Actual Symmetry of Symmetric Molecular Adducts in the Gas Phase, Solution and in the Solid State
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Reactivity and Functionalization of Naphthalene and Anthracene Complexes of {Tpw(NO)(Pme3)}
Reactivity and Functionalization of Naphthalene and Anthracene Complexes of {TpW(NO)(PMe3)} Laura Jessica Strausberg Baltimore, Maryland B.A., Hollins University, 2008 A Dissertation presented to the Graduate Faculty of the University of Virginia in Candidacy for the Degree of Doctor of Philosophy Department of Chemistry University of Virginia July, 2013 ii Abstract Chapter 1 introduces the organic chemistry of aromatic hydrocarbons, with attention paid to regiochemical outcomes of organic reactions. The binding of naphthalene and anthracene to metal complexes is discussed, along with organic transformations they undergo as a result of their complexation. The previous work on osmium and rhenium complexes of naphthalene from the Harman group is explored. Finally, some spectroscopic techniques for exploring the chemistry of {TpW(NO)(PMe3)} complexes of naphthalene and anthracene are introduced. Chapter 2 discusses the highly distorted allyl complexes formed from {TpW(NO)(PMe3)} and the exploration of their origin. Attempts at stereoselectively deprotonating these cationic complexes is also discussed. 2 Chapter 3 describes our study of TpW(NO)(PMe3)(3,4-η -naphthalene)’s ability to undergo a Diels-Alder reaction with N-methylmaleimide. A solvent study suggested that this reaction proceeds by a concerted mechanism. To probe the mechanism further, we synthesized a series of methylated and methoxylated naphthalene complexes and measured their rates of reaction with N-methylmaleimide compared to the parent complex. We found that 1- substitution on the naphthalene increased the rate of cycloaddition, even if the substituent was in the unbound ring, while 2-substitution slowed the reaction rate when in the bound ring. This information is consistent with a concerted mechanism, as a 2-substituted product would be less able to isomerize to form the active isomer for the cycloaddition to occur. -
Near Infrared Spectrophotometric Method for the Determination of Hydration Numbers
JOURNAL OF RESEARCH af the Natianal Bureau af Standards-A. Physics and Chemistry Val. 68A, No. 6, November- December 1964 Near Infrared Spectrophotometric Method for the Determination of Hydration Numbers Richard A. Durst* and John K. Taylor (July 29, 1964) The 980 mil absarptian band of water is cmplaycd in a new methad far the determinatian of hydratian numbers. '1'110 decrease in the concentration af "free" water is calculated fram thc change in absorbance resulting on the aclditian af an clectrolyte. Data arc given for ChrOl11l C chlonde and nltrate sa.lts in watcr-methanal salutians, ancl an cxtrapolatian is made to gIve the hydratIOn number In pure water. The results abtained by this technique agree WIth the values reparted uSing ather mcthads. 1. Introduction partially with the smrounding water structure. This sphere extends an indefinite distance from the Although aqueous electrolyte solutions have bee n ion until it ultimately blends into the bulk water studied in detail for many years, one of the most structme. Normally, the secondary hydration it; basic properties of such soiutions, the concept of very weak and values found experimentally vary ionic hydrati.on, is still poorly defined. Normally, widely depending on Lhe phenomenon 0 bserved. the effect of the coordinated water molecules is To date, the techniques employed for determining ignored when reactions in aqueous solutions are con hydration numbers have resulted in values which sidered. However, in many cases, this can lead to can be di \Tided into two groups: low values which serious errors in the interpretation of results. The seem to approximate the primary hydration numbers numerous experimental techniques which have been and considerably larger values corresponding to the employed to determine hydration numbers Q'ive some primary hydration plus all or part of the secondary indication of the widespread influence of io~- s olvent hydration sphere. -
Use of Solvents for Pahs Extraction and Enhancement of the Pahs Bioremediation in Coal- Tar-Contaminated Soils Pak-Hing Lee Iowa State University
Iowa State University Capstones, Theses and Retrospective Theses and Dissertations Dissertations 2000 Use of solvents for PAHs extraction and enhancement of the PAHs bioremediation in coal- tar-contaminated soils Pak-Hing Lee Iowa State University Follow this and additional works at: https://lib.dr.iastate.edu/rtd Part of the Environmental Engineering Commons Recommended Citation Lee, Pak-Hing, "Use of solvents for PAHs extraction and enhancement of the PAHs bioremediation in coal-tar-contaminated soils " (2000). Retrospective Theses and Dissertations. 13912. https://lib.dr.iastate.edu/rtd/13912 This Dissertation is brought to you for free and open access by the Iowa State University Capstones, Theses and Dissertations at Iowa State University Digital Repository. It has been accepted for inclusion in Retrospective Theses and Dissertations by an authorized administrator of Iowa State University Digital Repository. For more information, please contact [email protected]. INFORMATION TO USERS This manuscript has been reproduced from the microfilm master. UMI films the text directly from the original or copy submitted. Thus, some thesis and dissertation copies are in typewriter fece, while others may be from any type of computer printer. The quality of this reproduction is dependent upon the quaiity of the copy submitted. Broken or indistinct print colored or poor quality illustrations and photographs, print bleedthrough, substeindard margins, and improper alignment can adversely affect reproduction. In the unlilcely event that the author did not send UMI a complete manuscript and there are missing pages, these will be noted. Also, if unauthorized copyright material had to be removed, a note will indicate the deletion. -
Clathrate Desalination Method Applied to Produced Waters: Methodology & Results
Clathrate Desalination Method Applied to Produced Waters: Methodology & Results Patrick Baldoni-Andrey, Hervé Nabet, Matthieu Jacob, Pierre Pédenaud, Philippe Glénat Pascal Le Melinaire, Bruno Mottet producedwaterevents.com Presentation outline - Context and Stakes - Material and Methods - Results -Conclusion and Perspectives 2 Produced Water desalination – Sugar Land – 18jan2017 producedwaterevents.com The context –The E&P concerns Context and Stakes Water associated CAPEX & OPEX: regulatory constraints require efficient water treatments and the stakes are huge! Water production in the oil industry is 3 times the amount of produced oil! 80 3 Produced Water desalination – Sugar Land – 18jan2017 producedwaterevents.com Key Numbers for Total Context and Stakes Injection water Reinjection ≈ 55% mainly seawater If you cannot manage water, you cannot produce oil ! 4 Produced Water desalination – Sugar Land – 18jan2017 producedwaterevents.com Rationale for Produced water desalination Context and Stakes - Chemical Enhanced Oil Recovery - Fresh water Enhanced Oil Recovery - Recycling of produced water in the petroleum process (ex : Steam Assisted Gravity Drainage) - Minimize impact of water disposal in the environment onshore - Potential reuse, access to new resources - Low cost and innovative desalination (no evaporation, no pressure, …) - Value creation with low level calories 5 Produced Water desalination – Sugar Land – 18jan2017 producedwaterevents.com 6 Produced desalination Water – Sugar Land – 18jan2017 Cost of Treatment Reverse Osmosis -
Proton-Coupled Reduction of N2 Facilitated by Molecular Fe Complexes
Proton-Coupled Reduction of N2 Facilitated by Molecular Fe Complexes Thesis by Jonathan Rittle In Partial Fulfillment of the Requirements for the Degree of Doctor of Philosophy CALIFORNIA INSTITUTE OF TECHNOLOGY Pasadena, California 2016 (Defended November 9, 2015) ii 2016 Jonathan Rittle All Rights Reserved iii ACKNOWLEDGEMENTS My epochal experience in graduate school has been marked by hard work, intellectual growth, and no shortage of deadlines. These facts leave little opportunity for an acknowledgement of those whose efforts were indispensable to my progress and perseverance, and are therefore disclosed here. First and foremost, I would like to thank my advisor, Jonas Peters, for his tireless efforts in molding me into the scientist that I am today. His scientific rigor has constantly challenged me to strive for excellence and I am grateful for the knowledge and guidance he has provided. Jonas has given me the freedom to pursue scientific research of my choosing and shown a remarkable degree of patience while dealing with my belligerent tendencies. Perhaps equally important, Jonas has built a research group that is perpetually filled with the best students and postdoctoral scholars. Their contributions to my graduate experience are immeasurable and I wish them all the best of luck in their future activities. In particular, John Anderson, Dan Suess, and Ayumi Takaoka were senior graduate students who took me under their wings when I joined the lab as a naïve first-year graduate student. I am grateful for the time and effort that they collectively spent in teaching me the art of chemical synthesis and for our unforgettable experiences outside of lab. -
Step Formation Constants of Some Malonato Lanthanide Chelate Species Marvin Lee Adolphson Iowa State University
Iowa State University Capstones, Theses and Retrospective Theses and Dissertations Dissertations 1969 Step formation constants of some malonato lanthanide chelate species Marvin Lee Adolphson Iowa State University Follow this and additional works at: https://lib.dr.iastate.edu/rtd Part of the Physical Chemistry Commons Recommended Citation Adolphson, Marvin Lee, "Step formation constants of some malonato lanthanide chelate species " (1969). Retrospective Theses and Dissertations. 3809. https://lib.dr.iastate.edu/rtd/3809 This Dissertation is brought to you for free and open access by the Iowa State University Capstones, Theses and Dissertations at Iowa State University Digital Repository. It has been accepted for inclusion in Retrospective Theses and Dissertations by an authorized administrator of Iowa State University Digital Repository. For more information, please contact [email protected]. 70-13,563 ADOLPHSON, Marvin Lee, 1941- STEP FORMATION CONSTANTS OF SOME MÀLONATO LANTHANIDE CHELATE SPECIES. Iowa State University, Ph.D., 1969 Chemistiy, physical University Microfilms, Inc., Ann Arbor, Michigan THIS DISSERTATION HAS BEEN MICROFILMED EXACTLY AS RECEIVED STEP FORMATION CONSTANTS OF SOME MALONATO LANTHANIDE CHELATE SPECIES by Marvin Lee Adolphson A Dissertation Submitted to the Graduate Faculty in Partial Fulfillment of The Requirements for the Degree of DOCTOR OF PHILOSOPHY Major Subject: Physical Chemistry Approved; Signature was redacted for privacy. In/Charge of Major Work Signature was redacted for privacy. Signature was redacted for privacy. Iowa State University Ames, Iowa 1969 ii TABLE OF CONTENTS Page INTRODUCTION 1 COMPUTATIONS 4 EXPERIMENTAL DETAILS 15 EXPERIMENTAL RESULTS 35 DISCUSSION 56 SUMMARY 88 BIBLIOGRAPHY 89 ACKNOWLEDGMENT S 94 APPENDIX 95 1 INTRODUCTION The motivations for this research were fourfold. -
Symmetry of Three-Center, Four-Electron Bonds†‡
Chemical Science EDGE ARTICLE View Article Online View Journal | View Issue Symmetry of three-center, four-electron bonds†‡ b a c Cite this: Chem. Sci., 2020, 11,7979 Ann Christin Reiersølmoen, § Stefano Battaglia, § Sigurd Øien-Ødegaard, Arvind Kumar Gupta, d Anne Fiksdahl,b Roland Lindh a and Mate Erdelyi *a All publication charges for this article ´ ´ ´ have been paid for by the Royal Society of Chemistry Three-center, four-electron bonds provide unusually strong interactions; however, their nature remains ununderstood. Investigations of the strength, symmetry and the covalent versus electrostatic character of three-center hydrogen bonds have vastly contributed to the understanding of chemical bonding, whereas the assessments of the analogous three-center halogen, chalcogen, tetrel and metallic s^-type long bonding are still lagging behind. Herein, we disclose the X-ray crystallographic, NMR spectroscopic and computational investigation of three-center, four-electron [D–X–D]+ bonding for a variety of cations (X+ ¼ H+,Li+,Na+,F+,Cl+,Br+,I+,Ag+ and Au+) using a benchmark bidentate model system. Formation of a three-center bond, [D–X–D]+ is accompanied by an at least 30% shortening of the D–X Received 11th April 2020 bonds. We introduce a numerical index that correlates symmetry to the ionic size and the electron Accepted 19th June 2020 affinity of the central cation, X+. Providing an improved understanding of the fundamental factors DOI: 10.1039/d0sc02076a Creative Commons Attribution 3.0 Unported Licence. determining bond symmetry on a comprehensive level is expected to facilitate future developments and rsc.li/chemical-science applications of secondary bonding and hypervalent chemistry. -
Structural and Electronic Influences on Phosphite Basicity and Its Application to Heterogeneous and Homogeneous Catalysis David Evan Schiff Iowa State University
Iowa State University Capstones, Theses and Retrospective Theses and Dissertations Dissertations 1983 Structural and electronic influences on phosphite basicity and its application to heterogeneous and homogeneous catalysis David Evan Schiff Iowa State University Follow this and additional works at: https://lib.dr.iastate.edu/rtd Part of the Inorganic Chemistry Commons Recommended Citation Schiff, David Evan, "Structural and electronic influences on phosphite basicity and its application to heterogeneous and homogeneous catalysis " (1983). Retrospective Theses and Dissertations. 8960. https://lib.dr.iastate.edu/rtd/8960 This Dissertation is brought to you for free and open access by the Iowa State University Capstones, Theses and Dissertations at Iowa State University Digital Repository. It has been accepted for inclusion in Retrospective Theses and Dissertations by an authorized administrator of Iowa State University Digital Repository. For more information, please contact [email protected]. INFORMATION TO USERS This reproduction was made from a copy of a document sent to us for microfilming. While the most advanced technology has been used to photograph and reproduce this document, the quality of the reproduction is heavily dependent upon the quality of the material submitted. The following explanation of techniques is provided to help clarify markings or notations which may appear on this reproduction. 1.The sign or "target" for pages apparently lacking from the document photographed is "Missing Page(s)". If it was possible to obtain the missing page(s) or section, they are spliced into the film along with adjacent pages. This may have necessitated cutting through an image and duplicating adjacent pages to assure complete continuity. -
Characterization of the Solute Transport Properties of the Active Layers of Polyamide Thin Film Composite Membrnes
CHARACTERIZATION OF THE SOLUTE TRANSPORT PROPERTIES OF THE ACTIVE LAYERS OF POLYAMIDE THIN FILM COMPOSITE MEMBRNES Jingbo Wang A dissertation submitted to the faculty at the University of North Carolina at Chapel Hill in partial fulfillment of the requirements for the degree of Doctor of Philosophy in the Department of Environmental Sciences and Engineering in the Gillings School of Global Public Health. Chapel Hill 2018 Approved by: Orlando Coronell Michael Aitken David Couper Rene Lopez Jill Stewart © 2018 Jingbo Wang ALL RIGHTS RESERVED ii ABSTRACT Jingbo Wang: Characterization of the Solute Transport Properties of the Active Layers of Polyamide Thin Film Composite Membranes (Under the direction of Orlando Coronell) The overall objective of this study was to elucidate which parameter among solute partitioning, solute diffusion, and active layer thickness accounts for the differences in solute permeability among polyamide active layers of thin film composite (TFC) membranes. To accomplish the overall goal of this project, the following specific objectives were pursued: (i) to develop a method to measure solute partition coefficient (KS) from aqueous solution into polyamide active layer of TFC membranes; (ii) to quantify the solute partition (KS) and diffusion coefficient (DS) inside polyamide active layers of TFC membranes with a broad range of performance levels; (iii) to determining which parameter among solute partition coefficient (KS), solute diffusion coefficient (DS) and active layer thickness () accounts for the most difference -
Chapter 16 Liquid and Solids
Homework #2 Chapter 16 Liquid and Solids 7. Vapor Pressure: The pressure exerted by the vapor of a liquid when the vapor and the liquid are in dynamic equilibrium. The vapor pressure reflects the fact that within a system there is a distribution of energies that molecules can have, therefore, some molecules will have enough energy to overcome the intermolecular forces and enter into the gas phase. All liquids have some vapor pressure. The stronger the intermolecular forces the smaller the vapor pressure. All solids also have a vapor pressure. This is why if you leave ice in the freezer for a long time it “disappears.” The vapor pressure of solids is less than the vapor pressure of liquids. As the temperature increases the molecules have more energy, therefore, more molecules can escape into the gas phase (vapor pressure increases). When the vapor pressure is equal to the atmospheric pressure the solution boils. 9. a) Surface Tension As the intermolecular forces increase (↑), surface tension increases (↑). b) Viscosity As the intermolecular forces increase (↑), the viscosity increases (↑). c) Melting Point As the intermolecular forces increase (↑), the melting point increases (↑). d) Boiling Point As the intermolecular forces increase (↑), the boiling point increases (↑). e) Vapor Pressure As the intermolecular forces increase (↑), the vapor pressure decreases (↓). 11. Intermolecular Forces: The forces of attraction/repulsion between molecules. Intramolecular Forces: The forces of attraction/repulsion within a molecule. Intramolecular forces are stronger the intermolecular forces. Types of intermolecular forces: Dipole-Dipole Forces: The interaction between two electric dipoles in different molecules. Hydrogen Bonding: The attraction between a hydrogen atom (that is bonded to an O, N, or F atom) and an O, N, or F atom in a neighboring molecule. -
WHO Guidelines for Indoor Air Quality : Selected Pollutants
WHO GUIDELINES FOR INDOOR AIR QUALITY WHO GUIDELINES FOR INDOOR AIR QUALITY: WHO GUIDELINES FOR INDOOR AIR QUALITY: This book presents WHO guidelines for the protection of pub- lic health from risks due to a number of chemicals commonly present in indoor air. The substances considered in this review, i.e. benzene, carbon monoxide, formaldehyde, naphthalene, nitrogen dioxide, polycyclic aromatic hydrocarbons (especially benzo[a]pyrene), radon, trichloroethylene and tetrachloroethyl- ene, have indoor sources, are known in respect of their hazard- ousness to health and are often found indoors in concentrations of health concern. The guidelines are targeted at public health professionals involved in preventing health risks of environmen- SELECTED CHEMICALS SELECTED tal exposures, as well as specialists and authorities involved in the design and use of buildings, indoor materials and products. POLLUTANTS They provide a scientific basis for legally enforceable standards. World Health Organization Regional Offi ce for Europe Scherfi gsvej 8, DK-2100 Copenhagen Ø, Denmark Tel.: +45 39 17 17 17. Fax: +45 39 17 18 18 E-mail: [email protected] Web site: www.euro.who.int WHO guidelines for indoor air quality: selected pollutants The WHO European Centre for Environment and Health, Bonn Office, WHO Regional Office for Europe coordinated the development of these WHO guidelines. Keywords AIR POLLUTION, INDOOR - prevention and control AIR POLLUTANTS - adverse effects ORGANIC CHEMICALS ENVIRONMENTAL EXPOSURE - adverse effects GUIDELINES ISBN 978 92 890 0213 4 Address requests for publications of the WHO Regional Office for Europe to: Publications WHO Regional Office for Europe Scherfigsvej 8 DK-2100 Copenhagen Ø, Denmark Alternatively, complete an online request form for documentation, health information, or for per- mission to quote or translate, on the Regional Office web site (http://www.euro.who.int/pubrequest). -
Pharmaceutical Aspects of Salt and Cocrystal Forms of Apis and Characterization Challenges
AperTO - Archivio Istituzionale Open Access dell'Università di Torino Pharmaceutical aspects of salt and cocrystal forms of APIs and characterization challenges This is the author's manuscript Original Citation: Availability: This version is available http://hdl.handle.net/2318/1657587 since 2018-03-05T14:37:18Z Published version: DOI:10.1016/j.addr.2017.07.001 Terms of use: Open Access Anyone can freely access the full text of works made available as "Open Access". Works made available under a Creative Commons license can be used according to the terms and conditions of said license. Use of all other works requires consent of the right holder (author or publisher) if not exempted from copyright protection by the applicable law. (Article begins on next page) 05 October 2021 Pharmaceutical aspects of salt and cocrystal forms of APIs and characterization challenges Paolo Cerreia Vioglio, Michele R. Chierotti, Roberto Gobetto* Department of Chemistry, University of Torino, Via P. Giuria 7, 10125 Torino (Italy) Contents 1. Introduction 2. Definitions and general properties 2.1 Salts 2.2 Ionic Cocrystals and Salt Cocrystals 3. Synthesis techniques 4. Characterization challenges and techniques 4.1 Single Crystal X-Ray diffraction 4.2 Vibrational spectroscopies: IR and Raman 4.3 Solid-state Nuclear Magnetic Resonance 4.3.1 1H chemical shift 4.3.2 13C chemical shift 4.3.3 1H and 13C chemical shift anisotropy 4.3.4 15N chemical shift 4.3.5 15N chemical shift anisotropy 4.4 Computational Density Functional Theory Studies 4.5 X-ray photoelectron spectroscopy (XPS) 5. Selected examples 5.1 Salts 5.2 Salt Cocrystals (SCCs) 5.3 Ionic Cocrystals (ICCs) 6.