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Package 'Ciaawconsensus'
Package ‘CIAAWconsensus’ September 19, 2018 Type Package Title Isotope Ratio Meta-Analysis Version 1.3 Author Juris Meija and Antonio Possolo Maintainer Juris Meija <[email protected]> Description Calculation of consensus values for atomic weights, isotope amount ratios, and iso- topic abundances with the associated uncertainties using multivariate meta-regression ap- proach for consensus building. License Unlimited LazyData yes Imports mvtnorm, stringr, numDeriv, stats, Matrix NeedsCompilation no Repository CRAN Date/Publication 2018-09-19 13:30:12 UTC R topics documented: abundances2ratios . .2 at.weight . .3 ciaaw.mass.2003 . .4 ciaaw.mass.2012 . .5 ciaaw.mass.2016 . .6 iridium.data . .6 mmm ............................................7 normalize.ratios . .8 platinum.data . .9 Index 10 1 2 abundances2ratios abundances2ratios Isotope ratios of a chemical element from isotopic abundances Description This function calculates the isotope ratios of a chemical element from the given isotopic abundances and their uncertainties. The uncertainty evaluation is done using the propagation of uncertainty and the missing correlations between the isotopic abundances are reconstructed using Monte Carlo methods. Usage abundances2ratios(x, ux, ref=1, iterations=1e4) Arguments x A vector of isotopic abundances of an element ux Standard uncertainties of x ref Index to specify the desired reference isotope for isotope amount ratios iterations Number of iterations for isotopic abundance correlation mapping Details Situations are often encountered where isotopic abundances are reported but not the isotope ratios. In such cases we reconstruct the isotope ratios that are consistent with the abundances and their uncertainties. Given only the abundances and their uncertainties, for elements with four or more isotopes one cannot unambiguously infer the uncertainties of the ratios due to the unknown correla- tions between isotopic abundances. -
CHEMISTRY for the Bottom of the Periodic Table
http://cyclotron.tamu.edu CHEMISTRY for the Bottom of the Periodic Table Techniques to investigate chemical properties of superheavy elements lead to improved methods for separating heavy metals THE SCIENCE The chemical properties of superheavy element 113, nihonium, are almost completely unknown, so a team of researchers from the Cyclotron Institute at Texas A&M University and the Institut Pluridisciplinaire Hubert Curien in France are developing techniques that could be used to study this fleeting element. As part of that effort, they are comparing the properties of nihonium to the chemically similar elements indium and thallium; to do so, the team studied the separation of these two elements using a new class of designer molecules called ionic liquids. THE IMPACT Measuring the chemical properties of nihonium and other superheavy elements will increase our understanding of the principles that control the Periodic Table. Comparing the data from nihonium to results for similar elements, obtained using the team’s fast, efficient, single-step process, reveals trends that arise from the structure of the Periodic Table. This research could also lead to better methods of re- using indium, a metal that is part of flat-panel displays but not currently mined in the United States. The proposed mechanism of transfer. Thallium (Tl) bonds with chlorine (Cl) and moves into the ionic liquid (in blue). SUMMARY The distribution of indium and thallium between the aque- ous and organic phases is the key to understanding the PUBLICATIONS separation of these elements. An aqueous solution, con- E.E. Tereshatov, M. Yu. Boltoeva, V. Mazan, M.F. -
Properties of Carbon the Atomic Element Carbon Has Very Diverse
Properties of Carbon The atomic element carbon has very diverse physical and chemical properties due to the nature of its bonding and atomic arrangement. fig. 1 Allotropes of Carbon Some allotropes of carbon: (a) diamond, (b) graphite, (c) lonsdaleite, (d–f) fullerenes (C60, C540, C70), (g) amorphous carbon, and (h) carbon nanotube. Carbon has several allotropes, or different forms in which it can exist. These allotropes include graphite and diamond, whose properties span a range of extremes. Despite carbon's ability to make 4 bonds and its presence in many compounds, it is highly unreactive under normal conditions. Carbon exists in 2 main isotopes: 12C and 13C. There are many other known isotopes, but they tend to be short-lived and have extremely short half-lives. Allotropes The different forms of a chemical element. Cabon is the chemical element with the symbol C and atomic number 6. As a member of group 14 on the periodic table, it is nonmetallic and tetravalent—making four electrons available to form covalent chemical bonds. Carbon has 6 protons and 6 Source URL: https://www.boundless.com/chemistry/nonmetallic-elements/carbon/properties-carbon/ Saylor URL: http://www.saylor.org/courses/chem102#6.1 Attributed to: Boundless www.saylor.org Page 1 of 2 neutrons, and has a standard atomic weight of 12.0107 amu. Its electron configuration is denoted as 1s22s22p2. It is a solid, and sublimes at 3,642 °C. It's oxidation state ranges from 4 to -4, and it has an electronegativity rating of 2.55 on the Pauling scale. Carbon has several allotropes, or different forms in which it exists. -
IUPAC Wire See Also
News and information on IUPAC, its fellows, and member organizations. IUPAC Wire See also www.iupac.org Flerovium and Livermorium Join the Future Earth: Research for Global Periodic Table Sustainability n 30 May 2012, IUPAC officially approved he International Council for Science (ICSU), of the name flerovium, with symbol Fl, for the which IUPAC is a member, announced a new Oelement of atomic number 114 and the name T10-year initiative named Future Earth to unify livermorium, with symbol Lv, for the element of atomic and scale up ICSU-sponsored global environmental- number 116. The names and symbols were proposed change research. by the collaborating team of the Joint Institute for Nuclear Research (Dubna, Russia) and the Lawrence Operational in 2013, this new ICSU initiative will Livermore National Laboratory (Livermore, California, provide a cutting-edge platform to coordinate scien- USA) to whom the priority for the discovery of these tific research to respond to the most critical social and elements was assigned last year. The IUPAC recom- environmental challenges of the 21st century at global mendations presenting these names is to appear in and regional levels. “This initiative will link global envi- the July 2012 issue of Pure and Applied Chemistry. ronmental change and fundamental human develop- ment questions,” said Diana Liverman, co-director of The name flerovium, with symbol Fl, lies within the Institute of the Environment at the University of tradition and honors the Flerov Laboratory of Nuclear Arizona and co-chair of the team Reactions in Dubna, Russia, where the element of that is designing Future Earth. -
The Histories Hidden in the Periodic Table
The Histories Hidden in the Periodic Table From poisoned monks and nuclear bombs to the “transfermium wars,” mapping the atomic world hasn’t been easy. By Neima Jahromi 6:00 A.M. As element hunters have become element makers, the periodic table’s meaning has changed. It now describes what is possible, in addition to what merely exists. Illustration by Ilya Milstein The story of the fifteenth element began in Hamburg, in 1669. The unsuccessful glassblower and alchemist Hennig Brandt was trying to find the philosopher’s stone, a mythical substance that could turn base metals into gold. Instead, he distilled something new. It was foamy and, depending on the preparation, yellow or black. He called it “cold fire,” because it glowed in the dark. Interested parties took a look; some felt that they were in the presence of a miracle. “If anyone had rubbed himself all over with it,” one observer noted, “his whole figure would have shone, as once did that of Moses when he came down from Mt. Sinai.” Robert Boyle, the father of modern chemistry, put some on his hand and noted how “mild and innocent” it seemed. Another scientist saw particles in it twinkling “like little stars.” At first, no one could figure out what the Prometheus of Hamburg had stolen. After one of Brandt’s confidants provided a hint—the main ingredient was “somewhat that belong’d to the Body of Man”—Boyle deduced that he and his peers had been smearing themselves with processed urine. As the Cambridge chemist Peter Wothers explains in his new history of the elements, “Antimony, Gold, and Jupiter’s Wolf” (Oxford), Brandt’s recipe called for a ton of urine. -
The Periodic Table of the Elements
The Periodic Table of the Elements The president of the Inorganic Chemistry Division, atomic number was the same as the number of protons Gerd Rosenblatt, recognizing that the periodic table in each element. of the elements found in the “Red Book” A problem for Mendeleev’s table was the position- (Nomenclature of Inorganic Chemistry, published in ing of the rare earth or lanthanoid* elements. These 1985) needed some updating—particularly elements elements had properties and atomic weight values above 103, including element 110 (darmstadtium)— similar to one another but that did not follow the reg- made a formal request to Norman Holden and Tyler ularities of the table. Eventually, they were placed in a Coplen to prepare an updated table. This table can be separate area below the main table. found below, on the IUPAC Web site, and as a tear-off The Danish physicist Niels Henrik David Bohr pro- on the inside back cover of this issue. posed his electronic orbital structure of the atom in 1921, which explained the problem of the rare earth by Norman Holden and Ty Coplen elements. The electrons in the outermost and the penultimate orbits are called valence electrons since generally their actions account for the valence of the he Russian chemist Dmitri Ivanovich Mendeleev element (i.e., electrons capable of taking part in the constructed his original periodic table in 1869 links between atoms). Chemical behavior of an ele- Tusing as its organizing principle his formulation ment depends on its valence electrons, so that when of the periodic law: if the chemical elements are only inner orbit electrons are changing from one ele- arranged in the ascending order of their atomic ment to another, there is not much difference in the weights, then at certain regular intervals (periods) chemical properties between the elements. -
Guidelines for the Use of Atomic Weights 5 10 11 12 DOI: ..., Received ...; Accepted
IUPAC Guidelines for the us e of atomic weights For Peer Review Only Journal: Pure and Applied Chemistry Manuscript ID PAC-REC-16-04-01 Manuscript Type: Recommendation Date Submitted by the Author: 01-Apr-2016 Complete List of Authors: van der Veen, Adriaan; VSL Meija, Juris Possolo, Antonio; National Institute of Standards and Technology Hibbert, David; University of New South Wales, School of Chemistry atomic weights, atomic-weight intervals, molecular weight, standard Keywords: atomic weight, measurement uncertainty, uncertainty propagation Author-Supplied Keywords: P.O. 13757, Research Triangle Park, NC (919) 485-8700 Page 1 of 13 IUPAC Pure Appl. Chem. 2016; aop 1 2 3 4 Sponsoring body: IUPAC Inorganic Chemistry Division Committee: see more details on page XXX. 5 IUPAC Recommendation 6 7 Adriaan M. H. van der Veen*, Juris Meija, Antonio Possolo, and D. Brynn Hibbert 8 9 Guidelines for the use of atomic weights 5 10 11 12 DOI: ..., Received ...; accepted ... 13 14 Abstract: Standard atomicFor weights Peer are widely used Review in science, yet the uncertainties Only associated with these 15 values are not well-understood. This recommendation provides guidance on the use of standard atomic 16 weights and their uncertainties. Furthermore, methods are provided for calculating standard uncertainties 17 of molecular weights of substances. Methods are also outlined to compute material-specific atomic weights 10 18 whose associated uncertainty may be smaller than the uncertainty associated with the standard atomic 19 weights. 20 21 Keywords: atomic weights; atomic-weight intervals; molecular weight; standard atomic weight; uncertainty; 22 uncertainty propagation 23 24 25 1 Introduction 15 26 27 Atomic weights provide a practical link the SI base units kilogram and mole. -
Project Note Weston Solutions, Inc
PROJECT NOTE WESTON SOLUTIONS, INC. To: Canadian Radium & Uranium Corp. Site File Date: June 5, 2014 W.O. No.: 20405.012.013.2222.00 From: Denise Breen, Weston Solutions, Inc. Subject: Determination of Significant Lead Concentrations in Sediment Samples References 1. New York State Department of Environmental Conservation. Technical Guidance for Screening Contaminated Sediments. March 1998. [45 pages] 2. U.S. Environmental Protection Agency (EPA) Office of Emergency Response. Establishing an Observed Release – Quick Reference Fact Sheet. Federal Register, Volume 55, No. 241. September 1995. [7 pages] 3. International Union of Pure and Applied Chemistry, Inorganic Chemistry Division Commission on Atomic Weights and Isotopic Abundances. Atomic Weights of Elements: Review 2000. 2003. [120 pages] WESTON personnel collected six sediment samples (including one environmental duplicate sample) from five locations along the surface water pathway of the Canadian Radium & Uranium Corp. (CRU) site in May 2014. The sediment samples were analyzed for Target Analyte List (TAL) Metals and Stable Lead Isotopes. 1. TAL Lead Interpretation: In order to quantify the significance for Lead, Thallium and Mercury the following was performed: 1. WESTON personnel tabulated all available TAL Metal data from the May 2014 Sediment Sampling event. 2. For each analyte of concern (Lead, Thallium, and Mercury), the highest background concentration was selected and then multiplied by three. This is the criteria to find the significance of site attributable release as per Hazard Ranking System guidelines. 3. One analytical lead result (2222-SD04) of 520 mg/kg (J) was qualified with an unknown bias. In accordance with US EPA document “Using Data to Document an Observed Release and Observed Contamination”, 2222-SD03 lead concentration was adjusted by dividing by the factor value for lead of 1.44 to equal 361 mg/kg. -
Quest for Superheavy Nuclei Began in the 1940S with the Syn Time It Takes for Half of the Sample to Decay
FEATURES Quest for superheavy nuclei 2 P.H. Heenen l and W Nazarewicz -4 IService de Physique Nucleaire Theorique, U.L.B.-C.P.229, B-1050 Brussels, Belgium 2Department ofPhysics, University ofTennessee, Knoxville, Tennessee 37996 3Physics Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831 4Institute ofTheoretical Physics, University ofWarsaw, ul. Ho\.za 69, PL-OO-681 Warsaw, Poland he discovery of new superheavy nuclei has brought much The superheavy elements mark the limit of nuclear mass and T excitement to the atomic and nuclear physics communities. charge; they inhabit the upper right corner of the nuclear land Hopes of finding regions of long-lived superheavy nuclei, pre scape, but the borderlines of their territory are unknown. The dicted in the early 1960s, have reemerged. Why is this search so stability ofthe superheavy elements has been a longstanding fun important and what newknowledge can it bring? damental question in nuclear science. How can they survive the Not every combination ofneutrons and protons makes a sta huge electrostatic repulsion? What are their properties? How ble nucleus. Our Earth is home to 81 stable elements, including large is the region of superheavy elements? We do not know yet slightly fewer than 300 stable nuclei. Other nuclei found in all the answers to these questions. This short article presents the nature, although bound to the emission ofprotons and neutrons, current status ofresearch in this field. are radioactive. That is, they eventually capture or emit electrons and positrons, alpha particles, or undergo spontaneous fission. Historical Background Each unstable isotope is characterized by its half-life (T1/2) - the The quest for superheavy nuclei began in the 1940s with the syn time it takes for half of the sample to decay. -
No. It's Livermorium!
in your element Uuh? No. It’s livermorium! Alpha decay into flerovium? It must be Lv, saysKat Day, as she tells us how little we know about element 116. t the end of last year, the International behaviour in polonium, which we’d expect to Union of Pure and Applied Chemistry have very similar chemistry. The most stable A(IUPAC) announced the verification class of polonium compounds are polonides, of the discoveries of four new chemical for example Na2Po (ref. 8), so in theory elements, 113, 115, 117 and 118, thus Na2Lv and its analogues should be attainable, completing period 7 of the periodic table1. though they are yet to be synthesized. Though now named2 (no doubt after having Experiments carried out in 2011 showed 3 213 212m read the Sceptical Chymist blog post ), that the hydrides BiH3 and PoH2 were 9 we shall wait until the public consultation surprisingly thermally stable . LvH2 would period is over before In Your Element visits be expected to be less stable than the much these ephemeral entities. lighter polonium hydride, but its chemical In the meantime, what do we know of investigation might be possible in the gas their close neighbour, element 116? Well, after phase, if a sufficiently stable isotope can a false start4, the element was first legitimately be found. reported in 2000 by a collaborative team Despite the considerable challenges posed following experiments at the Joint Institute for by the short-lived nature of livermorium, EMMA SOFIA KARLSSON, STOCKHOLM, SWEDEN STOCKHOLM, KARLSSON, EMMA SOFIA Nuclear Research (JINR) in Dubna, Russia. -
The Quest to Explore the Heaviest Elements Raises Questions About How Far Researchers Can Extend Mendeleev’S Creation
ON THE EDGE OF THE PERIODIC TABLE The quest to explore the heaviest elements raises questions about how far researchers can extend Mendeleev’s creation. BY PHILIP BALL 552 | NATURE | VOL 565 | 31 JANUARY 2019 ©2019 Spri nger Nature Li mited. All ri ghts reserved. ©2019 Spri nger Nature Li mited. All ri ghts reserved. FEATURE NEWS f you wanted to create the world’s next undiscovered element, num- Berkeley or at the Joint Institute for Nuclear Research (JINR) in Dubna, ber 119 in the periodic table, here’s a possible recipe. Take a few Russia — the group that Oganessian leads — it took place in an atmos- milligrams of berkelium, a rare radioactive metal that can be made phere of cold-war competition. In the 1980s, Germany joined the race; I only in specialized nuclear reactors. Bombard the sample with a beam an institute in Darmstadt now named the Helmholtz Center for Heavy of titanium ions, accelerated to around one-tenth the speed of light. Ion Research (GSI) made all the elements between 107 and 112. Keep this up for about a year, and be patient. Very patient. For every The competitive edge of earlier years has waned, says Christoph 10 quintillion (1018) titanium ions that slam into the berkelium target Düllmann, who heads the GSI’s superheavy-elements department: — roughly a year’s worth of beam time — the experiment will probably now, researchers frequently talk to each other and carry out some produce only one atom of element 119. experiments collaboratively. The credit for creating later elements On that rare occasion, a titanium and a berkelium nucleus will collide up to 118 has gone variously, and sometimes jointly, to teams from and merge, the speed of their impact overcoming their electrical repul- sion to create something never before seen on Earth, maybe even in the Universe. -
Atomic Weights of the Elements 1989
Atomic Weights of the Elements 1989 Cite as: Journal of Physical and Chemical Reference Data 20, 1313 (1991); https://doi.org/10.1063/1.555902 Submitted: 03 June 1991 . Published Online: 15 October 2009 J. R. De Laeter, and K. G. Heumann ARTICLES YOU MAY BE INTERESTED IN The Solubility of Carbon Dioxide in Water at Low Pressure Journal of Physical and Chemical Reference Data 20, 1201 (1991); https:// doi.org/10.1063/1.555900 Chemical Kinetic Data Sheets for High-Temperature Reactions. Part II Journal of Physical and Chemical Reference Data 20, 1211 (1991); https:// doi.org/10.1063/1.555901 Atomic Weights of the Elements 1991 Journal of Physical and Chemical Reference Data 22, 1571 (1993); https:// doi.org/10.1063/1.555933 Journal of Physical and Chemical Reference Data 20, 1313 (1991); https://doi.org/10.1063/1.555902 20, 1313 © 1991 American Institute of Physics for the National Institute of Standards and Technology. a Atomic Weights of the Elements 1989 ) J. R. De Laeter Curtin UlliversityofTechnology, Perth, Western Australia, 6001, Australia K. G. Heumann University ofRegensburg, Regensburg, Germany Received June 3, 1991 The biennial review of atomic weight, A r (E), determinations, and other cognate data has resulted in changes for nickel from 58.69 ± 0.01 to 58.6934 ± 0.0002 and for antimo ny from 121.75 ± 0.03 to 121.757 ± 0.003 due to new calibrated measurements. Because the measurement of the isotopic composition of mercury has also been improved during the last two years, the Commission was able to reduce the uncertainty of the atomic weight of this eJement from 200.59 ± 0.03 to 200.59 ± 0.02.