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161.
Due to its resistance to many wastewater treatment processes, the antiepileptic drug carbamazepine (CBZ) is routinely found in wastewater effluent. Wastewater irrigation is an alternative to stream discharge of wastewater effluent, which utilizes the soil as a tertiary filter to remove excess nutrients and has the potential to remove pharmaceutical compounds. Previous data suggest that CBZ is strongly sorbed to soil; however, it is unknown what its fate is for long periods of irrigation and if land use affects its distribution. Therefore, the objectives of our research were to characterize CBZ concentrations in soils that have been receiving wastewater irrigation for >25 yr under three different land uses: cropped, grassed, and forested. Triplicate soil cores were collected at each of the land uses to a depth of 120 cm. Extractions for CBZ were performed using 5-g soil samples and 20 mL of acetonitrile. The extracted solutions were analyzed on a liquid chromatograph tandem mass spectrometer. The samples were also analyzed for supporting information such as organic carbon, pH, and electrical conductivity. Results suggest that there is accumulation of the CBZ in the surface soils, which have the highest organic carbon content. Average concentrations of CBZ in the surface soils were 4.92, 2.9, and 1.92 ng g, for the forested, grassed, and cropped land uses, respectively. The majority of the CBZ was found in the upper 30 cm of the profile. Our results suggest that the soils adsorb CBZ and slow its movement into groundwater, compared to the movement of nonadsorbed chemicals.  相似文献   
162.
The applicability of a mature compost as a soil amendment to promote the growth of native species for the phytorestoration of a mine-affected soil from a semi-arid area (SE Spain), contaminated with trace elements (As, Cd, Cu, Mn, Pb and Zn), was evaluated in a 2-year field experiment. The effects of an inorganic fertiliser were also determined for comparison. Bituminaria bituminosa was the selected native plant since it is a leguminous species adapted to the particular local pedoclimatic conditions. Compost addition increased total organic-C concentrations in soil with respect to the control and fertiliser treatments, maintained elevated available P concentrations throughout the duration of the experiment and stimulated soil microbial biomass, while trace elements extractability in the soil was rather low due to the calcareous nature of the soil and almost unaltered in the different treatments. Tissue concentrations of P and K in B. bituminosa increased after the addition of compost, associated with growth stimulation. Leaf Cu concentration was also increased by the amendments, although overall the trace elements concentrations can be considered non-toxic. In addition, the spontaneous colonisation of the plots by a total of 29 species of 15 different families at the end of the experiment produced a greater vegetation cover, especially in plots amended with compost. Therefore, the use of compost as a soil amendment appears to be useful for the promotion of a vegetation cover and the phytostabilisation of moderately contaminated soils under semi-arid conditions.  相似文献   
163.
The interaction of a typical flue gas with active charcoal and bituminous coal char at temperatures between 600 and 800°C and atmospheric pressure has been studied. The SO2 in the flue gas interacts with the carbon to form primarily H2S, COS, and a carbon-sulfur surface complex. H2S and COS break through the carbon bed much in advance of SO2. At 800°C, sulfur retention on the bed exceeds at least 11% before SO2 breakthrough occurs. The reaction of H2S and COS with O2 over active charcoal at 100–140°C to produce sulfur, which deposits on the carbon, has also been studied and found to be feasible. As a result of this study, a new process is outlined for the removal of SO2 from flue gas, with the ultimate conversion  相似文献   
164.
The following paper was presented by Alan B. Walker at the International Conference on Electrostatic Precipitation held in Monterey, California, October 14–16, 1981. Mr. Walker’s candid remarks were part of the opening session on “Electrostatic Precipitation Today.” The proceedings of this outstanding conference will be published by the Air Pollution Control Association.  相似文献   
165.
Steady state kinetic models, which may be useful for the prediction from simple data, of the bioaccumulation of liophilic pollutants in ecosystems are discussed. For some aquatic species, such as Mytilus edulis, bioconcentration factors (BCFs) are closely related to water solubilities, and octanol: water partition coefficients (Kows). In other cases, more complex models are necessary to take account of metabolism and/or uptake from food. Somewhat different considerations apply in the estimation of bioaccumulation factors (BFs) for terrestrial organisms that cannot excrete lipophilic compounds by diffusion into ambient water. The relationship between half-lives and BFs is discussed. Metabolism is necessary for the effective elimination of lipophilic pollutants by terrestrial animals, and a model is proposed for the prediction of BFs from kinetic data obtained from in vitro metabolism studies. If such a model can be successfully developed it will make possible the prediction of bioaccumulation of pollutants by a wide range of species which cannot be studied by present methods.  相似文献   
166.
The need for ambient gaseous ammonia (NH(3)) measurements has increased in the last decade as reactive NH(3) concentrations and deposition fluxes show little change even with tightening standards on nitrogen oxides (NO(x)) emissions. Currently, there are several networks developing methods for adding NH(3) measurements in the U.S. Gaseous NH(3) measurements will provide scientists and policymakers data which can be used to estimate ecosystem inputs, validate air quality models including trends and regional variability, and evaluate changes to the environment based on additional emission reduction requirements and estimates of critical nitrogen load exceedances. The passive samplers described in this paper were deployed in duplicate or triplicate and collocated with annular denuders or continuous instruments to determine their accuracy. The samplers assessed included the Adapted Low-Cost Passive High Absorption (ALPHA), Radiello(?), and Ogawa passive samplers. The median relative percent differences (MRPD) between the reference method and passive samplers for the ALPHA, Radiello(?) and Ogawa were -2.4%, -37% and -44%, respectively. The precision between duplicate samplers for the ALPHA and Ogawa samplers, was 7% and 6%, respectively. Triplicate Radiello(?) precision was assessed using the coefficient of variation (CV). The CV for the Radiello(?) samplers was 10%. This article discusses the statistical results from these studies.  相似文献   
167.
以井冈山风景名胜区作为案例地,基于价值共创理论,运用大数据分析与内容分析方法,收集并分析马蜂窝网站上井冈山景区的游记文本,构建红色旅游资源开发的价值共创机制:以历史文化遗产、自然景观资源和标志性景观符号为资源基础,游客通过红色文化体验、学习培训活动、解说服务体验和自然景观体验等实践活动,获得对红色历史文化的认知、情感的联结和价值观的塑造。另外,红色旅游景区现有的价值共创实践仍旧有限,红色旅游资源开发价值共创机制整合了游客需求、景区支持以及可能存在的价值共创实践,对创新红色旅游资源开发利用手段与产业转型升级具有实践意义。  相似文献   
168.
169.
Environmental Science and Pollution Research - Air toxics are airborne pollutants known or suspected to cause cancer or other serious health effects, including certain volatile organic compounds...  相似文献   
170.
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