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91.
This paper aims to present the relevant results of a Life Cycle Assessment (LCA) study conducted on printed matter under a sheet-fed offset printing process by a company located in northwestern Mexico. Different scenarios were simulated in order to support decisions related to the improvement of environmental performance along the production processes. The study design was based on the European Platform on Life Cycle Assessment (EPLCA), which is in line with the ISO 14040 and 14044:2006 standards on LCA. The scope of the study was cradle-to-gate, with emphasis on the production of printed matter. The method chosen for the impact assessment was Impact 2002+ with a combined midpoint–damage approach. The results of the study showed that the major contributors to adverse effects were, primarily electricity consumption followed by paper consumption during the printing operation, as well as consumption of ink to a small degree. As for the plate-making operation along with the generation of secondary products, the result was negative. This is essentially due to involvement of recyclable materials, thus contributing to the prevention of raw material extraction. The smallest impact was observed from processes involving cleaning products and LP gas. The main issues of concern stemming from the results are electricity consumption and printing – both activities dominate almost all the midpoint categories. Generation of secondary products also had a relative environmental impact along the supply chain. Cleaning agents and LP gas did not have a significant impact on the final results of the process.  相似文献   
92.
Rising levels of CO2 in the atmosphere have led to increased CO2 concentrations in the oceans. This enhanced carbon availability to the marine primary producers has the potential to change their nutrient stoichiometry, and higher carbon-to-nutrient ratios are expected. As a result, the quality of the primary producers as food for herbivores may change. Here, we present experimental work showing the effect of feeding Rhodomonas salina grown under different pCO2 (200, 400 and 800 μatm) on the copepod Acartia tonsa. The rate of development of copepodites decreased with increasing CO2 availability to the algae. The surplus carbon in the algae was excreted by the copepods, with younger stages (copepodites) excreting most of their surplus carbon through respiration and adult copepods excreting surplus carbon mostly as DOC. We consider the possible consequences of different excretory pathways for the ecosystem. A continued increase in the CO2 availability for primary production, together with changes in the nutrient loading of coastal ecosystems, may cause changes in the trophic links between primary producers and herbivores.  相似文献   
93.
Bad weather and rough seas continue to be a major cause for ship losses and is thus a significant contributor to the risk to maritime transportation. This stresses the importance of taking severe sea state conditions adequately into account, with due treatment of the uncertainties involved, in ship design and operation in order to enhance safety. Hence, there is a need for appropriate stochastic models describing the variability of sea states. These should also incorporate realistic projections of future return levels of extreme sea states, taking into account long-term trends related to climate change and inherent uncertainties. The stochastic ocean wave model presented in this paper exploits the flexible framework of Bayesian hierarchical space-time models. It allows modelling of complex dependence structures in space and time and incorporation of physical features and prior knowledge, yet at the same time remains intuitive and easily interpreted. Furthermore, by taking a Bayesian approach, the uncertainties of the model parameters are also taken into account. A regression component with $\text{ CO }_2$ as an explanatory variable has been introduced in order to extract long-term trends in the data. The model has been fitted by monthly maximum significant wave height data for an area in the North Atlantic ocean. The different components of the model will be outlined in the paper, and the results will be discussed. Furthermore, a discussion of possible extensions to the model will be given.  相似文献   
94.
95.

Purpose  

The two artificial sweeteners cyclamate (CYC) and acesulfame (ACE) have been detected in wastewater and drinking water treatment plants. As in both facilities ozonation might be applied, it is important to find out if undesired oxidation products (OPs) are formed.  相似文献   
96.
Previously, high concentrations of cadmium have been found in the hepatopancreas of the edible or brown crab (Cancer pagurus) sampled from positions north of about 67° N, compared to regions further south along the Norwegian coast, with no clear understanding why. In order to study a similar organism in the same ecosystem, the present study analyzed 210 shore crabs (Carcinus maenas) from four different locations along the Norwegian coast, two in the North and two in the South. The physiological variables size, sex, molting stage, hepatosomatic index, carapace color, and gonad maturation were registered, in attempt to explain the high inter-individual variation in cadmium levels in hepatopancreas. In contrast to the brown crabs, the shore crabs showed no clear geographical differences in cadmium concentrations. This indicates physiological differences between the two crab species. No clear and consistent correlations were found between cadmium levels and physiological parameters, except for sex, where cadmium concentration in hepatopancreas was twice as high in males compared to females. The cadmium levels also varied with season, with approximately 40 and 60% lower cadmium concentration in April than August for male and female shore crabs, respectively. None of the analyzed cadmium concentrations in muscle meat from claws exceeded EUs food safety limit, and low cadmium levels in soup prepared from shore crabs clearly indicated that this dish is not problematic regarding food safety.  相似文献   
97.
98.
Strand LT  Haaland S  Kaste O  Stuanes AO 《Ambio》2008,37(1):18-28
To provide baseline data for climate manipulation experiments in 11 small (30-268 m2) headwater catchments at Storgama, Telemark County, Southern Norway, we assessed the natural variability in site characteristics and runoff quality. Annual average concentrations in runoff at the sites have coefficients of variation between 26-61%, with the smallest values for total organic carbon (TOC) and carbon to nitrogen (C/N) ratios and the largest for inorganic nitrogen (N). The catchments have between two and five times higher concentrations of inorganic N, TOC, and total phosphorus than the larger (0.6 km2) Storgama watershed nearby. Concentrations of TOC and TON in runoff tend to increase with soil C and N content and with the volume of soil in the catchment. For nitrate (NO3) and ammonium in runoff, the reverse is true. In wet years the proportion of bare rock is a major predictor for the annual average NO3 concentration in runoff.  相似文献   
99.
The occurrence of organic micropollutants in ground- and surface waters has become an important concern for the drinking water industry, mainly because of possible related health effects. Due to the polar nature of some of these pollutants, they are not completely removed by traditional water treatment barriers. This paper offers an overview of priority organic micropollutants and their occurrence in Flemish and Dutch water sources. Furthermore, rejection by nanofiltration is qualitatively predicted for the selected priority micropollutants. The qualitative prediction is based on the values of key solute and membrane parameters in nanofiltration. Predicted values are then compared with experimental values obtained from literature. Overall, the qualitative predictions are roughly in agreement with literature values. Prediction based on key parameters may thus prove to be a very quick and useful technique to assess the implementation of nanofiltration as a treatment step for organic micropollutants in drinking water plant design.  相似文献   
100.
Emerging contaminants in wastewater and sewage sludge spread on agricultural soil can be transferred to the human food web directly by uptake into food crops or indirectly following uptake into forage crops. This study determined uptake and translocation of the organophosphates tris(1-chloro-2-propyl) phosphate (TCPP) (log K ow 2.59), triethyl-chloro-phosphate (TCEP) (log K ow 1.44), tributyl phosphate (TBP) (log K ow 4.0), the insect repellent N,N-diethyl toluamide (DEET) (log K ow 2.18) and the plasticiser N-butyl benzenesulfonamide (NBBS) (log K ow 2.31) in barley, wheat, oilseed rape, meadow fescue and four cultivars of carrot. All species were grown in pots of agricultural soil, freshly amended contaminants in the range of 0.6–1.0 mg/kg dry weight, in the greenhouse. The bioconcentration factors for root (RCF), leaf (LCF) and seed (SCF) were calculated as plant concentration in root, leaf or seed over measured initial soil concentration, both in dry weight. The chlorinated flame retardants (TCEP and TCPP) displayed the highest bioconcentration factors for leaf and seed but did not show the same pattern for all crop species tested. For TCEP, which has been phased out due to toxicity but is still found in sewage sludge and wastewater, LCF was 3.9 in meadow fescue and 42.3 in carrot. For TCPP, which has replaced TCEP in many products and also occurs in higher residual levels in sewage sludge and wastewater, LCF was high for meadow fescue and carrot (25.9 and 17.5, respectively). For the four cultivars of carrot tested, the RCF range for TCPP and TCEP was 10–20 and 1.7–4.6, respectively. TCPP was detected in all three types of seeds tested (SCF, 0.015–0.110). Despite that DEET and NBBS have log K ow in same range as TCPP and TCEP, generally lower bioconcentration factors were measured. Based on the high translocation of TCPP and TCEP to leaves, especially TCPP, into meadow fescue (a forage crop for livestock animals), ongoing risk assessments should be conducted to investigate the potential effects of these compounds in the food web.  相似文献   
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