Origins of Life: Transition from Geochemistry to Biogeochemistry
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1 Fundamentals of Polymer Chemistry
1 Fundamentals of Polymer Chemistry H. Warson 1 THE CONCEPT OF A POLYMER 1.1 Historical introduction The differences between the properties of crystalline organic materials of low molecular weight and the more indefinable class of materials referred to by Graham in 1861 as ‘colloids’ has long engaged the attention of chemists. This class includes natural substances such as gum acacia, which in solution are unable to pass through a semi-permeable membrane. Rubber is also included among this class of material. The idea that the distinguishing feature of colloids was that they had a much higher molecular weight than crystalline substances came fairly slowly. Until the work of Raoult, who developed the cryoscopic method of estimating molecular weight, and Van’t Hoff, who enunciated the solution laws, it was difficult to estimate even approximately the polymeric state of materials. It also seems that in the nineteenth century there was little idea that a colloid could consist, not of a product of fixed molecular weight, but of molecules of a broad band of molecular weights with essentially the same repeat units in each. Vague ideas of partial valence unfortunately derived from inorganic chem- istry and a preoccupation with the idea of ring formation persisted until after 1920. In addition chemists did not realise that a process such as ozonisation virtually destroyed a polymer as such, and the molecular weight of the ozonide, for example of rubber, had no bearing on the original molecular weight. The theory that polymers are built up of chain formulae was vigorously advocated by Staudinger from 1920 onwards [1]. -
Ernst Zinner, Lithic Astronomer
UCLA UCLA Previously Published Works Title Ernst Zinner, lithic astronomer Permalink https://escholarship.org/uc/item/0gq43750 Journal Meteoritics & Planetary Science, 42(7/8) ISSN 1086-9379 Author Mckeegan, Kevin D. Publication Date 2007-07-01 Peer reviewed eScholarship.org Powered by the California Digital Library University of California Meteoritics & Planetary Science 42, Nr 7/8, 1045–1054 (2007) Abstract available online at http://meteoritics.org Ernst Zinner, lithic astronomer Kevin D. MCKEEGAN Department of Earth and Space Sciences, University of California, Los Angeles, Los Angeles, California 90095–1567, USA E-mail: [email protected] It is a rare privilege to be one of the founders of an entirely new field of science, and it is especially remarkable when that new field belongs to the oldest branch of “natural philosophy.” The nature of the stars has perplexed and fascinated humanity for millennia. While the sources of their luminosity and their structures and evolution were revealed over the last century, it is thanks to the pioneering efforts of a rare and remarkable man, Ernst Zinner, as well as his colleagues and students (mostly at the University of Chicago and at Washington University in Saint Louis), that in the last two decades it has become possible to literally hold a piece of a star in one’s hand. Armed with sophisticated microscopes and mass spectrometers of various sorts, these “lithic astronomers” are able to reveal stellar processes in exquisite detail by examining the chemical, mineralogical, and especially the nuclear properties of these microscopic grains of stardust. With this special issue of Meteoritics & Planetary Science, we honor Ernst Zinner (Fig. -
Thixotropic Phenomena in Water: Quantitative Indicators of Casimir-Magnetic Transformations from Vacuum Oscillations (Virtual Particles)
Entropy 2015, 17, 6200-6212; doi:10.3390/e17096200 OPEN ACCESS entropy ISSN 1099-4300 www.mdpi.com/journal/entropy Concept Paper Thixotropic Phenomena in Water: Quantitative Indicators of Casimir-Magnetic Transformations from Vacuum Oscillations (Virtual Particles) Michael A. Persinger Biomolecular Sciences and Behavioural Neuroscience Programs, Laurentian University, Sudbury, ON P3E 2C6, Canada; E-Mail: [email protected] Academic Editor: Kevin H. Knuth Received: 15 July 2015 / Accepted: 28 August 2015 / Published: 7 September 2015 Abstract: The ~1.5 × 10−20 J which is considered a universal quantity and is associated with the movement of protons in water also relates to the ratio of the magnetic moment of a proton divided by its unit charge, multiplied by viscosity and applied over the O-H distance. There is quantitative evidence that thixotropy, the “spontaneous” increased viscosity in water when undisturbed, originates from the transformation of virtual particles or vacuum oscillations to real states through conversion of Casimir-magnetic energies that involve the frequency of the neutral hydrogen line and the upper bound threshold value for intergalactic magnetic fields. The results indicate that ½ of a single electron orbit is real (particle) and the other ½ is virtual (wave). The matter equivalent per s for virtual-to-real states for electrons in 1 mL of water with a neutral pH is consistent with the numbers of protons (H+) and the measured range of molecules in the coherent domains for both width and duration of growth and is similar to widths of intergalactic dust grains from which planets and stars may condense. The de Broglie momentum for the lower boundary of the width of coherent domains multiplied by the fine structure velocity of an electron is concurrent with the quantum when one proton is being removed from another and when the upper boundary of the rest mass of a photon is transformed by the product of velocities for putative “entanglement” and light. -
Application of the Photocatalytic Chemistry of Titanium Dioxide to Disinfection and the Killing of Cancer Cells
Separation and Purification Methods Volume 28(1) 1999, pp. 1-50 APPLICATION OF THE PHOTOCATALYTIC CHEMISTRY OF TITANIUM DIOXIDE TO DISINFECTION AND THE KILLING OF CANCER CELLS Daniel M. Blake, Pin-Ching Maness, Zheng Huang, Edward J. Wolfrum, and Jie Huang The National Renewable Laboratory 1617 Cole Boulevard Golden, Colorado 80401-3393 William A. Jacoby Department of Chemical Engineering W2016 Engineering Building East University of Missouri Columbia, MO 65211 Table of Contents Abstract........................................................................................................................... 2 Introduction .................................................................................................................... 2 Background..................................................................................................................... 3 Mode of Action of TiO2................................................................................................... 6 Photocatalytic Reactor Configurations .......................................................................... 9 Structure of Target Organisms....................................................................................... 10 Bacteria...................................................................................................................... 10 Viruses ....................................................................................................................... 13 Fungi......................................................................................................................... -
Preparation of Ti/Tio2 Anode for Electrochemical Oxidation of Toxic Priority Pollutants
Journal of New Materials for Electrochemical Systems 20, 007-012 (2017) © J. New Mat. Electrochem. Systems Preparation of Ti/TiO2 Anode for Electrochemical Oxidation of Toxic Priority Pollutants Asim Yaqub1, Mohamed Hasnain Isa2, Huma Ajab3,*, and Muhammad Junaid4 1Department of Environmental Sciences, COMSATS Institute of Information Technology Abbottabad, KPK Pakistan 2Department of Civil and Environmental Engineering, Universiti Teknologi PETRONAS, Bandar Seri Iskandar 32610, Perak, Malaysia 3Department of Chemistry, COMSATS Institute of Information Technology Abbottabad, Pakistan 4Computer Sciences Department, University of Haripur, KPK Pakistan Received: October 13, 2016, Accepted: January 15, 2017, Available online: April 23, 2017 Abstract: In present study, Ti/TiO2 anodes were prepared in laboratory for degradation of polycyclic aromatic hydrocarbons. Polycyclic aromatic hydrocarbons considered as priority pollutants because of their carcinogenetic properties. PAHs were electrochemically oxidized under galvanostatic conditions using TiO2 coated Ti anode. A synthetic solution containing 16 priority PAHs were prepared in the lab. Surface morphology showed cracked mud structure of coated Ti/TiO2 surface. All the PAHs were efficiently oxidized and degraded from solution. About 96.87% of ƩPAHs were removed in five hours from the bulk solution. The results showed the potential of electrochemical process with Ti/TiO2 anode as a possible and reliable technique for the degradation of PAHs in water. Keywords: Electrochemical; degradation; Ti-TiO2; PAHs PAHs displaying acute carcinogenic, mutagenic and teratogenic properties. Benzo[a]pyrene is recognized as a priority pollutant by Polycyclic Aromatic hydrocarbons (PAHs) are present as pollu- the US Environmental Protection Agency [6] as this compound is tants in air, soil and water. They originate from two main sources known to be one of the most potently carcinogenic of all known natural (biogenic and geochemical) and anthropogenic. -
Titanium Dioxide Derived Materials with Superwettability
catalysts Review Titanium Dioxide Derived Materials with Superwettability Xianfeng Luo 1,2 , Zhongpeng Zhu 3, Ye Tian 1,4,*, Jun You 2 and Lei Jiang 1,3,4,* 1 Key Laboratory of Bio-Inspired Materials and Interfacial Science, Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Beijing 100190, China; [email protected] 2 Key Laboratory of Green Chemical Engineering and Technology of Heilongjiang Province, College of Materials Science and Engineering, Harbin University of Science and Technology, Harbin 150040, China; [email protected] 3 Key Laboratory of Bio-Inspired Smart Interfacial Science and Technology of Ministry of Education, School of Chemistry, Beihang University, Beijing 100191, China; [email protected] 4 School of Future Technology, University of Chinese Academy of Sciences, Beijing 101407, China * Correspondence: [email protected] (Y.T.); [email protected] (L.J.) Abstract: Titanium dioxide (TiO2) is widely used in various fields both in daily life and industry owing to its excellent photoelectric properties and its induced superwettability. Over the past several decades, various methods have been reported to improve the wettability of TiO2 and plenty of practical applications have been developed. The TiO2-derived materials with different morphologies display a variety of functions including photocatalysis, self-cleaning, oil-water separation, etc. Herein, various functions and applications of TiO2 with superwettability are summarized and described in different sections. First, a brief introduction about the discovery of photoelectrodes made of TiO2 is revealed. The ultra-fast spreading behaviors on TiO2 are shown in the part of ultra-fast spreading with superwettability. The part of controllable wettability introduces the controllable wettability Citation: Luo, X.; Zhu, Z.; Tian, Y.; of TiO2-derived materials and their related applications. -
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. -
Origin and Evolution of Carbonaceous Presolar Grains in Stellar Environments
Bernatowicz et al.: Origin and Evolution of Presolar Grains 109 Origin and Evolution of Carbonaceous Presolar Grains in Stellar Environments Thomas J. Bernatowicz Washington University Thomas K. Croat Washington University Tyrone L. Daulton Naval Research Laboratory Laboratory microanalyses of presolar grains provide direct information on the physical and chemical properties of solid condensates that form in the mass outflows from stars. This informa- tion can be used, in conjunction with kinetic models and equilibrium thermodynamics, to draw inferences about condensation sequences, formation intervals, pressures, and temperatures in circumstellar envelopes and in supernova ejecta. We review the results of detailed microana- lytical studies of the presolar graphite, presolar silicon carbide, and nanodiamonds found in primitive meteorites. We illustrate how these investigations, together with astronomical obser- vation and theoretical models, provide detailed information on grain formation and growth that could not be obtained by astronomical observation alone. 1. INTRODUCTION versed the interstellar medium (ISM) prior to their incorpor- ation into the solar nebula, they serve as monitors of physi- In recent years the laboratory study of presolar grains has cal and chemical processing of grains in the ISM (Bernato- emerged as a rich source of astronomical information about wicz et al., 2003). stardust, as well as about the physical and chemical condi- In this review we focus on carbonaceous presolar grains. tions of dust formation in circumstellar -
The Orgueil Meteorite (Atlas of Microfossils)
See discussions, stats, and author profiles for this publication at: https://www.researchgate.net/publication/349917258 The Orgueil meteorite (Atlas of microfossils) Book · October 2020 CITATION READS 1 348 8 authors, including: Richard Brice Hoover Krasavin Eugene The University of Buckingham Joint Institute for Nuclear Research 436 PUBLICATIONS 3,388 CITATIONS 171 PUBLICATIONS 1,121 CITATIONS SEE PROFILE SEE PROFILE Olga Samylina Anton Ryumin Winogradsky Institute Of Microbiology Joint Institute for Nuclear Research 49 PUBLICATIONS 190 CITATIONS 3 PUBLICATIONS 3 CITATIONS SEE PROFILE SEE PROFILE Some of the authors of this publication are also working on these related projects: NAA of Carbonaceous Meteorites View project Radiation DNA damage and DNA double strend break repair and misrepair View project All content following this page was uploaded by Anton Ryumin on 10 March 2021. The user has requested enhancement of the downloaded file. Объединенный институт ядерных исследований Палеонтологический институт им. А.А. Борисяка РАН Институт микробиологии имени С.Н. Виноградского РАН Космический и Ракетный Центр Соединенных Штатов, Хантсвилл, Алабама, США Научный совет РАН по астробиологии МЕТЕОРИТ ОРГЕЙ АТЛАС МИКРОФОССИЛИЙ А.Ю. Розанов, Р.Б. Хувер, Е.А. Красавин, О.С. Самылина, А.К. Рюмин, М.И. Капралов, Е.А. Сапрыкин, А.Н. Афанасьева Объединенный инстиут Палеонтологический институт Институт микробиологии U.S. Space ядерных исследований им. А.А. Борисяка им. С.Н. Виноградского & Rocket Center Российской академии наук Российской академии наук Joint Institute for Nuclear Research A.A. Borissyak Paleontological Institute, Russian Academy of Sciences S.N. Vinogradsky Institute of Microbiology, Russian Academy of Sciences United States Space and Rocket Center, Huntsville, Alabama, USA Scientific Council on Astrobiology, Russian Academy of Sciences THE ORGUEIL METEORITE (ATLAS OF MICROFOSSILS) A. -
Lifetimes of Interstellar Dust from Cosmic Ray Exposure Ages of Presolar Silicon Carbide
Lifetimes of interstellar dust from cosmic ray exposure ages of presolar silicon carbide Philipp R. Hecka,b,c,1, Jennika Greera,b,c, Levke Kööpa,b,c, Reto Trappitschd, Frank Gyngarde,f, Henner Busemanng, Colin Madeng, Janaína N. Ávilah, Andrew M. Davisa,b,c,i, and Rainer Wielerg aRobert A. Pritzker Center for Meteoritics and Polar Studies, The Field Museum of Natural History, Chicago, IL 60605; bChicago Center for Cosmochemistry, The University of Chicago, Chicago, IL 60637; cDepartment of the Geophysical Sciences, The University of Chicago, Chicago, IL 60637; dNuclear and Chemical Sciences Division, Lawrence Livermore National Laboratory, Livermore, CA 94550; ePhysics Department, Washington University, St. Louis, MO 63130; fCenter for NanoImaging, Harvard Medical School, Cambridge, MA 02139; gInstitute of Geochemistry and Petrology, ETH Zürich, 8092 Zürich, Switzerland; hResearch School of Earth Sciences, The Australian National University, Canberra, ACT 2601, Australia; and iEnrico Fermi Institute, The University of Chicago, Chicago, IL 60637 Edited by Mark H. Thiemens, University of California San Diego, La Jolla, CA, and approved December 17, 2019 (received for review March 15, 2019) We determined interstellar cosmic ray exposure ages of 40 large ago. These grains are identified as presolar by their large isotopic presolar silicon carbide grains extracted from the Murchison CM2 anomalies that exclude an origin in the Solar System (13, 14). meteorite. Our ages, based on cosmogenic Ne-21, range from 3.9 ± Presolar stardust grains are the oldest known solid samples 1.6 Ma to ∼3 ± 2 Ga before the start of the Solar System ∼4.6 Ga available for study in the laboratory, represent the small fraction ago. -
Appendix A: Scientific Notation
Appendix A: Scientific Notation Since in astronomy we often have to deal with large numbers, writing a lot of zeros is not only cumbersome, but also inefficient and difficult to count. Scientists use the system of scientific notation, where the number of zeros is short handed to a superscript. For example, 10 has one zero and is written as 101 in scientific notation. Similarly, 100 is 102, 100 is 103. So we have: 103 equals a thousand, 106 equals a million, 109 is called a billion (U.S. usage), and 1012 a trillion. Now the U.S. federal government budget is in the trillions of dollars, ordinary people really cannot grasp the magnitude of the number. In the metric system, the prefix kilo- stands for 1,000, e.g., a kilogram. For a million, the prefix mega- is used, e.g. megaton (1,000,000 or 106 ton). A billion hertz (a unit of frequency) is gigahertz, although I have not heard of the use of a giga-meter. More rarely still is the use of tera (1012). For small numbers, the practice is similar. 0.1 is 10À1, 0.01 is 10À2, and 0.001 is 10À3. The prefix of milli- refers to 10À3, e.g. as in millimeter, whereas a micro- second is 10À6 ¼ 0.000001 s. It is now trendy to talk about nano-technology, which refers to solid-state device with sizes on the scale of 10À9 m, or about 10 times the size of an atom. With this kind of shorthand convenience, one can really go overboard. -
Polymers: a Historical Perspective
Journal & Proceedings of the Royal Society of New South Wales, vol. 152, part 2, 2019, pp. 242–250. ISSN 0035-9173/19/020242-09 Polymers: a historical perspective Robert Burford, FRSN Emeritus Professor, School of Chemical Engineering, UNSW Sydney Email: [email protected] Abstract This commissioned paper outlines the emergence of new forms of synthetics and plastics as our under- standing of polymer chemistry has advanced. Synopsis phenols and styrene are “polymerised” to olymers have been ubiquitous since form thermosets,1 including phenol for- simple gaseous molecules began to form maldehyde “Bakelite” thermosets, but are P 2 life-giving organic structures many millions also present in thermoplastics including of years ago. Today, we rely upon proteins polystyrene and related materials such as comprising twenty amino acids, as well as styrene acrylonitrile (SAN) and ABS.3 The DNA and RNA with many fewer nucleic manufacture of Bakelite is often viewed as acids. Similarly, many fibres and plants the birth of the synthetic polymer industry. comprise carbohydrate polymers: we and The enormous growth both in diversity and other animals use these and protein-based volume of thermoplastics is a feature of the polymers for our diet. Hence, organic earth’s 20th century, dismissively called the “plastics surface has an enormous diversity of natu- age.” Again, important but sometimes ser- rally occurring polymers, sometimes called endipitous discoveries are a feature of this macromolecules. period, but the associated large-scale produc- Today, these continue to feed and clothe tion introduced multinational corporations us, and much more, but the beginning of originating mainly in Europe, the US and man-made materials might be considered Japan.