链路对中高轨航天器测定轨的可行性研究     

孟轶男  樊士伟  李罡  高为广 《武汉大学学报(信息科学版)》2014,(4)

目前中高轨航天器精密轨道确定普遍采用地面跟踪测量体制,面临跟踪弧段不够、跟踪精度不高、无载体自主定位能力的问题。GNSS星间链路网络的建立为中高轨航天器定轨提供了新思路。介绍了基于GNSS星间链路的中高轨航天器定轨新方法,设计仿真模型分析了其可见性、定位精度、链路预算,并进行了自主定轨模拟计算。结果表明:以GNSS星间链路实现中高轨航天器测定轨,可见星数目多、定位精度好、链路余量高,对中高轨航天器在径向的定轨精度可以达到6m以内,切向和法向在2m以内。本文测定轨方案可行,为GNSS在新领域的应用提供了思路。  相似文献   

基于遥感技术的重庆市CO_2浓度空间分布估算     

陈雪洋  金贤锋  瞿晓雯 《地理空间信息》2014,(6):103-106

借助遥感影像和实地CO2浓度测试数据,提出一种基于遥感技术的CO2浓度测定方法,并以重庆市为对象开展了实证,对CO2排放主因与问题进行了分析,提出了低碳发展的对策,对重庆市低碳城市试点的开展具有指导意义。  相似文献   

全站仪精确测定CORS基准站天线高的方法研究     

王俊民  任秀波  程小凯  雷鹏  李拥军  陈永生 《测绘技术装备》2014,(2):94-96

首先对全站仪精确测定CORS基准站天线高的基本原理进行了阐述,然后详细介绍了该方法的实施步骤,包括仪器选取、技术指标、观测步骤以及计算等流程,并与二等水准观测成果进行了对比。  相似文献   

ENVIRONMENTAL CHANGE AND ITS IMPACTS ON HUMAN SETTLF, MENT IN THE CHANGJIANG RIVER DELTA IN NEOLITHIC AGE   总被引：1，自引：0，他引：1  

ZHANGQiang LIUChun-ling ZHUCheng JIANGTong 《中国地理科学(英文版)》2004,14(3):239-244

Dating data, altitude of Neolithic sites, climatic changes from sedimentary records and previous research results were collected and analyzed to detect possible connections between climatic changes and human activities in the Changjiang River Delta in the Neolithic Age. The results indicated that hydrological changes greatly impacted the human activities in the study region. Low-lying geomorphology made the floods and sea level changes become the important factors affecting human activities, especially the altitude change of human settlements. People usually moved to higher places during the periods characterized by high sea level and frequent floods to escape the negative influences from water body expansion, which resulted in cultural hiatus in certain profiles. However, some higher-altitude settlements were not the results of climatic changes but the results of social factors, such as religious ceremony and social status. Therefore, further research will be necessary for the degree and types of impacts of climatic changes on human activities in the study area at that time.  相似文献   

关于建立与地球的动力学平面无关的天球参考架     

赵铭 《天文学报》1991,32(3):297-303

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示波极谱法连测预混合饲料中的铅和镉     

李吉生 《青海国土经略》2005,(3):44-45

研究了示波吸附催化极谱法测定预混合饲料中铅和镉及样品的前期处理和条件试验。结果表明方法的精密度RSD≤7.9%,方法检出限Pb 0.04ug.ml^-1，Cd 0.005ug.ml^-1，标准回收率为93%-106%，其方法具有良好的应用效果。  相似文献   

测定人生的坐标——记共产党员、获嘉县国土资源局测绘队队长温全州     

孔令东  郭亮 《河南国土资源》2005,(8):30-31

2005年4月14日，对大多数人而言或许是一个极普通的日子。但对于获嘉县国土资源局测绘队队长温全州来说，却是一个值得欣慰和自豪的日子。获嘉县国土资源局举行的温全州同志先进事迹报告会，赢得了一阵又一阵热烈的掌声。  相似文献   

煤中汞的测定     

陈菊英 《岩矿测试》1991,10(3):240-240237

煤中Hg是一种有害元素,以无机化合物和有机Hg的形式存在于煤中。一般含量很低,可以采用冷原子吸收法测定。但由于煤中Hg及其化合物在分解过程中易挥发,试样的分解成了方法的关键。本文选择HNO_3-H_2SO_4分解煤样并加助溶剂V_2O_5,可以分解煤样中的碳及其有机化合物,使Hg定量转入待测溶液中,最后用冷原子吸收法完成Hg的测定。方法简单快速,灵敏度高,重现性好。实验部分一、仪器及主要试剂仪器:CH7601汞分析仪。V_2O_5经500℃灼烧30min后备用。  相似文献   

低纬子午环绝对测定仪器瞬时方位差方法的改进（Ⅱ）   总被引：1，自引：1，他引：0  

彭青玉 《云南天文台台刊》1997,(1):56-59

在导出低纬子午环测定一颗星过卯酉、子午圈的记录时刻与瞬时方位差关系式的基础上，结合仪器在卯酉圈测定星对天顶距的方法，提出了既可以绝对测定瞬时方位差，又可以绝对测定定误差ε的新设想。  相似文献