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831.
Anita M. Thompson Kyunghyun Kim Anthony J. Vandermuss 《Journal of the American Water Resources Association》2008,44(5):1325-1336
Abstract: Urban impervious surfaces absorb and store thermal energy, particularly during warm summer months. During a rainfall/runoff event, thermal energy is transferred from the impervious surface to the runoff, causing it to become warmer. As this higher temperature runoff enters receiving waters, it can be harmful to coldwater habitat. In an urban watershed, impervious asphalt surfaces (roads, parking lots, and driveways) and pervious residential lawns comprise a significant portion of the watershed area. A paired asphalt‐turfgrass sod plot was constructed to compare the thermal runoff characteristics between asphalt and turfgrass sod surfaces, to identify meteorological variables that influence these thermal characteristics, and to evaluate evaporative heat loss for runoff from asphalt surfaces. Rainfall simulations were conducted during the summers of 2004 and 2005 under a range of climatic conditions. Asphalt surface temperatures immediately prior to rainfall simulations averaged 43.6°C and decreased an average of 12.3°C over 60 min as rain cooled the surface. In contrast, presimulation sod surface temperatures averaged only 23.3°C and increased an average of 1.3°C throughout the rainfall events. Heat transferred from the asphalt to the runoff resulted in initial asphalt runoff temperatures averaging 35.0°C that decreased by an average of 4.1°C at the end of the event. Sod runoff temperatures averaged only 25.5°C and remained fairly constant throughout the simulations. Multivariable regression equations were developed to predict (1) average asphalt surface temperature (R2 = 0.90) and average asphalt runoff temperature (R2 = 0.92) as a function of solar radiation, rain temperature, and wind speed, and (2) average sod surface temperature (R2 = 0.85) and average sod runoff temperature (R2 = 0.94) as a function of solar radiation, rain temperature, rain intensity, and wind speed. Based on a heat balance analysis, existing evaporation equations developed from studies on lakes were not adequate to predict evaporation from runoff on a heated impervious surface. The combined heat from the asphalt and sod plots was an average of 38% less than the total heat had the total area consisted solely of asphalt. 相似文献
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The use of science to inform and underpin decision-making on natural resources is not self-evident as stakeholders often use science in a selective and strategic way. Scientific analyses of science utilisation often focus on how the science–policy interface is organised and from this perspective provide recommendations to scientists about how they can increase their contribution to decision-making. Yet in this paper we argue that a wider perspective on the science–policy interface, in particular by analysing the roles and interactions of actors other than those directly involved, provides both additional explanations and new points of application for strategies aimed at enhancing science utilisation. We illustrate our claim by means of an analysis of decision-making on cockle fisheries and gas mining in the Dutch Wadden Sea between the 1990s and 2004. For many years, scientific studies addressing the ecological effects of these activities were not used to meaningfully contribute to decision-making. In 2004 this situation changed radically. Explanations include the role of intermediaries between scientists, stakeholders and decision-makers and new legislation. Scientists could enhance the chances of knowledge utilisation both by creating a more open science–policy interface and by reframing the policy problems at issue. 相似文献
834.
Sun-Kwon Kim Hye-Sung Won Shin Wha Lee Jeong Kon Kim Jae-Yoon Shim Pil Ryang Lee Ahm Kim 《黑龙江环境通报》2006,26(2):171-174
Congenital epulis is a benign intraoral tumor that has rarely been diagnosed prenatally. We report a fetus with congenital epulis diagnosed by three-dimensional (3-D) ultrasound and fetal magnetic resonance imaging (MRI) at 35 weeks' gestation. We show an image of congenital epulis using a new ultrasound technique, the 3-D multislice view, which shows images similar to CT or MRI. This is a short case report of congenital epulis diagnosed prenatally by 3-D ultrasound using multislice view and MRI. Copyright © 2006 John Wiley & Sons, Ltd. 相似文献
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Summary. Individual variations in pheromone emission patterns were examined in a scarab beetle, Anomala cuprea Hope (Coleoptera: Scarabaeidae), by headspace collection of airborne volatiles from individual females. The amount of pheromone
obtained varied among virgin females, and about 16% of these females (“silent” females) did not emit detectable amount of
pheromone throughout the experimental period. There was no clear temporal pattern of peak pheromone emission for 19 days after
the onset. More than half of the laboratory mated females completely stopped releasing pheromone after the first mating, while
the rest of them continued releasing pheromone, frequently followed by additional mating.
Received 26 March 2001; accepted 28 January 2002. 相似文献
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