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971.
Matthaios P. Kavvalakis Manolis N. Tzatzarakis Eleftheria P. Theodoropoulou Emmanouil G. Barbounis Andreas K. Tsakalof Aristidis M. Tsatsakis 《Chemosphere》2013
Imidacloprid (IMI) is a relatively new neuro-active neonicotinoid insecticide and nowadays one of the largest selling insecticides worldwide. In the present study a LC–APCI–MS based method was developed and validated for the quantification of imidacloprid and its main metabolite 6-chloronicotinic acid (6-CINA) in urine and hair specimens. The method was tested in biomonitoring of intentionally exposed animals and subsequently applied for biomonitoring of Cretan urban and rural population. 相似文献
972.
973.
Sapna Johnson Dipankar Patra P. Dureja 《Journal of environmental science and health. Part. B》2013,48(4):491-501
Abstract Azadirachtin‐A on exposure to UV‐light (254 nm) as a thin film on glass surface gave a isomerised (Z)‐2‐ methylbut‐2‐enoate product. Half‐life of azadirachtin‐A as thin film under UV light was found to be 48 min. Azadirachtin ‐A was irradiated along with saturated and unsaturated fatty acids, and fatty oils under ultra‐violet light as thin film. Saturated fatty acid increased the rate of photodegradation of azadirachtin‐A, whereas unsaturated fatty acids such as oleic, linoleic and elaidic acid reduced the rate of degradation. Castor, linseed and olive oil accelerated the rate of degradation, whereas neem oil showed no or little change in the rate of degradation of azadirachtin‐A. None of these fatty acids and fatty oils were effective in controlling the rate of degradation of azadirachtin‐A under UV‐light as thin film. 相似文献
974.
Charles E. Billings Leslie Silverman Richard Dennis Lester H. Levenbaum 《Journal of the Air & Waste Management Association (1995)》2013,63(4):318-330
The trends in and relationships between ambient air concentrations of sulfur dioxide and sulfate aerosols at 48 urban sites and 27 nonurban sites throughout the U.S. between 1963 and 1972 have been analyzed. The substantial decreases in ambient SO2 concentrations measured at urban sites in the eastern and midwestern U.S. are consistent with the corresponding reductions in local SO2 emissions, but these decreases have been accompanied by only modest decreases in ambient sulfate concentrations. Large differences in the amounts of SO2 emitted within individual air quality control regions are associated with much smaller differences in the corresponding ambient sulfate concentrations. Substantial changes in the patterns of SO2 emissions between air quality regions result in essentially no differences between ambient sulfate concentrations in those air quality regions. Comparisons of several air quality regions in the eastern and western U.S. with similar SO2 emission levels and patterns of emissions clearly demonstrates the higher ambient sulfate concentration levels in eastern air quality control regions. Relationships between SO2, sulfates, and vanadium concentrations at eastern nonurban U.S. sites cannot be explained by local emission sources. These various observed results can be best explained by long distance sulfur oxide transport with chemical conversion of SO2 to sulfates occurring over ranges of hundreds of kilometers. This conclusion has been suggested earlier and the present analysis strongly supports previous discussions. An impact of long range transport of sulfates is to emphasize the need for Consistent strategies for reduction of sulfur oxides throughout large geographical regions. Additions of large capacities involving elevated sources in mid-continental or western regions could result in significant increases in sulfate concentrations well downwind of such sources. Some of the types of research activities required to quantitate crucial experimental parameters are discussed. 相似文献
975.
Previous attempts to measure heavy metals in air are discussed with particular reference to lead. A polarographic method was developed for lead in air samples taken on glass fiber sheet. Using this method, the distribution of lead across the glass fiber sheet was investigated, and within experimental error, found to be uniform. Air samples from 18 Ontario cities, previously analyzed for benzo [a]pyrene content were analyzed. 相似文献
976.
Charles S. Maneri P. E. William H. Megonnell P. E. 《Journal of the Air & Waste Management Association (1995)》2013,63(5):374-377
The proposed By-law changes have been suggested over the last two years. They are basically housekeeping changes which correct the language, eliminate duplications, and clarify the dates for the receipt and acceptance of the ballots for nominees for the Board. The major revision proposed is in Article XV of the Technical Council which was necessitated by the new structure of the Technical Council approved by the Board of Directors in June 1970. 相似文献
977.
978.
979.
An addition of additives to fuel oils prior to combustion is one way of reducing combustible contaminant emissions to the outer air. Reported test results show that some additives improve, moderately, the combustive properties of fuel oils. Combustion is also improved but to a lesser degree, in boiler systems that are deficient in operation and design. Being combustible, polynuclear hydrocarbons emissions would be reduced by use of additives. Other types of additives to reduce slagging and inhibit corrosion from combustion of fuel oils are also available. The cost of using additives is low. Improved additives are required, especially ones to better combustion in the deficient boiler systems. These can be found by research and literature surveys. Their effectiveness and nontoxicity would be confirmed by laboratory and field testing. 相似文献
980.