Water can be removed from pig slurry by evaporation, through the application of wasted heat from a power plant or from other processes. Apart from obtaining a concentrate with an obviously higher nutrient concentration than the original slurry, another objective of water removal is to obtain water as condensate, which could be reused. The objective of this work was to study the vacuum evaporati...

Samples of untreated groundwater from 1255 domestic drinking-water wells and 242 public supply wells were analyzed as part of the National Water-Quality Assessment Program of the U.S. Geological Survey between 1992 and 1999. Wells were sampled to define the regional quality of the groundwater resource and, thus, were distributed geographically across large aquifers, primarily in rural areas. Fo...

Anthropogenic enrichment of reactive nitrogen (Nr) deposition is an ecological concern. We use the adjoint of a global 3-D chemical transport model (GEOS-Chem) to identify the sources and processes that control Nr deposition to an ensemble of biodiversity hotspots worldwide and two U.S. national parks (Cuyahoga and Rocky Mountain). We find that anthropogenic sources dominate deposition at all c...

In many regions of China, very rapid economic growth has been accompanied by air pollution caused by vehicle emissions. In one of these regions, the Pearl River Delta, the variations of ground-level ozone and its precursors were investigated. Overall, the ambient concentrations of NO(2) increased quickly between 1995 and 1996, but then slightly decreased due to stringent nitrogen oxide (NO(x)) ...

This study presents the results of a paper of urban spatial structure and exceedances of the 8-h national ambient air quality standard for ozone in 45 large US metropolitan regions. Through the integration of a published index of sprawl with metropolitan level data on annual ozone exceedances, precursor emissions, and regional climate over a 13-year period, the association between the extent of...

Organic aerosol formation in the atmosphere is investigated via the developpement of a new model named H2O (Hydrohilic/Hydrophobic Organics). First, a parameterization is developped to take into account secondary organic aerosol formation from isoprene oxidation. It takes into account the e ect of nitrogen oxides on organic aerosol formation and the hydrophilic properties of the aerosols. This ...

background: toluene is a volatile organic compound, one of 189 hazardous air pollutants (hap s ) and the most important pollutant found in most industries and indoor environments; owing to its adverse health, toluene must be treated before being released into the environment. methods : in this research study, a continuous-flow system (including an air compressor, silica gel filters and activate...

A considerable fraction of the Earth's organic carbon exists in dissolved form in seawater. To investigate the roles of planktonic marine microbes in the biogeochemical cycling of this dissolved organic matter (DOM), we performed controlled seawater incubation experiments and followed the responses of an oligotrophic surface water microbial assemblage to perturbations with DOM derived from an a...

Few studies have investigated associations between nonoccupational exposure to ambient volatile organic compounds and lung cancer. We conducted a case-control study of 445 incident lung cancers and 948 controls (523 hospital, 425 general population) in Toronto, Ontario, Canada, between 1997 and 2002. Participants provided information on several risk factors, including tobacco use, secondhand ex...

Several workers have studied translocation forms of nitrogen in the xylem sap of trees. It is generally assumed that the nitrogen compounds found in the sap are synthesized in the roots and serve as forms in which nitrogen moves to the tops of trees. Various organic compounds (e.g., amino acids, ureides) usually represent most of the nitrogen in the sap, with inorganic forms (e.g., nitrate, amm...