WorldWideScience

Sample records for carbon 14 emission decay

  1. Decay of 226Ra by 14C emission

    International Nuclear Information System (INIS)

    Since the pioneering experiment by Rose and Jones in 1984 demonstrating 14C decay of 223Ra, spontaneous emission of clusters heavier than α particles but lighter than fission products could be found in several cases to be a rare decay mode of heavy nuclei. This new kind of radioactivity has branching ratios relative to α decay well below 10-9. For energetical reasons the emitted fragments are even-even and the daughter nucleus lies close to the doubly magic 208Pb. Polycarbonate track-recording foils which are sensitive to energetic carbon nuclei but not to α particles are very well suited detectors for the study of 14C emission radioactivity. The tracks are made visible under a microscope by etching techniques. Observation of spontaneous emission of 14C from 226Ra claimed by Hourani et al. and Barwick et al. has been confirmed. Since thick sources of 226Ra were used in these experiments the experimental definitions of decay energy and mass were not very accurate. The experiment described in the thesis measured for the first time charge and energy of the emitted fragments by using thin 226Ra sources and polycarbonate track-recording films. The decay mode could thus be identified unambiguously. The track detector was calibrated with tandem-accelerated 14C and 16O ions and tested by observing the now well established 14C emission from 223Ra; for this decay mode a branching ratio of (5,0 ± 1,0).10-10 relative to α decay was found in agreement with values from the literature. In the case of 226Ra the result for 14C/α ratio is (2,3 ± 1,2).10-11. The order of magnitude of the branching ratios can be reproduced by theoretical models. Estimates of partial half-lifes of Ra and other heavy isotopes for rare decay modes are discussed in the theoretical section of the thesis. 100 refs., 3 tabs., 30 figs. (Author)

  2. Searches for massive neutrino emission in 14C beta and 55Fe electron-capture decays

    International Nuclear Information System (INIS)

    In 1985 Simpson reported evidence for the emission of a 17 keV mass neutrino in a small fraction of tritium beta decays. An experimental controversy ensued in which a number of both positive and negative results were reported. The beta spectrum of 14C was collected in a unique 14C-doped planar germanium detector and a distortion was observed that initially confirmed Simpson's result. Further tests linked this distortion to a splitting of the collected charge between the central detector and the surrounding guard ring in a fraction of the events. A second 14C measurement showed no evidence for emission of a 17 keV mass neutrino. In a related experiment, a high statistics electron-capture internal-bremsstrahlung photon spectrum of 55Fe was collected with a coaxial germanium detector. A local search for departures from a smooth shape near the endpoint was performed, using a second-derivative technique. An upper limit of 0.65% (95% C.L.) for the mixing Of a neutrino in the mass range 5--25 keV was established. The upper limit on the mixing of a 17 keV mass neutrino was 0.14% (95% C.L.)

  3. Evidence for the emission of a 17-keV neutrino in the β decay of 14C

    International Nuclear Information System (INIS)

    We have studied the β spectrum of 14C using a germanium detector containing a crystal with 14C dissolved in it. We find a feature in the β spectrum 17 keV below the end point which can be explained by the hypothesis that there is a heavy neutrino emitted in the β decay of 14C with a mass of 17±2 keV and an emission probability of (1.40±0.45±0.14)%

  4. Nuclear Structure Effects in the Exotic Decay of $^{225}$Ac via $^{14}$C Emission

    CERN Multimedia

    2002-01-01

    % IS323 \\\\ \\\\ We propose to build at Isolde a high intensity $^{225}$Ac source by $\\beta$-decay of $^{225}$(Ra+Fr) beam, to be used at the superconducting spectrometer SOLENO of IPN-Orsay in order to study a possible fine structure in the spectrum of $^{14}$C ions spontaneously emitted by $^{225}$Ac.

  5. Searches for massive neutrino emission in {sup 14}C beta and {sup 55}Fe electron-capture decays

    Energy Technology Data Exchange (ETDEWEB)

    Wietfeldt, F.E. [California Univ., Berkeley, CA (United States). Dept. of Physics]|[Lawrence Berkeley Lab., CA (United States)

    1994-05-01

    In 1985 Simpson reported evidence for the emission of a 17 keV mass neutrino in a small fraction of tritium beta decays. An experimental controversy ensued in which a number of both positive and negative results were reported. The beta spectrum of {sup 14}C was collected in a unique {sup 14}C-doped planar germanium detector and a distortion was observed that initially confirmed Simpson`s result. Further tests linked this distortion to a splitting of the collected charge between the central detector and the surrounding guard ring in a fraction of the events. A second {sup 14}C measurement showed no evidence for emission of a 17 keV mass neutrino. In a related experiment, a high statistics electron-capture internal-bremsstrahlung photon spectrum of {sup 55}Fe was collected with a coaxial germanium detector. A local search for departures from a smooth shape near the endpoint was performed, using a second-derivative technique. An upper limit of 0.65% (95% C.L.) for the mixing Of a neutrino in the mass range 5--25 keV was established. The upper limit on the mixing of a 17 keV mass neutrino was 0.14% (95% C.L.).

  6. Chemical separation of carbon -14 in radwastes

    International Nuclear Information System (INIS)

    Carbon-14 has a long half-life of 5730 years and decays by beta emission of 156KeV to the stable nuclide, Nitrogen-14. Carbon-14 is produced mostly by the neutron activation of naturally occurring oxygen-17 in water molecules of the reactor coolant and Nitrogen-14 from nitrogen gas dissolved in the reactor coolant. Most of these carbon-14 are known to be discharged as gaseous wastes. The chemical forms of the gaseous emissions of carbon-14 from PWR stations range from 10∼26% as 14CO2 and 74∼90% as 14CH4 and other hydrocarbons, compared to about 95% as 14CO2 and 5% as 14CH4 and other hydrocarbons in BWR station gaseous emissions. Knowles reported that although the exact nature of these organic compounds was not identified, most of the carbon-14 was present as forms of organic species in a PWR primary coolant. Praudic measured the contents of the total organic and inorganic carbon-14 in waste trench leachates of New York commercial LLW disposal site and found that 74 ∼ 98% of carbon-14 was organic. In 1991, Dayal and Kirby reported that carbon-14 identified in LLW trench leachates from the Maxi Fiats site were carbonate and bicarbonate as inorganic carbon-14 and citric acid and palmitic acid as organic carbon-14. Thus concentrated Boric acid waste solutions(CB) which has generated from domestic NPP were classified into organic and inorganic carbon-14 with wet oxidation method in order to grasping a existing ratio of organic carbon-14 from total one due to affecting an environment

  7. Carbon-14 based determination of the biogenic fraction of industrial CO2 emissions : Application and validation

    NARCIS (Netherlands)

    Palstra, S. W. L.; Meijer, H. A. J.

    2010-01-01

    The C-14 method is a very reliable and sensitive method for industrial plants, emission authorities and emission inventories to verify data estimations of biogenic fractions of CO2 emissions. The applicability of the method is shown for flue gas CO2 samples that have been sampled in I-h intervals at

  8. Constraints on emissions of carbon monoxide, methane, and a suite of hydrocarbons in the Colorado Front Range using observations of 14CO2

    OpenAIRE

    LaFranchi, B. W; Pétron, G.; Miller, J. B.; S. J. Lehman; Andrews, A. E; E. J. Dlugokencky; Hall, B.; Miller, B. R.; Montzka, S. A.; W. Neff; P. C. Novelli; C. Sweeney; J. C. Turnbull; D. E. Wolfe; P. P. Tans

    2013-01-01

    Atmospheric radiocarbon (14C) represents an important observational constraint on emissions of fossil-fuel derived carbon into the atmosphere due to the absence of 14C in fossil fuel reservoirs. The high sensitivity and precision that accelerator mass spectrometry (AMS) affords in atmospheric 14C analysis has greatly increased the potential for using such measurements to evaluate bottom-up emissions inventories of fossil fuel CO2 (CO2ff), as well as those for other co-emitte...

  9. Carbon-14 waste management

    International Nuclear Information System (INIS)

    Carbon-14 occurs in nature, but is also formed in nuclear reactors. Because of its long half-life and the biological significance of carbon, releases from nuclear facilities could have a significant radiological impact. Waste management strategies for carbon-14 are therefore of current concern. Carbon-14 is present in a variety of waste streams both at reactors and at reprocessing plants. A reliable picture of the production and release of carbon-14 from various reactor systems has been built up for the purposes of this study. A possible management strategy for carbon-14 might be the reduction of nitrogen impurity levels in core materials, since the activation of 14N is usually the dominant source of carbon-14. The key problem in carbon-14 management is its retention of off-gas streams, particularly in the dissolver off-gas stream at reprocessing plants. Three alternative trapping processes that convert carbon dioxide into insoluble carbonates have been suggested. The results show that none of the options considered need be rejected on the grounds of potential radiation doses to individuals. All exposures should be as low as reasonably achievable, economic and social factors being taken into account. If, on these grounds, retention and disposal of carbon-14 is found to be beneficial, then, subject to the limitations noted, appropriate retention, immobilization and disposal technologies have been identified

  10. The Carbon Emission Game

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    When Chinese President Hu Jintao attended the UN climate summit on September22,he made a solemn commitment that China will cut its per GDP unit carbon emission to a significant amount in 2020 compared with that of 2005.

  11. Constraints on emissions of carbon monoxide, methane, and a suite of hydrocarbons in the Colorado Front Range using observations of 14CO2

    Directory of Open Access Journals (Sweden)

    P. P. Tans

    2013-01-01

    Full Text Available Atmospheric radiocarbon (14CO represents an important observational constraint on emissions of fossil-fuel derived carbon into the atmosphere due to the absence of 14CO in fossil fuel reservoirs. The high sensitivity and precision that accelerator mass spectrometry (AMS affords in atmospheric 14CO analysis has greatly increased the potential for using such measurements to evaluate bottom-up emissions inventories of fossil fuel CO2 (CO2ff, as well as those for other co-emitted species. Here we use observations of 14CO2 and a series of hydrocarbons and combustion tracers from discrete air samples collected between June 2009 and September 2010 at the National Oceanic and Atmospheric Administration Boulder Atmospheric Observatory (BAO; Lat: 40.050° N, Lon: 105.004° W to derive emission ratios of each species to CO2ff. From these emission ratios, we estimate emissions of these species by using the Vulcan CO2ff high resolution data product as a reference. The species considered in this analysis are carbon monoxide (CO, methane (CH4, acetylene (C2H2, benzene (C6H6, and C3–C5 alkanes. Comparisons of top-down emissions estimates are made to existing inventories of these species for Denver and adjacent counties, as well as to previous efforts to estimate emissions from atmospheric observations over the same area. We find that CO is overestimated in the 2008 National Emissions Inventory (NEI, 2008 by a factor of ~2. A close evaluation of the inventory suggests that the ratio of CO emitted per unit fuel burned from on-road gasoline vehicles is likely over-estimated by a factor of 2.5. The results also suggest that while the oil and gas sector is the largest contributor to the CH4 signal in air arriving from the north and east, it is very likely that other sources, including agricultural sources, contribute to this signal and must be accounted for when attributing these signals to oil and gas industry activity from a top-down perspective. Our results are

  12. Carbon emissions control strategies

    International Nuclear Information System (INIS)

    This study was undertaken to address a fundamental issue: the cost of slowing climate change. Experts in eight nations were asked to evaluate, using the best economic models available, the prospects for reducing fossil fuel-based carbon emissions in their respective nations. The nations selected as case studies include: the Soviet Union, Poland, the United States, Japan, Hungary, France, the United Kingdom, and Canada. As important contributors to the greenhouse effect, these industrialized nations must find ways to substantially reduce their emissions. This is especially critical given that developing nations' emissions are expected to rise in the coming decades in the search for economic development. Ten papers have been processed separately for inclusion in the appropriate data bases

  13. Compilation of carbon-14 data

    International Nuclear Information System (INIS)

    A review and critical analysis was made of the original sources of carbon-14 in the graphite moderator and reflector zones of the eight Hanford production reactors, the present physical and chemical state of the carbon-14, pathways (other than direct combustion) by which the carbon-14 could be released to the biosphere, and the maximum rate at which it might be released under circumstances which idealistically favor the release. Areas of uncertainty are noted and recommendations are made for obtaining additional data in three areas: (1) release rate of carbon-14 from irradiated graphite saturated with aerated water; (2) characterization of carbon-14 deposited outside the moderator and reflector zones; and (3) corrosion/release rate of carbon-14 from irradiated steel and aluminum alloys

  14. The Uncertain Carbon Emissions in China (Invited)

    Science.gov (United States)

    Liu, Z.; Guan, D.

    2013-12-01

    Anthropogenic fossil fuel emissions are considered as being well understood with a low uncertainty (9.1 × 0.5Gt C yr-1). By using full transparency emission inventory which the energy consumption, fuel heating values, carbon content and oxidation rate reported separately in sectoal level, here we found new 2.1 Gt C yr-1 (23% of global total) uncertainties of carbon emission inventory, which mainly contributed by the mass energy use and consumption coal quality in China and by misunderstanding of fuel quality in international fossil fuel trade. Increment of coal's carbon emission in China and India are equivalent to 130 % of global total coal's emission growth during 2008-2010, by using macro energy statistics and bottom up coal mine datasets, the difference carbon emission estimates from China and India can up to 1.32 C yr-1. Emissions from international trade of coal could produce another 0.08 Gt C yr-1 uncertainty. These new emerging 1.4 Gt C yr-1 uncertainties implies a significant mis-estimation of human induced carbon emissions and a new dominating factor in contributing the global carbon budget residual.

  15. To decay or not to decay - or both ! quantum mechanics of spontaneous emission

    DEFF Research Database (Denmark)

    Kristensen, Philip Trøst; Lodahl, Peter; Mørk, Jesper

    2008-01-01

    We discuss calculations of spontaneous emission from quantum dots in photonic crystals and show how the decay depends on the intrinsic properties of the emitter as well as the position. A number of fundamentally different types of spontaneous decay dynamics are shown to be possible, including...... counter intuitive situations in which the quantum dot decays only partially....

  16. Carbon emissions and income inequality

    International Nuclear Information System (INIS)

    We find that the distribution of income matters to aggregate carbon dioxide emissions and hence global warming. Higher inequality, both between and within countries is associated with lower carbon emissions at given average incomes. We also confirm that economic growth generally comes with higher emissions. Thus our results suggest that trade-offs exist between climate control (on the one hand) and both social equity and economic growth (on the other). However, economic growth improves the trade off with equity, and lower inequality improves the trade off with growth. By combining growth with equity, more pro-poor growth processes yield better longer-term trajectories of carbon emissions. (Author)

  17. Carbon 14 dating method

    International Nuclear Information System (INIS)

    This document gives a first introduction to 14C dating as it is put into practice at the radiocarbon dating centre of Claude-Bernard university (Lyon-1 univ., Villeurbanne, France): general considerations and recalls of nuclear physics; the 14C dating method; the initial standard activity; the isotopic fractioning; the measurement of samples activity; the liquid-scintillation counters; the calibration and correction of 14C dates; the preparation of samples; the benzene synthesis; the current applications of the method. (J.S.)

  18. Carbon-14 transfer into potato plants following a short exposure to an atmospheric 14CO2 emission: observations and model predictions.

    Science.gov (United States)

    Melintescu, A; Galeriu, D; Tucker, S; Kennedy, P; Siclet, F; Yamamoto, K; Uchida, S

    2013-01-01

    To improve the understanding of the environmental (14)C behaviour, the International Atomic Energy Agency (IAEA) coordinated a Tritium and C-14 Working Group (T&C WG) in its EMRAS (Environmental Modelling for Radiation Safety) programme. One of the scenarios developed in the frame of T&C WG involved the prediction of time dependent (14)C concentrations in potato plants. The experimental data used in the scenario were obtained from a study in which potatoes (Solanum tuberosum cv. Romano) were exposed to atmospheric (14)CO(2) in a wind tunnel. The observations were used to test models that predict temporal changes in (14)C concentrations in leaves at each sampling time for each experiment and (14)C concentrations in tubers at the final harvest of each experiment. The experimental data on (14)C dynamics in leaves are poorly reproduced by most of the models, but the predicted concentrations in tubers are in good agreement with the observations. PMID:22995861

  19. Two-proton emission in the decay of 31Ar

    International Nuclear Information System (INIS)

    Several beta-delayed two-proton branches were observed in the decay of 31Ar, the most intense ones proceeding through the isobaric analogue state (IAS) in 31Cl. The mechanism of the two-proton emission is studied via the energy and angular distributions of the two protons. Simultaneous emission of the two protons fits the present data well, sequential decays might also describe them. Independent of the decay mechanism, a spin of 5/2 for the IAS is suggested. An improved limit on the direct two-proton emission from the ground state of 31Ar is presented. (orig.)

  20. Energy of the 14O superallowed positron decay

    International Nuclear Information System (INIS)

    The threshold energy of the 14N(p,n)14O reaction has been measured to be 6354.35(18) keV relative to a 1-V standard, and an earlier value has been withdrawn. This leads to a Qec value for the superallowed positron decay of 14O of 2831.53(17) keV and a recommended mean value of Qec=2831.47(14) keV

  1. Carbon-14 in tree rings

    International Nuclear Information System (INIS)

    In order to investigate how reliably the carbon 14 content of tree rings reflects that of atmospheric carbon dioxide, two types of determinations were carried out: (1) carbon 14 determinations in annual rings from the beginning of this century until 1974 and (2) carbon 14 determinations in synchronous wood from the North American bristlecone pine and from European oak trees, dendrochronologically dated to have grown in the third and fourth century B.C. The first series of measurements showed that bomb-produced radiocarbon was incorporated in wood at a time when it was converted from sapwood to heartwood, whenever radiocarbon from bomb testing was present in the atmosphere. The second series showed that wood more than 2000 years old and grown on two different continents at different altitudes had, within the limits of experimental error, the same radiocarbon content. This work and other experimental evidence, obtained in part by other laboratories, show that tree rings reflect the average radiocarbon content of global atmospheric carbon dioxide accurately within several parts per mil. In rare cases, deviations of up to 10 parts per thousand may be possible. This means that a typical single radiocarbon date for wood or charcoal possesses an intrinsic uncertainty (viz., an estimated ''one-sigma error'' in addition to all the other errors) of the order of +-50 years. This intrinsic uncertainty is independent of the absolute age of the sample. More accurate dates can, in principle, be obtained by the so-called method of ''wiggle matching.''

  2. Controlling carbon emissions in China

    International Nuclear Information System (INIS)

    We examine the use of carbon taxes to reduce emissions of CO2 in China. To do so, we develop a dynamic computable general equilibrium (CGE) model of the Chinese economy. In addition to accounting for the effects of population growth, capital accumulation, technological change, and changing patterns of demand, we also incorporate into our model elements of the dual nature of China's economy where both plan and market institutions exist side by side. We conduct simulations in which carbon emissions are reduced by 5, 10, and 15 per cent from our baseline. After initial declines, in all of our simulations GDP and consumption rapidly exceed baseline levels as the revenue neutral carbon tax serves to transfer income from consumers to producers and then into increased investment. Although subject to a number of caveats, we find potential for what is in some sense a double dividend, a decrease in emissions for CO2 and a long run increase in GDP and consumption. (Author)

  3. Secondary emission influenced fluorescence decay of a homogeneous fluorophore solution

    International Nuclear Information System (INIS)

    An analytical expression is found allowing the calculation of the secondary emission influenced fluorescence decay of a homogeneous fluorophore solution. Before starting the calculation one has to know the shape of the primary fluorescence decay of the fluorophore and the value of the parameter κ denoting the ratio of the secondary to primary steady-state fluorescence intensities. The method elaborated by Budó and Ketskeméty is recommended for evaluation of the parameter κ. The main importance of the obtained expression is that it can be used to recover parameters characterizing the fluorescence decay in the absence of secondary emission. The cases of monoexponential, biexponential and multiexponential primary fluorescence decays are discussed in detail. (paper)

  4. Free allocations in EU ETS Phase 3: The impact of emissions performance benchmarking for carbon-intensive industry - Working Paper No. 2013-14

    International Nuclear Information System (INIS)

    From Phase 3 (2013-20) of the European Union Emissions Trading Scheme, carbon-intensive industrial emitters will receive free allocations based on harmonised, EU-wide benchmarks. This paper analyses the impacts of these new rules on allocations to key energy-intensive sectors across Europe. It explores an original dataset that combines recent data from the National Implementing Measures of 20 EU Member States with the Community Independent Transaction Log and other EU documents. The analysis reveals that free allocations to benchmarked sectors will be reduced significantly compared to Phase 2 (2008-12). This reduction should both increase public revenues from carbon auctions and has the potential to enhance the economic efficiency of the carbon market. The analysis also shows that changes in allocation vary mostly across installations within countries, raising the possibility that the carbon-cost competitiveness impacts may be more intense within rather than across countries. Lastly, the analysis finds evidence that the new benchmarking rules will, as intended, reward installations with better emissions performance and will improve harmonisation of free allocations in the EU ETS by reducing differences in allocation levels across countries with similar carbon intensities of production. (authors)

  5. Exciton decay dynamics in individual carbon nanotubes at room temperature

    OpenAIRE

    Gokus, Tobias; Hartschuh, Achim; Harutyunyan, Hayk; Allegrini, Maria; Hennrich, Frank; Kappes, Manfred; Green, Alexander A.; Hersam, Mark C.; Araujo, Paulo T.; Jorio, Ado

    2008-01-01

    We studied the exciton decay dynamics of individual semiconducting single-walled carbon nanotubes at room temperature using time-resolved photoluminescence spectroscopy. The photoluminescence decay from nanotubes of the same (n,m) type follows a single exponential decay function, however, with lifetimes varying between about 1 and 40 ps from nanotube to nanotube. A correlation between broad photoluminescence spectra and short lifetimes was found and explained by defects promoting both nonradi...

  6. Evidence for the emission of a massive neutrino in nuclear beta decay

    International Nuclear Information System (INIS)

    We have studied the β-spectrum of 14C using a germanium detector containing a crystal with 14C dissolved in it. We find a feature in the β-spectrum 17 keV below the endpoint which can be explained by the hypothesis that there is a heavy neutrino emitted in the β-decay of 14C with a mass of 17 ± 2 keV and an emission probability of 1.40 ± 0.45%. In addition, we have studied the inner bremsstrahlung spectrum of 55Fe and also find indications of the emission of a ∼ 17-keV neutrino. These results are consistent with observations of similar anomalies in the β-decays of 3H and 35S. 29 refs., 7 figs

  7. Carbon emissions of infrastructure development.

    Science.gov (United States)

    Müller, Daniel B; Liu, Gang; Løvik, Amund N; Modaresi, Roja; Pauliuk, Stefan; Steinhoff, Franciska S; Brattebø, Helge

    2013-10-15

    Identifying strategies for reconciling human development and climate change mitigation requires an adequate understanding of how infrastructures contribute to well-being and greenhouse gas emissions. While direct emissions from infrastructure use are well-known, information about indirect emissions from their construction is highly fragmented. Here, we estimated the carbon footprint of the existing global infrastructure stock in 2008, assuming current technologies, to be 122 (-20/+15) Gt CO2. The average per-capita carbon footprint of infrastructures in industrialized countries (53 (± 6) t CO2) was approximately 5 times larger that that of developing countries (10 (± 1) t CO2). A globalization of Western infrastructure stocks using current technologies would cause approximately 350 Gt CO2 from materials production, which corresponds to about 35-60% of the remaining carbon budget available until 2050 if the average temperature increase is to be limited to 2 °C, and could thus compromise the 2 °C target. A promising but poorly explored mitigation option is to build new settlements using less emissions-intensive materials, for example by urban design; however, this strategy is constrained by a lack of bottom-up data on material stocks in infrastructures. Infrastructure development must be considered in post-Kyoto climate change agreements if developing countries are to participate on a fair basis. PMID:24053762

  8. China's Carbon Emissions 1971-2003

    OpenAIRE

    Chunbo Ma; Stern, David I.

    2007-01-01

    A number of previous studies on China's carbon emissions have mainly focused on two facts: 1) the continuous growth in emissions up till the middle of the 1990s; 2) the recent stability of emissions from 1996 to 2001. Decomposition analysis has been widely used to explore the driving forces behind these phenomena. However, since 2002, China's carbon emissions have resumed their growth at an even greater rate. This paper investigates China's carbon emissions during 1971-2003, with particular f...

  9. An explanation of carbon emission markets

    International Nuclear Information System (INIS)

    After having outlined the necessity to drastically reduce anthropic carbon emissions, and discussed how to associate standards, taxes and quota markets, the authors describe how carbon emission markets have emerged: the Kyoto protocol, the emission trade scheme (ETS) of the European Union, other carbon markets (existing or in preparation). They introduce and present four pillars of carbon emission markets: the allocation process, the reliability of emission measurement and control, market records and transparency, and introduction of flexibility. They examine the possibility of success in the development of a greenhouse gas emission market. The authors discuss the problems raised by a design of carbon markets by government and their use by private actors, how to connect existing or future regional carbon markets, the integration of forest and agriculture through new compensatory mechanisms, how to face carbon leaks by widening carbon markets

  10. The carbon emissions of Chinese cities

    OpenAIRE

    Wang, H.; Bi, J.; Zhang, R.; Liu, M.

    2012-01-01

    As increasing urbanization has become a national policy priority for economic growth in China, cities have become important players in efforts to reduce carbon emissions. However, their efforts have been hampered by the lack of specific and comparable carbon emission inventories. Comprehensive carbon emission inventories, which present both a relatively current snapshot and also show how emissions have changed over the past several years, of twelve Chinese cities were developed using ...

  11. The carbon emissions of Chinese cities

    OpenAIRE

    Wang, H.; Zhang, R.; Liu, M.; Bi, J.

    2012-01-01

    As increasing urbanization has become a national policy priority for economic growth in China, cities have become important players in efforts to reduce carbon emissions. However, their efforts have been hampered by the lack of specific and comparable carbon emission inventories. Comprehensive carbon emission inventories for twelve Chinese cities, which present both a relatively current snapshot and also show how emissions have changed over the past several years, were devel...

  12. Anorganic fluorescence reference materials for decay time of fluorescence emission

    Science.gov (United States)

    Engel, A.; Ottermann, C.; Klahn, J.; Korb, T.; Resch-Genger, U.; Hoffmann, K.; Kynast, U.; Rupertus, V.

    2008-02-01

    Fluorescence techniques are known for their high sensitivity and are widely used as analytical tools, detection methods and imaging applications for product and process control, material sciences, environmental and bio-technical analysis, molecular genetics, cell biology, medical diagnostics, and drug screening. According to DIN/ISO 17025 certified standards are used for steady state fluorescence diagnostics, a method having the drawback of giving relative values for fluorescence intensities only. Therefore reference materials for a quantitative characterization have to be related directly to the materials under investigation. In order to evaluate these figures it is necessary to calculate absolute numbers such as absorption/excitation cross sections and quantum yield. This has been done for different types of dopands in different materials such as glass, glass ceramics, crystals or nano crystalline material embedded in polymer matrices. Samples doped with several fluophores of different emission wavelengths and decay times are required for fluorescent multiplexing applications. Decay times shorter than 100 ns are of special interest. In addition, a proper knowledge is necessary of quantum efficiency in highly scattering media. Recently, quantum efficiency in YAG:Ce glass ceramics has been successfully investigated. Glass and glass ceramics doped with threefold charged rare earth elements are available. However, these samples have the disadvantage of emission decay times much longer than 1 microsecond, due to the excitation and emission of their optical forbidden electronic transitions. Therefore first attempts have been made to produce decay-time standards based on organic and inorganic fluophores. Stable LUMOGEN RED pigments and YAG:Ce phosphors are diluted simultaneously in silicone matrices using a wide range of concentrations between 0.0001 and 2 wt%. Organic LUMOGEN RED has decay times in the lower nanosecond range with a slight dependency on concentration

  13. Exotic decay in Ba isotopes via 12C emission

    Indian Academy of Sciences (India)

    K P Santhosh; Antony Joseph

    2000-09-01

    Considering Coulomb and proximity potentials as barriers, we have calculated the half lives for 12C emission from various Ba isotopes using different mass tables. The half life for 112Ba isotope calculated by us is 6.020 × 103 s which is comparable with the experimental value 5.620 × 103 s. From our study it is found that 114Ba is the good parent for 12C emission whose emission rate is favorable for measurement. The half lives predicted by us lie very close to those reported by Shanmugam et al using their cubic plus Yukawa plus exponential model. It is observed that inclusion of proximity potential does not produce significant deviation from the linear nature of the Geiger–Nuttall plots. Also it is found that the neutron excess in the parent nuclei slows down the exotic decay process.

  14. Carbon-14 Bomb-Pulse Dating

    Energy Technology Data Exchange (ETDEWEB)

    Buchholz, B A

    2007-12-16

    Atmospheric testing of nuclear weapons during the 1950s and early 1960s doubled the concentration of carbon-14 atmosphere and created a pulse that labeled everything alive in the past 50 years as carbon moved up the food chain. The variation in carbon-14 concentration in time is well-documented and can be used to chronologically date all biological materials since the mid-1950s.

  15. Decaying cyanobacteria decrease N2O emissions related to diversity of intestinal denitrifiers of Chironomus plumosus

    Directory of Open Access Journals (Sweden)

    Xu Sun

    2014-10-01

    Full Text Available Nitrous oxide (N2O emission of fresh invertebrates has too long been neglected in eutrophic lakes, although the sediments these animals inhabit are presumably hot spots of N2O emission. Thus, the experiment in this research was designed to gain insight into the influence of cyanobacterial degradation on the N2O emission by fresh water invertebrates (Chironomus plumosus. The presence of decaying cyanobacteria in Lake Taihu decreased the N2O emission rate of Chironomus plumosus larvae from the larvae body by almost 400% for the larvae as a whole. The N2O emission rate decreased by 350% based on readings from studies of their gut, which was mostly due to stimulation of intestinal complete denitrification. The quantitative PCR results showed that intestinal gene abundance of nirK, nosZ (encoding the copper nitrite reductase and N2O reductase, respectively were significantly increased with the presence of decaying cyanobacteria. In contrast nirS (encoding the cytochrome cd1 heme nitrite reductase and the total bacteria decreased. In the gut of Chironomus plumosus, the diversity and richness of nosZ and nirK were lower with the cyanobacteria. Phylogenetic analysis of the intestinal function genes (nosZ and nirK showed that the nosZ- and nirK-type denitrifying bacterial sequences were related to different phylotypes. Hence, additional cyanobacteria increased the abundance, but decreased the richness and diversity of intestinal nitrate-reducing bacteria, probably by providing more carbon source in the gut. The data obtained in this study elucidates that the decaying cyanobacteria decreased the emissions of N2O by the aquatic invertebrates in freshwater sediment and could serve as a valuable resource for nitrogen removal affecting greenhouse gas emissions.

  16. The carbon emissions of Chinese cities

    Directory of Open Access Journals (Sweden)

    H. Wang

    2012-03-01

    Full Text Available As increasing urbanization has become a national policy priority for economic growth in China, cities have become important players in efforts to reduce carbon emissions. However, their efforts have been hampered by the lack of specific and comparable carbon emission inventories. Comprehensive carbon emission inventories, which present both a relatively current snapshot and also show how emissions have changed over the past several years, of twelve Chinese cities were developed using bottom-up approach. Carbon emissions in most of Chinese cities rose along with economic growth from 2004 to 2008. Yet per capita carbon emissions varied between the highest and lowest emitting cities by a factor of nearly 7. Average per capita carbon emissions varied across sectors, including industrial energy consumption (64.3%, industrial processes (10.2%, transportation (10.6%, household energy consumption (8.0%, commercial energy consumption (4.3% and waste processing (2.5%. The levels of per capita carbon emissions in China's cities were higher than we anticipated before comparing them with the average of global cities. This is mainly due to the major contribution of industry sector encompassing industrial energy consumption and industrial processes to the total carbon emissions of Chinese cities.

  17. Carbon-14 dating with the 14UD accelerator

    International Nuclear Information System (INIS)

    A carbon-14 accelerator mass spectroscopy system is now in routine operation on the 14UD accelerator. It offers a modest precision of ∼ 3% for samples that are >10% modern. Its performances and some of recent applications are briefly discussed

  18. The carbon 14 and environment; Le carbone 14 et l'environnement

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2007-07-01

    This article resume the history and the properties of the carbon 14 ({sup 14}C). We also find the different origins and the produced quantities. The carbon transfers in environment are explained and so the {sup 14}C. The biological effects and the sanitary aspects are clarified. The measurements of carbon 14 are given as well its application through the dating. The waste management is tackled. (N.C.)

  19. Exoelectron Emission of a Carbon Nanomaterial

    Science.gov (United States)

    Kortov, V. S.; Slesarev, A. I.; Tkachev, A. G.

    2008-03-01

    The exoemission properties of a Taunite carbon nanomaterial consisting of nanosized multiwalled nanotubes and nanofibers were investigated by thermally stimulated exoelectron emission (TSEE). The TSEE spectra of the carbon nanomaterial differed from the spectra of pressed graphite. It was assumed that defect—adsorbate complexes were emission-active centers on the surface of the nanomaterial

  20. Decay of cacti and carbon cycling

    Science.gov (United States)

    Garvie, Laurence A. J.

    2006-03-01

    Cacti contain large quantities of Ca-oxalate biominerals, with C derived from atmospheric CO2. Their death releases these biominerals into the environment, which subsequently transform to calcite via a monohydrocalcite intermediate. Here, the fate of Ca-oxalates released by plants in arid environments is investigated. This novel and widespread form of biomineralization has unexpected consequences on C cycling and calcite accumulation in areas with large numbers of cacti. The magnitude of this mineralization is revealed by studying the large columnar cactus Carnegiea gigantea (Engelm.) Britton and Rose in southwestern Arizona (locally called the saguaro). A large C. gigantea contains on the order of 1×105 g of the Ca-oxalate weddellite—CaC2O4·2H2O. In areas with high C. gigantea density, there is an estimated 40 g Catm m-2 sequestered in Ca-oxalates. Following the death of the plant, the weddellite transforms to calcite on the order to 10-20 years. In areas with high saguaro density, there is an estimated release of up to 2.4 g calcite m-2 year-1 onto the desert soil. Similar transformation mechanisms occur with the Ca-oxalates that are abundant in the majority of cacti. Thus, the total atmospheric C returned to the soil of areas with a high number density of cacti is large, suggesting that there may be a significant long-term accumulation of atmospheric C in these soils derived from Ca-oxalate biominerals. These findings demonstrate that plant decay in arid environments may have locally significant impacts on the Ca and inorganic C cycles.

  1. Carbon emissions and an equitable emission reduction criterion

    International Nuclear Information System (INIS)

    In 1995 the world-wide carbon emissions reached 5.8 billion metric tonnes per year (GTC/y). The Kyoto protocol calls for a reduction of carbon emissions from the developed countries (Annex I countries) of 6-8% below 1990 levels on the average, and unspecified commitments for the less developed (non-Annex I) countries. It is doubtful that the Kyoto agreement will be ratified by some parliaments, especially the USA Congress. Furthermore, it is shown that if the non-Annex I countries will not curtail their carbon emissions drastically, the global emissions will soar to huge levels by the middle of the next century. An equitable emission criterion is proposed which may lead to a sustainable rate of growth of carbon emissions, and be acceptable to all countries of the world. The criterion links the rate of growth of carbon emissions to the rate of growth of the Gross Domestic Product (GDP). A target criterion is proposed R = 0.15 KgC/SGDP, which is the current average for western European countries and Japan. This allows for both the growth of the GDP and carbon emissions. However, to reach the target in a reasonable time, the countries for which R≤ 0.3 would be allowed a carbon emission growth rate of 1%./y, and countries for which R≥ 0.3, 0.75%/y. It is shown that by 2050 the world-wide carbon emissions would reach about 10 GTC/y, which is about 3 times less than the Kyoto agreement would allow. (Author)

  2. Carbon dioxide and methane emissions from estuaries

    OpenAIRE

    Abril, G.; Borges, Alberto

    2005-01-01

    Carbon dioxide and methane emissions from estuaries are reviewed in relationwith biogeochemical processes and carbon cycling. In estuaries, carbondioxide and methane emissions show a large spatial and temporalvariability, which results from a complex interaction of river carbon inputs,sedimentation and resuspension processes, microbial processes in watersand sediments, tidal exchanges with marshes and flats and gas exchangewith the atmosphere. The net mineralization of land-derived organic ca...

  3. Carbon 14 and tritium radioactivity of alcohols

    International Nuclear Information System (INIS)

    The method of measuring carbon 14 radioactivity of alcohols has been perfected in order to establish the correct determination of synthetic alcohol added to fermentation alcohol. The specific carbon and tritium activity of alcohol of different origins have been determined for 1973 and 1974. The Suess effect and nuclear fall-out are observed

  4. MODIFYING V-14 RUBBER WITH CARBON FIBERS

    OpenAIRE

    Shadrinov N. V.; Nartakhova S. I.

    2016-01-01

    The influence of carbon fibers and modified carbon fibers on properties of industrially produced V-14 rubber is examined. The dependences of physical and mechanical properties, hardness, abrasion resistance and resistance in aggressive environment on few amount of filled fiber are established. Structural properties of reinforced elastomeric composites are studied by scanning electron microscopy. Elastomeric layer on the surface of modified carbon fiber, confirmed with high adhesion is identified

  5. Carbon-14 measurements in aquifers with methane

    International Nuclear Information System (INIS)

    A survey of various groundwater systems indicates that methane is a common trace constituent and occasionally a major carbon species in groundwaters. Thermocatalytic methane had delta13Csub(CH4)>-45 per mille and microbially produced or biogenic methane had delta13Csub(CH4)13C values for the inorganic carbon. Thermocatalytic methane had no apparent effect on the inorganic carbon. Because methanogenesis seriously affects the carbon isotope geochemistry of groundwaters, the correction of raw 14C ages of affected groundwaters must consider these effects. Conceptual models are developed which adjust the 14C activity of the groundwater for the effects of methanogenesis and for the dilution of carbon present during infiltration by simple dissolution of rock carbonate. These preliminary models are applied to groundwaters from the Alliston sand aquifer where methanogenesis has affected most samples. In this system, methanogenic bacteria using organic matter present in the aquifer matrix as substrate have added inorganic carbon to the groundwater which has initiated further carbonate rock dissolution. These processes have diluted the inorganic carbon 14C activity. The adjusted groundwater ages can be explained in terms of the complex hydrogeology of this aquifer, but also indicate that these conceptual models must be more rigorously tested to evaluate their appropriateness. (author)

  6. Bond Rupture following C14 and T3 Beta Decay

    International Nuclear Information System (INIS)

    As a result of nuclear transformations an atom acquires a recoil energy, and a portion of this energy becomes associated with the chemical bond or bonds joining the activated atom to the molecule. Usually sufficient energy is deposited in these bonds to permit the activated atom to dissociate from the remainder of the molecule. Bond-rupture, however, usually does not occur with 100% efficiency. Momentum transfer to an atom in a molecule (internal excitation and bond-rupture) have been discussed recently with reference to activation of atoms joined to a molecule by only one bond. Additional molecules are considered in the present paper, and data presented on the net recoil energy required for bond- rupture, the rotational and vibrational excitation energies received by the rupturing bond, the internal energy of the radical originally bonded to the activated atom, and the kinetic energy of the radicals. It is shown that, on the average, the recoil energy that must be acquired by the activated atom in order to rupture from the molecule is about 25% greater than that calculated assuming a pseudo-diatomic molecule. Data are also presented for certain C14 and T3 beta-decay recoil processes. For C14O2 it is calculated that a net N14 recoil energy s 1.92 times the ON-O+ bond dissociation energy is required for bond-rupture. Since the NO+2 product may possess about 0.6 to 1.0 eV of electronic excitation energy, the ON-O+ bond dissociation energy is not uniquely defined. The calculated value of non-bond-rupture is 73 - 87% in good agreement with the reported experimental value of 81%. Similar data are also presented for such molecules as CH3T, C2H5T, C3H7T, and C142H6. (author)

  7. Accounting carbon storage in decaying root systems of harvested forests.

    Science.gov (United States)

    Wang, G Geoff; Van Lear, David H; Hu, Huifeng; Kapeluck, Peter R

    2012-05-01

    Decaying root systems of harvested trees can be a significant component of belowground carbon storage, especially in intensively managed forests where harvest occurs repeatedly in relatively short rotations. Based on destructive sampling of root systems of harvested loblolly pine trees, we estimated that root systems contained about 32% (17.2 Mg ha(-1)) at the time of harvest, and about 13% (6.1 Mg ha(-1)) of the soil organic carbon 10 years later. Based on the published roundwood output data, we estimated belowground biomass at the time of harvest for loblolly-shortleaf pine forests harvested between 1995 and 2005 in South Carolina. We then calculated C that remained in the decomposing root systems in 2005 using the decay function developed for loblolly pine. Our calculations indicate that the amount of C stored in decaying roots of loblolly-shortleaf pine forests harvested between 1995 and 2005 in South Carolina was 7.1 Tg. Using a simple extrapolation method, we estimated 331.8 Tg C stored in the decomposing roots due to timber harvest from 1995 to 2005 in the conterminous USA. To fully account for the C stored in the decomposing roots of the US forests, future studies need (1) to quantify decay rates of coarse roots for major tree species in different regions, and (2) to develop a methodology that can determine C stock in decomposing roots resulting from natural mortality. PMID:22535427

  8. Accounting Carbon Storage in Decaying Root Systems of Harvested Forests

    OpenAIRE

    Wang, G. Geoff; Van Lear, David H.; Hu, Huifeng; Kapeluck, Peter R.

    2011-01-01

    Decaying root systems of harvested trees can be a significant component of belowground carbon storage, especially in intensively managed forests where harvest occurs repeatedly in relatively short rotations. Based on destructive sampling of root systems of harvested loblolly pine trees, we estimated that root systems contained about 32% (17.2 Mg ha−1) at the time of harvest, and about 13% (6.1 Mg ha−1) of the soil organic carbon 10 years later. Based on the published roundwood output data, we...

  9. New nuclear decay modes by spontaneous and beta-enhanced emission of heavy ions

    International Nuclear Information System (INIS)

    The analytical variant of the superasymmetric fussion model (ASAFM) is improved to include shell effects in the zero point vibration energy. In this way better agreement with experimental half-lives for 380 β emitters, 14C radioactivity of 222Ra and the spontaneous fission of uranium isotopes is obtained. The lifetimes of trans-lead nuclides in the range 1010-1030s are estimated for more than 150 emitted heavy ions with atomic numbers smaller than 25. The shell structure and the oddeven effects are cleary manifested in these new decay modes. One way to enhance the emission rates for these processes is to use α-decaying precursors populating excited levels from which quantum mechanical tunneling goes faster. (authors)

  10. Calculations on decay rates of various proton emissions

    Energy Technology Data Exchange (ETDEWEB)

    Qian, Yibin [Nanjing University of Science and Technology, Department of Applied Physics, Nanjing (China); Nanjing University, Department of Physics and Key Laboratory of Modern Acoustics, Nanjing (China); Ren, Zhongzhou [Nanjing University, Department of Physics and Key Laboratory of Modern Acoustics, Nanjing (China); Kavli Institute for Theoretical Physics China, Beijing (China); National Laboratory of Heavy-Ion Accelerator, Center of Theoretical Nuclear Physics, Lanzou (China)

    2016-03-15

    Proton radioactivity of neutron-deficient nuclei around the dripline has been systematically studied within the deformed density-dependent model. The crucial proton-nucleus potential is constructed via the single-folding integral of the density distribution of daughter nuclei and the effective M3Y nucleon-nucleon interaction or the proton-proton Coulomb interaction. After the decay width is obtained by the modified two-potential approach, the final decay half-lives can be achieved by involving the spectroscopic factors from the relativistic mean-field (RMF) theory combined with the BCS method. Moreover, a simple formula along with only one adjusted parameter is tentatively proposed to evaluate the half-lives of proton emitters, where the introduction of nuclear deformation is somewhat discussed as well. It is found that the calculated results are in satisfactory agreement with the experimental values and consistent with other theoretical studies, indicating that the present approach can be applied to the case of proton emission. Predictions on half-lives are made for possible proton emitters, which may be useful for future experiments. (orig.)

  11. Ways for carbon low emission in Brazil

    International Nuclear Information System (INIS)

    This report focused the challenge presented for contribution of the reduction process of carbon emission. This document identifies the reduction of deforesting and the emission from the cattle rising and agricultural activities as the main reduction opportunities, representing 85 % of the country potential

  12. Systems accounting for energy consumption and carbon emission by building

    Science.gov (United States)

    Shao, Ling; Chen, G. Q.; Chen, Z. M.; Guo, Shan; Han, M. Y.; Zhang, Bo; Hayat, T.; Alsaedi, A.; Ahmad, B.

    2014-06-01

    The method of systems accounting for overall energy consumption and carbon emission induced by a building is illustrated in terms of a combination of process and input-output analyses with a concrete procedure to cover various material, equipment, energy and manpower inputs. A detailed case study based on raw project data in the Bill of Quantities (BOQ) is performed for the structure engineering of the landmark buildings in E-town, Beijing (Beijing Economic-Technological Development Area). Based on the embodied energy and carbon emission intensity database for the Chinese economy in 2007, the energy consumption and the carbon emission of the structure engineering of the case buildings are quantified as 4.15E+14 J and 4.83E+04 t CO2 Eq., corresponding to intensities of 6.91E+09 J/m2 and 0.81 t CO2 Eq./m2 floor area. Steel and concrete contribute respectively about 50% and 30% of the energy consumption and the carbon emission, as a result of the reinforced-concrete structure of the case buildings. Materials contribute up to about 90% of the total energy consumption and carbon emission, in contrast to manpower, energy and equipment around 8%, 1% and 0.1%, respectively.

  13. Synthesis of carbon-14 labeled doxylamine succinate

    International Nuclear Information System (INIS)

    Doxylamine succinate, N,N-dimethyl-2-[1-phenyl-1-(2-pyridinyl)-ethoxy]ethanamine succinate is an antihistamine used primarily as a sedative. Carbon-14 labeled doxylamine succinate, required for toxicological studies, was synthesized in two steps starting from 2-benzoyl pyridine. (author)

  14. The management of carbon-14 in Canadian nuclear facilities

    International Nuclear Information System (INIS)

    In Canada, Derived Emission Limits (DELs) for the release of radionuclides from nuclear facilities are set to ensure that the dose to a member of a critical group from one year's release does not exceed the limit on annual dose to a member of the public set by the Atomic Energy Control Regulations. The Advisory Committee on Radiological Protection (ACRP) has expressed concerns as to whether this procedure provides adequate protection to members of the public, including future generations, for certain radionuclides such as a carbon-14 (14C), which can accumulate in the environment and which can be dispersed, through environmental processes, beyond the local region where the critical group is assumed to live. The ACRP subsequently established a Working Group to review the production, release, environmental levels, and waste management of 14C arising in CANDU power reactors. The ACRP recommendations resulting from this review can be summarized as · Given the current levels of emissions from CANDU nuclear power stations resulting from the use of a carbon dioxide annulus gas and the limitations in the calculation and use of collective dose, the ACRP sees no need for and additional collective dose limit to be applied to these sources. · The AECB should require licensees of power reactors and waste management sites to provide an annual inventory of 14C held within reactor buildings and waste management sites; to provide information on the stability of the ion exchange resins and their continuing ability to retain the 14C; to demonstrate on an ongoing basis that releases of 14C are maintained at a small fraction of the emission limits; and to report annually the critical group and local collective doses arising from releases of 14C. 61 refs., 25 tabs., 4 figs

  15. Light Emission in Silicon from Carbon Nanotubes

    CERN Document Server

    Gaufrès, Etienne; Noury, Adrien; Roux, Xavier Le; Rasigade, Gilles; Beck, Alexandre; Vivien, Laurent

    2015-01-01

    The use of optics in microelectronic circuits to overcome the limitation of metallic interconnects is more and more considered as a viable solution. Among future silicon compatible materials, carbon nanotubes are promising candidates thanks to their ability to emit, modulate and detect light in the wavelength range of silicon transparency. We report the first integration of carbon nanotubes with silicon waveguides, successfully coupling their emission and absorption properties. A complete study of this coupling between carbon nanotubes and silicon waveguides was carried out, which led to the demonstration of the temperature-independent emission from carbon nanotubes in silicon at a wavelength of 1.3 {\\mu}m. This represents the first milestone in the development of photonics based on carbon nanotubes on silicon.

  16. X-raying Extended emission and rapid decay of short gamma-ray bursts

    CERN Document Server

    Kagawa, Yasuaki; Sawano, Tatsuya; Toyanago, Asuka; Nakamura, Takashi; Takahashi, Keitaro; Kashiyama, Kazumi; Ioka, Kunihito

    2015-01-01

    Extended emission is a mystery in short gamma-ray bursts (SGRBs). By making time resolved spectral analyses of brightest eight events observed by {\\it Swift} XRT, we obviously classify the early X-ray emission of SGRBs into two types. One is the extended emission with exponentially rapid decay, which shows significant spectral softening during hundreds seconds since the SGRB trigger and is also detected by {\\it Swift}-BAT. The other is a dim afterglow only showing power-law decay over $10^4$ s. The correlations between the temporal decay and spectral indices of the extended emissions are inconsistent with the $\\alpha$-$\\beta$ correlation expected for the high-latitude curvature emission from a uniform jet. The observed too-rapid decay suggests the emission from a photosphere or a patchy surface, and manifests the stopping central engine via such as magnetic reconnection at the black hole.

  17. Direct pion emission in D*+ → D+π decays

    Science.gov (United States)

    Guo, Xing-Dao; Liu, Xue-Wen; Ke, Hong-Wei; Li, Xue-Qian

    2016-07-01

    The QCD multipole expansion (QCDME) is based on quantum field theory and has been extensively applied to study transitions among ϒ and ψ family members. As it refers to non-perturbative QCD, however, it has only a certain application range. Even though it successfully explains the transition data among members of the ϒ (ψ) family, as Eichten indicates, beyond the production threshold of mediate states it fails to match data by several orders of magnitude. In this work, by studying a simple decay mode D*→ D + π0, where a pion may be emitted before D* transitions into D, we analyze the contribution of QCD multipole expansion. As the Dπ portal is open, the dominant contribution is an OZI-allowed process where a light quark-pair is excited out from vacuum, and its contribution can be evaluated by the 3 P 0 model. Since direct pion emission is OZI-suppressed and violates isospin conservation, its contribution must be much smaller than the dominant one. By a careful calculation, we estimate that the QCDME contribution should be 3–4 orders smaller than the dominant contribution and this result can offer a quantitative interpretation for Eichten's statement. Supported by National Natural Science Foundation of China (11375128)

  18. Carbon emission from global hydroelectric reservoirs revisited.

    Science.gov (United States)

    Li, Siyue; Zhang, Quanfa

    2014-12-01

    Substantial greenhouse gas (GHG) emissions from hydropower reservoirs have been of great concerns recently, yet the significant carbon emitters of drawdown area and reservoir downstream (including spillways and turbines as well as river reaches below dams) have not been included in global carbon budget. Here, we revisit GHG emission from hydropower reservoirs by considering reservoir surface area, drawdown zone and reservoir downstream. Our estimates demonstrate around 301.3 Tg carbon dioxide (CO2)/year and 18.7 Tg methane (CH4)/year from global hydroelectric reservoirs, which are much higher than recent observations. The sum of drawdown and downstream emission, which is generally overlooked, represents 42 % CO2 and 67 % CH4 of the total emissions from hydropower reservoirs. Accordingly, the global average emissions from hydropower are estimated to be 92 g CO2/kWh and 5.7 g CH4/kWh. Nonetheless, global hydroelectricity could currently reduce approximate 2,351 Tg CO2eq/year with respect to fuel fossil plant alternative. The new findings show a substantial revision of carbon emission from the global hydropower reservoirs. PMID:24943886

  19. Trading permanent and temporary carbon emissions credits

    Energy Technology Data Exchange (ETDEWEB)

    Marland, Gregg [ORNL; Marland, Eric [Appalachian State University

    2009-08-01

    In this issue of Climatic Change, Van Kooten (2009) addresses an issue that has bedeviled negotiators since the drafting stage of the Kyoto Protocol. If we accept that increasing withdrawals of carbon dioxide from the atmpshere has the same net impact on the climate system as reducing emissions of carbon dioxide to the atmosphere, how do we design a system that allows trading of one for the other? As van Kooten expresses the challenge: 'The problem is that emissions reduction and carbon sequestration, while opposite sides of the same coin in some sense, are not directly comparable, thereby inhibiting their trade in carbon markets.' He explains: 'The difficulty centers on the length of time that mitigation strategies without CO{sub 2} from entering the atmosphere - the duration problem.' While reducing emissions of CO{sub 2} represents an essentially permanent benefit for the atmosphere, capturing CO{sub 2} that has been produced (whether capture is from the atmosphere or directly from, for example, the exhaust from power plants) there is the challenge of storing the carbon adn the risk that it will yet escape to the atmosphere. Permanent benefit to the atmosphere is often not assured for carbon sequestration activities. This is especially true if the carbon is taken up and stored in the biosphere - e.g. in forest trees or agricultural soils.

  20. Carbon footprint and ammonia emissions of California beef production systems.

    Science.gov (United States)

    Stackhouse-Lawson, K R; Rotz, C A; Oltjen, J W; Mitloehner, F M

    2012-12-01

    Beef production is a recognized source of greenhouse gas (GHG) and ammonia (NH(3)) emissions; however, little information exists on the net emissions from beef production systems. A partial life cycle assessment (LCA) was conducted using the Integrated Farm System Model (IFSM) to estimate GHG and NH(3) emissions from representative beef production systems in California. The IFSM is a process-level farm model that simulates crop growth, feed production and use, animal growth, and the return of manure nutrients back to the land to predict the environmental impacts and economics of production systems. Ammonia emissions are determined by summing the emissions from animal housing facilities, manure storage, field applied manure, and direct deposits of manure on pasture and rangeland. All important sources and sinks of methane, nitrous oxide, and carbon dioxide are predicted from primary and secondary emission sources. Primary sources include enteric fermentation, manure, cropland used in feed production, and fuel combustion. Secondary emissions occur during the production of resources used on the farm, which include fuel, electricity, machinery, fertilizer, and purchased animals. The carbon footprint is the net exchange of all GHG in carbon dioxide equivalent (CO(2)e) units per kg of HCW produced. Simulated beef production systems included cow-calf, stocker, and feedlot phases for the traditional British beef breeds and calf ranch and feedlot phases for Holstein steers. An evaluation of differing production management strategies resulted in ammonia emissions ranging from 98 ± 13 to 141 ± 27 g/kg HCW and carbon footprints of 10.7 ± 1.4 to 22.6 ± 2.0 kg CO(2)e/kg HCW. Within the British beef production cycle, the cow-calf phase was responsible for 69 to 72% of total GHG emissions with 17 to 27% from feedlot sources. Holstein steers that entered the beef production system as a by-product of dairy production had the lowest carbon footprint because the emissions

  1. CIVIL AVIATION CARBON DIOXIDE EMISSIONS IN CHINA

    OpenAIRE

    Chen, Sainan

    2013-01-01

    With the social and economic development, the civil aviation industry of China is experiencing rapid growth. This growth will lead to more CO2 emissions. Carbon dioxide emissions and greenhouse effect are already serious problems especially in China, but also all over the world. Civil aviation has brought environmental pollution in the context of improving social activity and economic growth. Because of civil aviation, the rapid increase of the total amount of air pollutants are also in...

  2. The Megacities Carbon Project: measuring urban carbon emissions

    Science.gov (United States)

    Duren, R. M.; Kort, E. A.; Miller, C. E.

    2012-12-01

    Carbon emissions from cities represent the single largest human contribution to climate change. Robust verification of emission changes due to growth or stabilization policies requires that we establish measurement baselines today and begin monitoring representative megacities immediately. An observing system designed to monitor the localized enhancements ("urban domes") of carbon dioxide and methane associated with cities must include a tiered set of surface, airborne, and satellite sensors and a framework for integrating top-down (atmospheric) and bottom-up (activity) data. We present a vision, strategy, requirements, and roadmap for an international effort to assess directly the carbon emission trends of the world's megacities. We describe a new coordinated pilot project for the megacities of Los Angeles and Paris that leverages and extends established measurement infrastructure in those cities and techniques being developed in methodological studies of smaller cities.

  3. Agricultural influences on carbon emissions and sequestration

    OpenAIRE

    Ball, Andrew S.; Pretty, Jules N.

    2002-01-01

    This report was presented at the UK Organic Research 2002 Conference. Agricultural systems contribute to carbon emissions through several mechanisms: the direct use of fossil fuels in farm operations, the indirect use of embodied energy in inputs that are energy intensive to manufacture (e.g. fertilizers), and the cultivation of soils resulting in the loss of soil organic matter. However agriculture can also sequester carbon when organic matter accumulates in the soil or above-ground woody bi...

  4. Does politics impact carbon emissions?

    OpenAIRE

    Fuchs, Doris; Detlef F. Sprinz; Aklin, Michael; Meyer-Eppler, Richard

    2009-01-01

    "Do political variables influence long-term environmental transitions? The discussion on the determinants of the environmental performance of countries has been dominated by a focus on the Environmental Kuznets curve. This concept concentrated primarily on the role of economic factors, in particular per capita income levels. By contrast, we outline both conceptually and empirically how political factors can affect long-term carbon trajectories. Our findings from an error-correction model sugg...

  5. Concentration of carbon-14 in plants

    International Nuclear Information System (INIS)

    The carbon-14 survey program initiated 1960 to gather data on current levels of carbon-14 in environments. Plants essential oil and fermented alcohol were selected as sample materials. The carbon contained in these materials is fixed from atmospheric carbon dioxide by anabolism, so they well reflect the variation of carbon-14 in biosphere. Thymol; Thymol was obtained from the essential oil of Orthodon Japonicium Benth which was cultivated and harvested every year in the experimental field of NIRS and Chiba University. The methylation was carried out to eliminate the strong quenching action of the phenolic group of thymol. Eighteen grams of thymol methyl ether was used as liquid scintillator by adding 0.4% PPO and 0.01% POPOP. Menthol; Menthol was obtained from Mentha arvensis L which was cultivated in the east part of Hokkaido and prepared by Kitami Factory of Federation of Agricultural Cooperative Society of Hokkaido. The chemical conversion of menthol to p-cymene was carried out and used as liquid scintillator as same as above sample. Lemongrass oil; Lemongrass oil was obtained from Cymbopogon citratus Stapf which was cultivated in Izu Experimental Station of Medicinal Plants, National Institute of Hygienic Science located Minami-Izu, Shizuoka Pref. The p-cymene derived from Lemongrass oil was used as liquid scintillator. Alcohol; All sample of fermented alcohol were obtained from the Alcohol Factories of Ministry of Trade and Industry. Raw materials of alcohol were sweet potatos cultivated in several prefectures in Japan ''high test'' molasses and blackstrap molasses imported from several countries of Asia, South America and South Africa, crude alcohol imported from U.S.A., Argentina and Brazil. Mixed solvent of 10 ml sample alcohol and 10 ml toluene or p-xylene containing 0.8% PPO and 0.1% dimethyl POPOP was used as liquid scintillator. (author)

  6. The lichens, tritium and carbon 14 integrators

    International Nuclear Information System (INIS)

    The present report concerns a research for the tritium and for the carbon 14 in lichens in a spirit of bio-indication: the first results appear in Daillant and al (2004 ) and additional results were presented to the congress B.I.O.M.A.P. in Slovenia, organized collectively by the institute Josef Stefan from Ljubljana and the international atomic energy agency from Vienna (Daillant and al 2003). (N.C.)

  7. Precise measurement of prompt photon emission for carbon ion therapy

    CERN Document Server

    Agodi, C; Cirrone, G A P; Collamati, F; Cuttone, G; De Lucia, E; De Napoli, M; Di Domenico, A; Faccini, R; Ferroni, F; Fiore, S; Gauzzi, P; Iarocci, E; Marafini, M; Mattei, I; Paoloni, A; Patera, V; Piersanti, L; Romano, F; Sarti, A; Sciubba, A; Voena, C

    2011-01-01

    Proton and carbon ion therapy is an emerging technique used for the treatment of solid cancers. The monitoring of the dose delivered during such treatments is still a matter of research. A possible technique exploits the information provided by single photon emission from nuclear decays induced by the irradiation. This paper reports the measurements of the spectrum and rate of such photons produced from the interaction of a 80 MeV/u fully stripped carbon ion beam at the Laboratori Nazionali del Sud of INFN, Catania, with a Poly-methyl methacrylate target. The differential production rate for photons with energy E > 2 MeV and emitted at 90 degree is found to be $dN_{\\gamma}/(dN_C d\\Omega)=(2.92\\pm 0.19)\\times 10^{-2}$sr$^{-1}$.

  8. Variations in carbon emissions from vehicles at signalised intersections

    OpenAIRE

    Ing, Koh

    2011-01-01

    Carbon emissions from road transport make up 20% of the total greenhouse gas emissions in the UK. Therefore, reducing carbon emissions from road transport is significant in reaching carbon reduction targets. In urban areas where signal controlled intersections are common, carbon emissions from vehicular traffic can be aggravated by aggressive driving and interruptions induced by traffic control. Considerable variations in speed and acceleration profiles could be observed between high carbon a...

  9. Production and decay of Δ'S in nuclei; emission of coherent pions in charge exchange

    International Nuclear Information System (INIS)

    The decay channels of the Δ resonance formed in nuclei, by the charge exchange reaction (3He,t) at 2 GeV, have been studied, on 2H, 4He, 12C and Pb targets, in exclusive experiments with the large acceptance detector Diogene. The quasi-free channel Δ++ -> p+ π+, the two proton decay channel and the single pion decay channel have been observed and investigated. The emission of coherent pions has been identified. (authors). 8 refs., 11 figs

  10. Tourism Transport, Technology, and Carbon Dioxide Emissions

    NARCIS (Netherlands)

    Peeters, P.M.

    2010-01-01

    Technological development from horse-drawn carriages to the new Airbus A380 has led to a remarkable increase in both the capacity and speed of tourist travel. This development has an endogenous systemic cause and will continue to increase carbon dioxide emissions/energy consumption if left unchecked

  11. Carbon Emissions from air-Conditioning

    Directory of Open Access Journals (Sweden)

    Rajesh Kumar

    2013-01-01

    Full Text Available This paper explores electricity consumption and carbon emissions associated with air-conditioning. The total heat load of a room fitted with air conditioner of 1.5 ton capacity has been calculated by calculating conduction and ventilation losses. Solar heat gain and internal gain were taken as the other two parameters for the total heat calculation.

  12. TOWARDS CARBON EMISSION REDUCTION USING ICT

    Directory of Open Access Journals (Sweden)

    Tiroyamodimo Mogotlhwane

    2014-06-01

    Full Text Available The impact of global warming is now showing its ability to disturb human and other forms of life on the earth. Environmental pollution and how it can be minimised is a global issue for discussion. There is an increase in promoting human activities that are environmental friendly through the “green” initiatives. Green computing is how the computing profession is responding to concern for minimising environmental pollution. Internet based operations enable work to be done remotely minimising the need for human movement. Automation of processes, one of the benefits of computing minimise waste and indirectly reduce the need for human involvement. Fossil fuels used as fuel for vehicles are some of the leading causes of carbon emission. The ability for people to work from home (telecommuting, access banking services online (online banking and other online based operations have the potential to reduce carbon emissions. These online operations are computer driven and enable professional expertise/service to be accessed without the need for people to travel. Computing applications have the potential to reduce or minimise carbon emission. More concerted effort is required from policy makers to embrace computing technologies as tools to reduce carbon emissions.

  13. LDEO Carbon 14 Data from Selected Sea floor Cores

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Carbon-14 data in this file were compiled by W.F. Ruddiman and staff at the Lamont-Doherty Earth Observatory of Columbia University. Data include 974 carbon-14...

  14. A gaseous measurement system for carbon-14 dioxide and carbon-14 methane: An analytical methodology to be applied in the evaluation of the carbon-14 dioxide and carbon-14 methane produced via microbial activity in volcanic tuff

    International Nuclear Information System (INIS)

    The objectives of this study were to develop a gaseous measurement system for the carbon-14 dioxide and carbon-14 methane produced via microbial activity or geochemical action on leachate in tuff; to determine the trapping efficiency of the system for carbon-14 dioxide; to determine the trapping efficiency of the system for carbon-14 methane; to apply the experimentally determined factors regarding the system's trapping efficiency for carbon-14 dioxide and carbon-14 methane to a trapping algorithm to determine the activity of the carbon-14 dioxide and carbon-14 methane in a mixed sample; to determine the minimum detectable activity of the measurement process in picocuries per liter; and to determine the lower limit or detection of the measurement process in counts per minute

  15. Black Carbon Emissions from Associated Natural Gas Flaring.

    Science.gov (United States)

    Weyant, Cheryl L; Shepson, Paul B; Subramanian, R; Cambaliza, Maria O L; Heimburger, Alexie; McCabe, David; Baum, Ellen; Stirm, Brian H; Bond, Tami C

    2016-02-16

    Approximately 150 billion cubic meters (BCM) of natural gas is flared and vented in the world annually, emitting greenhouse gases and other pollutants with no energy benefit. About 7 BCM per year is flared in the United States, and half is from North Dakota alone. There are few emission measurements from associated gas flares and limited black carbon (BC) emission factors have been previously reported from the field. Emission plumes from 26 individual flares in the Bakken formation in North Dakota were sampled. Methane, carbon dioxide, and BC were measured simultaneously, allowing the calculation of BC mass emission factors using the carbon balance method. Particle optical absorption was measured using a three-wavelength particle soot absorption photometer (PSAP) and BC particle number and mass concentrations were measured with a single particle soot photometer. The BC emission factors varied over 2 orders of magnitude, with an average and uncertainty range of 0.14 ± 0.12 g/kg hydrocarbons in associated gas and a median of 0.07 g/kg which represents a lower bound on these measurements. An estimation of the BC emission factor derived from PSAP absorption provides an upper bound at 3.1 g/kg. These results are lower than previous estimations and laboratory measurements. The BC mass absorption cross section was 16 ± 12 m(2)/g BC at 530 nm. The average absorption Ångström exponent was 1.2 ± 0.8, suggesting that most of the light absorbing aerosol measured was black carbon and the contribution of light absorbing organic carbon was small. PMID:26764563

  16. Estimating carbon emissions from African wildfires

    Directory of Open Access Journals (Sweden)

    V. Lehsten

    2008-08-01

    Full Text Available Africa is a continent dominated by fire. Vegetation fires, occurring naturally or human-ignited as a land management practice, have a long history in the continent's savannah ecosystems. These fires contribute substantially to the total carbon emissions (e.g. as CO2, CO, CH4, Volatile Organic Compounds, Black Carbon over large parts of the continent.

    Many recent attempts to assess the total area burnt and the amount of carbon emitted have been based on satellite remote sensing of active fires. To calculate emissions, the burned area estimates are typically multiplied with emission factors that are specific for each compound and land cover type, or used to distribute output from a biogeochemical model spatially. We developed a technique for estimating carbon emissions using a modelling approach to scale burned area estimates from L3JRC, a map recently generated from remote sensing of burn scars instead of active fires. Carbon fluxes were calculated by the novel fire model SPITFIRE embedded within the dynamic vegetation model framework LPJ-GUESS, using daily climate input.

    For the time period from 2001 to 2005 an average area of 195.5±24×104 km2 was burned annually, releasing an average of 723±70 Tg C to the atmosphere; these estimates for the biomass burned are within the range of previously published estimates. Despite the fact that the majority of wildfires are ignited by humans, strong relationships with climatic conditions have been identified in savannas worldwide, driving inter-annual variability. Our investigation of the relationships amongst carbon emissions and its potential drivers, available litter and precipitation showed that burned area as well as carbon emissions show a uni-modal response to precipitation with a maximum at ca. 1000 mm annual precipitation for burned area and emissions and a maximum of ca. 1200 mm annual precipitation for litter availability.

  17. Carbon-14 measurement using carbon dioxide absorption method - Our experience

    International Nuclear Information System (INIS)

    Carbon-C14 measurement using absorption technique consists of direct absorption of sample carbon dioxide into an absorber - scintillator mixture. This technique is a simple, fast, less expensive and less hazardous technique compared to benzene synthesis or any other technique. This techniques enable us in preparing six/seven samples in a day while benzene synthesis technique takes two days for the preparation of one sample. It is useful for radiocarbon age up to about 38,000 a BP (∼1 pMC), which is adequate for most of the hydrological investigations. All the total dissolved inorganic carbon (TDIC) is precipitated as barium carbonate from the ∼60 to 70 liters of water at the site. In the laboratory, it is reacted with orthophosphoric acid to give carbon dioxide (CO2). This carbon dioxide is transferred into 0.5 L capacity cylinder. The reaction and collection of gas is done under vacuum using a glass vacuum line. Carbon dioxide is directly absorbed in 11.5 ml of carbasorb + 11 ml of Permaflour V (commercially not available) or its equivalent scintillator in the specially made absorption apparatus. Since, absorption process is exothermic, temperature of the medium is maintained at about 220 deg. C, it results in the absorption of ∼7 m moles of carbon dioxide per mL of cabasorb. As reaction progresses, bubbles can be seen rising slowly. The end point is marked by rapid rise in the solution level. Carbon dioxide obtained from oxalic acid (Standard) and background carbon dioxide are also absorbed in the same quantity of absorber and scintillator mixture. Samples, standard and background are transferred in 22 mL teflon vials and counted in low level liquid scintillation counter (LKB Wallac 1220 Quantulus) for 1000 minutes. The counting efficiency at best factor of merit (AON/ON/√B) is ∼60 % where AON is normalized net count rate of standard and B is the background count rate. The mean count rate of last fifteen background samples is 0.64 ± .0005 cpm with an

  18. Characterizing the carbon emissions of megacities

    Science.gov (United States)

    Duren, R. M.; Gurney, K. R.; Hutyra, L.; Miller, C. E.; Kort, E. A.; Rao, P.; Eldering, A.

    2014-12-01

    Anthropogenic carbon emissions from cities and their power plants represent the single largest human contribution to climate change. Many cities with large fossil-fuel CO2 and CH4 fluxes are undergoing rapid change due to development, urbanization, energy sector transformations and/or climate mitigation actions. Meanwhile, flux estimation uncertainties at these finer spatial scales remain significantly larger than those at the continental and national scales addressed by traditional carbon estimation techniques. Improved quantification and understanding of underlying processes at the urban scale will not only provide policy-relevant information and improve the understanding of urban dynamics and future scenarios, but will translate into better global-scale anthropogenic flux estimates, and advance our understanding of carbon cycle and climate feedbacks across multiple scales. An observing system including a tiered set of surface, airborne, and satellite sensors combined with process-based flux quantification from the bottom-up, can be focused spatially and sectorally to address these challenges. A thoughtfully crafted research program that is grounded in sustained, dense observations relevant to estimating urban carbon fluxes and their controlling processes and is focused on a statistically significant sample of cities will advance our understanding of the carbon cycle. We describe the Megacities Carbon Project as an example for developing and validating the integrated application of atmospheric observations from localized surface networks, aircraft campaigns, and satellites with an analytical construct for linking atmospheric information with the human activities that drive emissions.

  19. Soil metabolic transformations of carbon-14-myo-inositol, carbon-14-phytic acid and carbon-14-iron(III) phytate

    International Nuclear Information System (INIS)

    Uniformly labelled 14C-phytic acid and 14C-iron(III) phytate were synthesized from uniformly labelled 14C-myo-inositol. The three compounds were incubated in an Andosol sandy loam at 70% field capacity and 36.50C for a 12-day period. Myo-inositol, phytic acid and iron(III) phytate underwent a 61.0, 1.9 and 0% microbial oxidation respectively to CO2 during the incubation period. The rate of fixation of 14C-phytic acid was illustrated by its rapid decline in metabolism in the 12-day period. The metabolism rate of phytic was considerably reduced by the presumed formation of iron(III) and aluminium phytate. The metabolism rate of myo-inositol was reduced nine-fold after an initial rapid metabolism during the first day of incubation. The following mechanisms were observed in the soil metabolism of myo-inositol: (1) soil mineral-inositol carbon adsorption, (2) humic acid-inositol carbon adsorption, (3) the phosphorylation of myo-inositol, and (4) the epimerization of myo-inositol to chiro-inositol. The formation of (1) and (2) was found to be highly dependent upon microbial activity. Interactions (1), (2) and (3)are considered as possible mechanisms for the inhibition of the microbial oxidation of myo-inositol. The inhibition of myo-inositol oxidation via adsorption or phosphorylation is considered to be due to the chemical blockage of the stereo-specific microbial oxidative attack on the axial hydroxyl group. (author)

  20. Comprehensive decay law for emission of charged particles and exotic cluster radioactivity

    Indian Academy of Sciences (India)

    Basudeb Sahu

    2014-04-01

    A general decay formula for the emission of charged particles from metastable nuclei is developed based on the basic phenomenon of resonances occurring in quantum scattering process under Coulomb-nuclear potential. It relates the half-lives of radioactive decays with the values of the outgoing elements with masses and charges of the nuclei involved in the decay. The relation is found to be a generalization of the Geiger–Nuttall law in radioactivity and explains well all the known emissions of charged particles including clusters, alpha and proton.

  1. The Social Cost of Carbon Emissions

    OpenAIRE

    Duncan Foley; Lance Taylor

    2013-01-01

    Determining the social cost of carbon emissions (SCC) is a crucial step in the economic analysis of climate change policy as the US government’s recent decision to use a range of estimates of the SCC centered at $77/tC (or, equivalently, $21/tCO2) in cost-benefit analyses of proposed emission-control legislation underlines. This note reviews the welfare economics theory fundamental to the estimation of the SCC in both static and intertemporal contexts, examining the effects of assumptions abo...

  2. The Social Cost of Carbon Emissions

    OpenAIRE

    Duncan Foley; Lance Taylor; Armon Rezai

    2013-01-01

    Determining the social cost of carbon emissions (SCC) is a crucial step in the economic analysis of climate change policy as the US government's recent decision to use a range of estimates of the SCC centered at $77/tC (or, equivalently, $21/tCO2) in cost-benefit analyses of proposed emission-control legislation underlines. This note reviews the welfare economics theory fundamental to the estimation of the SCC in both static and intertemporal contexts, examining the effects of assumptions abo...

  3. Research on Global Carbon Emission and Sequestration

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    Prof.Fang Jingyun,member of the Chinese Academy of Science,of Peking University and colleagues published an online article on Science in July,2011 introducing the findings of an international research group about the global carbon emission and sequestration which will produce significant influence on researches on climate change as well as the international climate change policies.The research project was funded by NSFC and MOST.

  4. Earth system responses to cumulative carbon emissions

    Science.gov (United States)

    Steinacher, M.; Joos, F.

    2015-07-01

    Information on the relationship between cumulative fossil carbon emissions and multiple climate targets are essential to design emission mitigation and climate adaptation strategies. In this study, the transient responses in different climate variables are quantified for a large set of multi-forcing scenarios extended to year 2300 towards stabilization and in idealized experiments using the Bern3D-LPJ carbon-climate model. The model outcomes are constrained by 26 physical and biogeochemical observational data sets in a Bayesian, Monte-Carlo type framework. Cumulative fossil emissions of 1000 Gt C result in a global mean surface air temperature change of 1.88 °C (68 % confidence interval (c.i.): 1.28 to 2.69 °C), a decrease in surface ocean pH of 0.19 (0.18 to 0.22), and in steric sea level rise of 20 cm (13 to 27 cm until 2300). Linearity between cumulative emissions and transient response is high for pH and reasonably high for surface air and sea surface temperatures, but less pronounced for changes in Atlantic Meridional Overturning, Southern Ocean and tropical surface water saturation with respect to biogenic structures of calcium carbonate, and carbon stocks in soils. The slopes of the relationships change when CO2 is stabilized. The Transient Climate Response is constrained, primarily by long-term ocean heat observations, to 1.7 °C (68 % c.i.: 1.3 to 2.2 °C) and the Equilibrium Climate Sensitivity to 2.9 °C (2.0 to 4.2 °C). This is consistent with results by CMIP5 models, but inconsistent with recent studies that relied on short-term air temperature data affected by natural climate variability.

  5. Earth system responses to cumulative carbon emissions

    Directory of Open Access Journals (Sweden)

    M. Steinacher

    2015-07-01

    Full Text Available Information on the relationship between cumulative fossil carbon emissions and multiple climate targets are essential to design emission mitigation and climate adaptation strategies. In this study, the transient responses in different climate variables are quantified for a large set of multi-forcing scenarios extended to year 2300 towards stabilization and in idealized experiments using the Bern3D-LPJ carbon-climate model. The model outcomes are constrained by 26 physical and biogeochemical observational data sets in a Bayesian, Monte-Carlo type framework. Cumulative fossil emissions of 1000 Gt C result in a global mean surface air temperature change of 1.88 °C (68 % confidence interval (c.i.: 1.28 to 2.69 °C, a decrease in surface ocean pH of 0.19 (0.18 to 0.22, and in steric sea level rise of 20 cm (13 to 27 cm until 2300. Linearity between cumulative emissions and transient response is high for pH and reasonably high for surface air and sea surface temperatures, but less pronounced for changes in Atlantic Meridional Overturning, Southern Ocean and tropical surface water saturation with respect to biogenic structures of calcium carbonate, and carbon stocks in soils. The slopes of the relationships change when CO2 is stabilized. The Transient Climate Response is constrained, primarily by long-term ocean heat observations, to 1.7 °C (68 % c.i.: 1.3 to 2.2 °C and the Equilibrium Climate Sensitivity to 2.9 °C (2.0 to 4.2 °C. This is consistent with results by CMIP5 models, but inconsistent with recent studies that relied on short-term air temperature data affected by natural climate variability.

  6. Carbon dioxide emission from brickfields around Bangladesh

    Directory of Open Access Journals (Sweden)

    M.A. Imran

    2014-12-01

    Full Text Available The study was undertaken at six divisions of Bangladesh to investigate the CO2 emission from brickfields. to explore the rate of carbon emission over the last 10 years, based on existing technology for brick production. The finding reveals that there were more than 45,000 Brick kilns in Bangladesh which together account for about 95% of operating kilns including Bull's Trench Kiln, Fixed Chimney Kiln, Zigzag Kiln and Hoffman Kiln. These kilns were the most carbon emitting source but it varies on fuel type, kiln type and also for location. It has been found that, maximum carbon emission area was Chittagong, which was 93.150 with percentage of last 10 years and 9.310 per cent per year. Whereas Sylhet was lower carbon emission area indicating percentage 17.172 of last 10 years and 4.218 percent per year. It has been found that total annual amount of CO2 emission for 4 types brick kilns from Dhaka, Chittagong, Rajshahi, Khulana, Sylhet and Barisal were 8.862 Mt yr-1, 10.048 Mt yr-1, 12.783 Mt yr-1, 15.250 Mt yr-1, in the year of 2002, 2005, 2007 and 2010 respectively. In Mymensingh district, the maximum CO2 emission and coal consumption was obtained in Chamak brick field, which was 1882 tons and 950 tons, respectively and minimum was obtained in Zhalak brick field, which was 1039.5 tons and 525.0 tons, respectively during the year of 2013. The percentage in last 10 years of CO2 emission was 72.784 and per cent per year 7.970, which is very alarming for us. The estimates obtained from surveys and on-site investigations indicate that these kilns consume an average of 240 tons of coal to produce 1 million bricks. This type of coal has a measured calorific value of 6,400 KJ, heating value of coal is 20.93 GJ t-1 and it produces 94.61 TJ t-1 and 56.1 TJ t-1 CO2 from coal and natural gas, respectively.

  7. Trend in global black carbon emissions from 1960 to 2007.

    Science.gov (United States)

    Wang, Rong; Tao, Shu; Shen, Huizhong; Huang, Ye; Chen, Han; Balkanski, Yves; Boucher, Olivier; Ciais, Philippe; Shen, Guofeng; Li, Wei; Zhang, Yanyan; Chen, Yuanchen; Lin, Nan; Su, Shu; Li, Bengang; Liu, Junfeng; Liu, Wenxin

    2014-06-17

    Black carbon (BC) plays an important role in both climate change and health impact. Still, BC emissions as well as the historical trends are associated with high uncertainties in existing inventories. In the present study, global BC emissions from 1960 to 2007 were estimated for 64 sources, by using recompiled fuel consumption and emission factor data sets. Annual BC emissions had increased from 5.3 (3.4-8.5 as an interquartile range) to 9.1 (5.6-14.4) teragrams during this period. Our estimations are 11-16% higher than those in previous inventories. Over the period, we found that the BC emission intensity, defined as the amount of BC emitted per unit of energy production, had decreased for all the regions, especially China and India. Improvements in combustion technology and changes in fuel composition had led to an increase in energy use efficiency, and subsequently a decline of BC emission intensities in power plants, the residential sector, and transportation. On the other hand, the BC emission intensities had increased in the industrial and agricultural sectors, mainly due to an expansion of low-efficiency industry (coke and brick production) in developing countries and to an increasing usage of diesel in agriculture in developed countries. PMID:24825392

  8. Emission-energy dependence of ultrafast P-emission decay in ZnO from bulk to nanofilm

    Energy Technology Data Exchange (ETDEWEB)

    Wakaiki, Shuji, E-mail: s.wakaiki@mls.eng.osaka-u.ac.jp [Department of Material and Life Science, Division of Advanced Science and Biotechnology, Graduate School of Engineering, Osaka University, 2-1 Yamada-oka, Suita, Osaka 565-0871 (Japan); Ichida, Hideki [Department of Material and Life Science, Division of Advanced Science and Biotechnology, Graduate School of Engineering, Osaka University, 2-1 Yamada-oka, Suita, Osaka 565-0871 (Japan); Science and Technology Entrepreneurship Laboratory, Osaka University, 2-1 Yamada-oka, Suita, Osaka 565-0871 (Japan); Bamba, Motoaki [Department of Physics, Graduate School of Science, Osaka University, 1-1 Machikaneyama, Toyonaka, Osaka 560-0043 (Japan); Kawase, Toshiki; Kawakami, Masaki [Department of Applied Physics, Graduate School of Engineering, Osaka City University, 3-3-138 Sugimoto, Sumiyoshi-ku, Osaka 558-8585 (Japan); Mizoguchi, Kohji [Department of Physical Science, Graduate School of Science, Osaka Prefecture University, 1-1 Gakuen, Naka-ku, Sakai, Osaka 599-8531 (Japan); Kim, DaeGwi; Nakayama, Masaaki [Department of Applied Physics, Graduate School of Engineering, Osaka City University, 3-3-138 Sugimoto, Sumiyoshi-ku, Osaka 558-8585 (Japan); Kanematsu, Yasuo [Department of Material and Life Science, Division of Advanced Science and Biotechnology, Graduate School of Engineering, Osaka University, 2-1 Yamada-oka, Suita, Osaka 565-0871 (Japan); Science and Technology Entrepreneurship Laboratory, Osaka University, 2-1 Yamada-oka, Suita, Osaka 565-0871 (Japan)

    2014-08-01

    We have performed time-resolved photoluminescence (PL) spectroscopy for ZnO thin films with thicknesses of 90, 460, and 2800 nm under intense excitation condition. We clearly observed the P emission due to inelastic exciton–exciton scattering. It was found that, in the 460- and 2800-nm thick samples, the decay time of the P emission considerably depends on the detection energy inversely proportional to the group velocity of the polariton in a bulk crystal with each factor of proportionality. In contrast, the energy dependence is less remarkable in the 90-nm thick sample. The decay times are basically shortened with a decrease in the film thickness. The thickness dependence of the P-emission-decay profiles is explained by considering the crossover from the polariton modes in the 2800-nm thick sample (bulk-like film) to the exciton-/photon-like modes in the 90-nm thick sample (nanofilm). - Highlights: • We clearly observed the P-PL dynamics due to inelastic exciton–exciton scattering. • The P-PL decay times are basically shortened with a decrease in the film thickness. • The P-PL decay time depends on the detection energy in the bulk-like sample. • The energy dependence of the P-PL decay time almost disappears in the 90-nm sample. • The thickness dependence is explained by the crossover between exciton and photon.

  9. Emission-energy dependence of ultrafast P-emission decay in ZnO from bulk to nanofilm

    International Nuclear Information System (INIS)

    We have performed time-resolved photoluminescence (PL) spectroscopy for ZnO thin films with thicknesses of 90, 460, and 2800 nm under intense excitation condition. We clearly observed the P emission due to inelastic exciton–exciton scattering. It was found that, in the 460- and 2800-nm thick samples, the decay time of the P emission considerably depends on the detection energy inversely proportional to the group velocity of the polariton in a bulk crystal with each factor of proportionality. In contrast, the energy dependence is less remarkable in the 90-nm thick sample. The decay times are basically shortened with a decrease in the film thickness. The thickness dependence of the P-emission-decay profiles is explained by considering the crossover from the polariton modes in the 2800-nm thick sample (bulk-like film) to the exciton-/photon-like modes in the 90-nm thick sample (nanofilm). - Highlights: • We clearly observed the P-PL dynamics due to inelastic exciton–exciton scattering. • The P-PL decay times are basically shortened with a decrease in the film thickness. • The P-PL decay time depends on the detection energy in the bulk-like sample. • The energy dependence of the P-PL decay time almost disappears in the 90-nm sample. • The thickness dependence is explained by the crossover between exciton and photon

  10. Decay kinetics of the green emission in tungstates and molybdates

    Czech Academy of Sciences Publication Activity Database

    Babin, V.; Boháček, Pavel; Bender, E.; Krasnikov, A.; Mihóková, Eva; Nikl, Martin; Senguttuvan, N.; Stolovits, A.; Usuki, Y.; Zazubovich, S.

    2004-01-01

    Roč. 38, - (2004), s. 533-537. ISSN 1350-4487 R&D Projects: GA AV ČR KSK1010104 Grant ostatní: NATO SfP-Scintillators(XX) 973510 Keywords : luminescence * exciton * defects * decay kinetics * tungstates Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 0.664, year: 2004

  11. CVD growth and field emission properties of nanostructured carbon films

    International Nuclear Information System (INIS)

    An investigation of the growth mechanisms, electronical and structural properties, and field emissions of carbon films obtained by chemical vapour deposition showed that field emissions from films composed of spatially oriented carbon nanotubes and plate-like graphite nanocrystals exhibit non-metallic behaviour. The experimental evidence of work function local reduction for carbon film materials is reported here. A model of the emission site is proposed and the mechanism of field emission from nanostructured carbon materials is described. In agreement with the model proposed here, the electron emission in different carbon materials results from sp3-like defects in an sp2 network of their graphite-like component. (author)

  12. The TOPSIS Evaluation on Carbon Emission Economic Efficiency

    Institute of Scientific and Technical Information of China (English)

    Sheng; XU; Chao; ZHANG; Juan; YANG

    2013-01-01

    Based on carbon emission data of 17 cities in Shandong Province in 2005-2009,this paper analyzes carbon emission economic efficiency. It conducts weight distribution by the Ordered Weighted Averaging ( OWA) method,and takes systematic evaluation on carbon emission economic efficiency using TOPSIS method. In eastern coastal regions,including Dongying,Yantai,Weihai and Qingdao,the carbon emission economic efficiency is generally higher than inland regions of Shandong Province. The conclusion reached after correction of time weight is basically consistent with traditional TOPSIS overall evaluation,further proves validity of the evaluation. Finally,it gives recommendations for improving carbon emission economic efficiency in Shandong Province.

  13. Carbon emission patterns in different income countries

    Directory of Open Access Journals (Sweden)

    Kai Wang, Le-Le Zou, Jie Guo, Wen-Jing Yi, Zhen-Hua Feng, Yi-Ming Wei

    2011-05-01

    Full Text Available In order to find the main driving forces affecting CO2 emission patterns and the relationship between economic development and CO2 emissions, this paper uses models of Sigma-convergence, absolute Beta-convergence and conditional Beta-convergence to analyze the inner characteristics of CO2 emissions and the income level of 128 countries (and regions in the world. The countries (and regions are divided into 5 groups based on their per capita income levels. The results show that in the past 40 years, all the groups showed trends of convergence on the CO2 emissions. In terms of emission levels, lagging countries (and regions tend to catch up with advanced nations, with convergence tending to be conditional on country-specific characteristics such as energy use and energy structures rather than absolute convergence. Then this paper examines the impacts of selected variables such as GDP per capita, population, oil, gas, coal etc. on the emission trends. The analysis on the impacting factors shows that for the developing countries (and regions, the levels of economic development have greater effects on their carbon emissions patterns. And for the developed countries (and regions, the energy consumption structures wielded a big influence for the past 40 years. We find that the growth speed of CO2 emissions in developed countries (and regions would get slower, and those of the developing countries (and regions give expression to catching-up effects. These findings are expected to shed a light on the global policy making in coping climate change.

  14. Statistical analysis of time-resolved emission from ensembles of semiconductor quantum dots: Interpretation of exponential decay models

    OpenAIRE

    van Driel, A. F.; Nikolaev, I. S.; Vergeer, P.; Lodahl, Peter; Vanmaelkelbergh, D.; Vos, W.L.

    2007-01-01

    We present a statistical analysis of time-resolved spontaneous emission decay curves from ensembles of emitters, such as semiconductor quantum dots, with the aim to interpret ubiquitous non-single-exponential decay. Contrary to what is widely assumed, the density of excited emitters and the intensity in an emission decay curve are not proportional, but the density is a time-integral of the intensity. The integral relation is crucial to correctly interpret non-single-exponential decay. We deri...

  15. Laboratory Experiments to Evaluate Matrix Diffusion of Dissolved Organic Carbon Carbon-14 in Southern Nevada Fractured-rock Aquifers

    Energy Technology Data Exchange (ETDEWEB)

    Hershey, Ronald L. [Nevada University, Reno, NV (United States). Desert Research Institute; Fereday, Wyatt [Nevada University, Reno, NV (United States). Desert Research Institute

    2016-05-01

    Dissolved inorganic carbon (DIC) carbon-14 (14C) is used to estimate groundwater ages by comparing the DIC 14C content in groundwater in the recharge area to the DIC 14C content in the downgradient sampling point. However, because of chemical reactions and physical processes between groundwater and aquifer rocks, the amount of DIC 14C in groundwater can change and result in 14C loss that is not because of radioactive decay. This loss of DIC 14C results in groundwater ages that are older than the actual groundwater ages. Alternatively, dissolved organic carbon (DOC) 14C in groundwater does not react chemically with aquifer rocks, so DOC 14C ages are generally younger than DIC 14C ages. In addition to chemical reactions, 14C ages may also be altered by the physical process of matrix diffusion. The net effect of a continuous loss of 14C to the aquifer matrix by matrix diffusion and then radioactive decay is that groundwater appears to be older than it actually is. Laboratory experiments were conducted to measure matrix diffusion coefficients for DOC 14C in volcanic and carbonate aquifer rocks from southern Nevada. Experiments were conducted using bromide (Br-) as a conservative tracer and 14C-labeled trimesic acid (TMA) as a surrogate for groundwater DOC. Outcrop samples from six volcanic aquifers and five carbonate aquifers in southern Nevada were used. The average DOC 14C matrix diffusion coefficient for volcanic rocks was 2.9 x 10-7 cm2/s, whereas the average for carbonate rocks was approximately the same at 1.7 x 10-7 cm2/s. The average Br- matrix diffusion coefficient for volcanic rocks was 10.4 x 10-7 cm2/s, whereas the average for carbonate rocks was less at 6.5 x 10-7 cm2/s. Carbonate rocks exhibited greater variability in

  16. Investigations on the biokinetics of carbon 14 in algae cultures

    International Nuclear Information System (INIS)

    The uptake of 14C by Scenedesmus quadricauda is quantitatively investigated by simulation models of radio ecological relevance. Due to the complexing of the procedures in the natural ecosystem, it was only possible to consider idealized conditions. The batch culture ressembles the conditons of still waters or relatively still waters without notable water exchange. The effect of the 14C enrichment, as well as the drastic carbon reduction in the substrate as a result of algae growth, was avoided in the modified batch culture under conditions of simultaneous substrate diffusion by means of a permeation system. The 14C and 12C uptake of the cells thus took place solely under the conditions of constant concentration in the culture medium. The consequences for flowing water resulting from a nuclear power plant accident are to be simulated for the extent of the 14C uptake by green algae using the continuous culture model with dynamic 14C exposure. The continuous infusion of 14C in the continuous culture corresponds to the possible cases where 14C escapes into a flowing water at a constant rate over a long period of time, whether this may be via chronical release from a nuclear power plant or by 'fallout' resulting from nuclear arms testing. The results shown lead to the conclusion that the emission of 14C to the environment, which according to prognoses will be considerably higher after the year 2000, presents a serious radioactivity potential which man and environment will have to live with should these developments continue and the prognoses come true. (orig./MG)

  17. Searches for heavy neutrinos from 35S, 14C, and 63Ni beta decay

    International Nuclear Information System (INIS)

    We have searched for the effect of a neutrino of mass 17 keV/c2 in the beta decay of 35S with an apparatus incorporating a high resolution solid state detector and a super conducting solenoid. The experimental mixing probability of the 17keV neutrino is consistent with zero. The experimental sensitivity is verified by measurements with a mixed source of 35S and 14C, which artificially produces a distortion in the beta spectrum similar to that expected from the massive neutrino. Recently, we have performed similar searches in the beta decay of 14C and 63Ni. Results of these new measurements will be presented

  18. Neutrino emissivity from Goldstone boson decay in magnetized neutron matter

    OpenAIRE

    Bedaque, Paulo; Sen, Srimoyee

    2013-01-01

    Neutron matter at densities somewhat above nuclear densities is believed to be superfluid due to the condensation of neutron pairs in the 3 P2 channel. This condensate breaks rotational symmetry spontaneously and leads to the existence of Goldstone bosons (angulons). We show that the coupling to magnetic fields mediated by the magnetic moment of the neutron makes angulons massive and capable of decaying into a neutrino-antineutrino pair. We compute the rate for this process and argue they bec...

  19. China's regional carbon emissions change over 1997-2007

    Directory of Open Access Journals (Sweden)

    Lan-Cui Liu, Jin-Nan Wang, Gang Wu, Yi-Ming Wei

    2010-01-01

    Full Text Available The increased demand for energy in China has generated concomitant increase of carbon emissions, which poses an unprecedented challenge to China’s, and even global, sustainable development. In this paper, from the perspective of provincial carbon emissions, we analyze China’s carbon emissions changes during 1997-2007 based on the index decomposition analysis method. We find that: (1 China's CO2 emissions from end-use energy consumption mainly originated from such major industrial provinces as Hebei, Jiangsu, Zhejiang, Shandong, Henan and Guangdong. (2 Economic growth and decline in energy intensity will have the greatest impact on CO2 emissions from end-use energy consumption. Economic growth is the key factor driving the increase of CO2 emissions. Change in energy intensity can more or less decrease CO2 emissions. In the future, China’s carbon emissions mitigation policies should be developed to address these differences in provincial carbon emissions.

  20. Verification of the dispersion model by airborne carbon 14C

    International Nuclear Information System (INIS)

    This paper provides insight in the verification of the Lagrangean dispersion model for dose calculation in the environment. The verification method was based on the measurement of the airborne carbon 14C concentration which can be slightly increased close to the nuclear power plant. The results proved that this method is sensitive enough and that the sensitivity analysis can be used for model verification or for identification of possible improvements of the used meteorological data. The Lagrangean model is used at Krsko nuclear power plant (NPP) for calculation of dispersion coefficients and dose in the environment. To show compliance with the authorized dose limits it is required to present a realistic calculation of the dose to the public. This is a numerical model designed to calculate air pollution dispersion in the area of 25km x 25km. The model uses on-line local meteorological measurements. The same model was already verified for another location around a coal- fired power plant based on emission and environmental measurements of SO2. Krsko NPP is placed near the Sava River in a semiopened basin surrounded by several hills. The region is characterized by low winds and frequent thermal inversions. This paper presents a verification of the short range dispersion model based on the fact that the airborne carbon 14C concentration can be slightly increased close to the nuclear power plant. Other radioactive effluents are not detectable in the environment and carbon 14C measurements are accurate enough to detect small deviations from natural 14C levels and to compare them with the calculated concentration based on 14C effluents. The most of airborne 14C is released during the refuelling outage. Within the pre-selected period of ten days, increased effluents of 14C in the form of CO2 were sampled from the plant ventilation. The average atmospheric dispersion parameters were calculated for two locations in the environment where CO2 sampling plates were installed

  1. China's regional carbon emissions change over 1997-2007

    OpenAIRE

    Lan-Cui Liu; Jin-Nan Wang; Gang Wu; Yi-Ming Wei

    2009-01-01

    The increased demand for energy in China has generated concomitant increase of carbon emissions, which poses an unprecedented challenge to China's, and even global, sustainable development. In this paper, from the perspective of provincial carbon emissions, we analyze China's carbon emissions changes during 1997-2007 based on the index decomposition analysis method. We find that: (1) China's CO2 emissions from end-use energy consumption mainly originated from such major industrial provinces a...

  2. China's regional carbon emissions change over 1997-2007

    OpenAIRE

    Lan-Cui Liu, Jin-Nan Wang, Gang Wu, Yi-Ming Wei

    2010-01-01

    The increased demand for energy in China has generated concomitant increase of carbon emissions, which poses an unprecedented challenge to China’s, and even global, sustainable development. In this paper, from the perspective of provincial carbon emissions, we analyze China’s carbon emissions changes during 1997-2007 based on the index decomposition analysis method. We find that: (1) China's CO2 emissions from end-use energy consumption mainly originated from such major industrial provinces a...

  3. Reduced carbon emission estimates from fossil fuel combustion and cement production in China.

    Science.gov (United States)

    Liu, Zhu; Guan, Dabo; Wei, Wei; Davis, Steven J; Ciais, Philippe; Bai, Jin; Peng, Shushi; Zhang, Qiang; Hubacek, Klaus; Marland, Gregg; Andres, Robert J; Crawford-Brown, Douglas; Lin, Jintai; Zhao, Hongyan; Hong, Chaopeng; Boden, Thomas A; Feng, Kuishuang; Peters, Glen P; Xi, Fengming; Liu, Junguo; Li, Yuan; Zhao, Yu; Zeng, Ning; He, Kebin

    2015-08-20

    Nearly three-quarters of the growth in global carbon emissions from the burning of fossil fuels and cement production between 2010 and 2012 occurred in China. Yet estimates of Chinese emissions remain subject to large uncertainty; inventories of China's total fossil fuel carbon emissions in 2008 differ by 0.3 gigatonnes of carbon, or 15 per cent. The primary sources of this uncertainty are conflicting estimates of energy consumption and emission factors, the latter being uncertain because of very few actual measurements representative of the mix of Chinese fuels. Here we re-evaluate China's carbon emissions using updated and harmonized energy consumption and clinker production data and two new and comprehensive sets of measured emission factors for Chinese coal. We find that total energy consumption in China was 10 per cent higher in 2000-2012 than the value reported by China's national statistics, that emission factors for Chinese coal are on average 40 per cent lower than the default values recommended by the Intergovernmental Panel on Climate Change, and that emissions from China's cement production are 45 per cent less than recent estimates. Altogether, our revised estimate of China's CO2 emissions from fossil fuel combustion and cement production is 2.49 gigatonnes of carbon (2 standard deviations = ±7.3 per cent) in 2013, which is 14 per cent lower than the emissions reported by other prominent inventories. Over the full period 2000 to 2013, our revised estimates are 2.9 gigatonnes of carbon less than previous estimates of China's cumulative carbon emissions. Our findings suggest that overestimation of China's emissions in 2000-2013 may be larger than China's estimated total forest sink in 1990-2007 (2.66 gigatonnes of carbon) or China's land carbon sink in 2000-2009 (2.6 gigatonnes of carbon). PMID:26289204

  4. Reduced carbon emission estimates from fossil fuel combustion and cement production in China

    Science.gov (United States)

    Liu, Zhu; Guan, Dabo; Wei, Wei; Davis, Steven J.; Ciais, Philippe; Bai, Jin; Peng, Shushi; Zhang, Qiang; Hubacek, Klaus; Marland, Gregg; Andres, Robert J.; Crawford-Brown, Douglas; Lin, Jintai; Zhao, Hongyan; Hong, Chaopeng; Boden, Thomas A.; Feng, Kuishuang; Peters, Glen P.; Xi, Fengming; Liu, Junguo; Li, Yuan; Zhao, Yu; Zeng, Ning; He, Kebin

    2015-08-01

    Nearly three-quarters of the growth in global carbon emissions from the burning of fossil fuels and cement production between 2010 and 2012 occurred in China. Yet estimates of Chinese emissions remain subject to large uncertainty; inventories of China's total fossil fuel carbon emissions in 2008 differ by 0.3 gigatonnes of carbon, or 15 per cent. The primary sources of this uncertainty are conflicting estimates of energy consumption and emission factors, the latter being uncertain because of very few actual measurements representative of the mix of Chinese fuels. Here we re-evaluate China's carbon emissions using updated and harmonized energy consumption and clinker production data and two new and comprehensive sets of measured emission factors for Chinese coal. We find that total energy consumption in China was 10 per cent higher in 2000-2012 than the value reported by China's national statistics, that emission factors for Chinese coal are on average 40 per cent lower than the default values recommended by the Intergovernmental Panel on Climate Change, and that emissions from China's cement production are 45 per cent less than recent estimates. Altogether, our revised estimate of China's CO2 emissions from fossil fuel combustion and cement production is 2.49 gigatonnes of carbon (2 standard deviations = +/-7.3 per cent) in 2013, which is 14 per cent lower than the emissions reported by other prominent inventories. Over the full period 2000 to 2013, our revised estimates are 2.9 gigatonnes of carbon less than previous estimates of China's cumulative carbon emissions. Our findings suggest that overestimation of China's emissions in 2000-2013 may be larger than China's estimated total forest sink in 1990-2007 (2.66 gigatonnes of carbon) or China's land carbon sink in 2000-2009 (2.6 gigatonnes of carbon).

  5. Transient simulations of historical climate change including interactive carbon emissions from land-use change.

    Science.gov (United States)

    Matveev, A.; Matthews, H. D.

    2009-04-01

    Carbon fluxes from land conversion are among the most uncertain variables in our understanding of the contemporary carbon cycle, which limits our ability to estimate both the total human contribution to current climate forcing and the net effect of terrestrial biosphere changes on atmospheric CO2 increases. The current generation of coupled climate-carbon models have made significant progress in simulating the coupled climate and carbon cycle response to anthropogenic CO2 emissions, but do not typically include land-use change as a dynamic component of the simulation. In this work we have incorporated a book-keeping land-use carbon accounting model into the University of Victoria Earth System Climate Model (UVic ESCM), and intermediate-complexity coupled climate-carbon model. The terrestrial component of the UVic ESCM allows an aerial competition of five plant functional types (PFTs) in response to climatic conditions and area availability, and tracks the associated changes in affected carbon pools. In order to model CO2 emissions from land conversion in the terrestrial component of the model, we calculate the allocation of carbon to short and long-lived wood products following specified land-cover change, and use varying decay timescales to estimate CO2 emissions. We use recently available spatial datasets of both crop and pasture distributions to drive a series of transient simulations and estimate the net contribution of human land-use change to historical carbon emissions and climate change.

  6. Covariances between gamma-ray emission probabilities in very simple decay schemes

    International Nuclear Information System (INIS)

    The covariances between the gamma-ray emission probabilities of the two strongest electromagnetic transitions following the decays of 94Nb, 111In, 46Sc, 60Co, and 24Na were determined from their decay schemes and available data, resulting in correlation coefficients equal to 0.96, 1, 0, 0.015, and 0.04, respectively. The required assumptions and experimental and theoretical value have to be checked by the reviewers of these nuclides

  7. Measurement of Direct Photon Emission in $K^{+} \\to \\pi^{+}pi^{0} \\gamma$ Decay

    CERN Document Server

    Adler, Stephen Louis; Ardebili, M; Atiya, M S; Bergbusch, P; Blackmore, E W; Bryman, D A; Chiang, I H; Convery, M R; Diwan, M V; Frank, J S; Haggerty, J S; Inagaki, T; Ito, M M; Kabe, S; Kettell, S H; Kishi, Y; Kitching, P; Kobayashi, M; Komatsubara, T K; Konaka, A; Kuno, Y; Kuriki, M; Kycia, T F; Li Kai Kong; Littenberg, L S; MacDonald, J A; McPherson, R A; Meyers, P D; Mildenberger, J L; Muramatsu, N; Nakano, T; Numao, T; Poutissou, J M; Poutissou, R; Redlinger, G; Sato, T; Shinkawa, T; Shoemaker, F C; Soluk, R A; Stone, J R; Strand, R C; Sugimoto, S; Witzig, C; Yoshimura, Y

    2000-01-01

    We have performed a measurement of the K^+ -> pi^+ pi^0 gamma decay and have observed 2 X 10^4 events. The best fit to the decay spectrum gives a branching ratio for direct photon emission of (4.7\\pm0.8\\pm0.3) X 10^{-6} in the pi^+ kinetic energy region of 55 to 90 MeV and requires no component due to interference with inner bremsstrahlung.

  8. Measurement of direct photon emission in K+-->pi(+)pi(0)gamma decay

    Science.gov (United States)

    Adler; Aoki; Ardebili; Atiya; Bergbusch; Blackmore; Bryman; Chiang; Convery; Diwan; Frank; Haggerty; Inagaki; Ito; Kabe; Kettell; Kishi; Kitching; Kobayashi; Komatsubara; Konaka; Kuno; Kuriki; Kycia; Li; Littenberg

    2000-12-01

    We have performed a measurement of the K+-->pi(+)pi(0)gamma decay and have observed 2x10(4) events. The best fit to the decay spectrum gives a branching ratio for direct photon emission of (4.7+/-0.8+/-0. 3)x10(-6) in the pi(+) kinetic energy region of 55 to 90 MeV and requires no component due to interference with inner bremsstrahlung. PMID:11102135

  9. On leptonic decay of a heavy quarkonium with a Higgs-boson emission

    OpenAIRE

    Kozlov, G. A.

    2005-01-01

    A leptonic $(\\bar l l)$ decay of a heavy quark-antiquark bound state $T(\\bar QQ)$ with a Higgs-boson $H$ emission is investigated. The applying of the well-known low-energy theorem to meson-Higgs coupling allows one to estimate the probability of the decay $T(\\bar QQ)\\to \\bar ll H$. The only a simple version of the Standard Model extension containing two-Higgs doublet is considered.

  10. Fine structure in 14C emission from 223Ra and 224Ra

    International Nuclear Information System (INIS)

    The measurement of the energy spectrum of 14C nuclei emitted in the spontaneous radioactivity of 223Ra and 224Ra has been carried out, using thin and intense sources (480 MBq for 223Ra and 3550 MBq for 224Ra). The sources were obtained by implanting mass-separated beams into Al and vitreous C catchers. The measurement was performed with a superconducting solenoidal spectrometer. Our discovery, previously reported, of fine structure in the energy spectrum of 14C emission from 223Ra, which is analogous to the one known for α emission, is confirmed. Only 13% of the branching ratio in 14C decay leads to the ground state of the residual nucleus, while 81% to the first excited state. For 14C emission from 224Ra, a lower limit of 2 for the hindrance factor has been measured for the transition to the first excited state in the residual nucleus. Also, a precise identification in Z with an ExΔE telescope has been performed for the radiation from the 223Ra source. Our measurements of fine structure in 14C emissions open this field to nuclear structure studies

  11. Environment, Renewable Energy and Reduced Carbon Emissions

    Science.gov (United States)

    Sen, S.; Khazanov, G.; Kishimoto, Y.

    2011-01-01

    Increased energy security and reduced carbon emissions pose significant challenges for science and technology. However, they also create substantial opportunities for innovative research and development. In this review paper, we highlight some of the key opportunities and mention public policies that are needed to enable the efforts and to maximize the probability of their success. Climate is among the uttermost nonlinear behaviors found around us. As recent studies showed the possible effect of cosmic rays on the Earth's climate, we investigate how complex interactions between the planet and its environment can be responsible for climate anomalies.

  12. The learning of the evolution and temporary characteristics of the decay nuclei 14C, 238U, 232Th, 40K, 87Rb

    International Nuclear Information System (INIS)

    Quantum-mechanical method, which was proposing earlier for the theoretical description of the resonance scattering of the γ-quantum, was generalizing with Doppler effect using. New algorithm for the definition of the characteristic functions for the energy distribution, decay probability and decay functions elaborated. It gives possibility more precise estimate temporary characteristics of the nuclei chronometers and to define a number of the steps of the γ-absorption γ-emission in the decay process. It is give the quantum- mechanical ground of the necessity of revision of the temporary characteristics of the nuclei-chronometers. The calculations have been doing for the concrete case decay of exited nuclei 14C, 238U, 232Th, 40K, 87Rb under room temperature taking into account Doppler effect and without it. 4 refs., 1 tab., 6 figs

  13. The lichens, tritium and carbon 14 integrators; Les lichens, integrateurs de tritium et de carbone 14

    Energy Technology Data Exchange (ETDEWEB)

    Daillant, O

    2007-07-01

    The present report concerns a research for the tritium and for the carbon 14 in lichens in a spirit of bio-indication: the first results appear in Daillant and al (2004 ) and additional results were presented to the congress B.I.O.M.A.P. in Slovenia, organized collectively by the institute Josef Stefan from Ljubljana and the international atomic energy agency from Vienna (Daillant and al 2003). (N.C.)

  14. The role of nuclear power under carbon emission regulation

    International Nuclear Information System (INIS)

    The role of nuclear power under the carbon emission regulation was analyzed in a national economy. In order to see how much influences does the carbon emission regulation has on the national economy, scenarios on the carbon emission regulations were established. Additional scenarios on the nuclear power option (with or without) was also established to capture the role of nuclear power generation under the carbon emission regulations. The study shows that the most favorable case is, as expected, weak regulation with nuclear option, the next is strong regulation with nuclear option, followed by weak regulation without nuclear option, and the most serious case is strong regulation without nuclear option. The results from this study implies that the national economy impacts depends more on nuclear scenarios than on carbon emission regulation scenarios. The results place special emphasis on the importance of the role of nuclear power under the carbon emission regulation

  15. Behavior of carbon-14 in the Tokai reprocessing plant

    International Nuclear Information System (INIS)

    Carbon-14 released from the nuclear facilities is an important radionuclide for the safety assessment, because it tends to accumulate in environment through food chain and has a significant impact to personal dose. Carbon-14 has been monitored routinely as one of the main gaseous radionuclides exhausted from the Tokai Reprocessing Plant (TRP) since October of 1991. Furthermore, behavior of carbon-14 in TRP has been investigated through the reprocessing operation and the literature survey. This report describes the result of investigation about the behavior of carbon-14 in TRP as followings. 1. Only a very small amount of carbon-14 in the fuel was liberated into the shear off-gas and most of it was liberated into the dissolver off-gas. Part of the carbon-14 was trapped at the caustic scrubber installed in the off-gas treatment process, and untrapped carbon-14 was released into the environment from the main stack. Amount of carbon-14 released from the main stack was about 4.1∼6.5 GBq every ton of uranium reprocessed. 2. Carbon-14 trapped at the caustic scrubbers installed in the dissolver off-gas and in the vessel off-gas treatment process is transferred to the low active waste vessel. Amount of carbon-14 transferred to the low active waste vessel was about 5.4∼9.6 GBq every ton of uranium reprocessed. 3. The total amount of carbon-14 input to TRP was summed up to about 11.9∼15.5 GBq every ton of uranium reprocessed considering the released amount from the main stack and the trapped amount in the off-gas treatment devices. The amount of nitrogen impurity in the initial fuel was calculated about 15∼22ppm of uranium metal based on the measured carbon-14. 4. The solution in the low active waste vessel is concentrated at the evaporator. Most of the carbon-14 in the solution was transferred into concentrated solution. 5. Total Vitrification Demonstration Facility (TVF) started to operate in 1994. Since then, carbon-14 has been measured in the second sub stack

  16. Carbon emissions intensity ratio: an indicator for an improved carbon labelling scheme

    International Nuclear Information System (INIS)

    This letter proposes a new carbon labelling scheme to improve the visibility of products’ life cycle carbon emissions (sometimes defined as carbon footprint). This approach starts by normalizing carbon emissions data on a common scale of ‘carbon emissions intensity’, and a new indicator ‘carbon emissions intensity ratio’ is generated based upon its ratio to the annual national greenhouse gas emission per gross domestic product. Five ranges (extremely low, low, medium, high and extremely high) are used to represent the level of carbon emissions intensity ratio by a simple diagram with colour gradation. Case examples are presented, in which the carbon emissions intensity ratios of various selected products, both distinct and related, are calculated and compared. The limitations of this approach are then discussed, laying a foundation for further work. (letter)

  17. Carbon emissions from deforestation and forest fragmentation in the Brazilian Amazon

    Energy Technology Data Exchange (ETDEWEB)

    Numata, Izaya; Cochrane, Mark A [GIScCE, South Dakota State University (United States); Souza, Carlos M Jr; Sales, Marcio H [Instituto do Homen e Meio Ambiente da Amazonia-IMAZON (Brazil)

    2011-10-15

    Forest-fragmentation-related edge effects are one of the major causes of forest degradation in Amazonia and their spatio-temporal dynamics are highly influenced by annual deforestation patterns. Rapid biomass collapse due to edge effects in forest fragments has been reported in the Brazilian Amazon; however the collective impacts of this process on Amazonian carbon fluxes are poorly understood. We estimated biomass loss and carbon emissions from deforestation and forest fragmentation related to edge effects on the basis of the INPE (Brazilian National Space Research Institute) PRODES deforestation data and forest biomass volume data. The areas and ages of edge forests were calculated annually and the corresponding biomass loss and carbon emissions from these forest edges were estimated using published rates of biomass decay and decomposition corresponding to the areas and ages of edge forests. Our analysis estimated carbon fluxes from deforestation (4195 Tg C) and edge forest (126-221 Tg C) for 2001-10 in the Brazilian Amazon. The impacts of varying rates of deforestation on regional forest fragmentation and carbon fluxes were also investigated, with the focus on two periods: 2001-5 (high deforestation rates) and 2006-10 (low deforestation rates). Edge-released carbon accounted for 2.6-4.5% of deforestation-related carbon emissions. However, the relative importance of carbon emissions from forest fragmentation increased from 1.7-3.0% to 3.3-5.6% of the respective deforestation emissions between the two contrasting deforestation rates. Edge-related carbon fluxes are of increasing importance for basin-wide carbon accounting, especially as regards ongoing reducing emissions from deforestation and forest degradation (REDD) efforts in Brazilian Amazonia.

  18. Carbon emissions from deforestation and forest fragmentation in the Brazilian Amazon

    International Nuclear Information System (INIS)

    Forest-fragmentation-related edge effects are one of the major causes of forest degradation in Amazonia and their spatio-temporal dynamics are highly influenced by annual deforestation patterns. Rapid biomass collapse due to edge effects in forest fragments has been reported in the Brazilian Amazon; however the collective impacts of this process on Amazonian carbon fluxes are poorly understood. We estimated biomass loss and carbon emissions from deforestation and forest fragmentation related to edge effects on the basis of the INPE (Brazilian National Space Research Institute) PRODES deforestation data and forest biomass volume data. The areas and ages of edge forests were calculated annually and the corresponding biomass loss and carbon emissions from these forest edges were estimated using published rates of biomass decay and decomposition corresponding to the areas and ages of edge forests. Our analysis estimated carbon fluxes from deforestation (4195 Tg C) and edge forest (126-221 Tg C) for 2001-10 in the Brazilian Amazon. The impacts of varying rates of deforestation on regional forest fragmentation and carbon fluxes were also investigated, with the focus on two periods: 2001-5 (high deforestation rates) and 2006-10 (low deforestation rates). Edge-released carbon accounted for 2.6-4.5% of deforestation-related carbon emissions. However, the relative importance of carbon emissions from forest fragmentation increased from 1.7-3.0% to 3.3-5.6% of the respective deforestation emissions between the two contrasting deforestation rates. Edge-related carbon fluxes are of increasing importance for basin-wide carbon accounting, especially as regards ongoing reducing emissions from deforestation and forest degradation (REDD) efforts in Brazilian Amazonia.

  19. Effect of Population Structure Change on Carbon Emission in China

    OpenAIRE

    Wen Guo; Tao Sun; Hongjun Dai

    2016-01-01

    This paper expanded the Logarithmic Mean Divisia Index (LMDI) model through the introduction of urbanization, residents’ consumption, and other factors, and decomposed carbon emission changes in China into carbon emission factor effect, energy intensity effect, consumption inhibitory factor effect, urbanization effect, residents’ consumption effect, and population scale effect, and then explored contribution rates and action mechanisms of the above six factors on change in carbon emissions in...

  20. Carbon dioxide emission from bamboo culms.

    Science.gov (United States)

    Zachariah, E J; Sabulal, B; Nair, D N K; Johnson, A J; Kumar, C S P

    2016-05-01

    Bamboos are one of the fastest growing plants on Earth, and are widely considered to have high ability to capture and sequester atmospheric carbon, and consequently to mitigate climate change. We tested this hypothesis by measuring carbon dioxide (CO2 ) emissions from bamboo culms and comparing them with their biomass sequestration potential. We analysed diurnal effluxes from Bambusa vulgaris culm surface and gas mixtures inside hollow sections of various bamboos using gas chromatography. Corresponding variations in gas pressure inside the bamboo section and culm surface temperature were measured. SEM micrographs of rhizome and bud portions of bamboo culms were also recorded. We found very high CO2 effluxes from culm surface, nodes and buds of bamboos. Positive gas pressure and very high concentrations of CO2 were observed inside hollow sections of bamboos. The CO2 effluxes observed from bamboos were very high compared to their carbon sequestration potential. Our measurements suggest that bamboos are net emitters of CO2 during their lifespan. PMID:26802362

  1. Kenya Airways Launches New Project to Reduce Carbon Emissions

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    Kenya Airways announced its new carbon offset project in May,aiming to have guests directly take part in a carbon emissions reduction plan for environmental protection.Titus Naikuni,Managing Director of

  2. Statistical analysis of time-resolved emission from ensembles of semiconductor quantum dots: Interpretation of exponential decay models

    DEFF Research Database (Denmark)

    Van Driel, A.F.; Nikolaev, I.S.; Vergeer, P.; Lodahl, Peter; Vanmaelkelbergh, D.; Vos, W.L.

    2007-01-01

    We present a statistical analysis of time-resolved spontaneous emission decay curves from ensembles of emitters, such as semiconductor quantum dots, with the aim of interpreting ubiquitous non-single-exponential decay. Contrary to what is widely assumed, the density of excited emitters and the...... intensity in an emission decay curve are not proportional, but the density is a time integral of the intensity. The integral relation is crucial to correctly interpret non-single-exponential decay. We derive the proper normalization for both a discrete and a continuous distribution of rates, where every...... single number, but is also distributed. We derive a practical description of non-single-exponential emission decay curves in terms of a single distribution of decay rates; the resulting distribution is identified as the distribution of total decay rates weighted with the radiative rates. We apply our...

  3. On the possible mixing of the electron capture and the positron emission channels in nuclear decay

    OpenAIRE

    Isakov, V. I.

    2009-01-01

    On the basis of the idea of mixing (interaction) between the electron capture and the positron emission channels in the \\beta^+ decay in the cases when both channels are energetically allowed, we attempt to explain oscillations of the K-capture rates that were possibly seen in the recent experiment.

  4. (Super)rare decays of an extra Z' boson via Higgs boson emission

    OpenAIRE

    Kozlov, G. A.

    1999-01-01

    The phenomenological model of an extra U(1) neutral gauge Z' boson coupled to heavy quarks is presented. In particular, we discuss the probability for a light $Z_{2}$ mass eigenstate decay into a bound state composed of heavy quarks via Higgs boson emission.

  5. The optimization of the estimation of carbon-14 in urine

    International Nuclear Information System (INIS)

    The urinalysis method for carbon-14 currently used by the bioassay laboratory of the Dosimetric Research Branch at CRNL has been tested and optimized for both sensitivity and efficiency. Urine is first treated with an enzyme that catalyses the hydrolysis of urea, the major carbon-containing component of urine; carbon dioxide is then liberated by the measured addition of excess acid and collected in 2-aminoethanol. The aminoethanol can be directly counted by the addition of a liquid scintillation cocktail. This method can be used to measure both the specific activity, (Bq/g-carbon) or the total activity of carbon-14 released from the urine sample

  6. Disentangling the drivers of coarse woody debris behavior and carbon gas emissions during fire

    Science.gov (United States)

    Zhao, Weiwei; van der Werf, Guido R.; van Logtestijn, Richard S. P.; van Hal, Jurgen R.; Cornelissen, Johannes H. C.

    2016-04-01

    The turnover of coarse woody debris, a key terrestrial carbon pool, plays fundamental roles in global carbon cycling. Biological decomposition and fire are two main fates for dead wood turnover. Compared to slow decomposition, fire rapidly transfers organic carbon from the earth surface to the atmosphere. Both a-biotic environmental factors and biotic wood properties determine coarse wood combustion and thereby its carbon gas emissions during fire. Moisture is a key inhibitory environmental factor for fire. The properties of dead wood strongly affect how it burns either directly or indirectly through interacting with moisture. Coarse wood properties vary between plant species and between various decay stages. Moreover, if we put a piece of dead wood in the context of a forest fuel bed, the soil and wood contact might also greatly affect their fire behavior. Using controlled laboratory burns, we disentangled the effects of all these driving factors: tree species (one gymnosperms needle-leaf species, three angiosperms broad-leaf species), wood decay stages (freshly dead, middle decayed, very strongly decayed), moisture content (air-dried, 30% moisture content in mass), and soil-wood contact (on versus 3cm above the ground surface) on dead wood flammability and carbon gas efflux (CO2 and CO released in grams) during fire. Wood density was measured for all coarse wood samples used in our experiment. We found that compared to other drivers, wood decay stages have predominant positive effects on coarse wood combustion (for wood mass burned, R2=0.72 when air-dried and R2=0.52 at 30% moisture content) and associated carbon gas emissions (for CO2andCO (g) released, R2=0.55 when air-dried and R2=0.42 at 30% moisture content) during fire. Thus, wood decay accelerates wood combustion and its CO2 and CO emissions during fire, which can be mainly attributed to the decreasing wood density (for wood mass burned, R2=0.91 when air-dried and R2=0.63 at 30% moisture content) as wood

  7. Cluster Decay of the High-lying excited states in $^{14}$C

    CERN Document Server

    Tian, Z Y; Li, Z H; Lin, C J; Li, Q T; Ge, Y C; Lou, J L; Jiang, W; Li, J; Yang, Z H; Feng, J; Li, P J; Chen, J; Liu, Q; Zang, H L; Yang, B; Zhang, Y; Chen, Z Q; Liu, Y; Sun, X H; Ma, J; Jia, H M; Xu, X X; Yang, L; Ma, N R; Sun, L J

    2016-01-01

    A cluster-transfer experiment of $^9\\rm{Be}(^9\\rm{Be},^{14}\\rm{C}\\rightarrow\\alpha+^{10}\\rm{Be})\\alpha$ at an incident energy of 45 MeV was carried out in order to investigate the molecular structure in high-lying resonant states in $^{14}$C. This reaction is of extremely large $Q$-value, making it an excellent case to select the reaction mechanism and the final states in outgoing nuclei. The high-lying resonances in $^{14}$C are reconstructed for three sets of well discriminated final states in $^{10}$Be. The results confirm the previous decay measurements with clearly improved decay-channel selections and show also a new state at 23.5(1) MeV. The resonant states at 22.4(3) and 24.0(3) MeV decay primarily into the typical molecular states at about 6 MeV in $^{10}$Be, indicating a well developed cluster structure in these high-lying states in $^{14}$C. Further measurements of more states of this kind are suggested.

  8. A Multiperiod Supply Chain Network Design Considering Carbon Emissions

    Directory of Open Access Journals (Sweden)

    Yang Peng

    2016-01-01

    Full Text Available This paper introduces a mixed integer linear programming formulation for modeling and solving a multiperiod one-stage supply chain distribution network design problem. The model is aimed to minimize two objectives, the total supply chain cost and the greenhouse gas emissions generated mainly by transportation and warehousing operations. The demand forecast is known for the planning horizon and shortage of demand is allowed at a penalty cost. This scenario must satisfy a minimum service level. Two carbon emission regulatory policies are investigated, the tax or carbon credit and the carbon emission cap. Computational experiments are performed to analyze the trade-offs between the total cost of the supply chain, the carbon emission quantity, and both carbon emission regulatory policies. Results demonstrate that for a certain range the carbon credit price incentivizes the reduction of carbon emissions to the environment. On the other hand, modifying the carbon emission cap inside a certain range could lead to significant reductions of carbon emission while not significantly compromising the total cost of the supply chain.

  9. Low Carbon Grid Study: Analysis of a 50% Emission Reduction in California

    Energy Technology Data Exchange (ETDEWEB)

    Brinkman, Gregory [National Renewable Energy Lab. (NREL), Golden, CO (United States); Jorgenson, Jennie [National Renewable Energy Lab. (NREL), Golden, CO (United States); Ehlen, Ali [Center for Energy Efficiency and Renewable Technologies, Sacramento, CA (United States); Caldwell, James H. [Center for Energy Efficiency and Renewable Technologies, Sacramento, CA (United States)

    2016-01-07

    The California 2030 Low Carbon Grid Study (LCGS) analyzes the grid impacts of a variety of scenarios that achieve 50% carbon emission reductions from California's electric power sector. Impacts are characterized based on several key operational and economic metrics, including production costs, emissions, curtailment, and impacts on the operation of gas generation and imports. The modeling results indicate that achieving a low-carbon grid (with emissions 50% below 2012 levels) is possible by 2030 with relatively limited curtailment (less than 1%) if institutional frameworks are flexible. Less flexible institutional frameworks and a less diverse generation portfolio could lead to higher curtailment (up to 10%), operational costs (up to $800 million higher), and carbon emissions (up to 14% higher).

  10. Terahertz emission from two-plasmon-decay induced transient currents in laser-solid interactions

    International Nuclear Information System (INIS)

    We have studied the generation of terahertz (THz) radiation via the interaction of intense femtosecond laser pulses with solid targets at a small incidence angle. It is found that preplasma with a moderate density gradient can enhance the emission. We also observe saturation of the THz output with the driving laser energy. We find that THz emission is closely related to the 3/2 harmonics of the driving laser. Particle-in-cell simulations indicate that under the present experimental conditions, the THz emission could be attributed to the transient currents at the plasma-vacuum interface, mainly formed by the two-plasmon-decay instability

  11. Terahertz emission from two-plasmon-decay induced transient currents in laser-solid interactions

    Energy Technology Data Exchange (ETDEWEB)

    Liao, G.-Q.; Li, C. [Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190 (China); Li, Y.-T., E-mail: ytli@iphy.ac.cn, E-mail: zmsheng@sjtu.edu.cn; Wang, W.-M. [Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190 (China); Collaborative Innovation Center of IFSA (CICIFSA), Shanghai Jiao Tong University, Shanghai 200240 (China); Mondal, S.; Hafez, H. A.; Fareed, M. A.; Ozaki, T. [INRS-EMT, 1650 Boulevard Lionel-Boulet, Varennes, Québec J3X 1S2 (Canada); Sheng, Z.-M., E-mail: ytli@iphy.ac.cn, E-mail: zmsheng@sjtu.edu.cn [SUPA, Department of Physics, University of Strathclyde, Glasgow G4 0NG (United Kingdom); Key Laboratory for Laser Plasmas (MoE) and Department of Physics and Astronomy, Shanghai Jiao Tong University, Shanghai 200240 (China); Collaborative Innovation Center of IFSA (CICIFSA), Shanghai Jiao Tong University, Shanghai 200240 (China); Zhang, J. [Key Laboratory for Laser Plasmas (MoE) and Department of Physics and Astronomy, Shanghai Jiao Tong University, Shanghai 200240 (China); Collaborative Innovation Center of IFSA (CICIFSA), Shanghai Jiao Tong University, Shanghai 200240 (China)

    2016-01-15

    We have studied the generation of terahertz (THz) radiation via the interaction of intense femtosecond laser pulses with solid targets at a small incidence angle. It is found that preplasma with a moderate density gradient can enhance the emission. We also observe saturation of the THz output with the driving laser energy. We find that THz emission is closely related to the 3/2 harmonics of the driving laser. Particle-in-cell simulations indicate that under the present experimental conditions, the THz emission could be attributed to the transient currents at the plasma-vacuum interface, mainly formed by the two-plasmon-decay instability.

  12. Internal W-emission and W-exchange contributions to B→D(*) decays

    International Nuclear Information System (INIS)

    We evaluate external W-emission, internal W-emission, and W-exchange contributions to nonleptonic B→D(*)π(ρ) decays based on the perturbative QCD formalism including Sudakov effects, whose ratio is found to be 1:0.3:0.05i at the amplitude level. The nonfactorizable internal W-emission contribution is included, and found to have the same order of magnitude as the factorizable one. Our predictions are consistent with the CLEO data and with those obtained by the Bauer-Stech-Wirbel method. copyright 1997 The American Physical Society

  13. Evaluation of the 1077 keV γ-ray emission probability from 68Ga decay

    International Nuclear Information System (INIS)

    68Ga decays to the excited states of 68Zn through the electron capture decay mode. New recommended values for the emission probability of 1077 keV γ-ray given by the ENSDF and DDEP databases all use data from absolute measurements. In 2011, JIANG Li-Yang deduced a new value for 1077 keV γ-ray emission probability by measuring the 69Ga(n, 2n) 68Ga reaction cross section. The new value is about 20% lower than values obtained from previous absolute measurements and evaluations. In this paper, the discrepancies among the measurements and evaluations are analyzed carefully and the new values are re-recommended. Our recommended value for the emission probability of 1077 keV γ-ray is (2.72±0.16)%. (authors)

  14. On The Economics of Forest Carbon: Renewable and Carbon Neutral But Not Emission Free

    OpenAIRE

    Lintunen, Jussi; Uusivuori, Jussi

    2014-01-01

    First-best optimal forest sector carbon policy is examined. Using a comprehensive forest sector model with a detailed carbon cycle section we show that the renewability and carbon neutrality arguments do not warrant emission free treatment of forest bioenergy. However, under the biomass stock change carbon accounting convention followed by UNFCCC and IPCC, the forest owners pay for the roundwood emissions and, to avoid double counting, the use of roundwood is treated as emission free. The bio...

  15. Structure and decay pattern of linear-chain state in 14C

    CERN Document Server

    Baba, T

    2016-01-01

    The linear-chain states of $^{14}$C are theoretically investigated by using the antisymmetrized molecular dynamics. The calculated excitation energies and the $\\alpha$ decay widths of the linear-chain states were compared with the observed data reported by the recent experiments. The properties of the positive-parity linear-chain states reasonably agree with the observation, that convinces us of the linear-chain formation in the positive-parity states. On the other hand, in the negative-parity states, it is found that the linear-chain configuration is fragmented into many states and do not form a single rotational band. As a further evidence of the linear-chain formation, we focus on the $\\alpha$ decay pattern. It is shown that the linear-chain states decay to the excited states of daughter nucleus $^{10}{\\rm Be}$ as well as to the ground state, while other cluster states dominantly decay into the ground state. Hence, we regard that this characteristic decay pattern is a strong signature of the linear-chain f...

  16. Evidence of the Exponential Decay Emission in the Swift Gamma-ray Bursts

    Science.gov (United States)

    Sakamoto, T.; Sato, G.; Hill, J.E.; Krimm, H.A.; Yamazaki, R.; Takami, K.; Swindell, S.; Osborne, J.P.

    2007-01-01

    We present a systematic study of the steep decay emission of gamma-ray bursts (GRBs) observed by the Swift X-Ray Telescope (XRT). In contrast to the analysis in recent literature, instead of extrapolating the data of Burst Alert Telescope (BAT) down into the XRT energy range, we extrapolated the XRT data up to the BAT energy range, 15-25 keV, to produce the BAT and XRT composite light curve. Based on our composite light curve fitting, we have confirmed the existence of an exponential decay component which smoothly connects the BAT prompt data to the XRT steep decay for several GRBs. We also find that the XRT steep decay for some of the bursts can be well fitted by a combination of a power-law with an exponential decay model. We discuss that this exponential component may be the emission from an external shock and a sign of the deceleration of the outflow during the prompt phase.

  17. Direct carbon dioxide emissions from civil aircraft

    Science.gov (United States)

    Grote, Matt; Williams, Ian; Preston, John

    2014-10-01

    Global airlines consume over 5 million barrels of oil per day, and the resulting carbon dioxide (CO2) emitted by aircraft engines is of concern. This article provides a contemporary review of the literature associated with the measures available to the civil aviation industry for mitigating CO2 emissions from aircraft. The measures are addressed under two categories - policy and legal-related measures, and technological and operational measures. Results of the review are used to develop several insights into the challenges faced. The analysis shows that forecasts for strong growth in air-traffic will result in civil aviation becoming an increasingly significant contributor to anthropogenic CO2 emissions. Some mitigation-measures can be left to market-forces as the key-driver for implementation because they directly reduce airlines' fuel consumption, and their impact on reducing fuel-costs will be welcomed by the industry. Other mitigation-measures cannot be left to market-forces. Speed of implementation and stringency of these measures will not be satisfactorily resolved unattended, and the current global regulatory-framework does not provide the necessary strength of stewardship. A global regulator with ‘teeth' needs to be established, but investing such a body with the appropriate level of authority requires securing an international agreement which history would suggest is going to be very difficult. If all mitigation-measures are successfully implemented, it is still likely that traffic growth-rates will continue to out-pace emissions reduction-rates. Therefore, to achieve an overall reduction in CO2 emissions, behaviour change will be necessary to reduce demand for air-travel. However, reducing demand will be strongly resisted by all stakeholders in the industry; and the ticket price-increases necessary to induce the required reduction in traffic growth-rates place a monetary-value on CO2 emissions of approximately 7-100 times greater than other common

  18. Fine structures in 14C emission of 223Ra and 224Ra

    International Nuclear Information System (INIS)

    The measurement of the energy spectrum of 14C nuclei emitted in the spontaneous radioactivity from 223Ra and 224Ra has been carried out, using thin and intense sources (480 MBq for 223Ra and 3550 MBq for 224Ra). The sources were obtained by implanting mass-separated beams from ISOLDE (CERN) into Al and vitreous C catchers. The measurement was performed with the supraconducting solenoidal spectrometer SOLENO installed at Orsay. The discovery, of a fine structure in the energy spectrum of 14C emission from 223Ra, which is analogous to the one known for α emission, is confirmed. Only 13% of the branching ratio in 14C decay leads to the ground state of the residual nucleus, while 8l% to the first excited state. For 14C emission of 224Ra, a lower limit of 2 for the hindrance factor has been measured for the transition to the first excited state in the residual nucleus. Also, a precise identification in Z with a E·ΔE telescope has been performed for the radiation from the 223Ra source. (author) 22 refs., 11 figs., 1 tab

  19. Results on decay with emission of two neutrinos or Majorons in Ge from GERDA Phase I

    Science.gov (United States)

    Agostini, M.; Allardt, M.; Bakalyarov, A. M.; Balata, M.; Barabanov, I.; Barros, N.; Baudis, L.; Bauer, C.; Becerici-Schmidt, N.; Bellotti, E.; Belogurov, S.; Belyaev, S. T.; Benato, G.; Bettini, A.; Bezrukov, L.; Bode, T.; Borowicz, D.; Brudanin, V.; Brugnera, R.; Budjáš, D.; Caldwell, A.; Cattadori, C.; Chernogorov, A.; D'Andrea, V.; Demidova, E. V.; di Vacri, A.; Domula, A.; Doroshkevich, E.; Egorov, V.; Falkenstein, R.; Fedorova, O.; Freund, K.; Frodyma, N.; Gangapshev, A.; Garfagnini, A.; Grabmayr, P.; Gurentsov, V.; Gusev, K.; Hegai, A.; Heisel, M.; Hemmer, S.; Heusser, G.; Hofmann, W.; Hult, M.; Inzhechik, L. V.; Csáthy, J. Janicskó; Jochum, J.; Junker, M.; Kazalov, V.; Kihm, T.; Kirpichnikov, I. V.; Kirsch, A.; Klimenko, A.; Knöpfle, K. T.; Kochetov, O.; Kornoukhov, V. N.; Kuzminov, V. V.; Laubenstein, M.; Lazzaro, A.; Lebedev, V. I.; Lehnert, B.; Liao, H. Y.; Lindner, M.; Lippi, I.; Lubashevskiy, A.; Lubsandorzhiev, B.; Lutter, G.; Macolino, C.; Majorovits, B.; Maneschg, W.; Medinaceli, E.; Misiaszek, M.; Moseev, P.; Nemchenok, I.; Palioselitis, D.; Panas, K.; Pandola, L.; Pelczar, K.; Pullia, A.; Riboldi, S.; Rumyantseva, N.; Sada, C.; Salathe, M.; Schmitt, C.; Schneider, B.; Schönert, S.; Schreiner, J.; Schütz, A.-K.; Schulz, O.; Schwingenheuer, B.; Selivanenko, O.; Shirchenko, M.; Simgen, H.; Smolnikov, A.; Stanco, L.; Stepaniuk, M.; Ur, C. A.; Vanhoefer, L.; Vasenko, A. A.; Veresnikova, A.; von Sturm, K.; Wagner, V.; Walter, M.; Wegmann, A.; Wester, T.; Wilsenach, H.; Wojcik, M.; Yanovich, E.; Zavarise, P.; Zhitnikov, I.; Zhukov, S. V.; Zinatulina, D.; Zuber, K.; Zuzel, G.

    2015-09-01

    A search for neutrinoless decay processes accompanied with Majoron emission has been performed using data collected during Phase I of the GERmanium Detector Array (GERDA) experiment at the Laboratori Nazionali del Gran Sasso of INFN (Italy). Processes with spectral indices were searched for. No signals were found and lower limits of the order of 10 yr on their half-lives were derived, yielding substantially improved results compared to previous experiments with Ge. A new result for the half-life of the neutrino-accompanied decay of Ge with significantly reduced uncertainties is also given, resulting in yr.

  20. Study of the deuteron emission in the $\\beta$-decay of $^{6}$He

    CERN Multimedia

    Karny, M; Tengblad, O; Riisager, K; Perkowski, J; Garcia borge, M J; Raabe, R; Kowalska, M; Fynbo, H O U; Perea martinez, A; Ter-akopian, G; Huyse, M L

    The main goal of the present proposal is to measure the continuous spectrum of deuterons emitted in the $\\beta$-decay of $^{6}$He. In particular, we want to focus on the low energy part of the spectrum, below 400 keV, which could not be accessed by all previous experiments. For the decay spectroscopy the Warsaw Optical Time Projection Chamber (OTPC) will be used. The bunches of $^{6}$He ions produced by REX-ISOLDE facility will be implanted into the active volume of the OTPC, where the rare events of deuteron emission will be recorded, practically background free.

  1. Using Carbon Emissions Data to "Heat Up" Descriptive Statistics

    Science.gov (United States)

    Brooks, Robert

    2012-01-01

    This article illustrates using carbon emissions data in an introductory statistics assignment. The carbon emissions data has desirable characteristics including: choice of measure; skewness; and outliers. These complexities allow research and public policy debate to be introduced. (Contains 4 figures and 2 tables.)

  2. Carbon dots with aggregation induced emission enhancement for visual permittivity detection.

    Science.gov (United States)

    Liu, Ze Xi; Wu, Zhu Lian; Gao, Ming Xuan; Liu, Hui; Huang, Cheng Zhi

    2016-01-26

    Photoluminescent carbon dots (CDs), hydrothermally prepared using tannic acid (TA), show visual aggregation induced emission enhancement (AIEE) properties at 455 nm when excited at 350 nm owing to the rotational hindering of the surface groups on CDs such as aromatic rings and phenolic hydroxyl ones, causing exponential decay between the ratio of the photoluminescence intensity in organic solvents to that in water and the permittivity of the solvent, and thus dazzling emissions of the CDs in the presence of solvents with small permittivity, tetrahydrofuran (THF), for instance, could be visually observed. PMID:26688276

  3. An Empirical Study on China’s Regional Carbon Emissions of Agriculture

    OpenAIRE

    Li Pang; Jingyuan Zhao

    2013-01-01

    Based on China’s carbon emissions of agriculture, the authors appraise the area differentiation of carbon emissions of agriculture; examine the influential factors of agricultural carbon emissions in China. The results show that the performance of China’s agricultural carbon emissions is on the rise. The agricultural carbon emissions in the west of China increase rapidly. The area differentiation of agricultural carbon emissions in China decreases. In general, the major driver of carbon e...

  4. Adverse effects of the automotive industry on carbon dioxide emissions

    Directory of Open Access Journals (Sweden)

    Mpho Bosupeng

    2016-05-01

    Full Text Available This study aims to determine the effects of the automotive industry on carbon dioxide emissions for the period from 1997 to 2010 for diverse economies, as well as the relationships between carbon dioxide discharges and output. The study applies cointegration and causality tests to validate these associations. The results of the Johansen cointegration test depict long-run associations between the quantity of passenger cars and carbon dioxide emissions in France, Sweden, Spain, Hungary and Japan. In addition, significant relations were observed between output and carbon dioxide discharges in Spain, Canada, India and Japan. Changes in output had substantial impact on emissions in Germany, Canada and India. The results also show that the number of passenger cars influences the magnitude of emissions in multiple economies. In conclusion, the automotive industry has to be considered in policies that aim to reduce carbon dioxide emissions.

  5. Industrial structural transformation and carbon dioxide emissions in China

    International Nuclear Information System (INIS)

    Using provincial panel data from the period 1995–2009 to analyze the relationship between the industrial structural transformation and carbon dioxide emissions in China, we find that the first-order lag of industrial structural adjustment effectively reduced the emissions; technical progress itself did not reduce the emissions, but indirectly led to decreasing emissions through the upgrading and optimization of industrial structure. Foreign direct investment and intervention by local governments reduced carbon dioxide emissions, but urbanization significantly increased the emissions. Thus, industrial structural adjustment is an important component of the development of a low-carbon economy. In the context of industrial structural transformation, an effective way to reduce a region’s carbon dioxide emissions is to promote the upgrading and optimization of industrial structure through technical progress. Tighter environmental access policies, selective utilization of foreign direct investment, and improvements in energy efficiency can help to reduce carbon dioxide emissions. - Highlights: ► Relationship between the transformation of industrial structure and CO2 emissions in China. ► Dynamic panel data model. ► Industrial structural adjustments can effectively reduce current CO2 emissions. ► Technical progress leads to decreasing CO2 emissions through upgrading of industrial structure

  6. Differential monitoring of tritium and carbon-14 compounds

    International Nuclear Information System (INIS)

    A gaseous sampling system was developed to differentially collect all major volatile forms of tritium and carbon-14 according to chemical class. These chemical forms include: tritiated forms of water, hydrogen and organics; as well as 14C-containing carbon monoxide, carbon dioxide and organics. Sampling campaigns involving the use of this differential 3H and 14C collection system have been successfully conducted at a high level liquid waste solidification plant, at a spent fuel storage facility and in the vicinity of power reactors

  7. Population Aging and Future Carbon Emissions in the United States

    OpenAIRE

    Dalton, M.G.; O'Neill, B. C.; Fuernkranz-Prskawetz, A.; Jiang, L.; Pitkin, J

    2005-01-01

    Changes in the age composition of U.S. households over the next several decades could affect energy use and carbon dioxide emissions. this article incorporates population age structure into and energy-economic growth model with multiple dynasties of heterogenous households. The model is used to estimate and compare effects of population aging and technical change on baseline paths of U.S. energy use and emissions. Results show that population aging reduces long-term carbon dioxide emissions, ...

  8. Where is it Cheapest to Cut Carbon Emissions?

    OpenAIRE

    Stern, David I.; Lambie, Neil Ross

    2010-01-01

    The relative cost of carbon emissions reductions across regions depends on whether we measure cost by marginal or total cost, private or economy-wide cost, and using market or purchasing power parity exchange rates. If all countries are on the same marginal carbon abatement cost curve then lower marginal costs of abatement are associated with higher energy intensities and higher total costs of abatement in achieving proportional cuts in emissions, equal emissions per capita, or common global ...

  9. Understanding aerospace composite components' supply chain carbon emissions

    OpenAIRE

    Chua, Mang Hann; Smyth, Beatrice M.; Murphy, Adrian; Butterfield, Joseph

    2015-01-01

    This paper examines a large structural component and its supply chain. The component is representative of that used in the production of civil transport aircraft and is manufactured from carbon fibre epoxy resin prepreg, using traditional hand layup and autoclave cure. Life cycle assessment (LCA) is used to predict the component’s production carbon emissions. The results determine the distribution of carbon emissions within the supply chain, identifying the dominant production processes as ca...

  10. Border carbon adjustments: Addressing emissions embodied in trade

    OpenAIRE

    Sakai, M; Barrett, J

    2016-01-01

    Approximately one fourth of global emissions are embodied in international trade and a significant portion flows from non-carbon-priced to carbon-priced economies. Border carbon adjustments (BCAs) figure prominently as instruments to address concerns arising from unilateral climate policy. Estimating the volume of emissions that could be potentially taxed under a BCA scheme has received little attention until now. This paper examines how a number of issues involved in the implementation of BC...

  11. Can the morphology of gamma-ray emission distinguish annihilating from decaying dark matter?

    CERN Document Server

    Boehm, Celine; Silk, Joseph

    2010-01-01

    The recent results from the PAMELA, ATIC, FERMI and HESS experiments have focused attention on the possible existence of high energy cosmic ray e^+ e^- that may originate from dark matter (DM) annihilations or decays in the Milky Way. Here we examine the morphology of the gamma-ray emission after propagation of the electrons generated by both annihilating and decaying dark matter models. We focus on photon energies of 1 GeV, 10 GeV, 50 GeV (relevant for the FERMI satellite) and consider different propagation parameters. Our main conclusion is that distinguishing annihilating from decaying dark matter may only be possible if the propagation parameters correspond to the most optimistic diffusion models. In addition, we point to examples where morphology can lead to an erroneous interpretation of the source injection energy.

  12. Biomass carbon-14 ratio measured by accelerator mass spectrometry

    International Nuclear Information System (INIS)

    Measurement methods of a biomass carbon ratio in biomass products based on 14C-radiocarbon concentration have been reviewed. Determination of the biomass carbon ratio in biomass products is important to secure the reliance in the commercial market, because the 'biomass products' could contain products from petroleum. The biomass carbon ratio can be determined from percent Modern Carbon (pMC) using ASTM D6866 methods. The pMC value is calculated from the comparison between the 14C in sample and 14C in reference material. The 14C concentration in chemical products can be measured by liquid scintillation counter (LSC) and accelerator mass spectrometry (AMS). LSC can be applicable to determine the biomass carbon ratio for liquid samples such as gasoline with bioethanol (E5 or E10). On the other hand, AMS can be used to determine the biomass carbon ratio for almost all kinds of organic and inorganic compounds such as starch, cellulose, ethanol, gasoline, or polymer composite with inorganic fillers. AMS can accept the gaseous and solid samples. The graphite derived from samples included in solid phase is measured by AMS. The biomass carbon of samples derived from wood were higher than 100% due to the effect of atomic bomb test in the atmosphere around 1950 which caused the artificial 14C injection. Exact calculation methods of the biomass carbon ratio from pMC will be required for the international standard (ISO standard). (author)

  13. Report on the workshop "Decay spectroscopy at CARIBU: advanced fuel cycle applications, nuclear structure and astrophysics". 14-16 April 2011, Argonne National Laboratory, USA.

    Energy Technology Data Exchange (ETDEWEB)

    Kondev, F.; Carpenter, M.P.; Chowdhury, P.; Clark, J.A.; Lister, C.J.; Nichols, A.L.; Swewryniak, D. (Nuclear Engineering Division); (Univ. of Massachusetts); (Univ. of Surrey)

    2011-10-06

    A workshop on 'Decay Spectroscopy at CARIBU: Advanced Fuel Cycle Applications, Nuclear Structure and Astrophysics' will be held at Argonne National Laboratory on April 14-16, 2011. The aim of the workshop is to discuss opportunities for decay studies at the Californium Rare Isotope Breeder Upgrade (CARIBU) of the ATLAS facility with emphasis on advanced fuel cycle (AFC) applications, nuclear structure and astrophysics research. The workshop will consist of review and contributed talks. Presentations by members of the local groups, outlining the status of relevant in-house projects and availabile equipment, will also be organized. time will also be set aside to discuss and develop working collaborations for future decay studies at CARIBU. Topics of interest include: (1) Decay data of relevance to AFC applications with emphasis on reactor decay heat; (2) Discrete high-resolution gamma-ray spectroscopy following radioactive decya and related topics; (3) Calorimetric studies of neutron-rich fission framgents using Total ABsorption Gamma-Ray Spectrometry (TAGS) technique; (4) Beta-delayed neutron emissions and related topics; and (5) Decay data needs for nuclear astrophysics.

  14. Carbon-14 kinetic isotope effect in the decarbonylation of lactic acid [1-14C

    International Nuclear Information System (INIS)

    The carbon-14 kinetic isotope effect for the decarbonation of lactic acid[1-14C] in sulfuric acid has been measured in the temperature interval of 20-90 deg C. The experimental values of (k12C/k14C) are compared with the theoretical 14C kinetic isotope effect calculated assuming that one carbon-oxygen stretching vibration is lost in the rate-determining step. The discrepancy between experimentally observed temperature dependence of the 14C kinetic isotope effect and the theoretical one is explained by the possible side reactions wich change the apparent degrees of decarbonylation and isotopic composition of CH3CHOHCOOH[1-14C] used in experiments aiming at the determination of carbon-14 kinetic isotope effect in the decarbonylation process itself. (author) 6 refs.; 1 tab

  15. 40 CFR Table 14 to Subpart Uuu of... - Continuous Compliance With Operating Limits for Organic HAP Emissions From Catalytic Cracking Units

    Science.gov (United States)

    2010-07-01

    ... demonstrate continuous compliance by . . . 1. Subject to NSPS for carbon monoxide (CO) in 40 CFR 60.103... to the NSPS for CO in 40 CFR 60.103 a. Continuous emission monitoring system Not applicable Complying... Limits for Organic HAP Emissions From Catalytic Cracking Units 14 Table 14 to Subpart UUU of Part...

  16. Effect of Population Structure Change on Carbon Emission in China

    Directory of Open Access Journals (Sweden)

    Wen Guo

    2016-03-01

    Full Text Available This paper expanded the Logarithmic Mean Divisia Index (LMDI model through the introduction of urbanization, residents’ consumption, and other factors, and decomposed carbon emission changes in China into carbon emission factor effect, energy intensity effect, consumption inhibitory factor effect, urbanization effect, residents’ consumption effect, and population scale effect, and then explored contribution rates and action mechanisms of the above six factors on change in carbon emissions in China. Then, the effect of population structure change on carbon emission was analyzed by taking 2003–2012 as a sample period, and combining this with the panel data of 30 provinces in China. Results showed that in 2003–2012, total carbon emission increased by 4.2117 billion tons in China. The consumption inhibitory factor effect, urbanization effect, residents’ consumption effect, and population scale effect promoted the increase in carbon emissions, and their contribution ratios were 27.44%, 12.700%, 74.96%, and 5.90%, respectively. However, the influence of carbon emission factor effect (−2.54% and energy intensity effect (−18.46% on carbon emissions were negative. Population urbanization has become the main population factor which affects carbon emission in China. The “Eastern aggregation” phenomenon caused the population scale effect in the eastern area to be significantly higher than in the central and western regions, but the contribution rate of its energy intensity effect (−11.10 million tons was significantly smaller than in the central (−21.61 million tons and western regions (−13.29 million tons, and the carbon emission factor effect in the central area (−3.33 million tons was significantly higher than that in the eastern (−2.00 million tons and western regions (−1.08 million tons. During the sample period, the change in population age structure, population education structure, and population occupation structure

  17. Carbon-14: Some evidence of migration and experiments on immobilization

    International Nuclear Information System (INIS)

    Carbon-14 that is produced in nuclear reactors by reactions on C, N and O is one of the most biologically dangerous nuclides that are subject to global dispersion (H-3, 85-Kr, 129-I). It is assumed that about 20-30% of C-14 is released to atmosphere from NPPs and 80-70% remains in the fuel and will be released during reprocessing. Atmospheric dispersion of C-14 in the form of carbon dioxide cannot go without consequence for the environment, particularly for the vegetation. This influence of the carbon-14 release from a radio-chemical facility in Russia on the nearby forest is illustrated in the first part of the report by data on C-14 concentration in the barks of trees, analyzed year by year and showing yearly variation of C-14 releases. The second part of the report deals with the study of stability of portland-cement compounds and Ca, Ba and Sr carbonates to the leaching processes. Leaching tests were done on specially prepared samples of compounds, containing various (from 30% to 70%) concentrations of Ca, Sr or Ba carbonates, tagged by C-14. Distilled water was used as leaching agent. Leaching was conducted for 46 hours and C-14 concentrations and pH of resulting waters were monitored. Differential leaching rates and leaching coefficients were analyzed and general compound behavior and its dynamics has been observed

  18. Bremsstrahlung emission probability in the {alpha} decay of {sup 210}Po

    Energy Technology Data Exchange (ETDEWEB)

    Boie, Hans-Hermann

    2009-06-03

    A high-statistics measurement of bremsstrahlung emitted in the {alpha} decay of {sup 210}Po has been performed. The measured differential emission probabilities, which could be followed up to {gamma}-energies of {proportional_to} 500 keV, allow for the first time for a serious test of various model calculations of the bremsstrahlung accompanied {alpha} decay. It is shown that corrections to the {alpha}-{gamma} angular correlation due to the interference between the electric dipole and quadrupole amplitudes and due to the relativistic character of the process have to be taken into account. With the experimentally derived angular correlation the measured energydifferential bremsstrahlung emission probabilities show excellent agreement with the fully quantum mechanical calculation. (orig.)

  19. First direct determination of the superallowed $\\beta$-decay $Q_{EC}$-value for $^{14}$O

    CERN Document Server

    Valverde, A A; Brodeur, M; Bryce, R A; Cooper, K; Eibach, M; Gulyuz, K; Izzo, C; Morrissey, D J; Redshaw, M; Ringle, R; Sandler, R; Schwarz, S; Sumithrarachchi, C S; Villari, A C C

    2015-01-01

    We report the first direct measurement of the $^{14}\\text{O}$ superallowed Fermi $\\beta$-decay $Q_{EC}$-value, the last of the so-called "traditional nine" superallowed Fermi $\\beta$-decays to be measured with Penning trap mass spectrometry. $^{14}$O, along with the other low-$Z$ superallowed $\\beta$-emitter, $^{10}$C, is crucial for setting limits on the existence of possible scalar currents. The new ground state $Q_{EC}$ value, 5144.364(25) keV, when combined with the energy of the $0^+$ daughter state, $E_x(0^+)=2312.798(11)$~keV [Nucl. Phys. A {\\bf{523}}, 1 (1991)], provides a new determination of the superallowed $\\beta$-decay $Q_{EC}$ value, $Q_{EC}(\\text{sa}) = 2831.566(28)$ keV, with an order of magnitude improvement in precision, and a similar improvement to the calculated statistical rate function $f$. This is used to calculate an improved $\\mathcal{F}t$-value of 3073.8(2.8) s.

  20. Nuclear decay by emission of charged particle-superasymmetric fission process

    International Nuclear Information System (INIS)

    The macro-microscopic method, adapted for superasymmetric fission was applied to the alpha decay and other kinds of charged particles emission which are possible due to the nuclear shell structure. Three macroscopic models (the liquid drop model, the finite range of nuclear forces model and the Yukawa exponential model) are extended for nuclear systems with different charge densities. Various numerical methods for the computation of Coulomb and surface energy of a general shape nucleus are presented along with analytical results for some particular shapes. A phenomenological correction was used to obtain the experimental Q-value. This formalism was applied to the alpha decay from the ground state and from a fission isomeric state. A time dependent Hartree-Fock method is used to estimate the zero vibration energy. A new semiempirical formula giving the best estimates for the alpha decay lifetimes was derived and used to predict new alpha emitters. For this new mode of decay intermediate between alpha decay and the traditional fission, larger probabilities are obtained for the combinations of parent-nucleus-heavy cluster leading to a magic daughter nuclei or not too far from it

  1. A Meson Emission Model of Psi to N Nbar m Charmonium Strong Decays

    CERN Document Server

    Barnes, T; Roberts, W

    2010-01-01

    In this paper we consider a sequential "meson emission" mechanism for charmonium decays of the type Psi -> N Nbar m, where Psi is a generic charmonium state, N is a nucleon and m is a light meson. This decay mechanism, which may not be dominant in general, assumes that an NNbar pair is created during charmonium annihilation, and the light meson m is emitted from the outgoing nucleon or antinucleon line. A straightforward generalization of this model can incorporate intermediate N* resonances. We derive Dalitz plot event densities for the cases Psi = eta_c, J/psi, chi_c0, chi_c1} and psi' and m = pi0, f0 and omega (and implicitly, any 0^{-+}, 0^{++} or 1^{--} final light meson). It may be possible to separate the contribution of this decay mechanism to the full decay amplitude through characteristic event densities. For the decay subset Psi -> p pbar pi0 the two model parameters are known, so we are able to predict absolute numerical partial widths for Gamma(Psi -> p pbar pi0). In the specific case J/psi -> p ...

  2. Emission probabilities of KX- and γ rays following 51CR and 67Ga Decay

    International Nuclear Information System (INIS)

    Emission probabilities of KX- and γ-rays following the decay of 5ICr and 67Ga were precisely measured with a calibrated Si(Li) detector. The photopeak efficiency Si(Li) semiconductor detector was determined experimentally for about 4-400 keV energy range by using standard sources. Results of this study have been compared with the theoretical values and other available experimental results in the literature. Good agreement was observed among our results, other available experimental results and theoretically calculated values. The standard deviations for each emission probability were calculated from the quadratic sum of the variances of the various contributions the total uncertainty

  3. Study of multi-neutron emission in the $\\beta$-decay of $^{11}$Li

    CERN Multimedia

    A new investigation of neutron emission in the $\\beta$-decay of $^{11}$Li is proposed. The principal goal of this study will be to directly measure, for the first time for any system, two $\\beta$-delayed neutrons in coincidence and determine the energy and angular correlations. This will be possible using liquid scintillator detectors, capable of distinguishing between neutrons and ambient $\\gamma$ and cosmic-rays, coupled to a new digital electronics and acquisition system. In parallel, a considerably more refined picture of the single-neutron emission will be obtained.

  4. Three accounts for regional carbon emissions from both fossil energy consumption and industrial process

    International Nuclear Information System (INIS)

    In this paper, we classify the carbon emission inventories into three perspectives through a case study in Beijing: territory account (TA), production account (PA) and consumption account (CA). A single-regional–input–output (SRIO) method was used to calculate production account and consumption account with a traditional competitive input–output (IO) table. Results show that both TA and PA have the same final values, but disparity exists at the sectoral distribution level. Both PA and CA increased from 2000 to 2007, but CA was bigger than PA and increased faster than PA. This indicates that Beijing was a carbon importer with an increasing trend. Sectoral analysis shows that “melting and pressing of metals (14)”, “Nonmetal mineral products (13)” and “Petroleum processing, coking, and nuclear fuel processing (11)” have higher direct carbon emissions from production perspective (TA), whilst “Construction” and “Service” sectors have higher emissions from consumption perspective (PA and TA). High embodied emission sectors in PA/TA, particularly the “Construction” sector, deserve more attentions for carbon emission mitigation. - Highlights: • We evaluated regional carbon emissions from three accounts perspective. • Three accounts were discussed and compared by taking Beijing as a case study. • Production account was different with territory account in sectoral distribution. • Iron and steel industries were high emission sectors from territory account. • Construction sector deserved more attentions from consumption perspective

  5. Testing JEFF-3.1.1 and ENDF/B-VII.1 Decay and Fission Yield Nuclear Data Libraries with Fission Pulse Neutron Emission and Decay Heat Experiments

    Science.gov (United States)

    Cabellos, O.; de Fusco, V.; Diez de la Obra, C. J.; Martinez, J. S.; Gonzalez, E.; Cano-Ott, D.; Alvarez-Velarde, F.

    2014-04-01

    The aim of this work is to test the present status of Evaluated Nuclear Decay and Fission Yield Data Libraries to predict decay heat and delayed neutron emission rate, average neutron energy and neutron delayed spectra after a neutron fission pulse. Calculations are performed with JEFF-3.1.1 and ENDF/B-VII.1, and these are compared with experimental values. An uncertainty propagation assessment of the current nuclear data uncertainties is performed.

  6. The preparation of glucose uniformly labelled with carbon-14

    International Nuclear Information System (INIS)

    The plant, (Zea mais, L) and culture conditions for an optimum production of glucose has been chosen. To achieve the labelling of glucose, photosynthesis and carboxylation are carried on, under an artificial atmosphere of 14CO2 produced from 14C-barium carbonate. Following photosynthesis the sugars are extracted, and then the extract purified by several methods. The purified glucose is finally, degraded and the specific radioactivity is determined in each of its carbon atoms. (Author) 37 refs

  7. The preparation of glucosa uniformly labelled with carbon-14

    International Nuclear Information System (INIS)

    The plant, (Zea mais, L) and culture conditions for an optimun production of glucose has been chosen. To achieve the labelling of glucose, photosynthesis and carboxilation are carried on under an artificial atmosphere of 14CO2 produced from 14C-barium carbonate. Following photosynthesis, the sugars are extracted and then the extract purified by several methods. The purified glucose is, finally, degraded and the specific radiactivity is determined in each of its carbon atoms. (author)

  8. Hydrodynamic aspects of carbon-14 groundwater dating

    International Nuclear Information System (INIS)

    The influence of man-made hydraulic disturbances on the 14C ages of groundwater from confined aquifers is examined, also taking into account 14C diffusion, which has an effect on 14C ages only if the hydrostatic pressure in the lower, confined aquifer is not more than 0.5m higher than that in the upper, unconfined aquifer. If the water head of the lower aquifer exceeds this value, the 14C ages of the confined groundwater are reliable. If the water head is lower, the 14C water ages rapidly approach values of a few thousand years, which no longer reflect the history of the groundwater regeneration. With regard to the palaeohydrogeological situation in Central Europe and the Central Sahara during the last 40,000 years, the 14C ages of Holocene groundwater, and the duration of the preceding hiatus of the groundwater regeneration during the last glacial period, can be determined reliably. 14C ages older than that are too small in many cases; thus, groundwater velocities derived from such data are too great. Recently operations were started to use the groundwater from confined aquifers associated with rates for lowering the water table at 0.1-0.5m/a that result in a rapid decrease in the 14C ages determined for these aquifers, delayed for one or two decades after the beginning of the withdrawal. The 3H level and the chemical content of the groundwater may also be changed after the same delay period. Changes of this kind can be used to estimate the hydraulic properties of the aquifer system. In conclusion, an interpretation of the 14C content of the groundwater from confined aquifers in terms of its age is only possible if the water head of the confined aquifer has not been lower than that of the upper aquifer for even a relatively short period. (author)

  9. IAEA advisory group meeting on nuclear structure and decay data, Zeist, The Netherlands, 11-14 May 1982

    International Nuclear Information System (INIS)

    The IAEA Nuclear Data Section convened the fifth meeting of the international nuclear structure and decay data network at Zeist near Utrecht, in The Netherlands, 11-14 May 1982. The meeting was attended by 24 scientists from 11 Member States and 2 international organizations, concerned with the compilation, evaluation, and dissemination of nuclear structure and decay data. (author)

  10. Carbon Tetrachloride Emissions from the Amazon Forest

    Science.gov (United States)

    Jardine, K.; Chambers, J. Q.; Higuchi, N.; Jardine, A. B.; Martin, S. T.; Manzi, A. O.

    2014-12-01

    As a chemically inert greenhouse gas in the troposphere with lifetimes up to 50 years but active in ozone destruction in the stratosphere, carbon tetrachloride (CCl4) plays a major role in the atmospheric chlorine budget and is widely considered strictly of anthropogenic origin deriving from numerous industrial processes and products. However, satellite remote sensing studies have shown higher concentrations at the Equator, and earlier work has suggested possible biogenic sources. Here we present highly vertically-resolved atmospheric gradients of CCl4 within and above a primary rainforest ecosystem from three towers in the Central Amazon. The observed buildup of CCl4 mixing ratios near the top of the main canopies provides new evidence for a potentially large biogenic source from the Basin. By demonstrating the need to represent tropical forests as biogenic sources of CCl4, our study may help narrow the gap between remote sensing observations of CCl4 and emission, chemistry, and transport models and therefore lead to improved predictions of its role in atmospheric chemistry and climate.

  11. Policies to reduce carbon emissions from Mexico

    International Nuclear Information System (INIS)

    The two long-term scenarios carried out for Mexico attempt to paint a picture of carbon emissions and energy use in the year 2025. The scenarios reveal that Mexico's current energy path is not optimal; the energy-intensity indicators show an increasing reliance on petroleum products and electricity over the next 40 years. Thus, Mexico must embark on a program of energy conservation in the near future. Mexico recently has undertaken several energy conservation efforts. The Mexican government implemented a National Program for Energy Modernization. This program identifies the promotion of energy conservation in Mexico as one of its top priorities between 1990 and 1994. It incorporates a number of actions geared at improving energy conservation, including: establishing pricing policies which pay special attention to electricity tariffs; setting aside budget appropriations for energy-savings programs; carrying out an energy diagnosis in the transportation and industrial sectors; promoting cogeneration and new legislation in this field; setting efficiency standards for equipment; initiating a public education campaign to inform people about energy conservation; promoting the participation of research institutes and consulting firms in the research of the technological aspects of energy-saving measures; and creating agreement with industrial and commerce associations

  12. Decay of stimulated and spontaneous emission in highly excited homoepitaxial GaN

    International Nuclear Information System (INIS)

    The high-density effects in the recombination of electron - hole plasma in photoexcited homoepitaxial GaN epilayers were studied by means of transient photoluminescence at room temperature. Owing to the 'backward' and 'lateral' photoluminescence measurement geometries employed, the influence of stimulated transitions on the decay of degenerate nonthermalized plasma was revealed. The lateral stimulated emission was demonstrated to cause a remarkable increase in the recombination rate on the early stage of the luminescence transient. A delayed enhancement of the stimulated emission due to the cooling of plasma from the initial temperature of 1100 K was observed. After completion of the thermalization process and exhaustion of the stimulated emission, the spontaneous-luminescence decay exhibited an exponential slope that relates to the nonradiative recombination of the carriers. The homoepitaxially grown GaN layer featured a luminescence decay time of 445 ps that implies a room-temperature free-carrier lifetime of 890 ps (considered to be extremely high for undoped hexagonal GaN). [copyright] 2001 American Institute of Physics

  13. Decay of stimulated and spontaneous emission in highly excited homoepitaxial GaN

    Energy Technology Data Exchange (ETDEWEB)

    Jursenas, S.; Kurilcik, N.; Kurilcik, G.; Zukauskas, A.; Prystawko, P.; Leszcynski, M.; Suski, T.; Perlin, P.; Grzegory, I.; Porowski, S.

    2001-06-11

    The high-density effects in the recombination of electron{endash}hole plasma in photoexcited homoepitaxial GaN epilayers were studied by means of transient photoluminescence at room temperature. Owing to the {open_quotes}backward{close_quotes} and {open_quotes}lateral{close_quotes} photoluminescence measurement geometries employed, the influence of stimulated transitions on the decay of degenerate nonthermalized plasma was revealed. The lateral stimulated emission was demonstrated to cause a remarkable increase in the recombination rate on the early stage of the luminescence transient. A delayed enhancement of the stimulated emission due to the cooling of plasma from the initial temperature of 1100 K was observed. After completion of the thermalization process and exhaustion of the stimulated emission, the spontaneous-luminescence decay exhibited an exponential slope that relates to the nonradiative recombination of the carriers. The homoepitaxially grown GaN layer featured a luminescence decay time of 445 ps that implies a room-temperature free-carrier lifetime of 890 ps (considered to be extremely high for undoped hexagonal GaN). {copyright} 2001 American Institute of Physics.

  14. Century-scale patterns and trends of global pyrogenic carbon emissions and fire influences on terrestrial carbon balance

    Science.gov (United States)

    Yang, Jia; Tian, Hanqin; Tao, Bo; Ren, Wei; Lu, Chaoqun; Pan, Shufen; Wang, Yuhang; Liu, Yongqiang

    2015-09-01

    Fires have consumed a large amount of terrestrial organic carbon and significantly influenced terrestrial ecosystems and the physical climate system over the past century. Although biomass burning has been widely investigated at a global level in recent decades via satellite observations, less work has been conducted to examine the century-scale changes in global fire regimes and fire influences on the terrestrial carbon balance. In this study, we investigated global pyrogenic carbon emissions and fire influences on the terrestrial carbon fluxes from 1901 to 2010 by using a process-based land ecosystem model. Our results show a significant declining trend in global pyrogenic carbon emissions between the early 20th century and the mid-1980s but a significant upward trend between the mid-1980s and the 2000s as a result of more frequent fires in ecosystems with high carbon storage, such as peatlands and tropical forests. Over the past 110 years, average pyrogenic carbon emissions were estimated to be 2.43 Pg C yr-1 (1 Pg = 1015 g), and global average combustion rate (defined as carbon emissions per unit area burned) was 537.85 g C m-2 burned area. Due to the impacts of fires, the net primary productivity and carbon sink of global terrestrial ecosystems were reduced by 4.14 Pg C yr-1 and 0.57 Pg C yr-1, respectively. Our study suggests that special attention should be paid to fire activities in the peatlands and tropical forests in the future. Practical management strategies, such as minimizing forest logging and reducing the rate of cropland expansion in the humid regions, are in need to reduce fire risk and mitigate fire-induced greenhouse gases emissions.

  15. Comparing climate policies to reduce carbon emissions in China

    International Nuclear Information System (INIS)

    Currently, China is the largest carbon emitter mainly due to growing consumption of fossil fuels. In 2009, the Chinese government committed itself to reducing domestic carbon emissions per unit of GDP by 40–45% by 2020 compared to 2005 levels. Therefore, it is a top priority for the Chinese government to adopt efficient policy instruments to reduce its carbon intensity. Against this background, this paper develops a general equilibrium model and seeks to provide empirical contributions by comparing the potential impacts of several different policy options to reduce China's carbon emissions. The main findings are as follows. Firstly, these climate policies would affect the structure of economy and contribute to carbon emissions reduction and carbon intensity reduction. Secondly, there would be significant differences in the economic and environmental effects among different climate policies and hence, the government would trade-off among different economic objectives to overcome any potential resistances. Thirdly, there would be considerable differences in the emissions effects of absolute and intensity-based carbon emissions controls, implying that the government might adopt different climate policies for absolute or intensity-based carbon emissions controls. Looking ahead, the government should trade-off among different objectives when designing climate reforms. - Highlights: • We develop a static general equilibrium model to simulate the impacts of climate policies. • We compare the potential impacts of various climate policies in China. • We discuss how to design these policies to make them more effective

  16. Transitions in pathways of human development and carbon emissions

    International Nuclear Information System (INIS)

    Countries are known to follow diverse pathways of life expectancy and carbon emissions, but little is known about factors driving these dynamics. In this letter we estimate the cross-sectional economic, demographic and geographic drivers of consumption-based carbon emissions. Using clustering techniques, countries are grouped according to their drivers, and analysed with respect to a criteria of one tonne of carbon emissions per capita and a life expectancy over 70 years (Goldemberg’s Corner). Five clusters of countries are identified with distinct drivers and highly differentiated outcomes of life expectancy and carbon emissions. Representatives from four clusters intersect within Goldemberg’s Corner, suggesting diverse combinations of drivers may still lead to sustainable outcomes, presenting many countries with an opportunity to follow a pathway towards low-carbon human development. By contrast, within Goldemberg’s Corner, there are no countries from the core, wealthy consuming nations. These results reaffirm the need to address economic inequalities within international agreements for climate mitigation, but acknowledge plausible and accessible examples of low-carbon human development for countries that share similar underlying drivers of carbon emissions. In addition, we note differences in drivers between models of territorial and consumption-based carbon emissions, and discuss interesting exceptions to the drivers-based cluster analysis. (paper)

  17. Synthesis of carbon-14 labeled Taxol (paclitaxel)

    International Nuclear Information System (INIS)

    Reductive cleavage of the C13 side chain of Taxol (1, paclitaxel) followed by regioselective silylation gave 7-triethylsilylbaccatin III (4). 3-O-Triethysilylation of 5 and subsequent reaction with benzoyl chloride-C7-14C gave azetidinone 7. Coupling of 4 and 7 followed by deprotection gave 1.26 g of Taxol-N3'-14C (11) having a specific activity of 26.5 mCi/mmol and a radiochemical purity of 95%. (author)

  18. Are emissions of black carbon from gasoline vehicles overestimated? Real-time, in situ measurement of black carbon emission factors.

    Science.gov (United States)

    Wang, Yang; Xing, Zhenyu; Zhao, Shuhui; Zheng, Mei; Mu, Chao; Du, Ke

    2016-03-15

    Accurately quantifying black carbon (BC) emission factors (EFs) is a prerequisite for estimation of BC emission inventory. BC EFs determined by measuring BC at the roadside or chasing a vehicle on-road may introduce large uncertainty for low emission vehicles. In this study, BC concentrations were measured inside the tailpipe of gasoline vehicles with different engine sizes under different driving modes to determine the respective EFs. BC EFs ranged from 0.005-7.14mg/kg-fuel under the speeds of 20-70km/h, 0.05-28.95mg/kg-fuel under the accelerations of 0.5-1.5m/s(2). Although the water vapor in the sampling stream could result in an average of 12% negative bias, the BC EFs are significantly lower than the published results obtained with roadside or chasing vehicle measurement. It is suggested to conduct measurement at the tailpipe of gasoline vehicles instead of in the atmosphere behind the vehicles to reduce the uncertainty from fluctuation in ambient BC concentration. PMID:26799329

  19. Lethal Effect on Bacterium of Decay of Incorporated Radioactive Atoms (3H, 14C, 32P)

    International Nuclear Information System (INIS)

    The biological effect of decay of 3H, 14C and 32P incorporated into a bacterium depends on the nature of the organic molecule labelled, on the position of the isotope within it and on the isotope itself. In sum, results obtained to date show that: The decay of 3H atoms incorporated into certain macromolecules of a bacterium causes sterilization through ionization by the ß- particle emitted; transmutation is of negligible importance. This self-irradiation is comparable in effect with X-rays and is affected in a similar manner by the same factors: temperature, presence of a radioprotector, radiosensitivity of the strain. Decay of 14C or 32P atoms incorporated into bacterial DNA is lethal because of the transmutation effect; ionizations produced by emitted ß- particles may be disregarded. Survival curves for 32P transmutations depend on the experimental conditions. Some of the results obtained with 32P are similar to those obtained with X-rays, e.g. effects of temperature, radical capture and oxygen, while others are similar to those of u.v. light, e.g., effect of growth conditions. Comparative tests made with 32P indicate that the recoil energy of transmutation is not the phenomenon responsible for the lethal effect observed. Comparison of the results obtained after X-irradiation or decay of 3H or 32P incorporated into the DNA of bacteria of the same strain of E. coli shows that the efficiency of a 32P transmutation is about four times greater than that of an ionization produced at random within the same DNA. (author)

  20. Carbon emissions and sequestration in forests: Case studies from seven developing countries. Volume 1, Summary: Draft

    Energy Technology Data Exchange (ETDEWEB)

    Makundi, W.; Sathaye, J. [eds.; Cerutti, O.M.

    1992-08-01

    Forests are a major source of carbon dioxide emissions in developing countries, in most cases far exceeding the emissions from the energy sector. To date, however, efforts at quantifying forestry emissions have produced a wide range of results. In order to assist policymakers in developing measures to reduce emissions` levels and to increase carbon sequestration, the Tropical Forest Research Network (F-7) has undertaken this effort to improve the precision of emissions estimates and to identify possible response options in the forestry sector. This paper summarizes the results of one component of this work. The Tropical Forest Research Network (F-7) was established in 1990 as part of the Intergovernmental Panel on Climate Change`s (IPCC) activities in examining growing emissions of greenhouse gases and their potential impact on the global climate. Unlike past methods, this study relied on a network of participants from developing countries to prepare estimates of carbon emissions. The participating countries -- Brazil, China, India, Indonesia, Malaysia, Mexico and Thailand -- currently represent an estimated two-thirds of the annual deforestation of closed moist forests. This study gives an estimate of 837 million tonnes of carbon emissions from deforestation and logging in the F-7 countries in 1990. A proportional projection of these estimates to the tropical biome shows that the total carbon emissions are between 1.1 and 1.7 billion tonnes of carbon, with a working average of 1.4 billion tonnes per year. This work also provides estimates of emissions and uptake from China, which past studies rarely have included. This summary will be followed by individual reports by each of the participating countries, which will include detailed evaluations of possible response options. Estimates for Nigeria are also under preparation.

  1. Carbon emissions and sequestration in forests: Case studies from seven developing countries

    Energy Technology Data Exchange (ETDEWEB)

    Makundi, W.; Sathaye, J. (eds.); Cerutti, O.M.

    1992-08-01

    Forests are a major source of carbon dioxide emissions in developing countries, in most cases far exceeding the emissions from the energy sector. To date, however, efforts at quantifying forestry emissions have produced a wide range of results. In order to assist policymakers in developing measures to reduce emissions' levels and to increase carbon sequestration, the Tropical Forest Research Network (F-7) has undertaken this effort to improve the precision of emissions estimates and to identify possible response options in the forestry sector. This paper summarizes the results of one component of this work. The Tropical Forest Research Network (F-7) was established in 1990 as part of the Intergovernmental Panel on Climate Change's (IPCC) activities in examining growing emissions of greenhouse gases and their potential impact on the global climate. Unlike past methods, this study relied on a network of participants from developing countries to prepare estimates of carbon emissions. The participating countries -- Brazil, China, India, Indonesia, Malaysia, Mexico and Thailand -- currently represent an estimated two-thirds of the annual deforestation of closed moist forests. This study gives an estimate of 837 million tonnes of carbon emissions from deforestation and logging in the F-7 countries in 1990. A proportional projection of these estimates to the tropical biome shows that the total carbon emissions are between 1.1 and 1.7 billion tonnes of carbon, with a working average of 1.4 billion tonnes per year. This work also provides estimates of emissions and uptake from China, which past studies rarely have included. This summary will be followed by individual reports by each of the participating countries, which will include detailed evaluations of possible response options. Estimates for Nigeria are also under preparation.

  2. Measurement of direct photon emission in the K(L) ---> pi+ pi- gamma decay mode

    Energy Technology Data Exchange (ETDEWEB)

    Abouzaid, E.; /Chicago U., EFI; Arenton, M.; /Virginia U.; Barker, A.R.; /Colorado U.; Bellantoni, L.; /Fermilab; Bellavance, A.; /Rice U.; Blucher, E.; /Chicago U., EFI; Bock,; /Fermilab; Cheu, E.; /Arizona U.; Coleman, R.; /Fermilab; Corcoran, M.D.; /Rice U.; Corti, G.; /Virginia U. /Wisconsin U., Madison

    2006-04-01

    In this paper the KTeV collaboration reports the analysis of 112.1 x 10{sup 3} candidate K{sub L} {yields} {pi}{sup +}{pi}{sup -}{gamma} decays including a background of 671 {+-} 41 events with the objective of determining the photon production mechanisms intrinsic to the decay process. These decays have been analyzed to extract the relative contributions of the Cp violating bremsstrahlung process and the CP conserving M1 and CP violating E1 direct photon emission processes. The M1 direct photon emission amplitude and its associated vector form factor parameterized as |{bar g}{sub M1}|(1 + a{sub 1}/a{sub 2}/(M{sub {rho}}{sup 2}-M{sub K}{sup 2}) + 2M{sub K}E{sub {gamma}}) have been measured to be |{bar g}{sub M1}| = 1.198 {+-} 0.035(stat) {+-} 0.086(syst) and a{sub 1}/a{sub 2} = =0.738 {+-} 0.007(stat) {+-} 0.018(syst) GeV{sup 2}/c{sup 2} respectively. An upper limit for the CP violating E1 direct emission amplitude |g{sub E1}| {le} 0.1 (90%CL) has been found. The overall ratio of direct photon emission (DE) to total photon emission including the bremsstrahlung process (IB) has been determined to be DE/(DE + IB) = 0.689 {+-} 0.021 for E{sub {gamma}} {ge} 20 MeV.

  3. Direct carbon emissions from Canadian forest fires, 1959-1999

    International Nuclear Information System (INIS)

    Fire is recognised as driving most of the boreal forest carbon balance in North America, therefore fires not only impact on carbon sequestration by forests, but emit greenhouse gases that have the potential to affect the environment. In this paper direct emissions of carbon from Canadian forest fires were estimated for all of Canada and for each ecozone for the period 1959 to 1999. Estimates were based on large fires ; fuel consumption for each fire was calculated using the Canadian Forest Fire Behaviour Prediction System. There were about 11,400 forest fires, averaging 2 x 106 hectare per year during this period. Boreal and taiga areas experienced the greatest area burned, releasing most of the carbon. The mean area-weighted fuel consumption for all fires was 2.6 kg of dry fuel per m2 (1.3 kg carbon per m2) varying from 1.8 kg to 3.9 kg per m2 among ecozones. The mean annual direct carbon emission was estimated at 27 + or - 6 Tg carbon per year, or about 18 per cent of current carbon dioxide emissions from the Canadian energy sector, on average. This excludes post-fire effects, which cause an additional loss of carbon; changes to the forest also affect the strength of the forest carbon sink. Fire emissions have shown an increase over the past two decades and are likely to remain high due to anticipated changes in fire weather resulting from climate warming. 48 refs., 3 tabs., 6 figs

  4. The carbon emissions generated in all that we consume

    International Nuclear Information System (INIS)

    The aim of the study was to increase the understanding of the fundamental drivers of carbon emissions in the UK and to show how all carbon emissions can be attributed to the delivery of products and services to meet the needs of the end consumer. From this work, it is possible to identify the products and services which have the highest carbon emissions associated with their supply chains. The study was undertaken on behalf of the Carbon Trust by the Centre for Environmental Strategy at the University of Surrey and Enviros Consulting. The analysis was based on an economic model developed at the University of Surrey, which analysed the UK's carbon emissions in terms of the total carbon embodied in consumer products and services. The results of the analysis can be cast in a variety of ways depending on the classifications used. The study starts with an analysis of the traditional production perspective and then reclassifies carbon emissions into consumption categories before combining those categories into high-level consumer needs categories. This analysis leads to the following general conclusions: From the traditional production perspective: The Electricity Production category has the highest emissions at almost 24 MtC (millions tonnes carbon per annum); The Other Land Transport category (comprising road freight, buses and coaches, taxis etc.) and the Refining Industries category have second and third highest emissions at 7.9 MtC and 7.1 MtC respectively; and The categories relating to the provision of final products and services to the consumer all have emissions of less than 2 MtC. This perspective shows total emissions of 88.1 MtC. It excludes aviation fuel emissions (11.0 MtC), domestic electricity (22.0 MtC), domestic fuel use (25.3 MtC), domestic private transport fuel use (18.3 MtC) and the UK carbon trade balance (11.7 MtC), totalling 88.3 MtC. The emissions can then be reallocated from this traditional production perspective to different consumption

  5. Beta-decay rate and beta-delayed neutron emission probability of improved gross theory

    Science.gov (United States)

    Koura, Hiroyuki

    2014-09-01

    A theoretical study has been carried out on beta-decay rate and beta-delayed neutron emission probability. The gross theory of the beta decay is based on an idea of the sum rule of the beta-decay strength function, and has succeeded in describing beta-decay half-lives of nuclei overall nuclear mass region. The gross theory includes not only the allowed transition as the Fermi and the Gamow-Teller, but also the first-forbidden transition. In this work, some improvements are introduced as the nuclear shell correction on nuclear level densities and the nuclear deformation for nuclear strength functions, those effects were not included in the original gross theory. The shell energy and the nuclear deformation for unmeasured nuclei are adopted from the KTUY nuclear mass formula, which is based on the spherical-basis method. Considering the properties of the integrated Fermi function, we can roughly categorized energy region of excited-state of a daughter nucleus into three regions: a highly-excited energy region, which fully affect a delayed neutron probability, a middle energy region, which is estimated to contribute the decay heat, and a region neighboring the ground-state, which determines the beta-decay rate. Some results will be given in the presentation. A theoretical study has been carried out on beta-decay rate and beta-delayed neutron emission probability. The gross theory of the beta decay is based on an idea of the sum rule of the beta-decay strength function, and has succeeded in describing beta-decay half-lives of nuclei overall nuclear mass region. The gross theory includes not only the allowed transition as the Fermi and the Gamow-Teller, but also the first-forbidden transition. In this work, some improvements are introduced as the nuclear shell correction on nuclear level densities and the nuclear deformation for nuclear strength functions, those effects were not included in the original gross theory. The shell energy and the nuclear deformation for

  6. Estimation and prediction of black carbon emissions in Beijing City

    Institute of Scientific and Technical Information of China (English)

    LIU Yuan; SHAO Min

    2007-01-01

    Black carbon is a by-product of incomplete combustion of carbon containing fuels. It can alter atmospheric radiation property and make adverse impacts on human health. The energy consumption in Beijing City depends largely on coal burning. Recently, Beijing City has been performing the municipal energy structure adjustment as a tool for air pollution abatement, aiming at the air quality goal for the Beijing 2008 Olympic Games. Based on Beijing energy use data in 2000, combined with emission factors of major sources of black carbon, the emission of black carbon in Beijing City is estimated to be 7.77 Gg. Coke, raw coal and biomass as non-commercial energy are the main contributors to municipal black carbon emissions. Based on Beijing energy planning in the year 2008, the emission of black carbon in 2008 will be 2.97 Gg if the contribution from biomass is not taken into account. Assuming that the black carbon emission from rural biomass in 2008 is the same as that in 2004, the biomass burning will be the largest emitter of black carbon to Beijing City in 2008.

  7. Estimation and prediction of black carbon emissions in Beijing City

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Y.; Shao, M. [Peking University, Beijing (China)

    2007-05-15

    Black carbon is a by-product of incomplete combustion of carbon containing fuels. It can alter atmospheric radiation property and make adverse impacts on human health. The energy consumption in Beijing City depends largely on coal burning. Recently, Beijing City has been performing the municipal energy structure adjustment as a tool for air pollution abatement, aiming at the air quality goal for the Beijing 2008 Olympic Games. Based on Beijing energy use data in 2000, combined with emission factors of major sources of black carbon, the emission of black carbon in Beijing City is estimated to be 7.77 Gg. Coke, raw coal and biomass as non-commercial energy are the main contributors to municipal black carbon emissions. Based on Beijing energy planning in the year 2008, the emission of black carbon in 2008 will be 2.97 Gg if the contribution from biomass is not taken into account. Assuming that the black carbon emission from rural biomass in 2008 is the same as that in 2004, the biomass burning will be the largest emitter of black carbon to Beijing City in 2008.

  8. Carbon Footprint Management of Road Freight Transport under the Carbon Emission Trading Mechanism

    Directory of Open Access Journals (Sweden)

    Jin Li

    2015-01-01

    Full Text Available Growing concern over environmental issues has considerably increased the number of regulations and legislation that aim to curb carbon emissions. Carbon emission trading mechanism, which is one of the most effective means, has been broadly adopted by several countries. This paper presents a road truck routing problem under the carbon emission trading mechanism. By introducing a calculation method of carbon emissions that considers the load and speed of the vehicle among other factors, a road truck routing optimizing model under the cap and trade mechanism based on the Travelling Salesman Problem (TSP is described. Compared with the classical TSP model that only considers the economic cost, this model suggests that the truck routing decision under the cap and trade mechanism is more effective in reducing carbon emissions. A modified tabu search algorithm is also proposed to obtain solutions within a reasonable amount of computation time. We theoretically and numerically examine the impacts of carbon trading, carbon cap, and carbon price on truck routing decision, carbon emissions, and total cost. From the results of numerical experiments, we derive interesting observations about how to control the total cost and reduce carbon emissions.

  9. Estimated Carbon Dioxide Emissions in 2008: United States

    Energy Technology Data Exchange (ETDEWEB)

    Smith, C A; Simon, A J; Belles, R D

    2011-04-01

    Flow charts depicting carbon dioxide emissions in the United States have been constructed from publicly available data and estimates of state-level energy use patterns. Approximately 5,800 million metric tons of carbon dioxide were emitted throughout the United States for use in power production, residential, commercial, industrial, and transportation applications in 2008. Carbon dioxide is emitted from the use of three major energy resources: natural gas, coal, and petroleum. The flow patterns are represented in a compact 'visual atlas' of 52 state-level (all 50 states, the District of Columbia, and one national) carbon dioxide flow charts representing a comprehensive systems view of national CO{sub 2} emissions. Lawrence Livermore National Lab (LLNL) has published flow charts (also referred to as 'Sankey Diagrams') of important national commodities since the early 1970s. The most widely recognized of these charts is the U.S. energy flow chart (http://flowcharts.llnl.gov). LLNL has also published charts depicting carbon (or carbon dioxide potential) flow and water flow at the national level as well as energy, carbon, and water flows at the international, state, municipal, and organizational (i.e. United States Air Force) level. Flow charts are valuable as single-page references that contain quantitative data about resource, commodity, and byproduct flows in a graphical form that also convey structural information about the system that manages those flows. Data on carbon dioxide emissions from the energy sector are reported on a national level. Because carbon dioxide emissions are not reported for individual states, the carbon dioxide emissions are estimated using published energy use information. Data on energy use is compiled by the U.S. Department of Energy's Energy Information Administration (U.S. EIA) in the State Energy Data System (SEDS). SEDS is updated annually and reports data from 2 years prior to the year of the update. SEDS

  10. Carbon-14 in reactor plant water

    International Nuclear Information System (INIS)

    The method for the analysis of 14C in reactor plant water and various waste streams previously used at the Idaho National Engineering Laboratory has been shown to be ineffective for samples which contain organic compounds. The previous method consisted of acidification and refluxing of the sample, precipitation of the liberated CO2, and subsequent analysis by the liquid scintillation method. The method was simple but it did not convert all compounds containing 14C in the sample to CO2. The new method, while it is based on the previous method, has been improved by employing a strong oxidant, potassium persulfate and silver nitrate, for more complete oxidation of the organics to CO2. The new method yields 14C values that have typically been one to two orders of magnitude higher than the values obtained using the former method. This indicates that most of the 14C present in the current reactor water samples being analyzed is associated with trace amounts of organics

  11. Determination of carbon-14 environmental samples by mixing 14CO2 with a liquid scintillator

    International Nuclear Information System (INIS)

    A method for the determination of Carbon-14 (14CO2) in environmental samples has been developed. The method use the direct absorption of the carbon dioxide into Carbosorb, followed with incorporation of the mixture (Carbosorb-CO2) to the liquid scintillator. The results obtained to apply this method and the benzene synthesis, usual in our laboratory, are discused and compared. The method of collection of atmospheric samples is also described. (Author)

  12. Determination of Carbon-14 in environmental samples by mixing 14CO2 with a liquid scintillator

    International Nuclear Information System (INIS)

    A method for the determination of Carbon-14 (14CO2) in environmental samples has been developed. The method use the direct absorption of the carbon dioxide into Carbosorb, followed with incorporation of the mixture (Carbosorb-CO2) to the liquid scintillator. The results obtained to apply this method and the benzene synthesis, usual in our laboratory, are discussed and compared. The method of collection of atmospheric samples is also described. (Author) 10 refs

  13. Convergence of carbon dioxide emissions in different sectors in China

    International Nuclear Information System (INIS)

    In this paper, we analyze differences in per capita carbon dioxide emissions from 1996 to 2010 in six sectors across 28 provinces in China and examine the σ-convergence, stochastic convergence and β-convergence of these emissions. We also investigate the factors that impact the convergence of per capita carbon dioxide emissions in each sector. The results show that per capita carbon dioxide emissions in all sectors converged across provinces from 1996 to 2010. Factors that impact the convergence of per capita carbon dioxide emissions in each sector vary: GDP (gross domestic product) per capita, industrialization process and population density impact convergence in the Industry sector, while GDP per capita and population density impact convergence in the Transportation, Storage, Postal, and Telecommunications Services sector. Aside from GDP per capita and population density, trade openness also impacts convergence in the Wholesale, Retail, Trade, and Catering Service sector. Population density is the only factor that impacts convergence in the Residential Consumption sector. - Highlights: • Analyze differences in CO2 emissions in six sectors among 28 provinces in China. • Examine the convergence of CO2 emissions in six sectors. • Investigate factors impact on convergence of CO2 emissions in each sector. • Factors impact on convergence of per capita CO2 emissions in each sector vary

  14. Carbon adsorption on tungsten and electronic field emission

    Science.gov (United States)

    Márquez-Mijares, Maykel; Lepetit, Bruno; Lemoine, Didier

    2016-03-01

    Electronic emission taking place at the electrodes of high voltage systems and responsible for detrimental breakdown processes is known to be strongly dependent on the cathode surface state and in particular on the presence of carbon contamination. To understand better the effect of carbon adsorption on cathode electronic emission, density functional theory calculations are reported for bulk bcc tungsten as well as for clean and carbon-covered W(100) surfaces for several coverages up to 2 ML. Adsorption geometries and energies, work functions and electronic densities of states are analyzed to assess the effect of the presence of adlayers on surface electronic field emission properties. It is shown that flat carbon adlayer deposition on clean W(100) surfaces induces an increase of the surface work function and a decrease of electronic density near the Fermi level. Both factors contribute to reducing electronic field emission levels.

  15. [Research on contribution decomposition by industry to China's carbon intensity reduction and carbon emission growth].

    Science.gov (United States)

    Jiang, Jing-Jing; Ye, Bin; Ji, Jun-Ping; Ma, Xiao-Ming

    2014-11-01

    The binding carbon intensity index and the pilot "cap-and-trade" emission trading scheme are two important approaches currently applied by China to mitigate its greenhouse gases emissions. It is of great significance to research the influence mechanism of related factors by industry on the dynamics of national carbon intensity and emission, not only for setting industry-specified intensity reduction target but also for setting industry coverage of the ETS. Two LMDI models were applied in this paper to decompose industry contributions to the changes of China's carbon intensity and carbon emission during the period of 1996-2010. Empirical results showed that: The decline of national carbon intensity was jointly determined by the changes of carbon intensities and the added value proportions of all industries, and the impact of industry carbon intensities was larger. The increase of national carbon emission was jointly determined by the changes of carbon intensities and the added value of all industries. The former had inhibitory effect whist the latter had decisive promoting effect. The five industries making the largest contribution to the changes of national carbon emission and carbon intensity included industries of electricity, nonmetal mineral, ferrous metal, transportation service, chemical materials, which were followed by the industries of agriculture, coal mining and processing, petroleum and natural gas extraction. Petroleum refining and coking industry and construction industry made small contribution to the decline of national carbon intensity, but made large contribution to the growth of national carbon emission. The contributions of service industries to national carbon emission growth showed a rising trend, especially those of transportation service industry, wholesaling, retailing and catering service industry. PMID:25639120

  16. A probabilistic analysis of cumulative carbon emissions and long-term planetary warming

    International Nuclear Information System (INIS)

    Efforts to mitigate and adapt to long-term climate change could benefit greatly from probabilistic estimates of cumulative carbon emissions due to fossil fuel burning and resulting CO2-induced planetary warming. Here we demonstrate the use of a reduced-form model to project these variables. We performed simulations using a large-ensemble framework with parametric uncertainty sampled to produce distributions of future cumulative emissions and consequent planetary warming. A hind-cast ensemble of simulations captured 1980–2012 historical CO2 emissions trends and an ensemble of future projection simulations generated a distribution of emission scenarios that qualitatively resembled the suite of Representative and Extended Concentration Pathways. The resulting cumulative carbon emission and temperature change distributions are characterized by 5–95th percentile ranges of 0.96–4.9 teratonnes C (Tt C) and 1.4 °C–8.5 °C, respectively, with 50th percentiles at 3.1 Tt C and 4.7 °C. Within the wide range of policy-related parameter combinations that produced these distributions, we found that low-emission simulations were characterized by both high carbon prices and low costs of non-fossil fuel energy sources, suggesting the importance of these two policy levers in particular for avoiding dangerous levels of climate warming. With this analysis we demonstrate a probabilistic approach to the challenge of identifying strategies for limiting cumulative carbon emissions and assessing likelihoods of surpassing dangerous temperature thresholds. (letter)

  17. A probabilistic analysis of cumulative carbon emissions and long-term planetary warming

    Science.gov (United States)

    Fyke, Jeremy; Damon Matthews, H.

    2015-11-01

    Efforts to mitigate and adapt to long-term climate change could benefit greatly from probabilistic estimates of cumulative carbon emissions due to fossil fuel burning and resulting CO2-induced planetary warming. Here we demonstrate the use of a reduced-form model to project these variables. We performed simulations using a large-ensemble framework with parametric uncertainty sampled to produce distributions of future cumulative emissions and consequent planetary warming. A hind-cast ensemble of simulations captured 1980-2012 historical CO2 emissions trends and an ensemble of future projection simulations generated a distribution of emission scenarios that qualitatively resembled the suite of Representative and Extended Concentration Pathways. The resulting cumulative carbon emission and temperature change distributions are characterized by 5-95th percentile ranges of 0.96-4.9 teratonnes C (Tt C) and 1.4 °C-8.5 °C, respectively, with 50th percentiles at 3.1 Tt C and 4.7 °C. Within the wide range of policy-related parameter combinations that produced these distributions, we found that low-emission simulations were characterized by both high carbon prices and low costs of non-fossil fuel energy sources, suggesting the importance of these two policy levers in particular for avoiding dangerous levels of climate warming. With this analysis we demonstrate a probabilistic approach to the challenge of identifying strategies for limiting cumulative carbon emissions and assessing likelihoods of surpassing dangerous temperature thresholds.

  18. Radioactive decay products in neutron star merger ejecta: heating efficiency and $\\gamma$-ray emission

    CERN Document Server

    Hotokezaka, Kenta; Tanaka, Masaomi; Bamba, Aya; Terada, Yukikatsu; Piran, Tsvi

    2015-01-01

    The radioactive decay of the freshly synthesized $r$-process nuclei ejected in compact binary mergers power optical/infrared macronovae (kilonovae) that follow these events. The light curves depend critically on the energy partition among the different products of the radioactive decay and this plays an important role in estimates of the amount of ejected $r$-process elements from a given observed signal. We study the energy partition and $\\gamma$-ray emission of the radioactive decay. We show that $20$-$50\\%$ of the total radioactive energy is released in $\\gamma$-rays on timescales from hours to a month. The number of emitted $\\gamma$-rays per unit energy interval has roughly a flat spectrum between a few dozen keV and $1$ MeV so that most of this energy is carried by $\\sim 1$ MeV $\\gamma$-rays. However at the peak of macronova emission the optical depth of the $\\gamma$-rays is $\\sim 0.02$ and most of the $\\gamma$-rays escape. The loss of these $\\gamma$-rays reduces the heat deposition into the ejecta and h...

  19. Absolute activity measurement and gamma-ray emission probability for decay of I-126

    International Nuclear Information System (INIS)

    The accurate knowledge of the gamma-ray emission probability per decay of radionuclides is important in several applications. In the case of 126 I, its importance lies mainly in fast neutron dosimetry as well as in the production of 125 I where 126 I appears as an impurity. In the present work the gamma-ray emission probabilities per decay for the 388 and 666-KeV transitions of 126 I have been measured. This radionuclide was obtained by means of the 127 I(n, 2n)126 I reaction in a fast neutron flux at the IPEN 2 MW research reactor. The methodology for the primary standardization of 126 I is described. For this purpose, two different coincidence systems were used due to the complex decay scheme of this radionuclide. The βbranch measurement was carried out in a 4 π(PC)β-γ coincidence system consisting of a proportional counter, coupled to a pair of 3'x3' Na I (Tl) crystal. The electron capture branch was measured in a X-γ coincidence system using two NaI(Tl) crystals. The gamma-ray measurements were performed in a HPGe system, previously calibrated by means of standard sources supplied by the International Atomic Energy Agency. All the uncertainties evolved were treated rigorously, by means of covariance analysis. (author)

  20. Absolute activity measurement and gamma-ray emission probability for decay of I-126

    CERN Document Server

    Fonseca, K A

    1997-01-01

    The accurate knowledge of the gamma-ray emission probability per decay of radionuclides is important in several applications. In the case of sup 1 sup 2 sup 6 I, its importance lies mainly in fast neutron dosimetry as well as in the production of sup 1 sup 2 sup 5 I where sup 1 sup 2 sup 6 I appears as an impurity. In the present work the gamma-ray emission probabilities per decay for the 388 and 666-KeV transitions of sup 1 sup 2 sup 6 I have been measured. This radionuclide was obtained by means of the sup 1 sup 2 sup 7 I(n, 2n) sup 1 sup 2 sup 6 I reaction in a fast neutron flux at the IPEN 2 MW research reactor. The methodology for the primary standardization of sup 1 sup 2 sup 6 I is described. For this purpose, two different coincidence systems were used due to the complex decay scheme of this radionuclide. The beta branch measurement was carried out in a 4 pi(PC)beta-gamma coincidence system consisting of a proportional counter, coupled to a pair of 3'x3' Na I (Tl) crystal. The electron capture branch ...

  1. Enforcement Issues in the Governance of Ships’ Carbon Emissions

    Directory of Open Access Journals (Sweden)

    Michael Bloor

    2015-07-01

    Full Text Available The shipping industry, although relatively carbon-efficient, is projected to produce rising carbon emissions in the future as a consequence of increasing world trade. A number of candidate regulations designed to mitigate these emissions have been canvassed by the UN’s International Maritime Organisation and by the European Commission. Many of these schemes are focussed on the use of market measures—emission trading schemes or fuel levies. This paper draws on observational and interview data gathered to examine enforcement issues associated with the control of ships’ sulphur emissions in order to consider the possible enforcement problems that might be associated with projected market measures to control ships’ carbon emissions. Enforcement problems are shown to be associated with the globalised character of the industry and its polycentric governance structure.

  2. Main Player in Industrial Carbon Emissions in China

    OpenAIRE

    Liu Zhenling

    2013-01-01

    The carbon emissionshas attracts great concerns in engineering technology researches. The decomposition analysis technology has been popular in the study on influencing factors of industrial carbon emissions(ICE). The change of industries’s CO2 emissions from the three main industries in China over the period 1980-2011 based on the logarithmic mean divisia index (LMDI) method has been carried out. The research indicated that economic activity effect was the main influence factor for ICE incre...

  3. Economic Growth, Carbon Dioxide Emissions, Renewable Energy and Globalization

    OpenAIRE

    Nuno Carlos LEITÃO

    2014-01-01

    This article investigates the correlation between economic growth, carbon dioxide emissions, renewable energy and globalization for the period 1970-2010, using time series (OLS,GMM, unit root test, VEC model, and Granger causality) to Portuguese economy. OLS estimator and GMM model demonstrate that carbon dioxide emissions and renewable energy are positively correlated with economic growth. The econometric models also show that the overall index of globalization has a positive effect...

  4. Spatial indeterminacy and power sector carbon emissions accounting

    Science.gov (United States)

    Jiusto, J. Scott

    Carbon emission indicators are essential for understanding climate change processes, and for motivating and measuring the effectiveness of carbon reduction policy at multiple scales. Carbon indicators also play an increasingly important role in shaping cultural discourses and politics about nature-society relations and the roles of the state, markets and civil society in creating sustainable natural resource practices and just societies. The analytical and political significance of indicators is tied closely to their objective basis: how accurately they account for the places, people, and processes responsible for emissions. In the electric power sector, however, power-trading across geographic boundaries prevents a simple, purely objective spatial attribution of emissions. Using U.S. states as the unit of analysis, three alternative methods of accounting for carbon emissions from electricity use are assessed, each of which is conceptually sound and methodologically rigorous, yet produces radically different estimates of individual state emissions. Each method also implicitly embodies distinctly different incentive structures for states to enact carbon reduction policies. Because none of the three methods can be said to more accurately reflect "true" emissions levels, I argue the best method is that which most encourages states to reduce emissions. Energy and carbon policy processes are highly contested, however, and thus I examine competing interests and perspectives shaping state energy policy. I explore what it means, philosophically and politically, to predicate emissions estimates on both objectively verifiable past experience and subjectively debatable policy prescriptions for the future. Although developed here at the state scale, the issues engaged and the carbon accounting methodology proposed are directly relevant to carbon analysis and policy formation at scales ranging from the local to the international.

  5. Adaptation of emission factors for the Tunisian carbon footprint tool

    OpenAIRE

    Dereix, Florian

    2013-01-01

    In Tunisia, the National Agency for the Environment is encouraging the creation of a carbon footprint method specifically adapted to the Tunisian context. In cooperation with the French National Agency for the Environment, the adaptation of the French carbon footprint method is realised and has to go along with an adaptation of the emission factors. In this framework, this master thesis aims at presenting the emission factors adaptation process led to adapt the accounting tool. First, a liter...

  6. Energy-Dominated Local Carbon Emissions in Beijing 2007: Inventory and Input-Output Analysis

    Directory of Open Access Journals (Sweden)

    Shan Guo

    2012-01-01

    Full Text Available For greenhouse gas (GHG emissions by Beijing economy 2007, a concrete emission inventory covering carbon dioxide (CO2, methane (CH4, and nitrous oxide (N2O is presented and associated with an input-output analysis to reveal the local GHG embodiment in final demand and trade without regard to imported emissions. The total direct GHG emissions amount to 1.06E + 08 t CO2-eq, of which energy-related CO2 emissions comprise 90.49%, non-energy-related CO2 emissions 6.35%, CH4 emissions 2.33%, and N2O emissions 0.83%, respectively. In terms of energy-related CO2 emissions, the largest source is coal with a percentage of 53.08%, followed by coke with 10.75% and kerosene with 8.44%. Sector 26 (Construction Industry holds the top local emissions embodied in final demand of 1.86E + 07 t CO2-eq due to its considerable capital, followed by energy-intensive Sectors 27 (Transport and Storage and 14 (Smelting and Pressing of Ferrous and Nonferrous Metals. The GHG emissions embodied in Beijing's exports are 4.90E + 07 t CO2-eq, accounting for 46.01% of the total emissions embodied in final demand. The sound scientific database totally based on local emissions is an important basis to make effective environment and energy policies for local decision makers.

  7. Energy-dominated local carbon emissions in Beijing 2007: inventory and input-output analysis.

    Science.gov (United States)

    Guo, Shan; Liu, J B; Shao, Ling; Li, J S; An, Y R

    2012-01-01

    For greenhouse gas (GHG) emissions by Beijing economy 2007, a concrete emission inventory covering carbon dioxide (CO(2)), methane (CH(4)), and nitrous oxide (N(2)O) is presented and associated with an input-output analysis to reveal the local GHG embodiment in final demand and trade without regard to imported emissions. The total direct GHG emissions amount to 1.06E + 08 t CO(2)-eq, of which energy-related CO(2) emissions comprise 90.49%, non-energy-related CO(2) emissions 6.35%, CH(4) emissions 2.33%, and N(2)O emissions 0.83%, respectively. In terms of energy-related CO(2) emissions, the largest source is coal with a percentage of 53.08%, followed by coke with 10.75% and kerosene with 8.44%. Sector 26 (Construction Industry) holds the top local emissions embodied in final demand of 1.86E + 07 t CO(2)-eq due to its considerable capital, followed by energy-intensive Sectors 27 (Transport and Storage) and 14 (Smelting and Pressing of Ferrous and Nonferrous Metals). The GHG emissions embodied in Beijing's exports are 4.90E + 07 t CO(2)-eq, accounting for 46.01% of the total emissions embodied in final demand. The sound scientific database totally based on local emissions is an important basis to make effective environment and energy policies for local decision makers. PMID:23193385

  8. Precise measurements of the absolute γ-ray emission probabilities of 223Ra and decay progeny in equilibrium

    International Nuclear Information System (INIS)

    Precise measurements of the absolute γ-ray emission probabilities have been made of radiochemically pure solutions of 223Ra in equilibrium with its decay progeny, which had been previously standardised by 4π(liquid scintillation)-γ digital coincidence counting techniques. Two high-purity germanium γ-ray spectrometers were used which had been accurately calibrated using a suite of primary and secondary radioactive standards. Comparison of the activity concentration determined by the primary technique against γ-ray spectrometry measurements using the nuclear data evaluations of the Decay Data Evaluation Project exhibited a range of ~18% in the most intense γ-ray emissions (>1% probability) of the 223Ra decay series. Absolute γ-ray emission probabilities and standard uncertainties have been determined for the decay of 223Ra, 219Rn, 215Po, 211Pb, 211Bi and 207Tl in equilibrium. The standard uncertainties of the measured γ-ray emission probabilities quoted in this work show a significant improvement over previously reported γ-ray emission probabilities. Correlation coefficients for pairs of the measured γ-ray emission probabilities from the decays of the radionuclides 223Ra, 219Rn and 211Pb have been determined and are presented. The α-transition probabilities of the 223Ra have been deduced from P(γ+ce) balance using the γ-ray emission probabilities determined in this work with some agreement observed with the published experimental values of the α-emission probabilities. - Highlights: • Discrepancies found within currently published γ-ray emission probabilities. • Absolute γ-ray emission probabilities of decay series in equilibrium determined. • Significant improvement in precision of measured values. • Closer agreement between deduced and experimental α transition probabilities. • Correlation coefficients presented for γ-emissions of 223Ra, 219Rn and 211Pb

  9. A study of the radiative KL→π±e-+νγ decay and search for direct photon emission with the KLOE detector

    International Nuclear Information System (INIS)

    We present a measurement of the ratio R=Γ(K0e3γ;E*γ>30 MeV, θ*γ>20 )/Γ(K0e3) and a first measurement of the direct emission contribution in semileptonic KL decays. The measurement was performed at the DAΦNEφ factory by selecting φ→KLKS decays with the KLOE detector. We use 328 pb-1 of data, corresponding to about 3.5 million K0e3 events and about 9000 K0e3γ radiative events. Our result is R=(924±23stat±16syst) x 10-5 for the branching ratio and left angle X right angle =-2.3±1.3stat±1.4syst for the effective strength parameter describing direct emission. (orig.)

  10. Beta decay and delayed proton emission of a new nuclide 59Zn

    International Nuclear Information System (INIS)

    The β+-decay of a new nuclide 59Zn has been identified by β-delayed proton and γ-ray emission. Two γ-rays and 15 proton groups have been associated with the decay of 59Zn. The total proton branching ratio was measured to be (2.3 +- 0.8) x 10-4. A half-life of 210 +- 20 ms was measured for 59Zn. The superallowed β-branch to its mirror, the Jsup(π)=3/2- ground state of 59Cu, was shown to be (93 +- 3)%. Absolute log ft values for β-transitions associated with the observed delayed proton groups were calculated and an experimental β-transition strength function was obtained. (author)

  11. Reacting to Greenhouse Gas Emissions: A Carbon Tax to Meet Emission Targets.

    OpenAIRE

    Gilbert Metcalf

    2009-01-01

    In previous papers I have described a revenue and distributionally neutral approach to reducing U.S. greenhouse gas emissions that uses a carbon tax. The revenue from the carbon tax is used to finance an environmental earned income tax credit designed to be distributionally neutral. The carbon tax reform proposal is also revenue neutral and avoids conflating carbon policy with debates over the appropriate size of the federal budget. This paper describes a variant to address concerns of enviro...

  12. Carbon dioxide emission during forest fires ignited by lightning

    OpenAIRE

    Pelc, Magdalena; Osuch, Radoslaw

    2009-01-01

    In this paper we developed the model for the carbon dioxide emission from forest fire. The master equation for the spreading of the carbon dioxide to atmosphere is the hyperbolic diffusion equation. In the paper we study forest fire ignited by lightning. In that case the fores fire has the well defined front which propagates with finite velocity.

  13. Balance and forecasts of french carbon dioxide emissions

    International Nuclear Information System (INIS)

    This paper strikes the balance of carbon dioxide emissions in France between 1986 and 1991 and gives forecasts till 2010. Since 1986, France has reduced its efforts for energy conservation and air pollution by carbon dioxide begins to growth again in connection with consumption growth in transport area, development of computer and simulation needs

  14. Assessing Carbon Dioxide Emissions from Energy Use at a University

    Science.gov (United States)

    Riddell, William; Bhatia, Krishan Kumar; Parisi, Matthew; Foote, Jessica; Imperatore, John, III

    2009-01-01

    Purpose: The purpose of this paper is to assess the carbon dioxide emissions associated with electric, HVAC, and hot water use from a US university. Design/methodology/approach: First, the total on-campus electrical, natural gas and oil consumption for an entire year was assessed. For each category of energy use, the carbon associated with…

  15. Field Emission from Carbon Nanotube/Tin Composite

    Institute of Scientific and Technical Information of China (English)

    ZHAO Bo; ZHANG Ya-fei

    2009-01-01

    Powder metallurgy was used to fabricate carbon nanotube (CNT) field emission cathodes. CNTs and tin (Sn) powder were blended, compacted and sintered. After polishing and etching, CNTs were exposed and protruded from the metal surface. CNTs were embedded into the Sn matrix, which acted as stable field emitters. The J-E curves show excellent field emission properties, such as low turn-on field of 2.8 V/μm, high emission current density and good current stability.

  16. Per Capita Carbon Dioxide Emissions: Convergence or Divergence?

    OpenAIRE

    Aldy, Joseph

    2005-01-01

    Understanding and considering the distribution of per capita carbon dioxide (CO2) emissions is important in designing international climate change proposals and incentives for participation. I evaluate historic international emissions distributions and forecast future distributions to assess whether per capita emissions have been converging or will converge. I find evidence of convergence among 23 member countries of the Organisation for Economic Co-operation and Development (OECD), whereas e...

  17. Competitive distortions, carbon emissions efficiencies or the green ultimatum?

    OpenAIRE

    Truxal, S.

    2008-01-01

    Discusses whether the US air transport industry will be obliged to reduce carbon emissions if the liberalisation of transatlantic air transport is to continue under the European Union-United States Open Skies Air Transport Agreement 2007. Considers the EU proposal to require airlines which fly to or from Europe to join the EU emissions trading scheme or a comparable national scheme under Directive 2003/87 art.25. Compares the arguments for environmental taxes or emissions trading schemes, and...

  18. Carbon-14 transfer into rice plants from a continuous atmospheric source: observations and model predictions

    International Nuclear Information System (INIS)

    Carbon-14 (14C) is one of the most important radionuclides from the perspective of dose estimation due to the nuclear fuel cycle. Ten years of monitoring data on 14C in airborne emissions, in atmospheric CO2 and in rice grain collected around the Tokai reprocessing plant (TRP) showed an insignificant radiological effect of the TRP-derived 14C on the public, but suggested a minor contribution of the TRP-derived 14C to atmospheric 14C concentrations, and an influence on 14C concentrations in rice grain at harvest. This paper also summarizes a modelling exercise (the so-called rice scenario of the IAEA's EMRAS program) in which 14C concentrations in air and rice predicted with various models using information on 14C discharge rates, meteorological conditions and so on were compared with observed concentrations. The modelling results showed that simple Gaussian plume models with different assumptions predict monthly averaged 14C concentrations in air well, even for near-field receptors, and also that specific activity and dynamic models were equally good for the prediction of inter-annual changes in 14C concentrations in rice grain. The scenario, however, offered little opportunity for comparing the predictive capabilities of these two types of models because the scenario involved a near-chronic release to the atmosphere. A scenario based on an episodic release and short-term, time-dependent observations is needed to establish the overall confidence in the predictions of environmental 14C models

  19. Composite electrode of carbon nanotubes and vitreous carbon for electron field emission

    OpenAIRE

    Matsubara, EY; Rosolen, JM; Silva, SRP

    2008-01-01

    In this work, the electron field emission behaviour of electrodes formed by carbon nanotubes (CNTs) grown onto monolithic vitreous carbon (VCarbon) substrates with microcavities is presented. Scanning electron microscopy was used to characterize the microstructure of the films. Tungsten probes, stainless steel sphere, and phosphor electrodes were employed in the electron field emission study. The CNT/VCarbon composite represents a route to inexpensive excellent large area electron emission ca...

  20. Field emission from hybrid diamond-like carbon and carbon nanotube composite structures.

    Science.gov (United States)

    Zanin, H; May, P W; Hamanaka, M H M O; Corat, E J

    2013-12-11

    A thin diamond-like carbon (DLC) film was deposited onto a densely packed "forest" of vertically aligned multiwalled carbon nanotubes (VACNT). DLC deposition caused the tips of the CNTs to clump together to form a microstructured surface. Field-emission tests of this new composite material show the typical low threshold voltages for carbon nanotube structures (2 V μm(-1)) but with greatly increased emission current, better stability, and longer lifetime. PMID:24224845

  1. Carbon dioxide emissions from international air freight

    Science.gov (United States)

    Howitt, Oliver J. A.; Carruthers, Michael A.; Smith, Inga J.; Rodger, Craig J.

    2011-12-01

    Greenhouse gas emissions from international air transport were excluded from reduction targets under the Kyoto Protocol, partly because of difficulties with quantifying and apportioning such emissions. Although there has been a great deal of recent research into calculating emissions from aeroplane operations globally, publicly available emissions factors for air freight emissions are scarce. This paper presents a methodology to calculate the amount of fuel burnt and the resulting CO 2 emissions from New Zealand's internationally air freighted imports and exports in 2007. This methodology could be applied to other nations and/or regions. Using data on fuel uplift, air freight and air craft movements, and assumptions on mean passenger loadings and the mass of passengers and air freight, CO 2 emissions factors of 0.82 kg CO 2 per t-km and 0.69 kg CO 2 per t-km for short-haul and long-haul journeys, respectively, were calculated. The total amount of fuel consumed for the international air transport of New Zealand's imports and exports was calculated to be 0.21 Mt and 0.17 Mt respectively, with corresponding CO 2 emissions of 0.67 Mt and 0.53 Mt.

  2. Hydrocarbon and carbon monoxide emissions from biomass burning in Brazil

    International Nuclear Information System (INIS)

    Field measurements of hydrocarbon emissions from biomass burning in the cerrado (grasslands) and selva (tropical forest) regions of Brazil in 1979 and 1980 are characterized and quantified here. Regional consequences of burning activities include increased background mixing ratios of carbon monoxide and ozone, as well as reduced visibility, over extensive areas. Global extrapolation of the emission rate of hydrocarbons from these fires indicates that 6 x 1013 g C of gas phase hydrocarbons and 8 x 1014 g CO may be released annually from biomass burning. These emissions contribute significantly to the global budgets of hydrocarbons and carbon monoxide

  3. Deep 1.4-GHz observations of diffuse polarized emission

    CERN Document Server

    Carretti, E; Reich, W; Reich, P; Fürst, E; Bernardi, G; Cortiglioni, S; Sbarra, C

    2006-01-01

    Polarized diffuse emission observations at 1.4-GHz in a high Galactic latitude area of the northern Celestial hemisphere are presented. The 3.2 X 3.2 deg^2 field, centred at RA = 10h 58m, Dec = +42deg 18' (B1950), has Galactic coordinates l~172deg, b~+63deg and is located in the region selected as northern target of the BaR-SPOrt experiment. Observations have been performed with the Effelsberg 100-m telescope. We find that the angular power spectra of the E- and B-modes have slopes of beta_E = -1.79 +/- 0.13 and beta_B = -1.74 +/- 0.12, respectively. Because of the very high Galactic latitude and the smooth emission, a weak Faraday rotation action is expected, which allows both a fair extrapolation to Cosmic Microwave Background Polarization (CMBP) frequencies and an estimate of the contamination by Galactic synchrotron emission. We extrapolate the E-mode spectrum up to 32-GHz and confirm the possibility to safely detect the CMBP E-mode signal in the Ka band found in another low emission region (Carretti et a...

  4. Magnetic characterization of HSLA steel by power-law decay exponents of Barkhausen emission signal

    Energy Technology Data Exchange (ETDEWEB)

    Tarafder, M. [National Metallurgical Laboratory, Mathematical Modelling and Simulation Division, Jamshedpur 831 007 (India)], E-mail: mt@nmlindia.org; Chattoraj, I. [National Metallurgical Laboratory, Mathematical Modelling and Simulation Division, Jamshedpur 831 007 (India); Nasipuri, M. [Jadavpur University, Kolkata 700032 (India); Mitra, A. [National Metallurgical Laboratory, Mathematical Modelling and Simulation Division, Jamshedpur 831 007 (India)

    2009-04-15

    The general trend of magnetic behaviour of materials is that the mechanically hard materials are also magnetically hard. However for the high strength low alloy (HSLA) steel tempered at various aging temperatures, the correlation was reported as negative. The anomaly could not be explained by the magnetic parameters like RMS voltage calculated from the Barkhausen emission signal and the coercivity from the magnetic hysteresis loop. This paper reports another magnetic parameter known as power-law decay exponent which shows excellent correlation with the mechanical properties and thus explains the progressive evolution of the microstructural constituents in HSLA steel.

  5. Magnetic characterization of HSLA steel by power-law decay exponents of Barkhausen emission signal

    Science.gov (United States)

    Tarafder, M.; Chattoraj, I.; Nasipuri, M.; Mitra, A.

    2009-04-01

    The general trend of magnetic behaviour of materials is that the mechanically hard materials are also magnetically hard. However for the high strength low alloy (HSLA) steel tempered at various aging temperatures, the correlation was reported as negative. The anomaly could not be explained by the magnetic parameters like RMS voltage calculated from the Barkhausen emission signal and the coercivity from the magnetic hysteresis loop. This paper reports another magnetic parameter known as power-law decay exponent which shows excellent correlation with the mechanical properties and thus explains the progressive evolution of the microstructural constituents in HSLA steel.

  6. Carbon dioxide emissions from biochar in soil

    DEFF Research Database (Denmark)

    Bruun, S; Clauson-Kaas, S; Bobul'ská, L;

    2014-01-01

    -sterilized soils. It emerged that carbonate may be concentrated or form during or after biochar production, resulting in significant carbonate contents. If CO2 released from carbonates in short-term experiments is misinterpreted as mineralization of biochar, the impact of this process may be significantly over...... evolution. Finally, we found that both production temperature and clay content affect biochar mineralization. As protective mechanisms hypothesized to prevent degradation of organic matter in soil usually implicate clay, we conclude that biochar is likely to be protected from mineralization during the early......The stability of biochar in soil is of importance if it is to be used for carbon sequestration and long-term improvement of soil properties. It is well known that a significant fraction of biochar is highly stable in soil, but carbon dioxide (CO2) is also released immediately after application...

  7. Soil carbon sequestration and biochar as negative emission technologies.

    Science.gov (United States)

    Smith, Pete

    2016-03-01

    Despite 20 years of effort to curb emissions, greenhouse gas (GHG) emissions grew faster during the 2000s than in the 1990s, which presents a major challenge for meeting the international goal of limiting warming to capture, enhanced weathering, bioenergy with carbon capture and storage and afforestation/deforestation, showed that all NETs have significant limits to implementation, including economic cost, energy requirements, land use, and water use. In this paper, I assess the potential for negative emissions from soil carbon sequestration and biochar addition to land, and also the potential global impacts on land use, water, nutrients, albedo, energy and cost. Results indicate that soil carbon sequestration and biochar have useful negative emission potential (each 0.7 GtCeq. yr(-1) ) and that they potentially have lower impact on land, water use, nutrients, albedo, energy requirement and cost, so have fewer disadvantages than many NETs. Limitations of soil carbon sequestration as a NET centre around issues of sink saturation and reversibility. Biochar could be implemented in combination with bioenergy with carbon capture and storage. Current integrated assessment models do not represent soil carbon sequestration or biochar. Given the negative emission potential of SCS and biochar and their potential advantages compared to other NETs, efforts should be made to include these options within IAMs, so that their potential can be explored further in comparison with other NETs for climate stabilization. PMID:26732128

  8. Energetic electron propagation in the decay phase of non-thermal flare emission

    International Nuclear Information System (INIS)

    On the basis of the trap-plus-precipitation model, the peculiarities of non-thermal emission in the decay phase of solar flares have been considered. The calculation formulas for the escape rate of trapped electrons into the loss cone in terms of time profiles of hard X-ray (HXR) and microwave (MW) emission have been obtained. It has been found that the evolution of the spectral indices of non-thermal emission depend on the regimes of the pitch angle diffusion of trapped particles into the loss cone. The properties of non-thermal electrons related to the HXR and MW emission of the solar flare on 2004 November 3 are studied with Nobeyama Radioheliograph, Nobeyama Radio Polarimeters, RHESSI, and Geostationary Operational Environmental Satellite observations. The spectral indices of non-thermal electrons related to MW and HXR emission remained constant or decreased, while the MW escape rate as distinguished from that of the HXRs increased. This may be associated with different diffusion regimes of trapped electrons into the loss cone. New arguments in favor of an important role of the superstrong diffusion for high-energy electrons in flare coronal loops have been obtained.

  9. Waste management activities and carbon emissions in Africa

    International Nuclear Information System (INIS)

    This paper summarizes research into waste management activities and carbon emissions from territories in sub-Saharan Africa with the main objective of quantifying emission reductions (ERs) that can be gained through viable improvements to waste management in Africa. It demonstrates that data on waste and carbon emissions is poor and generally inadequate for prediction models. The paper shows that the amount of waste produced and its composition are linked to national Gross Domestic Product (GDP). Waste production per person is around half that in developed countries with a mean around 230 kg/hd/yr. Sub-Saharan territories produce waste with a biogenic carbon content of around 56% (+/-25%), which is approximately 40% greater than developed countries. This waste is disposed in uncontrolled dumps that produce large amounts of methane gas. Greenhouse gas (GHG) emissions from waste will rise with increasing urbanization and can only be controlled through funding mechanisms from developed countries.

  10. Biomass and China's carbon emissions: A missing piece of carbon decomposition

    Energy Technology Data Exchange (ETDEWEB)

    Ma, Chunbo [Erb Institute for Global Sustainable Enterprise, University of Michigan, Ann Arbor, MI 48109 (United States); Stern, David I. [19/30 Watson Street, Turner, ACT 2612 (Australia)

    2008-07-15

    A number of previous studies on China's carbon emissions have mainly focused on two facts: (1) the continuous growth in emissions up till the middle of the 1990s; (2) the recent stability of emissions from 1996 to 2001. Decomposition analysis has been widely used to explore the driving forces behind these phenomena. However, since 2002, China's carbon emissions have resumed their growth at an even greater rate. This paper investigates China's carbon emissions during 1971-2003, with particular focus on the role of biomass, and the fall and resurgence in emissions since the mid-1990s. We use an extended Kaya identity and the well-established logarithmic mean Divisia index (LMDI I) method. Carbon emissions are decomposed into effects of various driving forces. We find that (1) a shift from biomass to commercial energy increases carbon emissions by a magnitude comparable to that of the increase in emissions due to population growth, (2) the technological effect and scale effect due to per-capita gross domestic products (GDP) growth are different in the pre-reform period versus the post-reform period, (3) the positive effect of population growth has been decreasing over the entire period, and (4) the fall in emissions in the late 1990s and resurgence in the early 2000s may be overstated due to inaccurate statistics. (author)

  11. Biomass and China's carbon emissions: A missing piece of carbon decomposition

    Energy Technology Data Exchange (ETDEWEB)

    Ma Chunbo [Erb Institute for Global Sustainable Enterprise, University of Michigan, Ann Arbor, MI 48109 (United States)], E-mail: cbma@bus.umich.edu; Stern, David I. [19/30 Watson Street, Turner, ACT 2612 (Australia)], E-mail: sterndavidi@yahoo.com

    2008-07-15

    A number of previous studies on China's carbon emissions have mainly focused on two facts: (1) the continuous growth in emissions up till the middle of the 1990s; (2) the recent stability of emissions from 1996 to 2001. Decomposition analysis has been widely used to explore the driving forces behind these phenomena. However, since 2002, China's carbon emissions have resumed their growth at an even greater rate. This paper investigates China's carbon emissions during 1971-2003, with particular focus on the role of biomass, and the fall and resurgence in emissions since the mid-1990s. We use an extended Kaya identity and the well-established logarithmic mean Divisia index (LMDI I) method. Carbon emissions are decomposed into effects of various driving forces. We find that (1) a shift from biomass to commercial energy increases carbon emissions by a magnitude comparable to that of the increase in emissions due to population growth, (2) the technological effect and scale effect due to per-capita gross domestic products (GDP) growth are different in the pre-reform period versus the post-reform period, (3) the positive effect of population growth has been decreasing over the entire period, and (4) the fall in emissions in the late 1990s and resurgence in the early 2000s may be overstated due to inaccurate statistics.

  12. Biomass and China's carbon emissions: A missing piece of carbon decomposition

    International Nuclear Information System (INIS)

    A number of previous studies on China's carbon emissions have mainly focused on two facts: (1) the continuous growth in emissions up till the middle of the 1990s; (2) the recent stability of emissions from 1996 to 2001. Decomposition analysis has been widely used to explore the driving forces behind these phenomena. However, since 2002, China's carbon emissions have resumed their growth at an even greater rate. This paper investigates China's carbon emissions during 1971-2003, with particular focus on the role of biomass, and the fall and resurgence in emissions since the mid-1990s. We use an extended Kaya identity and the well-established logarithmic mean Divisia index (LMDI I) method. Carbon emissions are decomposed into effects of various driving forces. We find that (1) a shift from biomass to commercial energy increases carbon emissions by a magnitude comparable to that of the increase in emissions due to population growth, (2) the technological effect and scale effect due to per-capita gross domestic products (GDP) growth are different in the pre-reform period versus the post-reform period, (3) the positive effect of population growth has been decreasing over the entire period, and (4) the fall in emissions in the late 1990s and resurgence in the early 2000s may be overstated due to inaccurate statistics

  13. A moderator ion exchange model to predict carbon-14 behaviour during operations

    International Nuclear Information System (INIS)

    Carbon-14 emissions from CANDU 6 stations are reduced through the removal of inorganic carbon ions by the ion exchange (IX) columns in the moderator purification system. A model has been developed to simulate the ion exchange behaviour of anions and cations present in the moderator. The model can be used to generate breakthrough curves for IX columns. Results from the program were compared to breakthrough curves generated by a small-scale experimental facility as well as data collected from Wolsong-3 where the IX column remained in service well past the recommended time. In both cases, the breakthrough curves were similar to the collected data. (author)

  14. Monitoring of carbon 14 in atmospheric carbon dioxide

    International Nuclear Information System (INIS)

    A purpose of this article is to present the first data of the atmospheric C-14 monitoring in CO2 form. In the Prague-Bulovka locality atmospheric CO2 have been continuously collected by absorption in 0.7 M NaOH solution. The samples were one month cumulated. Afterwards, the CO2 was extracted from the NaOH solution and benzene was synthesised. The benzene was measured by liquid scintillation counting (LSC). The monitoring results from January to July 2001 period are discussed and compared with the results from other countries. (authors)

  15. Main Player in Industrial Carbon Emissions in China

    Directory of Open Access Journals (Sweden)

    Liu Zhenling

    2013-05-01

    Full Text Available The carbon emissionshas attracts great concerns in engineering technology researches. The decomposition analysis technology has been popular in the study on influencing factors of industrial carbon emissions(ICE. The change of industries’s CO2 emissions from the three main industries in China over the period 1980-2011 based on the logarithmic mean divisia index (LMDI method has been carried out. The research indicated that economic activity effect was the main influence factor for ICE increase in China over the entire period; the decline in energy intensity and the adjustment of energy and change in the CO2 emission coefficient were major determinants for reduction of ICE. Meanwhile, we found that China had made a significant contribution to reducing global CO2 emissions by decreasing its energy intensity. Based on the fore study, the mechanism of CO2 emission changes has been analyzed and the pressure-driven environment protection model has been put forward.

  16. Scenario analysis on the goal of carbon emission peaking around 2030 of China proposed in the China-U.S. joint statement on climate change

    Science.gov (United States)

    Zheng, T.

    2015-12-01

    A goal of carbon (C) emission peaking around 2030 of China was declared in the China-U.S. joint statement on climate change, and emphasized in China's intended nationally determined contributions (INDC). Here, we predicted the carbon emission of China during the period 2011~2050 under seven scenarios, and analyzed the scientific and social implications of realizing the goal. Our results showed that: (1) C emissions of China will reach their peaks at 2022~2045 (with peak values 3.15~5.10 Pg C), and the predicted decay rates of C intensity were 2.1~4.2% in 2011~2050; (2) the precondition that the national C emission reaches the peak before 2030 is that the annual decay rates of C intensity must exceed 3.3% , as decay rates under different scenarios were predicted higher than that except for Past G8 scenario; (3) the national C emission would reach the peak before 2030, if the government of China should realize the C emissions reduction goals of China's 12th five-year plan, climate commitments of Copenhagen and INDC; (4) Chinese government could realize the goal of C emission peaking around 2030 from just controlling C emission intensity , but associated with relatively higher government's burden. In summary, China's C emission may well peak before 2030, meanwhile the combination of emissions reduction and economic macro-control would be demanded to avoid heavier social pressure of C emissions reduction occurred.

  17. Disentangling the contribution of multiple land covers to fire-mediated carbon emissions in Amazonia during the 2010 drought

    Science.gov (United States)

    Anderson, Liana Oighenstein; Aragão, Luiz E. O. C.; Gloor, Manuel; Arai, Egídio; Adami, Marcos; Saatchi, Sassan S.; Malhi, Yadvinder; Shimabukuro, Yosio E.; Barlow, Jos; Berenguer, Erika; Duarte, Valdete

    2015-10-01

    In less than 15 years, the Amazon region experienced three major droughts. Links between droughts and fires have been demonstrated for the 1997/1998, 2005, and 2010 droughts. In 2010, emissions of 510 ± 120 Tg C were associated to fire alone in Amazonia. Existing approaches have, however, not yet disentangled the proportional contribution of multiple land cover sources to this total. We develop a novel integration of multisensor and multitemporal satellite-derived data on land cover, active fires, and burned area and an empirical model of fire-induced biomass loss to quantify the extent of burned areas and resulting biomass loss for multiple land covers in Mato Grosso (MT) state, southern Amazonia—the 2010 drought most impacted region. We show that 10.77% (96,855 km2) of MT burned. We estimated a gross carbon emission of 56.21 ± 22.5 Tg C from direct combustion of biomass, with an additional 29.4 ± 10 Tg C committed to be emitted in the following years due to dead wood decay. It is estimated that old-growth forest fires in the whole Brazilian Legal Amazon (BLA) have contributed to 14.81 Tg of C (11.75 Tg C to 17.87 Tg C) emissions to the atmosphere during the 2010 fire season, with an affected area of 27,555 km2. Total C loss from the 2010 fires in MT state and old-growth forest fires in the BLA represent, respectively, 77% (47% to 107%) and 86% (68.2% to 103%) of Brazil's National Plan on Climate Change annual target for Amazonia C emission reductions from deforestation.

  18. Evaluation of carbon-14 life cycle in reactors VVER-1000

    International Nuclear Information System (INIS)

    This work is aimed at the evaluation of carbon-14 life cycle in light water reactors VVER-1000. Carbon-14 is generated as a side product in different systems of nuclear reactors and has been an issue not only in radioactive waste management but mainly in release into the environment in the form of gaseous effluents. The principal sources of this radionuclide are in primary cooling water and fuel. Considerable amount of C-14 is generated by neutron reactions with oxygen 17O and nitrogen 14N present in water coolant and fuel. The reaction likelihood and consequently volume of generated radioisotope depends on several factors, especially on the effective cross-section, concentrations of parent elements and conditions of power plant operating strategies. Due to its long half-life and high capability of integration into the environment and thus into the living species, it is very important to monitor the movement of carbon-14 in all systems of nuclear power plant and to manage its release out of NPP. The dominant forms of radioactive carbon-14 are the hydrocarbons owing to the combinations with hydrogen used for absorption of radiolytic oxygen. These organic compounds, such as formaldehyde, methyl alcohol, ethyl alcohol and formic acid can be mostly retained on ion exchange resins used in the system for purifying primary cooling water. The gaseous carbon compounds (CH4 and CO2) are released into the atmosphere via the ventilation systems of NPP. Based on the information and data obtained from different sources, it has been designed a balance model of possible carbon-14 pathways throughout the whole NPP. This model includes also mass balance model equations for each important node in system and available sampling points which will be the background for further calculations. This document is specifically not to intended to describe the best monitoring program attributes or technologies but rather to provide evaluation of obtained data and find the optimal way to upgrade

  19. Monopolistic Sequestration of European Carbon Emissions

    OpenAIRE

    Niko Jaakkola

    2013-01-01

    Mitigating climate change by carbon capture and storage (CCS) will require vast infrastructure investments. These investments include pipeline networks for transporting carbon dioxide (CO2) from industrial sites ('sources') to the storage sites ('sinks'). This paper considers the decentralised formation of trunk-line networks when geological storage space is exhaustible and demand is increasing. Monopolistic control of an exhaustible resource may lead to overinvestment and/or excessively earl...

  20. Green emission in carbon doped ZnO films

    Energy Technology Data Exchange (ETDEWEB)

    Tseng, L. T.; Yi, J. B., E-mail: jiabao.yi@unsw.edu.au; Zhang, X. Y.; Xing, G. Z.; Luo, X.; Li, S. [School of Materials Science and Engineering, University of New South Wales, Kensington, NSW, 2052 (Australia); Fan, H. M. [School of Chemical Engineering, Northwest University, Xi' an 710069 (China); Herng, T. S.; Ding, J. [Department of Materials Science and Engineering, National University of Singapore, 119260 (Singapore); Ionescu, M. [Australian Nuclear Science and Technology Organization, (ANSTO), New Illawarra Road, Lucas Heights, NSW 2234 (Australia)

    2014-06-15

    The emission behavior of C-doped ZnO films, which were prepared by implantation of carbon into ZnO films, is investigated. Orange/red emission is observed for the films with the thickness of 60–100 nm. However, the film with thickness of 200 nm shows strong green emission. Further investigations by annealing bulk ZnO single crystals under different environments, i.e. Ar, Zn or C vapor, indicated that the complex defects based on Zn interstitials are responsible for the strong green emission. The existence of complex defects was confirmed by electron spin resonance (ESR) and low temperature photoluminescence (PL) measurement.

  1. Monthly, global emissions of carbon dioxide from fossil fuel consumption

    DEFF Research Database (Denmark)

    Andres, R.J.; Gregg, Jay Sterling; Losey, L.;

    2011-01-01

    This paper examines available data, develops a strategy and presents a monthly, global time series of fossil-fuel carbon dioxide emissions for the years 1950–2006. This monthly time series was constructed from detailed study of monthly data from the 21 countries that account for approximately 80......% of global total emissions. These data were then used in a Monte Carlo approach to proxy for all remaining countries. The proportional-proxy methodology estimates by fuel group the fraction of annual emissions emitted in each country and month. Emissions from solid, liquid and gas fuels are explicitly...

  2. Green emission in carbon doped ZnO films

    Directory of Open Access Journals (Sweden)

    L. T. Tseng

    2014-06-01

    Full Text Available The emission behavior of C-doped ZnO films, which were prepared by implantation of carbon into ZnO films, is investigated. Orange/red emission is observed for the films with the thickness of 60–100 nm. However, the film with thickness of 200 nm shows strong green emission. Further investigations by annealing bulk ZnO single crystals under different environments, i.e. Ar, Zn or C vapor, indicated that the complex defects based on Zn interstitials are responsible for the strong green emission. The existence of complex defects was confirmed by electron spin resonance (ESR and low temperature photoluminescence (PL measurement.

  3. Carbon emissions from tropical forest degradation caused by logging

    International Nuclear Information System (INIS)

    The focus of land-use related efforts in developing countries to reduce carbon emissions has been on slowing deforestation, yet international agreements are to reduce emissions from both deforestation and forest degradation (REDD). The second ‘D’ is poorly understood and accounted for a number of technical and policy reasons. Here we introduce a complete accounting method for estimating emission factors from selective timber harvesting, a substantial form of forest degradation in many tropical developing countries. The method accounts separately for emissions from the extracted log, from incidental damage to the surrounding forest, and from logging infrastructure, and emissions are expressed as units of carbon per cubic meter of timber extracted to allow for simple application to timber harvesting statistics. We applied the method in six tropical countries (Belize, Bolivia, Brazil, Guyana, Indonesia, and Republic of Congo), resulting in total emission factors of 0.99−2.33 Mg C m−3. In all cases, emissions were dominated by damage to surrounding vegetation and the infrastructure rather than the logs themselves, and total emissions represented about 3–15% of the biomass carbon stocks of the associated unlogged forests. We then combined the emission factors with country level logging statistics for nine key timber producing countries represented by our study areas to gain an understanding of the order of magnitude of emissions from degradation compared to those recently reported for deforestation in the same countries. For the nine countries included, emissions from logging were on average equivalent to about 12% of those from deforestation. For those nine countries with relatively low emissions from deforestation, emissions from logging were equivalent to half or more of those from deforestation, whereas for those countries with the highest emissions from deforestation, emissions from logging were equivalent to <10% of those from deforestation

  4. Enhanced γ -Ray Emission from Neutron Unbound States Populated in β Decay

    Science.gov (United States)

    Tain, J. L.; Valencia, E.; Algora, A.; Agramunt, J.; Rubio, B.; Rice, S.; Gelletly, W.; Regan, P.; Zakari-Issoufou, A.-A.; Fallot, M.; Porta, A.; Rissanen, J.; Eronen, T.; ńystö, J.; Batist, L.; Bowry, M.; Bui, V. M.; Caballero-Folch, R.; Cano-Ott, D.; Elomaa, V.-V.; Estevez, E.; Farrelly, G. F.; Garcia, A. R.; Gomez-Hornillos, B.; Gorlychev, V.; Hakala, J.; Jordan, M. D.; Jokinen, A.; Kolhinen, V. S.; Kondev, F. G.; Martínez, T.; Mendoza, E.; Moore, I.; Penttilä, H.; Podolyák, Zs.; Reponen, M.; Sonnenschein, V.; Sonzogni, A. A.

    2015-08-01

    Total absorption spectroscopy is used to investigate the β -decay intensity to states above the neutron separation energy followed by γ -ray emission in Br,8887 and 94Rb. Accurate results are obtained thanks to a careful control of systematic errors. An unexpectedly large γ intensity is observed in all three cases extending well beyond the excitation energy region where neutron penetration is hindered by low neutron energy. The γ branching as a function of excitation energy is compared to Hauser-Feshbach model calculations. For 87Br and 88Br the γ branching reaches 57% and 20%, respectively, and could be explained as a nuclear structure effect. Some of the states populated in the daughter can only decay through the emission of a large orbital angular momentum neutron with a strongly reduced barrier penetrability. In the case of neutron-rich 94Rb the observed 4.5% branching is much larger than the calculations performed with standard nuclear statistical model parameters, even after proper correction for fluctuation effects on individual transition widths. The difference can be reconciled by introducing an enhancement of 1 order of magnitude in the photon strength to neutron strength ratio. An increase in the photon strength function of such magnitude for very neutron-rich nuclei, if it proves to be correct, leads to a similar increase in the (n ,γ ) cross section that would have an impact on r process abundance calculations.

  5. Activity measurements and gamma emission intensities determination in the decay of Zn65

    International Nuclear Information System (INIS)

    Over the last twenty years, a number of laboratories have participated to the Systeme International de Reference (SIR BIPM) and it appeared that the mass activity of 65Zn determined by the gamma-ray spectrometry was less by about 2% than the one determined by using 4πβ-γ coincidence counting. An international exercise EUROMET, action 721, was organized with the objective of improving the knowledge of decay data in the 65Zn disintegration. Nine laboratories participated, sending results for the activity measurement and the 1115 keV gamma emission intensity. For the activity measurement, the participants used the 4πβ-γ coincidence method mainly, resulting values and uncertainty budgets are described. From the new gamma emission intensities measured in this exercise and, taking into account previous published values, the intensity of the 1115 keV gamma emission has been determined being equal to: 50.22 (11) %. This new value must lead to derive activity values higher than those previously obtained, reducing the difference, with other techniques of measurement, to 1 %. Moreover, the uncertainty on the emission intensity value has been divided by a factor of two. (authors)

  6. Alternative industrial carbon emissions benchmark based on input-output analysis

    Science.gov (United States)

    Han, Mengyao; Ji, Xi

    2016-05-01

    Some problems exist in the current carbon emissions benchmark setting systems. The primary consideration for industrial carbon emissions standards highly relate to direct carbon emissions (power-related emissions) and only a portion of indirect emissions are considered in the current carbon emissions accounting processes. This practice is insufficient and may cause double counting to some extent due to mixed emission sources. To better integrate and quantify direct and indirect carbon emissions, an embodied industrial carbon emissions benchmark setting method is proposed to guide the establishment of carbon emissions benchmarks based on input-output analysis. This method attempts to link direct carbon emissions with inter-industrial economic exchanges and systematically quantifies carbon emissions embodied in total product delivery chains. The purpose of this study is to design a practical new set of embodied intensity-based benchmarks for both direct and indirect carbon emissions. Beijing, at the first level of carbon emissions trading pilot schemes in China, plays a significant role in the establishment of these schemes and is chosen as an example in this study. The newly proposed method tends to relate emissions directly to each responsibility in a practical way through the measurement of complex production and supply chains and reduce carbon emissions from their original sources. This method is expected to be developed under uncertain internal and external contexts and is further expected to be generalized to guide the establishment of industrial benchmarks for carbon emissions trading schemes in China and other countries.

  7. Field emission properties of the graphenated carbon nanotube electrode

    Energy Technology Data Exchange (ETDEWEB)

    Zanin, H., E-mail: hudson.zanin@bristol.ac.uk [School of Chemistry, University of Bristol, Bristol BS8 1TS (United Kingdom); Faculdade de Engenharia Elétrica e Computação, Departamento de Semicondutores, Instrumentos e Fotônica, Universidade Estadual de Campinas, UNICAMP, Av. Albert Einstein N. 400, CEP 13 083-852 Campinas, São Paulo (Brazil); Ceragioli, H.J.; Peterlevitz, A.C.; Baranauskas, Vitor [Faculdade de Engenharia Elétrica e Computação, Departamento de Semicondutores, Instrumentos e Fotônica, Universidade Estadual de Campinas, UNICAMP, Av. Albert Einstein N. 400, CEP 13 083-852 Campinas, São Paulo (Brazil); Marciano, F.R.; Lobo, A.O. [Laboratory of Biomedical Nanotechnology/Institute of Research and Development at UNIVAP, Av. Shishima Hifumi, 2911, CEP 12244-000 Sao Jose dos Campos, SP (Brazil)

    2015-01-01

    Graphical abstract: - Highlights: • Facile method to prepare graphenated carbon nanotubes (g-CNTs). • The electric field emission behaviour of g-CNTs was studied. • g-CNTs show better emission current stability than non-graphenated CNTs. - Abstract: Reduced graphene oxide-coated carbon nanotubes (RGO-CNT) electrodes have been prepared by hot filament chemical vapour deposition system in one-step growth process. We studied RGO-CNT electrodes behaviour as cold cathode in field emission test. Our results show that RGO-CNT retain the low threshold voltage typical of CNTs, but with greatly improved emission current stability. The field emission enhancement value is significantly higher than that expected being caused by geometric effect (height divided by the radius of nanotube). This suggested that the field emission of this hybrid structure is not only from a single tip, but eventually it is from several tips with contribution of graphene nanosheets at CNT's walls. This phenomenon explains why the graphenated carbon nanotubes do not burn out as quickly as CNT does until emission ceases completely. These preliminaries results make nanocarbon materials good candidates for applications as electron sources for several devices.

  8. Emissions to air in Sweden: carbon dioxide, methane, nitrous oxide, nitrogen oxides, carbon monoxide, volatile organic compounds and sulphur dioxide 1990-2000

    International Nuclear Information System (INIS)

    Greenhouse gases - Carbon dioxide from combustion and motor fuels, Methane and Laughing gas from agriculture Carbon dioxide (CO2) emissions in Sweden amounted to 56 million tonnes in 2000, which is minor decrease since 1990. Combustion of fossil fuels and the use of fuels in vehicles are the major sources of CO2 emissions. Methane is the second most important greenhouse gas, and it is emitted when bacteria degrade organic matter. In Sweden the main source is enteric fermentation from cattle. The emissions of methane were 324 000 tonnes 1990. In 2000 the emissions amounted to 280 000 tonnes, or a 14 per cent decrease. The third greenhouse gas, N2O is mostly emitted from agriculture. N2O emissions have fallen somewhat. Total emissions of sulphur dioxide (SO2) and nitrogen oxides (NOx, counted as NO2) in Sweden were 58,000 and 247,000 tonnes respectively in 2000. International air and maritime traffic is not included. The major source of SO2 emissions is combustion of fossil fuels. Road traffic is the major source of NOX emissions. Emissions of carbon monoxide (CO) and non-methane volatile organic compounds (NMVOCs) are also presented in this report. The main source of CO is road traffic, while NMVOCs come from household combustion and road traffic. Emission trends for fluoride carbon greenhouse gases HFCs, PFCs and SF6 are also presented. These gases mainly emit from refrigerators, freezing and air conditioning equipment (e.g. in cars and buildings) and from heat pumps

  9. Carbon-14 geochemistry at the Savannah River Site

    Energy Technology Data Exchange (ETDEWEB)

    Roberts, Kimberly A.; Kaplan, Daniel I.

    2013-05-10

    Carbon-14 is among the key radionuclides driving risk at the E-Area Low-Level Waste Disposal Facility on the Savannah River Site (SRS). Much of this calculated risk is believed to be the result of having to make conservative assumptions in risk calculations because of the lack of site-specific data. The original geochemical data package (Kaplan 2006) recommended that performance assessments and composite analyses for the SRS assume that {sup 14}C did not sorbed to sediments or cementitious materials, i.e., that C-14 K{sub d} value (solid:liquid concentration ratio) be set to 0 mL/g (Kaplan 2006). This recommendation was based primarily on the fact that no site-specific experimental work was available and the assumption that the interaction of anionic {sup 14}C as CO{sub 2}{sup 2-}) with similarly charged sediments or cementitious materials would be minimal. When used in reactive transport equations, the 0 mL/g Kd value results in {sup 14}C not interacting with the solid phase and moving quickly through the porous media at the same rate as water. The objective of this study was to quantify and understand how aqueous {sup 14}C, as dissolved carbonate, sorbs to and desorbs from SRS sediments and cementitious materials. Laboratory studies measuring the sorption of {sup 14}C, added as a carbonate, showed unequivocally that {sup 14}C-carbonate K{sub d} values were not equal to 0 mL/g for any of the solid phases tested, but they required several months to come to steady state. After six months of contact, the apparent K{sub d} values for a clayey sediment was 3,000 mL/g, for a sandy sediment was 10 mL/g, for a 36-year-old concrete was 30,000 mL/g, and for a reducing grout was 40 mL/g. Furthermore, it was demonstrated that (ad)sorption rates were appreciably faster than desorption rates, indicating that a kinetic sorption model, as opposed to the steady-state K{sub d} model, may be a more accurate description of the {sup 14}C-carbonate sorption process. A second study

  10. Polycyclic aromatic hydrocarbons, elemental and organic carbon emissions from tire-wear.

    Science.gov (United States)

    Aatmeeyata; Sharma, Mukesh

    2010-09-15

    Tire-wear is an important source of PAHs, elemental carbon (EC) and organic carbon (OC). The emissions of these pollutants have been studied in an experimental set-up, simulating a realistic road-tire interaction (summer tire-concrete road). The large particle non-exhaust emissions (LPNE; diameter greater than 10 microm) have been evaluated over 14,500 km run of the tire. An increasing linear trend with cumulative km run was observed for emissions of PAHs and carbon. Amongst PAHs in LPNE, pyrene has been observed to be the highest (30+/-4 mg kg(-1)) followed by benzo[ghi]perylene (17+/-2 mg kg(-1)). Different fractions of EC-OC for tire-wear have been analyzed, and unlike exhaust emissions, EC1 was observed to be 99% of EC whereas more than 70% of the OC was the high temperature carbon (OC3 and OC4). The overall emission factors (mass tire(-1) km(-1)) for PAHs, EC and OC from tire-wear are 378 ng tire(-1) km(-1), 1.46 mg tire(-1) km(-1) and 2.37 mg tire(-1) km(-1) for small cars. PMID:20624631

  11. Is there cross-country convergence in carbon dioxide emissions?

    International Nuclear Information System (INIS)

    This paper examines the spatial distribution of per capita carbon dioxide emissions in 87 countries during the period 1960-1999. In order to overcome the methodological limitations of conventional convergence analysis, I have used a non-parametric approach which allows us to study the dynamics of the entire cross-section distribution. The results show that cross-country disparities in per capita carbon dioxide emissions decreased throughout the study period. In fact, the probability mass concentrated around the average increased over time, which helps to explain the observed reduction in the polarisation of the distribution under consideration. In any event, the intradistribution mobility level is relatively low. I have also investigated how far spatial differences in per capita carbon dioxide emission levels can be explained by factors such as per capita income, the degree of trade openness or climatic conditions

  12. Analytical optimization for field emission of carbon nanotube array

    Institute of Scientific and Technical Information of China (English)

    WANG XinQing; LI Liang; CHEN Min; JIN HongXiao; JIN DingFeng; PENG Min; GE HongLiang

    2009-01-01

    To optimize field emission (FE) property of carbon nanotube (CNT) array on a planar cathode surface,the Fowler-Nordheim formula has been used to discuss the maximum of the emission current density with the floating sphere model in this paper. The emission current density is dominating as the ane-lytical Fowler-Nordheim function of the intertube distance, and the maximum of the emission current density is deduced and discussed. The results indicate that the intertube distance in CNT array criti-cally affects the field enhancement factor and the emission current density, whose maximum occurs at the intertube distance approximating a tenth of the tube height. Considering the emission current den-sity and the field enhancement factor, the FE can be optimized analytically when the intertube distance is about a tenth of the tube height.

  13. Equity and carbon emissions trading: a model analysis

    International Nuclear Information System (INIS)

    Carbon emissions trading is a key instrument of climate policy. It helps to bring about emission reductions in that place where they are least costly. However, fair burden sharing is about more than just cost-efficiency. While focussing on the instrument of emissions trading, this paper touches upon equity issues that frame decisions on emission rights allocation. The analysis is based on the ICLIPS model. The model study gives new insights on how the equal per capita allocation principle influences the intertemporal emission paths and about the distribution of mitigation costs in the long run. Apart from the intuitive economic evaluation of model results, this paper also attempts to provide an evaluation from an equity point of view. For a variety of assumptions, model results show that several developing countries could benefit considerably from joining an international emissions trading system, thereby becoming potential collaborators in post-Kyoto climate agreements

  14. EU Emission Trading: Starting with Carbon Dioxide

    DEFF Research Database (Denmark)

    Vesterdal, Morten; Svendsen, Gert Tinggaard

    2003-01-01

    The Commission of the European Union wants to start a limited emission trading scheme by 2005 within the Community to enable "learning-by-doing" prior to the Kyoto Protocol. This to accomplish the desired 8% target level for six different greenhouse gases. However, in the EU it is not clear wheth...

  15. Self-organized global control of carbon emissions

    Science.gov (United States)

    Zhao, Zhenyuan; Fenn, Daniel J.; Hui, Pak Ming; Johnson, Neil F.

    2010-09-01

    There is much disagreement concerning how best to control global carbon emissions. We explore quantitatively how different control schemes affect the collective emission dynamics of a population of emitting entities. We uncover a complex trade-off which arises between average emissions (affecting the global climate), peak pollution levels (affecting citizens’ everyday health), industrial efficiency (affecting the nation’s economy), frequency of institutional intervention (affecting governmental costs), common information (affecting trading behavior) and market volatility (affecting financial stability). Our findings predict that a self-organized free-market approach at the level of a sector, state, country or continent can provide better control than a top-down regulated scheme in terms of market volatility and monthly pollution peaks. The control of volatility also has important implications for any future derivative carbon emissions market.

  16. Carbon Dioxide Emissions: 17 Years and Still Talking

    International Nuclear Information System (INIS)

    This paper, written in French and in English, examines how the figures have changed from Kyoto base year 1990 up to 2007, before looking at certain countries' proposals for the future of their carbon dioxide emissions. Statistics are given concerning the emissions changes in various countries (or groups of countries) but also their developments in regards to the economy and energy use. Changes in CO2 emissions, changes in the gross domestic product of a country, its CO2 emissions per capita, its energy intensity (the ratio of energy use to the monetary value of GDP) and its carbon intensity of energy use as well as population change, are presented. The main countries considered are: United States, European Union, China, Japan, India, Brazil, South Africa and Russia

  17. Forgotten carbon: indirect CO2 in greenhouse gas emission inventories

    International Nuclear Information System (INIS)

    National governments that are Parties to the United Nations Framework Convention on Climate Change (UNFCCC) are required to submit greenhouse gas (GHG) inventories accounting for the emissions and removals occurring within their geographic territories. The Intergovernmental Panel on Climate Change (IPCC) provides inventory methodology guidance to the Parties of the UNFCCC. This methodology guidance, and national inventories based on it, omits carbon dioxide (CO2) from the atmospheric oxidation of methane, carbon monoxide, and non-methane volatile organic compounds emissions that result from several source categories. The inclusion of this category of 'indirect' CO2 in GHG inventories increases global anthropogenic emissions (excluding land use and forestry) between 0.5 and 0.7%. However, the effect of inclusion on aggregate UNFCCC Annex I Party GHG emissions would be to reduce the growth of total emissions, from 1990 to 2004, by 0.2% points. The effect on the GHG emissions and emission trends of individual countries varies. The paper includes a methodology for calculating these emissions and discusses uncertainties. Indirect CO2 is equally relevant for GHG inventories at other scales, such as global, regional, organizational, and facility. Similarly, project-based methodologies, such as those used under the Clean Development Mechanism, may need revising to account for indirect CO2

  18. Evaluating carbon dioxide emissions in international trade of China

    International Nuclear Information System (INIS)

    China is the world's largest emitter of carbon dioxide (CO2). As exports account for about one-third of China's GDP, the CO2 emissions are related to not only China's own consumption but also external demand. Using the input-output analysis (IOA), we analyze the embodied CO2 emissions of China's import and export. Our results show that about 3357 million tons CO2 emissions were embodied in the exports and the emissions avoided by imports (EAI) were 2333 million tons in 2005. The average contribution to embodied emission factors by electricity generation was over 35%. And that by cement production was about 20%. It implies that the production-based emissions of China are more than the consumption-based emissions, which is evidence that carbon leakage occurs under the current climate policies and international trade rules. In addition to the call for a new global framework to allocate emission responsibilities, China should make great efforts to improve its energy efficiency, carry out electricity pricing reforms and increase renewable energy. In particular, to use advanced technology in cement production will be helpful to China's CO2 abatement. (author)

  19. Coping with carbon: a near-term strategy to limit carbon dioxide emissions from power stations.

    Science.gov (United States)

    Breeze, Paul

    2008-11-13

    Burning coal to generate electricity is one of the key sources of atmospheric carbon dioxide emissions; so, targeting coal-fired power plants offers one of the easiest ways of reducing global carbon emissions. Given that the world's largest economies all rely heavily on coal for electricity production, eliminating coal combustion is not an option. Indeed, coal consumption is likely to increase over the next 20-30 years. However, the introduction of more efficient steam cycles will improve the emission performance of these plants over the short term. To achieve a reduction in carbon emissions from coal-fired plant, however, it will be necessary to develop and introduce carbon capture and sequestration technologies. Given adequate investment, these technologies should be capable of commercial development by ca 2020. PMID:18757277

  20. Carbon dioxide emissions from an Acacia plantation on peatland in Sumatra, Indonesia

    Directory of Open Access Journals (Sweden)

    A. Hooijer

    2012-02-01

    Full Text Available Peat surface CO2 emission, groundwater table depth and peat temperature were monitored for two years along transects in an Acacia plantation on thick tropical peat (>4 m in Sumatra, Indonesia. A total of 2300 emission measurements were taken at 144 locations, over a 2 year period. The autotrophic root respiration component of CO2 emission was separated from heterotrophic emission caused by peat oxidation in three ways: (i by comparing CO2 emissions within and beyond the tree rooting zone, (ii by comparing CO2 emissions with and without peat trenching (i.e. cutting any roots remaining in the peat beyond the tree rooting zone, and (iii by comparing CO2 emissions before and after Acacia tree harvesting. On average, the contribution of autotrophic respiration to daytime CO2 emission was 21% along transects in mature tree stands. At locations 0.5 m from trees this was up to 80% of the total emissions, but it was negligible at locations more than 1.3 m away. This means that CO2 emission measurements well away from trees were free of any autotrophic respiration contribution and thus represent only heterotrophic emissions. We found daytime mean annual CO2 emission from peat oxidation alone of 94 t ha−1 y−1 at a mean water table depth of 0.8 m, and a minimum emission value of 80 t ha−1 y−1 after correction for the effect of diurnal temperature fluctuations, which may result in a 14.5% reduction of the daytime emission. There is a positive correlation between mean long-term water table depth and peat oxidation CO2 emission. However, no such relation is found for instantaneous emission/water table depth within transects and it is clear that factors other than water table depth also affect peat oxidation and total CO2 emissions. The increase in the temperature of the surface peat due to plantation establishment may explain over 50% of peat oxidation emissions. Our study sets a standard for greenhouse gas flux studies from tropical peatlands under

  1. Editorial: Using charcoal to fix the price of carbon emissions

    Directory of Open Access Journals (Sweden)

    Nicholas Gray

    2009-12-01

    Full Text Available Using charcoal as a model is probably as close as we can come at present to developing a realistic cost for offsetting CO2 emissions. Of course, carbon taxation needs an equitable basis for calculation and, unlike the current offset costs that are based largely on what the voluntary market can sustain, fixed emission charges per weight may well be the incentive required to achieve elusive GHG reduction targets.

  2. Field emission from non-uniform carbon nanotube arrays

    OpenAIRE

    Dall'Agnol, Fernando F; den Engelsen, Daniel

    2013-01-01

    Regular arrays of carbon nanotubes (CNTs) are frequently used in studies on field emission. However, non-uniformities are always present like dispersions in height, radius, and position. In this report, we describe the effect of these non-uniformities in the overall emission current by simulation. We show that non-uniform arrays can be modeled as a perfect array multiplied by a factor that is a function of the CNTs spacing.

  3. The travel-related carbon dioxide emissions of atmospheric researchers

    OpenAIRE

    A. Stohl

    2008-01-01

    Most atmospheric scientists agree that greenhouse gas emissions have already caused significant changes to the global climate system and that these changes will accelerate in the near future. At the same time, atmospheric scientists who – like other scientists – rely on international collaboration and information exchange travel a lot and, thereby, cause substantial emissions of carbon dioxide (CO2). In this paper, the CO2 emis...

  4. CO2 emission standards and investment in carbon capture

    International Nuclear Information System (INIS)

    Policy makers in a number of countries have proposed or are considering proposing CO2 emission standards for new fossil fuel-fired power plants. The proposed standards require coal-fired power plants to have approximately the same carbon emissions as an uncontrolled natural gas-fired power plant, effectively mandating the adoption of carbon capture and sequestration (CCS) technologies for new coal plants. However, given the uncertainty in the capital and operating costs of a commercial scale coal plant with CCS, the impact of such a standard is not apparent a priori. We apply a stochastic generation expansion model to determine the impact of CO2 emission standards on generation investment decisions, and in particular for coal plants with CCS. Moreover, we demonstrate how the incentive to invest in coal-CCS from emission standards depends on the natural gas price, the CO2 price, and the enhanced oil recovery price, as well as on the level of the emission standard. This analysis is the first to consider the entire power system and at the same time allow the capture percentage for CCS plants to be chosen from a continuous range to meet the given standard at minimum cost. Previous system level studies have assumed that CCS plants capture 90% of the carbon, while studies of individual units have demonstrated the costs of carbon capture over a continuous range. We show that 1) currently proposed levels of emission standards are more likely to shift fossil fuel generation from coal to natural gas rather than to incentivize investment in CCS; 2) tighter standards that require some carbon reductions from natural gas-fired power plants are more likely than proposed standards to incentivize investments in CCS, especially on natural gas plants, but also on coal plants at high gas prices; and 3) imposing a less strict emission standard (emission rates higher than natural gas but lower than coal; e.g., 1500 lbs/MWh) is more likely than current proposals to incentivize investment

  5. World commitment to reduce carbon dioxide emissions

    International Nuclear Information System (INIS)

    A meeting of energy experts in Toronto, sponsored by the Canadian World Energy Council (CANWEC), to examine the implications of sustainable development for the energy industry, is reported. Canada, according to the World Resources Institute, ranks second only to the Arab oil producers as the world's worst energy hog. Although it contributes only 2% of total world greenhouse gases, its per capita emissions rank higher than even the United States, and this despite the fact that over 75% of its electrical energy is produced by hydro and nuclear power. Its intentions to stabilize CO2 emissions by 2000 have already been signalled. Although arguments on the supply side strategies of clean coal and nuclear power were presented at the CANWEC meeting, the accent was firmly on demand side management, through energy conservation and efficiency, to meet the challenge of global warming. (author)

  6. Optimal investment and uncertainty on China's carbon emission abatement

    International Nuclear Information System (INIS)

    To realize environmentally sustainable development of the economy, China has decided to cut carbon dioxide emissions per unit of GDP by 40 to 45 percent by 2020, compared with the level in 2005. Based on China's emission abatement target, this paper first analyzes enterprises' emission reduction pathways in practical production processes, and then develops a framework to derive the magnitude of investment required in each pathway in order to achieve the designated target at the minimal cost. Under the framework, it is found that in the absence of policy guidance, individual enterprises' emission reduction investments deviate from the optimal level. To correct the distortion, an alternative option is provided. Meanwhile, to ensure achievement of the emission reduction target, a stochastic model is introduced to measure the uncertainty arising from emission abatement investment. The results show that an appropriate emission abatement ratio can reduce ‘the systemic risk’ of emission abatement. Finally, a simulation is given to demonstrate the results derived from the stochastic model. - Highlights: ► We formulate enterprises' emission–reduction pathways. ► We examine the cost-minimization problem with emission budget. ► A random model is established to measure the uncertainty of emission abatement. ► Several policy recommendations are proposed.

  7. Synthesis of carbon-14 analogue of 1,5 diaryl-5-[14C]-1,2,3-triazoles

    International Nuclear Information System (INIS)

    Two 1,2,3-triazole anticonvulsants, 1-(4-methylsulfone-phenyl)-5-(4-methyl-phenyl)-1,2,3-triazole and 1-(4-methylsulfone-phenyl)-5-phenyl-1,2,3-triazole, both labeled with carbon-14 in the 5-position were prepared from para-tolunitrile-[cyano-14C] and benzonitrile-[cyano-14C], respectively

  8. Benchmarking carbon emissions performance in supply chains

    OpenAIRE

    Acquaye, Adolf; Genovese, Andrea; Barrett, John W.; Koh, Lenny

    2014-01-01

    Purpose – The paper aims to develop a benchmarking framework to address issues such as supply chain complexity and visibility, geographical differences and non-standardized data, ensuring that the entire supply chain environmental impact (in terms of carbon) and resource use for all tiers, including domestic and import flows, are evaluated. Benchmarking has become an important issue in supply chain management practice. However, challenges such as supply chain complexity and visibility, geogra...

  9. How does temperature affect carbon dioxide emissions?

    Czech Academy of Sciences Publication Activity Database

    Dařenová, Eva; Acosta, Manuel

    Volume 1. 1. Brno: Global Change Research Centre, Academy of Sciences of the Czech Republic, v. v. i, 2015 - (Urban, O.; Klem, K.), s. 130-137 ISBN 978-80-87902-14-1 R&D Projects: GA MŠk(CZ) LO1415 Institutional support: RVO:67179843 Keywords : CO2 assimilation * soil * stem * branches * leaves * respiration Subject RIV: DG - Athmosphere Sciences, Meteorology

  10. Measurements of the Spectral Light Emission from Decaying High Pressure Helium Plasmas

    International Nuclear Information System (INIS)

    The rate of electron density decay has been determined in a helium pulsed discharge plasma at pressures ranging from 100 to 600 Torr, primarily during the early afterglow where the electron density is from 1019 to 2 x 1017/m3. Measurements of the electrical conductivity and the absolute intensity of the light emission were made. The effective recombination rate coefficient was found to increase faster than linearly with gas pressure. The total photon emission rate was significantly lower than the effective recombination rate. Below 400 Torr pressure the afterglow was dominated by He-bands, which were related to the recombination of He2+ and He3+ ions. At higher pressures the appearance of intense lines originating from the atomic n = 3 and 23 P states is proposed to result from the He4+ recombination. Absorption measurements of the atomic metastable concentration gave evidence for recombination directly into the 23 S state. The concentration of molecular metastables was surprisingly low. The light emission had a Teχ dependence, with 0 < χ < 0.35 for the intense atomic lines and 0.78 < χ < 1.10 for the molecular bands

  11. Global carbon dioxide emissions from inland waters

    Science.gov (United States)

    Raymond, Peter A.; Hartmann, Jens; Lauerwald, Ronny; Sobek, Sebastian; McDonald, Cory P.; Hoover, Mark; Butman, David; Striegl, Rob; Mayorga, Emilio; Humborg, Christoph; Kortelainen, Pirkko; Durr, Hans H.; Meybeck, Michel; Ciais, Philippe; Guth, Peter

    2013-01-01

    Carbon dioxide (CO2) transfer from inland waters to the atmosphere, known as CO2 evasion, is a component of the global carbon cycle. Global estimates of CO2 evasion have been hampered, however, by the lack of a framework for estimating the inland water surface area and gas transfer velocity and by the absence of a global CO2 database. Here we report regional variations in global inland water surface area, dissolved CO2 and gas transfer velocity. We obtain global CO2 evasion rates of 1.8   petagrams of carbon (Pg C) per year from streams and rivers and 0.32  Pg C yr−1 from lakes and reservoirs, where the upper and lower limits are respectively the 5th and 95th confidence interval percentiles. The resulting global evasion rate of 2.1 Pg C yr−1 is higher than previous estimates owing to a larger stream and river evasion rate. Our analysis predicts global hotspots in stream and river evasion, with about 70 per cent of the flux occurring over just 20 per cent of the land surface. The source of inland water CO2 is still not known with certainty and new studies are needed to research the mechanisms controlling CO2 evasion globally.

  12. Carbon 14 dating method; Methode de datation par le carbone 14

    Energy Technology Data Exchange (ETDEWEB)

    Fortin, Ph

    2000-07-01

    This document gives a first introduction to {sup 14}C dating as it is put into practice at the radiocarbon dating centre of Claude-Bernard university (Lyon-1 univ., Villeurbanne, France): general considerations and recalls of nuclear physics; the {sup 14}C dating method; the initial standard activity; the isotopic fractioning; the measurement of samples activity; the liquid-scintillation counters; the calibration and correction of {sup 14}C dates; the preparation of samples; the benzene synthesis; the current applications of the method. (J.S.)

  13. Using LMDI approach to analyze changes in carbon dioxide emissions of China’s logistics industry

    OpenAIRE

    Ying Dai; Jing Zhu; Han Song

    2015-01-01

    Purpose: China is confronting with tremendous pressure in carbon emission reduction. While logistics industry seriously relies on fossil fuel, and emits greenhouse gas, especially carbon dioxide. The aim of this article is to estimate the carbon dioxide emission in China’s logistics sector, and analyze the causes for the change of carbon dioxide emission, and identify the critical factors which mainly drive the change in carbon dioxide emissions of China’s logistics industry. Design/methodolo...

  14. Emission Permits Trade of Carbon Based on the Game Theory of Double Auction

    OpenAIRE

    Liu, Na; He, Jixin; Hou, Ning; Gu, Kaiping

    2009-01-01

    As the world's largest carbon resources country with relatively great carbon emission, China in has just started its carbon trade. China is only a passive participant in international carbon trading market, rarely participating in the project of Clean Development Mechanism (CDM). Therefore, trade market of emission permits can be divided into first and second trade markets. During the definition of emission right, we found out that the ways of emission trade at second carbon trade market is t...

  15. Breakdown voltage reduction by field emission in multi-walled carbon nanotubes based ionization gas sensor

    International Nuclear Information System (INIS)

    Ionization gas sensors using vertically aligned multi-wall carbon nanotubes (MWCNT) are demonstrated. The sharp tips of the nanotubes generate large non-uniform electric fields at relatively low applied voltage. The enhancement of the electric field results in field emission of electrons that dominates the breakdown mechanism in gas sensor with gap spacing below 14 μm. More than 90% reduction in breakdown voltage is observed for sensors with MWCNT and 7 μm gap spacing. Transition of breakdown mechanism, dominated by avalanche electrons to field emission electrons, as decreasing gap spacing is also observed and discussed

  16. Breakdown voltage reduction by field emission in multi-walled carbon nanotubes based ionization gas sensor

    Energy Technology Data Exchange (ETDEWEB)

    Saheed, M. Shuaib M.; Muti Mohamed, Norani; Arif Burhanudin, Zainal, E-mail: zainabh@petronas.com.my [Centre of Innovative Nanostructures and Nanodevices, Universiti Teknologi PETRONAS, Bandar Seri Iskandar, 31750 Tronoh, Perak (Malaysia)

    2014-03-24

    Ionization gas sensors using vertically aligned multi-wall carbon nanotubes (MWCNT) are demonstrated. The sharp tips of the nanotubes generate large non-uniform electric fields at relatively low applied voltage. The enhancement of the electric field results in field emission of electrons that dominates the breakdown mechanism in gas sensor with gap spacing below 14 μm. More than 90% reduction in breakdown voltage is observed for sensors with MWCNT and 7 μm gap spacing. Transition of breakdown mechanism, dominated by avalanche electrons to field emission electrons, as decreasing gap spacing is also observed and discussed.

  17. Options for lowering U.S. carbon dioxide emissions

    Science.gov (United States)

    Bierbaum, Rosina M.; Friedman, Robert M.; Levenson, Howard; Rapoport, Richard D.; Sundt, Nick

    1992-03-01

    The United States can decrease its emissions of carbon dioxide (CO2) to as much as 35 percent below 1987 levels within the next 25 years by adopting an aggressive package of policies crossing all sectors of the economy. Such emissions reductions will be difficult to achieve and may be costly, but no major technological breakthroughs are needed. In this paper, we identify a ``Tough'' package of energy conservation, energy supply, and forest managment practices to accomplish this level of emissions reductions. We also present a package of cost-effective, ``Moderate'' technical options, which if adopted, would hold CO2 emissions to about 15-percent increase over 1987 levels by 2015. In constrast, if the United State takes not new actions to curb energy use, CO2 emissions will likely rise 50 percent during that time. A variety of Federal policy initiatives will be required to achieve large reductions in U.S. CO2 emissions. Such policy actions will have to include both regulatory ``push'' and market ``pull'' mechanisms--including performance standards, tax incentive programs, carbon-emission or energy taxes, labeling and efficiency ratings, and research, development, and demostration activities.

  18. Preparation and Infrared Emissivity of Glucose-based Carbon Coated ZnFeO

    OpenAIRE

    ZHOU Jian-Hua,WANG Tao,WANG Dao-Jun,HE Jian-Ping

    2009-01-01

    To restrain the infrared emission of zinc ferrite in 8-14¦˭ wave band, highly dispersed carbon coated ZnFeO nanocomposites were obtained from glucose solution under hydrothermal conditions, where ZnFeO particles prepared firstly in a simple hydrothermal route was used as the seeds. It was proved to be a core-shell structure of glucose-based carbon coated ZnFeO particles by transmission electron microscope (TEM), fourier transform infrared (FT-IR), and UV-Vis technologies. After heat-treated a...

  19. Double-beta decay with majoron emission in GERDA Phase I

    Science.gov (United States)

    Hemmer, Sabine

    2015-07-01

    Neutrinoless double-beta decay with emission of one or two majorons (0 νββχ( χ)) is predicted by several beyond-Standard-Model theories. This article reviews the results of a search for 0 νββχ( χ) of 76Ge using data from the Germanium Detector Array (GERDA) experiment, located underground at the INFN Laboratori Nazionali del Gran Sasso (LNGS) in Italy. The analysis comprised data with an exposure of 20.3 kg·yr from the first phase of the experiment. No indication of contributions to the observed energy spectra was detected for any of the majoron models. The lower limit on the half-life for the ordinary majoron model (spectral index n = 1 was determined to be T {1/2/0 νβ } > 4.2 · 1023 yr (90% quantile). This limit and the limits derived for the other majoron modes constitute the most stringent limits on 0 νββχ( χ) decay of 76Ge measured to date.

  20. Counting efficiency for radionuclides decaying by beta and gamma-ray emission

    International Nuclear Information System (INIS)

    In this paper, counting efficiency vs figure of merit for beta and gamma-ray emitters has been computed. It is assumed that the decay scheme has only a gamma level and the beta-ray emission may be coincident with the gamma-rays or the internal-conversion electrons. The radionuclides tabulated are: 20O, 20F, 28Al, 35P,41Ar, 42K, 47Se, 62Fe, 66Cu, 81Ge, 86Rb, 104Rh, 108Ru, 112Pd, 121Sn(m), 122In, 129I, 141Ce, 142Pr, 151Sm, 170Tm, 171Tm, 194Os, 203Hg, 205Hg, 210Pb, 225Ra, 244Am(m). It has been assumed that the liquid is a toluene based scintillator solution in standard glass vials containing 10 cm3. (Author)

  1. Nuclear energy significantly reduces carbon dioxide emissions

    International Nuclear Information System (INIS)

    This article is devoted to nuclear energy, to its acceptability, compatibility and sustainability. Nuclear energy is non-dispensable part of energy sources with vast innovation potential. The safety of nuclear energy, radioactive waste deposition, and prevention of risk from misuse of nuclear material have to be very seriously adjudged and solved. Nuclear energy is one of the ways how to decrease the contamination of atmosphere with carbon dioxide and it solves partially also the problem of global increase of temperature and climate changes. Given are the main factors responsible for the renaissance of nuclear energy. (author)

  2. A detective from the past called carbon 14

    International Nuclear Information System (INIS)

    The analysis is carried out using Radiometry or Accelerator mass spectrometry. After the system allowing to date the age of any organic rest - whether a fossil, a wood fragment, a parchment or a seed - is an isotope called carbon-14. An atom that comes from reactions nuclear produced in the atmosphere and cosmic-ray-induced they interact with oxygen to form carbon dioxide. This element they absorb it plants in photosynthesis and then passes to the animals remained almost unchanged during the life of the organism. to the meet the initial ratio of c-14 that had been in the atmosphere before his death, the remains that are left in it determine the elapsed time. (Author)

  3. Behaviour of carbon-14 in graphite irradiated by neutrons

    International Nuclear Information System (INIS)

    The method of carbon-14 extraction from graphite irradiated by neutrons based on the thermal effect to graphite in a technological vacuum or air current is a basically new approach. When irradiated graphite is heated in a technological vacuum and in an air current, extraction of carbon-14 takes place and reaches as much as 99.5%. The mass of graphite decreases approximately by 10% in every 5 hours of heating. At the same time, its substance in different units can vary in wide ranges: from 3,5 to 110 kBq/g. This can be explained in terms of both the different substance of nitrogen impurities in graphite and different fluency of thermal neutrons

  4. Progressive extraction method applied to isotopic exchange of carbon-14

    International Nuclear Information System (INIS)

    Isotopic exchange in natural settings is essentially an irreversible process, so that it progresses continuously until there is complete isotopic equilibrium. In soils, this process involves interaction between isotopes in the liquid and solid phases, and complete isotopic equilibrium may take a very long time. Measurements after partial isotopic exchange have been used to characterize the labile fraction of elements in soils. We describe a method to characterize the extent of isotopic exchange, with application here to incorporation of inorganic carbon-14 (14C) into mineral carbonates and organic matter in soils. The procedure uses a continuous addition of extractant, acid, or H2O2in the examples presented here, coupled with sequential sampling. The method has been applied to demonstrate the degree of isotopic exchange in soil. The same strategy could be applied to many other elements, including plant nutrients. (author)

  5. The study of explosive emission from carbon nanotubes

    International Nuclear Information System (INIS)

    The carbon nanotubes (CNT) found applications for high density current electron emitters. The main interest for forming of high current electron beams using CNT is high concentration of electrical field on the nanotubes and high value of yield by electrons for field emission. The experimental results for time processes of forming cathode plasma and extraction of electron beam are presented in the report

  6. UV-induced carbon monoxide emission from living vegetation

    DEFF Research Database (Denmark)

    Bruhn, Dan; Albert, Kristian Rost; Mikkelsen, Teis Nørgaard;

    2013-01-01

    The global burden of carbon monoxide (CO) is rather uncertain. In this paper we address the potential for UV-induced CO emission by living terrestrial vegetation surfaces. Real-time measurements of CO concentrations were made with a cavity enhanced laser spectrometer connected in closed loop to...

  7. Hydrological restoration of Indonesian peatlands to mitigate carbon dioxide emissions

    NARCIS (Netherlands)

    Wösten, H.; Jaenicke, J.; Budiman, A.; Siegert, F.

    2010-01-01

    Delta Session DS 9: The lowland deltas of Indonesia. Hydrological restoration of Indonesian peatlands to mitigate carbon dioxide emissions, Henk Wösten (2010). Presented at the international conference Deltas in Times of Climate Change, 29 September - 1 October, Rotterdam, the Netherlands.

  8. Carbon Emissions Abatement Cost in China: Provincial Panel Data Analysis

    Directory of Open Access Journals (Sweden)

    Jianjun Wang

    2014-05-01

    Full Text Available This paper employs the quadratic directional output distance function to derive shadow prices of China’s aggregate carbon emissions at the province level between 1997 and 2010. The empirical results indicate that the national weighted average shadow price presents an “N-shape” curve across the sample period, experiencing the initial phase of growth followed by a phase of deterioration, and then a further increase. This change trend implies that the cost of carbon emissions reduction is increasing. In addition, the shadow price varies significantly across provinces, which means that China should uphold the principal of “common but differentiated responsibilities” in regional carbon emissions reduction. Generally, the shadow price of the east provinces with high economic development is markedly higher than that of the west provinces with low economic development. The OLS regression results indicate that the shadow price positively connected with the regional economic development levels. Moreover, an inflection point exists in the relation curve between the shadow price and GDP per capita, that is, the increase rate of the shadow price becomes small when the GDP per capita is less than 18.1 thousand Yuan, while it becomes large when the GDP per capita surpasses 18.1 thousand Yuan. With the economic growth, the cost of carbon emissions reduction would be significantly increased. The empirical results can provide more insight for policymakers.

  9. Radiative Neutron Capture on Carbon-14 in Effective Field Theory

    OpenAIRE

    Rupak, Gautam; Fernando, Lakma; Vaghani, Akshay

    2012-01-01

    The cross section for radiative capture of neutron on carbon-14 is calculated using the model-independent formalism of halo effective field theory. The dominant contribution from E1 transition is considered, and the cross section is expressed in terms of elastic scattering parameters of the effective range expansion. Contributions from both resonant and non-resonant interaction are calculated. Significant interference between these leads to a capture contribution that deviates from simple Bre...

  10. Implementation of Emission Trading in Carbon Dioxide Sequestration Optimization Management

    Science.gov (United States)

    Zhang, X.; Duncan, I.

    2013-12-01

    As an effective mid- and long- term solution for large-scale mitigation of industrial CO2 emissions, CO2 capture and sequestration (CCS) has been paid more and more attention in the past decades. A general CCS management system has complex characteristics of multiple emission sources, multiple mitigation technologies, multiple sequestration sites, and multiple project periods. Trade-off exists among numerous environmental, economic, political, and technical factors, leading to varied system features. Sound decision alternatives are thus desired for provide decision supports for decision makers or managers for managing such a CCS system from capture to the final geologic storage phases. Carbon emission trading has been developed as a cost-effective tool for reducing the global greenhouse gas emissions. In this study, a carbon capture and sequestration optimization management model is proposed to address the above issues. The carbon emission trading is integrated into the model, and its impacts on the resulting management decisions are analyzed. A multi-source multi-period case study is provided to justify the applicability of the modeling approach, where uncertainties in modeling parameters are also dealt with.

  11. Carbon tariffs on Chinese exports: Emissions reduction, threat, or farce?

    International Nuclear Information System (INIS)

    (1) We estimate CO2 implicitly exported via commodities relative to a region's total emissions: We find −15% for the industrialized, 12% for the developing region, and 24% for China. (2) We analyze a Contraction and Convergence climate regime in a CGE model including international capital mobility and technology diffusion: When China does not participate in the regime and instead a carbon tariff is imposed on its exports, it will likely be worse off than when participating. This result does not hold for the developing region in general. Meanwhile, the effect on emissions appears small. - Highlights: ► Carbon intensities and contents of trade by commodity and region using GTAP 7. ► Net carbon exports: industrialized region −15%, developing region 12%, China 24%. ► CGE analysis of carbon tariffs based on our carbon intensities. ► The tariffs make China worse off than climate policy and are ambiguous for the developing region. ► They have a small impact on reducing global emissions.

  12. Managing carbon emissions in China through building energy efficiency.

    Science.gov (United States)

    Li, Jun; Colombier, Michel

    2009-06-01

    This paper attempts to analyse the role of building energy efficiency (BEE) in China in addressing climate change mitigation. It provides an analysis of the current situation and future prospects for the adoption of BEE technologies in Chinese cities. It outlines the economic and institutional barriers to large-scale deployment of the sustainable, low-carbon, and even carbon-free construction techniques. Based on a comprehensive overview of energy demand characteristics and development trends driven by economic and demographic growth, different policy tools for cost-effective CO(2) emission reduction in the Chinese construction sector are described. We propose a comprehensive approach combining building design and construction, and the urban planning and building material industries, in order to drastically improve BEE during this period of rapid urban development. A coherent institutional framework needs to be established to ensure the implementation of efficiency policies. Regulatory and incentive options should be integrated into the policy portfolios of BEE to minimise the efficiency gap and to realise sizeable carbon emissions cuts in the next decades. We analyse in detail several policies and instruments, and formulate relevant policy proposals fostering low-carbon construction technology in China. Specifically, Our analysis shows that improving building energy efficiency can generate considerable carbon emissions reduction credits with competitive price under the CDM framework. PMID:19344996

  13. Carbon emissions from forest conversion by Kalimantan oil palm plantations

    Science.gov (United States)

    Carlson, Kimberly M.; Curran, Lisa M.; Asner, Gregory P.; Pittman, Alice Mcdonald; Trigg, Simon N.; Marion Adeney, J.

    2013-03-01

    Oil palm supplies >30% of world vegetable oil production. Plantation expansion is occurring throughout the tropics, predominantly in Indonesia, where forests with heterogeneous carbon stocks undergo high conversion rates. Quantifying oil palm's contribution to global carbon budgets therefore requires refined spatio-temporal assessments of land cover converted to plantations. Here, we report oil palm development across Kalimantan (538,346km2) from 1990 to 2010, and project expansion to 2020 within government-allocated leases. Using Landsat satellite analyses to discern multiple land covers, coupled with above- and below-ground carbon accounting, we develop the first high-resolution carbon flux estimates from Kalimantan plantations. From 1990 to 2010, 90% of lands converted to oil palm were forested (47% intact, 22% logged, 21% agroforests). By 2010, 87% of total oil palm area (31,640km2) occurred on mineral soils, and these plantations contributed 61-73% of 1990-2010 net oil palm emissions (0.020-0.024GtCyr-1). Although oil palm expanded 278% from 2000 to 2010, 79% of allocated leases remained undeveloped. By 2020, full lease development would convert 93,844km2 (~ 90% forested lands, including 41% intact forests). Oil palm would then occupy 34% of lowlands outside protected areas. Plantation expansion in Kalimantan alone is projected to contribute 18-22% (0.12-0.15GtCyr-1) of Indonesia's 2020 CO2-equivalent emissions. Allocated oil palm leases represent a critical yet undocumented source of deforestation and carbon emissions.

  14. Study of Carbon Emission in Computing Scenario

    Directory of Open Access Journals (Sweden)

    Mr. Nikhil B. Dhake Mr. Pankaj M. Poul Prof. Pranav R. Shriram Prof. Kanchan V. Wankhade

    2011-12-01

    Full Text Available This paper presents a case study of what is green computing, why we need to go green computing & will tell you how to minimize the energy consumption as well how to lessen the CO2 emission by going Green Computing. The huge amount of computing manufactured worldwide has a direct impact on environment issues and scientists are conducting numerous studies in order to reduce the negative impact of computing technology on environment. Energy consumption in the datacenter reached the highs. A large corporate IT infrastructure, consumes as much as the energy produced by five power plants over the same time period. This case study will provide a rich source for anyone interested in green computing research.

  15. International mobility in carbon dioxide emissions

    International Nuclear Information System (INIS)

    In this paper, we analyse the evolution of international mobility in per capita CO2 emissions for the period 1971–2007. This concept reveals the distribution's degree of entrenchment which is fundamentally different from other distribution concepts. In particular, we use several different synthetic mobility measures in order to capture the various perceptions of mobility proposed in the literature. This approach can be seen as complementary to the dynamics of distribution approach. The empirical analysis yields the following main results. First, the evolution observed varies according to the mobility index used. Second, when broader mobility indices are used, the most recent years analysed (i.e. 2000–2007) and the 1970s appear to be the most dynamic periods. Third, their decomposition reveals the major role played by the non-high income countries group. Fourth, the calculation of fictitious indices associated with the three major decomposition components of general mobility indicates that exchange (i.e. changes in position) and dispersion (i.e. distribution effects) have typically been the most important mobility factors. Finally, there does not seem to be a clear, convincing relationship between mobility and the evolution of inequality, which to a certain extent underscores the need to carry out a differential analysis for mobility. The results obtained have some implications in terms of analysis and environmental policy. - Highlights: ► The evolution of international mobility in per capita CO2 emissions for the period 1971–2007 is analysed. ► Several different synthetic mobility measures are used for capturing the various perceptions of mobility. ► The mobility is high and, in a significant way, without impact on distribution. ► There does not seem to be a clear, convincing relationship between mobility and the evolution of inequality. ► The results obtained have some implications in terms of analysis and environmental policy

  16. Carbon emission reduction potentials through thinned wood in Japan

    Directory of Open Access Journals (Sweden)

    Ninomiya H

    2011-06-01

    Full Text Available Substituting fossil fuel with woody biomass for bioelectricity production has great potentials for carbon emission reductions while increasing forest productivity to increase carbon sequestration and improve ecological functionalities. Until recently, study on such potentials was very limited. Beginning in 2007, Japan’s special budgets were allocated for a 6-year intensive thinning on about 3.3 million ha of young stands for increasing carbon sinks in Japanese forests to meet the capped amount of 47.7 Tg CO2 year-1 allowed under the Marrakesh Accord. Because of only 30% of the thinned wood were used for sawntimber, CO2 and CH4 must have been emitted from the disposed thinned wood and wood waste. Such emissions and reduction potentials need to be assessed to provide future alternatives for climate change mitigation. We assessed carbon emission reduction potentials when woody biomass from thinned wood is fully utilized for bioelectricity production as compared with the generation of the same amount of energy produced under coal, oil, and natural gas scenarios. Our analytical results show that if all disposed thinned wood and wood waste are utilized to generate energy, about 62.6, 58.3, and 37.8 Tg CO2 year-1 could be prevented from emitting depending on emission scenarios or about 33.2, 30.9, and 20.0% of Japan’s reduction commitment to the Kyoto Protocol. On the other hand, if thinned wood and wood waste are not utilized, about 13.4 Tg CO2 year-1 would be released due to thinning. Our results suggest that incentives to reducing emission reductions in forest sector in the future climate change mitigation agreements will likely lead to large emission reductions, otherwise leakages due to thinning are unavoidable.

  17. A study of legal attributes of carbon emission rights in carbon trading

    Institute of Scientific and Technical Information of China (English)

    Pei Qing; Jiang Dongmei; Zhang Mengheng

    2009-01-01

    Clean Development Mechanism (CDM) has given birth to an international carbon trading market prosperity,which provides developing countries with valuable opportunity to address climate change issues right along with economic development and environmental improvement to achieve sustainable development,However,most studies of CDM focus on economics,and few on its legal problems.CDM involves too many aspects.And the clear legal attribute of trading object is the basis of progress of the transaction and also the start point of legal protection.Therefore,this paper in accordance with the inherent principle of property rights economics,and environmental economics in CDM,only discusses CDM carbon emission right legal interpretation and its attribution.The paper recommends that in order to ensure and promote the carbon emission right trading,carbon emission right should be attributed into the system of real rights to be regulated by Real Right Law.In this way,carbon emission right can gain exclusive power of possession and use,which can achieve a clear right definition of environmental goods in line with Coase's theory to protect Chinese profit in carbon trading market and promote the development of the carbon trading market further.

  18. Measurement of neutrino electron scattering and inverse beta-decay of carbon using neutrinos from stopped muon decay

    International Nuclear Information System (INIS)

    Electron-neutrino electron elastic scattering and two-body electron- neutrino carbon scattering reactions were observed using a 15 ton fine-grained detector and neutrinos from μ+ decay at rest. The data was obtained during an exposure to neutrinos produced in LAMPF proton beam-stop. Based on identification of 262±46 νee- events the total cross-section for νee- → νee- was measured to be σ(νeE-) = (3.09±0.54(stat)±0.39(syst)) x 10-43 cm2. The interference between the weak charged and neutral currents was measured for the first time. The interference was found to be destructive, with a magnitude 0.97±0.22 times the value predicted by the WSG theory. The total cross-section was also used to measure sin2θW = 0.24±0.06(stat)±0.04(syst). The data restricts the maximum allowed value of the neutrino magnetic moment to be less than 1.3 x 10-9 Bohr magnetrons for νe and 8.8 x 10-10 for νmu. In a separate analysis, 182±22 12C(νe,e-) 12N(gs) events with subsequent 12N(β+) 12C were observed, corresponding to a total cross-section, σ(νe12C → e-12N(gs)) = (1.03 ± 0.12(stat) ± 0.10(sys)) x10-41 cm2. This was the first observation of e-induced transitions between specific nuclear states. The results is good agreement with theoretical predictions

  19. Carbon Footprint of Telemedicine Solutions - Unexplored Opportunity for Reducing Carbon Emissions in the Health Sector

    Science.gov (United States)

    Holmner, Åsa; Ebi, Kristie L.; Lazuardi, Lutfan; Nilsson, Maria

    2014-01-01

    Background The healthcare sector is a significant contributor to global carbon emissions, in part due to extensive travelling by patients and health workers. Objectives To evaluate the potential of telemedicine services based on videoconferencing technology to reduce travelling and thus carbon emissions in the healthcare sector. Methods A life cycle inventory was performed to evaluate the carbon reduction potential of telemedicine activities beyond a reduction in travel related emissions. The study included two rehabilitation units at Umeå University Hospital in Sweden. Carbon emissions generated during telemedicine appointments were compared with care-as-usual scenarios. Upper and lower bound emissions scenarios were created based on different teleconferencing solutions and thresholds for when telemedicine becomes favorable were estimated. Sensitivity analyses were performed to pinpoint the most important contributors to emissions for different set-ups and use cases. Results Replacing physical visits with telemedicine appointments resulted in a significant 40–70 times decrease in carbon emissions. Factors such as meeting duration, bandwidth and use rates influence emissions to various extents. According to the lower bound scenario, telemedicine becomes a greener choice at a distance of a few kilometers when the alternative is transport by car. Conclusions Telemedicine is a potent carbon reduction strategy in the health sector. But to contribute significantly to climate change mitigation, a paradigm shift might be required where telemedicine is regarded as an essential component of ordinary health care activities and not only considered to be a service to the few who lack access to care due to geography, isolation or other constraints. PMID:25188322

  20. Measurements of carbon-14 with cavity ring-down spectroscopy

    Science.gov (United States)

    McCartt, A. D.; Ognibene, T.; Bench, G.; Turteltaub, K.

    2015-10-01

    Accelerator Mass Spectrometry (AMS) is the most sensitive method for quantitation of 14C in biological samples. This technology has been used in a variety of low dose, human health related studies over the last 20 years when very high sensitivity was needed. AMS helped pioneer these scientific methods, but its expensive facilities and requirements for highly trained technical staff have limited their proliferation. Quantification of 14C by cavity ring-down spectroscopy (CRDS) offers an approach that eliminates many of the shortcomings of an accelerator-based system and would supplement the use of AMS in biomedical research. Our initial prototype, using a non-ideal wavelength laser and under suboptimal experimental conditions, has a 3.5-modern, 1- σ precision for detection of milligram-sized, carbon-14-elevated samples. These results demonstrate proof of principle and provided a starting point for the development of a spectrometer capable of biologically relevant sensitivities.

  1. Determination of the disintegration rate and gamma emission probabilities per decay of 182 Ta

    International Nuclear Information System (INIS)

    In this work the procedure developed for the standardization of 182Ta sources produced by irradiation at the IPEN IEA-R1 research reactor is presented. The 182Ta decays with a half-life of 114 days by β-emission, populating the excited levels of 182W. It emits gamma rays with several energies mainly between 31 keV and 264 keV and between 1001 keV and 1453 keV. The measurements were performed in a 4πβ-γ coincidence system by using the extrapolation technique. The coincidence system is composed of a 4 π proportional counter coupled to a NaI(Tl) cristal. The measurements were undertaken selecting two windows in the γ-channel, in order to check the consistency of the results. A Monte Carlo calculation was performed in order to predict the behavior of the observed activity as a function of 4πβ the detector efficiency and the results were compared to experimental values. The most intense gamma-ray emission probabilities of 182Ta were determined by means of an HPGe gamma spectrometer, the germanium efficiency curve was obtained by using sources 152Eu, 241Am, 60Co, 133Ba and 166mHo standardized in a primary system. The uncertainties involved in the measurements were treated by the covariance methodology. The results obtained are in good agreement with the experimental uncertainty compared with literature values. (author)

  2. Russian anthropogenic black carbon: Emission reconstruction and Arctic black carbon simulation

    Science.gov (United States)

    Huang, Kan; Fu, Joshua S.; Prikhodko, Vitaly Y.; Storey, John M.; Romanov, Alexander; Hodson, Elke L.; Cresko, Joe; Morozova, Irina; Ignatieva, Yulia; Cabaniss, John

    2015-11-01

    Development of reliable source emission inventories is particularly needed to advance the understanding of the origin of Arctic haze using chemical transport modeling. This study develops a regional anthropogenic black carbon (BC) emission inventory for the Russian Federation, the largest country by land area in the Arctic Council. Activity data from combination of local Russia information and international resources, emission factors based on either Russian documents or adjusted values for local conditions, and other emission source data are used to approximate the BC emissions. Emissions are gridded at a resolution of 0.1° × 0.1° and developed into a monthly temporal profile. Total anthropogenic BC emission of Russia in 2010 is estimated to be around 224 Gg. Gas flaring, a commonly ignored black carbon source, contributes a significant fraction of 36.2% to Russia's total anthropogenic BC emissions. Other sectors, i.e., residential, transportation, industry, and power plants, contribute 25.0%, 20.3%, 13.1%, and 5.4%, respectively. Three major BC hot spot regions are identified: the European part of Russia, the southern central part of Russia where human population densities are relatively high, and the Urals Federal District where Russia's major oil and gas fields are located but with sparse human population. BC simulations are conducted using the hemispheric version of Community Multi-scale Air Quality Model with emission inputs from a global emission database EDGAR (Emissions Database for Global Atmospheric Research)-HTAPv2 (Hemispheric Transport of Air Pollution) and EDGAR-HTAPv2 with its Russian part replaced by the newly developed Russian BC emissions, respectively. The simulation using the new Russian BC emission inventory could improve 30-65% of absorption aerosol optical depth measured at the AERONET sites in Russia throughout the whole year as compared to that using the default HTAPv2 emissions. At the four ground monitoring sites (Zeppelin, Barrow

  3. Cholestyramine-enhanced fecal elimination of carbon-14 in rats after administration of ammonium (/sup 14/C)perfluorooctanoate or potassium (/sup 14/C)perfluorooctanesulfonate

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, J.D.; Gibson, S.J.; Ober, R.E.

    1984-12-01

    After a single intravenous dose of ammonium (/sup 14/C)perfluorooctanoate (( /sup 14/C)PFO, 13.3 mg/kg) or of potassium (/sup 14/C)perfluorooctanesulfonate (( /sup 14/C)PFOS, 3.4 mg/kg) to rats, cholestyramine fed daily as a 4% mixture in feed was shown to increase the total carbon-14 eliminated via feces and to decrease liver concentration of carbon-14. Rats were fed cholestyramine in feed for 14 days after administration of (/sup 14/C)PFO and for 21 days after administration of (/sup 14/C)PFOS. Control rats were administered radiolabeled fluorochemical but were not treated with cholestyramine. Cholestyramine treatment increased mean cumulative carbon-14 elimination in feces by 9.8-fold for rats administered (/sup 14/C)PFO and by 9.5-fold for rats administered (/sup 14/C)PFOS. After (/sup 14/C)PFO, a mean of 4% of the dose of carbon-14 was in liver of cholestyramine-treated rats at 14 days versus 7.6% in control rats; after (/sup 14/C)PFOS, 11.3% of the dose was in liver at 21 days versus 40.3% in control rats. After administration of either radiolabeled compound, plasma and red blood cell carbon-14 concentrations, which were relatively lower than liver concentrations, were also significantly reduced by cholestyramine treatment.

  4. Cholestyramine-enhanced fecal elimination of carbon-14 in rats after administration of ammonium [14C]perfluorooctanoate or potassium [14C]perfluorooctanesulfonate

    International Nuclear Information System (INIS)

    After a single intravenous dose of ammonium [14C]perfluorooctanoate [( 14C]PFO, 13.3 mg/kg) or of potassium [14C]perfluorooctanesulfonate [( 14C]PFOS, 3.4 mg/kg) to rats, cholestyramine fed daily as a 4% mixture in feed was shown to increase the total carbon-14 eliminated via feces and to decrease liver concentration of carbon-14. Rats were fed cholestyramine in feed for 14 days after administration of [14C]PFO and for 21 days after administration of [14C]PFOS. Control rats were administered radiolabeled fluorochemical but were not treated with cholestyramine. Cholestyramine treatment increased mean cumulative carbon-14 elimination in feces by 9.8-fold for rats administered [14C]PFO and by 9.5-fold for rats administered [14C]PFOS. After [14C]PFO, a mean of 4% of the dose of carbon-14 was in liver of cholestyramine-treated rats at 14 days versus 7.6% in control rats; after [14C]PFOS, 11.3% of the dose was in liver at 21 days versus 40.3% in control rats. After administration of either radiolabeled compound, plasma and red blood cell carbon-14 concentrations, which were relatively lower than liver concentrations, were also significantly reduced by cholestyramine treatment

  5. An economic evaluation of carbon emission and carbon sequestration for the forestry sector in Malaysia

    International Nuclear Information System (INIS)

    Forestry is an important sector in Malaysia. The long term development of the forestry sector will definitely affect the future amounts of carbon sequestration and emission of the country. This paper evaluates various forestry economic options that contribute to the reduction of carbon dioxide in the atmosphere. The analysis shows that, although forest plantation could sequester the highest amount of carbon per unit area, natural forests which are managed for sustainable timber production are the cheapest option for per-unit area carbon sequestrated. In evaluating forest options to address the issues of carbon sequestration and emission, the paper proposes that it should be assessed as an integral part of overall long term forestry development of the country which takes into account the future demands for forestry goods and services, financial resources, technology and human resource development. (Author)

  6. Enhanced field emission from nano-graphite coated carbon nanotubes

    Institute of Scientific and Technical Information of China (English)

    LI Qintao; NI Zhichun; GONG Jinlong; ZHU Dezhang; ZHU Zhiyuan

    2007-01-01

    An effective method by low energy carbonhydrogen ion treatment to enhance field emission of the carbon nanotubes (CNTs) is demonstrated. Comparing with control, field emission (FE) currents of the CNTs by carbonhydrogen ion irradiation increased, and the turn-on field and the threshold field decreased significantly. The structure characteristic revealed by transmission electron microscopy demonstrates that CNTs are coated by nano-graphite particles after being treated with low energy carbonhydrogen ion and that there are large quantities of defects and grain boundaries in the coated layer. It is considered that the coating layer can decrease the effective surface work function of CNTs and correspondingly increase field emission. In addition, the defects, the grain boundaries and the C-H dipoles forming in the process of the low energy ions irradiation can effectively enhance the field emission.

  7. Photoelectron spectroscopy of hexachloroplatinate-nucleobase complexes: Nucleobase excited state decay observed via delayed electron emission

    International Nuclear Information System (INIS)

    We report low-temperature photoelectron spectra of isolated gas-phase complexes of the hexachloroplatinate dianion bound to the nucleobases uracil, thymine, cytosine, and adenine. The spectra display well-resolved, distinct peaks that are consistent with complexes where the hexachloroplatinate dianion is largely intact. Adiabatic electron detachment energies for the hexachloroplatinate-nucleobase complexes are measured as 2.26-2.36 eV. The magnitudes of the repulsive Coulomb barriers (RCBs) of the complexes are all ∼1.7 eV, values that are lower than the RCB of the uncomplexed PtCl62− dianion as a result of charge solvation by the nucleobases. In addition to the resolved spectral features, broad featureless bands indicative of delayed electron detachment are observed in the 193 nm photoelectron spectra of the four clusters. The 266 nm spectra of the PtCl62− ⋅ thymine and PtCl62− ⋅ adenine complexes also display very prominent delayed electron emission bands. These results mirror recent results on the related Pt(CN)42− ⋅ nucleobase complexes [A. Sen et al., J. Phys. Chem. B 119, 11626 (2015)]. The observation of delayed electron emission bands in the PtCl62− ⋅ nucleobase spectra obtained in this work, as for the previously studied Pt(CN)42− ⋅ nucleobase complexes, is attributed to one-photon excitation of nucleobase-centred excited states that can effectively couple to the electron detachment continuum, producing strong electron detachment. Moreover, the selective, strong excitation of the delayed emission bands in the 266 nm spectra is linked to fundamental differences in the individual nucleobase photophysics at this excitation energy. This strongly supports our previous suggestion that the dianion within these clusters can be viewed as a “dynamic tag” which has the propensity to emit electrons when the attached nucleobase decays over a time scale long enough to allow autodetachment

  8. Photoelectron Spectroscopy of Hexachloroplatinate-Nucleobase Complexes: Nucleobase Excited State Decay Observed via Delayed Electron Emission

    Energy Technology Data Exchange (ETDEWEB)

    Sen, Ananya; Matthews, Edward M.; Hou, Gao-Lei; Wang, Xue B.; Dessent, Caroline

    2015-11-14

    We report low-temperature photoelectron spectra of isolated gas-phase complexes of the hexachloroplatinate dianion bound to the nucleobases uracil, thymine, cytosine and adenine. The spectra display well-resolved, distinct peaks that are consistent with complexes where the hexachloroplatinate dianion is largely intact. Adiabatic electron detachment energies for the hexachloroplatinate-nucleobase complexes are measured as 2.26-2.36 eV. The magnitudes of the repulsive Coulomb barriers (RCBs) of the complexes are all ~1.7 eV, values that are lower than the RCB of the uncomplexed PtCl6 2- dianion as a result of charge solvation by the nucleobases. In addition to the resolved spectral features, broad featureless bands indicative of delayed electron detachment are observed in the 193 nm photoelectron spectra of the four clusters. The 266 nm spectra of the PtCl6 2-∙thymine and PtCl6 2-∙adenine complexes also display very prominent delayed electron emission bands. These results mirror recent results on the related Pt(CN)4 2-∙nucleobase complexes [Sen et al, J. Phys. Chem. B, 119, 11626, 2015]. The observation of delayed electron emission bands in the PtCl6 2-∙nucleobase spectra obtained in this work, as for the previously studied Pt(CN)4 2-∙nucleobase complexes, is attributed to onephoton excitation of nucleobase-centred excited states that can effectively couple to the electron detachment continuum, producing strong electron detachment. Moreover, the selective, strong excitation of the delayed emission bands in the 266 nm spectra is linked to fundamental differences in the individual nucleobase photophysics at this excitation energy. This strongly supports our previous suggestion that the dianion within these clusters can be viewed as a “dynamic tag” which has the propensity to emit electrons when the attached nucleobase decays over a timescale long enough to allow autodetachment.

  9. Modelling Holocene carbon accumulation and methane emissions of boreal wetlands – an Earth system model approach

    Directory of Open Access Journals (Sweden)

    R. J. Schuldt

    2013-03-01

    Full Text Available Since the Last Glacial Maximum, boreal wetlands have accumulated substantial amounts of peat, estimated at 180–621 Pg of carbon. Wetlands have significantly affected the atmospheric greenhouse gas composition in the past and will play a significant role in future changes of atmospheric CO2 and CH4 concentrations. In order to investigate those changes with an Earth system model, biogeochemical processes in boreal wetlands need to be accounted for. Thus, a model of peat accumulation and decay was developed and included in the land surface model JSBACH of the Max Planck Institute Earth System Model (MPI-ESM. Here we present the evaluation of model results from 6000 yr BP to the pre-industrial period. Over this period of time, 240 Pg of peat carbon accumulated in the model in the areas north of 40° N. Simulated peat accumulation rates agree well with those reported for boreal wetlands. The model simulates CH4 emissions of 49.3 Tg CH4 yr−1 for 6000 yr BP and 51.5 Tg CH4 yr−1 for pre-industrial times. This is within the range of estimates in the literature, which range from 32 to 112 Tg CH4 yr−1 for boreal wetlands. The modelled methane emission for the West Siberian Lowlands and Hudson Bay Lowlands agree well with observations. The rising trend of methane emissions over the last 6000 yr is in agreement with measurements of Antarctic and Greenland ice cores.

  10. Optical emission spectroscopy of carbon arc for nanomaterial synthesis

    Science.gov (United States)

    Vekselman, Vladislav; Stratton, Brentley; Raitses, Yevgeny

    2015-11-01

    Arc plasma assisted synthesis of carbon nanostructures is one of the most efficient and simple production methods. In spite of a long time use of this method in materials science research and industrial applications, the role of the plasma in nucleation and growth of nanostructures is not well understood. This is due to complexity of physico-chemical processes governing the plasma nanosynthesis. The objective of this work is to characterize the atmospheric pressure arc plasma used for synthesis of various carbon nanostructures. Optical emission spectroscopy was carried out to determine the distribution of temperature and density of carbon plasma in the synthesis zone as a function of arc discharge parameters. Accurate and detailed mapping of plasma parameters elucidate the general trend governing the formation of carbon nanostructures. This work was supported by DOE contract DE-AC02-09CH11466.

  11. Exercise based transportation reduces oil consumption and carbon emissions

    Science.gov (United States)

    Higgins, P. A.

    2004-12-01

    Current abuse and misrepresentation of science hinders society's ability to address climate change. Scientific abuse results, in part, from a widespread perception that curbing emissions will require substantial economic, political, or personal sacrifice. Here I provide one example to illustrate that this perception is false. Simply walking or biking the amount recommended for a healthy lifestyle could reduce carbon emissions up to 11 percent if the distances traveled were substituted for car travel. This level of exercise is also sufficient to eliminate obese and overweight conditions in a few years without draconian diet plans. A reduction in carbon dioxide emissions of roughly 35 percent is possible if the revenue saved through decreased health care spending on obesity is redirected toward carbon abatement. This emissions reduction far exceeds that required by the Kyoto Protocol at no net cost. Finally, widespread substitution of driving with distances traveled during recommended daily exercise would considerably ease societal dependence on oil, which leads not only to climate change but also to air pollution, political and economic instability and habitat degradation. Thus, exercise based transportation constitutes a potentially favorable alternative to the energy and diet plans that are currently under consideration and a substantial step toward dealing with the threat of climate change.

  12. A Healthy Reduction in Oil Dependence and Carbon Emissions

    Science.gov (United States)

    Higgins, P. A.; Higgins, M.

    2003-12-01

    Societal dependence on oil as an energy source for personal transportation leads to increasingly negative social consequences including climate change, air pollution, political and economic instability and habitat degradation. Our heavy reliance on the automobile for transportation, determined in part by urban sprawl, also contributes to the population's increasingly sedentary lifestyle and to a concomitant degradation in health. We have shown that widespread substitution of exercise, commensurate with previously recommended levels, through biking or walking instead of driving can substantially reduce oil consumption and carbon emissions. For example, if all individuals between the ages of 10 and 64 substituted one hour of cycling for driving the reduction in gasoline demand would be equivalent to the gas produced from 34.9 percent of current oil consumption. Relative to 1990 net US emissions, this constitutes a 10.9 percent reduction in carbon emissions. Therefore, substitution of exercise for driving could improve health, reduce carbon emissions and save more oil than even upper estimates of that contained in the Arctic National Wildlife Refuge.

  13. Development of TEM and SEM high brightness electron guns using cold-field emission from a carbon nanotip

    International Nuclear Information System (INIS)

    A newly developed carbon cone nanotip (CCnT) has been used as field emission cathode both in low voltage SEM (30 kV) electron source and high voltage TEM (200 kV) electron source. The results clearly show, for both technologies, an unprecedented stability of the emission and the probe current with almost no decay during 1 h, as well as a very small noise (rms less than 0.5%) compared to standard sources which use tungsten tips as emitting cathode. In addition, quantitative electric field mapping around the FE tip have been performed using in situ electron holography experiments during the emission of the new tip. These results show the advantage of the very high aspect ratio of the new CCnT which induces a strong enhancement of the electric field at the apex of the tip, leading to very small extraction voltage (some hundred of volts) for which the field emission will start. The combination of these experiments with emission current measurements has also allowed to extract an exit work function value of 4.8 eV. - Highlights: • We develop a new field emission cathode based on carbon material. • We determine the exit work function of this new cathode using a combination of in situ electron holography and finite element modeling. • We show that the stability of cold-field emitted current can be improved with no decay during one hour of emission with a lower emission noise (less than 0.5%). • We used this cathode both for 200 kV TEM and 30 kV SEM cold field emission source. • As a TEM source, we also observe an increase of the spatial coherence using Fresnel fringes contrast

  14. Development of TEM and SEM high brightness electron guns using cold-field emission from a carbon nanotip

    Energy Technology Data Exchange (ETDEWEB)

    Houdellier, F.; Knoop, L. de; Gatel, C.; Masseboeuf, A. [CEMES-CNRS, 29 Rue Jeanne Marvig, 31055 Toulouse (France); Mamishin, S.; Taniguchi, Y. [Hitachi High-Technologies Corporation, 882, Ichige, Hitachinaka, Ibaraki 312-8504 (Japan); Delmas, M.; Monthioux, M.; Hÿtch, M.J.; Snoeck, E. [CEMES-CNRS, 29 Rue Jeanne Marvig, 31055 Toulouse (France)

    2015-04-15

    A newly developed carbon cone nanotip (CCnT) has been used as field emission cathode both in low voltage SEM (30 kV) electron source and high voltage TEM (200 kV) electron source. The results clearly show, for both technologies, an unprecedented stability of the emission and the probe current with almost no decay during 1 h, as well as a very small noise (rms less than 0.5%) compared to standard sources which use tungsten tips as emitting cathode. In addition, quantitative electric field mapping around the FE tip have been performed using in situ electron holography experiments during the emission of the new tip. These results show the advantage of the very high aspect ratio of the new CCnT which induces a strong enhancement of the electric field at the apex of the tip, leading to very small extraction voltage (some hundred of volts) for which the field emission will start. The combination of these experiments with emission current measurements has also allowed to extract an exit work function value of 4.8 eV. - Highlights: • We develop a new field emission cathode based on carbon material. • We determine the exit work function of this new cathode using a combination of in situ electron holography and finite element modeling. • We show that the stability of cold-field emitted current can be improved with no decay during one hour of emission with a lower emission noise (less than 0.5%). • We used this cathode both for 200 kV TEM and 30 kV SEM cold field emission source. • As a TEM source, we also observe an increase of the spatial coherence using Fresnel fringes contrast.

  15. A detective from the past called carbon 14; Un detective del pasado llamado carbono 14

    Energy Technology Data Exchange (ETDEWEB)

    Trintan, R. M.

    2015-07-01

    The analysis is carried out using Radiometry or Accelerator mass spectrometry. After the system allowing to date the age of any organic rest - whether a fossil, a wood fragment, a parchment or a seed - is an isotope called carbon-14. An atom that comes from reactions nuclear produced in the atmosphere and cosmic-ray-induced they interact with oxygen to form carbon dioxide. This element they absorb it plants in photosynthesis and then passes to the animals remained almost unchanged during the life of the organism. to the meet the initial ratio of c-14 that had been in the atmosphere before his death, the remains that are left in it determine the elapsed time. (Author)

  16. Urban Traffic Congestion Pricing Model with the Consideration of Carbon Emissions Cost

    OpenAIRE

    Jian Wang; Libing Chi; Xiaowei Hu; Hongfei Zhou

    2014-01-01

    As one of the most effective traffic demand management opinions, congestion pricing can reduce private car travel demand and the associated carbon dioxide emissions. First, we summarized the status quo of transport carbon dioxide emission charges and congestion pricing, and then, we analyzed the characteristics of urban transport carbon dioxide emissions. Then, we proposed a (pricing) framework in which carbon emission costs would be considered as part of the generalized cost of travel. Based...

  17. Can carbon emissions from tropical deforestation drop by 50% in 5 years?

    Science.gov (United States)

    Zarin, Daniel J; Harris, Nancy L; Baccini, Alessandro; Aksenov, Dmitry; Hansen, Matthew C; Azevedo-Ramos, Claudia; Azevedo, Tasso; Margono, Belinda A; Alencar, Ane C; Gabris, Chris; Allegretti, Adrienne; Potapov, Peter; Farina, Mary; Walker, Wayne S; Shevade, Varada S; Loboda, Tatiana V; Turubanova, Svetlana; Tyukavina, Alexandra

    2016-04-01

    Halving carbon emissions from tropical deforestation by 2020 could help bring the international community closer to the agreed goal of indigenous peoples' organizations and non-governmental organizations that signed the New York Declaration on Forests (NYDF). We assemble and refine a robust dataset to establish a 2001-2013 benchmark for average annual carbon emissions from gross tropical deforestation at 2.270 Gt CO2 yr(-1). Brazil did not sign the NYDF, yet from 2001 to 2013, Brazil ranks first for both carbon emissions from gross tropical deforestation and reductions in those emissions - its share of the total declined from a peak of 69% in 2003 to a low of 20% in 2012. Indonesia, an NYDF signatory, is the second highest emitter, peaking in 2012 at 0.362 Gt CO2 yr(-1) before declining to 0.205 Gt CO2 yr(-1) in 2013. The other 14 NYDF tropical country signatories were responsible for a combined average of 0.317 Gt CO2 yr(-1) , while the other 86 tropical country non-signatories were responsible for a combined average of 0.688 Gt CO2 yr(-1). We outline two scenarios for achieving the 50% emission reduction target by 2020, both emphasizing the critical role of Brazil and the need to reverse the trends of increasing carbon emissions from gross tropical deforestation in many other tropical countries that, from 2001 to 2013, have largely offset Brazil's reductions. Achieving the target will therefore be challenging, even though it is in the self-interest of the international community. Conserving rather than cutting down tropical forests requires shifting economic development away from a dependence on natural resource depletion toward recognition of the dependence of human societies on the natural capital that tropical forests represent and the goods and services they provide. PMID:26616240

  18. Carbon dioxide and methane emissions from the Yukon River system

    Science.gov (United States)

    Striegl, Rob; Dornblaser, Mark M.; McDonald, Cory P.; Rover, Jennifer R.; Stets, Edward G.

    2012-01-01

    Carbon dioxide (CO2) and methane (CH4) emissions are important, but poorly quantified, components of riverine carbon (C) budgets. This is largely because the data needed for gas flux calculations are sparse and are spatially and temporally variable. Additionally, the importance of C gas emissions relative to lateral C exports is not well known because gaseous and aqueous fluxes are not commonly measured on the same rivers. We couple measurements of aqueous CO2 and CH4 partial pressures (pCO2, pCH4) and flux across the water-air interface with gas transfer models to calculate subbasin distributions of gas flux density. We then combine those flux densities with remote and direct observations of stream and river water surface area and ice duration, to calculate C gas emissions from flowing waters throughout the Yukon River basin. CO2emissions were 7.68 Tg C yr−1 (95% CI: 5.84 −10.46), averaging 750 g C m−2 yr−1 normalized to water surface area, and 9.0 g C m−2 yr−1 normalized to river basin area. River CH4 emissions totaled 55 Gg C yr−1 or 0.7% of the total mass of C emitted as CO2 plus CH4 and ∼6.4% of their combined radiative forcing. When combined with lateral inorganic plus organic C exports to below head of tide, C gas emissions comprised 50% of total C exported by the Yukon River and its tributaries. River CO2 and CH4 derive from multiple sources, including groundwater, surface water runoff, carbonate equilibrium reactions, and benthic and water column microbial processing of organic C. The exact role of each of these processes is not yet quantified in the overall river C budget.

  19. Radioactive decay products in neutron star merger ejecta: heating efficiency and γ-ray emission

    Science.gov (United States)

    Hotokezaka, K.; Wanajo, S.; Tanaka, M.; Bamba, A.; Terada, Y.; Piran, T.

    2016-06-01

    The radioactive decay of the freshly synthesized r-process nuclei ejected in compact binary mergers powers optical/infrared macronovae (kilonovae) that follow these events. The light curves depend critically on the energy partition among the different decay products and it plays an important role in estimates of the amount of ejected r-process elements from a given observed signal. We show that 20-50 per cent of the total radioactive energy is released in γ-rays on time-scales from hours to a month. The number of emitted γ-rays per unit energy interval has roughly a flat spectrum between a few dozen keV and 1 MeV so that most of the energy is carried by ˜1 MeV γ-rays. However, at the peak of macronova emission the optical depth of the γ-rays is ˜0.02 and most of the γ-rays escape. The loss of these γ-rays reduces the heat deposition into the ejecta and hence reduces the expected macronova signals if those are lanthanides dominated. This implies that the ejected mass is larger by a factor of 2-3 than what was previously estimated. Spontaneous fission heats up the ejecta and the heating rate can increase if a sufficient amount of transuranic nuclei are synthesized. Direct measurements of these escaping γ-rays may provide the ultimate proof for the macronova mechanisms and an identification of the r-process nucleosynthesis sites. However, the chances to detect these signals are slim with current X-ray and γ-ray missions. New detectors, more sensitive by at least a factor of 10, are needed for a realistic detection rate.

  20. Carbon and nitrogen additions induce distinct priming effects along an organic-matter decay continuum.

    Science.gov (United States)

    Qiao, Na; Xu, Xingliang; Hu, Yuehua; Blagodatskaya, Evgenia; Liu, Yongwen; Schaefer, Douglas; Kuzyakov, Yakov

    2016-01-01

    Decomposition of organic matter (OM) in soil, affecting carbon (C) cycling and climate feedbacks, depends on microbial activities driven by C and nitrogen (N) availability. However, it remains unknown how decomposition of various OMs vary across global supplies and ratios of C and N inputs. We examined OM decomposition by incubating four types of OM (leaf litter, wood, organic matter from organic and mineral horizons) from a decay continuum in a subtropical forest at Ailao Mountain, China with labile C and N additions. Decomposition of wood with high C:N decreased for 3.9 to 29% with these additions, while leaf decomposition was accelerated only within a narrow C:N range of added C and N. Decomposition of OM from organic horizon was accelerated by high C:N and suppressed by low C:N, but mineral soil was almost entirely controlled by high C:N. These divergent responses to C and N inputs show that mechanisms for priming (i.e. acceleration or retardation of OM decomposition by labile inputs) vary along this decay continuum. We conclude that besides C:N ratios of OM, those of labile inputs control the OM decay in the litter horizons, while energy (labile C) regulates decomposition in mineral soil. This suggests that OM decomposition can be predicted from its intrinsic C:N ratios and those of labile inputs. PMID:26806914

  1. Minimizing emission of carbon dioxide in the coconut processing

    International Nuclear Information System (INIS)

    About 90% of the world's coconut production is made into copra. There are 2-3 million smoke kilns which are used by the coconut farmers for making copra. It is estimated that these kilns emit carbon dioxide from 247 to 366 gram of carbon per kg of copra produced. From the world copra production of 10 M tons, the total carbon released in copra making range is 2-3 Tg(telegram=1012grams) or 2-3M tons of carbon per year. To minimize carbon dioxide emission in copra making, kilns with better combustion characteristics and heat utilization efficiencies must be used. One of the most promising alternative dryers is a direct-fired, natural draft dryer known as the Los Banos (Lozada) Dryer. Developed at the University of the Philippines Los Banos, the dryer consist of a simple burner, a heat distributor and a drying bin. The burner combust coconut shell, corn cob, and wood pieces with extremely high efficiency thus minimizing fuel consumption and dramatically reducing the release of airborne pollutants. The resulting copra is practically smoke free. Tests have shown that carbon dioxide emissions from the Los Banos (Lozada) Dryer are about half of that released by the traditional smoke kilns. Furthermore, the dryer emits lower concentrations of CO (50 ppm vs 2000-3000 ppm), of NOx(5 ppm vs 400 ppm), and SOx(5 ppm vs 400 ppm). When used widely, significant reductions in the emissions of greenhouse and acid rain gases from biomass combustion will be attained. (About 500 units of the Los Banos (Lozada) Dryer are now in use in the Philippines and Papua New Guinea). (Author)

  2. Large carbon and nitrogen pools in subsoil of acid sulphate soils, a potential source for greenhouse gas emissions?

    Czech Academy of Sciences Publication Activity Database

    Virtanen, S.; Šimek, Miloslav; Krištůfek, Václav; Simojoki, A.; Yli-Halla, M.

    2011-01-01

    Roč. 7, č. 3 (2011), s. 227. ISSN 1653-2015. [NJF Congress: Food , Feed, Fuel and Fun /24./, Nordic Feed Science Conference /2./. 14.06.2011-16.06.2011, Uppsala] Institutional research plan: CEZ:AV0Z60660521 Keywords : large carbon and nitrogen pools * acid sulphate soils * greenhouse gas emissions Subject RIV: EH - Ecology, Behaviour

  3. Carbon emissions and management scenarios for consumer-owned utilities

    International Nuclear Information System (INIS)

    An important subset of the utility sector has been scarcely explored for its ability to reduce carbon dioxide emissions: consumer-owned electric utilities significantly contribute to U.S. greenhouse gas emissions, but are often excluded from energy efficiency and renewable energy policies. They sell a quarter of the nation's electricity, yet the carbon impact of these sales is not well understood, due to their small size, unique ownership models, and high percentage of purchased power for distribution. This paper situates consumer-owned utilities in the context of emerging U.S. climate policy, quantifying for the first time the state-by-state carbon impact of electricity sales by consumer-owned utilities. We estimate that total retail sales by consumer-owned utilities account for roughly 568 million metric tons of CO2 annually, making this sector the 7th largest CO2 emitter globally, and examine state-level carbon intensities of the sector in light of the current policy environment and the share of COU distribution in the states. Based on efficiency and fuel mix pathways under conceivable regulations, carbon scenarios for 2030 are developed.

  4. Energy, Carbon-emission and Financial Savings from Thermostat Control

    Energy Technology Data Exchange (ETDEWEB)

    Blasing, T J [ORNL; Schroeder, Dana [University of Georgia, Athens, GA

    2013-08-01

    Among the easiest approaches to energy, and cost, savings for most people is the adjustment of thermostats to save energy. Here we estimate savings of energy, carbon, and money in the United States of America (USA) that would result from adjusting thermostats in residential and commercial buildings by about half a degree Celsius downward during the heating season and upward during the cooling season. To obtain as small a unit as possible, and therefore the least likely to be noticeable by most people, we selected an adjustment of one degree Fahrenheit (0.56 degree Celsius) which is the gradation used almost exclusively on thermostats in the USA and is the smallest unit of temperature that has been used historically. Heating and/or cooling of interior building space for personal comfort is sometimes referred to as space conditioning, a term we will use for convenience throughout this work without consideration of humidity. Thermostat adjustment, as we use the term here, applies to thermostats that control the indoor temperature, and not to other thermostats such as those on water heaters. We track emissions of carbon only, rather than of carbon dioxide, because carbon atoms change atomic partners as they move through the carbon cycle, from atmosphere to biosphere or ocean and, on longer time scales, through the rock cycle. To convert a mass of carbon to an equivalent mass of carbon dioxide (thereby including the mass of the 2 oxygen atoms in each molecule) simply multiply by 3.67.

  5. The social cost of carbon emissions: Seven propositions

    OpenAIRE

    Duncan K. Foley; Rezai, Armon; Taylor, Lance

    2013-01-01

    Determining the social cost of carbon emissions (SCC) is a crucial step in the economic analysis of climate change policy as the US government's recent decision to use a range of estimates of the SCC centered at $77/tC (or, equivalently, $21/tCO2) in cost-benefit analyses of proposed emission-control legislation underlines. This note reviews the welfare economics theory fundamental to the estimation of the SCC in both static and intertemporal contexts, examining the effects of assumptions ...

  6. 76 FR 80368 - Notification of Teleconferences of the Science Advisory Board Biogenic Carbon Emissions Panel

    Science.gov (United States)

    2011-12-23

    ... draft report and accounting framework. As noticed in 76 FR 61100-61101, the SAB Biogenic Carbon... AGENCY Notification of Teleconferences of the Science Advisory Board Biogenic Carbon Emissions Panel... Biogenic Carbon Emissions Panel to review EPA's draft Accounting Framework for Biogenic CO2 Emissions...

  7. Statistical regularities of Carbon emission trading market: Evidence from European Union allowances

    Science.gov (United States)

    Zheng, Zeyu; Xiao, Rui; Shi, Haibo; Li, Guihong; Zhou, Xiaofeng

    2015-05-01

    As an emerging financial market, the trading value of carbon emission trading market has definitely increased. In recent years, the carbon emission allowances have already become a way of investment. They are bought and sold not only by carbon emitters but also by investors. In this paper, we analyzed the price fluctuations of the European Union allowances (EUA) futures in European Climate Exchange (ECX) market from 2007 to 2011. The symmetric and power-law probability density function of return time series was displayed. We found that there are only short-range correlations in price changes (return), while long-range correlations in the absolute of price changes (volatility). Further, detrended fluctuation analysis (DFA) approach was applied with focus on long-range autocorrelations and Hurst exponent. We observed long-range power-law autocorrelations in the volatility that quantify risk, and found that they decay much more slowly than the autocorrelation of return time series. Our analysis also showed that the significant cross correlations exist between return time series of EUA and many other returns. These cross correlations exist in a wide range of fields, including stock markets, energy concerned commodities futures, and financial futures. The significant cross-correlations between energy concerned futures and EUA indicate the physical relationship between carbon emission and energy production process. Additionally, the cross-correlations between financial futures and EUA indicate that the speculation behavior may become an important factor that can affect the price of EUA. Finally we modeled the long-range volatility time series of EUA with a particular version of the GARCH process, and the result also suggests long-range volatility autocorrelations.

  8. Explosive emission cathode on the base of carbon plastic fibre

    International Nuclear Information System (INIS)

    A fabrication process for explosive emission cathodes on the base of carbon plastic fibre of practically any geometrical shape and dimensions is developed. Experimental studies of electron beam current collection from cathodes, 2cm in diameter, at voltages across the diode of 10 and 150-250kV. It is shown that the ignition voltage for cathode plasma is ∼2kV at the interelectrode diode gap of 5mm and residual gas pressure of ∼5x10-5Torr. The carbon-fibre cathode, fabricated in this way, provides more stable current collection of an electron beam (without oscillations) than other cathodes

  9. Simulation and fabrication of carbon nanotubes field emission pressure sensors

    International Nuclear Information System (INIS)

    A novel field emission pressure sensor has been achieved utilizing carbon nanotubes (CNTs) as the electron source. The sensor consists of the anode sensing film fabricated by wet etching process and multi-wall carbon nanotubes (MWNTs) cathode in the micro-vacuum chamber. MWNTs on the silicon substrate were grown by thermal CVD. The prototype pressure sensor has a measured sensitivity of about 0.17-0.77 nA/Pa (101-550 KPa). The work shows the potential use of CNTs-based field-emitter in microsensors, such as accelerometers and tactile sensors

  10. The travel-related carbon dioxide emissions of atmospheric researchers

    Directory of Open Access Journals (Sweden)

    A. Stohl

    2008-04-01

    Full Text Available Most atmospheric scientists agree that greenhouse gas emissions have already caused significant changes to the global climate system and that these changes will accelerate in the near future. At the same time, atmospheric scientists who – like other scientists – rely on international collaboration and information exchange travel a lot and, thereby, cause substantial emissions of carbon dioxide (CO2. In this paper, the CO2 emissions of the employees working at an atmospheric research institute (the Norwegian Institute for Air Research, NILU caused by all types of business travel (conference visits, workshops, field campaigns, instrument maintainance, etc. were calculated for the years 2005–2007. It is estimated that more than 90% of the emissions were caused by air travel, 3% by ground travel and 5% by hotel usage. The travel-related annual emissions were between 1.9 and 2.4 t CO2 per employee or between 3.9 and 5.5 t CO2 per scientist. For comparison, the total annual per capita CO2 emissions are 4.5 t worldwide, 1.2 t for India, 3.8 t for China, 5.9 t for Sweden and 19.1 t for Norway. The travel-related CO2 emissions of a NILU scientist, occurring in 24 days of a year on average, exceed the global average annual per capita emission. Norway's per-capita CO2 emissions are among the highest in the world, mostly because of the emissions from the oil industry. If the emissions per NILU scientist derived in this paper are taken as representative for the average Norwegian researcher, travel by Norwegian scientists would nevertheless account for a substantial 0.2% of Norway's total CO2 emissions. Since most of the travel-related emissions are due to air travel, water vapor emissions, ozone production and contrail formation further increase the relative importance of NILU's travel in terms of radiative forcing.

  11. Potential reduction of carbon emissions from Crude Palm Oil production based on energy and carbon balances

    International Nuclear Information System (INIS)

    Highlights: ► We evaluate energy and carbon equivalence from CPO production based on a CBM. ► Energy spent and produced via carbon movement from palm oil mill was determined. ► Scenarios were formulated to evaluate the potential reduction of carbon emission. ► Utilization of biomass from palm oil mill shows the high potential of C-reduction. -- Abstract: This study aimed to evaluate energy and carbon equivalences (CE) associated with palm oil milling and to evaluate sustainability alternatives for energy consumption. Appropriate ways to reduce carbon emissions were also evaluated. A field survey was carried out to quantify the input and output of energy and materials following the conceptual framework of a carbon-balanced model (CBM), which exclude other non-CO2 greenhouse gases. Survey results indicate that the electrical energy consumption for daily mill start-up averaged 18.7 ± 5.4 kWh/ton Fresh Fruit Bunches (FFBs). This energy is equivalent to 114.4 ± 33.2 kWh/ton Crude Palm Oil (CPO) which was found to be offset by that generated in the mills using palm fiber as a solid fuel. Currently, organic residues contained in the wastewater are anaerobically converted to methane. The methane is used as fuel to generate electricity and sold to an outside grid network at a generation rate of 8.1 ± 2.1 kWh/ton FFB. Based on the CBM approach, carbon emissions observed from the use of fossil energy in palm oil milling were very small; however, total carbon emission from oil palm plantation and palm oil milling were found to be 12.3 kg CE/ton FFB, resulting in the net carbon reduction in CPO production of 2.8 kg CE/ton FFB or 53.7 kg CE/ha-y. Overall, the sum of C-reduction was found 1.2 times greater than that of C-emission. This figure can be increased up to 5.5, if all biomass by-products are used as fuel to generate electricity only. The full potential for carbon reduction from palm oil milling is estimated at 0.94 kW of electric power for every hectare of

  12. Research on the Influence of Carbon Tax on Carbon Emission and Economic Development in China

    Directory of Open Access Journals (Sweden)

    Aihua Luo

    2013-07-01

    Full Text Available Carbon tax is one of ways to cut the emissions of GHG, which has already been employed by the west. To study the effect of carbon tax on energy conservation and carbon reduction in China, a new model is constructed based on dynamic CGE model and the linkage of dynamic CGE model and energy technology model. Besides the improvement of technology of energy, if carbon taxation is employed, the goal to reduce its carbon intensity by 40% by 2020 compared with 2005 need to levy a tax of 60 yuan at least per tonne, the simulations of this tax to carbon reduction, economic and income of residents are analysed under different circumstances, the results shows that there is a great impact on income of residents and GDP with a higher tax burden level.

  13. Carbon Emissions Decomposition and Environmental Mitigation Policy Recommendations for Sustainable Development in Shandong Province

    Directory of Open Access Journals (Sweden)

    Changjian Wang

    2014-11-01

    Full Text Available Provincial carbon emissions research is necessary for China to realize emissions reduction targets. Two-level decomposition model based on the Kaya identity was applied to uncover the main driving forces for the energy related carbon emissions in Shandong province from 1995 to 2011, an important energy base in China. Coal consumption is still the biggest contributor to the increased carbon emissions in Shandong. Decomposition results show that the affluence effect is the most important contributors to the carbon emissions increments. The energy intensity effect is the dominant factor in curbing carbon emissions. The emission coefficient effect plays an important negative but relatively minor effect on carbon emissions. Based on the local realities, a series of environment-friendly mitigation policies are raised by fully considering all of these influencing factors. Sustainable mitigation policies will pay more attention to the low-carbon economic development along with the significant energy intensity reduction in Shangdong province.

  14. The Application of Two-stage Structure Decomposition Technique to the Study of Industrial Carbon Emissions

    Institute of Scientific and Technical Information of China (English)

    Yanqiu HE

    2015-01-01

    The total carbon emissions control is the ultimate goal of carbon emission reduction, while industrial carbon emissions are the basic units of the total carbon emission. On the basis of existing research results, in this paper, a two-stage input-output structure decomposition method is creatively proposed for fully combining the input-output method with the structure decomposition technique. In this study, more comprehensive technical progress indicators were chosen in comparison with the previous studies and included the utilization efficiency of all kinds of intermediate inputs such as energy and non-energy products, and finally were positioned at the factors affecting the carbon emissions of different industries. Through analysis, the affecting rate of each factor on industrial carbon emissions was acquired. Thus, a theory basis and data support is provided for the total carbon emissions control of China from the perspective of industrial emissions.

  15. A Pareto Optimal Auction Mechanism for Carbon Emission Rights

    Directory of Open Access Journals (Sweden)

    Mingxi Wang

    2014-01-01

    Full Text Available The carbon emission rights do not fit well into the framework of existing multi-item auction mechanisms because of their own unique features. This paper proposes a new auction mechanism which converges to a unique Pareto optimal equilibrium in a finite number of periods. In the proposed auction mechanism, the assignment outcome is Pareto efficient and the carbon emission rights’ resources are efficiently used. For commercial application and theoretical completeness, both discrete and continuous markets—represented by discrete and continuous bid prices, respectively—are examined, and the results show the existence of a Pareto optimal equilibrium under the constraint of individual rationality. With no ties, the Pareto optimal equilibrium can be further proven to be unique.

  16. Field Emission Properties of Nitrogen-doped Amorphous Carbon Films

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Nitrogen-doped amorphous carbon thin films are deposited on the ceramic substrates coated with Ti film by using direct current magnetron sputtering technique at N2 and Ar gas mixture atmosphere during deposition. The field emission properties of the deposited films have been investigated. The threshold field as low as 5.93V/μm is obtained and the maximum current density increases from 4μA/cm2 to 20.67μA/cm2 at 10.67V/μm comparing with undoped amorphous film. The results show that nitrogen doping plays an important role in field emission of amorphous carbon thin films.

  17. Carbon market: to which emission quota to devote?

    International Nuclear Information System (INIS)

    As the European Emission Trading Scheme (ETS) is entering its third phase, an article discusses uncertainties and problems regarding this system: CO2 price is falling down, French industrials do not know which quantity they'll have to buy for their installations, and even some frauds and swindles occurred. Besides the fact that the low level of carbon price is not a motivation for investors, the market is criticised for its imbalance between supply and demand. As some industrials find the costs too high, some sectors may consider off-shoring their activities. Some actors suggest the creation of a central bank of carbon. Countries are using the product of emission bidding in different sectors: housing rehabilitation in France, industry support in Germany, reduction of budget deficit in Italy and Great Britain, construction of passive dwellings in Czech Republic

  18. Estimation of Direct Carbon Emissions from Chinese Forest Fires

    Institute of Scientific and Technical Information of China (English)

    TIANXiaorui; GAOChengde; SHULifu; WANGMingyu; YANGXiaohui

    2004-01-01

    Many studies indicated that the products of biosphere burning have short and long-term effects on the atmosphere. Vegetation burning can produce some gases which have significant influence on environment, including some greenhouse gases as CO2 and CH4, etc. Smoke aerosols produced from burning also influence global climate and atmospheric chemistry. The paper calculates the consumed biomass due to forest fires according to the statistics of forest fires from 1991 to 2000 and research results of biomass of Chinese forests. During the study period, forest fires burned average 5Tg-7Tg biomass each year and directly emitted 20.24 Tg-28.56 Tg carbon. In 1991-2000, average emission of carbon dioxide and CH4 account for 2.7%-3.9% and 3.3%-4.7% of the total emission of China (calculating with the data of 2000), respectively.

  19. Radio imaging spectroscopy of synchrotron emission associated with a CME on the 14th of August 2010

    Science.gov (United States)

    Bain, Hazel; Krucker, S.; Saint-Hilaire, P.; Raftery, C.

    2013-07-01

    We present Nancay Radioheliograph observations of a moving type IV solar radio burst which occurred in association with a CME on the 14th of August 2010. The event was well observed at extreme ultraviolet wavelengths by the Atmospheric Imaging Assembly onboard the Solar Dynamics Observatory, the SWAP instrument onboard Proba2 and by the LASCO white light coronograph. The burst emission was found to be cospatial with the core of the CME. Using radio imaging spectroscopy we are able to characterize the underlying electron distribution and plasma parameters within the source. Fitted spectra reveal a clear power law component consistent with optically thin synchrotron emission from accelerated electrons trapped in the erupting flux rope. As is often observed in type IV bursts, polarization measurements show the source to be moderately polarized during the peak of the burst, before steadily increasing to around 70% as the brightness temperature of the burst decays.

  20. Energy-Related Carbon Emissions in Ireland: Scenarios to 2020

    OpenAIRE

    O' Mahony, Tadhg

    2010-01-01

    The consumption of energy and related carbon emissions are a development challenge requiring analysis and policy insights. Current analysis of future change in Ireland relies on quantitative point forecasts within which accuracy is difficult to achieve. A scenario analysis approach has often been applied with the longer term but is also useful on shorter time-scales. This research applied a combination of decomposition analysis and scenario analysis to identify and analyse the driving forces ...

  1. Carbon emissions avoided by electric conservation: the case of lighting

    International Nuclear Information System (INIS)

    Electricity conservation can limit the emissions of carbon dioxide and significantly contribute towards the Kyoto objectives. The detailed prospective modelling of the supply and demand system for electricity in France carried out by INESTENE estimates at 1.86 million tons of equivalent carbon content per year (MtC/y) the sole savings already efficient as regards lighting a value that can rise to 3 MtC/y for the implementation of the technical capacities, i.e. between 10 and 20% of the French effort to respect Kyoto. The use of the supply model ELFIN also highlights the major differences between the economic sectors that request the most electric peak and the other sectors. For example, energy conversation in lights in schools can lead to an emission decrease up to 70% higher than those carried out for a constant base use throughout the year. The study also shows that a method based on a calculation of the average emissions of power plants throughout the year clearly underestimates the gains attributed to energy control. The gains obtained per unit of energy are always higher than 100 gC/kWh, whereas the average carbon content of electricity in France is currently about 20 gC/kWh. Lastly, another significant result of the work concerns the nearly invariable emission gains related to conservation in lighting whether or not there has been a long-term replacement of nuclear energy. These results justify the efforts to control electricity in a 'low electric carbon' country like France. (author)

  2. Memristive model of hysteretic field emission from carbon nanotube arrays

    OpenAIRE

    Gorodetskiy, D. V.; Guselnikov, A. V.; Kanygin, S. N. Shevchenko M. A.; Okotrub, A. V.; Pershin, Y. V.

    2016-01-01

    Some instances of electron field emitters are characterized by frequency-dependent hysteresis in their current-voltage characteristics. We argue that such emitters can be classified as memristive systems and introduce a general framework to describe their response. As a specific example of our approach, we consider field emission from a carbon nanotube array. Our experimental results demonstrate a low-field hysteresis, which is likely caused by an electrostatic alignment of some of the nanotu...

  3. The Search for the CP-violating emission of an E1 photon from the K(L) ---> pi+ pi- gamma decay

    Energy Technology Data Exchange (ETDEWEB)

    Shields, John Michael

    2005-01-01

    A search for the CP-violating electric dipole (E1) direct emission contribution to the K{sub L} {yields} {pi}{sup +}{pi}{sup -}{gamma} decay is performed using data from the 1997 KTeV/E832 experiment. Because the K{sub L} {yields} {pi}{sup +}{pi}{sup -}{gamma} decay mode is massively dominated by the CP-violating inner bremsstrahlung (IB) and the CP-conserving magnetic dipole (M1) direct emission processes, previous analyses have neglected the E1 contribution. Therefore, this measurement is the first attempt to directly quantify the size of the E1 decay process. This E1 transition is one of the very few CP-violating processes that is accessible to experiment and, in principle, will produce new insights into the structure of the neutral kaon. The result of this analysis is that the E1 contribution is below the threshold of sensitivity, and therefore an upper bound of |g{sub E1}| < 0.14 (90% CL) is reported. In the process of obtaining this upper limit, high resolution measurements of fit parameters ({tilde g}{sub M1} and a{sub 1}/a{sub 2}) associated with the size and shape of the M1 direct emission peak are also extracted. The fit results for these parameters: {tilde g}{sub M1} = 1.229 {+-} 0.035 (stat) {+-} 0.087 (syst); a{sub 1}/a{sub 2} = -0.733 {+-} 0.007 (stat) {+-} 0.014 (syst) are in strong agreement with previous measurements.

  4. Field emission from amorphous-carbon nanotips on copper

    International Nuclear Information System (INIS)

    Amorphous-carbon (a-C) nanotips were directly grown on copper substrates by microwave plasma-enhanced chemical-vapor deposition. The length of a typical a-C nanotip is ∼250 nm and its tip diameter is ∼25 nm. The in-plane correlation length La, equivalent to the size of the sp2 clusters, is determined to be 1.2 nm through the intensity ratio of the D and G peaks in the Raman spectrum, which is about in the optimum range for field emission. A low turn-on field of 1.6 V/μm at 10 μA/cm2, a threshold field of 3.8 V/μm at 10 mA/cm2, and a high current density of 32.42 mA/cm2 at 4.0 V/μm are achieved. The field emission characteristics of a-C nanotips are close to those of carbon nanotubes, and much better than what has been reported for flat diamond-like carbon or a-C:H coated cathodes. The roles of the sp2 cluster size, electron confinement and conductivity in the field emission of a-C nanotips are discussed

  5. Determinants of carbon dioxide emissions: Empirical evidence from 69 countries

    Energy Technology Data Exchange (ETDEWEB)

    Sharma, Susan Sunila [School of Accounting, Economics and Finance, Deakin University, 70 Elgar Road, Melbourne, Victoria (Australia)

    2011-01-15

    This study investigates the determinants of carbon dioxide emissions (CO{sub 2}) for a global panel consisting of 69 countries using a dynamic panel data model. To make the panel data analysis more homogenous, we also investigate the determinants of CO{sub 2} emissions for a number of sub-panels. These sub-panels are constructed based on the income level of countries. In this way, we end up with three income panels; namely, high income, middle income, and low income panels. The time component of our dataset is 1985-2005 inclusive. Our main findings are that trade openness, per capita GDP, and energy consumption, proxied by per capita electric power consumption and per capita total primary energy consumption, have positive effects on CO{sub 2} emissions. Urbanisation is found to have a negative impact on CO{sub 2} emissions in high income, middle income, and low income panels. For the global panel, only GDP per capita and per capita total primary energy consumption are found to be statistically significant determinants of CO{sub 2} emission, while urbanisation, trade openness, and per capita electric power consumption have negative effects on the CO{sub 2} emissions. (author)

  6. Calibration of radionuclides with decay trough beta emission or electron capture by liquid scintillation technique

    International Nuclear Information System (INIS)

    In this work is reported a methodology a methodology for pure beta and electron capture radionuclides standardization, suing liquid scintillation technique. In this sense the CIEMAT/NIST method, recently utilized by international laboratories, was implemented and the lack in the Laboratorio Nacional das Radiacoes Ionizantes - LNMRI, of the Comissao Nacional de Energia Nuclear - CNEN, for adequate methodology to standardize this kind if radionuclides was filled, fact that was not present with alpha and gamma radionuclides. The implementation procedure evaluation was provided by concentration activity determination of the following radionuclides: 14 C and 90 Sr, pure beta emitters; 55 Fe, electron capture decay; 204 Tl, electron capture and beta decay and 60 Co, beta-gamma emitter. In this way, a careful analysis of the implementation procedure with these radionuclides types, ranging on a broad energy spectral, was possible. To check the calibration results, intercomparisons among our measurements of these radionuclides and the reference values of the CIEMAT/Spain laboratory were provided. To check the calibration results, intercomparisons among our measurements of these radionuclides and the reference values of the CIEMAT/Spain laboratory were provided. Besides this intercomparisons, one was provided with a 204 Tl solution, utilized in the international comparison recently promoted by BIPM, and another one with a 60 C solution calibrated in LNMRI/CNEN previously by a relative calibration system, with a well type pressurized ionization chamber, and an absolute beta-gamma coincidence system, with a pill-box type proportional counter 4 π geometry, coupled with a scintillator system with a sodium iodide cristal of 4x4 inches. The comparisons among LNMRI/CNEN results and the reference values, showed a small deviation of 1,32% for 14 C, 0,40% for 60 Co, 1,12% for 55 Fe, 0,10% for 90 Sr and 0,73% for 204 Tl. For the BIPM solution the deviation was 0,46% and for 60 Co

  7. Economic Growth And Carbon Emission: A Dynamic Panel Data Analysis

    Directory of Open Access Journals (Sweden)

    Ibrahim BAKIRTAS

    2014-10-01

    Full Text Available The relationship between carbon dioxide emission (CO2 and economic growth is one of the crucial topics in environmental economics. This study is aimed to investigatethat problem. In this study, depending on the theory of Environmental Kuznets Curves (EKC, the impact of income in carbon dioxide emission has measured for 34 OECD and5 BRICS countries with using Dynamic Panel Data Analysis. In this regard OECD countries are classified by income groups due to the average per capita income rate ofOECD to solve the homogeneity problem among OECD countries. On the other hand EKC hypothesis analysed by short and long run income elasticity which will be using foran evident that a country reduces CO2 emissions with the income increase in this study. According to the findings of the study, % 36 of the country sample coherent with theEKC hypothesis. The main encouragement for testing this relationship between economic growth and CO2 emission is leading politicians to reconsider the environmental impactswhich are arising from income increase when they are taking a decision to maximizes the economic growth.Keywords: EKC; OECD; Dynamic Panel Data

  8. Energy security, efficiency and carbon emission of Chinese industry

    International Nuclear Information System (INIS)

    For the Chinese industry as the mainstay of the national economy and dominant energy user and carbon emitter, an integrative assessment is performed from major energy policy perspectives of energy security, energy efficiency and carbon emission. Extensive systems indicators, including oil dependence ratio, average oil growth rate; indices of energy diversity, of carbonization and of oil growth risk; ratios of energy use to output, to value added and to compensation for laborers; ratios of carbon emission to output, to value added and to compensation for laborers, are devised to assess the Chinese industry 2002-2007 with most recent statistics availability. Combined indicators are identified by sparse principle component analysis to characterize sector performances. The industrial sectors are classified into five clusters and the main features of each cluster are pinpointed using fuzzy clustering algorithm. Concrete results facilitate comparisons of sectors to enable more accurate policy recommendations. - Highlights: → An assessment is performed from major energy policy perspectives in China. → Extensive systems indicators are devised to assess the Chinese industry. → Combined indicators are identified by SPCA to characterize sector performance. → Industrial sectors are classified for more accurate policy recommendations.

  9. Determination of 51Cr and 241Am X-ray and gamma-ray emission probabilities per decay

    International Nuclear Information System (INIS)

    Full text: In this paper results of X-ray and gamma-ray emission probabilities per decay of 51Cr and 241Am are presented. The measurements were carried out by means of an HPGe planar spectrometer. The radionuclide 51Cr decays with a half-life of 27.7 days by electron capture process populating the excited levels of 51V, which emits X-rays between 4 and 6 keV and a gamma ray of 320 keV. The radionuclide 241Am decays with a half-life of 157,850 days by alpha emission, populating the excited levels of 237Np, which emits X-rays between 11 and 20 keV and two main gamma rays of 26 and 59 keV. The choice of 51Cr was made due to the need of more results since there are two discrepant sets of values for the 320 keV emission probability per decay in the literature. The choice of 241Am was made because, although this radionuclide be considered a primary standard for spectrometers calibration using its well-known 59 keV gamma ray emission probability, the 26 keV gamma ray and the X-rays emission probabilities present large discrepancies in the literature. The activity of 51Cr and 241Am samples was determined in a 4-coincidence counting system. The same sources were measured in an HPGe planar spectrometer with Be window, suitable for measurements in low energy range. The HPGe spectrometer was calibrated in a well defined geometry by means of 54Mn, 55Fe, 57Co, 133Ba, 152Eu, 166mHo and 241Am (59 keV) sources, previously standardized in a coincidence system. The MCNP Monte Carlo code was used for simulation of the spectrometer calibration curve for the selected geometry, and compared with the experimental one

  10. Using LMDI approach to analyze changes in carbon dioxide emissions of China’s logistics industry

    Directory of Open Access Journals (Sweden)

    Ying Dai

    2015-05-01

    Full Text Available Purpose: China is confronting with tremendous pressure in carbon emission reduction. While logistics industry seriously relies on fossil fuel, and emits greenhouse gas, especially carbon dioxide. The aim of this article is to estimate the carbon dioxide emission in China’s logistics sector, and analyze the causes for the change of carbon dioxide emission, and identify the critical factors which mainly drive the change in carbon dioxide emissions of China’s logistics industry. Design/methodology/approach: The logarithmic mean Divisia index (LMDI method has often been used to analyze decomposition of energy consumption and carbon emission due to its theoretical foundation, adaptability, ease of use and result interpretation. So we use the LMDI method to analyze the changes in carbon dioxide emission in China’s logistics industry in this paper. Findings: By analyzing carbon dioxide emission of China’s logistics, the results show that the carbon dioxide emission of logistics in China has increased by 21.5 times, from 45.1 million tons to 1014.1 million tons in the research period. The highway transport is the main contributor to carbon dioxide emission in logistics industry. The energy intensity and carbon dioxide emission factors were contributing to the reduction of carbon dioxide emission in China’s logistics industry in overall study period. Originality/value: Although there are a lot of literature analyzed carbon dioxide emission in many industry sectors, for example manufacturing, iron and steel , pulp and paper, cement, glass industry, and so on. However, few scholars researched on carbon dioxide emission in logistics industry. This the first study is in the context of carbon dioxide emission of China’s logistics industry.

  11. Measurement of the direct emission and interference terms and search for CP violation in the decay $K\\pm \\to \\pi \\pm \\pi^0 \\gamma$

    CERN Document Server

    Batley, J R; Lazzeroni, C; Munday, D J; Slater, M W; Wotton, S A; Arcidiacono, R; Bocquet, G; Cabibbo, N; Ceccucci, A; Cundy, D; Falaleev, V; Fidecaro, M; Gatignon, L; Gonidec, A; Kubischta, W; Norton, A; Maier, A; Patel, M; Peters, A; Balev, S; Frabetti, P L; Goudzovski, E; Hristov, P; Kekelidze, V; Kozhuharov, V; Litov, L; Madigozhin, D; Marinova, E; Molokanova, N; Polenkevich, I; Potrebenikov, Yu; Stoynev, S; Zinchenko, A; Monnier, E; Swallow, E; Winston, R; Rubin, P; Walker, A; Baldini, W; Cotta Ramusino, A; Dalpiaz, P; Damiani, C; Fiorini, M; Gianoli, A; Martini, M; Petrucci, F; Savrié, M; Scarpa, M; Wahl, H; Bizzeti, A; Lenti, M; Veltri, M; Calvetti, M; Celeghini, E; Iacopini, E; Ruggiero, G; Behler, M; Eppard, K; Kleinknecht, K; Marouelli, P; Masetti, L; Moosbrugger, U; Morales Morales, C; Renk, B; Wache, M; Wanke, R; Winhart, A; Coward, D; Dabrowski, A; Fonseca Martin, T; Shieh, M; Szleper, M; Velasco, M; Wood, M D; Cenci, P; Petrucci, M C; Pepe, M; Anzivino, G; Imbergamo, E; Nappi, A; Piccini, M; Raggi, M; Valdata-Nappi, M; Cerri, C; Fantechi, R; Collazuol, G; DiLella, L; Lamanna, G; Mannelli, i; Michetti, A; Costantini, F; Doble, N; Fiorini, L; Giudici, S; Pierazzini, G; Sozzi, M; Venditti, S; Bloch-Devaux, B; Cheshkov, C; Chèze, J B; De Beer, M; Derré, J; Marel, G; Mazzucato, E; Peyaud, B; Vallage, B; Holder, M; Ziolkowski, M; Bifani, S; Biino, C; Cartiglia, N; Clemencic, M; Goy Lopez, S; Marchetto, F; Dibon, H; Jeitler, M; Markytan, M; Mikulec, I; Neuhofer, G; Widhalm, L

    2010-01-01

    We report on the measurement of the direct emission (DE) and interference (INT) terms of the $K\\pm -> \\pi \\pm \\pi^0 \\gamma$ decay by the NA48/2 experiment at the CERN SPS. From the data collected during 2003 and 2004 about 600k such decay candidates have been selected. The relative amounts of DE and INT with respect to the internal bremsstrahlung (IB) contribution have been measured in the range 014_{sys})x10^{-2} Frac_{INT} (0decays. In addition, a limit on the CP violating asymmetry in the K^+ and K^- branching ratios for this channel has been determined to be less than 1.5x10^{-3} at 90% confidence level.

  12. The ir emission features: Emission from PAH [Polycyclic Aromatic Hydrocarbons] molecules and amorphous carbon particles

    International Nuclear Information System (INIS)

    PAHs can have several forms in the interstellar medium. To assess the importance of each requires the availability of a collection of high quality, complete mid-ir interstellar emission spectra, a collection of laboratory spectra of PAH samples prepared under realistic conditions and a firm understanding of the microscopic emission mechanism. Given what we currently know about PAHs, the spectroscopic data suggests that there are at least two components which contribute to the interstellar emission spectrum: free molecule sized PAHs producing the narrow features and amorphous carbon particles (which are primarily made up of an irregular ''lattice'' of PAHs) contributing to the broad underlying components. An exact treatment of the ir fluorescence from highly vibrationally excited large molecules shows that species containing between 20 and 30 carbon atoms are responsible for the narrow features, although the spectra match more closely with the spectra of amorphous carbon particles. Since little is known about the spectroscopic properties of free PAHs and PAH clusters, much laboratory work is called for in conjunction with an observational program which focuses on the spatial characteristics of the spectra. In this way the distribution and evolution of carbon from molecule to particle can be traced. 38 refs., 9 figs

  13. Climate effects of reducing black carbon emissions: Dependence on location of emission

    Science.gov (United States)

    Fuglestvedt, J.; Berntsen, T.; Myhre, G.; Rive, N. A.; Rypdal, K.; Gerland, S.; Pedersen, C.; Strøm, J.

    2006-12-01

    The role played by emissions of black carbon aerosols (BC) on the Earth's climate is diverse and the overall effect is still quite uncertain: Black carbon not only absorbs sunlight (direct effect), but it also has a semi- direct effect on clouds, and when deposited on snow and ice it changes the reflectivity (albedo) of the ground surface. These mechanisms generally have a warming effect on the climate. This poster presents a Norwegian project that focus on the net effect of current BC emissions and future possible reductions in emissions of BC aerosols, taking into account scientific, economic, and political perspectives on the inclusion of BC in climate policies. Thus, the scope of the project is interdisciplinary and includes observations in the Arctic, model simulations of dispersion of BC aerosols, its radiative forcing and climate effects. Some initial results from measurements of BC content in snow from the Norwegian Arctic and corresponding measurements for surface reflectance will be presented. The radiative forcing of BC emissions from different geographical regions differs due to differences in the removal processes (i.e. the lifetime) and the amount of solar radiation available for absorption (depends on latitude, clouds, and surface albedo). The atmospheric burdens and RF (of the direct effect) of regional BC emissions from fossil fuel sources have been calculated by the global chemical transport model Oslo-CTM2 and a radiative transfer model, and first results of time-integrated RF per unit of emission (equivalent to absolute GWPs) are presented. Future plans including i) analysis of cost effective emission reduction strategies, taking into account regional differences the forcing efficiencies, but also cost estimates for BC reductions in the different regions, and ii) an evaluation of the climate effects of the emission reductions through model simulations, including climatic, economic and political perspectives exploring obstacles and opportunities

  14. Photoelectron spectroscopy of hexachloroplatinate-nucleobase complexes: Nucleobase excited state decay observed via delayed electron emission

    Energy Technology Data Exchange (ETDEWEB)

    Sen, Ananya; Matthews, Edward M.; Dessent, Caroline E. H., E-mail: caroline.dessent@york.ac.uk, E-mail: xuebin.wang@pnnl.gov [Department of Chemistry, University of York, Heslington, York YO10 5DD (United Kingdom); Hou, Gao-Lei; Wang, Xue-Bin, E-mail: caroline.dessent@york.ac.uk, E-mail: xuebin.wang@pnnl.gov [Physical Sciences Division, Pacific Northwest National Laboratory, MS K8-88, P.O. Box 999, Richland, Washington 99352 (United States)

    2015-11-14

    We report low-temperature photoelectron spectra of isolated gas-phase complexes of the hexachloroplatinate dianion bound to the nucleobases uracil, thymine, cytosine, and adenine. The spectra display well-resolved, distinct peaks that are consistent with complexes where the hexachloroplatinate dianion is largely intact. Adiabatic electron detachment energies for the hexachloroplatinate-nucleobase complexes are measured as 2.26-2.36 eV. The magnitudes of the repulsive Coulomb barriers (RCBs) of the complexes are all ∼1.7 eV, values that are lower than the RCB of the uncomplexed PtCl{sub 6}{sup 2−} dianion as a result of charge solvation by the nucleobases. In addition to the resolved spectral features, broad featureless bands indicative of delayed electron detachment are observed in the 193 nm photoelectron spectra of the four clusters. The 266 nm spectra of the PtCl{sub 6}{sup 2−} ⋅ thymine and PtCl{sub 6}{sup 2−} ⋅ adenine complexes also display very prominent delayed electron emission bands. These results mirror recent results on the related Pt(CN){sub 4}{sup 2−} ⋅ nucleobase complexes [A. Sen et al., J. Phys. Chem. B 119, 11626 (2015)]. The observation of delayed electron emission bands in the PtCl{sub 6}{sup 2−} ⋅ nucleobase spectra obtained in this work, as for the previously studied Pt(CN){sub 4}{sup 2−} ⋅ nucleobase complexes, is attributed to one-photon excitation of nucleobase-centred excited states that can effectively couple to the electron detachment continuum, producing strong electron detachment. Moreover, the selective, strong excitation of the delayed emission bands in the 266 nm spectra is linked to fundamental differences in the individual nucleobase photophysics at this excitation energy. This strongly supports our previous suggestion that the dianion within these clusters can be viewed as a “dynamic tag” which has the propensity to emit electrons when the attached nucleobase decays over a time scale long enough to

  15. Half-lives for proton emission, alpha decay, cluster radioactivity, and cold fission processes calculated in a unified theoretical framework

    International Nuclear Information System (INIS)

    Half-life values of spontaneous nuclear decay processes are presented in the framework of the Effective Liquid Drop Model (ELDM) using the combination of varying mass asymmetry shape description for the mass transfer with Werner-Wheeler's inertia coefficient VMAS/WW. The calculated half-lives of ground-state to ground-state transitions for the proton emission, alpha decay, cluster radioactivity, and cold fission processes are compared with experimental data. Results have shown that the ELDM is a very efficient model to describe these different decay processes in a same, unified theoretical framework. A Table listing the predicted half-life values, τc is presented for all possible cases of spontaneous nuclear break-up such that -7.30 10 τc [S] 10(τ/τc) > -17.0, where τ is the total half-life of the parent nucleus. (author)

  16. Stochastic carbon sinks for combating carbon dioxide emissions in the EU

    International Nuclear Information System (INIS)

    This paper carries out numerical calculations on the potential of carbon sinks in the EU Emissions Trading Scheme (ETS) and national commitments under conditions of stochastic carbon dioxide emissions from fossil fuels and carbon sequestration by forests. Chance constraint programming is used to analyze the role of stochastic carbon sinks for national and EU-wide compliance costs. The analytical results show that the inclusion of the carbon sink option can reduce costs for low enough marginal cost and risk discount, but also that costless carbon sinks as by-products from forestry are not part of a cost-effective solution under a high reliability concern. Cost savings are reduced due to risk discounting under a reliability concern, in particular when assigning Chebyshev's inequality as compared with a normal probability distribution. It is also shown that the supply of forest sinks on the market depends on the differences in marginal abatement cost between the trading and the non-trading sectors, and in risk discounting between achievements of the ETS cap and the national commitment. Relatively low marginal abatement cost in the non-trading sector and high risk discounting of national commitment achievements increase the supply of sinks in the market and, hence, reduces the equilibrium price. The empirical application illustrates the importance of risk discounting for the magnitude of cost savings obtained from introducing forest carbon sinks in the EU ETS and national commitments.

  17. Effect of carbon nanotubes upon emissions from cutting and sanding carbon fiber-epoxy composites

    International Nuclear Information System (INIS)

    Carbon nanotubes (CNTs) are being incorporated into structural composites to enhance material strength. During fabrication or repair activities, machining nanocomposites may release CNTs into the workplace air. An experimental study was conducted to evaluate the emissions generated by cutting and sanding on three types of epoxy-composite panels: Panel A containing graphite fibers, Panel B containing graphite fibers and carbon-based mat, and Panel C containing graphite fibers, carbon-based mat, and multi-walled CNTs. Aerosol sampling was conducted with direct-reading instruments, and filter samples were collected for measuring elemental carbon (EC) and fiber concentrations. Our study results showed that cutting Panel C with a band saw did not generate detectable emissions of fibers inspected by transmission electron microscopy but did increase the particle mass, number, and EC emission concentrations by 20–80 % compared to Panels A and B. Sanding operation performed on two Panel C resulted in fiber emission rates of 1.9 × 108 and 2.8 × 106 fibers per second (f/s), while no free aerosol fibers were detected from sanding Panels A and B containing no CNTs. These free CNT fibers may be a health concern. However, the analysis of particle and EC concentrations from these same samples cannot clearly indicate the presence of CNTs, because extraneous aerosol generation from machining the composite epoxy material increased the mass concentrations of the EC

  18. Including carbon emissions from deforestation in the carbon footprint of Brazilian beef.

    Science.gov (United States)

    Cederberg, Christel; Persson, U Martin; Neovius, Kristian; Molander, Sverker; Clift, Roland

    2011-03-01

    Effects of land use changes are starting to be included in estimates of life-cycle greenhouse gas (GHG) emissions, so-called carbon footprints (CFs), from food production. Their omission can lead to serious underestimates, particularly for meat. Here we estimate emissions from the conversion of forest to pasture in the Legal Amazon Region (LAR) of Brazil and present a model to distribute the emissions from deforestation over products and time subsequent to the land use change. Expansion of cattle ranching for beef production is a major cause of deforestation in the LAR. The carbon footprint of beef produced on newly deforested land is estimated at more than 700 kg CO(2)-equivalents per kg carcass weight if direct land use emissions are annualized over 20 years. This is orders of magnitude larger than the figure for beef production on established pasture on non-deforested land. While Brazilian beef exports have originated mainly from areas outside the LAR, i.e. from regions not subject to recent deforestation, we argue that increased production for export has been the key driver of the pasture expansion and deforestation in the LAR during the past decade and this should be reflected in the carbon footprint attributed to beef exports. We conclude that carbon footprint standards must include the more extended effects of land use changes to avoid giving misleading information to policy makers, retailers, and consumers. PMID:21280649

  19. Effect of carbon nanotubes upon emissions from cutting and sanding carbon fiber-epoxy composites

    Energy Technology Data Exchange (ETDEWEB)

    Heitbrink, William A. [LMK OSH Consulting LLC (United States); Lo, Li-Ming, E-mail: LLo@cdc.gov [Centers for Disease Control and Prevention (CDC), Division of Applied Research and Technology, National Institute for Occupational Safety and Health (NIOSH) (United States)

    2015-08-15

    Carbon nanotubes (CNTs) are being incorporated into structural composites to enhance material strength. During fabrication or repair activities, machining nanocomposites may release CNTs into the workplace air. An experimental study was conducted to evaluate the emissions generated by cutting and sanding on three types of epoxy-composite panels: Panel A containing graphite fibers, Panel B containing graphite fibers and carbon-based mat, and Panel C containing graphite fibers, carbon-based mat, and multi-walled CNTs. Aerosol sampling was conducted with direct-reading instruments, and filter samples were collected for measuring elemental carbon (EC) and fiber concentrations. Our study results showed that cutting Panel C with a band saw did not generate detectable emissions of fibers inspected by transmission electron microscopy but did increase the particle mass, number, and EC emission concentrations by 20–80 % compared to Panels A and B. Sanding operation performed on two Panel C resulted in fiber emission rates of 1.9 × 10{sup 8} and 2.8 × 10{sup 6} fibers per second (f/s), while no free aerosol fibers were detected from sanding Panels A and B containing no CNTs. These free CNT fibers may be a health concern. However, the analysis of particle and EC concentrations from these same samples cannot clearly indicate the presence of CNTs, because extraneous aerosol generation from machining the composite epoxy material increased the mass concentrations of the EC.

  20. Carbon nanotube based field emission X-ray sources

    Science.gov (United States)

    Cheng, Yuan

    This dissertation describes the development of field emission (FE) x-ray sources with a carbon-nanotube (CNT) cathode. Field emission x-rays have advantages over conventional x-rays by replacing the thermionic cathode with a cold cathode so that electrons are emitted at room temperature and emission is voltage controllable. CNTs are found to be excellent electron emitters with low threshold fields and high current density which makes them ideal for generate field emission x-rays. Macroscopic CNT cold cathodes are prepared and the parameters to tune their field emission properties are studied: structure and morphology of CNT cathodes, temperature as well as electronic work function of CNT. Macroscopic CNT cathodes with optimized performance are chosen to build a high-resolution x-ray imaging system. The system can readily generate x-ray radiation with continuous variation of temporal resolution up to nanoseconds and spatial resolution down to 10 micron. Its potential applications for dynamic x-ray imaging and micro-computed tomography are also demonstrated. The performance characteristics of this compact and versatile system are promising for non-destructive testing and for non-invasive small-animal imaging for biomedical research.

  1. The impact of financial development on carbon emissions: An empirical analysis in China

    Energy Technology Data Exchange (ETDEWEB)

    Zhang Yuejun, E-mail: zyjmis@126.co [School of Management and Economics, Beijing Institute of Technology, Beijing 100081 (China) and Center for Energy and Environmental Policy Research, Beijing Institute of Technology, Beijing 100081 (China)

    2011-04-15

    Given the complexity between China's financial development and carbon emissions, this paper uses some econometric techniques, including cointegration theory, Granger causality test, variance decomposition, etc., to explore the influence of financial development on carbon emissions. Results indicate that, first, China's financial development acts as an important driver for carbon emissions increase, which should be taken into account when carbon emissions demand is projected. Second, the influence of financial intermediation scale on carbon emissions outweighs that of other financial development indicators but its efficiency's influence appears by far weaker although it may cause the change of carbon emissions statistically. Third, China's stock market scale has relatively larger influence on carbon emissions but the influence of its efficiency is very limited. This to some extent reflects the relatively lower liquidity in China's stock markets. Finally, among financial development indicators, China's FDI exerts the least influence on the change of carbon emissions, due to its relatively smaller volume compared with GDP; but it is mainly utilized in carbon intensive sectors now, therefore, with the increase of China's FDI in the future, many efforts should be made to adapt its utilizing directions and play its positive role in promoting low-carbon development. - Research Highlights: {yields} This paper explores the influence of financial development on carbon emissions. {yields} China's financial development appears to be an important driver for carbon emissions increase. {yields} The influence of financial intermediation scale on carbon emissions outweighs that of other indicators. {yields} China's stock market scale has relatively larger influence on carbon emissions but the influence of its efficiency is very limited. {yields} China's FDI exerts the least influence on carbon emissions change, due to its relatively

  2. The impact of financial development on carbon emissions: An empirical analysis in China

    International Nuclear Information System (INIS)

    Given the complexity between China's financial development and carbon emissions, this paper uses some econometric techniques, including cointegration theory, Granger causality test, variance decomposition, etc., to explore the influence of financial development on carbon emissions. Results indicate that, first, China's financial development acts as an important driver for carbon emissions increase, which should be taken into account when carbon emissions demand is projected. Second, the influence of financial intermediation scale on carbon emissions outweighs that of other financial development indicators but its efficiency's influence appears by far weaker although it may cause the change of carbon emissions statistically. Third, China's stock market scale has relatively larger influence on carbon emissions but the influence of its efficiency is very limited. This to some extent reflects the relatively lower liquidity in China's stock markets. Finally, among financial development indicators, China's FDI exerts the least influence on the change of carbon emissions, due to its relatively smaller volume compared with GDP; but it is mainly utilized in carbon intensive sectors now, therefore, with the increase of China's FDI in the future, many efforts should be made to adapt its utilizing directions and play its positive role in promoting low-carbon development. - Research Highlights: → This paper explores the influence of financial development on carbon emissions. China's financial development appears to be an important driver for carbon emissions increase. → The influence of financial intermediation scale on carbon emissions outweighs that of other indicators. → China's stock market scale has relatively larger influence on carbon emissions but the influence of its efficiency is very limited. → China's FDI exerts the least influence on carbon emissions change, due to its relatively smaller volume compared with China's GDP.

  3. Forest management strategies for reducing carbon emissions, the French case

    Science.gov (United States)

    Valade, Aude; Luyssaert, Sebastiaan; Bellassen, Valentin; Vallet, Patrick; Martin, Manuel

    2015-04-01

    International agreements now recognize the role of forest in the mitigation of climate change through the levers of in-situ sequestration, storage in products and energy and product substitution. These three strategies of carbon management are often antagonistic and it is still not clear which strategy would have the most significant impact on atmospheric carbon concentrations. With a focus on France, this study compares several scenarios of forest management in terms of their effect on the overall carbon budget from trees to wood-products. We elaborated four scenarios of forest management that target different wood production objectives. One scenario is 'Business as usual' and reproduces the current forest management and wood production levels. Two scenarios target an increase in bioenergy wood production, with either long-term or short-term goals. One scenario aims at increasing the production of timber for construction. For this, an empirical regression model was developed building on the rich French inventory database. The model can project the current forest resource at a time horizon of 20 years for characteristic variables diameter, standing volume, above-ground biomass, stand age. A simplified life-cycle analysis provides a full carbon budget for each scenario from forest management to wood use and allows the identification of the scenario that most reduces carbon emissions.

  4. Photovoltaics in the context of carbon emission trading

    International Nuclear Information System (INIS)

    Comprehensive CO2-balances within the life-cycle of PV systems have been carried out considering all CO2 sinks and sources at the locations and under the conditions of production, of transport, installation and operation, as well as of recycling. Calculations of the possible effect on CO2 reduction by PV energy systems may be incorrect if system borders are not set wide enough and remain on a national level. In the examples of Brazil and Germany, the effective CO2 reductions have derived, including the variables of possible interchange scenarios for production and operation of the PV systems, as well as the carbon dioxide intensity of the local electrical grids. In the case of Brazil off-grid applications and the partial substitution of Diesel generating sets by photovoltaics are also examined. CO2 reduction may reach 26,805 kg/kWp for the case of replacement of diesel generators in Brazil by PV based on single crystalline solar cells manufactured in Brazil In the context of carbon dioxide trading, this means a co-financing of 2.3% to 9% by the market values of carbon dioxide value of 5.00 $ US to 20.00 $ US per metric ton. While the carbon value is steadily increasing, carbon emission trading will play an important role in financing autonomous PV systems in the future. (author)

  5. Resolution of heterogeneous fluorescence emission signals and decay lifetime measurement on fluorochrome-labeled cells by phase-sensitive FCM

    Energy Technology Data Exchange (ETDEWEB)

    Steinkamp, J.A.; Crissman, H.A.

    1993-01-01

    A phase-sensitive flow cytometer has been developed to resolve signals from heterogeneous fluorescence emission spectra and quantify fluorescence decay times on cells labeled with fluorescent dyes. This instrument combines flow cytometry (FCM) and fluorescence spectroscopy measurement principles to provide unique capabilities for making phase-resolved measurements on single cells in flow, while preserving conventional FCM measurement capabilities. Stained cells are analyzed as they pass through an intensity-modulated (sinusoid) laser excitation beam. Fluorescence is measured orthogonally using a s barrier filter to block scattered laser excitation light, and a photomultiplier tube detector output signals, which are shifted in phase from a reference signal and amplitude demodulated, are processed by phase-sensitive detection electronics to resolve signals from heterogeneous emissions and quantify decay lifetimes directly. The output signals are displayed as frequency distribution histograms and bivariate diagrams using a computer-based data acquisition system. Results have demonstrated signal phase shift, amplitude demodulation, and average measurement of fluorescence lifetimes on stained cells; a detection limit threshold of 300 to 500 fluorescein isothiocyanate (FITC); fluorescence measurement precision of 1.3% on alignment fluorospheres and 3.4% on propidium iodide (PI)-stained cells; the resolution of PI and FITC signals from cells stainedin combination with PI and FITC, based on differences in their decay lifetimes; and the ability to measure single decay nines by the two-phase, phase comparator, method.

  6. Resolution of heterogeneous fluorescence emission signals and decay lifetime measurement on fluorochrome-labeled cells by phase-sensitive FCM

    Energy Technology Data Exchange (ETDEWEB)

    Steinkamp, J.A.; Crissman, H.A.

    1993-02-01

    A phase-sensitive flow cytometer has been developed to resolve signals from heterogeneous fluorescence emission spectra and quantify fluorescence decay times on cells labeled with fluorescent dyes. This instrument combines flow cytometry (FCM) and fluorescence spectroscopy measurement principles to provide unique capabilities for making phase-resolved measurements on single cells in flow, while preserving conventional FCM measurement capabilities. Stained cells are analyzed as they pass through an intensity-modulated (sinusoid) laser excitation beam. Fluorescence is measured orthogonally using a s barrier filter to block scattered laser excitation light, and a photomultiplier tube detector output signals, which are shifted in phase from a reference signal and amplitude demodulated, are processed by phase-sensitive detection electronics to resolve signals from heterogeneous emissions and quantify decay lifetimes directly. The output signals are displayed as frequency distribution histograms and bivariate diagrams using a computer-based data acquisition system. Results have demonstrated signal phase shift, amplitude demodulation, and average measurement of fluorescence lifetimes on stained cells; a detection limit threshold of 300 to 500 fluorescein isothiocyanate (FITC); fluorescence measurement precision of 1.3% on alignment fluorospheres and 3.4% on propidium iodide (PI)-stained cells; the resolution of PI and FITC signals from cells stainedin combination with PI and FITC, based on differences in their decay lifetimes; and the ability to measure single decay nines by the two-phase, phase comparator, method.

  7. The Concept and Theoretical Implications of Carbon Emissions Rights Based on Individual Equity%The Concept and Theoretical Implications of Carbon Emissions Rights Based on Individual Equity

    Institute of Scientific and Technical Information of China (English)

    Pan Jiahua; Zheng Yan

    2011-01-01

    Climate change has become a hot topic in international environmental negotiations. For post-Kyoto international climate regime negotiations, many countries have proposed a variety of frameworks to share the emission reduction responsibilities and allocate carbon emission rights, and have tried to quantify the emission reduction obligations of all countries based on the perspectives of international equity and individual equity. In this paper, the authors have distinguished the concepts of carbon emissions rights based on these two perspectives respectively, have analyzed the relationship between carbon emissions per capita and economic development, and have calculated and compared the proportion of cumulative emissions per capita of different countries in history and future, and then authors conclude that emission reduction obligations should be allocated based on each country's conditions, including historical emissions, development stage, and future demands. Developed countries should take the initiative to significantly reduce their emissions because they have already accomplished their industrialization process. However, developing countries are still in the process of industrialization, which requires more emission rights to meet their development needs. For China, the concept of carbon emissions based on individual equity can be used as a theoretical tool for the allocating the international carbon emissions rights.

  8. Simulating the integrated summertime d14CO2 signature from anthropogenic emissions over Western Europe

    OpenAIRE

    Bozhinova, D.N.; Molen, van der, H.F.; Velde, Van de, F.; Krol, M. C.; Laan, van der, P.H.; Meijer, H. A. J.; Peters, W.

    2014-01-01

    Radiocarbon dioxide (14CO2, reported in d14CO2) can be used to determine the fossil fuel CO2 addition to the atmosphere, since fossil fuel CO2 no longer contains any 14C. After the release of CO2 at the source, atmospheric transport causes dilution of strong local signals into the background and detectable gradients of d14CO2 only remain in areas with high fossil fuel emissions. This fossil fuel signal can moreover be partially masked by the enriching effect that anthropogenic emissions of 14...

  9. Study on behavior and treatment of radioiodine and carbon-14 at reprocessing of spent fuels

    International Nuclear Information System (INIS)

    Treatment of dissolver Off-gas (DOG) is one of important operation in the head-end process of spent fuel reprocessing. Radioiodine, carbon-14 are contained in the DOG. Confinement of radioiodine is required and the reduction of carbon-14 will be required following ALARA principle. In the present study spent fuel dissolution and off-gas treatment tests were carried out using spent fuel with burnups of 8,000 , 29,000 and 44,000 MWd·t-1. Behavior of radioiodine and carbon-14 was investigated. In addition, several adsorbents for carbon dioxide to capture carbon-14 from the DOG were tested in a cold equipment. (author)

  10. Global Biogenic Emission of Carbon Dioxide from Landfills

    Science.gov (United States)

    Lima, R.; Nolasco, D.; Meneses, W.; Salazar, J.; Hernández, P.; Pérez, N.

    2002-12-01

    Human-induced increases in the atmospheric concentrations of greenhouse gas components have been underway over the past century and are expected to drive climate change in the coming decades. Carbon dioxide was responsible for an estimated 55 % of the antropogenically driven radiactive forcing of the atmosphere in the 1980s and is predicted to have even greater importance over the next century (Houghton et al., 1990). A highly resolved understanding of the sources and sinks of atmospheric CO2, and how they are affected by climate and land use, is essential in the analysis of the global carbon cycle and how it may be impacted by human activities. Landfills are biochemical reactors that produce CH4 and CO2 emissions due to anaerobic digestion of solid urban wastes. Estimated global CH4 emission from landfills is about 44 millions tons per year and account for a 7.4 % of all CH4 sources (Whiticar, 1989). Observed CO2/CH4 molar ratios from landfill gases lie within the range of 0.7-1.0; therefore, an estimated global biogenic emission of CO2 from landfills could reach levels of 11.2-16 millions tons per year. Since biogas extraction systems are installed for extracting, purifying and burning the landfill gases, most of the biogenic gas emission to the atmosphere from landfills occurs through the surface environment in a diffuse and disperse form, also known as non-controlled biogenic emission. Several studies of non-controlled biogenic gas emission from landfills showed that CO2/CH4 weight ratios of surface landfill gases, which are directly injected into the atmosphere, are about 200-300 times higher than those observed in the landfill wells, which are usually collected and burned by gas extraction systems. This difference between surface and well landfill gases is mainly due to bacterial oxidation of the CH4 to CO2 inducing higher CO2/CH4 ratios for surface landfill gases than those well landfill gases. Taking into consideration this observation, the global biogenic

  11. Implications of carbon dust emission for terrestrail carbon cycling and carbon accounting

    Science.gov (United States)

    Wind erosion preferentially removes the finest carbon- and nutrient-rich soil fractions, and consequently its role may be significant within terrestrial carbon (C) cycles. However, the impacts of wind erosion on soil organic carbon (SOC) redistribution are not considered in most carbon cycle models,...

  12. Environmental levels of carbon-14 around a Swedish nuclear power plant measured with accelerator mass spectrometry

    Science.gov (United States)

    Stenström, K.; Erlandsson, B.; Hellborg, R.; Wiebert, A.; Skog, G.

    1996-06-01

    14C is one of the radionuclides which are produced by nuclear power plants. The main part of the 14C, which is released during normal operation, is produced through neutron induced reactions in the cooling water and is released as airborne effluents (such as CO 2 and hydrocarbons) through the ventilation system of the plant to the surrounding environment. Because of the biological importance of carbon and the long half-life of 14C, it is of interest to measure the releases and their incorporation into living material in the environment of the power plants. In this pilot study the accelerator mass spectrometry (AMS) facility at the University of Lund has been used to measure the 14C activity concentration in vegetation around a Swedish nuclear power plant. AMS is suitable mainly because of the accuracy obtained within a short measuring time, which makes it possible to analyze a sufficient number of samples for a thorough investigation. The results of this study demonstrate that the AMS method is suitable for investigations of the influence on the local environment of reactor-released 14C by analysis of living material. To test dispersion models, however, air sampling both of emission source and in the surrounding of the plant seems more suitable.

  13. Theoretical L X-ray emission probabilities in the decay of 241Am

    International Nuclear Information System (INIS)

    L X-rays emitted in the decay of 241Am are widely used for the calibration of X-ray detectors. Many measurements of the X-ray intensities in this decay have been made, however detailed balancing of the decay scheme has not yet been successful. This work attempts balancing of the decay scheme. The balance does not work with published values of fluorescence yields and Coster-Kronig transition probabilities but produces a better balance than previous studies and also shows the possibility of problems due to chemical effects with 241Am as a standard. (orig.)

  14. Effects of endogenous factors on regional land-use carbon emissions based on the Grossman decomposition model: a case study of Zhejiang Province, China.

    Science.gov (United States)

    Wu, Cifang; Li, Guan; Yue, Wenze; Lu, Rucheng; Lu, Zhangwei; You, Heyuan

    2015-02-01

    The impact of land-use change on greenhouse gas emissions has become a core issue in current studies on global change and carbon cycle. However, a comprehensive evaluation of the effects of land-use changes on carbon emissions is very necessary. This paper attempted to apply the Grossman decomposition model to estimate the scale, structural, and management effects of land-use carbon emissions based on final energy consumption by establishing the relationship between the types of land use and carbon emissions in energy consumption. It was shown that land-use carbon emissions increase from 169.5624 million tons in 2000 to 637.0984 million tons in 2010, with an annual average growth rate of 14.15%. Meanwhile, land-use carbon intensity increased from 17.59 t/ha in 2000 to 64.42 t/ha in 2010, with an average annual growth rate of 13.86%. The results indicated that rapid industrialization and urbanization in Zhejiang Province promptly increased urban land and industrial land, which consequently affected land-use extensive emissions. The structural and management effects did not mitigate land-use carbon emissions. By contrast, both factors evidently affected the growth of carbon emissions because of the rigid demands of energy-intensive land-use types and the absence of land management. Results called for the policy implications of optimizing land-use structures and strengthening land-use management. PMID:25421995

  15. An approach to a black carbon emission inventory for Mexico by two methods

    Energy Technology Data Exchange (ETDEWEB)

    Cruz-Núñez, Xochitl, E-mail: xcruz@unam.mx

    2014-05-01

    A black carbon (BC) emission inventory for Mexico is presented. Estimate was performed by using two approaches, based on fuel consumption and emission factors in a top-down scheme, and the second from PM25 emission data and its correlation with black carbon by source category, assuming that black carbon = elemental carbon. Results show that black carbon emissions are in interval 53–473 Gg using the fuel consumption approach and between 62 and 89 using the sector method. Black carbon key sources come from biomass burning in the rural sector, with 47 percent share to the National total. Mobile sources emissions account to 16% to the total. An opportunity to reduce, in the short-term, carbon dioxide equivalent (CO2-eq) emissions by reducing black carbon emissions would be obtained in reducing emissions mainly from biomass burning in rural housing sector and diesel emissions in the transport sector with important co-benefits in direct radiative forcing, public health and air quality. - Highlights: • Black carbon emissions are estimated between 53 and 473 Gg/year on a fuel consumption method. • Black carbon emissions are estimated between 62 and 89 Gg/year on a sector method.

  16. An approach to a black carbon emission inventory for Mexico by two methods

    International Nuclear Information System (INIS)

    A black carbon (BC) emission inventory for Mexico is presented. Estimate was performed by using two approaches, based on fuel consumption and emission factors in a top-down scheme, and the second from PM25 emission data and its correlation with black carbon by source category, assuming that black carbon = elemental carbon. Results show that black carbon emissions are in interval 53–473 Gg using the fuel consumption approach and between 62 and 89 using the sector method. Black carbon key sources come from biomass burning in the rural sector, with 47 percent share to the National total. Mobile sources emissions account to 16% to the total. An opportunity to reduce, in the short-term, carbon dioxide equivalent (CO2-eq) emissions by reducing black carbon emissions would be obtained in reducing emissions mainly from biomass burning in rural housing sector and diesel emissions in the transport sector with important co-benefits in direct radiative forcing, public health and air quality. - Highlights: • Black carbon emissions are estimated between 53 and 473 Gg/year on a fuel consumption method. • Black carbon emissions are estimated between 62 and 89 Gg/year on a sector method

  17. Carbon stocks of intact mangroves and carbon emissions arising from their conversion in the Dominican Republic.

    Science.gov (United States)

    Kauffman, J Boone; Heider, Chris; Norfolk, Jennifer; Payton, Frederick

    2014-04-01

    Mangroves are recognized to possess a variety of ecosystem services including high rates of carbon sequestration and storage. Deforestation and conversion of these ecosystems continue to be high and have been predicted to result in significant carbon emissions to the atmosphere. Yet few studies have quantified the carbon stocks or losses associated with conversion of these ecosystems. In this study we quantified the ecosystem carbon stocks of three common mangrove types of the Caribbean as well as those of abandoned shrimp ponds in areas formerly occupied by mangrove-a common land-use conversion of mangroves throughout the world. In the mangroves of the Montecristi Province in Northwest Dominican Republic we found C stocks ranged from 706 to 1131 Mg/ha. The medium-statured mangroves (3-10 m in height) had the highest C stocks while the tall (> 10 m) mangroves had the lowest ecosystem carbon storage. Carbon stocks of the low mangrove (shrub) type (carbon-rich soils as deep as 2 m. Carbon stocks of abandoned shrimp ponds were 95 Mg/ha or approximately 11% that of the mangroves. Using a stock-change approach, the potential emissions from the conversion of mangroves to shrimp ponds ranged from 2244 to 3799 Mg CO2e/ha (CO2 equivalents). This is among the largest measured C emissions from land use in the tropics. The 6260 ha of mangroves and converted mangroves in the Montecristi Province are estimated to contain 3,841,490 Mg of C. Mangroves represented 76% of this area but currently store 97% of the carbon in this coastal wetland (3,696,722 Mg C). Converted lands store only 4% of the total ecosystem C (144,778 Mg C) while they comprised 24% of the area. By these metrics the replacement of mangroves with shrimp and salt ponds has resulted in estimated emissions from this region totaling 3.8 million Mg CO2e or approximately 21% of the total C prior to conversion. Given the high C stocks of mangroves, the high emissions from their conversion, and the other important

  18. A synthesis of carbon dioxide emissions from fossil-fuel combustion

    DEFF Research Database (Denmark)

    Andres, R.J.; Boden, T.A.; Bréon, F.-M.;

    2012-01-01

    This synthesis discusses the emissions of carbon dioxide from fossil-fuel combustion and cement production. While much is known about these emissions, there is still much that is unknown about the details surrounding these emissions. This synthesis explores our knowledge of these emissions in terms...... which have had emissions reduction as a byproduct of other events, global total emissions continue their general increase with time. Global total fossilfuel carbon dioxide emissions are known to within 10% uncertainty (95% confidence interval). Uncertainty on individual national total fossil-fuel carbon...... dioxide emissions range from a few percent to more than 50 %. This manuscript concludes that carbon dioxide emissions from fossil-fuel combustion continue to increase with time and that while much is known about the overall characteristics of these emissions, much is still to be learned about the detailed...

  19. Potential impact of (CET) carbon emissions trading on China’s power sector: A perspective from different allowance allocation options

    DEFF Research Database (Denmark)

    Cong, Ronggang; Wei, Yi-Ming

    2010-01-01

    In Copenhagen climate conference China government promised that China would cut down carbon intensity 40–45% from 2005 by 2020. CET (carbon emissions trading) is an effective tool to reduce emissions. But because CET is not fully implemented in China up to now, how to design it and its potential...... impact are unknown to us. This paper studies the potential impact of introduction of CET on China’s power sector and discusses the impact of different allocation options of allowances. Agent-based modeling is one appealing new methodology that has the potential to overcome some shortcomings of...... solar power generation in particular develops significantly, with final proportion increasing by 14%. (3) Emission-based allocation brings about both higher electricity and carbon prices than by output-based allocation which encourages producers to be environmentally friendly. Therefore, output...

  20. Taxing Strategies for Carbon Emissions: A Bilevel Optimization Approach

    Directory of Open Access Journals (Sweden)

    Wei Wei

    2014-04-01

    Full Text Available This paper presents a quantitative and computational method to determine the optimal tax rate among generating units. To strike a balance between the reduction of carbon emission and the profit of energy sectors, the proposed bilevel optimization model can be regarded as a Stackelberg game between the government agency and the generation companies. The upper-level, which represents the government agency, aims to limit total carbon emissions within a certain level by setting optimal tax rates among generators according to their emission performances. The lower-level, which represents decision behaviors of the grid operator, tries to minimize the total production cost under the tax rates set by the government. The bilevel optimization model is finally reformulated into a mixed integer linear program (MILP which can be solved by off-the-shelf MILP solvers. Case studies on a 10-unit system as well as a provincial power grid in China demonstrate the validity of the proposed method and its capability in practical applications.

  1. Offsetting China's CO2 Emissions by Soil Carbon Sequestration

    International Nuclear Information System (INIS)

    Fossil fuel emissions of carbon (C) in China in 2000 was about 1 Pg/yr, which may surpass that of the U.S. (1.84 Pg C) by 2020. Terrestrial C pool of China comprises about 35 to 60 Pg in the forest and 120 to 186 Pg in soils. Soil degradation is a major issue affecting 145 Mha by different degradative processes, of which 126 Mha are prone to accelerated soil erosion. Similar to world soils, agricultural soils of China have also lost 30 to 50% or more of the antecedent soil organic carbon (SOC) pool. Some of the depleted SOC pool can be re-sequestered through restoration of degraded soils, and adoption of recommended management practices. The latter include conversion of upland crops to multiple cropping and rice paddies, adoption of integrated nutrient management (INM) strategies, incorporation of cover crops in the rotations cycle and adoption of conservation-effective systems including conservation tillage. A crude estimated potential of soil C sequestration in China is 119 to 226 Tg C/y of SOC and 7 to 138 Tg C/y for soil inorganic carbon (SIC) up to 50 years. The total potential of soil C sequestration is about 12 Pg, and this potential can offset about 25% of the annual fossil fuel emissions in China

  2. The rates of carbon cycling in several soils from AMS14C measurements of fractionated soil organic matter

    International Nuclear Information System (INIS)

    14C mean residence times (MRT) of fractionated organic matter are reported for three pre-bomb soil profiles. Comparisons of organic matter extracted with acid and base showed that the longest MRTs were associated with the non-acid-hydrolysable fraction. The MRT of organic matter in a soil layer represents a combination of the rates of several processes, including decay to CO2 and transport out of the layer. In some instances (notably in the A horizon of the Podzol soil studied in this paper), the MRT is dominated by the rate of transport, rather than the rate of decay. Thus it is important to use the distribution and balance of carbon in the soil profile to assess the meaning of the MRT with respect to influencing atmospheric CO2

  3. The future radiological burden due to carbon 14

    International Nuclear Information System (INIS)

    The global cycling of carbon dioxide from the combustion of fossil fuels and of radiocarbon released from nuclear power facilities has been simulated using a seven-box-model. The model is built up by two boxes for the atmosphere (stratosphere, troposphere), three boxes for the ocean (mixed surface layer, deep sea and sediments), and two boxes for the biosphere (short- and long-lived biota) with non-linear troposphere-biota and troposphere-ocean surface layer exchange rates and linear fluxes between the other reservoirs. The biota growth factor, the exchange of the atmospheric CO2 with the ocean, and the preindustrial atmospheric CO2 content were fitted using the records of the atmospheric CO2 concentration in Mauna Loa, the Suess-effect until 1954, and the response to the C-14 from nuclear weapons tests. The two scenarios considered are (I) annual energy growth rates of 2% and 4%, no nuclear power; (II) a upper and lower estimate of C-14 releases and a best estimate without retention and with a retention factor of four at the fuel reprocessing plants. Assuming logistic source functions for the increase of fossil fuel combustion and an exponentiel growth of nuclear power until the year 2020, the CO2 concentration of the troposphere reaches the 2-5 fold of the preindustrial level around 2100. Simultaneously, the specific C-14 activity of the atmosphere is decreased. The individual lifetime dose commitments (70 y) are found between 0.85 and 0.45 mSv (natural values: 0.73 mSv) and the collective dose commitments until 2100 are about 10% of those due to naturally produced C-14. (orig.)

  4. The test of carbon 14C introducing to sugar beet plant

    International Nuclear Information System (INIS)

    The carbon 14 was introduced to sugar beet plant by photosynthesis. The changes of radioactivity were investigated. It was stated that lower 25 % of carbon 14 stay in leaves, and about 75 % flow to roots in the form of sucrose 14C. (author)

  5. Purifications of calcium carbonate and molybdenum oxide powders for neutrinoless double beta decay experiment, AMoRE

    International Nuclear Information System (INIS)

    The AMoRE (Advanced Mo based Rare process Experiment) collaboration is going to use calcium molybdate crystals to search for neutrinoless double beta decay of 100Mo isotope. In order to make the crystal, we use calcium carbonate and molybdenum oxide powders as raw materials. Therefore it is highly necessary to reduce potential sources for radioactive backgrounds such as U and Th in the powders. In this talk, we will present our studies for purification of calcium carbonate and molybdenum oxide powders

  6. Carbon emission coefficient measurement of the coal-to-power energy chain in China

    OpenAIRE

    Shiwei Yu; Yi-Ming Wei; Haixiang Guo; Liping Ding

    2012-01-01

    Coal-fired electricity generation has become the largest source of carbon emission in China. This study utilizes life-cycle assessment to assess the effect of carbon emissions and to calculate the coefficient of carbon emissions in coal-to-energy chains. Results show that the carbon emission coefficient of the coal-to-energy chain in China is 875 g/kW h-1, which is a relatively low level compared with that of other countries. CO2 is the main type of greenhouse gas emission and the most abunda...

  7. Global Carbon Emissions in the Coming Decades: The Case of China

    Energy Technology Data Exchange (ETDEWEB)

    Levine, Mark; Levine, Mark D.; Aden, Nathaniel T.

    2008-05-01

    China's annual energy-related carbon emissions surpassed those of the United States in In order to build a more robust understanding of China's energy-related carbon emissions, emissions after 2001? The divergence between actual and forecasted carbon emissions international trade, and central government policies in driving emissions growth. so greatly in error and what drove the rapid growth of China's energy-related carbon this article reviews the role of economic restructuring, urbanization, coal dependence, underscores the rapid changes that have taken place in China's energy system since 2001.

  8. Double Auger Emission of fixed-in-space Carbon Monoxide following Core-Excitation and Ionization

    International Nuclear Information System (INIS)

    Double Auger decay after core-level photo excitation and after ionization through synchrotron radiation in gas phase carbon monoxide has been studied. We report the first experiment where both Auger electrons in double Auger decay have been measured in coincidence with the ionic fragments.

  9. Imaging for carbon translocation to a fruit of tomato with carbon-11-labeled carbon dioxide and positron emission tomography

    International Nuclear Information System (INIS)

    Carbon kinetics in the fruit is an agricultural issue on the growth and development of the fruit to be harvested. Particularly, photo-assimilate translocation and distribution are important topics for understanding the mechanism. In the present work, carbon-11 (11C) labeled photo-assimilate translocation into fruits of tomato has been imaged using carbon-11-labeled carbon dioxide and the positron emission tomography (PET). Dynamic PET data of gradual increasing of 11C activity and its distribution is acquired quantitatively in intact plant body. This indicates that the three dimensional photo-assimilate translocation into the fruits is imaged successfully and carbon kinetics is analyzed to understand the plant physiology and nutrition. (authors)

  10. Life cycle carbon emission flow analysis for electricity supply system: A case study of China

    International Nuclear Information System (INIS)

    The carbon emission embodied in trade is fundamental for allocation of responsibility between producers and consumers. This paper quantitatively analyzes embodied carbon emissions along the life cycle of electricity supply, based on network theory. A modified carbon emission flow model is established, based on life cycle assessment considering power losses. There is also a case study of China's interregional electricity supply system in 2010, focusing on two carbon emission carriers, electricity coal transportation and electricity transmission. Results show that the total carbon emission flow reached 169.355 MtCO2eq, i.e., 4.67% of the life cycle carbon emission. Of this, 61.1% was carried by electricity coal transportation before power generation and transmission, owing to an uneven distribution of coal resources. The eastern and southern regions are the major net sinks of carbon emission flows, representing 52.9% and 27.8% of the total, respectively, because of their enormous energy imports. In contrast, the Sanxi region and central China are major net sources of carbon emission flow. The proposed model may help allocate environmental responsibility among different regions, to guarantee balanced trans-regional development. - Highlights: • Hybrid model of LCA and carbon emission flow analysis is established. • Power supply system of China is abstracted as topological network. • Half of the carbon emission flow is carried by fuel transportation system

  11. Carbon dioxide emission prediction using support vector machine

    Science.gov (United States)

    Saleh, Chairul; Rachman Dzakiyullah, Nur; Bayu Nugroho, Jonathan

    2016-02-01

    In this paper, the SVM model was proposed for predict expenditure of carbon (CO2) emission. The energy consumption such as electrical energy and burning coal is input variable that affect directly increasing of CO2 emissions were conducted to built the model. Our objective is to monitor the CO2 emission based on the electrical energy and burning coal used from the production process. The data electrical energy and burning coal used were obtained from Alcohol Industry in order to training and testing the models. It divided by cross-validation technique into 90% of training data and 10% of testing data. To find the optimal parameters of SVM model was used the trial and error approach on the experiment by adjusting C parameters and Epsilon. The result shows that the SVM model has an optimal parameter on C parameters 0.1 and 0 Epsilon. To measure the error of the model by using Root Mean Square Error (RMSE) with error value as 0.004. The smallest error of the model represents more accurately prediction. As a practice, this paper was contributing for an executive manager in making the effective decision for the business operation were monitoring expenditure of CO2 emission.

  12. Carbon dioxide emissions from Specchio di Venere, Pantelleria, Italy

    Science.gov (United States)

    Paz, Mariana P. Jácome; Inguaggiato, Salvatore; Taran, Yuri; Vita, Fabio; Pecoraino, Giovanella

    2016-04-01

    We have mapped the diffuse CO2 efflux from the Specchio di Venere Lake area using the accumulation chamber method. We calculated a CO2 emission of 43 ± 5 t day-1 for the area studied, accounting for both diffuse degassing from soil and bubbling through the lake. We also present data on the water composition of Specchio di Venere Lake, the Polla 3 spring, and Liuzza well. On the basis of water chemistry, two physical-chemical processes, evaporation and mineral precipitation of carbonate species, are invoked to explain the CO2 degassing for the lake area.

  13. Filtration of Carbon Particulate Emissions from a Plasma Pyrolysis Assembly

    Science.gov (United States)

    Agui, Juan H.; Green, Robert; Vijayakumar, R.; Berger, Gordon; Greenwood, Zach; Abney, Morgan; Peterson, Elspeth

    2016-01-01

    NASA is investigating plasma pyrolysis as a candidate technology that will enable the recovery of hydrogen from the methane produced by the ISS Sabatier Reactor. The Plasma Pyrolysis Assembly (PPA) is the current prototype of this technology which converts the methane product from the Carbon Dioxide Reduction Assembly (CRA) to acetylene and hydrogen with 90% or greater conversion efficiency. A small amount of solid carbon particulates are generated as a side product and must be filtered before the acetylene is removed and the hydrogen-rich gas stream is recycled back to the CRA. We discuss developmental work on several options for filtering out the carbon particulate emissions from the PPA exit gas stream. The filtration technologies and concepts investigated range from fibrous media to monolithic ceramic and sintered metal media. This paper describes the different developed filter prototypes and characterizes their performance from integrated testing at the Environmental Chamber (E-Chamber) at MSFC. In addition, characterization data on the generated carbon particulates, that help to define filter requirements, are also presented.

  14. Atomic carbon in comet atmospheres. Origin and emission spectra

    International Nuclear Information System (INIS)

    A detailed study of neutral carbon emissions is made, to precise the excitation mechanism nature, to determine the production mechanisms and examine wether information on CO and CO2 molecule abundance could be deduced, or wether another source must be looked for. After an exhaustive study of excitation rates necessary for theoretical intensity calculation, a new effect has been discovered, and which acts on the atom excitation rates, via their distribution on the fundamental hyperfine levels. On the other hand, the strong dependency of the excitation rate ratio with heliocentric velocity and with the hypothesis which is made on the atom population initial distribution has been revealed. The carbon abundance in all the comets of the initial sample has been calculated, then compared to the water one revealing two groups of comets. Then an abundance criterium to remove the CO and CO2 molecules from the carbon potential-parents in the Bradfield comet has been used while CO is the best candicate for C(3P) and C(1D) atom production in the West, Kohoutek and Bennet comets (but to certain conditions). The important conclusion is that, while the relative abundance (C2/OH, CN/OH,...) of the minor carbon compounds were constant, the CO relative abundance varies from an object to the other, probably an effect due to repeated passage of some comets near the sun

  15. Rapid carbon mineralization for permanent disposal of anthropogenic carbon dioxide emissions

    Science.gov (United States)

    Matter, Juerg M.; Stute, Martin; Snæbjörnsdottir, Sandra Ó.; Oelkers, Eric H.; Gislason, Sigurdur R.; Aradottir, Edda S.; Sigfusson, Bergur; Gunnarsson, Ingvi; Sigurdardottir, Holmfridur; Gunnlaugsson, Einar; Axelsson, Gudni; Alfredsson, Helgi A.; Wolff-Boenisch, Domenik; Mesfin, Kiflom; Taya, Diana Fernandez de la Reguera; Hall, Jennifer; Dideriksen, Knud; Broecker, Wallace S.

    2016-06-01

    Carbon capture and storage (CCS) provides a solution toward decarbonization of the global economy. The success of this solution depends on the ability to safely and permanently store CO2. This study demonstrates for the first time the permanent disposal of CO2 as environmentally benign carbonate minerals in basaltic rocks. We find that over 95% of the CO2 injected into the CarbFix site in Iceland was mineralized to carbonate minerals in less than 2 years. This result contrasts with the common view that the immobilization of CO2 as carbonate minerals within geologic reservoirs takes several hundreds to thousands of years. Our results, therefore, demonstrate that the safe long-term storage of anthropogenic CO2 emissions through mineralization can be far faster than previously postulated.

  16. Rapid carbon mineralization for permanent disposal of anthropogenic carbon dioxide emissions.

    Science.gov (United States)

    Matter, Juerg M; Stute, Martin; Snæbjörnsdottir, Sandra Ó; Oelkers, Eric H; Gislason, Sigurdur R; Aradottir, Edda S; Sigfusson, Bergur; Gunnarsson, Ingvi; Sigurdardottir, Holmfridur; Gunnlaugsson, Einar; Axelsson, Gudni; Alfredsson, Helgi A; Wolff-Boenisch, Domenik; Mesfin, Kiflom; Taya, Diana Fernandez de la Reguera; Hall, Jennifer; Dideriksen, Knud; Broecker, Wallace S

    2016-06-10

    Carbon capture and storage (CCS) provides a solution toward decarbonization of the global economy. The success of this solution depends on the ability to safely and permanently store CO2 This study demonstrates for the first time the permanent disposal of CO2 as environmentally benign carbonate minerals in basaltic rocks. We find that over 95% of the CO2 injected into the CarbFix site in Iceland was mineralized to carbonate minerals in less than 2 years. This result contrasts with the common view that the immobilization of CO2 as carbonate minerals within geologic reservoirs takes several hundreds to thousands of years. Our results, therefore, demonstrate that the safe long-term storage of anthropogenic CO2 emissions through mineralization can be far faster than previously postulated. PMID:27284192

  17. The application of the acoustic emission technique to stone decay by sodium sulphate in laboratory tests

    Directory of Open Access Journals (Sweden)

    Grossi, C. M.

    1997-03-01

    Full Text Available Acoustic emission was monitored during salt crystallisation cycles in order to study the mechanisms of rock deterioration by sodium sulphate in laboratory tests. Some porous carbonate stones used in Spanish monuments (Cathedral of Oviedo, Murcia and Seo Vella of Lérida were selected for this study. The acoustic emission detected during the different stages of the cycles (immersion, drying and cooling was interpreted to be the result of the salt behaviour inside the stone. The use of this technique has confirmed that this behaviour depends on salt characteristics (solubility, hydration state and polymorphism of anhydrous sodium sulphate and stone porosity and pore network.

    Para determinar los mecanismos de deterioro de las rocas debidos a la acción del sulfato de sodio, se ha registrado la emisión acústica durante ensayos de cristalización de sales en el laboratorio. Para ello, se han seleccionado tres piedras porosas carbonatadas utilizadas como materiales de construcción en monumentos españoles (Catedrales de Oviedo, Murcia y Seo Vella de Lérida. La emisión acústica detectada durante las diferentes etapas de los ciclos (inmersión, secado y enfriamiento se ha interpretado como debida al comportamiento de la sal en el interior de la piedra. Mediante esta técnica se ha confirmado que este comportamiento depende de las características de la sal (solubilidad, diferentes estados de hidratación y el polimorfismo del sulfato de sodio anhidro y de la porosidad y configuración del sistema poroso de las rocas.

  18. Improved quality control of carbon-14 labelled compounds

    International Nuclear Information System (INIS)

    IUT Ltd is a producer of carbon-14 labelled organic compounds like benzene, methanol, phenol, formaldehyde, Na-acetates and also special ordered compounds. The quality control of these compounds is carried out by means of HPLC and GC-MS due to chemical purity. Molar activity was determined by Liquid Scintillation Counting and HPLC being equipped by a radioactivity detector. Unfortunately the accuracy of the activity determination was arrived only ±4% relatively. This error is too high because of the large dilution factors. In respect of the IUT accreditation as an analytical laboratory in Germany the accuracy had to be improved remarkably. Therefore the GC-MS-determination of molar activities of labelled compounds is used as the 14C-labelled compound. A special evaluation code is used to determine the enrichment values relative to the unlabelled molecules. Taking into account the results of GC-MS the accuracy of molar activity determination is improved to ±2%. The spectra evaluation is demonstrated and some examples are discussed

  19. Carbonates in leaching reactions in context of 14C dating

    Science.gov (United States)

    Michalska, Danuta; Czernik, Justyna

    2015-10-01

    Lime mortars as a mixture of binder and aggregate may contain carbon of various origins. If the mortars are made of totally burnt lime, radiocarbon dating of binder yields the real age of building construction. The presence of carbonaceous aggregate has a significant influence on the 14C measurements results and depending on the type of aggregate and fraction they may cause overaging. Another problem, especially in case of hydraulic mortars that continue to be chemically active for a very long time, is the recrystallization usually connected with rejuvenation of the results but also, depending on local geological structures, with so called reservoir effect yielding apparent ages. An attempt in separating the binder from other carbonaceous components successfully was made for samples from Israel by Nawrocka-Michalska et al. (2007). The same preparation procedure, after taking into account the petrographic composition, was used for samples coming from Poland, Nawrocka et al. (2009). To verify the procedure used previously for non-hydraulic samples determination an experimental tests on carbonaceous mortars with crushed bricks from Novae in Bulgaria were made. Additionally, to identify different carbonaceous structures and their morphology, a cathodoluminescence and scanning electron microscope with electron dispersive spectrometer were applied. The crushed bricks and brick dust used in mortars production process have been interpreted as an alternative use to other pozzolanic materials. The reaction between lime and pozzolanic additives take place easily and affects the rate and course of carbonates decomposition in orthophosphric acid, during the samples pretreatment for dating. The composition of the Bulgarian samples together with influence of climate conditions on mortar carbonates do not allow for making straightforward conclusions in chronology context, but gives some new guidelines in terms of hydraulic mortars application for dating. This work has mainly

  20. Incorrect interpretation of carbon mass balance biases global vegetation fire emission estimates.

    Science.gov (United States)

    Surawski, N C; Sullivan, A L; Roxburgh, S H; Meyer, C P Mick; Polglase, P J

    2016-01-01

    Vegetation fires are a complex phenomenon in the Earth system with many global impacts, including influences on global climate. Estimating carbon emissions from vegetation fires relies on a carbon mass balance technique that has evolved with two different interpretations. Databases of global vegetation fire emissions use an approach based on 'consumed biomass', which is an approximation to the biogeochemically correct 'burnt carbon' approach. Here we show that applying the 'consumed biomass' approach to global emissions from vegetation fires leads to annual overestimates of carbon emitted to the atmosphere by 4.0% or 100 Tg compared with the 'burnt carbon' approach. The required correction is significant and represents ∼9% of the net global forest carbon sink estimated annually. Vegetation fire emission studies should use the 'burnt carbon' approach to quantify and understand the role of this burnt carbon, which is not emitted to the atmosphere, as a sink enriched in carbon. PMID:27146785

  1. The preparation of glucose uniformly labelled with carbon-14; Preparacion de glucosa uniformemente marcada con carbono-14

    Energy Technology Data Exchange (ETDEWEB)

    Garcia, M. D.; Suarez, C.; Rodrigo, M. E.

    1978-07-01

    The plant, (Zea mais, L) and culture conditions for an optimum production of glucose has been chosen. To achieve the labelling of glucose, photosynthesis and carboxylation are carried on, under an artificial atmosphere of 14CO{sub 2} produced from 14{sup C}-barium carbonate. Following photosynthesis the sugars are extracted, and then the extract purified by several methods. The purified glucose is finally, degraded and the specific radioactivity is determined in each of its carbon atoms. (Author) 37 refs.

  2. Chemical and biological evolution of (U-14C)phenol sorbed on activated carbon

    International Nuclear Information System (INIS)

    Methods describing the chemical and biological evolution of (U-14C)phenol adsorbed on activated carbon are given with or without the use of bacteria. Without bacteria, the (U-14C)phenol initially adsorbed is not removed from the carbon after adding a solution of unlabelled phenol through the column for eight days. With bacteria, the (U-14C)phenol initially present, is removed (60-70%) from activated carbon with a solution containing unlabelled phenol, nitrogen and phosphorus. (author)

  3. Extending the relationship between global warming and cumulative carbon emissions to multi-millennial timescales

    International Nuclear Information System (INIS)

    The transient climate response to cumulative carbon emissions (TCRE) is a highly policy-relevant quantity in climate science. The TCRE suggests that peak warming is linearly proportional to cumulative carbon emissions and nearly independent of the emissions scenario. Here, we use simulations of the Earth System Model (ESM) from the Geophysical Fluid Dynamics Laboratory (GFDL) to show that global mean surface temperature may increase by 0.5 °C after carbon emissions are stopped at 2 °C global warming, implying an increase in the coefficient relating global warming to cumulative carbon emissions on multi-centennial timescales. The simulations also suggest a 20% lower quota on cumulative carbon emissions allowed to achieve a policy-driven limit on global warming. ESM estimates from the Coupled Model Intercomparison Project Phase 5 (CMIP5–ESMs) qualitatively agree on this result, whereas Earth System Models of Intermediate Complexity (EMICs) simulations, used in the IPCC 5th assessment report to assess the robustness of TCRE on multi-centennial timescales, suggest a post-emissions decrease in temperature. The reason for this discrepancy lies in the smaller simulated realized warming fraction in CMIP5–ESMs, including GFDL ESM2M, than in EMICs when carbon emissions increase. The temperature response to cumulative carbon emissions can be characterized by three different phases and the linear TCRE framework is only valid during the first phase when carbon emissions increase. For longer timescales, when emissions tape off, two new metrics are introduced that better characterize the time-dependent temperature response to cumulative carbon emissions: the equilibrium climate response to cumulative carbon emissions and the multi-millennial climate response to cumulative carbon emissions. (letter)

  4. Contribution of surface plasmon decay to secondary electron emission from an Al surface

    Energy Technology Data Exchange (ETDEWEB)

    Werner, Wolfgang S. M.; Salvat-Pujol, Francesc; Smekal, Werner; Khalid, Rahila; Aumayr, Friedrich; Stoeri, Herbert [Institute of Applied Physics, Vienna University of Technology, Wiedner Hauptstrasse 8-10, A 1040 Vienna (Austria); Ruocco, Alessandro; Stefani, Giovanni [Dipartimento di Fisica and Unita CNISM, Universita Roma Tre, via della Vasca Navale 84, I-00146 Rome (Italy)

    2011-10-31

    Spectra of secondary electrons (SE) emitted from a polycrystalline Al surface have been measured in coincidence with 500 eV-electrons for energy losses between 10 and 155 eV. The spectra for a given energy loss are qualitatively similar, consisting of surface and volume plasmon decay and a contribution attributable to direct electron-electron scattering. The similarity of the contribution of surface and volume plasmon decay in the SE spectra proves directly that electron multiple scattering is governed by a Markov-type process. The average value of the surface plasmon decay contribution to the SE spectrum amounts to {approx}25%.

  5. Impact of Carbon Quota Allocation Mechanism on Emissions Trading: An Agent-Based Simulation

    Directory of Open Access Journals (Sweden)

    Wei Jiang

    2016-08-01

    Full Text Available This paper establishes an agent-based simulation system of the carbon emissions trading in accordance with the complex feature of the trading process. This system analyzes the impact of the carbon quota allocation mechanism on emissions trading for three different aspects including the amount of emissions reduction, the economic effect on the emitters, and the emissions reduction cost. Based on the data of the carbon emissions of different industries in China, several simulations were made. The results indicate that the emissions trading policy can effectively reduce carbon emissions in a perfectly competitive market. Moreover, by comparing separate quota allocation mechanisms, we obtain the result that the scheme with a small extent quota decrease in a comprehensive allocation mechanism can minimize the unit carbon emission cost. Implementing this scheme can also achieve minimal effects of carbon emissions limitation on the economy on the basis that the environment is not destroyed. However, excessive quota decrease cannot promote the emitters to reduce emission. Taking into account that several developing countries have the dual task of limiting carbon emissions and developing the economy, it is necessary to adopt a comprehensive allocation mechanism of the carbon quota and increase the initial proportion of free allocation.

  6. Massive and prolonged deep carbon emissions associated with continental rifting

    Science.gov (United States)

    Lee, Hyunwoo; Muirhead, James D.; Fischer, Tobias P.; Ebinger, Cynthia J.; Kattenhorn, Simon A.; Sharp, Zachary D.; Kianji, Gladys

    2016-02-01

    Carbon from Earth’s interior is thought to be released to the atmosphere mostly via degassing of CO2 from active volcanoes. CO2 can also escape along faults away from active volcanic centres, but such tectonic degassing is poorly constrained. Here we use measurements of diffuse soil CO2, combined with carbon isotopic analyses to quantify the flux of CO2 through fault systems away from active volcanoes in the East African Rift system. We find that about 4 Mt yr-1 of mantle-derived CO2 is released in the Magadi-Natron Basin, at the border between Kenya and Tanzania. Seismicity at depths of 15-30 km implies that extensional faults in this region may penetrate the lower crust. We therefore suggest that CO2 is transferred from upper-mantle or lower-crustal magma bodies along these deep faults. Extrapolation of our measurements to the entire Eastern rift of the rift system implies a CO2 flux on the order of tens of megatonnes per year, comparable to emissions from the entire mid-ocean ridge system of 53-97 Mt yr-1. We conclude that widespread continental rifting and super-continent breakup could produce massive, long-term CO2 emissions and contribute to prolonged greenhouse conditions like those of the Cretaceous.

  7. Examining the Efforts of a Small, Open Economy to Reduce Carbon Emissions

    DEFF Research Database (Denmark)

    Levitt, Clinton J.; Saaby Pedersen, Morten; Sørensen, Anders

    2015-01-01

    It is generally understood that greenhouse gasses produced by human activities are having a warming effect on the climate. Discussions concerning efforts to curb carbon dioxide emissions often focus on large countries. However, considerable resources have been spent to reduce carbon dioxide...... faced by a large set of the world's economies. This paper has three objectives: (1) investigate the outcome of Denmark's efforts to reduce its carbon emissions by characterizing the relationship between Denmark's macroeconomic activity and carbon emissions; (2) determine the carbon content of Danish...... trade and document the important effects that growing trade with China has had on Danish consumption emissions; and (3), investigate the robustness of measures of consumption emissions under varying information requirements. Our analysis of the outcomes of Danish efforts to reduce carbon emissions...

  8. Uptake of bomb-produced carbon-14 by the Pacific Ocean

    International Nuclear Information System (INIS)

    Collection of seawater samples for carbon-14 analysis was performed from 1957 through 1972. The dissolved inorganic carbon was extracted on board the ships and returned to the laboratory for processing. Samples were analyzed for carbon-14 by gas proportional counting of acetylene prepared by conversion of carbon dioxide to acetylene via lithium carbide. Carbon-14 results are reported for 312 surface and 96 sub-surface Pacific Ocean samples and for 34 surface and 53 sub-surface Indian Ocean samples. The precision of measurements was generally from 0.5 to 1.5 percent (one-sigma). The purpose of the seawater measurements was to determine the distribution of bomb carbon-14 in the surface of the Pacific and Indian Oceans, the change in carbon-14 concentration with depth, and the rate of uptake of bomb carbon-14 by the oceans. The oceans are the largest reservoir of exchangeable carbon. The CO2 of the atmosphere exchanges with that of the sea through molecular exchange. In the surface Pacific, a strong latitudinal variation in carbon-14 concentration was found. By 1971, maxima of about 25 percent above pre-bomb levels were found at mid-latitudes of both hemispheres; this finding is attributed to relatively weak vertical mixing in the gyral circulation systems. A 1971 equatorial excess of only about 11 percent is caused by upwelling of sub-surface water and mixture of low carbon-14 Peru Current water into the equatorial system. South of the Antarctic Convergence surface radiocarbon levels rapidly decrease. To the North of the North Pacific gyre maximum, carbon-14 levels show a minimum at about 400N, apparently due to an influx of low carbon-14 water from north of Japan. Levels then rise to a maximum at 450N to 480N, before decreasing further north

  9. Hard-X-ray emission lines from the decay of 44Ti in the remnant of supernova 1987A.

    Science.gov (United States)

    Grebenev, S A; Lutovinov, A A; Tsygankov, S S; Winkler, C

    2012-10-18

    It is assumed that the radioactive decay of (44)Ti powers the infrared, optical and ultraviolet emission of supernova remnants after the complete decay of (56)Co and (57)Co (the isotopes that dominated the energy balance during the first three to four years after the explosion) until the beginning of active interaction of the ejecta with the surrounding matter. Simulations show that the initial mass of (44)Ti synthesized in core-collapse supernovae is (0.02-2.5) × 10(-4) solar masses (M circled dot). Hard X-rays and γ-rays from the decay of this (44)Ti have been unambiguously observed from Cassiopeia A only, leading to the suggestion that values of the initial mass of (44)Ti near the upper bound of the predictions occur only in exceptional cases. For the remnant of supernova 1987A, an upper limit to the initial mass of (44)Ti of supernova 1987A in the narrow band containing two direct-escape lines of (44)Ti at 67.9 and 78.4 keV. The measured line fluxes imply that this decay provided sufficient energy to power the remnant at late times. We estimate that the initial mass of (44)Ti was (3.1 ± 0.8) × 10(-4), which is near the upper bound of theoretical predictions. PMID:23075986

  10. Performance assessment of carbonation process integrated with coal fired power plant to reduce CO2 (carbon dioxide) emissions

    International Nuclear Information System (INIS)

    This paper presents a novel approach to recover energy from mineral carbonation process, one of the CCS (carbon capture and storage) technologies, to reduce its additional energy demand and reports the feasibility of integrating a carbonation process with an existing power plant for reducing CO2 (carbon dioxide) emission. A thermodynamic mass and energy flow model of the carbonation process is developed using Matlab/Simulink software for a range of carbonation temperatures using two naturally available feedstocks, namely serpentine and olivine. The CO2 emissions are reduced if a carbonation system is implemented in the power plant, though the power generation efficiency and net power output are reduced too due to the large amount of extra energy required for the grinding of feedstock and the compression of CO2. The existing power plant efficiency was found to be 36.1%. If a carbonation system is incorporated, the plant efficiency reduces to 22% and 24% using serpentine and olivine feedstocks respectively. However, a significant amount of heat energy can be recovered from exothermic reaction of carbonation and carbonated products. The power plant efficiency can be increased to 35% and 34% again, respectively, when energy from carbonation reaction and carbonated products can be recovered appropriately. - Highlights: • Mineral carbonation technology is one of the carbon capture and storage technologies. • Exothermic heat energy can be recovered from mineral carbonation process. • Mineral carbonation process is energy self-sufficient. • Thermodynamic mass and energy balance model is developed for mineral carbonation

  11. Use of the small proportional counter for carbon 14 measurement in 10 milligram carbon samples

    International Nuclear Information System (INIS)

    Ten years ago, the measurement of C-14/C-12 ratios in 10 milligram carbon samples seemed to be technically out of reach. However, two developments that make this goal possible have recently occurred: the first is an entirely new mass-spectrometric separation of C-14 and C-12 ions and their subsequent estimation by counting, while the second is simply the extension of conventional proportional counter operation (using CO2 as counter gas) to very small size carbon samples. The first method is very fast, precise, and capable of treating samples of even sub-milligram size, but requires an expensive installation. The second method is slow (counting times of two months or more are necessary), can probably be made sufficiently precise to handle most problems, works down to sample sizes of 10 mg carbon, and is relatively inexpensive, especially to install in already existing radiocarbon laboratories. It is this second method and its implications that are discussed in the present paper

  12. Life cycle study. Carbon dioxide emissions lower in electric heating than in oil heating

    Energy Technology Data Exchange (ETDEWEB)

    Heikkinen, A.; Jaervinen, P.; Nikula, A.

    1996-11-01

    A primary objective of energy conservation is to cut carbon dioxide emissions. A comparative study on the various heating forms, based on the life cycle approach, showed that the carbon dioxide emissions resulting form heating are appreciably lower now that electric heating has become more common. The level of carbon dioxide emissions in Finland would have been millions of tonnes higher had oil heating been chosen instead of electric heating. (orig.)

  13. Decomposition of Ireland’s Carbon Emissions From 1990-2010: an Extended Kaya Identity

    OpenAIRE

    O' Mahony, Tadhg

    2013-01-01

    In recent decades, Ireland has been an important example of a development pathway where rapid economic growth was accompanied by rising energy demand and increasing carbon emissions. Understanding the driving forces of carbon emissions is necessary for policy formulation and decomposition analysis is widely used for this purpose. This study uses an extended Kaya identity as the scheme and applies the log mean Divisia index (LMDI I) as the decomposition technique. Change in carbon emissions is...

  14. Greenhouse Gas Emission Accounting and Management of Low-Carbon Community

    OpenAIRE

    Dan Song; Meirong Su; Jin Yang; Bin Chen

    2012-01-01

    As the major source of greenhouse gas (GHG) emission, cities have been under tremendous pressure of energy conservation and emission reduction for decades. Community is the main unit of urban housing, public facilities, transportation, and other properties of city's land use. The construction of low-carbon community is an important pathway to realize carbon emission mitigation in the context of rapid urbanization. Therefore, an efficient carbon accounting framework should be proposed for CO2 ...

  15. Research on Spatial-Temporal Characteristics and Driving Factor of Agricultural Carbon Emissions in China

    Institute of Scientific and Technical Information of China (English)

    TIAN Yun; ZHANG Jun-biao; HE Ya-ya

    2014-01-01

    Macroscopic grasp of agricultural carbon emissions status, spatial-temporal characteristics as well as driving factors are the basic premise in further research on China’s agricultural carbon emissions. Based on 23 kinds of major carbon emission sources including agricultural materials inputs, paddy ifeld, soil and livestock breeding, this paper ifrstly calculated agricultural carbon emissions from 1995 to 2010, as well as 31 provinces and cities in 2010 in China. We then made a decomposed analysis to the driving factors of carbon emissions with logarithmic mean Divisia index (LMDI) model. The results show:(1) The amount of agricultural carbon emissions is 291.1691 million t in 2010. Compared with 249.5239 million t in 1995, it increased by 16.69%, in which, agricultural materials inputs, paddy ifeld, soil, enteric fermentation, and manure management accounted for 33.59, 22.03, 7.46, 17.53 and 19.39%of total agricultural carbon emissions, respectively. Although the amount exist ups and downs, it shows an overall trend of cyclical rise; (2) There is an obvious difference among regions:the amount of agricultural carbon emissions from top ten zones account for 56.68%, while 9.84%from last 10 zones. The traditional agricultural provinces, especially the major crop production areas are the main source regions. Based on the differences of carbon emission rations, 31 provinces and cities are divided into ifve types, namely agricultural materials dominant type, paddy ifeld dominant type, enteric fermentation dominant type, composite factors dominant type and balanced type. The agricultural carbon emissions intensity in west of China is the highest, followed by the central region, and the east zone is the lowest; (3) Compared with 1995, efifciency, labor and structure factors cut down carbon emissions by 65.78, 27.51 and 3.19%, respectively;while economy factor increase carbon emissions by 113.16%.

  16. Research on urban road congestion pricing strategy considering carbon dioxide emissions

    OpenAIRE

    Yitian Wang; Zixuan Peng; Keming Wang; Xiaolin Song; Baozhen Yao; Tao Feng

    2015-01-01

    Congestion pricing strategy has been recognized as an effective countermeasure in the practical field of urban traffic congestion mitigation. In this paper, a bi-level programming model considering carbon dioxide emission is proposed to mitigate traffic congestion and reduce carbon dioxide emissions. The objective function of the upper level model is to minimize the sum of travel costs and the carbon dioxide emissions costs. The lower level is a multi-modal transportation network equilibrium ...

  17. International oil price’s impacts on carbon emission in China’s transportation industry

    OpenAIRE

    Guoxing Zhang; Sujie Cheng

    2014-01-01

    Purpose: This paper analyses the impact mechanism of international oil price on the industrial carbon emission, and uses the partial least squares regression model to study international oil price’s impact on carbon emissions in China’s transportation industry.Design/methodology/approach: This paper chooses five independent variables of GDP, international oil price, private car population, passenger and freight transportation volume as impact factors to investigate industrial carbon emissions...

  18. News on $\\beta$-delayed particle emission from $^{14}$Be

    CERN Document Server

    Jeppesen, H; Borge, M J G; Cederkäll, J; Fynbo, H O U; Fedoseyev, V N; Hansper, V Y; Jonson, B; Markenroth, K; Mishin, V I; Nilsson, T; Nyman, G; Riisager, K; Tengblad, O; Wilhelmsen Rolander, K

    2002-01-01

    $\\beta$-delayed charged particles from $^{14}$Be have been measured and give an upper limit on $\\beta$-delayed $\\alpha$-particles of B($\\beta\\alpha$) < $\\,6.7\\times\\!10^{-5}$ and a tentative branching ratio on $\\beta$-delayed tritons of $7.5\\times\\!10^{-5}$ < B($\\beta$t) < $\\,3.9\\times\\!10^{-4}$. We combine the knowledge on $\\beta$-delayed particles from $^{14}$Be to deduce information on the $\\beta$-strength distribution.

  19. Estimating baseline carbon emissions for the Eastern Panama Canal watershed

    Energy Technology Data Exchange (ETDEWEB)

    Dale, V.H. [Environmental Sciences Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831-6036 (United States); Brown, S. [Ecosystem Services Unit, Winrock International, 1621 N Kent St, Suite 1200, Arlington, VA 22209 (United States); Calderon, M.O.; Montoya, A.S.; Martinez, R.E. [Remote Sensing Unit of the Panama Canal Watershed, Panama Canal Authority, Panama City (Panama)

    2003-07-01

    To participate in the potential market for carbon credits based on changes in the use and management of the land, one needs to identify opportunities and implement land-use based emissions reductions or sequestration projects. A key requirement of land-based carbon (C) projects is that any activity developed for generating C benefits must be additional to business-as-usual. A rule-based model was developed and used that estimates changes in land-use and subsequent carbon emissions over the next twenty years using the Eastern Panama Canal Watershed (EPCW) as a case study. These projections of changes in C stocks serve as a baseline to identify where opportunities exist for implementing projects to generate potential C credits and to position Panama to be able to participate in the emerging C market by developing a baseline under scenarios of business-as-usual and new-road development. The projections show that the highest percent change in land use for the new-road scenario compared to the business-as-usual scenario is for urban areas, and the greatest cause of C emission is from deforestation. Thus, the most effective way to reduce C emissions to the atmosphere in the EPCW is by reducing deforestation. In addition to affecting C emissions, reducing deforestation would also protect the soil and water resources of the EPCW. Yet, under the current framework of the Clean Development Mechanism (CDM), only credits arising from reforestation are allowed, which after 20 years of plantation establishment are not enough to offset the C emissions from the ongoing, albeit small, rate of deforestation in the EPCW. The study demonstrates the value of spatial regional projections of changes in land cover and C stocks: The approach helps a country identify its potential greenhouse gas (GHG) emission liabilities into the future and provides opportunity for the country to plan alternative development pathways; It could be used by potential project developers to identify which types

  20. Does pro-environmental behaviour affect carbon emissions?

    International Nuclear Information System (INIS)

    The primary focus of this research is to explore the effect of pro-environmental behaviour on CO2 emissions in relation to heating, electricity and transport activities in the residential sector. Changing such behaviour has considerable potential for conserving energy and is an important target of environmental policies which are designed to decrease energy consumption. It is hypothesized that people who consciously act in a pro-environmental way do not necessarily have lower CO2 emissions more than those who do not undertake environmental activities. Data about residential energy use is based on a survey carried out in Hungary in 2010 with a sample of 1012 people. Latent cluster analysis (LCA) was conducted based on data about the reported pro-environmental behavior in the survey and four clusters were identified. Relevant sociostructural and structural factors were also inverstigated. Results of the data analysis show that no significant difference is found between the impacts of environmentally aware and environmentally unaware consumers, i.e. both ‘Brown’ and ‘Supergreen’ consumers consume approximately the same amount of energy and produce approximately the same amount of carbon emissions because the motivation-driven activities of ‘Supergreens’ are offset by structural factors

  1. Can a unilateral carbon tax reduce emissions elsewhere?

    Energy Technology Data Exchange (ETDEWEB)

    Elliott, Joshua [Chicago Univ., IL (United States); Fullerton, Don [Illinois Univ., Champaign, IL (United States)

    2013-02-15

    One country that tries to reduce greenhouse gas emissions may fear that other countries get a competitive advantage and increase emissions (''leakage''). Estimates from computable general equilibrium (CGE) models such as Elliott et al (2010a,b) indicate that 15% to 25% of abatement might be offset by leakage. Yet the Fullerton et al (2012) analytical general equilibrium model shows an offsetting term with negative leakage. To derive analytical expressions, their model is quite simple, with only one good from each country or sector, a fixed stock of capital, competitive markets, and many identical consumers that purchase both goods. Their model is not intended to be realistic, but only to demonstrate the potential for negative leakage. Most CGE models do not allow for negative leakage. In this paper, we use a full CGE model with many countries and many goods to measure effects in a way that allows for negative leakage. We vary elasticities of substitution and confirm the analytical model's prediction that negative leakage depends on the ability of consumers to substitute into the untaxed good and the ability of firms to substitute from carbon emissions into labor or capital.

  2. Border adjustment for European emissions trading: Competitiveness and carbon leakage

    International Nuclear Information System (INIS)

    Unilateral or sub-global policies to combat climate change are potentially sensitive to free-riding and carbon leakage. One way of dealing with carbon leakage and competitiveness is the imposition of border adjustment measures for competing imports, for example in the form of the obligation to importers of goods to purchase and surrender emissions allowances to the authorities when importing. In this paper, we explore some implications of border adjustment measures in the EU ETS, for sectors that might be subject to carbon leakage. We examine the implications of two variants of these measures on the competitiveness of these sectors and on the global environment with the help of a multi-sector, multi-region computable general equilibrium (CGE) model of the global economy. Our calculations suggest that border adjustment might reduce the sectoral rate of leakage of the iron and steel industry rather forcefully, but that the reduction would be less for the mineral products sector, including cement. The reduction of the overall or macro rate of leakage would be modest. So, from an environmental point of view border tax adjustments would not be a very effective policy measure, but might mainly be justified by considerations of sectoral competitiveness.

  3. Border adjustment for European emissions trading: Competitiveness and carbon leakage

    Energy Technology Data Exchange (ETDEWEB)

    Kuik, Onno, E-mail: onno.kuik@ivm.vu.n [Institute for Environmental Studies, VU University Amsterdam, De Boelelaan 1085, 1081 HV Amsterdam (Netherlands); Hofkes, Marjan [Institute for Environmental Studies, VU University Amsterdam, De Boelelaan 1085, 1081 HV Amsterdam (Netherlands)

    2010-04-15

    Unilateral or sub-global policies to combat climate change are potentially sensitive to free-riding and carbon leakage. One way of dealing with carbon leakage and competitiveness is the imposition of border adjustment measures for competing imports, for example in the form of the obligation to importers of goods to purchase and surrender emissions allowances to the authorities when importing. In this paper, we explore some implications of border adjustment measures in the EU ETS, for sectors that might be subject to carbon leakage. We examine the implications of two variants of these measures on the competitiveness of these sectors and on the global environment with the help of a multi-sector, multi-region computable general equilibrium (CGE) model of the global economy. Our calculations suggest that border adjustment might reduce the sectoral rate of leakage of the iron and steel industry rather forcefully, but that the reduction would be less for the mineral products sector, including cement. The reduction of the overall or macro rate of leakage would be modest. So, from an environmental point of view border tax adjustments would not be a very effective policy measure, but might mainly be justified by considerations of sectoral competitiveness.

  4. Border adjustment for European emissions trading. Competitiveness and carbon leakage

    International Nuclear Information System (INIS)

    Unilateral or sub-global policies to combat climate change are potentially sensitive to free-riding and carbon leakage. One way of dealing with carbon leakage and competitiveness is the imposition of border adjustment measures for competing imports, for example in the form of the obligation to importers of goods to purchase and surrender emissions allowances to the authorities when importing. In this paper, we explore some implications of border adjustment measures in the EU ETS, for sectors that might be subject to carbon leakage. We examine the implications of two variants of these measures on the competitiveness of these sectors and on the global environment with the help of a multi-sector, multi-region computable general equilibrium (CGE) model of the global economy. Our calculations suggest that border adjustment might reduce the sectoral rate of leakage of the iron and steel industry rather forcefully, but that the reduction would be less for the mineral products sector, including cement. The reduction of the overall or macro rate of leakage would be modest. So, from an environmental point of view border tax adjustments would not be a very effective policy measure, but might mainly be justified by considerations of sectoral competitiveness. (author)

  5. Carbon emissions from deforestation in the Brazilian Amazon Region

    Directory of Open Access Journals (Sweden)

    V. Genovese

    2009-11-01

    Full Text Available A simulation model based on satellite observations of monthly vegetation greenness from the Moderate Resolution Imaging Spectroradiometer (MODIS was used to estimate monthly carbon fluxes in terrestrial ecosystems of Brazilian Amazon and Cerrado regions over the period 2000–2002. The NASA-CASA (Carnegie Ames Stanford Approach model estimates of annual forest production were used for the first time as the basis to generate a prediction for the standing pool of carbon in above-ground biomass (AGB; g C m−2 for forested areas of the Brazilian Amazon region. Plot-level measurements of the residence time of carbon in wood in Amazon forest from Malhi et al. (2006 were interpolated by inverse distance weighting algorithms and used with CASA to generate a new regional map of AGB. Data from the Brazilian PRODES (Estimativa do Desflorestamento da Amazônia project were used to map deforested areas. Results show that net primary production (NPP sinks for carbon varied between 4.25 Pg C yr−1 (1 Pg=1015 g and 4.34 Pg C for the region and were highest across the eastern and northern Amazon areas, whereas deforestation sources of CO2 flux from decomposition of residual woody debris were higher and less seasonal in the central Amazon than in the eastern and southern areas. Increased woody debris from past deforestation events was predicted to alter the net ecosystem carbon balance of the Amazon region to generate annual CO2 source fluxes at least two times higher than previously predicted by CASA modeling studies. Variations in climate, land cover, and forest burning were predicted to release carbon at rates of 0.5 to 1 Pg C yr−1 from the Brazilian Amazon. When direct deforestation emissions of CO2 from forest burning of between 0.2 and 0.6 Pg C yr−1 in the Legal Amazon are overlooked in regional budgets, the year-to-year variations in this net biome flux may

  6. Carbon Emissions from Deforestation in the Brazilian Amazon Region

    Science.gov (United States)

    Potter, C.; Klooster, S.; Genovese, V.

    2009-01-01

    A simulation model based on satellite observations of monthly vegetation greenness from the Moderate Resolution Imaging Spectroradiometer (MODIS) was used to estimate monthly carbon fluxes in terrestrial ecosystems of Brazilian Amazon and Cerrado regions over the period 2000-2002. The NASA-CASA (Carnegie Ames Stanford Approach) model estimates of annual forest production were used for the first time as the basis to generate a prediction for the standing pool of carbon in above-ground biomass (AGB; gC/sq m) for forested areas of the Brazilian Amazon region. Plot-level measurements of the residence time of carbon in wood in Amazon forest from Malhi et al. (2006) were interpolated by inverse distance weighting algorithms and used with CASA to generate a new regional map of AGB. Data from the Brazilian PRODES (Estimativa do Desflorestamento da Amazonia) project were used to map deforested areas. Results show that net primary production (NPP) sinks for carbon varied between 4.25 Pg C/yr (1 Pg=10(exp 15)g) and 4.34 Pg C for the region and were highest across the eastern and northern Amazon areas, whereas deforestation sources of CO2 flux from decomposition of residual woody debris were higher and less seasonal in the central Amazon than in the eastern and southern areas. Increased woody debris from past deforestation events was predicted to alter the net ecosystem carbon balance of the Amazon region to generate annual CO2 source fluxes at least two times higher than previously predicted by CASA modeling studies. Variations in climate, land cover, and forest burning were predicted to release carbon at rates of 0.5 to 1 Pg C/yr from the Brazilian Amazon. When direct deforestation emissions of CO2 from forest burning of between 0.2 and 0.6 Pg C/yr in the Legal Amazon are overlooked in regional budgets, the year-to-year variations in this net biome flux may appear to be large, whereas our model results implies net biome fluxes had actually been relatively consistent from

  7. Experimental evaluation of biomass burning emissions: Nitrogen and carbon containing compounds

    International Nuclear Information System (INIS)

    Data are presented on the nitrogen and carbon emissions of biomass burning. The results of the authors' experiments enable them to calculate new source strengths for many compounds, considering different burning stages and fire conditions on the one hand, and different fuel types and properties, on the other hand. They also presented a method for balancing elemental budgets of fires, which had already been described for carbon compounds by other authors but which is new for the nitrogen inventory. Based on their measurements they show that biomass burning contributes significantly to the global budgets of HCN, CH3CN (possibly the major source), NOx (12%), CO(22%), C2 to C4 hydrocarbons (14%), CH3Cl(41%), and probably also to the global source of C1-C5 aliphatic amines. Further, pyrogenic CO2 amounts are likely to represent a substantial contribution to the global greenhouse warming. An important result, from the study is the identification of N2 emissions, which causes a significant loss of fixed nitrogen (pyro-denitrification) in tropical ecosystems in the order of 5% to 20% of the global nitrogen fixation rate. Because of an interesting interplay between an enhanced postfire nitrogen fixation and an enhanced postfire N2O emission, it is not yet known if losses due to pyro-denitrification are balanced by nitrogen fixation

  8. Prolonged spontaneous emission and dephasing of localized excitons in air-bridged carbon nanotubes

    Science.gov (United States)

    Sarpkaya, Ibrahim; Zhang, Zhengyi; Walden-Newman, William; Wang, Xuesi; Hone, James; Wong, Chee W.; Strauf, Stefan

    2013-07-01

    The bright exciton emission of carbon nanotubes is appealing for optoelectronic devices and fundamental studies of light-matter interaction in one-dimensional nanostructures. However, to date, the photophysics of excitons in carbon nanotubes is largely affected by extrinsic effects. Here we perform time-resolved photoluminescence measurements over 14 orders of magnitude for ultra-clean carbon nanotubes bridging an air gap over pillar posts. Our measurements demonstrate a new regime of intrinsic exciton photophysics with prolonged spontaneous emission times up to T1=18 ns, about two orders of magnitude better than prior measurements and in agreement with values hypothesized by theorists about a decade ago. Furthermore, we establish for the first time exciton decoherence times of individual nanotubes in the time domain and find fourfold prolonged values up to T2=2.1 ps compared with ensemble measurements. These first observations motivate new discussions about the magnitude of the intrinsic dephasing mechanism while the prolonged exciton dynamics is promising for applications.

  9. Analysis and forecast of residential building energy consumption in Chongqing on carbon emissions

    Institute of Scientific and Technical Information of China (English)

    李沁; 刘猛; 钱发

    2009-01-01

    Carbon emissions mainly result from energy consumption. Carbon emissions inevitably will increase to some extent with economic expansion and rising energy consumption. We introduce a gray theory of quantitative analysis of the energy consumption of residential buildings in Chongqing,China,on the impact of carbon emission factors. Three impacts are analyzed,namely per capita residential housing area,domestic water consumption and the rate of air conditioner ownership per 100 urban households. The gray prediction model established using the Chongqing carbon emission-residential building energy consumption forecast model is sufficiently accurate to achieve a measure of feasibility and applicability.

  10. Potential impact of (CET) carbon emissions trading on China's power sector: A perspective from different allowance allocation options

    International Nuclear Information System (INIS)

    In Copenhagen climate conference China government promised that China would cut down carbon intensity 40-45% from 2005 by 2020. CET (carbon emissions trading) is an effective tool to reduce emissions. But because CET is not fully implemented in China up to now, how to design it and its potential impact are unknown to us. This paper studies the potential impact of introduction of CET on China's power sector and discusses the impact of different allocation options of allowances. Agent-based modeling is one appealing new methodology that has the potential to overcome some shortcomings of traditional methods. We establish an agent-based model, CETICEM (CET Introduced China Electricity Market), of introduction of CET to China. In CETICEM, six types of agents and two markets are modeled. We find that: (1) CET internalizes environment cost; increases the average electricity price by 12%; and transfers carbon price volatility to the electricity market, increasing electricity price volatility by 4%. (2) CET influences the relative cost of different power generation technologies through the carbon price, significantly increasing the proportion of environmentally friendly technologies; expensive solar power generation in particular develops significantly, with final proportion increasing by 14%. (3) Emission-based allocation brings about both higher electricity and carbon prices than by output-based allocation which encourages producers to be environmentally friendly. Therefore, output-based allocation would be more conducive to reducing emissions in the Chinese power sector. (author)

  11. Results on ββ decay with emission of two neutrinos or Majorons in 76Ge from GERDA Phase I

    International Nuclear Information System (INIS)

    A search for neutrinoless ββ decay processes accompanied with Majoron emission has been performed using data collected during Phase I of the GERmanium Detector Array (GERDA) experiment at the Laboratori Nazionali del Gran Sasso of INFN (Italy). Processes with spectral indices n=1,2,3,7 were searched for. No signals were found and lower limits of the order of 1023 yr on their half-lives were derived, yielding substantially improved results compared to previous experiments with 76Ge. A new result for the half-life of the neutrino-accompanied ββ decay of 76Ge with significantly reduced uncertainties is also given, resulting in T1/22ν=(1.926±0.094)×1021 yr

  12. Results on $\\beta\\beta$ decay with emission of two neutrinos or Majorons in $^{76}$Ge from GERDA Phase I

    CERN Document Server

    Agostini, M; Bakalyarov, A M; Balata, M; Barabanov, I; Barros, N; Baudis, L; Bauer, C; Becerici-Schmidt, N; Bellotti, E; Belogurov, S; Belyaev, S T; Benato, G; Bettini, A; Bezrukov, L; Bode, T; Borowicz, D; Brudanin, V; Brugnera, R; Budjáš, D; Caldwell, A; Cattadori, C; Chernogorov, A; D'Andrea, V; Demidova, E V; di Vacri, A; Domula, A; Doroshkevich, E; Egorov, V; Falkenstein, R; Fedorova, O; Freund, K; Frodyma, N; Gangapshev, A; Garfagnini, A; Grabmayr, P; Gurentsov, V; Gusev, K; Hegai, A; Heisel, M; Hemmer, S; Heusser, G; Hofmann, W; Hult, M; Inzhechik, L V; Csáthy, J Janicskó; Jochum, J; Junker, M; Kazalov, V; Kihm, T; Kirpichnikov, I V; Kirsch, A; Klimenko, A; Knöpfle, K T; Kochetov, O; Kornoukhov, V N; Kuzminov, V V; Laubenstein, M; Lazzaro, A; Lebedev, V I; Lehnert, B; Liao, H Y; Lindner, M; Lippi, I; Lubashevskiy, A; Lubsandorzhiev, B; Lutter, G; Macolino, C; Majorovits, B; Maneschg, W; Medinaceli, E; Misiaszek, M; Moseev, P; Nemchenok, I; Palioselitis, D; Panas, K; Pandola, L; Pelczar, K; Pullia, A; Riboldi, S; Rumyantseva, N; Sada, C; Salathe, M; Schmitt, C; Schreiner, J; Schulz, O; Schwingenheuer, B; Schönert, S; Selivanenko, O; Shirchenko, M; Simgen, H; Smolnikov, A; Stanco, L; Stepaniuk, M; Ur, C A; Vanhoefer, L; Vasenko, A A; Veresnikova, A; von Sturm, K; Wagner, V; Walter, M; Wegmann, A; Wester, T; Wilsenach, H; Wojcik, M; Yanovich, E; Zavarise, P; Zhitnikov, I; Zhukov, S V; Zinatulina, D; Zuber, K; Zuzel, G

    2015-01-01

    A search for neutrinoless $\\beta\\beta$ decay processes accompanied with Majoron emission has been performed using data collected during Phase I of the GERmanium Detector Array (GERDA) experiment at the Laboratori Nazionali del Gran Sasso of INFN (Italy). Processes with spectral indices n = 1, 2, 3, 7 were searched for. No signals were found and lower limits of the order of 10$^{23}$ yr on their half-lives were derived, yielding substantially improved results compared to previous experiments with $^{76}$Ge. A new result for the half-life of the neutrino-accompanied $\\beta\\beta$ decay of $^{76}$Ge with significantly reduced uncertainties is also given, resulting in $T^{2\

  13. Effective theory of dark matter decay into monochromatic photons and its implications: Constraints from associated cosmic-ray emission

    International Nuclear Information System (INIS)

    We show that there exists only a quite limited number of higher dimensional operators which can naturally lead to a slow decay of dark matter particles into monochromatic photons. As each of these operators inevitably induces decays into particles other than photons, we show that the γ-lines it induces are always accompanied by a continuum flux of cosmic rays. Hence constraints on cosmic-ray fluxes imply constraints on the intensity of γ-lines and vice versa. A comparison with up to date observational bounds shows the possibilities to observe or exclude cosmic rays associated to γ-line emission, so that one could better determine the properties of the DM particle, possibly discriminating between some of the operators

  14. Results on ββ decay with emission of two neutrinos or Majorons in 76Ge from GERDA Phase I

    International Nuclear Information System (INIS)

    A search for neutrinoless ββ decay processes accompanied with Majoron emission has been performed using data collected during Phase I of the GERmanium Detector Array (GERDA) experiment at the Laboratori Nazionali del Gran Sasso of INFN (Italy). Processes with spectral indices n = 1, 2, 3, 7 were searched for. No signals were found and lower limits of the order of 1023 yr on their half-lives were derived, yielding substantially improved results compared to previous experiments with 76Ge. A new result for the half-life of the neutrino-accompanied ββ decay of 76Ge with significantly reduced uncertainties is also given, resulting in T1/22ν = (1.926 ± 0.094) @ x 1021 yr. (orig.)

  15. Preliminary study of the impact of tritium and carbon 14 releases from the Saint-Alban nuclear power plant. CRIIRAD N.04-20 V1 Report

    International Nuclear Information System (INIS)

    After having recalled the results of previous studies on the radioactivity in surface water and land environments, and outlined the need of an investigation of the tritium and carbon 14 contamination, this report defines the objectives of this investigation, the adopted methodology (choice of plants, tritium and carbon 14 dose measurements, and sampling to study time variations). It recalls some aspects of tritium and carbon 14 releases (production of radionuclides, origins of emissions in the environment, assessments by EDF). It reports the investigation and the assessment of tritium activity in a land environment and in rain waters about the investigated site, and the investigation and the assessment of carbon 14 activity within the same environment. It reports preliminary results concerning the aquatic environment

  16. Carbon Emission Effect of Land Use in Nanchang City and Its Optimization Countermeasures

    Institute of Scientific and Technical Information of China (English)

    Haisheng; CAI; Ting; ZHANG; Xueling; ZHANG

    2013-01-01

    Land use/coverage change(LUCC)exerts a profound influence on global carbon emission through changing structure and functions of ecosystem.Taking Nanchang City as an example,this study determined organic carbon emission of land ecosystem by ecosystem type method.In 2005,total carbon emission of Nanchang City was 4.826 2 Tg.In 2010,it became 5.535 9 Tg,showing a growth trend of carbon emission from land use change.The carbon emission of cropland and grassland decreased in 2005-2010,that of garden land and construction land had increase,and carbon absorption function of water land and other unused land was weakened.Due to difference of land use structure,the carbon emission of Nanchang City is varied.In 2005-2010,the rank of carbon emission from high to low is as follows:Nanchang County,Xinjian County,Jinxian County and Qingshanhu District.In combination with land use change and development plan of Nanchang City,Nanchang City should take carbon emission reduction measures,including conceding the land to forestry,returning the land to water,limiting excessive expansion of construction land,optimizing distribution of urban land use,flexibly regulating land supply policies,and establishing carbon trading legal system,to reach the objective of combining land use plan with ecological construction.

  17. Decomposition of China’s Carbon Emissions Intensity from 1995 to 2010: An Extended Kaya Identity

    OpenAIRE

    Wei Li; Qing-Xiang Ou

    2013-01-01

    This paper employs an extended Kaya identity as the scheme and utilizes the Logarithmic Mean Divisia Index (LMDI II) as the decomposition technique based on analyzing CO2 emissions trends in China. Change in CO2 emissions intensity is decomposed from 1995 to 2010 and includes measures of the effect of Industrial structure, energy intensity, energy structure, and carbon emission factors. Results illustrate that changes in energy intensity act to decrease carbon emissions intensity significantl...

  18. Affluence and emission trade-offs: evidence from Indonesian household carbon footprint

    OpenAIRE

    Irfany, M. Iqbal

    2014-01-01

    The objectives of this study are to analyze the household carbon footprint pattern in Indonesia and to analyze the determinants of the growing carbon footprint in this emerging economy. To measure the household emissions, we combine national input-output, emission database to generate sectoral CO2 emission intensities and matched these intensities with two waves of national expenditure surveys from 2005 and 2009. We then use this household CO2 emission for investigating the drivers of the ris...

  19. Emission Inventories of Carbon-containing Greenhouse Gases in and Technological Measures for Their Abatement

    Institute of Scientific and Technical Information of China (English)

    Zhuang Yahui; Zhang Hongxun; Wang Xiaoke; Li Changsheng

    2004-01-01

    The report summarizes surveys on carbon inventories and initiatives on sustainable carbon cycling taken by the Research Center for EcoEnvironmental Sciences, where the authors work/worked. The first part of the report, which appeared in the preceding issue of this journal, deals with the concept of sustainable carbon cycling, the historic evolution of carbon cycling processes in China, carbon pool enhancement, value addition,carbon sequestration and carbon balance. This very paper, as the second part of the report, covers the results of carbon dynamics modeling, emission inventories of various carbon-containing greenhouse gases and their potential abatement measures.

  20. Potential Biodiversity Benefits from International Programs to Reduce Carbon Emissions from Deforestation

    OpenAIRE

    Siikamäki, Juha; Stephen C. Newbold

    2012-01-01

    Deforestation is the second largest anthropogenic source of carbon dioxide emissions and options for its reduction are integral to climate policy. In addition to providing potentially low cost and near-term options for reducing global carbon emissions, reducing deforestation also could support biodiversity conservation. However, current understanding of the potential benefits to biodiversity from forest carbon offset programs is limited. We compile spatial data on global forest carbon, biodiv...

  1. Urban Household Carbon Emission and Contributing Factors in the Yangtze River Delta, China

    OpenAIRE

    Xu, Xibao; Tan, Yan; Chen, Shuang; Yang, Guishan; Su, Weizhong

    2015-01-01

    Carbon reduction at the household level is an integral part of carbon mitigation. This study analyses the characteristics, effects, contributing factors and policies for urban household carbon emissions in the Yangtze River Delta of China. Primary data was collected through structured questionnaire surveys in three cities in the region – Nanjing, Ningbo, and Changzhou in 2011. The survey data was first used to estimate the magnitude of household carbon emissions in different urban contexts. I...

  2. Carbon Tariffs: Impacts on Technology Choice, Regional Competitiveness, and Global Emissions

    OpenAIRE

    David F. Drake

    2011-01-01

    Carbon regulation is intended to reduce global emissions, but there is growing concern that such regulation may simply shift production to unregulated regions, potentially increasing overall carbon emissions in the process. Carbon tariffs have emerged as a possible mechanism to address this concern by imposing carbon costs on imports at the regulated region's border. Advocates claim that such a mechanism would level the playing field whereas opponents argue that such a tariff is anti-competit...

  3. Carbon taxes, consumer demand and carbon dioxide emission: a simulation analysis for the UK

    International Nuclear Information System (INIS)

    This paper examines a policy instrument that has been proposed as a means of reducing 'greenhouse gases', the introduction of a carbon tax on fossil fuels. It investigates the implication of a carbon tax for consumer prices using an input-output framework. Thus the effect of a tax on use of fossil fuels is allowed to affect consumer prices. These are then used in a micro-simulation program that features estimates of a system of demand equations obtained using 116,000 observations from the Family Expenditure System. This predicts the behavioural reaction of each household to the tax changes and the consequent effect on CO2 emission, government revenue and any distributional effects. We illustrate the impact of a variety of carbon taxes, changes to indirect tax rates and lump-sum compensatory payments. (author)

  4. Carbon Emission Trading System of New Zealand and Its Enlightenment for China

    Institute of Scientific and Technical Information of China (English)

    Yan; XIAO; Xiaoxue; LI

    2013-01-01

    The design characteristics and operation results of carbon emission trading system of New Zealand was introduced in this paper. The results suggested that taking forest carbon trade as the only one supplying source of greenhouse gas emission improved the foreseeability in forest maintenance,and strengthened the effect of forestation. According to this,the author suggested that carbon emission trading market in which forest carbon trade was the only one supplying source should be cultivated in China. A compensation mechanism that industry compensated forestry should be established. A social participated,highly united,coordinated and mutual intermediated carbon trading market should be built.

  5. Emissivity of a multibeam electron gun with a glassy carbon field-emission cathode

    Science.gov (United States)

    Bushuev, N. A.; Glukhova, O. E.; Grigor'ev, Yu. A.; Ivanov, D. V.; Kolesnikova, A. S.; Nikolaev, A. A.; Shalaev, P. D.; Shesterkin, V. I.

    2016-02-01

    A multibeam triode electron gun with a glassy carbon field-emission cathode that is intended for an O-type microwave amplifier is studied. The electric field strength and the current density at the microtips versus the distance to the center of a cell of the cathode-grid unit are calculated. Calculation data are compared with experimental results. It is shown that about 70% of the cathode current in each cell is accounted for by microtips arranged in a circumferential ring no wider than 20 μm. The field-emission current density inside the ring exceeds 40 A/cm2, and the current per microtip equals 43.1 μA.

  6. The natural thermoluminescence of meteorites. VI - Carbon-14, thermoluminescence and the terrestrial ages of meteorites

    Science.gov (United States)

    Benoit, P. H.; Jull, A. J. T.; McKeever, S. W. S.; Sears, D. W. G.

    1993-06-01

    A relationship is noted between the natural thermoluminescence (TL) levels and the C-14-derived terrestrial ages for meteorite finds from the U.S. Prairie States and Roosevelt County, NM; those in the Sahara are also in accord with calculated TL decay curves, for 'storage' temperatures equal to the approximate average annual temperatures at individual sites. This discussion is limited to the empirical correspondence between the two methodologies, and to theoretical decay curves for a single 'average' ordinary chondrite.

  7. Mechanism of field electron emission from carbon nanotubes

    Institute of Scientific and Technical Information of China (English)

    LI Zhi-bing; DENG Shao-zhi; XU Ning-sheng

    2006-01-01

    Field electron emission (FE) is a quantum tunneling process in which electrons are injected from materials (usually metals) into a vacuum under the influence of an applied electric field.In order to obtain usable electron current,the conventional way is to increase the local field at the surface of an emitter.For a plane metal emitter with a typical work function of 5 eV,an applied field of over 1000V/μm is needed to obtain a significant current.The high working field (and/or the voltage between the electrodes)has been the bottleneck for many applications of the FE technique.Since the 1960s,enormous effort has been devoted to reduce the working macroscopic field (voltage).A widely adopted idea is to sharpen the emitters to get a large surface field enhancement.The materials of emitters should have good electronic conductivity,high melting points,good chemical inertness,and high mechanical stiffness.Carbon nanotubes (CNTs) are built with such needed properties.As a quasi-one-dimensional material,the CNT is expected to have a large surface field enhancement factor.The experiments have proved the excellent FE performance of CNTs.The turn-on field (the macroscopic field for obtaining a density of 10 μA/cm2 ) of CNT based emitters can be as low as 1 V/μm.However,this turn-on field is too good to be explained by conventional theory.There are other observations,such as the non-linear Fowler-Nordheim plot and multi-peaks field emission energy distribution spectra,indicating that the field enhancement is not the only story in the FE of CNTs.Since the discovery of CNTs,people have employed more serious quantum mechanical methods,including the electronic band theory,tight-binding theory,scattering theory and density function theory,to investigate FE of CNTs.A few theoretical models have been developed at the same time.The multi-walled carbon nanotubes (MWCNTs)should be assembled with a sharp metal needle of nano-scale radius,for which the FE mechanism is more or less clear

  8. Resonant Auger decay of Ar 2p3/2-14s and 2p3/2-14p states excited by electron impact

    International Nuclear Information System (INIS)

    Auger spectra of resonantly excited 2p3/2-14s and 2p3/2-14p states in argon were measured by (e,2e) technique. The 99.2-eV scattered electrons were detected in coincidence with L3-M23M23 Auger electrons, and the experiment was performed at 343.6- and 344.9-eV electron impact to tune the energy loss to the energy of the dipole-allowed and the dipole-forbidden excitations, respectively. The resonant Auger spectra are obtained upon subtraction of the overlapping signal due to the outer-shell ionization, which was recorded at 340-eV electron-impact energy. The most intense groups of Auger transitions from 2p3/2-14s (J=1,2) and 2p3/2-14p (J=0,1,2,3) states are identified by comparison with the results of the two-step model, based on distorted-wave Born approximation with exchange and multiconfiguration descriptions of the relaxed states. The 4 s spectrum displays a substantially larger shake-up contribution than the one observed in photoexcitation experiments, which may be explained by the interference of the resonant decay path with the direct ionization excitation of the Ar 3p subshell. The majority of the observed 4p signal is assigned to the monopole and quadrupole excitations of the ground state.

  9. Urban Traffic Congestion Pricing Model with the Consideration of Carbon Emissions Cost

    Directory of Open Access Journals (Sweden)

    Jian Wang

    2014-02-01

    Full Text Available As one of the most effective traffic demand management opinions, congestion pricing can reduce private car travel demand and the associated carbon dioxide emissions. First, we summarized the status quo of transport carbon dioxide emission charges and congestion pricing, and then, we analyzed the characteristics of urban transport carbon dioxide emissions. Then, we proposed a (pricing framework in which carbon emission costs would be considered as part of the generalized cost of travel. Based on this framework, this paper developed a bi-level mathematical model to optimize consumer surplus, using congestion and carbon emission charges as the control variables. A dissect search algorithm was used to solve the bi-level program model, and a numerical example was given to illustrate the methodology. This paper incorporates the emission pricing into the congestion pricing model, while considering two modes, and puts forward suitable proposals for the implementation of an urban traffic congestion pricing policy in China.

  10. Synthesis of carbon-14 labelled indolic 5HT{sub 1} receptor agonists

    Energy Technology Data Exchange (ETDEWEB)

    Waterhouse, Ian; Cable, K.M.; Fellows, Ian; Wipperman, M.D.; Sutherland, D.R. [Glaxo Wellcome Research and Development, Stevenage (United Kingdom). Isotope Chemistry Unit

    1996-11-01

    Syntheses of carbon-14 labelled versions of indolic 5HT{sub 1} agonists sumatriptan (GR43175), GR40370 and naratriptan (GR85548) are described. Introduction of the label via cyanation of ketoformanilides, formed by oxidative cleavage of an indole ring, ensured incorporation of carbon-14 at the metabolically stable C-2 position of the indole. (author).

  11. Review of hidden carbon emissions, trade, and labor income share in China, 2001–2011

    International Nuclear Information System (INIS)

    Coordinated development between the economy and the environment is currently one of the most important issues in China. By establishing models concerning labor income share and hidden carbon emissions, and taking trade as the link in their relationship, this study puts forward the scale effects, technological effects, and structural effects that relate to labor income share under the function of trade. We then establish multi-index and multi-indicator constitutive (MIMIC) equation to measure the ratio of hidden carbon emissions to total emissions, which is further considered the basis of the measurement model. Results of regression analysis carried out on labor income share show that hidden carbon emissions do have a positive effect on labor income share. In the meantime, we also prove that under scale effects, technological effects, and the structural effects of trade, hidden carbon emissions affect labor income shares in different directions. Our conclusions and policy implications are obtained from the calculated results. - Highlights: • This study establishes models concerning labor income share and hidden carbon emissions. • MIMIC is established to measure the ratio of hidden carbon emissions to total discharge. • Hidden carbon emissions have a positive effect on labor income share. • Hidden carbon emissions have various effects on the labor income share

  12. Optically active substituted polyacetylene@carbon nanotube hybrids: Preparation, characterization and infrared emissivity property study

    Energy Technology Data Exchange (ETDEWEB)

    Bu, Xiaohai; Zhou, Yuming, E-mail: ymzhou@seu.edu.cn; Zhang, Tao; Wang, Yongjuan; Zhang, Zewu; He, Man

    2014-08-15

    Optically active substituted polyacetylene@multiwalled carbon nanotubes (SPA@MWCNTs) nanohybrids were fabricated by wrapping helical SPA copolymers onto the surface of modified nanotubes through ester bonding linkage. SPA copolymer based on chiral phenylalanine and serine was pre-polymerized by a rhodium zwitterion catalyst in THF, and evidently proved to possess strong optical activity and adopt a predominately one-handed helical conformation. Various characterizations including Fourier transform infrared spectroscopy (FT-IR), X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), and transmission electron microscopy (TEM) demonstrated that the SPA had been covalently grafted onto the nanotubes without destroying their original graphite structure. The wrapped SPA was found to exhibit an enhancement in thermal stability and still maintained considerable optical activity after grafting. The infrared emissivity property of the nanohybrids at 8–14 μm was investigated in addition. The results indicated that the SPA@MWCNTs hybrid matrix could possess a much lower infrared emissivity value (ε=0.707) than raw MWCNTs, which might be due to synergistic effect of the unique helical conformation of optically active SPA and strengthened interfacial interaction between the organic polymers and inorganic nanoparticles. - Graphical abstract: Optically active SPA@MWCNTs nanohybrids with low infrared emissivity. - Highlights: • Synthesis of optically active SPA copolymer derived from serine and phenylalanine. • Preparation and characterization of optically active SPA@MWCNTs nanohybrids. • Application study of the SPA@MWCNTs nanohybrids (ε=0.707) in lowering the infrared emissivity.

  13. Optically active substituted polyacetylene@carbon nanotube hybrids: Preparation, characterization and infrared emissivity property study

    International Nuclear Information System (INIS)

    Optically active substituted polyacetylene@multiwalled carbon nanotubes (SPA@MWCNTs) nanohybrids were fabricated by wrapping helical SPA copolymers onto the surface of modified nanotubes through ester bonding linkage. SPA copolymer based on chiral phenylalanine and serine was pre-polymerized by a rhodium zwitterion catalyst in THF, and evidently proved to possess strong optical activity and adopt a predominately one-handed helical conformation. Various characterizations including Fourier transform infrared spectroscopy (FT-IR), X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), and transmission electron microscopy (TEM) demonstrated that the SPA had been covalently grafted onto the nanotubes without destroying their original graphite structure. The wrapped SPA was found to exhibit an enhancement in thermal stability and still maintained considerable optical activity after grafting. The infrared emissivity property of the nanohybrids at 8–14 μm was investigated in addition. The results indicated that the SPA@MWCNTs hybrid matrix could possess a much lower infrared emissivity value (ε=0.707) than raw MWCNTs, which might be due to synergistic effect of the unique helical conformation of optically active SPA and strengthened interfacial interaction between the organic polymers and inorganic nanoparticles. - Graphical abstract: Optically active SPA@MWCNTs nanohybrids with low infrared emissivity. - Highlights: • Synthesis of optically active SPA copolymer derived from serine and phenylalanine. • Preparation and characterization of optically active SPA@MWCNTs nanohybrids. • Application study of the SPA@MWCNTs nanohybrids (ε=0.707) in lowering the infrared emissivity

  14. Enhanced Field-Emission Performance from Carbon Nanotube Emitters on Nickel Foam Cathodes

    Science.gov (United States)

    Song, Meng; Xu, Peng; Han, Lijing; Yi, Lan; Wang, Xu; Li, Zhenhua; Shang, Xuefu; Wang, Xiumin; Wu, Huizhen; Zhao, Pei; Song, Yenan; Wang, Miao

    2016-04-01

    We present a three-dimensionally configured cathode with enhanced field-emission performance formed by combining carbon nanotube (CNT) emitters with a nickel foam (NiF) substrate via a conventional screen-printing technique. The CNT/NiF cathode has low turn-on electric field of 0.53 V μm-1 (with current density of 10 μA cm-2) and threshold electric field of 0.87 V μm-1 (with current density of 0.1 mA cm-2), and a very high field enhancement factor of 1.4 × 104. The porous structure of the NiF substrate can greatly improve the field-emission properties due to its large specific surface area that can accommodate more CNTs and increase the emitter density, as well as its high electrical and thermal conductivities that facilitate current transition and heat dissipation in the cathode. Most importantly, the local electric field was also enhanced by the multistage effect resulting from the rough metal surface, which furthermore leads to a high field enhancement factor. We believe that this improved field-emission performance makes such cathodes promising candidates for use in various field-emission applications.

  15. Carbon isotope (14C, 12C) measurements to quantify sources of atmospheric carbon monoxide in urban air

    International Nuclear Information System (INIS)

    Atmospheric air samples were collected during the Winter of 1989-90 in Albuquerque, NM USA, for carbon isotope (14C, 12C) analysis of carbon monoxide (CO). An experimental sample design was prepared to target periods when the concentration of CO exceeds the 9 μL/L (volume fraction), 8 hour National Ambient Air Quality Standard (NAAQS) and during periods of attainment. Sampling sites, time of day, sampling duration, and meteorology were carefully considered so that source impacts be optimal. A balanced sampling factorial design was used to yield maximum information from the constraints imposed; the number of samples was limited by the number of sample canisters available, time, and resources. Carbon isotope measurements of urban air, ''clean-air'' background from Niwot Ridge, Colorado, average (wood) logs and oxygenated-gasolines were used in a 3-source model to calculate the contribution of woodburning to the total atmospheric CO burden in Albuquerque. Results show that the estimated fractional contribution of residential wood combustion (Θ' RWC) ranged from 0 to 0.30 of CO concentrations corrected for ''clean-air'' background. For these same samples, the respective CO concentrations attributed to woodburning range from 0 to 0.90 μmol/mol (mole fraction), well below the NAAQS. In all cases, fossil CO is the predominant source of ambient CO concentrations ranging from 0.96 to 6.34 μmol/mol. A final comment is made on the potential of fossil CO measurements as an indirect tracer of atmospheric benzene, relevant to exposure risk estimates of motor vehicle emissions and occupational health and safety standards. (author). 26 refs, 3 figs, 4 tabs

  16. Cavity-enhanced light emission from electrically driven carbon nanotubes

    Science.gov (United States)

    Pyatkov, Felix; Fütterling, Valentin; Khasminskaya, Svetlana; Flavel, Benjamin S.; Hennrich, Frank; Kappes, Manfred M.; Krupke, Ralph; Pernice, Wolfram H. P.

    2016-06-01

    An important advancement towards optical communication on a chip would be the development of integratable, nanoscale photonic emitters with tailored optical properties. Here we demonstrate the use of carbon nanotubes as electrically driven high-speed emitters in combination with a nanophotonic cavity that allows for exceptionally narrow linewidths. The one-dimensional photonic crystal cavities are shown to spectrally select desired emission wavelengths, enhance intensity and efficiently couple light into the underlying photonic network with high reproducibility. Under pulsed voltage excitation, we realize on-chip modulation rates in the GHz range, compatible with active photonic networks. Because the linewidth of the molecular emitter is determined by the quality factor of the photonic crystal, our approach effectively eliminates linewidth broadening due to temperature, surface interaction and hot-carrier injection.

  17. Analytical model of carbon dioxide emission with energy payback effect

    International Nuclear Information System (INIS)

    An analytical model is proposed to account for carbon emission behaviour during replacement of power source from fossil fuel to renewable energy in which sustainability of energy supply is stressed. Logistic function of time is assumed for producing renewable power sources. Analyses show that energy payback time (EPT) should be much shorter than the doubling time of manufacturing cycle to secure adequate available energy during, as well as after, the replacement. A nuclear plant, small hydropower plant, wind power plant and photovoltaic cell are taken as representative candidates and investigated as options to replace fossil power until toward the end of this century. Nuclear or small hydropower plants are promising candidates but the photovoltaic cell needs further development efforts to reduce EPT and avoid energy expense after the replacement. (author)

  18. Energy use and carbon emissions: Some international comparisons

    International Nuclear Information System (INIS)

    This report examines international energy use patterns, trends, and energy-related carbon emissions since 1970. The main focus of this study is on the developed countries, represented by the members of the organization for Economic Cooperation and Development (OECD). The study is organized as follows: (1) the OECD is placed in a world context; (2) aggregate-level information is then presented for an important part of the OECD, namely the Group of Seven (G-7) major industrialized countries (the US, Canada, Japan, the United Kingdom, France, Italy, and Germany -- defined in this report as western Germany only, except where indicated); and (3) individual economic sectors within the G-7 countries are broken out for detailed review

  19. Carbon emissions from decomposition of fire-killed trees following a large wildfire in Oregon, United States

    Science.gov (United States)

    Campbell, John L.; Fontaine, Joseph B.; Donato, Daniel C.

    2016-03-01

    A key uncertainty concerning the effect of wildfire on carbon dynamics is the rate at which fire-killed biomass (e.g., dead trees) decays and emits carbon to the atmosphere. We used a ground-based approach to compute decomposition of forest biomass killed, but not combusted, in the Biscuit Fire of 2002, an exceptionally large wildfire that burned over 200,000 ha of mixed conifer forest in southwestern Oregon, USA. A combination of federal inventory data and supplementary ground measurements afforded the estimation of fire-caused mortality and subsequent 10 year decomposition for several functionally distinct carbon pools at 180 independent locations in the burn area. Decomposition was highest for fire-killed leaves and fine roots and lowest for large-diameter wood. Decomposition rates varied somewhat among tree species and were only 35% lower for trees still standing than for trees fallen at the time of the fire. We estimate a total of 4.7 Tg C was killed but not combusted in the Biscuit Fire, 85% of which remains 10 years after. Biogenic carbon emissions from fire-killed necromass were estimated to be 1.0, 0.6, and 0.4 Mg C ha-1 yr-1 at 1, 10, and 50 years after the fire, respectively; compared to the one-time pyrogenic emission of nearly 17 Mg C ha-1.

  20. Electricity generation: options for reduction in carbon emissions.

    Science.gov (United States)

    Whittington, H W

    2002-08-15

    Historically, the bulk production of electricity has been achieved by burning fossil fuels, with unavoidable gaseous emissions, including large quantities of carbon dioxide: an average-sized modern coal-burning power station is responsible for more than 10 Mt of CO(2) each year. This paper details typical emissions from present-day power stations and discusses the options for their reduction. Acknowledging that the cuts achieved in the past decade in the UK CO(2) emissions have been achieved largely by fuel switching, the remaining possibilities offered by this method are discussed. Switching to less-polluting fossil fuels will achieve some measure of reduction, but the basic problem of CO(2) emissions continues. Of the alternatives to fossil fuels, only nuclear power represents a zero-carbon large-scale energy source. Unfortunately, public concerns over safety and radioactive waste have still to be assuaged. Other approaches include the application of improved combustion technology, the removal of harmful gases from power-station flues and the use of waste heat to improve overall power-station efficiency. These all have a part to play, but many consider our best hope for emissions reduction to be the use of renewable energy. The main renewable energy contenders are assessed in this paper and realistic estimates of the contribution that each could provide are indicated. It appears that, in the time-scale envisaged by planners for reduction in CO(2) emission, in many countries renewable energy will be unlikely to deliver. At the same time, it is worth commenting that, again in many countries, the level of penetration of renewable energy will fall short of the present somewhat optimistic targets. Of renewable options, wind energy could be used in the short to medium term to cover for thermal plant closures, but for wind energy to be successful, the network will have to be modified to cope with wind's intermittent nature. Globally, hydroelectricity is currently the

  1. Decay kinetics of the green emission in PbWO.sub.4./sub.:Mo

    Czech Academy of Sciences Publication Activity Database

    Mihóková, Eva; Nikl, Martin; Boháček, Pavel; Babin, V.; Krasnikov, A.; Stolovich, S.; Zazubovich, S.; Vedda, C.; Martini, M.; Grabowski, T.

    102-103, - (2003), s. 618-622. ISSN 0022-2313 R&D Projects: GA ČR GA202/01/0753 Institutional research plan: CEZ:AV0Z1010914 Keywords : decay kinetics * lead tungstate Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 1.314, year: 2003

  2. Can a many-nucleon structure be visible in bremsstrahlung emission during $\\alpha$ decay?

    CERN Document Server

    Maydanyuk, Sergei P; Zou, Li-Ping

    2015-01-01

    We analyze if the nucleon structure of the $\\alpha$ decaying nucleus can be visible in the experimental bremsstrahlung spectra of the emitted photons which accompany such a decay. We develop a new formalism of the bremsstrahlung model taking into account distribution of nucleons in the $\\alpha$ decaying nuclear system. We conclude the following: (1) After inclusion of the nucleon structure into the model the calculated bremsstrahlung spectrum is changed very slowly for a majority of the $\\alpha$ decaying nuclei. However, we have observed that visible changes really exist for the $^{106}{\\rm Te}$ nucleus ($Q_{\\alpha}=4.29$ MeV, $T_{1/2}$=70 mks) even for the energy of the emitted photons up to 1 MeV. This nucleus is a good candidate for future experimental study of this task. (2) Inclusion of the nucleon structure into the model increases the bremsstrahlung probability of the emitted photons. (3) We find the following tendencies for obtaining the nuclei, which have bremsstrahlung spectra more sensitive to the ...

  3. Carbon emissions associated with forest fires in Brazil

    Energy Technology Data Exchange (ETDEWEB)

    Alencar, A.; Nepstad, D.; Moutinho, P. [Instituto de Pesquisa Ambiental da Amazonia, Belem, Para (Brazil)

    2005-07-01

    Forest fires or 'understory fires' that burn beneath forest canopies are one of the most important types of forest impoverishment in the Amazon causing large emissions of carbon to the atmosphere. The occurrence and the damage intensity of these fire events are related to the synergetic influence of selective logging, forest fragmentation and severe droughts especially such as that associated with El Nino Southern Oscillation (ENSO) episodes. In addition, forest fires occurrence also depends on landscape variables and forest structure. In this chapter we review the feedbacks that increase the susceptibility of the forest to understory fires, evaluate the impact of the fire events on forest biomass, analyze the spatial relationship of these forest fires with landscape characteristics for different regions along the arc of deforestation and estimate the area affected by forest fires in El Nino and non El Nino years. The results indicate that the area of forest burned by understory forest fire during the severe drought (ENSO) year (approximately 43.9 millions of hectares) was 13 times greater than the area burned during the average rainfall year (0.2 million hectares), and twice the area of annual deforestation. Our estimate of aboveground forest carbon that will eventually be released to the atmosphere through decomposition of dead trees due to understory fires in the Amazon arc of deforestation ranged from 0.024 to 0.165 Pg during the ENSO and from 0.001 to 0.011 Pg during the non ENSO years.

  4. Effect of dead carbon on the 14C dating of the speleothem

    Institute of Scientific and Technical Information of China (English)

    CAI Yanjun; Warren Beck; PENG Zicheng; ZHANG Zhaofeng

    2005-01-01

    Based on the comparison of dating results among high-precision TIMS U-series and AMS 14C as well as the published 14C dating results and their band counting ages (i.e. calendar ages), this paper discusses the effect of dead carbon on the speleothem 14C dating. The result shows that the fraction of incorporated dead carbon during the formation of speleothem varies. The change in the fraction of dead carbon would result in big deviation in the 14C age of the speleothem. It is indispensable to take the dead carbon into consideration when dating the speleothem using the 14C method or studying the atmospheric 14C concentration during the past with the speleothem.

  5. Institute a modest carbon tax to reduce carbon emissions, finance clean energy technology development, cut taxes, and reduce the deficit

    Energy Technology Data Exchange (ETDEWEB)

    Muro, Mark; Rothwell, Jonathan

    2012-11-15

    The nation should institute a modest carbon tax in order to help clean up the economy and stabilize the nation’s finances. Specifically, Congress and the president should implement a $20 per ton, steadily increasing carbon excise fee that would discourage carbon dioxide emissions while shifting taxation onto pollution, financing energy efficiency (EE) and clean technology development, and providing opportunities to cut taxes or reduce the deficit. The net effect of these policies would be to curb harmful carbon emissions, improve the nation’s balance sheet, and stimulate job-creation and economic renewal.

  6. Half-lives for proton emission, alpha decay, cluster radioactivity, and cold fission processes calculated in a unified theoretical framework

    Energy Technology Data Exchange (ETDEWEB)

    Duarte, S.B.; Tavares, O.A.P.; Guzman, F.; Dimarco, A. [Centro Brasileiro de Pesquisas Fisicas (CBPF), Rio de Janeiro, RJ (Brazil); Garcia, F. [Sao Paulo Univ., SP (Brazil). Inst. de Fisica; Universidade Estadual de Santa Cruz, Ilheus, BA (Brazil). Dept. de Ciencias Exatas e Tecnologicas; Rodriguez, O. [Sao Paulo Univ., SP (Brazil). Inst. de Fisica; Instituto Superior de Ciencias e Tecnologia Nucleares, La Habana (Cuba); Goncalves, M. [Instituto de Radioprotecao e Dosimetria (IRD), Rio de Janeiro, RJ (Brazil)

    2002-01-01

    Half-life values of spontaneous nuclear decay processes are presented in the framework of the Effective Liquid Drop Model (ELDM) using the combination of varying mass asymmetry shape description for the mass transfer with Werner-Wheeler's inertia coefficient V{sub MAS}/WW. The calculated half-lives of ground-state to ground-state transitions for the proton emission, alpha decay, cluster radioactivity, and cold fission processes are compared with experimental data. Results have shown that the ELDM is a very efficient model to describe these different decay processes in a same, unified theoretical framework. A Table listing the predicted half-life values, {tau}{sub c} is presented for all possible cases of spontaneous nuclear break-up such that -7.30 <{approx_equal} log{sub 10} {tau}{sub c} [S] <{approx_equal} 27.50 and log {sub 10}({tau}/{tau}{sub c}) > -17.0, where {tau} is the total half-life of the parent nucleus. (author)

  7. Coastal vegetation invasion increases greenhouse gas emission from wetland soils but also increases soil carbon accumulation

    International Nuclear Information System (INIS)

    Soil properties and soil–atmosphere fluxes of CO2, CH4 and N2O from four coastal wetlands were studied throughout the year, namely, native Kandelia obovata mangrove forest vs. exotic Sonneratia apetala mangrove forest, and native Cyperus malaccensis salt marsh vs. exotic Spartina alterniflora salt marsh. Soils of the four wetlands were all net sources of greenhouse gases while Sonneratia forest contributed the most with a total soil–atmosphere CO2-equivalent flux of 137.27 mg CO2 m−2 h−1, which is 69.23%, 99.75% and 44.56% higher than that of Kandelia, Cyperus and Spartina, respectively. The high underground biomass and distinctive root structure of Sonneratia might be responsible for its high greenhouse gas emission from the soil. Soils in Spartina marsh emitted the second largest amount of total greenhouse gases but it ranked first in emitting trace greenhouse gases. Annual average CH4 and N2O fluxes from Spartina soil were 13.77 and 1.14 μmol m−2 h−1, respectively, which are 2.08 and 1.46 times that of Kandelia, 1.03 and 1.15 times of Sonneratia, and 1.74 and 1.02 times of Cyperus, respectively. Spartina has longer growing season and higher productivity than native marshes which might increase greenhouse gas emission in cold seasons. Exotic wetland soils had higher carbon stock as compared to their respective native counterparts but their carbon stocks were offset by a larger proportion because of their higher greenhouse gas emissions. Annual total soil–atmosphere fluxes of greenhouse gases reduced soil carbon burial benefits by 8.1%, 9.5%, 6.4% and 7.2% for Kandelia, Sonneratia, Cyperus and Spartina, respectively, which narrowed down the gaps in net soil carbon stock between native and exotic wetlands. The results indicated that the invasion of exotic wetland plants might convert local coastal soils into a considerable atmospheric source of greenhouse gases although they at the same time increase soil carbon accumulation. - Highlights: • Soils

  8. Coastal vegetation invasion increases greenhouse gas emission from wetland soils but also increases soil carbon accumulation

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Yaping [Key Laboratory of the Ministry of Education for Coastal and Wetland Ecosystem, College of the Environment and Ecology, Xiamen University, Xiamen 361102, Fujian (China); Chen, Guangcheng [Third Institute of Oceanography, State Oceanic Administration, Xiamen 361005, Fujian (China); Ye, Yong, E-mail: yeyong.xmu@gmail.com [Key Laboratory of the Ministry of Education for Coastal and Wetland Ecosystem, College of the Environment and Ecology, Xiamen University, Xiamen 361102, Fujian (China)

    2015-09-01

    Soil properties and soil–atmosphere fluxes of CO{sub 2}, CH{sub 4} and N{sub 2}O from four coastal wetlands were studied throughout the year, namely, native Kandelia obovata mangrove forest vs. exotic Sonneratia apetala mangrove forest, and native Cyperus malaccensis salt marsh vs. exotic Spartina alterniflora salt marsh. Soils of the four wetlands were all net sources of greenhouse gases while Sonneratia forest contributed the most with a total soil–atmosphere CO{sub 2}-equivalent flux of 137.27 mg CO{sub 2} m{sup −2} h{sup −1}, which is 69.23%, 99.75% and 44.56% higher than that of Kandelia, Cyperus and Spartina, respectively. The high underground biomass and distinctive root structure of Sonneratia might be responsible for its high greenhouse gas emission from the soil. Soils in Spartina marsh emitted the second largest amount of total greenhouse gases but it ranked first in emitting trace greenhouse gases. Annual average CH{sub 4} and N{sub 2}O fluxes from Spartina soil were 13.77 and 1.14 μmol m{sup −2} h{sup −1}, respectively, which are 2.08 and 1.46 times that of Kandelia, 1.03 and 1.15 times of Sonneratia, and 1.74 and 1.02 times of Cyperus, respectively. Spartina has longer growing season and higher productivity than native marshes which might increase greenhouse gas emission in cold seasons. Exotic wetland soils had higher carbon stock as compared to their respective native counterparts but their carbon stocks were offset by a larger proportion because of their higher greenhouse gas emissions. Annual total soil–atmosphere fluxes of greenhouse gases reduced soil carbon burial benefits by 8.1%, 9.5%, 6.4% and 7.2% for Kandelia, Sonneratia, Cyperus and Spartina, respectively, which narrowed down the gaps in net soil carbon stock between native and exotic wetlands. The results indicated that the invasion of exotic wetland plants might convert local coastal soils into a considerable atmospheric source of greenhouse gases although they at the

  9. SIMULATION OF CARBON DIOXIDE EMISSIONS FROM DAIRY FARMS TO ASSESS GREENHOUSE GAS REDUCTION STRATEGIES

    Science.gov (United States)

    Farming practices can have a large impact on the soil carbon cycle and the resulting net emission of greenhouse gases including carbon dioxide (CO**2), methane and nitrous oxide. Primary sources of CO**2 emission on dairy farms are soil, plant, and animal respiration with smaller contributions from ...

  10. Effect of industrial fuel combustion on the carbon-14 level of atmospheric CO2

    International Nuclear Information System (INIS)

    As was previously noticed in 1953 by SUESS, the radiocarbon content of atmospheric CO2 was slightly lower in the 20th century (before the increase in the carbon-14 level due to the addition of artificial 14C) than at the time before the beginning of the industrial revolution in the 19th century. An exact knowledge of the magnitude of this effect is of interest in connection with the question of the rate of isotope exchange between atmospheric CO2 and the bicarbonates of the oceans. However, the radiocarbon level in the CO2 of the atmosphere is also subject to natural fluctuations caused by a variable cosmic-ray production rate of carbon-14. To investigate this the authors have cross-correlated sunspot numbers (as indicators of cosmic-ray activity) with the carbon-14 level in wood, and have detected a significant coherence between the two time series. The observed coherence permits an extrapolation of the natural carbon-14 values beyond the time of the beginning of artificial combustion of fossil fuel, around 1880. The results show that the observed small decrease in the carbon-14 level is somewhat affected by the increase of the production rate of carbon-14, as a consequence of relatively low solar activity during the preceding decades. The effect of industrial fuel combustion upon the carbon-14 level of the atmosphere can then be estimated for the Northern Hemisphere to be in the vicinity of -3%. (author)

  11. A Study on Life Cycle CO2 Emissions of Low-Carbon Building in South Korea

    Directory of Open Access Journals (Sweden)

    Su-Hyun Cho

    2016-06-01

    Full Text Available There have been much interest and many efforts to control global warming and reduce greenhouse gas (GHG emissions throughout the world. Recently, the Republic of Korea has also increased its GHG reduction goal and searched for an implementation plan. In buildings, for example, there have been technology developments and deployment policies to reduce GHG emissions from a life cycle perspective, covering construction materials, building construction, use of buildings and waste disposal. In particular, Korea’s Green Standard for Energy and Environmental Design is a certification of environmentally-friendly buildings for their energy saving and reduction of environmental pollution throughout their lives. In fact, the demand and adoption of the certification are rising every year. In construction materials and buildings, as a result, an environmentally-friendly aspect has become crucial. The importance of construction material and building development technologies that can reduce environmental load by diminishing GHG emissions in buildings has emerged. Moreover, there has been a rising necessity to verify the GHG reduction effects of buildings. To assess the reduction of carbon emissions in the buildings built with low-carbon construction technologies and materials, therefore, this study estimated life cycle carbon emissions in reference buildings in which general construction materials are used and in low-carbon buildings. For this, the carbon emissions and their reduction from construction materials (especially concrete between conventional products and low-carbon materials were estimated, using Life Cycle Assessment (LCA. After estimating carbon emissions from a building life cycle perspective, their reduction in low-carbon buildings compared to the reference buildings was reviewed. The results found that compared to conventional buildings, low-carbon buildings revealed a 25% decrease in carbon emissions in terms of the reduction of Life Cycle

  12. Achieving carbon emission reduction through industrial and urban symbiosis: A case of Kawasaki

    International Nuclear Information System (INIS)

    Industry and fossil fuel combustion are the main sources for urban carbon emissions. Most studies focus on energy consumption emission reduction and energy efficiency improvement. Material saving is also important for carbon emission reduction from a lifecycle perspective. IS (Industrial symbiosis) and UrS (urban symbiosis) have been effective since both of them encourage byproduct exchange. However, quantitative carbon emission reduction evaluation on applying them is still lacking. Consequently, the purpose of this paper is to fill such a gap through a case study in Kawasaki Eco-town, Japan. A hybrid LCA model was employed to evaluate to the lifecycle carbon footprint. The results show that lifecycle carbon footprints with and without IS and UrS were 26.66 Mt CO2e and 30.92 Mt CO2e, respectively. The carbon emission efficiency was improved by 13.77% with the implementation of IS and UrS. The carbon emission reduction was mainly from “iron and steel” industry, cement industry and “paper making” industry, with figures of 2.76 Mt CO2e, 1.16 Mt CO2e and 0.34 Mt CO2e, respectively. Reuse of scrape steel, blast furnace slag and waste paper are all effective measures for promoting carbon emission reductions. Finally, policy implications on how to further promote IS and UrS are presented. - Highlights: • We evaluate carbon emission reduction of industrial and urban symbiosis (IS/UrS). • Hybrid LCA model was used to evaluate lifecycle carbon footprint. • Carbon emission efficiency was improved by 13.77% after applying IS/UrS. • The importance of UrS in responding carbon reduction was addressed in the paper

  13. Energy consumption, carbon emissions and economic growth in Saudi Arabia: An aggregate and disaggregate analysis

    International Nuclear Information System (INIS)

    The objective of this study is to examine the relationship among economic growth, carbon emissions and energy consumption at the aggregate and disaggregate levels. For the aggregate energy consumption model, we use total energy consumption per capita and CO2 emissions per capita based on the total energy consumption. For the disaggregate analysis, we used oil, gas and electricity consumption models along with their respective CO2 emissions. The long-term income elasticities of carbon emissions in three of the four models are positive and higher than their estimated short-term income elasticities. These results suggest that carbon emissions increase with the increase in per capita income which supports the belief that there is a monotonically increasing relationship between per capita carbon emissions and per capita income for the aggregate model and for the oil and electricity consumption models. The long- and short-term income elasticities of carbon emissions are negative for the gas consumption model. This result indicates that if the Saudi Arabian economy switched from oil to gas consumption, then an increase in per capita income would reduce carbon emissions. The results also suggest that electricity is less polluting than other sources of energy. - Highlights: • Carbon emissions increase with the increase in per capita income in Saudi Arabia. • The income elasticity of CO2 is negative for the gas consumption model. • The income elasticity of CO2 is positive for the oil consumption model. • The results suggest that electricity is less polluting than oil and gas

  14. Carbon Emission from Forest Fires on Scots Pine Logging Sites in the Angara Region of Central Siberia

    Science.gov (United States)

    Ivanova, G. A.; Conard, S. G.; McRae, D. J.; Kukavskaya, E. A.; Bogorodskaya, A. V.; Kovaleva, N. M.

    2010-12-01

    Wildfire and large-scale forest harvesting are the two major disturbances in the Russian boreal forests. Non-recovered logged sites total about a million hectares in Siberia. Logged sites are characterized by higher fire hazard than forest sites due to the presence of generally untreated logging slash (i.e., available fuel) which dries out much more rapidly compared to understory fuels. Moreover, most logging sites can be easily accessed by local population; this increases the risk for fire ignition. Fire impacts on the overstory trees, subcanopy woody layer, and ground vegetation biomass were estimated on 14 logged and unlogged comparison sites in the Lower Angara Region in 2009-2010 as part of the NASA-funded NEESPI project, The Influence of Changing Forestry Practices on the Effects of Wildfire and on Interactions Between Fire and Changing Climate in Central Siberia. Based on calculated fuel consumption, we estimated carbon emission from fires on both logged and unlogged burned sites. Carbon emission from fires on logged sites appeared to be twice that on unlogged sites. Soil respiration decreased on both site types after fires. This reduction may partially offset fire-produced carbon emissions. Carbon emissions from fire and post-fire ecosystem damage on logged sites are expected to increase under changing climate conditions and as a result of anticipated increases in future forest harvesting in Siberia.

  15. Designing A Carbon Tax to Reduce U.S. Greenhouse Gas Emissions

    OpenAIRE

    Gilbert E. Metcalf

    2008-01-01

    This article describes a revenue and distributionally neutral approach to reducing U.S. greenhouse gas emissions that uses a carbon tax. The revenue from the carbon tax is used to finance an environmental earned income tax credit designed to be distributionally neutral. The credit is linked to earned income and helps offset the regressivity of the carbon tax. The carbon tax reform proposal is also revenue neutral and avoids conflating carbon policy with debates over the appropriate size of th...

  16. Challenges for Reducing Emissions of Black Carbon from the Transport Sector in Urban Areas

    Science.gov (United States)

    Zavala, M. A.; Molina, L. T.

    2013-05-01

    The transport sector is a large contributor of harmful gaseous and particulate emissions in many urban areas. Black carbon is a component of short-lived particulate matter emitted predominantly by freight, public transport, and heavy- duty trucks. Controlling the emissions of black carbon from the transport sector is important for mitigating its impacts on climate, ecosystems, and human health. However, reducing the emissions of black carbon from mobile sources may be a challenging task in many developing urban areas due to economic, social, and technical constrains. Several emissions control technologies offer a proven approach for reducing emissions of black carbon from diesel-powered mobile sources, but the accurate quantification of associated emissions benefits in developing urban areas is not well documented. We describe recent advances for the estimation of black carbon emissions from the transport sector in real world driving conditions and present examples of the potential benefits of implementing various emission control technologies in Mexico. The results can help in the identification of key factors that hinder the implementation of control emissions for reducing emissions of black carbon elsewhere.

  17. Joint Optimal Production Planning for Complex Supply Chains Constrained by Carbon Emission Abatement Policies

    Directory of Open Access Journals (Sweden)

    Longfei He

    2014-01-01

    Full Text Available We focus on the joint production planning of complex supply chains facing stochastic demands and being constrained by carbon emission reduction policies. We pick two typical carbon emission reduction policies to research how emission regulation influences the profit and carbon footprint of a typical supply chain. We use the input-output model to capture the interrelated demand link between an arbitrary pair of two nodes in scenarios without or with carbon emission constraints. We design optimization algorithm to obtain joint optimal production quantities combination for maximizing overall profit under regulatory policies, respectively. Furthermore, numerical studies by featuring exponentially distributed demand compare systemwide performances in various scenarios. We build the “carbon emission elasticity of profit (CEEP” index as a metric to evaluate the impact of regulatory policies on both chainwide emissions and profit. Our results manifest that by facilitating the mandatory emission cap in proper installation within the network one can balance well effective emission reduction and associated acceptable profit loss. The outcome that CEEP index when implementing Carbon emission tax is elastic implies that the scale of profit loss is greater than that of emission reduction, which shows that this policy is less effective than mandatory cap from industry standpoint at least.

  18. Arctic Black Carbon Initiative: Reducing Emissions of Black Carbon from Power & Industry in Russia

    Science.gov (United States)

    Cresko, J.; Hodson, E. L.; Cheng, M.; Fu, J. S.; Huang, K.; Storey, J.

    2012-12-01

    Deposition of black carbon (BC) on snow and ice is widely considered to have a climate warming effect by reducing the surface albedo and promoting snowmelt. Such positive climate feedbacks in the Arctic are especially problematic because rising surface temperatures may trigger the release of large Arctic stores of terrestrial carbon, further amplifying current warming trends. Recognizing the Arctic as a vulnerable region, the U.S. government committed funds in Copenhagen in 2009 for international cooperation targeting Arctic BC emissions reductions. As a result, the U.S. Department of State has funded three research and demonstration projects with the goal to better understand and mitigate BC deposition in the Russian Arctic from a range of sources. The U.S. Department of Energy's (DOE) Arctic BC initiative presented here is focused on mitigating BC emissions resulting from heat and power generation as well as industrial applications. A detailed understanding of BC sources and its transport and fate is required to prioritize efforts to reduce BC emissions from sources that deposit in the Russian Arctic. Sources of BC include the combustion of fossil fuels (e.g. coal, fuel oil, diesel) and the combustion of biomass (e.g. wildfires, agricultural burning, residential heating and cooking). Information on fuel use and associated emissions from the industrial and heat & power sectors in Russia is scarce and difficult to obtain from the open literature. Hence, our project includes a research component designed to locate Arctic BC emissions sources in Russia and determine associated BC transport patterns. We use results from the research phase to inform a subsequent assessment/demonstration phase. We use a back-trajectory modeling method (potential source contribution function - PSCF), which combines multi-year, high-frequency measurements with knowledge about atmospheric transport patterns. The PSCF modeling allows us to map the probability (by season and year) at course

  19. International Oil Price’s Impacts on Carbon Emission in China’s Transportation Industry

    Directory of Open Access Journals (Sweden)

    Guoxing Zhang

    2014-09-01

    Full Text Available Purpose: This paper analyses the impact mechanism of international oil price on the industrial carbon emission, and uses the partial least squares regression model to study international oil price’s impact on carbon emissions in China’s transportation industry.Design/methodology/approach: This paper chooses five independent variables of GDP, international oil price, private car population, passenger and freight transportation volume as impact factors to investigate industrial carbon emissions, the paper also analyses the impact mechanism of international oil price on the industrial carbon emission, and finally the paper uses the partial least squares regression model to study international oil price’s impact on carbon emissions in China’s transportation industry. With the independent variables’ historical data from 1994 to 2009 as a sample, the fitting of the industry carbon emissions is satisfying. And based on the data of 2011, the paper maintains the private car owning, passenger and freight transportation volume to study international oil prices’ impact on the industry carbon emissions at different levels of GDP.Findings: The results show that: with the same GDP growth, the industry carbon emissions increase with the rise in international oil prices, and vice versa, the industry carbon emissions decrease; and lastly when GDP increases to a certain extent, in both cases of international oil prices’ rise or fall, the industry carbon emissions will go up, and the industry carbon emissions increase even faster while the energy prices are rising.Practical implications: Limit the growth in private-vehicle ownership, change China's transport sector within the next short-term in the structure of energy consumption and put forward China's new energy, alternative energy sources and renewable energy application so as to weaken the dependence on international oil, and indirectly slowdown China's GDP growth rate, which are all possible

  20. Carbon dioxide emissions and nutrition on a drained pine mire - a case study

    Energy Technology Data Exchange (ETDEWEB)

    Hartman, M.; Karsisto, M.; Kaunisto, S. [Finnish Forest Research Inst., Vantaa (Finland). Vantaa Research Centre

    1996-12-31

    Drainage of boreal peatlands intensify aerobic decomposition and carbon dioxide emission from the peat substrate and increase tree growth. CO{sub 2} emission rates depend on the ground water level and the soil temperature. Predicted rises in mean air temperatures due to anthropogenically induced climate change are expected to further increase carbon dioxide emission from drained boreal peatlands. The role of added nutrients is somewhat vague. The purpose of this presentation is to give some preliminary results on microbial biomass carbon and on carbon dioxide output/input relationship on a pine mire. (6 refs.)

  1. Field Emission from Amorphous carbon Nitride Films Deposited on silicon Tip Arrays

    Institute of Scientific and Technical Information of China (English)

    李俊杰; 郑伟涛; 孙龙; 卞海蛟; 金曾孙; 赵海峰; 宋航; 孟松鹤; 赫晓东; 韩杰才

    2003-01-01

    Amorphous carbon nitride films (a-CNx) were deposited on silicon tip arrays by rf magnetron sputtering in pure nitrogen atmosphere. The field emission property of carbon nitride films on Si tips was compared with that of carbon nitride on silicon wafer. The results show that field emission property of carbon nitride films deposited on silicon tips can be improved significantly in contrast with that on wafer. It can be explained that field emission is sensitive to the local curvature and geometry, thus silicon tips can effectively promote field emission property of a-CNx films. In addition, the films deposited on silicon tips have a smaller effective work function ( F = 0.024 eV)of electron field emission than that on silicon wafer ( F = 0.060 e V), which indicates a significant enhancement of the ability of electron field emission from a-CNx films.

  2. Dependency of climate change and carbon cycle on CO2 emission pathways

    International Nuclear Information System (INIS)

    Previous research has indicated that the response of globally average temperature is approximately proportional to cumulative CO2 emissions, yet evidence of the robustness of this relationship over a range of CO2 emission pathways is lacking. To address this, we evaluate the dependency of climate and carbon cycle change on CO2 emission pathways using a fully coupled climate–carbon cycle model. We design five idealized pathways (including an overshoot scenario for cumulative emissions), each of which levels off to final cumulative emissions of 2000 GtC. The cumulative emissions of the overshoot scenario reach 4000 GtC temporarily, subsequently reducing to 2000 GtC as a result of continuous negative emissions. Although we find that responses of climatic variables and the carbon cycle are largely independent of emission pathways, a much weakened Atlantic meridional overturning circulation (AMOC) is projected in the overshoot scenario despite cessation of emissions. This weakened AMOC is enhanced by rapid warming in the Arctic region due to considerable temporary elevation of atmospheric CO2 concentration and induces the decline of surface air temperature and decrease of precipitation over the northern Atlantic and Europe region. Moreover, the weakened AMOC reduces CO2 uptake by the Atlantic and Arctic oceans. However, the weakened AMOC contributes little to the global carbon cycle. In conclusion, although climate variations have been found to be dependent on emission pathways, the global carbon cycle is relatively independent of these emission pathways, at least superficially. (letter)

  3. Carbon emission coefficient measurement of the coal-to-power energy chain in China

    International Nuclear Information System (INIS)

    Highlights: • CO2 emissions coefficient of the coal-energy chain in China is currently at 875 g/kW h−1. • The emission coefficient is a relatively low level compared with other countries. • CO2 is the main type of GHG emission and the most direct emission in the chain. • A great decline of potential energy use exists in the coal mining process of China compared with other countries. - Abstract: Coal-fired electricity generation has become the largest source of carbon emission in China. This study utilizes life-cycle assessment to assess the effect of carbon emissions and to calculate the coefficient of carbon emissions in coal-to-energy chains. Results show that the carbon emission coefficient of the coal-to-energy chain in China is 875 g/kW h−1, which is a relatively low level compared with that of other countries. CO2 is the main type of greenhouse gas emission and is the most abundant type of direct emission. China has to reduce electrical consumption in the coal-mining process to reduce carbon emissions in coal-to-energy chains. Moreover, China has to facilitate railway-line construction to improve the proportion of railway transportation to coal transportation

  4. Atmospheric monitoring for fugitive emissions from geological carbon storage

    Science.gov (United States)

    Loh, Z. M.; Etheridge, D.; Luhar, A.; Leuning, R.; Jenkins, C.

    2013-12-01

    We present a multi-year record of continuous atmospheric CO2 and CH4 concentration measurements, flask sampling (for CO2, CH4, N2O, δ13CO2 and SF6) and CO2 flux measurements at the CO2CRC Otway Project (http://www.co2crc.com.au/otway/), a demonstration site for geological storage of CO2 in south-western Victoria, Australia. The measurements are used to develop atmospheric methods for operational monitoring of large scale CO2 geological storage. Characterization of emission rates ideally requires concentration measurements upwind and downwind of the source, along with knowledge of the atmospheric turbulence field. Because only a single measurement location was available for much of the measurement period, we develop techniques to filter the record and to construct a ';pseudo-upwind' measurement from our dataset. Carbon dioxide and methane concentrations were filtered based on wind direction, downward shortwave radiation, atmospheric stability and hour-to-hour changes in CO2 flux. These criteria remove periods of naturally high concentration due to the combined effects of biogenic respiration, stable atmospheric conditions and pre-existing sources (both natural and anthropogenic), leaving a reduced data set, from which a fugitive leak from the storage reservoir, the ';(potential) source sector)', could more easily be detected. Histograms of the filtered data give a measure of the background variability in both CO2 and CH4. Comparison of the ';pseudo-upwind' dataset histogram with the ';(potential) source sector' histogram shows no statistical difference, placing limits on leakage to the atmosphere over the preceding two years. For five months in 2011, we ran a true pair of up and downwind CO2 and CH4 concentration measurements. During this period, known rates of gas were periodically released at the surface (near the original injection point). These emissions are clearly detected as elevated concentrations of CO2 and CH4 in the filtered data and in the measured

  5. Proportion of biogenic carbon in flue gas by carbon-14 measurement

    International Nuclear Information System (INIS)

    The subject of this project is closely related to EU's emissions trading system and to the current and future monitoring needs therein. The determination of fossil part of emissions originated from various fuels by stack measurements or by laboratory analyses could possibly find users also in other fields outside the ETS (e.g. waste incineration). After the market analysis and preliminary measurements carried out in the previous Biocarbon project this project focused on the development of the sampling method for stack measurements and to the validation of isotope measurements. The results obtained for fossil proportion of the fuel by current methods will be compared to those obtained by isotope measurements. The operation of the sampling system was tested in long period tests in plant conditions. Moreover, the sample preparation methods and isotope measurements were validated by measuring the proportions of biogenic and fossil carbon of known traffic fuel mixtures. The developed service concept can also be utilised as a fraud prevention measure related to the expanding international biofuels-trade. (orig.)

  6. Impact of direct greenhouse gas emissions on the carbon footprint of water reclamation processes employing nitrification–denitrification

    Energy Technology Data Exchange (ETDEWEB)

    Schneider, Andrew G., E-mail: andrew.schneider@yale.edu [University of Cincinnati, Department of Geology, Cincinnati, OH 45221 (United States); Townsend-Small, Amy [University of Cincinnati, Department of Geology, Cincinnati, OH 45221 (United States); University of Cincinnati, Department of Geography, Cincinnati, OH 45221 (United States); Rosso, Diego [Department of Civil and Environmental Engineering, University of California, Irvine, CA 92697-2175 (United States)

    2015-02-01

    Water reclamation has the potential to reduce water supply demands from aquifers and more energy-intensive water production methods (e.g., seawater desalination). However, water reclamation via biological nitrification–denitrification is also associated with the direct emission of the greenhouse gases (GHGs) CO{sub 2}, N{sub 2}O, and CH{sub 4}. We quantified these direct emissions from the nitrification–denitrification reactors of a water reclamation plant in Southern California, and measured the {sup 14}C content of the CO{sub 2} to distinguish between short- and long-lived carbon. The total emissions were 1.5 (± 0.2) g-fossil CO{sub 2} m{sup −3} of wastewater treated, 0.5 (± 0.1) g-CO{sub 2}-eq of CH{sub 4} m{sup −3}, and 1.8 (± 0.5) g-CO{sub 2}-eq of N{sub 2}O m{sup −3}, for a total of 3.9 (± 0.5) g-CO{sub 2}-eq m{sup −3}. This demonstrated that water reclamation can be a source of GHGs from long lived carbon, and thus a candidate for GHG reduction credit. From the {sup 14}C measurements, we found that between 11.4% and 15.1% of the CO{sub 2} directly emitted was derived from fossil sources, which challenges past assumptions that the direct CO{sub 2} emissions from water reclamation contain only modern carbon. A comparison of our direct emission measurements with estimates of indirect emissions from several water production methods, however, showed that the direct emissions from water reclamation constitute only a small fraction of the plant's total GHG footprint. - Highlights: • Direct greenhouse gas emissions were measured at a wastewater reclamation plant. • These greenhouse gas emissions amounted to 3.9 (± 0.5) g-CO{sub 2}-eq m{sup −3} of wastewater. • {sup 14}C analysis of the CO{sub 2} emissions was conducted to determine the fossil component. • 11.4% to 15.1% of the emitted CO{sub 2} was derived from fossil sources.

  7. Impact of direct greenhouse gas emissions on the carbon footprint of water reclamation processes employing nitrification–denitrification

    International Nuclear Information System (INIS)

    Water reclamation has the potential to reduce water supply demands from aquifers and more energy-intensive water production methods (e.g., seawater desalination). However, water reclamation via biological nitrification–denitrification is also associated with the direct emission of the greenhouse gases (GHGs) CO2, N2O, and CH4. We quantified these direct emissions from the nitrification–denitrification reactors of a water reclamation plant in Southern California, and measured the 14C content of the CO2 to distinguish between short- and long-lived carbon. The total emissions were 1.5 (± 0.2) g-fossil CO2 m−3 of wastewater treated, 0.5 (± 0.1) g-CO2-eq of CH4 m−3, and 1.8 (± 0.5) g-CO2-eq of N2O m−3, for a total of 3.9 (± 0.5) g-CO2-eq m−3. This demonstrated that water reclamation can be a source of GHGs from long lived carbon, and thus a candidate for GHG reduction credit. From the 14C measurements, we found that between 11.4% and 15.1% of the CO2 directly emitted was derived from fossil sources, which challenges past assumptions that the direct CO2 emissions from water reclamation contain only modern carbon. A comparison of our direct emission measurements with estimates of indirect emissions from several water production methods, however, showed that the direct emissions from water reclamation constitute only a small fraction of the plant's total GHG footprint. - Highlights: • Direct greenhouse gas emissions were measured at a wastewater reclamation plant. • These greenhouse gas emissions amounted to 3.9 (± 0.5) g-CO2-eq m−3 of wastewater. • 14C analysis of the CO2 emissions was conducted to determine the fossil component. • 11.4% to 15.1% of the emitted CO2 was derived from fossil sources

  8. A review of activated carbon technologies for reducing MSW incinerator emissions

    International Nuclear Information System (INIS)

    Though activated carbon is, by no means, a newcomer to the pollution control field, having been used as a water purifier and more recently demonstrated as a flue gas cleaner on power plants, it is now attracting considerable attention in Europe as a means to reduce further the quantity of toxic organic and metal emissions from new and existing municipal waste combustors. Since activated carbon is a potentially important future emissions control technology for MWCs in the US, particularly for removal of mercury and dioxin, this paper discusses the impetus which has motivated the experimentation with various activated carbon technologies which is now taking place, will describe how some of the activated carbon systems (e.g., post-emissions control fixed carbon bed and injection of carbon with scrubber reagent) being tested now function and where they fit in existing pollution control trains, and will present available performance data and emissions reductions actually achieved for each system

  9. PS1-14bj: A Hydrogen-Poor Superluminous Supernova With a Long Rise and Slow Decay

    CERN Document Server

    Lunnan, R; Berger, E; Milisavljevic, D; Jones, D O; Rest, A; Fong, W; Fransson, C; Margutti, R; Drout, M R; Blanchard, P K; Challis, P; Cowperthwaite, P S; Foley, R J; Kirshner, R P; Morell, N; Riess, A G; Roth, K C; Scolnic, D; Smartt, S J; Smith, K W; Villar, V A; Chambers, K C; Draper, P W; Huber, M E; Kaiser, N; Kudritzki, R -P; Magnier, E A; Metcalfe, N; Waters, C

    2016-01-01

    We present photometry and spectroscopy of PS1-14bj, a hydrogen-poor superluminous supernova (SLSN) at redshift $z=0.5215$ discovered in the last months of the Pan-STARRS1 Medium Deep Survey. PS1-14bj stands out by its extremely slow evolution, with an observed rise to maximum light $\\gtrsim 125$ days in the rest frame, and exponential decline out to $\\sim 250$ days past peak at a measured rate of $9.75\\times 10^{-3}$ mag day$^{-1}$, consistent with fully-trapped $^{56}$Co decay. This is the longest rise time measured in a SLSN to date, and the first SLSN to show a rise time consistent with pair-instability supernova (PISN) models. Compared to other slowly-evolving SLSNe, it is spectroscopically similar to the prototype SN 2007bi at maximum light, though somewhat lower in luminosity ($L_{\\rm peak} \\simeq 4.4 \\times 10^{43}~{\\rm erg~s}^{-1}$) and with a flatter peak than previous events. In addition to its slow evolution, PS1-14bj shows a number of peculiar properties, including a near-constant color temperatur...

  10. Phenomenological Study of W′ Boson Decaying to Muon and Missing Transverse Energy at 14 TeV

    International Nuclear Information System (INIS)

    Many possible extensions of the Standard Model (SM) are predicted by theories. A possible abstracted extension of the SM is the so-called Sequentail Standard Model (SSM). The SSM model predicts signature of new charged gauge boson W′. In this paper, the discovery potential of new heavy charged gauge boson (W′) decaying to a muon and a neutrino at center of mass energy 14 TeV has been studied. An assumption has been made that the early data of the second run of the Large Hadron Collider (LHC) correspond to an integrated luminosity of 300 fb-1. The Monte Carlo (MC) signal samples are generated with the multipurpose event generator Pythia 6, while the background samples are generated with the matrix element generator Mad Graph 5 followed by hadronization and parton showering by using Pythia 8 and then we used Delphes for fast detector simulation

  11. Finite-time deviations from exponential decay in the Weisskopf-Wigner model of spontaneous emission

    International Nuclear Information System (INIS)

    For the first time to the authors' knowledge, a mathematically rigorous method is used for treating finite-time deviations from the exponential decay in the case of spontaneous Lyman-α transition in a two-level hydrogenic atom. In the so-called Weisskopf-Wigner model (where the rotating-wave approximation is implied), finite-time deviations with a rigorous validity range, based on accurate error estimations, are derived. (orig.)

  12. Modelling accidental releases of carbon 14 in the environment: application as an excel spreadsheet

    International Nuclear Information System (INIS)

    An application as an Excel spreadsheet of the simplified modelling approach of carbon 14 transfer in the environment developed by Tamponnet (2002) is presented. Based on the use of growth models of biological systems (plants, animals, etc.), the one-pool model (organic carbon) that was developed estimates the concentration of carbon 14 within the different compartments of the food chain and in fine the dose to man by ingestion in the case of a chronic or accidental release of carbon 14 in a river or the atmosphere. Data and knowledge have been implemented on Excel using the object-oriented programming language VisualBasic (Microsoft Visual Basic 6.0). The structure of the conceptual model and the Excel sheet are first briefly exposed. A numerical application of the model under a scenario of an accidental release of carbon 14 in the atmosphere is then presented. Simulation results and perspectives are discussed. (author)

  13. High-resolution forest carbon stocks and emissions in the Amazon

    OpenAIRE

    Gregory P. Asner; Powell, George V. N.; Mascaro, Joseph; Knapp, David E; Clark, John K.; Jacobson, James; Kennedy-Bowdoin, Ty; Balaji, Aravindh; Paez-Acosta, Guayana; Victoria, Eloy; Secada, Laura; Valqui, Michael; Hughes, R. Flint

    2010-01-01

    Efforts to mitigate climate change through the Reduced Emissions from Deforestation and Degradation (REDD) depend on mapping and monitoring of tropical forest carbon stocks and emissions over large geographic areas. With a new integrated use of satellite imaging, airborne light detection and ranging, and field plots, we mapped aboveground carbon stocks and emissions at 0.1-ha resolution over 4.3 million ha of the Peruvian Amazon, an area twice that of all forests in Costa Rica, to reveal the ...

  14. China's carbon emissions from urban and rural households during 1992-2007

    OpenAIRE

    Lan-Cui Liu; Gang Wu; Jin-Nan Wang; Yi-Ming Wei

    2010-01-01

    In China, Rapid economic growth has stimulated fast urban expansion and rural household income and consumption expenditure. In current paper, an input-output method is used to determine the impact of China's increased urban and rural household consumption on carbon emissions. The results shows that the direct and indirect CO2 emission from household consumption accounted for more than 40% of total carbon emissions from primary energy utilization in China in 1992-2007. The population increase,...

  15. National trajectories of carbon emissions: analysis of proposals to foster the transition to low-carbon economies

    International Nuclear Information System (INIS)

    In this paper we develop a framework for analyzing carbon dioxide (CO2) emissions trajectories from the energy and industrial sectors of the world's nations under various policy options. A robust conclusion of our analysis is that early action by both developed and developing nations will be required to hold atmospheric CO2 at or below doubled pre-industrial levels and incentives for renewed investments in energy-sector technologies are a required component of early action. We therefore develop and examine an international emissions regime that: (a) in the short-term 'jump starts' the political and project-implementation process by providing incentives to exploit profitable or low-cost carbon reduction opportunities; (b) in the near- and medium-term addresses the inequities resulting from historic imbalances in greenhouse-gas emissions while promoting efficient pathways for carbon reduction; and (c) in the long-term recognizes the equal rights of individuals to exploit the services of the atmosphere and pursue a reasonable standard of living in a low-carbon economy. We present and analyze a proposal to promote near-term activity in carbon reduction and energy innovation through a revitalized program of international joint implementation (JI) projects for carbon emissions reduction or carbon sequestration projects. Under our proposal, JI partner nations both receive full credit for carbon reductions that can be 'banked' and applied at a later date toward national emissions quotas in the climate convention. A finite program lifetime provides further impetus counting' of credits results in only modest additional cumulative carbon emissions relative to a similar scenario without cooperative partnerships. This 'JI banking' plan promotes critically needed scientific and institutional experience and innovation, initiates cost-effective carbon reductions, and provides vital national flexibility in meeting eventual targets. (author)

  16. Toward Efficient Orange Emissive Carbon Nanodots through Conjugated sp(2) -Domain Controlling and Surface Charges Engineering.

    Science.gov (United States)

    Qu, Songnan; Zhou, Ding; Li, Di; Ji, Wenyu; Jing, Pengtao; Han, Dong; Liu, Lei; Zeng, Haibo; Shen, Dezhen

    2016-05-01

    A strategy of achieving efficient orange emissive carbon nanodots (CNDs) with large sized conjugated sp(2) -domain is achieved in a solvothermal synthetic route using dimethylformamide as solvent, which is the basis of orange bandgap emission; enhanced orange emission with photoluminescent quantum yield of 46% is realized through surface charges engineering by surface metal-cation-functionalization. PMID:26919550

  17. Black and organic carbon emission inventories: review and application to California.

    Science.gov (United States)

    Chow, Judith C; Watson, John G; Lowenthal, Douglas H; Chen, Lung-Wen Antony; Motallebi, Nehzat

    2010-04-01

    Particulate black or elemental carbon (EC) (black carbon [BC]) and organic carbon (OC) affect climate, visibility, and human health. Several "top-down" and "bottom-up" global emission inventories for these components have compiled country-wide emission factors, source profiles, and activity levels that do not necessarily reflect local conditions. Recent estimates of global BC and OC emissions range from 8 to 24 and 33 to 62 Tg (1012 g) per year, respectively. U.S. BC emissions account for 5.6% of the global total emissions. Uncertainties in global BC emission estimates are a factor of 2 or more. The U.S. National Emissions Inventory is well documented, but its major source categories are not easily related to EC- and OC-emitting source subcategories. California's bottom-up emission inventory is easily accessible at many levels of detail and provides an example of how sources can be regrouped for speciated emission rates. PM2.5 (particulate matter with aerodynamic diameters burning. Major discrepancies were found for directly emitted OC, with the global inventory estimating more than twice that of the California inventory. Most of the discrepancy was due to differences in open biomass burning (wildfires and agricultural waste) for which carbon emissions are highly variable. BC and OC emissions are sensitive to the availability and variability of existing source profiles, and profiles more specific to fuels and operating conditions are needed to increase emission accuracy. PMID:20437785

  18. Urban energy consumption and related carbon emission estimation: a study at the sector scale

    Science.gov (United States)

    Lu, Weiwei; Chen, Chen; Su, Meirong; Chen, Bin; Cai, Yanpeng; Xing, Tao

    2013-12-01

    With rapid economic development and energy consumption growth, China has become the largest energy consumer in the world. Impelled by extensive international concern, there is an urgent need to analyze the characteristics of energy consumption and related carbon emission, with the objective of saving energy, reducing carbon emission, and lessening environmental impact. Focusing on urban ecosystems, the biggest energy consumer, a method for estimating energy consumption and related carbon emission was established at the urban sector scale in this paper. Based on data for 1996-2010, the proposed method was applied to Beijing in a case study to analyze the consumption of different energy resources (i.e., coal, oil, gas, and electricity) and related carbon emission in different sectors (i.e., agriculture, industry, construction, transportation, household, and service sectors). The results showed that coal and oil contributed most to energy consumption and carbon emission among different energy resources during the study period, while the industrial sector consumed the most energy and emitted the most carbon among different sectors. Suggestions were put forward for energy conservation and emission reduction in Beijing. The analysis of energy consumption and related carbon emission at the sector scale is helpful for practical energy saving and emission reduction in urban ecosystems.

  19. The impacts of population change on carbon emissions in China during 1978–2008

    International Nuclear Information System (INIS)

    This study examines the impacts of population size, population structure, and consumption level on carbon emissions in China from 1978 to 2008. To this end, we expanded the stochastic impacts by regression on population, affluence, and technology model and used the ridge regression method, which overcomes the negative influences of multicollinearity among independent variables under acceptable bias. Results reveal that changes in consumption level and population structure were the major impact factors, not changes in population size. Consumption level and carbon emissions were highly correlated. In terms of population structure, urbanization, population age, and household size had distinct effects on carbon emissions. Urbanization increased carbon emissions, while the effect of age acted primarily through the expansion of the labor force and consequent overall economic growth. Shrinking household size increased residential consumption, resulting in higher carbon emissions. Households, rather than individuals, are a more reasonable explanation for the demographic impact on carbon emissions. Potential social policies for low carbon development are also discussed. - Highlights: ► We examine the impacts of population change on carbon emissions in China. ► We expand the STIRPAT model by containing population structure factors in the model. ► The population structure includes age structure, urbanization level, and household size. ► The ridge regression method is used to estimate the model with multicollinearity. ► The population structure plays a more important role compared with the population size.

  20. The impacts of population change on carbon emissions in China during 1978-2008

    Energy Technology Data Exchange (ETDEWEB)

    Zhu Qin, E-mail: zhuqin@fudan.edu.cn; Peng Xizhe, E-mail: xzpeng@fudan.edu.cn

    2012-09-15

    This study examines the impacts of population size, population structure, and consumption level on carbon emissions in China from 1978 to 2008. To this end, we expanded the stochastic impacts by regression on population, affluence, and technology model and used the ridge regression method, which overcomes the negative influences of multicollinearity among independent variables under acceptable bias. Results reveal that changes in consumption level and population structure were the major impact factors, not changes in population size. Consumption level and carbon emissions were highly correlated. In terms of population structure, urbanization, population age, and household size had distinct effects on carbon emissions. Urbanization increased carbon emissions, while the effect of age acted primarily through the expansion of the labor force and consequent overall economic growth. Shrinking household size increased residential consumption, resulting in higher carbon emissions. Households, rather than individuals, are a more reasonable explanation for the demographic impact on carbon emissions. Potential social policies for low carbon development are also discussed. - Highlights: Black-Right-Pointing-Pointer We examine the impacts of population change on carbon emissions in China. Black-Right-Pointing-Pointer We expand the STIRPAT model by containing population structure factors in the model. Black-Right-Pointing-Pointer The population structure includes age structure, urbanization level, and household size. Black-Right-Pointing-Pointer The ridge regression method is used to estimate the model with multicollinearity. Black-Right-Pointing-Pointer The population structure plays a more important role compared with the population size.