Numerous studies of ambient ozone (O3) in the Los Angeles (LA) area have found both increases and decreases in elevated O3 levels on weekends, depending on location and year. Since the mid-1990s, average daily maximum O3 levels have been higher on weekends than on weekdays throughout most of the area. We used the Comprehensive Air-Quality Model with extensions to investigate causes of weekday/w...

This study evaluates air quality model sensitivity to input and to model components. Simulations are performed using the California Institute of Technology (CIT) airshed model. Results show the impacts on ozone (O3) concentration in the South Coast Air Basin (SCAB) of California because of changes in: (1) input data, including meteorological conditions (temperature, UV radiation, mixing height,...

A set of air-water discharge induced by double DBD device has been designed to obtain hydrogen peroxide (H2O2) and ozone (O3) levels, simultaneously. How the H2O2 and O3 are being produced, which have extensively been studied by different experimental approaches such as air cooling, atomization amount, voltage applied, pH value and electrical conductivity (EC). The experimental results show tha...

Inhaled ozone (O3) reacts chemically with respiratory tract biomolecules where it forms covalently bound oxygen adducts. We investigated the fate of these adducts following inhalation exposure of rats to labeled ozone ((18)O3, 2 ppm, 6 hr or 5 ppm, 2 hr). Increased (18)O was detected in blood plasma at 7 hr post exposure and was continuously present in urine for 4 days. Total (18)O excreted was...

[1] Photolytic dissociation of molecular oxygen (O2) at wavelengths about 205 nm produces ozone (O3) in the upper tropical troposphere. In tropospheric chemistry models that ignore this process, the O3 abundance above 14 km in the tropics (a.k.a. Tropopause Transition Layer) is underestimated by 5 to 20 ppb. Even for models including O2 photolysis, uncertainty in the O2 cross sections yields si...

Urban O3 is produced by photochemical chain reactions that amplify background O3 in mixtures of gaseous nitrogen oxides (NOx) and organic molecules. Current thinking treats NOx and organics as independent variables that limit O3 production depending on the NOx to organic ratio; in this paradigm, reducing organics either has no effect or reduces O3. We describe a theoretical counterexample where...

The use of ozone (O3) gas as a therapy in alternative medicine has attracted skepticism due to its unstable molecular structure. However, copious volumes of research have provided evidence that O3's dynamic resonance structures facilitate physiological interactions useful in treating a myriad of pathologies. Specifically, O3 therapy induces moderate oxidative stress when interacting with lipids...

The atomic structure of ordered domains in Ba~Mg1/3Nb2/3)O3 and La-doped and undoped Pb~Mg1/3Nb2/3)O3 is studied by high-resolution Z-contrast imaging. The ordered domain structure in both doped and undoped Pb~Mg1/3Nb2/3)O3 is determined to be in agreement with the charge balanced random-layer model and inconsistent with the space-charge model. It is shown that La doping in Pb~Mg1/3Nb2/3)O3 enh...

Prediction equations developed from previous ozone (O3) exposure studies suggested that athletes exercising at near competitive intensities would be subject to alteration of pulmonary function during exposure to relatively low concentrations of O3. Accordingly we exercised seven trained athletes for 1 h at 75% of maximal O2 consumption in both room air and a 0.21 ppm O3 environment. Pulmonary f...

A ground-based Differential Absorption Lidar was employed to study the dynamics of atmospheric O3 within the planetary boundary layer of a basin in the 'Fichtelgebirge' mountains, NE Bavaria. In particular, the night-time dynamics of O3 linked to the ground were investigated. The Lidar system measured vertical profiles of O3 up to 1 km above ground. For detailed analysis of the night-time dynam...