Carbohydrates are important molecular components of living matter. While spectroscopic and computational studies have been performed on carbohydrates in the electronic ground state, the lack of a chromophore complicates the elucidation of the excited-state properties and the photochemistry of this class of compounds. Herein, we report on the first computational investigation of the singlet phot...

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...

In order to improve the traditional methods of procyanidins extracting, ultrasonic-assisted filtration was used in the process of extracting proan-thocyanidin which was from membrane concentration of grape seed. Through the mechanism analysis of ultrasonic-assisted ultrafiltration, ultrasonic is able to alleviate the phenomenon of concentration polari-zation, so the efficiency of extracting pro...

We quantify the hygroscopic properties of particles freshly emitted from biomass burning and after several hours of photochemical aging in a smog chamber. Values of the hygroscopicity parameter, κ , were calculated from cloud condensation nuclei (CCN) measurements of emissions from combustion of 12 biomass fuels commonly burned in North American wildfires. Prior to photochemical aging, the κ of...

In ultrasonic array imaging, 3D ultrasonic wavefields are normally recorded by an ultrasonic piezo array transducer. Its performance is limited by the configuration and size of the array transducer. In this paper, a method based on digital holographic interferometry is proposed to record the 3D ultrasonic wavefields instead of the array transducer, and the measurement system consisting of a pul...