A Study of Electrometric Methods for Determining Selenium and Tellurium
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Photocatalytic Performance of Cuxo/Tio2 Deposited by Hipims on Polyester Under Visible Light Leds: Oxidants, Ions Effect, and Reactive Oxygen Species Investigation
materials Article Photocatalytic Performance of CuxO/TiO2 Deposited by HiPIMS on Polyester under Visible Light LEDs: Oxidants, Ions Effect, and Reactive Oxygen Species Investigation Hichem Zeghioud 1 , Aymen Amine Assadi 2,*, Nabila Khellaf 3, Hayet Djelal 4, Abdeltif Amrane 2 and Sami Rtimi 5,* 1 Department of Process Engineering, Faculty of Engineering, Badji Mokhtar University, P.O. Box 12, 23000 Annaba, Algeria; [email protected] 2 Ecole Nationale Supérieure de Chimie de Rennes, Université de Rennes 1, CNRS, UMR 6226, Allée de Beaulieu, CS 50837, 35708 Rennes CEDEX 7, France; [email protected] 3 Laboratory of Organic Synthesis-Modeling and Optimization of Chemical Processes, Badji Mokhtar University, P.O. Box 12, 23000 Annaba, Algeria; [email protected] 4 Ecole des Métiers de l’Environnement, Campus de Ker Lann, 35170 Bruz, France; [email protected] 5 Ecole Polytechnique Fédérale de Lausanne, EPFL-STI-LTP, Station 12, CH-1015 Lausanne, Switzerland * Correspondence: [email protected] (A.A.A.); sami.rtimi@epfl.ch (S.R.) Received: 29 December 2018; Accepted: 22 January 2019; Published: 29 January 2019 Abstract: In the present study, we propose a new photocatalytic interface prepared by high-power impulse magnetron sputtering (HiPIMS), and investigated for the degradation of Reactive Green 12 (RG12) as target contaminant under visible light light-emitting diodes (LEDs) illumination. The CuxO/TiO2 nanoparticulate photocatalyst was sequentially sputtered on polyester (PES). The photocatalyst formulation was optimized by investigating the effect of different parameters such as the sputtering time of CuxO, the applied current, and the deposition mode (direct current magnetron sputtering, DCMS or HiPIMS). -
Working with Hazardous Chemicals
A Publication of Reliable Methods for the Preparation of Organic Compounds Working with Hazardous Chemicals The procedures in Organic Syntheses are intended for use only by persons with proper training in experimental organic chemistry. All hazardous materials should be handled using the standard procedures for work with chemicals described in references such as "Prudent Practices in the Laboratory" (The National Academies Press, Washington, D.C., 2011; the full text can be accessed free of charge at http://www.nap.edu/catalog.php?record_id=12654). All chemical waste should be disposed of in accordance with local regulations. For general guidelines for the management of chemical waste, see Chapter 8 of Prudent Practices. In some articles in Organic Syntheses, chemical-specific hazards are highlighted in red “Caution Notes” within a procedure. It is important to recognize that the absence of a caution note does not imply that no significant hazards are associated with the chemicals involved in that procedure. Prior to performing a reaction, a thorough risk assessment should be carried out that includes a review of the potential hazards associated with each chemical and experimental operation on the scale that is planned for the procedure. Guidelines for carrying out a risk assessment and for analyzing the hazards associated with chemicals can be found in Chapter 4 of Prudent Practices. The procedures described in Organic Syntheses are provided as published and are conducted at one's own risk. Organic Syntheses, Inc., its Editors, and its Board of Directors do not warrant or guarantee the safety of individuals using these procedures and hereby disclaim any liability for any injuries or damages claimed to have resulted from or related in any way to the procedures herein. -
1.1 10 Oxidation of Alcohols and Aldehydes
1.1 10 Oxidation of alcohols and aldehydes By the end of this spread, you should be able to … 1Describe the oxidation of primary alcohols to form aldehydes and carboxylic acids. 1Describe the oxidation of secondary alcohols to form ketones. 1Describe the oxidation of aldehydes to form carboxylic acids. Key definition Oxidation of alcohols You will recall from your AS chemistry studies that primary and secondary alcohols can A redox reaction is one in which both reduction and oxidation take place. be oxidised using an oxidising agent. s !SUITABLEOXIDISINGAGENTISASOLUTIONCONTAININGACIDIlEDDICHROMATEIONS + 2− H /Cr2O7 . s 4HEOXIDISINGMIXTURECANBEMADEFROMPOTASSIUMDICHROMATE +2Cr2O7, and sulfuric acid, H2SO. During the reaction, the acidified potassium dichromate changes from orange to green. Remember that tertiary alcohols are not oxidised by acidified dichromate ions. Primary alcohols Primary alcohols can be oxidised to aldehydes and to carboxylic acids (see AS Chemistry spread 2.2.3). H H H O H O Oxidation Oxidation H CCOH H CC H CC H H H H H OH Primary alcohol Aldehyde Carboxylic acid Figure 1 Ethanol oxidised to ethanal, and finally to ethanoic acid The equation for the oxidation of ethanol to the aldehyde ethanal is shown below. Note that the oxidising agent is shown as [O] – this simplifies the equation. CH3CH2OH + [O] }m CH3CHO + H2O When preparing aldehydes in the laboratory, you will need to distil the aldehyde from the reaction mixture as it is formed. This prevents the aldehyde from being oxidised further to a carboxylic acid. Key definition When making the carboxylic acid, the reaction mixture is usually heated under reflux before distilling the product off. -
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Preparation of Telluric Acid from Tellurium Dioxide by Oxidation with Potassium Permanganate Frank C. Mathers, Charles M. Rice, Howard Broderick, and Robert Forney, Indiana University General Statement Tellurium dioxide, Te0 2 , although periodically similar to sulfur dioxide, cannot be oxidized by nitric acid to the valence of six, i.e., to telluric acid, H 2 Te04.2H 2 0. Among the many stronger oxidizing agents that will produce this oxidation, potassium permanganate in a nitric acid solution is quite satisfactory. This paper gives directions and data for the preparation of telluric acid by this reaction. The making of telluric acid is a desirable laboratory experiment because (1) tellurim dioxide is available in large quantities and is easily obtained, (2) the telluric acid is a stable compound, easily purified, easily crystallized, and non-corrosive, and (3) students are interested in experimenting with the rarer elements. The small soluibility of telluric acid and the high solubility of both manganese and potassium nitrates in nitric acidi gives a sufficient differ- ence in properties for successful purification by crystallization of the telluric acid. Methods of Analyses Tellurium dioxide can be volumetrically 2 titrated in a sulfuric acid solution by an excess of standard potassium permanganate, followed by enough standard oxalic acid to decolorize the excess of permanganate. The excess of oxalic acid must then be titrated by more of the perman- ganate. The telluric acid can be titrated, like any ordinary monobasic acid, 3 (1911). with standard sodium hydroxide using phenolphthalein as an indicator, if an equal volume of glycerine is added. If any nitric acid is present, it must be neutralized first with sodium hydroxide, using methyl orange as indicator. -
Safety Data Sheet
SAFETY DATA SHEET Preparation Date: 06/23/2015 Revision Date: 10/27/2015 Revision Number: G2 1. IDENTIFICATION Product identifier Product code: P1282 Product Name: POTASSIUM DICHROMATE, CRYSTAL, REAGENT, ACS Other means of identification Synonyms: Bichromate of potash Chromium potassium oxide (K2Cr2O7) Dichromic acid dipotassium salt Dipotassium bichromate Dipotassium dichromate Dipotassium dichromium heptaoxide Iopezite Kaliumdichromat [German] Potassium bichromate Potassium chromate (K2Cr2O7) Potassium dichromate Potassium dichromate (K2(Cr2O7)) Potassium dichromate (K2Cr2O7) Potassium dichromate(VI) SRM 935a CAS #: 7778-50-9 RTECS # HX7680000 CI#: Not available Recommended use of the chemical and restrictions on use Recommended use: Analytical reagent. In tanning, printing, painting, electroplating and pyrotechnics. Uses advised against No information available Supplier: Spectrum Chemical Mfg. Corp 14422 South San Pedro St. Gardena, CA 90248 (310) 516-8000 Order Online At: https://www.spectrumchemical.com Emergency telephone number Chemtrec 1-800-424-9300 Contact Person: Martin LaBenz (West Coast) Contact Person: Ibad Tirmiz (East Coast) 2. HAZARDS IDENTIFICATION Classification This chemical is considered hazardous by the 2012 OSHA Hazard Communication Standard (29 CFR 1910.1200) Product code: P1282 Product name: POTASSIUM 1 / 16 DICHROMATE, CRYSTAL, REAGENT, ACS Acute toxicity - Oral Category 2 Acute toxicity - Dermal Category 1 Acute toxicity - Inhalation (Gases) Category 2 Acute toxicity - Inhalation (Dusts/Mists) Category 2 Skin -
Manufacturing of Potassium Permanganate Kmno4 This Is the Most Important and Well Known Salt of Permanganic Acid
Manufacturing of Potassium Permanganate KMnO4 This is the most important and well known salt of permanganic acid. It is prepared from the pyrolusite ore. It is prepared by fusing pyrolusite ore either with KOH or K2CO3 in presence of atmospheric oxygen or any other oxidising agent such as KNO3. The mass turns green with the formation of potassium manganate, K2MnO4. 2MnO2 + 4KOH + O2 →2K2MnO4 + 2H2O 2MnO2 + 2K2CO3 + O2 →2K2MnO4 + 2CO2 The fused mass is extracted with water. The solution is now treated with a current of chlorine or ozone or carbon dioxide to convert manganate into permanganate. 2K2MnO4 + Cl2 → 2KMnO4 + 2KCl 2K2MnO4 + H2O + O3 → 2KMnO4 + 2KOH + O2 3K2MnO4 + 2CO2 → 2KMnO4 + MnO2 + 2K2CO3 Now-a-days, the conversion is done electrolytically. It is electrolysed between iron cathode and nickel anode. Dilute alkali solution is taken in the cathodic compartment and potassium manganate solution is taken in the anodic compartment. Both the compartments are separated by a diaphragm. On passing current, the oxygen evolved at anode oxidises manganate into permanganate. At anode: 2K2MnO4 + H2O + O → 2KMnO4 + 2KOH 2- - - MnO4 → MnO4 + e + - At cathode: 2H + 2e → H2 Properties: It is purple coloured crystalline compound. It is fairly soluble in water. When heated alone or with an alkali, it decomposes evolving oxygen. 2KMnO4 → K2MnO4 + MnO2 + O2 4KMnO4 + 4KOH → 4K2MnO4 + 2H2O + O2 On treatment with conc. H2SO4, it forms manganese heptoxide via permanganyl sulphate which decomposes explosively on heating. 2KMnO4+3H2SO4 → 2KHSO4 + (MnO3)2SO4 + 2H2O (MnO3)2SO4 + H2O → Mn2O7 + H2SO4 Mn2O7 → 2MnO2 + 3/2O2 Potassium permanganate is a powerful oxidising agent. A mixture of sulphur, charcoal and KMnO4 forms an explosive powder. -
Chemical Compatibility Guide
Chemical Compatibility Guide Guide Applicable to the Following: PIG Portable Spill Containment Pool Guide Information This report is offered as a guide and was developed from information which, to the best of New Pig’s knowledge, was reliable and accurate. Due to variables and conditions of application beyond New Pig’s control, none of the data shown in this guide is to be construed as a guarantee, expressed or implied. New Pig assumes no responsibility, obligation, or liability in conjunction with the use or misuse of the information. PIG Spill Containment Pools are constructed from PVC-coated polyester fabric. The chemical resistance guide that follows shows the chemical resistance for the PVC layer only. This guide has been compiled to provide the user with general chemical resistance information. It does not reflect actual product testing. Ratings / Key or Ratings – Chemical Effect 1. Satisfactory to 72°F (22°C) 2. Satisfactory to 120°F (48°C) A = Excellent D = Severe Effect, not recommended for ANY use. B = Good — Minor Effect, slight corrosion or discoloration. N/A = Information not available. C = Fair — Moderate Effect, not recommended for continuous use. Softening, loss of strength, swelling may occur. Due to variables and conditions beyond our control, New Pig cannot guarantee that this product(s) will work to your satisfaction. To ensure effectiveness and your safety, we recommend that you conduct compatibility and absorption testing of your chemicals with this product prior to purchase. For additional questions or information, -
Perkin's Mauve: the History of the Chemistry
REFLECTIONS Perkin’s Mauve: The History of the Chemistry Andrew Filarowski Those of us who owe our living in part to the global dyestuff and chemical industry should pause today and remember the beginnings of this giant industry which started 150 years ago today with William Perkins’ discovery of mauveine whilst working in his home laboratory during the Easter holiday on April 28, 1856. Prior to this discovery, all textiles were dyed with natural dyestuffs and pigments. What did Perkin’s Reaction Entail? William Henry Perkin carried out his experiments at his home laboratory in the Easter break of 1856. He was trying to produce quinine (C20H24N2O2). This formula was known but not the structural formula. Because chemistry was in such an early stage of development Perkin thought that by simply balancing the masses (simple additive and subtractive chemistry) in an equation he would obtain the required compound. He therefore believed that if he took two allyltoluidine molecules, C10H13N, and oxidised them with three oxygen atoms (using potassium dichromate) he would get quinine (C20H24N2O2) and water. 2 (C10H13N) + 3O C20H24N2O2 + H2O It is unsurprising to us now but Perkin reported “that no quinine was formed, but only a dirty reddish brown precipitate.” However, he continued in his trials and decided to use aniline (C6H5NH2) and its sulphate, and to oxidise them using potassium dichromate. This produced a black precipitate that Perkin at first took to be a failed experiment, but he noticed on cleaning his equipment with alcohol that a coloured solution was obtained. Perkin’s Patent W H Perkin filed his patent on the 26th August 1856 for “Producing a new colouring matter for the dyeing with a lilac or purple color stuffs of silk, cotton, wool, or other materials.” (sic) Patent No. -
WO 2016/074683 Al 19 May 2016 (19.05.2016) W P O P C T
(12) INTERNATIONAL APPLICATION PUBLISHED UNDER THE PATENT COOPERATION TREATY (PCT) (19) World Intellectual Property Organization International Bureau (10) International Publication Number (43) International Publication Date WO 2016/074683 Al 19 May 2016 (19.05.2016) W P O P C T (51) International Patent Classification: (81) Designated States (unless otherwise indicated, for every C12N 15/10 (2006.01) kind of national protection available): AE, AG, AL, AM, AO, AT, AU, AZ, BA, BB, BG, BH, BN, BR, BW, BY, (21) International Application Number: BZ, CA, CH, CL, CN, CO, CR, CU, CZ, DE, DK, DM, PCT/DK20 15/050343 DO, DZ, EC, EE, EG, ES, FI, GB, GD, GE, GH, GM, GT, (22) International Filing Date: HN, HR, HU, ID, IL, IN, IR, IS, JP, KE, KG, KN, KP, KR, 11 November 2015 ( 11. 1 1.2015) KZ, LA, LC, LK, LR, LS, LU, LY, MA, MD, ME, MG, MK, MN, MW, MX, MY, MZ, NA, NG, NI, NO, NZ, OM, (25) Filing Language: English PA, PE, PG, PH, PL, PT, QA, RO, RS, RU, RW, SA, SC, (26) Publication Language: English SD, SE, SG, SK, SL, SM, ST, SV, SY, TH, TJ, TM, TN, TR, TT, TZ, UA, UG, US, UZ, VC, VN, ZA, ZM, ZW. (30) Priority Data: PA 2014 00655 11 November 2014 ( 11. 1 1.2014) DK (84) Designated States (unless otherwise indicated, for every 62/077,933 11 November 2014 ( 11. 11.2014) US kind of regional protection available): ARIPO (BW, GH, 62/202,3 18 7 August 2015 (07.08.2015) US GM, KE, LR, LS, MW, MZ, NA, RW, SD, SL, ST, SZ, TZ, UG, ZM, ZW), Eurasian (AM, AZ, BY, KG, KZ, RU, (71) Applicant: LUNDORF PEDERSEN MATERIALS APS TJ, TM), European (AL, AT, BE, BG, CH, CY, CZ, DE, [DK/DK]; Nordvej 16 B, Himmelev, DK-4000 Roskilde DK, EE, ES, FI, FR, GB, GR, HR, HU, IE, IS, IT, LT, LU, (DK). -
Mechanisms of Anaerobic Nitric Oxide Detoxification by Salmonella Enterica Serovar Typhimurium
Mechanisms of anaerobic nitric oxide detoxification by Salmonella enterica serovar Typhimurium Anke Arkenberg Thesis for the degree of Doctor of Philosophy School of Biological Sciences, University of East Anglia September 2013 © This copy of the thesis has been supplied on condition that anyone who consults it is understood to recognise that its copyright rests with the author and that no quotation from the thesis, nor any information derived therefrom, may be published without the author’s prior, written consent. Acknowledgements Firstly, I would like to thank my supervisory team of Gary Rowley, David Richardson and Margaret Wexler. Their guidance and support has allowed me to finish this thesis despite starting full-time work after the third year. Also, I am grateful to my parents as without their emotional and financial support this would not have been possible. Mama und Papa, ich danke Euch von ganzem Herzen, dass Ihr soviel Vertrauen in mich gesetzt, mich die ganze Zeit voll und ganz unterstützt habt und hoffe, dass es die Investition wert war. Huge thanks go to Luke, my financé, who has supported and motivated me throughout, but especially throughout the endeavour of working full-time and continuing the thesis work in the remaining time: You have carried me through the highs and lows and helped me to stay focused! Thanks also to my friends Connie, Eileen, Hannah, Hayley, Sarah: Meeting up at the office or elsewhere, eating some home-baked goodies, going for a run around the lake, and being able to forget the long lab hours has kept me positive and sane. -
Industrial Hydrocarbon Processes
Handbook of INDUSTRIAL HYDROCARBON PROCESSES JAMES G. SPEIGHT PhD, DSc AMSTERDAM • BOSTON • HEIDELBERG • LONDON NEW YORK • OXFORD • PARIS • SAN DIEGO SAN FRANCISCO • SINGAPORE • SYDNEY • TOKYO Gulf Professional Publishing is an imprint of Elsevier Gulf Professional Publishing is an imprint of Elsevier The Boulevard, Langford Lane, Kidlington, Oxford OX5 1GB, UK 30 Corporate Drive, Suite 400, Burlington, MA 01803, USA First edition 2011 Copyright Ó 2011 Elsevier Inc. All rights reserved No part of this publication may be reproduced, stored in a retrieval system or transmitted in any form or by any means electronic, mechanical, photocopying, recording or otherwise without the prior written permission of the publisher Permissions may be sought directly from Elsevier’s Science & Technology Rights Department in Oxford, UK: phone (+44) (0) 1865 843830; fax (+44) (0) 1865 853333; email: [email protected]. Alternatively you can submit your request online by visiting the Elsevier web site at http://elsevier.com/locate/ permissions, and selecting Obtaining permission to use Elsevier material Notice No responsibility is assumed by the publisher for any injury and/or damage to persons or property as a matter of products liability, negligence or otherwise, or from any use or operation of any methods, products, instructions or ideas contained in the material herein. Because of rapid advances in the medical sciences, in particular, independent verification of diagnoses and drug dosages should be made British Library Cataloguing in Publication Data -
125Te NMR Provides Evidence of Autoassociation of Organo-Ditellurides in Solution† Cite This: Phys
PCCP View Article Online PAPER View Journal | View Issue 125Te NMR provides evidence of autoassociation of organo-ditellurides in solution† Cite this: Phys. Chem. Chem. Phys., 2016, 18, 30740 P. J. W. Elder and I. Vargas-Baca* 125 The frequency of the resonance of Te of two organo-ditellurides, R–Te–Te–R (R = 4-CH3C6H4 and 2-(CH3)2NCH2C6H4), in solution undergoes a low-field shift as the concentration of the sample increases. In sharp contrast, the resonance of a sterically hindered ditelluride (R = (C6H5(CH3)2Si)3C) and telluric acid Received 25th August 2016, display the opposite effect. While the negative concentration coefficients can be explained by the change Accepted 11th October 2016 in magnetic susceptibility, the positive coefficients are consistent with autoassociation of the molecules DOI: 10.1039/c6cp05892b through tellurium-centred supramolecular interactions. Although the corresponding equilibrium constants are small, the process is shown to be exothermic. However, the influence of autoassociation is much www.rsc.org/pccp smaller than the effects of solvent polarity and the conformation of the ditelluride bond. Creative Commons Attribution-NonCommercial 3.0 Unported Licence. Introduction association constants for the adducts of benzotelluradiazoles with Lewis bases26 and monitor the association of anions with Supramolecular association is a recurrent feature in the structural tellurophenes.27 However, photolysis can be a concern with chemistry of organic derivatives of heavy p-block elements. The many systems. success of halogen bonding1–4 in areas as diverse as crystal Arguably the most practical spectroscopic method for the engineering,5–16 photonic materials17,18 organocatalysis19 and characterization of tellurium-centred supramolecular interactions biomimetic chemistry20 – to name a few – has stimulated the in solution is NMR.