Tracking the Isotopes
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Neutron Interactions and Dosimetry Outline Introduction Tissue
Outline • Neutron dosimetry Neutron Interactions and – Thermal neutrons Dosimetry – Intermediate-energy neutrons – Fast neutrons Chapter 16 • Sources of neutrons • Mixed field dosimetry, paired dosimeters F.A. Attix, Introduction to Radiological • Rem meters Physics and Radiation Dosimetry Introduction Tissue composition • Consider neutron interactions with the majority tissue elements H, O, C, and N, and the resulting absorbed dose • Because of the short ranges of the secondary charged particles that are produced in such interactions, CPE is usually well approximated • Since no bremsstrahlung x-rays are generated, the • The ICRU composition for muscle has been assumed in absorbed dose can be assumed to be equal to the most cases for neutron-dose calculations, lumping the kerma at any point in neutron fields at least up to 1.1% of “other” minor elements together with oxygen to an energy E ~ 20 MeV make a simple four-element (H, O, C, N) composition Neutron kinetic energy Neutron kinetic energy • Neutron fields are divided into three • Thermal neutrons, by definition, have the most probable categories based on their kinetic energy: kinetic energy E=kT=0.025eV at T=20C – Thermal (E<0.5 eV) • Neutrons up to 0.5eV are considered “thermal” due to simplicity of experimental test after they emerge from – Intermediate-energy (0.5 eV<E<10 keV) moderator material – Fast (E>10 keV) • Cadmium ratio test: • Differ by their primary interactions in tissue – Gold foil can be activated through 197Au(n,)198Au interaction and resulting biological effects -
Hitler and Heisenberg
The Wall Street Journal December 27-28, 2014 Book Review “Serving the Reich” by Philip Ball, Chicago, $30, 303 pages Hitler and Heisenberg Werner Heisenberg thought that once Germany had won, the ‘good Germans’ would get rid of the Nazis. Fizzing The museum inside the former basement tavern where in early 1945 German scientists built a small nuclear reactor. Associated Press by Jeremy Bernstein The German scientists who remained in Germany throughout the Nazi period can be divided into three main groups. At one end were the anti-Nazis—people who not only despised the regime but tried to do something about it. They were very few. Two that come to mind were Fritz Strassmann and Max von Laue. Strassmann was a radiochemist—a specialist in radioactive materials—who was blacklisted from university jobs by the Society of German Chemists in 1933 for his anti-Nazi views. He was fortunate to get a half-pay job at the Kaiser Wilhelm Institute for Chemistry, which got some of its funding from industry. He and his wife (they had a 3-year-old son) hid a Jewish friend in their apartment for months. With the radiochemist Otto Hahn, he performed the 1938 experiment in which fission was observed for the first time. Von Laue won the Nobel Prize in physics in 1914. Soon after Einstein published his 1905 paper on relativity, von Laue went to Switzerland to see him. They remained friends for life. Under the Nazis, Einstein’s work was denounced as “Jewish science.” When a number of von Laue’s colleagues agreed to use relativity but attribute it to some Aryan, he refused. -
NOBELIUM Element Symbol: No Atomic Number: 102
NOBELIUM Element Symbol: No Atomic Number: 102 An initiative of IYC 2011 brought to you by the RACI KERRY LAMB www.raci.org.au NOBELIUM Element symbol: No Atomic number: 102 The credit for discovering Nobelium was disputed with 3 different research teams claiming the discovery. While the first claim dates back to 1957, it was not until 1992 that the International Union of Pure and Applied Chemistry credited the discovery to a research team from Dubna in Russia for work they did in 1966. The element was named Nobelium in 1957 by the first of its claimed discoverers (the Nobel Institute in Sweden). It was named after Alfred Nobel, a Swedish chemist who invented dynamite, held more than 350 patents and bequeathed his fortune to the establishment of the Nobel Prizes. Nobelium is a synthetic element and does not occur in nature and has no known uses other than in scientific research as only tiny amounts of the element have ever been produced. Nobelium is radioactive and most likely metallic. The appearance and properties of Nobelium are unknown as insufficient amounts of the element have been produced. Nobelium is made by the bombardment of curium (Cm) with carbon nuclei. Its most stable isotope, 259No, has a half-life of 58 minutes and decays to Fermium (255Fm) through alpha decay or to Mendelevium (259Md) through electron capture. Provided by the element sponsor Freehills Patent and Trade Mark Attorneys ARTISTS DESCRIPTION I wanted to depict Alfred Nobel, the namesake of Nobelium, as a resolute young man, wearing the Laurel wreath which is the symbol of victory. -
Hetc-3Step Calculations of Proton Induced Nuclide Production Cross Sections at Incident Energies Between 20 Mev and 5 Gev
JAERI-Research 96-040 JAERI-Research—96-040 JP9609132 JP9609132 HETC-3STEP CALCULATIONS OF PROTON INDUCED NUCLIDE PRODUCTION CROSS SECTIONS AT INCIDENT ENERGIES BETWEEN 20 MEV AND 5 GEV August 1996 Hiroshi TAKADA, Nobuaki YOSHIZAWA* and Kenji ISHIBASHI* Japan Atomic Energy Research Institute 2 G 1 0 1 (T319-11 l This report is issued irregularly. Inquiries about availability of the reports should be addressed to Research Information Division, Department of Intellectual Resources, Japan Atomic Energy Research Institute, Tokai-mura, Naka-gun, Ibaraki-ken, 319-11, Japan. © Japan Atomic Energy Research Institute, 1996 JAERI-Research 96-040 HETC-3STEP Calculations of Proton Induced Nuclide Production Cross Sections at Incident Energies between 20 MeV and 5 GeV Hiroshi TAKADA, Nobuaki YOSHIZAWA* and Kenji ISHIBASHP* Department of Reactor Engineering Tokai Research Establishment Japan Atomic Energy Research Institute Tokai-mura, Naka-gun, Ibaraki-ken (Received July 1, 1996) For the OECD/NEA code intercomparison, nuclide production cross sections of l60, 27A1, nalFe, 59Co, natZr and 197Au for the proton incidence with energies of 20 MeV to 5 GeV are calculated with the HETC-3STEP code based on the intranuclear cascade evaporation model including the preequilibrium and high energy fission processes. In the code, the level density parameter derived by Ignatyuk, the atomic mass table of Audi and Wapstra and the mass formula derived by Tachibana et al. are newly employed in the evaporation calculation part. The calculated results are compared with the experimental ones. It is confirmed that HETC-3STEP reproduces the production of the nuclides having the mass number close to that of the target nucleus with an accuracy of a factor of two to three at incident proton energies above 100 MeV for natZr and 197Au. -
Submission to the Nuclear Power Debate Personal Details Kept Confidential
Submission to the Nuclear power debate Personal details kept confidential __________________________________________________________________________________________ Firstly I wish to say I have very little experience in nuclear energy but am well versed in the renewable energy one. What we need is a sound rational debate on the future energy requirements of Australia. The calls for cessation of nuclear investigations even before a debate begins clearly shows that emotion rather than facts are playing a part in trying to stop the debate. Future energy needs must be compliant to a sound strategy of consistent, persistent energy supply. This cannot come from wind or solar. Lets say for example a large blocking high pressure weather system sits over the Victorian, NSW land masses in late summer- autumn season. We will see low winds for anything up to a week, can the energy market from the other states support the energy needs of these states without coal or gas? I think not. France has a large investment in nuclear energy and charges their citizens around half as much for it than Germany. Sceptics complain about the costs of storage of waste, they do not suggest what is going to happen to all the costs to the environment when renewing of derelict solar panels and wind turbine infrastructure which is already reaching its use by dates. Sceptics also talk about the dangers of nuclear energy using Chernobyl, Three Mile Island and Fuklushima as examples. My goodness given that same rationale then we should have banned flight after the first plane accident or cars after the first car accident. -
Royal Society of Chemistry Input to the Ad Hoc Nuclear
ROYAL SOCIETY OF CHEMISTRY INPUT TO THE AD HOC NUCLEAR RESEARCH AND DEVELOPMENT ADVISORY BOARD The Royal Society of Chemistry (RSC) was pleased to hear of the instigation of the Ad Hoc Nuclear Research and Development Advisory Board (the Board) following the findings of the House of Lords Science and Technology Committee Inquiry ‘Nuclear Research and Development Capabilities’.1,2 The RSC is the largest organisation in Europe for advancing the chemical sciences. Supported by a network of 47,000 members worldwide and an internationally acclaimed publishing business, its activities span education and training, conferences and science policy, and the promotion of the chemical sciences to the public. This document represents the views of the RSC. The RSC has a duty under its Royal Charter "to serve the public interest" by acting in an independent advisory capacity, and it is in this spirit that this submission is made. To provide input to the Board the RSC has performed a wide consultation with the chemical science community, including members of both our Radiochemistry and Energy Sector Interest Groups and also our Environment Sustainability and Energy Division. September 2012 The Role of Chemistry in a Civil Nuclear Strategy 1 Introduction Chemistry and chemical knowledge is essential in nuclear power generation and nuclear waste management. It is essential that a UK civil nuclear strategy recognises the crucial role that chemistry plays, both in research and innovation and in the development of a strong skills pipeline. As the RSC previously articulated in our response to the House of Lords Inquiry, 3 nuclear power is an important component of our current energy mix. -
An Octad for Darmstadtium and Excitement for Copernicium
SYNOPSIS An Octad for Darmstadtium and Excitement for Copernicium The discovery that copernicium can decay into a new isotope of darmstadtium and the observation of a previously unseen excited state of copernicium provide clues to the location of the “island of stability.” By Katherine Wright holy grail of nuclear physics is to understand the stability uncover its position. of the periodic table’s heaviest elements. The problem Ais, these elements only exist in the lab and are hard to The team made their discoveries while studying the decay of make. In an experiment at the GSI Helmholtz Center for Heavy isotopes of flerovium, which they created by hitting a plutonium Ion Research in Germany, researchers have now observed a target with calcium ions. In their experiments, flerovium-288 previously unseen isotope of the heavy element darmstadtium (Z = 114, N = 174) decayed first into copernicium-284 and measured the decay of an excited state of an isotope of (Z = 112, N = 172) and then into darmstadtium-280 (Z = 110, another heavy element, copernicium [1]. The results could N = 170), a previously unseen isotope. They also measured an provide “anchor points” for theories that predict the stability of excited state of copernicium-282, another isotope of these heavy elements, says Anton Såmark-Roth, of Lund copernicium. Copernicium-282 is interesting because it University in Sweden, who helped conduct the experiments. contains an even number of protons and neutrons, and researchers had not previously measured an excited state of a A nuclide’s stability depends on how many protons (Z) and superheavy even-even nucleus, Såmark-Roth says. -
Re-Examining the Role of Nuclear Fusion in a Renewables-Based Energy Mix
Re-examining the Role of Nuclear Fusion in a Renewables-Based Energy Mix T. E. G. Nicholasa,∗, T. P. Davisb, F. Federicia, J. E. Lelandc, B. S. Patela, C. Vincentd, S. H. Warda a York Plasma Institute, Department of Physics, University of York, Heslington, York YO10 5DD, UK b Department of Materials, University of Oxford, Parks Road, Oxford, OX1 3PH c Department of Electrical Engineering and Electronics, University of Liverpool, Liverpool, L69 3GJ, UK d Centre for Advanced Instrumentation, Department of Physics, Durham University, Durham DH1 3LS, UK Abstract Fusion energy is often regarded as a long-term solution to the world's energy needs. However, even after solving the critical research challenges, engineer- ing and materials science will still impose significant constraints on the char- acteristics of a fusion power plant. Meanwhile, the global energy grid must transition to low-carbon sources by 2050 to prevent the worst effects of climate change. We review three factors affecting fusion's future trajectory: (1) the sig- nificant drop in the price of renewable energy, (2) the intermittency of renewable sources and implications for future energy grids, and (3) the recent proposition of intermediate-level nuclear waste as a product of fusion. Within the scenario assumed by our premises, we find that while there remains a clear motivation to develop fusion power plants, this motivation is likely weakened by the time they become available. We also conclude that most current fusion reactor designs do not take these factors into account and, to increase market penetration, fu- sion research should consider relaxed nuclear waste design criteria, raw material availability constraints and load-following designs with pulsed operation. -
Compilation and Evaluation of Fission Yield Nuclear Data Iaea, Vienna, 2000 Iaea-Tecdoc-1168 Issn 1011–4289
IAEA-TECDOC-1168 Compilation and evaluation of fission yield nuclear data Final report of a co-ordinated research project 1991–1996 December 2000 The originating Section of this publication in the IAEA was: Nuclear Data Section International Atomic Energy Agency Wagramer Strasse 5 P.O. Box 100 A-1400 Vienna, Austria COMPILATION AND EVALUATION OF FISSION YIELD NUCLEAR DATA IAEA, VIENNA, 2000 IAEA-TECDOC-1168 ISSN 1011–4289 © IAEA, 2000 Printed by the IAEA in Austria December 2000 FOREWORD Fission product yields are required at several stages of the nuclear fuel cycle and are therefore included in all large international data files for reactor calculations and related applications. Such files are maintained and disseminated by the Nuclear Data Section of the IAEA as a member of an international data centres network. Users of these data are from the fields of reactor design and operation, waste management and nuclear materials safeguards, all of which are essential parts of the IAEA programme. In the 1980s, the number of measured fission yields increased so drastically that the manpower available for evaluating them to meet specific user needs was insufficient. To cope with this task, it was concluded in several meetings on fission product nuclear data, some of them convened by the IAEA, that international co-operation was required, and an IAEA co-ordinated research project (CRP) was recommended. This recommendation was endorsed by the International Nuclear Data Committee, an advisory body for the nuclear data programme of the IAEA. As a consequence, the CRP on the Compilation and Evaluation of Fission Yield Nuclear Data was initiated in 1991, after its scope, objectives and tasks had been defined by a preparatory meeting. -
Experiments on the Application of Autoradiographic Techniques to the Study of Problems in Plant Physiology
EXPERIMENTS ON THE APPLICATION OF AUTORADIOGRAPHIC TECHNIQUES TO THE STUDY OF PROBLEMS IN PLANT PHYSIOLOGY By R. THAINE4 and MADELINE C. W ALTERst [Manuscript received March 28, 1955] Summary A method of autoradiography has been developed which allows the record of single ,a-particles emitted from sections of plant tissue 5-7 ~L thick. The method allows resolution of the order of 1 ~ and magnification up to x 1500. Dissolution of the water and alcohol soluble contents of the tissue has been overcome, and it is therefore possible to determine the distribution of com pounds concerned in the metabolism and biosynthesis of a cell. Cellular dis tortion and loss of contents during fixation and photographic processing is illus trated, and it is hoped that an improved method of freeze-drying· will reduce this limitation. In macroscopic autoradiography the soya bean has proved to be most valuable plant material, because the thin stems and leaves allow auto graphs which give a detailed record of the transported compounds containing 14C. The isotope is introduced to the plant in the photosynthesis of 14C02, and after a suitable period, the plant is dissected, dried, and placed against X-ray film. After 14 days exposure the film is developed, and the photographic image records positions and relative concentration of the isotope in the plant tissue. I. INTRODUCTION The earliest experiments with radioactive tracers in plants were confined to a study of the macroscopic distribution of certain substances, such as phos phorus, which could be readily labelled, and successful autoradiographs of leaves and fruits were obtained (Arnon, Stout, and Sipos 1940; Colwell 1942; Harrison, Thomas, and Hill 1944; Grosse and Snyder 1947). -
Concrete Analysis by Neutron-Capture Gamma Rays Using Californium 252
CONCRETE ANALYSIS BY NEUTRON-CAPTURE GAMMA RAYS USING CALIFORNIUM 252 Dick Duffey, College of Engineering, University of Maryland; Peter F. Wiggins, Naval Systems Engineering Department, U.S. Naval Academy; Frank E. Senftle, U.S. Geological Survey; and A. A. El Kady, United Arab Republic Atomic Energy Establishment, Cairo The feasibility of analyzing concrete and cement by a measurement of the neutron-capture or prompt gamma rays was investigated; a 100-ug californium-252 source was used to supply the neutrons. A lithium drifted germanium crystal detected the capture gamma rays emitted. The capture gamma rays from cement, sand, and 3 coarse aggregates-quartzite gravel, limestone, and diabase--:were studied. Concrete blocks made from these materials were then tested. The capture gamma ray response of the calcium, silicon, and iron in the concrete blocks was in accord with the elements identified in the mix materials. The principal spectral lines used were the 6.42 MeV line of calcium, the 4.93 MeV line of silicon, and the doublet of iron at about 7 .64 MeV. The aluminum line at 7. 72 MeV was ob served in some cases but at a lower intensity with the limited electronic equipment available. This nuclear spectroscopic technique offers a possi ble method of determining the components of sizable concrete samples in a nondestructive, in situ manner. In addition, the neutron-capture gamma ray technique might find application in control of the concrete and cement processes and furnish needed information on production operations and inventories. • FROM THE point of view of the geochemical analyst, concrete may be considered as rock relocated and reformed at the convenience of the engineer. -
Nuclear Chemistry Card Sort
Nuclear Chemistry Card Sort Submitted by: Annette Gillespie, Ashely Gilomen, Sarah Johnson, and Stephanie Kimberlin Appalachian Regional Commission/Oak Ridge National Laboratory Summer Math-Science-Technology Institute Grade: 9-12 Lesson Duration: 45-60 minutes Materials Needed: • Media for Venn Diagram (e.g., poster board, white board, butcher paper, electronic devices) • One copy of the list of nuclear chemistry concepts/nuclear chemistry concept cards provided in this lesson plan • Envelope for storing cut-up list/cards Background Information: Students should be able to describe the basic structure of an atom and have a basic understanding of nuclear notation. Lesson Objective: Students will be able to • Describe the basic principles of nuclear chemistry. • Discern between diagrams and representations of nuclear equations and processes. • Use context clues to correctly categorize nuclear events. Instructional Process: All informative resources should be made available to the students so they can categorize the concepts (e.g., notes, text books, Internet). This lesson is best suited as an introduction activity for the beginning of the nuclear chemistry unit and/or as a review activity at the end of the nuclear chemistry unit. Students should be organized into groups of 3-4 to complete this activity. Each student group should create and label a three-circle Venn diagram on the teacher-designated media. (Refer to the examples provided in figure 1 and at the end of this lesson plan.) Each group should receive one copy of the list of nuclear chemistry concepts/nuclear chemistry concept cards, which they will cut up into individual cards. Once students have their diagrams drawn and cards cut out, they should place the nuclear chemistry concepts cards into one of three categories on the diagram: fission, fusion, or nuclear decay.