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61.
Employees generally rate their performance more favorably than do their supervisors, which can lead to conflict and poor job performance. However, comparative international research indicates that persons from other‐oriented collectivist cultures are less self‐enhancing, suggesting that other‐oriented employees will exhibit greater agreement with ratings provided by their supervisors. We examined the effect of subordinates' other orientation on self‐supervisor performance rating agreement. Consistent with cultural expectations, self‐ratings of other‐oriented subordinates showed greater agreement with ratings provided by their supervisors and less leniency relative to their supervisors' evaluations. These findings have implications for understanding how employees in different professions, organizations, and cultures utilize feedback from their supervisors. Copyright © 2004 John Wiley & Sons, Ltd.  相似文献   
62.
ABSTRACT: Volusia County, in east central Florida, comprises approximately 1,200 square miles situated between the St. Johns River and the Atlantic Ocean. Most of the County is underlain by a three-aquifer system. Population centers in Volusia County, which create a large water demand, are located near the coast. Saltwater intrusion into the ground water near these population centers has led to relocation of public water supply wells further inland. Regional management of the county's water resources commissioned construction of a three-dimensional computer model of the county. Predevelopment simulation results were used as initial conditions for the development simulations, which included well discharge data. The predevelopment model calibration consisted of reproducing field-determined potentiometric surfaces. As part of the calibration process, sensitivity analyses were performed on boundary conditions, recharge rates, permeability, and leakage properties. Results of the model study indicate the utility of computer models as a management tool for the complex ground-water system in Volusia County.  相似文献   
63.
The role of a roadside windbreak of white pine trees in modifying the dispersion of vehicular lead emissions was evaluated. The lead content of foliage and twigs of various ages adjacent to and far from the road was analyzed by atomic absorption spectrophotometry. The lead burden of older needles and twigs was consistently greater than that of younger organs, and was greater in samples taken adjacent to than far from the road. The pattern of lead accumulation on mature needles, but not twigs, varied with precipitation prior to sampling. Twigs retained particles more effectively than needles throughout the season; twigs retained about 115% more lead as µg g-1 and about 2050% more lead as µg cm-2 than similarly located needles. The lead content of soil beneath the windbreak was compared with that of an adjacent, undisturbed field to assess whether the presence Of the windbreak resulted in lead enrichment of the underlying soil. The soil between the curb and the windbreak contained about 50% more lead than that of the field at a similar distance from the road. Within the windbreak, the soil contained about twice the lead content of the soil in the open field at a similar distance from the curb. Windbreaks function as sinks for vehicular lead emissions and thus decrease their dispersion from roads.  相似文献   
64.
Exhibition     
The objective of this critical review is to evaluate and summarize the literature on economic tools used to improve environmental decision making. Environmental decisions are complicated by pervasive uncertainty, and the lack of consensus on goals and on tradeoffs, such as air versus water pollution and versus loss of coal mining jobs. Five decision frameworks are used by regulatory agencies to simplify decision making. Congress’ choice of a decision framework designates the amount of data and analysis that will be required and the range and depth of social values that must be considered. Economic incentives have worked well for phasing out lead in gasoline, for increasing recycling and for reducing the volume of municipal solid waste. Congress has mandated incentives for acid rain and CFCs, and several countries have implemented carbon taxes to abate greenhouse gas emissions. Economic tools have become more central to the analysis and implementation of environmental policies; their role should continue to increase. We conclude that economic tools are extremely valuable, although their application is difficult.  相似文献   
65.
ABSTRACT

This paper discusses the legal and scientific reasons for separating personal exposure to PM into ambient and nonambient components. It then demonstrates by several examples how well-established models and data typically obtained in exposure field studies can be used to estimate both individual and community average exposure to ambient-generated PM (ambient PM outdoors plus ambient PM that has infiltrated indoors), indoor-generated PM, and personal activity PM. Ambient concentrations are not highly correlated with personal exposure to nonambient PM or total PM but are highly correlated with personal exposure to ambient-generated PM. Therefore, ambient concentrations may be used in epidemiology as an appropriate surrogate for personal exposure to ambient-generated PM. Suggestions are offered as to how exposure to ambient-generated PM may be obtained and used in epidemiology and risk assessment.  相似文献   
66.
Pharmaceutical substances have been detected in sewage effluents as well as receiving waters in many parts of the world. In this study, the occurrence and removal of a number of drug compounds were studied within a large sewage treatment plant in the south of England. Samples were processed using solid phase extraction and analysed using gas chromatography-mass spectrometry (GC-MS). The results demonstrate that ibuprofen, paracetamol, salbutamol and mefenamic acid were present in both the influent and effluent of the works while propranolol-HCl was not found above the limit of quantification in any sample. Elimination rates were circa 90% for each compound but several hundred nanograms per litre were still present in the final effluent.  相似文献   
67.
Soil water repellency in golf putting greens may induce preferential "finger flow," leading to enhanced leaching of surface applied fungicides. We examined the effects of root zone composition, treatment with a non-ionic surfactant, and the use of the fungicide iprodion or a combination of azoxystrobin and propiconazole on soil water repellency, soil water content distributions, fungicide leaching, and turf quality during 1 yr. Soil water repellency was measured using the water drop penetration time (WDPT) test and tension infiltrometers. Our study was made on a 3-yr-old experimental green seeded with creeping bentgrass (Agrostis stolonifera L.) 'Penn A-4' at Landvik in southeast Norway. The facility consists of 16 lysimeters with two different root zone materials: (i) straight sand (1% gravel, 96% sand, 3% silt and clay, 4 g kg(-1) organic matter) (SS) and (ii) straight sand mixed with garden compost to an organic matter content of 21 g kg(-1) (Green Mix [GM]). Surfactant treatment resulted in 96% lower average WDPTs at 1 cm depth, three times higher water infiltration rates at the soil surface, and reduced spatial variation in soil water contents. Fungicide leaching was close to zero for the GM lysimeters probably due to stronger sorption. Concentrations in the drainage water from SS lysimeters often exceeded surface water guideline values for all three fungicides, but surfactant treatment dramatically reduced fungicide leaching from these lysimeters. In autumn and winter, surfactant-treated plots were more infected with fungal diseases probably because of higher water content in the turfgrass thatch layer.  相似文献   
68.
Leaching of chromated copper arsenate wood preservatives: a review   总被引:13,自引:0,他引:13  
Recent studies have generated conflicting data regarding the bioaccumulation and toxicity of leachates from preservative-treated wood. Due to the scale of the wood preserving industry, timber treated with the most common preservative, chromated copper arsenate (CCA), may form a significant source of metals in the aquatic environment. The existing literature on leaching of CCA is reviewed, and the numerous factors affecting leaching rates, including pH, salinity, treatment and leaching test protocols are discussed. It is concluded from the literature that insufficient data exists regarding these effects to allow accurate quantification of leaching rates, and also highlights the need for standardised leaching protocols.  相似文献   
69.
地下水位下降,气温上升,水土流失和沙漠化,可能导致粮食价格的上涨.翻倍的谷物价格能够扰乱全球的经济发展,而且这也必然成为世界觉醒的召唤.从这一点看问题就很清楚:A方针--惯常的所做所为--再也不能继续下去了.B方针的3个原则构成是:提高全球水的生产率;中止人口增长;降低碳的排放以稳定气候.  相似文献   
70.
In areas which are highly urbanised, where water re-use is frequently necessary, the importance of “heavy metal” removal during sewage treatment cannot be overestimated. One critical factor controlling the forms of the metals in the sewage is the chemical matrix of the sewage; as a consequence of their chelating capacity detergent builders are important in modifying the sewage matrix. Laboratory simulations of the activated sludge process have been studied to estimate the impact of the detergent builder zeolite type A on the removal of heavy metals from sewage in this treatment process.Experiments have also been undertaken in which the influent concentrations of the builder were doubled, in an endevour to simulate the effect of a “wash day”. It is apparent from the data presented that under conditions of constant loading, zeolite type A did not significantly affect the concentrations of any of the metals studied with the exception of zinc. However, removal of some of the metals was less than in the presence of a condensed phosphate solution. Under conditions of shock loading the improvement in metal removal which has been observed when condensed phosphates were added under conditions o of variable loading was not observed when zeolite type A was added under similar conditions.  相似文献   
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