Directed Gas Phase Formation of Silicon Dioxide and Implications for the Formation of Interstellar Silicates
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Summary Tables of Calculated and Experimental Parameters Of
Summary Tables of Calculated and Experimental Parameters of Diatomic, Triatomic, Organic, Silicon, Boron, Aluminum and Organometallic Molecules, Exemplary Results on Condensed Matter Physics, One-Through Twenty-Electron Atoms, Excited States of Helium, g Factor, and Fundamental Particle Masses The closed-form derivations from Maxwell's equations given in The Grand Unified Theory of Classical Physics posted at http://www.blacklightpower.com/theory/bookdownload.shtml contain fundamental constants only. The nature of the chemical bond is given in Chapters 12 through 15. The atoms are solved exactly in Chapters 1, 7, and 10. The excited states of helium are solved exactly in Chapter 9. The electron g factor and relations between fundamental particles are given in Chapter 1 and Chapters 36, 37 and 38. Tables summarizing the results of the calculated experimental parameters of 800 exemplary solved molecules follow. The closed-form derivations of these molecules can be found in The Grand Theory of Classical Physics posted at http://www.blacklightpower.com/theory/bookdownload.shtml Chapters 15–17, as well as Silicon in Chapter 20, Boron in Chapter 22, and Aluminum and Organometallics in Chapter 23. Condensed matter physics based on first principles with analytical solutions of (i) of the geometrical parameters and energies of the hydrogen bond of H2O in the ice and steam phases, and of H2O and NH3; (ii) analytical solutions of the geometrical parameters and interplane van der Waals cohesive energy of graphite; (iii) analytical solutions of the geometrical parameters and interatomic van der Waals cohesive energy of liquid helium and solid neon, argon, krypton, and xenon are given in Chapter 16. -
Carbothermal Synthesis of Silicon Nitride
Carbothermal Synthesis of Silicon Nitride Xiaohan Wan A thesis in fulfilment of the requirements for the degree of Doctor of Philosophy School of Materials Science and Engineering Faculty of Science March 2013 THE UNIVERSITY OF NEW SOUTH WALES Thesis/Dissertation Sheet Surname or Family name: Wan First name: Xiaohan Other name/s: Abbreviation for degree as given in the University calendar: PhD School: Materials Science and Engineering Faculty: Science Title: Carbothermal synthesis of silicon nitride Abstract 350 words maximum Carbothermal synthesis of silicon nitride Si3N4 followed by decomposition of Si3N4 is a novel approach to production of solar-grade silicon. The aim of the project was to study reduction/nitridation of silica under different conditions and to establish mechanism of silicon nitride formation. Carbothermal reduction of quartz and amorphous silica was investigated in a fixed bed reactor at 1300-1650 °C in nitrogen at 1-11 atm pressure and in hydrogen-nitrogen mixtures at atmospheric pressure. Samples were prepared from silica-graphite mixtures in the form of pellets. Carbon monoxide evolution in the reduction process was monitored using an infrared sensor; oxygen, nitrogen and carbon contents in reduced samples were determined by LECO analyses. Phases formed in the reduction process were analysed by XRD. Silica was reduced to silicon nitride and silicon carbide; their ratio was dependent on reduction time, temperature and nitrogen pressure. Reduction products also included SiO gas which was removed from the pellet with the flowing gas. In the experiments, reduction of silica started below 1300 °C; the reduction rate increased with increasing temperature. Silicon carbide was the major reduction product at the early stage of reduction; the fraction of silicon nitride increased with increasing reaction time. -
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. -
The Preparation and Reactions of the Lower Chlorides and Oxychlorides of Silicon Joseph Bradley Quig Iowa State College
Iowa State University Capstones, Theses and Retrospective Theses and Dissertations Dissertations 1926 The preparation and reactions of the lower chlorides and oxychlorides of silicon Joseph Bradley Quig Iowa State College Follow this and additional works at: https://lib.dr.iastate.edu/rtd Part of the Inorganic Chemistry Commons Recommended Citation Quig, Joseph Bradley, "The preparation and reactions of the lower chlorides and oxychlorides of silicon " (1926). Retrospective Theses and Dissertations. 14278. https://lib.dr.iastate.edu/rtd/14278 This Dissertation is brought to you for free and open access by the Iowa State University Capstones, Theses and Dissertations at Iowa State University Digital Repository. It has been accepted for inclusion in Retrospective Theses and Dissertations by an authorized administrator of Iowa State University Digital Repository. For more information, please contact [email protected]. INFORMATION TO USERS This manuscript has been reproduced from the microfilm master. UlVli films the text directly from the original or copy submitted. Thus, some thesis and dissertation copies are in typewriter face, while others may be from any type of computer printer. The quality of this reproduction is dependent upon the quality of the copy submitted. Broken or indistinct print, colored or poor quality illustrations and photographs, print bleedthrough, substandard margins, and impiroper alignment can adversely affect reproduction. In the unlikely event that the author did not send UMI a complete manuscript and there are missing pages, these will be noted. Also, if unauthorized copyright material had to be removed, a note will indicate the deletion. Oversize materials (e.g., maps, drawings, charts) are reproduced by sectioning the original, beginning at the upper left-hand corner and continuing from left to right in equal sections with small overiaps. -
Unit 2 Matter and Chemical Change
TOPIC 5 The Periodic Table By the 1850s, chemists had identified a total of 58 elements, and nobody knew how many more there might be. Chemists attempted to create a classification system that would organize their observations. The various “family” systems were useful for some elements, but most family relationships were not obvious. What else could a classification system be based on? By the 1860s several scientists were trying to sort the known elements according to atomic mass. Atomic mass is the average mass of an atom of an element. According to Dalton’s atomic theory, each element had its own kind of atom with a specific atomic mass, different from the Figure 2.31 Dmitri atomic mass of any other elements. One scientist created a system that Ivanovich Mendeleev was so accurate it is still used today. He was a Russian chemist named was born in Siberia, the Dmitri Mendeleev (1834–1907). youngest of 17 children. Mendeleev Builds a Table Mendeleev made a card for each known element. On each card, he put data similar to the data you see in Figure 2.32. Figure 2.32 The card above shows modern values for silicon, rather than the ones Mendeleev actually used. His values were surprisingly close to modern ones. The atomic mass measurement indicates that silicon is 28.1 times heavier than hydrogen. You can observe other properties of silicon in Figure 2.33. Mendeleev pinned all the cards to the wall, in order of increasing atomic mass. He “played cards” for several Figure 2.33 The element silicon is melted months, arranging the elements in vertical columns and and formed into a crystal. -
A Chemical Kinetics Network for Lightning and Life in Planetary Atmospheres P
View metadata, citation and similar papers at core.ac.uk brought to you by CORE provided by St Andrews Research Repository The Astrophysical Journal Supplement Series, 224:9 (33pp), 2016 May doi:10.3847/0067-0049/224/1/9 © 2016. The American Astronomical Society. All rights reserved. A CHEMICAL KINETICS NETWORK FOR LIGHTNING AND LIFE IN PLANETARY ATMOSPHERES P. B. Rimmer and Ch Helling School of Physics and Astronomy, University of St Andrews, St Andrews, KY16 9SS, UK; [email protected] Received 2015 June 3; accepted 2015 October 22; published 2016 May 23 ABSTRACT There are many open questions about prebiotic chemistry in both planetary and exoplanetary environments. The increasing number of known exoplanets and other ultra-cool, substellar objects has propelled the desire to detect life andprebiotic chemistry outside the solar system. We present an ion–neutral chemical network constructed from scratch, STAND2015, that treats hydrogen, nitrogen, carbon, and oxygen chemistry accurately within a temperature range between 100 and 30,000 K. Formation pathways for glycine and other organic molecules are included. The network is complete up to H6C2N2O3. STAND2015 is successfully tested against atmospheric chemistry models for HD 209458b, Jupiter, and the present-day Earth using a simple one- dimensionalphotochemistry/diffusion code. Our results for the early Earth agree with those of Kasting for CO2,H2, CO, and O2, but do not agree for water and atomic oxygen. We use the network to simulate an experiment where varied chemical initial conditions are irradiated by UV light. The result from our simulation is that more glycine is produced when more ammonia and methane is present. -
Gas Phase Formation of C-Sic3 Molecules in the Circumstellar Envelope of Carbon Stars
Gas phase formation of c-SiC3 molecules in the circumstellar envelope of carbon stars Tao Yanga,b,1,2, Luke Bertelsc,1, Beni B. Dangib,3, Xiaohu Lid,e, Martin Head-Gordonc,2, and Ralf I. Kaiserb,2 aState Key Laboratory of Precision Spectroscopy, East China Normal University, Shanghai 200062, P. R. China; bDepartment of Chemistry, University of Hawai‘iatManoa, Honolulu, HI 96822; cDepartment of Chemistry, University of California, Berkeley, CA 94720; dXinjiang Astronomical Observatory, Chinese Academy of Sciences, Urumqi, Xinjiang 830011, P. R. China; and eNational Astronomical Observatories, Chinese Academy of Sciences, Beijing 100012, P. R. China Contributed by Martin Head-Gordon, May 17, 2019 (sent for review July 20, 2018; reviewed by Piergiorgio Casavecchia and David Clary) Complex organosilicon molecules are ubiquitous in the circumstel- Modern astrochemical models propose that the very first lar envelope of the asymptotic giant branch (AGB) star IRC+10216, silicon–carbon bonds are formed in the inner envelope of the but their formation mechanisms have remained largely elusive until carbon star, which is undergoing mass loss at the rates of several − now. These processes are of fundamental importance in initiating a 10 5 solar masses per year (22, 23). Pulsations from the central chain of chemical reactions leading eventually to the formation of star may initiate shocks, which (photo)fragment the circumstellar — organosilicon molecules among them key precursors to silicon car- materials (24, 25). These nonequilibrium conditions cause tem- — bide grains in the circumstellar shell contributing critically to the peratures of 3,500 K or above (19) and lead to highly reactive galactic carbon and silicon budgets with up to 80% of the ejected metastable fragments such as electronically excited silicon atoms, materials infused into the interstellar medium. -
Periodic Trends Lab CHM120 1The Periodic Table Is One of the Useful
Periodic Trends Lab CHM120 1The Periodic Table is one of the useful tools in chemistry. The table was developed around 1869 by Dimitri Mendeleev in Russia and Lothar Meyer in Germany. Both used the chemical and physical properties of the elements and their tables were very similar. In vertical groups of elements known as families we find elements that have the same number of valence electrons such as the Alkali Metals, the Alkaline Earth Metals, the Noble Gases, and the Halogens. 2Metals conduct electricity extremely well. Many solids, however, conduct electricity somewhat, but nowhere near as well as metals, which is why such materials are called semiconductors. Two examples of semiconductors are silicon and germanium, which lie immediately below carbon in the periodic table. Like carbon, each of these elements has four valence electrons, just the right number to satisfy the octet rule by forming single covalent bonds with four neighbors. Hence, silicon and germanium, as well as the gray form of tin, crystallize with the same infinite network of covalent bonds as diamond. 3The band gap is an intrinsic property of all solids. The following image should serve as good springboard into the discussion of band gaps. This is an atomic view of the bonding inside a solid (in this image, a metal). As we can see, each of the atoms has its own given number of energy levels, or the rings around the nuclei of each of the atoms. These energy levels are positions that electrons can occupy in an atom. In any solid, there are a vast number of atoms, and hence, a vast number of energy levels. -
Most Common Substances in Chemicals for Different Industries
Table 14 Most common substances by industry Figures for 2009. Substances contained in more than 10 products. A substance can be omitted for secrecy reasons. Industry CAS-no Substance Number of products A01 Agriculture 7732-18-5 Water 458 6484-52-2 Nitric acid ammonium salt 77 57-55-6 1,2-Propanediol 75 64742-65-0 Distillates (petroleum), solvent-dewaxed heavy 74 paraffinic 63148-62-9 Siloxanes and Silicones, di-Me 60 57-13-6 Urea 54 67-63-0 2-Propanol 54 11138-66-2 Xanthan gum 53 7783-20-2 Sulfuric acid diammonium salt 53 7722-76-1 Phosphoric acid, monoammonium salt 52 7487-88-9 Sulfuric acid magnesium salt (1:1) 51 7447-40-7 Potassium chloride 46 56-81-5 1,2,3-Propanetriol 44 7778-80-5 Sulfuric acid dipotassium salt 43 1310-73-2 Sodium hydroxide 41 7647-14-5 Sodium chloride 41 2634-33-5 1,2-Benzisothiazol-3(2H)-one 38 1310-58-3 Potassium hydroxide 33 7757-79-1 Nitric acid potassium salt 33 7785-87-7 Manganese sulfate 32 7664-38-2 Phosphoric acid 32 72623-87-1 Lubricating oils, petroleum, C20-50, 31 hydrotreated neutral oil-based 64741-89-5 Distillates (petroleum), solvent-refined light 29 paraffinic 77-92-9 1,2,3-Propanetricarboxylic acid, 2-hydroxy- 28 8061-51-6 Lignosulfonic acid, sodium salt 28 7778-18-9 Sulfuric acid, calcium salt (1:1) 27 64-17-5 Ethanol 27 14807-96-6 Talc 26 64742-94-5 Solvent naphtha (petroleum), heavy arom. 25 68649-42-3 Phosphorodithioic acid, O,O-di-C1-14-alkyl 24 esters, zinc salts (2:1) 64-02-8 Glycine, N,N'-1,2-ethanediylbis[N- 24 (carboxymethyl)-, tetrasodium salt 64-19-7 Acetic acid 23 99-76-3 Benzoic acid, -
Product Detection of the CH Radical Reactions with Ammonia and Methyl-Substituted Amines Jérémy Bourgalais, Kacee L
Product Detection of the CH Radical Reactions with Ammonia and Methyl-Substituted Amines Jérémy Bourgalais, Kacee L. Caster, Olivier Durif, David L. Osborn, Sébastien D. Le Picard, Fabien Goulay To cite this version: Jérémy Bourgalais, Kacee L. Caster, Olivier Durif, David L. Osborn, Sébastien D. Le Picard, et al.. Product Detection of the CH Radical Reactions with Ammonia and Methyl-Substituted Amines. Journal of Physical Chemistry A, American Chemical Society, 2019, 123 (11), pp.2178-2193. 10.1021/acs.jpca.8b11688. hal-02089225 HAL Id: hal-02089225 https://hal-univ-rennes1.archives-ouvertes.fr/hal-02089225 Submitted on 11 Apr 2019 HAL is a multi-disciplinary open access L’archive ouverte pluridisciplinaire HAL, est archive for the deposit and dissemination of sci- destinée au dépôt et à la diffusion de documents entific research documents, whether they are pub- scientifiques de niveau recherche, publiés ou non, lished or not. The documents may come from émanant des établissements d’enseignement et de teaching and research institutions in France or recherche français ou étrangers, des laboratoires abroad, or from public or private research centers. publics ou privés. Page 1 of 47 The Journal of Physical Chemistry 1 2 3 Product Detection of the CH Radical Reactions with Ammonia and 4 5 6 Methyl-Substituted Amines 7 8 1 2 3 4 9 Jeremy Bourgalais, Kacee L. Caster, Olivier Durif, David L. Osborn, Sebastien D. Le 10 11 Picard,3 and Fabien Goulay2,* 12 13 1 LATMOS/IPSL, UVSQ Université Paris-Saclay, Sorbonne Université, CNRS, Guyancourt, 14 -
Reaction Pathways Linking Chemisorption to Desorption of Methylchlorosilanes on Copper(001)
REACTION PATHWAYS LINKING CHEMISORPTION TO DESORPTION OF METHYLCHLOROSILANES ON COPPER(001) BY JAMES LALLO A dissertation submitted to the Graduate School|New Brunswick Rutgers, The State University of New Jersey in partial fulfillment of the requirements for the degree of Doctor of Philosophy Graduate Program in Chemistry and Chemical Biology Written under the direction of Professor B.J. Hinch and approved by New Brunswick, New Jersey October, 2012 ABSTRACT OF THE DISSERTATION Reaction pathways linking chemisorption to desorption of methylchlorosilanes on copper(001) by James Lallo Dissertation Director: Professor B.J. Hinch The interactions of silane molecules with metal surfaces are pivotal in many com- mercial processes. Of particular interest is the commercial \Direct Process," in which methyl chloride (CH3Cl) is exposed to silicon, in the presence of a copper catalyst and other promoters, producing dimethyldichlorosilane as the predominant product. Previous UHV studies have investigated the interaction of \pre-dissociated" methyl (CH3) and chlorine (Cl) with copper and copper-silicide surfaces. This thesis investi- gates the reaction mechanisms of \pre-associated" methylchlorosilanes ((CH3)xClySiHz, x+y+z=4) adsorbed on a copper(001) surface. The goal was to develop an understand- ing of the intermediates and transfer processes involved for dissociative adsorption and subsequent desorption of these molecules. Only molecules containing at least one Si- H bond were observed to undergo chemisorption. It was found that dimethylsilane (CH3)2SiH2 and methylsilane (CH3)SiH3 exhibit ligand transfer on the copper sur- face, leading to the desorption of trimethylsilane (CH3)3SiH, in both cases. The sug- gested intermediates present after adsorption of methylsilane were methylsilyl CH3SiH2, methysilylene CH3SiH and methylsilylidyne CH3Si. -
Aromatic Formation Promoted by Ion-Driven Radical Pathways In
Aromatic Formation Promoted by Ion-Driven Radical Pathways in EUV Photochemical Experiments Simulating Titan’s Atmospheric Chemistry Jérémy Bourgalais, Nathalie Carrasco, Ludovic Vettier, Antoine Comby, Dominique Descamps, Stephane Petit, Valérie Blanchet, Jerôme Gaudin, Yann Mairesse, Bernard Marty To cite this version: Jérémy Bourgalais, Nathalie Carrasco, Ludovic Vettier, Antoine Comby, Dominique Descamps, et al.. Aromatic Formation Promoted by Ion-Driven Radical Pathways in EUV Photochemical Experiments Simulating Titan’s Atmospheric Chemistry. Journal of Physical Chemistry A, American Chemical Society, 2021, 125 (15), pp.3159-3168. 10.1021/acs.jpca.1c00324. insu-03201041 HAL Id: insu-03201041 https://hal-insu.archives-ouvertes.fr/insu-03201041 Submitted on 18 May 2021 HAL is a multi-disciplinary open access L’archive ouverte pluridisciplinaire HAL, est archive for the deposit and dissemination of sci- destinée au dépôt et à la diffusion de documents entific research documents, whether they are pub- scientifiques de niveau recherche, publiés ou non, lished or not. The documents may come from émanant des établissements d’enseignement et de teaching and research institutions in France or recherche français ou étrangers, des laboratoires abroad, or from public or private research centers. publics ou privés. Aromatic Formation Promoted by Ion-Driven Radical Pathways in EUV Photochemical Experiments Simulating Titan's Atmospheric Chemistry J´er´emyBourgalais,∗,y,z,k Nathalie Carrasco,y Ludovic Vettier,y Antoine Comby,{ Dominique Descamps,{