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151.
152.
Henrik Fred Larsen Morten Søes Hansen Michael Hauschild 《Journal of Cleaner Production》2009,17(2):115-128
Existing product life cycle assessment (LCA) studies on offset printed matter all point at paper as the overall dominating cause of environmental impacts. All studies focus on energy consumption and the dominating role of paper is primarily based on the energy-related impact categories: global warming, acidification and nutrient enrichment. Ecotoxicity and human toxicity, which are related to emissions of chemicals, etc., are only included to a limited degree or not at all. In this paper we include the impacts from chemicals emitted during the life cycle of sheet fed offset printed matter. This is done by making use of some of the newest knowledge about emissions from the production at the printing industry combined with knowledge about the composition of the printing materials used. In cases with available data also upstream emissions from the production of printing materials are included. The results show that inclusion of the chemical emission-related impacts makes the EDIP97 impact profile of sheet fed offset products much more varied, as well for the normalised profiles as for the profiles weighted by distance to political environmental targets. Especially the ecotoxicity impact potential related to the production stage may contribute significantly, and the use of paper no longer becomes the overall dominating factor driving the environmental impacts. 相似文献
153.
Emission of metals in the urbanenvironment is a growing concern throughout theworld. In order to identify metal emissionssources in the Stockholm metropolitan region, amethod for detailed mapping of roof coatings andother urban land covers has been developedconducted. High accuracy area calculation ofcopper roof coatings based on scanned aerialphotography was used. The geometric resolution ofthe digital photographs was 0.4 metre. Imagelayers with identified copper roof objects weremerged with a digital elevation model of 1 metregeometric resolution. The slope gradient for eachroof was calculated in order to account for slopein the calculation of roof areas. In total,622,590 m2 of copper roofs were accounted,of which 176,845 m2 and 447,745 m2represent new and patinated copper respectively.The number of copper roofs larger than 1,000m2 was 142. Applying corrosion and runoffrates on these figures, a yearly Cu flux ofapproximately 1,200 kg in Stockholm may bederived from copper coated building. 相似文献
154.
Phosphorous control in a eutrophied reservoir 总被引:1,自引:0,他引:1
H. Márquez-Pacheco A. M. Hansen A. Falcón-Rojas 《Environmental science and pollution research international》2013,20(12):8446-8456
Water in lakes and reservoirs accumulate phosphorous (P) from both internal and external loads. The external P load (EPL) coming from the watershed is considered to be the main cause of eutrophication of water bodies, and control strategies therefore focus on its reduction. However, algae blooms and anoxic conditions often continue even after EPL have been controlled, being the internal P load (IPL) originating from the sediment the main sources of P. To assess the efficiency of the adsorbent Phoslock (a modified bentonite) in controlling P concentrations in water and immobilize releasable P in sediments, mesocosm trials were carried out in a eutrophied reservoir and a model was described and applied that determines the amount of adsorbent and the application frequency necessary to control P concentrations in a eutrophied reservoir. The mesocosm trials confirm that Phoslock reduced P concentrations to or below the limits that define water in mesotrophic state, in approximately 2 weeks. The modeling results suggest that periodic reapplications of the adsorbent are required, unless EPL is reduced by 36 %, which allows the P concentrations in the water column to be constant. Such reduction in EPL would allow future applications of the adsorbent to be required only for control of IPL. The developed model allows planning remediation actions by determining quantities and frequencies for application of adsorbents for P control in eutrophied lakes and reservoirs. 相似文献
155.
Study of poverty alleviation strategy based on labor force quality improvement and ecological protection in Western China 总被引:1,自引:0,他引:1
Fragile ecological environment and poverty correlate to and reinforce each other closely in Western China.At the same time,Western China is also the most prominent area of the knowledge and human poverty with very low labor force quality.On the basis of analyzing the characteristics of poverty in Western China,this paper studies the coupling relationship between fragile ecological environment and poverty in Western China,including the impacts of fragile environment on poverty occurrence and the effects of ecological construction on poverty alleviation.It also analyzed how low labor quality causes persistent poverty in the western region.At the end of the paper,strategies of diversity poverty alleviation in Western China are suggested based on sustainable development,including education improvement,ecological construction,industries development,infrastructure construction,planning institution innovation,and so on. 相似文献
156.
OBJECTIVE: Polychlorinated biphenyls (PCBs) and related compounds elicit a diverse spectrum of toxic responses. Additionally, they are able to pass through the human placenta. The aim of the presented data was to compare the action of low-chlorinated (Delor 103) and (Delor 106) high-chlorinated biphenyls on placental steroidogenesis. METHODS: Explants of human placental tissue were used to test differences in PCBs accumulation and influence on placental steroidogenesis. Delor 103 or 106, were added daily for six days at a dose of 200 pg from day 0 to day 6 of culture. The media in the control and experimental groups were changed every day, and collected and frozen for steroid analysis by RIA. Determinations of PCBs of tissue and medium were analysed by GC/MS/MS. RESULTS: Delor 103 was found at a higher level in the tissue than Delor 106. The first day of exposure to Delor 103 had no effect on the conversion of dehydroepiandrosterone (DHEA) to estradiol (E2) while there was a 2-fold decrease in E2 secretion from days 3 to 6. Conversely, Delor 106 caused an immediate increase in E2 secretion, which was maintained at higher levels throughout the exposure period. CONCLUSION: Differences between the accumulation of lower chlorinated and higher chlorinated biphenyls in human placental tissue and in the properties of the congeners can have multiple effects that may intensify or counteract the effects on uterine contraction by PCBs. 相似文献
157.
Park K Chow JC Watson JG Trimble DL Doraiswamy P Park K Arnott WP Stroud KR Bowers K Bode R Petzold A Hansen AD 《Journal of the Air & Waste Management Association (1995)》2006,56(4):474-491
Results from six continuous and semicontinuous black carbon (BC) and elemental carbon (EC) measurement methods are compared for ambient samples collected from December 2003 through November 2004 at the Fresno Supersite in California. Instruments included a multi-angle absorption photometer (MAAP; lambda = 670 nm); a dual-wavelength (lambda = 370 and 880 nm) aethalometer; seven-color (lambda = 370, 470, 520, 590, 660, 880, and 950 nm) aethalometers; the Sunset Laboratory carbon aerosol analysis field instrument; a photoacoustic light absorption analyzer (lambda = 1047 nm); and the R&P 5400 ambient carbon particulate monitor. All of these acquired BC or EC measurements over periods of 1 min to 1 hr. Twenty-four-hour integrated filter samples were also acquired and analyzed by the Interagency Monitoring of Protected Visual Environments (IMPROVE) thermal/optical reflectance carbon analysis protocol. Site-specific mass absorption efficiencies estimated by comparing light absorption with IMPROVE EC concentrations were 5.5 m2/g for the MAAP, 10 m2/g for the aethalometer at a wavelength of 880 nm, and 2.3 m2/g for the photoacoustic analyzer; these differed from the default efficiencies of 6.5, 16.6, and 5 m2/g, respectively. Scaling absorption by inverse wavelength did not provide equivalent light absorption coefficients among the instruments for the Fresno aerosol measurements. Ratios of light absorption at 370 nm to those at 880 nm from the aethalometer were nearly twice as high in winter as in summer. This is consistent with wintertime contributions from vehicle exhaust and from residential wood combustion, which is believed to absorb more shorter-wavelength light. To reconcile BC and EC measurements obtained by different methods, a better understanding is needed of the wavelength dependence of light-absorption and mass-absorption efficiencies and how they vary with different aerosol composition. 相似文献
158.
Edgerton ES Hartsell BE Saylor RD Jansen JJ Hansen DA Hidy GM 《Journal of the Air & Waste Management Association (1995)》2006,56(9):1325-1341
Deployment of continuous analyzers in the Southeastern Aerosol Research and Characterization Study (SEARCH) network began in 1998 and continues today as new technologies are developed. Measurement of fine particulate matter (PM2.5) mass is performed using a dried, 30 degrees C tapered element oscillating microbalance (TEOM). TEOM measurements are complemented by observations of light scattering by nephelometry. Measurements of major constituents include: (1) SO4(2-) via reduction to SO2; (2) NH4+ and NO3- via respective catalytic oxidation and reduction to NO, (3) black carbon (BC) by optical absorption, (4) total carbon by combustion to CO2, and (5) organic carbon by difference between the latter two measurements. Several illustrative examples of continuous data from the SEARCH network are presented. A distinctive composite annual average diurnal pattern is observed for PM2.5 mass, nitrate, and BC, likely indicating the influence of traffic-related emissions, growth, and break up of the boundary layer and formation of ammonium nitrate. Examination of PM2.5 components indicates the need to better understand the continuous composition of the unmeasured "other" category, because it contributes a significant fraction to total mass during periods of high PM2.5 loading. Selected episodes are presented to illustrate applications of SEARCH data. An SO2 conversion rate of 0.2%/hr is derived from an observation of a plume from a coal-fired power plant during early spring, and the importance of local, rural sources of NH3 to the formation of ammonium nitrate in particulate matter (PM) is demonstrated. 相似文献
159.
Rick D. Saylor Eric S. Edgerton Benjamin E. Hartsell Karsten Baumann D. Alan Hansen 《Atmospheric environment (Oxford, England : 1994)》2010,44(38):4994-5004
Continuous ammonia (NH3) measurements with a temporal resolution of 5 min were implemented at selected SEARCH sites in the southeastern U. S. during 2007. The SEARCH continuous NH3 instrument uses a citric acid denuder difference technique employing a dual-channel nitric oxide-ozone chemiluminescence analyzer. Data from two SEARCH sites are presented, Jefferson Street, Atlanta (JST) (urban), and Yorkville, Georgia (YRK) (rural), for the period July–December, 2007. Highest NHx (total ammonia = gaseous NH3 + PM2.5 NH4+) values were observed in August and September at both JST and YRK. Highest NH3 values occurred in August and September at JST, but in August through October at YRK. Lowest NH3 and NHx values occurred in December at both sites. YRK is significantly impacted by nearby poultry sources, routinely experiencing hourly average NH3 mixing ratios above 20 ppbv. Wind sector analysis clearly implicates the nearby poultry operations as the source of the high NH3 values. Weekday versus weekend differences in composite hourly mean diurnal profiles of NH3 at JST indicate that mobile sources have a measurable but relatively small impact on NH3 observed at that site, and little or no impact on NH3 observed at YRK. A distinctive composite mean hourly diurnal variation was observed at both JST and YRK, exhibiting maxima in the morning and evening with a broad minimum during midday. Analysis of observed NH3 diurnal variations from the literature suggests a hypothesized mechanism for the observed behavior based on interaction of local emissions and dry deposition with the formation and collapse of the dynamically mixed atmospheric boundary layer during the day and shallow nocturnal layer at night. Simple mixed layer concentration box model simulations confirm the plausibility of the suggested mechanism. 相似文献
160.
R. Garnier A. I. Bento C. Hansen J. G. Pilkington J. M. Pemberton A. L Graham 《Die Naturwissenschaften》2017,104(7-8):68
Nutrient availability is predicted to interact with herbivore population densities. Competition for low quality food at high density may reduce summer food intake, and in turn winter survival. Conversely, low population density may favor physiological recovery through better access to better quality spring forage. Here, we take advantage of the long-term study of the Soay sheep population of St. Kilda (Scotland) to measure plasma protein markers and immunity in two consecutive summers with contrasting population densities. We show that, following a winter die-off resulting in a shift to low population density, albumin and total proteins increased, but only in adult sheep. The effect was not solely attributable to selective disappearance of malnourished sheep. Similarly, the concentration of antibodies was higher following the die-off, potentially indicating recovery of immune function. Overall, our results are consistent with the physiological recovery of surviving individuals after a harsh winter. 相似文献