4,190 research outputs found

    The Allocation of European Union Allowances: Lessons, Unifying Themes and General Principles

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    This paper is the concluding chapter of Rights, Rents and Fairness: Allocation in the European Emissions Trading Scheme, edited by the co-authors and forthcoming from Cambridge University Press. The main objective of this paper is to distill the lessons and general principles to be learnt from the allocation of allowances in the European Union Emission Trading Scheme (EU ETS), i.e. in the world’s first experience with allocating carbon allowances to sub-national entities. We discuss the lessons that emerge from this experience and make some comments on what seem to be more general principles informing the allocation process and on what are the global implications of the EU ETS. As has become obvious during the first allocation phase, the diversity of experience among the Member States is considerable, so that it must be understood that these lessons and unifying themes are drawn from the experience of most of the Member States, not necessarily from all. Lessons and unifying observations are grouped in three categories: those concerning the conditions encountered, the processes employed, and the actual choices.Climate Change, Emission Trading, Allocation, Fairness, EU Policy

    Acoustic and optical phonon dynamics from femtosecond time-resolved optical spectroscopy of superconducting iron pnictide Ca(Fe_0.944Co_0.056)_2As_2

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    We report temperature evolution of coherently excited acoustic and optical phonon dynamics in superconducting iron pnictide single crystal Ca(Fe_0.944Co_0.056)_2As_2 across the spin density wave transition at T_SDW ~ 85 K and superconducting transition at T_SC ~20 K. Strain pulse propagation model applied to the generation of the acoustic phonons yields the temperature dependence of the optical constants, and longitudinal and transverse sound velocities in the temperature range of 3.1 K to 300 K. The frequency and dephasing times of the phonons show anomalous temperature dependence below T_SC indicating a coupling of these low energy excitations with the Cooper-pair quasiparticles. A maximum in the amplitude of the acoustic modes at T ~ 170 is seen, attributed to spin fluctuations and strong spin-lattice coupling before T_SDW.Comment: 6 pages, 4 figures (revised manuscript

    Ultrafast quasiparticle dynamics in superconducting iron pnictide CaFe1.89Co0.11As2

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    Nonequilibrium quasiparticle relaxation dynamics is reported in superconducting CaFe1.89Co0.11As2 single crystal using femtosecond time-resolved pump-probe spectroscopy. The carrier dynamics reflects a three-channel decay of laser deposited energy with characteristic time scales varying from few hundreds of femtoseconds to order of few nanoseconds where the amplitudes and time-constants of the individual electronic relaxation components show significant changes in the vicinity of the spin density wave (T_SDW ~ 85 K) and superconducting (T_SC ~ 20 K) phase transition temperatures. The quasiparticles dynamics in the superconducting state reveals a charge gap with reduced gap value of 2Δ\Delta_0/k_BT_SC ~ 1.8. We have determined the electron-phonon coupling constant \lemda to be ~ 0.14 from the temperature dependent relaxation time in the normal state, a value close to those reported for other types of pnictides. From the peculiar temperature-dependence of the carrier dynamics in the intermediate temperature region between the superconducting and spin density wave phase transitions, we infer a temperature scale where the charge gap associated with the spin ordered phase is maximum and closes on either side while approaching the two phase transition temperatures.Comment: 6 pages, 4 figures (revised manuscript); http://dx.doi.org/10.1016/j.ssc.2013.02.00

    Kinetic Investigation of Polyurethane Rubber Formation from CO2‐Containing Polyols

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    A novel CO2 utilization technology allows for the inclusion of CO2 as carbonate units and double bond moieties to give additional functionality in polyether polyols. This study examines the chain‐elongation kinetics of these diols with diisocyanates to polyurethane rubbers by means of thermal analysis. A reaction order of 1 indicates a strong influence of the chains' mobility on the reaction rate. Spectrometry and comparison with non‐double‐bond polyols reveal that the effect cannot be attributed to a substantial occurrence of side reactions but is rather due to the intertwining of lengthy chains.BMBF, 033R350A‐D, Production DreamsTU Berlin, Open-Access-Mittel - 202

    Over-allocation or abatement? : a preliminary analysis of the EU ETS based on the 2005 emission data

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    This paper provides an initial analysis of the EU ETS based on the installation-level data for verified emissions and allowance allocations in the first trading year. Those data, released on May 15, 2006, and subsequent updates revealed that CO2 emissions were about 4% lower than the allocated allowances. The main objective of the paper is to shed light on the extent to which over-allocation and abatement have taken place in 2005. We propose a measure by which over-allocation can be judged and provide estimates of abatement based on emissions data and indicators of economic activity as well as trends in energy and carbon intensity. Finally, we discuss the insights and implications that emerge from this tentative assessment

    Over-Allocation or Abatement? A Preliminary Analysis of the EU Emissions Trading Scheme Based on the 2005 Emissions Data

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    Abstract in HTML and technical report in PDF available on the Massachusetts Institute of Technology Joint Program on the Science and Policy of Global Change website (http://mit.edu/globalchange/www/).This paper provides an initial analysis of the European Union Emissions Trading Scheme (EU ETS) based on the installation-level data for verified emissions and allowance allocations in the first trading year. Those data, released on May 15, 2006, and subsequent updates revealed that CO2 emissions were about 4% lower than the allocated allowances. The main objective of the paper is to shed light on the extent to which over-allocation and abatement have taken place in 2005. We propose a measure by which over-allocation can be judged and provide estimates of abatement based on emissions data and indicators of economic activity as well as trends in energy and carbon intensity. Finally, we discuss the insights and implications that emerge from this tentative assessment.This study received partial support from the MIT Joint Program on the Science and Policy of Global Change, which is supported by a consortium of government, industry and foundation sponsors

    Spin reorientation in Na-doped BaFe2_2As2_2 studied by neutron diffraction

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    We have studied the magnetic ordering in Na doped BaFe2_2As2_2 by unpolarized and polarized neutron diffraction using single crystals. Unlike previously studied FeAs-based compounds that magnetically order, Ba1x_{1-x}Nax_xFe2_2As2_2 exhibits two successive magnetic transitions: For x=0.35 upon cooling magnetic order occurs at \sim70\ K with in-plane magnetic moments being arranged as in pure or Ni, Co and K-doped BaFe2_2As2_2 samples. At a temperature of \sim46\ K a second phase transition occurs, which the single-crystal neutron diffraction experiments can unambiguously identify as a spin reorientation. At low temperatures, the ordered magnetic moments in Ba0.65_{0.65}Na0.35_{0.35}Fe2_2As2_2 point along the cc direction. Magnetic correlations in these materials cannot be considered as Ising like, and spin-orbit coupling must be included in a quantitative theory.Comment: 5 pages, 4 figure

    Cooking and Season as Risk Factors for Acute Lower Respiratory Infections in African Children: A Cross-Sectional Multi-Country Analysis

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    Background Acute lower respiratory infections (ALRI) are a leading cause of death among African children under five. A significant proportion of these are attributable to household air pollution from solid fuel use. Methods We assessed the relationship between cooking practices and ALRI in pooled datasets of Demographic and Health Surveys conducted between 2000 and 2011 in countries of sub-Saharan Africa. The impacts of main cooking fuel, cooking location and stove ventilation were examined in 18 (n = 56, 437),9 (n = 23, 139) and 6 countries (n = 14, 561) respectively. We used a causal diagram and multivariable logistic mixed models to assess the influence of covariates at individual, regional and national levels. Results Main cooking fuel had a statistically significant impact on ALRI risk (p<0.0001),with season acting as an effect modifier (p = 0.034). During the rainy season, relative to clean fuels, the odds of suffering from ALRI were raised for kerosene (OR 1.64;CI: 0.99, 2.71),coal and charcoal (OR 1.54;CI: 1.21, 1.97),wood (OR 1.20;CI: 0.95, 1.51) and lower-grade biomass fuels (OR 1.49;CI: 0.93, 2.35). In contrast, during the dry season the corresponding odds were reduced for kerosene (OR 1.23;CI: 0.77, 1.95),coal and charcoal (OR 1.35;CI: 1.06, 1.72) and lower-grade biomass fuels (OR 1.07;CI: 0.69, 1.66) but increased for wood (OR 1.32;CI: 1.04, 1.66). Cooking location also emerged as a season-dependent statistically significant (p = 0.0070) determinant of ALRI, in particular cooking indoors without a separate kitchen during the rainy season (OR 1.80;CI: 1.30, 2.50). Due to infrequent use in Africa we could, however, not demonstrate an effect of stove ventilation. Conclusions We found differential and season-dependent risks for different types of solid fuels and kerosene as well as cooking location on child ALRI. Future household air pollution studies should consider potential effect modification of cooking fuel by season

    Cooking and Season as Risk Factors for Acute Lower Respiratory Infections in African Children: A Cross-Sectional Multi-Country Analysis

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    Background Acute lower respiratory infections (ALRI) are a leading cause of death among African children under five. A significant proportion of these are attributable to household air pollution from solid fuel use. Methods We assessed the relationship between cooking practices and ALRI in pooled datasets of Demographic and Health Surveys conducted between 2000 and 2011 in countries of sub-Saharan Africa. The impacts of main cooking fuel, cooking location and stove ventilation were examined in 18 (n = 56, 437),9 (n = 23, 139) and 6 countries (n = 14, 561) respectively. We used a causal diagram and multivariable logistic mixed models to assess the influence of covariates at individual, regional and national levels. Results Main cooking fuel had a statistically significant impact on ALRI risk (p<0.0001),with season acting as an effect modifier (p = 0.034). During the rainy season, relative to clean fuels, the odds of suffering from ALRI were raised for kerosene (OR 1.64;CI: 0.99, 2.71),coal and charcoal (OR 1.54;CI: 1.21, 1.97),wood (OR 1.20;CI: 0.95, 1.51) and lower-grade biomass fuels (OR 1.49;CI: 0.93, 2.35). In contrast, during the dry season the corresponding odds were reduced for kerosene (OR 1.23;CI: 0.77, 1.95),coal and charcoal (OR 1.35;CI: 1.06, 1.72) and lower-grade biomass fuels (OR 1.07;CI: 0.69, 1.66) but increased for wood (OR 1.32;CI: 1.04, 1.66). Cooking location also emerged as a season-dependent statistically significant (p = 0.0070) determinant of ALRI, in particular cooking indoors without a separate kitchen during the rainy season (OR 1.80;CI: 1.30, 2.50). Due to infrequent use in Africa we could, however, not demonstrate an effect of stove ventilation. Conclusions We found differential and season-dependent risks for different types of solid fuels and kerosene as well as cooking location on child ALRI. Future household air pollution studies should consider potential effect modification of cooking fuel by season
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