The Effect of Chromium on White Cast Iron Clarence D
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A New Occurrence of Terrestrial Native Iron in the Earth's Surface
geosciences Article A New Occurrence of Terrestrial Native Iron in the Earth’s Surface: The Ilia Thermogenic Travertine Case, Northwestern Euboea, Greece Christos Kanellopoulos 1,2,* ID , Eugenia Valsami-Jones 3,4, Panagiotis Voudouris 1, Christina Stouraiti 1 ID , Robert Moritz 2, Constantinos Mavrogonatos 1 ID and Panagiotis Mitropoulos 1,† 1 Department of Geology and Geoenvironment, National and Kapodistrian University of Athens, Panepistimioupolis Zografou, 15784 Athens, Greece; [email protected] (P.V.); [email protected] (C.S.); [email protected] (C.M.); [email protected] (P.M.) 2 Section of Earth and Environmental Sciences, University of Geneva, Rue des Maraichers 13, 1205 Geneva, Switzerland; [email protected] 3 School of Geography, Earth & Environmental Sciences, University of Birmingham, Edgbaston, Birmingham B15 2TT, UK; [email protected] 4 Department of Earth Sciences, Natural History Museum London, Cromwell Road, London SW7 5BD, UK * Correspondence: [email protected] † Professor Panagiotis Mitropoulos has passed away in 2017. Received: 6 April 2018; Accepted: 23 July 2018; Published: 31 July 2018 Abstract: Native iron has been identified in an active thermogenic travertine deposit, located at Ilia area (Euboea Island, Greece). The deposit is forming around a hot spring, which is part of a large active metallogenetic hydrothermal system depositing ore-bearing travertines. The native iron occurs in two shapes: nodules with diameter 0.4 and 0.45 cm, and angular grains with length up to tens of µm. The travertine laminae around the spherical/ovoid nodules grow smoothly, and the angular grains are trapped inside the pores of the travertine. -
Historical Development of the Periodic Classification of the Chemical Elements
THE HISTORICAL DEVELOPMENT OF THE PERIODIC CLASSIFICATION OF THE CHEMICAL ELEMENTS by RONALD LEE FFISTER B. S., Kansas State University, 1962 A MASTER'S REPORT submitted in partial fulfillment of the requirements for the degree FASTER OF SCIENCE Department of Physical Science KANSAS STATE UNIVERSITY Manhattan, Kansas 196A Approved by: Major PrafeLoor ii |c/ TABLE OF CONTENTS t<y THE PROBLEM AND DEFINITION 0? TEH-IS USED 1 The Problem 1 Statement of the Problem 1 Importance of the Study 1 Definition of Terms Used 2 Atomic Number 2 Atomic Weight 2 Element 2 Periodic Classification 2 Periodic Lav • • 3 BRIEF RtiVJiM OF THE LITERATURE 3 Books .3 Other References. .A BACKGROUND HISTORY A Purpose A Early Attempts at Classification A Early "Elements" A Attempts by Aristotle 6 Other Attempts 7 DOBEREBIER'S TRIADS AND SUBSEQUENT INVESTIGATIONS. 8 The Triad Theory of Dobereiner 10 Investigations by Others. ... .10 Dumas 10 Pettehkofer 10 Odling 11 iii TEE TELLURIC EELIX OF DE CHANCOURTOIS H Development of the Telluric Helix 11 Acceptance of the Helix 12 NEWLANDS' LAW OF THE OCTAVES 12 Newlands' Chemical Background 12 The Law of the Octaves. .........' 13 Acceptance and Significance of Newlands' Work 15 THE CONTRIBUTIONS OF LOTHAR MEYER ' 16 Chemical Background of Meyer 16 Lothar Meyer's Arrangement of the Elements. 17 THE WORK OF MENDELEEV AND ITS CONSEQUENCES 19 Mendeleev's Scientific Background .19 Development of the Periodic Law . .19 Significance of Mendeleev's Table 21 Atomic Weight Corrections. 21 Prediction of Hew Elements . .22 Influence -
Stoichiometry: the Reaction of Iron with Copper(II) Sulfate
CEAC 103 GENERAL CHEMISTRY Experiment 2 Stoichiometry: The Reaction of Iron with Copper(II) Sulfate Purpose: To enhance the understanding of stoichiometry, a reaction between iron and copper (II) sulfate solution will be conducted. This will help you to differentiate limiting and excess reactant in a chemical reaction. Finally the theoretical and percent yield of this reaction will be calculated. Theory Stoichiometry is the measurement of quantitative relationships in chemical formulas and equations. In this experiment stoichiometric principles will be used to obtain the appropriate equation between the reaction of iron metal and copper(II) sulfate solution. After the reaction is taking place, the formation of metallic copper, which is seen precipitating as a finely divided reddish-orange powder will be observed. This reaction is one of the example of single substitution reaction in which one element “displaces” from a compound by another element. The element which has ability of displacing other element from compound is said to be “more active” than the displaced metal. In this experiment, iron is more active than copper. Two distinct forms of iron are present, namely Fe2+ and Fe3+. Stoichiometric principles will be used to determine which reaction is more dominant compared to other one by examining the reaction between iron and copper (II) sulfate solution. If Fe2+ is formed, then equation (1) is dominant, while equation (2) will be selected if Fe3+ is formed. This can be determined 1 according to mole ratio of copper to iron. If the moles of copper is equal to the moles of iron, then equation (1) has taken place. -
Chromium Compounds Hazard Summary
Chromium Compounds Hazard Summary Chromium occurs in the environment primarily in two valence states, trivalent chromium (Cr III) and hexavalent chromium (Cr VI). Exposure may occur from natural or industrial sources of chromium. Chromium III is much less toxic than chromium (VI). The respiratory tract is also the major target organ for chromium (III) toxicity, similar to chromium (VI). Chromium (III) is an essential element in humans. The body can detoxify some amount of chromium (VI) to chromium (III). The respiratory tract is the major target organ for chromium (VI) toxicity, for acute (short-term) and chronic (long-term) inhalation exposures. Shortness of breath, coughing, and wheezing were reported from a case of acute exposure to chromium (VI), while perforations and ulcerations of the septum, bronchitis, decreased pulmonary function, pneumonia, and other respiratory effects have been noted from chronic exposure. Human studies have clearly established that inhaled chromium (VI) is a human carcinogen, resulting in an increased risk of lung cancer. Animal studies have shown chromium (VI) to cause lung tumors via inhalation exposure. Please Note: The main sources of information for this fact sheet are EPA's Integrated Risk Information System (IRIS) (7), which contains information on inhalation chronic toxicity and the RfC and oral chronic toxicity and the RfD, and the carcinogenic effects of chromium including the unit cancer risk for inhalation exposure, EPA's Toxicological Review of Trivalent Chromium and Toxicological Review of Hexavalent Chromium (3), and the Agency for Toxic Substances and Disease Registry's (ATSDR's) Toxicological Profile for Chromium. (1) Uses The metal chromium is used mainly for making steel and other alloys. -
Iron –Carbon Phase Diagram
IRON –CARBON PHASE DIAGRAM CB.EN.P2MFG15018 Definition of structures: Various phases that appear on the Iron- Carbon equilibrium phase diagram are as under: • Austenite • Ferrite • Pearlite • Cementite • Martensite • Ledeburite Definition of structures: Austenite is an interstitial solid solution of Carbon dissolved in (F.C.C.) iron. Maximum solubility is 2.0 % C at 1130°C. High formability, most of heat treatments begin with this single phase. It is normally not stable at room temperature. But, under certain conditions it is possible to obtain austenite at room temperature. Austenite Average properties are: Tensile strength = 150,000 psi; Elongation = 10 percent in 2 in.; Hardness = Rockwell C 40, approx; and toughness = high Definition of structures: Ferrite is known as α solid solution. It is an interstitial solid solution of a small amount of carbon dissolved in α (BCC) iron. stable form of iron below 912 deg.C. The maximum solubility is 0.025 % C at 723C and it dissolves only 0.008 % C at room temperature. It is the softest structure that appears on the diagram. Ferrite Average properties are: Tensile strength = 40,000 psi; Elongation = 40 % in 2 in; Hardness > Rockwell C 0 or > Rockwell B 90 Definition of structures: Pearlite is the eutectoid mixture containing 0.80 % C and is formed at 723°C on very slow cooling. It is a very fine platelike or lamellar mixture of ferrite and cementite. The white ferritic background or matrix contains thin plates of cementite (dark). Pearlite Average properties are: Tensile strength = 120,000 psi; Elongation = 20 % in 2 in.; Hardness = Rockwell C20, BHN-300 Definition of structures: Cementite or iron carbide, is very hard, brittle intermetallic compound of iron & carbon, as Fe3C, contains 6.67 % C. -
Structure/Property Relationships in Irons and Steels Bruce L
Copyright © 1998 ASM International® Metals Handbook Desk Edition, Second Edition All rights reserved. J.R. Davis, Editor, p 153-173 www.asminternational.org Structure/Property Relationships in Irons and Steels Bruce L. Bramfitt, Homer Research Laboratories, Bethlehem Steel Corporation Basis of Material Selection ............................................... 153 Role of Microstructure .................................................. 155 Ferrite ............................................................. 156 Pearlite ............................................................ 158 Ferrite-Pearl ite ....................................................... 160 Bainite ............................................................ 162 Martensite .................................... ...................... 164 Austenite ........................................................... 169 Ferrite-Cementite ..................................................... 170 Ferrite-Martensite .................................................... 171 Ferrite-Austenite ..................................................... 171 Graphite ........................................................... 172 Cementite .......................................................... 172 This Section was adapted from Materials 5election and Design, Volume 20, ASM Handbook, 1997, pages 357-382. Additional information can also be found in the Sections on cast irons and steels which immediately follow in this Handbook and by consulting the index. THE PROPERTIES of irons and steels -
Materials Technology – Placement
MATERIAL TECHNOLOGY 01. An eutectoid steel consists of A. Wholly pearlite B. Pearlite and ferrite C. Wholly austenite D. Pearlite and cementite ANSWER: A 02. Iron-carbon alloys containing 1.7 to 4.3% carbon are known as A. Eutectic cast irons B. Hypo-eutectic cast irons C. Hyper-eutectic cast irons D. Eutectoid cast irons ANSWER: B 03. The hardness of steel increases if it contains A. Pearlite B. Ferrite C. Cementite D. Martensite ANSWER: C 04. Pearlite is a combination of A. Ferrite and cementite B. Ferrite and austenite C. Ferrite and iron graphite D. Pearlite and ferrite ANSWER: A 05. Austenite is a combination of A. Ferrite and cementite B. Cementite and gamma iron C. Ferrite and austenite D. Pearlite and ferrite ANSWER: B 06. Maximum percentage of carbon in ferrite is A. 0.025% B. 0.06% C. 0.1% D. 0.25% ANSWER: A 07. Maximum percentage of carbon in austenite is A. 0.025% B. 0.8% 1 C. 1.25% D. 1.7% ANSWER: D 08. Pure iron is the structure of A. Ferrite B. Pearlite C. Austenite D. Ferrite and pearlite ANSWER: A 09. Austenite phase in Iron-Carbon equilibrium diagram _______ A. Is face centered cubic structure B. Has magnetic phase C. Exists below 727o C D. Has body centered cubic structure ANSWER: A 10. What is the crystal structure of Alpha-ferrite? A. Body centered cubic structure B. Face centered cubic structure C. Orthorhombic crystal structure D. Tetragonal crystal structure ANSWER: A 11. In Iron-Carbon equilibrium diagram, at which temperature cementite changes fromferromagnetic to paramagnetic character? A. -
Why We Need to Assure Adequacy of Zinc
Aunt Cathy’s Guide to Nutrition: Sanford Nutrition Therapy Dept. 1/15 Thinking about Clinical/Medical Nutrition Issues and Applications of RDAs, RDI, DRIs, ULS, AIs, etc.: Why We Need to Assure Adequacy of Zinc (from the series “How Am I Supposed to Remember All This Stuff?!”) Aunt Cathy Cathy Breedon PhD, RD, CSP, FADA, FAND Clinical and Metabolic Nutrition Specialist / Prenatal/Pediatric Nutrition Specialist Sanford Medical Center, and Clinical Associate Professor UND School of Medicine, Fargo, ND • Zinc is a necessary mineral cofactor needed for over 200 enzymes to work. • Not having enough screws stuff up a LOT. • What kinds of things won’t work well if zinc is inadequate? Read on … 1 Memory Tricks for ZINC Many people remember things best if they also see pictures, so here are some pictures identifying some specific places in the body for which zinc is absolutely essential. Other folks remember things best if they hear them … so if you are one of those people, be sure to read the descriptor for each function of zinc out loud. The Zinc Story: “Zinco” (Zorro’s more irritating cousin) has just marked the places where people need zinc for their bodies to operate. Just picture the fellow on the left to remember that zinc is needed all over the body. It is a co-factor for over 200 enzymes! In other words … I dare you to name a body part that is not dependent on adequacy of zinc! Here are some specific places where he marked things with a Z for Zinc: Zinc is need to make DNA So Zinc is needed And Zinc is needed to to make new cells for babies -
Adverse Health Effects of Heavy Metals in Children
TRAINING FOR HEALTH CARE PROVIDERS [Date …Place …Event …Sponsor …Organizer] ADVERSE HEALTH EFFECTS OF HEAVY METALS IN CHILDREN Children's Health and the Environment WHO Training Package for the Health Sector World Health Organization www.who.int/ceh October 2011 1 <<NOTE TO USER: Please add details of the date, time, place and sponsorship of the meeting for which you are using this presentation in the space indicated.>> <<NOTE TO USER: This is a large set of slides from which the presenter should select the most relevant ones to use in a specific presentation. These slides cover many facets of the problem. Present only those slides that apply most directly to the local situation in the region. Please replace the examples, data, pictures and case studies with ones that are relevant to your situation.>> <<NOTE TO USER: This slide set discusses routes of exposure, adverse health effects and case studies from environmental exposure to heavy metals, other than lead and mercury, please go to the modules on lead and mercury for more information on those. Please refer to other modules (e.g. water, neurodevelopment, biomonitoring, environmental and developmental origins of disease) for complementary information>> Children and heavy metals LEARNING OBJECTIVES To define the spectrum of heavy metals (others than lead and mercury) with adverse effects on human health To describe the epidemiology of adverse effects of heavy metals (Arsenic, Cadmium, Copper and Thallium) in children To describe sources and routes of exposure of children to those heavy metals To understand the mechanism and illustrate the clinical effects of heavy metals’ toxicity To discuss the strategy of prevention of heavy metals’ adverse effects 2 The scope of this module is to provide an overview of the public health impact, adverse health effects, epidemiology, mechanism of action and prevention of heavy metals (other than lead and mercury) toxicity in children. -
Iron in Minnesota's Ground Water
Iron in Minnesota’s Ground Water Environmental Outcomes Division Ground Water May 1999 Monitoring & Assessment What is iron? is soil beneath metal recyclers. However, Program Iron is a chemical element that is widely despite these high concentrations, only distributed in geologic materials. Iron is small quantities of iron are likely to leach slowly released from soil and rocks to to the ground water. ground water. What is considered a safe level of iron The fate of iron in ground water depends in ground water? on the form of iron present. Under The Secondary Maximum Contaminant reducing conditions, ferrous iron (FeII or Level (SMCL) for iron is 0.30 mg/L. Fe+2) occurs. Under oxidizing This standard is not based on human conditions, ferric iron (FeIII or Fe3+) health effects. Iron stains plumbing dominates. Concentrations of ferrous fixtures and clothing. The SMCL is iron in ground or surface water may be based on the concentration of dissolved more than 1 mg/L (part per million). iron in ground water. Ferric iron, although relatively insoluble, forms complexes with other chemicals or How is iron distributed in Minnesota with suspended material. ground water? Iron exceeded the SMCL of 0.30 mg/L What are sources of iron in ground in about 70 percent of the wells sampled water? in the Ground Water Monitoring and Most iron in Minnesota’s ground water Assessment Program (GWMAP) occurs naturally. Iron exists at high statewide baseline network of 954 wells. concentrations in many types of rocks. The concentration of dissolved iron will Concentrations may be as high as 40,000 be smaller since samples were not mg/kg (parts per million) in igneous filtered. -
The Influence of Heavy Metals and Organic Matter on Hexavalent
View metadata, citation and similar papers at core.ac.uk brought to you by CORE provided by Archivio della ricerca- Università di Roma La Sapienza 289 A publication of CHEMICAL ENGINEERING TRANSACTIONS VOL. 47, 2016 The Italian Association of Chemical Engineering Online at www.aidic.it/cet Guest Editors: Angelo Chianese, Luca Di Palma, Elisabetta Petrucci, Marco Stoller Copyright © 2016, AIDIC Servizi S.r.l., ISBN 978-88-95608-38-9; ISSN 2283-9216 DOI: 10.3303/CET1647049 The Influence of Heavy Metals and Organic Matter on Hexavalent Chromium Reduction by Nano Zero Valent Iron in Soil Mouhamadou Thierno Gueyea, Luca Di Palmab, Gunel Allahverdeyevac, Irene b b b b Bavasso , Elisabetta Petrucci , Marco Stoller , Giorgio Vilardi a Université Cheikh Anta Diop de Dakar (UCAD), Dakar Fann, Senegal b Sapienza Università di Roma, Dipartimento di Ingegneria Chimica Materiali Ambiente, via Eudossiana 18, 00184 Roma c Baku State University, 23 Khalilov St., Baku, Azerbaijan During the last decades great attention has been payed at evaluating the feasibility of Cr(VI) reduction in soil 0 by nano zero valent iron (nZVI). An inhibitory effect on the Cr(VI) reduction by Fe nanoparticles is generally shown in the presence of high level of heavy metals and natural organic matter in soil. Heavy metals in the environment can react with nZVI by redox reactions, precipitation/dissolution reactions, and adsorption/desorption phenomena. As a result of the presence of metals as Ni, Pb, a decrease in the rate of Cr(VI) reduction was observed. Hence, in the present study, experimental tests of Cr(VI) reduction by nZVI in the presence of selected heavy metals, such as nickel and lead, and in the presence of high level of organic matter, are presented and discussed. -
Periodic Table 1 Periodic Table
Periodic table 1 Periodic table This article is about the table used in chemistry. For other uses, see Periodic table (disambiguation). The periodic table is a tabular arrangement of the chemical elements, organized on the basis of their atomic numbers (numbers of protons in the nucleus), electron configurations , and recurring chemical properties. Elements are presented in order of increasing atomic number, which is typically listed with the chemical symbol in each box. The standard form of the table consists of a grid of elements laid out in 18 columns and 7 Standard 18-column form of the periodic table. For the color legend, see section Layout, rows, with a double row of elements under the larger table. below that. The table can also be deconstructed into four rectangular blocks: the s-block to the left, the p-block to the right, the d-block in the middle, and the f-block below that. The rows of the table are called periods; the columns are called groups, with some of these having names such as halogens or noble gases. Since, by definition, a periodic table incorporates recurring trends, any such table can be used to derive relationships between the properties of the elements and predict the properties of new, yet to be discovered or synthesized, elements. As a result, a periodic table—whether in the standard form or some other variant—provides a useful framework for analyzing chemical behavior, and such tables are widely used in chemistry and other sciences. Although precursors exist, Dmitri Mendeleev is generally credited with the publication, in 1869, of the first widely recognized periodic table.