THE REACTION OF t-BUTYL ALCOHOL VAPOR WITH Hg 6(3P1) ATOMS

1963 ◽  
Vol 41 (11) ◽  
pp. 2849-2860 ◽  
Author(s):  
Arthur R. Knight ◽  
Harry E. Gunning
Keyword(s):  
Nitric Oxide ◽  
Butyl Alcohol ◽  
Continuous Illumination ◽  
Quantum Yields ◽  
Static System ◽  
Reaction Products ◽  
Subsequent Reaction ◽  
Alcohol Vapor ◽  
Intermittent Illumination ◽  
In Parenthesis

The nature of the decomposition of t-butyl alcohol vapor, photosensitized by Hg 6(3P1) atoms in a static system at room temperature, has been examined under a variety of conditions of continuous and intermittent illumination. The inhibiting effect of nitric oxide has also been studied, as well as the influence of added inert gas.In the decomposition of pure substrate, the reaction products, with the initial quantum yields, Φ°, under continuous illumination in parenthesis, were: H2 (0.045), Me2CO (0.090), CO (0), CH4 (0.015), C2H6 (0.030) together with lesser amounts of C3H8, Me3CH, Me3CMe, and Me3COMe. On addition of nitric oxide, Me3CONO, Me2CO, N2O, N2, H2O, and trace quantities of H2 and CO were the only products observed.The reaction[Formula: see text]is proposed as the primary process in the decomposition and kinetic evidence is presented that the initially formed t-butoxy radicals possess excess energy and that their principal subsequent reaction is unimolecular cleavage into acetone and methyl. The results furthermore indicate that the substrate itself is quite inert to abstractive attack by the primary radicals.

THE REACTION OF ETHANOL VAPOR WITH Hg 6(3P1) ATOMS

1961 ◽  
Vol 39 (12) ◽  
pp. 2466-2473 ◽  
Author(s):  
Arthur R. Knight ◽  
Harry E. Gunning
Keyword(s):  
Dark Period ◽  
Hydrogen Abstraction ◽  
Ethanol Vapor ◽  
Continuous Illumination ◽  
Quantum Yields ◽  
Maximum Value ◽  
Volatile Products ◽  
Intermittent Illumination ◽  
Heavy Product ◽  
Static Conditions

The reaction of ethanol vapor with Hg 6(3P1) atoms has been investigated under static conditions at 25 °C. To determine the nature and efficiency of the primary process, the reaction has been studied in the presence of nitric oxide, and also under conditions of inter mittent illumination. For the pure substrate the volatile products were H2 (0.53), CH3CHO (0.08), CO (0.025), C2H6 (0.006), and CH4 (0.002), with the bracketed numbers representing the quantum yields at zero exposure time. The heavy product was a mixture of butanediols containing 90% 2,3-, 8% 1,3-, and 2% 1,4-butanediol. With 20% added NO, the products were EtONO (0.25), N2O (0.14), H2O, and H2 (0.017). Under intermittent illumination, the quantum yield (Φ) of H2 formation for pure substrate was measured as a function of the light period (tL) and the dark period (tD). For maximum values of Φ(H2), it was found that tD had to exceed ca. 120 msec. Under these conditions, Φ(H2) rose linearly with decreasing log tL, to a maximum value of 0.96 at tL less than 0.4 msec.From the study it is concluded that ethanol reacts with Hg 6(3P1) atoms to form ethoxy radicals and H atoms with at least 96% efficiency. The primary ethoxy radicals disappear by hydrogen abstraction from the substrate to form mainly CH3CHOH radicals. Under continuous illumination the low value (0.53) for Φ(H2) is caused principally by the addition of H atoms to the CH3CHOH radicals.

scholarly journals Gas-phase reaction products and yields of terpinolene with ozone and nitric oxide using a new derivatization agent

2015 ◽  
Vol 122 ◽  
pp. 513-520 ◽  
Author(s):  
Jason E. Ham ◽  
Stephen R. Jackson ◽  
Joel C. Harrison ◽  
J.R. Wells
Keyword(s):  
Nitric Oxide ◽  
Gas Phase ◽  
Phase Reaction ◽  
Reaction Products ◽  
Gas Phase Reaction

Mg-K-Fe fluid producing mineral reactions, metasomatism and microfabric development during formation of nodular sillimanite-gneiss in the middle crust

2021 ◽  
Author(s):  
Ane K. Engvik ◽  
Claudia A. Trepmann ◽  
Håkon Austrheim
Keyword(s):  
Stress Condition ◽  
White Mica ◽  
Ore Deposits ◽  
Preferred Orientation ◽  
Reaction Products ◽  
Subsequent Reaction ◽  
Crystallographic Preferred Orientation ◽  
Mineral Reaction ◽  
Metasomatic Fluid ◽  
Mineral Replacement

<p>The Proterozoic gneisses of the Bamble lithotectonic domain (south Norway) underwent intense scapolitisation caused by K- and Mg-rich fluids and extensive albitisation with formation of numerous ore deposits.</p><p>By detailed studies of mineral reaction fabrics we document release of the chemical active Mg, K and Fe-components forming the metasomatic fluid: Breakdown of biotite to muscovite releases K, Mg, Fe, Si and H<sub>2</sub>O. As reaction products tiny Fe-oxide needles are present in the transforming rock. H<sub>2</sub>O is reacting with K-feldspar to produce additional amounts of white mica and quartz. During a subsequent reaction muscovite is replaced to sillimanite again releasing quartz and a K-rich fluid. The reactions form the peculiar sillimanite-nodular quartzite, but also well-foliated sillimanite-mica gneiss.</p><p>Optical and EBSD microfabric studies reveal a shape preferred orientation for quartz, but despite of a pronounced foliation, quartz does not show a crystallographic preferred orientation. A crystallographic preferred orientation is present for mica and sillimanite. Coarse micas show sutured boundaries to quartz, implying low nucleation rates, no crystallographic or surface-energy control during growth and no obvious crystallographic relationship to quartz.</p><p>Our study illustrates the transformation of a quartzofeldspatic lithology into sillimanite-bearing quartzite. The mineral replacement and deformation show ongoing metamorphic reactions during deformation. The microfabric data indicates reaction at non-isostatic stress condition. The deduced mineral replacement reactions document a source of K-, Mg- and Fe-rich metasomatic fluids necessary to cause the pervasive scapolitisation and Fe-deposition in the area. The mineral reactions and deformation produce rocks with a new mineralogy and structure; an increased understanding of these processes is important for the modelling of crustal building and geological history.</p>

A Study of Isobutylene-Nitric Oxide Reaction Products

1964 ◽  
Vol 29 (7) ◽  
pp. 1937-1942 ◽  
Author(s):  
L. V. Phillips ◽  
D. M. Coyne
Keyword(s):  
Nitric Oxide ◽  
Reaction Products

The gas-phase photolysis of 2-methyl-1,3-butadiene at 123.6 nm

1984 ◽  
Vol 62 (9) ◽  
pp. 1731-1735
Author(s):  
Valerie I. Lang ◽  
Richard D. Doepker
Keyword(s):  
Nitric Oxide ◽  
Hydrogen Sulfide ◽  
Gas Phase ◽  
Quantum Efficiency ◽  
Hydrogen Iodide ◽  
Quantum Yields ◽  
Primary Decomposition ◽  
Radical Scavengers ◽  
Molecule Reaction ◽  
Reaction Channels

The gas-phase photolysis of 2-methyl-1,3-butadiene has been investigated using krypton (123.6 nm) resonance radiation. The observed neutral products of the primary decomposition were vinylacetylene, ethylene, acetylene, methylacetylene, propylene, allene, 2-methy-1-buten-3-yne, pentatriene/1-penten-3-yne, 1,3-butadiene, 2-butyne and butatriene, listed in decreasing order of concentration. There was also evidence of the presence of several radical fragments: CH2/CH3, C2H3, C3H3, and C4H5. Quantum yields for each of the products were determined in the photolysis of 2-methyl-1,3-butadiene, performed both in the presence and the absence of additives. Nitric oxide and oxygen were employed as radical scavengers, while hydrogen sulfide and hydrogen iodide were used as radical interceptors. Twelve primary, neutral molecule, reaction channels were proposed and the quantum efficiency assigned for each. The ionization efficiency of 2-methyl-1,3-butadiene was established as n = 0.55 at 10.03 eV. No products formed exclusively via an ion–molecule pathway were identified and therefore the fate of the C5H8+ ion was not determined.

THE KINETICS OF CUPRENE GROWTH

1950 ◽  
Vol 28b (7) ◽  
pp. 358-372
Author(s):  
Cyrias Ouellet ◽  
Adrien E. Léger
Keyword(s):  
Nitric Oxide ◽  
Activation Energy ◽  
Carbon Monoxide ◽  
Apparent Activation Energy ◽  
Copper Catalyst ◽  
Maximum Velocity ◽  
Static System ◽  
Reaction Velocity ◽  
First Order ◽  
Kinetics Of

The kinetics of the polymerization of acetylene to cuprene on a copper catalyst between 200° and 300 °C. have been studied manometrically in a static system. The maximum velocity of the autocatalytic reaction shows a first-order dependence upon acetylene pressure. The reaction is retarded in the presence of small amounts of oxygen but accelerated by preoxidation of the catalyst. The apparent activation energy, of about 10 kcal. per mole for cuprene growth between 210° and 280 °C., changes to about 40 kcal. per mole above 280 °C. at which temperature a second reaction seems to set in. Hydrogen, carbon monoxide, or nitric oxide has no effect on the reaction velocity. Series of five successive seedings have been obtained with cuprene originally grown on cuprite, and show an effect of aging of the cuprene.

scholarly journals Edge stabilization in reduced-dimensional perovskites

2020 ◽  
Vol 11 (1) ◽  
Author(s):  
Li Na Quan ◽  
Dongxin Ma ◽  
Yongbiao Zhao ◽  
Oleksandr Voznyy ◽  
Haifeng Yuan ◽  
...  
Keyword(s):  
Structural Diversity ◽  
Continuous Illumination ◽  
Quantum Yields ◽  
Color Purity ◽  
Phosphine Oxides ◽  
Maximum Luminance ◽  
Light Emitting ◽  
Tunable Bandgap ◽  
Luminescence Color ◽  
Oxidative Attack

AbstractReduced-dimensional perovskites are attractive light-emitting materials due to their efficient luminescence, color purity, tunable bandgap, and structural diversity. A major limitation in perovskite light-emitting diodes is their limited operational stability. Here we demonstrate that rapid photodegradation arises from edge-initiated photooxidation, wherein oxidative attack is powered by photogenerated and electrically-injected carriers that diffuse to the nanoplatelet edges and produce superoxide. We report an edge-stabilization strategy wherein phosphine oxides passivate unsaturated lead sites during perovskite crystallization. With this approach, we synthesize reduced-dimensional perovskites that exhibit 97 ± 3% photoluminescence quantum yields and stabilities that exceed 300 h upon continuous illumination in an air ambient. We achieve green-emitting devices with a peak external quantum efficiency (EQE) of 14% at 1000 cd m−2; their maximum luminance is 4.5 × 104 cd m−2 (corresponding to an EQE of 5%); and, at 4000 cd m−2, they achieve an operational half-lifetime of 3.5 h.

scholarly journals Thermal Decomposition and Thermal Reaction Process of PTFE/Al/MnO2 Fluorinated Thermite

Materials ◽  
2018 ◽  
Vol 11 (12) ◽  
pp. 2451 ◽  
Author(s):  
Jun Zhang ◽  
Junyi Huang ◽  
Xiang Fang ◽  
Yuchun Li ◽  
Zhongshen Yu ◽  
...  
Keyword(s):  
Thermal Decomposition ◽  
Control Systems ◽  
Thermal Reaction ◽  
Reaction Process ◽  
Reaction Products ◽  
Subsequent Reaction ◽  
Comparison Results ◽  
Different Temperatures ◽  
Xrd Phase Analysis ◽  
Two Stages

To better understand the thermal decomposition and reaction process of a fluorine-containing powdery thermite, PTFE/Al/MnO2, reactions at different temperatures were investigated by the TG/DSC-MS technique. The corresponding reaction products were characterized with XRD phase analysis. Another three thermite materials, i.e., PTFE/Al, Al/MnO2, and PTFE/MnO2, were also prepared for comparison. Results showed that PTFE behaved as both oxidizer and reducer in PTFE/Al/MnO2 fluorinated thermite. The thermal decomposition and reaction process of as-fabricated ternary thermite could be divided into two stages—the mutual reaction between each of PTFE, Al, and MnO2 and the subsequent reaction produced between Al and Mn2O3/Mn3O4/MnF2. Compared with the three control systems, the specially designed ternary system possessed a shorter reaction time, a faster energy release rate, and a better heat release performance.

THE REACTION OF ISOPROPANOL VAPOR WITH Hg 6 (3P1) ATOMS: PART I. PURE SUBSTRATE

1962 ◽  
Vol 40 (6) ◽  
pp. 1134-1139 ◽  
Author(s):  
Arthur R. Knight ◽  
Harry E. Gunning
Keyword(s):  
Quantum Yield ◽  
Hydrogen Production ◽  
Exposure Time ◽  
Resonance Line ◽  
Light Period ◽  
Inert Gas ◽  
Quantum Yields ◽  
Volatile Product ◽  
Intermittent Illumination ◽  
Static Conditions

The reaction of isopropanol vapor with Hg 6(3P1) atoms has been investigated under static conditions at 25 °C under continuous and intermittent illumination. The effect of added inert gas and isolation of the 2537 Å Hg resonance line were also studied.The products of the reaction are H2 (0.72), CH3COCH3 (0.25), CO, CH4, C2H6, CH3CHO, and H2O, with the numbers in parentheses representing the quantum yields at zero exposure time. The non-volatile product remaining in the cell was a mixture of C6-glycols, containing 98.6% pinacol, 1.2% 2-methyl-2,4-pentanediol, and ca. 0.2% or less of 2,5-hexanediol.Under intermittent illumination, the quantum yield of hydrogen production, measured as a function of light period, tL, rose linearly with log tL, and had a constant value of unity for tL < 0.45 msec. A mechanism is proposed involving the primary formation with perfect efficiency of isopropoxy radicals and H atoms.

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