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Use of Research Reactors for Neutron Activation Analysis IAEA-TECDOC-1215 Use of research reactors for neutron activation analysis Report of an Advisory Group meeting held in Vienna, 22–26 June 1998 April 2001 The originating Section of this publication in the IAEA was: Physics Section International Atomic Energy Agency Wagramer Strasse 5 P.O. Box 100 A-1400 Vienna, Austria USE OF RESEARCH REACTORS FOR NEUTRON ACTIVATION ANALYSIS IAEA, VIENNA, 2001 IAEA-TECDOC-1215 ISSN 1011–4289 © IAEA, 2001 Printed by the IAEA in Austria April 2001 FOREWORD Neutron activation analysis (NAA) is an analytical technique based on the measurement of characteristic radiation from radionuclides formed directly or indirectly by neutron irradiation of the material of interest. In the last three decades, neutron activation analysis has been found to be extremely useful in the determination of trace and minor elements in many disciplines. These include environmental analysis applications, nutritional and health related studies, geological as well as material sciences. The most suitable source of neutrons for NAA is a research reactor. There are several application fields in which NAA has a superior position compared to other analytical methods, and there are good prospects in developing countries for long term growth. Therefore, the IAEA is making concerted efforts to promote neutron activation analysis and at the same time to assist developing Member States in better utilization of their research reactors. As part of this activity, the IAEA organized an Advisory Group Meeting on “Enhancement of Research Reactor Utilization for Neutron Activation Analysis” in Vienna from 22 to 26 June 1998. The purpose of the meeting was to discuss the benefits and the role of NAA in applications and research areas that may contribute towards improving utilization of research reactors. The participants focused on five specific topics: (1) Current trends in NAA; (2) The role of NAA compared to other methods of chemical analysis; (3) How to increase the number of NAA users through interaction with industries, research institutes, universities and medical institutions; (4) How to reduce costs and to maintain quality and reliability; (5) NAA using low power research reactors. This TECDOC details the highlights of the discussions in the meeting along with the papers presented. The IAEA is grateful to Mr. P. Bode (Delft University of Technology, Netherlands) for compiling the publication. It is hoped that it will enhance the effectiveness of research reactor laboratories and help identify fields of application where neutron activation analysis can be of value. The IAEA officer responsible for this publication was B. Dodd of the Division of Physical and Chemical Sciences. EDITORIAL NOTE This publication has been prepared from the original material as submitted by the authors. The views expressed do not necessarily reflect those of the IAEA, the governments of the nominating Member States or the nominating organizations. The use of particular designations of countries or territories does not imply any judgement by the publisher, the IAEA, as to the legal status of such countries or territories, of their authorities and institutions or of the delimitation of their boundaries. The mention of names of specific companies or products (whether or not indicated as registered) does not imply any intention to infringe proprietary rights, nor should it be construed as an endorsement or recommendation on the part of the IAEA. The authors are responsible for having obtained the necessary permission for the IAEA to reproduce, translate or use material from sources already protected by copyrights. CONTENTS 1. INTRODUCTION...................................................................................................................1 2. CURRENT TRENDS IN NEUTRON ACTIVATION ANALYSIS ......................................2 2.1. Trends 2 2.2. Typical applications ........................................................................................................3 3. THE ROLE AND OPPORTUNITIES OF NAA COMPARED TO OTHER METHODS OF CHEMICAL ANALYSIS..............................................................5 3.1. Developments with other methods for elemental anaysis ...............................................5 3.2. Characteristics of INAA compared to other methods of elemental analysis............................................................................................................................5 3.3. Evaluation, and opportunities for INAA .........................................................................6 3.4. Additional niches.............................................................................................................7 4. HOW TO INCREASE THE NUMBER OF NAA USERS ....................................................8 4.1. Introduction .....................................................................................................................8 4.2. Credibility........................................................................................................................9 4.3. Leadership .......................................................................................................................9 4.4. Markets to target............................................................................................................10 4.5. Presentation ...................................................................................................................11 4.6. Management ..................................................................................................................12 4.7. Networking....................................................................................................................12 4.8. Publicity ........................................................................................................................13 5. HOW TO REDUCE COSTS AND TO MAINTAIN QUALITY AND RELIABILITY OF NAA......................................................................................................13 6. CASE STUDY OF AN NAA SERVICE LABORATORY..................................................15 7. USE OF NAA IN INDUSTRY.............................................................................................17 8. NAA USING LOW POWER REACTORS..........................................................................18 9. CONCLUSIONS...................................................................................................................19 REFERENCES .........................................................................................................................21 ANNEX I: METHODOLOGY OF NEUTRON ACTIVATION ANALYSIS .........................23 ANNEX II: PAPERS PRESENTED AT THE ADVISORY GROUP MEETING Is activation analysis still active?..............................................................................................31 Zhifang Chai Molecular activation analysis for chemical species studies......................................................35 Zhifang Chai, Xueying Mao, Yuqi Wang, Jingxin Sun, Qingfang Qian, Xiaolin Hou, Peiqun Zhang, Chunying Chen, Weiyu Feng, Wenjun Ding, Xiaolin Li, Chunsheng Li, Xiongxin Dai Selected environmental applications of neutron activation analysis.........................................43 J. Kučera Enhancement of research reactor utilization for neutron activation analysis............................57 R. Parthasarathy Utilization of the SLOWPOKE-2 research reactor...................................................................71 G.C. Lalor From scientific research towards scientific service by INAA: Experiences and consequences........................................................................................................................75 P. Bode A strategy for the survival and enrichment of NAA in a wider context ...................................83 A.R. Byrne Industrial applications of neutron activation analysis...............................................................93 T.Z. Hossain List of Participants ....................................................................................................................97 1. INTRODUCTION Over the past fifty years, research reactors have progressed through a variety of tasks. These have included materials research using neutron scattering and diffraction, materials characterization by activation analysis and radiography, isotope production, irradiation testing, as well as training, and service as centres of excellence in science and technology. There have been a number of IAEA sponsored meetings, seminars and symposia on research reactor utilization. In spite of these efforts, research reactors in some countries are still under-utilized. This is especially true in the 39 developing countries which together have 84 operational research reactors [1]. Since research reactors have a high capital cost and require a substantial operating budget, the IAEA makes efforts to assist in their effective utilization. As part of that project, the IAEA organized an Advisory Group Meeting on “Enhancement of Research Reactor Utilization for Neutron Activation Analysis” which was held in Vienna, 22–26 June 1998. Neutron activation analysis (NAA) is a method for qualitative and quantitative determination of elements based on the measurement of characteristic radiation from radionuclides formed directly or indirectly by neutron irradiation of the material. The most suitable source of neutrons is usually a nuclear research reactor. The method’s
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