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Th Thorium Compounds with S, Se, Te and B
springer.com Chemistry : Chemistry (general) Brown, David, Wedemeyer, Horst, Buschbeck, Karl-Christian, Keller, Cornelius (Editors-in-chief.) Th Thorium Compounds with S, Se, Te and B The present volume, Thorium C5, deals with the compounds of thorium and sulfur, selenium, tellurium, and boron, as well as with oxoacid compounds of the three chalcogen elements. Thorium borates have already been treated in Thorium C2. In contrast to the corresponding compounds of uranium the thorium sulfides, etc. , do not show any nuclear or other technological application; they are only of academic interest, despite some very interest• ing electronic properties, especially of the 1 : 1 compounds. The thorium-sulfur and the thorium• boron systems in particular were studied in detail, so that we have a clear picture of them, whereas there are still a lot of open questions in the systems Th-Se and Th-Te - not very different from other metal chalcogenide systems. Thorium sulfates are of some technological importance because they are formed in solution during recovery of thorium from monazite by sulfuric acid leaching. The very detailed and critical treatment of the chemical and physical Springer properties of the compounds discussed also enables us to find gaps still remaining in our 8th ed. 1985, XIX, 149 p. knowledge and thus to initiate new research in this field. I want to thank the two authors, Dr. 8th 28 illus., 1 illus. in color. edition Horst Wedemeyer (Karlsruhe) and Dr. David Brown (Harwell), for their excellent contributions, the "Literaturabteilung" of the Karlsruhe Nuclear Research Center for its help in providing reports and other documents difficult to procure, as well as the staff of the Gmelin-Institute, especially to Dr. -
Study of Rare Earth Elements, Uranium and Thorium Migration in Rocks from Espinharas Uranium Deposit, Paraiba - Brazil
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 STUDY OF RARE EARTH ELEMENTS, URANIUM AND THORIUM MIGRATION IN ROCKS FROM ESPINHARAS URANIUM DEPOSIT, PARAIBA - BRAZIL Cirilo C.S. Conceição Instituto de Radioproteção e Dosimetria -IRD Av. salvador Allend, S/N - Jacarepaguá Rio de Janeiro, Brazil CEP.: 22780-160 [email protected] ABSTRACT The determination of Rare Earth Elements as natural analogue in patterns geologic has grown as a tool for predicting the long-term safety of nuclear disposal in geological formation. Migration of natural radionuclides is one of the most serious problems in the waste deposit from nuclear fuel cycle. Rare Earth Elements show the same kinetic behavior in rocks as natural radionuclides. This similar property of the analogues allows perform studies and models on the subject of radionuclides migration. The aim of this study was to determine the distribution of Rare Earth Elements in rocks located at Espinharas – Paraíba – Brazil, uranium deposit. In this work are presented the results from the study above the distribution of rare earth elements in function of the degree of mineralized rocks, composition and the conditions of radioactive equilibrium of the uranium and thorium in some fractures on the rocks from radioactive occurrence of Espinharas-Brazil. The results show that there is a correlation of heavy Rare Earth Elements, uranium and Thorium concentrations to oxidation factor of the rocks. However this correlation was not observed for light Rare Earth Elements. It means that heavy Rare earth Elements follow the natural radionuclides in oxidation process of rocks. -
The Development of the Periodic Table and Its Consequences Citation: J
Firenze University Press www.fupress.com/substantia The Development of the Periodic Table and its Consequences Citation: J. Emsley (2019) The Devel- opment of the Periodic Table and its Consequences. Substantia 3(2) Suppl. 5: 15-27. doi: 10.13128/Substantia-297 John Emsley Copyright: © 2019 J. Emsley. This is Alameda Lodge, 23a Alameda Road, Ampthill, MK45 2LA, UK an open access, peer-reviewed article E-mail: [email protected] published by Firenze University Press (http://www.fupress.com/substantia) and distributed under the terms of the Abstract. Chemistry is fortunate among the sciences in having an icon that is instant- Creative Commons Attribution License, ly recognisable around the world: the periodic table. The United Nations has deemed which permits unrestricted use, distri- 2019 to be the International Year of the Periodic Table, in commemoration of the 150th bution, and reproduction in any medi- anniversary of the first paper in which it appeared. That had been written by a Russian um, provided the original author and chemist, Dmitri Mendeleev, and was published in May 1869. Since then, there have source are credited. been many versions of the table, but one format has come to be the most widely used Data Availability Statement: All rel- and is to be seen everywhere. The route to this preferred form of the table makes an evant data are within the paper and its interesting story. Supporting Information files. Keywords. Periodic table, Mendeleev, Newlands, Deming, Seaborg. Competing Interests: The Author(s) declare(s) no conflict of interest. INTRODUCTION There are hundreds of periodic tables but the one that is widely repro- duced has the approval of the International Union of Pure and Applied Chemistry (IUPAC) and is shown in Fig.1. -
Lead in Your Home Portrait Color
Protect Your Family From Lead in Your Home United States Environmental Protection Agency United States Consumer Product Safety Commission United States Department of Housing and Urban Development March 2021 Are You Planning to Buy or Rent a Home Built Before 1978? Did you know that many homes built before 1978 have lead-based paint? Lead from paint, chips, and dust can pose serious health hazards. Read this entire brochure to learn: • How lead gets into the body • How lead afects health • What you can do to protect your family • Where to go for more information Before renting or buying a pre-1978 home or apartment, federal law requires: • Sellers must disclose known information on lead-based paint or lead- based paint hazards before selling a house. • Real estate sales contracts must include a specifc warning statement about lead-based paint. Buyers have up to 10 days to check for lead. • Landlords must disclose known information on lead-based paint or lead-based paint hazards before leases take efect. Leases must include a specifc warning statement about lead-based paint. If undertaking renovations, repairs, or painting (RRP) projects in your pre-1978 home or apartment: • Read EPA’s pamphlet, The Lead-Safe Certifed Guide to Renovate Right, to learn about the lead-safe work practices that contractors are required to follow when working in your home (see page 12). Simple Steps to Protect Your Family from Lead Hazards If you think your home has lead-based paint: • Don’t try to remove lead-based paint yourself. • Always keep painted surfaces in good condition to minimize deterioration. -
Of the Periodic Table
of the Periodic Table teacher notes Give your students a visual introduction to the families of the periodic table! This product includes eight mini- posters, one for each of the element families on the main group of the periodic table: Alkali Metals, Alkaline Earth Metals, Boron/Aluminum Group (Icosagens), Carbon Group (Crystallogens), Nitrogen Group (Pnictogens), Oxygen Group (Chalcogens), Halogens, and Noble Gases. The mini-posters give overview information about the family as well as a visual of where on the periodic table the family is located and a diagram of an atom of that family highlighting the number of valence electrons. Also included is the student packet, which is broken into the eight families and asks for specific information that students will find on the mini-posters. The students are also directed to color each family with a specific color on the blank graphic organizer at the end of their packet and they go to the fantastic interactive table at www.periodictable.com to learn even more about the elements in each family. Furthermore, there is a section for students to conduct their own research on the element of hydrogen, which does not belong to a family. When I use this activity, I print two of each mini-poster in color (pages 8 through 15 of this file), laminate them, and lay them on a big table. I have students work in partners to read about each family, one at a time, and complete that section of the student packet (pages 16 through 21 of this file). When they finish, they bring the mini-poster back to the table for another group to use. -
Radiological Implications of Plutonium Recycle and the Use of Thorium Fuels in Power Reactor Operations
01 RD/B/N3523 Central Electricity Generating Board Research Department Berkeley Nuclear Laboratories RADIOLOGICAL IMPLICATIONS OF PLUTONIUM RECYCLE AND THE USE OF THORIUM FUELS IN POWER REACTOR OPERATIONS By H. F. Macdonald XJ034 January 1976 DISCLAIMER Portions of this document may be illegible in electronic image products. Images are produced from the best available original document. Radiological Implications of Plutonium Recycle and the Use of Thorium Fuels in Power Reactor Operations “ by - H.F. Macdonald Approved Head of Health Physics Research Section For inclusion in Nuclear Science Abstracts SUMMARY As economically attractive sources of natural uranium are gradually depleted attention will turn to recycling plutonium or the use of thorium fuels. In this study the radiological implications of these fuel cycles in terms of fuel handling and radioactive waste disposal are investigated in 235 relation to a conventional U enriched oxide fuel. It is suggested that a comparative study of this nature may be an important aspect of the overall optimisation of future fuel cycle strategies. It is shown that the use of thorium based fuels has distinct advan tages in terms of neutron dose rates from irradiated fuels and long term a decay heating commitment compared with conventional uranium/plutonium fuels. However, this introduces a y dose rate problem in the fabrication 233 and handling of unirradiated U fuels. For both plutonium and thorium fuels these radiological problems increase during storage of the fuel prior to reactor irradiation. Finally, the novel health physics problems which arise in the handling and processing of thorium fuels are reviewed in an appendix. -
Mercury and Lead Pollution: Still a Critical Issue in Europe
06 December 2007 Mercury and Lead Pollution: still a Critical Issue in Europe Human activities release heavy metals into the atmosphere where they are also transported across national boundaries. This results in air, soil and water pollution through the deposition of heavy metals in environments that are located far away from the actual emission sources. Atmospheric deposition of mercury and lead in particular are calculated to be too high, affecting respectively 51.2% and 7.4% of EU-25 ecosystems respectively in 2000. Heavy metals such as cadmium, lead and mercury can result in serious health risks (e.g. lung damage, kidney diseases, nervous system failures, etc.) and can be harmful to the environment (e.g. soil and water pollution, accumulation in plants). In 1979, the European Union (EU) signed the Long-range Transboundary Air Pollution Convention (LRTAP1), which was the first international legally binding instrument dealing with problems of air pollution on a broad regional basis, including pollution due to heavy metals emissions. In Europe, research programs focusing on heavy metals are already in place, including the EU-funded project ESPREME 2, which aims at developing methods and identifying strategies to support EU environmental policy-making for reducing the emissions and thus the harmful impacts of heavy metals. In the framework of the LRTAP, a methodology 3 was developed to assess the critical loads of heavy metals for both terrestrial and aquatic ecosystems, as well as for human health. The critical load is a measure of how much metal input from anthropogenic sources a system can tolerate. It is the threshold below which significant harmful effects on human health and on the environment do not occur, according to present knowledge. -
The Actinide Research Quarterly Is Published Quarterly to Highlight Recent Achievements and Ongoing Programs of the Nuclear Materials Technology Division
1st quarter 2000 TheLos Actinide Alamos National Research Laboratory N u c l e a r M aQuarterly t e r i a l s R e s e a r c h a n d T e c h n o l o g y a U.S. Department of Energy Laboratory Organizers Issue an Invitation to In This Issue Plutonium Futures 1 —The Science Organizers Issue an Invitation to Plutonium Futures —The Science The second of a series of international con- have an exciting collection of some 180 invited ferences on plutonium will be held in Santa Fe, and contributed papers with topics ranging 2 NM, this summer, July 10–13. It follows the very broadly in materials science, transuranic 238Pu Aqueous highly successful 1997 conference, “Plutonium waste forms, nuclear fuels and isotopes, separa- Processing Line Will Futures - The Science,” which attracted over 300 tions, actinides in the environment, detection Provide New NMT participants representing 14 countries. The U.S. and analysis, actinide compounds and com- Capability participants, who made up about 70 percent of plexes, and condensed matter physics of ac- the total participants, came from Department of tinides. These papers, presented in separate 4 Energy national laboratories and a score of uni- oral and poster sessions, will give attendees a Editorial: versities and industries. As in 1997, the confer- chance to learn about current research outside Transactinium ence is sponsored by the Los Alamos National of their particular specialties and provide an Science Needs Laboratory in cooperation with the American opportunity for interdisciplinary discussions Educational Nuclear Society. -
Three Related Topics on the Periodic Tables of Elements
Three related topics on the periodic tables of elements Yoshiteru Maeno*, Kouichi Hagino, and Takehiko Ishiguro Department of physics, Kyoto University, Kyoto 606-8502, Japan * [email protected] (The Foundations of Chemistry: received 30 May 2020; accepted 31 July 2020) Abstaract: A large variety of periodic tables of the chemical elements have been proposed. It was Mendeleev who proposed a periodic table based on the extensive periodic law and predicted a number of unknown elements at that time. The periodic table currently used worldwide is of a long form pioneered by Werner in 1905. As the first topic, we describe the work of Pfeiffer (1920), who refined Werner’s work and rearranged the rare-earth elements in a separate table below the main table for convenience. Today’s widely used periodic table essentially inherits Pfeiffer’s arrangements. Although long-form tables more precisely represent electron orbitals around a nucleus, they lose some of the features of Mendeleev’s short-form table to express similarities of chemical properties of elements when forming compounds. As the second topic, we compare various three-dimensional helical periodic tables that resolve some of the shortcomings of the long-form periodic tables in this respect. In particular, we explain how the 3D periodic table “Elementouch” (Maeno 2001), which combines the s- and p-blocks into one tube, can recover features of Mendeleev’s periodic law. Finally we introduce a topic on the recently proposed nuclear periodic table based on the proton magic numbers (Hagino and Maeno 2020). Here, the nuclear shell structure leads to a new arrangement of the elements with the proton magic-number nuclei treated like noble-gas atoms. -
Recovery of Silver, Gold, and Lead from a Complex Sulfide Ore Using Ferric Chloride, Thiourea, and Brine Leach Solutions
PLEASE DO NOT REI10VE FROM LIBRARY iRIi9022 i Bureau of M ines Report of Investigations/1986 Recovery of Silver, Gold, and Lead From a Complex Sulfide Ore Using Ferric Chloride, Thiourea, and Brine Leach Solutions By R. G. Sandberg and J. L. Huiatt UNITED STATES DEPARTMENT OF THE INTERIOR Report of Investigations 9022 Recovery of Silver, Gold, and Lead From a Complex Sulfide Ore Using Ferric Chloride, Thiourea, and Brine Leach Solutions By R. G. Sandberg and J. L. Huiatt UNITED STATES DEPARTMENT OF THE INTERIOR Donald Paul Hodel. Secretary BUREAU OF MINES Robert C. Horton. Director Library of Congress Cataloging in Publicatiori Data: Sandberg, R. G. (Richard G.) Recovery of silver, gold, and lead from a complex sulfide ore using ferric chloride, rhiourea, and brine leach solurions. (Repon of invesrigarions / Unired Srares Deparrmenr of rhe Inrerior, Bureau of Mines; 9022) Bibliography: p. 14. Supr. of Docs. no.: I 28.23: 9022. 1. Silver-Merallurgy. 2. Gold-Merallurgy. 3. Lead-Merallurgy. 4. Leaching. 5. Ferric chloride. 6. Salr. I. Huiarl, J. L. II. Tide. III. Series: Repon of invesrigarions (Unired Srares. Bureau of Mines) ; 9022. TN23.U43 [TN770] 6228 (669'.231 1\6-600056 CONTENTS Abstract............................................................................................................... 1 Introduction. .......................................................................................................... 2 Materials.. .. .. .. .. .. .. .. .. .. .. .... .. .. ...... .. .. .. .. • .. .. .. .• .. ... .. .. .. .. .. .. . -
Lead Poisoning and Gold Mining in Nigeria's Zamfara State
A HEAVY PRICE: LEAD POISONING AND GOLD MINING IN nigeria’s ZAMFARA STATE Photographs by Marcus Bleasdale/VII for Human Rights Watch A boy in a compound in Bagega, Zamfara State, Nigeria. Many families processed ore in their compounds, crushing and grinding the rocks in their homes. Because of the lead poisoning, most families have stopped processing in their homes and the operations have been moved a short distance from the village. Some walls in these compounds are made with sediment from a nearby pond that is likely highly contaminated with lead from nearby ore processing. These walls contaminate the compound with lead over time. Since 2010 ongoing, widespread, acute lead poisoning in Zamfara state has killed at least 400 children. Considered the worst outbreak of lead poisoning in modern history, more than 3,500 affected children require urgent, life- saving treatment. Less than half are receiving it. Among adults there are high rates of infertility and miscarriage. Left: The mother of this child lost two of her four children to lead poisoning. Zamfara is a mineral-rich state, with significant deposits of gold. The acute lead poisoning in Zamfara is a result of artisanal gold mining: small scale mining done with rudimentary tools. Miners crush and grind ore to extract gold, and in the process release dust that is highly contaminated with lead. Children in affected areas are exposed to this dust when they are laboring in the processing site, when their relatives return home covered with dust on their clothes and hands, and when the processing occurs in their home. -
How to Find out If You Have a Lead Service Line (PDF)
How to Find Out if You Have a Lead Service Line Trenton Water Works (TWW) needs your help in identifying the lead and galvanized steel service lines in the city’s water system. Galvanized steel service lines may be lead lined or have goosenecks that are made of lead material. Services that contain lead materials pose known health risks. TWW is currently undergoing a Lead Service Line Replacement Program which offers limited replacement of service lines made of lead material at a highly discounted rate. If you HAVE NOT received an invitation into the Lead Service Line Program, it means that TWW’s records indicate that you DO NOT have a lead or galvanized steel service line. TWW needs your help in confirming these records. Please perform steps 1-5 listed below and send your lead service line material results, along with your address, to [email protected]. Material Verification Test What you will need: a house key or coin and a magnet. Steps to testing your water service line material: 1. Find the water meter on your property. 2. Look for the pipe that comes through the outside wall of your home and connects to your meter. 3. Use a key or coin to gently scratch the pipe (like you would scratch a lottery ticket). If the pipe is painted, use sandpaper to expose the metal first. 4. Place the magnet on the pipe to see if it sticks to the pipe. 5. Determine your pipe material and send your results and address to [email protected]. Material Verification Test To find out if you have a copper, lead or galvanized steel service on your property, you (or your landlord) can perform a material verification test on the water service line where it connects to the water meter to determine the material of the water service line on your property.