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Analysis of satellite-telemetry data mostly occurs long after it has been collected, due to the time and effort needed to collate and interpret such material. Delayed reporting reduces the usefulness of such data for nature conservation where timely information about animal movements is required. To counter this problem, we present a novel approach which combines automated analysis of satellite-telemetry data with rapid communication of insights derived from such data. A relatively simple algorithm (based on radial and angular velocity calculated from fixes) allowed instantaneous detection of excursions away from settlement areas and automated calculation of home ranges on the remaining data. Automating the detection of both excursions and home-range calculations enabled us to disseminate ecological insights from satellite-tag data instantaneously through a dedicated web portal. The automated analysis, interpretation, and communication of satellite-tag and other ecological data offer clear benefits to nature conservation research and practice.  相似文献   
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Gehrke M  Kapila CS  Nam P  Flanigan V 《Chemosphere》2001,43(4-7):479-483
A low-volume, inert sampling and enrichment device for semivolatile organic vapors is described. The device consists of two concentric fused silica capillaries. A small portion of the inter-capillary volume, cooled with a burst of compressed carbon dioxide, serves as a trap for the semivolatile organics. The low mass of the trap permits rapid sampling and desorption cycles suitable for applications requiring fast monitoring of semivolatile chemicals. The device is devoid of switching valves in the sampling train and consequently does not suffer from analyte loss due to irreversible adsorption or interference resulting from cross contamination. The device was successfully used for sampling low concentrations of highly adsorptive nitroaromatic compounds and is applicable for polychlorinated dibenzo-p-dioxins (PCDDs) and polyaromatic hydrocarbons (PAHs).  相似文献   
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An analytical method involving supercritical fluid extraction (SFE) followed by a two-dimensional gas chromatography (2D-GC) analysis was developed to determine the concentration (first GC) and enantiomeric ratio (second GC) of cis- and trans-chlordanes at the ppb (ng/g) level in fish tissue. The SFE method allowed concentration of the compounds of interest, and reduced the number of extraction and sample clean-up manipulations as compared to classical solvent extraction techniques. Four hundred common carp fingerling (Cyprinus carpio, L.) were exposed for three days to water containing 5 ppb (5 ng/g) technical grade chlordane containing about 1 ppb of chlordane isomers. The fish concentrated the pesticides more than 200 times (162 and 312 ng/g of cis- and trans-chlordane, respectively). However, the uptake is not enantioselective. The concentration of the principle constituents and their enantiomeric ratio was followed during a fifty days growth period in chlordane free water. The first order decay of concentration was observed with a half time of about 18 days for both the cis- and trans-chlordane isomers. However it was found that the enantiomeric ratio of the trans-chlordane was significantly altered during this short period of time, decreasing from ER=1 to ER=0.7, while no enantiomeric changes were observed for the cis-chlordane. It seems that the (-)-trans-chlordane is metabolized significantly faster (t(1/2-)=15 days) in the river carp fish than the (+)-trans-enantiomer (t(1/2+)=20 days).  相似文献   
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The survival of certain bacterial cultures suspended in sewage sludge and exposed to gamma-radiation was studied. The inactivation patterns of most of the organisms were significantly different when irradiation was performed using sewage samples collected in the summer and monsoon seasons. The summer sample collected from the anaerobic digestor afforded significant protection to both Gram negative and Gram positive organisms. This was evident by the increase in dose required to bring about a 6 log cycle reduction in viable count of the bacterial cultures, when suspended in sewage samples instead of phosphate buffer. The observations made using monsoon digestor samples were quite different. This sewage sludge greatly enhanced inactivation by gamma-radiation in most cases. The effects of certain chemicals on the inactivation patterns of two organisms-Salmonella typhi and Shigella flexneri-were examined. Arsenate, mercury and lead salts sensitised S. typhi, while barium acetate and sodium sulphide protected this culture against gamma-radiation. In the case of Sh. flexneri, barium acetate and iodacetamide proved to be radioprotectors. The effects of some chemicals on the inactivation pattern of Sh. flexneri cells irradiated in sludge are also discussed.  相似文献   
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Solvent extraction and tandem dechlorination for decontamination of soil   总被引:1,自引:0,他引:1  
The United States Environmental Protection Agency (US EPA) guidelines allow removal of polychlorinated biphenyls (PCBs) from soils via solvent extraction. This option holds promise for removal of other recalcitrant organic contaminants as well. A study was undertaken to evaluate the effectiveness of solvent extraction with two tandem degradation techniques. The degradation techniques were chemical dehalogenation with immobilized reagents and gamma-ray irradiation. The integrated approach was evaluated with contaminated soils from wood treatment and electric power substation sites. Evaluations were carried out on a bench scale in the laboratory and on a semi-pilot scale at a contaminated site. Binary solvent mixture of alkanes and alcohols yielded the highest extraction efficiencies. Extraction efficiencies in excess of 90% were obtained for PCBs, polychlorinated dibenzo-p-dioxins (PCDDs) and polynuclear aromatic hydrocarbons (PAHs). Extracted PCBs were rapidly degraded through chemical dehalogenation or with high doses of the gamma-ray irradiation. The residual organics in the solvent mixture were removed with activated carbon, and the solvent was recycled for subsequent soil extractions. Contaminants adsorbed on the activated carbon were destroyed with a counter flow oxidation process.  相似文献   
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Field and laboratory studies were conducted to investigate the persistence of chlordane in the aquatic and terrestrial environment. The laboratory data show that the transformation and loss of the chlordane constituents is dependent on soil characteristics. The overall rate of loss is also dependent on the depth of application, being significantly lower at greater depths. The field data show a strong correlation between urban development and residue concentration levels.  相似文献   
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A carbon adsorbent obtained by a procedure analogous to reverse burn coal gasification is being evaluated in our laboratory. This low surface area carbon adsorbent shows considerable promise as a fractionation medium for a variety of organics. The performance of the adsorbent compares favorably to the highly specialized carbon adsorbents such as PX-21 (Amoco Corp.). The adsorbent also has considerable potential for treatment of wastes containing organochlorine compounds. The adsorbent shows good adsorption capacity and can hold as much as 50% (w/w basis) of organic sludge while maintaining a relatively dry, granular character. Furthermore, this waste-loaded adsorbent is amenable to highly efficient self-sustained thermal degradation. Degradation efficiencies approaching 99.99 percent have been achieved for such recalcitrant organics as polychlorinated biphenyls and tetrachlorodibenzo-p-dioxins.  相似文献   
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