Small-scale and household low-cost technologies to provide water free of arsenic for drinking purposes, suitable for isolated rural and periurban areas not connected to water networks in Latin America are described. Some of them are merely adaptation of conventional technologies already used at large and medium scale, but others are environmentally friendly emerging procedures that use local ma...

Diabatic potential energy surfaces are a convenient starting point for dynamics calculations of photochemical processes, and they can be calculated by the fourfold way direct diabatization scheme. Here we present an improved definition of the reference orbital for applying the fourfold way direct diabatization scheme to ammonia. The improved reference orbital is a geometry-dependent hybrid orbi...

In the ISA, EPA indicates that many of the overall conclusions remain generally the same as the last National Ambient Air Quality Standard (NAAQS) review which was completed in 2008. However, contrary to the EPA’s statement, the ISA includes conclusions regarding a wide-range of health effects including stronger causal associations for both short-term and long-term exposures to ozone and newer ...

The photodegradation of pesticides is reviewed, with particular reference to the studies that describe the mechanisms of the processes involved, the nature of reactive intermediates and final products. Potential use of photochemical processes in advanced oxidation methods for water treatment is also discussed. Processes considered include direct photolysis leading to homolysis or heterolysis of...

Model calculations indicate that the lower ionosphere of Saturn is controlled by photochemical processes, with basic features similar to the Jovian ionosphere. The scale height of the upper ionosphere is large (•3350 km). A peak electron density of •10•cm -s 2250 km above a 10•9cm -a reference level is expected assuming an eddy coefficient at the homopause of 1.3 x 10øcmas -• and a relatively h...

A novel setup for the direct determination of the quantum yield in photocatalytic and photochemical processes is reported. It combines the opto-electronic measurement of the absorbed amount of light with established quantitative chemical analysis of the products. High power visible LEDs are found to be convenient light sources for the illumination without the need for spectral filtering. The LE...

Saturating pulse fluorescence measurements, well known from studies of higher plants, were applled to cultures of the chlorophyte Dunallella tertiolecta Photochemical and non-photochemlcal quenching, and the photochemlcal yield and photochemical efficiency of photosystem 11, were deternuned for cultures of D tertiolecta growing under varying light intensit~es Photosynthetic efflciencies appeare...

Morphological changes of microvessels of cerebral cortex were evaluated in a model of cerebral infarction initiated by a photochemical reaction. Rats were treated with intravenous injection of rose Bengal and irradiated from a halogen lamp source through an intact cranium to precipitate microvascular damage. Investigations in transmission and scanning electron microscopy revealed platelet aggre...

In order to assess the situation with air pollution by ozone in Colorado region during sunny part of the year (April to September), recently introduced photochemical pollution (PP) indicators have been applied on acquired ozone data, i.e. hourly ozone volume averages. PP indicators show very low values at the majority of stations except for the two located in Denver and Arvada which are located...

Photochemical detoxification reactions have been used to generate photooxidised snake venom product of 0 pharmacologic and therapeutic significance. Photochemical method by exposure to UV radiation for120 min. at 30 C in the presence of methylene blue was used to generate photooxidised aflatoxin B1 product (POAFB1). TLC revealed three spots under UV light illumination and HPLC analysis showed t...