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A project-based system for including farmers in the EU ETS 总被引:1,自引:0,他引:1
Farmers in the EU do not trade greenhouse gases under the Kyoto agreement. This is an empirical puzzle because agriculture is a significant contributor of greenhouse gases (GHG) in the EU and may harvest private net gains from trade. Furthermore, the US has strongly advocated land-use practices as 'the missing link' in past climate negotiations. We argue that farmers have relatively low marginal reduction costs and that consequences in terms of the effect on permit price and technology are overall positive in the EU Emission Trading System (ETS). Thus, we propose a project-based system for including the farming practices in the EU ETS that reduces the uncertainty from measuring emission reduction in this sector. The system encourages GHG reduction either by introducing a new and less polluting practice or by reducing the polluting activity. When doing so, farmers will receive GHG permits corresponding to the amount of reduction which can be stored for later use or sold in the EU ETS. 相似文献
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E. Tipping S. Lofts B. Frey C. Svendsen 《Environmental pollution (Barking, Essex : 1987)》2010,158(7):2465-2471
Published chronic toxicity data for Hg(II) added to soils were assembled and evaluated to produce a data set comprising 52 chronic end-points, five each for plants and invertebrates and 42 for microbes. With end-points expressed in terms of added soil Hg(II) contents, Critical Limits were derived from the 5th percentiles of species sensitivity distributions, values of 0.13 μg (g soil)−1 and 3.3 μg (g soil organic matter)−1 being obtained. The latter value exceeds the currently recommended Critical Limit, used to determine Hg(II) Critical Loads in Europe, of 0.5 μg (g soil organic matter)−1. We also applied the WHAM/Model VI chemical speciation model to estimate concentrations of Hg2+ in soil solution, and derived an approximate Critical Limit Function (CLF) that includes pH; log [Hg2+]crit = −2.15 pH −17.10. Because they take soil properties into account, the soil organic matter-based limit and the CLF provide the best assessment of toxic threat for different soils. For differing representative soils, each predicts a range of up to 100-fold in the dry weight-based content of mercury that corresponds to the Critical Limit. 相似文献
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Hanne Marie Kvamsdal Jens Hetland Geir Haugen Hallvard F. Svendsen Fredrik Major Vemund Kårstad Göran Tjellander 《International Journal of Greenhouse Gas Control》2010,4(4):613-622
A post-combustion CO2 capture process intended for offshore operations has been designed and optimised for integration with a natural gas-fired power plant on board a floating structure developed by the Norway-based company Sevan Marine ASA—designated Sevan GTW (gas-to-wire). The concept is constrained by the structure of the floater carrying a SIEMENS modular power system rated at 450 MWe, with a capture rate of 90% and CO2 compression (1.47 Mtpa) for pipeline pressure at 12 MPa. A net efficiency of 45% (based on a lower heating value) is estimated for the system with CO2 capture, thus suggesting that the post-combustion CO2 capture system is accountable for a fuel penalty of nine percentage points.The rationale behind the technology selection is the urgency of replacing the dispersed aero-derivative gas turbines which power the offshore oil and gas production units in Norwegian waters with near-zero emission power.As (inherently) fresh water usually constitutes a limiting factor in sea operations, efforts are made to obtain a neutral water balance to obtain an optimal design. This is primarily achieved by controlling the cleaned flue gas temperature at the top of the absorber column. 相似文献
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It is important to understand the aetiology of interactive mixtures effects (i.e. synergism and antagonism) if results from known cases are to be extrapolated to untested combinations. The key role of toxicokinetics in determining internal concentrations at target sites means that understanding chemical uptake in mixtures is an essential requirement for mechanistic understanding of interactions. In this paper, a combined approach using mixture toxicity testing, toxicokinetic studies and modelling has been used to address the link between joint toxicity and internal concentration. The study is conducted in Lumbricid earthworms with a binary mixture of a metal (nickel) and an organophosphate insecticide (chlorpyrifos) not a priori expected to show interactive toxicity. As expected from their dissimilar modes of action and detoxification, exposure to combinations of nickel and chlorpyrifos resulted in additive toxicity. Measurement of internal concentrations indicated that both chemicals were rapidly accumulated (within 3 days) to equilibrium. When exposed as a mixture, Ni uptake followed the same pattern as found for the single chemical. This was not the case for chlorpyrifos which showed a faster rate of uptake and elimination and a slightly higher equilibrium concentration in a mixture. That the difference in chlorpyrifos kinetics in the mixture did not result in interactive toxicity highlights the need to assess chemical toxicodynamics as well as toxicokinetics. Measurement of chlorpyrifos-oxon identified the presence of this toxic form but implementation of more complex approaches encompassing toxicogenomics and epigenetics are ultimately needed to resolve the toxicokinetic to toxicodynamic link for these chemicals. 相似文献
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Spurgeon DJ Lawlor A Hooper HL Wadsworth R Svendsen C Thomas LD Ellis JK Bundy JG Keun HC Jarup L 《Environmental pollution (Barking, Essex : 1987)》2011,159(12):3425-3432
The relationship of measured or modelled Cd concentrations in soil, house dust and available to plants with human urinary Cd concentrations were assessed in a population living around a Cd/Pb/Zn smelter in the UK. Modelled air concentrations explained 35% of soil Cd variation indicating the smelter contributed to soil Cd loads. Multi-variate analysis confirmed a significant role of biological and life-style factors in determining urinary Cd levels. Significant correlations of urinary Cd with soil, house dust and modelled plant available Cd concentrations were not, however, found. Potential reasons for the absence of clear relationships include limited environmental contact in urban populations; the role of undefined factors in determining exposure; and the limited spatial scope of the survey which did not sample from the full pollution gradient. Further, the absence of any significant relationship indicates that environmental measures provide limited advantage over atmospheric model outputs for first stage human exposure assessment. 相似文献
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Hanna Knuutila Hallvard F. Svendsen Mikko Anttila 《International Journal of Greenhouse Gas Control》2009,3(2):143-151
In this work the feasibility of a CO2 capture system based on sodium carbonate–bicarbonate slurry and its integration with a power plant is studied. The results are compared to monoethanolamine (MEA)-based capture systems. Condensing power plant and combined heat and power plant with CO2 capture is modelled to study the feasibility of combined heat and power plant for CO2 capture.Environmental friendly sodium carbonate would be an interesting chemical for CO2 capture. Sodium carbonate absorbs CO2 forming sodium bicarbonate. The low solubility of sodium bicarbonate is a weak point for the sodium carbonate based liquid systems since it limits the total concentration of carbonate. In this study the formation of solid bicarbonate is allowed, thus forming slurry, which can increase the capacity of the solvent. With this the energy requirement of stripping of the solvent could potentially be around 3.22 MJ/kg of captured CO2 which is significantly lower than with MEA based systems which typically have energy consumption around 3.8 MJ/kg of captured CO2.Combined heat and power plants seem to be attractive for CO2 capture because of the high total energy efficiency of the plants. In a condensing power plant the CO2 capture decreases directly the electricity production whereas in a combined heat and power plant the loss can be divided between district heat and electricity according to demand. 相似文献
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依法发展再生资源产业——对《再生资源回收管理办法》的解读与思考 总被引:1,自引:0,他引:1
依法发展再生资源产业是推行循环经济的必然要求。解读《再生资源回收管理办法,》认为实现再生资源产业的全面发展,还需建立健全再生资源法律体系。 相似文献