Boron: from Fishing Rods to Flares Written by Tom Vulcan Friday, 10 June 2011
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An Introduction to Boron: History, Sources, Uses, and Chemistry William G
CORE Metadata, citation and similar papers at core.ac.uk Provided by PubMed Central An Introduction to Boron: History, Sources, Uses, and Chemistry William G. Woods Office of Environmental Health and Safety, University of California, Riverside, California Following a brief overview of the terrestrial distribution of boron in rocks, soil, and water, the history of the discovery, early utilization, and geologic origin of borate minerals is summmarized. Modern uses of borate-mineral concentrates, borax, boric acid, and other refined products include glass, fiberglass, washing products, alloys and metals, fertilizers, wood treatments, insecticides, and microbiocides. The chemistry of boron is reviewed from the point of view of its possible health effects. It is concluded that boron probably is complexed with hydroxylated species in biologic systems, and that inhibition and stimulation of enzyme and coenzymes are pivotal in its mode of action. - Environ Health Perspect 102(Suppl 7): 5-11 (1994) Key words: boron, borax, colemanite, glass, boric acid, health effects, enzyme, review Introduction retardants, as micronutrients in fertilizers were an important source of boric acid in Boron is an ubiquitous element in rocks, and for many other purposes, as well. Europe from about 1820 to the 1950s. soil, and water. Most of the earth's soils The varied chemistry and importance Borax also was made from Italian boric have <10 ppm boron, with high concen- of boron is dominated by the ability of acid in England, France, and Germany. trations found in parts of the western borates to form trigonal as well as tetrahe- The borate industry in Turkey com- United States and in other sites stretching dral bonding patterns and to create com- menced in 1865 with mining of the calci- from the Mediterranean to Kazakhstan. -
Effect of High Temperature on Wear Behavior of Stir Cast Aluminium
Mechanics and Mechanical Engineering Vol. 22, No. 4 (2018) 1031{1046 c Technical University of Lodz https://doi.org/10.2478/mme-2018-0082 Effect of High Temperature on Wear Behavior of Stir Cast Aluminium/Boron Carbide Composites X. Canute and M. C. Majumder Department of Mechanical Engineering, National Institute of Technology, Durgapur, India Received (9 May 2018) Revised (11 December 2018) Accepted (20 December 2018) The need for development of high temperature wear resistant composite materials with superior mechanical properties and tribological properties is increasing significantly. The high temperature wear properties of aluminium boron carbide composites was evaluated in this investigation. The effect of load, sliding velocity, temperature and reinforcement percentage on wear rate was determined by the pin heating method using pin heating arrangement. The size and structure of base alloy particles change considerably with an increase of boron carbide particles. The wettability and interface bonding between the matrix and reinforcement enhanced by the addition of potassium flurotitanate. ANOVA technique was used to study the effect of input parameters on wear rate. The investi- gation reveals that the load had higher significance than sliding velocity, temperature and weight fraction. The pin surface was studied with a high-resolution scanning elec- tron microscope. Regression analysis revealed an extensive association between control parameters and response. The developed composites can be used in the production of automobile parts requiring high wear, frictional and thermal resistance. Keywords: PCM, enhancement melting, eccentric cylinders, fins, LHS. 1. Introduction Metal matrix composites are widely preferred due to yield strength and wear re- sistance for high temperature applications [1]. -
Experiments on the Oxidation of Boron Carbide at High Temperatures
Forschungszentrum Karlsruhe in der Helmholtz-Gemeinschaft Wissenschaftliche Berichte FZKA 6979 Experiments on the Oxidation of Boron Carbide at High Temperatures M. Steinbrück, A. Meier, U. Stegmaier, L. Steinbock Institut für Materialforschung Programm Nukleare Sicherheitsforschung Mai 2004 Forschungszentrum Karlsruhe in der Helmholtz-Gemeinschaft Wissenschaftliche Berichte FZKA 6979 Experiments on the Oxidation of Boron Carbide at High Temperatures M. Steinbrück, A. Meier, U. Stegmaier, L. Steinbock Institut für Materialforschung Programm Nukleare Sicherheitsforschung Forschungszentrum Karlsruhe GmbH, Karlsruhe 2004 Impressum der Print-Ausgabe: Als Manuskript gedruckt Für diesen Bericht behalten wir uns alle Rechte vor Forschungszentrum Karlsruhe GmbH Postfach 3640, 76021 Karlsruhe Mitglied der Hermann von Helmholtz-Gemeinschaft Deutscher Forschungszentren (HGF) ISSN 0947-8620 urn:nbn:de:0005-069792 OXIDATION VON BORKARBID BEI HOHEN TEMPERATUREN ZUSAMMENFASSUNG Borkarbid wird weltweit in verschiedenen Kernreaktoren als Absorbermaterial in Steuer- stäben eingesetzt. Während eines hypothetischen schweren Störfalls führen eutektische Wechselwirkungen zwischen B4C und den umgebenden Hüllrohren aus rostfreiem Stahl schon bei Temperaturen um 1200 °C und somit weit unterhalb der Schmelztemperaturen der einzelnen Komponenten zur Bildung von Schmelzphasen. Das so freigelegte Absorber- material sowie gebildete B4C/Metall-Schmelzen sind dem Dampf im Reaktor ausgesetzt. Die Oxidation von Borkarbid ist stark exotherm und führt zur Bildung von gasförmigen -
Synthesis, Characterization and Energetic Performance
SYNTHESIS, CHARACTERIZATION AND ENERGETIC PERFORMANCE OF METAL BORIDE COMPOUNDS FOR INSENSITIVE ENERGETIC MATERIALS by Michael L. Whittaker A thesis submitted to the faculty of The University of Utah in partial fulfillment of the requirements for the degree of Master of Science Department of Materials Science and Engineering University of Utah May 2012 Copyright © Michael L. Whittaker 2012 All Rights Reserved The University of Utah Graduate School STATEMENT OF THESIS APPROVAL The thesis of Michael L. Whittaker has been approved by the following supervisory committee members: Raymond A. Cutler , Chair 03/09/2012 Date Approved Anil V. Virkar , Member 03/09/2012 Date Approved Gerald B. Stringfellow , Member 03/09/2012 Date Approved and by Feng Liu , Chair of the Department of Materials Science and Engineering and by Charles A. Wight, Dean of The Graduate School. ABSTRACT Six metal boride compounds (AlB2, MgB2, Al0.5Mg0.5B2, AlB12, AlMgB14 and SiB6) with particle sizes between 10-20 m were synthesized for insensitive energetic fuel additives from stoichiometric physical mixtures of elemental powders by high temperature solid state reaction. B4C was also investigated as a lower cost source of boron in AlB2 synthesis and showed promise as a boron substitute. Thermal analysis confirmed that the formation of boride compounds from physical mixtures decreased sensitivity to low temperature oxidation over the aluminum standard. Both Al+2B and AlB2 were much less sensitive to moisture degradation than aluminum in high humidity (10-100% relative humidity) and high temperature (20-80°C) environments. AlB2 was determined to be safe to store for extended periods of time in cool, dry environments. -
Boiler 26 SEARLES VALLEY MINERALS
SEARLES VALLEY MINERALS — TRONA, ARGUS and WESTEND FACILITY MDAQMD Federal Operating Permit Number: 90002 MOJAVE DESERT AIR QUALITY MANAGEMENT DISTRICT Federal Operating Permit Number: 90002 For: SEARLES VALLEY MINERALS OPERATIONS, INC. Facility: TRONA, ARGUS, AND WESTEND (FACILITIES) Renewed Pursuant to MDAQMD Regulation XII Effective Date: March 14, 2017 This Federal Operating Permit Expires On: March 14, 2022 Issued By: Br., Poiriez Executive Director 14306 PARK AVENUE, VICTORVILLE, CALIFORNIA 92392 PHONE (760) 245-1661 FAX (760) 245-2022 SEARLES VALLEY MINERALS – TRONA, ARGUS and WESTEND FACILITY MDAQMD Federal Operating Permit Number: 90002 PERMIT REVISIONS This Federal Operating Permit (FOP) is renewed pursuant to Regulation XII- Federal Operating Permits. See Statement of Legal and Factual Basis for a summary of items related to this FOP renewal and an explanation of pertinent applicability determinations made to this FOP during renewal. 2 SEARLES VALLEY MINERALS – TRONA, ARGUS and WESTEND FACILITY MDAQMD Federal Operating Permit Number: 90002 TABLE OF CONTENTS Page Permit Revisions ......................................................................................................2 Part I Introductory Information ...................................................................................... I-4 Part II Applicable Requirements and Emissions Limitations .........................................II-9 Part III Monitoring, Recordkeeping, Reporting and Testing Requirements ................ III-32 Part IV Standard Federal Operating -
Surface Properties and Morphology of Boron Carbide Nanopowders Obtained by Lyophilization of Saccharide Precursors
materials Article Surface Properties and Morphology of Boron Carbide Nanopowders Obtained by Lyophilization of Saccharide Precursors Dawid Kozie ´n 1,* , Piotr Jele ´n 1 , Joanna St˛epie´n 2 , Zbigniew Olejniczak 3 , Maciej Sitarz 1 and Zbigniew P˛edzich 1,* 1 Faculty of Materials Science and Ceramics, AGH University of Science and Technology, 30 Mickiewicz Av., 30-059 Kraków, Poland; [email protected] (P.J.); [email protected] (M.S.) 2 Academic Centre for Materials and Nanotechnology, AGH University of Science and Technology, 30 Mickiewicz Av., 30-059 Kraków, Poland; [email protected] 3 Institute of Nuclear Physics, 152 Radzikowskiego St., 31-342 Kraków, Poland; [email protected] * Correspondence: [email protected] (D.K.); [email protected] (Z.P.) Abstract: The powders of boron carbide are usually synthesized by the carbothermal reduction of boron oxide. As an alternative to high-temperature reactions, the development of the carbothermal reduction of organic precursors to produce B4C is receiving considerable interest. The aim of this work was to compare two methods of preparing different saccharide precursors mixed with boric acid with a molar ratio of boron to carbon of 1:9 for the synthesis of B4C. In the first method, aqueous ◦ ◦ solutions of saccharides and boric acid were dried overnight at 90 C and pyrolyzed at 850 C for 1 h under argon flow. In the second method, aqueous solutions of different saccharides and boric acid Citation: Kozie´n,D.; Jele´n,P.; were freeze-dried and prepared in the same way as in the first method. -
Ceramic Carbides: the Tough Guys of the Materials World
Ceramic Carbides: The Tough Guys of the Materials World by Paul Everitt and Ian Doggett, Technical Specialists, Goodfellow Ceramic and Glass Division c/o Goodfellow Corporation, Coraopolis, Pa. Silicon carbide (SiC) and boron carbide (B4C) are among the world’s hardest known materials and are used in a variety of demanding industrial applications, from blasting-equipment nozzles to space-based mirrors. But there is more to these “tough guys” of the materials world than hardness alone—these two ceramic carbides have a profile of properties that are valued in a wide range of applications and are worthy of consideration for new research and product design projects. Silicon Carbide Use of this high-density, high-strength material has evolved from mainly high-temperature applications to a host of engineering applications. Silicon carbide is characterized by: • High thermal conductivity • Low thermal expansion coefficient • Outstanding thermal shock resistance • Extreme hardness FIGURE 1: • Semiconductor properties Typical properties of silicon carbide • A refractive index greater than diamond (hot-pressed sheet) Chemical Resistance Although many people are familiar with the Acids, concentrated Good Acids, dilute Good general attributes of this advanced ceramic Alkalis Good-Poor (see Figure 1), an important and frequently Halogens Good-Poor overlooked consideration is that the properties Metals Fair of silicon carbide can be altered by varying the Electrical Properties final compaction method. These alterations can Dielectric constant 40 provide knowledgeable engineers with small Volume resistivity at 25°C (Ohm-cm) 103-105 adjustments in performance that can potentially make a significant difference in the functionality Mechanical Properties of a finished component. -
Views of the Borax Industry, Ca
http://oac.cdlib.org/findaid/ark:/13030/tf0n39n8j3 Online items available Views of the Borax Industry, ca. 1898-ca. 1915 Processed by Katherine Ruiz. The Bancroft Library, University of California, Berkeley Berkeley, California 94720-6000 1997 Views of the Borax Industry, ca. BANC PIC 1905.17174--PIC 1 1898-ca. 1915 Views of the Borax Industry, ca. 1898-ca. 1915 BANC PIC 1905.17174--PIC The Bancroft Library University of California Berkeley, California1997 Finding aid and digital representations of archival materials funded in part by a grant from the National Endowment for the Humanities. Processed and encoded by: California Heritage Digital Image Access Project staff in The Bancroft Library and The Library's Electronic Text Unit Digital images processed by: The Library Photographic Service Finding aid completed: December 1996 © 1997 The Regents of the University of California Collection Summary Collection Title: Views of the Borax Industry, Date: ca. 1898-ca. 1915 Collection Number: BANC PIC 1905.17174--PIC Creator: Pacific Coast Borax Company Extent: 49 photographic prints ; 20 x 25 cm.49 digital objects Repository: The Bancroft Library. University of California, Berkeley. Berkeley, California 94720-6000 Languages Represented: English Access Collection is available for use. Publication Rights Copyright has not been assigned to The Bancroft Library. All requests for permission to publish photographs must be submitted in writing to the Curator of Pictorial Collections. Permission for publication is given on behalf of The Bancroft Library as the owner of the physical items and is not intended to include or imply permission of the copyright holder, which must also be obtained by the reader. -
The Formation and Reactivity of I BORON CARBIDE and Related
University of Plymouth PEARL https://pearl.plymouth.ac.uk 04 University of Plymouth Research Theses 01 Research Theses Main Collection 1970 The Formation and Reactivity of BORON CARBIDE and related materials JONES, JAMES ALFRED http://hdl.handle.net/10026.1/1880 University of Plymouth All content in PEARL is protected by copyright law. Author manuscripts are made available in accordance with publisher policies. Please cite only the published version using the details provided on the item record or document. In the absence of an open licence (e.g. Creative Commons), permissions for further reuse of content should be sought from the publisher or author. The Formation and Reactivity of I BORON CARBIDE and related materials A Thesis presented for the Research Degree of DOCTOR OF PHILOSOPHY of the COUNCIL FOR NATIONAL ACADEMIC AWARDS London by JAMES ALFRED JONES Department of Chemistry Plymouth Polytechnic Plymouth, Devon- February^ 1970o F'.V flCCH. i'iC. 1 CLASS, T Shi LJl JoH 13' ABSTRACT 1 The formation of boron carbide, (CBC)*B^^0*^(3^0 is re• viewed with special reference to newer production methods and fabrication techniques. Its crystal structure and the nature of its bonding are discussed in relation to those of other borides and carbides. Information so far available on the sintering of this material is summarised in relation to its reactivity. Sintering into monolithic compoaentBcan only be achieved by hot pressing at pressures between 200 and 300 Kgcm'^ and at temperatures above 2000°C preferably at about 2,300^0 for the most rapid achievement of theoretical density, i.e. -
Processing of Reaction-Bonded B4C–Sic Composites in a Single-Mode Microwave Cavity
Available online at www.sciencedirect.com CERAMICS INTERNATIONAL Ceramics International 39 (2013) 1215–1219 www.elsevier.com/locate/ceramint Processing of reaction-bonded B4C–SiC composites in a single-mode microwave cavity Anthony Thuaulta,n, Sylvain Marinela,b, Etienne Savarya,c, Romain Heugueta, Se´bastien Saunierc, Dominique Goeuriotc, Dinesh Agrawalb aCRISMAT Laboratory UMR 6508 CNRS-ENSICAEN-UCBN, 6 Boulevard du Mare´chal Juin, 14050 Caen Cedex, France bMaterials Research Institute, Materials Research Laboratory Building, The Pennsylvania State University, University Park, PA 16802, USA cDe´partement Me´canique et Proce´de´s d’e´laboration, Centre des Sciences des Mate´riaux et des Structures, Ecole Nationale Supe´rieure des Mines de Saint- Etienne, 42023 Saint-Etienne Cedex 2, France Received 5 July 2012; received in revised form 16 July 2012; accepted 16 July 2012 Available online 24 July 2012 Abstract In this study, the reaction sintering of boron carbide, which consists in doing reactive infiltration of molten silicon throughout a porous sample made of B4C and carbon graphite was investigated. Thus, it has been shown that a single-mode microwave cavity can be successfully used to produce reaction-bonded B4C–SiC composite. A specific package, consisting of a SiC based susceptor and a boron nitride based insulating container, was used to heat up the B4C–Si system using a single-mode microwaves cavity under an Ar–H2 atmosphere. Pore-free B4C–SiC composite successfully produced consists of a mixture of B4C and polygonal shaped b-SiC within a residual silicon matrix. The indentation technique permits to determine mechanical properties of the samples which are compared to those obtained conventionally. -
Effect of Borate Addition on the Sintered Properties of Pulverised Fuel Ash E.A
Ceramics International 33 (2007) 993–999 www.elsevier.com/locate/ceramint Effect of borate addition on the sintered properties of pulverised fuel ash E.A. Uwe a, A.R. Boccaccini b, S.G. Cook c, C.R. Cheeseman a,* a Centre for Environmental Control and Waste Management, Department of Civil and Environmental Engineering, Imperial College London, SW7 2BU, UK b Department of Materials, Imperial College London, SW7 2BP, UK c Borax Europe Limited, 1A Guildford Business Park, Guildford GU2 8XG, UK Received 15 December 2005; received in revised form 8 January 2006; accepted 22 February 2006 Available online 25 April 2006 Abstract The effect of borate addition on the properties of sintered pulverised fuel ash (PFA) has been investigated. PFA from a major coal-fired power station in the UK has been formed into monolithic ceramic samples using dry powder compaction and sintering. Borax pentahydrate (Na2B4O7Á5H2O), anhydrous borax (Na2B4O7) and boric acid (H3BO3) were individually added to the PFA and the effects of firing between 1000 and 1200 8C have been investigated. Physical properties (density, water absorption and linear shrinkage), mechanical properties (bending strength and Vickers hardness), phase composition (X-ray diffraction) and sintered microstructure (scanning electron microscopy) are reported. Milling PFA containing 8% (by weight) of borax pentahydrate, to an average particle size of 7.25 mm and sintering at 1130 8C for 1 h, produces ceramics with properties comparable to those of commercial unglazed ceramic wall and floor tiles. The results indicate that PFA could be used to produce commercial ceramics using an economic manufacturing process, although current formulations display excessive shrinkage. -
14 Boron Element Pub 2020
Publication WSFNR-20-14C March 2020 BORON (B) – Tree Essential Element Dr. Kim D. Coder, Professor of Tree Biology & Health Care / University Hill Fellow University of Georgia Warnell School of Forestry & Natural Resources Boron (B) is a hard, brittle, brown, but light weight solid called a metalloid discovered in 1808. Its name is derived from Persian for a boron containing compound. The rest of its elemental family are all metals. It is never found in pure form. It is used for cleaning products, water softening, antiseptics, heat resistant glass, nuclear reactor rods, and transistors. In Trees Boron is a rare element and the lightest (except for hydrogen) element essential for trees. Boron is one of two essential elements (i.e. silicon is the other) usually present in a tree as a neutral molecule (undissociated form) rather than as an ion. The concentration of boron can vary widely in tissues. Its form in a tree depends upon tissue pH, existing as boric acid (B(OH)3 / H3BO3) where pH is less than 7.0 and the borate ion (B(OH)4-) where pH >7.5. Figure 1. At soil pH of 6.5 to 10.0, boron is poorly available or unavailable to trees. Boron performs one dominant role in trees as part of cell wall structure. Boron helps bind pectic polysaccharides in and between tree cell walls. Deficiency symptoms can quickly occur physiologically and structurally. Element Availability Problems Boron deficiency causes many biological and structural problems in trees. Boron can act as an antibiological agent in trees and when it is in short supply pathogens attacks are more effective and move quicker.