Inductively coupled plasma-mass spectrometry (ICP-MS) was used to concurrently determine multiple long-lived (t_ > 104 y) actinide isotopes in soil samples. Ultrasonic nebulization was found to maximize instrument sensitivity. Instrument detection limits for actinides in solution ranged from 50 mBq L-I (ngPu) to 2 _Bq L-I (23SU). Hydride adducts of n2Th and 238U interfered with the determinations of 233U and 239pu; thus, extraction chromatography was used to eliminate the sample matrix, concentrate the analytes, and separate uranium from the other actinides. Alpha spectrometric determinations of 23°Th, ngPu, and the 234U/nsU activity ratio in soil leachates compared well with ICP-MS determinations; however, there were some small systematic differences (ca. 10%) between ICP-MS and _-spectrometric determinations of 234U and 238U activities.
Recently there has been much concern with the ability of plants to uptake heavy metals from their surroundings. With the development of instrumental techniques with low detection limits such as inductively coupled plasma-mass spectrometry (ICP-MS), attention is shifting toward achieving faster and more elegant ways of oxidizing the organic material inherent in environmental samples. Closed-vessel microwave dissolution was compared with conventional methods for the determination of concentrations of cerium, samatium, europium, t sr b' ium, uranium and thorium in a series of samples from the National Institute of Standards and Technology and from fields in Idaho. The ICP-MS technique exhibited detection limits in partsper-trillion and linear calibration plots over three orders of magnitude for the elements under study. The results obtained by using nitric acid and hydrogen peroxide in a microwave digestion system for the analysis of reference materials showed close agreement with the accepted values.These values were compared with results obtained from dry-and wet-ashing procedures. The findings from an experiment comparing radiometric techniques for the determination of actinide elements to ICP-MS are reported. DISCLAIMERThis report was prepared as an account of work sponsored by an agency of the United States Government. Neither the United States Government nor any agency thereof, nor my of their employees, makes any warranty, express or implied, or assumes any legal liability or responsibility for the accuracy, completeness, or usefulness of any information, apparatus, product, or process disclosed, or represents that its use would not infringe privately owned rights. Reference herein to any specific commercial product, process, or service by trade name, trademark, manufacturer, or otherwise does not necessarily constitute or imply its endorsement, recommendation, or favoring by the United States Government or any agency thereof. The views and opinions of authors expressed herein do not necessarily state or reflect those of the United States Government or any agency thereof. INTR0DC:CTIONAs a result of ongoing industrial pollution and the vital role of plants in the food chain, interest has increased in the ability of plants to uptake potentially hazardous heavy metals from their surroundings. Much attention has also been given to the field of radiological safety, including the determination of small amounts of actinide elements in botanical tissues, as a component of individual contamination-monitoring problems (1). Because environmental samples have large amounts of organic matrix elements but may have low concentrations of the rare earth elements, a digestion procedure whereby the organic matrix is oxidized, leaching the metals from the matrix, must be coupled with an instrumental technique with characteristically low limits of detection.Problems typically arising from the determination of elements in environmental samples are not associated with the efficiency of the instrumental method, but rather ...
We have developed methods for chemical characterization of the environment under a multitask project that focuses on improvement of radioanalytical methods with an emphasis on faster and cheaper routine methods. We have developed improved methods for separation of environmental levels of technetium-99, radium, and actinides from soil and water; separation of actinides from soil and water matrix interferences; and isolation of strontium. Wc are also developing methods for simultaneous detection of multiple isotopes (including nonradionuclides) by using a new instrumental technique, inductively coupled plasma-mass spectrometry (ICP-MS).The new ICP-MS methods have greater sensitivity and efficiency and could replace many radiometric techniques. We are using flow injection analysis to integrate and automate the separation methods with the ICP-MS methodology. The objective of automating methods is to achieve more reproducible results, reduce labor costs, cut analysis time, and minimize secondary waste generation through miniaturization of the process. The final product of all activities will be methods that are available (published in the U.S. Department of Energy's analytical methods compendium) and acceptable for use in regulatory situations.Our nation faces a daunting challenge to clean up and protect our environment; before launching any cleanup, one must characterize the type, concentration, and extent of the contamination. During cleanup one must monitor the progress, and after cleanup, one must often monitor the site to ensure that the cleanup was successful. Chemical characterization and monitoring techniques and methods are essential in the execution of these efforts. R&D efforts to improve capabilities can translate into major savings and improvement in environmental cleanup by reducing the unit cost of measurements (e.g., fewer steps in an analysis), reducing the time required to provide the information to the user (e.g., field analysis), or improving the information quality (e.g., chemical speciation). Radiochemical analysis is of particular concern to the U.S. Department of Energy, which expends over $300 million annually on this activity. Unlike organic and inorganic analytes, which are widely found as contaminants, comparatively little effort has been expended on improvements of radiochemical analyses. Desirable characteristics of any new methods for characterization of the Department's radiochemical contamination are the foLlowing: r,°,°b_,,._ _.nu_._, .., _.o..,,o_0_
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.