The Role of Calcium and Strontium As the Most Dominant Elements During
Total Page:16
File Type:pdf, Size:1020Kb
Load more
Recommended publications
-
Strontium-90
EPA Facts about Strontium-90 What is strontium-90? The most common isotope of strontium is strontium-90. Radioactive strontium-90 is produced when uranium and plutonium undergo fission. Fission The time required for a radioactive substance to is the process in which the nucleus of a lose 50 percent of its radioactivity by decay is radionuclide breaks into smaller parts. Large known as the half-life. Strontium-90 has a half- amounts of radioactive strontium-90 were life of 29 years and emits beta particles of produced during atmospheric nuclear weapons relatively low energy as it decays. Yttrium-90, its tests conducted in the 1950s and 1960s. As a decay product, has a shorter half-life (64 hours) result of atmospheric testing and radioactive than strontium-90, but it emits beta particles of fallout, this strontium was dispersed and higher energy. deposited on the earth. How are people exposed to strontium- 90? What are the uses of strontium-90? Although external exposure to strontium-90 Strontium-90 is used in medical and agricultural from nuclear testing is of minor concern because studies. It is also used in thermoelectric devices environmental concentrations are low, that are built into small power supplies for use strontium in the environment can become part of the food chain. This pathway of exposure in remote locations, such as navigational beacons, remote weather stations, and space became a concern in the 1950s with the advent vehicles. Additionally, strontium-90 is used in of atmospheric testing of nuclear explosives. electron tubes, radioluminescent markers, as a With the suspension of atmospheric testing of radiation source in industrial thickness gauges, nuclear weapons, dietary intake has steadily and for treatment of eye diseases. -
Comparison of Lead Calcium and Lead Selenium Alloys
A COMPARISON OF LEAD CALCIUM & LEAD SELENIUM ALLOYS Separating Fact From Fiction By: Carey O’Donnell & Chuck Finin Background Debate between lead antimony vs. lead calcium has been ongoing for almost 70 years Both are mature ‘technologies’, with major battery producers and users in both camps Batteries based on both alloy types have huge installed bases around the globe Time to take another look for US applications: • New market forces at work • Significant improvements in alloy compositions • Recognize that users are looking for viable options Objectives Provide a brief history of the development and use of both lead selenium (antimony) and lead calcium; objectively compare and contrast the performance and characteristics of each type To attempt to draw conclusions about the performance, reliability, and life expectancy of each alloy type; suitability of each for use in the US Then & Now: Primary Challenges in Battery Manufacturing The improvement of lead alloy compositions for increased tensile strength, improved casting, & conductive performance Developing better compositions & processes for the application and retention of active material on the grids Alloy Debate: Lead Calcium Vs. Lead Selenium Continues to dominate & define much of the technical and market debate in US Good reasons for this: • Impacts grid & product design, long-term product performance & reliability • Directly affects physical strength & hardness of grid; manufacturability • Influences grid corrosion & growth, retention of active material History of Antimony First -
Download PDF About Minerals Sorted by Mineral Name
MINERALS SORTED BY NAME Here is an alphabetical list of minerals discussed on this site. More information on and photographs of these minerals in Kentucky is available in the book “Rocks and Minerals of Kentucky” (Anderson, 1994). APATITE Crystal system: hexagonal. Fracture: conchoidal. Color: red, brown, white. Hardness: 5.0. Luster: opaque or semitransparent. Specific gravity: 3.1. Apatite, also called cellophane, occurs in peridotites in eastern and western Kentucky. A microcrystalline variety of collophane found in northern Woodford County is dark reddish brown, porous, and occurs in phosphatic beds, lenses, and nodules in the Tanglewood Member of the Lexington Limestone. Some fossils in the Tanglewood Member are coated with phosphate. Beds are generally very thin, but occasionally several feet thick. The Woodford County phosphate beds were mined during the early 1900s near Wallace, Ky. BARITE Crystal system: orthorhombic. Cleavage: often in groups of platy or tabular crystals. Color: usually white, but may be light shades of blue, brown, yellow, or red. Hardness: 3.0 to 3.5. Streak: white. Luster: vitreous to pearly. Specific gravity: 4.5. Tenacity: brittle. Uses: in heavy muds in oil-well drilling, to increase brilliance in the glass-making industry, as filler for paper, cosmetics, textiles, linoleum, rubber goods, paints. Barite generally occurs in a white massive variety (often appearing earthy when weathered), although some clear to bluish, bladed barite crystals have been observed in several vein deposits in central Kentucky, and commonly occurs as a solid solution series with celestite where barium and strontium can substitute for each other. Various nodular zones have been observed in Silurian–Devonian rocks in east-central Kentucky. -
Oregon Department of Human Services HEALTH EFFECTS INFORMATION
Oregon Department of Human Services Office of Environmental Public Health (503) 731-4030 Emergency 800 NE Oregon Street #604 (971) 673-0405 Portland, OR 97232-2162 (971) 673-0457 FAX (971) 673-0372 TTY-Nonvoice TECHNICAL BULLETIN HEALTH EFFECTS INFORMATION Prepared by: Department of Human Services ENVIRONMENTAL TOXICOLOGY SECTION Office of Environmental Public Health OCTOBER, 1998 CALCIUM CARBONATE "lime, limewater” For More Information Contact: Environmental Toxicology Section (971) 673-0440 Drinking Water Section (971) 673-0405 Technical Bulletin - Health Effects Information CALCIUM CARBONATE, "lime, limewater@ Page 2 SYNONYMS: Lime, ground limestone, dolomite, sugar lime, oyster shell, coral shell, marble dust, calcite, whiting, marl dust, putty dust CHEMICAL AND PHYSICAL PROPERTIES: - Molecular Formula: CaCO3 - White solid, crystals or powder, may draw moisture from the air and become damp on exposure - Odorless, chalky, flat, sweetish flavor (Do not confuse with "anhydrous lime" which is a special form of calcium hydroxide, an extremely caustic, dangerous product. Direct contact with it is immediately injurious to skin, eyes, intestinal tract and respiratory system.) WHERE DOES CALCIUM CARBONATE COME FROM? Calcium carbonate can be mined from the earth in solid form or it may be extracted from seawater or other brines by industrial processes. Natural shells, bones and chalk are composed predominantly of calcium carbonate. WHAT ARE THE PRINCIPLE USES OF CALCIUM CARBONATE? Calcium carbonate is an important ingredient of many household products. It is used as a whitening agent in paints, soaps, art products, paper, polishes, putty products and cement. It is used as a filler and whitener in many cosmetic products including mouth washes, creams, pastes, powders and lotions. -
Preparation of Barium Strontium Titanate Powder from Citrate
APPLIED ORGANOMETALLIC CHEMISTRY Appl. Organometal. Chem. 13, 383–397 (1999) Preparation of Barium Strontium Titanate Powder from Citrate Precursor Chen-Feng Kao* and Wein-Duo Yang Department of Chemical Engineering, National Cheng Kung University, Tainan, 70101, Taiwan TiCl4 or titanium isopropoxide reacted with INTRODUCTION citric acid to form a titanyl citrate precipitate. Barium strontium citrate solutions were then BaTiO3 is ferroelectric and piezoelectric and has added to the titanyl citrate reaction to form gels. extensive applications as an electronic material. It These gels were dried and calcined to (Ba,Sr)- can be used as a capacitor, thermistor, transducer, TiO3 powders. The gels and powders were accelerometer or degausser of colour television. characterized by DSC/TGA, IR, SEM and BaTiO3 doped with strontium retains its original XRD analyses. These results showed that, at characteristics but has a lower Curie temperature 500 °C, the gels decomposed to Ba,Sr carbonate for positive temperature coefficient devices under and TiO2, followed by the formation of (Ba,Sr)- various conditions. TiO3. The onset of perovskite formation oc- Besides solid-state reactions, chemical reactions curred at 600 °C, and was nearly complete at have also been used to prepare BaTiO3 powder. 1 1000 °C. Traces of SrCO3 were still present. Among them the hydrolysis of metal alkoxide , The cation ratios of the titanate powder oxalate precipitation in ethanol2, and alcoholic prepared in the pH range 5–6 were closest to dehydration of citrate solution3 are among the more the original stoichiometry. Only 0.1 mol% of the attractive methods. In 1956 Clabaugh et al.4 free cations remained in solution. -
Federal Law and Vertebrate Pest Control
University of Nebraska - Lincoln DigitalCommons@University of Nebraska - Lincoln Proceedings of the 1st Vertebrate Pest Vertebrate Pest Conference Proceedings Conference (1962) collection February 1962 FEDERAL LAW AND VERTEBRATE PEST CONTROL Justus C. Ward Director, Pesticides Regulation Division, Agricultural Research Service, U.S. Department of Agriculture Follow this and additional works at: https://digitalcommons.unl.edu/vpcone Part of the Environmental Health and Protection Commons Ward, Justus C., "FEDERAL LAW AND VERTEBRATE PEST CONTROL" (1962). Proceedings of the 1st Vertebrate Pest Conference (1962). 25. https://digitalcommons.unl.edu/vpcone/25 This Article is brought to you for free and open access by the Vertebrate Pest Conference Proceedings collection at DigitalCommons@University of Nebraska - Lincoln. It has been accepted for inclusion in Proceedings of the 1st Vertebrate Pest Conference (1962) by an authorized administrator of DigitalCommons@University of Nebraska - Lincoln. FEDERAL LAW AND VERTEBRATE PEST CONTROL By: Justus C. Ward, Director, Pesticides Regulation Division, Agricultural Research Service, U.S. Department of Agriculture Presented at the Vertebrate Pest Control Conference, Sacramento, California, February 6 and 7, 1 962 Shortly after the passage of the Federal Insecticide Act of 1910> mammal control specialists in the Bureau of Biological Survey began to consider a similar law to cover the chemicals with which they were concerned. Work on the project went slowly a nd spasmodically, but reached the point of having a Federal Rodenticide Act available for study and possible revision in 1928. At this time, the mammal control chemicals in use were limited to strychnine -- alkaloid and sulphate -arsenic, barium carbonate, th allium sulphate, phosphorus, s odium and calcium cyanide, carbon disulphide, and red squill. -
PUBLIC HEALTH STATEMENT Cesium CAS#: 7440-46-2
PUBLIC HEALTH STATEMENT Cesium CAS#: 7440-46-2 Division of Toxicology April 2004 This Public Health Statement is the summary exposed to a substance when you come in contact chapter from the Toxicological Profile for cesium. It with it. You may be exposed by breathing, eating, is one in a series of Public Health Statements about or drinking the substance, or by skin contact. If the hazardous substances and their health effects. A substance is radioactive, you may also be exposed shorter version, the ToxFAQs™, is also available. to radiation if you are near it. This information is important because this substance may harm you. The effects of exposure to External exposure to radiation may occur from any hazardous substance depend on the dose, the natural or man-made sources. Naturally occurring duration, how you are exposed, personal traits and sources of radiation are cosmic radiation from space habits, and whether other chemicals are present. For or radioactive materials in soil or building materials. more information, call the ATSDR Information Man-made sources of radioactive materials are Center at 1-888-422-8737. found in consumer products, industrial equipment, _____________________________________ atom bomb fallout, and to a smaller extent from This public health statement tells you about cesium hospital waste, medical devices, and nuclear and the effects of exposure. reactors. The Environmental Protection Agency (EPA) If you are exposed to cesium, many factors identifies the most serious hazardous waste sites in determine whether you’ll be harmed. These factors the nation. These sites make up the National include the dose (how much), the duration (how Priorities List (NPL) and are the sites targeted for long), and how you come in contact with it. -
Of the Periodic Table
of the Periodic Table teacher notes Give your students a visual introduction to the families of the periodic table! This product includes eight mini- posters, one for each of the element families on the main group of the periodic table: Alkali Metals, Alkaline Earth Metals, Boron/Aluminum Group (Icosagens), Carbon Group (Crystallogens), Nitrogen Group (Pnictogens), Oxygen Group (Chalcogens), Halogens, and Noble Gases. The mini-posters give overview information about the family as well as a visual of where on the periodic table the family is located and a diagram of an atom of that family highlighting the number of valence electrons. Also included is the student packet, which is broken into the eight families and asks for specific information that students will find on the mini-posters. The students are also directed to color each family with a specific color on the blank graphic organizer at the end of their packet and they go to the fantastic interactive table at www.periodictable.com to learn even more about the elements in each family. Furthermore, there is a section for students to conduct their own research on the element of hydrogen, which does not belong to a family. When I use this activity, I print two of each mini-poster in color (pages 8 through 15 of this file), laminate them, and lay them on a big table. I have students work in partners to read about each family, one at a time, and complete that section of the student packet (pages 16 through 21 of this file). When they finish, they bring the mini-poster back to the table for another group to use. -
The Chemistry of Strontium and Barium Scales
Association of Water Technologies October 20 -23, 2010 Reno, NV, USA The Chemistry of Strontium and Barium Scales Robert J. Ferguson and Baron R. Ferguson French Creek Software, Inc. Kimberton, PA 19442 (610) 935-8337 (610) 935-1008 FAX [email protected] [email protected] Abstract New ‘mystery scales’ are being encountered as cooling tower operators increase cycles to new highs, add ‘reuse’ water to the make-up, and utilize new make-up water sources as part of an overall water conservation strategy. Scales rarely, if ever, encountered in the past are emerging as potential problems. This threat of unexpected scale is compounded because most water treatment service companies do not include barium and strontium in their make-up water analyses. Water sources with even as little 0.01 mg/L of Ba (as Ba) can become very scale-forming with respect to barite (BaSO4) when tower concentration ratios are increased and sulfuric acid used for pH control. Make-up waters incorporating reverse osmosis concentrate can also provide a strontium and barium source. In some cases, produced waters are also being used in an effort for greener water use. This paper discusses the chemistry of the barium and strontium based scales barite (BaSO4), celestite (SrSO4), witherite (BaCO3) and strontianite (SrCO3). Conditions for formation and control from a water treater’s perspective are emphasized. Indices for prediction are discussed. Scale Prediction and the Concept of Saturation A majority of the indices used routinely by water treatment chemists are derived from the basic concept of saturation. A water is said to be saturated with a compound (e.g. -
Barite (Barium)
Barite (Barium) Chapter D of Critical Mineral Resources of the United States—Economic and Environmental Geology and Prospects for Future Supply Professional Paper 1802–D U.S. Department of the Interior U.S. Geological Survey Periodic Table of Elements 1A 8A 1 2 hydrogen helium 1.008 2A 3A 4A 5A 6A 7A 4.003 3 4 5 6 7 8 9 10 lithium beryllium boron carbon nitrogen oxygen fluorine neon 6.94 9.012 10.81 12.01 14.01 16.00 19.00 20.18 11 12 13 14 15 16 17 18 sodium magnesium aluminum silicon phosphorus sulfur chlorine argon 22.99 24.31 3B 4B 5B 6B 7B 8B 11B 12B 26.98 28.09 30.97 32.06 35.45 39.95 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 potassium calcium scandium titanium vanadium chromium manganese iron cobalt nickel copper zinc gallium germanium arsenic selenium bromine krypton 39.10 40.08 44.96 47.88 50.94 52.00 54.94 55.85 58.93 58.69 63.55 65.39 69.72 72.64 74.92 78.96 79.90 83.79 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 rubidium strontium yttrium zirconium niobium molybdenum technetium ruthenium rhodium palladium silver cadmium indium tin antimony tellurium iodine xenon 85.47 87.62 88.91 91.22 92.91 95.96 (98) 101.1 102.9 106.4 107.9 112.4 114.8 118.7 121.8 127.6 126.9 131.3 55 56 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 cesium barium hafnium tantalum tungsten rhenium osmium iridium platinum gold mercury thallium lead bismuth polonium astatine radon 132.9 137.3 178.5 180.9 183.9 186.2 190.2 192.2 195.1 197.0 200.5 204.4 207.2 209.0 (209) (210)(222) 87 88 104 105 106 107 108 109 110 111 112 113 114 115 116 -
Adsorption of RNA on Mineral Surfaces and Mineral Precipitates
Adsorption of RNA on mineral surfaces and mineral precipitates Elisa Biondi1,2, Yoshihiro Furukawa3, Jun Kawai4 and Steven A. Benner*1,2,5 Full Research Paper Open Access Address: Beilstein J. Org. Chem. 2017, 13, 393–404. 1Foundation for Applied Molecular Evolution, 13709 Progress doi:10.3762/bjoc.13.42 Boulevard, Alachua, FL, 32615, USA, 2Firebird Biomolecular Sciences LLC, 13709 Progress Boulevard, Alachua, FL, 32615, USA, Received: 23 November 2016 3Department of Earth Science, Tohoku University, 2 Chome-1-1 Accepted: 15 February 2017 Katahira, Aoba Ward, Sendai, Miyagi Prefecture 980-8577, Japan, Published: 01 March 2017 4Department of Material Science and Engineering, Yokohama National University, 79-5 Tokiwadai, Hodogaya-ku, Yokohama This article is part of the Thematic Series "From prebiotic chemistry to 240-8501, Japan and 5The Westheimer Institute for Science and molecular evolution". Technology, 13709 Progress Boulevard, Alachua, FL, 32615, USA Guest Editor: L. Cronin Email: Steven A. Benner* - [email protected] © 2017 Biondi et al.; licensee Beilstein-Institut. License and terms: see end of document. * Corresponding author Keywords: carbonates; natural minerals; origins of life; RNA adsorption; synthetic minerals Abstract The prebiotic significance of laboratory experiments that study the interactions between oligomeric RNA and mineral species is difficult to know. Natural exemplars of specific minerals can differ widely depending on their provenance. While laboratory-gener- ated samples of synthetic minerals can have controlled compositions, they are often viewed as "unnatural". Here, we show how trends in the interaction of RNA with natural mineral specimens, synthetic mineral specimens, and co-precipitated pairs of synthe- tic minerals, can make a persuasive case that the observed interactions reflect the composition of the minerals themselves, rather than their being simply examples of large molecules associating nonspecifically with large surfaces. -
Material Safety Data Sheet Version 3.4 Revision Date 09/03/2012 Print Date 02/06/2014
SIGMA-ALDRICH sigma-aldrich.com Material Safety Data Sheet Version 3.4 Revision Date 09/03/2012 Print Date 02/06/2014 1. PRODUCT AND COMPANY IDENTIFICATION Product name : Strontium chloride solution Product Number : 69042 Brand : Sigma Supplier : Sigma-Aldrich 3050 Spruce Street SAINT LOUIS MO 63103 USA Telephone : +1 800-325-5832 Fax : +1 800-325-5052 Emergency Phone # (For : (314) 776-6555 both supplier and manufacturer) Preparation Information : Sigma-Aldrich Corporation Product Safety - Americas Region 1-800-521-8956 2. HAZARDS IDENTIFICATION Emergency Overview OSHA Hazards Irritant GHS Classification Skin irritation (Category 3) Eye irritation (Category 2A) GHS Label elements, including precautionary statements Pictogram Signal word Warning Hazard statement(s) H316 Causes mild skin irritation. H319 Causes serious eye irritation. Precautionary statement(s) P305 + P351 + P338 IF IN EYES: Rinse cautiously with water for several minutes. Remove contact lenses, if present and easy to do. Continue rinsing. HMIS Classification Health hazard: 2 Flammability: 0 Physical hazards: 0 NFPA Rating Health hazard: 2 Fire: 0 Reactivity Hazard: 0 Potential Health Effects Inhalation May be harmful if inhaled. Causes respiratory tract irritation. Skin May be harmful if absorbed through skin. Causes skin irritation. Sigma - 69042 Page 1 of 6 Eyes Causes eye irritation. Ingestion May be harmful if swallowed. 3. COMPOSITION/INFORMATION ON INGREDIENTS Synonyms : Strontium chloridesolution Additive Screening Solution 27/Fluka kit no 78374 Component Classification Concentration Strontium chloride CAS-No. 10476-85-4 Skin Irrit. 2; Eye Dam. 1; 1 - 5 % EC-No. 233-971-6 STOT SE 3; H315, H318, H335 For the full text of the H-Statements and R-Phrases mentioned in this Section, see Section 16 4.