Noble Gas Discharges

Total Page:16

File Type:pdf, Size:1020Kb

Noble Gas Discharges NOBLE GAS DISCHARGES Raphael Mehlich 21.Juni.2010 IdIndex History of noble gases Properties of noble gases High pressure discharge lamps Glow lamps Noble gas excimer Raphael Mehlich 21.Juni.2010 His tory of noble gases 1868: Jules Janssen and Norman Lockler discov ered Helium 1892: Luigi Palmieri verified Helium 1894: LdLord RlihRayleigh has discovere d Argon 1898: Lord Rayleigh and Morris William Travers verified Neon, Xenon and KtKrypton by ftilfractional dis tilla tion of air 1900: Friedrich Ernst Dorn discovered Radon 2006: UnunoctUiium was made byb theInstIiitute for NucNllear Research and the Lawrence Livermore National Laboratory Raphael Mehlich 21.Juni.2010 PtiProperties of noble gases All noble gases are odorless, colorless, nontoxic, incombustible under normal conditions and are stable in a non‐molecular state Raphael Mehlich 21.Juni.2010 Hig h Pressure Disc harge Lamps • Pressure of noble (Xe) gas 5‐20 bar during operation 12‐100 bar • Ignition voltage 20‐30 kV operating voltage 30 V • Distance of electrodes 0,2mm to several mm • Quantum efficiency 40 lm/Watt • Comparable to solar spectrum color temperature ~ 6000 K Raphael Mehlich 21.Juni.2010 AlitiApplication for Disc harge Lamp • Vis‐Spectroscopy (400‐800 nm) • Projector • Spotlight • Purification of water • Pros: ‐ bright light ‐ homogeneous spectrum (400‐800nm) • Cons: ‐ formation of ozone ‐ short lifetime (several 1000h) ‐ high technical effort ‐ safety requirement Raphael Mehlich 21.Juni.2010 Glow Disc harge Lamps • Pressure of noble gas (Xe) less than 10‐2mbar • Operating voltage < 100V • Color depends on applied noble gas • Cold bulb Raphael Mehlich 21.Juni.2010 AlitiApplications • Adv ertisement • Phase checker • Pros: ‐ cold bulb ‐ pure color s Raphael Mehlich 21.Juni.2010 EiExcimers • Excimer = excited dimers • Dimer: two noble gas atoms (Xe2*,Ar2*,…) or noble gas halides (XeF*,KrCl*) • EEixcimer are only stable in exciidted state • R* + R R2* R+ + X‐ + M RX* + M R* + X2 RX* + X Raphael Mehlich 21.Juni.2010 AlitiApplications of EiExcimer Disc harges Light Screens (Planon® ) Excimer Laser High power Cold UV Excimer System Planon® Raphael Mehlich 21.Juni.2010 Plasma TV Noble gases Xe for 148 and 172 nm Ne for orange range Excitation of Xe atoms by electron collision UV Radiation is converted by phosphor into visible light Raphael Mehlich 21.Juni.2010 Sources Hans‐Jörg Bullinger – Technologieführer, Springer Verlag, Berlin (2007) Dieter Meschede – Gerthsen Physik, Springer Verlag, Berlin (2006) Erwin Riedel –AnorganischeChemie, Walter de Gruyter Verlag, Berlin (2004) Wolfgang Demtröder – Experimentalphysik 3, Springer Verlag, Berlin (2010) Joachim Staab ‐ Industriele Gasanalyse, Oldenbourg Verlag, München (1994) http://www. elektronikinfo.de/strom/thermischelampen .htm http://www.uni‐muenster.de/Physik.TD/gasentladungslampen.html http://www.heraeus‐noblelight.com http://www.newport.com http://www.uni‐protokolle.de Raphael Mehlich 21.Juni.2010.
Recommended publications
  • Protein Shape Modulates Crowding Effects
    Protein shape modulates crowding effects Alex J. Gusemana, Gerardo M. Perez Goncalvesa, Shannon L. Speera, Gregory B. Youngb, and Gary J. Pielaka,b,c,d,1 aDepartment of Chemistry, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599; bDepartment of Biochemistry & Biophysics, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599; cLineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599; and dIntegrative Program for Biological and Genome Sciences, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599 Edited by Susan Marqusee, University of California, Berkeley, CA, and approved September 12, 2018 (received for review June 18, 2018) Protein−protein interactions are usually studied in dilute buffered mildly influenced by hard-core repulsions. Berg also predicted solutions with macromolecule concentrations of <10 g/L. In cells, that more-compact dimers are more likely to be stabilized by however, the macromolecule concentration can exceed 300 g/L, hard-core repulsions. Here, we test this idea by changing the resulting in nonspecific interactions between macromolecules. shape of a dimer in a controlled fashion. These interactions can be divided into hard-core steric repulsions Scaled particle theory is based on statistical mechanics. For and “soft” chemical interactions. Here, we test a hypothesis from situations like those investigated here, the theory considers so- scaled particle theory; the influence of hard-core repulsions on a lution nonideality as arising from the presence of cosolutes (13– protein dimer depends on its shape. We tested the idea using a 15). As often applied, the solvent and cosolutes are considered side-by-side dumbbell-shaped dimer and a domain-swapped ellip- hard spheres, which leads to three consequences: Molecules only soidal dimer.
    [Show full text]
  • Midterm Examination #3, December 11, 2015 1. (10 Point
    NAME: NITROMETHANE CHEMISTRY 443, Fall, 2015(15F) Section Number: 10 Midterm Examination #3, December 11, 2015 Answer each question in the space provided; use back of page if extra space is needed. Answer questions so the grader can READILY understand your work; only work on the exam sheet will be considered. Write answers, where appropriate, with reasonable numbers of significant figures. You may use only the "Student Handbook," a calculator, and a straight edge. 1. (10 points) Argon is a noble gas. For all practical purposes it can be considered an ideal gas. DO NOT WRITE Calculate the change in molar entropy of argon when it is subjected to a process in which the molar IN THIS SPACE volume is tripled and the temperature is simultaneously changed from 300 K to 400 K. 1,2 _______/25 This is a straightforward application of thermodynamics: 3,4 _______/25 = = + = + 2 2 2 2 5 _______/20 Identifying ∆the derivative� and� doing1 � the� integrals � 1give� � �1 � � �1 3 3 400 6,7 _______/20 = + = 8.3144349 + 8.3144349 2 2 1 2 300 8 _______/10 where the∆ heat capacity � 1� at constant � 1volume� of a monatomic �ideal� gas is� . � � � 3 ============= = 9.13434 + 3.58786 = 12.722202 9 _______/5 ∆ (Extra credit) ============= TOTAL PTS 2. (15 points) Benzene ( • = 96.4 ) and toluene ( • = 28.9 ) form a nearly ideal solution over a wide range. For purposes of this question, you may assume that a solution of the two is ideal. (a) What is the total vapor pressure above a solution containing 5.00 moles of benzene and 3.25 moles of toluene? 5.00 3.25 = • + • = (96.4 ) + (28.9 ) 5.00 + 3.25 5.00 + 3.25 = 58.4 + 11.4 = 69.8 (b) What is mole fraction of benzene in the vapor above this solution? .
    [Show full text]
  • The Oganesson Odyssey Kit Chapman Explores the Voyage to the Discovery of Element 118, the Pioneer Chemist It Is Named After, and False Claims Made Along the Way
    in your element The oganesson odyssey Kit Chapman explores the voyage to the discovery of element 118, the pioneer chemist it is named after, and false claims made along the way. aving an element named after you Ninov had been dismissed from Berkeley for is incredibly rare. In fact, to be scientific misconduct in May5, and had filed Hhonoured in this manner during a grievance procedure6. your lifetime has only happened to Today, the discovery of the last element two scientists — Glenn Seaborg and of the periodic table as we know it is Yuri Oganessian. Yet, on meeting Oganessian undisputed, but its structure and properties it seems fitting. A colleague of his once remain a mystery. No chemistry has been told me that when he first arrived in the performed on this radioactive giant: 294Og halls of Oganessian’s programme at the has a half-life of less than a millisecond Joint Institute for Nuclear Research (JINR) before it succumbs to α -decay. in Dubna, Russia, it was unlike anything Theoretical models however suggest it he’d ever experienced. Forget the 2,000 ton may not conform to the periodic trends. As magnets, the beam lines and the brand new a noble gas, you would expect oganesson cyclotron being installed designed to hunt to have closed valence shells, ending with for elements 119 and 120, the difference a filled 7s27p6 configuration. But in 2017, a was Oganessian: “When you come to work US–New Zealand collaboration predicted for Yuri, it’s not like a lab,” he explained. that isn’t the case7.
    [Show full text]
  • Dimerization of Carboxylic Acids: an Equation of State Approach
    Downloaded from orbit.dtu.dk on: Oct 05, 2021 Dimerization of Carboxylic Acids: An Equation of State Approach Tsivintzelis, Ioannis; Kontogeorgis, Georgios; Panayiotou, Costas Published in: Journal of Physical Chemistry Part B: Condensed Matter, Materials, Surfaces, Interfaces & Biophysical Link to article, DOI: 10.1021/acs.jpcb.6b10652 Publication date: 2017 Document Version Peer reviewed version Link back to DTU Orbit Citation (APA): Tsivintzelis, I., Kontogeorgis, G., & Panayiotou, C. (2017). Dimerization of Carboxylic Acids: An Equation of State Approach. Journal of Physical Chemistry Part B: Condensed Matter, Materials, Surfaces, Interfaces & Biophysical, 121(9), 2153-2163. https://doi.org/10.1021/acs.jpcb.6b10652 General rights Copyright and moral rights for the publications made accessible in the public portal are retained by the authors and/or other copyright owners and it is a condition of accessing publications that users recognise and abide by the legal requirements associated with these rights. Users may download and print one copy of any publication from the public portal for the purpose of private study or research. You may not further distribute the material or use it for any profit-making activity or commercial gain You may freely distribute the URL identifying the publication in the public portal If you believe that this document breaches copyright please contact us providing details, and we will remove access to the work immediately and investigate your claim. On the Dimerization of Carboxylic Acids: An Equation of State Approach Ioannis Tsivintzelis*,1, Georgios M. Kontogeorgis2 and Costas Panayiotou1 1Department of Chemical Engineering, Aristotle University of Thessaloniki, 54124 Thessaloniki, Greece. 2Center for Energy Resources Engineering (CERE), Department of Chemical and Biochemical Engineering, Technical University of Denmark, DK-2800 Kgs.
    [Show full text]
  • Spin Delocalization, Polarization, and London Dispersion Forces Govern the Formation of Diradical Pimers
    Chemistry Publications Chemistry 2-22-2020 Spin Delocalization, Polarization, and London Dispersion Forces Govern the Formation of Diradical Pimers Joshua P. Peterson Iowa State University, [email protected] Arkady Ellern Iowa State University, [email protected] Arthur H. Winter Iowa State University, [email protected] Follow this and additional works at: https://lib.dr.iastate.edu/chem_pubs Part of the Chemistry Commons The complete bibliographic information for this item can be found at https://lib.dr.iastate.edu/ chem_pubs/1215. For information on how to cite this item, please visit http://lib.dr.iastate.edu/ howtocite.html. This Article is brought to you for free and open access by the Chemistry at Iowa State University Digital Repository. It has been accepted for inclusion in Chemistry Publications by an authorized administrator of Iowa State University Digital Repository. For more information, please contact [email protected]. Spin Delocalization, Polarization, and London Dispersion Forces Govern the Formation of Diradical Pimers Abstract Some free radicals are stable enough to be isolated, but most are either unstable transient species or exist as metastable species in equilibrium with a dimeric form, usually a spin-paired sigma dimer or a pi dimer (pimer). To gain insight into the different modes of dimerization, we synthesized and evaluated a library of 15 aryl dicyanomethyl radicals in order to probe what structural and molecular parameters lead to σ- versus π-dimerization. We evaluated the divergent dimerization behavior by measuring the strength of each radical association by variable-temperature electron paramagnetic resonance spectroscopy, determining the mode of dimerization (σ- or π-dimer) by UV–vis spectroscopy and X-ray crystallography, and performing computational analysis.
    [Show full text]
  • Polymorphism, Halogen Bonding, and Chalcogen Bonding in the Diiodine Adducts of 1,3- and 1,4-Dithiane
    molecules Article Polymorphism, Halogen Bonding, and Chalcogen Bonding in the Diiodine Adducts of 1,3- and 1,4-Dithiane Andrew J. Peloquin 1, Srikar Alapati 2, Colin D. McMillen 1, Timothy W. Hanks 2 and William T. Pennington 1,* 1 Department of Chemistry, Clemson University, Clemson, SC 29634, USA; [email protected] (A.J.P.); [email protected] (C.D.M.) 2 Department of Chemistry, Furman University, Greenville, SC 29613, USA; [email protected] (S.A.); [email protected] (T.W.H.) * Correspondence: [email protected] Abstract: Through variations in reaction solvent and stoichiometry, a series of S-diiodine adducts of 1,3- and 1,4-dithiane were isolated by direct reaction of the dithianes with molecular diiodine in solution. In the case of 1,3-dithiane, variations in reaction solvent yielded both the equatorial and the axial isomers of S-diiodo-1,3-dithiane, and their solution thermodynamics were further studied via DFT. Additionally, S,S’-bis(diiodo)-1,3-dithiane was also isolated. The 1:1 cocrystal, (1,4-dithiane)·(I2) was further isolated, as well as a new polymorph of S,S’-bis(diiodo)-1,4-dithiane. Each structure showed significant S···I halogen and chalcogen bonding interactions. Further, the product of the diiodine-promoted oxidative addition of acetone to 1,4-dithiane, as well as two new cocrystals of 1,4-dithiane-1,4-dioxide involving hydronium, bromide, and tribromide ions, was isolated. Keywords: crystal engineering; chalcogen bonding; halogen bonding; polymorphism; X-ray diffraction Citation: Peloquin, A.J.; Alapati, S.; McMillen, C.D.; Hanks, T.W.; Pennington, W.T.
    [Show full text]
  • Understanding the Kinetics of the Clo Dimer Cycle
    Atmos. Chem. Phys., 7, 3055–3069, 2007 www.atmos-chem-phys.net/7/3055/2007/ Atmospheric © Author(s) 2007. This work is licensed Chemistry under a Creative Commons License. and Physics Understanding the kinetics of the ClO dimer cycle M. von Hobe1, R. J. Salawitch2, T. Canty2, H. Keller-Rudek3, G. K. Moortgat3, J.-U. Grooß1, R. Muller¨ 1, and F. Stroh1 1Forschungszentrum Julich¨ GmbH, Institute for Chemistry and Dynamics of the Geosphere (ICG-1), Julich,¨ Germany 2Jet Propulsion Laboratory, California Institute of Technology, Pasadena, California, USA 3Max-Planck-Institute for Chemistry, Atmospheric Chemistry Division, Mainz, Germany Received: 12 June 2006 – Published in Atmos. Chem. Phys. Discuss.: 14 August 2006 Revised: 17 October 2006 – Accepted: 22 May 2007 – Published: 15 June 2007 Abstract. Among the major factors controlling ozone loss in 1 Introduction the polar vortices in winter/spring is the kinetics of the ClO dimer catalytic cycle. Here, we propose a strategy to test and The ClO dimer cycle is one of the most important catalytic improve our understanding of these kinetics by comparing cycles destroying ozone in the polar vortices in late win- and combining information on the thermal equilibrium be- ter/early spring (Molina and Molina, 1987): tween ClO and Cl2O2, the rate of Cl2O2 formation, and the krec Cl O photolysis rate from laboratory experiments, theoret- −→ 2 2 ClO + ClO + M Cl O + M (R1) ical studies and field observations. Concordant with a num- ←− 2 2 k ber of earlier studies, we find considerable inconsistencies of diss some recent laboratory results with rate theory calculations J Cl2O2 + hν −→ Cl + ClOO (R2) and stratospheric observations of ClO and Cl2O2.
    [Show full text]
  • The Noble Gases
    INTERCHAPTER K The Noble Gases When an electric discharge is passed through a noble gas, light is emitted as electronically excited noble-gas atoms decay to lower energy levels. The tubes contain helium, neon, argon, krypton, and xenon. University Science Books, ©2011. All rights reserved. www.uscibooks.com Title General Chemistry - 4th ed Author McQuarrie/Gallogy Artist George Kelvin Figure # fig. K2 (965) Date 09/02/09 Check if revision Approved K. THE NOBLE GASES K1 2 0 Nitrogen and He Air P Mg(ClO ) NaOH 4 4 2 noble gases 4.002602 1s2 O removal H O removal CO removal 10 0 2 2 2 Ne Figure K.1 A schematic illustration of the removal of O2(g), H2O(g), and CO2(g) from air. First the oxygen is removed by allowing the air to pass over phosphorus, P (s) + 5 O (g) → P O (s). 20.1797 4 2 4 10 2s22p6 The residual air is passed through anhydrous magnesium perchlorate to remove the water vapor, Mg(ClO ) (s) + 6 H O(g) → Mg(ClO ) ∙6 H O(s), and then through sodium hydroxide to remove 18 0 4 2 2 4 2 2 the carbon dioxide, NaOH(s) + CO2(g) → NaHCO3(s). The gas that remains is primarily nitrogen Ar with about 1% noble gases. 39.948 3s23p6 36 0 The Group 18 elements—helium, K-1. The Noble Gases Were Kr neon, argon, krypton, xenon, and Not Discovered until 1893 83.798 radon—are called the noble gases 2 6 4s 4p and are noteworthy for their rela- In 1893, the English physicist Lord Rayleigh noticed 54 0 tive lack of chemical reactivity.
    [Show full text]
  • (100) Surface with Fluorine in Presence of Water – a Density Functional Study
    Int. J. Mol. Sci. 2001, 2, 40-56 International Journal of Molecular Sciences ISSN 1422-0067 © 2001 by MDPI www.mdpi.org/ijms/ Structural And Energetic Changes of Si (100) Surface With Fluorine in Presence of Water – A Density Functional Study Abhijit Chatterjee *, Takashi Iwasaki and Takeo Ebina Inorganic Materials Section, Tohoku National Industrial Research Institute, 4-2-1 Nigatake, Miyagino- ku, Sendai 983-8551, JAPAN. Fax: +81-22-236-6839. Phone: +81-22-237-5211 * Author to whom correspondence should be addressed. Email: [email protected] Received: 16 November 2000 / Accepted: 28 January 2001 / Published: 1 May 2001 Abstract: We report density functional electronic structure calculations to monitor the change in the surface characteristics of the Si (100)-2x1 surface after fluorination followed by interaction with water. Embedded finite silicon clusters are used to model an extended Si (100)-2x1 surface. Two high symmetry pathways and subsequent adsorption sites were examined: (i) adsorption of an fluorine atom directing onto a silicon dangling bond to form a monocoordinated fluorine atom (ii) adsorption of a fluorine atom directing on top of silicon dimer to form a bridging dicoordinated fluorine atom. However, in the later case we find that no barrier exists for the bridging fluorine atom to slide towards silicon dimer dangling bond to form more stable mono coordinated Si-F bond. We calculated activation barriers and equilibrium surface configuration as a function of fluorine coverage upto 2.0 ML. We compared the stability of the fluorinated surface. The results were compared with existing experimental and theoretical results. The reaction of water with HF treated Si surface is monitored.
    [Show full text]
  • The Dimer-Monomer Equilibrium of SARS-Cov-2 Main
    www.nature.com/scientificreports OPEN The dimer‑monomer equilibrium of SARS‑CoV‑2 main protease is afected by small molecule inhibitors Lucia Silvestrini1, Norhan Belhaj2, Lucia Comez3, Yuri Gerelli2, Antonino Lauria4, Valeria Libera5, Paolo Mariani2, Paola Marzullo4, Maria Grazia Ortore2, Antonio Palumbo Piccionello4, Caterina Petrillo5, Lucrezia Savini1, Alessandro Paciaroni5 & Francesco Spinozzi2* The maturation of coronavirus SARS‑CoV‑2, which is the etiological agent at the origin of the COVID‑ 19 pandemic, requires a main protease Mpro to cleave the virus‑encoded polyproteins. Despite a wealth of experimental information already available, there is wide disagreement about the Mpro monomer‑dimer equilibrium dissociation constant. Since the functional unit of Mpro is a homodimer, the detailed knowledge of the thermodynamics of this equilibrium is a key piece of information for possible therapeutic intervention, with small molecules interfering with dimerization being potential broad‑spectrum antiviral drug leads. In the present study, we exploit Small Angle X‑ray Scattering (SAXS) to investigate the structural features of SARS‑CoV‑2 Mpro in solution as a function of protein concentration and temperature. A detailed thermodynamic picture of the monomer‑dimer equilibrium is derived, together with the temperature‑dependent value of the dissociation constant. SAXS is also used to study how the Mpro dissociation process is afected by small inhibitors selected by virtual screening. We fnd that these inhibitors afect dimerization and enzymatic activity to a diferent extent and sometimes in an opposite way, likely due to the diferent molecular mechanisms underlying the two processes. The Mpro residues that emerge as key to optimize both dissociation and enzymatic activity inhibition are discussed.
    [Show full text]
  • Noble Gases in the Earth and Its Atmosphere
    View metadata, citation and similar papers at core.ac.uk brought to you by CORE provided by Missouri University of Science and Technology (Missouri S&T): Scholars' Mine Scholars' Mine Masters Theses Student Theses and Dissertations 1967 Noble gases in the earth and its atmosphere Robert Anthony Canalas Follow this and additional works at: https://scholarsmine.mst.edu/masters_theses Part of the Chemistry Commons Department: Recommended Citation Canalas, Robert Anthony, "Noble gases in the earth and its atmosphere" (1967). Masters Theses. 6875. https://scholarsmine.mst.edu/masters_theses/6875 This thesis is brought to you by Scholars' Mine, a service of the Missouri S&T Library and Learning Resources. This work is protected by U. S. Copyright Law. Unauthorized use including reproduction for redistribution requires the permission of the copyright holder. For more information, please contact [email protected]. NOBLE GASES IN THE EARTH AND ITS ATMOSPHERE BY ROBERT ANTHONY CANAIAS _ ,qtj6 - A 129523 THESIS submitted to the faculty of the UNIVERSITY OF MISSOURI AT ROLLA in partial fulfillment of the work required for the Degree of MASTER OF SCIENCE IN CHEMISTRY Rolla, Missouri Approved by ii ABSTRACT Abundances of noble gases extracted from Fig Tree Shale exhibit a marked deviation from the gas content of eclogitic rocks purported to be mantle material. The abundances of the heavy noble gases in shale were found to exceed the highest known meteoritic values. The abundances of the lighter noble gases were found to be comparable to the abundances of these gases in typical chondrites. Temperature gradient analyses show that excess heavy gases are released at low temperatures.
    [Show full text]
  • Argon: Systematic Review on Neuro- and Organoprotective Properties of an “Inert” Gas
    Int. J. Mol. Sci. 2014, 15, 18175-18196; doi:10.3390/ijms151018175 OPEN ACCESS International Journal of Molecular Sciences ISSN 1422-0067 www.mdpi.com/journal/ijms Review Argon: Systematic Review on Neuro- and Organoprotective Properties of an “Inert” Gas Anke Höllig 1,2, Anita Schug 1, Astrid V. Fahlenkamp 2, Rolf Rossaint 2, Mark Coburn 2,* and Argon Organo-Protective Network (AON) † 1 Department of Neurosurgery, University RWTH Aachen, 52074 Aachen, Germany; E-Mails: [email protected] (A.H.); [email protected] (A.S.) 2 Department of Anesthesiology, University RWTH Aachen, 52074 Aachen, Germany; E-Mails: [email protected] (A.V.F.); [email protected] (R.R.) † Members are listed in Appendix. * Author to whom correspondence should be addressed; E-Mail: [email protected]; Tel.: +49-241-80-88179; Fax: +49-241-80-82406. External Editor: Katalin Prokai-Tatrai Received: 14 August 2014; in revised form: 12 September 2014 / Accepted: 23 September 2014 / Published: 10 October 2014 Abstract: Argon belongs to the group of noble gases, which are regarded as chemically inert. Astonishingly some of these gases exert biological properties and during the last decades more and more reports demonstrated neuroprotective and organoprotective effects. Recent studies predominately use in vivo or in vitro models for ischemic pathologies to investigate the effect of argon treatment. Promising data has been published concerning pathologies like cerebral ischemia, traumatic brain injury and hypoxic ischemic encephalopathy. However, models applied and administration of the therapeutic gas vary. Here we provide a systematic review to summarize the available data on argon’s neuro- and organoprotective effects and discuss its possible mechanism of action.
    [Show full text]