The output from a pesticiie screening model indicated that chemicals with low Henry’s Law constants (A,,) will tend to accumulate at the soil surface when water is evaporating, resulting in an increased volrtilixation with time. Volatilixation losses and surface distributions of two pesticides with widely differing KH were measured to test the predictions of the screening model, particularly wi...

A numerical model is developed to predict the aqueous concentrations of sparingly soluble compounds resulting from oil, fuel, or chemical spills onto rivers. The model computes the concentration of compounds both in the slick phase and in the aqueous phase by simulating the processes that affect the fate of the spilled compound. Processes simulated by the model include spreading and drifting of...

The volatilization and soft ionization of complex neutral macromolecules at low energies has remained an outstanding challenge for several decades. Most volatilization techniques in mass spectrometry produce ions already in the source and most of them lead to particle velocities in excess of several hundred meters per second. For many macromolecules, post-ionization is inefficient since electro...

Recent work at Clemson University has provided 32 new data sets of ammonia volatilization losses during sprinkler irrigation of liquid manure. These 32 observations were pooled with 23 additional data sets that were available in the literature. The combined data includes losses from traveling gun, center pivot, and impact sprinkler irrigation of dairy, swine, and beef manure. Manure type did no...

Of 100 strains of iron-oxidizing bacteria isolated, Thiobacillus ferrooxidans SUG 2-2 was the most resistant to mercury toxicity and could grow in an Fe(2+) medium (pH 2.5) supplemented with 6 microM Hg(2+). In contrast, T. ferrooxidans AP19-3, a mercury-sensitive T. ferrooxidans strain, could not grow with 0.7 microM Hg(2+). When incubated for 3 h in a salt solution (pH 2.5) with 0.7 microM Hg...

Mangrove killifish, Rivulus marmoratus, are tolerant of prolonged periods of air exposure (>30 days). Air-exposed R. marmoratus eliminate more than 40% of their total ammonia through NH(3) volatilization; however, the sites and mechanisms are unclear. We hypothesized that the cutaneous surface is an important site of NH(3) volatilization in air-exposed R. marmoratus. Ion-selective microelectrod...

The objectives of this study were to evaluate the effects of different fertilizer types and application rates on ammonia volatilization loss and to explore nitrogen distribution and nitrogen use efficiency using the 15N isotope tracing technique in different alkaline salt-affected conditions in the Songnen Plain, Northeast China. The results showed a decreasing trend in ammonia volatilization l...

Selenium (Se) is an essential micronutrient for animals and humans but becomes toxic at high dosage. Biologically based Se volatilization, which converts Se into volatile compounds, provides an important means for cleanup of Se-polluted environments. To identify novel genes whose products are involved in Se volatilization from plants, a broccoli (Brassica oleracea var italica) cDNA encoding COQ...

Golf course putting greens typically receive high pesticide applications to meet high quality demands. Research on pesticide fate in turf ecosystems is important to better understand the potential impact of pesticide use on the environment and human health. This research was conducted to evaluate the environmental fate of two commonly used insecticides--trichlorfon (dimethyl 2,2,2-trichloro-1-h...