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281.
In the Republic of Bénin, aquatic ecosystems are subject to poisoning risks due to the inappropriate use of pesticides, such as washing of empty bottles in rivers and using pesticides to catch fish. In some areas, cotton fields are located near riverbanks, increasing the probability of pesticide emission to the river. To assess contamination levels in the Ouémé River catchment area, different fish species were collected from different geographical areas along the river. DDT, its metabolites and isomers were the most frequently identified pesticides in fish flesh, alpha-endosulfan, beta-endosulfan, dieldrin, telodrin, lindane and octachlorostyrene were also detected. Concentrations of pesticide residues in fish ranged from 0 to 1364 ng/g lipid. A preliminary risk assessment indicated that the daily intake of chlorinated pesticides by people consuming fish from the Ouémé River still is rather low and does not present an immediate risk.  相似文献   
282.
Environmental Science and Pollution Research - The studies presented in this work show that solid tannery waste-like shavings can be used as high-protein materials for fertilizer production...  相似文献   
283.
Winter deicers are a major source of chloride contamination to shallow aquifers in northern latitudes. In the greater Chicago area of northeast Illinois, chloride has been accumulating for decades and in many places now exceeds the United States Environmental Protection Agency secondary standard of 250 mg/L. MODFLOW-NWT and MT3D-USGS were used to simulate the accumulation of chloride with 30 years of data in the shallow aquifer of Will County in northeast Illinois. This aquifer is composed of unconsolidated sediments, largely from glacial deposits, overlying a fractured dolomite bedrock. To calibrate to observed heads and chloride, the model needed refined geologic features, higher chloride concentrations on cells representing commercial or industrial lands, lower chloride concentrations on cells representing roads, and point source areas to speed chloride's emergence in the aquifer. These point sources are locally significant and could represent different anthropogenic or geologic features, such as municipal stormwater infrastructure. Future simulations indicate that chloride is not at steady state in the shallow aquifer and wells are at risk of exceeding the secondary standard if winter deicing applications are not reduced. It may take decades for the full impacts of reduced deicing rates to be observed in wells, owing to the long residence time of water in the aquifer. This transient model calibration was possible because of the 30-year dataset collected by communities and government agencies.  相似文献   
284.

Introduction

This article describes one experiment that studied the influence of Daytime Running Lamps (DRL) on pedestrian detection of turn indicators.

Method

An experimental device including one DRL and one turn indicator was used in order to determine Visual Reaction Times (VRT) of 148 observers in different situations involving turn indicator activation. Such situations were combinations of three main variables: color of DRL, separation between DRL and Turn Indicator, and observation angle.

Results

Significant changes in VRT were found depending on the configurations above, especially the observation angle and the color of DRL. This second result demonstrates that amber DRLs inhibit the detection of Turn Indicators.

Impact on industry

One of the main targets of this paper is to recommend that carmakers introduce only white DRLs on new vehicles. We also intend to advise regulatory bodies working on automotive regulation about the consequences of allowing amber DRLs and also about the danger of introducing constrains on the distance between DRL and Turn Indicator without further experimental evidences.  相似文献   
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