Chemical Engineering
Total Page:16
File Type:pdf, Size:1020Kb
Load more
Recommended publications
-
Growth and Characterization of Lif Single-Crystal Fibers by the Micro
ARTICLE IN PRESS Journal of Crystal Growth 270 (2004) 121–123 Growth and characterization of LiF single-crystal fibers by the micro-pulling-down method A.M.E. Santoa, B.M. Epelbaumb, S.P. Moratoc, N.D. Vieira Jr.a, S.L. Baldochia,* a Instituto de Pesquisas Energeticas! e Nucleares, IPEN-CNEN/SP, Av. Prof. Lineu Prestes, CEP 05508-900, Sao* Paulo, SP, Brazil b Department of Materials Science, University of Erlangen-Nurnberg, D-91058, Erlangen, Germany c LaserTools Tecnologia Ltda., 05379-130,Sao* Paulo, SP, Brazil Accepted 27 May 2004 Available online 20 July 2004 Communicated by G. Muller. Abstract Good optical quality LiF single-crystalline fibers ranging from 0:5to0:8 mm in diameter and 100 mm in length were successfully grown by the micro-pulling-down technique in the resistive mode. A commercial equipment was modified in order to achieve suitable conditions to grow fluoride single-crystalline fibers. r 2004 Elsevier B.V. All rights reserved. PACS: 81.10.Fq; 78.20.Àe Keywords: A2. Micro-pulling-down method; A2. Single crystal growth; B1. Fluorides 1. Introduction oxide single-crystals have already been grown by the laser heated pedestal growth (LHPG) [2] and There is an increasinginterest in the production by the micro-pulling-down (m-PD) [3] methods. of single-crystalline fibers. Their unique properties However, the growth and hence the possible indicate their use for production of a variety of applications of fluoride single-crystalline fibers optical and electronic devices [1]. The final shape has not yet been investigated. of the single-crystalline fiber is already in a form As it is already known from other methods of suitable for optical testingand applications, fluoride growth, these materials are very sensitive reducingthe time and cost of preparation. -
Hafnium Review Awaiting the Nuclear Renaissance
Monday, August 17, 2020 Hallgarten & Company Sector Review Christopher Ecclestone [email protected] Hafnium Review Awaiting the Nuclear Renaissance The Hafnium Wannabes Strategy Ticker Market Cap Project Country Developers Australian Strategic Materials Hold ASM.ax AUD$128mn Dubbo Australia Leading Edge Hold LEM.v CAD$21.9mn Norra Karr Sweden Search Minerals Avoid SMY.v CAD$9.3mn Foxtrot Canada Texas Mineral Resources Avoid TMRC US$123mn Round Top USA Hallgarten & Company (44) 795 08 53 621 Monday, August 17, 2020 Hafnium Review Awaiting the Nuclear Renaissance + Hafnium (Hf) has become a metal that is discussed more often, principally as a by-product credit by developers of Rare Earth deposits where it appears as an accessory mineral + Hf is joined at the hip with Zirconium and there is little prospect of developing one without the other, fortunately there is good demand for Zr at current times + The burgeoning construction of nuclear power stations in China promises stronger demand for Hf from its uses in such facilities + The production of HF is currently dominated by the US and France, with China having limited influence (thus far) The Hafnium price has been bouncing along the bottom for years with little sign of recuperation on the horizon Two projects that have cited Hafnium resources, DZP and Silver Fox, are burdened by massive capex (the former) and little prospect of getting to production (the latter) Financing of projects remains very difficult and almost inevitably requires a committed offtaker The Highest of High Tech Usages The metal we shall look at here is obscure even compared to others we have covered in recent times. -
Inorganic Chemistry for Dummies® Published by John Wiley & Sons, Inc
Inorganic Chemistry Inorganic Chemistry by Michael L. Matson and Alvin W. Orbaek Inorganic Chemistry For Dummies® Published by John Wiley & Sons, Inc. 111 River St. Hoboken, NJ 07030-5774 www.wiley.com Copyright © 2013 by John Wiley & Sons, Inc., Hoboken, New Jersey Published by John Wiley & Sons, Inc., Hoboken, New Jersey Published simultaneously in Canada No part of this publication may be reproduced, stored in a retrieval system or transmitted in any form or by any means, electronic, mechanical, photocopying, recording, scanning or otherwise, except as permitted under Sections 107 or 108 of the 1976 United States Copyright Act, without either the prior written permis- sion of the Publisher, or authorization through payment of the appropriate per-copy fee to the Copyright Clearance Center, 222 Rosewood Drive, Danvers, MA 01923, (978) 750-8400, fax (978) 646-8600. Requests to the Publisher for permission should be addressed to the Permissions Department, John Wiley & Sons, Inc., 111 River Street, Hoboken, NJ 07030, (201) 748-6011, fax (201) 748-6008, or online at http://www.wiley. com/go/permissions. Trademarks: Wiley, the Wiley logo, For Dummies, the Dummies Man logo, A Reference for the Rest of Us!, The Dummies Way, Dummies Daily, The Fun and Easy Way, Dummies.com, Making Everything Easier, and related trade dress are trademarks or registered trademarks of John Wiley & Sons, Inc. and/or its affiliates in the United States and other countries, and may not be used without written permission. All other trade- marks are the property of their respective owners. John Wiley & Sons, Inc., is not associated with any product or vendor mentioned in this book. -
Repair of Pressure Equipment and Piping
ASME PCC-2–2018 (Revision of ASME PCC-2-2015) Repair of Pressure Equipment and Piping AN AMERICAN NATIONAL STANDARD Provided by IHS Markit under license with ASME ASME PCC-2–2018 (Revision of ASME PCC-2–2015) Repair of Pressure Equipment and Piping AN AMERICAN NATIONAL STANDARD Two Park Avenue • New York, NY • 10016 USA x Provided by IHS Markit under license with ASME Date of Issuance: December 31, 2018 The next edition of this Standard is scheduled for publication in 2022. ASME issues written replies to inquiries concerning interpretations of technical aspects of this Standard. Periodically certain actions of the ASME PCC Committees may be published as Cases. Cases and interpretations are published on the ASME website under the Committee Pages at http://cstools.asme.org/ as they are issued. Errata to codes and standards may be posted on the ASME website under the Committee Pages to provide corrections to incorrectly published items, or to correct typographical or grammatical errors in codes and standards. Such errata shall be used on the date posted. The Committee Pages can be found at http://cstools.asme.org/. There is an option available to automatically receive an e-mail notification when errata are posted to a particular code or standard. This option can be found on the appropriate Committee Page after selecting “Errata” in the “Publication Information” section. ASME is the registered trademark of The American Society of Mechanical Engineers. This code or standard was developed under procedures accredited as meeting the criteria for American National Standards. The Standards Committee that approved the code or standard was balanced to assure that individuals from competent and concerned interests have had an opportunity to participate. -
8402Ba D6745675513242bdb4
General principles of extraction of metals (i) Crushing and pulverization (ii) Concentration or dressing of the ore (iii) Calcination or roasting of the ore (iv) Reduction of metal oxides to free metal (v) Purification and refining of metal. Crushing and Pulverization The ore is generally obtained as big rock pieces. These big lumps of the ore are crushed to smaller pieces by using jaw-crushers and grinders. One of the plates of the crusher is stationary while the other moves to and fro and the crushed pieces are collected below The crushed pieces of the ore are then pulverized (powdered) in a stamp mill Concentration or Dressing of the Ore Generally, the ores are found mixed with earthy impurities like sand, clay, lime stone etc. These unwanted impurities in the ore are called gangue or matrix. The process of removal of gangue from powdered ore is called concentration or ore dressing. several methods for concentrating the ores. The choice of method depends on the nature of the ore. (i) Gravity separation (Hydraulic washing): concentration of heavier oxide ores, like haematite (Fe2O3) tinstone (SnO2) and gold (Au). (ii) Magnetic separation method: Those ores can be concentrated which either contain impurities which are magnetic or are themselves magnetic in nature. For example, the tin ore, tin stone (SnO2 ) itself is non-magnetic but contains magnetic impurities such as iron tungstate (FeWO4 ) and manganese tungstate (MnWO4 ) . (iii) Froth floatation method This method is especially applied to sulphide ores, such as galena (PbS), zinc blende (ZnS), or copper pyrites (CuFeS2 ). It is based on the different wetting properties of the surface of the ore and gangue particles. -
Quantification of Hafnium in Selected Inorganic and Organometallic Compounds
Quantification of hafnium in selected inorganic and organometallic compounds A dissertation submitted to meet the requirements for the degree of Magister Scientiae in the FACULTY OF NATURAL AND AGRICULTURAL SCIENCES DEPARTMENT OF CHEMISTRY at the UNIVERSITY OF THE FREE STATE BLOEMFONTEIN by GONTSE ATLHOLANG ADELINE MALEFO Supervisor Prof. W. Purcell Co-supervisors Dr. J.T. Nel and Dr. M Nete February 2016 Declaration I declare that the thesis entitled “THE QUANTIFICATION OF HAFNIUM IN SELECTED INORGANIC AND ORGANOMETALLIC COMPOUNDS” submitted for the degree Magister in Analytical Chemistry, at the University of the Free State is my own original work and has not been previously submitted to any other institution of higher education in the Republic of South Africa or abroad. I further declare that all sources cited or quoted are indicated and acknowledged by means of a comprehensive list of references. Signature………………………………… Date…………………..…………. Gontse Atlholang Adeline Malefo Acknowledgements I would like to thank and express my sincere gratitude to; My Lord and saviour, Jesus Christ for his grace, divine guidance and all the strength bestowed upon me throughout the research project. My supervisor, Prof. W. Purcell for his guidance and patient support throughout the research project. His expertise and understanding contributed greatly to my knowledge in the field of study. My co-supervisor, Dr. Nel, for his valuable contributions in assisting with reviews of each chapter which greatly improved/enhanced the content my thesis. My co-supervisor, Dr. M. Nete, for his continuous encouragement and support. He was very helpful to the completion of this study. Analytical chemistry group (Deidre, Dika, Hlengiwe, Enerstine, Melaku, Ntoi, Sibongile, Sumit, Trevor and Qinisile) for providing a conducive work environment. -
Metal Prices in the United States Through 2010
Metal Prices in the United States Through 2010 Aluminum Germanium Mercury Silver Antimony Gold Molybdenum Tantalum Arsenic Hafnium Nickel Tellurium Beryllium Indium Niobium Thallium Bismuth Iron and Steel Platinum-Group Metals Tin Cadmium Iron and Steel Scrap Rare-Earth Metals Titanium Cesium Iron Ore Rhenium Tungsten Chromium Lead Rubidium Vanadium Cobalt Lithium Selenium Zinc Copper Magnesium Silicon Zirconium Gallium Manganese 1970 1975 1980 1985 1990 1995 2000 2005 2010 Scientific Investigations Report 2012–5188 U.S. Department of the Interior U.S. Geological Survey Metal Prices in the United States Through 2010 By U.S. Geological Survey National Minerals Information Center staff Scientific Investigations Report 2012–5188 U.S. Department of the Interior U.S. Geological Survey U.S. Department of the Interior KEN SALAZAR, Secretary U.S. Geological Survey Marcia K. McNutt, Director U.S. Geological Survey, Reston, Virginia: 2013 For more information on the USGS—the Federal source for science about the Earth, its natural and living resources, natural hazards, and the environment, visit http://www.usgs.gov or call 1–888–ASK–USGS. For an overview of USGS information products, including maps, imagery, and publications, visit http://www.usgs.gov/pubprod To order this and other USGS information products, visit http://store.usgs.gov Any use of trade, firm, or product names is for descriptive purposes only and does not imply endorsement by the U.S. Government. Although this information product, for the most part, is in the public domain, it also may contain copyrighted materials as noted in the text. Permission to reproduce copyrighted items must be secured from the copyright owner. -
Laser Floating Zone Growth: Overview, Singular Materials, Broad Applications, and Future Perspectives
crystals Review Laser Floating Zone Growth: Overview, Singular Materials, Broad Applications, and Future Perspectives Francisco Rey-García 1,* , Rafael Ibáñez 2, Luis Alberto Angurel 1 , Florinda M. Costa 3 and Germán F. de la Fuente 1,* 1 Instituto de Nanociencia y Materiales de Aragón (CSIC-Universidad de Zaragoza), María de Luna 3, E-50018 Zaragoza, Spain; [email protected] 2 Institut de Ciència dels Materials de la Universitat de Valéncia, C/ Catedrático José Beltrán, 2, E-46980 Paterna, Spain; [email protected] 3 Departamento de Física & i3N, Campus de Santiago s/n, Universidade de Aveiro, PT-3810-193 Aveiro, Portugal; fl[email protected] * Correspondence: [email protected] (F.R.-G.); [email protected] (G.F.d.l.F.) Abstract: The Laser Floating Zone (LFZ) technique, also known as Laser-Heated Pedestal Growth (LHPG), has been developed throughout the last several decades as a simple, fast, and crucible-free method for growing high-crystalline-quality materials, particularly when compared to the more conventional Verneuil, Bridgman–Stockbarger, and Czochralski methods. Multiple worldwide efforts have, over the years, enabled the growth of highly oriented polycrystalline and single-crystal high- melting materials. This work attempted to critically review the most representative advancements in LFZ apparatus and experimental parameters that enable the growth of high-quality polycrystalline materials and single crystals, along with the most commonly produced materials and their relevant physical properties. Emphasis will be given to materials for photonics and optics, as well as for electrical applications, particularly superconducting and thermoelectric materials, and to the growth of metastable phases. -
Summaries of Physical Research in Metallurgy, Solid State Physics, and Ceramics
TID-4005(Pt. 1, 5th Ed.) METALLURGY AND CERAMICS SUMMARIES OF PHYSICAL RESEARCH IN METALLURGY, SOLID STATE PHYSICS, AND CERAMICS Edited by Ralph R. Nash July 1959 [TIS Issuance Date] Division of Research, AEC Washington, D. C. 20,~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~"~""·nt~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~.:::; *~~~~~~~~~~~~~~~~~Vr~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~iii::i::lll::l:::~ ~ , ~ ~ ~ ~ ~ ~ ~ """"""" V-160"r-4411!.A!MCI~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~r:::ii::::i::::iii~ii: ..O'. UNITED STATES ATOMIC ENERGYrCOMMISSION Technical Information Service ..................... ::iiu;;ii:::::~:i ;::::::iif ·· · UNITEDSTATESATOMC ENERGY COMMISSION~~~~~~~~~~~~~ieiiijjjiiisliilii:iiilii ·· I TechnicalService~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~···,r::,·.Information UNITED STATES .ATOMIC ENERGY COMMISSION Technical Information Service LEGAL NOTICE the United This report was prepared as an account of Government sponsored work. Neither States, nor the Commission, nor any person acting on behalf of the Commission: to the accu- A. Makes any warranty or representation, expressed or implied, with respect or that the use racy, completeness, or usefulness of the information contained in this report, may not infringe of any Information, apparatus, method, or process disclosed in this report privately owned rights; or from the B. Assumes any liabilities with respect to the use of, or for damages resulting use of any information, apparatus, method, or process disclosed in this report. any em- As used in the above, "person acting on behalf of the Commission" includes the extent that ployee or contractor of the Commission, or employee of such contractor, to prepares, such employee or contractor of the Commission, or employee of such contractor or contract disseminates, or provides access to, any information pursuant to his employment with the Commission, or his employment with such contractor. This report has been reproduced directly from the best available copy. -
Fiber Crystal Growth of Cerium Doped Calcium Scandate, Strontium Yttrium Oxide, and Tristrontium Silicate
Fiber crystal growth of cerium doped calcium scandate, strontium yttrium oxide, and tristrontium silicate vorgelegt von Diplom-Mineraloge Jan Philippen Hilden von der Fakult¨at II - Mathematik und Naturwissenschaften der Technischen Universit¨at Berlin zur Erlangung des akademischen Grades Doktor der Naturwissenschaften Dr.rer.nat. genehmigte Dissertation Promotionsausschuss Vorsitzender: Prof. Dr. Peter Strasser Berichter: Prof. Dr. Martin Lerch Berichter: PD Dr. habil. Detlef Klimm Tag der wissenschaftlichen Aussprache: 24.09.2013 Berlin 2013 D83 Abstract An experimental approach to three new materials crystallized with laser-heated pedestal growth and micro-pulling-down method is given. Calcium scandate, stron- tium yttrium oxide, and tristrontium silicate are related high-melting oxides, which have been investigated as light phosphors in the last decade. In this work cerium doped single crystalline fibers are fabricated. Their luminescence properties and pos- sible application as laser materials are investigated. Differences between both fiber growth techniques are revealed with respect to the mass flow and steady state con- ditions. Phase relations are determined by thermal analysis and X-ray diffraction. They provide boundary conditions for the growth experiments and reveal the hith- erto unknown phase system calcium oxide–scandium oxide. Thermodynamic equi- librium calculation of the growth conditions gives further information on suitable growth parameters. Calculated fugacities of evaporating species are confirmed by high-temperature mass spectrometry, inductively coupled plasma optical emission spectrometry, and energy-dispersive X-ray spectroscopy. The evaporation can be minimized by a reasonable choice of growth parameters and atmosphere. Moreover, the atmosphere influences the cerium valence. This dependency is thermodynam- ically calculated and experimentally demonstrated by optical spectroscopy. -
Laser-Heated Pedestal Growth of Cerium Doped Calcium Scandate
Laser-heated pedestal growth of cerium doped calcium scandate crystal fibers J. Philippen∗, C. Guguschev, R. Bertram, D. Klimm Leibniz Institute for Crystal Growth, Max-Born-Str. 2, 12489 Berlin, Germany Abstract Ce3+ doped oxide materials are promising for optical emission in the green 3+ spectral range. The growth of CaSc2O4:Ce single crystals is reported here for the first time. Laser heated pedestal growth (LHPG) proved to be suitable for this refractive material, if performed in nitrogen of 99.999% purity. If the oxy- gen content of the growth atmosphere is substantially larger, Ce4+ is formed, which shows no useful optical emission. If the oxygen content is substantially lower, severe evaporation of calcium impedes stable crystal growth. Thermody- namic equilibrium calculations allowed to describe evaporation of species and cerium dopant charging under different growth conditions. The evaporation could be investigated by quadrupole mass spectrometry of emanating gases and by chemical analysis of fibers with ICP-OES. The congruent melting point was confirmed by DTA at 2110 degrees centigrade. Photoluminescence spectrome- try of fibers revealed the dependence of optical emission in the green spectral range on growth conditions. Keywords: A2. Laser heated pedestal growth, B1. Oxides, B2. Phosphors, B3. Solid state lasers arXiv:1212.2051v1 [cond-mat.mtrl-sci] 10 Dec 2012 ∗Corresponding author Email address: [email protected] (J. Philippen) Preprint submitted to Journal of Crystal Growth July 16, 2018 1. Introduction Among a vast variety of oxides that are used for light emission [1], Ce3+ doped materials are especially interesting because this ion shows broad green luminescence with a peak at 515 nm [2], if it is incorporated e.g. -
Nextsun Energy, Llc Safety and Health Program Manual
NextSunEnergy.com Solar Solutions For Generations D.P.U. 19-133 Attachment DPU-S-1(1) May 26, 2020 NEXTSUN ENERGY, LLC SAFETY AND HEALTH PROGRAM MANUAL NextSun Energy, LLC Workplace Safety & Health Process | Page 1 NEXTSUN ENERGY, LLC Safety & Health Processes Index PAGE Incident Prevention Plan 4-21 Aerial Lift Safety 22-29 Asbestos Awareness & Safety Process 30-48 Bloodborne Pathogens Exposure Control Plan 49-58 Chemicals 59-61 Confined Space Entry Process 62-63 Compressed Gas 64-75 Discipline in Support of Safety 76-84 Electrical Safety Process 85-96 Emergency Action Planning 97-104 Excavation & Trenching Safety Process 105-121 Fall Protection Process 122-138 Fire Protection Process 139-145 First Aid, CPR & Emergency Medical Response Process 146-155 Forklifts 156-162 Ground Fault Circuit Interrupters (GFCI) & Assured Grounding Process 163-168 Hydrogen Sulfide Safety Process 169-181 Hazard Communication Process 182-190 Hearing Conservation Process 191-198 Lead Safety & Compliance Process 199-232 Lifting and Carrying 233 Lockout/Tagout Process (LOTO) 234-253 Lifting/Mobile Equipment Process 254-267 Personal Protective Equipment Process 268-277 Process Safety Management Process 278-300 Respiratory Protection Process 301-331 Rigging/Hoisting 332-334 Scaffold Safety Process 335-345 Tools 346-353 Hot Work Welding, Burning & Cutting Process 354-372 NextSun Energy, LLC Workplace Safety & Health Process | Page 2 NEXTSUN ENERGY, LLC Incident Prevention Plan Index Section Safety Commitment Statement Authority & Accountability 1 Safety Director