Compounds of the Metals Beryllium, Magnesium
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Determination of Aluminium As Oxide
DETERMINATION OF ALUMINIUM AS OXIDE By William Blum CONTENTS Page I. Introduction 515 II. General principles 516 III. Historical 516 IV. Precipitation of aluminium hydroxide. 518 1. Hydrogen electrode studies 518 (a) The method 518 (b) Apparatus and solutions employed 518 (c) Results of hydrogen electrode experiments 519 (d) Conclusions from hydrogen electrode experiments 520 2. Selection of an indicator for denning the conditions of precipita- '. tion . 522 3. Factors affecting the form of the precipitate 524 4. Precipitation in the presence of iron 525 V. Washing the precipitate . 525 VI. Separation from other elements 526 VII. Ignition and weighing of the precipitate 528 1. Hygroscopicity of aluminium oxide 529 2. Temperature and time of ignition 529 3. Effect of ammonium chloride upon the ignition 531 VIII. Procedure recommended 532 IX. Confirmatory experiments 532 X. Conclusions '534 I. INTRODUCTION Although a considerable number of precipitants have been pro- posed for the determination of aluminium, direct precipitation of aluminium hydroxide by means of ammonium hydroxide, fol- lowed by ignition to oxide, is most commonly used, especially if no separation from iron is desired, in which latter case special methods must be employed. While the general principles involved in this determination are extremely simple, it has long been recog- nized that certain precautions in the precipitation, washing, and ignition are necessary if accurate results are to be obtained. While, however, most of these details have been studied and dis- cussed by numerous authors, it is noteworthy that few publica- tions or textbooks have taken account of all the factors. In the 515 ; 516 Bulletin of the Bureau of Standards [Voi.i3 present paper it seems desirable, therefore, to assemble the various recommendations and to consider their basis and their accuracy. -
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. -
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. -
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 -
A Novel Method for Synthesis of Nano-C-Al2o3: Study of Adsorption Behavior of Chromium, Nickel, Cadmium and Lead Ions
Int. J. Environ. Sci. Technol. (2015) 12:2003–2014 DOI 10.1007/s13762-014-0740-7 ORIGINAL PAPER A novel method for synthesis of nano-c-Al2O3: study of adsorption behavior of chromium, nickel, cadmium and lead ions A. Shokati Poursani • A. Nilchi • A. H. Hassani • M. Shariat • J. Nouri Received: 30 April 2014 / Revised: 5 November 2014 / Accepted: 22 December 2014 / Published online: 14 January 2015 Ó Islamic Azad University (IAU) 2015 Abstract Nano-c-Al2O3 adsorbent was synthesized by Introduction the novel sol–gel method. The adsorbent was characterized by transmission electron microscope, Fourier transform Heavy metal pollution occurs during different industrial infrared and X-ray powder diffraction. The effects of sev- activities, and rapid industrialization leads to the increase eral variables such as, adsorbent weight, pH and contact of heavy metal concentration in the environment (Rahmani time on adsorption of chromium (Cr6?), nickel (Ni2?), et al. 2010). It can also increase the concentration of heavy cadmium (Cd2?) and lead (Pb2?) ions were studied in metal ions, such as cadmium (Cd), lead (Pb), zinc (Zn), batch experiments. The results showed that the synthesized nickel (Ni), copper (Cu) and chromium (VI) in water nano-c-Al2O3 had a good capacity to adsorb Cr and Pb. resources (Aziz et al. 2008). The toxic nature of heavy The kinetic data were described with pseudo-first- and metals has caused serious health problems for human, and pseudo-second-order models. Three isotherm models, they can accumulate in the environment (Rahmani et al. namely Freundlich, Langmuir and Tempkin, were used for 2010). In addition, recovery and removal of heavy metals analysis of equilibrium data, and results showed that are principal purposes in industry and saving clean water Langmuir and Freundlich models were suitable for resources (Sharma and Tamar 2008; Neghlani et al. -
Paediatric Barium Swallow/Meal Information for Parents and Carers Your Doctor Has Referred Your Child for a Barium Swallow/Meal to Look at Their Food Pipe and Stomach
Oxford University Hospitals NHS Trust Paediatric Barium Swallow/Meal Information for parents and carers Your doctor has referred your child for a barium swallow/meal to look at their food pipe and stomach. We have written this information leaflet to help you and your child to understand this test. We hope it answers some of the questions you both may have and helps you and your child to feel more prepared and relaxed. page 2 What is a barium swallow/meal? A barium swallow/meal uses a special liquid to allow the X-ray doctor (radiologist) to see your child’s oesophagus (food pipe or gullet), stomach and the first part of their intestines using an X-ray camera. What does this test involve? Your child will be asked to drink a special drink called barium. This is a white liquid with a chalky texture. It is not radioactive but is used as it shows up well on X-ray images. Your child will need to drink the barium whilst lying on a couch with the X-ray camera over their tummy (about 75cm away). They may need to change position, so you will be asked to stay close to them at all times to make sure they are safe. If your child is able to, they will usually be asked to drink using a straw so that they can stay lying down. If they are not able to use a straw they can drink the barium from a bottle or beaker. If they are currently being fed through a nasogastric (NG) tube, we will use that to give them the barium. -
Absence of Skin Sensitivity to Oxides of Aluminium, Silicon, Titanium Or Zirconium in Patients With
Gut1996;39:231-233 231 Absence of skin sensitivity to oxides of aluminium, Silicon, titanium or zirconium in patients with Crohn's disease Gut: first published as 10.1136/gut.39.2.231 on 1 August 1996. Downloaded from J C W Lee, S Halpem, D G Lowe, A Forbes, J E Lennard-Jones Abstract obstructive lymphadenopathy. It has been Background-Some metallic compounds, proposed that this is caused by fibrosis of the especially of zirconium, can cause cell afferent lymphatics as a result of absorption of mediated granulomatous inflammation of microparticles of silica and alumino-silicates the skin. Pigment granules containing through the skin where people walk barefoot compounds of aluminium, silicon, and on certain types of soil. Particles containing titanium have been observed within silica, titanium, and aluminium are present in macrophages in the wall of the small microgranulomata within inguinal lymph intestine in health and in Crohn's disease. nodes of sufferers.6 Granulomata also develop Zirconium compounds can be ingested in in response to intradermal injection ofcolloidal toothpaste. silica in healthy subjects but these are foreign Aim-To determine in a pilot study if body granulomata and are clearly distinguish- granulomatous sensitivity can be detected able from the cell mediated response to small to compounds of these metals or silicon quantities of zirconium lactate.7 after injection into the skin of patients As metals and minerals are ubiquitous in the with Crohn's disease. community, a hypersensitivity to these sub- Subjects-Eight patients with Crohn's stances in some people rather than a direct disease known to have had granulomata in toxic effect is the most probable pathogenetic the intestine and not currently treated mechanism by which they may contribute to with corticosteroids, and two healthy disease. -
The Adsorption Characteristics of Cu(II)
www.nature.com/scientificreports OPEN The adsorption characteristics of Cu(II) and Zn(II) on the sediments at the mouth of a typical urban polluted river in Dianchi Lake: taking Xinhe as an example Xiang‑shu Ma1,2,3, Leng Liu1,2,3, Yi‑chuan Fang1,2,3 & Xiao‑long Sun1,2,3* This study is to determine the spatial distribution characteristics of Cu and Zn adsorption on the sediments of the estuary of Dianchi Lake, as well as the composite adsorption law of Cu and Zn on combinations of sediment organic matter, metal oxides, and organic–inorganic composites. The relationship between the adsorption contribution of each component of the substance. A static adsorption experiment was applied to the sediments in the estuary of Dianchi Lake. The relationship between adsorption capacity and sediment composition was analyzed through correlation analysis and redundant analysis. The results show that along the direction of the river fow and the vertical depth, the adsorption capacity presents a relatively obvious spatial distribution law; the change trend of sediment component content is not the same as the change trend of Cu and Zn adsorption capacity. The change trend of the sediment component content is not the same as the change trend of the adsorption amount of Cu and Zn, and the compound efect between the components afects the adsorption amount. The adsorption of Cu by the four groups of sediments after diferent treatments is more in line with the Freundlich isotherm adsorption model; When adsorbing Zn, the untreated and removed organic matter and iron‑aluminum oxide group are in good agreement with the Freundlich model, while the organic matter‑removed group and the iron‑aluminum oxide removal group are more consistent with the Langmuir isotherm adsorption model; The adsorption contribution rate of organic–inorganic composites in sediments is not a simple addition of organic matter and iron‑ aluminum oxides, but a more complex quantitative relationship. -
Absorption of X-Rays by Lead Glasses and Lead Barium Glasses
U. S. DEPARTMENT OF COMMERCE NATIONAL BUREAU OF STANDARDS RESEARCH PAPER RP870 Part of Journal of Research of the National Bureau of Standards, Volume 16, March 1936 ABSORPTION OF X"RAYS BY LEAD GLASSES AND LEAD BARIUM GLASSES By George Singer ABSTRACT The results of a study of the protective properties of a group of typical flint and barium-flint glasses are reported. In chemical composition, the protective glasses analyzed were found to resemble closely the denser optical flint and barium-flint glasses. The protection coefficients of the glasses were determined by an ionization method; of the various component elements it was found that only lead and barium contribute appreciably to the protective effectiveness of the glasses. For flint glass empirical relations were established between the protection coefficient and the chemical composition, density, and refractivity; for barium flint glass an empirical relation is given between the protection coefficient and the lead-oxide and barium-oxide components of the glass. CONTENTS Page 1. Introduction__ __ _ _ _ _ __ _ _ _ __ _ _ _ __ _ _ _ __ _ _ _ _ _ _ _ ___ _ _ _ _ _ _ _ _ _ _ _ _ _ 233 II. Methods of determining the protection coefficient of a materiaL___ 234 III. Experimental procedure_ ___ _ __ _ _ _ _ _ _ __ __ _ _ _ _ _ _ __ _ _ _ __ _ _ _ _ _ _ _ _ 235 IV. Description of glasses_ __ _ _ _ __ _ _ _ __ _ _ __ __ __ _ _ _ ______ __ _ _ _ _ _ _ _ _ 237 V. -
208143 Barium Sulfate Statistical Prea
Table of Contents LIST OF TABLES ........................................................................................................................ 3 1. EXECUTIVE SUMMARY ................................................................................................ 4 2. INTRODUCTION............................................................................................................... 7 2.1 OVERVIEW .......................................................................................................................... 7 2.1.1 Regulatory History .......................................................................................................... 7 2.1.2 Doses ............................................................................................................................... 8 2.1.3 Identified Studies in the review ....................................................................................... 8 2.1.4 Analysis Populations ....................................................................................................... 8 2.2 DATA SOURCES ................................................................................................................ 10 3. STATISTICAL EVALUATION...................................................................................... 11 3.1 DATA AND ANALYSIS QUALITY ........................................................................................ 11 3.2 EVALUATION OF EFFICACY .............................................................................................. -
The Role of Calcium and Strontium As the Most Dominant Elements During
crystals Article The Role of Calcium and Strontium as the Most Dominant Elements during Combinations of Different Alkaline Earth Metals in the Synthesis of Crystalline Silica-Carbonate Biomorphs Mayra Cuéllar-Cruz 1,2,* and Abel Moreno 2,* 1 Departamento de Biología, División de Ciencias Naturales y Exactas, Campus Guanajuato, Universidad de Guanajuato, Noria Alta S/N, Col. Noria Alta, Guanajuato C.P. 36050, Mexico 2 Instituto de Química, Universidad Nacional Autónoma de México, Av. Universidad 3000, Ciudad Universitaria, Ciudad de México 04510, Mexico * Correspondence: [email protected] (M.C.-C.); [email protected] (A.M.) Received: 22 June 2019; Accepted: 22 July 2019; Published: 24 July 2019 Abstract: The origin of life from the chemical point of view is an intriguing and fascinating topic, and is of continuous interest. Currently, the chemical elements that are part of the different cellular types from microorganisms to higher organisms have been described. However, although science has advanced in this context, it has not been elucidated yet which were the first chemical elements that gave origin to the first primitive cells, nor how evolution eliminated or incorporated other chemical elements to give origin to other types of cells through evolution. Calcium, barium, and strontium silica-carbonates have been obtained in vitro and named biomorphs, because they mimic living organism structures. Therefore, it is considered that these forms can resemble the first structures that were part of primitive organisms. Hence, the objective of this work was to synthesize biomorphs starting with different mixtures of alkaline earth metals—beryllium (Be2+), magnesium (Mg2+), calcium (Ca2+), barium (Ba2+), and strontium (Sr2+)—in the presence of nucleic acids, RNA and genomic DNA (gDNA).