Fullerenes and Pahs: a Novel Model Explains Their Formation Via
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Carbon Additives for Polymer Compounds
Polymers Carbon Additives for Polymer Compounds Conductive Carbon Black Graphite & Coke www.timcal.com 1 Who are we? TIMCAL Graphite & Carbon has a strong tra- agement and continuous process improve- dition and history in carbon manufacturing. Its ment, all TIMCAL manufacturing plants comply first manufacturing operation was founded in with ISO 9001-2008. 1908. TIMCAL Graphite & Carbon is committed to Today, TIMCAL facilities produce and market a produce highly specialized graphite and car- large variety of synthetic and natural graphite bon materials for today’s and tomorrow’s cus- powders, conductive carbon blacks and water- tomers needs. based dispersions of consistent high quality. TIMCAL Graphite & Carbon is a member of IMERYS, Adhering to a philosophy of Total Quality Man- a world leader in adding value to minerals. Where are we located? With headquarters located in Switzerland, TIMCAL The Group’s industrial and commercial activities Graphite & Carbon has an international pres- are managed by an experienced multinational ence with production facilities and commercial team of more than 430 employees from many offices located in key markets around the globe. countries on three continents. HQ Bodio, Switzerland Willebroek, Belgium Lac-des-Îles, Canada Terrebonne, Canada Graphitization & pro- Manufacturing & pro- Mining, purification and Exfoliation of natural cessing of synthetic cessing of conductive sieving of natural graphite, processing of graphite, manufacturing carbon black graphite flakes natural and synthetic of water-based -
The Synthesis of Novel Cyclohexyne Precursors for an Intramolecular
The Synthesis of Novel Cyclohexyne Precursors for an Intramolecular Pauson-Khand Type Reaction Honors Thesis by Samuel Isaac Etkind In partial fulfillment of the requirements for graduation with the Dean’s Scholars Honors Degree in Chemistry ______________________________ __________________ Stephen F. Martin Date Supervising Professor Table of Contents Acknowledgements ......................................................................................................................... 3 Abstract ........................................................................................................................................... 4 1. Introduction ................................................................................................................................. 5 1.1 The Synthesis and Application of Strained Cycloalkynes .................................................... 5 1.2 The Pauson-Khand Reaction ................................................................................................. 8 1.3 Potential Utility of Cyclohexyne in a Pauson-Khand Reaction .......................................... 11 1.4 Previous Work Towards This Goal ..................................................................................... 13 2. Results ....................................................................................................................................... 17 2.1 Second Generation Approach to Cyclohexyne Precursors ................................................. 17 2.2 Third Generation Approach -
Understanding the Bonding of Second Period Diatomic Molecules Spdf Vs MCAS
Understanding the Bonding of Second Period Diatomic Molecules Spdf vs MCAS By Joel M Williams (text and images © 2013) The html version with updates and higher resolution images is at the author’s website (click here) Abstract The current spdf and MO modeling of chemical molecules are well-established, but do so by continuing to assume that non-classical physics is operating. The MCAS electron orbital model is an alternate particulate model based on classical physics. This paper describes its application to the diatomic molecules of the second period of the periodic table. In doing so, it addresses their molecular electrostatics, bond strengths, and electron affinities. Particular attention is given to the anomalies of the carbon diatom. Questions are raised about the sensibleness of the spdf model’s spatial ability to contain two electrons on an axis between diatoms and its ability to form π-bonds from parallel p-orbitals located over the nuclei of each atom. Nitrogen, carbon monoxide, oxygen, and fluorine all have the same inter-nuclei bonding: all “triple bonds” of varying strength caused by different numbers of anti-bonding electrons. The spdf model was devised for single atoms by physicists and mathematicians. Kowtowing to them, chemists produce hybrid orbitals to explain how atoms could actually form molecules. Drawing these hybrids and meshing them on paper might look great, but, constrained to measured interatomic physical dimensions and electrostatic interactions, bonding based on the spdf-hybrids (sp, sp2, sp3) is illogical. To have even one electron occupy the “bond” region between the nuclei of diatomic molecules, at the expense of reduced coverage elsewhere, does not make sense for stable molecules. -
Carbon Nanomaterials: Building Blocks in Energy Conversion Devices
Mimicking Photosynthesis Carbon nanostructure-based donor- acceptor molecular assemblies can be engineered to mimic natural photo- synthesis. Fullerene C60 is an excellent electron acceptor for the design of donor-bridge-acceptor molecular systems. Photoinduced charge transfer processes in fullerene-based dyads and triads have been extensively investigated by several research groups during the last decade. In these cases the excited C60 accepts an electron from the linked donor group Carbon Nanomaterials: to give the charge-separated state under visible light excitation. Photoinduced charge separation in these dyads has Building Blocks in Energy been achieved using porphyrins, phtha- locyanine, ruthenium complexes, ferro- cene, and anilines as electron donors. Conversion Devices The rate of electron transfer and by Prashant Kamat charge separation efficiency is dependent on the molecular configuration, redox Carbon nanotubes, fullerenes, and mesoporous carbon potential of the donor, and the medium. Clustering the fullerene-donor systems structures constitute a new class of carbon nanomaterials with provides a unique way to stabilize properties that differ signifi cantly from other forms of carbon electron transfer products. The stability of C anions in cluster forms opens such as graphite and diamond. The ability to custom synthesize 60 up new ways to store and transport nanotubes with attached functional groups or to assemble photochemically harnessed charge. fullerene (C60 and analogues) clusters into three-dimensional Novel organic solar cells have (3D) arrays has opened up new avenues to design high surface been constructed by quaternary area catalyst supports and materials with high photochemical self-organization of porphyrin and fullerenes with gold nanoparticles. and electrochemical activity. -
Discharge Plasmas of Molecular Gases
/ J ¥4~r~~~: 'o j~ ~7 ~,~U;~I u t= ~]f~LL*~ ~~~~~~; 4. Isotope Separation in Discharge Plasmas of Molecular Gases EZOUBTCHENKO, Alexandre N.t, AKATSUKA Hiroshi and SUZUKI Masaaki Research Laboratory for Nuclear Reactors, Tokyo Institute of Technology, Tokyo 152-8550, Japan (Received 25 December 1997) Abstract We review the theoretical principles and the experimental methods of isotope separation achieved through the use of discharge plasmas of molecular gases. Isotope separation has been accomplished in various plasma chemical reactions. It is experimentally and theoretically shown that a state of non- equilibrium in the plasmas, especially in the vibrational distribution functions, is essential for the isotope redistribution in the reagents and products. Examples of the reactions, together with the isotope separ- ation factors known up to the present time, are shown to separate isotopic species of carbon, nitrogen and oxygen molecules in the plasma phase, generated by glow discharge and microwave discharge. Keywords: isotope separation, vibrational nonequilibrium, glow discharge, microwave discharge, plasma chemistry 4.1 Introduction isotopic species will be redistributed between the rea- Plasmas generated by electric discharge of molecu- gents and the products. We can elaborate a new lar gases under moderate pressures (10 Torr < p < method of the plasma isotope separation for light ele- 200 Torr) are usually in a state of nonequilibrium. We ments . can define various temperatures according to the kine- There were a few experimental studies of isotope tics of various particles in such plasmas, for example, separation phenomena in the nonequilibrium electric electron temperature ( T*), gas translational temperature discharge. Semiokhin et al. measured C02 enrichment ( To), gas rotational temperature ( TR) and vibrational in i3C02 and 12C160180 with a separation factor a ~ temperature ( Tv), where the relationships T* > Tv ;~ 1.01 in the C02 Silent (barrier) discharge in the pres- TR- To usually hold. -
©2018 Alexander Hook ALL RIGHTS RESERVED
©2018 Alexander Hook ALL RIGHTS RESERVED A DFT STUDY OF HYDROGEN ABSTRACTION FROM LIGHT ALKANES: Pt ALLOY DEHYDROGENATION CATALYSTS AND TIO2 STEAM REFORMING CATALYSTS By ALEXANDER HOOK A dissertation submitted to the School of Graduate Studies Rutgers, The State University of New Jersey In partial fulfillment of the requirements For the degree of Doctor of Philosophy Graduate Program in Chemical and Biochemical Engineering Written under the direction of Fuat E. Celik And approved by __________________________ __________________________ __________________________ __________________________ New Brunswick, New Jersey May, 2018 ABSTRACT OF THE DISSERTATION A DFT STUDY OF HYDROGEN ABSTRACTION FROM LIGHT ALKANES: Pt ALLOY DEHYDROGENATION CATALYSTS AND TiO2 STEAM REFORMING CATALYSTS By ALEC HOOK Dissertation Director: Fuat E. Celik Sustainable energy production is one of the biggest challenges of the 21st century. This includes effective utilization of carbon-neutral energy resources as well as clean end-use application that do not emit CO2 and other pollutants. Hydrogen gas can potentially solve the latter problem, as a clean burning fuel with very high thermodynamic energy conversion efficiency in fuel cells. In this work we will be discussing two methods of obtaining hydrogen. The first is as a byproduct of light alkane dehydrogenation where we obtain a high value olefin along with hydrogen gas. The second is in methane steam reforming where hydrogen is the primary product. Chapter 1 begins by introducing the reader to the current state of the energy industry. Afterwards there is an overview of what density functional theory (DFT) is and how this computational technique can elucidate and complement laboratory experiments. It will also contain the general parameters and methodology of the VASP software package that runs the DFT calculations. -
Hazardous Substance Fact Sheet
Right to Know Hazardous Substance Fact Sheet Common Name: CARBON BLACK Synonyms: C.I. Pigment Black 7; Channel Black; Lamp Black CAS Number: 1333-86-4 Chemical Name: Carbon Black RTK Substance Number: 0342 Date: December 2007 Revision: November 2016 DOT Number: UN 1361 Description and Use EMERGENCY RESPONDERS >>>> SEE BACK PAGE Carbon Black is black, odorless, finely divided powder Hazard Summary generated from the incomplete combustion of Hydrocarbons. It Hazard Rating NJDOH NFPA may contain Polycyclic Aromatic Hydrocarbons (PAHs) which HEALTH 3 - are formed during its manufacture and become adsorbed on FLAMMABILITY 1 - the Carbon Black. It is used in making tire treads, in abrasion REACTIVITY 0 - resistant rubber products, and as a pigment for paints and inks. CARCINOGEN SPONTANEOUSLY COMBUSTIBLE PARTICULATE POISONOUS GASES ARE PRODUCED IN FIRE Reasons for Citation Hazard Rating Key: 0=minimal; 1=slight; 2=moderate; 3=serious; Carbon Black is on the Right to Know Hazardous 4=severe Substance List because it is cited by OSHA, ACGIH, NIOSH and IARC. Carbon Black can affect you when inhaled. This chemical is on the Special Health Hazard Substance Carbon Black should be handled as a CARCINOGEN-- List as it is considered a carcinogen. WITH EXTREME CAUTION. Contact can irritate the skin and eyes. Inhaling Carbon Black can irritate the nose, throat and lungs. Finely dispersed Carbon Black particles may form explosive mixtures in air. SEE GLOSSARY ON PAGE 5. FIRST AID Workplace Exposure Limits Eye Contact OSHA: The legal airborne permissible exposure limit (PEL) is Immediately flush with large amounts of water for at least 15 3.5 mg/m3 averaged over an 8-hour workshift. -
Stabilization of Anti-Aromatic and Strained Five-Membered Rings with A
ARTICLES PUBLISHED ONLINE: 23 JUNE 2013 | DOI: 10.1038/NCHEM.1690 Stabilization of anti-aromatic and strained five-membered rings with a transition metal Congqing Zhu1, Shunhua Li1,MingLuo1, Xiaoxi Zhou1, Yufen Niu1, Minglian Lin2, Jun Zhu1,2*, Zexing Cao1,2,XinLu1,2, Tingbin Wen1, Zhaoxiong Xie1,Paulv.R.Schleyer3 and Haiping Xia1* Anti-aromatic compounds, as well as small cyclic alkynes or carbynes, are particularly challenging synthetic goals. The combination of their destabilizing features hinders attempts to prepare molecules such as pentalyne, an 8p-electron anti- aromatic bicycle with extremely high ring strain. Here we describe the facile synthesis of osmapentalyne derivatives that are thermally viable, despite containing the smallest angles observed so far at a carbyne carbon. The compounds are characterized using X-ray crystallography, and their computed energies and magnetic properties reveal aromatic character. Hence, the incorporation of the osmium centre not only reduces the ring strain of the parent pentalyne, but also converts its Hu¨ckel anti-aromaticity into Craig-type Mo¨bius aromaticity in the metallapentalynes. The concept of aromaticity is thus extended to five-membered rings containing a metal–carbon triple bond. Moreover, these metal–aromatic compounds exhibit unusual optical effects such as near-infrared photoluminescence with particularly large Stokes shifts, long lifetimes and aggregation enhancement. romaticity is a fascinating topic that has long interested Results and discussion both experimentalists and theoreticians because of its ever- Synthesis, characterization and reactivity of osmapentalynes. Aincreasing diversity1–5. The Hu¨ckel aromaticity rule6 applies Treatment of complex 1 (ref. 32) with methyl propiolate to cyclic circuits of 4n þ 2 mobile electrons, but Mo¨bius topologies (HC;CCOOCH3) at room temperature produced osmapentalyne favour 4n delocalized electron counts7–10. -
Chapter 10 Theories of Electronic Molecular Structure
Chapter 10 Theories of Electronic Molecular Structure Solving the Schrödinger equation for a molecule first requires specifying the Hamiltonian and then finding the wavefunctions that satisfy the equation. The wavefunctions involve the coordinates of all the nuclei and electrons that comprise the molecule. The complete molecular Hamiltonian consists of several terms. The nuclear and electronic kinetic energy operators account for the motion of all of the nuclei and electrons. The Coulomb potential energy terms account for the interactions between the nuclei, the electrons, and the nuclei and electrons. Other terms account for the interactions between all the magnetic dipole moments and the interactions with any external electric or magnetic fields. The charge distribution of an atomic nucleus is not always spherical and, when appropriate, this asymmetry must be taken into account as well as the relativistic effect that a moving electron experiences as a change in mass. This complete Hamiltonian is too complicated and is not needed for many situations. In practice, only the terms that are essential for the purpose at hand are included. Consequently in the absence of external fields, interest in spin- spin and spin-orbit interactions, and in electron and nuclear magnetic resonance spectroscopy (ESR and NMR), the molecular Hamiltonian usually is considered to consist only of the kinetic and potential energy terms, and the Born- Oppenheimer approximation is made in order to separate the nuclear and electronic motion. In general, electronic wavefunctions for molecules are constructed from approximate one-electron wavefunctions. These one-electron functions are called molecular orbitals. The expectation value expression for the energy is used to optimize these functions, i.e. -
Acid-Base Properties of Carbon Black Surfaces Roy Eugene Test Iowa State University
View metadata, citation and similar papers at core.ac.uk brought to you by CORE provided by Digital Repository @ Iowa State University Ames Laboratory Technical Reports Ames Laboratory 5-1961 Acid-base properties of carbon black surfaces Roy Eugene Test Iowa State University Robert S. Hansen Iowa State University Follow this and additional works at: http://lib.dr.iastate.edu/ameslab_isreports Part of the Chemistry Commons Recommended Citation Test, Roy Eugene and Hansen, Robert S., "Acid-base properties of carbon black surfaces" (1961). Ames Laboratory Technical Reports. 43. http://lib.dr.iastate.edu/ameslab_isreports/43 This Report is brought to you for free and open access by the Ames Laboratory at Iowa State University Digital Repository. It has been accepted for inclusion in Ames Laboratory Technical Reports by an authorized administrator of Iowa State University Digital Repository. For more information, please contact [email protected]. Acid-base properties of carbon black surfaces Abstract The urs face properties of carbon blacks reflect not only Van der Waals forces due to carbon, but also chemical properties of groups formed on carbon black surfaces by reactions with environmental substances (e.g. water, oxygen, etc.). The present work constitutes a study of such groups. Disciplines Chemistry This report is available at Iowa State University Digital Repository: http://lib.dr.iastate.edu/ameslab_isreports/43 I IS-341 ACID-BASE PROPERTIES OF CARBON BLACK SURFACES By Roy Eugene Test Robert S. Hansen May 196 1 Ames Laboratory Iowa State University I Ames, Iowa :· : :· .. : :· :. ': •. :· ·:· ·:: .: •. :' . :, ·: :· ': F. H. Spedding, Director, Ames Laboratory. Work performed under Contract No. W-7405-eng-82. -
Defence Applications of New Forms of Carbon
FOI-R--1103--SE December 2003 ISSN 1650-1942 Base data report S.J. Savage Defence applications of new forms of carbon Schematic model of the C60 fullerene molecule (Fagerström, 2003) Sensor Technology SE-581 11 Linköping SWEDISH DEFENCE RESEARCH AGENCY FOI-R--1103--SE Sensor Technology December 2003 P.O. Box 1165 ISSN 1650-1942 SE-581 11 Linköping Base data report S.J. Savage Defence applications of new forms of carbon Issuing organization Report number, ISRN Report type FOI – Swedish Defence Research Agency FOI-R--1103--SE Base data report Sensor Technology Research area code P.O. Box 1165 7. Vehicles SE-581 11 Linköping Month year Project no. December 2003 E3037 Customers code 5. Commissioned Research Sub area code 74 Materials technology Author/s (editor/s) Project manager S.J. Savage S.J. Savage Approved by Sponsoring agency Scientifically and technically responsible Report title Defence applications of new forms of carbon Abstract (not more than 200 words) This report briefly reviews some applications of new forms of carbon (fullerenes, carbon nanotubes and nanofibres) in military technology. Selected reports are summarised and discussed, and a number of military applications suggested. The report contains recommendations for future studies. Keywords nanotechnology, carbon, defence applications, nanotubes, fullerenes Further bibliographic information Language English ISSN 1650-1942 Pages 15 p. Price acc. to pricelist 2 Utgivare Rapportnummer, ISRN Klassificering Totalförsvarets Forskningsinstitut - FOI FOI-R--1103--SE Underlagsrapport Sensorteknik Forskningsområde Box 1165 7. Farkoster 581 11 Linköping Månad, år Projektnummer December 2003 E3037 Verksamhetsgren 5. Uppdragsfinansierad verksamhet Delområde 74 Materialteknik Författare/redaktör Projektledare S.J. -
A Post-Buckminsterfullerene View of Carbon Chemistry
A POST-BUCKMINSTERFULLERENE VIEW OF CARBON CHEMISTRY Harold Kroto School of Chemistry and Molecular Sciences, University of Sussex, Brighton, BNI 9QJ UK Keywords: Cs0, Fullerenes, carbon particles INTRODUCTION The discovery of c60 Buckminsterfullerene, Fig 1, has its origins in a research programme involving synthetic chemistry, microwave spectroscopy and radioastronomyl. In 1915, at Sussex (with David Walton), the long chain polyyne H-CeC-CsC-CsN was synthesised and studied by microwave spectroscopy. Subsequently, with Takeshi Oka and NRC(0ttawa) astronomers, the molecule was discovered in space, Fig 2, by radioastronomy using the laboratory microwave frequencies. This discovery led on to the detection of the even longer carbon chain molecules HCTN, HCgN and HCl.lN in the space between the stars2. Further work aimed at understanding the formation of the chains in space focussed attention on the possibility that they are produced at the same time as carbon dust in red giant stars1,*. During experiments at Rice University in 1985 (with James Heath, Sean O'Brien, Robert Curl and Richard Smalley), designed to simulate the conditions in these stars and explore their capacity for carbon chain formation, the exciting discovery that C60 was remarkably stable was made3. It was found that under conditions where almost all the atoms in a carbon plasma had nucleated to form microparticles the molecule c60 remained behind - together with some CTO. This result was, as is now well 'known, rationalised on the basis of the closed cage structure shown in Fig 1. It was proposed that the geodesic and aromatic factors inherent in such a structure could account for the stability of the molecule.