Summaries of FY 1992 Research in the Chemical Sciences
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Polycarbodiimides As Classification-Free and Easy to Use Crosslinkers for Water-Based Coatings
White paper Polycarbodiimides as classification-free and easy to use crosslinkers for water-based coatings By Dr. A.J. Derksen, Stahl International bv, The Netherlands Polycarbodiimides (CDl) selectively react with carboxylic acid (–COOH) groups in polymer chains. This type of crosslinking reaction results in a classic 3D polymer-crosslinker network. Compared to polyisocyanates, polycarbodiimides are much less sensitive to presence of water and able to achieve long pot lives. Due to the high reactivity, curing with CDI type crosslinkers can be done under room temperature or typical oven conditions used for drying of applied coatings. In addition to standard CDI crosslinker chemistry, on offer is also a range of dual reactivity CDI crosslinkers. A second type of reactive groups is attached to the polycarbodiimide in this range. Upon curing, this crosslinker not only reacts with the –COOH groups in the polymer chains, but also two of the reactive groups attached to the separate CDI molecules can couple to form an even denser network structure. Building further on the success of these polycarbodiimide crosslinkers, VOC-free polycarbodiimides, in aqueous delivery form, were introduced, which give extreme long pot lives. 1. Introduction when dealing with flexible substrates. A high level of crosslinking Crosslinking is widely practiced in nearly all the coating may be acceptable for hard coatings on rigid substrates, but industries in order to improve the performance of the coating. low levels may be best for soft coatings on extensible, flexible These improvements include wear, abrasion and chemical substrates such as rubber and leather. An important crosslinking resistances and toughness1. The improved performance originates system for aqueous resins involves the use of water-dispersible from the formation of a continuous three-dimensional network, oligomeric polyisocyanates. -
Cylinder Valve Selection Quick Reference for Valve Abbreviations
SHERWOOD VALVE COMPRESSED GAS PRODUCTS Appendix Cylinder Valve Selection Quick Reference for Valve Abbreviations Use the Sherwood Cylinder Valve Series Abbreviation Chart on this page with the Sherwood Cylinder Valve Selection Charts found on pages 73–80. The Sherwood Cylinder Valve Selection Chart are for reference only and list: • The most commonly used gases • The Compressed Gas Association primary outlet to be used with each gas • The Sherwood valves designated for use with this gas • The Pressure Relief Device styles that are authorized by the DOT for use with these gases PLEASE NOTE: The Sherwood Cylinder Valve Selection Charts are partial lists extracted from the CGA V-1 and S-1.1 pamphlets. They can change without notice as the CGA V-1 and S-1.1 pamphlets are amended. Sherwood will issue periodic changes to the catalog. If there is any discrepancy or question between these lists and the CGA V-1 and S-1.1 pamphlets, the CGA V-1 and S-1.1 pamphlets take precedence. Sherwood Cylinder Valve Series Abbreviation Chart Abbreviation Sherwood Valve Series AVB Small Cylinder Acetylene Wrench-Operated Valves AVBHW Small Cylinder Acetylene Handwheel-Operated Valves AVMC Small Cylinder Acetylene Wrench-Operated Valves AVMCHW Small Cylinder Acetylene Handwheel-Operated Valves AVWB Small Cylinder Acetylene Wrench-Operated Valves — WB Style BV Hi/Lo Valves with Built-in Regulator DF* Alternative Energy Valves GRPV Residual Pressure Valves GV Large Cylinder Acetylene Valves GVT** Vertical Outlet Acetylene Valves KVAB Post Medical Valves KVMB Post Medical Valves NGV Industrial and Chrome-Plated Valves YVB† Vertical Outlet Oxygen Valves 1 * DF Valves can be used with all gases; however, the outlet will always be ⁄4"–18 NPT female. -
Origins of Life: Transition from Geochemistry to Biogeochemistry
December 2016 Volume 12, Number 6 ISSN 1811-5209 Origins of Life: Transition from Geochemistry to Biogeochemistry NITA SAHAI and HUSSEIN KADDOUR, Guest Editors Transition from Geochemistry to Biogeochemistry Staging Life: Warm Seltzer Ocean Incubating Life: Prebiotic Sources Foundation Stones to Life Prebiotic Metal-Organic Catalysts Protometabolism and Early Protocells pub_elements_oct16_1300&icpms_Mise en page 1 13-Sep-16 3:39 PM Page 1 Reproducibility High Resolution igh spatial H Resolution High mass The New Generation Ion Microprobe for Path-breaking Advances in Geoscience U-Pb dating in 91500 zircon, RF-plasma O- source Addressing the growing demand for small scale, high resolution, in situ isotopic measurements at high precision and productivity, CAMECA introduces the IMS 1300-HR³, successor of the internationally acclaimed IMS 1280-HR, and KLEORA which is derived from the IMS 1300-HR³ and is fully optimized for advanced U-Th-Pb mineral dating. • New high brightness RF-plasma ion source greatly improving spatial resolution, reproducibility and throughput • New automated sample loading system with motorized sample height adjustment, significantly increasing analysis precision, ease-of-use and productivity • New UV-light microscope for enhanced optical image resolution (developed by University of Wisconsin, USA) ... and more! Visit www.cameca.com or email [email protected] to request IMS 1300-HR³ and KLEORA product brochures. Laser-Ablation ICP-MS ~ now with CAMECA ~ The Attom ES provides speed and sensitivity optimized for the most demanding LA-ICP-MS applications. Corr. Pb 207-206 - U (238) Recent advances in laser ablation technology have improved signal 2SE error per sample - Pb (206) Combined samples 0.076121 +/- 0.002345 - Pb (207) to background ratios and washout times. -
A Comparative Study of the Formation of Aromatics In
A COMPARATIVE STUDY OF THE FORMATION OF AROMATICS IN RICH METHANE FLAMES DOPED BY UNSATURATED COMPOUNDS H.A. GUENICHE, J. BIET, P.A. GLAUDE, R. FOURNET, F. BATTIN-LECLERC* Département de Chimie-Physique des Réactions, Nancy Université, CNRS, 1 rue Grandville, BP 20451, 54001 NANCY Cedex, France * E-mail : [email protected] ; Tel.: 33 3 83 17 51 25 , Fax : 33 3 83 37 81 20 ABSTRACT For a better modeling of the importance of the different channels leading to the first aromatic ring, we have compared the structures of laminar rich premixed methane flames doped with several unsaturated hydrocarbons: allene and propyne, because they are precursors of propargyl radicals which are well known as having an important role in forming benzene, 1,3-butadiene to put in evidence a possible production of benzene due to reactions of C4 compounds, and, finally, cyclopentene which is a source of cyclopentadienylmethylene radicals which in turn are expected to easily isomerizes to give benzene. These flames have been stabilized on a burner at a pressure of 6.7 kPa (50 Torr) using argon as dilutant, for equivalence ratios (φ) from 1.55 to 1.79. A unique mechanism, including the formation and decomposition of benzene and toluene, has been used to model the oxidation of allene, propyne, 1,3-butadiene and cyclopentene. The main reaction pathways of aromatics formation have been derived from reaction rate and sensitivity analyses and have been compared for the three types of additives. These combined analyses and comparisons can only been performed when a unique mechanism is available for all the studied additives. -
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. -
Metallofullerene and Fullerene Formation from Condensing Carbon Gas Under Conditions of Stellar Outflows and Implication to Star
Metallofullerene and fullerene formation from condensing carbon gas under conditions of stellar outflows and implication to stardust Paul W. Dunka,b,1, Jean-Joseph Adjizianc, Nathan K. Kaiserb, John P. Quinnb, Gregory T. Blakneyb, Christopher P. Ewelsc,1, Alan G. Marshalla,b,1, and Harold W. Krotoa,1 aDepartment of Chemistry and Biochemistry, Florida State University, Tallahassee, FL 32306; bIon Cyclotron Resonance Program, National High Magnetic Field Laboratory, Florida State University, Tallahassee, FL 32310; and cInstitut des Matériaux Jean Rouxel, Centre National de la Recherche Scientifique, Unité Mixte de Recherche 6502, Université de Nantes, BP 32229 Nantes, France Contributed by Harold W. Kroto, August 29, 2013 (sent for review June 13, 2013) Carbonaceous presolar grains of supernovae origin have long confirmed to exist in circumstellar and interstellar environments. been isolated and are determined to be the carrier of anomalous C60 and C70 were first unequivocally detected in a planetary 22Ne in ancient meteorites. That exotic 22Ne is, in fact, the decay nebula in 2010, which was thought to be hydrogen deficient (11). isotope of relatively short-lived 22Na formed by explosive nucleo- Thereafter, Buckminsterfullerene was detected in hydrogen- synthesis, and therefore, a selective and rapid Na physical trapping rich [including the least H-deficient R Coronae Borealis stars] mechanism must take place during carbon condensation in super- (12, 13) and oxygen-rich environments (14), as well as the ISM nova ejecta. Elucidation of the processes that trap Na and produce (15) and a protoplanetary nebula (16). Moreover, fullerenes large carbon molecules should yield insight into carbon stardust have been detected in a host of other circumstellar and in- enrichment and formation. -
High Purity/Recovery Separation of Propylene from Propyne Using Anion Pillared Metal-Organic Framework: Application of Vacuum Swing Adsorption (VSA)
energies Article High Purity/Recovery Separation of Propylene from Propyne Using Anion Pillared Metal-Organic Framework: Application of Vacuum Swing Adsorption (VSA) Majeda Khraisheh 1, Fares AlMomani 1,* and Gavin Walker 2 1 Department of Chemical Engineering, College of Engineering, Qatar University, Doha P.O. Box 2713, Qatar; [email protected] 2 Department of Chemical Sciences, SSPC, Bernal Institute, University of Limerick, V94 T9PX Limerick, Ireland; [email protected] * Correspondence: [email protected]; Tel.: +974-4403-4140 Abstract: Propylene is one of the world’s most important basic olefin raw material used in the produc- tion of a vast array of polymers and other chemicals. The need for high purity grade of propylene is essential and traditionally achieved by the very energy-intensive cryogenic separation. In this study, 2− a pillared inorganic anion SIF6 was used as a highly selective C3H4 due to the square grid pyrazine- based structure. Single gas adsorption revealed a very high C3H4 uptake value (3.32, 3.12, 2.97 and 2.43 mmol·g−1 at 300, 320, 340 and 360 K, respectively). The values for propylene for the same tempera- tures were 2.73, 2.64, 2.31 and 1.84 mmol·g−1, respectively. Experimental results were obtained for the two gases fitted using Langmuir and Toth models. The former had a varied degree of representation of the system with a better presentation of the adsorption of the propylene compared to the propyne system. The Toth model regression offered a better fit of the experimental data over the entire range of pressures. -
NIPPON SHOKUBAI Company Profile
COMPANY PROFILE Osaka Office Kogin Bldg., 4-1-1 Koraibashi, Chuo-ku, Osaka 541-0043, Japan TEL +81-6-6223-9111 FAX +81-6-6201-3716 Tokyo Office Hibiya Dai Bldg., 1-2-2 Uchisaiwai-cho, Chiyoda-ku, Tokyo 100-0011, Japan TEL +81-3-3506-7475 FAX +81-3-3506-7598 https://www.shokubai.co.jp/en/ 2021.6.2000 Nippon Shokubai Group Mission Management Commitment We are deeply dedicated to humanity and the innate human values of sincerity We conduct all of our corporate and honesty. We respect the unique traits and worldview of each individual, embracing diversity and working to promote mutual understanding and trust. activities based upon a deep We recognize that it is the human spirit and point of view that shape our respect for humanity. understanding of management and our actions. A deep respect for humanity is Providing affluence and comfort to people and society, the foundation for all of our corporate activities. with our unique technology We aim at coexisting with We work to create sustainable societies. We believe it is our corporate social society, and working in responsibility to develop positive relationships with all of our stakeholders, as harmony with the environment. well as with the global environment. We pursue technologies We deliver new value that benefits people and society and are dedicated to working as a unified team to develop technology that will open the door to Corporate Credo that will create the future. the future. Safety takes priority over production. By working to expand our business worldwide, we aim to realize our We act on the global stage. -
Formation of Buckminsterfullerene (C60) in Interstellar Space
Formation of buckminsterfullerene ( ) C60 in interstellar space Olivier Berné1 and A. G. G. M. Tielens Leiden Observatory, Leiden University, P.O. Box 9513, NL- 2300 RA Leiden, The Netherlands Edited by Neta A. Bahcall, Princeton University, Princeton, NJ, and approved November 2, 2011 (received for review August 31, 2011) Buckminsterfullerene (C60) was recently confirmed as the largest region, at high angular resolution (Fig. 1). This measurement can molecule identified in space. However, it remains unclear how be used to derive the integrated intensity radiated by the nebula, and where this molecule is formed. It is generally believed that which can be used as a calibrator, to convert the Spitzer observa- C60 is formed from the buildup of small carbonaceous compounds tions of the PAHs and C60 bands into absolute chemical abun- in the hot and dense envelopes of evolved stars. Analyzing infrared dances of these species, allowing a quantitive study of PAH and observations, obtained by Spitzer and Herschel, we found that C60 C60 chemical evolution. is efficiently formed in the tenuous and cold environment of an interstellar cloud illuminated by strong ultraviolet (UV) radiation Measurement of the Far Infrared Integrated Intensity of Dust Emission I fields. This implies that another formation pathway, efficient at in the Nebula. The far infrared integrated intensity FIR was ex- low densities, must exist. Based on recent laboratory and theore- tracted by fitting the spectral energy distribution (SED) at each tical studies, we argue that polycyclic aromatic hydrocarbons are position in the cross-cut shown in Fig. 1. For these positions, we converted into graphene, and subsequently C60, under UV irradia- have used the brightnesses as measured by Herschel Photodetec- tion from massive stars. -
Reactions of Graphene Oxide and Buckminsterfullerene in the Aquatic Environment Yingcan Zhao Purdue University
Purdue University Purdue e-Pubs Open Access Dissertations Theses and Dissertations 8-2016 Reactions of graphene oxide and buckminsterfullerene in the aquatic environment Yingcan Zhao Purdue University Follow this and additional works at: https://docs.lib.purdue.edu/open_access_dissertations Part of the Environmental Engineering Commons Recommended Citation Zhao, Yingcan, "Reactions of graphene oxide and buckminsterfullerene in the aquatic environment" (2016). Open Access Dissertations. 896. https://docs.lib.purdue.edu/open_access_dissertations/896 This document has been made available through Purdue e-Pubs, a service of the Purdue University Libraries. Please contact [email protected] for additional information. Graduate School Form 30 Updated PURDUE UNIVERSITY GRADUATE SCHOOL Thesis/Dissertation Acceptance This is to certify that the thesis/dissertation prepared By Yingcan Zhao Entitled REACTIONS OF GRAPHENE OXIDE AND BUCKMINSTERFULLERENE IN THE AQUATIC ENVIRONMENT For the degree of Doctor of Philosophy Is approved by the final examining committee: Chad T. Jafvert Chair Timothy R. Filley Inez Hua Ronald F. Turco To the best of my knowledge and as understood by the student in the Thesis/Dissertation Agreement, Publication Delay, and Certification Disclaimer (Graduate School Form 32), this thesis/dissertation adheres to the provisions of Purdue University’s “Policy of Integrity in Research” and the use of copyright material. Approved by Major Professor(s): Chad T. Jafvert Approved by: Dulcy M. Abraham 6/21/2016 Head of the Departmental Graduate Program Date i REACTIONS OF GRAPHENE OXIDE AND BUCKMINSTERFULLERENE IN THE AQUATIC ENVIRONMENT A Dissertation Submitted to the Faculty of Purdue University by Yingcan Zhao In Partial Fulfillment of the Requirements for the Degree of Doctor of Philosophy August 2016 Purdue University West Lafayette, Indiana ii To my parents and Liang, for their love, support and encouragement. -
Dimethyl Sulfoxide Oxidation of Primary Alcohols
Western Michigan University ScholarWorks at WMU Master's Theses Graduate College 8-1966 Dimethyl Sulfoxide Oxidation of Primary Alcohols Carmen Vargas Zenarosa Follow this and additional works at: https://scholarworks.wmich.edu/masters_theses Part of the Chemistry Commons Recommended Citation Zenarosa, Carmen Vargas, "Dimethyl Sulfoxide Oxidation of Primary Alcohols" (1966). Master's Theses. 4374. https://scholarworks.wmich.edu/masters_theses/4374 This Masters Thesis-Open Access is brought to you for free and open access by the Graduate College at ScholarWorks at WMU. It has been accepted for inclusion in Master's Theses by an authorized administrator of ScholarWorks at WMU. For more information, please contact [email protected]. DIMETHYL SULFOXIDE OXIDATION OF PRIMARY ALCOHOLS by Carmen Vargas Zenarosa A thesis presented to the Faculty of the School of Graduate Studies in partial fulfillment of the Degree of Master of Arts Western Michigan University Kalamazoo, Michigan August, 1966 ACKNOWLEDGMENTS The author wishes to express her appreciation to the members of her committee, Dr, Don C. Iffland and Dr. Donald C, Berndt, for their helpful suggestions and most especially to Dr, Robert E, Harmon for his patience, understanding, and generous amount of time given to insure the completion of this work. Appreciation is also expressed for the assistance given by her. colleagues. The author acknowledges the assistance given by the National Institutes 0f Health for this research project. Carmen Vargas Zenarosa ii TABLE OF CONTENTS Page -
A Biomimetic Approach to Okilactomycin and Chrolactomycin and the Hexadehydro-Diels–Alder (HDDA) Reaction
A Biomimetic Approach to Okilactomycin and Chrolactomycin and The Hexadehydro-Diels–Alder (HDDA) Reaction A DISSERTATION SUBMITTED TO THE FACULTY OF THE GRADUATE SCHOOL OF THE UNIVERSITY OF MINNESOTA BY Dawen Niu IN PARTIAL FULFILLMENT OF THE REQUIREMENTS FOR THE DEGREE OF DOCTOR OF PHILOSOPHY Thomas R. Hoye December 2013 © Dawen Niu 2013 Acknowledgements So many things could have happened differently in the past 27 years and if any of them had, my career would have taken totally different pathways. I am so glad to be where I am today and need to acknowledge many people that made me here. First of all, I thank my parents. Born in remote villages, neither of them was able to receive good school education. They have been making very little money for what they do. To pay my (and my sister’s) tuition, they chose to work extremely hard. While I was in college, my father worked ca. 12 hours a day and >300 days a year even though he was suffering severe back pain. They tried all they could to make ends meet and yet never complained. But they started to complain after I left for US and stopped asking for tuition. They complain because they aren’t sure if I could get used to the American lifestyle and because they fear my feet will be dragged in US. “Mother worries when son travels a thousand miles.” This recent five years passed really fast to me, but it must have been the longest five years to them. I understand all these better after being a parent myself.