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11.
Water-soluble inorganic ions in aerosol samples have been studied. The sample collection took place during summer in 2003 at a European background site which is operating within the framework of the European Monitoring and Evaluation Program. Gent type PM10 stacked filter unit (SFU) samplers were operated in parallel on a day and night basis to collect particles in separate coarse (2.0-10 microm) and fine (<2.0 microm) size fractions. Particulate masses were measured gravimetrically; the filters from one of the SFU samplers were analyzed by particle-induced X-ray emission spectrometry (PIXE) and instrumental neutron activation analysis (INAA). Filters from the other SFU sampler were analyzed by ion chromatography (IC) for major inorganic anions (MSA-, NO2(-), NO3(-), Cl-, Br-, SO4(2-), oxalate) and cations (Na+, K+, NH4(+), Mg2+, Ca2+). The water-soluble inorganic ions measured were responsible for 44% and 16% of the total fine and coarse particulate mass, respectively. In the fine size fraction, the main ionic components were SO4(2-) and NH4(+) accounting for about 90% of fine ionic mass. In the coarse fraction the main ionic components were Ca2+ and NO3(-), followed by SO4(2-). Significant day and night difference in the mass concentrations was observed only for fine NO3(-). The molar ratios of fine NH4(+) to SO4(2-) indicated their complete neutralization to (NH4)2SO4. According to the cation-to-anion ratios the coarse particles were alkaline, while the fine particles were slightly acidic or neutral. By comparing the corresponding concentrations obtained from PIXE/INAA and IC, we determined the water-extractable part of the individual species. We also investigated the effect of long-range transported air masses on the local air concentrations, and we found that the air quality of this background monitoring station was affected by regional pollution sources.  相似文献   
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The 1999/31 Elemental Carbon Directive sets strict rules on the disposal of untreated municipal solid waste in the European Union countries and forces a reduction of the biodegradable quantities disposed off to landfills up to 35% of the amount produced in 1995 in the coming decade. More environmentally friendly waste management options shall be promoted under the framework of the Community Waste Strategy ([96] 399 Final). In this context, the production and thermal use of solid recovered fuels (SRFs), derived from nonhazardous bioresidues and mixed- and mono-waste streams, could be a key element in a future waste management system. Within the scope of the European Demonstration Project, RECOFUEL, SRF cocombustion was demonstrated in two large-scale lignite-fired coal boilers at RWE power station in Weisweiler, Germany. As a consequence of the high biogenic share of the cocombusted material, this approach can be considered beneficial following European Directive 2001/77/EC on electricity from renewable energy sources (directive). During the experimental campaign, the share of SRF in the overall thermal input was adjusted to approximately 2%, resulting into a feeding rate of approximately 25 t/hr. The measurement campaign included boiler measurements in different locations, fuel and ash sampling, and its characterization. The corrosion rates were monitored by dedicated corrosion probes. The overall results showed no significant influence of SRF cocombustion on boiler operation, emissions behavior, and residues quality for the thermal shares applied. Also, no effect of the increased chlorine concentration of the recovered fuel was observed in the flue gas path after the desulfurization unit.  相似文献   
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The efficiency of the polymerase chain reaction (PCR) in detecting the cystic fibrosis (CF) ΔF508 mutation (which is the most common mutation of CF) was assessed in single human blastomeres. Twenty-one human immature oocytes (germinal-vesicle-stage oocytes) that had been donated for research were matured in vitro and a single spermatozoon from a carrier of the CF ΔF508 mutation was injected into the ooplasm. Fourteen embryos were obtained after intracytoplasmic sperm injection (ICSI). PCR analysis was carried out on 70 single blastomeres isolated from these 14 embryos. The results showed that the efficiency of DNA amplification by PCR in single nucleate blastomeres was 94 per cent (59/63). There were no false-positive results since none of the blank samples or the blastomeres without a nucleus showed an amplified signal. We found that nine embryos were homozygous for the unaffected genotype and that four embryos were heterozygous since they contained both the unaffected and the ΔF508 genotype. In a four-cell embryo, we observed the homozygous unaffected genotype in one blastomere and a heterozygous ΔF508/unaffected genotype in the other three blastomeres.  相似文献   
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Rehabilitation of degraded forest land through implementation of carbon-sink projects can increase terrestrial carbon (C) stock. However, carbon emissions outside the project boundary, which is commonly referred to as leakage, may reduce or negate the sequestration benefits. This study assessed leakage from carbon-sink projects that could potentially be implemented in the study area comprised of 11 sub-districts in the Batanghari District, Jambi Province, Sumatra, Indonesia. The study estimates the probability of a given land use/cover being converted into other uses/cover, by applying a logit model. The predictor variables were: proximity to the center of the land use area, distance to transportation channel (road or river), area of agricultural land, unemployment (number of job seekers), job opportunities, population density and income. Leakage was estimated by analyzing with and without carbon-sink projects scenarios. Most of the predictors were estimated as being significant in their contribution to land use cover change. The results of the analysis show that leakage in the study area can be large enough to more than offset the project’s carbon sequestration benefits during the period 2002–2012. However, leakage results are very sensitive to changes of carbon density of the land uses in the study area. By reducing C-density of lowland and hill forest by about 10% for the baseline scenario, the leakage becomes positive. Further data collection and refinement is therefore required. Nevertheless, this study has demonstrated that regional analysis is a useful approach to assess leakage.  相似文献   
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Dioxin-like activity was measured in the serum of 1425 Flemish men and women via the CALUX assay. The adults, aged between 50 and 65 years, participated in a large biomonitoring program, executed by the Flemish Center of Expertise for Environment and Health between 2002 and 2006. Within the context of this biomonitoring program also dietary intake of dioxin-like contaminants was assessed through a food frequency questionnaire. The relation between the estimated dietary intake and the dioxin-like activity in serum was evaluated using multivariate analyses: a logistic model was performed on the total population, while a linear regression analysis was done on the subsample with quantifiable dioxin activity levels in serum. Region, gender, age, BMI, smoking status, as well as dietary habits were entered in the model, with dioxin level as an outcome estimate. Both the logistic and linear model confirmed the contribution of dietary intake to the dioxin activity measured in serum. Also BMI and region were found to be associated with dioxin activity levels.  相似文献   
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To assess whether nitrogen (N) content and δ15N ratios in nitrophytic lichen species (Xanthoria parietina (L.) Th. Fr. (1860) and Physcia spp. (Schreb.) Michaux (1803)) reflect the quantity and quality of atmospheric N loads, 348 lichen samples from 174 sampling grid cells were investigated in the western part of Germany. The analysed lichen N content ranged between 0.98 and 4.28 % and δ15N ratios between ?15.2 and ?1.3?‰. Based on the N concentrations and the δ15N ratios of lichens, different landscape categories and coupled N deposition rates could be inferred for different regions of Germany. By analysing environmental variables like altitude, ammonia emission density, livestock unit and different defined deposition types, a direct relationship was found between lichen chemistry and N compounds produced from agricultural activity. The results support the development of a monitoring method which could be used nationally or even internationally to support current N deposition measurements, by providing reliable information on the quantity and quality of N deposition in high N environments.  相似文献   
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