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481.
Donald D. Davis John M. Skelly 《Journal of the Air & Waste Management Association (1995)》2013,63(3):309-322
Abstract The impact of weather on air pollution was examined and evaluated for the city of Athens, Greece. We used an objectively defined synoptic classification scheme consisting of six summer and eight winter circulation types. This scheme was established using a combination of both factor and cluster analysis during 1954–1999. Surface and isobaric levels of 850 hPa data were used. Factor analysis combined with cluster analysis was used to derive circulation types based on surface meteorological data for the period 1954–1999 in Athens and on surface pressure grid data. The city was divided into three sectors according to the financial and social activities of the residents. To examine the spatial characteristics of pollutant concentrations over Athens for each synoptic type, the synoptic circulation types were then correlated with both gaseous and particulate pollutant concentrations measured in each sector between 1983 and 1999. Finally, extreme and severe episodic events were studied in terms of their meteorological and synoptic characteristics. 相似文献
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Stefan Franz Nemec Ursula Nemec Peter C. Brugger Dieter Bettelheim Siegfried Rotmensch John M. Graham Jr. David L. Rimoin Daniela Prayer 《黑龙江环境通报》2012,32(3):205-213
Magnetic resonance imaging (MRI) appears to be increasingly used, in addition to standard ultrasonography for the diagnosis of abnormalities in utero. Previous studies have recently drawn attention to the technical refinement of MRI to visualize the fetal bones and muscles. Beyond commonly used T2-weighted MRI, echoplanar, thick-slab T2-weighted and dynamic sequences, and three-dimensional MRI techniques, are about to provide new imaging insights into the normal and the pathological musculoskeletal system of the fetus. This review emphasizes the potential significance of MRI in the visualization of the fetal musculoskeletal system. © 2012 John Wiley & Sons, Ltd. 相似文献
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Darryl J. Keith Dave Colton Harry Louft John Lindsay Lance Stewart 《Environmental monitoring and assessment》1999,54(3):259-282
The Underwater Radiation Spectral Identification System (URSIS) is a portable spectrometer used for the in situ detection of radioactivity in the marine environment. This paper reports on the first time application of this technology to assess, in a preliminary manner, the potential radiation threat to the public and environment at an aquatic disposal site – the Massachusetts Bay Industrial Waste Site (IWS). Utilizing the meneuvering capabilities of ROV and manned submersible vehicles, the URSIS was successfully positioned close (5–10 cm) to waste containers for a period sufficient to detect, in real time, the presence of radioactive materials. Spectral data from 45 individual targets indicated that the radionuclides present in sediments which draped or partially buried waste containers were consistent with natural background concentrations. No man-made radionuclides were detected at any of the target or background measurement locations. These data support the conclusion that low-level radiation does not pose an imminent and widespread human health or ecological threat in Massachusetts Bay. 相似文献
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John C. Brower 《Natural resources forum》1979,3(3):263-279
Although the small-scale mining sector in Bolivia has absorbed economic aid, little or no improvement has resulted. It appears that much closer technical and financial co-operation with those operating small mines is called for, including rigid credit supervision. Problems in small-scale mines arise from difficult mining conditions, the tax structure and capital market situation as well as the employment patterns of the mine operators. It is suggested that mechanized projects may not always be the best way to overcome poor conditions, but where they are, lack of collateral is frequently an obstacle. In such cases, a three stage approach to project implementation is proposed. 相似文献
488.
John Powell 《Journal of Environmental Planning and Management》2000,43(3):351-367
A life cycle inventory model was applied to a range of waste management scenarios in the waste collection authorities of Gloucestershire. The life cycle model and the results of modelling different waste management options are described. Model results were submitted to waste managers in the six authorities and utilization of the information was analysed. Analysis suggests that a range of factors arising from both model implementation and the local policy context affects the form and extent of utilization. Increased levels of environmental knowledge and understanding will be required to make effective use of life cycle analysis in local authority decision making. 相似文献
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