The Periodic Table of the Chemical Elements
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Treatment Outcome Following Use of the Erbium, Chromium:Yttrium
Treatment outcome following use IN BRIEF • Highlights that successful treatment RESEARCH of peri-implantitis is unpredictable and of the erbium, chromium:yttrium, usually involves the need for surgery. • Outlines a minimalistic treatment approach for peri-implantitis with promising results after six months. scandium, gallium, garnet laser • Suggests that the protocol described may be of use in a pilot study or controlled in the non-surgical management clinical trial. of peri-implantitis: a case series R. Al-Falaki,*1 M. Cronshaw2 and F. J. Hughes3 VERIFIABLE CPD PAPER Aim To date there is no consensus on the appropriate usage of lasers in the management of peri-implantitis. Our aim was to conduct a retrospective clinical analysis of a case series of implants treated using an erbium, chromium:yttrium, scandium, gallium, garnet laser. Materials and methods Twenty-eight implants with peri-implantitis in 11 patients were treated with an Er,Cr:YSGG laser (68 sites >4 mm), using a 14 mm, 500 μm diameter, 60º (85%) radial firing tip (1.5 W, 30 Hz, short (140 μs) pulse, 50 mJ/pulse, 50% water, 40% air). Probing depths were recorded at baseline after 2 months and 6 months, along with the presence of bleeding on probing. Results The age range was 27-69 years (mean 55.9); mean pocket depth at baseline was 6.64 ± SD 1.48 mm (range 5-12 mm),with a mean residual depth of 3.29 ± 1.02 mm (range 1-6 mm) after 2 months, and 2.97 ± 0.7 mm (range 1-9 mm) at 6 months. -
Selenium and Tellurium in 2017
2017 Minerals Yearbook SELENIUM AND TELLURIUM [ADVANCE RELEASE] U.S. Department of the Interior May 2020 U.S. Geological Survey Selenium and Tellurium By C. Schuyler Anderson Domestic survey data and tables were prepared by Robin C. Kaiser, statistical assistant. In 2017, selenium and tellurium were not refined in the selenium dioxide (SeO2) was substituted for sulfur dioxide United States. Three copper refineries produced either to reduce the power required to operate electrolytic cells. In semirefined selenium and tellurium or selenium- and tellurium- 2017, global production of manganese increased by 37% to containing copper anode slimes, and all production was 1.73 million metric tons, of which China remained the main exported for further processing. U.S. imports and exports producer (International Manganese Institute, 2018, p. 17). of selenium and tellurium increased in 2017 compared with In other metallurgical applications, selenium was used with those in 2016. The average Platts Metals Week New York bismuth to substitute for lead as a free-machining agent in brass dealer price for 99.5%-pure selenium in 2017 decreased by plumbing fixtures. Metallurgical-grade selenium also was used 54% to $10.78 per pound from $23.69 per pound in 2016, as an additive to cast iron, copper, lead, and steel alloys. reaching the lowest price since 2003. The average price for In the glass industry, selenium was used to decolorize the 99.99%-pure tellurium (in warehouse, Rotterdam), as reported green tint caused by iron impurities in container glass and other by Argus Media group—Argus Metals International, increased soda-lime silica glass. -
Evolution and Understanding of the D-Block Elements in the Periodic Table Cite This: Dalton Trans., 2019, 48, 9408 Edwin C
Dalton Transactions View Article Online PERSPECTIVE View Journal | View Issue Evolution and understanding of the d-block elements in the periodic table Cite this: Dalton Trans., 2019, 48, 9408 Edwin C. Constable Received 20th February 2019, The d-block elements have played an essential role in the development of our present understanding of Accepted 6th March 2019 chemistry and in the evolution of the periodic table. On the occasion of the sesquicentenniel of the dis- DOI: 10.1039/c9dt00765b covery of the periodic table by Mendeleev, it is appropriate to look at how these metals have influenced rsc.li/dalton our understanding of periodicity and the relationships between elements. Introduction and periodic tables concerning objects as diverse as fruit, veg- etables, beer, cartoon characters, and superheroes abound in In the year 2019 we celebrate the sesquicentennial of the publi- our connected world.7 Creative Commons Attribution-NonCommercial 3.0 Unported Licence. cation of the first modern form of the periodic table by In the commonly encountered medium or long forms of Mendeleev (alternatively transliterated as Mendelejew, the periodic table, the central portion is occupied by the Mendelejeff, Mendeléeff, and Mendeléyev from the Cyrillic d-block elements, commonly known as the transition elements ).1 The periodic table lies at the core of our under- or transition metals. These elements have played a critical rôle standing of the properties of, and the relationships between, in our understanding of modern chemistry and have proved to the 118 elements currently known (Fig. 1).2 A chemist can look be the touchstones for many theories of valence and bonding. -
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Recent IUPAC technical reports and recommendations that aff ect the many fi elds of pure and applied chemistry. Making an imPACt See also www.iupac.org/what-we-do/journals/ Standard Atomic Weight of Hafnium elements. For example, radioactive decay of lutetium Revised alters the isotopic composition of hafnium by produc- ing the light isotope of hafnium-176. Thus, some rare The IUPAC Com- terrestrial materials can have abnormal isotopic com- mission on Isotopic positions of hafnium with the most extreme known Abundances and case being sedimentary chert from South Africa hav- Atomic Weights ing atomic-weight value of 178.447. (CIAAW) met under The CIAAW continues to evaluate literature data the chairmanship of which leads to identifi cation of developments in the Dr. Juris Meija (Can- measurement science, recognition of new discover- ada), at the Federal ies, and remains committed to modernize its technical Institute for Mate- guidelines and work towards further expansion of its rials Research and website to include more historical databases. These Testing (bam.de), changes and considerations will be published in Pure Berlin Germany, in and Applied Chemistry [2] and can be found online at June 2019. As IUPAC celebrates its centennial in 2019, the website of The CIAAW (ciaaw.org). its oldest body, the CIAAW, turns 120 with its beginnings tracing back to Berlin in 1899 [1]. Following its 2019 Notes meeting, the CIAAW recommended changes to the stan- 1. For a historical account of the CIAAW, see J.R. De dard atomic weight (i.e. relative atomic mass) of hafnium Laeter and J. -
The Periodic Electronegativity Table
The Periodic Electronegativity Table Jan C. A. Boeyens Unit for Advanced Study, University of Pretoria, South Africa Reprint requests to J. C. A. Boeyens. E-mail: [email protected] Z. Naturforsch. 2008, 63b, 199 – 209; received October 16, 2007 The origins and development of the electronegativity concept as an empirical construct are briefly examined, emphasizing the confusion that exists over the appropriate units in which to express this quantity. It is shown how to relate the most reliable of the empirical scales to the theoretical definition of electronegativity in terms of the quantum potential and ionization radius of the atomic valence state. The theory reflects not only the periodicity of the empirical scales, but also accounts for the related thermochemical data and serves as a basis for the calculation of interatomic interaction within molecules. The intuitive theory that relates electronegativity to the average of ionization energy and electron affinity is elucidated for the first time and used to estimate the electron affinities of those elements for which no experimental measurement is possible. Key words: Valence State, Quantum Potential, Ionization Radius Introduction electronegative elements used to be distinguished tra- ditionally [1]. Electronegativity, apart from being the most useful This theoretical notion, in one form or the other, has theoretical concept that guides the practising chemist, survived into the present, where, as will be shown, it is also the most bothersome to quantify from first prin- provides a precise definition of electronegativity. Elec- ciples. In historical context the concept developed in a tronegativity scales that fail to reflect the periodicity of natural way from the early distinction between antag- the L-M curve will be considered inappropriate. -
Inorganic Selenium and Tellurium Speciation in Aqueous Medium of Biological Samples
1 INORGANIC SELENIUM AND TELLURIUM SPECIATION IN AQUEOUS MEDIUM OF BIOLOGICAL SAMPLES ________________________ A Thesis Presented to The Faculty of the Department of Chemistry Sam Houston State University ________________________ In Partial fulfillment Of the Requirements for the Degree of Master of Science ________________________ by Rukma S. T. Basnayake December, 2001 2 INORGANIC SELENIUM AND TELLURIUM SPECIATION IN AQUEOUS MEDIUM OF BIOLOGICAL SAMPLES by Rukma S.T. Basnayake _______________________________ APPROVED: ________________________________ Thomas G. Chasteen, Thesis Director ________________________________ Paul A. Loeffler ________________________________ Benny E. Arney Jr. APPROVED: _____________________________ Dr. Brian Chapman, Dean College of Arts and Sciences 3 ABSTRACT Basnayake, Rukma ST, Inorganic Selenium and Tellurium Speciation in Aqueous Medium of Biological Samples, Master of Science (Chemistry), December 2001, Sam Houston State University, Huntsville, Texas, 60 pp. Purpose The purpose of this research was to develop methods to study the ability of bacteria, Pseudomonas fluorescens K27 to detoxify tellurium and selenium salts by biotransformation processes under anaerobic conditions. Another purpose was to make an effort to separate biologically produced Se0 from cells. Methods Pseudomonas fluorescens K27 was grown in TSN3 medium (tryptic soy broth with 0.3% nitrate) under anaerobic conditions and the production of elemental tellurium and elemental selenium was observed when amended with inorganic tellurium salts and selenium salts, respectively. The amount of soluble tellurium species in the culture medium also was determined. Samples from a 2.75 L bioreactor were taken after cultures had reached the stationary growth phase and were centrifuged in order to separate insoluble species (elemental tellurium, elemental selenium) from soluble species (oxyanions of tellurium, oxyanions of selenium). -
An Alternate Graphical Representation of Periodic Table of Chemical Elements Mohd Abubakr1, Microsoft India (R&D) Pvt
An Alternate Graphical Representation of Periodic table of Chemical Elements Mohd Abubakr1, Microsoft India (R&D) Pvt. Ltd, Hyderabad, India. [email protected] Abstract Periodic table of chemical elements symbolizes an elegant graphical representation of symmetry at atomic level and provides an overview on arrangement of electrons. It started merely as tabular representation of chemical elements, later got strengthened with quantum mechanical description of atomic structure and recent studies have revealed that periodic table can be formulated using SO(4,2) SU(2) group. IUPAC, the governing body in Chemistry, doesn‟t approve any periodic table as a standard periodic table. The only specific recommendation provided by IUPAC is that the periodic table should follow the 1 to 18 group numbering. In this technical paper, we describe a new graphical representation of periodic table, referred as „Circular form of Periodic table‟. The advantages of circular form of periodic table over other representations are discussed along with a brief discussion on history of periodic tables. 1. Introduction The profoundness of inherent symmetry in nature can be seen at different depths of atomic scales. Periodic table symbolizes one such elegant symmetry existing within the atomic structure of chemical elements. This so called „symmetry‟ within the atomic structures has been widely studied from different prospects and over the last hundreds years more than 700 different graphical representations of Periodic tables have emerged [1]. Each graphical representation of chemical elements attempted to portray certain symmetries in form of columns, rows, spirals, dimensions etc. Out of all the graphical representations, the rectangular form of periodic table (also referred as Long form of periodic table or Modern periodic table) has gained wide acceptance. -
Indium, Caesium Or Cerium Compounds for Treatment of Cerebral Disorders
Europaisches Patentamt 298 644 J European Patent Office Oy Publication number: 0 A3 Office europeen des brevets EUROPEAN PATENT APPLICATION © Application number: 88305895.0 © intci.s A61K 31/20, A61K 31/28, A61K 33/24 @ Date of filing: 29.06.88 © Priority: 07.07.87 GB 8715914 © Applicant: EFAMOL HOLDINGS PLC Efamol House Woodbridge Meadows © Date of publication of application: Guildford Surrey GU1 1BA(GB) 11.01.89 Bulletin 89/02 @ Inventor: Horrobin, David Frederick © Designated Contracting States: c/o Efamol House Woodbridge Meadows AT BE CH DE ES FR GB GR IT LI LU NL SE Guildford Surrey GU1 1BA(GB) Inventor: Corrigan, Frank ® Date of deferred publication of the search report: c/o Argyll & Bute Hospital 14.11.90 Bulletin 90/46 Lochgilphead, Argyll PA3T 8ED Scotland(GB) © Representative: Caro, William Egerton et al J. MILLER & CO. Lincoln House 296-302 High Holborn London WC1V 7 JH(GB) © Indium, caesium or cerium compounds for treatment of cerebral disorders. © A method of treatment of schizophrenia or other chronic cerebral disorder in which cerebral atrophy is shown, is characterised in that one or more as- similable or pharmaceutically acceptable indium caesium or cerium compounds is associated with a pharmaceutically acceptable diluent or carrier. CO < CD 00 O> Xerox Copy Centre PARTIAL EUROPEAN SEARCH REPORT Application number European Patent J which under Rule 45 of the European Patent Convention Office shall be considered, for the purposes of subsequent EP 88 30 5895 proceedings, as the European search report DOCUMENTS CONSIDERED TO BE RELEVANT Citation of document with indication, where appropriate, Relevant CLASSIFICATION OF THE ategory of relevant passages to claim APPLICATION (Int. -
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 -
The Development of the Periodic Table and Its Consequences Citation: J
Firenze University Press www.fupress.com/substantia The Development of the Periodic Table and its Consequences Citation: J. Emsley (2019) The Devel- opment of the Periodic Table and its Consequences. Substantia 3(2) Suppl. 5: 15-27. doi: 10.13128/Substantia-297 John Emsley Copyright: © 2019 J. Emsley. This is Alameda Lodge, 23a Alameda Road, Ampthill, MK45 2LA, UK an open access, peer-reviewed article E-mail: [email protected] published by Firenze University Press (http://www.fupress.com/substantia) and distributed under the terms of the Abstract. Chemistry is fortunate among the sciences in having an icon that is instant- Creative Commons Attribution License, ly recognisable around the world: the periodic table. The United Nations has deemed which permits unrestricted use, distri- 2019 to be the International Year of the Periodic Table, in commemoration of the 150th bution, and reproduction in any medi- anniversary of the first paper in which it appeared. That had been written by a Russian um, provided the original author and chemist, Dmitri Mendeleev, and was published in May 1869. Since then, there have source are credited. been many versions of the table, but one format has come to be the most widely used Data Availability Statement: All rel- and is to be seen everywhere. The route to this preferred form of the table makes an evant data are within the paper and its interesting story. Supporting Information files. Keywords. Periodic table, Mendeleev, Newlands, Deming, Seaborg. Competing Interests: The Author(s) declare(s) no conflict of interest. INTRODUCTION There are hundreds of periodic tables but the one that is widely repro- duced has the approval of the International Union of Pure and Applied Chemistry (IUPAC) and is shown in Fig.1. -
Dmitri Mendeleev
DOWNLOADABLE EXTRAS Atomic Structure: Part 1 1 Dmitri Mendeleev Dmitri Mendeleev was born on the 8th of February 1834 in Siberia, Russia. His father who was a teacher of the arts and politics, died when he was only thirteen. He was one of a large family and is thought to possibly have had 17 brothers and sisters. Due to his father’s death and a failed family business (a glass factory that burnt down) the family were very poor. Despite this, his mother wanted him to be educated at a higher level so she moved the family to St Petersburg in order for Dmitri to attend school. After graduating he became a teacher in the area of science. His passion was chemistry and he studied the capillarity of liquids (ability of a liquid to fl ow in a narrow space without any suction or pumping, like when water moves against gravity up a straw placed in a glass of water), the components of petrol and the spectroscope (a device that uses light to identify unknown materials). Because chemistry at the time was so disorganised, Mendeleev saw a need to establish a set of rules and guidelines that would be universal (able to be used across the world). He started by writing two very successful text books that included all of his chemistry knowledge. However he felt that this wasn’t enough and that the concepts of chemistry were too broad and unlinked. In 1869 he started to write a system that ordered the elements as these were the main concept behind a lot of other chemistry. -
The Infrared Spectrum of Indium in Silicon Revisited A
The infrared spectrum of indium in silicon revisited A. Tardella, B. Pajot To cite this version: A. Tardella, B. Pajot. The infrared spectrum of indium in silicon revisited. Journal de Physique, 1982, 43 (12), pp.1789-1795. 10.1051/jphys:0198200430120178900. jpa-00209562 HAL Id: jpa-00209562 https://hal.archives-ouvertes.fr/jpa-00209562 Submitted on 1 Jan 1982 HAL is a multi-disciplinary open access L’archive ouverte pluridisciplinaire HAL, est archive for the deposit and dissemination of sci- destinée au dépôt et à la diffusion de documents entific research documents, whether they are pub- scientifiques de niveau recherche, publiés ou non, lished or not. The documents may come from émanant des établissements d’enseignement et de teaching and research institutions in France or recherche français ou étrangers, des laboratoires abroad, or from public or private research centers. publics ou privés. J. Physique 43 (1982) 1789-1795 DTCEMBRE 1982, 1789 Classification Physics Abstracts 71.55 - 78.50 The infrared spectrum of indium in silicon revisited A. Tardella and B. Pajot Groupe de Physique des Solides de l’Ecole Normale Supérieure, Université Paris VII, Tour 23, 2, place Jussieu, 75251 Paris Cedex 05, France (Reçu le 27 mai 1982, révisé le 22 juillet, accepté le 23 août 1982) Résumé. 2014 Le spectre d’absorption de l’indium dans le silicium a été mesuré dans des conditions où l’élargisse- ment des raies par effet de concentration est négligeable. Avec une résolution appropriée, on détecte 17 transitions et les composantes d’un doublet serré sont attribuées à deux transitions calculées. A 6 K, la largeur intrinsèque des raies varie de 2,6 à 0,8 cm-1, ce qui indique un effet lié à la structure de la bande de valence du silicium.