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Understanding the Bonding of Second Period Diatomic Molecules Spdf Vs MCAS
Understanding the Bonding of Second Period Diatomic Molecules Spdf vs MCAS By Joel M Williams (text and images © 2013) The html version with updates and higher resolution images is at the author’s website (click here) Abstract The current spdf and MO modeling of chemical molecules are well-established, but do so by continuing to assume that non-classical physics is operating. The MCAS electron orbital model is an alternate particulate model based on classical physics. This paper describes its application to the diatomic molecules of the second period of the periodic table. In doing so, it addresses their molecular electrostatics, bond strengths, and electron affinities. Particular attention is given to the anomalies of the carbon diatom. Questions are raised about the sensibleness of the spdf model’s spatial ability to contain two electrons on an axis between diatoms and its ability to form π-bonds from parallel p-orbitals located over the nuclei of each atom. Nitrogen, carbon monoxide, oxygen, and fluorine all have the same inter-nuclei bonding: all “triple bonds” of varying strength caused by different numbers of anti-bonding electrons. The spdf model was devised for single atoms by physicists and mathematicians. Kowtowing to them, chemists produce hybrid orbitals to explain how atoms could actually form molecules. Drawing these hybrids and meshing them on paper might look great, but, constrained to measured interatomic physical dimensions and electrostatic interactions, bonding based on the spdf-hybrids (sp, sp2, sp3) is illogical. To have even one electron occupy the “bond” region between the nuclei of diatomic molecules, at the expense of reduced coverage elsewhere, does not make sense for stable molecules. -
Determination of Aluminium As Oxide
DETERMINATION OF ALUMINIUM AS OXIDE By William Blum CONTENTS Page I. Introduction 515 II. General principles 516 III. Historical 516 IV. Precipitation of aluminium hydroxide. 518 1. Hydrogen electrode studies 518 (a) The method 518 (b) Apparatus and solutions employed 518 (c) Results of hydrogen electrode experiments 519 (d) Conclusions from hydrogen electrode experiments 520 2. Selection of an indicator for denning the conditions of precipita- '. tion . 522 3. Factors affecting the form of the precipitate 524 4. Precipitation in the presence of iron 525 V. Washing the precipitate . 525 VI. Separation from other elements 526 VII. Ignition and weighing of the precipitate 528 1. Hygroscopicity of aluminium oxide 529 2. Temperature and time of ignition 529 3. Effect of ammonium chloride upon the ignition 531 VIII. Procedure recommended 532 IX. Confirmatory experiments 532 X. Conclusions '534 I. INTRODUCTION Although a considerable number of precipitants have been pro- posed for the determination of aluminium, direct precipitation of aluminium hydroxide by means of ammonium hydroxide, fol- lowed by ignition to oxide, is most commonly used, especially if no separation from iron is desired, in which latter case special methods must be employed. While the general principles involved in this determination are extremely simple, it has long been recog- nized that certain precautions in the precipitation, washing, and ignition are necessary if accurate results are to be obtained. While, however, most of these details have been studied and dis- cussed by numerous authors, it is noteworthy that few publica- tions or textbooks have taken account of all the factors. In the 515 ; 516 Bulletin of the Bureau of Standards [Voi.i3 present paper it seems desirable, therefore, to assemble the various recommendations and to consider their basis and their accuracy. -
Discharge Plasmas of Molecular Gases
/ J ¥4~r~~~: 'o j~ ~7 ~,~U;~I u t= ~]f~LL*~ ~~~~~~; 4. Isotope Separation in Discharge Plasmas of Molecular Gases EZOUBTCHENKO, Alexandre N.t, AKATSUKA Hiroshi and SUZUKI Masaaki Research Laboratory for Nuclear Reactors, Tokyo Institute of Technology, Tokyo 152-8550, Japan (Received 25 December 1997) Abstract We review the theoretical principles and the experimental methods of isotope separation achieved through the use of discharge plasmas of molecular gases. Isotope separation has been accomplished in various plasma chemical reactions. It is experimentally and theoretically shown that a state of non- equilibrium in the plasmas, especially in the vibrational distribution functions, is essential for the isotope redistribution in the reagents and products. Examples of the reactions, together with the isotope separ- ation factors known up to the present time, are shown to separate isotopic species of carbon, nitrogen and oxygen molecules in the plasma phase, generated by glow discharge and microwave discharge. Keywords: isotope separation, vibrational nonequilibrium, glow discharge, microwave discharge, plasma chemistry 4.1 Introduction isotopic species will be redistributed between the rea- Plasmas generated by electric discharge of molecu- gents and the products. We can elaborate a new lar gases under moderate pressures (10 Torr < p < method of the plasma isotope separation for light ele- 200 Torr) are usually in a state of nonequilibrium. We ments . can define various temperatures according to the kine- There were a few experimental studies of isotope tics of various particles in such plasmas, for example, separation phenomena in the nonequilibrium electric electron temperature ( T*), gas translational temperature discharge. Semiokhin et al. measured C02 enrichment ( To), gas rotational temperature ( TR) and vibrational in i3C02 and 12C160180 with a separation factor a ~ temperature ( Tv), where the relationships T* > Tv ;~ 1.01 in the C02 Silent (barrier) discharge in the pres- TR- To usually hold. -
©2018 Alexander Hook ALL RIGHTS RESERVED
©2018 Alexander Hook ALL RIGHTS RESERVED A DFT STUDY OF HYDROGEN ABSTRACTION FROM LIGHT ALKANES: Pt ALLOY DEHYDROGENATION CATALYSTS AND TIO2 STEAM REFORMING CATALYSTS By ALEXANDER HOOK A dissertation submitted to the School of Graduate Studies Rutgers, The State University of New Jersey In partial fulfillment of the requirements For the degree of Doctor of Philosophy Graduate Program in Chemical and Biochemical Engineering Written under the direction of Fuat E. Celik And approved by __________________________ __________________________ __________________________ __________________________ New Brunswick, New Jersey May, 2018 ABSTRACT OF THE DISSERTATION A DFT STUDY OF HYDROGEN ABSTRACTION FROM LIGHT ALKANES: Pt ALLOY DEHYDROGENATION CATALYSTS AND TiO2 STEAM REFORMING CATALYSTS By ALEC HOOK Dissertation Director: Fuat E. Celik Sustainable energy production is one of the biggest challenges of the 21st century. This includes effective utilization of carbon-neutral energy resources as well as clean end-use application that do not emit CO2 and other pollutants. Hydrogen gas can potentially solve the latter problem, as a clean burning fuel with very high thermodynamic energy conversion efficiency in fuel cells. In this work we will be discussing two methods of obtaining hydrogen. The first is as a byproduct of light alkane dehydrogenation where we obtain a high value olefin along with hydrogen gas. The second is in methane steam reforming where hydrogen is the primary product. Chapter 1 begins by introducing the reader to the current state of the energy industry. Afterwards there is an overview of what density functional theory (DFT) is and how this computational technique can elucidate and complement laboratory experiments. It will also contain the general parameters and methodology of the VASP software package that runs the DFT calculations. -
A Dicationic Iminophosphane Ying Kai Loh, Chitra Gurnani, Rakesh Ganguly, and Dragoslav Vidović*
A Dicationic Iminophosphane Ying Kai Loh, Chitra Gurnani, Rakesh Ganguly, and Dragoslav Vidović* Department of Chemistry and Biological Chemistry, Nanyang Technological University, 21 Nanyang Link, Singapore, 637371. Supporting Information Placeholder ABSTRACT: A novel dicationic system containing a PN frag- ment has been synthesized and structurally characterized. Accord- ing to the solid state analysis and theoretical investigation the dica- tionic iminophosphane resonance from is the most appropriate de- scription for the dication. However, the contribution from the phos- phorus mononitride resonance form is not negligible. Neutral two-eletron donor carbenes have proven to be quite versatile ligands for isolation of a wide variety of novel main group 1-4 species. Examples include diatomic allotropes (L-E2-L; L = car- bene, E = B, Si, Ge, P, As, etc)1a of boron, silicon, germanium, phosphorus, arsenic, etc.2-4 Nevertheless, these interesting mole- cules, among numerous other main group species, sparked a debate about the most appropriate way to describe bonding in these com- Figure 1. Recently isolated neutral (A) and radical cationic (B) 5,6 pounds. In particular, the arguments have been focused on phosphorus mononitrides, and general structure for carbones (C). whether the carbene moieties form typical covalent bonds or the Dipp = 2,6-diisopropylphenyl. use of dative bond analogy is also valid. The latest evidence showed that the L-E bonds for L-B2-L are quite strong suggesting a sub- stantial covalent character.6 However, Frenking argued that dative The overall synthesis of the target dication is summarized in bonds could be also very strong by the combination of -donation Scheme 1. -
Chapter 10 Theories of Electronic Molecular Structure
Chapter 10 Theories of Electronic Molecular Structure Solving the Schrödinger equation for a molecule first requires specifying the Hamiltonian and then finding the wavefunctions that satisfy the equation. The wavefunctions involve the coordinates of all the nuclei and electrons that comprise the molecule. The complete molecular Hamiltonian consists of several terms. The nuclear and electronic kinetic energy operators account for the motion of all of the nuclei and electrons. The Coulomb potential energy terms account for the interactions between the nuclei, the electrons, and the nuclei and electrons. Other terms account for the interactions between all the magnetic dipole moments and the interactions with any external electric or magnetic fields. The charge distribution of an atomic nucleus is not always spherical and, when appropriate, this asymmetry must be taken into account as well as the relativistic effect that a moving electron experiences as a change in mass. This complete Hamiltonian is too complicated and is not needed for many situations. In practice, only the terms that are essential for the purpose at hand are included. Consequently in the absence of external fields, interest in spin- spin and spin-orbit interactions, and in electron and nuclear magnetic resonance spectroscopy (ESR and NMR), the molecular Hamiltonian usually is considered to consist only of the kinetic and potential energy terms, and the Born- Oppenheimer approximation is made in order to separate the nuclear and electronic motion. In general, electronic wavefunctions for molecules are constructed from approximate one-electron wavefunctions. These one-electron functions are called molecular orbitals. The expectation value expression for the energy is used to optimize these functions, i.e. -
Alcl3(G)=3Alcl(G) Reaction in the Subhalide Process of Aluminium (Study of Extractive Metallurgy of Aluminium (1))
Equilibrium of the 2Al(l)+AlCl3(g)=3AlCl(g) Reaction in the Subhalide Process of Aluminium (Study of Extractive Metallurgy of Aluminium (1)) By Takeaki Kikuchi*, Toshio Kurosawa* and Testuo Yagihashi* Equilibriumconstants of a fundamental reaction of the aluminium subhalide process, 2Al(l)+AlCl3(g)= 3AlCl(g), were determined by the flow method using argon carrier between 1000℃ and 1250℃. As a result of this experiment, equilibrium constants and standard free energy were obtained by the following equation: The heat of formation and entropy of AlCl(g) obtained from the experimental data and other thermodynamic values were -22,250cal/mot and 48.7cal/mol respectively. By the use of the equilibrium constants, the reaction ratio of aluminium trichloride was calculated at a reduced pressure and in argon carrier, respectively. (Receivedmarch 10, 1964) I. Introduction trichloride supplied to the reaction zone were applied Aluminium is produced by means of the fused salt previously. In this investigation, the latter method electrolysis using alumina obtained mainly from rela- was selected to obtain the equilibrium constants. tively higher grade bauxite. However, another 1. Experimental apparatus extraction method called the Gross or subhalide process has recently been investigated, and some technological The apparatus used in this experiment is shown by or industrialization reports have already been the schematic diagram in Fig. 1. The apparatus con- sists of an argon purifier, aluminium trichloride evapora- published. In this process, crude aluminium alloy is produced tor, reaction tube, and condensing tube of aluminium by reduction of alumina bearing ores with carbonaceous trichloride gas. Argon in a bomb was purified and reducing material such as coke or charcoal in the measured by passing through concentrated sulphuric acid, calcium chloride, soda lime, phosphorus pentoxide first step, and then aluminium trichloride gas is alld magnesium chip hea七ed at 400℃. -
Injection of Meteoric Phosphorus Into Planetary Atmospheres
Planetary and Space Science 187 (2020) 104926 Contents lists available at ScienceDirect Planetary and Space Science journal homepage: www.elsevier.com/locate/pss Injection of meteoric phosphorus into planetary atmospheres Juan Diego Carrillo-Sanchez a, David L. Bones a, Kevin M. Douglas a, George J. Flynn b, Sue Wirick c, Bruce Fegley Jr. d, Tohru Araki e, Burkhard Kaulich e, John M.C. Plane a,* a School of Chemistry, University of Leeds, Woodhouse Lane, Leeds, LS2 9JT, UK b State University of New York at Plattsburgh, Department of Physics, 101 Broad Street, Plattsburg, NY, 12901, USA c Focused Beam Enterprises, Westhampton, NY, 11977, USA d Planetary Chemistry Laboratory, Department of Earth & Planetary Sciences and McDonnell Center for the Space Sciences, Washington University, St Louis, MO, 63130, USA e Diamond Light Source Ltd, Harwell Science & Innovation Campus, Didcot, OX11 0DE, UK ARTICLE INFO ABSTRACT Keywords: This study explores the delivery of phosphorus to the upper atmospheres of Earth, Mars, and Venus via the Cosmic dust ablation of cosmic dust particles. Micron-size meteoritic particles were flash heated to temperatures as high as Planetary atmospheres 2900 K in a Meteor Ablation Simulator (MASI), and the ablation of PO and Ca recorded simultaneously by laser Ablation induced fluorescence. Apatite grains were also ablated as a reference. The speciation of P in anhydrous chondritic Phosphorus thermodynamics porous Interplanetary Dust Particles was made by K-edge X-ray absorption near edge structure (XANES) spec- Zodiacal cloud troscopy, demonstrating that P mainly occurs in phosphate-like domains. A thermodynamic model of P in a sil- icate melt was then developed for inclusion in the Leeds Chemical Ablation Model (CABMOD). -
Diatomic Carbon Measurements with Laser-Induced Breakdown Spectroscopy
University of Tennessee, Knoxville TRACE: Tennessee Research and Creative Exchange Masters Theses Graduate School 5-2015 Diatomic Carbon Measurements with Laser-Induced Breakdown Spectroscopy Michael Jonathan Witte University of Tennessee - Knoxville, [email protected] Follow this and additional works at: https://trace.tennessee.edu/utk_gradthes Part of the Atomic, Molecular and Optical Physics Commons, and the Plasma and Beam Physics Commons Recommended Citation Witte, Michael Jonathan, "Diatomic Carbon Measurements with Laser-Induced Breakdown Spectroscopy. " Master's Thesis, University of Tennessee, 2015. https://trace.tennessee.edu/utk_gradthes/3423 This Thesis 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 Masters Theses 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 thesis written by Michael Jonathan Witte entitled "Diatomic Carbon Measurements with Laser-Induced Breakdown Spectroscopy." I have examined the final electronic copy of this thesis for form and content and recommend that it be accepted in partial fulfillment of the equirr ements for the degree of Master of Science, with a major in Physics. Christian G. Parigger, Major Professor We have read this thesis and recommend its acceptance: Horace Crater, Joseph Majdalani Accepted for the Council: Carolyn R. Hodges Vice Provost and Dean of the Graduate School (Original signatures are on file with official studentecor r ds.) Diatomic Carbon Measurements with Laser-Induced Breakdown Spectroscopy A Thesis Presented for the Master of Science Degree The University of Tennessee, Knoxville Michael Jonathan Witte May 2015 c by Michael Jonathan Witte, 2015 All Rights Reserved. -
Fullerenes and Pahs: a Novel Model Explains Their Formation Via
Fullerenes and PAHs: A Novel Model Explains their Formation via Sequential Cycloaddition Reactions Involving C2 Dimers Sylvain L. Smadja [email protected] 10364 Almayo Ave., Suite 304 Los Angeles, CA 90064 “Cove” region closure C20 bowl + 10C2 creates pentagonal ring C50 + 5C2 [2 + 2 + 2] [4 + 2] Cycloadditions Cycloadditions Cage 5C 5C 2 2 closure “Cove” region C40 C50 C60 Buckministerfullerene ABSTRACT: Based on a new understanding of the nature of the bonding in the C2 dimer, a novel bottom-up model is offered that can explain the growth processes of fullerenes and polycyclic aromatic hydrocarbons (PAHs). It is shown how growth sequences involving C2 dimers, that take place in carbon vapor, combustion systems, and the ISM, could give rise to a variety of bare carbon clusters. Among the bare carbon clusters thus formed, some could lead to fullerenes, while others, after hydrogenation, could lead to PAHs. We propose that the formation of hexagonal rings present in these bare carbon clusters are the result of [2+2+2] and [4+2] cycloaddition reactions that involve C2 dimers. In the C60 and C70 fullerenes, each of the twelve pentagons is surrounded by five hexagons and thereby “isolated” from each other. To explain why, we suggest that in bowl-shaped clusters the pentagons can form as the consequence of closures of “cove regions” that exist between hexagonal rings, and that they can also form during cage-closure, which results in the creation of six “isolated” pentagonal rings, and five hexagonal rings. The proposed growth mechanisms can account for the formation of fullerene isomers without the need to invoke the widely used Stone-Wales rearrangement. -
(12) United States Patent (10) Patent No.: US 8,753,759 B2 Liao (45) Date of Patent: *Jun
USOO8753759B2 (12) United States Patent (10) Patent No.: US 8,753,759 B2 Liao (45) Date of Patent: *Jun. 17, 2014 (54) BATTERY WITH CHLOROPHYLL 5,270,137 A * 12/1993 Kubota ......................... 429,249 ELECTRODE 5,928,714 A * 7/1999 Nunome et al. ........... 427,126.3 6,511,774 B1 1/2003 Tsukuda et al. 6,905,798 B2 6/2005 Tsukuda et al. (75) Inventor: Chungpin Liao, Taichung (TW) 7,405,172 B2 7/2008 Shigematsu et al. 2009/0325067 A1 12/2009 Liao et al. (73) Assignee: iNNOT BioEnergy Holding Co., George Town (KY) FOREIGN PATENT DOCUMENTS *) Notice: Subject to anyy disclaimer, the term of this TW I288495 B 10/2007 patent is extended or adjusted under 35 U.S.C. 154(b) by 460 days. OTHER PUBLICATIONS This patent is Subject to a terminal dis Dryhurst, Glenn, “Electrochemistry of Biological Molecules' claimer. Elsevier, Inc. (1977), pp. 408-415.* (21) Appl. No.: 13/075,909 * cited by examiner (22) Filed: Mar. 30, 2011 (65) Prior Publication Data Primary Examiner — Zachary Best (74) Attorney, Agent, or Firm — Novak Druce Connolly US 2012/O 148898A1 Jun. 14, 2012 Bove + Quigg LLP (30) Foreign Application Priority Data (57) ABSTRACT Dec. 13, 2010 (CN) .......................... 2010 1 0.585281 An exemplary battery is provided in the present invention. (51) Int. Cl. The battery includes a current collector, a positive-electrode HOLM 8/6 (2006.01) structure, a separation structure, a negative-electrode struc (52) U.S. Cl. ture and a housing. The positive-electrode structure, the sepa USPC ............................. 429/2; 429/218.1; 429/212 ration structure, the negative-electrode structure are encircled (58) Field of Classification Search in sequence inside of the housing. -
Barc Progress Report - 1996
IN9800956 n0 BARC PROGRESS REPORT - 1996 1997 ... x ** BARC/1997/P/003 GOVERNMENT OF INDIA ATOMIC ENERGY COMMISSION < co BARC PROGRESS REPORT - 1996 BHABHA ATOMIC RESEARCH CENTRE MUMBAI, INDIA 1997 BARC/1997/P/003 BIBLIOBRAPHIC DESCRIPTION SHEET FOR TECHNICAL REPORT (as psr IS : 9400 - 19S0) 01 Security classification : Unclassified 02 Distribution : External 03 Report status : New 04 Series t BARC External 05 Report type : Progress Report 06 Report No. : BARC/1997/P/003 07 Part No. or Volume No. i 08 Contract No. i 10 Title and subtitle t BARC Progress Report - 1996 11 Collation i 37JTp. 13 Project No. s 20 Personal author (s) 21 Affiliation of author (s): 22 Corporate author(s> s Bhabha Atomic Research Centre, Mumbai-400 085 23 Originating unit : Library and Information Services Division, BARC, Mumbai 24 Sponsor(s) Name : Department of Atomic Energy Type t Government 30 Date of submission : October 1997 31 Publication/Issue data November 1997 contd...(lb) 40 Publisher/Distributor : Head, Library and Information Di vi sion, Bhabha Atomic Research Centre, Mumbai 42 Form of distribution : Hard Copy 50 Language o-f text : English 51 Language o-f summary : English 52 No. of references J 53 Given data on : 60 Abstract : This report summarises the various activities and research and development programmes of the different Divisions of the Bhabha Atomic Research Centre, Mumbai. The list of publications and papers presented at various conferences, symposia, workshops etc and papers published in various journals by the staff members of the different Divisions arB also given. 70 Keywords/Descriptors : BARC; RESEARCH PROGRAMS; PROGRESS REPORT; ACCELERATORS; NUCLEAR FUELS; NUCLEAR PHYSICS; RADIOCHEMISTRY; COMPUTERS; BIOLOGY; MATERIALS; RADIATIONS; SAFETY; REACTOR PHYSICS; LASERS; NUCLEAR MEDICINE 71 INIS Subject Category : F6000 99 Supplementary elements : fcoo TROMIiAY.