Mass-independent sulfur isotope signatures are observed in Archean and early Paleoproterozoic sedimentary sulfate and sulfide minerals, and provide the most robust constraints on early atmospheric oxygen levels. Smaller mass-independent sulfur isotope anomalies are observed in ice cores and interpreted as a tracer of stratospheric volcanic loading. Photochemistry of sulfur dioxide (SO 2) has be...

Ž . In this paper, we find that sulfur dioxide SO emissions by electric utilities declined from 2 1985 to 1993 for reasons largely unrelated to the emission reduction mandate of Title IV of the 1990 Clean Air Act Amendments. The principal reason appears to be the decline in rail rates for low-sulfur western coal delivered to higher-sulfur coal-fired plants in the Midwest. Consequently, there is...

Asthma is one of the most common diseases in childhood, which has been increased during last decade because of epidemiological pattern changes with climate and industrialization of the communities. There are some controversies on the relationship between air pollution and asthma. Tehran, as the capital of Iran, is one of the densest populations and is one of the most polluted cities in the worl...

The objective of this study is to determine the occupant/driver exposure in public transport buses running on biodiesel (B20) and ultra low sulfur diesel (ULSD) buses in the city of Toledo, Ohio. This paper also presents a protocol used for carrying out an experimental study involving continuous monitoring of real-time in-vehicle pollutant concentrations. In-vehicle concentrations of six air po...

increasing energy demands associated with economic growth and industrialization have resulted in dramatic increases in air pollution emissions. air pollution damages the plant mainly by disrupting cell homeostatic conditions.in the present study, diverse plant criteria indicating air pollution from different levels including cell biochemistry, leaf and tree crown in the plane-tree were determin...

The authors investigated the relation between ambient concentrations of five of the Environmental Protection Agency's criteria pollutants and asthma exacerbations (daily symptoms and use of rescue inhalers) among 990 children in eight North American cities during the 22-month prerandomization phase (November 1993-September 1995) of the Childhood Asthma Management Program. Short-term effects of ...

Over ten years ago we published a series of papers on the metabolism of Thiobacillsthiooxidakrs, an autotrophic bacterium discovered by Waksman and Joffe (1922), which oxidizes sulfur to sulfuric acid (LePage, 1942; LePage and Umbreit, 1943; O'Kane, 1942; Umbreit, 1947; Umbreit and Anderson, 1942; Umbreit et al., 1942; Vogler, 1942a, b; Vogler et al., 1942; Vogler and Umbreit, 1941, 1942). The ...