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81.
Traffic related platinum deposits on, or near to, the roads. Platinum accumulation was studied using the method of standardised culture of grass (Lolium multiflorum) at locations with different traffic exposure in the region of Munich. Grass cultures from 6 locations with high traffic exposure, and 3 reference locations far away from traffic emissions, were analysed in 1992 and 1993. The results show a good indication of the platinum emissions byLolium multiflorum. The platinum concentrations rose with the increasing traffic. They diminished with growing distance from the verge of the road. The highest average platinum concentrations were measured at locations close to highly frequented urban roads, in the range 0.8 to 2.9 μg/kg dm. The average platinum concentration at locations far from emissions was found in the range of 0.17 to 0.51 μg/kg dm in 1992 and 1993. The good correlation between the platinum concentrations in grass cultures and the concentrations of other traffic-related elements, like antimony, chromium and lead, verifies the dependence of platinum accumulation from traffic. 相似文献
82.
Wing Cheong Leung David Chitayat Gareth Seaward Rory Windrim Greg Ryan Jon Barrett Elizabeth J. T. Winsor 《黑龙江环境通报》2001,21(4):327-332
We retrospectively reviewed 309 amniotic fluid interphase fluorescence in situ hybridization (FISH) analyses performed from October 1995 to June 1999 to assess the role of interphase FISH in the management of patients at increased risk for fetal aneuploidies. Gestational age and indications for amniocentesis, clinical interventions after FISH results, as well as interventions after final culture reports were analyzed. There were 244 (79%) normal, 50 (16%) abnormal and 15 (5%) inconclusive FISH results. There were no false-positive or false-negative results, but there were nine (3%) clinically significant chromosomal abnormalities not detectable by FISH. Of the 50 women with abnormal FISH results, 26 (52%) elected to terminate the pregnancy prior to the availability of the standard chromosome analysis. In two of the fetuses with trisomy 21 no abnormalities were reported by ultrasound examination. Our experience indicates that interphase FISH results played an important role in decision making, especially for pregnancies close to 24 weeks' gestation. Standard karyotype analysis is still required for detection of chromosome abnormalities not detectable by interphase FISH techniques and for clarification of unusual or inconclusive FISH results. Copyright © 2001 John Wiley & Sons, Ltd. 相似文献
83.
Ludwig Peichl 《Environmental Sciences Europe》1997,9(5):273-282
The working group on “boindication/assessment of effects” is made up of specialists active in the fields of bioindication and emission ecology for the German Federal administrative offices concerned with the protection of the environment and for the Geman Environmental Protection Agency. In April 1996, this working group adopted the recommendation for a “countrywide survey on the effects of emissions using bioindicatiors”. The goal of this national survey is to determine the geographic distribution and the development over time of such emissions, as well as to document the effects of background emissions. In order to achieve these goals, the development of national measuring networks and permanent observation stations is mandatory. A minimal demand of investigations and of investigative procedures is required in order to compare the results of the individual Federal States and to consequently combine these findings as an overall picture for the entire Federal Republic of Germany. Mosses and lichens are recommended for passive biological monitoring, while standardized grass cultures, kale, stinging nettle and tobacco are suggested for active biomonitoring. In addition, detailed methodical recommendations concerning the use of standardized grass cultures and kale are discussed. 相似文献
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Three types of soil-gas surveys were performed over the same location at an industrial facility. The surveys performed were (1) a passive technique using buried collectors, (2) an active technique in which samples were collected in the field by pumping with subsequent analysis at a field laboratory, and (3) a screening technique that employed a hand-held survey instrument. Each of the surveys had desirable features, but there was considerable variability in the quality of data obtained, cost, and ease of performance. The passive and active surveys provided excellent detection limits, but the passive technique does not provide data in real time. The active survey was also time-consuming and required an analytical chemist in the field. Neither the active nor the passive survey were able to delineate the plume of contaminated groundwater. Consequently, the results from the rapid and inexpensive reconnaissance technique provided functionally equivalent data.Publication No. 3672, Environmental Sciences Division, ORNL.Operated by Martin Marietta Energy Systems, Inc. for the U.S. Department of Energy under Contract No. DE-AC05-840R21400. 相似文献
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Ludwig Drechsel 《Die Naturwissenschaften》1957,44(20):533-533