ARL9400型X荧光光谱仪探测器高压部分故障分析与维修     

吴红旗 《岩矿测试》2003,22(4):307-309

简述了瑞士ARL 9400型X荧光光谱仪探测器高压部分的故障现象、分析与处理及维修方法，并给出了维修实例。  相似文献   

原子荧光光谱法测定芦荟中砷和硒   总被引：5，自引：1，他引：5       下载免费PDF全文

林章金 《岩矿测试》2003,22(3):237-238

应用AFS 820型双道原子荧光仪测定芦荟中砷和硒,方法检出限分别为As0.51μg/L;Se0.42μg/L。经国家一级植物标准物质分析验证,结果与标准值相符。5次测定相对标准偏差As<2.3%;Se<3.1%。  相似文献   

原子荧光光谱法测定化探样品时有机质对As,Sb,Bi的干扰   总被引：1，自引：0，他引：1  

汪明启  刘应汉 《地质科技情报》2003,22(1):105-109

通过研究黑龙江省森林沼泽景观区有机水系沉积物（泥炭）、土壤中As,Sb,Bi的测定结果，发现样品中的有机质对王水消解氢化物原子荧光法测定上述元素存在极大的干扰，提出采用低温（＜450℃）灰化处理可完全消除干扰。对比研究还发现，过去森林沼泽景观区的区域化探扫面资料中的As,Sb,Bi数据存在问题，应专门对其进行评价研究。  相似文献   

Enhanced red fluorescence emission in the oxygen minimum zone of the Arabian Sea     

Wiebke Breves  Rüdiger Heuermann  Rainer Reuter 《Ocean Dynamics》2003,53(2):86-97

 Depth profiles of fluorescence at several excitation and emission wavelengths were measured along with CTD data during the cruise So119 of RV Sonne in the Arabian Sea from 12 May to 10 June 1997. In addition to chlorophyll fluorescence from phytoplankton in the near-surface layer, the profiles in the oxygen minimum region well below the euphotic zone show enhanced red fluorescence. Red fluorescence intensity is inversely related to the oxygen concentration in intermediate and deep waters. A relationship to characteristic water masses of the region cannot be found in the data, and this holds also with chemical data such as DOC. Absorbance spectra of water samples taken in the oxygen minimum zone show an absorption band at 420 nm wavelength with about 50 nm bandwidth, much weaker than gelbstoff absorbance in the same wavelength range. The absorption band remains stable after sample filtration with 0.45 μm glass fibre filters. Hence, the size of the absorbing matter is in the range of dissolved molecules or particles much smaller than 1 μm. Fluorescence spectra of unfiltered samples with 420 nm excitation show a weak emission band at 600 nm and a more pronounced one at 660 nm wavelength. The trailing edge of the 660 nm band falls into the range of chlorophyll emission, thus giving rise to the observed depth profiles of red fluorescence in the oxygen minimum zone. Red fluorescence measured on samples remain stable during a few hours after sampling even in the presence of oxygen. It is not detectable after several weeks of sample storage in the dark and cannot be reproduced even after depletion of dissolved oxygen. Received: 22 May 2002 / Accepted: 18 February 2003 Responsible Editor: Andreas Oschlies Acknowledgements. This work was supported by a grant from the Federal Minister of Education and Technology, Bonn, within the frame work of the JGOFS Arabian Sea program. We are grateful to the captain and the crew of RV Sonne for their support. We are indebted to Mrs. Kirsten Neumann from the Institute of Marine Chemistry and Biogeochemistry of the University of Hamburg for providing the oxygen data, and to Mr. Nikolai Delling from the same institute for making the DOC and chlorophyll data available to us.  相似文献   

Advances in energy-dispersive X-ray fluorescence   总被引：1，自引：0，他引：1  

Utz Kramar 《Journal of Geochemical Exploration》1997,58(1):73-80

Recently, two new instruments for X-ray fluorescence analysis (XRF) with interesting features for geochemical applications came to the market. Both instruments were designed to improve the peak to background ratio, the principal factor limiting the sensitivity of XRF. Total reflection XRF (TXRF) was designed to analyse extremely small sample amounts. An instrument, using polarised X-rays (P-XRF) for excitation, is designed to reduce scattered background in spectra of bulk samples. The performance of both instruments was compared with conventional XRF-methods and ICP/MS. Results for GXR-1, GXR-2, GXR-3, GXR-4 and GXR-6 obtained with TXRF and P-XRF are in good agreement with literature data. The effective amount of sample, analysed by TXRF was 200 μg only and detection limits of ~ l μg/g were achieved. P-XRF shows considerable improved detection limits (0.25–0.5 μg/g) for bulk samples for elements with atomic numbers 42–51 (Mo-Sb) compared with conventional XRF-methods.  相似文献   

能量色散X射线荧光光谱法测定卤水中痕量溴铷砷   总被引：3，自引：4，他引：3  

樊兴涛  詹秀春  巩爱华 《岩矿测试》2004,23(1):15-18

用模拟卤水建立了能量色散X射线荧光光谱法测定卤水中溴、铷、砷痕量元素含量的方法.实验表明,方法可以直接取样测定,适用于大批量样品的测试分析.方法的精密度RSD(n＝15)小于1%,加标回收率为86.8%～101.6%.卤水中溴、铷、砷的测定结果与比色法、原子吸收和原子荧光法结果相符.  相似文献   

高倍稀释熔融制样X射线荧光光谱测定钨砂和铬铁矿中主含量   总被引：4，自引：5，他引：4  

吴秀兰  朱明达  张志峰  王伊琴 《岩矿测试》2004,23(1):73-74

用X射线荧光光谱测定钨砂中WO3和铬铁矿中Cr2O3,通过高倍稀释熔融玻璃片制样法,采用高纯WO3或Cr2O3作单一标准样测量X射线荧光强度计数,然后同未知样品测量所得X射线荧光强度计数相比,即可计算出WO3和Cr2O3的测量值.方法用于钨砂矿和铬铁矿中WO3和Cr2O3的测定,结果与标准值相符.  相似文献   

Sorption Characteristics of Rare Earth Element Eu^3＋ onto Silica-Water Interfaces Studied by Fluorescence Spectroscopy     

Yin Xiulan China Institute of Geo-environmental Monitoring  Beijing  China Hu Ping Faculty of Earth Sciences  China University of Geosciences  Wuhan  China  Northeastern Illinois University  Chicago  IL  USA Li Dien Division of Earth  Environmental Sciences  Los Alamos National Laboratory  Los Alamos  NM  USA 《中国地质大学学报(英文版)》2004,15(4):355-360

The sorption of Eu species onto nano-size silica-water interfaces was investigated using fluorescence spectroscopy for Ph ranges of 1-8.5 and an initial Eu concentration (Ceu) of 2×10-4 M. The sorption rate of Eu was initially low, but significantly increased at Ph>4. The sorption density of Eu species on a silica surface was ～1.58×10-7 mol/m2 when the dissolved Eu species were completely sorbed onto silica-water interfaces at Ph=～5.8. The sorbed Eu species at Ph<6 is aquo Eu3 , which is sorbed onto silica-water interfaces as an outer-sphere complex at Ph<5, but may be sorbed as an inner-sphere bidentate complex at 5相似文献   

Estimation of ocean primary productivity and its spatio-temporal variation mechanism for East China Sea based on VGPM model     

LI Guosheng  GAO Ping  WANG Fang  LIANG Qiang 《地理学报》2004,14(1):32-40

According to calculation results of ocean chlorophyll concentration based on SeaWiFS data by SeaBAM model and synchronous ship-measured data, this research set up an improved model for CaseⅠand CaseⅡwater bodies respectively. The monthly chlorophyll distribution in the East China Sea in 1998 was obtained from this improved model on calculation results of SeaBAM. The euphotic depth distribution in 1998 in the East China Sea is calculated by using remote sensing data of K490 from SeaWiFS according to the relation between the euphotic depth and the oceanic diffuse attenuation coefficient. With data of ocean chlorophyll concentration, euphotic depth, ocean surface photosynthetic available radiation (PAR), daily photoperiod and optimal rate of daily carbon fixation within a water column, the monthly and annual primary productivity spatio-temporal distributions in the East China Sea in 1998 were obtained based on VGPM model. Based on analysis of those distributions, the conclusion can be drawn that there is a clear bimodality character of primary productivity in the monthly distribution in the East China Sea. In detail, the monthly distribution of primary productivity stays the lowest level in winter and rises rapidly to the peak in spring. It gets down a little in summer, and gets up a little in autumn. The daily average of primary productivity in the whole East China Sea is 560.03 mg/m2/d, which is far higher than the average of subtropical ocean areas. The annual average of primary productivity is 236.95 g/m2/a. The research on the seasonal variety mechanism of primary productivity shows that several factors that affect the spatio-temporal distribution may include the chlorophyll concentration distribution, temperature condition, the Yangtze River diluted water variety, the euphotic depth, ocean current variety, etc. But the main influencing factors may be different in each local sea area.  相似文献   

Sorption of Eu~(3+) onto nano-size silica-water interfaces     

HU Ping    YIN Xiulan  ZHAO Linghu & LI Dien . Department of Earth Sciences  China University of Geosciences  Wuhan  China  . Northeastern Illinois University  Chicago  IL  USA  . China Institute of Geo-Environmental Monitoring  Beijing  China  . Division of Chemistry  Los Alamos National Laboratory  Los Alamos  NM  USA 《中国科学D辑(英文版)》2005,48(11)

A large amount of nuclear wastes has been pro-duced due to nuclear weapon development and nuclear electricity generation. One possible resolution for the disposal of the nuclear wastes is to seal them in an underground repository, which requires detailed knowledge on the mobility, chemical behavior and immobilization of radionuclides in underground water. In addition, toxic heavy metals are extensively present in ground and underground water, how to immobilize and remedy these toxic heavy meta…  相似文献