Research Watch
Air Quality Haze in Southeast Asia. Although numerous studies of forest fire plumes have been conducted in other parts of the world, this is the first to be carried out in Southeast Asia with the aim of identifying and quantifying chemical components in the haze, including known or suspected carcinogens, mutagens, and teratogens. (Muraleedharan, T. R., et al. "Chemical Characterization of the Haze in Brunei Darussalam During the 1998 Episode", Atmos. Environ. 2000 34 (17), 2725-2731)
Biogeochemistry Methane air-sea exchange. The authors report that the flux to the atmosphere appears to be the main sink for methane in the upper ocean and that microbial oxidation and downward eddy diffusion account for only 3% and 6%, respectively, of the total methane loss from the upper 300 m. (Holmes, M. E., et al. "Methane Production, Consumption, and Air-Sea Exchange in die Open Ocean: An Evaluation Based on Carbon Isotopic Ratios", Global Biogeochem. Cycles 2000 14 ((1 ,110)
Climate Atmospheric oxygen. The authors develop a dynamic feedback model of the coupled P, N, C, and 0 2 cycles and use perturbation analysis and a case study of the past 40 million years to test various feedback mechanisms that have been proposed to stabilize atmospheric oxygen. (Lenton, T. M.; Watson, J. "Redfield Revisited. 2. What Regulates the Oxygen Content of the Atmosphere?" Global Biogeochem. Cycles s000,14 41), 249-268)
Cleaner paper pulp production Manufacturing of bleached pulp for manufacturing paper products is trending toward use of totally chlorine-free (TCF) bleaching and zero-liquid effluent (ZLE) processes. However, for more widespread deployment of these techniques, there are still several obstacles to overcome. One major challenge in closed-cycle TCF mills is the problem of having to handle lipophilic wood extractives that can accumulate in the circuits. The compounds form the pitch deposits that can lead to low-quality final products and economic losses in mill operations. A. Gutierrez and co-workers evaluated the use of the extractive-degrading fungi Bjerkandera adusta, Phlebia radiata, Pleurotus pulmonarrus, ,nd Poria aubvermispora for removing ththe compounun from Eucalyptus globulus wood using solid-state fermentation conditions. Reeults indicate that levels of problematic compounds can be reduced by up to 75% using fungal pretreatment. Moreover, the potential acute toxicity of black liquors, a waste stream, was significantly reduced. {Environ. Sci. Techno!., this issue, pp. 3735-3709)
Heat and moisture. The authors investigate changing shapes and intensities of warm and cool pockets and the development of cliffs and plateaus at minimum temperatures and compare their findings with similar aspects for Pune City documented in earlier studies. (Deosthali, V "Impact of Rapid Urban Growth on Heat and Moisture Islands in Pune City, India", Atmos. Environ. 2000 34 (17) 27452754) Tropospheric ozone. The authors of this review state that the large-scale increase in tropospheric 0 3 levels is one of the most crucial environmental problems to solve during the coming decades because of its significant consequences for human health and nature. (Guicherit, R.; Roemer, M. "Tropospheric Ozone Trends", Chemosphere: Global Change Sci. 2000, 2 (2), 167-183)
Chemistry Multimicrobial sensor. Two microbial strains with different substrate spectra were immobilized separately within a single biosensor chip featuring four individually addressable platinum electrodes; these were sputtered onto the inner surface of
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four isolated pyramidal "containments" micromachined on a silicon wafer. (Koenig, A., et al. "Multimicrobial Sensor Using Microstructured Three-Dimensional Electrodes Based on Silicon Technology", Anal. Chem. 2000, 72 (9), 2022-2028)
Drinking Water Germany's water. Topics discussed in this review of the drinking water supply situation in Germany include investment and water prices; water consumption changes; water loss in households; endocrine-effective substances in drinking water; N0 3 " in drinking water; and pesticides in drinking water. (Lohse, M.; Dziopak, J. "Aspects of Drinking Water Supply in Germany", Environ. Prot. Eng. 1999,25(4), 11-19) Minimizing DBPs. The concept of the Minimum C102 Dosage (MCDD) is developed to give a clue to the water companies for an optimized C102 dose without compromising the disinfection efficiency. (Schmidt, W, et al. "Minimization of Disinfection By-Products Formation in Water Purification Process Using Chlorine Dioxide—Case Studies", Ozone: Scii Eng. 2000, 22 (2), 215-226)
