DOCSLIB.ORG

Gallium Phosphide Light Sources and Photocells

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Gallium Phosphide Light Sources and Photocells 136 PHILIPS TECHNICAL REVIEW VOLUME 26 Gallium phosphide light sources and photocells H. G. Grimmeiss, W. Kischio and H. Scholz 621.383 :546.681 '183 Preparation and doping of GaP The methods of analysis used by us have failed to Amongst semiconductors with a relatively large detect the presence of carbon, which interferes with energy (band) gap, gallium phosphide has aroused luminescence in GaP, and this implies that the samples interest for various reasons. For one thing, by reason must have a e concentration of less than 5 X 10-4 %. of its 2.25 eV band gap, it is suitable for making P-N In the undoped state these crystals only exhibit very diodes which in some cases emit light in the visible weak luminescence. range of the spectrum. Our first task was to prepare gallium phosphide of high purity since, as will be made clear below, the efficiency of GaP light sources is very much dependent on the purity of the starting material. GaP is prepared by allowing gallium to react with phosphine; an ample supply of the latter gas, in a very high state of purity, can be obtained by decomposition of aluminium phos- phide with water. The aluminium phosphide is pre- pared by reacting aluminium with phosphorus. A mixture of pure aluminium and red phosphorus in an atomic ratio of 1: 1.1 is placed in an iron crucible and ignited. The reaction is fairly violent: some of the phosphorus evaporates and escapes into the atmo- sphere, where it burns spontaneously (fig. J). The aluminium phosphide yielded by the reaction is a porous sintered substance, yellow in colour. The GaP is synthesized in the apparatus sketched in fig· 2. The round-bottomed flask is charged with alu- minium phosphide under a nitrogen atmosphere. The moist gas that evolves when the compound is decom- posed by water is first passed through a cooling jacket. This condenses most of its water vapour. Thereafter the gas passes through two traps cooled down to -78 DC by a mixture of acetone and dry ice. Finally it enters the furnace containing a charge of gallium. The metal has first been heated up to 800 DC in a stream of hydrogen; once this temperature is attained the hydrogen flow is cut off and the phosphine fed in. Tbe temperature is then raised to 1200 DC and held there for two hours. Fig. I. Reaction between powdered aluminium and red phos- This reaction converts one-fifth of the gallium into phorus, resulting in the formation of aluminium phosphide. GaP, yielding orange-tinted flakes having dimensions of roughly 4 X 4 X 0.2 mm. Most of the flakes are single To produce GaP that will luminesce satisfactorily crystals, the large faces being { I IJ} planes. However, the crystals must be doped, and both zinc and zinc crystals twinned on a { Ill} plane are not uncommon. plus oxygen have shown themselves effective doping The overall impurity concentration is less than 10-3 %. agents. Zinc gives rise to the emission of green light, zinc plus oxygen to the emission of red light with a peak at 700 nm. As will later appear, it is the red- Dr. H. G. Grimmeiss, Dr. W. Kischio and Dr. H. Sc/wlz are research workers at the Aachen laborat ory of' Philips Zen/ra/- luminescing crystals that are mainly of interest. The laboratorium GmbH. zinc and oxygen can be introduced in the form of ZnO 1965, No. 4/5/6 GaP LIGHT SOURCES AND PHOTOCELLS 137 or of Zn3(P04)2, but the use of one particular com- Optical and electrical properties of P-N junctions pound fixes the atomic ratio between the two elements. As already noted, GaP has the relatively large This can be varied at wiII if Ga203 or GaP04 is taken energy gap of 2.25 eV and because ofthis it is a highly as a source of oxygen and employed in conjunction interesting medium to investigate the electrical and opti- with metaIlic zinc or ZnO. cal properties of P-N junctions. It will also be recaIled Doping is carried out inthe foIlowing way. A quartz that particularly pure starting material is required container is filled with GaP, metaIlic gallium and the where luminescence is to be studied. Therefore we doping agents, heated up to 400°C in a vacuum and used GaP prepared in the manner described above for then sealed off. It is then heated up to 1230°C in a making experimental diodes. Î T T Fig. 2. Apparatus for preparing gallium phosphide. Aluminium phosphide in round-bottomed flask K breaks döwn under the action of water and gives off phosphoretted hydrogen which, after being dried and cleaned, is passed over gallium in a furnace o at 1200 "C, . furnace. The GaP forms a homogeneous solution Of the various methods for producing P-N junctions, with the gaIlium. Cooling must take place slowly if aIloying seemed the best suited to our purpose. But large, well-shaped crystals are to form out of the melt. one has to ensure that during the alloying process For that reason the container is lowered slowly through some gaIlium phosphide is taken up into the molten the floor of the vertical furnace chamber. The zinc aIloying metal, with the result that a greater or lesser segregation coefficient between the Ga melt and the amount of phosphorus is lost, depending on the reac- GaP is approximately unity. At the same time, recrys- tion time. This phosphorus ceases to be available for tallization is accompanied by a sharing of impurities recrystallization as GaP during the subsequent cooling between the solid and liquid phases. The process thus stages; the longer the alloying time, the thinner is the involves further purification of the GaP. recrystallization layer. Since the phosphorus escapes Doping with copper can be carried out by a partic- very quickly, we should have to use an aIloying method ularly efficient two-stage process. GaP and copper that would ensure rapid heating and cooling of the I are brought into contact at 400°C under an air pres- samples. We therefore decided to heat up the GaP sure of 0.5 torr, with the result that copper diffuses electrically, by passing a heavy current through an into the surface of the GaP crystals, which take on a iridium strip. In this way we could easily cut down black coloration: The tinted top layer is about 1 [.Lm the aIloying time to a second or so. In the method deep. It is essential that the GaP should be in intimate adopted by us, the ohmic contact is made of a gold- contact with the copper during this pretreatment. zinc alloy and the P-N junction is formed by alloying The blackened crystals are then annealed for 24 the GaP with tin. hours at 900 °C in an evacuated container. In the The P-N junctions thus produced run more or less course of the annealing the blackening disappears and paraIIel with the surface of the crystal. Fig. 3 shows the material recovers the appearance it had in the clearly that despite the short alloying time, only a undoped state. It is possible in this manner to convert very thin crystaIlization layer is formed. As me~sure- N-type GaP into P-type or, alternatively, by modifying ments of junction capacitance have established, the the pretreatment conditions, to retain the. original junctions obtained in this way are step junctions. Where N-type properties of the material. this is so, the inverse square of the junction capacitance 138 PHILlPS TECHNICAL REVIEW VOLUME 26 shows a linear relationship [1] to applied voltage; fig. 4 is a plot of this kind for P-N junctions made by us. The electrical properties of the diodes are governed above all by the relatively large energy gap of GaP [2]. Because it has a very low intrinsic conductivity, GaP can be used to make diodes which sometimes do not pass more than 10-11 A under a reverse bias of up to about 10 V; some have leakage currents of less than 10-13 A. For the same rea- sons the current in the for- ward direction shows a Fig. 3. Photograph of a P-N junction in a gallium phosphide diode fitted with a tin contact. logarithmic dependence on The P-type GaP is in the lower part of the print; part of the copper wire which carried the diode current can be seen at top right. applied voltage over sev- eralorders of magnitude (fig. 5). The result is that at 1.4 V, for example the rity levels one can arrange for this energy to be ra- ratio of forward to reverse current is about 1011 : 1. diated outwards, not as heat, but as light. The effect It is known that when a P-N junction is biased in is known as P-N or injection luminescence. the forward direction, minority charge-carriers are injected into both the P-region and N-region, where they are able to recombine with majority carriers al- ready present. In general, recombination may take v- 2 place by direct transitions from band to band or by / way of intermediate levels within the forbidden gap. In GaP however, for various reasons, of which the .. I compound's band structure is not the least important, 1/ recombination takes place mainly via impurity levels. 6 The energy released by recombination inside diodes is la normally transferred to the crystal lattice in the form of heat. However, by incorporation of suitable impu- 11 la 8 0 / »: / 2 } ./ V .../ V Ik • Jv / / V 20°C / 6 V 0,4 0,8 1,2 1,6 2 2,4V 1/ -Ud -2 o 2 4 6 8 la 12V -u o 2 4 6 12V Fig.
Load more

Recommended publications
  • TR-499: Indium Phosphide (CASRN 22398-80-7) in F344/N Rats And
    NTP TECHNICAL REPORT ON THE TOXICOLOGY AND CARCINOGENESIS STUDIES OF INDIUM PHOSPHIDE (CAS NO. 22398-80-7) IN F344/N RATS AND B6C3F1 MICE (INHALATION STUDIES) NATIONAL TOXICOLOGY PROGRAM P.O. Box 12233 Research Triangle Park, NC 27709 July 2001 NTP TR 499 NIH Publication No. 01-4433 U.S. DEPARTMENT OF HEALTH AND HUMAN SERVICES Public Health Service National Institutes of Health FOREWORD The National Toxicology Program (NTP) is made up of four charter agencies of the U.S. Department of Health and Human Services (DHHS): the National Cancer Institute (NCI), National Institutes of Health; the National Institute of Environmental Health Sciences (NIEHS), National Institutes of Health; the National Center for Toxicological Research (NCTR), Food and Drug Administration; and the National Institute for Occupational Safety and Health (NIOSH), Centers for Disease Control and Prevention. In July 1981, the Carcinogenesis Bioassay Testing Program, NCI, was transferred to the NIEHS. The NTP coordinates the relevant programs, staff, and resources from these Public Health Service agencies relating to basic and applied research and to biological assay development and validation. The NTP develops, evaluates, and disseminates scientific information about potentially toxic and hazardous chemicals. This knowledge is used for protecting the health of the American people and for the primary prevention of disease. The studies described in this Technical Report were performed under the direction of the NIEHS and were conducted in compliance with NTP laboratory health and safety requirements and must meet or exceed all applicable federal, state, and local health and safety regulations. Animal care and use were in accordance with the Public Health Service Policy on Humane Care and Use of Animals.
    [Show full text]
  • Transition Metal Phosphides for the Catalytic Hydrodeoxygenation of Waste Oils Into Green Diesel
    catalysts Review Transition Metal Phosphides for the Catalytic Hydrodeoxygenation of Waste Oils into Green Diesel M. Consuelo Alvarez-Galvan * , Jose M. Campos-Martin * and Jose L. G. Fierro * Energy and Sustainable Chemistry Group (EQS), Instituto de Catálisis y Petroleoquímica, CSIC, c/Marie Curie, 2 Cantoblanco, 28049 Madrid, Spain * Correspondence: [email protected] (M.C.A.-G.); [email protected] (J.M.C.-M.); jlgfi[email protected] (J.L.G.F.) Received: 28 February 2019; Accepted: 15 March 2019; Published: 22 March 2019 Abstract: Recently, catalysts based on transition metal phosphides (TMPs) have attracted increasing interest for their use in hydrodeoxygenation (HDO) processes destined to synthesize biofuels (green or renewable diesel) from waste vegetable oils and fats (known as hydrotreated vegetable oils (HVO)), or from bio-oils. This fossil-free diesel product is produced completely from renewable raw materials with exceptional quality. These efficient HDO catalysts present electronic properties similar to noble metals, are cost-efficient, and are more stable and resistant to the presence of water than other classical catalytic formulations used for hydrotreatment reactions based on transition metal sulfides, but they do not require the continuous supply of a sulfide source. TMPs develop a bifunctional character (metallic and acidic) and present tunable catalytic properties related to the metal type, phosphorous-metal ratio, support nature, texture properties, and so on. Here, the recent progress in TMP-based catalysts for HDO of waste oils is reviewed. First, the use of TMPs in catalysis is addressed; then, the general aspects of green diesel (from bio-oils or from waste vegetable oils and fats) production by HDO of nonedible oil compounds are presented; and, finally, we attempt to describe the main advances in the development of catalysts based on TMPs for HDO, with an emphasis on the influence of the nature of active phases and effects of phosphorous, promoters, and preparation methods on reactivity.
    [Show full text]
  • Binary and Ternary Transition-Metal Phosphides As Hydrodenitrogenation Catalysts
    Research Collection Doctoral Thesis Binary and ternary transition-metal phosphides as hydrodenitrogenation catalysts Author(s): Stinner, Christoph Publication Date: 2001 Permanent Link: https://doi.org/10.3929/ethz-a-004378279 Rights / License: In Copyright - Non-Commercial Use Permitted This page was generated automatically upon download from the ETH Zurich Research Collection. For more information please consult the Terms of use. ETH Library Diss. ETH No. 14422 Binary and Ternary Transition-Metal Phosphides as Hydrodenitrogenation Catalysts A dissertation submitted to the Swiss Federal Institute of Technology Zurich for the degree of Doctor of Natural Sciences Presented by Christoph Stinner Dipl.-Chem. University of Bonn born February 27, 1969 in Troisdorf (NRW), Germany Accepted on the recommendation of Prof. Dr. Roel Prins, examiner Prof. Dr. Reinhard Nesper, co-examiner Dr. Thomas Weber, co-examiner Zurich 2001 I Contents Zusammenfassung V Abstract IX 1 Introduction 1 1.1 Motivation 1 1.2 Phosphides 4 1.2.1 General 4 1.2.2 Classification 4 1.2.3 Preparation 5 1.2.4 Properties 12 1.2.5 Applications and Uses 13 1.3 Scope of the Thesis 14 1.4 References 16 2 Characterization Methods 1 2.1 FT Raman Spectroscopy 21 2.2 Thermogravimetric Analysis 24 2.3 Temperature-Programmed Reduction 25 2.4 X-Ray Powder Diffractometry 26 2.5 Nitrogen Adsorption 28 2.6 Solid State Nuclear Magnetic Resonance Spectroscopy 28 2.7 Catalytic Test 33 2.8 References 36 3 Formation, Structure, and HDN Activity of Unsupported Molybdenum Phosphide 37 3.1 Introduction
    [Show full text]
  • Chemical Vapor Deposition of Heteroepitaxial Boron Phosphide Thin Films
    University of Tennessee, Knoxville TRACE: Tennessee Research and Creative Exchange Doctoral Dissertations Graduate School 12-2013 Chemical Vapor Deposition of Heteroepitaxial Boron Phosphide Thin Films John Daniel Brasfield University of Tennessee - Knoxville, [email protected] Follow this and additional works at: https://trace.tennessee.edu/utk_graddiss Part of the Semiconductor and Optical Materials Commons Recommended Citation Brasfield, John Daniel, "Chemical aporV Deposition of Heteroepitaxial Boron Phosphide Thin Films. " PhD diss., University of Tennessee, 2013. https://trace.tennessee.edu/utk_graddiss/2558 This Dissertation is brought to you for free and open access by the Graduate School at TRACE: Tennessee Research and Creative Exchange. It has been accepted for inclusion in Doctoral Dissertations by an authorized administrator of TRACE: Tennessee Research and Creative Exchange. For more information, please contact [email protected]. To the Graduate Council: I am submitting herewith a dissertation written by John Daniel Brasfield entitled "Chemical Vapor Deposition of Heteroepitaxial Boron Phosphide Thin Films." I have examined the final electronic copy of this dissertation for form and content and recommend that it be accepted in partial fulfillment of the equirr ements for the degree of Doctor of Philosophy, with a major in Chemistry. Charles S. Feigerle, Major Professor We have read this dissertation and recommend its acceptance: Laurence Miller, Frank Vogt, Ziling Xue Accepted for the Council: Carolyn R. Hodges Vice Provost and Dean of the Graduate School (Original signatures are on file with official studentecor r ds.) Chemical Vapor Deposition of Heteroepitaxial Boron Phosphide Thin Films A Dissertation Presented for the Doctor of Philosophy Degree The University of Tennessee, Knoxville John Daniel Brasfield December 2013 Copyright © 2013 by John Daniel Brasfield All rights reserved.
    [Show full text]
  • Supporting Information For: Solution Phase Synthesis of Indium Gallium Phosphide Alloy Nanowires Nikolay Kornienko , Desiré D
    Supporting Information for: Solution Phase Synthesis of Indium Gallium Phosphide Alloy Nanowires Nikolay Kornienko1, Desiré D. Whitmore1, Yi Yu1, Stephen R. Leone1,2,4, Peidong Yang*1,3,5,6 1Department of Chemistry, 2Department of Physics and 3Department of Materials Science Engineering, University of California, Berkeley 94720, United States 4Chemical Sciences Division and 5Materials Sciences Division, Lawrence Berkeley National Lab, Berkeley CA 94720, United States 6Kavli Energy Nanosciences Institute, Berkeley, California 94720, United States * Correspondence to: [email protected] Table of Contents: Figure S1. TEM In/Ga growth seeds ............................................................................................................................. 2 Figure S2. TEM of InP and GaP NWs ............................................................................................................................. 2 Figure S3. Composition and diameter control ......................................................................................................... 3 Figure S4. XRD of InxGa1‐xP NWs .................................................................................................................................. 4 Figure S5. Electron diffraction of InxGa1‐xP NWs ................................................................................................... 5 Figure S6. Raman spectra of InP and GaP .................................................................................................................. 6
    [Show full text]
  • Arxiv:1010.1610V1 [Physics.Ins-Det] 8 Oct 2010 Ai Mouneyrac, David Emndtetm Osat O H Rpigadde- and Illumination
    Detrapping and retrapping of free carriers in nominally pure single crystal GaP, GaAs and 4H-SiC semiconductors under light illumination at cryogenic temperatures David Mouneyrac,1,2 John G. Hartnett,1 Jean-Michel Le Floch,1 Michael E. Tobar,1 Dominique Cros,2 Jerzy Krupka3∗ 1School of Physics, University of Western Australia 35 Stirling Hwy, Crawley 6009 WA Australia 2Xlim, UMR CNRS 6172, 123 av. Albert Thomas, 87060 Limoges Cedex - France 3Institute of Microelectronics and Optoelectronics Department of Electronics, Warsaw University of Technology, Warsaw, Poland (Dated: October 27, 2018) We report on extremely sensitive measurements of changes in the microwave properties of high purity non-intentionally-doped single-crystal semiconductor samples of gallium phosphide, gallium arsenide and 4H-silicon carbide when illuminated with light of different wavelengths at cryogenic temperatures. Whispering gallery modes were excited in the semiconductors whilst they were cooled on the coldfinger of a single-stage cryocooler and their frequencies and Q-factors measured under light and dark conditions. With these materials, the whispering gallery mode technique is able to resolve changes of a few parts per million in the permittivity and the microwave losses as compared with those measured in darkness. A phenomenological model is proposed to explain the observed changes, which result not from direct valence to conduction band transitions but from detrapping and retrapping of carriers from impurity/defect sites with ionization energies that lay in the semicon- ductor band gap. Detrapping and retrapping relaxation times have been evaluated from comparison with measured data. PACS numbers: 72.20.Jv 71.20.Nr 77.22.-d I.
    [Show full text]
  • Subject Index
    SUBJECT INDEX Vol. 1: 1–698, Vol. 2: 699–1395, Vol. 3: 1397–2111, Vol. 4: 2113–2798, Vol. 5: 2799–3440. Page numbers suffixed by t and f refer to Tables and Figures respectively. Absorption spectra in aqueous solution, 752–770 of americium, 1364–1368 compounds of, 721–752 americium (III), 1364–1365, 1365f coordination complexes in solution, americium (IV), 1365 771–782 americium (V), 1366, 1367f history of, 699–700 americium (VI), 1366, 1367f isotope production, 702–703 americium (VII), 1367–1368, 1368f metallic state of, 717–721 of liquid plutonium, 963 in nature, 703–704 of neptunium, 763–766, 763f, 786–787 nuclear properties of, 700–702 neptunium (VII) ternary oxides, 729 separation and purification, 704–717 of plutonium plutonium hexafluoride, 1088, 1089f atomic properties of, 857–862 ions, 1113–1117, 1116t compounds of, 987–1108 plutonium (IV), 849 metal and intermetallic compounds of, polymerization, 1151, 1151f 862–987 tetrachloride, 1093–1094, 1094f natural occurrence of, 822–824 tribromide, 1099t, 1100 nuclear properties of, 815–822 trichloride, 1099, 1099t separation and purification of, 826–857 Accelerator mass spectrometry (AMS), of solution chemistry of, 1108–1203 neptunium, 790 Actinide elements Acetates atomic volumes of, 922–923, 923f of americium, 1322, 1323t extraction of of plutonium, 1177, 1180 DIDPA, 1276 Acetone, derived compounds, of americium, HDEHP, 1275 1322, 1323t, 1324 organophosphorus and Acids carbamoylphosphonate reagents, for Purex process, 711 1276–1278 for solvent extraction, 839 stripping of, 1280–1281 Actinide
    [Show full text]
  • Basic Light Emitting Diodes
    The following is for information purposes only and comes with no warranty. See http://www.bristolwatch.com/ Light Emitting Diodes Light Emitting Diodes are made from compound type semiconductor materials such as Gallium Arsenide (GaAs), Gallium Phosphide (GaP), Gallium Arsenide Phosphide (GaAsP), Silicon Carbide (SiC) or Gallium Indium Nitride (GaInN). The exact choice of the semiconductor material used will determine the overall wavelength of the photon light emissions and therefore the resulting color of the light emitted, as in the case of the visible light colored LEDs, (RED, AMBER, GREEN etc). Before a light emitting diode can "emit" any form of light it needs a current to flow through it, as it is a current dependent device. As the LED is to be connected in a forward bias condition across a power supply it should be Current Limited using a series resistor to protect it from excessive current flow. From the table above we can see that each LED has its own forward voltage drop across the PN junction and this parameter which is determined by the semiconductor material used is the forward voltage drop for a given amount of forward conduction current, typically for a forward current of 20mA. In most cases LEDs are operated from a low voltage DC supply, with a series resistor to limit the forward current to a suitable value from say 5mA for a simple LED indicator to 30mA or more where a high brightness light output is needed. Typical LED Characteristics Semiconductor Material Wavelength Color voltage at 20mA GaAs 850-940nm Infra-Red 1.2v GaAsP 630-660nm Red 1.8v GaAsP 605-620nm Amber 2.0v GaAsP:N 585-595nm Yellow 2.2v GaP 550-570nm Green 3.5v SiC 430-505nm Blue 3.6v GaInN 450nm White 4.0v 1 Multi-LEDs LEDs are available in a wide range of shapes, colors and various sizes with different light output intensities available, with the most common (and cheapest to produce) being the standard 5mm Red LED.
    [Show full text]
  • Organometallic Pnictogen Chemistry
    Institut für Anorganische Chemie 2014 Fakultät für Chemie und Pharmazie | Sabine Reisinger aus Regensburg, geb. Scheuermayer am 15.07.1983 Studium: Chemie, Universität Regensburg Abschluss: Diplom Promotion: Prof. Dr. Manfred Scheer, Institut für Anorganische Chemie Sabine Reisinger Die vorliegende Arbeit enthält drei Kapitel zu unterschiedlichen Aspekten der metallorganischen Phosphor- und Arsen-Chemie. Zunächst werden Beiträge zur supramolekularen Chemie mit 5 Pn-Ligandkomplexen basierend auf [Cp*Fe(η -P5)] und 5 i [Cp*Fe(η - Pr3C3P2)] gezeigt, gefolgt von der Eisen-vermittelten Organometallic Pnictogen Aktivierung von P4, die zu einer selektiven C–P-Bindungsknüpfung führt, während das dritte Kapitel die Verwendung von Phosphor Chemistry – Three Aspects und Arsen als Donoratome in mehrkernigen Komplexen mit paramagnetischen Metallionen behandelt. Sabine Reisinger 2014 Alumniverein Chemie der Universität Regensburg E.V. [email protected] http://www.alumnichemie-uniregensburg.de Aspects Three – Chemistry Pnictogen Organometallic Fakultät für Chemie und Pharmazie ISBN 978-3-86845-118-4 Universität Regensburg Universitätsstraße 31 93053 Regensburg www.uni-regensburg.de 9 783868 451184 4 Sabine Reisinger Organometallic Pnictogen Chemistry – Three Aspects Organometallic Pnictogen Chemistry – Three Aspects Dissertation zur Erlangung des Doktorgrades der Naturwissenschaften (Dr. rer. nat.) der Fakultät für Chemie und Pharmazie der Universität Regensburg vorgelegt von Sabine Reisinger, geb. Scheuermayer Regensburg 2014 Die Arbeit wurde von Prof. Dr. Manfred Scheer angeleitet. Das Promotionsgesuch wurde am 20.06.2014 eingereicht. Das Kolloquium fand am 11.07.2014 statt. Prüfungsausschuss: Vorsitzender: Prof. Dr. Helmut Motschmann 1. Gutachter: Prof. Dr. Manfred Scheer 2. Gutachter: Prof. Dr. Henri Brunner weiterer Prüfer: Prof. Dr. Bernhard Dick Dissertationsreihe der Fakultät für Chemie und Pharmazie der Universität Regensburg, Band 4 Herausgegeben vom Alumniverein Chemie der Universität Regensburg e.V.
    [Show full text]
  • Nonlinear Properties of III-V Semiconductor Nanowaveguides
    Nonlinear Properties of III-V Semiconductor Nanowaveguides ELEONORA DE LUCA Doctoral Thesis in Physics School of Engineering Sciences KTH Royal Institute of Technology Stockholm, Sweden 2019 Akademisk avhandling som med tillstånd av Kungliga Tekniska högskolan fram- lägges till offentlig granskning för avläggande av teknologie doktorsexamen i fysik onsdag den 23 oktober 2019 klockan 10:00 i sal FA32, AlbaNova Universitetscent- rum, Kungliga Tekniska Högskolan, Roslagstullsbacken 21, Stockholm. TRITA-SCI-FOU 2019:45 • ISBN 978-91-7873-318-7 "O frati," dissi, "che per cento milia perigli siete giunti a l’occidente, a questa tanto picciola vigilia d’i nostri sensi ch’é del rimanente non vogliate negar l’esperïenza, di retro al sol, del mondo sanza gente. Considerate la vostra semenza: fatti non foste a viver come bruti, ma per seguir virtute e canoscenza". Dante Alighieri. Commedia. Inferno – Canto XXVI. "O brothers, who amid a hundred thousand Perils," I said, "have come unto the West, To this so inconsiderable vigil Which is remaining of your senses still, Be ye unwilling to deny the knowledge, Following the sun, of the unpeopled world. Consider ye the seed from which ye sprang; Ye were not made to live like unto brutes, But for pursuit of virtue and of knowledge" Dante Alighieri. Commedia. Inferno – Canto XXVI. Translated by Henry Wadsworth Longfellow. Abstract Nonlinear optics (NLO) plays a major role in the modern world: nonlin- ear optical phenomena have been observed in a wavelength range going from the deep infrared to the extreme ultraviolet, to THz radiation. The optical nonlinearities can be found in crystals, amorphous materials, polymers, liquid crystals, liquids, organic materials, and even gases and plasmas.
    [Show full text]
  • Chemical Names and CAS Numbers Final
    Chemical Abstract Chemical Formula Chemical Name Service (CAS) Number C3H8O 1‐propanol C4H7BrO2 2‐bromobutyric acid 80‐58‐0 GeH3COOH 2‐germaacetic acid C4H10 2‐methylpropane 75‐28‐5 C3H8O 2‐propanol 67‐63‐0 C6H10O3 4‐acetylbutyric acid 448671 C4H7BrO2 4‐bromobutyric acid 2623‐87‐2 CH3CHO acetaldehyde CH3CONH2 acetamide C8H9NO2 acetaminophen 103‐90‐2 − C2H3O2 acetate ion − CH3COO acetate ion C2H4O2 acetic acid 64‐19‐7 CH3COOH acetic acid (CH3)2CO acetone CH3COCl acetyl chloride C2H2 acetylene 74‐86‐2 HCCH acetylene C9H8O4 acetylsalicylic acid 50‐78‐2 H2C(CH)CN acrylonitrile C3H7NO2 Ala C3H7NO2 alanine 56‐41‐7 NaAlSi3O3 albite AlSb aluminium antimonide 25152‐52‐7 AlAs aluminium arsenide 22831‐42‐1 AlBO2 aluminium borate 61279‐70‐7 AlBO aluminium boron oxide 12041‐48‐4 AlBr3 aluminium bromide 7727‐15‐3 AlBr3•6H2O aluminium bromide hexahydrate 2149397 AlCl4Cs aluminium caesium tetrachloride 17992‐03‐9 AlCl3 aluminium chloride (anhydrous) 7446‐70‐0 AlCl3•6H2O aluminium chloride hexahydrate 7784‐13‐6 AlClO aluminium chloride oxide 13596‐11‐7 AlB2 aluminium diboride 12041‐50‐8 AlF2 aluminium difluoride 13569‐23‐8 AlF2O aluminium difluoride oxide 38344‐66‐0 AlB12 aluminium dodecaboride 12041‐54‐2 Al2F6 aluminium fluoride 17949‐86‐9 AlF3 aluminium fluoride 7784‐18‐1 Al(CHO2)3 aluminium formate 7360‐53‐4 1 of 75 Chemical Abstract Chemical Formula Chemical Name Service (CAS) Number Al(OH)3 aluminium hydroxide 21645‐51‐2 Al2I6 aluminium iodide 18898‐35‐6 AlI3 aluminium iodide 7784‐23‐8 AlBr aluminium monobromide 22359‐97‐3 AlCl aluminium monochloride
    [Show full text]
  • Agricultural Commodity Protection by Phosphine Fumigation: Programmatic Environmental Assessment Tools Annex
    AGRICULTURAL COMMODITY PROTECTION BY PHOSPHINE FUMIGATION PROGRAMMATIC ENVIRONMENTAL ASSESSMENT TOOLS ANNEX NOVEMBER 2013 This publication was produced for review by the United States Agency for International Development (USAID). It was prepared under USAID’s Global Environmental Management Support (GEMS) project. Cover photos: Phosphine fumigation monitoring equipment (top left), DIMEGSA Pest Control staff in Guatemala (top right), USAID food commodities stored in a warehouse (bottom). COMMODITY PROTECTION BY PHOSPHINE FUMIGATION IN USAID FOOD AID PROGRAMS PROGRAMMATIC ENVIRONMENTAL ASSESSMENT TOOLS ANNEX Updated December 2015 (original NOVEMBER 2013) Contract No.: AID-OAA-M-11-00021 Prepared for: Office of Food for Peace Bureau for Democracy, Conflict and Humanitarian Assistance United States Agency for International Development Prepared under: The Global Environmental Management Support Project (GEMS), Award Number AID-OAA-M-11-00021. The Cadmus Group, Inc., prime contractor (www.cadmusgroup.com). Sun Mountain International, principal partner (www.smtn.org). DISCLAIMER Until and unless this document is approved by USAID as a 22 CFR 216 Programmatic Environmental Assessment, the contents may not necessarily reflect the views of the United States Agency for International Development or the United States Government. TABLE OF CONTENTS ANNEX T-1: GUIDE: FUMIGATION COMPLIANCE GUIDANCE FOR USAID PARTNERS…..…….1 ANNEX T-2: TEMPLATE: FOOD COMMODITY PROTECTION PERSUAP FOR PHOSPHINE FUMIGATION & CONTACT PESTICIDES…………………………………………………..…………4 ANNEX
    [Show full text]