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Showing 1 to 20 of 30 for “"HO2+"”.
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Kinetics of HO2 abstraction of H atoms from hydrocarbons and thermochemical properties of urethane monomers and radicals
SECTION I: Kinetics of HO_2 Abstraction of H Atoms From Hydrocarbons Structures, internal rotational barriers and ideal gas thermochemical properties, [Delta]H_{f98} for representative series of transition states for abstraction of H atoms from primary, secondary and tertiary hydrocarbons by the …
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The nuclear spin dependence of the reaction of H3+ with H2 and the proposed spectroscopic investigation of HO2+
High-resolution spectroscopy of molecular ions has been proven to be a difficult endeavor. Generating significant quantities of the desired ions and discriminating ions from neutrals are among some of the many difficulties surrounding the spectroscopic studies of these species. Despite these …
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Effects of Water Vapor on the Kinetics of the Methylperoxy Radical Self-reaction and Reaction with Hydroperoxy
The gas phase reactions of CH3O2 + CH3O2, HO2 + HO2, and CH3O2 + HO2 in the presence of water vapor have been studied at temperatures between 263 and 303 K using laser flash photolysis coupled with UV time-resolved absorption detection at 220 nm and 260 nm. Water vapor concentration was quantified …
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Messungen der atmosphärischen Radikale OH, HO 2 , RO 2 sowie des Ultraspurengases Schwefelsäure : Weiterentwicklung, Kalibration und Einsatz einer hochempfindlichen massenspektrometrischen Analysemethode
OH-, HO2- und RO2-Radikale spielen beim oxidativen Abbau von Schadstoffen in der Atmosphäre eine fundamentale Rolle. Bei diesen Oxidationsprozessen wird unter anderem auch gasförmige Schwefelsäure gebildet, die zur Partikelbildung einen wichtigen Beitrag leistet. Zur selektiven Messung dieser …
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MEASUREMENTS AND MODEL PREDICTIONS OF HYDROXYL RADICAL, PEROXY RADICALS, AND NITROUS ACID: EVIDENCE OF MISSING SOURCES OR SINKS IN FORESTED AND INDOOR ENVIRONMENTS
… cycle between OH, the hydroperoxy radical (HO2), and organic peroxy radical (RO2). Due to its importance in the atmosphere, there is a substantial body of literature investigating ROX (≡ OH + HO2 + RO2) chemistry in the outdoor environment, but few measurements occurring indoors, where …
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Molecular Dynamics of Interfacial Phenomena at Air/ice, Air/water, and Air/salt Water Interfaces
… and phenanthrene), ROSs (O3, OH, H2O2 and HO2) and GLVs (2-methyl-3-buten-2-ol (MBO) and methyl salicylate (MeSA)) on atmospheric air/water or air/ice interfaces was investigated using classical molecular dynamics (MD) simulations and potential of mean force (PMF) calculations. All …
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A single-crystal EPR study of radiation-induced defects in selected silicates
… for three months reveal a hydroperoxy radical HO2 with complex proton hyperfine and superhyperfine structures. The single-crystal EPR spectra of this HO2 radical, measured from 4 K to 275 K, confirm two reversible phase transitions at ~98 K and ~21 K. Spin-Hamiltonian parameters show that the …
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Recruiting, interviewing, and hiring of executive trainees by apparel specialty chain, conventional department, and discount department stores
… store format and recruiting (Ho1) interviewing (Ho2), and hiring (Ho3) procedures used for entry-level executive trainees. Because significant differences at the .05 level were found for on-campus recruiting, Ho1 was rejected. Significant differences were found at the .05 level for 5 of 35 …
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Exploring the Chemistry of Methoxide with Oxygen through Photoelectron Imaging Spectroscopy
… CH3O and O2 to produce the hydroperoxide anion (HO2) is leveraged to investigate the photoelectron angular distributions as a function of electron kinetic energy, corresponding to photodetachment to each the ground X 2A′′ and excited A 2A′ electronic states of the neutral HO2 radical. These are …
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MEASUREMENTS OF ATMOSPHERIC RADICALS IN AMBIENT AND INDOOR ENVIRONMENTS: OUTDOOR-INDOOR RELATIONSHIPS, INDOOR FORMATION MECHANISMS, AND INSTRUMENTAL ANALYSIS
Hydroxyl (OH), hydroperoxy (HO2), and peroxy (RO2) radicals are key to atmospheric oxidation, critically altering the chemistry of the air we breathe. Radical reactions initiate oxidation of volatile organic compounds (VOCs), which in the presence of nitrogen oxides (NOx) can form ozone and …
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Atmosphärische gasförmige Vorläufer von Aerosol und Ozon: Messungen mit CIMS-Methoden auf einem Flugzeug und am Boden
… und Methanol sind wichtige Vorläufer von HOx(=OH,HO2) und Ozon in der oberen Troposphäre und untersten Stratosphäre. In der planetaren Grenzschicht wurde ein Tagesgang der Konzentrationen gasförmiger Schwefelsäure beobachtet, wobei mittags die höchsten Werte vorkommen, die gelegentlich eine …
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A study of the tropospheric oxidation of volatile organic compounds using chemical ionization mass spectrometry
… Torr. The kinetics of the reaction of CH302 with HO2 were then examined. Aromatics are another important class of trace species found in the troposphere. The daytime oxidation of toluene is initiated by reaction with the OH radical. Rate coefficients and detailed mechanistic information for this …
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Kinetische Untersuchungen der Oxidation von luftgetragenen Rußpartikeln mittels ESR- und FTIR-Spektroskopie
… Spurengase O3, NO2, N2O5/NO3, HNO3 und HOONO2/HO2 an luftgetragenen Rußpartikeln in der Aerosolkammer AIDA bei atmosphärisch relevanten Bedingungen untersucht. Nach dem schnellen Anfangsverlust von etwa einem Monolagen-Äquivalent Ozon sinkt die Reaktionswahrscheinlichkeit auf einen Wert, der um …
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Uncertainties in estimates of the oxidative capacity of the urban atmosphere : a modeling and measurement approach
… OH by about 25% and severely under-predicts HO2 by a factor of 2 to 3 suggesting that the radical formation pathways in current state of the art AQMs should be revised.
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The Relationship Between Time-On-Task in Computer-Aided Instruction and the Progress of Developmental Reading Students at the University of Texas at Brownsville and Texas Southmost College
… on the TASP scores of the population studied. Ho2 - Correlation and linear regression correlation showed that females made significantly better gains on the TASP test from CAI than males. Ho3 - Correlation and linear regression correlation showed that low-achiever students made no better gains …
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Oxidation Mechanisms of Tetrahydrofolic Acid, Tetrahydrobiopterin and Related Compounds
… the chain carrier is the hydroperoxyl radical (HO2.) and that intermediate hydroperoxides are not involved. Quinonoid dihydropterins are obligatory intermediates, their rearrangement leading to the observed products. Oxygen-18 labelling experiments show that the autoxidative ring contraction of …
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Investigations of Asphaltene-Metal Interactions
… (a Schlumberger company) and termed as MD and HO2 asphaltenes. Most extensive experimentations and analyses were carried out for Cold Lake asphaltenes. The same procedure was applied for the other asphaltene samples. The kinetic analyses of Cold Lake and MD asphaltenes indicated that the …
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Evaluation of an Electro-Disinfection Technology as an Alternative to Chlorination of Municipal Wastewater Effluents
… substances such as H2O2, [O], •OH, and •HO2 provide the strong disinfecting action of the system within a short contact time. The bactericidal efficiency of the process generally increased with the current density and contact time, and the impact of these factors was much larger than that …
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Vocational and academic secondary educator's perceptions of career education in Class A-AAAA schools in Wyoming
… chi square test of significance was used to test Ho2-Ho4. Findings indicated differences related to teacher type. Academic teachers were less likely to support career education than vocational teachers. Vocational teachers viewed teachers as the key personnel in career education. Academic teachers …
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Laboratory and Mechanistic Studies of Volatile Organic Carbon Oxidation Systems in the Atmosphere
… important radical species including NOx and HO2. Chamber experiments are often conducted to measure VOC oxidation in a controlled laboratory setting, but these studies are may be complicated by vapor deposition on chamber surfaces and potential VOC decomposition in the Chemical Ionization …
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