Development and Applications of Proton Transfer Reaction-Mass Spectrometry for Homeland Security: Trace Detection of Explosives
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Molecular Regulation of Plant Monoterpene Biosynthesis in Relation to Fragrance
Molecular Regulation of Plant Monoterpene Biosynthesis In Relation To Fragrance Mazen K. El Tamer Promotor: Prof. Dr. A.G.J Voragen, hoogleraar in de Levensmiddelenchemie, Wageningen Universiteit Co-promotoren: Dr. ir. H.J Bouwmeester, senior onderzoeker, Business Unit Celcybernetica, Plant Research International Dr. ir. J.P Roozen, departement Agrotechnologie en Voedingswetenschappen, Wageningen Universiteit Promotiecommissie: Dr. M.C.R Franssen, Wageningen Universiteit Prof. Dr. J.H.A Kroeze, Wageningen Universiteit Prof. Dr. A.J van Tunen, Swammerdam Institute for Life Sciences, Universiteit van Amsterdam. Prof. Dr. R.G.F Visser, Wageningen Universiteit Mazen K. El Tamer Molecular Regulation Of Plant Monoterpene Biosynthesis In Relation To Fragrance Proefschrift ter verkrijging van de graad van doctor op gezag van de rector magnificus van Wageningen Universiteit, Prof. dr. ir. L. Speelman, in het openbaar te verdedigen op woensdag 27 november 2002 des namiddags te vier uur in de Aula Mazen K. El Tamer Molecular Regulation Of Plant Monoterpene Biosynthesis In Relation To Fragrance Proefschrift Wageningen Universiteit ISBN 90-5808-752-2 Cover and Invitation Design: Zeina K. El Tamer This thesis is dedicated to my Family & Friends Contents Abbreviations Chapter 1 General introduction and scope of the thesis 1 Chapter 2 Monoterpene biosynthesis in lemon (Citrus limon) cDNA isolation 21 and functional analysis of four monoterpene synthases Chapter 3 Domain swapping of Citrus limon monoterpene synthases: Impact 57 on enzymatic activity and -
Buffer Gas Experiments in Mercury (Hg+) Ion Clock
Buffer Gas Experiments in Mercury (Hg+) Ion Clock Sang K. Chung, John D. Prestage, Robert L. Tjoelker, Lute Maleki California Institute of Technology, Jet Propulsion Laboratory 4800 Oak Grove Drive, Bldg 298 Pasadena, CA 91109 Abstract—We report measured buffer gas collision shifts of the environment and stable helium pressure this system is not 40.507347996xx GHz mercury ion clock transition using inert sufficient to meet mass, power, size, and operability helium, neon, and argon gases and getterable molecular considerations of a space clock [6]. hydrogen and nitrogen gases. The frequency shift due to Two buffer gas / vacuum pump combination are currently methane was also examined. At low partial pressures methane being considered for possible operation of a small space-born gas did not impact the trapped ion number but was observed to strongly relax the population difference in the two hyperfine clock. One approach uses a small getter pump with a fixed clock states thereby reducing the clock resonance signal. A amount of inert buffer gas. Two issues that must be similar population relaxation was also observed for other understood are the long term buffer gas pressure stability and molecular buffer gases (N2, H2) but at much reduced rate. possible evolution of non-getterable gas that could potentially adversely affect clock stability or operation. A second approach is to use a miniature ion pump and a calibrated I. INTRODUCTION micro-leak buffer gas that is not inert (inert gas can shorten In recent years, mercury ion (199Hg+) clock technology has ion pump life very quickly). demonstrated excellent inherent stability, reaching ~3 x 10-16 long-term frequency stability with continuous, free running II. -
And Their OH Reactivity in Various Agro-Ecosystems Sandy Bsaibes
Characterization of biogenic volatile organic compounds (BVOCs) and their OH reactivity in various agro-ecosystems Sandy Bsaibes To cite this version: Sandy Bsaibes. Characterization of biogenic volatile organic compounds (BVOCs) and their OH reactivity in various agro-ecosystems. Global Changes. Université Paris-Saclay, 2019. English. NNT : 2019SACLV093. tel-02614381 HAL Id: tel-02614381 https://tel.archives-ouvertes.fr/tel-02614381 Submitted on 20 May 2020 HAL is a multi-disciplinary open access L’archive ouverte pluridisciplinaire HAL, est archive for the deposit and dissemination of sci- destinée au dépôt et à la diffusion de documents entific research documents, whether they are pub- scientifiques de niveau recherche, publiés ou non, lished or not. The documents may come from émanant des établissements d’enseignement et de teaching and research institutions in France or recherche français ou étrangers, des laboratoires abroad, or from public or private research centers. publics ou privés. Characterization of biogenic volatile organic compounds and their OH reactivity in various : 2019SACLV093 agro-ecosystems NNT Thèse de doctorat de l’Université Paris-Saclay Préparée à l’Université de Versailles Saint-Quentin-en-Yvelines Ecole doctorale n°129 Sciences de l’Environnement d’île-de-France (SEIF) Spécialité de doctorat : chimie atmosphérique Thèse présentée et soutenue à Gif-sur-Yvette, le 12 Décembre 2019 par Sandy Bsaibes Composition du Jury : Didier Hauglustaine Directeur de Recherche, LSCE, CNRS Président Agnès Borbon Chargée de Recherche, LaMP, CNRS Rapporteur Jonathan Williams Senior Scientist, MPIC Rapporteur Corinne Jambert Maître de conférences, LA Examinateur Benjamin Loubet Directeur de Recherche, Ecosys, INRA Examinateur Valérie Gros Directeur de Recherche, LSCE, CNRS Directeur de thèse Contents Acknowledgements .............................................................................................................................. -
Hinokitiol Production in Suspension Cells of Thujopsis Dolabrata Var
55 Original Papers Plant Tissue Culture Letters, 12(1), 55-61(1995) Hinokitiol Production in Suspension Cells of Thujopsis dolabrata var. hondai Makino Ryo FUJII, Kazuo OZAKI, Migifumi INO and Hitoshi WATANABE Integrated Technology Laboratories, Takeda Chemical Industries, Ltd. 11, Ichijoji-takenouchi-cho, Sakyo-ku, Kyoto 606 Japan (Received May 19, 1994) (Accepted October 8, 1994) Suspension cells of Thujopsis dolabrata var. hondai Makino were used as the material for studying the culture conditions by a two-step culture method (cell growth step and secondary metabolite production step) for the production of hinokitiol (Q-thujaplicin). Murashige and Skoog's (MS) medium containing N03-N and NH4-N in the ratio 3-5:1 (total nitrogen 30-75 mM) with 1.0mg/l NAA and 0.2mg/l TDZ was most desirable for cell growth (MS-O medium). The growth showed 14-fold increase after 30 days of culture in this medium. A higher ratio of NH4-N to total nitrogen resulted in hinokitiol accumulation in the cells. When the cells were transferred to the modified MS-O medium with the ratio of N03-N:NH4-N changed to 1:2 (MS-PC medium), an increase of hinokitiol level was observed. Also feeding acetates to the medium enhanced hinokitiol accumula- tion considerably. The highest hinokitiol content of 422tg/g FW was obtained when the cells were cultured in MS-O medium supplemented with 4.3mM acetic acid. Introduction An irregular monoterpene hinokitiol (B-thujaplicin) is widely present in the heartwood of the families Cupressaceae1). Hinokitiol has antimicrobial properties, and recently it has been indicated that hinokitiol suppresses ethylene synthesis and respiration of some fruits and vegetables. -
Comparison of Biogenic Volatile Organic Compound Emissions from Broad Leaved and Coniferous Trees in Turkey
Environmental Impact II 647 Comparison of biogenic volatile organic compound emissions from broad leaved and coniferous trees in Turkey Y. M. Aydin1, B. Yaman1, H. Koca1, H. Altiok1, Y. Dumanoglu1, M. Kara1, A. Bayram1, D. Tolunay2, M. Odabasi1 & T. Elbir1 1Department of Environmental Engineering, Faculty of Engineering, Dokuz Eylul University, Turkey 2Department of Soil Science and Ecology, Faculty of Forestry, Istanbul University, Turkey Abstract Biogenic volatile organic compound (BVOC) emissions from thirty-eight tree species (twenty broad leaved and eighteen coniferous) grown in Turkey were measured. BVOC samples were collected with a specialized dynamic enclosure technique in forest areas where these tree species are naturally grown. In this method, the branches were enclosed in transparent nalofan bags maintaining their natural conditions and avoiding any source of stress. The air samples from the inlet and outlet of the bags were collected on an adsorbent tube containing Tenax. Samples were analyzed using a thermal desorption (TD) and gas chromatography mass spectrometry (GC/MS) system. Sixty-five BVOC compounds were analyzed in five major groups: isoprene, monoterpenes, sesquiterpens, oxygenated sesquiterpenes and other oxygenated VOCs. Emission factors were calculated and adjusted to standard conditions (1000 μmol/m2 s photosynthetically active radiation-PAR and 30°C temperature). Consistent with the literature, broad leaved trees emitted mainly isoprene while the coniferous trees emitted mainly monoterpenes. Even though fir species are coniferous trees, they emitted significant amounts of isoprene in addition to monoterpenes. Oak species showed a large inter-species variability in their emissions. Pine species emitted mainly monoterpenes and substantial amounts of oxygenated compounds. Keywords: BVOC emissions, dynamic enclosure system, emission factor, Turkey. -
Determination of Terpenoid Content in Pine by Organic Solvent Extraction and Fast-Gc Analysis
ORIGINAL RESEARCH published: 25 January 2016 doi: 10.3389/fenrg.2016.00002 Determination of Terpenoid Content in Pine by Organic Solvent Extraction and Fast-GC Analysis Anne E. Harman-Ware1* , Robert Sykes1 , Gary F. Peter2 and Mark Davis1 1 National Bioenergy Center, National Renewable Energy Laboratory, Golden, CO, USA, 2 School of Forest Resources and Conservation, University of Florida, Gainesville, FL, USA Terpenoids, naturally occurring compounds derived from isoprene units present in pine oleoresin, are a valuable source of chemicals used in solvents, fragrances, flavors, and have shown potential use as a biofuel. This paper describes a method to extract and analyze the terpenoids present in loblolly pine saplings and pine lighter wood. Various extraction solvents were tested over different times and temperatures. Samples were analyzed by pyrolysis-molecular beam mass spectrometry before and after extractions to monitor the extraction efficiency. The pyrolysis studies indicated that the optimal extraction method used a 1:1 hexane/acetone solvent system at 22°C for 1 h. Extracts from the hexane/acetone experiments were analyzed using a low thermal mass modular accelerated column heater for fast-GC/FID analysis. The most abundant terpenoids from Edited by: the pine samples were quantified, using standard curves, and included the monoter- Subba Rao Chaganti, University of Windsor, Canada penes, α- and β-pinene, camphene, and δ-carene. Sesquiterpenes analyzed included Reviewed by: caryophyllene, humulene, and α-bisabolene. Diterpenoid resin acids were quantified in Yu-Shen Cheng, derivatized extractions, including pimaric, isopimaric, levopimaric, palustric, dehydroabi- National Yunlin University of Science and Technology, Taiwan etic, abietic, and neoabietic acids. -
Enhanced Escape Rate for Hg 254Nm Resonance Radiation in Fluorescent Lamps
Home Search Collections Journals About Contact us My IOPscience Enhanced escape rate for Hg 254 nm resonance radiation in fluorescent lamps This content has been downloaded from IOPscience. Please scroll down to see the full text. 2013 J. Phys. D: Appl. Phys. 46 415204 (http://iopscience.iop.org/0022-3727/46/41/415204) View the table of contents for this issue, or go to the journal homepage for more Download details: IP Address: 128.104.46.196 This content was downloaded on 24/09/2013 at 02:20 Please note that terms and conditions apply. IOP PUBLISHING JOURNAL OF PHYSICS D: APPLIED PHYSICS J. Phys. D: Appl. Phys. 46 (2013) 415204 (8pp) doi:10.1088/0022-3727/46/41/415204 Enhanced escape rate for Hg 254 nm resonance radiation in fluorescent lamps James E Lawler1 and Mark G Raizen2 1 Department of Physics, University of Wisconsin, Madison, WI 53706, USA 2 Center for Nonlinear Dynamics and Department of Physics, University of Texas, Austin, TX 78712, USA Received 7 June 2013, in final form 7 August 2013 Published 23 September 2013 Online at stacks.iop.org/JPhysD/46/415204 Abstract The potential of the low-cost MAGIS isotopic separation method to improve fluorescent lamp efficacy is explored using resonance radiation transport simulations. New Hg isotopic mixes are discovered that yield escape rates for 254 nm Hg I resonance radiation equal to 117% to 122% of the rate for a natural isotopic mix under the same lamp conditions. (Some figures may appear in colour only in the online journal) 1. Introduction will represent over 75% of all lighting sales by 2030, resulting in an annual primary energy savings of 3.4 quads.’ Fluorescent lighting is the technology of choice for almost Even after inorganic LED and/or organic LED (OLED) all non-residential indoor lighting applications around the technology achieve competitive performance and cost levels, world. -
An IMS-IMS Analogue of MS-MS
Anal. Chem. 2006, 78, 4161-4174 An IMS-IMS Analogue of MS-MS Stormy L. Koeniger,² Samuel I. Merenbloom,² Stephen J. Valentine,³ Martin F. Jarrold,² Harold R. Udseth,§ Richard D. Smith,§ and David E. Clemmer*,² Department of Chemistry, Indiana University, Bloomington, Indiana 47405, Predictive Physiology and Medicine (PPM), 1424 West Adams Hill, Bloomington, Indiana 47403, and Environmental Molecular Sciences Laboratory, Pacific Northwest National Laboratory, P.O. Box 999, Richland, Washington 99352 The development of a new ion mobility/mass spectrometry nature of the IMS measurement and soft ionization methods instrument that incorporates a multifield drift tube/ion amendable to biopolymers,9-11 has led to the development of a funnel design is described. In this instrument, individual number of IMS-based instruments. For example, several groups components from a mixture of ions can be resolved and have now coupled IMS instruments to mass spectrometers1a,12 (MS selected on the basis of mobility differences prior to and MS-MS) and liquid chromatography (LC) instruments13 to collisional activation inside the drift tube. The fragment characterize complex biological mixtures.14-17 ions that are produced can be dispersed again in a second Although significant effort to incorporate IMS with other ion mobility spectrometry (IMS) region prior to additional methods to provide a multidimensional separation has been made, collisional activation and MS analysis. The result is an little work has been done to develop a multidimensional IMS IMS-IMS analogue of MS-MS. Here, we describe the separation. Several years ago, our group developed a simple split- preliminary instrumental design and experimental ap- (8) See, for example: Jarrold, M. -
Tungsten Electrode with Emitter
US 20060O87242A1 (19) United States (12) Patent Application Publication (10) Pub. No.: US 2006/0087242 A1 Scholl et al. (43) Pub. Date: Apr. 27, 2006 (54) LOW-PRESSURE GAS DISCHARGE LAMP Publication Classification WITH ELECTRON EMITTER SUBSTANCES SMILAR TO BATO3 (51) Int. Cl. HOI. I7/04 (2006.01) (76) Inventors: Robert Peter Scholl, Roetgen (DE); HOI. 6L/04 (2006.01) Rainer Hilbig, Aachen (DE); Bernd (52) U.S. Cl. ..................... 313/633; 313/311; 313/346 R Rausenberger, Aachen (DE) Correspondence Address: (57) ABSTRACT PHILIPS INTELLECTUAL PROPERTY & A low-pressure gas discharge lamp is described, which is STANDARDS equipped with a gas-discharge vessel containing an inert gas P.O. BOX 3 OO1 filling as the buffer gas and an indium, thallium and/or BRIARCLIFF MANOR, NY 10510 (US) copper halide, and with electrodes and with means for Appl. No.: 10/526,923 generating and maintaining a low-pressure gas discharge, (21) which has as the electron emitter Substance a compound (22) PCT Fed: Aug. 29, 2003 selected from the group of ABO or ABO, ACOs, or ADO, wherein: A=an alkaline earth element or a mix (86) PCT No.: PCT/BO3/O3948 ture of several different alkaline earth elements, B=cerium, titanium, Zirconium, hafnium, or a mixture of these ele (30) Foreign Application Priority Data ments, C=vanadium, niobium, tantalum, or a mixture of these elements, D=Scandium, yttrium, lanthanum, a rare Sep. 12, 2002 (DE)..................................... 102-42-241.9 earth element, or a mixture of these elements. tungsten electrode With emitter discharge chamber with InBr Or similar Substances Patent Application Publication Apr. -
Energy Transfer Processes in Electron Beam Excited Mixtures of Laser Dye Vapors with Rare Gases G
Energy transfer processes in electron beam excited mixtures of laser dye vapors with rare gases G. Marowsky Max-Planck Institut fur Biophysikalische Chemie. D 3400 Gottingen. Federal Republic of Germany R. Cordray, F. Tittel, and B. Wilson Electrical Engineering Department, Rice University. Houston. Texas 77001 J. W. Keto Physics Department. University of Texas at Austin. Austin. Texas 78712 (Received 26 May 1977) The energy transfer mechanisms for electron beam excited N -92 dye vapor in various bU!fer gas mixtur.es have been examined. Optimum conditions for achieving intense dye vapor fluorescence with short duratIOn electron pulse excitation are reported. INTRODUCTION colliSional excitation from the metastable states of the Direct electrical excitation of dye vapor lasers has rare gas buffer atoms and molecules and electron im pact excitation appear to be the dominant processes for received considerable attention in recent years. l,Z Elec trical excitation offers the possibilities of overcoming coupling electron beam energy to the dye vapor. By op timizing the buffer gas composition, the total pressure, the inherent limitations in efficiency for optically pumped dye lasers, extending the present uv wavelength limit and the electron beam deposition it is possible to en hance the fluorescence yields of excited state populations of about 320 nm to shorter wavelengths, and scaling to of buffer gas-dye vapor mixtures. Due to the complex high power laser systems. In this paper we report re ity of these mixtures under high levels of eXCitation, no sults of a study to identify the optimum energy transfer quantitative measurements on kinetic parameters such conditions which produce efficient fluorescence yields as relevant rate constants and colliSional and radiative for electron beam excited high pressure buffer gas-dye lifetimes have been obtained as yet. -
APPLICATION NOTE LD20-05 Multidetek2 Gas Chromatograph with Plasmadetek2 & TCD Detectors Uses for the Analysis of Purity Xenon-Krypton-Neon
APPLICATION NOTE LD20-05 MultiDetek2 gas chromatograph with PlasmaDetek2 & TCD detectors uses for the analysis of purity Xenon-Krypton-Neon MultiDetek2 PlasmaDetek2 The noble gases also called inert gases or rare gases have several characteristics that make them important and unique as: low reactivity, low thermal conductivity and high stability, among others. Being at very low concentration in the earth’s atmosphere, it makes these gases very expensive to produce. The six naturally noble gases are Helium (He), Neon (Ne), Argon (Ar), Krypton (Kr), Xenon (Xe) and the radioactive Radon (Rn). The rarest gases of these are Xenon, Krypton and Neon making them very expensive to use for industrial applications. NEON/KRYPTON/XENON MAJOR APPLICATIONS: Aerospace: Xenon is used for the following aerospace applications: satellite programs, space travel, propulsion agent for spacecraft, satellite thruster and interplanetary probe. Electronics: These rare gases, can be used in many electronics applications such as: excimer lasers, buffer gas used in lasers for semiconductor manufacturing, deep trench etching of DRAM integrated circuits, focused etch process, and plasma panel display. Glass: Krypton is used as a filler in the production of double and triple-pane insulated windows. Major advantages of using krypton are reducing heat loss, increasing heat transfer resistance in the unit, and reducing levels of solar radiation. You can also increase the R-value or decrease the U-factor for window and door insulation with krypton, xenon and rare gas mixtures. Lasers: Neon-based excimer lasers are utilized for etching silicon wafers, LASIK eye surgery, micro-machining organic materials, UV lithography in integrated circuit fabrication, micro drilling, He/Ne mixes for optical readers, and wafer dicing. -
"The Buffer-Gas Positron Accumulator and Resonances in Positron
Written in conjunction with the symposium honoring the retirement of Dick Drachman and Aaron Temkin (NASA Goddard Space Flight Center, Greenbelt, MD; November 18, 2005); to be published by the NASA Conference Publication Service, A. Bhatia, ed. (2006). THE BUFFER-GAS POSITRON ACCUMULATOR AND RESONANCES IN POSITRON-MOLECULE INTERACTIONS C. M. Surko Department of Physics, University of California, San Diego, La Jolla CA 92093 ABSTRACT This is a personal account of the development of our buffer-gas positron trap and the new generation of cold beams that these traps enabled. Dick Drachman provided much appreciated advice to us from the time we started the project. The physics underlying trap operation is related to resonances (or apparent resonances) in positron- molecule interactions. Amusingly, experiments enabled by the trap allowed us to understand these processes. The positron-resonance “box score” to date is one resounding “yes,” namely vibrational Feshbach resonances in positron annihilation on hydrocarbons; a “probably” for positron-impact electronic excitation of CO and N2; and a “maybe” for vibrational excitation of selected molecules. Two of these processes enabled the efficient operation of the trap, and one almost killed it in infancy. We conclude with a brief overview of further applications of the trapping technology discussed here, such as “massive” positron storage and beams with meV energy resolution. IT ALL STARTED AT LUNCH WITH MARV Since this paper is written in conjunction with the symposium marking the retirement of Dick Drachman and Aaron Temkin, I depart from third-person style to relate a personal view of the development of the buffer-gas trap and the physics that has come from it.