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941.

Background  

The Atacama Desert in Northern Chile is one of the most arid places on earth. However, fog occurs regularly at the coastal mountain range and can be collected at different sites in Chile to supply settlements at the coast with freshwater. This is also planned in the fog oasis Alto Patache (20°49′S, 70°09′W). For this pilot study, we collected fog water samples in July and August 2008 for chemical analysis to find indications for its suitability for domestic use.  相似文献   
942.

Background, aim, and scope  

Carbonyl compounds have been paid more and more attention because some carbonyl species have been proven to be carcinogenic or a risk for human health. Plant leaves are both an important emission source and an important sink of carbonyl compounds. But the research on carbonyl compounds from plant leaves is very scarce. In order to make an approach to the emission mechanism of plant leaves, a new method was established to extract carbonyl compounds from fresh plant leaves.  相似文献   
943.

Background, aim and scope  

European legislation stipulates that genetically modified organisms (GMO) have to be monitored to identify potential adverse environmental effects. A wealth of different types of monitoring data from various sources including existing environmental monitoring programmes is expected to accumulate. This requires an information system to efficiently structure, process and evaluate the monitoring data.  相似文献   
944.

Background, aim and scope  

Weathering patinas in rocks are the result of interaction processes between rock surfaces and atmosphere, biosphere and soil. Therefore, their textural and mineral composition is strongly related to environmental and bioactivity conditions. Whereas the development of weathering patinas in atmospheric conditions is well documented (e.g. typical Mediterranean patina), only very few studies focus on their formation in a burial environment. Our study of patinas developed on the tumular structure of Reguers de Seró deals with the knowledge of burial patinas from a textural and mineralogical point of view. The aims of this study include: (1) the characterisation of the rock used in this megalithic monument as well as inferences regarding the origin of the raw material; (2) the evaluation of the patinas developed on the surface of the carved steles; and (3) the discussion of the environmental conditions (atmospheric or burial) that favoured the development of the patinas.  相似文献   
945.

Purpose  

Besides classical organic pollutants and pesticides, pharmaceuticals and their residues have nowadays become recognized as relevant environmental contaminants. The risks of these chemicals for aquatic ecosystems are well known, but information about the pharmaca-plant interactions and metabolic pathways is scarce. Therefore, we investigate the process of uptake of acetaminophen (N-Acetyl-4-aminophenol) by Brassica juncea, drug-induced defense responses and detoxification mechanisms in different plant parts.  相似文献   
946.

Introduction  

Within the last decade, numerous studies have investigated the role of environmental history on tolerance to stress of many organisms. This study aims to assess if Manila clams Ruditapes philippinarum may react differently to cadmium exposure and trematode parasite infection (Himasthla elongata) depending on their origin and environmental history in Arcachon Bay (France).  相似文献   
947.

Background, aim, and scope  

Pharmaceuticals are emerging pollutants widely used in everyday urban activities which can be detected in surface, ground, and drinking waters. Their presence is derived from consumption of medicines, disposal of expired medications, release of treated and untreated urban effluents, and from the pharmaceutical industry. Their growing use has become an alarming environmental problem which potentially will become dangerous in the future. However, there is still a lack of knowledge about long-term effects in non-target organisms as well as for human health. Toxicity testing has indicated a relatively low acute toxicity to fish species, but no information is available on possible sublethal effects. This study provides data on the physiological pathways involved in the exposure of Atlantic salmon as representative test species to three pharmaceutical compounds found in ground, surface, and drinking waters based on the evaluation of the xenobiotic-induced impairment resulting in the activation and silencing of specific genes.  相似文献   
948.

Background, aim, and scope  

Over the years, organic pollution in the environment has aroused people’s concern worldwide, especially persistent organic pollutants (POPs). Particularly in developing countries, plenty of concentrated organic wastewaters treated noneffectively are discharged into aquatic environments from chemical, textile, paper-making, and other industries to seriously threaten the surface and drinking water. The conventional wastewater treatment techniques are often helpless due to high cost with multilevel processing. Adsorption as an efficient method is often applied to the treatment of wastewater. The aim of this work is to develop an eco-friendly and cost-effective wastewater-sorbing material with weak acidic pink red B (APRB) and calcium carbonate (CaCO3) by reusing highly concentrated dye wastewater.  相似文献   
949.
A state-of-the-science thermodynamic model describing gas-particle absorption processes was used to predict the gas-particle partitioning of mixtures of approximately 60 carbonyl compounds emitted from low-emission gasoline-powered vehicles, three-way catalyst gasoline-powered vehicles, heavy-duty diesel vehicles under the idle-creep condition (HDDV idle), and heavy-duty diesel vehicles under the five-mode test (HDDV 5-mode). Exhaust was diluted by a factor of 120-580 with a residence time of approximately 43 sec. The predicted equilibrium absorption partitioning coefficients differed from the measured partitioning coefficients by several orders of magnitude. Time scales to reach equilibrium in the dilution sampling system were close to the actual residence time during the HDDV 5-mode test and much longer than the actual residence time during the other vehicle tests. It appears that insufficient residence time in the sampling system cannot uniformly explain the failure of the absorption mechanism to explain the measured partitioning. Other gas-particle partitioning mechanisms (e.g., heterogeneous reactions, capillary adsorption) beyond the simple absorption theory are needed to explain the discrepancy between calculated carbonyl partitioning coefficients and observed partitioning. Both of these alternative partitioning mechanisms imply great challenges for the measurement and modeling of semi-volatile primary organic aerosol (POA) species from motor vehicles. Furthermore, as emitted particle concentrations from newer vehicles approach atmospheric background levels, dilution sampling systems must fundamentally change their approach so that they use realistic particle concentrations in the dilution air to approximately represent real-world conditions. Samples collected with particle-free dilution air yielding total particulate matter concentrations below typical ambient concentrations will not provide a realistic picture of partitioning for semi-volatile compounds.  相似文献   
950.
The effect of sampling protocol on ambient air hydrocarbon mixing ratios was examined on eight sampling days in Los Angeles during 2007 and 2008. Four protocols, which were based on previously published multi-city urban hydrocarbon studies in the United States, were compared and differences were quantified. Whole air canister samples were collected and analyzed for nonmethane hydrocarbons (NMHCs). Differing sampling protocols resulted in large differences in mixing ratios, up to an order of magnitude, for certain NMHCs on the same sampling day. However, the magnitude of the variability between NMHC levels obtained by the four protocols was not consistent throughout the eight sampling days. It was found that sampling time, followed by sampling location, had the greatest influence on the magnitude of the mixing ratio. Ratios between hydrocarbons, often used in urban studies to gain information on emission sources, also varied depending on the protocol used. Comparison of absolute NMHC mixing ratios collected in urban environments using differing sampling protocols should be made with care.  相似文献   
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