Download or read book CALORIMETER BASED ADJUSTMENT OF MULTIPLICITY DETERMINED 240PU EFF KNOWN A ANALYSIS FOR THE ASSAY OF PLUTONIUM written by and published by . This book was released on 2012 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: In nuclear material processing facilities, it is often necessary to balance the competing demands of accuracy and throughput. While passive neutron multiplicity counting is the preferred method for relatively fast assays of plutonium, the presence of low-Z impurities (fluorine, beryllium, etc.) rapidly erodes the assay precision of passive neutron counting techniques, frequently resulting in unacceptably large total measurement uncertainties. Conversely, while calorimeters are immune to these impurity effects, the long count times required for high accuracy can be a hindrance to efficiency. The higher uncertainties in passive neutron measurements of impure material are driven by the resulting large (”2)?-values, defined as the (?, n):spontaneous fission neutron emission ratio. To counter impurity impacts for high-? materials, a known-? approach may be adopted. In this method,? is determined for a single item using a combination of gamma-ray and calorimetric measurements. Because calorimetry is based on heat output, rather than a statistical distribution of emitted neutrons, an?-value determined in this way is far more accurate than one determined from passive neutron counts. This fixed? value can be used in conventional multiplicity analysis for any plutonium-bearing item having the same chemical composition and isotopic distribution as the original. With the results of single calorimeter/passive neutron/gamma-ray measurement, these subsequent items can then be assayed with high precision and accuracy in a relatively short time, despite the presence of impurities. A calorimeter-based known-? multiplicity analysis technique is especially useful when requiring rapid, high accuracy, high precision measurements of multiple plutonium bearing items having a common source. The technique has therefore found numerous applications at the Savannah River Site. In each case, a plutonium (or mixed U/Pu) bearing item is divided into multiple containers. A single item from that batch is then selected for both neutron and calorimetric measurements; all remaining items undergo a neutron measurement only. Using the technique mentioned above, the 'true'? value determined from the first (calorimeter and passive neutron measured) item is used in multiplicity analysis for all other items in the batch. The justification for using this? value in subsequent calculations is the assumption that the chemical composition and isotopic distribution of all batch items are the same, giving a constant (?, n):spontaneous fission ratio. This analysis method has been successfully applied to the KIS Facility, significantly improving measurement uncertainties and reducing processing times for numerous items. Comprehensive plans were later developed to extend the use of this method to other applications, including the K-Area Shuffler and the H-Area Pu-Blending Project. While only the feasibility study for the Shuffler has been completed, implementation of the method in the H-Area Pu-Blending Project is currently in progress and has been successfully applied to multiple items. This report serves to document the details of this method in order to serve as a reference for future applications. Also contained herein are specific examples of the application of known-? multiplicity analysis.
Download or read book A Calorimetric Determination of the Energy Produced by Plutonium 239 written by J. W. Stout and published by . This book was released on 1946 with total page 24 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Importance of 241 Am Determination in the Characterization of PuO2 Standards for Calorimetric Assay written by and published by . This book was released on 2005 with total page 11 pages. Available in PDF, EPUB and Kindle. Book excerpt: Plutonium dioxide (PuO2) standards are often used both as heat standards and isotopic standards for calorimetric assay. Calorimetric assay is the combination of the power in watts measured in a calorimeter with the effective specific power (P{sub eff}) in watts/g Pu, determined either by nondestructive gamma-ray assay or by destructive mass spectrometry, to yield the total elemental plutonium mass in the sample. To use a PuO2 sample as a heat standard for calorimetry, one must determine both the plutonium mass and P{sub eff} with very small uncertainties and then calculate the sample watts from the known plutonium mass, specific powers, and isotopic composition. Well-characterized PuO2 standards have plutonium mass values determined by analytical chemistry with a precision and accuracy on the order of 0.1%-0.2% relative to the total mass of the sample. Mass spectrometry, typically used to determine the isotopic fractions of plutonium standards, is very accurate and precise for the major isotopes but is somewhat less precise for low-abundance isotopes. The characterization of the 241Am/Pu ratio in the standard is also of great importance because 241Am can contribute significantly to P{sub eff} and to the heat output of the standard. The determination of the 241Am/Pu ratio in a plutonium-bearing sample is a process that is less standardized than mass spectrometry. There are no certified reference materials (CRMs) traceable to the national measurement system for 241Am in plutonium, and routine analytical 241Am/Pu ratio measurements often exhibit uncertainties of several percent relative to the total plutonium or greater.
Download or read book Acid Dissolution Method for the Analysis of Plutonium in Soil written by E. L. Whittaker and published by . This book was released on 1979 with total page 72 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Calibration of Plutonium NDA by Calorimetric Assay written by and published by . This book was released on 1978 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The calorimetric assay of plutonium is an established and documented technique used extensively in DOE facilities for accountability measurements. Multilaboratory studies have quantified an average bias of
Download or read book An Evaluation of the Use of Calorimetry for Shipper receiver Measurements of Plutonium written by W. W. Rodenburg and published by . This book was released on 1978 with total page 90 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Standard Test Method for Nondestructive Assay of Plutonium by Passive Neutron Multiplicity Counting written by and published by . This book was released on with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Annual Book of ASTM Standards written by ASTM International and published by . This book was released on 2004 with total page 1252 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Passive Nondestructive Assay of Nuclear Materials written by Doug Reilly and published by . This book was released on 1991 with total page 700 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Strategy and Methodology for Radioactive Waste Characterization written by International Atomic Energy Agency and published by IAEA. This book was released on 2007 with total page 188 pages. Available in PDF, EPUB and Kindle. Book excerpt: Over the past decade significant progress has been achieved in the development of waste characterization and control procedures and equipment as a direct response to ever-increasing requirements for quality and reliability of information on waste characteristics. Failure in control procedures at any step can have important, adverse consequences and may result in producing waste packages which are not compliant with the waste acceptance criteria for disposal, thereby adversely impacting the repository. The information and guidance included in this publication corresponds to recent achievements and reflects the optimum approaches, thereby reducing the potential for error and enhancing the quality of the end product. -- Publisher's description.
Download or read book Transactions of the American Nuclear Society written by and published by . This book was released on 1958 with total page 608 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Safeguards Techniques and Equipment written by International Atomic Energy Agency and published by . This book was released on 2011 with total page 146 pages. Available in PDF, EPUB and Kindle. Book excerpt: The 1990s saw significant developments in the global non-proliferation landscape, resulting in a new period of safeguards development. The current publication, which is the second revision and update of IAEA/NVS/1, is intended to give a full and balanced description of the safeguards techniques and equipment used for nuclear material accountancy, containment and surveillance measures, environmental sampling, and data security. New features include a section on new and novel technologies. As new verification measures continue to be developed, the material in this book will be reviewed periodically and updated versions issued.
Download or read book Handbook of Nuclear Chemistry written by Attila Vértes and published by Springer Science & Business Media. This book was released on 2010-12-10 with total page 3693 pages. Available in PDF, EPUB and Kindle. Book excerpt: This revised and extended 6 volume handbook set is the most comprehensive and voluminous reference work of its kind in the field of nuclear chemistry. The Handbook set covers all of the chemical aspects of nuclear science starting from the physical basics and including such diverse areas as the chemistry of transactinides and exotic atoms as well as radioactive waste management and radiopharmaceutical chemistry relevant to nuclear medicine. The nuclear methods of the investigation of chemical structure also receive ample space and attention. The international team of authors consists of scores of world-renowned experts - nuclear chemists, radiopharmaceutical chemists and physicists - from Europe, USA, and Asia. The Handbook set is an invaluable reference for nuclear scientists, biologists, chemists, physicists, physicians practicing nuclear medicine, graduate students and teachers - virtually all who are involved in the chemical and radiopharmaceutical aspects of nuclear science. The Handbook set also provides further reading via the rich selection of references.
Download or read book Physics and Astrophysics of Neutrinos written by Masataka Fukugita and published by Springer Science & Business Media. This book was released on 2013-12-14 with total page 947 pages. Available in PDF, EPUB and Kindle. Book excerpt: Observations of neutrinos being emitted by the supernova SN1987A, star neutrinos, and atmospheric neutrinos have provided new insights into astronomy, as well as new unresolved phenomena such as the solar neutrino problem, spurring investigative studies among particle physicists and astrophysicists. One of the most important features of this book is its enumeration of a number of basic properties of neutrinos and their relationship to Grand Unified Theories, focusing on the origin of the neutrino's mass and the generation mixing of neutrinos. All the kamiokande results, detector performances, and complete references are included.
Download or read book 14 MeV Neutrons written by Vladivoj Valkovic and published by CRC Press. This book was released on 2015-08-25 with total page 500 pages. Available in PDF, EPUB and Kindle. Book excerpt: Despite the often difficult and time-consuming effort of performing experiments with fast (14 MeV) neutrons, these neutrons can offer special insight into nucleus and other materials because of the absence of charge. 14 MeV Neutrons: Physics and Applications explores fast neutrons in basic science and applications to problems in medicine, the envir
Download or read book Photoneutron Sources written by B. W. Sargent and published by . This book was released on 1946 with total page 8 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Pathways to Modern Chemical Physics written by Salvatore Califano and published by Springer Science & Business Media. This book was released on 2012-05-26 with total page 293 pages. Available in PDF, EPUB and Kindle. Book excerpt: In this historical volume Salvatore Califano traces the developments of ideas and theories in physical and theoretical chemistry throughout the 20th century. This seldom-told narrative provides details of topics from thermodynamics to atomic structure, radioactivity and quantum chemistry. Califano’s expertise as a physical chemist allows him to judge the historical developments from the point of view of modern chemistry. This detailed and unique historical narrative is fascinating for chemists working in the fields of physical chemistry and is also a useful resource for science historians who will enjoy access to material not previously dealt with in a coherent way.
