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Measuring and Predicting Sooting Tendencies of Oxygenates, Alkanes, Alkenes, Cycloalkanes, and Aromatics on a Unified Scale
Measuring and Predicting Sooting Tendencies of Oxygenates, Alkanes, Alkenes, Cycloalkanes, and Aromatics on a Unified Scale Dhrubajyoti D. Dasa,1, Peter St. Johnb,1, Charles S. McEnallya,∗, Seonah Kimb, Lisa D. Pfefferlea aYale University, Department of Chemical and Environmental Engineering, New Haven CT 06520 bNational Renewable Energy Laboratory, Golden CO 80401 Abstract Soot from internal combustion engines negatively affects health and climate. Soot emissions might be reduced through the expanded usage of appropriate biomass-derived fuels. Databases of sooting indices, based on measuring some aspect of sooting behavior in a standardized combustion environment, are useful in providing information on the comparative sooting tendencies of different fuels or pure compounds. However, newer biofuels have varied chemical structures including both aromatic and oxygenated functional groups, making an accurate measurement or prediction of their sooting tendency difficult. In this work, we propose a unified sooting tendency database for pure compounds, including both regular and oxygenated hydrocarbons, which is based on combining two disparate databases of yield-based sooting tendency measurements in the literature. Unification of the different databases was made possible by leveraging the greater dynamic range of the color ratio pyrometry soot diagnostic. This unified database contains a substantial number of pure compounds (≥ 400 total) from multiple categories of hydrocarbons important in modern fuels and establishes the sooting tendencies of aromatic and oxygenated hydrocarbons on the same numeric scale for the first time. Using this unified sooting tendency database, we have developed a predictive model for sooting behavior applicable to a broad range of hydrocarbons and oxygenated hydrocarbons. The model decomposes each compound into single-carbon fragments and assigns a sooting tendency contribution to each fragment based on regression against the unified database. -
Transport of Dangerous Goods
ST/SG/AC.10/1/Rev.16 (Vol.I) Recommendations on the TRANSPORT OF DANGEROUS GOODS Model Regulations Volume I Sixteenth revised edition UNITED NATIONS New York and Geneva, 2009 NOTE The designations employed and the presentation of the material in this publication do not imply the expression of any opinion whatsoever on the part of the Secretariat of the United Nations concerning the legal status of any country, territory, city or area, or of its authorities, or concerning the delimitation of its frontiers or boundaries. ST/SG/AC.10/1/Rev.16 (Vol.I) Copyright © United Nations, 2009 All rights reserved. No part of this publication may, for sales purposes, be reproduced, stored in a retrieval system or transmitted in any form or by any means, electronic, electrostatic, magnetic tape, mechanical, photocopying or otherwise, without prior permission in writing from the United Nations. UNITED NATIONS Sales No. E.09.VIII.2 ISBN 978-92-1-139136-7 (complete set of two volumes) ISSN 1014-5753 Volumes I and II not to be sold separately FOREWORD The Recommendations on the Transport of Dangerous Goods are addressed to governments and to the international organizations concerned with safety in the transport of dangerous goods. The first version, prepared by the United Nations Economic and Social Council's Committee of Experts on the Transport of Dangerous Goods, was published in 1956 (ST/ECA/43-E/CN.2/170). In response to developments in technology and the changing needs of users, they have been regularly amended and updated at succeeding sessions of the Committee of Experts pursuant to Resolution 645 G (XXIII) of 26 April 1957 of the Economic and Social Council and subsequent resolutions. -
An Analysis of Electrophilic Aromatic Substitution: a “Complex Approach” PCCP
Volume 23 Number 9 7 March 2021 Pages 5033–5682 PCCP Physical Chemistry Chemical Physics rsc.li/pccp ISSN 1463-9076 PERSPECTIVE Janez Cerkovnik et al . An analysis of electrophilic aromatic substitution: a “complex approach” PCCP View Article Online PERSPECTIVE View Journal | View Issue An analysis of electrophilic aromatic substitution: a ‘‘complex approach’’† Cite this: Phys. Chem. Chem. Phys., a a b 2021, 23, 5051 Nikola Stamenkovic´, Natasˇa Poklar Ulrih and Janez Cerkovnik * Electrophilic aromatic substitution (EAS) is one of the most widely researched transforms in synthetic organic chemistry. Numerous studies have been carried out to provide an understanding of the nature of its reactivity pattern. There is now a need for a concise and general, but detailed and up-to-date, overview. The basic principles behind EAS are essential to our understanding of what the mechanisms underlying EAS are. To date, textbook overviews of EAS have provided little information about the Received 5th October 2020, mechanistic pathways and chemical species involved. In this review, the aim is to gather and present the Accepted 21st December 2020 up-to-date information relating to reactivity in EAS, with the implication that some of the key concepts DOI: 10.1039/d0cp05245k will be discussed in a scientifically concise manner. In addition, the information presented herein suggests certain new possibilities to advance EAS theory, with particular emphasis on the role of modern Creative Commons Attribution-NonCommercial 3.0 Unported Licence. rsc.li/pccp -
Secondary Organic Aerosol Formation from the Ozonolysis of Cycloalkenes and Related Compounds*
252 Chapter 7 Secondary Organic Aerosol Formation from the Ozonolysis of Cycloalkenes and Related Compounds* * This chapter is reproduced by permission from “Secondary organic aerosol formation from ozonolysis of cycloalkenes and related compounds” by M.D. Keywood, V. Varutbangkul, R. Bahreini, R.C. Flagan, J.H. Seinfeld, Environmental Science and Technology, 38 (15): 4157-4164, 2004. Copyright 2004, American Chemical Society. 253 7.1. Abstract The secondary organic aerosol (SOA) yields from the laboratory chamber ozonolysis of a series of cycloalkenes and related compounds are reported. The aim of this work is to investigate the effect of the structure of the hydrocarbon parent molecule on SOA formation for a homologous set of compounds. Aspects of the compound structures that are varied include the number of carbon atoms present in the cycloalkene ring (C5 to C8), the presence and location of methyl groups, and the presence of an exocyclic or endocyclic double bond. The specific compounds considered here are cyclopentene, cyclohexene, cycloheptene, cyclooctene, 1-methyl-1-cyclopentene, 1-methyl-1- cyclohexene, 1-methyl-1-cycloheptene, 3-methyl-1-cyclohexene, and methylene cyclohexane. SOA yield is found to be a function of the number of carbons present in the cycloalkene ring, with increasing number resulting in increased yield. Yield is enhanced by the presence of a methyl group located at a double-bonded site but reduced by the presence of a methyl group at a non-double bonded site. The presence of an exocyclic double bond also leads to a reduced yield relative to the equivalent methylated cycloalkene. On the basis of these observations, the SOA yield for terpinolene relative to the other cyclic alkenes is qualitatively predicted, and this prediction compares well to measurements of SOA yield from the ozonolysis of terpinolene. -
Epoxidation of Cyclopentene, Cyclohexene and Cycloheptene by Acetylperoxyl Radicals
Epoxidation of Cyclopentene, Cyclohexene and Cycloheptene by Acetylperoxyl Radicals J. R. Lindsay Smith, D. M. S. Smith, M. S. Stark* and D. J. Waddington Department of Chemistry, University of York, York, YO10 5DD, United Kingdom To further the current understanding of how peroxyl radicals add to C=C double bonds,eg. 1-3 a series of cyclic alkenes (cyclopentene, cyclohexene and cycloheptene) were reacted with acetylperoxyl radicals over the temperature range 373 - 433 K, via the co- oxidation of acetaldehyde, the cyclic alkene and a reference alkene. The resulting epoxides were monitored by GC-FID, allowing the determination of the Arrhenius parameters given in Table 1 for these addition reactions. 3 -1 -1 -1 Alkene log10(A / dm mol s ) Eact / kJ mol cyclopentene 9.7±0.6 31.2±5.0 cyclohexene 7.7±0.7 17.4±5.3 cycloheptene 8.8±0.8 25.5±6.5 cis-2-butene4 8.1±0.5 22.9±3.8 Table 1: Arrhenius parameters for the addition of acetylperoxyl radicals to cyclic alkenes and cis-2-butene. Parameters for cis-2-butene are also given for comparison,4 as it would be expected that a relatively unstrained cycloalkene would behave in a similar manner to this non-cyclic alkene; this is indeed found to be so, with no statistically significant difference between cyclohexene and cis-2-butene. Indeed the measured activation energy for cyclohexene fits in well with correlation between charge transfer ( Ec) and activation energy that is known to exist for the addition of acetylperoxyl to acyclic mono-alkenes.1 Cyclopentene however does have a significantly larger pre-exponential factor and activation energy than either cyclohexene or cis-2-butene. -
Transition Metal Complexes of Dicyanoacetylene
Louisiana State University LSU Digital Commons LSU Historical Dissertations and Theses Graduate School 1971 Transition Metal Complexes of Dicyanoacetylene: a Study of the Reaction Chemistry of Low Valence States of the Transition Metals, Platinum, Palladium, Nickel, Rhodium, and Iridium. Gregory Lloyd Mcclure Louisiana State University and Agricultural & Mechanical College Follow this and additional works at: https://digitalcommons.lsu.edu/gradschool_disstheses Recommended Citation Mcclure, Gregory Lloyd, "Transition Metal Complexes of Dicyanoacetylene: a Study of the Reaction Chemistry of Low Valence States of the Transition Metals, Platinum, Palladium, Nickel, Rhodium, and Iridium." (1971). LSU Historical Dissertations and Theses. 2001. https://digitalcommons.lsu.edu/gradschool_disstheses/2001 This Dissertation is brought to you for free and open access by the Graduate School at LSU Digital Commons. It has been accepted for inclusion in LSU Historical Dissertations and Theses by an authorized administrator of LSU Digital Commons. For more information, please contact [email protected]. 71-29,382 McCLURE, Gregory Lloyd, 1993- TRANSITION METAL COMPLEXES OF DICYANOACETYLENE: A STUDY OF THE REACTION CHEMISTRY OF LOW VALENCE STATES OF THE TRANSITION METALS, PLATINUM, PALLADIUM, NICKEL, RHODIUM, AND IRIDIUM. The Louisiana State University and Agricultural and Mechanical College, Ph.D., 1971 C hem i stry, inorgan ic University Microfilms, A XEROX Company , Ann Arbor. Michigan THIS DISSERTATION HAS BEEN MICROFILMED EXACTLY AS RECEIVED TRANSITION -
Nucleophilic Aromatic Substitution on Aryl-Amido Ligands Promoted by Oxidizing Osmium(IV) Centers
Inorg. Chem. 2004, 43, 5804−5815 Nucleophilic Aromatic Substitution on Aryl-Amido Ligands Promoted by Oxidizing Osmium(IV) Centers Jake D. Soper, Erik Saganic, David Weinberg, David A. Hrovat, Jason B. Benedict,† Werner Kaminsky,† and James M. Mayer* Department of Chemistry, Campus Box 351700, UniVersity of Washington, Seattle, Washington 98195-1700 Received January 30, 2004 IV Addition of amine nucleophiles to acetonitrile solutions of the Os anilido complex TpOs(NHPh)Cl2 (1) [Tp ) hydrotris(1-pyrazolyl)borate] gives products with derivatized anilido ligands, i.e., TpOs[NH-p-C6H4(N(CH2)5)]Cl2 (2) from piperidine and TpOs[NH-p-C6H4N(CH2)4]Cl2 (3) from pyrrolidine. These materials are formed in ∼30% yield III under anaerobic conditions, together with ∼60% yields of the Os aniline complex TpOs(NH2Ph)Cl2 (5). Formation of the para-substituted materials 2 or 3 from 1 involves oxidative removal of two hydrogen atoms (two H+ and two - e ). The oxidation can be accomplished by 1, forming 5,orbyO2. Related reactions have been observed with other amines and with the 2-naphthylamido derivative, which gives an ortho-substituted product. Kinetic studies indicate an addition−elimination mechanism involving initial attack of the amine nucleophile on the anilido ligand. These are unusual examples of nucleophilic aromatic substitution of hydrogen. Ab initio calculations on 1 show that the LUMO has significant density at the ortho and para positions of the anilido ligand, resembling the LUMO of nitrobenzene. By analogy with nucleophilic aromatic substitution, 2 is quantitatively formed from piperidine and IV the p-chloroanilide TpOs(NH-p-C6H4Cl)Cl2 (7). -
Synthesis and Transformations of a Few 9-(Pent-4-Yn-1-Yl)Anthracene-Type Systems
The Free Internet Journal Paper for Organic Chemistry Archive for Arkivoc 2018, part vii, 0-0 Organic Chemistry Synthesis and transformations of a few 9-(pent-4-yn-1-yl)anthracene-type systems Eason M. Mathew, Tomson Devassia, Sreedharan Prathapan, and Perupparampil A. Unnikrishnan* Department of Applied Chemistry, CUSAT, Kochi-22, India Email: [email protected] Received 05-24-2018 Accepted 11-04-2018 Published on line 12-27-2018 Abstract 9-(Pent-4-yn-1-yl)anthracene-type compounds can potentially undergo intramolecular Diels-Alder (IMDA) reaction to form 9,11-annulated dibenzobarrelenes. Herein we report the synthesis and IMDA reactions of several heteroatom incorporated 9-(pent-4-yn-1-yl)anthracene-type compounds. Keywords: Dibenzobarrelenes, Intramolecular Diels-Alder (IMDA) reaction, tethered barrelenes, fused-ether, ester, sulfide and sulfone, 1H and 13C NMR DOI: https://doi.org/10.24820/ark.5550190.p010.637 Page 1 ©ARKAT USA, Inc Arkivoc 2018, part vii, 0-0 Mathew, E. M. et al. Introduction Synthesis of bicyclo[2,2,2]octa-2,5,7-triene (barrelene) was first reported by Zimmerman1 et al in 1960. Its barrel-shaped array of molecular orbitals and three ethylene units that are like staves attached to the two methine units attracted the attention of chemists. Synthesis of several barrelene derivatives, especially dibenzobarrelenes, exploited Diels-Alder reaction.2-7 Intramolecular Diels-Alder (IMDA) reaction of suitably substituted anthracenes to give tricyclic systems that may be regarded as annulated barrelenes was first reported by Meek and Dann.8,9 In 1980, Ciganek5 reported a systematic investigation on the synthesis of 9,11- bridged dibenzobarrelene via IMDA reaction (Scheme 1). -
Cycloalkanes, Cycloalkenes, and Cycloalkynes
CYCLOALKANES, CYCLOALKENES, AND CYCLOALKYNES any important hydrocarbons, known as cycloalkanes, contain rings of carbon atoms linked together by single bonds. The simple cycloalkanes of formula (CH,), make up a particularly important homologous series in which the chemical properties change in a much more dramatic way with increasing n than do those of the acyclic hydrocarbons CH,(CH,),,-,H. The cyclo- alkanes with small rings (n = 3-6) are of special interest in exhibiting chemical properties intermediate between those of alkanes and alkenes. In this chapter we will show how this behavior can be explained in terms of angle strain and steric hindrance, concepts that have been introduced previously and will be used with increasing frequency as we proceed further. We also discuss the conformations of cycloalkanes, especially cyclo- hexane, in detail because of their importance to the chemistry of many kinds of naturally occurring organic compounds. Some attention also will be paid to polycyclic compounds, substances with more than one ring, and to cyclo- alkenes and cycloalkynes. 12-1 NOMENCLATURE AND PHYSICAL PROPERTIES OF CYCLOALKANES The IUPAC system for naming cycloalkanes and cycloalkenes was presented in some detail in Sections 3-2 and 3-3, and you may wish to review that ma- terial before proceeding further. Additional procedures are required for naming 446 12 Cycloalkanes, Cycloalkenes, and Cycloalkynes Table 12-1 Physical Properties of Alkanes and Cycloalkanes Density, Compounds Bp, "C Mp, "C diO,g ml-' propane cyclopropane butane cyclobutane pentane cyclopentane hexane cyclohexane heptane cycloheptane octane cyclooctane nonane cyclononane "At -40". bUnder pressure. polycyclic compounds, which have rings with common carbons, and these will be discussed later in this chapter. -
Propellane Units: Extension of Triptindane Chemistry
Canadian Journal of Chemistry A Cyclopenta[hi]acephenanthrylene Bearing Two Benzoannelated [3.3.3]Propellane Units: Extension of Triptindane Chemistry Journal: Canadian Journal of Chemistry Manuscript ID cjc-2016-0498.R1 Manuscript Type: Article Date Submitted by the Author: 12-Nov-2016 Complete List of Authors: Hackfort, Thorsten; Universitat Bielefeld Neumann, DraftBeate; Universitat Bielefeld, Department of Chemistry Stammler, Hans-Georg; Universitat Bielefeld, Department of Chemistry Kuck, Dietmar; Universitat Bielefeld, Department of Chemistry polycyclic aromatic hydrocarbons, phenanthrenes, propellanes, McMurry Keyword: reaction, cyclodehydrogenation https://mc06.manuscriptcentral.com/cjc-pubs Page 1 of 28 Canadian Journal of Chemistry A Cyclopenta[ hi ]acephenanthrylene Bearing Two Benzoannelated [3.3.3]Propellane Units: Extension of Triptindane Chemistry Thorsten Hackfort, [a] Beate Neumann, [a] Hans-Georg Stammler [a] and Dietmar Kuck [a,b] * [a] [b] Department of Chemistry and Center of Molecular Materials (CM 2), Bielefeld University, Universitätsstraße 25, 33615 Bielefeld, Germany Draft *E-mail: [email protected] Tel.: +0049 521 106 2060 Fax: +0049 521 106 6146 Dedicated to Professor Reginald H. Mitchell https://mc06.manuscriptcentral.com/cjc-pubs Canadian Journal of Chemistry Page 2 of 28 - 2 - Abstract. The McMurry reaction of triptindan-9-one (2), a three-fold benzoannelated Cs-symmetrical [3.3.3]propellane ketone, gave trans -9,9’-bitriptindanylidene ( 5), a sterically crowded stilbene hydrocarbon bearing two E-oriented triptindane moieties, in good yield. Photoisomerization of 5 generated the corresponding cis -stilbene 8 in a photostationary E/Z-mixture (55 : 45), which adopts a similarly crowded C2- symmetrical conformation that is apparently static on the NMR timescale. Photocyclodehydrogenation of 5 via 8 in benzene solution afforded the title hydrocarbon 6, a 1,2,9,10-tetrahydrocyclopenta[ hi ]acephenanthrylene merged with two triptindane units, in 85% yield. -
Intermolecular Forces
Intermolecular Forces The intermolecular forces between molecules are important in the properties of all solid and liquid materials. They are key to reactions that take place in biological molecules. Proteins form their secondary and tertiary structures through hydrogen-bonding and London forces. DNA forms because of hydrogen bonding between base pairs. Enzymes function when molecules interact with the protein active site in these biological catalysts. Outline • Types of Intermolecular Forces • Entropy Considerations • Intermolecular Forces and DNA • Homework Types of Intermolecular Forces Solutions consist of a solvent and solute. There are gas, liquid, and solid solutions but in this unit we are concerned with liquids. The solvent then is a liquid phase molecular material that makes up most of the solution. Water is a good example of a solvent. The solute is a smaller quantity of anything that is dissolved in the solvent. It can be a gas (O2 in water), a liquid (water dissolved in ethanol), or a solid (NaCl dissolved in water). In any solution, the molecules or ions of the solute are randomly distributed among the molecules of the solvent. What are the intermolecular forces? They are listed in the table below along with covalent and ionic bonding for comparison. Notice that they have different dependence on the distance between the attracting particles, r. Materials dissolve in a solution when there are strong intermolecular forces between the solute and the solvent. London Dispersion Forces We could discount intermolecular interactions between gas-phase molecules because these molecules are mostly far apart and moving rapidly relative to each other. In the liquid phases, all molecules interact with one another. -
Changes: Physical Or Chemical? by Cindy Grigg
Changes: Physical or Chemical? By Cindy Grigg 1 If you have studied atoms, you know that atoms are the building blocks of matter. Atoms are so small they cannot be seen with an ordinary microscope. Yet atoms make up everything in the universe. Atoms can combine with different atoms and make new substances. Substances can also break apart into separate atoms. These changes are called chemical changes or reactions. Chemical reactions happen when atoms gain, lose, or share electrons. What about when water freezes into ice? Do you think that's a chemical change? 2 When water freezes, it has changed states. You probably already know about the four states of matter. They are solid, liquid, gas, and plasma. Plasma is the fourth state of matter and is the most common state in the universe. However, it is rarely found on Earth. Plasma occurs as ball lightning and in stars. Water is a common substance that everyone has seen in its three states of matter. Water in its solid state is called ice. Water in the liquid state is just called water. Water as a gas is called water vapor. We can easily cause water to change states by changing its temperature. Water will freeze at 32 degrees Fahrenheit (0 Celsius). However, no chemical change has occurred. The atoms have not combined or broken apart to make a different substance; it is still water or H2O. When we heat water to a temperature of 212 F. or 100 Celsius, it will change into a gas called water vapor. Changes in states of matter are just physical changes.