Some Basic Concepts
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IR-3 Elements and Groups of Elements (March 04)
1 IR-3 Elements and Groups of Elements (March 04) CONTENTS IR-3.1 Names and symbols of atoms IR-3.1.1 Systematic nomenclature and symbols for new elements IR-3.2 Indication of mass, charge and atomic number using indexes (subscripts and superscripts) IR-3.3 Isotopes IR-3.3.1 Isotopes of an element IR-3.3.2 Isotopes of hydrogen IR-3.4 Elements (or elementary substances) IR-3.4.1 Name of an element of infinite or indefinite molecular formula or structure IR-3.4.2 Name of allotropes of definite molecular formula IR-3.5 Allotropic modifications IR-3.5.1 Allotropes IR-3.5.2 Allotropic modifications constituted of discrete molecules IR-3.5.3 Crystalline allotropic modifications of an element IR-3.5.4 Solid amorphous modifications and commonly recognized allotropes of indefinite structure IR-3.6 Groups of elements IR-3.6.1 Groups of elements in the Periodic Table and their subdivisions IR-3.6.2 Collective names of groups of like elements IR-3.7 References IR-3.1 NAMES AND SYMBOLS OF ATOMS The origins of the names of some chemical elements, for example antimony, are lost in antiquity. Other elements recognised (or discovered) during the past three centuries were named according to various associations of origin, physical or chemical properties, etc., and more recently to commemorate the names of eminent scientists. In the past, some elements were given two names because two groups claimed to have discovered them. To avoid such confusion it was decided in 1947 that after the existence of a new element had been proved beyond reasonable doubt, discoverers had the right to IUPACsuggest a nameProvisional to IUPAC, but that only Recommendations the Commission on Nomenclature of Inorganic Chemistry (CNIC) could make a recommendation to the IUPAC Council to make the final Page 1 of 9 DRAFT 2 April 2004 2 decision. -
Those Two Isotopes Are Chemical Identical and Can Only Be Separated by Using Their Relatively Small Difference in Mass
Exercise2. Why is it extremely difficult to separate the two isotopes of copper, 63Cu and 65Cu? Those two isotopes are chemical identical and can only be separated by using their relatively small difference in mass. Exercise 3. If a nuclear reaction adds an extra neutron to the nucleus of 57Fe (a stable isotope of iron), it produces 58Fe (another stable isotope of iron). Will this change in the nucleus affect the number and arrangement of the electrons in the atom that’s built around this nucleus? Why or why not? No: the number of electrons = number of protons (= atomic number) and this hasn’t changed. Because the number of electrons doesn’t change and the charge in the nucleus doesn’t change, the arrangement of electron orbitals (standing waves) also doesn’t change. Exercise 4: If a nuclear reaction adds an extra proton to the nucleus of 58Fe (a stable isotope of iron), it produces 59Co (a stable isotope of cobalt). Will this change in the nucleus affect the number and arrangement of the electrons in the atom that’s built around this nucleus? Why or why not? Yes: since the nuclear charge has increased, an additional electron is needed to form a neutral atom. Because of both the change in number of electrons and the stronger Coulomb attraction from the nucleus, the arrangement of electron orbitals will change. Exercise 7. When a large nucleus is split in half during an experiment at a nuclear physics lab, the result is usually two medium-size nuclei with too many neutrons to be stable. -
Mixtures Comment on What You Observe in This Photograph
Elements Compounds Mixtures Comment on what you observe in this photograph. How do the sweets in this photograph model the idea of elements, compounds and mixtures? Elements, Compounds & Mixtures By the end of this topic students should be able to… • Identify elements, compounds and mixtures. • Define and explain the terms element, compound and mixture. • Give examples of elements, compounds and mixtures. • Describe the similarities and differences between elements, compounds and mixtures. Elements, Compounds & Mixtures How can I classify the different materials in the world around me? Elements, Compounds & Mixtures Elements, Compounds & Mixtures Elements, Compounds & Mixtures Elements, Compounds & Mixtures Elements, Compounds & Mixtures Elements, Compounds & Mixtures • What other classification systems do scientists use? • One example is the classification of plants and animals in biology. Elements, Compounds & Mixtures Could I have a brief introduction to elements, compounds and mixtures? Elements, Compounds & Mixtures • Iron and sulfur are both chemical elements. • A mixture of iron and sulfur can be separated by a magnet because iron can be magnetised but sulfur cannot. Elements, Compounds & Mixtures Duration 10 seconds. Duration • Iron and sulfur are both chemical elements. • A mixture of iron and sulfur can be separated by a magnet because iron can be magnetised but sulfur cannot. Elements, Compounds & Mixtures • Iron and sulfur react to form the compound iron(II) sulfide. • The compound iron(II) sulfide has new properties that are different to those of iron and sulfur, e.g. iron(II) sulfide is not attracted towards a magnet. Elements, Compounds & Mixtures Duration Duration 25 seconds. • Iron and sulfur react to form the compound iron(II) sulfide. -
Cross Calibration for Using Neutron Activation Analysis with Copper Samples to Measure D-T Fusion Yields
Cross Calibration for using Neutron Activation Analysis with Copper Samples to measure D-T Fusion Yields Chad A. McCoy May 5, 2011 The University of New Mexico Department of Physics and Astronomy Undergraduate Honors Thesis Advisor: Gary W. Cooper (UNM ChNE) Daniel Finley Abstract We used a dense plasma focus with maximum neutron yield greater than 1012 neutrons per pulse as a D-T neutron source to irradiate samples of copper, praseodymium, silver, and lead, to cross- calibrate the coincidence system for using neutron activation analysis to measure total neutron yields. In doing so, we counted the lead samples using an attached plastic scintillator, due to the short half-life and single gamma decay. The copper samples were counted using two 6” NaI coincidence systems and a 3” NaI coincidence system to determine the total neutron yield. For the copper samples, we used a calibration method which we refer to as the “F factor” to calibrate the system as a whole and used this factor to determine the total neutron yield. We concluded that the most accurate measurement of the D-T fusion neutron yield using copper activation detectors is by using 3 inch diameter copper samples in a 6” NaI coincidence system. This measurement gave the most accurate results relative to the lead probe and reference samples for all the copper samples tested. Furthermore, we found that the total neutron yield as measured with the 3 inch diameter copper samples in the 6” diameter NaI systems is approximately 89 ± 10 % the total neutron yield as measured using the lead, praseodymium and silver detectors. -
Radioactive Isotopes of Copper 578 (1936)
1110 NATURE jUNE 26, 1937 axis, no water is being frozen or melted with change 10h.l,5.8• Madsen has directed attention to the in temperature. When the curve is vertical with confusion over these periods and gives the half-life respect to the temperature axis, pure water is being period of the copper obtained from zinc as 17h!. frozen or melted. When the curve is inclined to the Leo Szilard, of the Clarendon Laboratory, Oxford, temperature axis, ice is being separated from or informed us that the decay curve of the copper melted into a solution, as in the concentration or bombarded by fast neutrons from radon-beryllium dilution of a sugar solution. This latter effect may contained a period of a few hours which was absent also be brought about by capillary forces or by col when slow neutrons were used, or if the radioactive loidal substances the avidity of which for water copper was obtained from zinc by fast neutron varies with their concentration. bombardment. It was arranged with him that Fig. 3 shows the results obtained upon freezing further investigations and chemical separation should fresh green peas using time as a variable instead of be made in this laboratory. temperature. 19 gm. of green peas at room tempera We irradiated 2 gm. mols of pure cupric oxide with ture were placed in the condenser and immersed in a fast neutrons from a 200 me. radium-beryllium thermostat held at -16° C. At the time of immersion source. After irradiation, we dissolved the oxide, and at intervals thereafter capacitance measurements added 500 mgm. -
Impact-Ionization Mass Spectrometry of Cosmic Dust
IMPACT-IONIZATION MASS SPECTROMETRY OF COSMIC DUST Thesis by Daniel E. Austin Submitted in Partial Fulfillment of the Requirements for the Degree of Doctor of Philosophy California Institute of Technology Pasadena, California 2003 (Defended November 5, 2002) ii © 2003 Daniel E. Austin All Rights Reserved iii Acknowledgements First of all, I thank Dave Dearden, Professor of Chemistry at Brigham Young University, and a former Caltech graduate student, for encouraging me to pursue graduate work at Caltech. The experiences I gained working with him, both as a research assistant and as a teaching assistant, proved invaluable during my stay here. Numerous people at Caltech have contributed in some way to my research efforts. Foremost among these is my advisor, Jack Beauchamp, who successfully balances providing advice and supervision with the hands-off approach that is essential to developing creativity, resourcefulness, and drive in students. I also thank all the other Beauchamp group members who have helped me in so many ways: Dmitri Kossakovski, Sang-Won Lee, Jim Smith, Heather Cox, Ron Grimm, Ryan Julian, and Rob Hodyss. I joined Jack’s group in part because of the very high caliber of students at that time. It seems I am leaving a group equally outstanding. There could be no finer collection of colleagues than this. Minta Akin, an undergraduate Caltech student, has helped tremendously with the ice accelerator, and I thank her for all her work. Mike Roy, Guy Duremberg, and Ray Garcia, the chemistry department machinists, have been both helpful and patient with me as I’ve built numerous instrument parts. -
Copper Isotope Fractionation During Surface Adsorption And
University of Texas at El Paso DigitalCommons@UTEP Open Access Theses & Dissertations 2010-01-01 Copper Isotope Fractionation During Surface Adsorption And Intracellular Incorporation By Bacteria Jesica Urbina Navarrete University of Texas at El Paso, [email protected] Follow this and additional works at: https://digitalcommons.utep.edu/open_etd Part of the Biogeochemistry Commons, Geochemistry Commons, and the Microbiology Commons Recommended Citation Navarrete, Jesica Urbina, "Copper Isotope Fractionation During Surface Adsorption And Intracellular Incorporation By Bacteria" (2010). Open Access Theses & Dissertations. 2553. https://digitalcommons.utep.edu/open_etd/2553 This is brought to you for free and open access by DigitalCommons@UTEP. It has been accepted for inclusion in Open Access Theses & Dissertations by an authorized administrator of DigitalCommons@UTEP. For more information, please contact [email protected]. COPPER ISOTOPE FRACTIONATION DURING SURFACE ADSORPTION AND INTRACELLULAR INCORPORATION BY BACTERIA JESICA URBINA NAVARRETE Environmental Science Program APPROVED: David Borrok, Ph.D., Chair Jasper G. Konter, Ph.D. Joanne T. Ellzey, Ph.D. Patricia D. Witherspoon, Ph.D. Dean of the Graduate School Copyright by Jesica Urbina Navarrete 2010 COPPER ISOTOPE FRACTIONATION DURING SURFACE ADSORPTION AND INTRACELLULAR INCORPORATION BY BACTERIA by JESICA URBINA NAVARRETE, B.S. THESIS Presented to the Faculty of the Graduate School of The University of Texas at El Paso in Partial Fulfillment of the Requirements for the Degree of MASTER OF SCIENCE Department of Environmental Science THE UNIVERSITY OF TEXAS AT EL PASO August 2010 Acknowledgements This publication was made possible through funding by the National Science Foundation (NSF) grant 0745345, the Center for Earth and Environmental Isotope Research (NSF MRI grant 0820986) and by grant number 2G12RR008124-16A1 from the National Center for Research Resources (NCRR), a component of the National Institutes of Health (NIH). -
Natural Variations of Copper and Sulfur Stable Isotopes in Blood of Hepatocellular Carcinoma Patients
Natural variations of copper and sulfur stable isotopes in blood of hepatocellular carcinoma patients Vincent Baltera,1, Andre Nogueira da Costab, Victor Paky Bondanesea, Klervia Jaouenc, Aline Lambouxa, Suleeporn Sangrajrangd, Nicolas Vincenta, François Fourela, Philippe Télouka, Michelle Gigoue, Christophe Lécuyera,f, Petcharin Srivatanakuld, Christian Bréchote,g, Francis Albarèdea, and Pierre Hainauth,i aUMR 5276, Laboratoire de Géologie de Lyon, École Normale Supérieure de Lyon, CNRS, Université de Lyon 1, BP 7000 Lyon, France; bMechanistic Toxicology & Molecular Pathology Department of Non-Clinical Development, UCB BioPharma, SPRL Chemin du Foriest 1, B-1420 Braine L’Alleud, Belgium; cDepartment of Human Evolution, Max Planck Institute for Evolutionary Anthropology, 04103 Leipzig, Germany; dNational Cancer Institute, Bangkok 10400, Thailand; eUnité 785, Pathogénèse et Traitement de l’Hépatite Fulminante et du Cancer du Foie, INSERM, Université Paris-Sud, 94800 Villejuif, France; fInstitut Universitaire de France, 75005 Paris, France; gInstitut Pasteur, 75015 Paris, France; hUnité 823, Ontogenèse et Oncogenèse Moléculaire, Institut Albert Bonniot, INSERM, Université Joseph Fourier, 38706 Grenoble, France; and iStrathclyde Institute of Global Public Health, International Prevention Research Institute, 69006 Lyon, France Edited by Thure E. Cerling, University of Utah, Salt Lake City, UT, and approved December 22, 2014 (received for review August 7, 2014) The widespread hypoxic conditions of the tumor microenviron- and sulfide (5). Regardless of the element, differences in co- ment can impair the metabolism of bioessential elements such as ordination and redox states are generally associated with isotopic copper and sulfur, notably by changing their redox state and, as effects known as isotopic fractionation. In animal models, the a consequence, their ability to bind specific molecules. -
Photoionization of Kcs Molecule: Origin of the Structured Continuum?
atoms Article Photoionization of KCs Molecule: Origin of the Structured Continuum? Goran Pichler 1,*, Robert Beuc 1, Jahja Kokaj 2, David Sarkisyan 3, Nimmy Jose 2 and Joseph Mathew 2 1 Institute of Physics, 10000 Zagreb, Croatia; [email protected] 2 Department of Physics, Kuwait University, P.O. Box 5969, Safat 13060, Kuwait; [email protected] (J.K.); [email protected] (N.J.); [email protected] (J.M.) 3 Institute for Physical Research, Armenian Academy of Science, Ashtarak 0203, Armenia; [email protected] * Correspondence: [email protected]; Tel.: +385-91-469-8826 Received: 30 April 2020; Accepted: 26 May 2020; Published: 28 May 2020 Abstract: We report the experimental observation of photoionization bands of the KCs molecule in the deep ultraviolet spectral region between 200 and 420 nm. We discuss the origin of observed photoionization bands as stemming from the absorption from the ground state of the KCs molecule to the excited states of KCs+ molecule for which we used existing potential curves of the KCs+ molecule. An alternative explanation relies on the absorption from the ground state of the KCs molecule to the doubly excited states of the KCs** molecule, situated above the lowest molecular state of KCs+. The relevant potential curves of KCs** are not known yet, but all those KCs** potential curves are certainly autoionizing. However, these two photoionization pathways may interfere resulting in a special interference structured continuum, which is observed as complex bands. Keywords: photoionization; alkali molecule; autoionization of molecule; heteronuclear molecule 1. Introduction High-temperature alkali mixtures possessing high densities of constituents enable observation of the characteristic bands of mixed alkali molecules [1]. -
Endf-201 Enof/B-Vi Summary Documentation
BNL-NCS—1754Z DE92 010079 ENDF-201 ENOF/B-VI SUMMARY DOCUMENTATION Compiled and Edited by P.F. Rose Brookhaven National Laboratory October 1991 NATIONAL NUCLEAR DATA CENTER BROOKHAVEN NATIONAL LABORATORY ASSOCIATED UNIVERSITIES, INC. UPTON, LONG ISLAND, NEW YORK 11973 ft UNDER CONTRACT NO. DE-AC02-76CH00016 WITH THE UNITED STATES DEPARTMENT OF ENERGY »'•'—••-.-*>„.,, DISCLAIMER This report was prepared as an account of work sponsored by an agency of the United States Government. Neither the United States Government nor any agency thereof, nor any of their employees, nor any of their contractors, subcontractors, or their employees, makes any warranty, express or implied, or assumes any legal liability or responsibility for the accuracy, completeness, or usefulness of any information, apparatus, product, or process disclosed, or represents that its use would not infringe privately owned rights. Reference herein to any specific commercial product, process, or service by trade name, trademark, manufacturer, or otherwise, does not necessarily constitute or imply its endorsement, recommendation, or favoring by the United States Government or any agency, contractor or subcontractor thereof. The views and opinions of authors expressed herein do not necessarily state or reflect those of the United States Government or any agency, contractor or subcontractor thereof. Printed in the United States of America Available from National Technical Information Service U.S. Department of Commerce 5285 Port Royal Road Springfield, VA 22161 NTIS price codes: -
Sulfur Oxygenase Reductases - a Structural and Biochemical Perspective
Sulfur Oxygenase Reductases - A Structural and Biochemical Perspective vom Fachbereich Biologie der Technischen Universität Darmstadt zur Erlangung des akademischen Grades eines Doctor rerum naturalium genehmigte Dissertation vorgelegt von Dipl. Biol. Andreas Veith aus Seeheim-Jugenheim 1. Referent: Dr. habil. Arnulf Kletzin 2. Referent: Prof. Dr. Felicitas Pfeifer Eingereicht am 21.07.2011 Tag der mündlichen Prüfung: 16.09.2011 Darmstadt 2011 D 17 "Trying to determine the structure of a protein by UV spectroscopy was like trying to determine the structure of a piano by listening to the sound it made while being dropped down a flight of stairs." -- Francis Crick Die vorliegende Arbeit wurde als Promotionsarbeit am Institut für Mikrobiologie und Genetik des Fachbereichs Biologie der Technischen Universität Darmstadt unter Leitung von Herrn Dr. Arnulf Kletzin in der Abteilung von Frau Prof. Felicitas Pfeifer im Zeitraum von Mai 2007 bis Juli 2011 angefertigt. Ein Teil der vorliegenden Arbeit wurde in Portugal am Instituto de Tecnologia Químicia e Biológica, Universidade Nova de Lisboa (ITQB/UNL), Oeiras, Portugal in der Arbeitsgruppe von Dr. Carlos Frazão, Dr. Cláudio M. Gomes und Prof. Miguel Teixeira im Rahmen einer Kooperation durchgeführt. Ehrenwörtliche Erklärung Ich erkläre hiermit ehrenwörtlich, dass ich die vorliegende Arbeit selbstständig angefertigt habe. Sämtliche aus fremden Quellen direkt oder indirekt übernommenen Gedanken sind als solche kenntlich gemacht. Die Arbeit wurde bisher keiner anderen Prüfungsbehörde vorgelegt und noch nicht veröffentlicht. Darmstadt, den 21.07.2011 Andreas Veith Acknowledgements First and foremost I would like to thank my supervisor Dr. Arnulf Kletzin for giving me the opportunity to step into the fascinating world of proteins. -
Carbon Monoxide Interacting with Free-Electron-Laser Pulses
Carbon monoxide interacting with free-electron-laser pulses H. I. B. Banks Department of Physics and Astronomy, University College London, Gower Street, London WC1E 6BT, United Kingdom A. Hadjipittas Department of Physics and Astronomy, University College London, Gower Street, London WC1E 6BT, United Kingdom A. Emmanouilidou Department of Physics and Astronomy, University College London, Gower Street, London WC1E 6BT, United Kingdom Abstract. We study the interaction of a heteronuclear diatomic molecule, carbon monoxide, with a free-electron laser (FEL) pulse. We compute the ion yields and the intermediate states by which the ion yields are populated. We do so using rate equations, computing all relevant molecular and atomic photoionisation cross-sections and Auger rates. We find that the charge distribution of the carbon and oxygen ion yields differ. By varying the photon energy, we demonstrate how to control higher- charged states being populated mostly by carbon or oxygen. Moreover, we identify the differences in the resulting ion yields and pathways populating these yields between a homonuclear molecule, molecular nitrogen, and a heteronuclear molecule, carbon monoxide, interacting with an FEL pulse. These two molecules have similar electronic structure. We also identify the proportion of each ion yield which accesses a two-site double-core-hole state and tailor pulse parameters to maximise this proportion. PACS numbers: 33.80.Rv, 34.80.Gs, 42.50.Hz arXiv:2004.11641v1 [physics.atom-ph] 24 Apr 2020 Submitted to: J. Phys. B: At. Mol. Opt. Phys. Carbon monoxide interacting with free-electron-laser pulses 2 1. Introduction X-ray free-electron lasers (XFELs) [1{3] have introduced new tools and techniques for the investigation and imaging of atoms and molecules [4, 5].