DOCSLIB.ORG

Elena HELEREA Marius Daniel CĂLIN

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Elena HELEREA Marius Daniel CĂLIN Elena HELEREA Marius Daniel CĂLIN 2015 ISBN 978–606–19–0717–5 FOREWORD A necessity and support In the last few years, many Electrical Engineering, Science of Materials and Physics Departments looked for a manual about materials and devices at the undergraduate/ graduate level that covers a broad spectrum of electrical and electronic materials, including highly conductive materials, semiconductors, dielectrics and magnetic materials. It was necessary to have applications and extensive problems, to include elementary quantum mechanics, to satisfy various accreditation requirements across international borders. The present work answers this need, and since 2002, it has become a textbook in Transilvania University of Braşov and a number of higher schools from Braşov area. The text-book represents a first course in electrical engineering materials and devices – in English language - suitable for a one- or two-semester course in materials for electrical and electronic engineering at undergraduate level. It would also be useful as graduate introductory course in materials for electrical engineering and material scientists. The course intends to be a reference material for the teachers who approach electrical technologies and engineering issues. The present support of course is an improved text-book, which was developed in the frame of VIRTUAL-ELECTR_LAB project – a Leonardo Project, to sustain the innovative approach for improvement of the teaching-learning-evaluation methods using e-resources, in which the knowledge are gradually transferred, on three levels: beginner, intermediate and advanced, and the visualization and explanation of the phenomena through ICT tools allow a correct and deep understanding, consequently the obtaining of a high level knowledge for the trainees. Organization and Features The course, structured on three study-levels, has as main objective the acquisition of knowledge and the formation of skills concerning the handling of the multifunctional materials used in electrical engineering and technology. The quality and characteristics of the materials are presented in relation to the factors, which influence them, so that the user could adjust the matrix of demands imposed by the electrical or electronic systems and the matrix of the material parameters. For a better access to the structure of the text-book, at the beginning of each sub- chapter, the symbol for the study-level is marked: Beginner level Intermediate level Advanced level Beginner level On the basic level there are to be treated the following issues: the functions/the roles of different classes of materials (conductors, semi-conductors, electro- insulators, dielectrics, magnetic materials); testing methods; characteristic features; examples of specific applications. Intermediate level On the intermediate level are to be treated: functions of materials and justification by means of classic microscopic theories; the testing methods by specifying the particularities of the measuring cells and measuring devices used; justifying the characteristic features; examples of applications of the materials, also considering the technological and environmental implications. Advanced level On the advanced level are to be treated: the characteristic parameters and justification by means of appropriate theories; testing the materials and considering the measurement errors and the factors which influence them; simulating the behaviour of the materials under various circumstances of functioning; some applications which take into account the technical, technological and environmental implications. The textbook has 5 chapters which provide an overview on material laws in electrotechnics (Ch. 1), conductive materials (Ch. 2), semiconductive materials (Ch. 3), dielectrics (Ch. 4), magnetic materials (Ch. 5), a section of assessment with questions and solutions for each chapter, and reach references. The present textbook added new concepts and applications on this fascinate world of materials for electric and electronic engineering. Acknowledgments Our thanks to the graduate students, especially Dorian Popovici, who contributed to the designing the explicative figures, and to teachers Mariana Streza, Ana Maria Antal and Viviana Moldovan, who read various portions at the manuscript and provided valuable solutions for English translation of the text. The Authors, Braşov, Autumn, 2015. 4 Materials in Electrical Engineering 1.1. DEFINITIONS AND CLASSIFICATIONS 1.1.1. Definitions. Material Parameters A large number of substances and materials are used in electrical engineering. The notion substance includes the category of objects that are characterized by the homogeneity of the composition and of their constituent structure. Examples: water, paper, air, iron etc. The notion material is much wider and includes the objects of different or resembling nature and structure that are used in a certain domain. We may consider the material as a whole made up of one or more substances. Examples: plastics, stratified materials, composites, ferrites. Many branches of science study the materials. Thus, among these sciences, chemistry and physics give an image/explanation of the composition (the nature of constituent particles), of the structure (the way the constituent particles are arranged) and of the physical and chemical properties of substances. Among applied sciences, the science of materials studies the composition and the structure as well as the properties of materials used in certain domains (car industry, electrotechnics, wood industry etc.). The material engineering science studies the structure, the producing and processing of materials, their properties and performances. Before making any classifications, we need a distinction between the notions of material property and material parameter. A material property represents a common characteristic for the specific class of materials that characterize the response of the material to the action of external stresses. Examples: Electrical conductivity defines the way a material behaves when an electric field is applied (the material property of conducting the electric current); Magnetic susceptivity characterizes the behavior of the material when a magnetic field is applied etc. For every material property is associated a physical quantity (which can be scalar, vector, tensor) called material parameter, which characterizes the material state under external stress. Examples: Electrical conductivity σ is a material parameter that characterizes the property of electric conduction; 1..Parameters and Material Laws in Electrical Engineering 5 Electrical susceptivity ϰ is a material parameter that characterizes the property of electrical polarization of dielectrics; Melting temperature Ttop is a material parameter that characterizes the property of fusibility (the property of the material to melt); etc. 1.1.2. Classification of Materials Materials can be classified on different criteria. A. According to their composition, there are: Organic materials, which contain carbon, are obtained from the vegetal or animal kingdom (examples: paper, wood, resins, rubber, etc.); Inorganic materials, which don’t contain carbon, are obtained from the mineral kingdom (examples: salts, acids, bases, glass, asbestos, etc.). B. According to the character of the periodical properties of the chemical elements: metals, metalloids and non-metals. Their characteristics are presented in the Table 1.1. Table 1.1. The comparative properties of metals, metalloids and non-metals. Properties Metals Metalloids Non-metals Electronegativity 0.7 – 1.8 1.8 – 2.2 2.2 – 4.0 Electric conductivity High Medium Low Increases with Decreases with Is little influenced by Electric resistance the rise of the rise of the temperature temperature temperature Malleable, Neither malleable Mechanical properties Flawed Ductile nor ductile Notes: Electronegativity is the property and a criterion of appreciation of the capacity to attract electrons by an atom from a molecule or from a complex structure; Malleability is the property of a metal to be drawn into leaves; Ductility is the property of a metal to be drawn into wires. C. According to their state of aggregation and their structure, there are: Gaseous materials, which have no proper form or volume (examples: air, nitrogen, methane gas, etc.); Liquid materials, they have a proper form, but no proper volume (examples: oils, water in liquid state, etc.); Solid materials, which have proper form and volume and a specific structure, therefore we can be distinguished: 6 Materials in Electrical Engineering Crystalline materials, which present regularity at long distance of the constituent atoms (examples: metals, silicon, germanium, quartz, etc.); Amorphous materials, which present only regularity at short distance of the constituent atoms (examples: resins, plastics, rubber, porcelain, etc.); Mezomorphous materials, which present the crystalline state only at certain temperature and concentration conditions (examples: liquid crystals, etc.). D. According to a characteristic property, such as: The electrical conductivity: o Electrical conductive materials, which allow the passing of intense electric currents, of A - kA order (examples: silver, copper, gold, aluminum, graphite, etc.); o Semiconductive materials, which allow the passing of the low electric current, of µA – mA order (examples: germanium and silicon crystals with impurities, etc.); o Electroinsulating materials, where the electric currents of conduction
Load more

Recommended publications
  • Plagioclase-Spinel-Graphite Xenoliths in Metallic Iron
    THE AMERICAN MINERALOGIST, VOL. 51, MAY_JUNE, 1966 PLAGIOCLASE-SPINEL-GRAPHITEXENOLITHS IN METALLIC IRON-BEARING BASALTS, DISKO ISLAND, GREENLAND Wrr,rrau G. MBr.soNeNo Gnoncp Swrrzrn Departmentof Mineral Sciences, U. S. l{ational Museum,Washington, D. C. Ansrnac:t Tertiary basalt flows from west Greenland commonly contain metallic iron and graph- ite. They are thus some of the most reduced of terrestrial basalts, and are of interest in con- nection with basalt studies in general, and in connection with the origin of certain meteor- ites (Lovering, 1964). Xenoliths composed mainly of plagioclase (Anzo-zu), graphite, rose-colored spinel and rarely corundum are included in these basalts on Disko Island. The xenoliths are remark- ably similar to reconstituted shale xenoliths in basaltic rocks from other localities except for the presence oI graphite and in the composition of the spinel. The spinel has n:1.747 +0.001, o:8'119+0.002 and D:3.81 +0.01, and electron microprobe analysis gave Mg : 13 and Fe:8.9/6. These data indicate a spinel with composition about spzaHezz.This un- usually low Fe content compared to spinels from other aluminous xenoliths in basaltic rocks is evidently related to the low oxygen fugacities ln basaltic magmas in contact with graphite, particularly in an environment such as Disko, where active reduction of ferrous iron to iron evidently occurred. The close similarities in the mineralogy of the xenoliths from specimen to specimen indi- cate complete equilibration of magma and xenoliths. This equilibration involved mainly loss of K and Si, and gain of Ca, Mg, Al and Na by the xeno.liths.
    [Show full text]
  • NEPHELINE SYENITE and IRON ORE DEPOSITS in GREENLAND by Richardbogvad*
    NEPHELINE SYENITE AND IRON ORE DEPOSITS IN GREENLAND By RichardBogvad* HE voyages of exploration toGreenland at the beginning of the Tseventeenth century aroused interestin the possibilities of mineral wealth in the country. As a result King Christian IV in 1605 and 1606 equipped two expeditions to collect silver, which was supposed to have been found in large quantities, but only valueless mica was brought home. After this disappointment thematter was allowed to rest for barely a century,when fresh investigations werestarted; these have-sometimes withlong intervals-been continueduntil today (2; 4). Much time has been devoted tothe investigation of copperand graphite occurrences; coal (lignite) has been mined fortwo centuries, andmarble has been quarried. But so farthe only mineral foundwhich can be profitablv minedis cryolitefrom Ivigtut. Recently, however, nepheline syenite and iron ore deposits have been investigated. NEPHELINESYENITE In GreenlandIn nepheline syenite' occurs in the Kangerd- lugssuaq district onthe east coast (18, p. 38; 19, p. 41); be- tween the Arsuk and Ika fjords onthe west coast (17, p. 387; 6) ; and between Julianehaab and Kagssiarssuk in southern Green- land (15, p. 35; 16, p. 132; 17; 20, p. 60). Only inthe last- mentioneddistrict, which can be divided into the Igdlerfigsalik and Ilimausak-Kangerdluarsuk massifs, are there large quantities of thezirconium-bearing min- eral eudialyte'. K. L. Giesecke (1 O), who made the first sys- tematic mineralogical investiga- tion of Greenlandfrom 1806 to 1813, visited the deposits in Fig. 1. the Kangerdluarsuk district but ~ "Chief geologist, Kryolitselskabet Oresund A/S (The Cryolite Company), Copenhagen. 'Igneous rocks characterized by thepredominance of alkalifelspar, and nephelite, NaAlSiO,.
    [Show full text]
  • The Question of Meteoritic Versus Smelted Nickel-Rich Iron: Archaeological Evidence and Experimental Results Author(S): E
    The Question of Meteoritic versus Smelted Nickel-Rich Iron: Archaeological Evidence and Experimental Results Author(s): E. Photos Source: World Archaeology, Vol. 20, No. 3, Archaeometallurgy (Feb., 1989), pp. 403-421 Published by: Taylor & Francis, Ltd. Stable URL: http://www.jstor.org/stable/124562 Accessed: 23/08/2009 02:54 Your use of the JSTOR archive indicates your acceptance of JSTOR's Terms and Conditions of Use, available at http://www.jstor.org/page/info/about/policies/terms.jsp. JSTOR's Terms and Conditions of Use provides, in part, that unless you have obtained prior permission, you may not download an entire issue of a journal or multiple copies of articles, and you may use content in the JSTOR archive only for your personal, non-commercial use. Please contact the publisher regarding any further use of this work. Publisher contact information may be obtained at http://www.jstor.org/action/showPublisher?publisherCode=taylorfrancis. Each copy of any part of a JSTOR transmission must contain the same copyright notice that appears on the screen or printed page of such transmission. JSTOR is a not-for-profit organization founded in 1995 to build trusted digital archives for scholarship. We work with the scholarly community to preserve their work and the materials they rely upon, and to build a common research platform that promotes the discovery and use of these resources. For more information about JSTOR, please contact [email protected]. Taylor & Francis, Ltd. is collaborating with JSTOR to digitize, preserve and extend access to World Archaeology. http://www.jstor.org The question of meteoritic versus smelted nickel-rich iron: archaeological evidence and experimental results E.
    [Show full text]
  • Metals from Ores: an Introduction
    CRIMSONpublishers http://www.crimsonpublishers.com Mini Review Aspects Min Miner Sci ISSN 2578-0255 Metals from Ores: An Introduction Fathi Habashi* Department of Mining, Laval University, Canada *Corresponding author: Fathi Habashi, Department of Mining, Metallurgical and Materials Engineering, Laval University, Quebec City, Canada Submission: October 09, 2017; Published: December 11, 2017 Introduction of metallic lustre. Of these about 300 are used industrially in the chemical industry, in building materials, in fertilizers, as fuels, etc., chemical composition, constant physical properties, and a A mineral is a naturally occurring substance having a definite characteristic crystalline form. Ores are a mixture of minerals: they are processed to yield an industrial mineral or treated chemically and are known as the industrial minerals Figure 3. to yield a single or several metals. Ores that are generally processed for only a single metal are those of iron, aluminium, chromium, tin, mercury, manganese, tungsten, and some ores of copper. Gold ores may yield only gold, but silver is a common associate. Nickel ores are always associated with cobalt, while lead and zinc always occur together in ores. All other ores are complex yielding a number of metals. before being treated by chemical methods to recover the metals. Ores undergo a beneficiation process by physical methods and grinding then separation of the individual mineral by physical Figure 2: Metals and metalloids obtained from ores. Beneficiation processes involve liberation of minerals by crushing methods (gravity, magnetic, etc.) or physicochemical methods pyrometallurgical, and electrochemical methods. Metals and (flotation) Figure 1. Chemical methods involve hydrometallurgical, metalloids obtained from ores are shown in Figure 2.
    [Show full text]
  • CMLC Newsletter Feb 2020
    1 FEBRUARY 2020 EDITION No Stone Unturned silver platinum WHAT DO ALL OF THESE gold Native iron WELL KNOWN METALS They are all “native palladium metals” that is metal ele- HAVE IN ments that have not bonded with other elements. COMMON? In the next two editions of “No Stone Unturned”, each of these, along with other native elements will be examined. 2 WE WISH TO THANK THE FEDERAL MEMBER CONTACT INFORMATION: FOR LEICHHARDT, HON. WARREN ENTSCH, Phone: 0450 185 250 FOR FACILITATING THE PRINTING OF THIS Email: [email protected] MAGAZINE. Postal Address: PO Box 389, Westcourt. 4870. NQ 129 Mulgrave Road (in the Youth Centre Grounds) CLUB HOURS: MANAGEMENT COMMITTEE MEMBERS: Monday 4:00pm to 9:30 pm President: Michael Hardcastle Vice-president: Mike Rashleigh Wednesday *8:30am to 12:30 Secretary: Jan Hannam *1:00pm to 4:00pm Treasurer: Joe Venables Saturday *9:00am to 1:00 Assistant Secretary: Allan Rose Assistant Treasurer: Richie Williams *12:00pm to 4:00pm Extra Members MC: Tammi Saal Workroom fees are $4 per session or part OTHER PERSONNEL: thereof and must be paid before session begins. Purchasing Officer: Jan Saal Specimen Curator: David Croft The Club provides tuition in cabbing, faceting, Specimen Testers: David Croft, Vic Lahtinen, silver-smithing and lost wax casting Trevor Hannam GENERAL MEETINGS: Cabochon Advisors: Jodi Sawyer Faceting Instructors: Jim Lidstone, Joe Ferk, General meetings are held on the 1st Saturday of Trevor Hannam each month. When this is a public holiday, the Silver Instructors: Sylvia Rose, Jan Saal meeting is deferred until the following Saturday. Machinery Curators: volunteers needed Note: Your Attendance at General Meetings Gem Testing: Vic Lahtinen, Trevor Hannam ensures that your voice will be heard when it comes Librarian: David Croft to making decisions concerning the running of the Facebook Admin: Tammi Saal, Peggy Walker club.
    [Show full text]
  • BUCHWALD, Vagn Fabritius, 2001, Ancient Iron and Slags in Greenland, Meddelelser Om Grønland: Man & Society, 26, 92 Pages
    Document generated on 09/27/2021 3:36 a.m. Études/Inuit/Studies BUCHWALD, Vagn Fabritius, 2001, Ancient Iron and Slags in Greenland, Meddelelser om Grønland: Man & Society, 26, 92 pages. Illustrated. Lynda Gullason Architecture paléoesquimaude Palaeoeskimo Architecture Volume 27, Number 1-2, 2003 URI: https://id.erudit.org/iderudit/010816ar DOI: https://doi.org/10.7202/010816ar See table of contents Publisher(s) Association Inuksiutiit Katimajiit Inc. ISSN 0701-1008 (print) 1708-5268 (digital) Explore this journal Cite this review Gullason, L. (2003). Review of [BUCHWALD, Vagn Fabritius, 2001, Ancient Iron and Slags in Greenland, Meddelelser om Grønland: Man & Society, 26, 92 pages. Illustrated.] Études/Inuit/Studies, 27(1-2), 517–521. https://doi.org/10.7202/010816ar Tous droits réservés © La revue Études/Inuit/Studies, 2003 This document is protected by copyright law. Use of the services of Érudit (including reproduction) is subject to its terms and conditions, which can be viewed online. https://apropos.erudit.org/en/users/policy-on-use/ This article is disseminated and preserved by Érudit. Érudit is a non-profit inter-university consortium of the Université de Montréal, Université Laval, and the Université du Québec à Montréal. Its mission is to promote and disseminate research. https://www.erudit.org/en/ industrial nations with new territories and indigenous populations." Those with an interest in colonial history will find this book useful for there are obvious underlying similarities to the events in the north that can be readily compared with Mead's, Said's and other scholars' exotic warm locals. Analytical comparisons of centre and periphery, indigenous peoples and Europeans, gender and the production of knowledge are just a sample of the themes that are developed in this compilation.
    [Show full text]
  • Two Iron Technology Diffusion Routes in Eastern Europe
    328 Archeologické rozhledy LXX–2018 328–334 Two iron technology diffusion routes in Eastern Europe Dvě trasy šíření znalosti zpracování železa ve východní Evropě Vladimir I. Zavyalov – Nataliya N. Terekhova Archaeometallographic data suggest that there were two technological models in Eastern Europe as early as the Bronze Age–Early Iron Age transition period (9th–7th centuries BC). We link their development to two routes via which knowledge of use of ferrous metals diffused from Anatolia. The first route reached the North Caucasus, the second route passed through Greece and the Balkans to Central and Eastern Europe. archaeometallography – Eastern Europe – ferrous metals – transition period Archeometalografická data naznačují, že již v přechodu mezi dobou bronzovou a ranou dobou železnou (9.–7. stol. př. n. l.) existovaly ve východní Evropě dva technologické modely zpracování železa. Jejich rozvoj spojujeme se dvěma trasami, kterými se znalosti užívání železných kovů z Anatolie rozšířily. První trasa překročila Zakavkazsko, druhá trasa vedla přes Řecko a Balkán do střední a východní Evropy. archeometallografie – východní Evropa – železné kovy – přechodné období The issue of emergence and spread of ferrous metallurgy is still relevant despite the fact that it has been on the research agenda for quite a long time. L. Morgan (1935, 28) argued that ‘The production of iron was the event of events in human experience, without a par- allel, and without an equal, besides which all other inventions and discoveries were in- considerable, or at least subordinate’. Most researchers tend to believe that telluric iron production originated in Anatolia. The region had all basic preconditions, such as focused and systematic search of ore min- erals; understanding properties of minerals which could be turned to metal; pyrotechno- logical structures; use of artificial blowing to achieve high temperatures (when smelting); charring of wood (Waldbaum 1978, 23).
    [Show full text]
  • Elucidating Pathfinding Elements from the Kubi Gold Mine in Ghana
    minerals Article Elucidating Pathfinding Elements from the Kubi Gold Mine in Ghana Gabriel K. Nzulu 1,2,* , Babak Bakhit 1 , Hans Högberg 1 , Lars Hultman 1 and Martin Magnuson 1 1 Department of Physics, Chemistry and Biology (IFM), Linköping University, SE-58183 Linköping, Sweden; [email protected] (B.B.); [email protected] (H.H.); [email protected] (L.H.); [email protected] (M.M.) 2 Gold Corporation, No. 1, Yapei Link, Airport Residential Area, P.O. Box 9311, Accra 00233, Ghana * Correspondence: [email protected] Abstract: X-ray photoelectron spectroscopy (XPS) and energy dispersive X-ray spectroscopy (EDX) are applied to investigate the properties of fine-grained concentrates on artisanal, small-scale gold mining samples from the Kubi Gold Project of the Asante Gold Corporation near Dunwka-on-Offin in the Central Region of Ghana. Both techniques show that the Au-containing residual sediments are dominated by the host elements Fe, Ag, Al, N, O, Si, Hg, and Ti that either form alloys with gold or with inherent elements in the sediments. For comparison, a bulk nugget sample mainly consisting of Au forms an electrum, i.e., a solid solution with Ag. Untreated (impure) sediments, fine-grained Au concentrate, coarse-grained Au concentrate, and processed ore (Au bulk/nugget) samples were found to contain clusters of O, C, N, and Ag, with Au concentrations significantly lower than that of the related elements. This finding can be attributed to primary geochemical dispersion, which evolved from the crystallization of magma and hydrothermal liquids as well as the migration of metasomatic elements and the rapid rate of chemical weathering of lateralization in Citation: Nzulu, G.K.; Bakhit, B.; Högberg, H.; Hultman, L.; Magnuson, secondary processes.
    [Show full text]
  • CM17 469.Pdf
    Canadian Mineralogist VoL 17, pp.469-482 (1979) THEROLE OF GOLLECTORSIN THE FORMATIONOF THE PLATINUMDEPOSITS IN THEBUSHVELD COMPLEX S.A. HIEMSTRA Natianal Institute tor Metallurgy, Prtvate Bag X3015, Ratrdburg 2125, Soutlt Alrica ABsrRAcr INTRoDUcTIoN We consider the formation of the platinum de- Most of the sulfide occu,rrences of the posits in the Merensky and UG-2 Reefs in connec- Bushveld complex are associated with enriclr- tion with the action of collectors settling under ments in platinum-group metals. However, there the influence of gravity. The sulfides in the UG-2 the Reef, too small to have settled on their own, were are only three known occurrences where carried down by larger chromite grains in pieey- concentrations of these elements reach value$ back fashion. The sulfide droplets adhered to the of economic significance. These are the Merens- chromite grains either because they could wet the ky Reef (under which, for present puryroses chromite more readily than the silica.tes, or nu- is included the Plat Reef), the Upper Chromitite cleation of sulfide liquid droplets could have taken Layer (or UG-2 Reef), and the three dunite place preferentialli otr the surfaces of chromite pipes Driekop, Onverwacht and Mooihoek in grains. An iron alloy, stable only under exceptionally the eastern Bushveld. In this paper, attention Iow oxygen fugacity, could have acted as an effi- is given to one aspect of platinum deposits: the cient collector of platinum-group metals, which processes gave to the con- could have caused exceptional enrichment of some collection that rise magma fractions. Some of the mineral intergrowths centration of the platinum-group metals.
    [Show full text]
  • Archaeology of the Polar Eskimo
    ANTHROPOLOGICAL1 PAPERS OF TaHE AMERICAN MUSEUM OF NATURAL 'HISTrORY VOL. XXII, PART III ARCHAEOLOGY OF THE POLAR ESKIMO BY CLARK WISSLER NEW YORK PUBLISHED BY ORDER OF THE TRUSTEES 1918 ARCHAEOLOGY OF THE POLAR ESKIMO. BY CLARK WISSLER. 105 PREFACE. The objects upon which this study is based are from the archaeological collections made by members of the Crocker Land Expedition of the Ameri- can Museum of Natural History, 1913-1918. The sites represented are in the main on the shores of Northeast Greenland, which in historic times were occupied by a group of Eskimo known in America as Smith Sound Eskimo and in Denmark as the Polar Eskimo. The writer was not a mem- ber of the expedition, but represents the anthropological staff of this Mu- seum, in whose custody the collections were placed. He is not, therefore, familiar with the characteristics of the sites from which these objects come and can treat them only as objective examples of Eskimo culture. As such, they offer some suggestive contributions to Eskimo anthropology. The members of the expedition, particularly Doctor Edmund Otis Hovey, geologist of the Museum, Mr. Donald B. MacMillan, the leader of the Expedition, and Captain George Comer, well known to students of the Eskimo for his former contributions, all gave the greatest assistance in the preparation of these pages. The pen drawings were made by William Baake and the plans and map by S. Ichikawa. CLARK WISSLER. June, 1918. 107 CONTENTS. PAGE. PREFACE 107 INTRODUCTION *. ~111 CHARACTERISTICS OF THE LOCALITY 113 EXCAVATIONS IN COMER'S MIDDEN 114 THE AGE OF THE DEPOSIT 114 METHODS OF WORKING BONE AND IVORY 117 KNIVES 120 ULU OR WOMAN'S KNIFE 132 WHETSTONES 137 SPOKE SHAVES 137 SNOW KNIVES 137 THE ADZE 140 ICE PICKS 142 HAMMERS ' .
    [Show full text]
  • Pyrites, Meteorites and Meteor-Wrongs from Ancient Iran
    0320-07_Iran_Antiq_43_06_Overlaet 09-01-2008 14:37 Pagina 153 Iranica Antiqua, vol. XLIII, 2008 doi: 10.2143/IA.43.0.2024046 GREAT BALLS OF FIRE? PYRITES, METEORITES AND METEOR-WRONGS FROM ANCIENT IRAN BY Bruno OVERLAET (Royal Museums of Art and History, Brussels / Ghent University, Ghent) Abstract: Metallic nodules found in the Siyalk II settlement and in Iron Age III tombs in Luristan, Iran, were identified by the excavators as meteorites. However, these identifications must be questioned. The Siyalk nodules could be of telluric origin. The four Luristan specimens are identified as pyrite nodules. It is suggested that such nodules were used for fire-making, although other functions such as a use as sling balls are not to be excluded either. Keywords: pyrite, meteorite, fire-making, Luristan, Tepe Siyalk, Chamahzi Mumah, Gul Khanan Murdah, Iran. Meteors and meteor showers or shooting stars, like comets and other celes- tial anomalies, were in antiquity widely associated with acts of gods and were often seen as omens or divine warnings. When their fall had been wit- nessed and their remains could be retrieved, they could be venerated and placed in temples. A well known example is the stone (in antiquity consid- ered to be a meteorite) of Emesa (Cumont 1905: 2219-2222; Turcan 1985; Gradel 2004: 351-352). It was associated with the sun god and worshipped in its temple in Emesa, Syria. It was taken from its sanctuary to Rome by its high priest Marcus Aurelius Antoninus who adopted the sun god’s name Elagabalus on becoming emperor in 218 A.D.
    [Show full text]
  • May, the Stannern Achondrite Fell from the Sky, Landing in What Is Now the Czech Republic
    Meteorite Times Magazine Contents Paul Harris Featured Articles Accretion Desk by Martin Horejsi Jim’s Fragments by Jim Tobin Bob’s Findings by Robert Verish Micro Visions by John Kashuba Mitch’s Universe by Mitch Noda Terms Of Use Materials contained in and linked to from this website do not necessarily reflect the views or opinions of The Meteorite Exchange, Inc., nor those of any person connected therewith. In no event shall The Meteorite Exchange, Inc. be responsible for, nor liable for, exposure to any such material in any form by any person or persons, whether written, graphic, audio or otherwise, presented on this or by any other website, web page or other cyber location linked to from this website. The Meteorite Exchange, Inc. does not endorse, edit nor hold any copyright interest in any material found on any website, web page or other cyber location linked to from this website. The Meteorite Exchange, Inc. shall not be held liable for any misinformation by any author, dealer and or seller. In no event will The Meteorite Exchange, Inc. be liable for any damages, including any loss of profits, lost savings, or any other commercial damage, including but not limited to special, consequential, or other damages arising out of this service. © Copyright 2002–2021 The Meteorite Exchange, Inc. All rights reserved. No reproduction of copyrighted material is allowed by any means without prior written permission of the copyright owner. Meteorite Times Magazine Sorry it took me 213 years to show you my Stannern Meteorite Individual Martin Horejsi Two hundred and thirteen years ago this May, the Stannern achondrite fell from the sky, landing in what is now the Czech Republic.
    [Show full text]