共查询到18条相似文献,搜索用时 421 毫秒
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
环境水样及食品中亚硝酸根的分析进展 总被引:5,自引:1,他引:5
评述了自1997年至2002年国内外环境水样及食品中亚硝酸根(NO2^-)的分析进展。包括分子光谱法、电化学分析法和色谱分析法,引用文献96篇。 相似文献
13.
An analytical procedure has been developed for the determination of major elements in geological material by both flame atomic-absorption spectrometry and inductively-coupled plasma atomic-emission spectrometry. Condensed phosphoric acid was used for the decomposition of 70 natural minerals containing sulphide, oxide, silicate or carbonate constituents. The results were compared with those obtained when a perchloric acid and orthophosphoric acid mixture was used for the decomposition, to ensure dissolution of even the most acid-resistant minerals. The procedure can be applied to rocks, ores, soils, slags and refractory material as a means of rapid and complete dissolution for the analysis of even the most insoluble material. 相似文献
14.
K. Simon U. Wiechert J. Hoefs B. Grote 《Analytical and bioanalytical chemistry》1997,359(4-5):458-461
Due to permanent re-equilibration processes that minerals undergo during dynamic processes within the earth, minerals build up concentration profiles – mainly from rim to core – which are ideal indicators of the geological processes the rocks have suffered. To understand these fingerprints of geological processes micro-analytical facilities are required that allow measurement of the isotopic and chemical composition of spot sizes from about 1 μm to 1 mm at concentration levels in the ng/g-range. Laser ablation techniques combined with inductively coupled plasma mass spectrometry (LA-ICPMS) and stable isotope ratio mass spectrometry (SIRMS) recently have achieved these demands. This contribution gives an example about their potential in establishing concentration gradients within minerals for geological questions. 相似文献
15.
E. B. Denechaud P. A. Helmke L. A. Haskin 《Journal of Radioanalytical and Nuclear Chemistry》1970,6(1):97-113
A procedure for analysis of 12 of the rare-earths, tested on more than a hundred samples of rocks and minerals, is described.
Carrier is added for each element to be determined. Samples are fused with Na2O2. The rare-earths are separated as a group, then precipitated and mounted as oxalates for Ge(Li) spectrometry. Following radioassay,
chemical yields for the individual rare-earths are obtained by irradiation and counting of the carrier. About two months are
needed to obtain complete data for a set of four samples, but many samples are analyzed concurrently. The precision and accuracy
exceed ±5 per cent for 10 of the elements in 0.1 to 0.5 g samples of common rocks. 相似文献
16.
R. A. Nadkarni G. H. Morrison 《Journal of Radioanalytical and Nuclear Chemistry》1977,38(1-2):435-449
A rapid and comprehensive method has been developed for the determination of ppm to sub-ppb amounts of Ru, Pd, Ag, Os, Ir,
Pt and Au, based on thermal neutron irradiation, dissolution of samples, selective absorption on Srafion NMRR ion exchange
resin and high resolution γ-ray spectrometry. Two noble metals “specific” resins were tested for their absorption behaviour.
The method has been used for analysis of standard rocks, ores, minerals, lunar samples, coal, coal fly ash, and several biological
materials. 相似文献
17.
从化学分析(破坏性分析)和非破坏性分析两个方面入手系统地介绍了岩石矿物中铀钍的分析方法。湿法化学法部分着重介绍了岩石矿物中铀钍的化学分析方法原理、特点和应用范围。常用的化学分析包括重量法、比色法、容量法、光度法、激光荧光法、极谱法、光谱法、α能谱法和先进的质谱法等;随着新仪器手段的发展进步,先进的化学分析手段特别是电感耦合等离子质谱法(ICP-MS)如雨后春笋般普及推广,其它传统湿法化学分析应用越来越少。 相似文献