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751.
Leverage     
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752.
A series of studies examined the effects of labelled meaning on affective response to housing scenes. Students at Ohio State University assessed their feelings towards imagined housing (public or private) and cities (Memphis, Houston and San Francisco). Expected differences in the affective quality were found. Responses to color photographs of specific housing scenes labelled as either private condominiums or public housing were obtained. Differences in scene-affect as a function of labelled meaning were found. Responses to housing scenes labelled as located in either Memphis, Houston or San Francisco revealed no differences in scene-affect as a function of label meaning. This latter finding was confirmed in a non-repeated measure examination. Differences in the fittingness, potency or relevance of the information provided may account for the pattern of findings.  相似文献   
753.
Concentrations of elemental carbon (EC), organic carbon (OC), and 33 organic source markers (12 alkanes, 18 polycyclic aromatic hydrocarbons and ketones, and 3 hopanes) are reported near a highway in Raleigh, NC with an annual average daily traffic count of approximately 125,000 vehicles. Daily samples (24-h) were collected at two locations, one approximately 10 m and the other 275 m perpendicular from the road. Concentrations of OC were similar between near (mean = 7.6 μg m?3) and far (8.0 μg m?3) locations, but concentrations of most organic species at the near site were between 1.5 and 2 times higher than those at the far site.  相似文献   
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Environmental Science and Pollution Research - Vegetated buffer strips (VBSs) are widely encouraged as a cost-effective strategy to address phosphorus (P) pollution associated with agricultural...  相似文献   
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Nonequilibrium disc-flow techniques may better reproduce dynamic soil-pesticide interactions than traditional batch sorption studies. Batch kinetic and equilibrium experiments and dual-label thin-disc flow experiments were conducted with atrazine (6-chloro-N-ethyl-N'-isopropyl-1,3,5-triazine-2,4-diamine) and imazaquin [2-(4,5-dihydro-4-methyl-4-(1-methylethyl)-5-oxo-1H-imidazol-2-yl)-3-quinolinecarboxylic acid] using a Demopolis silt loam (loamy-skeletal, carbonatic, thermic, shallow Typic Udorthent; 8% clay, 62 g kg(-1) organic matter, 7.6 pH). Batch kinetic studies with both herbicides revealed an almost instantaneous rapid phase and a much slower gradual phase. The rapid phase was complete after 5 min and equilibrium was reached at 24 h. The rapid phase accounted for 74% and 12 to 30% of the total amounts adsorbed for atrazine and imazaquin, respectively. The sorption of both the rapid and 24-h isotherms for each herbicide best fit the Freundlich equation. The rapid and 24-h K(f) values of atrazine were 1.38 and 2.41, respectively, and the N value of both phases was approximately 0.93. For imazaquin, the rapid and 24-h K(f) values were 0.056 and 035, respectively, and the N value for the rapid phase of imazaquin was 0.71, compared with 0.86 for the 24-h isotherm. In the dual-label thin-disc flow experiments, the average partition coefficient for atrazine at the peak soil concentration point was 1.54. This value closely agreed with the observed rapid-phase K(f) value of 1.38. In contrast, the thin-disc flow experiments failed to detect any imazaquin retention. The thin-disc flow method can allow for a greater resolution of rapid sorption kinetics, which is impractical with batch studies. Along with dynamic partitioning data, the thin-disc flow method may provide kinetics data that may better complement environmental models than coefficients generated with batch techniques.  相似文献   
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An urban population of ducks in Puyallup, Washington, USA was studied for 14 consecutive months beginning in November 1978. Observations were made weekly from four study sites where ducks would congregate at early morning hours. Factors contributing to the presence of waterfowl in Puyallyup included abundant food supplies and a creek corridor that connected fragmented habitats in the urban area to the larger rural populations of waterfowl. Mallards (Anas platyrhynchos) were the most abundant of the 13 species observed and were the only ducks remaining during the nesting season. Habitat size and complexity were important factors influencing the species diversity of a particular site. Nesting success of mallards was poor due to limited distribution of nesting habitat, intraspecific aggression, and human disturbance. Both site-specific and more broad-based strategies are suggested for managing and planning for duck populations in urban areas.  相似文献   
759.
The concept of mineral consumption is considered in the context of a (metallic) commodity's progression from mine to manufacture and reasons are advanced as to why consumption is best measured at the point referred to as the “first processing stage.” Two methods for measuring consumption at this stage, one direct (“reported consumption”) and one deductive (“apparent consumption”), are described and the merits and drawbacks of the methods discussed. The article concludes with a brief review of the existing statistics on worldwide mineral consumption and suggests that there is the scope, and the need, for improvement. Dans cet article, la notion de la consommation minérale est envisagée dans le cadre de l'acheminement du minerai (métallique) de la mine à l'usine de transformation. II donne les raisons pour lesquelles la consommation peut se mesurer le mieux au niveau de la “phase de première transformation.” A ce stade, l'article décrit deux méthodes permettant de mesurer cette consommation: l'une directe (la consommation déclarée) et l'autre supposée (la consommation apparente). Les avantages et les inconvénients des méthodes y sont aussi discutés. En conclusion, l'article passe brièvement en revue les statistiques existantes sur la consommation minérale mondiale et suggère que la possibilité ainsi que le besoin d'amélioration se font sentir dans ce domaine. El concepto de consumo de minerales se examina dentro del contexto de la progresión del producto desde la mina a la manufactura y se sostiene que dicho consumo se mide mejor en la “etapa de primer procesamiento.” Se describen dos métodos para medir el consumo en esta etapa, el método directo (consumo reportado) y deductivo (consumo aparente). Se discuten las ventajas y desventajas de estos métodos. El artículo concluye con una revisión breve de las estadísticas existentes del consumo de minerales a nivel mundial y sugiere que existe la necesidad y la posibilidad para mejorarlas.  相似文献   
760.
This research demonstrates the contribution of phenomenological inquiry within the realm of geographic and environmental planning. The contention is that a focus on the wide range of individual meanings and values ascribed to landscapes, a marginalized element in many planning assessments, can bring out data to more substantively inform decision making, A case study of user meanings imparted to residual waterfront land in Hoboken, New Jersey, USA, suggests that such property provides an array of amenities to residents. Most importantly, it expands the range of recreational activities, creates visual relief from the monotonous urban milieu, and provides scenic vistas to promote an awareness of the quality of life still possible in cities. The study concludes that planners can use phenomenology to generate data for more judicious decision making.  相似文献   
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