Adriana L. Brachet-Cota and Gerardo Burton* Departamento de Qirimica Orgänica, Facultad de Cieneias Exaetas y Naturales, Universidad de Buenos Aires, Pabellön 2, Ciudad Universitaria, 1428 Buenos Aires, Argentina Z. Naturforsch. 43b, 491-495 (1988); received November 2, 1987 6/3-Hydroxypregnanes, Mercuric Oxide, Oxidation, /3-Fragmentation. Hypoiodite Reaction Oxidation of 6/3-hydroxyprogestero...

The isotopically substituted nitrous oxide species 14N14NO, 15N14NO, 14N15NO and 15N15NO were investigated by ultra-violet (UV) absorption spectroscopy. High precision cross sections were obtained for the wavelength range 181 to 218 nm at temperatures of 233 and 283 K. These data are used to calculate photolytic isotopic fractionation constants as a function of wavelength. The fractionation con...

Absolute quantum yields) Cl+Cl* for the formation of chlorine atoms were measured under collision-free conditions for the gas-phase dissociation of carbon tetrachloride (CCl 4) after pulsed laser photoexcitation at 193 and 135 nm. By means of a photolytic calibration method, where the gas-phase photolysis of HCl was utilized as a reference, values of) Cl+Cl* (193 nm) = 1.5 ± 0.1 and) Cl+Cl* (13...

The 1990 Clean Air Act Amendments prompted an increased urgency to find new ways to treat airstreams containing volatile organic compounds, which affect the nitrogen photolytic cycle and help produce ground-level ozone, hazardous air pollutants, and odorous air emissions such as hydrogen sulfide. Scientists at the New Jersey company Envirogen have adapted traditional biofiltration technology to...

Abstract. Nucleation rates involving sulfuric acid and water measured in a photolytic flow reactor have decreased considerably over time period of several years. Results show that the system – reactor, gas supplies lines, meters, valves, H2SO4 photo-oxidant sources has reached baseline stability yields nucleation information such as cluster free energies. The rate is punctuated by temporary bur...

Neonicotinoids are now the third most abundantly used insecticides worldwide and account for over 80% of the seed treatment market. They are used for pest management on hundreds of crops in agriculture, horticulture, and forestry. Neonicotinoids are also used to control insect pests in pets such as dogs, as well as in livestock and in aquaculture. These insecticides are registered for use in ov...

BACKGROUND Ultraviolet photodegradation products from pesticides form both in the field and during water treatment. OBJECTIVES We evaluated the photolytic breakdown of the organophosphate pesticide chlorpyrifos (CPF) in terms of both the chemical entities generated by low-pressure ultraviolet C irradiation and their potential as developmental neurotoxicants. METHODS We separated by-products...