Physical Processes in the Interstellar Medium
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Selective Production of Phase-Separable Product from a Mixture of Biomass-Derived Aqueous Oxygenates
ARTICLE DOI: 10.1038/s41467-018-07593-0 OPEN Selective production of phase-separable product from a mixture of biomass-derived aqueous oxygenates Yehong Wang 1, Mi Peng2, Jian Zhang1, Zhixin Zhang1, Jinghua An1,3, Shuyan Du1, Hongyu An1,3, Fengtao Fan1, Xi Liu 4,5, Peng Zhai2, Ding Ma 2 & Feng Wang1 1234567890():,; Selective conversion of an aqueous solution of mixed oxygenates produced by biomass fermentation to a value-added single product is pivotal for commercially viable biomass utilization. However, the efficiency and selectivity of the transformation remains a great challenge. Herein, we present a strategy capable of transforming ~70% of carbon in an aqueous fermentation mixture (ABE: acetone–butanol–ethanol–water) to 4-heptanone (4- HPO), catalyzed by tin-doped ceria (Sn-ceria), with a selectivity as high as 86%. Water (up to 27 wt%), detrimental to the reported catalysts for ABE conversion, was beneficial for producing 4-HPO, highlighting the feasibility of the current reaction system. In a 300 h continuous reaction over 2 wt% Sn-ceria catalyst, the average 4-HPO selectivity is main- tained at 85% with 50% conversion and > 90% carbon balance. This strategy offers a route for highly efficient organic-carbon utilization, which can potentially integrate biological and chemical catalysis platforms for the robust and highly selective production of value-added chemicals. 1 State Key Laboratory of Catalysis, Dalian National Laboratory for Clean Energy, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China. 2 College of Chemistry and Molecular Engineering and College of Engineering, BIC-ESAT, Peking University, Beijing 100871, China. -
145, September 2010
British Astronomical Association VARIABLE STAR SECTION CIRCULAR No 145, September 2010 Contents EG Andromedae Light Curve ................................................... inside front cover From the Director ............................................................................................... 1 Letter Page. Visual Observing ............................................................................ 4 Epsilon Aurigae Spectroscopically at Mid Eclipse .......................................... 5 Eclipsing Binary News ...................................................................................... 7 AO Cassiopeiae Phase Diagram ............................................................ 9 PV Cephei and Gyulbudaghian’s Nebula ........................................................ 10 WR140 Periastron Campaign Update .............................................................. 12 VSS Meeting, Pendrell Hall. The Central Stars of Planetary Nebulae ............ 14 RR Coronae Borealis 1993-2004 ...................................................................... 16 TU Cassiopeiae Phase Diagram 2005-2010 ..................................................... 18 Binocular Priority List ..................................................................................... 19 Eclipsing Binary Predictions ............................................................................ 20 Charges for Section Publications .............................................. inside back cover Guidelines for Contributing to the Circular ............................. -
John J. Cowan Date of Birth: April 3, 1948 Place of Birth: Washington, D.C
VITA NAME: John J. Cowan Date of Birth: April 3, 1948 Place of Birth: Washington, D.C. EDUCATION: 1970 B.A. George Washington University, Washington, D.C. 1972 M.S. Case Institute of Technology, Cleveland, OH 1976 Ph.D. University of Maryland, College Park, MD PROFESSIONAL EXPERIENCE: 2002–present David Ross Boyd Professor, University of Oklahoma, 2002–2002 Research Fellow, University of Texas, Austin, TX 1998–2002 Samuel Roberts Noble Foundation Presidential Professor, University of Oklahoma, Norman, OK 1997–1998 Big XIIFaculty Fellow,University ofOklahoma 1991–1992 Visiting Professor, Department of Astronomy, Columbia University, New York, NY 1989–present Professor, Department of Physics and Astronomy, University of Oklahoma, Norman, OK 1988–1994 Consultant and Participating Guest, Lawrence Livermore National Laboratory, Livermore, CA 1987–1988 Visiting Research Associate, Harvard-Smithsonian Center for Astrophysics, Harvard University, Cambridge, MA 1984–1989 Associate Professor, University of Oklahoma 1979–1984 Assistant Professor, University of Oklahoma 1976–1979 Postdoctoral Research Fellow, Harvard-Smithsonian Center for Astrophysics, Harvard University PROFESSIONAL AND HONORARY SOCIETIES: American Astronomical Society International Astronomical Union Phi Beta Kappa RESEARCH INTERESTS: Stellar evolution, supernovae, nucleosynthesis and abundances Radio observations of supernovae and galaxies JOHN J. COWAN Page 2 PUBLICATIONS J. J. Cowan and W. K. Rose, “Production of 17O and 18O by Means of the Hot CNO Tri-Cycle,” Astrophys. J. (Letters) 201, L45 (1975) J. J. Cowan, M. Kafatos, and W. K. Rose, “Sources of Excitation of the Interstellar Gas and Galactic Structure,” Astrophys. J. 195, 47 (1975) M. F. A’Hearn and J. J. Cowan, “Molecular Production Rates in Comet Kohoutek,” As- tron. -
Alyssa Goodman, Naomi Ridge, Scott Wolk, Scott Schnee, Di Li & Bryan
COMPLET(E)ING THE STAR-FORMATION HISTORY OF THE RHO-OPH REGION Alyssa Goodman, Naomi Ridge, Scott Wolk, Scott Schnee, Di Li & Bryan Gaensler Background The interaction of newly formed stars with their parent cloud, particularly in the case of massive stars, can have significant consequences for the subsequent development of the cloud. Hot, massive stars will cause cloud disruption through their ionizing flux as well as through the momentum in their stellar winds. Alternatively, given the right conditions in the cloud, stellar winds may also cause the collapse of cloud cores and induce further star formation. Located only 160pc from the Sun, the Ophiuchus molecular cloud is one of the most conspicuous nearby regions where low- and intermediate-mass star formation is taking place (e.g. Wilking 1992 for a review). The Ophiuchus cloud consists of two massive, centrally condensed cores, L1688 and L1689, from each of which a filamentary system of streamers extends to the north-east over tens of parsecs (e.g. Loren 1989). While little star formation activity is observed in the streamers, the westernmost core, L1688 (figure 1), harbors a rich cluster of young stellar objects (YSOs) at various evolutionary stages and is distinguished by a high star-formation efficiency (Wilking & Lada 1983 - hereafter WL83). This young stellar cluster and the cloud core in which it resides are commonly referred to as the ρ-Oph star-forming region. Both the gas/dust content and the embedded stellar population of ρ−Oph have been extensively studied for more than two decades. The distribution of the low-density molecular gas was mapped in C18O(1-0) by WL83, revealing a ridge of high column density gas. -
Winter Constellations
Winter Constellations *Orion *Canis Major *Monoceros *Canis Minor *Gemini *Auriga *Taurus *Eradinus *Lepus *Monoceros *Cancer *Lynx *Ursa Major *Ursa Minor *Draco *Camelopardalis *Cassiopeia *Cepheus *Andromeda *Perseus *Lacerta *Pegasus *Triangulum *Aries *Pisces *Cetus *Leo (rising) *Hydra (rising) *Canes Venatici (rising) Orion--Myth: Orion, the great hunter. In one myth, Orion boasted he would kill all the wild animals on the earth. But, the earth goddess Gaia, who was the protector of all animals, produced a gigantic scorpion, whose body was so heavily encased that Orion was unable to pierce through the armour, and was himself stung to death. His companion Artemis was greatly saddened and arranged for Orion to be immortalised among the stars. Scorpius, the scorpion, was placed on the opposite side of the sky so that Orion would never be hurt by it again. To this day, Orion is never seen in the sky at the same time as Scorpius. DSO’s ● ***M42 “Orion Nebula” (Neb) with Trapezium A stellar nursery where new stars are being born, perhaps a thousand stars. These are immense clouds of interstellar gas and dust collapse inward to form stars, mainly of ionized hydrogen which gives off the red glow so dominant, and also ionized greenish oxygen gas. The youngest stars may be less than 300,000 years old, even as young as 10,000 years old (compared to the Sun, 4.6 billion years old). 1300 ly. 1 ● *M43--(Neb) “De Marin’s Nebula” The star-forming “comma-shaped” region connected to the Orion Nebula. ● *M78--(Neb) Hard to see. A star-forming region connected to the Orion Nebula. -
Správa O Činnosti Organizácie SAV Za Rok 2017
Astronomický ústav SAV Správa o činnosti organizácie SAV za rok 2017 Tatranská Lomnica január 2018 Obsah osnovy Správy o činnosti organizácie SAV za rok 2017 1. Základné údaje o organizácii 2. Vedecká činnosť 3. Doktorandské štúdium, iná pedagogická činnosť a budovanie ľudských zdrojov pre vedu a techniku 4. Medzinárodná vedecká spolupráca 5. Vedná politika 6. Spolupráca s VŠ a inými subjektmi v oblasti vedy a techniky 7. Spolupráca s aplikačnou a hospodárskou sférou 8. Aktivity pre Národnú radu SR, vládu SR, ústredné orgány štátnej správy SR a iné organizácie 9. Vedecko-organizačné a popularizačné aktivity 10. Činnosť knižnično-informačného pracoviska 11. Aktivity v orgánoch SAV 12. Hospodárenie organizácie 13. Nadácie a fondy pri organizácii SAV 14. Iné významné činnosti organizácie SAV 15. Vyznamenania, ocenenia a ceny udelené organizácii a pracovníkom organizácie SAV 16. Poskytovanie informácií v súlade so zákonom o slobodnom prístupe k informáciám 17. Problémy a podnety pre činnosť SAV PRÍLOHY A Zoznam zamestnancov a doktorandov organizácie k 31.12.2017 B Projekty riešené v organizácii C Publikačná činnosť organizácie D Údaje o pedagogickej činnosti organizácie E Medzinárodná mobilita organizácie F Vedecko-popularizačná činnosť pracovníkov organizácie SAV Správa o činnosti organizácie SAV 1. Základné údaje o organizácii 1.1. Kontaktné údaje Názov: Astronomický ústav SAV Riaditeľ: Mgr. Martin Vaňko, PhD. Zástupca riaditeľa: Mgr. Peter Gömöry, PhD. Vedecký tajomník: Mgr. Marián Jakubík, PhD. Predseda vedeckej rady: RNDr. Luboš Neslušan, CSc. Člen snemu SAV: Mgr. Marián Jakubík, PhD. Adresa: Astronomický ústav SAV, 059 60 Tatranská Lomnica http://www.ta3.sk Tel.: 052/7879111 Fax: 052/4467656 E-mail: [email protected] Názvy a adresy detašovaných pracovísk: Astronomický ústav - Oddelenie medziplanetárnej hmoty Dúbravská cesta 9, 845 04 Bratislava Vedúci detašovaných pracovísk: Astronomický ústav - Oddelenie medziplanetárnej hmoty prof. -
The Tritium Beta-Ray Induced Reactions in Deuterium Oxide Vapor and Hydrogen Or Carbon Monoxide and the Exchange of H-Atoms with Water Molecules
This dissertation has been microfilmed exactly as received 66-6232 BIBLER, Ned Eugene, 1937- THE TRITIUM BETA-RAY INDUCED REACTIONS IN DEUTERIUM OXIDE VAPOR AND HYDROGEN OR CARBON MONOXIDE AND THE EXCHANGE OF H-ATOMS WITH WATER MOLECULES. The Ohio State University, Ph.D., 1965 Chemistry, physical University Microfilms, Inc., Ann Arbor, Michigan THE TRITIUM 3ETA-RAY INDUCED REACTIONS IN DEUTERIUM OXIDE VAPOR AND HYDROGEN OR CARBON MONOXIDE AND THE EXCHANGE OF H-ATOMS WITH WATER MOLECULES DISSERTATION Presented in Partial Fulfillment of the Requirements for the Degree Doctor of Philosophy in the Graduate School of The Ohio State University By Ned Eugene B ib le r , B .S ., M.S * * * * * The Ohio S ta te U n iversity 1965 Approved by Adviser Department of Chemistry ACKNOWLEDGMENTS Several groups were influential in the completion of this work and the culmination of my graduate career at the Ohio State University. I have singled out two who deserve special acknowledg ment. I wish to express my appreciation to the members of my family for their understanding and sympathetic guidance during this demanding period. In particular, I thank my wife, Jane, who was a source of encouragement, for her devotion, scientific advice, and unswervingly honest criticism ; and my mother in law, Mrs. Pauline Pycraft, who typed a major portion of the first draft of this thesis. I am indebted to the stimulating research group headed by Dr. R. F. Firestone for many fruitful discussions and altercations on an array of subjects, including the radiation chemistry of water vapor. Specifically, I thank Dr. Firestone for his keen interest and set of high scientific standards which, when applied to the course and completion of this study, made it a maturing and g r a tify in g experience. -
Wynyard Planetarium & Observatory a Autumn Observing Notes
Wynyard Planetarium & Observatory A Autumn Observing Notes Wynyard Planetarium & Observatory PUBLIC OBSERVING – Autumn Tour of the Sky with the Naked Eye CASSIOPEIA Look for the ‘W’ 4 shape 3 Polaris URSA MINOR Notice how the constellations swing around Polaris during the night Pherkad Kochab Is Kochab orange compared 2 to Polaris? Pointers Is Dubhe Dubhe yellowish compared to Merak? 1 Merak THE PLOUGH Figure 1: Sketch of the northern sky in autumn. © Rob Peeling, CaDAS, 2007 version 1.2 Wynyard Planetarium & Observatory PUBLIC OBSERVING – Autumn North 1. On leaving the planetarium, turn around and look northwards over the roof of the building. Close to the horizon is a group of stars like the outline of a saucepan with the handle stretching to your left. This is the Plough (also called the Big Dipper) and is part of the constellation Ursa Major, the Great Bear. The two right-hand stars are called the Pointers. Can you tell that the higher of the two, Dubhe is slightly yellowish compared to the lower, Merak? Check with binoculars. Not all stars are white. The colour shows that Dubhe is cooler than Merak in the same way that red-hot is cooler than white- hot. 2. Use the Pointers to guide you upwards to the next bright star. This is Polaris, the Pole (or North) Star. Note that it is not the brightest star in the sky, a common misconception. Below and to the left are two prominent but fainter stars. These are Kochab and Pherkad, the Guardians of the Pole. Look carefully and you will notice that Kochab is slightly orange when compared to Polaris. -
1 Kepler's Third
Astronomy 114 { Summary of Important Concepts #1 1 1 Kepler's Third Law Kepler discovered that the size of a planet's orbit (the semi-major axis of the ellipse) is simply related to sidereal period of the orbit. If the size of the orbit (a) is expressed in astronomical units (1 AU equals the average distance between the Earth and Sun) and the period (P) is measured in years, then Kepler's Third Law says P 2 = a3: After applying Newton's Laws of Motion and Newton's Law of Gravity we find that Kepler's Third Law takes a more general form: 4π2 P 2 = a3 "G(m1 + m2)# in MKS units where m1 and m2 are the masses of the two bodies. Let's assume that one body, m1 say, is always much larger than the other one. Then m1 + m2 is nearly equal to m1. We can then use our technique of dividing two instances of this equation derive a general form of Kepler's Third Law: MP 2 = a3 where P is in Earth years, a is in AU and M is the mass of the central object in units of the mass of the Sun. So M = 1 whenever we talk about planets orbiting the Sun. Examples: Q: The Earth orbits the Sun at a distance of 1AU with a period of 1 year. 12 = 13. Suppose a new asteroid is discovered which orbits the Sun at a distance of 9AU. How long does it take this object to orbit the Sun? A: MP 2 = a3 (1)(P 2) = 93 P 2 = 729 P = p729 = 27 years Astronomy 114 { Summary of Important Concepts #1 2 2 Newton's Law of Gravitation Any two objects, no matter how small, attract one another gravitationally. -
Apparent and Absolute Magnitudes of Stars: a Simple Formula
Available online at www.worldscientificnews.com WSN 96 (2018) 120-133 EISSN 2392-2192 Apparent and Absolute Magnitudes of Stars: A Simple Formula Dulli Chandra Agrawal Department of Farm Engineering, Institute of Agricultural Sciences, Banaras Hindu University, Varanasi - 221005, India E-mail address: [email protected] ABSTRACT An empirical formula for estimating the apparent and absolute magnitudes of stars in terms of the parameters radius, distance and temperature is proposed for the first time for the benefit of the students. This reproduces successfully not only the magnitudes of solo stars having spherical shape and uniform photosphere temperature but the corresponding Hertzsprung-Russell plot demonstrates the main sequence, giants, super-giants and white dwarf classification also. Keywords: Stars, apparent magnitude, absolute magnitude, empirical formula, Hertzsprung-Russell diagram 1. INTRODUCTION The visible brightness of a star is expressed in terms of its apparent magnitude [1] as well as absolute magnitude [2]; the absolute magnitude is in fact the apparent magnitude while it is observed from a distance of . The apparent magnitude of a celestial object having flux in the visible band is expressed as [1, 3, 4] ( ) (1) ( Received 14 March 2018; Accepted 31 March 2018; Date of Publication 01 April 2018 ) World Scientific News 96 (2018) 120-133 Here is the reference luminous flux per unit area in the same band such as that of star Vega having apparent magnitude almost zero. Here the flux is the magnitude of starlight the Earth intercepts in a direction normal to the incidence over an area of one square meter. The condition that the Earth intercepts in the direction normal to the incidence is normally fulfilled for stars which are far away from the Earth. -
On the Detection of Exoplanets Via Radial Velocity Doppler Spectroscopy
The Downtown Review Volume 1 Issue 1 Article 6 January 2015 On the Detection of Exoplanets via Radial Velocity Doppler Spectroscopy Joseph P. Glaser Cleveland State University Follow this and additional works at: https://engagedscholarship.csuohio.edu/tdr Part of the Astrophysics and Astronomy Commons How does access to this work benefit ou?y Let us know! Recommended Citation Glaser, Joseph P.. "On the Detection of Exoplanets via Radial Velocity Doppler Spectroscopy." The Downtown Review. Vol. 1. Iss. 1 (2015) . Available at: https://engagedscholarship.csuohio.edu/tdr/vol1/iss1/6 This Article is brought to you for free and open access by the Student Scholarship at EngagedScholarship@CSU. It has been accepted for inclusion in The Downtown Review by an authorized editor of EngagedScholarship@CSU. For more information, please contact [email protected]. Glaser: Detection of Exoplanets 1 Introduction to Exoplanets For centuries, some of humanity’s greatest minds have pondered over the possibility of other worlds orbiting the uncountable number of stars that exist in the visible universe. The seeds for eventual scientific speculation on the possibility of these "exoplanets" began with the works of a 16th century philosopher, Giordano Bruno. In his modernly celebrated work, On the Infinite Universe & Worlds, Bruno states: "This space we declare to be infinite (...) In it are an infinity of worlds of the same kind as our own." By the time of the European Scientific Revolution, Isaac Newton grew fond of the idea and wrote in his Principia: "If the fixed stars are the centers of similar systems [when compared to the solar system], they will all be constructed according to a similar design and subject to the dominion of One." Due to limitations on observational equipment, the field of exoplanetary systems existed primarily in theory until the late 1980s. -
Astronomy 2008 Index
Astronomy Magazine Article Title Index 10 rising stars of astronomy, 8:60–8:63 1.5 million galaxies revealed, 3:41–3:43 185 million years before the dinosaurs’ demise, did an asteroid nearly end life on Earth?, 4:34–4:39 A Aligned aurorae, 8:27 All about the Veil Nebula, 6:56–6:61 Amateur astronomy’s greatest generation, 8:68–8:71 Amateurs see fireballs from U.S. satellite kill, 7:24 Another Earth, 6:13 Another super-Earth discovered, 9:21 Antares gang, The, 7:18 Antimatter traced, 5:23 Are big-planet systems uncommon?, 10:23 Are super-sized Earths the new frontier?, 11:26–11:31 Are these space rocks from Mercury?, 11:32–11:37 Are we done yet?, 4:14 Are we looking for life in the right places?, 7:28–7:33 Ask the aliens, 3:12 Asteroid sleuths find the dino killer, 1:20 Astro-humiliation, 10:14 Astroimaging over ancient Greece, 12:64–12:69 Astronaut rescue rocket revs up, 11:22 Astronomers spy a giant particle accelerator in the sky, 5:21 Astronomers unearth a star’s death secrets, 10:18 Astronomers witness alien star flip-out, 6:27 Astronomy magazine’s first 35 years, 8:supplement Astronomy’s guide to Go-to telescopes, 10:supplement Auroral storm trigger confirmed, 11:18 B Backstage at Astronomy, 8:76–8:82 Basking in the Sun, 5:16 Biggest planet’s 5 deepest mysteries, The, 1:38–1:43 Binary pulsar test affirms relativity, 10:21 Binocular Telescope snaps first image, 6:21 Black hole sets a record, 2:20 Black holes wind up galaxy arms, 9:19 Brightest starburst galaxy discovered, 12:23 C Calling all space probes, 10:64–10:65 Calling on Cassiopeia, 11:76 Canada to launch new asteroid hunter, 11:19 Canada’s handy robot, 1:24 Cannibal next door, The, 3:38 Capture images of our local star, 4:66–4:67 Cassini confirms Titan lakes, 12:27 Cassini scopes Saturn’s two-toned moon, 1:25 Cassini “tastes” Enceladus’ plumes, 7:26 Cepheus’ fall delights, 10:85 Choose the dome that’s right for you, 5:70–5:71 Clearing the air about seeing vs.