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751.
Environmental Science and Pollution Research - Sharks are top predators and play an important role in the regulation of marine ecosystems at lower trophic position. Mustelus californicus, Sphyrna...  相似文献   
752.
Environmental Science and Pollution Research - This study investigated the occurrence of selected metals and metalloids (As, Cd, Cr, Cu, Hg, Ni, Pb, Zn) in radio-dated sediment cores from a coastal...  相似文献   
753.
Using geographic information system, soil sampling, and statistical analysis to map anthropogenic effects on soil  相似文献   
754.
Environmental investigations have been conducted at 23 military firing ranges in the United States and Canada. The specific training facilities most frequently evaluated were hand grenade, antitank rocket, and artillery ranges. Energetic compounds (explosives and propellants) were determined and linked to the type of munition used and the major mechanisms of deposition.  相似文献   
755.
The association between cerium status and risk of first acute myocardial infarction (AMI) was examined in a case-control study in 10 centres from Europe and Israel. Cerium in toenails was assessed by neutron activation analysis in 684 cases and 724 controls aged 70 years or younger. Mean concentrations of cerium were 186 and 173 microg/kg in cases and controls, respectively. Cerium was positively associated with low socio-economic status, smoking, mercury, zinc and scandium (p0.001). Cases had significantly higher levels of cerium than controls after adjustment for age and centre (case-control ratio 1.074; 95% CI 1.002-1.151) and increased in further adjustment for other cardiovascular risk factors 1.085; 95% CI 1.025-1.149. The risk after adjustment for age and centre was higher with increasing cerium levels (p for trend=0.02). After adjustment for BMI, history of hypertension, smoking, alcohol intake, diabetes, family history of CHD, beta-carotene, lycopene, alpha-tocopherol, selenium, mercury and scandium, the OR for the highest quintile was 1.43 (95% CI 0.85-2.41; p-trend 0.08). When we applied this same model in non-smokers the odds ratios in the 4th and 5th quintiles of cerium as compared with the lowest were 2.09 (95% CI 1.05-4.16) and 2.81 (95% CI 1.21-6.52), respectively, p-trend 0.011. Our results suggest that toenail cerium levels may be associated with an increased risk of AMI, but more research is warranted to shed further light and fully understand the plausibility and public health implications of these findings.  相似文献   
756.
Hydrodynamic cavitation (HC)-based treatments have been proposed for the degradation of phenol as a toxic pollutant. The present work aimed to optimize the degradation of phenol using HC by means of Doehlert experimental design, which has not been previously addressed. Initially, operational parameters of hydraulic characteristics of the pump, inlet pressure, solution pH, and initial concentration were optimized; later, the effects of pH solution and H2O2 loading or initial pollutant concentration on phenol degradation were explored using the Doehlert experimental design. It was observed that phenol degradation is strongly dependent on the pH of the solution. Also, the acidic condition favors the formation of hydroxyl radicals and thus, the degradation of phenol. Based on the Doehlert matrix, the 94.1% phenol degradation and 68.60% total organic carbon (TOC) were obtained in 180 min at 304.5 mg/L of hydrogen peroxide at an initial concentration of 20 mg/L, 2.0 pH, and 90 psi inlet pressure, providing a cavitational yield of 6.33 × 10−6 mg/J and minimum treatment cost of US$/L 0.13. Overall, it has been observed that HC can be a promising route for the removal of pollutants (phenol) effectively using hydrogen peroxide as an additive.  相似文献   
757.

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   
758.
Environmental Science and Pollution Research - Catalyst samples based on SiO2-supported TiO2 were prepared with the incorporation of Ag (metal), S (nonmetal), and ZnO@S (semiconductor and...  相似文献   
759.
Environmental Science and Pollution Research - In this study, we evaluated indoor air quality to highlight the effects of environmental pollution in the field of cultural heritage. In particular,...  相似文献   
760.
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