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991.
月球测绘在月球探测中的应用 总被引:7,自引:1,他引:7
根据探月历史概述了月球测绘与月球探测的关系、月球探测的焦点和我国探月计划;分析研究了月球测绘的关键技术;论述了月球测绘在月球探测中的应用。 相似文献
992.
连云港市地籍测量坐标系统的选择 总被引:1,自引:0,他引:1
通过对连云港市测量坐标系统的现状分析,提出了建立适宜于连云港市地籍测量的新的坐标系统 的具体方法,为本市地籍测量工作服务。 相似文献
993.
电子全站仪(或光电测距仪)测距部参数的获知方法 总被引:2,自引:0,他引:2
提出了根据电子全站仪(或光电测距仪)用户手册中的气象改正(或乘常数改正,即ppm值)公式获得测距部大气参考状态、激光器载波波长的方法,从而使精密测距的测距值人工气象改正变为可能。 相似文献
994.
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996.
Neutron Activation Analysis, Atomic Absorption and X-Ray Fluorescence Spectrometry Review for 2003 总被引:1,自引:0,他引:1
This review for the year 2003 deals with three relatively well-established, mature, analytical techniques (neutron activation analysis, atomic absorption spectrometry and X-ray fluorescence spectrometry) that nevertheless remain very important for the characterisation of geological and environmental samples. Developments in neutron activation analysis included modification to the technique in relation to the determination of platinum-group elements, as well as consideration of sample size in ore grade estimation. A considerable body of literature was published on the application of atomic absorption spectrometry in the analysis of environmental samples. Many of these proposed technical and methodological improvements, notably in extraction procedures. X-ray fluorescence spectrometry saw developments in in situ analysis, synchrotron micro-XRF (μ-SRXRF) and a confocal X-ray set-up for 3D elemental imaging. XRF technologies were used in the analysis of geological samples, reference materials, glasses, solutes and environmental materials. 相似文献
997.
Lance P. Black 《Geostandards and Geoanalytical Research》2005,29(2):169-182
Data from a series of extended analytical sessions using a range of different zircon reference samples have been used to investigate the periodic derivation of abnormal 207 Pb/206 Pb ages during microbeam analysis%For the Canberra SHRIMP II, this phenomenon probably results from the presence of a signal at mass 204 that is alien to the Pb spectrum; isotopic fractionation is unlikely to be a significant contributor. In contrast, abnormal 207 Pb/206 Pb ages obtained from SHRIMP I at the same research centre require a different, but as yet unknown explanation. Assessment of the reasons for atypical 207Pb /206 Pb measurements and the means of correcting for them should therefore be independently assessed for individual analytical instruments. The use of reference samples with very different ages is an effective way of doing this, because older reference samples are more useful for documenting isotopic fractionation, whereas younger ones are more sensitive indicators of isobaric interference. 相似文献
998.
Chunhan Tong Sichun Zhou Juchu Li Xiaohui Liu Jianping Wu 《Geostandards and Geoanalytical Research》2005,29(2):225-231
A basaltic certified reference material BEM, prepared by Chengdu University of Technology, has recently been approved as a Primary Grade Reference Material (GBW07126) by the General Administration of Quality Supervision, Inspection and Quarantine of China. BEM was sampled from the Emeishan Basalts in China, which is one of the largest basalt provinces in the world. After successfully completing homogeneity and stability tests, collaborative analyses were carried out in seventeen Chinese institutes and laboratories and two American laboratories. More than ten reliable analytical methods based on different principles of measurement were adopted, of which ICP-MS, NAA and ICP-AES contributed 60.5% of all results. Fifty-four elements and oxide components were characterised as certified values, four elements as recommended values and nine elements as information values. A minimum sampling mass of 40 mg for most elements is recommended for use. 相似文献
999.
Klaus Peter Jochum Uwe Nohl Kirstin Herwig Esin Lammel Brigitte Stoll Albrecht W. Hofmann 《Geostandards and Geoanalytical Research》2005,29(3):333-338
We have developed a new database named GeoReM ( http://georem.mpch-mainz.gwdg.de ) for reference materials and isotopic standards of geochemical and mineralogical interest. Reference samples include rock powders originating from the USGS, GSJ, GIT-IWG, synthetic and natural reference glasses originating from NIST, USGS, MPI-DING, as well as mineral (e.g., 91500 zircon), isotopic (e.g., La Jolla, E&A, NIST SRM 981), river water and seawater reference materials. GeoReM is a relational database, which strongly follows the concept of the three EARTHCHEM databases. It contains published analytical and compilation values (major and trace element concentrations, radiogenic and stable isotope ratios), important metadata about the analytical values, such as uncertainty, uncertainty type, method and laboratory. Sample information and references are also included. Three different ways of interrogating the database are possible: (1) sample names or material types, (2) chemical criteria and (3) bibliography. Some typical applications are described. GeoReM currently (October 2005) contains more than 750 geological reference materials, 6000 individual sets of results and references to 650 publications. 相似文献
1000.
Paleomagnetic characteristics of several Paleogene sections in Kamchatka (Il’pinskii Peninsula, Bering Island, Chemurnaut Bay, Mametcha Bay) are considered. The sections are correlated with due account for biostratigraphic data, and possible correlation of magnetic polarity zones distinguished in the sections with the international magnetostratigraphic scale is presented. 相似文献