Paper FUNCTIONAL SORBENTS for SELECTIVE CAPTURE OF
Total Page:16
File Type:pdf, Size:1020Kb
Load more
Recommended publications
-
Table 2.Iii.1. Fissionable Isotopes1
FISSIONABLE ISOTOPES Charles P. Blair Last revised: 2012 “While several isotopes are theoretically fissionable, RANNSAD defines fissionable isotopes as either uranium-233 or 235; plutonium 238, 239, 240, 241, or 242, or Americium-241. See, Ackerman, Asal, Bale, Blair and Rethemeyer, Anatomizing Radiological and Nuclear Non-State Adversaries: Identifying the Adversary, p. 99-101, footnote #10, TABLE 2.III.1. FISSIONABLE ISOTOPES1 Isotope Availability Possible Fission Bare Critical Weapon-types mass2 Uranium-233 MEDIUM: DOE reportedly stores Gun-type or implosion-type 15 kg more than one metric ton of U- 233.3 Uranium-235 HIGH: As of 2007, 1700 metric Gun-type or implosion-type 50 kg tons of HEU existed globally, in both civilian and military stocks.4 Plutonium- HIGH: A separated global stock of Implosion 10 kg 238 plutonium, both civilian and military, of over 500 tons.5 Implosion 10 kg Plutonium- Produced in military and civilian 239 reactor fuels. Typically, reactor Plutonium- grade plutonium (RGP) consists Implosion 40 kg 240 of roughly 60 percent plutonium- Plutonium- 239, 25 percent plutonium-240, Implosion 10-13 kg nine percent plutonium-241, five 241 percent plutonium-242 and one Plutonium- percent plutonium-2386 (these Implosion 89 -100 kg 242 percentages are influenced by how long the fuel is irradiated in the reactor).7 1 This table is drawn, in part, from Charles P. Blair, “Jihadists and Nuclear Weapons,” in Gary A. Ackerman and Jeremy Tamsett, ed., Jihadists and Weapons of Mass Destruction: A Growing Threat (New York: Taylor and Francis, 2009), pp. 196-197. See also, David Albright N 2 “Bare critical mass” refers to the absence of an initiator or a reflector. -
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. -
Rational Ligand Design for U(VI) and Pu(IV)* by Géza Szigethy BA
Rational Ligand Design for U(VI) and Pu(IV)* by Géza Szigethy B.A. (Princeton University), 2004 A dissertation submitted in partial satisfaction of the requirements for the degree of Doctor of Philosophy in Chemistry in the Graduate Division of the University of California, Berkeley Committee in charge: Professor Kenneth N. Raymond, Chair Professor Richard A. Andersen Professor Garrison Sposito Fall 2009 * This research and the ALS are supported by the Director, Office of Science, Office of Basic Energy Sciences (OBES), and the OBES Division of Chemical Sciences, Geosciences, and Biosciences of the U.S. Department of Energy at LBNL under Contract No. DE-AC02- 05CH11231. Rational Ligand Design for U(VI) and Pu(IV) by Géza Szigethy B.A. (Princeton University), 2004 A dissertation submitted in partial satisfaction of the requirements for the degree of Doctor of Philosophy in Chemistry in the Graduate Division of the University of California, Berkeley Committee in charge: Professor Kenneth N. Raymond, Chair Professor Richard A. Andersen Professor Garrison Sposito Fall 2009 Rational Ligand Design for U(VI) and Pu(IV) Copyright © 2009 Géza Szigethy Abstract Rational Ligand Design for U(VI) and Pu(IV) by Géza Szigethy Doctor of Philosophy in Chemistry University of California, Berkeley Professor Kenneth N. Raymond, Chair Nuclear power is an attractive alternative to hydrocarbon-based energy production at a time when moving away from carbon-producing processes is widely accepted as a significant developmental need. Hence, the radioactive actinide power sources for this industry are necessarily becoming more widespread, which is accompanied by the increased risk of exposure to both biological and environmental systems. -
Procedure for Determining Uranium, Plutonium and Americium by Extraction-Chromatographic Procedures
Procedure for determining uranium, plutonium and americium by extraction-chromatographic procedures H-U/Pu/Am-AWASS-01 Authors: M. Beyermann D. Obrikat Federal coordinating office for drinking water, groundwater, wastewater, sludge, waste and wastewater of nuclear power plants (Leitstelle für die Überwachung der Radioaktivität in Trinkwasser, Grundwasser, Abwasser, Klärschlamm, Reststoffen und Abfällen) ISSN 1865-8725 Version October 2000 Procedures manual for monitoring of radioactive substances in the environment and of external radiation (Messanleitungen für die „Überwachung radioaktiver Stoffe in der Umwelt und externer Strahlung“) H-U/Pu/Am-AWASS-01-01 Procedure for determining uranium, plutonium and americium by means of extraction- chromatographic procedures 1 Scope This procedure serves to simultaneously determine the uranium isotopes U-234, U-235 and U-238, the plutonium isotopes Pu-238, Pu-239 and Pu-240, as well as the americium isotope Am-241 in samples of wastewater from nuclear facilities. It furthermore offers an option of determining the curium isotopes Cm-242 and Cm-244 without further effort. For determining Pu-241, reference is made to pro- cedure H-Pu-241-AWASS-01 of these measuring instructions. 2 Sampling As far as sampling is concerned, reference is made to procedure H-SPEKT- AWASS-01 of these measuring instructions. The sample of the wastewater to be analysed is acidified with ca. 10 ml of concentrated nitric acid (14 mol·l-1) per litre to a pH of about 1. The stability of the acidic reaction needs to be monitored, in particular if the sample is stored for an extended period of time. This procedure ensures that a detection limit of 0,05 Bq·l-1 for alpha-emitters is reached in a sample volume of 0,1 litres to 0,25 litres and thus complies with the nuclear safety standard 1504 of the Nuclear Safety Standards Commission (1). -
Americium, Neptunium, Plutonium, Thorium, Curium, and Uranium in Water
Analytical Procedure AMERICIUM, NEPTUNIUM, PLUTONIUM, THORIUM, CURIUM, AND URANIUM IN WATER (WITH VACUUM BOX SYSTEM) 1. SCOPE 1.1. This is a method for the separation of americium, neptunium, plutonium, thorium, curium and uranium in water. After completing this method, source preparation for measurement of actinides by alpha spectrometry is performed by electrolytic deposition onto stainless steel planchets (Eichrom Method SPA02) or by rare earth fluoride microprecipitation onto polypropylene filters (Eichrom Method SPA01). 1.2. This method does not address all aspects of safety, quality control, calibration or instrument set-up. However, enough detail is given for a trained radiochemist to achieve accurate and precise results for the analysis of the analyte(s) from the appropriate matrix, when incorporating the appropriate agency or laboratory safety, quality and laboratory control standards. 2. SUMMARY OF METHOD 2.1. Up to 1 liter of water sample is acidified to pH 2 and actinides are co-precipitated by calcium phosphate. 2.2. Tetravalent actinides (Pu, Th, Np) are retained on TEVA Resin and other actinides (U, Am) are retained on TRU Resin. 3. SIGNIFICANCE OF USE 3.1. This method allows for the isotopic analysis of six actinides from a single sample. The use of vacuum assisted flow and stacked cartridges enable completion of sample preparation for batches of 12-24 samples in as little as ten hours. Eichrom Technologies, LLC Method No: ACW16VBS Analytical Procedure Revision: 1.1 May 1, 2014 Page 1 of 1 4 4. INTERFERENCES 4.1. Nuclides with unresolvable alpha energies such as 241Am and 238Pu, 237Np and 234U, or 232U and 210Po must be chemically separated to enable measurement. -
Periodic Table 1 Periodic Table
Periodic table 1 Periodic table This article is about the table used in chemistry. For other uses, see Periodic table (disambiguation). The periodic table is a tabular arrangement of the chemical elements, organized on the basis of their atomic numbers (numbers of protons in the nucleus), electron configurations , and recurring chemical properties. Elements are presented in order of increasing atomic number, which is typically listed with the chemical symbol in each box. The standard form of the table consists of a grid of elements laid out in 18 columns and 7 Standard 18-column form of the periodic table. For the color legend, see section Layout, rows, with a double row of elements under the larger table. below that. The table can also be deconstructed into four rectangular blocks: the s-block to the left, the p-block to the right, the d-block in the middle, and the f-block below that. The rows of the table are called periods; the columns are called groups, with some of these having names such as halogens or noble gases. Since, by definition, a periodic table incorporates recurring trends, any such table can be used to derive relationships between the properties of the elements and predict the properties of new, yet to be discovered or synthesized, elements. As a result, a periodic table—whether in the standard form or some other variant—provides a useful framework for analyzing chemical behavior, and such tables are widely used in chemistry and other sciences. Although precursors exist, Dmitri Mendeleev is generally credited with the publication, in 1869, of the first widely recognized periodic table. -
Structural Analysis and Separation of Lanthanides With
Full Paper Chemistry—A European Journal doi.org/10.1002/chem.202002653 & CoordinationChemistry The Earlier the Better:Structural Analysis and Separation of Lanthanides with Pyrroloquinoline Quinone HenningLumpe+,[a] Annika Menke+,[a] Christoph Haisch,[b] Peter Mayer,[a] Anke Kabelitz,[c] Kirill V. Yusenko,[c] Ana Guilherme Buzanich,[c] Theresa Block,[d] Rainer Pçttgen,[d] Franziska Emmerling,[c] and Lena J. Daumann*[a] Abstract: Lanthanides (Ln) are critical raw materials,howev- ronment.The complex crystallizes as an inversion symmetric er,their mining and purification have aconsiderable nega- dimer,Eu2PQQ2,with binding of Eu in the biologically rele- tive environmental impact andsustainable recycling and vant pocket of PQQ. LnPQQ and Ln1Ln2PQQ complexes separation strategies for these elements are needed. In this were characterized by using inductively coupled plasma study,the precipitationand solubility behavior of Ln com- mass spectrometry (ICP-MS), infrared (IR) spectroscopy, 151Eu- plexes with pyrroloquinoline quinone (PQQ), the cofactor of Mçssbauer spectroscopy,X-ray total scattering, andextend- recently discovered lanthanide (Ln) dependent methanol de- ed X-ray absorption fine structure (EXAFS). It is shown that a hydrogenase (MDH)enzymes, is presented. In this context, natural enzymatic cofactor is capable to achieveseparation the molecular structure of abiorelevant europium PQQ com- by precipitationofthe notoriously similar,and thusdifficult plex was for the first time elucidated outsideaprotein envi- to separate, lanthanides to some extent. Introduction also called “vitamins, or seeds of technology” and the global demand of rare earth oxides is growing steadily.[1] Unlike their Rare earth elements (REE) include the elements 21Sc, 39Yand name suggests, REE are not particularly rare and the occur- 57La, in addition to the 14 lanthanides (Ln) from 58Ce to 71Lu. -
Americium Cas #7440-35-9
AMERICIUM CAS #7440-35-9 Division of Toxicology ToxFAQsTM April 2004 This fact sheet answers the most frequently asked health questions (FAQs) about americium. For more information, call the ATSDR Information Center at 1-888-422-8737. This fact sheet is one in a series of summaries about hazardous substances and their health effects. It is important you understand this information because this substance may harm you. The effects of exposure to any hazardous substance depend on the dose, the duration, how you are exposed, personal traits and habits, and whether other chemicals are present. HIGHLIGHTS: Very low levels of americium occur in air, water, soil, and food, as well as in smoke detectors. Exposure to radioactive americium may result in increased cancer risk. Americium has been found in at least 8 of the 1,636 National Priorities List (NPL) sites identified by the Environmental Protection Agency (EPA). What is americium? ‘ Americium strongly sticks to soil particles and does not travel very far into the ground. Americium is a man-made radioactive chemical. Americium ‘ Plants may take up small amounts of americium from the has no naturally occurring or stable isotopes. Two soil. important isotopes of americium are americium 241 (241Am) ‘ Fish may take up americium, but little builds up in the (read as americium two-forty-one) and 243Am. Both isotopes fleshy tissue. In shellfish, americium is attached to the shell have the same chemical behavior in the environment and the and not to the parts you normally eat. same chemical effects on your body. How might I be exposed to americium? 241Americium is used in ionization smoke detectors. -
Peaceful Berkelium
in your element Peaceful berkelium The first new element produced after the Second World War has led a rather peaceful life since entering the period table — until it became the target of those producing superheavy elements, as Andreas Trabesinger describes. f nomenclature were transitive, element 97 with the finding that in Bk(iii) compounds would be named after an Irish bishop spin–orbit coupling leads to a mixing of the Iwhose philosophical belief was that first excited state and the ground state. This material things do not exist. But between gives rise to unexpected electronic properties the immaterialist George Berkeley and the not present in analogous lanthanide element berkelium stands, of course, the structures containing terbium. Even more fine Californian city of Berkeley (pictured), recently5, a combined experimental and where the element was first produced in computational study revealed that berkelium December 1949. The city became the eponym can have stabilized +iii and +iV oxidation of element 97 “in a manner similar to that states also under mild aqueous conditions, used in naming its chemical homologue indicating a path to separating it from other terbium […] whose name was derived from lanthanides and actinides. the town of Ytterby, Sweden, where the rare The main use of berkelium, however — earth minerals were first found”1. arguably one that wouldn’t have met with A great honour for the city? The mayor Bishop Berkeley’s approval — remains a of Berkeley at the time reportedly displayed PHOTO STOCK / ALAMY AF ARCHIVE distinctly material one: as the target for “a complete lack of interest when he was the synthesis of other transuranium and called with the glad tidings”2. -
Americium, Neptunium, Plutonium, Thorium, Curium, and Uranium in Water
Analytical AMERICIUM, NEPTUNIUM, PLUTONIUM, THORIUM, CURIUM, AND URANIUM IN WATER (WITH VACUUM BOX SYSTEM) 1. SCOPE This is a method for the separation of americium, neptunium, plutonium, thorium, curium and uranium in water. After completing this method, source preparation for measurement of actinides by alpha spectrometry is performed by electrolytic deposition onto stainless steel planchets (Eichrom Method SPA02) or by rare earth fluoride microprecipitation onto polypropylene filters (Eichrom Method SPA01). This method does not address all aspects of safety, quality control, calibration or instrument set-up. However, enough detail is given for a trained radiochemist to achieve accurate and precise results for the analysis of the analyte(s) from the appropriate matrix, when incorporating the appropriate agency or laboratory safety, quality and laboratory control standards. 2. SUMMARY OF METHOD Up to 1 liter of water sample is acidified to pH 2 and actinides are co-precipitated by calcium phosphate. Tetravalent actinides (Pu, Th, Np) are retained on TEVA Resin and other actinides (U, Am) are retained on TRU Resin. 3. SIGNIFICANCE OF USE This method allows for the isotopic analysis of six actinides from a single sample. The use of vacuum assisted flow and stacked cartridges enable completion of sample preparation for batches of 12-24 samples in as little as ten hours. Eichrom Technologies, LLC Method No: ACW16VBS Analytical Procedure Revision: 1.2 January 24, 2019 Page 1of 14 4. INTERFERENCES Nuclides with unresolvable alpha energies such as 241Am and 238Pu, 237Np and 234U, or 232U and 210Po must be chemically separated to enable measurement. This method separates these isotopes effectively. -
3 Families of Elements
Name Class Date CHAPTER 5 The Periodic Table SECTION 3 Families of Elements KEY IDEAS As you read this section, keep these questions in mind: • What makes up a family of elements? • What properties do the elements in a group share? • Why does carbon form so many compounds? What Are Element Families? Recall that all elements can be classified into three READING TOOLBOX categories: metals, nonmetals, and semiconductors. Organize As you read Scientists classify the elements further into five families. this section, create a chart The atoms of all elements in most families have the same comparing the different number of valence electrons. Thus, members of a family families of elements. Include examples of each family in the periodic table share some properties. and describe the common properties of elements in the Group number Number of valence Name of family family. electrons Group 1 1 Alkali metals Group 2 2 Alkaline-earth metals READING CHECK Groups 3–12 varied Transition metals 1. Identify In general, what Group 17 7 Halogens do all elements in the same family have in common? Group 18 8 (except helium, Noble gases which has 2) What Are the Families of Metals? Many elements are classified as metals. Recall that metals can conduct heat and electricity. Most metals can be stretched and shaped into flat sheets or pulled into wires. Families of metals include the alkali metals, the alkaline-earth metals, and the transition metals. THE ALKALI METALS READING CHECK The elements in Group 1 form a family called the 2. Explain Why are alkali alkali metals. -
Fact Sheet: Epa Facts About Americium-241
EPA Facts About Americium-241 July 2002 What is americium-241? How are people exposed to americium-241? Americium is a man-made radioactive metal that exists Americium has been released to the environment primarily as a solid under normal conditions. Americium is by atmospheric testing of nuclear weapons. produced when plutonium absorbs neutrons in nuclear Concentrations of americium introduced into the reactors and nuclear weapons tests. environment through nuclear weapons production operations have been negligible compared with those Americium occurs in several forms called isotopes. released during atmospheric testing of nuclear explosives. The most common isotope is americium-241. Weapon sites and industries that manufacture smoke detectors are potential sources of exposure from americium-241. Potential pathways of exposure include What are the uses of americium-241? ingestion, inhalation, and the external pathway from gamma radiation. Americium when blended with beryllium is used as a neutron source in the testing of machinery and in How does americium-241 get into the body? thickness gauges in the glass industry. Americium also is used as a radiation source in medical diagnostic devices Americium can enter the body when it is inhaled or and in research. It is commonly used in minute amounts swallowed. When inhaled, the amount of americium that in smoke detectors as an ionization source. remains in the lungs depends upon the particle size and the chemical form of the americium compound. The How does americium-241 change in the chemical forms that dissolve easily may be absorbed environment? through the lung and pass into the blood stream. The forms that dissolve less easily are typically swallowed Americium-241 is formed in the environment by the decay where some may pass into the blood stream and the of plutonium contamination from nuclear weapons remainder will pass through the feces.