COHERENT SYNCHRONIZATION OF PYRIDINE DIMERIZATION REACTIONS AND DECOMPOSITION OF “GREEN OXIDANTS” – H2O2 AND N2O

In recent years, hydrogen peroxide and nitrous oxide (1) "green oxidants" – have attracted much attention of researchers as a selective oxidizing agent for the catalytic oxidation of pyridine bases. In this regard, the reaction of pyridine oxidation by hydrogen peroxide and nitrous oxide under homogeneous conditions, in the gas phase, without the use of catalysts, at atmospheric pressure, has been experimentally investigated. Areas of selective oxidation of pyridine with hydrogen peroxide and nitrous oxide have been established, and optimal conditions have been found for obtaining valuable raw materials required in the petrochemical, chemical, and pharmaceutical industries

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Fluorescence of BODIPY Dyes in Gas Phase at near Ambient Conditions

10.26434/chemrxiv.11639931.v1 ◽

2020 ◽

Author(s):

Kseniya A. Mariewskaya ◽

Denis Larkin ◽

Yuri Samoilichenko ◽

Vladimir Korshun ◽

Alex Ustinov

Keyword(s):

Gas Phase ◽

Molecular Interactions ◽

Atmospheric Pressure ◽

Fluorescence Spectra ◽

Visible Range ◽

Intrinsic Properties ◽

Ambient Conditions ◽

Ideal Model ◽

Molecular Fluorescence ◽

Tesla Coil

Molecular fluorescence is a phenomenon that is usually observed in condensed phase. It is strongly affected by molecular interactions. The study of fluorescence spectra in the gas phase can provide a nearly-ideal model for the evaluation of intrinsic properties of the fluorophores. Unfortunately, most conventional fluorophores are not volatile enough to allow study of their fluorescence in the gas phase. Here we report very bright gas phase fluorescence of simple BODIPY dyes that can be readily observed at atmospheric pressure using conventional fluorescence instrumentation. To our knowledge, this is the first example of visible range gas phase fluorescence at near ambient conditions. Evaporation of the dye in vacuum allowed us to demonstrate organic molecular electroluminescence in gas discharge excited by electric field produced by a Tesla coil.

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Biogeochemical Alteration of an Aquifer Soil during In Situ Chemical Oxidation by Hydrogen Peroxide and Peroxymonosulfate

Environmental Science & Technology ◽

10.1021/acs.est.0c06206 ◽

2021 ◽

Author(s):

Eun-Ju Kim ◽

Saerom Park ◽

Sawaira Adil ◽

Seunghak Lee ◽

Kyungjin Cho

Keyword(s):

Hydrogen Peroxide ◽

Chemical Oxidation ◽

In Situ Chemical Oxidation ◽

Oxidation By Hydrogen Peroxide

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Towards High Efficacy of Pd-Au/C Catalyst for Tetrachloromethane Hydrodechlorination

Chemistry ◽

10.3390/chemistry3010025 ◽

2021 ◽

Vol 3 (1) ◽

pp. 338-359

Author(s):

Magdalena Bonarowska ◽

Zbigniew Kaszkur ◽

Krzysztof Matus ◽

Alicja Drelinkiewicz ◽

Tomasz Szumełda ◽

...

Keyword(s):

Microwave Irradiation ◽

Gas Phase ◽

Thermal Activation ◽

Supported Catalysts ◽

Carbon Support ◽

Thermal Reduction ◽

Microwave Oven ◽

Optimal Conditions ◽

Catalyst Activation ◽

Critical Part

We present an efficient strategy for synthesising the PdAu catalysts with a homogeneous PdAu alloy phase for environmentally important hydrodechlorination of tetrachloromethane in the gas phase. The synthesis of carbon-supported catalysts involved two major steps: (i) incorporation of palladium and gold nanoparticles into carbon support and (ii) activation of the catalysts. The critical part of this work was to find the optimal conditions for both steps. Thus, the incorporation of the nanoparticles was carried out in two ways, by impregnation and direct redox reaction method using acetone solutions of metal precursor salts. The activation was performed either by a conventional thermal reduction in hydrogen or flash irradiation in a microwave oven. The homogeneity and structure of the PdAu alloy were found to depend on the catalyst activation method critically. In all cases, we observed better homogeneity for catalysts that were subject to microwave irradiation. Moreover, the flash microwave irradiation of prepared catalysts provided catalysts of better stability and selectivity towards the desired products (hydrocarbons) in the hydrodechlorination of tetrachloromethane as compared to the catalyst obtained by conventional thermal activation in hydrogen.

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Both near ultraviolet radiation and the oxidizing agent hydrogen peroxide induce a 32-kDa stress protein in normal human skin fibroblasts.

Journal of Biological Chemistry ◽

10.1016/s0021-9258(18)47869-6 ◽

1987 ◽

Vol 262 (30) ◽

pp. 14821-14825

Author(s):

S M Keyse ◽

R M Tyrrell

Keyword(s):

Hydrogen Peroxide ◽

Ultraviolet Radiation ◽

Human Skin ◽

Stress Protein ◽

Skin Fibroblasts ◽

Oxidizing Agent ◽

Human Skin Fibroblasts ◽

Normal Human Skin ◽

Near Ultraviolet ◽

Normal Human

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Autothermal Gas-Phase Oxidative Dehydrogenation of Ethane to Ethylene at Atmospheric Pressure

Industrial & Engineering Chemistry Research ◽

10.1021/acs.iecr.1c00678 ◽

2021 ◽

Author(s):

Hassan J. Dar ◽

Hugo A. Jakobsen ◽

Kumar R. Rout ◽

Klaus. J. Jens ◽

De Chen

Keyword(s):

Gas Phase ◽

Oxidative Dehydrogenation ◽

Atmospheric Pressure ◽

Oxidative Dehydrogenation Of Ethane

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Ion chemistry of second-row transition metals in hydrocarbon flames: cations and anions of Y, Zr, Nb, and Mo

Canadian Journal of Chemistry ◽

10.1139/v95-280 ◽

1995 ◽

Vol 73 (12) ◽

pp. 2263-2271 ◽

Cited By ~ 7

Author(s):

Christine C.Y. Chow ◽

John M. Goodings

Keyword(s):

Transition Metals ◽

Gas Phase ◽

Atmospheric Pressure ◽

Chemical Ionization ◽

Negative Ions ◽

Ion Concentration ◽

Oxidation States ◽

Metallic Ions ◽

Ion Chemistry ◽

Hydrocarbon Flames

A pair of laminar, premixed, CH4–O2 flames above 2000 K at atmospheric pressure, one fuel-rich (FR) and the other fuel-lean (FL), were doped with ~10−6 mol fraction of the second-row transition metals Y, Zr, Nb, and Mo. Since these hydrocarbon flames contain natural ionization, metallic ions were produced in the flames by the chemical ionization (CI) of metallic neutral species, primarily by H3O+ and OH− as CI sources. Both positive and negative ions of the metals were observed as profiles of ion concentration versus distance along the flame axis by sampling the flames through a nozzle into a mass spectrometer. For yttrium, the observed ions include the YO+•nH2O (n = 0–3) series, and Y(OH)4−. With zirconium, they include the ZrO(OH)+•nH2O (n = 0–2) series, and ZrO(OH)3−. Those observed with niobium were the cations Nb(OH)3+ and Nb(OH)4+, and the single anion NbO2(OH)2−. For molybdenum, they include the cations MoO(OH)2+ and MoO(OH)3+, and the anions MoO3− and MoO3(OH)−. Not every ion was observed in each flame; the FL flame tended to favour the ions in higher oxidation states. Also, flame ions in higher oxidation states were emphasized for these second-row transition metals compared with their first-row counterparts. Some ions written as members of hydrate series may have structures different from those of simple hydrates; e.g., YO+•H2O = Y(OH)2+ and ZrO(OH)+•H2O = Zr(OH)3+, etc. The ion chemistry for the production of these ions by CI in flames is discussed in detail. Keywords: transition metals, ions, flame, gas phase, negative ions.

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