Use of Hydrofluosilicic Acid in Drinking Water Systems in The
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Vibrationally Excited Hydrogen Halides : a Bibliography On
VI NBS SPECIAL PUBLICATION 392 J U.S. DEPARTMENT OF COMMERCE / National Bureau of Standards National Bureau of Standards Bldg. Library, _ E-01 Admin. OCT 1 1981 191023 / oO Vibrationally Excited Hydrogen Halides: A Bibliography on Chemical Kinetics of Chemiexcitation and Energy Transfer Processes (1958 through 1973) QC 100 • 1X57 no. 2te c l !14 c '- — | NATIONAL BUREAU OF STANDARDS The National Bureau of Standards' was established by an act of Congress March 3, 1901. The Bureau's overall goal is to strengthen and advance the Nation's science and technology and facilitate their effective application for public benefit. To this end, the Bureau conducts research and provides: (1) a basis for the Nation's physical measurement system, (2) scientific and technological services for industry and government, (3) a technical basis for equity in trade, and (4) technical services to promote public safety. The Bureau consists of the Institute for Basic Standards, the Institute for Materials Research, the Institute for Applied Technology, the Institute for Computer Sciences and Technology, and the Office for Information Programs. THE INSTITUTE FOR BASIC STANDARDS provides the central basis within the United States of a complete and consistent system of physical measurement; coordinates that system with measurement systems of other nations; and furnishes essential services leading to accurate and uniform physical measurements throughout the Nation's scientific community, industry, and commerce. The Institute consists of a Center for Radiation Research, an Office of Meas- urement Services and the following divisions: Applied Mathematics — Electricity — Mechanics — Heat — Optical Physics — Nuclear Sciences" — Applied Radiation 2 — Quantum Electronics 1 — Electromagnetics 3 — Time 3 1 1 and Frequency — Laboratory Astrophysics — Cryogenics . -
United States Patent (10) Patent No.: US 7,190,052 B2 Lindgren (45) Date of Patent: Mar
US0071900.52B2 (12) United States Patent (10) Patent No.: US 7,190,052 B2 Lindgren (45) Date of Patent: Mar. 13, 2007 (54) SEMICONDUCTOR DEVICES WITH OXIDE 5,516,721 A 5/1996 Galli et al. COATINGS SELECTIVELY POSITONED 5,683,946 A 1 1/1997 Lu et al. OVER EXPOSED FEATURES INCLUDING 5,776,829 A 7/1998 Homma et al. SEMCONDUCTOR MATERAL 6,022,814 A 2/2000 Mikoshiba et al. 6,045,877 A 4/2000 Gleason et al. (75) Inventor: Joseph T. Lindgren, Boise, ID (US) 6,174,8246,130,116 AB1 10/20001/2001 MichaelSmith et etal. al. 6, 197,110 B1 3/2001 Lee et al. (73) Assignee: Micron Technology, Inc., Boise, ID 6,251,753 B1 6/2001 Yeh et al. (US) (*) Notice: Subject to any disclaimer, the term of this (Continued) patent is extended or adjusted under 35 OTHER PUBLICATIONS U.S.C. 154(b) by 0 days. Schreiber, S.J. et al., “Low Temperature Deposition of Microcrystal line Silicon For Thin Film Transistors,' CUED Electronic Devices (21) Appl. No.: 10/454.256 and Materials Group, http://www2.eng.cam.ac.uk/~www-edm/ (22) Filed: Jun. 3, 2003 projects/lowtempdepf1.htm, prior to Sep. 2000, 2 pages. e as (Continued) (65) Prior Publication Data Primary Examiner T. N. Quach US 2004/OO33682 A1 Feb. 19, 2004 (74) Attorney, Agent, or Firm TraskBritt Related U.S. Application Data (57) ABSTRACT (62) Division of application No. 10/218.268, filed on Aug. 13, 2002, now Pat. No. 6,593,221. A semiconductor device structure includes a passivation layer through which only non-silicon-comprising structures (51) Int. -
Study-Newcastle-Lonely-Planet.Pdf
Produced by Lonely Planet for Study NT NewcastleDO VIBRAne of Lonely Planet’s Top 10 Cities in Best in Travel 2011 N CREATIVE A LANET Y P ’S EL TO N P O 1 L 0 F TOP C O I T TOP E I E N S O 10 CITY I N 10 CITY ! 1 B 1 E 0 S 2 2011 T L I E N V T A R 2011 PLANE LY T’S NE T O O P L F 1 O 0 C E I N T I O E S ! 1 I 1 N 0 B 2 E L S E T V I A N R T LANET Y P ’S EL TO N P O 1 TOP L 0 F TOP C O I T 10 CITY E I E N S O 10 CITY I N ! 2011 1 B 1 E 0 LAN S P E 2 Y T 2011 T L L ’ I S E N E V T A R N T O O P L F 1 O 0 C E I N T I O E S ! 1 I 1 N 0 B 2 E L S E T V I A N R T E W RE HANI AKBAR st VER I » Age 22 from Saudi Arabia OL » From Saudi Arabia » Studying an International Foundation program What do you think of Newcastle? It’s so beautiful, not big not small, nice. It’s a good place for students who are studying, with a lot of nice people. -
Hydrofluoric Acid Reduction Project – TURI Grant 2017
Hydrofluoric Acid Reduction Project – TURI Grant 2017 Sponsored by: Toxics Use Reduction Institute 126 John St Lowell, MA 01854 TURI Report 2018-001 Authors: Tyler DeFosse David Demarey Supervisor: Paul Watson Special Thanks to: Joy Onasch – Toxics Use Reduction Institute John Raschko – Massachusetts Office of Technical Assistance and Technology 1 Table of Contents 1.0 Executive Summary .......................................................................................................................... 3 2.0 Background ....................................................................................................................................... 5 2.1 Introduction ......................................................................................................................................... 5 2.2 Literature Searches .......................................................................................................................... 6 2.2.1 Diffusion Dialysis ...................................................................................................................... 6 2.2.2 Reverse Osmosis ....................................................................................................................... 7 2.2.3 Hydrofluoric Acid Wastewater Recycling Method ............................................................... 7 2.2.4 Issues Regarding the Etching of Silicon Dioxide ................................................................. 8 2.3 Alternative Strategies ..................................................................................................................... -
UNITED STATES PATENT of FICE 2,640,086 PROCESS for SEPARATING HYDROGEN FLUORIDE from CHLORODFLUORO METHANE Robert H
Patented May 26, 1953 2,640,086 UNITED STATES PATENT of FICE 2,640,086 PROCESS FOR SEPARATING HYDROGEN FLUORIDE FROM CHLORODFLUORO METHANE Robert H. Baldwin, Chadds Ford, Pa., assignor to E. H. du Pont de Nemours and Company, Wi inington, Del, a corporation of Delaware No Drawing. Application December 15, 1951, Serial No. 261,929 9 Claims. (C. 260-653) 2 This invention relates to a process for Sep These objects are accomplished essentially by arating hydrogen fluoride from monochlorodi Subjecting a mixture of hydrogen fluoride and fluoronethane, and more particularly, separat Inonochlorodifluoromethane in the liquid phase ing these components from the reaction mixture to temperatures below 0° C., preferably at about obtained in the fluorination of chloroform with -30° C. to -50° C., at either atmospheric or hydrogen fluoride, Super-atmospheric pressures, together with from In the fluorination of chloroform in the prest about 0.25 mol to about 2.5 mols of chloroform ence Of a Catalyst, a reaction mixture is pro per mol of chlorodifluoronethane contained in duced which consists essentially of HCl, HF, the mixture and separating an upper layer rich CHCIF2, CHCl2F, CHCls, and CHF3. A method O in HF from a lower organic layer. The proceSS of Separating these components is disclosed in is operative with mixtures containing up to 77% U. S. Patent No. 2,450,414 which involves sep by weight of HF. arating the components by a special fractional It has been found that chloroform is substan distillation under appropriate temperatures and tially immiscible With EIF at temperatures be pressures. -
Appendix H EPA Hazardous Waste Law
Appendix H EPA Hazardous Waste Law This Appendix is intended to give you background information on hazardous waste laws and how they apply to you. For most U.S. Environmental Protection Agency (EPA) requirements that apply to the University, the Safety Department maintains compliance through internal inspections, record keeping and proper disposal. In Wisconsin, the Department of Natural Resources (DNR) has adopted the EPA regulations, consequently EPA and DNR regulations are nearly identical. EPA defines This Appendix only deals with "hazardous waste" as defined by the EPA. hazardous waste as Legally, EPA defines hazardous waste as certain hazardous chemical waste. This hazardous chemical Appendix does not address other types of regulated laboratory wastes, such as waste; radioactive, infectious, biological, radioactive or sharps. Chapter 8 descibes disposal procedures infectious and biohazardous waste for animals. Chapter 9 describes disposal procedures for sharps and other waste that are regulated by can puncture tissue. Chapter 11 discusses Radiation and the Radiation Safety for other agencies. Radiation Workers provides guidelines for the disposal of radioactive waste. Procedures for medical waste are written by the UW Hospital Safety Officer. The Office of Biological Safety can provide guidance for the disposal of infectious and biological waste. EPA regulations focus on industrial waste streams. As a result, many laboratory chemical wastes are not regulated by EPA as hazardous chemical waste. However, many unregulated chemical wastes do merit special handling and disposal If a waste can be procedures. Thus, Chapter 7 and Appendix A of this Guide recommend disposal defined as: procedures for many unregulated wastes as if they were EPA hazardous waste. -
Cylinder Valve Selection Quick Reference for Valve Abbreviations
SHERWOOD VALVE COMPRESSED GAS PRODUCTS Appendix Cylinder Valve Selection Quick Reference for Valve Abbreviations Use the Sherwood Cylinder Valve Series Abbreviation Chart on this page with the Sherwood Cylinder Valve Selection Charts found on pages 73–80. The Sherwood Cylinder Valve Selection Chart are for reference only and list: • The most commonly used gases • The Compressed Gas Association primary outlet to be used with each gas • The Sherwood valves designated for use with this gas • The Pressure Relief Device styles that are authorized by the DOT for use with these gases PLEASE NOTE: The Sherwood Cylinder Valve Selection Charts are partial lists extracted from the CGA V-1 and S-1.1 pamphlets. They can change without notice as the CGA V-1 and S-1.1 pamphlets are amended. Sherwood will issue periodic changes to the catalog. If there is any discrepancy or question between these lists and the CGA V-1 and S-1.1 pamphlets, the CGA V-1 and S-1.1 pamphlets take precedence. Sherwood Cylinder Valve Series Abbreviation Chart Abbreviation Sherwood Valve Series AVB Small Cylinder Acetylene Wrench-Operated Valves AVBHW Small Cylinder Acetylene Handwheel-Operated Valves AVMC Small Cylinder Acetylene Wrench-Operated Valves AVMCHW Small Cylinder Acetylene Handwheel-Operated Valves AVWB Small Cylinder Acetylene Wrench-Operated Valves — WB Style BV Hi/Lo Valves with Built-in Regulator DF* Alternative Energy Valves GRPV Residual Pressure Valves GV Large Cylinder Acetylene Valves GVT** Vertical Outlet Acetylene Valves KVAB Post Medical Valves KVMB Post Medical Valves NGV Industrial and Chrome-Plated Valves YVB† Vertical Outlet Oxygen Valves 1 * DF Valves can be used with all gases; however, the outlet will always be ⁄4"–18 NPT female. -
Fluorosilicic Acid CAS No
Product Safety Summary Fluorosilicic Acid CAS No. 16961-83-4 This Product Safety Summary is intended to provide a general overview of the chemical substance. The information in the summary is basic information and is not intended to provide emergency response information, medical information or treatment information. The summary should not be used to provide in-depth safety and health information. In-depth safety and health information can be found in the Safety Data Sheet (SDS) for the chemical substance. Names Fluorosilicic acid (FSA) Hexafluorosilicic acid (HFA or HFS) Sand acid Silicate(2-), hexafluoro- hydrogen (1:2) Silicofluoride Fluosilicic acid Hydroflurosilicic acid Silicofluoric acid Silicon hexafluoride dihydride Silicate(2-), hexafluoro-, dihydrogen Product Overview Solvay Fluorides, LLC does not sell fluorosilicic acid solutions directly to consumers. Most fluorosilicic acid is used in industrial or municipal applications/processes. Concentrated fluorosilicic acid solution (FSA) is used for water fluoridation, as a metal surface treatment and cleaner and for pH adjustment in industrial textile processing or laundries. It can also be used in the processing of hides, for hardening masonry and ceramics and in the manufacture of other chemicals. FSA can only exist as a liquid. There is no solid form. Fluorosilicic acid solutions are corrosive and contact can severely irritate and burn the skin and eyes causing possible permanent eye damage. Breathing concentrated fluorosilicic acid solutions can severely irritate and burn the nose, throat, and lungs, causing nosebleeds, cough, wheezing and shortness of breath. Many of the symptoms described are due to the hydrogen fluoride present as an impurity. Page 1 of 7 Copyright 2010-2013, Solvay America, Inc. -
Historical Group
Historical Group NEWSLETTER and SUMMARY OF PAPERS No. 64 Summer 2013 Registered Charity No. 207890 COMMITTEE Chairman: Prof A T Dronsfield | Prof J Betteridge (Twickenham, 4, Harpole Close, Swanwick, Derbyshire, | Middlesex) DE55 1EW | Dr N G Coley (Open University) [e-mail [email protected]] | Dr C J Cooksey (Watford, Secretary: Prof. J. W. Nicholson | Hertfordshire) School of Sport, Health and Applied Science, | Prof E Homburg (University of St Mary's University College, Waldegrave | Maastricht) Road, Twickenham, Middlesex, TW1 4SX | Prof F James (Royal Institution) [e-mail: [email protected]] | Dr D Leaback (Biolink Technology) Membership Prof W P Griffith | Dr P J T Morris (Science Museum) Secretary: Department of Chemistry, Imperial College, | Mr P N Reed (Steensbridge, South Kensington, London, SW7 2AZ | Herefordshire) [e-mail [email protected]] | Dr V Quirke (Oxford Brookes Treasurer: Dr J A Hudson | University) Graythwaite, Loweswater, Cockermouth, | Prof. H. Rzepa (Imperial College) Cumbria, CA13 0SU | Dr. A Sella (University College) [e-mail [email protected]] Newsletter Dr A Simmons Editor Epsom Lodge, La Grande Route de St Jean, St John, Jersey, JE3 4FL [e-mail [email protected]] Newsletter Dr G P Moss Production: School of Biological and Chemical Sciences, Queen Mary University of London, Mile End Road, London E1 4NS [e-mail [email protected]] http://www.chem.qmul.ac.uk/rschg/ http://www.rsc.org/membership/networking/interestgroups/historical/index.asp 1 RSC Historical Group Newsletter No. 64 Summer 2013 Contents From the Editor 2 Obituaries 3 Professor Colin Russell (1928-2013) Peter J.T. -
Alphabetical Index of Substances and Articles
ALPHABETICAL INDEX OF SUBSTANCES AND ARTICLES - 355 - NOTES TO THE INDEX 1. This index is an alphabetical list of the substances and articles which are listed in numerical order in the Dangerous Goods List in Chapter 3.2. 2. For the purpose of determining the alphabetical order the following information has been ignored even when it forms part of the proper shipping name: numbers; Greek letters; the abbreviations “sec” and “tert”; and the letters “N” (nitrogen), “n” (normal), “o” (ortho) “m” (meta), “p” (para) and “N.O.S.” (not otherwise specified). 3. The name of a substance or article in block capital letters indicates a proper shipping name. 4. The name of a substance or article in block capital letters followed by the word “see” indicates an alternative proper shipping name or part of a proper shipping name (except for PCBs). 5. An entry in lower case letters followed by the word “see” indicates that the entry is not a proper shipping name; it is a synonym. 6. Where an entry is partly in block capital letters and partly in lower case letters, the latter part is considered not to be part of the proper shipping name. 7. A proper shipping name may be used in the singular or plural, as appropriate, for the purposes of documentation and package marking. - 356 - INDEX Name and description Class UN No. Name and description Class UN No. Accumulators, electric, see 4.3 3292 Acid mixture, nitrating acid, see 8 1796 8 2794 8 2795 Acid mixture, spent, nitrating acid, see 8 1826 8 2800 8 3028 Acraldehyde, inhibited, see 6.1 1092 ACETAL 3 1088 -
Hexafluorosilicic Acid
Sodium Hexafluorosilicate [CASRN 16893-85-9] and Fluorosilicic Acid [CASRN 16961-83-4] Review of Toxicological Literature October 2001 Sodium Hexafluorosilicate [CASRN 16893-85-9] and Fluorosilicic Acid [CASRN 16961-83-4] Review of Toxicological Literature Prepared for Scott Masten, Ph.D. National Institute of Environmental Health Sciences P.O. Box 12233 Research Triangle Park, North Carolina 27709 Contract No. N01-ES-65402 Submitted by Karen E. Haneke, M.S. (Principal Investigator) Bonnie L. Carson, M.S. (Co-Principal Investigator) Integrated Laboratory Systems P.O. Box 13501 Research Triangle Park, North Carolina 27709 October 2001 Toxicological Summary for Sodium Hexafluorosilicate [16893-85-9] and Fluorosilicic Acid [16961-83-4] 10/01 Executive Summary Nomination Sodium hexafluorosilicate and fluorosilicic acid were nominated for toxicological testing based on their widespread use in water fluoridation and concerns that if they are not completely dissociated to silica and fluoride in water that persons drinking fluoridated water may be exposed to compounds that have not been thoroughly tested for toxicity. Nontoxicological Data Analysis and Physical-Chemical Properties Analytical methods for sodium hexafluorosilicate include the lead chlorofluoride method (for total fluorine) and an ion-specific electrode procedure. The percentage of fluorosilicic acid content for water supply service application can be determined by the specific-gravity method and the hydrogen titration method. The American Water Works Association (AWWA) has specified that fluorosilicic acid contain 20 to 30% active ingredient, a maximum of 1% hydrofluoric acid, a maximum of 200 mg/kg heavy metals (as lead), and no amounts of soluble mineral or organic substance capable of causing health effects. -
APPENDIX G Acid Dissociation Constants
harxxxxx_App-G.qxd 3/8/10 1:34 PM Page AP11 APPENDIX G Acid Dissociation Constants § ϭ 0.1 M 0 ؍ (Ionic strength ( † ‡ † Name Structure* pKa Ka pKa ϫ Ϫ5 Acetic acid CH3CO2H 4.756 1.75 10 4.56 (ethanoic acid) N ϩ H3 ϫ Ϫ3 Alanine CHCH3 2.344 (CO2H) 4.53 10 2.33 ϫ Ϫ10 9.868 (NH3) 1.36 10 9.71 CO2H ϩ Ϫ5 Aminobenzene NH3 4.601 2.51 ϫ 10 4.64 (aniline) ϪO SNϩ Ϫ4 4-Aminobenzenesulfonic acid 3 H3 3.232 5.86 ϫ 10 3.01 (sulfanilic acid) ϩ NH3 ϫ Ϫ3 2-Aminobenzoic acid 2.08 (CO2H) 8.3 10 2.01 ϫ Ϫ5 (anthranilic acid) 4.96 (NH3) 1.10 10 4.78 CO2H ϩ 2-Aminoethanethiol HSCH2CH2NH3 —— 8.21 (SH) (2-mercaptoethylamine) —— 10.73 (NH3) ϩ ϫ Ϫ10 2-Aminoethanol HOCH2CH2NH3 9.498 3.18 10 9.52 (ethanolamine) O H ϫ Ϫ5 4.70 (NH3) (20°) 2.0 10 4.74 2-Aminophenol Ϫ 9.97 (OH) (20°) 1.05 ϫ 10 10 9.87 ϩ NH3 ϩ ϫ Ϫ10 Ammonia NH4 9.245 5.69 10 9.26 N ϩ H3 N ϩ H2 ϫ Ϫ2 1.823 (CO2H) 1.50 10 2.03 CHCH CH CH NHC ϫ Ϫ9 Arginine 2 2 2 8.991 (NH3) 1.02 10 9.00 NH —— (NH2) —— (12.1) CO2H 2 O Ϫ 2.24 5.8 ϫ 10 3 2.15 Ϫ Arsenic acid HO As OH 6.96 1.10 ϫ 10 7 6.65 Ϫ (hydrogen arsenate) (11.50) 3.2 ϫ 10 12 (11.18) OH ϫ Ϫ10 Arsenious acid As(OH)3 9.29 5.1 10 9.14 (hydrogen arsenite) N ϩ O H3 Asparagine CHCH2CNH2 —— —— 2.16 (CO2H) —— —— 8.73 (NH3) CO2H *Each acid is written in its protonated form.