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201.
Batt AL  Kim S  Aga DS 《Chemosphere》2007,68(3):428-435
The occurrence of ciprofloxacin, sulfamethoxazole, tetracycline, and trimethoprim antibiotics in four full-scale wastewater treatment plants (WWTPs) that differ in design and operating conditions was determined. The WWTPs chosen utilized a variety of secondary removal processes, such as a two stage activated sludge process with a nitrification tank, extended aeration, rotating biological contactors, and pure oxygen activated sludge. Several of the WWTPs also employed an advanced treatment process, such as chlorination and UV radiation disinfection. The detected concentrations (microg/l) ranged from 0.20 to 1.4 for ciprofloxacin, 0.21 to 2.8 for sulfamethoxazole, 0.061 to 1.1 for tetracycline, and 0.21 to 7.9 for trimethoprim. The overall percent difference in the concentrations of the antibiotics in the effluent and influent of these antibiotics differed between plants and ranged from 33% to 97%. Based on these four full-scale WWTPs evaluated, the apparent removal of organic micropollutants in wastewater is dependent on a combination of biological and physico-chemical treatment processes and operating conditions of the treatment system.  相似文献   
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203.
1990年代哥伦比亚采取了一批保护环境的举措.这些最初表现为涉及若干团体(尤其工业团体)的独立志愿运动,由全国工业协会(ANDI)、哥伦比亚塑料工业协会(Acoplastico)和哥伦比亚安全理事会(CCS)协调.这些团体支持国际环境管理发展,尤其<责任关怀计划>.自1994-1995年以来,在当局愈来愈积极--但仍有待完善--的参与支持下,签订了许多协调协议.尽管尚有不足之处,但哥伦比亚迄今为止所取得的进展依然不失为可持续发展道路上一个可以效仿的范例.  相似文献   
204.
Objective. Surgical nurses’ work is physically and mentally demanding, possibly leading to work–family conflict (WFC). The current study tests WFC to be a risk factor for neck and lower back pain (LBP). Job influence and social support are tested as resources that could buffer the detrimental impact of WFC. Methods. Forty-eight surgical nurses from two university hospitals in Germany and Switzerland were recruited. WFC was assessed with the Work–Family Conflict Scale. Job influence and social support were assessed with the Copenhagen Psychosocial Questionnaire, and back pain was assessed with the North American Spine Society Instrument. Results. Multiple linear regression analyses confirmed WFC as a significant predictor of cervical pain (β?=?0.45, p?β?=?0.33, p?=?0.012). Job influence and social support did not turn out to be significant predictors and were not found to buffer the impact of WFC in moderator analyses. Conclusion. WFC is likely to affect neck and back pain in surgery nurses. Work–life interventions may have the potential to reduce WFC in surgery nurses.  相似文献   
205.
A simple and rapid method has been studied for the determination of acidic herbicides (2,4-D, Dichlorprop, Dichlorprop-p, Fluazifop, Fluroxypyr, MCPA, Mecoprop and Mecoprop-p) on cereals (rye). The method involves an alkaline hydrolysis with sodium hydroxide in order to release covalently bound compounds, prior to QuEChERS extraction, followed by neutralization and analysis via liquid chromatography-double mass spectrometry LC/MS/MS. The performance of the method either with or without alkaline hydrolysis was studied in terms of recovery rates and limit of quantification (LOQ). In either case, recoveries were determined at four spiking levels (0.02 mg/kg, 0.05 mg/kg, 0.1 mg/kg and 0.5 mg/kg) with 5 replicates for each level. Mean recoveries ranged from 90 to 120 %, whereas relative standard deviations (RSD %) proved to be less than 20 %. Quantitative analysis was carried out by the internal standard (Nicarbazin) and the LC/MS/MS analysis was performed in electrospray ionisation (ESI) negative mode using a Zorbax XCB Eclipse column. The developed method was applied to the analysis of several cereals commercially available like as rye flour, oat meal, oat flakes and dehusked oat. Residue levels were found below the limit of quantification (LOQ) of the method. The method has been tested in EU Proficiency Tests for cereals with good results.  相似文献   
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207.
Companies need to follow environmental laws as they affect their manufacturing systems, waste handling, and the management of soil on their properties to ensure that their properties are either improved or altered as little as possible. Thus, the objective of this study was to evaluate the use of energy dispersive X‐ray fluorescence spectrometry (EDXRF) to determine the concentrations of elements present in the soil at a manufacturer of products based on fiberglass where wastes from production activities have been deposited on the property.  相似文献   
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209.
Groundwater dependent ecosystems. Part I: Hydroecological status and trends   总被引:3,自引:0,他引:3  
Groundwater dependent ecosystems (GDEs) include valuable ecosystems such as springs, wetlands, rivers, lakes and lagoons. The protection of these systems and services they provide is highlighted by international agreements, i.e. Ramsar convention on wetlands, and regional legislation, i.e. the European Water Framework Directive. Groundwater provides water, nutrients and a relatively stable temperature. However, the role of groundwater in surface ecosystems is not fully understood. The ecosystem can depend on groundwater directly or indirectly, and the reliance can be continuous, seasonal or occasional. This has implications for the vulnerability of ecosystems, as some may be easily affected by external pressure. Conceptual models and quantitative assessments of how groundwater interacts with the environment are needed. GDEs are also threatened by different land use activities and climate change. Hence, we need to understand how GDEs are affected by changes in groundwater quantity and quality, as severe groundwater changes have been observed in many regions. This study examines key aspects of GDEs (hydrogeology, geochemistry and biodiversity) in order to improve conceptual understanding of the role of groundwater in such ecosystems. The status and baseline of different types of GDEs are discussed, with particular emphasis on past evidence of environmental change and potential thresholds and threats in GDEs in various parts of Europe with different land use, climate and geology.  相似文献   
210.
Groundwater in sufficient amounts and of suitable quality is essential for potable water supplies, crop irrigation and healthy habitats for plant and animal biocenoses. The groundwater resource is currently under severe pressure from land use and pollution and there is evidence of dramatic changes in aquifer resources in Europe and elsewhere, despite numerous policy measures on sustainable use and protection of groundwater. Little is known about how such changes affect groundwater dependent ecosystems (GDEs), which include various aquatic and terrestrial ecosystems above ground and inside the aquifer. Future management must take this uncertainty into account. This paper focuses on multiple aspects of groundwater science, policy and sustainable management. Examples of current management methods and practices are presented for selected aquifers in Europe and an assessment is made of the effectiveness of existing policies such as the European Water Framework Directive and the Habitat Directive in practice and of how groundwaters and GDEs are managed in various conditions. The paper highlights a number of issues that should be considered in an integrated and holistic approach to future management of groundwater and its dependent ecosystems.  相似文献   
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