Francis W. Aston
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Chemistry: the Molecular Nature of Matter and Change
REVISED CONFIRMING PAGES The Components of Matter 2.1 Elements, Compounds, and 2.5 The Atomic Theory Today 2.8 Formula, Name, and Mass of Mixtures: An Atomic Overview Structure of the Atom a Compound 2.2 The Observations That Led to Atomic Number, Mass Number, and Binary Ionic Compounds an Atomic View of Matter Atomic Symbol Compounds That Contain Polyatomic Mass Conservation Isotopes Ions Definite Composition Atomic Masses of the Elements Acid Names from Anion Names Multiple Proportions 2.6 Elements: A First Look at the Binary Covalent Compounds The Simplest Organic Compounds: Dalton’s Atomic Theory Periodic Table 2.3 Straight-Chain Alkanes Postulates of the Atomic Theory Organization of the Periodic Table Masses from a Chemical Formula How the Atomic Theory Explains Classifying the Elements Representing Molecules with a the Mass Laws Compounds: An Introduction 2.7 Formula and a Model to Bonding 2.4 The Observations That Led to Mixtures: Classification and the Nuclear Atom Model The Formation of Ionic Compounds 2.9 Separation Discovery of the Electron and The Formation of Covalent An Overview of the Components of Its Properties Compounds Matter Discovery of the Atomic Nucleus (a) (b) (right) ©Rudy Umans/Shutterstock IN THIS CHAPTER . We examine the properties and composition of matter on the macroscopic and atomic scales. By the end of this chapter, you should be able to • Relate the three types of matter—elements or elementary substances, compounds, and mixtures—to the simple chemical entities that they comprise—atoms, ions, and molecules; -
Integrated M.Sc. Chemistry (CBCS) SYLLABUS Department of Chemistry Central University of Tamil Nadu Thiruvarur 610
Integrated M.Sc. Chemistry (CBCS) SYLLABUS Department of Chemistry Central University of Tamil Nadu Thiruvarur 610 101 Name of the course : Integrated M. Sc. (Chemistry) Duration : 10 semesters Intake : 30 Eligibility : Plus two examination or equivalent of any recognized board in India with 60% marks (Chemistry, Mathematics, Physics and Computer Science/Biology) for general category, 55% marks for OBC (Non-creamy layer) and 50% marks for SC/ST candidates. The candidates should not have completed 20 years of age as on 01-07-2015. Course Structure The five year program is spread into ten semesters where in first four semesters are designed for broad subject based understanding. Later six semesters will have increased focus on chemistry. The subject courses in the early stage of iM.Sc programme are simplified and of basic level that bolsters the inter-disciplinary way of learning. The third and subsequent year courses have been designed on advanced theories in chemistry with emphasis on concurrent modern laboratory techniques. Further the iM.Sc (Chemistry) programme has been included with experiments that provide exhaustive hands on experience on various sophisticated instruments, experimental techniques to enable the students secure jobs in corporate. The final semester is dedicated to specialization within the subject with research level training. The rules and regulations of Choice Based Credit System (CBCS) are applicable to this program. Generally, a student takes ten semesters to complete the program. The courses offered under CBCS, has certain credit number (2, 3 or 4). Core requirements of the programs are clearly defined. In the first two years of the program, a student has common course load with students from other departments. -
Specification for Low Alpha Lead in Wafer Bump Applications
Application Notes 47 Molter Street Cranston, Rhode Island 02910-1032 401-781-6100 • [email protected] • www.technic.com Specification for Low Alpha Lead in Wafer Bump Applications Background Alpha particles are positively charged nuclear particles consisting of two protons bound to two neutrons. Alpha particles are emitted spontaneously in some types of radioactive decay. Although alpha particle emissions are capable of penetrating only short distances, they are pernicious in creating computer memory or logic faults known as “soft faults”. Soft faults are individual events that are difficult to detect and isolate. Intel engineers working with IBM Fishkill, NY first identified the problem in 1979. The C-DIP’s (ceramic package DRAM) of that era were plated with gold and the alpha emissions were traced to the gold plated kovar package lids. Uranium or thorium decay and generate alpha particles with energies as high as 8.78 MeV. A flux of 5 MeV is capable of penetrating 25 um of silicon, resulting in 1.4 M electron hole pairs. If the electron accumulation exceeds a specific charge depending on the operating voltage and well design of the device, the cell may switch from “1” to “0”. There is no permanent damage and therefore the defect is referred to as a “soft” error. Design projections indicate that as device voltages decrease their sensitivity to alpha emissions increases. Alpha emissions are also common from tin lead deposited in the form of bumps for flip chip applications. The potential is significant for tin lead bumps due to the number of bumps and their close proximity to the sensitive IC well structure. -
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. -
ISOTOPIC ELEMENTS) and the WHOLE NUMBER RULE for ATOMIC WEIGHTS by William D
624 CHEMISTRY: W. D. HARKINS PROC. N. A. -S. -To summarize, the mechanism tentatively proposed above may be dia.. grammatically represented as follows: Insulin Glycogen-*Hexose ---Hexose mono-phosphate Hexose di-phosphate-<r-Triose phosphate and Reactive triose Carbon Lactic dioxide acid and Water 1 It has recently been noted from the Zentralblatt that Euler and Myrback (Svensk. Kem. Tidskr., 36, 295-306 (1924)) have made an apparently similar suggestion. As the originAl article has not been available it has been impossible to learn how closely the two theories coincide. 2R. Robison, Biochem. J., 16, 809 (1922). 'This step has been definitely established by Harden and his co-workers and the enzyme accomplishing the change has been named hexosephosphatase. 4 Neuberg and Kerb, Biocerm. Zs., 58, 158-170. (1913). ' Euler and Myrback, Chemie Zele Gewebe, 12, 57 (1925). THE SEPARATION OF CHLORINE INTO ISOTOPES (ISOTOPIC ELEMENTS) AND THE WHOLE NUMBER RULE FOR ATOMIC WEIGHTS By WILLiAM D. HARKINs KENT CHEMICAL LABORATORY, UNIvRSITY OP CHCAGO Comminicated August 26, 1925 Introduction.-The existence of isotopes among the heaviest or radio- active elements was demonstrated by the difference in the rays emitted by "different radioactive elements of almost identical chemical properties" now designated as isotopes of the same chemical element. Isotopes have been shown to exist in the light elements by two independent methods: by their detection in the positive ray method, and by the actual separation of the isotopes. The earliest use of the positive ray method for detecting isotopes by J. J. Thomson' resulted in the discovery of the isotopes of neon, while the separation of chlorine into isotopic fractions by Harkins and Downloaded by guest on September 25, 2021 VOL. -
(RAPID) Method to Nuclear Materials
University of Tennessee, Knoxville TRACE: Tennessee Research and Creative Exchange Doctoral Dissertations Graduate School 5-2020 Development and Applications of the Rapid Analysis of Post- Irradiation Debris (RAPID) Method to Nuclear Materials Emilie Fenske University of Tennessee, [email protected] Follow this and additional works at: https://trace.tennessee.edu/utk_graddiss Recommended Citation Fenske, Emilie, "Development and Applications of the Rapid Analysis of Post-Irradiation Debris (RAPID) Method to Nuclear Materials. " PhD diss., University of Tennessee, 2020. https://trace.tennessee.edu/utk_graddiss/5883 This Dissertation is brought to you for free and open access by the Graduate School at TRACE: Tennessee Research and Creative Exchange. It has been accepted for inclusion in Doctoral Dissertations by an authorized administrator of TRACE: Tennessee Research and Creative Exchange. For more information, please contact [email protected]. To the Graduate Council: I am submitting herewith a dissertation written by Emilie Fenske entitled "Development and Applications of the Rapid Analysis of Post-Irradiation Debris (RAPID) Method to Nuclear Materials." I have examined the final electronic copy of this dissertation for form and content and recommend that it be accepted in partial fulfillment of the equirr ements for the degree of Doctor of Philosophy, with a major in Nuclear Engineering. Howard Hall, Major Professor We have read this dissertation and recommend its acceptance: Steven Skutnik, Alan Icenhour, Robert Counce, Benjamin Roach, Cole Hexel Accepted for the Council: Dixie L. Thompson Vice Provost and Dean of the Graduate School (Original signatures are on file with official studentecor r ds.) Development and Applications of the Rapid Analysis of Post-Irradiation Debris (RAPID) Method to Nuclear Materials A Dissertation Presented for the Doctor of Philosophy Degree The University of Tennessee, Knoxville Emilie Fenske May 2020 Copyright © 2020 by Emilie Kiersten Fenske All rights reserved. -
Neutron 'Octaves'
Neutron `Octaves’ in the Moon Nuclear Model: A Harmonic Ordering of the Stable Isotopes1 Laurence Hecht May 18, 2007 Summary: When the stable isotopes are grouped according to the four Platonic solid shells, as described by the Moon model of the nucleus, the number of neutrons is found to fall in “octaves.” Thus, for the first 135 stable isotopes: 1H to 15N, number of neutrons = 0 to 8 16O to 30Si , number of neutrons = 8 to 16 31P to 58Fe, number of neutrons = 16 to 32 59Co to 110Pd, number of neutrons = 32 to 64. The Moon structure of the nucleus thus defines a periodicity in the gross ordering of the stable isotopes, somewhat analogous to the periods of the Mendeleyev table of the elements, but based on an implicit musical harmony. Introduction The ordering of the elements by atomic weight shows a periodicity discovered by Dmitri Mendeleyev in 1869. Mendeleyev found that increase in mass was not a linear property as suggested by Galileo and Newton, but rather evidenced a periodicity. When arranged in rows by order of increasing mass, properties including the propensity to chemical combination, valence, reactivity, melting and boiling points, crystal structure and others show a periodically repeating character, such that elements falling in the same 1 Author’s Note: Although the discovery reported here was subsumed within the previously published item, “A New Approach to the Ordering Principle of the Stable Isotopes” (21st Century Science & Technology, Fall 2007), it received insufficient elaboration there for the great majority of readers to grasp. This more complete and contemporaneous account of the discovery of the neutron “octaves” is provided to remedy that shortcoming (December 2, 2008). -
Thesis Front Matter
Research Report on Development of analytical strategies to measure radioisotopes of tin in the environment Prepared by Mohammad Majibur Rahman Graduate Program (PhD) Supervisor: Dr. Ian Clark Co-supervisor: Dr. Liam Kieser Earth and Environmental Sciences: Specialization in Chemical and Environmental Toxicology Submitted to The Office of Graduate and Postdoctoral Studies Submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy in Earth and Environmental Sciences: Specialization in Chemical and Environmental Toxicology DECEMBER 13, 2018 © Mohammad Majibur Rahman, Ottawa, Canada, 2018 This page has intentionally been left blank. Abstract Quantification of tin isotopes in environmental samples, particularly the radioactive 126Sn, is important for processes such as the biomonitoring of organotin species, long-term nuclear waste storage and treatment planning. The detection of 126Sn by mass spectrometric methods is, however, hampered by the presence of the stable 126Te isotope. Therefore, separation of tin from tellurium is crucial to minimize isobaric interferences that limit the quantification of 126Sn by Accelerator Mass Spectrometry (AMS) and other instrumental techniques. In the present study, three major accomplishments are discussed: i) development of an analytical strategy to separate tin from tellurium, ii) monitoring of anionic interferences in the separation of tin from tellurium, and iii) suppression of 126Te background to allow the detection of 126Sn by AMS. Section I (Chapter 2): In the first phase of the project, an analytical survey was carried out using four Eichrom resins (TRU, TEVA, UTEVA, and DGA) to identify a suitable solid phase chromatographic material to separate tin from tellurium. Standard metal solutions were spiked on batch tests in two acids (HCl and HNO3) at concentrations ranging from 0.20 to 6.0 mol L–1, and the spiked analytes in solution were measured by ICP-MS. -
DOCUMENT RESUME ED 071 911 SE 015 548 TITLE Project Physics
DOCUMENT RESUME ED 071 911 SE 015 548 TITLE Project Physics Teacher Guide 6, The Nucleus. INSTITUTION Harvard Univ., Cambridge, Mass. Harvard Project Physics. SPONS AGENCY Office of Education (DHEW) Washington, D.C. Bureau of Research. BUREAU NO BR-5-1038 PUB DATE 68 CONTRACT OEC-5-10-058 NOTE 235p.; Authorized Interim Version EDRS PRICE MF-$0.65 HC-S9.87 DESCRIPTORS Instructional Materials; *Multimedia Instruction; *Nuclear Physics; Physics; *Radiation; Science Activities; Secondary Grades; *Secondary School Science; *Teaching Glides; Teaching Procedures IDENTIFIERS Harvard Project Physics ABSTRACT Teaching procedures of Project Physics Unit 6are presented to help teachers make effectiveuse of learning materials. Unit contents are discussed in connection withteaching aid lists, multi-media schedules, schedule blocks, andresource charts. Brief summaries are made for transparencies, 16mm films, and reader articles. Included is information about the backgroundand development of each unit chapter, procedures in demonstrations, apparatus operations, notes on the student handbook, andan explanation of film loops. Additional articlesare concerned with objects dated by radiocarbon, radiation safety, propertiesof radiations, radioactive sources, radioactivity determinationby electroscopes, and radiation detecting devices.Scalers, counters, Geiger tubes, and cadmium selenide photocellsare analyzed; and a bibliography of references is given, Solutionsto the study guide are provided in detail, and answers to test itemsare suggested. The sixth unit of the text, with marginal commentson each section, is also compiled in the manual. The work of Harvard ProjectPhysics has . been financially supported by: the Carnegie Corporation ofNew York, the Ford Foundation, the National Science Foundation,the Alfred P. Sloan Foundation, the United States office of Education,and Harvard University. -
Advanced Chemistry 1
ADVANCED CHEMISTRY 1 Philip Matthews B&& CAMBRIDGE UNIVERSITY PRESS Contents Acknowledgements pagex 5 Radioactive decay 28 How to use this book xi 5.1 Detection of radiation 28 5.2 Half-lives 29 5.3 The radioactive decay law 31 5.4 Decay schemes 31 PHYSICAL CHEMISTRY 6 Nuclear energy 34 1 Elements, atoms and electrons: basic 6.1 Discovery of nuclear energy 34 ideas 3 6.2 Fission reactions 34 1.1 Dalton's atomic theory 3 6.3 Nuclear power 35 1.2 Evidence for atoms 5 6.4 Fusion reactions 37 1.3 Cathode rays 6 6.5 Nuclear weapons 38 1.4 Millikan's experiment 6 1.5 Electric Charge is quantised 7 7 Applications of radioactivity 41 7.1 Industrial uses of radioactivity 41 2 Energy levels 9 7.2 Medical uses of radioactivity 42 2.1 Energy changes 9 7.3 Radiocarbon dating 42 2.2 Energy levels 9 7.4 Chemical applications 43 2.3 Max Planck and energy levels 11 2.4 Light energy 11 8 Bohr's model of the atom 46 8.1 Energy levels of the hydrogen atom 46 3 Atoms and the nucleus 13 8.2 How to calculate the ionisation energy of 3.1 A plum pudding 13 hydrogen 47 3.2 How the nucleus was discovered 13 8.3 What are Orbitals? 48 3.3 The discovery of protons 14 8.4 What are stationary states? 48 3.4 Moseley and atomic number 15 8.5 Ground and excited states 49 3.5 Discovery of neutrons 15 3.6 A comparison of electrons, protons and 9 The hydrogen atom spectrum 51 neutrons 16 9.1 Balmer's formula for the hydrogen atom 51 3.7 Isotopes 17 9.2 Bohr's explanation 51 3.8 Atomic mass units 17 9.3 Other lines in the hydrogen spectrum 51 3.9 Relative atomic and molecular -
Project Physics Text 6, the Nucleus. INSTITUTION Harvard Univ., Cambridge, Mass
DOCUMENT RESUME ED 071 910 SE 015 547 TITLE Project Physics Text 6, The Nucleus. INSTITUTION Harvard Univ., Cambridge, Mass. Harvard Protect Physics. SPONS AGENCY Office of Education (DHEW), Washington, D.C. Bureau of Research. BUREAU NO BR-5-1038 .PUB DATE 68 CONTRACT OEC-5-1C-058 NOTE 128p.; Authorized Interim Version EDRS PRICE brio-$0.65 HC -$6.58 DESCRIPTORS Instructional Materials; *Nuclear Physics; Physics; *Radiation; Radiation Effects; Radioisotopes; *Scientific Concepts; Secondary Grades; *Secondary School Science; *Textbooks IDENTIFIERS Harvard Project Physics ABSTRACT Nuclear physics fundamentals are presented in this sixth unit of the Project Physics text for use by senior high students. Included are discussions of radioactivity, taking into account Bacquerells discovery, radioactive elements, properties of radiations, radioactive transformations, decay series, and half-lives. Isotopes are analyzed in connection with positiverays, mass spectrographs, notations for nuclides and nuclear reactions, relative abundances, and atomic masses. Nuclear structures and reactions are studied by using proton-electron and proton-neutron hypotheses with a background of discoveries of neutrons, neutrinosas well as artificial transmutation and artificially induced radioactivity. Information about binding energy,mass-energy balance, nuclear fission and fusion, stellar nuclear reactions, nuclear force and model, and biological and medical application of radioisotopes is, given to conclude the whole text. Historical developmentsare stressed in -
William Draper Harkins
NATIONAL ACADEMY OF SCIENCES WILLIAM DRAPER H ARKINS 1873—1951 A Biographical Memoir by RO B E R T S . M ULLIKEN Any opinions expressed in this memoir are those of the author(s) and do not necessarily reflect the views of the National Academy of Sciences. Biographical Memoir COPYRIGHT 1975 NATIONAL ACADEMY OF SCIENCES WASHINGTON D.C. WILLIAM DRAPER HARKINS December 28, 1873-March 7', 1951 BY ROBERT S. MULLIKEN ILLIAM DRAPER HARKINS was a remarkable man. Although W he was rather late in beginning his career as professor of physical chemistry, his success was outstanding. He was a leader in nuclear physics at a time when American physicists were paying no attention to nuclei. Besides this, his work in chem- istry covers a broad range of physical chemistry, with especial emphasis on surface phenomena. He was a meticulous and re- sourceful experimenter, as well as an enterprising one, who did not hesitate to enter new fields and use new techniques. He participated broadly, not only in the development of pure science but also in its industrial applications. Harkins was born December 28, 1873, the son of Nelson Goodrich Harkins and Sarah Eliza (Draper) Harkins, in Titus- ville, Pennsylvania, then the heart of the new, booming oil industry. At the age of seven, he invested his entire capital of $12 in an oil well that his father had drilled in the Bradford, Pennsylvania, fields. This investment returned his capital several times. Fortunately for science, the returns were not great enough to attract him permanently into oil production. In 1892, at the age of nineteen, Harkins went to Escondido, California, near San Diego, to study Greek at the Escondido Seminary, a branch of the University of Southern California.