Download or read book A Comprehensive Study of the Neutron Activation Analysis of Uranium by Delayed neutron Counting written by F. F. Dyer and published by . This book was released on 1962 with total page 82 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book A COMPREHENSIVE STUDY OF THE NEUTRON ACTIVATION ANALYSIS OF URANIUM BY DELAYED NEUTRON COUNTING written by and published by . This book was released on 1962 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The method of neutron activation analysis of U by delayed-neutron counting was investigated in order to ascertain if the method would be suitable for routine application to such analyses. It was shown that the method can be used extensively and routinely for the determination of U. Emphasis was placed on the determination of U in the types of sample materials encountered in nuclear technology. Determinations of U were made on such materials as ores, granite, sea sediments, biological tissue, graphite, and metal alloys. The method is based upon the fact that delayed neutrons are emitted from fission products from the interaction of neutrons with U/sup 235/. Since the U/sup 235/ component of U undergoes most of the fissions when a sample is in a neutron flux, the method is predominately one for the determination of U/sup 235/. The total U in a sample or the isotopic composition of the U in a sample can be determined provided there is a prior knowledge of one of these quantities. The U/sup 235/ content of a test sample is obtained by comparing its delayed-neutron count to that obtained with a comparator sample containing a known quantity of U/sup 235/. (auth).
Download or read book The Use of Delayed Neutron Counting for Uranium Analysis in Biological Tissue and Its Application to a Pharmacokinetic Study in Weanling Rats written by Philip D. Nelson and published by . This book was released on 1984 with total page 198 pages. Available in PDF, EPUB and Kindle. Book excerpt: Delayed neutron counting (DNC) is a variation of neutron activation analysis applicable only to fissionable elements. Briefly, it involves exposing a sample to the neutron flux in a reactor to induce fission, then quickly retrieving the sample to count the delayed fission neutrons emitted. These are proportional to the amount of the fissionable element in the sample. This technique has been used for over two decades to assay uranium in geological and water samples. I investigated its applicability to biological tissues, specifically soft tissues and bones. Only the simplest sample preparation was required. Samples needed only to be freeze dried, weighed and encapsulated in polyvials before activation. This allowed rapid preparation of large numbers of samples at low cost (about half that of conventional chemical analyses). The minimum level of detection (MLD) for 1/2 gram samples was about 10 nanograms for natural uranium. Precision was comparable to values attained for other methods of uranium analysis. Accuracy was determined by using a relative accuracy. Prepared standard solutions were analyzed for uranium content by an outside laboratory and then all counting data were compared to these values. The effects on precision and accuracy of a variety of factors in sample preparation, activation, and neutron counting were evaluated. DNC appears to have substantial advantages for uranium analysis over conventional methods, while achieving similar precision, accuracy, and MLD. The DNC method was used to study the uptake, distribution, and clearance of an acute dose of uranium in weanling rats. The dose was administered by gavage. Animals were killed and various tissues were collected at several times post gavage. The absorption of uranium in the GI tract occurred primarily in the stomach within 15 minutes, and appeared to be dependent upon the acidity of the stomach contents. Uranium absorbed from the GI tract entered the blood and deposited in the skeleton. Uptake and loss in the skeleton followed two patterns. A transitory uptake was observed in the skull, while a slower, longer term uptake associated with bone growth or degree of bone mineralization was observed in the remainder of the skeleton. Uptake and loss in the kidney followed a similar pattern as observed for the skeleton (excluding the skull). In addition, the relative distribution of uranium in the skeleton, i.e., the fractional burdens of the individual bones of the skeleton, appeared to be independent of time post gavage, age, route of administration, and sex.
Download or read book Delayed Neutrons from U235 After Short Irradiation written by and published by . This book was released on 1949 with total page 24 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The Measurement of Uranium Concentrations by the Delayed Neutron Counting Technique written by R. I. Scherpelz and published by . This book was released on 1978 with total page 294 pages. Available in PDF, EPUB and Kindle. Book excerpt: The counting of delayed neutrons emitted by fission is presented as a valuable technique for the measurement of uranium concentrations in a variety of matrices. The concentrations successfully analyzed can vary from well under one part per million to the high concentrations found in uranium ores. In a sample analysis, fission is induced in the uranium in the sample by irradiation in a thermal neutron flux, then the sample is rapidly transferred to a counting assembly capable of detecting delayed neutrons. In the system described, irradiation is performed in a TRIGA reactor, and counting is done in a paraffin-moderated assembly of BF3 gas-filled detectors. All equipment needed for the analysis and the necessary procedures are discussed. The delayed fission neutron (DFN) counting technique is compared to other methods of analysis for uranium, and the experiences of other researchers using the DFN technique are summarized. When compared to many other methods, DFN counting is relatively free of interferences. The interferences which may occur, such as high energy gammas, unknown neutron-emitting nuclides or strong neutron absorbers in the sample, are discussed. Any uncertainties associated with a DFN measurement are also analyzed. DFN counting has been used in many applications, such as the measurement of uranium in geological samples, phosphate products and seawater adsorbers. It can also be used for the measurement of thorium in many samples. These applications are presented, and the results of many different analyses are listed. Experience gained at Oregon State University is examined in detail, and several improvements are suggested.
Download or read book Handbook of Neutron Activation Analysis written by Susan J. Parry and published by . This book was released on 2003 with total page 256 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Isotope Production And Applications In The 21st Century Proceedings Of The 3rd International Conference On Isotopes written by Nigel R Stevenson and published by World Scientific. This book was released on 2000-10-09 with total page 521 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Third International Conference on Isotopes focused on the theme of “Isotope Production and Applications in the 21st Century” and included presentations by several eminent experts in this field. The three central subjects — Isotopes in Medicine, Industry and the Environment — were supplemented by presentations on the latest developments in isotope production and synthesis, research into radiopharmaceuticals, applications in agriculture, analytical applications, radiocarbon dating, AMS and PET. Various views on the future directions for producers and users of isotopes were considered at this multi-disciplinary meeting.
Download or read book The determination of uranium by neutron irradiation and delayed neutron counting written by L. Hachkowski and published by . This book was released on 1981 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Delayed neutron counting technique for uranium determination written by Marco Antonio Zúñiga Izaguirre and published by . This book was released on 1969 with total page 102 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book A Delayed Neutron Counting System for the Analysis of Special Nuclear Materials written by Madison Theresa Sellers and published by . This book was released on 2015 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Radiochemical Analysis written by and published by . This book was released on 1964 with total page 98 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Neutron Generators for Analytical Purposes written by International Atomic Energy Agency and published by IAEA Radiation Technology Repo. This book was released on 2012 with total page 145 pages. Available in PDF, EPUB and Kindle. Book excerpt: This publication addresses recent developments in neutron generator (NG) technology. It presents information on compact instruments with high neutron yield to be used for neutron activation analysis (NAA) and prompt gamma neutron activation analysis in combination with high count rate spectrometers. Traditional NGs have been shown to be effective for applications including borehole logging, homeland security, nuclear medicine and the on-line analysis of aluminium, coal and cement. Pulsed fast thermal neutron analysis, as well as tagged and timed neutron analysis, are additional techniques which can be applied using NG. Furthermore, NG can effectively be used for elemental analysis and is also effective for analysis of hidden materials by neutron radiography. Useful guidelines for developing NG based research laboratories are also provided in this publication.
Download or read book Applications of Research Reactors written by International Atomic Energy Agency and published by International Atomic Energy Agency. This book was released on 2014 with total page 108 pages. Available in PDF, EPUB and Kindle. Book excerpt: This publication is a comprehensive study that reviews the current situation in a great number of applications of research reactors. It revises the contents of IAEA TECDOC-1234, The Applications of Research Reactors, giving detailed updates on each field of research reactor uses worldwide. Reactors of all sizes and capabilities can benefit from the sharing of current practices and research enabled via this updated version, which describes the requirements for practicing methods as diverse as neutron activation analysis, education and training, neutron scattering and neutron imaging, silicon doping and radioisotope production, material/fuel irradiation and testing, and some others. Many underutilised research reactors can learn how to diversify their technical capabilities, staff and potential commercial partners and users seeking research reactor services and products. The content of the publication has also been strengthened in terms of current issues facing the vast majority of research reactors by including sections describing user and customer relations as well as strategic planning considerations.
Download or read book NBS Technical Note written by and published by . This book was released on 1959 with total page 904 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Publications Reports and Papers for 1961 from Oak Ridge National Laboratory written by Oak Ridge National Laboratory and published by . This book was released on 1961 with total page 256 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book WASH written by and published by . This book was released on 1972 with total page 100 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book NUREG CR written by U.S. Nuclear Regulatory Commission and published by . This book was released on 1981 with total page 292 pages. Available in PDF, EPUB and Kindle. Book excerpt:
