8 the Chemical Toxicity of Uranium 8.1 Introduction
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The Excretion and Storage of Ammonia by the Aquatic Larva of Sialis Lutaria (Neuroptera)
THE EXCRETION AND STORAGE OF AMMONIA BY THE AQUATIC LARVA OF SIALIS LUTARIA (NEUROPTERA) BY B. W. STADDON* Department of Zoology, University of Durham, King's College, Newcastle upon Tyne (Received 12 April 1954) INTRODUCTION Delaunay (1931), in a review of the invertebrates, showed that an excellent correla- tion existed between the nature of the major nitrogenous component of the excreta and the nature of the environment, aquatic or terrestrial, in which an animal lived. Ammonia was shown to predominate in the excreta of aquatic species, urea or uric acid in the excreta of semi-terrestrial or terrestrial species. Delaunay put forward the view that the synthesis by these terrestrial forms of more complex molecules from ammonia was essentially a detoxication mechanism necessitated by a restricted water supply. Although the insects are primarily a terrestrial group, representatives of a number of orders have become aquatic in one or more stages of their life histories. It is well known that those terrestrial species which have been examined, with the notable exception of blowfly larvae, excrete the bulk of their nitrogen in the form of uric acid (Wigglesworth, 1950). The possibility, however, that aquatic species might have reverted to ammonotelism does not seem to have been examined. Preliminary tests were carried out on the excreta of a variety of aquatic insects. In all cases ammonia was found to be the major nitrogenous excretory product. An investigation into various aspects of the metabolism, toxicity and excretion of ammonia was then undertaken on the aquatic larva of Siatis lutaria. It is the purpose of the present communication to present some observations on the excretion and storage of ammonia in this species. -
In Vitro Interactions of Epacadostat and Its Major Metabolites With
DMD Fast Forward. Published on March 10, 2017 as DOI: 10.1124/dmd.116.074609 This article has not been copyedited and formatted. The final version may differ from this version. DMD # 74609 In vitro interactions of epacadostat and its major metabolites with human efflux and uptake transporters: Implications for pharmacokinetics and drug interactions Qiang Zhang, Yan Zhang, Jason Boer, Jack G. Shi, Peidi Hu, Sharon Diamond, and Downloaded from Swamy Yeleswaram Incyte Corporation, Wilmington, DE 19803 dmd.aspetjournals.org at ASPET Journals on September 29, 2021 1 DMD Fast Forward. Published on March 10, 2017 as DOI: 10.1124/dmd.116.074609 This article has not been copyedited and formatted. The final version may differ from this version. DMD # 74609 Running title: Interactions of Epacadostat with Transporters Corresponding Author: Qiang Zhang, Ph.D. Incyte Corporation 1801 Augustine Cut-Off Wilmington, DE 19803 Downloaded from Email: [email protected] Phone: 302-498-5827 Fax: 302-425-2759 dmd.aspetjournals.org Number of Text Pages: 24 Number of Figures: 8 at ASPET Journals on September 29, 2021 Number of Tables: 6 Number of References: 24 The number of words of Abstract: 247 The number of words of Introduction: 655 The number of words of Discussion: 1487 Non-standard Abbreviations: EPAC, epacadostat; IDO1, indoleamine 2,3-dioxygenase 1; EHC, enterohepatic circulation; NME, new chemical entity; TEER, transepithelial electrical resistance; HBSS, Hank's Balanced Salt Solution; KO, knockout; CSA, cyclosporin A; IC50, half-maximal inhibitory concentration; ER, efflux ratio 2 DMD Fast Forward. Published on March 10, 2017 as DOI: 10.1124/dmd.116.074609 This article has not been copyedited and formatted. -
Measurement of Uranium Dioxide Thermophysical Properties by the Laser Flash Method
2009 International Nuclear Atlantic Conference - INAC 2009 Rio de Janeiro,RJ, Brazil, September27 to October 2, 2009 ASSOCIAÇÃO BRASILEIRA DE ENERGIA NUCLEAR - ABEN ISBN: 978-85-99141-03-8 MEASUREMENT OF URANIUM DIOXIDE THERMOPHYSICAL PROPERTIES BY THE LASER FLASH METHOD Pablo Andrade Grossi 1, Ricardo Alberto Neto Ferreira 2, Denise das Mercês Camarano 3, Roberto Márcio de Andrade 4 1,2,3 Centro de Desenvolvimento da Tecnologia Nuclear-CDTN Comissão Nacional de Energia Nuclear-CNEN Av. Presidente Antônio Carlos 6627 Cidade Universitária-Pampulha-Caixa Postal 941 CEP: 31.161-970 Belo Horizonte, MG 1 [email protected] 2 [email protected] 3 [email protected] 4 Departamento de Engenharia Mecânica Escola de Engenharia da Universidade Federal de Minas Gerais Av. Presidente Antônio Carlos 6627-Cidade Universitária-Pampulha CEP: 31.270-901 - Belo Horizonte – MG - Brasil 4 [email protected] ABSTRACT The evaluation of the thermophysical properties of uranium dioxide (UO 2), including a reliable uncertainty assessment, are required by the nuclear reactor design. These important informations are used by thermohydraulic codes to define operational aspects and to assure the safety, when analyzing various potential situations of accident. The Laser Flash Method had become the most popular method to measure the thermophysical properties of materials. Despite its several advantages, some experimental obstacles have been found due to the difficulty to obtain experimentally the ideals initial and boundary conditions required by the original method. An experimental apparatus and a methodology for estimating uncertainties of thermal diffusivity, thermal conductivity and specific heat measurements based on the Laser Flash Method are presented. A stochastic thermal diffusion modeling has been developed and validated by Standard Samples. -
Depleted Uranium Technical Brief
Disclaimer - For assistance accessing this document or additional information,please contact [email protected]. Depleted Uranium Technical Brief United States Office of Air and Radiation EPA-402-R-06-011 Environmental Protection Agency Washington, DC 20460 December 2006 Depleted Uranium Technical Brief EPA 402-R-06-011 December 2006 Project Officer Brian Littleton U.S. Environmental Protection Agency Office of Radiation and Indoor Air Radiation Protection Division ii iii FOREWARD The Depleted Uranium Technical Brief is designed to convey available information and knowledge about depleted uranium to EPA Remedial Project Managers, On-Scene Coordinators, contractors, and other Agency managers involved with the remediation of sites contaminated with this material. It addresses relative questions regarding the chemical and radiological health concerns involved with depleted uranium in the environment. This technical brief was developed to address the common misconception that depleted uranium represents only a radiological health hazard. It provides accepted data and references to additional sources for both the radiological and chemical characteristics, health risk as well as references for both the monitoring and measurement and applicable treatment techniques for depleted uranium. Please Note: This document has been changed from the original publication dated December 2006. This version corrects references in Appendix 1 that improperly identified the content of Appendix 3 and Appendix 4. The document also clarifies the content of Appendix 4. iv Acknowledgments This technical bulletin is based, in part, on an engineering bulletin that was prepared by the U.S. Environmental Protection Agency, Office of Radiation and Indoor Air (ORIA), with the assistance of Trinity Engineering Associates, Inc. -
Sources, Effects and Risks of Ionizing Radiation
SOURCES, EFFECTS AND RISKS OF IONIZING RADIATION United Nations Scientific Committee on the Effects of Atomic Radiation UNSCEAR 2016 Report to the General Assembly, with Scientific Annexes UNITED NATIONS New York, 2017 NOTE The report of the Committee without its annexes appears as Official Records of the General Assembly, Seventy-first Session, Supplement No. 46 and corrigendum (A/71/46 and Corr.1). The report reproduced here includes the corrections of the corrigendum. The designations employed and the presentation of material in this publication do not imply the expression of any opinion whatsoever on the part of the Secretariat of the United Nations concerning the legal status of any country, territory, city or area, or of its authorities, or concerning the delimitation of its frontiers or boundaries. The country names used in this document are, in most cases, those that were in use at the time the data were collected or the text prepared. In other cases, however, the names have been updated, where this was possible and appropriate, to reflect political changes. UNITED NATIONS PUBLICATION Sales No. E.17.IX.1 ISBN: 978-92-1-142316-7 eISBN: 978-92-1-060002-6 © United Nations, January 2017. All rights reserved, worldwide. This publication has not been formally edited. Information on uniform resource locators and links to Internet sites contained in the present publication are provided for the convenience of the reader and are correct at the time of issue. The United Nations takes no responsibility for the continued accuracy of that information or for the content of any external website. -
High-Density Concrete with Ceramic Aggregate Based on Depleted Uranium Dioxide
HIGH-DENSITY CONCRETE WITH CERAMIC AGGREGATE BASED ON DEPLETED URANIUM DIOXIDE S.G. Ermichev, V.I. Shapovalov, N.V.Sviridov (RFNC-VNIIEF, Sarov, Russia) V.K. Orlov, V.M. Sergeev, A. G. Semyenov, A.M. Visik, A.A. Maslov, A. V. Demin, D.D. Petrov, V.V. Noskov, V. I. Sorokin, O. I. Uferov (VNIINM, Moscow, Russia) L. Dole (ORNL, Oak Ridge, USA) Abstract - Russia is researching the production and testing of concretes with ceramic aggregate based on depleted uranium dioxide (UO2). These DU concretes are to be used as structural and radiation-shielded material for casks for A-plant spent nuclear fuel transportation and storage. This paper presents the results of studies aimed at selection of ceramics and concrete composition, justification of their production technology, investigation of mechanical properties, and chemical stability. This Project is being carried out at the A.A. Bochvar All-Russian Scientific-Research Institute of inorganic materials (VNIINM, Russia) and Russian Federal Nuclear Center – All-Russia Scientific Research Institute of Experimental Physics (RFNC-VNIIEF, Russia). This Project #2691 is financed by the International Science and Technology Center (ISTC) under collaboration of the Oak- Ridge National Laboratory (USA) I. INTRODUCTION The current practice of ensuring the required gamma conduction, thermo-, radiation and corrosion resistance, shielding and strength of metal-concrete casks is based on service life and water resistance. concrete density. For this purpose high-density rocks Specific characteristics of UO2’s chemical activity (magnetite, iron glance, barium sulfate, etc.) as well as because of its small size of particles and thus great specific scrap, scale, broken metal chips and others are introduced surface area prevent the use of traditional methods of UO2 into concrete as coarse aggregates. -
I -F??TI O08'w –Gçanooog –Ggan
Feb. 27, 1962 L. BURRIS, JR., ETA 3,023,097 REPROCESSING URANIUM DIOXDE FUES Filed Nov. 23, 1959 2 Sheets-Sheet I-F??TI OOOG–ggan O08’w–gçan no?opa8 (g?20%OG) INVENTOR. Les lie 8urris, Jr. Af r e di S c h n e i der Attorney Feb. 27, 1962 L. BURRIS, JR., ETA 3,023,097 REPROCESSING URANIUM DIOXDE FUELS Filed Nov. 23, 1959 2 Sheets-Sheet 2 - 4O - 5 ? - 6 O - 8O - 9 O - OO - , ? - 2 O - 3 O Nd 2O Gnd Sm2O3 - 4 O - 150 Pr2O3 and Ce2O3 O 3OO 5OO IOOO 5OO 2OOO 25 OO Temperature (K) F I Leslie Burris,INVENTOR. Jr. Alfred Schneid er BY ????? C???-e Attorney - 3,023,097 United States Patent Office Patented Feb. 27, 1962 2 of the dioxide fuel and its commingled substances in prep 3,323,097 aration for the next step about to be described; this size REPROCESSING GUARNUM DIXE FUELS Lesie Burris, Jr., and Alfred Schneider, Naperville, H., reduction is best carried out by successive oxidations and aSsigi nors to the United States of America as rere reductions which cause crumbling by reason of the suc sented by the United States Atomic Energy Cons cessive changes in crystal structure. After the particle ?$$??? size has been reduced sufficiently, a molten reducing i Fied Nov. 23, 1959, Ser. No. 854,989 metal of the group consisting of zinc and cadmium is 4 Claims. (C. 75-84.) introduced to the crumbled mixture, and this causes quite a number of metals to go into the metallic state, where The invention relates to a novel pyrometalurgical O upon they alloy with the reducing metal and the molten method of reprocessing uranium dioxide fuels after they metal phase may then be separated from the solid oxide have become contaminated by ª fission products in i nu phase consisting of the oxides of metals such as uranium, clear reactors, and more particularly, to a novel method rare earths and plutonium which are still not reduced. -
Dissolution of Uranium Dioxide in Nitric Acid Media: What Do We Know?
EPJ Nuclear Sci. Technol. 3, 13 (2017) Nuclear © Sciences P. Marc et al., published by EDP Sciences, 2017 & Technologies DOI: 10.1051/epjn/2017005 Available online at: http://www.epj-n.org REGULAR ARTICLE Dissolution of uranium dioxide in nitric acid media: what do we know? Philippe Marc1, Alastair Magnaldo1,*, Aimé Vaudano1, Thibaud Delahaye2, and Éric Schaer3 1 CEA, Nuclear Energy Division, Research Department of Mining and Fuel Recycling Processes, Service of Dissolution and Separation Processes, Laboratory of Dissolution Studies, 30207 Bagnols-sur-Cèze, France 2 CEA, Nuclear Energy Division, Research Department of Mining and Fuel Recycling Processes, Service of Actinides Materials Fabrication, Laboratory of Actinide Conversion Processes, 30207 Bagnols-sur-Cèze, France 3 Laboratoire Réactions et Génie des Procédés, UMR CNRS 7274, University of Lorraine, 54001 Nancy, France Received: 16 March 2016 / Received in final form: 15 November 2016 / Accepted: 14 February 2017 Abstract. This article draws a state of knowledge of the dissolution of uranium dioxide in nitric acid media. The chemistry of the reaction is first investigated, and two reactions appear as most suitable to describe the mechanism, leading to the formation of monoxide and dioxide nitrogen as reaction by-products, while the oxidation mechanism is shown to happen before solubilization. The solid aspect of the reaction is also investigated: manufacturing conditions have an impact on dissolution kinetics, and the non-uniform attack at the surface of the solid results in the appearing of pits and cracks. Last, the existence of an autocatalytic mechanism is questionned. The second part of this article presents a compilation of the impacts of several physico-chemical parameters on the dissolution rates. -
TOXICOLOGY and EXPOSURE GUIDELINES ______(For Assistance, Please Contact EHS at (402) 472-4925, Or Visit Our Web Site At
(Revised 1/03) TOXICOLOGY AND EXPOSURE GUIDELINES ______________________________________________________________________ (For assistance, please contact EHS at (402) 472-4925, or visit our web site at http://ehs.unl.edu/) "All substances are poisons; there is none which is not a poison. The right dose differentiates a poison and a remedy." This early observation concerning the toxicity of chemicals was made by Paracelsus (1493- 1541). The classic connotation of toxicology was "the science of poisons." Since that time, the science has expanded to encompass several disciplines. Toxicology is the study of the interaction between chemical agents and biological systems. While the subject of toxicology is quite complex, it is necessary to understand the basic concepts in order to make logical decisions concerning the protection of personnel from toxic injuries. Toxicity can be defined as the relative ability of a substance to cause adverse effects in living organisms. This "relative ability is dependent upon several conditions. As Paracelsus suggests, the quantity or the dose of the substance determines whether the effects of the chemical are toxic, nontoxic or beneficial. In addition to dose, other factors may also influence the toxicity of the compound such as the route of entry, duration and frequency of exposure, variations between different species (interspecies) and variations among members of the same species (intraspecies). To apply these principles to hazardous materials response, the routes by which chemicals enter the human body will be considered first. Knowledge of these routes will support the selection of personal protective equipment and the development of safety plans. The second section deals with dose-response relationships. -
Uranium-Free X Solution
www.nature.com/scientificreports OPEN Uranium‑free X solution: a new generation contrast agent for biological samples ultrastructure Aldo Moscardini1,6, Sebastiano Di Pietro 2,6, Giovanni Signore3*, Paola Parlanti4, Melissa Santi5, Mauro Gemmi5 & Valentina Cappello5* Biological samples are mainly composed of elements with a low atomic number which show a relatively low electron scattering power. For Transmission Electron Microscopy analysis, biological samples are generally embedded in resins, which allow thin sectioning of the specimen. Embedding resins are also composed by light atoms, thus the contrast diference between the biological sample and the surrounding resin is minimal. Due to that reason in the last decades, several staining solutions and approaches, performed with heavy metal salts, have been developed with the purpose of enhancing both the intrinsic sample contrast and the diferences between the sample and resin. The best staining was achieved with the uranyl acetate (UA) solution, which has been the election method for the study of morphology in biological samples. More recently several alternatives for UA have been proposed to get rid of its radiogenic issues, but to date none of these solutions has achieved efciencies comparable to UA. In this work, we propose a diferent staining solution (X Solution or X SOL), characterized by lanthanide polyoxometalates (LnPOMs) as heavy atoms source, which could be used alternatively to UA in negative staining (NS), in en bloc staining, and post sectioning staining (PSS) of biological samples. Furthermore, we show an extensive chemical characterization of the LnPOM species present in the solution and the detailed work for its fnal formulation, which brought remarkable results, and even better performances than UA. -
Biotransformation: Basic Concepts (1)
Chapter 5 Absorption, Distribution, Metabolism, and Elimination of Toxics Biotransformation: Basic Concepts (1) • Renal excretion of chemicals Biotransformation: Basic Concepts (2) • Biological basis for xenobiotic metabolism: – To convert lipid-soluble, non-polar, non-excretable forms of chemicals to water-soluble, polar forms that are excretable in bile and urine. – The transformation process may take place as a result of the interaction of the toxic substance with enzymes found primarily in the cell endoplasmic reticulum, cytoplasm, and mitochondria. – The liver is the primary organ where biotransformation occurs. Biotransformation: Basic Concepts (3) Biotransformation: Basic Concepts (4) • Interaction with these enzymes may change the toxicant to either a less or a more toxic form. • Generally, biotransformation occurs in two phases. – Phase I involves catabolic reactions that break down the toxicant into various components. • Catabolic reactions include oxidation, reduction, and hydrolysis. – Oxidation occurs when a molecule combines with oxygen, loses hydrogen, or loses one or more electrons. – Reduction occurs when a molecule combines with hydrogen, loses oxygen, or gains one or more electrons. – Hydrolysis is the process in which a chemical compound is split into smaller molecules by reacting with water. • In most cases these reactions make the chemical less toxic, more water soluble, and easier to excrete. Biotransformation: Basic Concepts (5) – Phase II reactions involves the binding of molecules to either the original toxic molecule or the toxic molecule metabolite derived from the Phase I reactions. The final product is usually water soluble and, therefore, easier to excrete from the body. • Phase II reactions include glucuronidation, sulfation, acetylation, methylation, conjugation with glutathione, and conjugation with amino acids (such as glycine, taurine, and glutamic acid). -
Circular of the Bureau of Standards No
t9?2 fcixt .Wii * S/ DEPARTMENT OF COMMERCE BUREAU OF STANDARDS S. W. STRATTON, Director CIRCULAR OF THE BUREAU OF STANDARDS No. Ill [Issued, March 11, 1921] RECOMMENDED SPECIFICATION FOR FLAT INTERIOR LITHOPONE PAINT, WHITE AND LIGHT TINTS PREPARED AND RECOMMENDED BY THE U. S. INTERDEPARTMENTAL COM- MITTEE ON PAINT SPECIFICATION STANDARDIZATION, JANUARY 21, 1921. P. H. WALKER, BUREAU OF STANDARDS, CHAIRMAN; J. W. GINDER, TREAS- URY DEPARTMENT, SECRETARY [This committee was appointed at the suggestion of the Secretary of Commerce, and consisted of repre- sentatives of the War, Navy, Agriculture, Interior, Post Office, Treasury, and Commerce Departments, the Panama Canal, and the Educational Bureau of the Paint Manufacturers* Association of the United States. The committee submitted a preliminary draft of the specification to a large number of representa- tives of the paint manufacturers, and gave careful consideration to the replies received.] CONTENTS Page 1. General 1 2 . Sampling 2 3 . Laboratory examination 3 4 . Analysis of pigment 5 5 . Reagents 7 1. GENERAL This specification covers ready-mixed lithopone paints, fre- quently known as flat, washable wall paint, in white and a variety of light tints. Paints under this specification are not intended for outside exposure; they shall dry to dead flat opaque coats that will adhere well to wood, metal, and plaster, stand washing with soap and water, and show no material change in color on exposure to light. The paint shall be purchased by volume (231 cubic inches to the gallon). 34615°—21 T 2 Circular of the Bureau of Standards (a) Pigment.—The pigment shall consist of: Maximum Minimum Per cent Per cent Lithopone 80 Zinc oxide 10 Tinting and extending pigments 10 Material soluble in water 0.8 Note.— he lithopone used must contain not less than 26 per cent of zinc sulphide and must not darken on exposure.