996 resultados para carbon permit trading


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A novel approach to measure carbon dioxide (CO2) in gaseous samples, based on a precise and accurate quantification by (13)CO2 internal standard generated in situ is presented. The main goal of this study was to provide an innovative headspace-gas chromatography-mass spectrometry (HS-GC-MS) method applicable in the routine determination of CO2. The main drawback of the GC methods discussed in the literature for CO2 measurement is the lack of a specific internal standard necessary to perform quantification. CO2 measurement is still quantified by external calibration without taking into account analytical problems which can often occur considering gaseous samples. To avoid the manipulation of a stable isotope-labeled gas, we have chosen to generate in situ an internal labeled standard gas ((13)CO2) on the basis of the stoichiometric formation of CO2 by the reaction of hydrochloric acid (HCl) with sodium hydrogen carbonate (NaH(13)CO3). This method allows a precise measurement of CO2 concentration and was validated on various human postmortem gas samples in order to study its efficiency.

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The hydrogen and oxygen isotopes of water and the carbon isotope composition of dissolved inorganic carbon (DIC) from different aquifers at an industrial site, highly contaminated by organic pollutants representing residues of the former gas production, have been used as natural tracers to characterize the hydrologic system. On the basis of their stable isotope compositions as well as the seasonal variations, different groups of waters (precipitation, surface waters, groundwaters and mineral waters) as well as seasonably variable processes of mixing between these waters can clearly be distinguished. In addition, reservoir effects and infiltration rates can be estimated. In the northern part of the site an influence of uprising mineral waters within the Quaternary aquifers, presumably along a fault zone, can be recognized. Marginal infiltration from the Neckar River in the cast and surface water infiltration adjacent to a steep hill on the western edge of the site with an infiltration rate of about one month can also be resolved through the seasonal variation. Quaternary aquifers closer to the centre of the site show no seasonal variations, except for one borehole close to a former mill channel and another borehole adjacent to a rain water channel. Distinct carbon isotope compositions and concentrations of DIC for these different groups of waters reflect variable influence of different components of the natural carbon cycle: dissolution of marine carbonates in the mineral waters, biogenic, soil-derived CO2 in ground- and surface waters, as well as additional influence of atmospheric CO2 for the surface waters. Many Quaternary aquifer waters have, however, distinctly lower delta(13)C(DIC) values and higher DIC concentrations compared to those expected for natural waters. Given the location of contaminated groundwaters at this site but also in the industrially well-developed valley outside of this site, the most likely source for the low C-13(DIC) values is a biodegradation of anthropogenic organic substances, in particular the tar oils at the site.

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The empirical finding of an inverse U-shaped relationship between per capita income and pollution, the so-called Environmental Kuznets Curve (EKC), suggests that as countries experience economic growth, environmental deterioration decelerates and thus becomes less of an issue. Focusing on the prime example of carbon emissions, the present article provides a critical review of the new econometric techniques that have questioned the baseline polynomial specification in the EKC literature. We discuss issues related to the functional form, heterogeneity, “spurious” regressions and spatial dependence to address whether and to what extent the EKC can be observed. Despite these new approaches, there is still no clear-cut evidence supporting the existence of the EKC for carbon emissions. JEL classifications: C20; Q32; Q50; O13 Keywords: Environmental Kuznets Curve; Carbon emissions; Functional form; Heterogeneity; “Spurious” regressions; Spatial dependence.Residential satisfaction is often used as a barometer to assess the performance of public policy and programmes designed to raise individuals' well-being. However, the fact that responses elicited from residents might be biased by subjective, non-observable factors casts doubt on whether these responses can be taken as trustable indicators of the individuals' housing situation. Emotional factors such as aspirations or expectations might affect individuals' cognitions of their true residential situation. To disentangle this puzzle, we investigated whether identical residential attributes can be perceived differently depending on tenure status. Our results indicate that tenure status is crucial not only in determining the level of housing satisfaction, but also regarding how dwellers perceive their housing characteristics. Keywords: Housing satisfaction, subjective well-being, homeownership. JEL classification: D1, R2.

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In a market in which sellers compete by posting mechanisms, we study how the properties of the meeting technology affect the mechanism that sellers select. In general, sellers have incentive to use mechanisms that are socially efficient. In our environment, sellers achieve this by posting an auction with a reserve price equal to their own valuation, along with a transfer that is paid by (or to) all buyers with whom the seller meets. However, we define a novel condition on meeting technologies, which we call “invariance,” and show that the transfer is equal to zero if and only if the meeting technology satisfies this condition.

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Domestic action on climate change is increasingly important in the light of the difficulties with international agreements and requires a combination of solutions, in terms of institutions and policy instruments. One way of achieving government carbon policy goals may be the creation of an independent body to advise, set or monitor policy. This paper critically assesses the Committee on Climate Change (CCC), which was created in 2008 as an independent body to help move the UK towards a low carbon economy. We look at the motivation for its creation in terms of: information provision, advice, monitoring, or policy delegation. In particular we consider its ability to overcome a time inconsistency problem by comparing and contrasting it with another independent body, the Monetary Policy Committee of the Bank of England. In practice the Committee on Climate Change appears to be the ‘inverse’ of the Monetary Policy Committee, in that it advises on what the policy goal should be rather than being responsible for achieving it. The CCC incorporates both advisory and monitoring functions to inform government and achieve a credible carbon policy over a long time frame. This is a similar framework to that adopted by Stern (2006), but the CCC operates on a continuing basis. We therefore believe the CCC is best viewed as a "Rolling Stern plus" body. There are also concerns as to how binding the budgets actually are and how the budgets interact with other energy policy goals and instruments, such as Renewable Obligation Contracts and the EU Emissions Trading Scheme. The CCC could potentially be reformed to include: an explicit information provision role; consumption-based accounting of emissions and control of a policy instrument such as a balanced-budget carbon tax.

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A continuum of carbon, from atmospheric CO2 to secondary calcium carbonate, has been studied in a soil associ- ated with scree slope deposits in the Jura Mountains of Switzerland. This approach is based on former studies conducted in other environments. This C continuum includes atmospheric CO2, soil organic matter (SOM), soil CO2, dissolved inorganic carbon (DIC) in soil solutions, and secondary pedogenic carbonate. Soil parameters (pCO2, temperature, pH, Cmin and Corg contents), soil solution chemistry, and isotopic compositions of soil CO2, DIC, carbonate and soil organic matter (δ13CCO2, δ13CDIC, δ13Ccar and δ13CSOM values) have been monitored at different depths (from 20 to 140 cm) over one year. Results demonstrated that the carbon source in secondary carbonate (mainly needle fiber calcite) is related to the dissolved inorganic carbon, which is strongly dependent on soil respiration. The heterotrophic respiration, rather than the limestone parent material, seems to control the pedogenic carbon cycle. The correlation of δ13Corg values with Rock-Eval HI and OI indices demonstrates that, in a soil associated to scree slope deposits, the main process responsible for 13C-enrichment in SOM is related to bac- terial oxidative decarboxylation. Finally, precipitation of secondary calcium carbonate is enhanced by changes in soil pCO2 associated to the convective movement of air masses induced by temperature gradients (heat pump effect) in the highly porous scree slope deposits. The exportation of soil C-leachates from systems such as the one studied in this paper could partially explain the "gap in the European carbon budget" reported by recent studies.

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The study was performed at OCAS, the Steel Research Centre of ArcelorMittal for the Industry market. The major aim of this research was to obtain an optimized tensile testing methodology with in-situ H-charging to reveal the hydrogen embrittlement in various high strength steels. The second aim of this study has been the mechanical characterization of the hydrogen effect on hight strength carbon steels with varying microstructure, i.e. ferrite-martensite and ferrite-bainite grades. The optimal parameters for H-charging - which influence the tensile test results (sample geometry type of electrolyte, charging methods effect of steel type, etc.) - were defined and applied to Slow Strain Rate testing, Incremental Step Loading and Constant Load Testing. To better understand the initiation and propagation of cracks during tensile testing with in-situ H-charging, and to make the correlation with crystallographic orientation, some materials have been analyzed in the SEM in combination with the EBSD technique. The introduction of a notch on the tensile samples permits to reach a significantly improved reproducibility of the results. Comparing the various steel grades reveals that Dual Phase (ferrite-martensite) steels are more sensitive to hydrogen induced cracking than the FB (ferritic-bainitic) ones. This higher sensitivity to hydrogen was found back in the reduced failure times, increased creep rates and enhanced crack initiation (SEM) for the Dual Phase steels in comparison with the FB steels.

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In this study the hepatic lipoprotein lipase (LPL), activity was evaluated in adult female mice acclimatized at 5-C and submitted to carbon tetrachloride (CCI) or ethionine, in order to determine the possible role of this enzuyme in the fatty liver. The results were compared with those obtained in mice kept at room temperature (27-C) that the same hepatoesteatosis inducing agent. In contrast to animals kept at room temperature, in cold aclimatized mice neither the enhancement of the LPL-liver activity by the action of CCI or ethionine occurred nor the development of fatty infiltration in the liver was observed. We conclude that the low temperature induced a protective effect against CCI or ethionine-induced fatty liver that was correlated with the no-increase of the hepatic LPL activity.

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The enhanced flow in carbon nanotubes is explained using a mathematical model that includes a depletion layer with reduced viscosity near the wall. In the limit of large tubes the model predicts no noticeable enhancement. For smaller tubes the model predicts enhancement that increases as the radius decreases. An analogy between the reduced viscosity and slip-length models shows that the term slip-length is misleading and that on surfaces which are smooth at the nanoscale it may be thought of as a length-scale associated with the size of the depletion region and viscosity ratio. The model therefore provides a physical interpretation of the classical Navier slip condition and explains why `slip-lengths' may be greater than the tube radius.

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Hydrocarbon distributions and stable isotope ratios of carbonates (delta(13)C(car), delta(18)O(car)), kerogen (delta(13)C(ker)), extractable organic matter (delta(13)C(EOM)) and individual hydrocarbons of Liassic black shale samples from a prograde metamorphic sequence in the Swiss Alps were used to identify the major organic reactions with increasing metamorphic grade. The studied samples range from the diagenetic zone (< 100 degrees C) to amphibolite facies (similar to 550 degrees C). The samples within the diagenetic zones (< 100 and 150 degrees C) are characterized by the dominance of C-< 20 n-alkanes, suggesting an origin related with marine and/or bacterial inputs. The metamorphic samples (200 to 550 degrees C) have distributions significantly dominated by C-12 and C-13 n-alkanes, C-14, C-16 and C-18 n-alkylcyclopentanes and to a lesser extend C-15, C-17 and C-21 n-alkylcyclohexanes. The progressive C-13-enrichment (up to 3.9 parts per thousand) with metamorphism of the C-> 17 n-alkanes suggests the occurrence of cracking reactions of high molecular weight compounds. The isotopically heavier (up to 5.6 parts per thousand) C-< 17 n-alkanes in metamorphic samples are likely originated by thermal degradation of long-chain homologous with preferential release of isotopically light C-1 and C-2 radicals. The dominance of specific even C-number n-alkylcyclopentanes suggests an origin related to direct cyclization mechanism (without decarboxylation step) of algal or bacterial fatty acids occurring in reducing aqueous metamorphic fluid conditions. The regular increase of the concentrations of n-alkylcycloalkanes vs. C-> 13 n-alkanes with metamorphism suggests progressive thermal release of kerogen-linked fatty acid precursors and degradation of n-alkanes. Changes of the steroid and terpenoid distributions are clearly related to increasing metamorphic temperatures. The absence of 18 alpha(H)-22,29,30-trisnorneohopane (Ts), the occurrence of 17 beta(H)-trisnorhopane, 17 beta(H), 21 alpha(H)-hopanes in the C-29 to C-31 range and 5 alpha(H),14 alpha(H),17 alpha(H)-20R C-27, C-29 steranes in the low diagenetic samples (< 100 degrees C) are characteristic of immature bitumens. The higher thermal stress within the upper diagenetic zone (150 degrees C) is marked by the presence of Ts, the disappearance of 17 beta(H)-trisnorhopane and thermodynamic equilibrium of the 22S/(22S + 22R) homohopane ratios. The increase of the alpha alpha alpha-sterane 20S/(20S + 20R) and 20R beta beta/(beta beta + alpha alpha) ratios (from 0.0 to 0.55 and from 0.0 to 0.40, respectively) in the upper diagenetic zone indicates the occurrence of isomerization reactions already at < 150 degrees C. However, the isomerization at C-20 (R -> S) reaches thermodynamic equilibrium values already at the upper diagenesis (similar to 150 degrees C) whereas the epimerisation at C-14 and C-17 (alpha alpha ->beta beta) arrives to constant values in the lower anchizone (similar to 200 degrees C). The ratios Ts vs. 17 alpha(H)-22,29,30-trisnorneohopane [(Ts/(Ts + Tm)] and 18 alpha(H)-30-norneohopane (C29Ts) vs. 17 alpha(H),21 beta(H)-30-norhopane [C29Ts/(C29Ts + C-29)] increase until the medium anchizone (200 to 250 degrees C) from 0.0 to 0.96 and from 0.0 to 0.44, respectively. An opposite trend owards lower values is observed in the higher metamorphic samples. The occurrence of specific hydrocarbons (e.g., n-alkylcyclopentanes, cadalene, hydrogenated aromatic compounds) in metamorphic samples points to kerogen degradation reactions most probably occurring in the presence of water and under reducing conditions. The changes of hydrocarbon distributions and carbon isotopic compositions of n-alkanes related to metamorphism suggest that the organic geochemistry may help to evaluate the lowest grades of prograde metamorphism. Copyright (c) 2005 Elsevier Ltd.

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IPH responded to the Department of Justice, Equality and Defence review of the voluntary Code of Practice for the display and sale of alcohol in supermarkets, convenience stores and similar mixed trading outlets. The voluntary Code was introduced in 2008 as an alternative to the statutory rules for structural separation of alcohol products in mixed trading outlets which are set out in section 9 of the Intoxicating Liquor Act 2008. Interested bodies and individuals were invited to submit comments on the Compliance Report for 2011 and on the effectiveness of the voluntary approach to structural separation by 20th December 2011. The Minister said he intended to also seek the views of the Minister for Health and the Joint Oireachtas Committee on Justice, Defence and Equality before reaching any decision on whether to bring the statutory rules in the 2008 Act into operation.

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The main aim of this work is to define an environmental tax on products and services based on their carbon footprint. We examine the relevance of conventional life cycle analysis (LCA) and environmentally extended input-output analysis (EIO) as methodological tools to identify emission intensities of products and services on which the tax is based. The short-term price effects of the tax and the policy implications of considering non-GHG are also analyzed. The results from the specific case study on pulp production show that the environmental tax rate based on the LCA approach (1,8%) is higher than both EIO approaches (0,8% for product and 1,4% for industry approach), but they are comparable. Even though LCA is more product specific and provides detailed analysis, EIO would be the more relevant approach to apply economy wide environmental tax. When the environmental tax considers non-GHG emissions instead of only CO2, sectors such as agriculture, mining of coal and extraction of peat, and food exhibit higher environmental tax and price effects. Therefore, it is worthwhile for policy makers to pay attention on the implication of considering only CO2 tax or GHG emissions tax in order for such a policy measure to be effective and meaningful. Keywords: Environmental tax; Life cycle analysis; Environmental input-output analysis.

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Response to the Office of Fair Trading on the Care Home Market