WorldWideScience

Sample records for carbon 10

  1. Annual carbon balance of a peatland 10 yr following restoration

    Directory of Open Access Journals (Sweden)

    M. Strack

    2013-05-01

    Full Text Available Undisturbed peatlands represent long-term net sinks of carbon; however, peat extraction converts these systems into large and persistent sources of greenhouse gases. Although rewetting and restoration following peat extraction have taken place over the last several decades, very few studies have investigated the longer term impact of this restoration on peatland carbon balance. We determined the annual carbon balance of a former horticulturally-extracted peatland restored 10 yr prior to the study and compared these values to the carbon balance measured at neighboring unrestored and natural sites. Carbon dioxide (CO2 and methane (CH4 fluxes were measured using the chamber technique biweekly during the growing season from May to October 2010 and three times over the winter period. Dissolved organic carbon (DOC export was measured from remnant ditches in the unrestored and restored sites. During the growing season the restored site had greater uptake of CO2 than the natural site when photon flux density was greater than 1000 μmol m−2 s−1, while the unrestored site remained a source of CO2. Ecosystem respiration was similar between natural and restored sites, which were both significantly lower than the unrestored site. Methane flux remained low at the restored site except from open water pools, created as part of restoration, and remnant ditches. Export of DOC during the growing season was 5.0 and 28.8 g m−2 from the restored and unrestored sites, respectively. Due to dry conditions during the study year all sites acted as net carbon sources with annual balance of the natural, restored and unrestored sites of 250.7, 148.0 and 546.6 g C m−2, respectively. Although hydrological conditions and vegetation community at the restored site remained intermediate between natural and unrestored conditions, peatland restoration resulted in a large reduction in annual carbon loss from the system resulting in a carbon balance more similar to a natural

  2. 2002 Monthly Carbon Dioxide Emissions from Mexico at a 10x10k Spatial Resolution

    Science.gov (United States)

    Mendoza, D. L.; Gurney, K. R.; Geethakumar, S.; Zhou, Y.; Sahni, N.

    2009-12-01

    The contribution of fossil fuel CO2 emissions to the total measured amount of CO2 in the Earth’s atmosphere remains an important component of carbon cycle science, particularly as efforts to understand the net exchange of carbon at the surface move to smaller scales. In order to reduce the uncertainty of this flux, researchers led by Purdue University have built a high-resolution fossil fuel CO2 flux inventory for the United States, called “Vulcan”. The Vulcan inventory quantifies emissions for the United States at 10km resolution every hour for the year 2002 and can be seen as a key component of a national assessment and verification system for greenhouse gas emissions and emissions mitigation. As part of the North American Carbon Project, the 2002 carbon dioxide emissions from Mexico are presented at the monthly temporal and municipality spatial scale. Mexico is of particular importance because of the scientific integration under the North American Carbon Program. Furthermore, Mexico has seen a notable growth in its population as well as migration toward urban centers and increasing energy requirements due in part to industrial intensification. The native resolution of the emissions is geolocated (lat/lon) for point sources, such as power plants, airports, and large industry. The emissions are estimated at the municipality level for residential and commercial sources, and allocated to roads for the mobile transport sector. Data sources include the National Emissions Inventory (NEI), Commission for Environmental Cooperation (CEC), and Carbon Monitoring for Action (CARMA). CO2 emissions are calculated from the 1999 NEI data by converting CO emissions using sector and process-dependent emission factors, and is scaled up to 2002 using statistics obtained from the Carbon Dioxide Information Analysis Center CDIAC. CEC and CARMA data, which encompass power plant emissions, are already in units of CO2. Emissions are regridded to 10x10k and 0.1x0.1 deg grids to

  3. 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

  4. Effect of carbon content on the mechanical properties of 10Cr-5W ferritic steels

    International Nuclear Information System (INIS)

    The effect of carbon content on the microstructures, the tensile strength, creep strength and fracture toughness of 10Cr-5W ferritic steels containing from 0.02 to 0.13 mass% C is investigated. The low carbon steels possess the higher Ms temperature than the high carbon steels, so that the packet size of the martensite structure is larger in the low carbon steels. Both the FATT (fracture appearance transition temperature) and the USE (upper shelf energy) increase with decreasing carbon content. This means the decrease of toughness and the increase of ductility with decreasing carbon content. Fine precipitates of the Laves phase are observed in the martensite lath in all experimental steels after quality heat treatment. The tensile strength measured at 873 K has a tendency to increase with decreasing C content. But a certain amount of C is needed even in 5 W ferritic steels to keep the longer creep-rupture life under the lower stress level. (orig.)

  5. Gorsky effect and diffusion of carbon in grade VT1-0 titanium

    International Nuclear Information System (INIS)

    By means of transmitting electron microscopy one showed the presence of metastable phase formations on the basis of carbon related coherently to matrix in VT1-0 titanium. Within 300-550 deg C temperature range when conducting three-point bending testings one observe the Gorsky effect by carbon determined at reverse deformation of creep. One justified the techniques enabling to determine diffusion coefficient of intrusion impurity causing the Gorsky effect. Using that technique one determined the diffusion efficient coefficients of carbon within 300-550 deg C range in VT1-0 specimens with grain various size. It is shown that in the ultrafinely-grain state (grain size is about 0.3 μm) the grain-boundary diffusion is the basic mechanism of carbon diffusion. One determined activation energy values of grain-boundary and volume diffusion of carbon equal to 103 and 177 kJ/mole

  6. Secondary organic carbon quantification and source apportionment of PM10 in Kaifeng, China

    Institute of Scientific and Technical Information of China (English)

    WU Lin; FENG Yinchang; WU Jianhui; ZHU Tan; BI Xiaohui; HAN Bo; YANG Weihong; YANG Zhiqiang

    2009-01-01

    During 2005, the filter samples of ambient PM10 from five sites and the source samples of particulate matter were collected in Kaifeng, Henan province of China. Nineteen elements, water-soluble ions, total carbon (TC) and organic carbon (OC) contained in samples were analyzed. Seven contributive source types were identified and their contributions to ambient PM10 were estimated by chemical mass balance (CMB) receptor model. Weak associations between the concentrations of organic carbon and element carbon (EC) were observed during the sampling periods, indicating that there was secondary organic aerosol pollution in the urban atmosphere. An indirect method of "OC/EC minimum ratio" was applied to estimate the concentration of secondary organic carbon (SOC). The results showed that SOC contributed 26.2%, 32.4% and 18.0% of TC in spring, summer-fall and winter respectively, and the annual average SOC concentration was 7.07 μg/m3, accounting for 5.73% of the total mass in ambient PM10. The carbon species concentrations in ambient PM10 were recalculated by subtracting the SOC concentrations from measured concentrations of TC and OC to increase the compatibility of source and receptor measurements for CMB model.

  7. Zn-10.2% Fe coating over carbon steel atmospheric corrosion resistance. Comparison with zinc coating

    International Nuclear Information System (INIS)

    Zn-10.2% Fe galvanized coating versus hot galvanized coating over carbon steel corrosion performance has been studied. Different periods of atmospheric exposures in various Valencia Community sites, and salt spray accelerated test have been done. Carbon steel test samples have been used simultaneously in order to classify exposure atmosphere corrosivity, and environmental exposure atmosphere characteristics have been analyzed. Corrosion Velocity versus environmental parameters has been obtained. (Author) 17 refs

  8. Carbon-10: Example of cyclotron production of positron emitters as an open research field

    DEFF Research Database (Denmark)

    Alves, F.; Lima, J.J.P.; Nickles, R.J.;

    2007-01-01

    This paper supports the thesis that significant improvement of PET output response to clinical questions can be achieved by innovation in radionuclide production. Moreover, that development can be performed with the resources available at a clinical centre. Carbon-10 production parameters studies...

  9. Resonant Enhancement of Coherent Phonons in Carbon Nanotubes Observed with Sub-10fs Time Resolution

    Directory of Open Access Journals (Sweden)

    Yanagi K.

    2013-03-01

    Full Text Available Using wavelength-resolved pump-probe spectroscopy with a sub-10-fs laser, we investigated resonant enhancement of radial breathing mode and G-mode coherent phonons in carbon nanotubes (CNTs, and successfully distinguished the electronic states of CNTs with different chiralities.

  10. Carbon-10: Example of cyclotron production of positron emitters as an open research field

    International Nuclear Information System (INIS)

    This paper supports the thesis that significant improvement of PET output response to clinical questions can be achieved by innovation in radionuclide production. Moreover, that development can be performed with the resources available at a clinical centre. Carbon-10 production parameters studies are used as example. A technical methodology for measurement of excitation function of nuclear reactions yielding short-lived radionuclides, performed to measure cross section values of the 10B(p,n)10C reaction in a PET-devoted cyclotron, is presented

  11. Current density profile and electron beam localization measurements using carbon pellets on T-10

    International Nuclear Information System (INIS)

    The letter presents experimental evidence and an analysis of two phenomena arising during carbon pellet ablation - a toroidal trajectory deflection and enhanced localized ablation in the electron cyclotron resonance (ECR) current drive regime. A model developed for describing the toroidal deflection of a carbon pellet in a tokamak shows that the trajectory curvature is sensitive to the current density. Photography of the pellet trajectory is used as a diagnostic for the determination of the local current density in an ohmically heated plasma. Directly measured current profiles using pellets are in reasonable agreement with that obtained using the Spitzer conductivity, and current density fluctuations have been observed that are probably associated with magnetic islands. It is shown that in the ECR current drive regime on T-10, energetic electrons probably stimulated by the microwave power are located in a narrow zone (2 cm thickness in the radial direction) with sharp boundaries. (author). Letter-to-the-editor. 7 refs, 5 figs

  12. LETTER: Current density profile and electron beam localization measurements using carbon pellets on T-10

    Science.gov (United States)

    Egorov, S. M.; Kuteev, B. V.; Miroshnikov, I. V.; Mikhailenko, A. A.; Sergeev, V. Yu.; Ushakov, S. N.; Bagdasarov, A. A.; Chistyakov, V. V.; Elizavetin, D. Yu.; Vasin, N. L.

    1992-11-01

    The authors present experimental evidence and an analysis of two phenomena arising during carbon pellet ablation-a toroidal trajectory deflection and enhanced localized ablation in the electron cyclotron resonance (ECR) current drive regime. A model developed for describing the toroidal deflection of a carbon pellet in a tokamak shows that the trajectory curvature is sensitive to the current density. Photography of the pellet trajectory is used as a diagnostic for the determination of the local current density in an ohmically heated plasma. Directly measured current profiles using pellets are in reasonable agreement with that obtained using the Spitzer conductivity, and current density fluctuations have been observed that are probably associated with magnetic islands. It is shown that in the ECR current drive regime on T-10, energetic electrons probably stimulated by the microwave power are located in a narrow zone (2 cm thickness in the radial direction) with sharp boundaries

  13. Including an ocean carbon cycle model into iLOVECLIM (v1.0)

    OpenAIRE

    N. Bouttes; Roche, D. M.; V. Mariotti; L. Bopp

    2015-01-01

    The atmospheric carbon dioxide concentration plays a crucial role in the radiative balance and as such has a strong influence on the evolution of climate. Because of the numerous interactions between climate and the carbon cycle, it is necessary to include a model of the carbon cycle within a climate model to understand and simulate past and future changes of the carbon cycle. In particular, natural variations of atmospheric CO2 have happened in the past, while anthropogenic...

  14. Including an ocean carbon cycle model into iLOVECLIM (v1.0)

    OpenAIRE

    N. Bouttes; Roche, D. M.; V. Mariotti; L. Bopp

    2015-01-01

    The atmospheric carbon dioxide concentration plays a crucial role in the radiative balance and as such has a strong influence on the evolution of climate. Because of the numerous interactions between climate and the carbon cycle, it is necessary to include a model of the carbon cycle within a climate model to understand and simulate past and future changes of the carbon cycle. In particular, natural variations of atmospheric CO2 have happened in the past, while anthropogenic...

  15. Homogeneous water nucleation and droplet growth in methane and carbon dioxide mixtures at 235 K and 10 bar.

    Science.gov (United States)

    Holten, V; van Dongen, M E H

    2010-05-28

    Homogeneous nucleation rates and droplet growth rates of water in pure methane and mixtures of methane and carbon dioxide were measured in an expansion wave tube at 235 K and 10 bar. The nucleation rate in pure methane is three orders of magnitude higher than literature nucleation rates of water in low-pressure helium or argon. Addition of carbon dioxide to the carrier gas mixture increases the rates even more. Specifically, rates in a mixture of methane and 3% carbon dioxide are a factor of 10 higher than the rates in pure methane. With 25% carbon dioxide, the rates are four orders of magnitude higher than the rates in pure methane. An application of the nucleation theorem shows that the critical cluster consists of 22 water molecules and 5 methane molecules, for nucleation in pure methane. Growth rates of water droplets were measured in methane and in methane-carbon dioxide mixtures at 243 K and 11.5 bar. At equal temperature, pressure and water vapor fraction, the growth rate of the squared droplet radius is about 20% lower in the mixture with 25% carbon dioxide than in pure methane. The lower growth rate is caused by a smaller diffusion coefficient of water in the mixture with carbon dioxide; the difference of the diffusion coefficients is qualitatively reproduced by the empirical Fuller correlation combined with Blanc's law. PMID:20515097

  16. Source apportionment of PM10 mass and particulate carbon in the Kathmandu Valley, Nepal

    Science.gov (United States)

    Kim, Bong Mann; Park, Jin-Soo; Kim, Sang-Woo; Kim, Hyunjae; Jeon, Haeun; Cho, Chaeyoon; Kim, Ji-Hyoung; Hong, Seungkyu; Rupakheti, Maheswar; Panday, Arnico K.; Park, Rokjin J.; Hong, Jihyung; Yoon, Soon-Chang

    2015-12-01

    The Kathmandu Valley in Nepal is a bowl-shaped urban basin in the Himalayan foothills with a serious problem of fine particulate air pollution that impacts local health and impairs visibility. Particulate carbon concentrations have reached severe levels that threaten the health of 3.5 million local residents. Moreover, snow and ice on the Himalayan mountains are melting as a result of additional warming due to particulate carbon, especially high black carbon concentrations. To date, the sources of the Valley's particulate carbon and the impacts of different sources on particulate carbon concentrations are not well understood. Thus, before an effective control strategy can be developed, these particulate carbon sources must be identified and quantified. Our study has found that the four primary sources of particulate carbon in the Kathmandu Valley during winter are brick kilns, motor vehicles, fugitive soil dust, and biomass/garbage burning. Their source contributions are quantified using a recently developed new multivariate receptor model SMP. In contrast to other highly polluted areas such as China, secondary contribution is almost negligible in Kathmandu Valley. Brick kilns (40%), motor vehicles (37%) and biomass/garbage burning (22%) have been identified as the major sources of elemental carbon (black carbon) in the Kathmandu Valley during winter, while motor vehicles (47%), biomass/garbage burning (32%), and soil dust (13%) have been identified as the most important sources of organic carbon. Our research indicates that controlling emissions from motor vehicles, brick kilns, biomass/garbage burning, and soil dust is essential for the mitigation of the particulate carbon that threatens public health, impairs visibility, and influences climate warming within and downwind from the Kathmandu Valley. In addition, this paper suggests several useful particulate carbon mitigation methods that can be applied to Kathmandu Valley and other areas in South Asia with

  17. The stable carbon isotope composition of PM 2.5 and PM 10 in Mexico City Metropolitan Area air

    Science.gov (United States)

    López-Veneroni, D.

    The sources and distribution of carbon in ambient suspended particles (PM 2.5 and PM 10) of Mexico City Metropolitan Area (MCMA) air were traced using stable carbon isotopes ( 13C/ 12C). Tested potential sources included rural and agricultural soils, gasoline and diesel, liquefied-petroleum gas, volcanic ash, and street dust. The complete combustion of LP gas, diesel and gasoline yielded the lightest δ13C values (-27 to -29‰ vs. PDB), while street dust (PM 10) represented the isotopically heaviest endmember (-17‰). The δ13C values of rural soils from four geographically separated sites were similar (-20.7 ± 1.5‰). δ13C values of particles and soot from diesel and gasoline vehicle emissions and agricultural soils varied between -23 and -26‰. Ambient PM samples collected in November of 2000, and March and December of 2001 at three representative receptor sites of industrial, commercial and residential activities had a δ13C value centered around -25.1‰ in both fractions, resulting from common carbon sources. The predominant carbon sources to MCMA atmospheric particles were hydrocarbon combustion (diesel and/or gasoline) and particles of geological origin. The significantly depleted δ13C values from the industrial site reflect the input of diesel combustion by mobile and point source emissions. Based on stable carbon isotope mass balance, the carbon contribution of geological sources at the commercial and residential sites was approximately 73% for the PM 10 fraction and 54% for PM 2.5. Although not measured in this study, biomass-burning emissions from nearby forests are an important carbon source characterized by isotopically lighter values (-29‰), and can become a significant contributor (67%) of particulate carbon to MCMA air under the prevalence of southwesterly winds. Alternative sources of these 13C-depleted particles, such as cooking fires and municipal waste incineration, need to be assessed. Results show that stable carbon isotope

  18. Surface analysis and a novel application of carbon sheet pump in the GAMMA 10 tandem mirror

    International Nuclear Information System (INIS)

    Samples of carbon sheet pump (CSP) exposed to fast neutrals have been analyzed by using microscopic techniques in order to improve the performance of CSP and to examine the applicability of CSP to actual devices. It has been confirmed from the microscopic viewpoint for the first time that fast neutrals emitted from plasmas generated by the actual confinement device (GAMMA 10) are trapped by the C/C material. A numerical simulation is performed by means of the Monte Carlo simulation code TRIM (ver. TRVMC95) for the sake of the evaluation of the results obtained by elastic recoil detection technique. CSP has been newly applied to the shine-through beam dump of a neutral beam injector in order to test the pumping effect of CSP under the conditions of high heat and particle load (several MW/m2 and 2.5x1021 H/m2 s at the beam center, respectively). It also has been found from pressure-balance analysis that 80% of incident particles are trapped by CSP

  19. An evaluation of the neutron-induced reaction cross sections on carbon from 10 to 20 MeV

    International Nuclear Information System (INIS)

    Available data on the neutron-induced reactions on carbon are reviewed for the energy range from 10 to 20 MeV. Evaluated cross sections obtained at Bruyeres-le-Chatel are discussed. Comparisons with coupled-channel calculations are presented for the total, elastic and inelastic (to the 2+ level) cross sections of 12C

  20. Pore size effects on the sorption of supercritical carbon dioxide in mesoporous CPG-10 silica

    Energy Technology Data Exchange (ETDEWEB)

    Rother, Gernot [ORNL; Krukowski, Elizabeth G [ORNL; Wallacher, Dirk [Helmholtz-Zentrum Berlin; Grimm, Nico [Helmholtz-Zentrum Berlin; Bodnar, Robert J [ORNL; Cole, David [Ohio State University

    2012-01-01

    Excess sorption isotherms of supercritical carbon dioxide in mesoporous CPG-10 silica glasses with nominal pore sizes of 75 (7.5 nm) and 350 (35 nm) were measured gravimetrically at 35 C and 50 C and pressures of 0-200 bar. Formation of broad maxima in the excess sorption was observed at fluid densities below the bulk critical density. Positive values of excess sorption were measured at bulk densities below about 0.65-0.7 g/cm3, whereas zero and negative values were obtained at higher densities, indicating that the interfacial fluid becomes less dense than the corresponding bulk fluid at high fluid densities. A shift of the excess sorption peak position to higher fluid density is found with increasing pore width. The excess sorption of CO2 normalized to the specific surface area is higher for the 35 nm pore size material, suggesting pore confinement effects. Conversely, the pore volume normalized excess sorption is higher for the 7.5 nm pore size material. Assessment of mean pore density reveals regions of constant pore fluid density, located between the excess sorption peak and the adsorption/depletion transition. Both materials exhibit such regions of constant mean pore fluid density as a function of bulk CO2 density at the lower temperature of 35 C, but not at 50 C. The results of this study suggest that the CO2 storage capacity in quartz-rich reservoirs is higher for sites with low temperature and rock textures characterized by narrow pores with high surface to volume ratios.

  1. Improved routines to model the ocean carbonate system: mocsy 1.0

    Directory of Open Access Journals (Sweden)

    J. C. Orr

    2014-05-01

    Full Text Available Software used by modelers to compute ocean carbonate chemistry is often based on code from the Ocean Carbon Cycle Model Intercomparison Project (OCMIP, last revised in 2005. As an update, we offer here new publicly available Fortran 95 routines to model the ocean carbonate system (mocsy. Both codes take as input dissolved inorganic carbon CT and total alkalinity AT, the only two tracers of the ocean carbonate system that are unaffected by changes in temperature and salinity and conservative with respect to mixing, properties that make them ideally suited for ocean carbon models. With the same basic thermodynamic equilibria, both codes compute surface-ocean pCO2 in order to simulate air–sea CO2 fluxes. The mocsy package goes beyond the OCMIP code by computing all other carbonate system variables (e.g., pH, CO32−, and CaCO3 saturation states and by doing so throughout the water column. Moreover, it avoids three common model approximations: that density is constant, that modeled potential temperature is equivalent to in situ temperature, and that depth is equivalent to pressure. These approximations work well at the surface, but total errors in computed variables grow with depth, e.g., reaching −8 μatm in pCO2, +0.010 in pH, and +0.01 in ΩA at 5000 m. Besides the equilibrium constants recommended for best practices, mocsy also offers users three new options: (1 a recent formulation for total boron that increases its ocean content by 4%, (2 an older formulation for KF common to all other such software, and (3 recent formulations for K1 and K2 designed to also include low-salinity waters. More total boron increases borate alkalinity and reduces carbonate alkalinity, which is calculated as a difference from total alkalinity. As a result, the computed surface pCO2 increases by 4 to 6 μatm, while the computed aragonite saturation horizon (ASH shallows by 60 m in the North Atlantic and by up to 90 m in the Southern Ocean. Changes due to the new

  2. Exhaustive Analysis of a Genotype Space Comprising 10(15 Central Carbon Metabolisms Reveals an Organization Conducive to Metabolic Innovation.

    Directory of Open Access Journals (Sweden)

    Sayed-Rzgar Hosseini

    2015-08-01

    Full Text Available All biological evolution takes place in a space of possible genotypes and their phenotypes. The structure of this space defines the evolutionary potential and limitations of an evolving system. Metabolism is one of the most ancient and fundamental evolving systems, sustaining life by extracting energy from extracellular nutrients. Here we study metabolism's potential for innovation by analyzing an exhaustive genotype-phenotype map for a space of 10(15 metabolisms that encodes all possible subsets of 51 reactions in central carbon metabolism. Using flux balance analysis, we predict the viability of these metabolisms on 10 different carbon sources which give rise to 1024 potential metabolic phenotypes. Although viable metabolisms with any one phenotype comprise a tiny fraction of genotype space, their absolute numbers exceed 10(9 for some phenotypes. Metabolisms with any one phenotype typically form a single network of genotypes that extends far or all the way through metabolic genotype space, where any two genotypes can be reached from each other through a series of single reaction changes. The minimal distance of genotype networks associated with different phenotypes is small, such that one can reach metabolisms with novel phenotypes--viable on new carbon sources--through one or few genotypic changes. Exceptions to these principles exist for those metabolisms whose complexity (number of reactions is close to the minimum needed for viability. Increasing metabolic complexity enhances the potential for both evolutionary conservation and evolutionary innovation.

  3. CRADA Final Report for CRADA Number NFE-10-02991 "Development and Commercialization of Alternative Carbon Precursors and Conversion Technologies"

    Energy Technology Data Exchange (ETDEWEB)

    Norris, Rober [ORNL; Paulauskas, Felix [ORNL; Naskar, Amit [ORNL; Kaufman, Michael [ORNL; Yarborough, Ken [ORNL; Derstine, Chris [The Dow Chemical Company

    2013-10-01

    The overall objective of the collaborative research performed by the Oak Ridge National Laboratory (ORNL) and the Dow Chemical Company under this Cooperative Research And Development Agreement (CRADA NFE-10-02991) was to develop and establish pathways to commercialize new carbon fiber precursor and conversion technology. This technology is to produce alternative polymer fiber precursor formulations as well as scaled energy-efficient advanced conversion technology to enable continuous mode conversion to obtain carbonized fibers that are technically and economically viable in industrial markets such as transportation, wind energy, infrastructure and oil drilling applications. There have been efforts in the past to produce a low cost carbon fiber. These attempts have to be interpreted against the backdrop of the market needs at the time, which were strictly military aircraft and high-end aerospace components. In fact, manufacturing costs have been reduced from those days to current practice, where both process optimization and volume production have enabled carbon fiber to become available at prices below $20/lb. However, the requirements of the lucrative aerospace market limits further price reductions from current practice. This approach is different because specific industrial applications are targeted, most specifically wind turbine blade and light vehicle transportation, where aircraft grade carbon fiber is not required. As a result, researchers are free to adjust both manufacturing process and precursor chemistry to meet the relaxed physical specifications at a lower cost. This report documents the approach and findings of this cooperative research in alternative precursors and advanced conversion for production of cost-effective carbon fiber for energy missions. Due to export control, proprietary restrictions, and CRADA protected data considerations, specific design details and processing parameters are not included in this report.

  4. The present status of carbon 14 analysis and projects for beryllium 10 analysis at the Tandetron 1 accelerator, Nagoya University

    Energy Technology Data Exchange (ETDEWEB)

    Nakamura, Toshio; Oda, Hirotaka; Ikeda, Akiko; Niu, Etsuko [Nagoya Univ. (Japan)

    2001-02-01

    The operation experience in 1999 of the Tandetron accelerator age estimation system, Nagoya University, is reported, after the overview and the history of the accelerator is briefly described. Total number of carbon 14 environmental samples analyzed was 8567. The project of introducing new HVEE Tandetron for C-14 analysis, and modifying the present GIC Tandetron for Be-10 analysis is presented. Ion source shall be replaced, and the heavy ion detector shall be installed. Projected geological and archaeological studies using Be-10 are enumerated. (A. Yamamoto)

  5. Synthesis and biological evaluation of carbon-11 and fluorine-18 labeled tracers for in vivo visualization of PDE10A

    International Nuclear Information System (INIS)

    Introduction: In vivo visualization of PDE10A using PET provides a tool to evaluate the role of PDE10A in various neuropsychiatric diseases and can also be useful in the clinical evaluation of PDE10A inhibitor drug candidates. We evaluated several carbon-11 and fluorine-18 labeled PDE10A inhibitors as potential PDE10A PET radioligands. Materials and Methods: [11C]MP10, [11C]JNJ42071965 and four other tracers were developed. Their biodistribution was evaluated in rats. Rat plasma and brain radiometabolites were quantified. Baseline microPET imaging was performed in normal rats and PDE10A knockout (KO) and wild-type (WT) mice. Blocking and displacement studies were conducted. The selectivity of the tracer binding was further studied in an ex vivo autoradiography experiment in PDE10A KO and WT mice. Results: Biodistribution showed brain uptake for all tracers in the striatum and wash-out from the cerebellum. [11C]1 (11C-MP10) had the highest specific uptake index (striatum (S) vs. cerebellum (C) ratios (S/C)-1) at 60 min (7.4). [11C]5 ([11C]JNJ42071965) had a high index at the early time points (1.0 and 3.7 at 2 and 30 min p.i., respectively). The affinity of [11C]4, [18 F]3 and [18 F]6 was too low to visualize PDE10A using microPET. [11C] 2 showed a specific binding, while kinetics of [11C]1 were too slow. [11C]5 reached equilibrium after 10 min (uptake index = 1.2). Blocking and displacement experiments in rats and baseline imaging in PDE10A KO mice showed specific and reversible binding of [11C]5 to PDE10A. Conclusions: We successfully radiolabeled and evaluated six radiotracers for their potential to visualize PDE10A in vivo. While [11C]1 had the highest striatal specific uptake index, its slow kinetics likely compromise clinical use of this tracer. [11C]5 has a relatively high striatum-to-background ratio and fast kinetic profile, which makes it a valuable carbon-11 alternative

  6. Energy loss of 10 MeV/amu atomic helium in carbon

    Energy Technology Data Exchange (ETDEWEB)

    Ogawa, H.; Sakamoto, N. [Nara Women`s Univ. (Japan). Dept. of Physics; Katayama, I. [Institute for Nuclear Study, University of Tokyo, Tanashi, Tokyo 188 (Japan); Haruyama, Y.; Saito, M. [Laboratory of Applied Physics, Kyoto Prefectural University, Kyoto 606 (Japan); Yoshida, K. [Department of Nuclear Engineering, Kyoto University, Kyoto 606-01 (Japan); Tosaki, M. [Radio Isotope Research Center, Kyoto University, Kyoto 606 (Japan); Susuki, Y.; Kimura, K. [Department of Engineering Physics and Mechanics, Kyoto University, Kyoto 606-01 (Japan)

    1997-10-01

    Mean energy losses of 31.8 MeV neutral {sup 3}He atoms penetrating through thin carbon foils of 1.6-7.2 {mu}g/cm{sup 2} were measured using a high-resolution magnetic spectrograph. The measured particles are those entered into the carbon foil as {sup 3}He{sup 0} and emerged from it as {sup 3}He{sup 0}. From the attenuation measurement of {sup 3}He{sup 0} in the foils, we can regard the measured energy losses as those of {sup 3}He{sup 0} in a frozen charge state. The measured stopping power of carbon for 31.8 MeV {sup 3}He{sup 0} is 58.2 {+-} 4.9 eV/{mu}g/cm{sup 2}. Including our previous data for other partially clothed ions of the same velocity, the projectile atomic number dependence of the screening effect due to the bound electrons is roughly reproduced by the theoretical predictions based on the Born approximation. (orig.). 14 refs.

  7. Electroporative interleukin-10 gene transfer ameliorates carbon tetrachloride-induced murine liver fibrosis by MMP and TIMP modulation

    Institute of Scientific and Technical Information of China (English)

    Wen-ying CHOU; Cheng-nan LU; Tsung-hsing LEE; Chia-ling WU; Kung-sheng HUNG; Allan M CONCEJERO; Bruno JAWAN; Cheng-haung WANG

    2006-01-01

    Aim:Liver fibrosis represents a process of healing and scarring in response to chronic liver injury.Effective therapies for liver fibrosis are lacking.Interleukin-10 (IL-10) is a cytokine that downregulates pro-inflammatory responses and has a modulatory effect on hepatic fibrogenesis.The aim of this study was to investigate whether electroporative IL-10 gene therapy has an hepatic fibrolytic effect on mice.Methods:Hepatic fibrosis was induced by administering carbon tetrachloride (CCl4) for 10 weeks in mice.The human IL-10 expression plasmid was delivered via electroporation after hepatic fibrosis was established.Histopathology,reverse transcription polymerase chain reaction (RT-PCR) ,immunoblotting,and gelatin zymography were used to investigate the possible mechanisms of action of IL-10.Results:Human IL-10 gene therapy reversed CCl4-induced liver fibrosis in mice.RT-PCR revealed that IL-10 gene therapy attenuated liver TGF-β1,collagen αl,fibronectin,and cell adhesion molecule mRNA upregulation.Following gene transfer,both the activation of α-smooth muscle actin and cyclooxygenase-2 were significantly attenuated.Furthermore.IL-10 significantly inhibited matrix metalloproteinase-2 (MMP-2) and tissue inhibitors of matrix metalloproteinase (TIMP) activation after CCl4 intoxication.Conclusions:We demonstrated that IL-10 gene therapy attenuated CCl4-induced liver fibrosis in mice.IL-10 prevented upregulated fibrogenic and pro-inflammatory gene responses.Its collagenolytic effect may be attributed to MMP and TIMP modulation.IL-10 gene therapy may be an effective therapeutic modality against liver fibrosis with potential clinical use.

  8. Voltammetric Detection of Diquat at the Carbon Paste Electrode Containing a Ca10(PO46(OH2

    Directory of Open Access Journals (Sweden)

    Moulay Abderrahim EL MHAMMEDI

    2007-01-01

    Full Text Available We report a sensitive electrochemical voltammetric method for analyzing diquat (DQ ions using a carbon paste electrochemical (CPE modified by porous material, such as hydroxyapatite (HAP. Diquat strongly adsorbed on a HAP-CPE surface and provides facile electrochemical quantitative methods for electroactive DQ ions. Operational parameters have been optimized, and the stripping voltammetric performance has been studied using square wave voltammetry. The peaks current intensity are highly linear over the 7×10-7–3×10-4 mol L-1 diquat range examined (10-min accumulation time, with a good sensitivity. These findings can lead to a widespread use of electrochemical sensors to detect DQ contaminates.Scanning electron microscopy was used for morphology observation and in particular the X-ray diffraction analysis (XRD and Fourier transformed infrared spectroscopy (FTIR analysis for characterization of synthesis powder.

  9. An integrated Dissolved Organic Carbon Dynamics Model (DOCDM 1.0): model development and a case study in the Alaskan Yukon River Basin

    OpenAIRE

    Lu, X.; Zhuang, Q.

    2015-01-01

    Quantitative understanding of the variation in dissolved organic carbon (DOC) is important to studying the terrestrial ecosystem carbon cycle. This study presents a process-based, dissolved organic carbon dynamics model (DOCDM 1.0) that couples the soil heat conduction, water flow, DOC production, mineralization and transport in both surface and subsurface of soil profile to quantify DOC dynamics in boreal terrestrial ecosystems. The model...

  10. Improved recovery demonstration for Williston Basin carbonates. Annual report, June 10, 1995--June 9, 1996

    Energy Technology Data Exchange (ETDEWEB)

    Carrell, L.A.; Sippel, M.A.

    1996-09-01

    The purpose of this project is to demonstrate targeted infill and extension drilling opportunities, better determinations of oil-in-place, methods for improved completion efficiency and the suitability of waterflooding in Red River and Ratcliffe shallow-shelf carbonate reservoirs in the Williston Basin, Montana, North Dakota and South Dakota. Improved reservoir characterization utilizing three-dimensional and multi-component seismic are being investigated for identification of structural and stratigraphic reservoir compartments. These seismic characterization tools are integrated with geological and engineering studies. Improved completion efficiency is being tested with extended-reach jetting lance and other ultra-short-radius lateral technologies. Improved completion efficiency, additional wells at closer spacing and better estimates of oil in place will result in additional oil recovery by primary and enhanced recovery processes.

  11. The Bonding of NO2, NH3, and CH2NY to Models of a (10,0) Carbon Nanotube

    Science.gov (United States)

    Walch, Stephen P.

    2004-01-01

    We have studied the bonding of NO2, NH3, and CH2NH to a (10,O) carbon nanotube using the MP2 and ONIOM methods with extended basis sets. We find bond strengths of 3.5, 3.6. and 6.3 kcal/mol for NO2, NH3, and CH2NH, respectively, using the ONIOM method with the high accuracy part treated at the MP2/aug-CC-pVTZ level and the remainder of the CNT approximated at the UFF level and including an estimate of basis set superposition error using the counterpoise method.

  12. High-Temperature Interaction Between Molten AlSr10 Alloy and Glass-Like Carbon Substrate

    Science.gov (United States)

    Siewiorek, A.; Sobczak, N.; Sobczak, J.; Kudyba, A.; Kozera, R.; Boczkowska, A.

    2016-03-01

    Wettability of glass-like carbon substrate (Cglc) by molten Al-10 wt.% Sr alloy (AlSr10) has been examined by a sessile drop method at 700-800 °C for 120 min under vacuum. Non-contact heating to the test temperature combined with the removal of oxide film from the alloy drop was done using capillary purification procedure by squeezing the liquid alloy from a capillary. The influence of the type of capillary on wetting behavior of AlSr10/Cglc couples was noticed. Molten AlSr10 alloy does not wet Cglc at about 700 °C forming the contact angles of 111° with graphite capillary and 141° with alumina capillary. At 800 °C with alumina capillary, non-wetting-to-wetting transition takes place resulting in a final contact angle of 70°. After testing at 800 °C, the AlSr10/Cglc interface was revealed at the test temperature directly in the vacuum chamber by the drop suction procedure. Structural characterization of the interfaces by scanning and transmission electron microscopy combined with energy-dispersive x-ray spectroscopy and by scanning probe microscopy combined with Auger electron spectrometry did not show any new phases formed with Sr. It suggests that the dominant role in wettability improvement by alloying Al with 10 wt.% Sr was related with significant lowering of the surface tension of liquid metal and adsorption of Sr at the interface.

  13. Organic and elemental carbon associated to PM10 and PM 2.5 at urban sites of northern Greece.

    Science.gov (United States)

    Samara, Constantini; Voutsa, Dimitra; Kouras, Athanasios; Eleftheriadis, Kostas; Maggos, Thomas; Saraga, D; Petrakakis, M

    2014-02-01

    Organic carbon (OC) and elemental carbon (EC) concentrations, associated to PM10 and PM2.5 particle fractions, were concurrently determined during the warm and the cold months of the year (July-September 2011 and February-April 2012, respectively) at two urban sites in the city of Thessaloniki, northern Greece, an urban-traffic site (UT) and an urban-background site (UB). Concentrations at the UT site (11.3 ± 5.0 and 8.44 ± 4.08 14 μg m(-3) for OC10 and OC2.5 vs. 6.56 ± 2.14 and 5.29 ± 1.54 μg m(-3) for EC10 and EC2.5) were among the highest values reported for urban sites in European cities. Significantly lower concentrations were found at the UB site for both carbonaceous species, particularly for EC (6.62 ± 4.59 and 5.72 ± 4.36 μg m(-3) for OC10 and OC2.5 vs. 0.93 ± 0.61 and 0.69 ± 0.39 μg m(-3) for EC10 and EC2.5). Despite that, a negative UT-UB increment was frequently evidenced for OC2.5 and PM2.5 in the cold months possibly indicative of emissions from residential wood burning at the urban-background site. At both sites, cconcentrations of OC fractions were significantly higher in the cold months; on the contrary, EC fractions at the UT site were prominent in the warm season suggesting some influence from maritime emissions in the nearby harbor area. Secondary organic carbon, being estimated using the EC tracer method and seasonally minimum OC/EC ratios, was found to be an appreciable component of particle mass particularly in the cold season. The calculated secondary contributions to OC ranged between 35 and 59 % in the PM10 fraction, with relatively higher values in the PM2.5 fraction (39-61 %). The source origin of carbonaceous species was investigated by means of air parcel back trajectories, satellite fire maps, and concentration roses. A local origin was mainly concluded for OC and EC with limited possibility for long range transport of biomass (agricultural waste) burning aerosol. PMID:23979848

  14. 10 CFR 30.21 - Radioactive drug: Capsules containing carbon-14 urea for “in vivo” diagnostic use for humans.

    Science.gov (United States)

    2010-01-01

    ... 10 Energy 1 2010-01-01 2010-01-01 false Radioactive drug: Capsules containing carbon-14 urea for...: Capsules containing carbon-14 urea for “in vivo” diagnostic use for humans. (a) Except as provided in...-14 urea (allowing for nominal variation that may occur during the manufacturing process) each,...

  15. Carbon concentrations of components of trees in 10-year-old Populus davidiana stands within the Desertification Combating Program of Northern China

    Science.gov (United States)

    Shen, Huitao; Zhang, Wanjun; Cao, Jiansheng; Zhang, Xiang; Xu, Quanhong; Yang, Xue; Xiao, Dengpan; Zhao, Yanxia

    2016-03-01

    Most studies do not consider the potential variation in carbon concentration among the different tree components of the same species in regional scale. This study examined the carbon concentrations of the components (i.e., foliage, branch, stem, and root) in a 10-year-old poplar species (Populus davidiana Dode) from the Desertification Combating Program of Northern China. The highest and lowest carbon concentrations were found in the stem and foliage, respectively. There was a significant difference in carbon concentrations among the different tree components. All of the observed carbon concentrations of tree components were lower than those predicted using the conversion factor of 0.5 applied to component biomass. Stem carbon made up 59.7% of the total tree biomass carbon. The power equation estimating proportion of tree biomass carbon against the independent variable of diameter at breast height explained more than 90% of the variability in allocation of carbon among tree components. Tree height, as a second independent variable is also discussed. Our results suggest that the difference in organic carbon concentration among tree components should be incorporated into accurately develop forest carbon budget. Moreover, further investigations on how the diameter at breast height equation developed in the present study performs across broader scales are required.

  16. Increased strength characteristics of low carbon micro-alloyed steel grade 10g2fb

    OpenAIRE

    Nosenko, O. P.

    2016-01-01

    Aim. The purpose of research is the search of new technological methods of increasing mechanical and performance properties of the steel grade 10G2FB for metal structures of responsible appointment. Methods. The structure of the steel samples wasstudied by qualitative and quantitative light microscopy at microscopes "Epikvant", "Neofot-2". Testing mechanical properties of tensile was carried out according to DSTU EN 10002 1:. 2006, toughness was determined on a U- and V-notch samples for Stat...

  17. Elemental and organic carbon in PM10: a one year measurement campaign within the European Monitoring and Evaluation Programme EMEP

    Directory of Open Access Journals (Sweden)

    W. Maenhaut

    2007-03-01

    Full Text Available In the present study, ambient aerosol (PM10 concentrations of elemental carbon (EC, organic carbon (OC, and total carbon (TC are reported for 12 European rural background sites and two urban background sites following a one-year (1 July 2002–1 July 2003 sampling campaign within the European Monitoring and Evaluation Programme, EMEP (http://www.emep.int/. The purpose of the campaign was to assess the feasibility of performing EC and OC monitoring on a regular basis and to obtain an overview of the spatial and seasonal variability on a regional scale in Europe. Analyses were performed using the thermal-optical transmission (TOT instrument from Sunset Lab Inc., operating according to a NIOSH derived temperature program. The annual mean mass concentration of EC ranged from 0.17±0.19 μg m−3 (mean ± SD at Birkenes (Norway to 1.83±1.32 μg m−3 at Ispra (Italy. The corresponding range for OC was 1.20±1.29 μg m−3 at Mace Head (Ireland to 7.79±6.80 μg m−3 at Ispra. On average, annual concentrations of EC, OC, and TC were three times higher for rural background sites in Central, Eastern and Southern Europe compared to those situated in the Northern and Western parts of Europe. Wintertime concentrations of EC and OC were higher than those recorded during summer for the majority of the sites. Moderate to high Pearson correlation coefficients (rp (0.50–0.94 were observed for EC versus OC for the sites investigated. The lowest correlation coefficients were noted for the three Scandinavian sites: Aspvreten (SE, Birkenes (NO, and Virolahti (FI, and the Slovakian site Stara Lesna, and are suggested to reflect biogenic sources, wild and prescribed fires. This suggestion is supported by the fact that higher concentrations of OC are observed for summer compared to winter for these sites. For the rural background sites, total carbonaceous material accounted for 30±9% of PM10, of which 27±9% could be attributed to organic matter (OM and 3.4±1.0

  18. Elemental and organic carbon in PM10: a one year measurement campaign within the European Monitoring and Evaluation Programme EMEP

    Directory of Open Access Journals (Sweden)

    W. Maenhaut

    2007-11-01

    Full Text Available In the present study, ambient aerosol (PM10 concentrations of elemental carbon (EC, organic carbon (OC, and total carbon (TC are reported for 12 European rural background sites and two urban background sites following a one-year (1 July 2002–1 July 2003 sampling campaign within the European Monitoring and Evaluation Programme, EMEP http://www.emep.int/. The purpose of the campaign was to assess the feasibility of performing EC and OC monitoring on a regular basis and to obtain an overview of the spatial and seasonal variability on a regional scale in Europe. Analyses were performed using the thermal-optical transmission (TOT instrument from Sunset Lab Inc., operating according to a NIOSH derived temperature program. The annual mean mass concentration of EC ranged from 0.17±0.19 μg m−3 (mean ± SD at Birkenes (Norway to 1.83±1.32 μg m−3 at Ispra (Italy. The corresponding range for OC was 1.20±1.29 μg m−3 at Mace Head (Ireland to 7.79±6.80 μg m−3 at Ispra. On average, annual concentrations of EC, OC, and TC were three times higher for rural background sites in Central, Eastern and Southern Europe compared to those situated in the Northern and Western parts of Europe. Wintertime concentrations of EC and OC were higher than those recorded during summer for the majority of the sites. Moderate to high Pearson correlation coefficients (rp (0.50–0.94 were observed for EC versus OC for the sites investigated. The lowest correlation coefficients were noted for the three Scandinavian sites: Aspvreten (SE, Birkenes (NO, and Virolahti (FI, and the Slovakian site Stara Lesna, and are suggested to reflect biogenic sources, wild and prescribed fires. This suggestion is supported by the fact that higher concentrations of OC are observed for summer compared to winter for these sites. For the rural background sites, total carbonaceous material accounted for 30±9% of PM10, of which 27±9% could be attributed to organic matter (OM and 3.4±1.0

  19. Investigations of adsorption states of protium and deuterium in redeposited carbon flakes formed in tokamak T-10

    International Nuclear Information System (INIS)

    This work reports thermal desorption spectroscopy (TDS), Fourier-transform infrared (FT-IR) spectroscopy and X-ray diffraction (XRD) analyses on free standing redeposited hydrocarbon films (flakes) with a high deuterium to hydrogen isotopic ratio, produced in the T-10 tokamak in the Kurchatov Institute. XRD pattern showed that the carbon flakes differ substantially from graphite and are non-crystalline. The TDS D2(H2) curves consist of two groups of peaks (450-800 K and 900-1000 K), and appeared to be rather similar to those obtained for a mechanically milled nanostructured graphite. As a result, two main adsorption states with activation energies of about 0.65 and 1.25 eV/H were found, implying a hopping diffusion and a resonance mechanism, respectively. The IR spectral differences between reddish-gold and dark-brown flakes showed a less degree of C-H hybridization for dark films and a disordered carbon network, to which the CD2,3 end-groups are connected

  20. Study the structure of neutron deficient carbon isotopes: 10C and 11C. Elastic and inelastic scattering on proton target

    International Nuclear Information System (INIS)

    This work is devoted to the study of the structure of neutron-deficient carbon isotopes: 10C and 11C. A theoretical model predicts a special behaviour for these nuclei: different deformations for neutron and proton densities. To test these predictions and to obtain information on the structure of these nuclei, we measured angular distribution for elastic and inelastic scattering on proton target with inverse kinematics at 40 MeV per nucleon. The angular distribution is deduced from the proton energy and angle scattering, measured by the MUST detector. Experimental set-up is completed with plastic detectors for scattered nucleus identification and with two CATS detectors for measurement of position and angle for each beam particle on the target. Angular distributions are calculated with an analytic method. This method is tested with a simulation and with 12C + p scattering analysis. Angular distributions are analysed in terms of a complex microscopic potential JLM with different microscopic matter densities. Elastic scattering gives an information on 10C and 11C matter root mean square radii. Both radii are larger than the one for the stable 12C isotope. Inelastic scattering is treated in DWBA approximation with microscopic transition densities. 10C inelastic scattering gives an information on neutron contribution of nucleus excitation. With 11C inelastic scattering, we could constrain transition densities and we could extract an information on the type of the transition. However, it is very difficult to confirm or to annul predictions of different deformations for proton and neutrons densities. (author)

  1. Experimental water content measurements of carbon dioxide in equilibrium with hydrates at (223.15 to 263.15) K and (1.0 to 10.0) MPa

    International Nuclear Information System (INIS)

    Highlights: • Experimental water content data for carbon dioxide in equilibrium with hydrates. • Data required for setting drying requirements in carbon dioxide streams. • Comparison of experimental data with model predictions and available literature data. -- Abstract: The environmental impact of carbon dioxide has led to the need for capture and storage processes. Whenever water is present, at conditions inside the carbon dioxide hydrate stability zone, there is the possibility of hydrate formation which can cause problems such as pipeline restriction and blockage. To avoid such problems it is essential to know how dry the carbon dioxide needs to be. The measurement of the water content of carbon dioxide in equilibrium with hydrates at different temperature and pressure conditions gives a value below which hydrates will not form. There is a scarcity of relevant experimental data especially at low temperatures (<263.15 K). This is in part due to the challenging nature of making accurate equilibrium water content measurements at these conditions. The experimental data can be used to compare with predictions made using different thermodynamic models. This paper presents experimental equipment, methods and results for the water content of carbon dioxide in equilibrium with hydrates at temperatures between (223.15 and 263.15) K and pressures between (1.0 and 10.0) MPa, hence in both vapour and liquid phases. The experimental data are compared with predictions from an in-house (previously developed) thermodynamic model

  2. CV-Dust: Atmospheric aerosol in the Cape Verde region: carbon and soluble fractions of PM10

    Science.gov (United States)

    Pio, C.; Nunes, T.; Cardoso, J.; Caseiro, A.; Custódio, D.; Cerqueira, M.; Patoilo, D.; Almeida, S. M.; Freitas, M. C.

    2012-04-01

    than 100 PM10 samples, addressing mainly their mass concentrations and the chemical composition of water soluble ions and carbon species (carbonates and organic and elemental carbon). Different PM10 samplers worked simultaneously in order to collect enough mass to make the aerosol characterization through the different methodologies and to collect aerosols in different filter matrixes, which have to be appropriated to the chemical and mineralogical analysis. The sampling site was located at Santiago Island, in the surroundings of Praia City (14° 55' N e 23° 29' W, 98 m at sea level). High concentrations, up to more than 400 μg m-3, are connected to north-east and north-northeast winds, and it was identified several dust events characteristic of "bruma seca", whose duration is on average of two to four days. Backward trajectories analysis confirms that the high concentrations in Cape Verde are associated with air masses passing over the Sahara. During dust events the percentage of inorganic water soluble ions for the total PM10 mass concentration decreased significantly to values lower than 10% in comparison with remainder data that range around 45±10%. Acknowledgement: This work was funded by the Portuguese Science Foundation (FCT) through the project PTDD/AAC-CLI/100331/2008 and FCOMP-01-0124-FEDER-008646 (CV-Dust). J. Cardoso acknowledges the PhD grant SFRH-BD-6105-2009 from FCT.

  3. Including a full carbon cycle into the iLOVECLIM model (v1.0)

    OpenAIRE

    N. Bouttes; Roche, D. M.; V. Mariotti-Epelbaum; L. Bopp

    2014-01-01

    The atmospheric carbon dioxide concentration plays a crucial role in the radiative balance and as such has a strong influence on the evolution of climate. Because of the numerous interactions between climate and the carbon cycle, it is necessary to include a model of the carbon cycle within a climate model to understand and simulate past and future changes of the carbon cycle. In particular, natural variations of atmospheric CO2 have happened in the past, wh...

  4. Thermometry using 1/8 W carbon resistors in a temperature region around 10 mK

    International Nuclear Information System (INIS)

    The resistance-temperature characteristics of 1/8 W carbon resistors of grade ERC-18SG, manufactured by Matsushita, with the nominal values of 48, 82, 100, 220 and 330 Ω have been measured in the region 4.2 K to 25 mK and their application as thermometers in this region is confirmed. For the 82 Ω resistor, measurements were taken at temperatures below 10mK. The temperature dependence of the resistance was found to be linear on the log-log plot over a wide range below 50 mK. The sensitivity remains finite even at 6 mK, but below 10 mK rapid measurements were prevented by a considerable increase in the thermal relaxation time. Measurement of the characteristics of several 100 Ω resistors from two different sets showed that resistors from the same set separate into two groups with different characteristics. This become appreciable at temperatures below 4.2 K, so it is difficult to predict the behaviour of Matsushite resistors below 4.2 K from the characteristics at higher temperatures. (author)

  5. Formulation of an organic carbon trajectory over a 10-year period on a restored spoil island in south-central Florida

    Science.gov (United States)

    Schafer, T.; Ellis, R.; Osborne, T.; Hicks Pries, C.

    2015-12-01

    Long-term monitoring of restoration projects aims to determine long-term sustainability and stability of restored systems. In coastal wetlands, one indicator of restoration of ecosystem function can be seen with organic matter (specifically carbon) accretion. SL-15, a spoil island in Fort Pierce, Fl was restored in 2005, and has been monitored for return to natural condition over the last 10 years.. To assess sediment carbon accretion, sediment cores were collected in a set of eight plots, located on the SL-15 mangrove island and the surrounding seagrass recruitment area. These were analyzed for organic carbon, microbial biomass carbon, extractable carbon, and total nitrogen. The biogeochemical data collected in the previous year was compared to data collected in 2005-2007. Vegetation surveys were also completed to show the build-up of organic material in accordance with vegetation shift over the 9-year period. From this information, a trajectory has been formulated on organic carbon accretion and vegetation shift from the time of orginal restoration activities. By comparison to control sites nearby, realistic estimates of time required to reach natural levels of carbon and vegetation community structure can be calculated..

  6. Highly selective electrodeposition of sub-10 nm crystalline noble metallic nanorods inside vertically aligned multiwall carbon nanotubes.

    Science.gov (United States)

    Wang, Xuyang; Wang, Ranran; Wu, Qiang; Zhang, Xiaohua; Yang, Zhaohui; Guo, Jun; Chen, Muzi; Tang, Minghua; Cheng, Yajun; Chu, Haibin

    2016-07-01

    In this paper crystalline noble metallic nanorods including Au and Ag with sub-10 nm diameter, are encapsulated within prealigned and open-ended multiwall carbon nanotubes (MWCNTs) through an electrodeposition method. As the external surface of CNTs has been insulated by the epoxy the CNT channel becomes the only path for the mass transport as well as the nanoreactor for the metal deposition. Highly crystallized Au and Ag2O nanorods parallel to the radial direction of CNTs are confirmed by high-resolution transmission electron microscopy, energy dispersive x-ray spectroscopy and x-ray powder diffraction spectroscopy. The Ag2O nanorods are formed by air oxidation on the Ag metals and show a single crystalline structure with (111) planes. The Au nanorods exhibit a complex crystalline structure including twin-crystal and lattice dislocation with (111) and (200) planes. These crystalline noble metallic nanostructures may have important applications for nanocatalysts for fuel cells as well as nanoelectronic and nanophotonic devices. This method is deemed to benefit the precise deposition of other crystalline nanostructures inside CNTs with a small diameter. PMID:27240546

  7. Isothermal Reduction of Oxide Scale on Hot-Rolled, Low-Carbon Steel in 10 pct H2-Ar

    Science.gov (United States)

    He, Yongquan; Jia, Tao; Li, Zhifeng; Cao, Guangming; Liu, Zhenyu; Li, Jun

    2016-08-01

    The isothermal reduction of oxide scale on hot-rolled, low-carbon steel strip in 10 pct H2-Ar mixtures in the temperature range of 673 K to 1073 K (400 °C to 800 °C) was investigated by using a thermo-gravimetric analyzer (TGA). During heating under an argon atmosphere, magnetite/iron eutectoid and proeutectoid magnetite in the oxide scale successively transformed into wüstite at a temperature above 843 K (570 °C). The kinetic plot of the isothermal reduction assumes a sigmoid shape, including induction, acceleration, and finally the decaying stage. Fitting the kinetic curve to mathematical models, the reaction at 1073 K (800 °C) and 773 K (500 °C) were determined to be controlled by phase-boundary-controlled reaction and three-dimensional growth of nuclei, respectively. The reduction product varies with temperature and itself affects the kinetics. Porous and dense iron were, respectively, obtained below and above 873 K (600 °C). A "rate-minimum" was observed at 973 K (700 °C) due to the formation of dense iron that blocks the gas diffusion. Due to the structural transformation of oxide scale during heating, the reactant depends on the heating process. However, compared with the oxide scale structure, the temperature is more important in determining the reduction kinetics at temperatures above 973 K (700 °C).

  8. Effects of changes in residential end-uses and behavior on aggregate carbon intensity. Comparison of 10 OECD countries for the period 1970 through 1993

    Energy Technology Data Exchange (ETDEWEB)

    Greening, L.A. [Consultant, 7780 Heights Court, Falls Church, VA 22043 Marshall (United States); Ting, M.; Krackler, T.J. [Energy and Environmental Division, Lawrence Berkeley National Laboratory, Berkeley, CA (United States)

    2001-03-01

    Patterns of the evolution of aggregate carbon intensity from residential end uses show greater variability than other sectors. For some countries in this analysis, this measure exhibits significant decreases, while for other countries this measure exhibits significant increases over the period of analysis. The Adaptive Weighted Divisia rolling base year index specification is applied to carbon emissions from the residential sector for 10 OECD countries for the period 1970-1993. Decreases in aggregate carbon intensity for six of the countries range less than 8% to almost 72%, and may be attributed to changes in three different factors. However, for all of the countries, decreases are offset by shifts in end-use structure toward more carbon-intensive activities. These shifts are driven by an increase in the number of households with a corresponding increase in floor space, acquisition of greater numbers of major appliances and by an increase in the 'other' energy consumption category.

  9. Measurements of hydrogen, oxygen and carbon isotope ratios by SIRA 10 mass spectrometer and some problems of their quality assurance

    International Nuclear Information System (INIS)

    Full text: Hydrogen and oxygen are two chemical elements that combined between them forms the water molecules. Hydrogen has two stable isotopes 1H and 2H, with abundance, respectively, 99.985 % and 0.015 %, while the oxygen has three stable isotopes 16O, 17O, 18O with the abundance, respectively, 99.756 %, 0.039 %, 0.205 %. Hydrogen and oxygen stable isotopes, in our laboratory, are used in the hydrology and hydrogeology studies. The 'δ' values of hydrogen and oxygen of water samples are expressed in per mille with respect to SMOW, while, for carbon is expressed in per mille with respect to PDB. The isotopic compositions of these elements are measured using the SIRA 10 mass spectrometer, which is similar with the Nier mass spectrometer. SIRA 10 mass spectrometer, destined for the measurements of the isotopic ratios of the light elements, is equipped with double inlet system and with three collectors system (for the oxygen, carbon, nitrogen etc. isotopes) and double collector system for the hydrogen isotopes. The vacuum 10-9 torr is realized by the two oil diffusion pumps. The gas samples (H2, CO2, etc.) are admitted to the ion source of the mass spectrometer, where are transformed into positive ions by the electron impact. The magnetic field is normal to the path of the ions and is realized by a permanent magnet. The quality assurance of the 'δ' determination dependent from the preparation of the gas samples and from the measurements of the isotopic ratios. Stable isotopes hydrogen of the water samples are measured through the hydrogen gas which is gained from the water by the reduction reaction with metallic Zinc in a separate line, in vacuum conditions and high temperature. The reduction process of the water was occurred not normally because in the inside of the glass balloons seems water droplets. The different experiments of the changes the water quantity, Zinc quantity, dimensions of the metallic Zinc and the temperature of the reduction reaction didn

  10. 77 FR 31351 - Adequacy Determination for Aspen PM10 and Fort Collins Carbon Monoxide Maintenance Plans' Motor...

    Science.gov (United States)

    2012-05-25

    ... (69 FR 40004). In addition, in certain areas with monitored ambient carbon monoxide (CO) values... the National Ambient Air Quality Standard (NAAQS). The criteria by which we determine whether a SIP... AGENCY Adequacy Determination for Aspen PM and Fort Collins Carbon Monoxide Maintenance Plans'...

  11. Carbonate measurements in PM10 near the marble quarries of Carrara (Italy) by infrared spectroscopy (FT-IR) and source apportionment by positive matrix factorization (PMF)

    Science.gov (United States)

    Cuccia, E.; Piazzalunga, A.; Bernardoni, V.; Brambilla, L.; Fermo, P.; Massabò, D.; Molteni, U.; Prati, P.; Valli, G.; Vecchi, R.

    2011-11-01

    The concentration of carbonates in atmospheric Particulate Matter (PM) is usually quite low. The surroundings of marble quarries are peculiar sites where the impact of carbonates in PM levels can be significant. We present here the results of a PM10 sampling campaign performed in Carrara (Italy). The town lies between the famous marble quarries and the harbour: about 1000 trucks per day transport marble blocks and debris from the quarries to the harbour passing through the town centre. PM10 was collected on daily basis on PTFE filters analyzed by Energy-Dispersive X-Ray Fluorescence (ED-XRF) and Ion-Chromatography (IC). Carbonate concentration was measured by a non-destructive Infrared Spectroscopy analysis (FT-IR). Time series of elemental (Na-Pb by ED-XRF), ionic (SO 42-, NH 4+ by ion-chromatography) and carbonate (by FT-IR) concentration values were merged in a unique data set and a PMF analysis singled out the major PM10 sources in the area. Marble transportation turned out to be the major pollution source in the town accounting to PM10 for about 36%; this corresponded to a CaCO 3 average level of about 8 μg m -3 during working days. The FT-IR analysis was a crucial part of the work and an ad-hoc analytical procedure was specifically set up, calibrated, and tested as described in the text.

  12. Traffic emissions of elemental carbon (EC) and organic carbon (OC) and their contribution to PM2.5 and PM10 urban background concentrations

    Energy Technology Data Exchange (ETDEWEB)

    Keuken, M.P. [Netherlands Organization for Applied Scientific Research TNO, Delft (Netherlands); Ten Brink, H.M. [ECN Biomass, Coal and Environmental Research, Petten (Netherlands)

    2009-09-15

    The contribution of carbon to particulate matter is larger in urban areas than outside those areas. The increment in urban EC and OC concentrations was found mainly to be caused by traffic emissions. The average annual increment was about 0.5 {mu}g/m{sup 3}. As a consequence, the potential to reduce urban background concentrations by abatement of traffic exhaust emissions, is small. However, from a health point of view, a reduction of carbon in PM is believed to be important.

  13. Efficacy and safety of 10,600-nm carbon dioxide fractional laser on facial skin with previous volume injections

    Directory of Open Access Journals (Sweden)

    Josiane Hélou

    2013-01-01

    Full Text Available Background: Fractionated carbon dioxide (CO 2 lasers are a new treatment modality for skin resurfacing. The cosmetic rejuvenation market abounds with various injectable devices (poly-L-lactic acid, polymethyl-methacrylate, collagens, hyaluronic acids, silicone. The objective of this study is to examine the efficacy and safety of 10,600-nm CO 2 fractional laser on facial skin with previous volume injections. Materials and Methods: This is a retrospective study including 14 patients treated with fractional CO 2 laser and who have had previous facial volume restoration. The indication for the laser therapy, the age of the patients, previous facial volume restoration, and side effects were all recorded from their medical files. Objective assessments were made through clinical physician global assessment records and improvement scores records. Patients′ satisfaction rates were also recorded. Results: Review of medical records of the 14 patients show that five patients had polylactic acid injection prior to the laser session. Eight patients had hyaluronic acid injection prior to the laser session. Two patients had fat injection, two had silicone injection and one patient had facial thread lift. Side effects included pain during the laser treatment, post-treatment scaling, post-treatment erythema, hyperpigmentation which spontaneously resolved within a month. Concerning the previous facial volume restoration, no granulomatous reactions were noted, no facial shape deformation and no asymmetry were encountered whatever the facial volume product was. Conclusion: CO 2 fractional laser treatments do not seem to affect facial skin which had previous facial volume restoration with polylactic acid for more than 6 years, hyaluronic acid for more than 0.5 year, silicone for more than 6 years, or fat for more than 1.4 year. Prospective larger studies focusing on many other variables (skin phototype, injected device type are required to achieve better

  14. ULTRA LOW POWER SINGLE EDGE TRIGGERED DELAY FLIP FLOP BASED SHIFT REGISTERS USING 10-NANOMETER CARBON NANO TUBE FIELD EFFECT TRANSISTOR

    Directory of Open Access Journals (Sweden)

    Ravi Thiyagarajan

    2013-01-01

    Full Text Available Carbon Nano Tube Field Effect Transistor is currently considered as promising successor of Metal Oxide Semiconductor Field Effect Transistor. The scaling down of the Metal Oxide Semiconductor device faced serious limits like short channel effect, tunnelling through gate oxide layer, associated leakage currents and power dissipation when its dimension shrink down to 22 nanometer range. Further scaling of Metal Oxide Semiconductor Field Effect Transistor will result in performance degradation. In this study, an ultra low power Single Edge Triggered Delay Flip Flop and shift registers are designed using 10 nanometre Carbon Nano Tube Field Effect Transistor. The Carbon Nano Tube Field Effect Transistor is an efficient device to supplant the current Complementary Metal Oxide Semiconductor technology for its excellent electrical properties. The high electron and hole mobility of semiconductor nano tubes, their compatibility with high k gate dielectrics, enhanced electrostatics, reduced short channel effects and ability to readily form metal ohmic contacts make these miniaturized structures an ideal material for high performance, nanoscale transistors. To evaluate the performance of Ultra low power Single Edge Triggered Delay Flip Flop and shift registers using 10 nanometer Carbon Nano Tube Field Effect Transistor technology, the results are depicted by analyzing average power, delay, power delay product, rise time and fall time using HSPICE at 1GHz operating frequency.

  15. Hydrogen Storage in Pristine and d10-Block Metal-Anchored Activated Carbon Made from Local Wastes

    OpenAIRE

    Mohamed F. Aly Aboud; Zeid A. ALOthman; Mohamed A. Habila; Claudia Zlotea; Michel Latroche; Fermin Cuevas

    2015-01-01

    Activated carbon has been synthesized from local palm shell, cardboard and plastics municipal waste in the Kingdom of Saudi Arabia. It exhibits a surface area of 930 m2/g and total pore volume of 0.42 cm3/g. This pristine activated carbon has been further anchored with nickel, palladium and platinum metal particles by ultrasound-assisted impregnation. Deposition of nanosized Pt particles as small as 3 nm has been achieved, while for Ni and Pd their size reaches 100 nm. The solid-gas hydrogena...

  16. Hydrogen Storage in Pristine and d10-Block Metal-Anchored Activated Carbon Made from Local Wastes

    Directory of Open Access Journals (Sweden)

    Mohamed F. Aly Aboud

    2015-04-01

    Full Text Available Activated carbon has been synthesized from local palm shell, cardboard and plastics municipal waste in the Kingdom of Saudi Arabia. It exhibits a surface area of 930 m2/g and total pore volume of 0.42 cm3/g. This pristine activated carbon has been further anchored with nickel, palladium and platinum metal particles by ultrasound-assisted impregnation. Deposition of nanosized Pt particles as small as 3 nm has been achieved, while for Ni and Pd their size reaches 100 nm. The solid-gas hydrogenation properties of the pristine and metal-anchored activated carbon have been determined. The pristine material exhibits a reversible hydrogen storage capacity of 2.3 wt% at 77 K and 3 MPa which is higher than for the doped ones. In these materials, the spillover effect due to metal doping is of minor importance in enhancing the hydrogen uptake compared with the counter-effect of the additional mass of the metal particles and pore blocking on the carbon surface.

  17. A glassy carbon electrode modified with the nickel(II)-bis(1,10-phenanthroline) complex and multi-walled carbon nanotubes, and its use as a sensor for ascorbic acid

    International Nuclear Information System (INIS)

    A glassy carbon electrode (GCE) was modified with the nickel(II)-bis(1,10-phenanthroline) complex and with multi-walled carbon nanotubes (MWCNTs). The nickel complex was electrodeposited on the MWCNTs by cyclic voltammetry. The modified GCE displays excellent electrocatalytic activity to the oxidation of ascorbic acid (AA). The effects of fraction of MWCNTs, film thickness and pH values were optimized. Response to AA is linear in the 10 to 630 μM concentration range, and the detection limit is 4 μM (at a signal-to-noise ratio of 3:1). The modified electrode was applied to determine AA in vitamin C tablets and in spiked fruit juice. (author)

  18. Carbon Monoxide Inhibits Tenascin-C Mediated Inflammation via IL-10 Expression in a Septic Mouse Model

    OpenAIRE

    Md. Jamal Uddin; Chun-shi Li; Yeonsoo Joe; Yingqing Chen; Qinggao Zhang; Ryter, Stefan W.; Hun Taeg Chung

    2015-01-01

    Tenascin-C (TN-C), an extracellular matrix (ECM) glycoprotein, is specifically induced upon tissue injury and infection and during septic conditions. Carbon monoxide (CO) gas is known to exert various anti-inflammatory effects in various inflammatory diseases. However, the mechanisms underlying the effect of CO on TN-C-mediated inflammation are unknown. In the present study, we found that treatment with LPS significantly enhanced TN-C expression in macrophages. CO gas, or treatment with the C...

  19. Modeling soil organic carbon stock after 10 years of cover crops in Mediterranean vineyards: improving ANN prediction by digital terrain analysis.

    Science.gov (United States)

    Lo Papa, Giuseppe; Novara, Agata; Santoro, Antonino; Gristina, Luciano

    2014-05-01

    Estimate changes in soil organic carbon (SOC) stock after Agro Environment Measures adoption are strategically for national and regional scale. Uncertainty in estimates also represents a very important parameter in terms of evaluation of the exact costs and agro environment payments to farmers. In this study we modeled the variation of SOC stock after 10-year cover crop adoption in a vine growing area of South-Eastern Sicily. A paired-site approach was chosen to study the difference in SOC stocks. A total 100 paired sites (i.e. two adjacent plots) were chosen and three soil samples (Ap soil horizons, circa 0-30 cm depth) were collected in each plot to obtain a mean value of organic carbon concentration for each plot. The variation of soil organic carbon (SOCv) for each plot was calculated by differences between concentrations of the plot subjected to cover crops (SOC10) and the relative plot subjected to traditional agronomic practices (SOC0). The feasibility of using artificial neural networks as a method to predict soil organic carbon stock variation and the contribution of digital terrain analysis to improve the prediction were tested. We randomly subdivided the experimental values of SOC-stock difference in 80 learning samples and 20 test samples for model validation. SOCv was strongly correlated to the SOC0 concentration. Model validation using only SOCv as unique covariate showed a training and test perfection of 0.724 and 0.871 respectively. We hypothesized that terrain-driven hydrological flow patterns, mass-movement and local micro-climatic factors could be responsible processes contributing for SOC redistributions, thus affecting soil carbon stock in time. Terrain attributes were derived by digital terrain analysis from the 10 m DEM of the study area. A total of 37 terrain attributes were calculated and submitted to statistical feature selection. The Chi-square ranking indicated only 4 significant covariates among the terrain attributes (slope height

  20. Experimental study on corrosion behavior of carbon steel in buffer material-I. Behavior of corrosion propagation based on the results of immersion tests for 10 years

    International Nuclear Information System (INIS)

    The deep underground environment where overpacks will be emplaced is expected to be anaerobic environment. It is necessary to understand the corrosion behavior of carbon steel in such environment for the assessment of corrosion lifetime of carbon steel overpacks. In this study, immersion tests of carbon steel were carried out in buffer material for 10 years duration in nitrogen atmosphere in which oxygen gas concentration was controlled to less than 1 ppm. Synthetic sea water and aqueous solution containing bicarbonate ion and chloride ion were selected as the test solution. The effects of temperature, bentonite purity and atmosphere on the corrosion behavior were investigated. The amount of corrosion of carbon steel was estimated from the weight loss of the test coupon, and its change with time was investigated. The experimental results were summarised as follows; The corrosion rates were decreased with time in every test case, and as the corrosion rate at early stage of immersion was larger, the corrosion propagation was more suppressed after a long term. The influence of purity of bentonite and the atmosphere of gas phase on the behavior of corrosion propagation was small. The amount of corrosion in high carbonate concentration was smaller than those of other test conditions throughout the test periods. The change of corrosion depth, Y with time, X was approximated by power law equation, Y=AXB. The parameter A and B in synthetic sea water system was expressed as a function of dry density of buffer material, ρ(g/cm3), sand mixing ratio, r(0 ≤ r ≤ 1) and temperature, T(K). The corrosion rates calculated from the gradient of the change of the average corrosion depth between 1 to 10 years were in the range of 0.055 - 1.4 μm/y. It was confirmed that the corrosion rate of 10 μm/y used in the past lifetime assessment of overpack was sufficiently conservative in comparison with laboratory test data for 10 years and natural analogue data. (author)

  1. Paramagnetic centers in single-walled carbon nanotubes encapsulated with palladium and their interaction with hydrogen at H/C ≥ 1.0

    Science.gov (United States)

    Lipson, A. G.; Saunin, E. I.; Lyakhov, B. F.; Tsivadze, A. Yu.

    2008-10-01

    The nature of paramagnetic centers in a nanostructure based on single-walled carbon nanotubes (SWCNTs) encapsulated with Pd was studied by EPR spectroscopy at 77 and 293 K. It was found that strong charge-transfer π complexes of the (Pd-C x ) type, which manifested themselves as a narrow resonance (Δ H = 6 8 G and g = 2.002 at T = 77 k), were formed in the Pd-SWCNT composite along with impurity centers (Fe3O4 nanoparticles within the nanotubes), which were responsible for a broad EPR signal (Δ H = 75 G and g = 2.065 at T = 293 K). These complexes were found to be predominant adsorption sites responsible for a high gravimetric density of hydrogen (H/C ≥ 1.0) within the single-walled carbon nanotubes.

  2. Air pollution studies in terms of PM2.5, PM2.5-10, PM10, lead and black carbon in urban areas of Antananarivo - Madagascar

    CERN Document Server

    Rasoazanany, E O; Ravoson, H N; Andriambololona, Raoelina; Randriamanivo, L V; Ramaherison, H; Ahmed, H; Harinoely, M

    2012-01-01

    Atmospheric aerosols or particulate matters are chemically complex and dynamic mixtures of solid and liquid particles. Sources of particulate matters include both natural and anthropogenic processes. The present work consists in determining the concentrations of existing elements in the aerosols collected in Andravoahangy and in Ambodin'Isotry in Antananarivo city (Madagascar). The size distribution of these elements and their main sources are also studied. The Total Reflection X-Ray Fluorescence spectrometer is used for the qualitative and quantitative analyses. The results show that the concentrations of the airborne particulate matters PM2.5-10 are higher than those of PM2.5. The identified elements in the aerosol samples are Ti, Cr, Mn, Fe, Ni, Cu, Zn, Br, Sr and Pb. The average concentrations of these elements are also higher in the coarse particles than in the fine particles. The calculation of the enrichment factors by Mason's model shows that Cr, Ni, Cu, Zn, Br and Pb are of anthropogenic origins. The...

  3. Effect of C–O Bonding on the Stability and Energetics of High-Energy Nitrogen-Carbon Molecules N10C2 and N16C2

    Directory of Open Access Journals (Sweden)

    Douglas L. Strout

    2014-01-01

    Full Text Available Molecules consisting of nitrogen have been the subject of much attention due to their potential as high-energy materials. Complex molecules consisting entirely of nitrogen can be subject to rapid decomposition, and therefore other atoms are incorporated into the structure to enhance stability. Previous studies have explored the incorporation of carbon atoms into otherwise all-nitrogen cages molecules. The current study involves two such cages, N10C2 and N16C2, whose structures are derived from N12 and N18, respectively. The N10C2 and N16C2 cages in this study are modified by bonding groups O3 and CO3 to determine the effect on the relative energies between the isomers and on the thermodynamic energy release properties. Energetic trends for N10C2 and N16C2 are calculated and discussed.

  4. Effect of carbon content on carbide morphology and mechanical properties of A.R. white cast iron with 10-12% tungsten

    Energy Technology Data Exchange (ETDEWEB)

    Heydari, D. [Department of Materials Science and Engineering, Sharif University of Technology, Tehran (Iran, Islamic Republic of); Skandani, A. Alipour [Department of Engineering Science and Mechanics, Virginia Tech, Blacksburg, VA 24061 (United States); Al Haik, M., E-mail: alhaik@vt.edu [Department of Engineering Science and Mechanics, Virginia Tech, Blacksburg, VA 24061 (United States)

    2012-04-30

    Highlights: Black-Right-Pointing-Pointer Effect of W and C variation in A.R. white cast iron was studied up to 12 wt% W. It never exceeded 10 wt% in previous investigations. Black-Right-Pointing-Pointer Carbide morphologies with 2.2-3.2 wt% carbon shows that W has dominating effect on carbide morphology. Black-Right-Pointing-Pointer New carbide microstructures (GA and IA) appear in some range of carbon and its volume fraction is function of carbon content. Black-Right-Pointing-Pointer After heat treatment, new carbide morphology turns to continuous chromium carbide. Black-Right-Pointing-Pointer Wear resistance and hardness of the new alloys depends on both IA appearance presence and tungsten carbide precipitation. - Abstract: Carbide morphologies of white cast iron containing 22% Cr and 10-12% tungsten with different carbon contents (2.34-3.20 wt.%) were investigated. Results indicated that for the as-cast alloys with no heat treatments, the addition of carbon changes the morphology of carbides during air-cooling in the presence of tungsten. Light microscopy analysis revealed that for an alloy with 2.3 wt% carbon, chromium carbides possess coarse gray appearance (GA). Increasing the carbon content reduced the coarse GA zones volume fraction while a finer GA zones emerged. The coexistence of coarse and fine GA phases came to an end at 2.8 wt% carbon, at which only fine GA zones spread throughout the chromium carbide phase. Scaling up the carbon content to 3.2 wt% led to the formation of tungsten carbide and austenite in a eutectic reaction. Both fine and coarse GA zones vanished while the tungsten carbides acquired fishbone-like morphology. Upon heat treatment, the coarse GA zones vanished completely and turned into island appearance (IA) of chromium carbide. On the contrary, the finer GA zones remained unchanged after heat treatment and they coexisted with the IA. After heat treatment, the fishbone morphology shattered apart, however, the hyper chromium carbides

  5. Carbon-11 labeled papaverine as a PET tracer for imaging PDE10A: radiosynthesis, in vitro and in vivo evaluation

    International Nuclear Information System (INIS)

    Papaverine, 1-(3,4-dimethoxybenzyl)-6,7-dimethoxyisoquinoline, a specific inhibitor of phosphodiesterase (PDE) 10A with IC50 values of 36 nM for PDE10A, 1,300 nM for PDE3A and 320 nM for PDE4D, has served as a useful pharmaceutical tool to study the physiological role of PDE10A. Here, we report the radiosynthesis of [11C]papaverine and the in vitro and in vivo evaluation of [11C]papaverine as a potential positron emission tomography (PET) radiotracer for imaging PDE10A in the central nervous system (CNS). The radiosynthesis of papaverine with 11C was achieved by O-methylation of the corresponding des-methyl precursor with [11C]methyl iodide. [11C]papaverine was obtained with ∼70% radiochemical yield and a specific activity >10 Ci/μmol. In vitro autoradiography studies of rat and monkey brain sections revealed selective binding of [11C]papaverine to PDE10A enriched regions: the striatum of rat brain and the caudate and putamen of rhesus monkey brain. The biodistribution of [11C]papaverine in rats at 5 min demonstrated an initially higher accumulation in striatum than in other brain regions, however the washout was rapid. MicroPET imaging studies in rhesus macaques similarly displayed initial specific uptake in the striatum with very rapid clearance of [11C]papaverine from brain. Our initial evaluation suggests that despite papaverine's utility for in vitro studies and as a pharmaceutical tool, [11C]papaverine is not an ideal radioligand for clinical imaging of PDE10A in the CNS. Analogs of papaverine having a higher potency for inhibiting PDE10A and improved pharmacokinetic properties will be necessary for imaging this enzyme with PET.

  6. Carbon-11 labeled papaverine as a PET tracer for imaging PDE10A: radiosynthesis, in vitro and in vivo evaluation

    Energy Technology Data Exchange (ETDEWEB)

    Tu Zhude [Mallinckrodt Institute of Radiology, Washington University School of Medicine, St. Louis, MO 63110 (United States)], E-mail: tuz@mir.wustl.edu; Xu Jinbin; Jones, Lynne A.; Li Shihong; Mach, Robert H. [Mallinckrodt Institute of Radiology, Washington University School of Medicine, St. Louis, MO 63110 (United States)

    2010-05-15

    Papaverine, 1-(3,4-dimethoxybenzyl)-6,7-dimethoxyisoquinoline, a specific inhibitor of phosphodiesterase (PDE) 10A with IC{sub 50} values of 36 nM for PDE10A, 1,300 nM for PDE3A and 320 nM for PDE4D, has served as a useful pharmaceutical tool to study the physiological role of PDE10A. Here, we report the radiosynthesis of [{sup 11}C]papaverine and the in vitro and in vivo evaluation of [{sup 11}C]papaverine as a potential positron emission tomography (PET) radiotracer for imaging PDE10A in the central nervous system (CNS). The radiosynthesis of papaverine with {sup 11}C was achieved by O-methylation of the corresponding des-methyl precursor with [{sup 11}C]methyl iodide. [{sup 11}C]papaverine was obtained with {approx}70% radiochemical yield and a specific activity >10 Ci/{mu}mol. In vitro autoradiography studies of rat and monkey brain sections revealed selective binding of [{sup 11}C]papaverine to PDE10A enriched regions: the striatum of rat brain and the caudate and putamen of rhesus monkey brain. The biodistribution of [{sup 11}C]papaverine in rats at 5 min demonstrated an initially higher accumulation in striatum than in other brain regions, however the washout was rapid. MicroPET imaging studies in rhesus macaques similarly displayed initial specific uptake in the striatum with very rapid clearance of [{sup 11}C]papaverine from brain. Our initial evaluation suggests that despite papaverine's utility for in vitro studies and as a pharmaceutical tool, [{sup 11}C]papaverine is not an ideal radioligand for clinical imaging of PDE10A in the CNS. Analogs of papaverine having a higher potency for inhibiting PDE10A and improved pharmacokinetic properties will be necessary for imaging this enzyme with PET.

  7. The silicate model and carbon rich model of CoRoT-7b, Kepler-9d and Kepler-10b

    OpenAIRE

    Gong, Yan-Xiang; Zhou, Ji-Lin

    2012-01-01

    Possible bulk compositions of the super-Earth exoplanets, CoRoT-7b, Kepler-9d, and Kepler-10b are investigated by applying a commonly used silicate and a non-standard carbon model. Their internal structures are deduced using the suitable equation of state of the materials. The degeneracy problems of their compositions can be partly overcome, based on the fact that all three planets are extremely close to their host stars. By analyzing the numerical results, we conclude: 1) The iron core of Co...

  8. Heat of Mixing and Solution of Dimethyl sulfoxide C2H6OS + C5H10O3 Diethyl carbonate (HMSD1111, LB4315_H)

    Science.gov (United States)

    Cibulka, I.; Fontaine, J.-C.; Sosnkowska-Kehiaian, K.; Kehiaian, H. V.

    This document is part of Subvolume C 'Binary Liquid Systems of Nonelectrolytes III' of Volume 26 'Heats of Mixing, Vapor-Liquid Equilibrium, and Volumetric Properties of Mixtures and Solutions' of Landolt-Börnstein Group IV 'Physical Chemistry'. It contains the Chapter 'heat of Mixing and Solution of Dimethyl sulfoxide C2H6OS + C5H10O3 Diethyl carbonate (HMSD1111, LB4315_H)' providing data from direct low-pressure calorimetric measurement of molar excess enthalpy at variable mole fraction and constant temperature.

  9. Volumetric Properties of the Mixture Dimethyl sulfoxide C2H6OS + C5H10O3 Diethyl carbonate (VMSD1111, LB5134_V)

    Science.gov (United States)

    Cibulka, I.; Fontaine, J.-C.; Sosnkowska-Kehiaian, K.; Kehiaian, H. V.

    This document is part of Subvolume C 'Binary Liquid Systems of Nonelectrolytes III' of Volume 26 'Heats of Mixing, Vapor-Liquid Equilibrium, and Volumetric Properties of Mixtures and Solutions' of Landolt-Börnstein Group IV 'Physical Chemistry'. It contains the Chapter 'Volumetric Properties of the Mixture Dimethyl sulfoxide C2H6OS + C5H10O3 Diethyl carbonate (VMSD1111, LB5134_V)' providing data from direct low-pressure measurement of mass density at variable mole fraction and constant temperature, in the single-phase region(s).

  10. Volumetric Properties of the Mixture Dimethyl sulfoxide C2H6OS + C5H10O3 Diethyl carbonate (VMSD1212, LB5137_V)

    Science.gov (United States)

    Cibulka, I.; Fontaine, J.-C.; Sosnkowska-Kehiaian, K.; Kehiaian, H. V.

    This document is part of Subvolume C 'Binary Liquid Systems of Nonelectrolytes III' of Volume 26 'Heats of Mixing, Vapor-Liquid Equilibrium, and Volumetric Properties of Mixtures and Solutions' of Landolt-Börnstein Group IV 'Physical Chemistry'. It contains the Chapter 'Volumetric Properties of the Mixture Dimethyl sulfoxide C2H6OS + C5H10O3 Diethyl carbonate (VMSD1212, LB5137_V)' providing data by calculation of molar excess volume from low-pressure density measurements at variable mole fraction and constant temperature.

  11. Highly selective uptake of carbon dioxide on the zeolite |Na10.2KCs0.8|-LTA- a possible sorbent for biogas upgrading.

    Science.gov (United States)

    Cheung, Ocean; Wardecki, Dariusz; Bacsik, Zoltán; Vasiliev, Petr; McCusker, Lynne B; Hedin, Niklas

    2016-06-28

    The|Na10.2KCs0.8|8[Al12Si12O48]8(Fm3[combining macron]c)-LTA zeolite adsorbs CO2-over-CH4 with a high selectivity (over 1500). The uptake of carbon dioxide is also high (3.31 mmol g(-1), 293 K, 101 kPa). This form of zeolite A is a very promising adsorbent for applications such as biogas upgrading, where keeping the adsorption of methane to a minimum is crucial. PMID:27251457

  12. Infield superconductivity of carbon nanotubes-Cu0.5Tl0.5Ba2Ca2Cu3O10−δ superconductor composites

    Directory of Open Access Journals (Sweden)

    M. Mumtaz

    2015-10-01

    Full Text Available We investigated the infield superconducting properties of carbon nanotubes-Cu0.5Tl0.5Ba2Ca2Cu3O10−δ superconductor {(CNTsx-(CuTl-1223}; x = 0∼7 wt.% composites. The zero resistivity critical temperature {Tc(0}, critical superconducting onset transition temperature {Tconset(K} and glass transition temperature (Tg have been shifted towards lower values after the addition of carbon nanotubes (CNTs. The double transitions for all concentration of CNTs have indicated the existence of vortex-glass phase. The significant resistive broadening {ΔT = Tconset(K-Tc(0} has been observed with increasing values of external applied magnetic field. The more increasing trend in resistive broadening has also been observed after the addition of CNTs in CuTl-1223 matrix. The magnetic field dependent activation energy Uo (H has been calculated according to thermally activated flux flow (TAFF model. The overall decreasing rate in pinning energy could be due to diffusion of carbon across the grain-boundaries.

  13. The silicate and carbon-rich models of CoRoT-7b, Kepler-9d and Kepler-10b

    Institute of Scientific and Technical Information of China (English)

    Yan-Xiang Gong; Ji-Lin Zhout

    2012-01-01

    Possible bulk compositions of the super-Earth exoplanets CoRoT-7b,Kepler-9d,and Kepler-10b are investigated by applying a commonly used silicate model and a non-standard carbon model.Their internal structures are deduced using a suitable equation of state for the materials.The degeneracy problems of their compositions can be partly overcome,based on the fact that all three planets are extremely close to their host stars.By analyzing the numerical results,we conclude:1) the iron core of CoRoT-7b is not more than 27% of its total mass within lσ mass-radius error bars,so an Earth-like composition is less likely,but its carbon rich model can be compatible with an Earth-like core/mantle mass fraction; 2) Kepler-10b is more likely to have a Mercury-like composition,with its old age implying that its high iron content may be a result of strong solar wind or giant impact; 3) the transiting-only super-Earth Kepler-9d is also discussed.Combining its possible composition with the formation theory,we can place some constraints on its mass and bulk composition.

  14. 9,10-Dibromo-N-aryl-9,10-dihydro-9,10-[3,4]epipyrroloanthracene-12,14-diones: Synthesis and Investigation of Their Effects on Carbonic Anhydrase Isozymes I, II, IX, and XII.

    Science.gov (United States)

    Göksu, Haydar; Topal, Meryem; Keskin, Ali; Gültekin, Mehmet S; Çelik, Murat; Gülçin, İlhami; Tanc, Muhammet; Supuran, Claudiu T

    2016-06-01

    N-substituted maleimides were synthesized from maleic anhydride and primary amines. 1,4-Dibromo-dibenzo[e,h]bicyclo-[2,2,2]octane-2,3-dicarboximide derivatives (4a-f) were prepared by the [4+2] cycloaddition reaction of dibromoanthracenes with the N-substituted maleimide derivatives. The carbonic anhydrase (CA, EC 4.2.1.1) inhibitory effects of the new derivatives were assayed against the human (h) isozymes hCA I, II, IX, and XII. All tested bicyclo dicarboximide derivatives exhibited excellent inhibitory effects in the nanomolar range, with Ki values in the range of 117.73-232.87 nM against hCA I and of 69.74-111.51 nM against hCA II, whereas they were low micromolar inhibitors against hCA IX and XII. PMID:27174792

  15. Changing Rule of Carbon-Enriched Zone and Diffusion Behavior of Carbon in Aging 0Cr6Mn13Ni10MoTi/1Cr5Mo Dissimilar Welded Joints

    Institute of Scientific and Technical Information of China (English)

    Zheng LIU; Ligang WANG; Lai WANG

    2004-01-01

    The microstructures, the changing rule of carbon-enriched zone, the diffusion behaviors of elements C and Cr, and the carbide type of 0Cr6Mn13Ni10MoTi/1Cr5Mo dissimilar welded joints after aging at 500℃ for various times and after long-term service in technical practice were investigated by using the optical microscopy, electron probe microanalysis, scanning electron microscopy (SEM), and transmission electron microscopy (TEM). The results show that in aging 0Cr6Mn13Ni10MoTi/1Cr5Mo dissimilar welded joints, the main carbides are M3C and a few carbides are M7C3 and M23C6. The M3C carbide decomposition and dissolution with increasing aging time or aging temperature and the anti-diffusion of C and Cr cause the decrease and disappearance of the carbon-enriched zone. The results are different from those of the A302/1Cr5Mo dissimilar welded joints in previous studies.

  16. Exhaustive Analysis of a Genotype Space Comprising 10(15 )Central Carbon Metabolisms Reveals an Organization Conducive to Metabolic Innovation.

    OpenAIRE

    Sayed-Rzgar Hosseini; Aditya Barve; Andreas Wagner

    2015-01-01

    All biological evolution takes place in a space of possible genotypes and their phenotypes. The structure of this space defines the evolutionary potential and limitations of an evolving system. Metabolism is one of the most ancient and fundamental evolving systems, sustaining life by extracting energy from extracellular nutrients. Here we study metabolism's potential for innovation by analyzing an exhaustive genotype-phenotype map for a space of 10(15) metabolisms that encodes all possible su...

  17. Sex Differences in Panic-Relevant Responding to a 10% Carbon Dioxide-Enriched Air Biological Challenge

    OpenAIRE

    Nillni, Yael I.; Berenz, Erin C.; Kelly J. Rohan; Zvolensky, Michael J.

    2011-01-01

    The current study examined sex differences in psychological (i.e., self-reported anxiety, panic symptoms, and avoidance) and physiological (i.e., heart rate and skin conductance level) response to, and recovery from, a laboratory biological challenge. Participants were a community-recruited sample of 128 adults (63.3% women; Mage = 23.2 years, SD = 8.9) who underwent a 4-minute 10% CO2-enriched air biological challenge. As predicted, women reported more severe physical panic symptoms and avoi...

  18. An integrated Dissolved Organic Carbon Dynamics Model (DOCDM 1.0): model development and a case study in the Alaskan Yukon River Basin

    Science.gov (United States)

    Lu, X.; Zhuang, Q.

    2015-12-01

    Quantitative understanding of the variation in dissolved organic carbon (DOC) is important to studying the terrestrial ecosystem carbon cycle. This study presents a process-based, dissolved organic carbon dynamics model (DOCDM 1.0) that couples the soil heat conduction, water flow, DOC production, mineralization and transport in both surface and subsurface of soil profile to quantify DOC dynamics in boreal terrestrial ecosystems. The model is first evaluated and then applied for a watershed in Alaska to investigate its DOC production and transport. We find that 42 and 27 % of precipitation infiltrates to soils in 2004, a warmer year, and in 1976, a colder year, respectively. Under warming conditions, DOC transported via overland flow does not show the expected decrease trend while the overland DOC yield shows a 4 % increase. The horizontal subsurface flow only accounts for 1-2 % of total water flux, but transports 30-50 % of DOC into rivers. Water flush due to water infiltration controls DOC transport. Snowmelt plays a noticeable role in DOC flush-out and DOC transport significantly depends on flowpaths in the study region. High soil temperature stimulates DOC production. The overland DOC export does not necessarily follow the DOC downward trend in surface water transport. Overall, this study shows that DOC export behavior is complex under changing temperature and hydrological conditions in cold-region watersheds. To adequately quantify DOC dynamics in northern high latitudes, more DOC and hydrological data are needed to better parameterize and test the developed model before extrapolating it to the region.

  19. An integrated Dissolved Organic Carbon Dynamics Model (DOCDM 1.0: model development and a case study in the Alaskan Yukon River Basin

    Directory of Open Access Journals (Sweden)

    X. Lu

    2015-12-01

    Full Text Available Quantitative understanding of the variation in dissolved organic carbon (DOC is important to studying the terrestrial ecosystem carbon cycle. This study presents a process-based, dissolved organic carbon dynamics model (DOCDM 1.0 that couples the soil heat conduction, water flow, DOC production, mineralization and transport in both surface and subsurface of soil profile to quantify DOC dynamics in boreal terrestrial ecosystems. The model is first evaluated and then applied for a watershed in Alaska to investigate its DOC production and transport. We find that 42 and 27 % of precipitation infiltrates to soils in 2004, a warmer year, and in 1976, a colder year, respectively. Under warming conditions, DOC transported via overland flow does not show the expected decrease trend while the overland DOC yield shows a 4 % increase. The horizontal subsurface flow only accounts for 1–2 % of total water flux, but transports 30–50 % of DOC into rivers. Water flush due to water infiltration controls DOC transport. Snowmelt plays a noticeable role in DOC flush-out and DOC transport significantly depends on flowpaths in the study region. High soil temperature stimulates DOC production. The overland DOC export does not necessarily follow the DOC downward trend in surface water transport. Overall, this study shows that DOC export behavior is complex under changing temperature and hydrological conditions in cold-region watersheds. To adequately quantify DOC dynamics in northern high latitudes, more DOC and hydrological data are needed to better parameterize and test the developed model before extrapolating it to the region.

  20. Bombardment of SiC by 10 keV H+: carbon deposition, surface swelling and changes in surface morphology

    International Nuclear Information System (INIS)

    SiC surfaces were bombarded by H+ at 10 keV to total doses ranging from 0.7 to 25 C/cm2 in both high and ultra high vacuum environments. In the former, carbonaceous deposits were observed optically and with AES and electron microprobe analysis. The thickness of these deposits (determined by surface profilometry) increased up to a dose of 3 C/cm2 then remained constant. Surface features were observed on these deposits using SEM. In UHV, no deposit was formed, however surface swelling was observed. Surface features were again observed but were qualitatively different than those observed on the carbonaceous deposits. Several possible explanations for these observations are discussed including, in the case of the carbonaceous deposits, a possible phase change from amorphous to ordered occurring in the vicinity of a 3 C/cm2 dose. (Auth.)

  1. Penetration of Hydrogen clusters from 10 to 120 kev/u in carbon foils. Study of their slowing-down and charge distribution of emerging fragments

    International Nuclear Information System (INIS)

    This work is devoted to the experimental study of the interaction between fast (10 to 120 keV/p) hydrogen clusters with thin solid targets. First, we have studied the slowing-down of Hn+(2≤n≤21) clusters through carbon foils. Up to date this had been made only with molecular ions. We obtain evidence for vicinage effects on the energy loss of proton-clusters. We show that for projectile energies larger than 50 keV/p, the energy loss of a proton in a cluster is enhanced when compared to that of an isolated proton of the same velocity. At lower incident energies, it is a decrease of the energy loss which is observed. The same effect is also observed in the energy lost in the entrance window of a surface barrier detector bombarded by clusters. This phenomenon is interpreted in terms of interferences between individual polarisation wakes induced by each proton of the cluster. In the second part, we propose an accurate method to study the charge state of the atomic fragments resulting from the dissociation of fast Hn+ (2≤n≤15) clusters through a carbon foil. This method gives also the distribution of the neutral atoms among the emerging fragments. These distributions are finally compared with binomial laws expected from independent particles

  2. First principle study of magnetic and electronic properties of single X (X = Al, Si) atom added to small carbon clusters (C n X, n = 2-10)

    Science.gov (United States)

    Afshar, M.; Hoseini, S. S.; Sargolzaei, M.

    2016-07-01

    In this paper, the magnetic and electronic properties of single aluminum and silicon atom added to small carbon clusters (C n X; X = Al, Si; n = 2-10) are studied in the framework of generalized-gradient approximation using density functional theory. The calculations were performed for linear, two dimensional and three dimensional clusters based on full-potential local-orbital (FPLO) method. The total energies, HOMO-LUMO energy gap and total magnetic moments of the most stable structures are presented in this work. The calculations show that C n Si clusters have more stability compared to C n Al clusters. In addition, our magnetic calculations were shown that the C n Al isomers are magnetic objects whereas C n Si clusters are nonmagnetic objects.

  3. Carbon steel protection in G.S. (Girlder sulfide) heavy water fabrication plants. Control of iron content at the final stage of passivation. Pt. 10

    International Nuclear Information System (INIS)

    This paper is part of a series which corresponds to the carbon steel behaviour as construction material for Girlder sulfide (G.S.) heavy water plants. The present work analyses the iron concentration study during passivation in the passivating fluid. At the beginning, during the formation of the most soluble sulfide -that is the mackinawite-, the iron concentration reaches more than 10 ppm. After some days, this iron concentration begins to decrease up to its stabilization under 0.1 ppm. This process, which occurs in the 9th. and 11th days, indicates that passivation is over, and that a pyrite and pyrrhotite-pyrite layer exists on the iron. Some differences exist between the results obtained and those previsible for the iron sulfides solubilities. In spite of these difficulties, the procedure is perfectly adequate to judge the passivation final stage. (Author)

  4. The Distribution of Radioactivity in the Mouse Following Administration of Dibenzanthracene Labeled in the 9 and 10 Positions with Carbon Fourteen

    Energy Technology Data Exchange (ETDEWEB)

    Heidelberger, Charles; Jones, Hardin, B.

    1948-01-30

    Dibenzanthracene, labeled in the 9 and 10 positions with carbon fourteen has been administered to mice intravenously and by stomach tube as an aqueous colloid, and intraperitoneally, subcutaneously, and by stomach tube in tricaprylin solution. The distribution of radioactivity in the mice at various time intervals after administration of the carcinogen has been determined. The radioactivity is rapidly eliminated, largely through the feces, and ordinarily very little is absorbed. The distribution and rate of elimination depends upon the mode of administration. There is an appreciable quantity of radioactivity in tumors produced several months after a single subcutaneous injection of dibenzanthracene. There appear to be no detectable effects from the radiation of the labeled carcinogen.

  5. Novel chemoresistive CH4 sensor with 10 ppm sensitivity based on multiwalled carbon nanotubes functionalized with SnO2 nanocrystals

    International Nuclear Information System (INIS)

    Chemoresistive sensors based on multiwalled carbon nanotubes (MWCNTs) functionalized with SnO2 nanocrystals (NCs) have great potential for detecting trace gases at low concentrations (single ppm levels) at room temperature, because the SnO2 nanocrystals act as active sites for the chemisorption of gas molecules, and carbon nanotubes (CNTs) act as an excellent current carrying platform, allowing the adsorption of gas on SnO2 to modulate the resistance of the CNTs. However, uniform conjugation of SnO2 NCs with MWCNTs is challenging. An effective atomic layer deposition based approach to functionalize the surface of MWCNTs with SnO2 NCs, resulting in a novel CH4 sensor with 10 ppm sensitivity, is presented in this paper. Scanning electron microscopy, transmission electron microscopy (TEM), energy dispersive x-ray spectroscopy, and Raman spectroscopy were implemented to study the morphology, elemental composition, and the crystal quality of SnO2 functionalized MWCNTs. High resolution TEM images showed that the crystal quality of the functionalizing SnO2 NCs was of high quality with clear lattice fringes and the dimension almost three times smaller than shown thus far in literature. A lift-off based photolithography technique comprising bilayer photoresists was optimized to fabricate SnO2 functionalized MWCNTs-based chemoresistor sensor, which at room temperature can reliably sense below 10 ppm of CH4 in air. Such low level gas sensitivity, with significant reversible relative resistance change, is believed to be the direct result of the successful functionalization of the MWCNT surface by SnO2 NCs

  6. Novel chemoresistive CH{sub 4} sensor with 10 ppm sensitivity based on multiwalled carbon nanotubes functionalized with SnO{sub 2} nanocrystals

    Energy Technology Data Exchange (ETDEWEB)

    Humayun, Md Tanim; Paprotny, Igor, E-mail: paprotny@uic.edu [Department of Electrical and Computer Engineering, University of Illinois, Chicago, Illinois 60607 (United States); Divan, Ralu; Liu, Yuzi [Center for Nanoscale Materials, Argonne National Laboratory, Lemont, Illinois 60439 (United States); Gundel, Lara [Lawrence Berkeley National Laboratory, Berkeley, California 94720 (United States); Solomon, Paul A. [U.S. Environmental Protection Agency, Las Vegas, Nevada 89199 (United States)

    2016-01-15

    Chemoresistive sensors based on multiwalled carbon nanotubes (MWCNTs) functionalized with SnO{sub 2} nanocrystals (NCs) have great potential for detecting trace gases at low concentrations (single ppm levels) at room temperature, because the SnO{sub 2} nanocrystals act as active sites for the chemisorption of gas molecules, and carbon nanotubes (CNTs) act as an excellent current carrying platform, allowing the adsorption of gas on SnO{sub 2} to modulate the resistance of the CNTs. However, uniform conjugation of SnO{sub 2} NCs with MWCNTs is challenging. An effective atomic layer deposition based approach to functionalize the surface of MWCNTs with SnO{sub 2} NCs, resulting in a novel CH{sub 4} sensor with 10 ppm sensitivity, is presented in this paper. Scanning electron microscopy, transmission electron microscopy (TEM), energy dispersive x-ray spectroscopy, and Raman spectroscopy were implemented to study the morphology, elemental composition, and the crystal quality of SnO{sub 2} functionalized MWCNTs. High resolution TEM images showed that the crystal quality of the functionalizing SnO{sub 2} NCs was of high quality with clear lattice fringes and the dimension almost three times smaller than shown thus far in literature. A lift-off based photolithography technique comprising bilayer photoresists was optimized to fabricate SnO{sub 2} functionalized MWCNTs-based chemoresistor sensor, which at room temperature can reliably sense below 10 ppm of CH{sub 4} in air. Such low level gas sensitivity, with significant reversible relative resistance change, is believed to be the direct result of the successful functionalization of the MWCNT surface by SnO{sub 2} NCs.

  7. Crossed-Wire Laser Microwelding of Pt-10 Pct Ir to 316 Low-Carbon Vacuum Melted Stainless Steel: Part I. Mechanism of Joint Formation

    Science.gov (United States)

    Zou, G. S.; Huang, Y. D.; Pequegnat, A.; Li, X. G.; Khan, M. I.; Zhou, Y.

    2012-04-01

    The excellent biocompatibility and corrosion properties of Pt alloys and 316 low-carbon vacuum melted (LVM) stainless steel (SS) make them attractive for biomedical applications. With the increasing complexity of medical devices and in order to lower costs, the challenge of joining dissimilar materials arises. In this study, laser microwelding (LMW) of crossed Pt-10 pct Ir to 316 LVM SS wires was performed and the weldability of these materials was determined. The joint geometry, joining mechanism, joint breaking force (JBF), and fracture modes were investigated using optical microscopy, scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX), and microtensile testing. It was shown that the mechanisms of joint formation transitioned from (1) brazing, (2) a combination of brazing and fusion welding, and (3) fusion welding with increasing pulsed laser energy. The joints demonstrated various tensile failure modes including (1) interfacial failure below a peak power of 0.24 kW, (2) partial interfacial failure that propagated into the Pt-Ir wire, (3) failure in the Pt-Ir wire, and (4) failure in the SS wire due to porosity and severe undercutting caused by overwelding. During this study, the optimal laser peak power range was identified to produce joints with good joint geometry and 90 pct of the tensile strength of the Pt-10 pct Ir wire.

  8. Multiwalled Carbon Nanotubes-Dispersive Solid-Phase Extraction Coupled with UPLC-ESI-MS-MS for Simultaneous Determination of 10 Illegal Adulterants in Antihypertensive Functional Foods.

    Science.gov (United States)

    Hu, Jielan; Zeng, Li; He, Ling; You, Fan; Sun, Chengjun

    2016-05-01

    A reliable method for simultaneous determination of 10 illegal adulterants including chlortalidone, hydrochlorothiazide, indapamide, metoprolol, nifedipine, nimodipine, nitrendipine, reserpine, triamterene and valsartan in antihypertensive functional foods by ultra-high-performance liquid chromatography coupled with electrospray ionization-tandem mass spectrometry is presented in this article. The target chemicals were extracted with acetonitrile ultrasonically and cleaned up using multiwalled carbon nanotubes-dispersive solid-phase extraction. The separation was performed on a Waters ACQUITY UPLC BEH C18 Column (2.1 × 100 mm, 1.7 µm) with acetonitrile, 0.1% formic acid and 10 mmol/L ammonium acetate solution as mobile phase at a flow rate of 0.2 mL/min. Multiple reaction monitoring was applied for detection and sildenafil was used as the internal standard. The correlation coefficients of the method were >0.995, with the limits of detection of 0.022-0.30 ng/mL and the limits of quantification of 0.075-0.99 ng/mL. The interday and intraday relative standard deviations were <9.77% and the recoveries were in the range of 85.8-109%. The established method has been applied for the analysis of real samples, and reserpine was detected in a tonic wine sample with a content of 60.1 ± 3.2 mg/L. PMID:26850731

  9. Accuracy of a rapid 10-minute carbon-14 urea breath test for the diagnosis of Helicobacter pylori-associated peptic ulcer disease

    International Nuclear Information System (INIS)

    Urease in the human gastric mucosa is a marker for infection with Helicobacter pylori (HP), an organism which is associated with peptic ulcer disease. To detect gastric urease, we examined 184 patients (144 males, 40 females; mean age: 49.8±15.6 years) with suspected peptic ulcer disease. Fasting patients were given orally 5 μCi of carbon-14 labelled urea. For each patient only one breath sample was collected in hyamine at 10 min. The amount of 14C collected at 10 min was expressed as follows: [(DPM/mmol CO2 collected)/(DPM administered)]x100xbody weight (kg). The presence of HP colonization was determined by examination of multiple endoscopic prepyloric antral biopsy specimens subjected to culture or a rapid urease test. For the purpose of this study, HP-positive patients were defined as those with characteristic bacteria as indicated by a positive result of either the culture or the rapid urease test; HP-negative patients were defined as those with negative findings on both the culture and the rapid urease test. Of the 184 cases, 99 (53.8%) were positive for HP infection, and 85 (46.2%), negative. The sensitivity and specificity of the rapid 10 min 14C-urea breath test for the diagnosis of HP-associated peptic ulcer disease were evaluated by a receiver operating characteristic (ROC) curve with a variable cut-off value from 1.5 to 4.5. When a cut-off value of 1.5 was selected, the sensitivity was 100% and the specificity, 83.5%; when a cut-off value of 4.5 was selected, the sensitivity was 54.5% and the specificity, 97.6%. (orig.)

  10. Accuracy of a rapid 10-minute carbon-14 urea breath test for the diagnosis of Helicobacter pylori-associated peptic ulcer disease

    Energy Technology Data Exchange (ETDEWEB)

    Kao Chiahung (Taichung Veterans General Hospital (Taiwan, Province of China). Dept. of Nuclear Medicine); Wang Shyhjen (Taichung Veterans General Hospital (Taiwan, Province of China). Dept. of Nuclear Medicine); Hsu Chungyuan (Taichung Veterans General Hospital (Taiwan, Province of China). Dept. of Nuclear Medicine); Lin Wanyu (Taichung Veterans General Hospital (Taiwan, Province of China). Dept. of Nuclear Medicine); Huang Chihkua (Taichung Veterans General Hospital (Taiwan, Province of China). Dept. of Gastroenterology); Chen Granhum (Taichung Veterans General Hospital (Taiwan, Province of China). Dept. of Gastroenterology)

    1993-08-01

    Urease in the human gastric mucosa is a marker for infection with Helicobacter pylori (HP), an organism which is associated with peptic ulcer disease. To detect gastric urease, we examined 184 patients (144 males, 40 females; mean age: 49.8[+-]15.6 years) with suspected peptic ulcer disease. Fasting patients were given orally 5 [mu]Ci of carbon-14 labelled urea. For each patient only one breath sample was collected in hyamine at 10 min. The amount of [sup 14]C collected at 10 min was expressed as follows: (DPM/mmol CO[sub 2] collected)/(DPM administered)x100xbody weight (kg). The presence of HP colonization was determined by examination of multiple endoscopic prepyloric antral biopsy specimens subjected to culture or a rapid urease test. For the purpose of this study, HP-positive patients were defined as those with characteristic bacteria as indicated by a positive result of either the culture or the rapid urease test; HP-negative patients were defined as those with negative findings on both the culture and the rapid urease test. Of the 184 cases, 99 (53.8%) were positive for HP infection, and 85 (46.2%), negative. The sensitivity and specificity of the rapid 10 min [sup 14]C-urea breath test for the diagnosis of HP-associated peptic ulcer disease were evaluated by a receiver operating characteristic (ROC) curve with a variable cut-off value from 1.5 to 4.5. When a cut-off value of 1.5 was selected, the sensitivity was 100% and the specificity, 83.5%; when a cut-off value of 4.5 was selected, the sensitivity was 54.5% and the specificity, 97.6%. (orig.)

  11. High soil solution carbon und nitrogen concentrations in a drained Atlantic bog are reduced to natural levels by 10 yr of rewetting

    Directory of Open Access Journals (Sweden)

    S. Frank

    2013-10-01

    Full Text Available Artificial drainage of peatlands causes dramatic changes in the release of greenhouse gases and in the export of dissolved carbon (C and nutrients to downstream ecosystems. Rewetting anthropogenically altered peatlands offers a possibility to reduce nitrogen (N and C losses. In this study, we investigate the impact of drainage and rewetting on the cycling of dissolved C and N as well as on dissolved gases over a period of 1 yr and 4 month, respectively. The peeper technique was used to receive a high vertical sampling resolution. Within one Atlantic bog complex a near natural site, two drained grasslands sites with different mean water table positions, and a former peat cutting area rewetted 10 yr ago were chosen. Our results clearly indicate that drainage increased the concentration of dissolved organic carbon (DOC, ammonia, nitrate and dissolved organic nitrogen (DON compared to the near natural site. Drainage depth further determined the release and therefore the concentration level of DOC and N species, but the biochemical cycling and therefore dissolved organic matter (DOM quality and N species composition were unaffected. Thus, especially deep drainage can cause high DOC losses. In general, DOM at drained sites was enriched in aromatic moieties as indicated by SUVA280 and showed a higher degradation status (lower DOC to DON ratio compared to the near natural site. At the drained sites, equal C to N ratios of uppermost peat layer and DOC to DON ratio of DOM in soil solution suggest that the uppermost degraded peat layer is the main source of DOM. Nearly constant DOC to DON ratios and SUVA280 values with depth furthermore indicated that DOM moving downwards through the drained sites remained largely unchanged. DON and ammonia contributed most to the total dissolved nitrogen (TN. The subsoil concentrations of nitrate were negligible due to strong decline in nitrate around mean water table depth. Methane production during the winter months at

  12. Intermittent chemical vapor deposition of thick electrically conductive diamond-like amorphous carbon films using i-C4H10/N2 supermagnetron plasma

    International Nuclear Information System (INIS)

    Electrically conductive diamond-like amorphous carbon (DAC) films with nitrogen (DAC:N) were deposited on Si and SiO2 wafers using the i-C4H10/N2 supermagnetron plasma chemical vapor deposition (CVD) method. Resistivity and hardness decreased with increase of upper electrode rf power (UPRF) under constant lower electrode rf power (LORF). Film thickness increased linearly to over 0.3 μm with deposition time via intermittent deposition. The film exhibited good adhesion to the substrate. Low-resistance thick films were deposited using alternating multilayer CVD at UPRF/LORFs of 1 kW/1 kW and 300 W/300 W. In the deposited alternating multiple layers, resistivity significantly decreased with the increase of H layer (1 kW/1 kW) thickness, and film thickness significantly increased with the increase of L layer (300 W/300 W) thickness. By the deposition of H/L multiple layers, a film of 2.1 μm thickness and 0.14 Ω cm resistivity was obtained

  13. Selective dispersive micro solid-phase extraction using oxidized multiwalled carbon nanotubes modified with 1,10-phenanthroline for preconcentration of lead ions.

    Science.gov (United States)

    Feist, Barbara

    2016-10-15

    A dispersive micro solid phase extraction (DMSPE) method for the selective preconcentration of trace lead ions on oxidized multiwalled carbon nanotubes (ox-MWCNTs) with complexing reagent 1,10-phenanthroline is presented. Flame and electrothermal atomic absorption spectrometry (F-AAS, ET-AAS) were used for detection. The influence of several parameters such as pH, amount of sorbent and 1,10-phenanthroline, stirring time, concentration and volume of eluent, sample flow rate and sample volume was examined using batch procedures. Moreover, effects of inorganic matrix on recovery of the determined elements were studied. The experiment shows that foreign ions did not influence on recovery of the determined element. The method characterized by high selectivity toward Pb(II) ions. Lead ions can be quantitatively retained at pH 7 from sample volume up to 400mL and then eluent completely with 2mL of 0.5molL(-1)HNO3. The detection limits of Pb was 0.26μgL(-1) for F-AAS and 6.4ngL(-1) for ET-AAS. The recovery of the method for the determined lead was better than 97% with relative standard deviation lower than 3.0%. The preconcentration factor was 200 for F-AAS and 100 for ET-AAS. The maximum adsorption capacity of the adsorbent was found to be about 350mgg(-1). The method was applied for determination of Pb in fish samples with good results. Accuracy of the method was verified using certified reference material DOLT-3 and ERM-BB186. PMID:27173531

  14. Partial pressure (or fugacity) of carbon dioxide, salinity and other variables collected from Surface underway observations using Carbon dioxide (CO2) gas analyzer, Shower head chamber equilibrator for autonomous carbon dioxide (CO2) measurement and other instruments from Marcus G. Langseth in the North Atlantic Ocean from 2014-10-04 to 2014-10-15 (NCEI Accession 0144547)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0144547 includes Surface underway data collected from Marcus G. Langseth in the North Atlantic Ocean from 2014-10-04 to 2014-10-15. These data...

  15. Partial pressure (or fugacity) of carbon dioxide, salinity and other variables collected from time series observations using Bubble type equilibrator for autonomous carbon dioxide (CO2) measurement, Carbon dioxide (CO2) gas analyzer and other instruments from MOORINGS in the North Atlantic Ocean from 2005-10-22 to 2007-10-01 (NODC Accession 0100065)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0100065 includes chemical, physical and time series data collected from MOORINGS in the North Atlantic Ocean from 2005-10-22 to 2007-10-01. These...

  16. Spatial and Temporal Trends in the Carbon, Nitrogen, and Sulfur Isotopes of Stream DOM From 10 Watersheds at the HJ Andrews Experimental Forest.

    Science.gov (United States)

    Frentress, J.; Kendall, C.; Lajtha, K.; Jones, J.

    2008-12-01

    In order to better understand sources of dissolved organic matter (DOM) in streams from the small to large watershed scales, we initiated a one-year investigation of the chemical and isotopic characteristics of DOM at the HJ Andrews Experimental Forest (HJA) in Blue River, OR. DOM is a biologically significant loss from these watersheds, but its sources (forest floor, mineral soil, riparian zones, stream biota) are debated. Traditional chemical characterizations of DOM like SUVA and FI have been useful in conceptualizing and modeling streamflow sources, however, an improved method for assessing DOM quality is needed to adequately differentiate DOM from sources within the watershed. The isotopic characterization of inorganic molecules like nitrate has provided insight to the role of subsurface and surface processes governing the production and transport of critical nutrients, and yet to date, little work has been done to examine the usefulness of isotopic characterization of organically bound nutrients. We apply the isotopic characterization approach to DOM in order to better understand DOM production, transformation, and transport to streams in a range of watershed sizes. Major questions addressed in this research are: 1) Where in the watershed does stream DOM come from? 2) How do DOM sources vary temporally? 3) How do physical attributes of the watershed mediate DOM quality? A relatively new solid-phase extraction technique using C-18 resin was used to isolate DOM in water samples from 10 watersheds, ranging in size from 10 to 6200 hectares, on 3-week intervals from May 2007 to June 2008. The modified technique allowed for small (1 Liter) sample sizes and short processing times to reduce the costs of analysis. The capacity of carbon, nitrogen and sulfur isotopic characterizations of DOM, as well as traditional methods like SUVA and C:N, to predict physical watershed attributes (i.e. mean residence time, soil depth, elevation, gradient) and land use history (timber

  17. Effects of human behavior on aggregate carbon intensity of personal transportation: comparison of 10 OECD countries for the period 1970-1993

    International Nuclear Information System (INIS)

    Since 1970, carbon emissions from personal transportation have increased in every OECD country. While declines in fuel intensity moderated growth in aggregate carbon measures, behavioral effects, such as modal shifts or declining load factors, substantially offset changes in fuel intensity when measures of carbon intensity are decomposed. In a retrospective analysis of emission trends from 1970 to 1993, the influence of fuel prices and growth in per capita income on increases in fuel consumption, mode- and fuel-switching, and load or occupancy of personal transportation are examined. Analysis of past trends suggest that future policies focusing only on fuel intensity may be insufficient to lead to continuing reductions in total carbon emissions. (Author)

  18. Processing of carbon-fiber-reinforced Zr41.2Ti13.8Cu12.5Ni10.0Be22.5 bulk metallic glass composites

    OpenAIRE

    Kim, C. P.; Busch, R.; Masuhr, A.; Choi-Yim, H.; Johnson, W. L.

    2001-01-01

    Carbon-fiber-reinforced bulk metallic glass composites are produced by infiltrating liquid Zr41.2Ti13.8Cu12.5Ni10.0Be22.5 into carbon fiber bundles with diameter of the individual fiber of 5 mum. Reactive wetting occurs by the formation of a ZrC layer around the fibers. This results in a composite with a homogeneous fiber distribution. The volume fraction of the fibers is about 50% and the density of the composite amounts to 4.0 g/cm(^3).

  19. The increasement of the properties of structural low–carbon steel 10G2FB after deformation in the intercritical temperature interval and the accelerated cooling

    OpenAIRE

    Tkach, T

    2015-01-01

    Problem definition. With an increase of construction rate the necessity of mechanical properties of structural steel improvement has arised. The development of new modes of rolling can solve the problem of increasement the properties of structural low–carbon steels.Purpose: to increase the properties of sheet metal by determining the effect of deformation in the intercritical interval (ICI) temperatures and subsequent cooling on the structure and properties of structural low–carbon low alloy ...

  20. 46 CFR 151.50-41 - Carbon disulfide (carbon bisulfide).

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 5 2010-10-01 2010-10-01 false Carbon disulfide (carbon bisulfide). 151.50-41 Section... CARGOES BARGES CARRYING BULK LIQUID HAZARDOUS MATERIAL CARGOES Special Requirements § 151.50-41 Carbon disulfide (carbon bisulfide). (a) All openings shall be in the top of the tank. (b) Loading lines...

  1. Antimony (Sb) sorption studies on zircaloy, carbon steel (CS) and magnetite coated CS (MCS) surfaces in aqueous medium at pH 10.2 and 280℃

    International Nuclear Information System (INIS)

    Antimony sorption studies on zircaloy, CS and magnetite coated carbon steel (MCS) at primary heat transport temperature (290℃) of pressurised heavy water reactor (PHWR) are of direct relevance in investigating Sb activity problem faced in Indian PHWRs. Sb impregnated PHT pump carbon bearing releases Sb to reactor core. This Sb activates, and redeposit on out-of-core surfaces and results in exposure and apparent high decontamination factors. This Sb is not amenable to normal decantation. The form and state of deposited Sb is not yet fully known. This works attempts for this

  2. Novel Chemoresistive CH4 Sensor with 10 ppm Sensitivity Based on Multi-Walled Carbon Nanotubes (MWCNTs) Functionalized with SnO2nanocrystals

    Science.gov (United States)

    Chemoresistive sensors based on multi-walled carbon nanotubes (MWCNTs)functionalized with SnO2 nanocrystals have great potential for detecting trace gases at low concentrations (single ppm levels) at room temperature, because the SnO2 nanocrystals act as active sites for the chem...

  3. Electrohemical Properties of Carbon Nanotube Paste Electrodes Modified with Redox Cationic Dyes - doi: 10.4025/actascitechnol.v34i3.15250

    Directory of Open Access Journals (Sweden)

    Juliana Maria Ramos Antônio

    2012-05-01

    Full Text Available The present work describes the electrochemical behavior of cationic dyes (methylene blue and toluidine blue as electron mediators adsorbed in the multiwall carbon nanotubes paste in 0.5 KCl at pH 7.0 by using cyclic voltammetry. Based on midpoint potential [Em = (Eap + Ecp/2] and separation of cathodic and anodic peaks (ΔE, it was not observed interaction of different eletrolytes (LiCl, KCl, BaCl2, CaCl2, NaCl, NaNO3, Na2SO4 and NaClO4, with the cationic dyes by an ion exchange reaction and, as a consequence, absence of leaching of cationic dyes to the solution phase.  The kinetics of electron transfer on the surface electrode was not sufficiently fast showing a fairly resistence of carbon nanotube paste modified with the cationic dyes.  The midpoint potential and ΔE also were insentive to the pH range (4-8, confirming the protective effect of carbon nanotubes matrix, owing to strong interaction of between the latter and the nitrogen of nitrogen of cationic dyes with carbon nanotube matrix, minimizing the proton interaction under cationic dye. This result is very important for sensor/biosensor preparation, because the eletrooxidation behavior of the analyte will be only affected by its formal potencial shifting.  Carbon nanotubes proved to be an efficient solid matrix for the adsorption of mediator electron in comparison to the electrochemical behavior of free cationic dyes in solution phase.

  4. Congruent melting of calcium carbonate in a static experiment at 3500 K and 10-22 GPa: Its role in the genesis of ultradeep diamonds

    Science.gov (United States)

    Spivak, A. V.; Dubrovinskii, L. S.; Litvin, Yu. A.

    2011-08-01

    Resulting from static experiments performed to study the phase state of CaCO3, it was found that its melting is congruent at 20-22 GPa and 3500 K. The obtained experiment data show that the field of congruent melting of calcium carbonate is rather broad (form 2300 to 3500-3800 K at 20-22 GPa). However, the potential presence of a high-temperature phase boundary at which CaCO3 is decomposed into CaO and CO2 is not ruled out. The existence of a wide area of congruent melting of calcium carbonate (a common primary inclusion in diamonds of the transition zone and lower mantle of the Earth) allow one to consider deep-seated melts as potential parental media for ultradeep diamonds.

  5. Surface circulation patterns and the pathways of sea surface carbon dioxide (CO2 off northern Chile (~27.5° S between 30 and 10 kyr BP: global and/or local forcing?

    Directory of Open Access Journals (Sweden)

    R. Torres

    2010-03-01

    Full Text Available We present a reconstruction of past changes in partial pressure of CO2 (pCO2 from northern Chile (~27° S, between 10 and 30 kyr BP, based on carbon isotope composition of C37:2-alkenone. The high-pCO2 during the entire time series indicates that northern Chile upwelling system has been a permanent source of CO2 to the atmosphere. The multiproxy reconstruction suggests that the CO2 outgassing and sequestration pathways were modulated by local and global mechanisms. During global glacial conditions, an enhanced coastal upwelling forcing resulted in high-availability of deep water macronutrients and a CO2-supersaturated water column, which combined with high-inputs of iron from the continent, intensified the carbon sequestration pathway of the biological pump, through diatom biomass export. During the deglacial, a decrease in the upwelling forcing, an increment in water column stability and reduced continental inputs of iron are consistent with a larger role of calcifying organisms in the plankton assemblage in terms of carbon sequestration pathway through the carbonate system.

  6. Carbon Farming as a Carbon Negative Technology

    Science.gov (United States)

    Anderson, C.; Laird, D.; Hayes, D. J.

    2015-12-01

    Carbon farms have a pivotal role in national and international efforts to mitigate and adapt to climate change. A carbon farm in its broadest sense is one that reduces greenhouse gas (GHG) emissions or captures and holds carbon in vegetation and soils. Their capacity to remove carbon from the air and store it safely and permanently, while providing additional human and ecosystem benefits, means they could contribute significantly to national efforts to stabilize or reduce GHGs. We examine carbon farms in the context of corn and soybean production agriculture. We illustrate, using Iowa data but with relevance across United States corn and soybean production, the potential for carbon farms to reduce human GHG emissions and sequester carbon permanently at a rate that has meaningful impact on global greenhouse gas concentration. Carbon has been viewed as a next generation cash crop in Iowa for over a decade. The carbon farm perspective, however, goes beyond carbon as cash crop to make carbon the center of an entire farm enterprise. The transformation is possible through slight adjustment crop practices mixed with advances in technology to sequester carbon through biochar. We examine carbon balance of Iowa agriculture given only the combination of slight reduction in fertilizer and sequestration by biochar. We find the following. Iowa carbon farms could turn Iowa agriculture into a carbon sink. The estimated range of GHG reduction by statewide implementation of carbon farms is 19.46 to 90.27 MMt CO2-equivalent (CO2-e), while the current agricultural CO2-e emission estimate is 35.38 MMt CO2-e. Iowa carbon farm GHG reduction would exceed Iowa GHG reduction by wind energy (8.7 MMt CO2-e) and could exceed combined reductions from wind energy and corn grain ethanol (10.7 MMt CO2-e; 19.4 MMt CO2-e combined). In fact, Iowa carbon farms alone could exceed GHG reduction from national corn grain ethanol production (39.6 MMt CO2-e). A carbon price accessible to agricultural

  7. A Temperature Window for the Synthesis of Single-Walled Carbon Nanotubes by Catalytic Chemical Vapor Deposition of CH4over Mo2-Fe10/MgO Catalyst

    Directory of Open Access Journals (Sweden)

    Yu Ouyang

    2009-01-01

    Full Text Available Abstract A temperature window for the synthesis of single-walled carbon nanotubes by catalytic chemical vapor deposition of CH4over Mo2-Fe10/MgO catalyst has been studied by Raman spectroscopy. The results showed that when the temperature is lower than 750 °C, there were few SWCNTs formed, and when the temperature is higher than 950 °C, mass amorphous carbons were formed in the SWCNTs bundles due to the self-decomposition of CH4. The temperature window of SWCNTs efficient growth is between 800 and 950 °C, and the optimum growth temperature is about 900 °C. These results were supported by transmission electron microscope images of samples formed under different temperatures. The temperature window is important for large-scale production of SWCNTs by catalytic chemical vapor deposition method.

  8. Use of the optical lithography in the development of disposable carbon based electrodes - doi: 10.4025/actascitechnol.v35i1.11915

    Directory of Open Access Journals (Sweden)

    Lucilene Dornelles Mello

    2013-01-01

    Full Text Available In this study, carbon-based electrodes for disposable use were constructed using the technique of optical lithography. The process consisted in the irradiation of UV light on a layer of photosensitive resin (SU-8 50 deposited on a substrate of PVC. The pattern obtained electrode was filled with carbon paste. The electrodes were characterized by cyclic voltammetric using the reversible system Fe(CN63-/Fe(CN64- in KCl 0.1 mol L-1 and electrochemical impedance spectroscopy (EIS. The electrodes showed an E°’ = ½ (Epa + Epc » 229 (± 2 mV vs SCE (n = 4, with DEp » 235 (± 14 mV (n = 4. Other studies showed a linear behavior of the peak current (Ip both anode and cathode with v1/2, probably due to diffuse contribution and/or electron transfer kinetics of the reaction. These parameters are in accordance to with those obtained for screen-printed electrode described in the literature. The good results obtained show the suitability of the electrodes for analytical applications such as development of sensors.  

  9. Thermoluminescence characteristics of aluminium oxide doped with carbon and titanium co-doped subjected to 6 and 10 MV photon irradiations

    International Nuclear Information System (INIS)

    In this work, thermoluminescence (TL) characteristics of powder form of polycrystalline aluminium oxide doped with 0.2 atomic percentage (at%) carbon (Al2O3:C 0.2 at%) and co-doped with two different concentrations of titanium (0.1 and 0.2 at%) subjected to X-ray irradiations were studied. This study was conducted to determine the capability of Al2O3:C co-doped with titanium (Al2O3:C:Ti) for thermoluminescent dosimetry (TLD). Al2O3:C co-doped with 0.1 at% titanium sample exhibited the highest TL intensity centered at 184 deg C and a lower TL peak at 254 deg C. It has shown some good dosimetric properties and can be considered to be used as TLD. (author)

  10. Novel Biological Conversion of Hydrogen and Carbon Dioxide Directly into Biodiesel: Cooperative Research and Development Final Report, CRADA Number: CRD-10-408

    Energy Technology Data Exchange (ETDEWEB)

    Maness, P. C.

    2014-06-01

    OPX Biotechnologies, Inc. (OPX), the National Renewable Energy Laboratory (NREL), and Johnson Matthey will develop and optimize a novel, engineered microorganism that directly produces biodiesel from renewable hydrogen (H2) and carbon dioxide (CO2). The proposed process will fix CO2 utilizing H2 to generate an infrastructure-compatible, energy-dense fuel at costs of less than $2.50 per gallon, with water being produced as the primary byproduct. NREL will perform metabolic engineering on the bacterium Cupriavidus necator (formerly Ralstonia eutropha) and a techno-economic analysis to guide future scale-up work. H2 and CO2 uptakes rates will be genetically increased, production of free fatty acids will be enhanced and their degradation pathway blocked in order to meet the ultimate program goals.

  11. Extraction of Mucuna deeringiana seed oil using supercritical carbon dioxide - doi: 10.4025/actascitechnol.v35i3.13807

    Directory of Open Access Journals (Sweden)

    Vitor Augusto dos Santos Garcia

    2013-06-01

    Full Text Available The work aimed to investigate the extraction of Mucuna deeringiana seed oil using supercritical carbon dioxide as solvent, and the chemical profile of fatty acid components. The experiments were performed in a laboratory scale unit in a temperature range from 40°C to 60°C and pressure from 176.7 to 250 bar. The results indicated that particle diameter, temperature and pressure were important variables for CO2 extraction yields. The extracted oils were analyzed qualitatively and quantitatively in terms of their fatty acid compounds, and the results showed the presence of essential fatty acids. The main fatty acids were linoleic acid (about 40%, palmitic acid (about 20% and oleic acid (about 16%; approximately 5% of linolenic acid is reported. No significant differences were found in the fatty acid analysis for the range of variables investigated.

  12. Volumetric Properties of the Mixture Dimethyl carbonate C3H6O3 + C10H22O5 2,5,8,11,14-Pentaoxapentadecane (VMSD1112, LB4865_V)

    Science.gov (United States)

    Cibulka, I.; Fontaine, J.-C.; Sosnkowska-Kehiaian, K.; Kehiaian, H. V.

    This document is part of Subvolume C 'Binary Liquid Systems of Nonelectrolytes III' of Volume 26 'Heats of Mixing, Vapor-Liquid Equilibrium, and Volumetric Properties of Mixtures and Solutions' of Landolt-Börnstein Group IV 'Physical Chemistry'. It contains the Chapter 'Volumetric Properties of the Mixture Dimethyl carbonate C3H6O3 + C10H22O5 2,5,8,11,14-Pentaoxapentadecane (VMSD1112, LB4865_V)' providing data by calculation of mass density in the single-phase region(s) from low-pressure dilatometric measurements of the molar excess volume at variable mole fraction and constant temperature.

  13. Volumetric Properties of the Mixture Dimethyl carbonate C3H6O3 + C10H22O5 2,5,8,11,14-Pentaoxapentadecane (VMSD1211, LB4862_V)

    Science.gov (United States)

    Cibulka, I.; Fontaine, J.-C.; Sosnkowska-Kehiaian, K.; Kehiaian, H. V.

    This document is part of Subvolume C 'Binary Liquid Systems of Nonelectrolytes III' of Volume 26 'Heats of Mixing, Vapor-Liquid Equilibrium, and Volumetric Properties of Mixtures and Solutions' of Landolt-Börnstein Group IV 'Physical Chemistry'. It contains the Chapter 'Volumetric Properties of the Mixture Dimethyl carbonate C3H6O3 + C10H22O5 2,5,8,11,14-Pentaoxapentadecane (VMSD1211, LB4862_V)' providing data from direct low-pressure dilatometric measurement of molar excess volume at variable mole fraction and constant temperature.

  14. A Study on Production of Carbon Nanotubes by CH4 Decomposition over LaNiO3, La4Ni3O10, La3Ni2O7 and La2NiO4

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Carbon nanotubes (CNTs) of narrow size distribution can be abundantly produced in the catalytic decomposition of CH4 over pre-reduced LaNiO3, La4Ni3O10, La3Ni2O7 and La2NiO4.The CNTs obtained were characterized by means of transmission electron microscopy (TEM).Thermal oxidation of CNTs in air was monitored thermogravimetrically (TG). The resultsrevealed that a lower La/Ni ratio of the catalysts would lead to a wider diameter distribution and a higher degree of graphitic nature.

  15. Evaluation of surface energy and carbon fluxes within a large wind farm during the CWEX-10/11 Crop Wind-energy EXperiments

    Science.gov (United States)

    Rajewski, D. A.; Takle, E. S.; Prueger, J. H.; Oncley, S.; Horst, T. W.; Pfeiffer, R.; Hatfield, J.; Spoth, K. K.; Doorenbos, R.

    2012-12-01

    The Crop Wind-energy EXperiment conducted in summer 2010 (very moist conditions) and summer 2011 (abnormally dry) included measurements of wind speed, temperature, relative humidity, turbulence kinetic energy, H2O, and CO2 at stations north and south of a line of turbines at the southwest edge of a large-scale 200-turbine wind farm (prevailing wind from the south). In contrast to previous studies that have reported turbine influences on surface wind speed and temperature, this report focuses on scalar fluxes of heat, H2O, and CO2. From previous measurements in agricultural fields we recognize the importance of non-turbine factors in analysis of the flux differences: variability of soil characteristics, moisture content, crop cultivar, management practices, planting dates, etc., which can create differences in what looks like a uniform field of maize (corn). We conceptualize the influences of turbines at canopy height at a given location in the field to arise from (1) wakes of reduced wind speed and turbulence conditions different from ambient that intersect the surface, (2) wakes that are passing overhead and interrupt the ambient turbulence that scales with height, or (3) changes in static pressure upwind and downwind of lines of turbines that create small-scale pressure gradients, localized flows, and changes to the vertical exchange of scalar variables. The turbine SCADA wind speed and wind direction provided by the wind farm operator facilitated our comparison of surface fluxes upwind and downwind as wakes moved laterally throughout the day and night. We report multiple levels of evidence that wind turbines increase vertical exchange of carbon dioxide and water vapor over the canopy. Latent heat and carbon fluxes are responsive to slight changes in the turbine wake position, and the flux differences are maximized when the periphery of the wake edge is above the station. The flux stations north of the turbine line report a larger net ecosystem exchange

  16. Carbon Carbon Composites: An Overview .

    OpenAIRE

    G. Rohini Devi; K. Rama Rao

    1993-01-01

    Carbon carbon composites are a new class of engineering materials that are ceramic in nature but exhibit brittle to pseudoplastic behaviour. Carbon-carbon is a unique all-carbon composite with carbon fibre embeded in carbon matrix and is known as an inverse composite. Due to their excellent thermo-structural properties, carbon-carbon composites are used in specialised application like re-entry nose-tips, leading edges, rocket nozzles, and aircraft brake discs apart from several indust...

  17. Hydrogeology from 10,000 ft below: lessons learned in applying pulse testing for leakage detection in a carbon sequestration formation

    Science.gov (United States)

    Sun, A. Y.; Lu, J.; Hovorka, S. D.; Freifeld, B. M.; Islam, A.

    2015-12-01

    Monitoring techniques capable of deep subsurface detection are desirable for early warning and leakage pathway identification in geologic carbon storage formations. This work investigates the feasibility of a leakage detection technique based on pulse testing, which is a traditional hydrogeological characterization tool. In pulse testing, the monitoring reservoir is stimulated at a fixed frequency and the acquired pressure perturbation signals are analyzed in the frequency domain to detect potential deviations in the reservoir's frequency domain response function. Unlike traditional time-domain analyses, the frequency-domain analysis aims to minimize the interference of reservoir noise by imposing coded injection patterns such that the reservoir responses to injection can be uniquely determined. We have established the theoretical basis of the approach in previous work. Recently, field validation of this pressure-based, leakage detection technique was conducted at a CO2-EOR site located in Mississippi, USA. During the demonstration, two sets of experiments were performed using 90-min and 150-min pulsing periods, for both with and without leak scenarios. Because of the lack of pre-existing leakage pathways, artificial leakage CO2 was simulated by rate-controlled venting from one of the monitoring wells. Our results show that leakage events caused a significant deviation in the amplitude of the frequency response function, indicating that pulse testing may be used as a cost-effective monitoring technique with a strong potential for automation.

  18. 10x10

    DEFF Research Database (Denmark)

    10x10 collects personal essays by ten leading contemporary social science scholars on the ten works they each find have formed their own academic development the most. Based on the insights and experiences of people who have formed their various fields in important ways, it offers personal reviews....... These eminent scholars here describe in their own words what made a difference for them, and why the rest of us should stand up, take notice, and read these books too....

  19. Properties of carbon-based structures synthesized in nuclear reactions induced by bremsstrahlung γ quanta with threshold energy of 10 MeV at helium pressure of 1.1 kbar

    Science.gov (United States)

    Didyk, A. Yu.; Wiśniewski, R.

    2016-07-01

    Helium gas with an initial pressure of about 1.1 kbar inside a high-pressure chamber (HeHPC) has been irradiated by bremsstrahlung γ quanta with a threshold energy of 10 MeV for 1.0 × 105 s produced by an electron-beam current of 22-24 μA. After opening the HeHPC, the residual pressure of helium is equal to 430 bar. Synthesized black foils with a variety of other objects are found inside the HeHPC. They are located on the inner surfaces of the reaction chamber made of high-purity copper (99.99%), the entrance the window of γ quanta made of beryllium bronze and a copper container of nuclear and chemical reaction products. Elemental analysis with the use of scanning electron microscopy and X-ray microprobe analysis has revealed that the foils contain predominantly carbon and small quantities of other elements from carbon to iron. The results are in good agreement with the cycle of investigations of the authors devoted to the γ-quanta irradiation of dense hydrogen and helium gases in the presence (absence) of metals in a reaction chamber.

  20. Electrochemical behavior of the 1,10-phenanthroline ligand on a multiwalled carbon nanotube surface and its relevant electrochemistry for selective recognition of copper ion and hydrogen peroxide sensing.

    Science.gov (United States)

    Gayathri, Prakasam; Senthil Kumar, Annamalai

    2014-09-01

    1,10-Phenanthroline (Phen) is a well-known benchmark ligand and has often been used in the coordination chemistry for the complexation of transition metal ions, such as Fe(2+), Ni(2+), and Co(2+). Because the electro-oxidation potential of Phen is much higher (>2 V versus Ag/AgCl) than the water decomposition potential, i.e., ∼1.5 V versus Ag/AgCl, in pH 7, it is practically difficult to electro-oxidize Phen in aqueous medium using any conventional electrodes, such as glassy carbon electrode (GCE), gold, and platinum. Interestingly, herein, we report an unexpected oxidation of Phen to a highly redox active 1,10-phenanthroline-5,6-dione (Phen-dione) and its confinement on a multiwalled carbon nanotube (MWCNT)-modified glassy carbon electrode (GCE/MWCNT@Phen-dione) surface by potential cycling of Phen-adsorbed GCE/MWCNT (GCE/MWCNT@Phen) from -1 to 1 V versus Ag/AgCl in pH 7 phosphate buffer solution. GCE/MWCNT@Phen-dione showed selective recognition of copper ion (GCE/MWCNT@Phen-dione-Cu(2+)) by catalyzing the hydrogen peroxide reduction reaction in a neutral pH solution. The precise structure of the Phen electro-oxidized product has been identified after characterizing the electrode and/or ethanolic extract of the product by various techniques, such as Raman, Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS) (for copper complex), liquid chromatography-mass spectrometry (LC-MS), electrospray ionization-mass spectrometry (ESI-MS) (for copper complex), cyclic voltammetry (CV), and in situ electrochemical quartz crystal microbalance (EQCM) and comparing electrochemical behavior of several control compounds, such as phenanthrene and 9,10-phenanthrenequinone. It is concluded that the product formed is 1,10-phenanthroline-5,6-dione, wherein the dione position is ortho to each other and the copper ion is complexed with nitrogen of the phenanthroline ring. With extended electrochemical oxidation of a structurally similar ligand, 2

  1. The biomarkers of 2,6,10,15,19-pentamethylicosenes and their carbon isotopic composition in the sediments from the Gulf of Mexico

    Institute of Scientific and Technical Information of China (English)

    SONG Zhiguang; WANG Cuiping

    2006-01-01

    A group of 2,6,10,15,19-pentamethylicosenes (PMI△) containing 1-5 unsaturated double bonds has been identified in the sea floor sediments from the Gulf of Mexico at the Green Canyon 238 site.These PMI△ compounds are distributed between nC22 and nC24 on the mass chromatogram of aliphatic fraction. Their δ13C values are very much depleted in 13C and in the range of -86.7‰ to -115.5‰, whereas the δ13C values of companion n-alkanes range from -28.4‰ to -34.6‰. These unsaturated PMI△ compounds are typical biomarkers derived from the anaerobic oxidation of methane mediated by methane-oxidizing archaeal bacteria and indicative of the gas seeps or even the occurrence of gas hydrates in the deep sea sediments.

  2. Accelerating Mineral Carbonation Using Carbonic Anhydrase.

    Science.gov (United States)

    Power, Ian M; Harrison, Anna L; Dipple, Gregory M

    2016-03-01

    Carbonic anhydrase (CA) enzymes have gained considerable attention for their potential use in carbon dioxide (CO2) capture technologies because they are able to catalyze rapidly the interconversion of aqueous CO2 and bicarbonate. However, there are challenges for widespread implementation including the need to develop mineralization process routes for permanent carbon storage. Mineral carbonation of highly reactive feedstocks may be limited by the supply rate of CO2. This rate limitation can be directly addressed by incorporating enzyme-catalyzed CO2 hydration. This study examined the effects of bovine carbonic anhydrase (BCA) and CO2-rich gas streams on the carbonation rate of brucite [Mg(OH)2], a highly reactive mineral. Alkaline brucite slurries were amended with BCA and supplied with 10% CO2 gas while aqueous chemistry and solids were monitored throughout the experiments (hours to days). In comparison to controls, brucite carbonation using BCA was accelerated by up to 240%. Nesquehonite [MgCO3·3H2O] precipitation limited the accumulation of hydrated CO2 species, apparently preventing BCA from catalyzing the dehydration reaction. Geochemical models reproduce observed reaction progress in all experiments, revealing a linear correlation between CO2 uptake and carbonation rate. Data demonstrates that carbonation in BCA-amended reactors remained limited by CO2 supply, implying further acceleration is possible. PMID:26829491

  3. Beta radiation effect on catalytic activity of BASF K-3-10 catalyst in low-temperature water vapour conversion of carbon monoxide

    International Nuclear Information System (INIS)

    The CuO-ZnO-Cr2O3 based K-3-10 catalyst manufactured by BASF allows the conversion of CO with water vapour during the industrial production of hydrogen to be conducted at a relatively low temperature of 420 to 500 K. The effect of beta radiation on catalytic activity was studied in a troughflow tube reactor operating in integral mode. The effect of radiation was observed using the value of relative catalytic activity expressed as the ratio of reaction rate conctants during irradiation and without irradiation. Two cases were studied: a) preliminary irradiation of 8 samples of catalysts with a 90Sr-90Y source with doses of 1.7 to 3524 kGy, b) the incorporation of the 32P radionuclide in the catalytic bed of 6 samples such that the dose absorbed bz the catalyst during the experiment was 19.1 to 687.8 Gy. For preliminary irradiation, a non-monotonous increase was found in the catalytic activity amounting to 28 - 83 % (reaching maximum at a dose of 125.9 kGy.). Radioactive bed experiments showed a monotonous increase in catalytic activity with bed radioactivity; the highest achieved increase in activity was 72 %. Differences were found in the stability in time of radiation modified catalytic activity showing that effects induced by the two methods have a different character. A probable explanation of observed dependences is suggested. (A.K.)

  4. Effect of Carbon, Nitrogen Sources on Lipid Accumulation and Fatty Acid Composition of Monoraphidium sp.FXY-10 under Heterotrophic Cultivation%碳源、氮源对异养单针藻Monoraphidium sp.FXY-10油脂积累和脂肪酸组成的影响

    Institute of Scientific and Technical Information of China (English)

    黄力; 贺赐安; 赵鹏; 余旭亚

    2013-01-01

    Effect of carbon and nitrogen sources on heterotrophic cultivation of microalgae Monoraphidium sp. FXY-10 is studied. The biomass, oil accumulation and fatty acid composition of microalgae cell are analysed comparatively by selecting various types and setting different concentrations of carbon and nitrogen sources with BG-11 as basic medium. The results show that microalgae lipid accumulating with glucose as carbon source and sodium nitrate as nitrogen source is an ideal candidate for biodiesel production. The lipid production is not significantly impacted (P > 0. 05) by different sodium nitrate concentration which was 1. 00, 3. 00 and 5.00 g/L, respectively. Moreover, when glucose concentration is 10.00 g/L using sodium nitrate as nitrogen source, lipid production can be obtained the highest experiment value 0. 84 g/L. And the fatty acid of microalgae lipid is mainly composed of short chain saturated and monounsaturated fatty acids, such as C16= 0 and C18: 1. So they result a lower degree of unsaturation (DU) value 61.98.%研究了碳源与氮源对单针藻Monoraphidium sp.FXY-10异养培养的影响.以BG-11为基础培养基,通过添加不同类型、浓度梯度碳源和氮源,比较分析微藻生物量、油脂积累以及脂肪酸组成.结果表明,以葡萄糖作碳源,硝酸钠为氮源,微藻细胞积累的油脂是理想的生物柴油制备原料.硝酸钠浓度分别为1.00、3.00和5.00 g/L时,对油脂产量影响不显著(P>0.05).葡萄糖浓度为10.00 g/L,硝酸钠为氮源油脂产量达到实验最高值0.84 g/L,其油脂脂肪酸组成主要由C16∶0和C18∶1等短链饱和脂肪酸和单不饱和脂肪酸组成,不饱和度值(DU)为61.98,相对偏低.

  5. Carbon Monoxide Toxicity

    Science.gov (United States)

    Aniol, Michael J.

    1992-01-01

    Of all fatal poisonings in the United States, an estimated half are due to carbon monoxide. The number of non-lethal poisonings due to carbon monoxide is difficult to estimate because signs and symptoms of carbon monoxide poisoning cover a wide spectrum and mimic other disorders. Misdiagnosis is serious, as the patient often returns to the contaminated environment. Those not receiving proper treatment are at significant risk, as high as 10% to 12%, of developing late neurological sequelae. The diagnosis of carbon monoxide poisoning depends upon precise history taking, careful physical examination, and a high index of suspicion. ImagesFigure 2 PMID:21221282

  6. Force10 P10 Evaluation

    Energy Technology Data Exchange (ETDEWEB)

    Allen, J; Goldstone, R; Instenes, S; Lawver, B

    2007-06-08

    The lack of an acceptable intrusion monitoring solution limits the deployment of 10GE (10 Gigabit-per-second Ethernet) technology across the LLNL's unclassified network infrastructure. The desire to operate at 10GE motivates us to evaluate the functionality and performance of a 10GE intrusion monitoring solution, the Force10 P10.

  7. Carbon Dioxide, Hydrographic, and Chemical Data Obtained During the R/V Meteor Cruise 22/5 in the South Atlantic Ocean (WOCE Section A10, December 1992-January 1993)

    Energy Technology Data Exchange (ETDEWEB)

    Kozyr, A.

    1998-12-01

    This data documentation discusses the procedures and methods used to measure total carbon dioxide (TCO{sub 2}) and total alkalinity (TALK) at hydrographic stations, as well as the underway partial pressure of CO{sub 2} (pCO{sub 2}) during the R/V Meteor Cruise 22/5 in the South Atlantic Ocean (Section A10). Conducted as part of the World Ocean Circulation Experiment (WOCE), the cruise began in Rio de Janeiro on December 27, 1992, and ended after 36 days at sea in Capetown, South Africa, on January 31, 1993. Measurements made along WOCE Section A10 included pressure, temperature, and salinity [measured by conductivity, temperature, and depth (CTD) sensor], bottle salinity, bottle oxygen, phosphate, nitrate, nitrite, silicate, chlorofluorocarbons (CFC-1 1 , CFC-12), TCO{sub 2}, TALK, and underway pCO{sub 2}. The TCO{sub 2} was measured by using two Single-Operator Multiparameter Metabolic Analyzers (SOMMAs) for extracting CO{sub 2} from seawater samples that were coupled to a coulometer for detection of the extracted CO{sub 2}. The overall precision and accuracy of the analyses was {+-} 1.9 {micro}mol/kg. Samples collected for TALK were measured by potentiometric titration; precision was {+-}2.0 {micro}mol/kg. Underway pCO{sub 2} was measured by infrared photometry with a precision of {+-} 2.0 {micro}atm. The work aboard the R/V Meteor was supported by the U.S. Department of Energy under contract DE-AC02-76CHOO016, and the Bundesministerium fir Forschung und Technologies through grants 03F0545A and MPG 099/1.

  8. Dissolved inorganic carbon, pH, temperature, salinity and other variables collected from time series and surface observations using Moored Autonomous Dissolved Inorganic Carbon (MADIC) System, Sunburst SAMI2 pH sensor, and other instruments from Kewalo Buoy near the coast of Honolulu, Hawaii from 2013-10-31 to 2014-06-15 (NCEI Accession 0132048)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — To expand the number of tools available for autonomous carbonate system observations, we have developed a robust surface ocean dissolved inorganic carbon (DIC)...

  9. Conducting carbonized polyaniline nanotubes

    Science.gov (United States)

    Mentus, Slavko; Ćirić-Marjanović, Gordana; Trchová, Miroslava; Stejskal, Jaroslav

    2009-06-01

    Conducting nitrogen-containing carbon nanotubes were synthesized by the carbonization of self-assembled polyaniline nanotubes protonated with sulfuric acid. Carbonization was carried out in a nitrogen atmosphere at a heating rate of 10 °C min-1 up to a maximum temperature of 800 °C. The carbonized polyaniline nanotubes which have a typical outer diameter of 100-260 nm, with an inner diameter of 20-170 nm and a length extending from 0.5 to 0.8 µm, accompanied with very thin nanotubes with outer diameters of 8-14 nm, inner diameters 3.0-4.5 nm and length extending from 0.3 to 1.0 µm, were observed by scanning and transmission electron microscopies. Elemental analysis showed 9 wt% of nitrogen in the carbonized product. Conductivity of the nanotubular PANI precursor, amounting to 0.04 S cm-1, increased to 0.7 S cm-1 upon carbonization. Molecular structure of carbonized polyaniline nanotubes has been analyzed by FTIR and Raman spectroscopies, and their paramagnetic characteristics were compared with the starting PANI nanotubes by EPR spectroscopy.

  10. Conducting carbonized polyaniline nanotubes

    Energy Technology Data Exchange (ETDEWEB)

    Mentus, Slavko; Ciric-Marjanovic, Gordana [Faculty of Physical Chemistry, University of Belgrade, Studentski trg 12-16, 11158 Belgrade (Serbia); Trchova, Miroslava; Stejskal, Jaroslav [Institute of Macromolecular Chemistry, Academy of Sciences of the Czech Republic, Heyrovsky Square 2, 162 06 Prague 6 (Czech Republic)], E-mail: gordana@ffh.bg.ac.rs

    2009-06-17

    Conducting nitrogen-containing carbon nanotubes were synthesized by the carbonization of self-assembled polyaniline nanotubes protonated with sulfuric acid. Carbonization was carried out in a nitrogen atmosphere at a heating rate of 10 deg. C min{sup -1} up to a maximum temperature of 800 deg. C. The carbonized polyaniline nanotubes which have a typical outer diameter of 100-260 nm, with an inner diameter of 20-170 nm and a length extending from 0.5 to 0.8 {mu}m, accompanied with very thin nanotubes with outer diameters of 8-14 nm, inner diameters 3.0-4.5 nm and length extending from 0.3 to 1.0 {mu}m, were observed by scanning and transmission electron microscopies. Elemental analysis showed 9 wt% of nitrogen in the carbonized product. Conductivity of the nanotubular PANI precursor, amounting to 0.04 S cm{sup -1}, increased to 0.7 S cm{sup -1} upon carbonization. Molecular structure of carbonized polyaniline nanotubes has been analyzed by FTIR and Raman spectroscopies, and their paramagnetic characteristics were compared with the starting PANI nanotubes by EPR spectroscopy.

  11. Carbon isotopes in mollusk shell carbonates

    Science.gov (United States)

    McConnaughey, Ted A.; Gillikin, David Paul

    2008-10-01

    Mollusk shells contain many isotopic clues about calcification physiology and environmental conditions at the time of shell formation. In this review, we use both published and unpublished data to discuss carbon isotopes in both bivalve and gastropod shell carbonates. Land snails construct their shells mainly from respired CO2, and shell δ13C reflects the local mix of C3 and C4 plants consumed. Shell δ13C is typically >10‰ heavier than diet, probably because respiratory gas exchange discards CO2, and retains the isotopically heavier HCO3 -. Respired CO2 contributes less to the shells of aquatic mollusks, because CO2/O2 ratios are usually higher in water than in air, leading to more replacement of respired CO2 by environmental CO2. Fluid exchange with the environment also brings additional dissolved inorganic carbon (DIC) into the calcification site. Shell δ13C is typically a few ‰ lower than ambient DIC, and often decreases with age. Shell δ13C retains clues about processes such as ecosystem metabolism and estuarine mixing. Ca2+ ATPase-based models of calcification physiology developed for corals and algae likely apply to mollusks, too, but lower pH and carbonic anhydrase at the calcification site probably suppress kinetic isotope effects. Carbon isotopes in biogenic carbonates are clearly complex, but cautious interpretation can provide a wealth of information, especially after vital effects are better understood.

  12. Caracterización de Partículas Suspendidas (PST y Partículas Respirables (PM 10 producidas en Áreas de Explotación Carbonífera a Cielo Abierto Characterization of Total Suspended Particles (TSP and Inhalable Particulate Matter (PM 10 generated in Open Pit Coal Mining Areas

    Directory of Open Access Journals (Sweden)

    Luis C Angulo

    2011-01-01

    Full Text Available Se presenta una revisión de la literatura sobre la cuantificación y caracterización de partículas suspendidas (PST y partículas respirables (PM10 producidas en áreas de explotación carbonífera a cielo abierto. El material particulado es un contaminante complejo por sus características físicas (distribución de tamaño de partícula, morfología y densidad y por sus características químicas (compuestos orgánicos e inorgánicos, metales y contaminantes primarios y secundarios. Estas características son críticas para determinar el tipo y magnitud de los efectos sobre la salud humana. Se encontró que los trabajos realizados, han empleado experimentos de laboratorio y de campo, así como estudios de modelación. Esta revisión bibliográfica contribuye a una mejor comprensión y evaluación de las tecnologías que se deben usar para encontrar soluciones a este problema de contaminación.This article presents a literature review about the quantification and characterization of total suspended particles (TSP and inhalable particulate matter (PM 10 generated in open pit coal mining areas. Particle matter is a complex pollutant due to its physical characteristics (particle size distribution, morphology and density and its chemical characteristics (organic and inorganic components, metals, and primary and secondary pollutants. These characteristics are critical to determine the type and the magnitude of their effects on human health. It was found that the different works published in the literature have used lab and field experiments, and also modeling studies. This literature review contributes to improve the understanding and evaluation of technologies that must be used to find solutions to this atmospheric pollution problem.

  13. Partial pressure (or fugacity) of carbon dioxide, salinity and other variables collected from time series observations using Bubble type equilibrator for autonomous carbon dioxide (CO2) measurement, Carbon dioxide (CO2) gas analyzer and other instruments from MOORINGS in the North Pacific Ocean from 2010-09-02 to 2010-10-11 (NCEI Accession 0144245)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0144245 includes time series data collected from MOORINGS in the North Pacific Ocean from 2010-09-02 to 2010-10-11. These data include AIR-SEA...

  14. Partial pressure (or fugacity) of carbon dioxide, salinity and other variables collected from time series observations using Bubble type equilibrator for autonomous carbon dioxide (CO2) measurement, Carbon dioxide (CO2) gas analyzer and other instruments from the MOORINGS in the North Pacific Ocean from 2008-11-11 to 2010-10-11 (NODC Accession 0084098)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0084098 includes chemical, physical and time series data collected from MOORINGS in the North Pacific Ocean from 2008-11-11 to 2010-10-11. These data...

  15. Partial pressure (or fugacity) of carbon dioxide, salinity and other variables collected from time series observations using Bubble type equilibrator for autonomous carbon dioxide (CO2) measurement, Carbon dioxide (CO2) gas analyzer and other instruments from MOORINGS in the North Pacific Ocean from 2009-09-19 to 2010-10-28 (NODC Accession 0112885)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0112885 includes chemical, physical and time series data collected from MOORINGS in the North Pacific Ocean from 2009-09-19 to 2010-10-28. These data...

  16. Partial pressure (or fugacity) of carbon dioxide, salinity and other variables collected from time series observations using Bubble type equilibrator for autonomous carbon dioxide (CO2) measurement, Carbon dioxide (CO2) gas analyzer and other instruments from the MOORINGS in the Coastal Waters of SE Alaska from 2011-06-10 to 2012-09-29 (NODC Accession 0116715)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0116715 includes chemical, physical and time series data collected from MOORINGS in the Coastal Waters of SE Alaska from 2011-06-10 to 2012-09-29....

  17. Partial pressure (or fugacity) of carbon dioxide, salinity and SEA SURFACE TEMPERATURE collected from time series observations using Carbon dioxide (CO2) gas analyzer, Shower head chamber equilibrator for autonomous carbon dioxide (CO2) measurement and other instruments from Polaris II in the South Pacific Ocean from 2006-08-29 to 2006-10-24 (NODC Accession 0112883)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0112883 includes time series data collected from Polaris II in the South Pacific Ocean from 2006-08-29 to 2006-10-24. These data include Partial...

  18. Voltammetric Response of Epinephrine at Carbon Nanotube Modified Glassy Carbon Electrode and Activated Glassy Carbon Electrode

    Institute of Scientific and Technical Information of China (English)

    WANG Juan; TANG Ping; ZHAO Fa-qiong; ZENG Bai-zhao

    2005-01-01

    The electrochemical behavior of epinephrine at activated glassy carbon electrode and carbon nanotube-coated glassy carbon electrode was studied. Epinephrine could exhibit an anodic peak at about 0.2 V (vs. SCE) at bare glassy carbon electrode, but it was very small.However, when the electrode was activated at certain potential (i. e. 1.9V) or modified with carbon nanotube, the peak became more sensitive,resulting from the increase in electrode area in addition to the electrostatic attraction. Under the selected conditions, the anodic peak current was linear to epinephrine concentration in the range of 3.3 × 10-7-1.1 × 10-5mol/L at activated glassy carbon electrode and in the range of 1.0 × 10-6-5.0 × 10-5 mol/L at carbon nanotube-coated electrode. The correlation coefficients were 0. 998 and 0. 997, respectively. The determination limit was 1.0 × 10-7 mol/L. The two electrodes have been successfully applied for the determination of epinephrine in adrenaline hydrochloride injection with recovery of 95%-104%.

  19. Carbon isotope effects in carbonate systems

    Science.gov (United States)

    Deines, Peter

    2004-06-01

    Global carbon cycle models require a complete understanding of the δ 13C variability of the Earth's C reservoirs as well as the C isotope effects in the transfer of the element among them. An assessment of δ 13C changes during CO 2 loss from degassing magmas requires knowledge of the melt-CO 2 carbon isotope fractionation. In order to examine the potential size of this effect for silicate melts of varying composition, 13C reduced partition functions were computed in the temperature range 275 to 4000 K for carbonates of varying bond strengths (Mg, Fe, Mn, Sr, Ba, Pb, Zn, Cd, Li, and Na) and the polymorphs of calcite. For a given cation and a given pressure the 13C content increases with the density of the carbonate structure. For a given structure the tendency to concentrate 13C increases with pressure. The effect of pressure (‰/10 kbar) on the size of the reduced partition function of aragonite varies with temperature; in the pressure range 1 to 10 5 bars the change is given by: Δ 13C p average=-0.01796+0.06635∗ 10 3/T+0.006875∗ 10 6/T2 For calcite III the pressure effect is on average 1.4× larger than that for aragonite at all temperatures. The nature of the cation in a given structure type has a significant effect on the carbon isotope fractionation properties. The tendency to concentrate 13C declines in the series magnesite, aragonite, dolomite, strontianite, siderite, calcite, smithonite, witherite, rhodochrosite, otavite, cerrusite. For divalent cations a general expression for an estimation of the reduced partition function (β) from the reduced mass (μ = [M Cation × M Carbonate]/[M Cation + M Carbonate]) is: 1000 lnβ=(0.032367-0.072563∗ 10 3/T-0.01073∗ 10 6/T2)∗μ-14.003+29.953∗ 10 3/T+9.4610∗ 10 6/T2 For Mg-calcite the 13C content varies with the Mg concentration. The fractionation between Mg-calcite (X = mole fraction of MgCO 3) and calcite is given by: 1000 ln(α MgCalite- Calcite)=[0.013702-0.10957× 10 3/T+1.35940× 10 6/T2

  20. Carbon Research in the Czech Republic

    Czech Academy of Sciences Publication Activity Database

    Glogar, Petr

    Singapore : World Scientific, 1996 - (Palmer, K.; Marx , D.; Wright, M.), s. 421-425 [Carbon and Carbonaceous Composite Materials: Structure-Property Relationships. Malenovice (CZ), 10.10.1995-13.10.1995

  1. 46 CFR 97.37-9 - Carbon dioxide alarm.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 4 2010-10-01 2010-10-01 false Carbon dioxide alarm. 97.37-9 Section 97.37-9 Shipping... Markings for Fire and Emergency Equipment, Etc. § 97.37-9 Carbon dioxide alarm. (a) All carbon dioxide alarms shall be conspicuously identified: “WHEN ALARM SOUNDS—VACATE AT ONCE. CARBON DIOXIDE...

  2. 46 CFR 78.47-9 - Carbon dioxide alarm.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 3 2010-10-01 2010-10-01 false Carbon dioxide alarm. 78.47-9 Section 78.47-9 Shipping... and Emergency Equipment, Etc. § 78.47-9 Carbon dioxide alarm. (a) All carbon dioxide alarms shall be conspicuously identified: “WHEN ALARM SOUNDS—VACATE AT ONCE. CARBON DIOXIDE BEING RELEASED.” (b)...

  3. 46 CFR 196.37-9 - Carbon dioxide alarm.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 7 2010-10-01 2010-10-01 false Carbon dioxide alarm. 196.37-9 Section 196.37-9 Shipping... Markings for Fire and Emergency Equipment, etc. § 196.37-9 Carbon dioxide alarm. (a) All carbon dioxide alarms shall be conspicuously identified: “WHEN ALARM SOUNDS—VACATE AT ONCE. CARBON DIOXIDE...

  4. 46 CFR 108.627 - Carbon dioxide alarm.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 4 2010-10-01 2010-10-01 false Carbon dioxide alarm. 108.627 Section 108.627 Shipping... EQUIPMENT Equipment Markings and Instructions § 108.627 Carbon dioxide alarm. Each carbon dioxide alarm must be identified by marking: “WHEN ALARM SOUNDS VACATE AT ONCE. CARBON DIOXIDE BEING RELEASED” next...

  5. 46 CFR 95.15-20 - Carbon dioxide storage.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 4 2010-10-01 2010-10-01 false Carbon dioxide storage. 95.15-20 Section 95.15-20... PROTECTION EQUIPMENT Carbon Dioxide Extinguishing Systems, Details § 95.15-20 Carbon dioxide storage. (a... of not more than 300 pounds of carbon dioxide, may have the cylinders located within the...

  6. 46 CFR 76.15-20 - Carbon dioxide storage.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 3 2010-10-01 2010-10-01 false Carbon dioxide storage. 76.15-20 Section 76.15-20... EQUIPMENT Carbon Dioxide Extinguishing Systems, Details § 76.15-20 Carbon dioxide storage. (a) Except as... than 300 pounds of carbon dioxide, may have the cylinders located within the space protected. If...

  7. 46 CFR 169.732 - Carbon dioxide alarm.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 7 2010-10-01 2010-10-01 false Carbon dioxide alarm. 169.732 Section 169.732 Shipping... Control, Miscellaneous Systems, and Equipment Markings § 169.732 Carbon dioxide alarm. Each carbon dioxide alarm must be conspicuously identified: “WHEN ALARM SOUNDS—VACATE AT ONCE. CARBON DIOXIDE BEING RELEASED.”...

  8. Small diameter carbon nanopipettes

    Science.gov (United States)

    Singhal, Riju; Bhattacharyya, Sayan; Orynbayeva, Zulfiya; Vitol, Elina; Friedman, Gary; Gogotsi, Yury

    2010-01-01

    Nanoscale multifunctional carbon probes facilitate cellular studies due to their small size, which makes it possible to interrogate organelles within living cells in a minimally invasive fashion. However, connecting nanotubes to macroscopic devices and constructing an integrated system for the purpose of fluid and electrical signal transfer is challenging, as is often the case with nanoscale components. We describe a non-catalytic chemical vapor deposition based method for batch fabrication of integrated multifunctional carbon nanopipettes (CNPs) with tip diameters much smaller (10-30 nm) than previously reported (200 nm and above) and approaching those observed for multiwalled carbon nanotubes. This eliminates the need for complicated attachment/assembly of nanotubes into nanofluidic devices. Variable tip geometries and structures were obtained by controlled deposition of carbon inside and outside quartz pipettes. We have shown that the capillary length and gas flow rate have a marked effect on the carbon deposition. This gives us a flexible protocol, useful for growing carbon layers of different thicknesses at selective locations on a glass pipette to yield a large variety of cellular probes in bulk quantities. The CNPs possess an open channel for fluid transfer with the carbon deposited inside at 875 °C behaving like an amorphous semiconductor. Vacuum annealing of the CNP tips at temperatures up to 2000 °C yields graphitic carbon structures with an increase in conductivity of two orders of magnitude. Penetration of the integrated carbon nanoprobes into cells was shown to produce minimal Ca2+ signals, fast recovery of basal Ca2+ levels and no adverse activation of the cellular metabolism during interrogation times as long as 0.5-1 h.

  9. Small diameter carbon nanopipettes

    International Nuclear Information System (INIS)

    Nanoscale multifunctional carbon probes facilitate cellular studies due to their small size, which makes it possible to interrogate organelles within living cells in a minimally invasive fashion. However, connecting nanotubes to macroscopic devices and constructing an integrated system for the purpose of fluid and electrical signal transfer is challenging, as is often the case with nanoscale components. We describe a non-catalytic chemical vapor deposition based method for batch fabrication of integrated multifunctional carbon nanopipettes (CNPs) with tip diameters much smaller (10-30 nm) than previously reported (200 nm and above) and approaching those observed for multiwalled carbon nanotubes. This eliminates the need for complicated attachment/assembly of nanotubes into nanofluidic devices. Variable tip geometries and structures were obtained by controlled deposition of carbon inside and outside quartz pipettes. We have shown that the capillary length and gas flow rate have a marked effect on the carbon deposition. This gives us a flexible protocol, useful for growing carbon layers of different thicknesses at selective locations on a glass pipette to yield a large variety of cellular probes in bulk quantities. The CNPs possess an open channel for fluid transfer with the carbon deposited inside at 875 deg. C behaving like an amorphous semiconductor. Vacuum annealing of the CNP tips at temperatures up to 2000 deg. C yields graphitic carbon structures with an increase in conductivity of two orders of magnitude. Penetration of the integrated carbon nanoprobes into cells was shown to produce minimal Ca2+ signals, fast recovery of basal Ca2+ levels and no adverse activation of the cellular metabolism during interrogation times as long as 0.5-1 h.

  10. Carbon-carbon composites based on a polyimide matrix ITA

    Czech Academy of Sciences Publication Activity Database

    Yudin, V. E.; Goikhman, M. Y.; Gribanov, A. V.; Gubanova, G. N.; Kudryavtsev, V. V.; Balík, Karel; Glogar, Petr

    Singapore : World Scientific, 1996 - (Palmer, K.; Marx , D.; Wright, M.), s. 187-197 ISBN 981-02-2801-5. [Carbon and Carbonaceous Composite Materials: Structure-Property Relationships. Malenovice (CZ), 10.10.1995-13.10.1995] R&D Projects: GA ČR GA104/94/1789

  11. Pores and Cracks Analysis of Carbon-Carbon Composites

    Czech Academy of Sciences Publication Activity Database

    Weishauptová, Zuzana; Balík, Karel; Medek, Jiří

    Illinois : World Scientific Publishing Go.Pte.Ltd., 1996 - (Palmer, K.; Marx , D.; Wright, M.), s. 364-370 ISBN 981-02-2801-5. [International Conference on Carbon and Carbonaceous Composite Materials. Malenovice (CZ), 10.10.1995-13.10.1995] R&D Projects: GA ČR GA104/94/1789

  12. n型掺杂PTCDA复合材料对有机发光二极管性能的提高%Lithium Carbonate Doped 3,4,9,10-perylenetetracarboxylic Dianhydride for Enhanced Performance in Organic Light Emitting Diode

    Institute of Scientific and Technical Information of China (English)

    程翠然; 陈玉焕; 秦大山; 全威; 刘金锁

    2011-01-01

    采用碳酸锂(Li2CO3)为n型掺杂剂,苝四甲酸二酐(3,4,9,10 perylenetetracarboxylic dianhydride,PTCDA)为母体材料,通过真空热蒸发方式制备了n型掺杂的PTCDA复合材料,将其作为电子注入材料应用到NPB/Alq3异质结有机电致发光器件中.研究发现,同LI2CO3:BCP(1:4)/Al结构和LiF/Al结构相比,Li2CO3:PTCDA(1:1)/Al结构能显著提高发光器件的亮度,器件功率效率也有所增加.发光器件性能的提高可以归因于两点:一是Li2CO3:PTCDA(1:1)的电导率显著高于Li2CO3:BCP(1:4)和本征Alq3,能够有效降低电流传导过程中的欧姆损失;二是阴极Al原子的渗透使Alq3/Li2CO3:PTCDA界面变成欧姆接触.%Lithium carbonate doped 3,4,9,10-perylenetetracarboxylic dianhydride ( Li2CO3∶ PTCDA) was fabricated as electron injection layer in NPB/AIq3 heterojunction based organic light emitting diodes (OLEDs). It was found that the current of OLED using Li2CO3∶ PTCDA was strongly dependent on the Li2CO3 doping concentration. The OLED using Li2CO3∶ PTCDA( 1∶1 ) with A1 as the cathode exhibits an improved power etficiency and significantly increased luminance, comparing with the one using Li2CO3∶ BCP(1∶4) with Al as the cathode and the one using the regular LiF/Al cathode. It is because the electron conductivity for Li2CO3∶ PTCDA/( 1∶1 ) is much higher than that Li2CO3∶ BCP(1∶4) and neat Alq3. In addition, it is found that there exist a Schottky barrier at the intrinsic interface of Alq3 and Li2CO3∶ PTCDA( 1∶1 ), which suppress the electron transfer from Li2CO3∶ PTCDA( 1∶1 ) into Alq3. However, the release of Li atoms upon the Al deposition onto 1∶1 Li2CO3∶ PTCDA could turn the interface into an ohmic contact, thereby delivering efficient electron injection from Li2CO3∶ PTCDA( 1∶1 ) into Alq3. We provided a class of high-function, low-cost, and easily fabricated n-doped material for the performance enhancement of OLEDs.

  13. Conducting carbonized polyaniline nanotubes

    Czech Academy of Sciences Publication Activity Database

    Mentus, S.; Ciric-Marjanovic, G.; Trchová, Miroslava; Stejskal, Jaroslav

    2009-01-01

    Roč. 20, č. 24 (2009), 245601/1-245601/10. ISSN 0957-4484 R&D Projects: GA ČR GA203/08/0686; GA AV ČR IAA400500905 Institutional research plan: CEZ:AV0Z40500505 Keywords : conducting polymers * polyaniline * carbonization Subject RIV: CD - Macromolecular Chemistry Impact factor: 3.137, year: 2009

  14. Multimetallic Electrodeposition on Carbon Fibers

    Science.gov (United States)

    Böttger-Hiller, F.; Kleiber, J.; Böttger, T.; Lampke, T.

    2016-03-01

    Efficient lightweight design requires intelligent materials that meet versatile functions. One approach is to extend the range of properties of carbon fiber reinforced plastics (CFRP) by plating the fiber component. Electroplating leads to metalized layers on carbon fibers. Herein only cyanide-free electrolytes where used. Until now dendrite-free layers were only obtained using current densities below 1.0 A dm-2. In this work, dendrite-free tin and copper coatings were achieved by pre-metalizing the carbon fiber substrates. Furthermore, applying a combination of two metals with different sized thermal expansion coefficient lead to a bimetallic coating on carbon fiber rovings, which show an actuatory effect.

  15. Porous carbons

    Indian Academy of Sciences (India)

    Satish M Manocha

    2003-02-01

    Carbon in dense as well as porous solid form is used in a variety of applications. Activated porous carbons are made through pyrolysis and activation of carbonaceous natural as well as synthetic precursors. Pyrolysed woods replicate the structure of original wood but as such possess very low surface areas and poor adsorption capacities. On activation, these exhibit increased adsorption volumes of 0.5–0.8 cm3 /gm and surface areas of 700–1800 m2 /gm depending on activation conditions, whether physical or chemical. Former carbons possess mixed pore size distribution while chemically activated carbons predominantly possess micropores. Thus, these carbons can be used for adsorption of wide distributions of molecules from gas to liquid. The molecular adsorption within the pores is due to single layer or multilayer molecule deposition at the pore walls and hence results in different types of adsorption isotherm. On the other hand, activated carbon fibres with controlled microporous structure and surface area in the range of 2500 m2 /gm can be developed by controlled pyrolysis and physical activation of amorphous carbon fibres. Active carbon fibres with unmatchable pore structure and surface characteristics are present and futuristic porous materials for a number of applications from pollution control to energy storage.

  16. The research of a method for determination of total carbon, combination carbon and free carbon in beryllium metal

    International Nuclear Information System (INIS)

    A method for determination of total carbon, combination carbon and free carbon in beryllium metal with LECO CS-344 carbon/sulphur determinant has been studied. Tungsten-copper mixed pellets are used as flux to the determination of total carbon. Ratio of weight of the flux to the sample is greater than 20:1. Good analytical results are got. By this method the relative standard deviation is <10% when the content of total carbon in the range of 0.050%∼0.080% in beryllium. A standard steel sample of carbon is added into beryllium, the recoveries are 94%∼106%. For determination of free carbon, the sample are decomposed with 3 mol/L HCl, filtered and followed determination. By this method the relative standard deviation is ≤10% when the content of free carbon in the range of 0.006%∼0.020% in beryllium. the balance of total carbon and free carbon is equal to combination carbon. The method is used to determine the sample of content of total carbon in the range of 0.050%∼1.00%, free carbon in the range of 0.006%∼0.500% in metal beryllium. (6 refs., 1 fig., 13 tabs.)

  17. Fragmentation in Carbon Therapy Beams

    CERN Document Server

    Charara, Y M

    2010-01-01

    The state of the art Monte Carlo code HETC-HEDS was used to simulate spallation products, secondary neutron, and secondary proton production in A-150 Tissue Equivalent Plastic phantoms to investigate fragmentation of carbon therapy beams. For a 356 MeV/Nucleon carbon ion beam, production of charged particles heavier than protons was 0.24 spallation products per incident carbon ion with atomic numbers ranging from 1 through 5 (hydrogen to boron). In addition, there were 4.73 neutrons and 2.95 protons produced per incident carbon ion. Furthermore, as the incident energy increases, the neutron production rate increases at a rate of 20% per 10 MeV/nucleon. Secondary protons were created at a rate between 2.62-2.87 per carbon ion, while spallation products were created at a rate between 0.20-0.24 per carbon ion.

  18. Double-walled carbon nanotubes synthesized using carbon black as the dot carbon source

    Science.gov (United States)

    Chen, Zhi-Gang; Li, Feng; Ren, Wen-Cai; Cong, Hongtao; Liu, Chang; Qing Lu, Gao; Cheng, Hui-Ming

    2006-07-01

    Double-walled carbon nanotubes (DWNTs) were synthesized used carbon black as the dot carbon source by a semi-continuous hydrogen arc discharge process. High-resolution transmission electron microscopy (HRTEM) observations revealed that most of the tubes were DWNTs with outer and inner diameters in the range of 2.67-4 nm and 1.96-3.21 nm, respectively. Most of the DWNTs were in a bundle form of about 10-30 nm in diameter with high purity (about 70%) from thermal gravimetric analysis (TGA), resonant laser Raman spectroscopy, scanning electron microscopy (SEM) and TEM characterizations. It was found that carbon black as the dot carbon source could be easy controlled to synthesize one type of nanotube. A simple process combining oxidation and acid treatment to purify the DWNT bundles was used without damaging the bundles. The structure of carbon black, as the key element for influencing purity, bundle formation and purification of DWNTs, is discussed.

  19. Irradiation behavior of carbon-based composite materials

    International Nuclear Information System (INIS)

    Consideration is given to the data on radiation changes of sizes and some properties of different carbon-based composite materials (carbon-graphite and graphite-graphite compositions; carbon-carbon composite materials with carbon reinforcing fibers; carbon-silicon compositions), irradiated by neutrons at 320-1700 k. It is shown that change of sizes is dictated by the type and the ratio of components, forming (or not forming) the reinforcing uniform frame. 22 refs.; 10 figs

  20. Carbon and oxygen isotope microanalysis of carbonate.

    Science.gov (United States)

    Velivetskaya, Tatiana A; Ignatiev, Alexander V; Gorbarenko, Sergey A

    2009-08-30

    Technical modification of the conventional method for the delta(13)C and delta(18)O analysis of 10-30 microg carbonate samples is described. The CO(2) extraction is carried out in vacuum using 105% phosphoric acid at 95 degrees C, and the isotopic composition of CO(2) is measured in a helium flow by gas chromatography/isotope ratio mass spectrometry (GC/IRMS). The feed-motion of samples to the reaction vessel provides sequential dropping of only the samples (without the sample holder) into the acid, preventing the contamination of acid and allowing us to use the same acid to carry out very large numbers of analyses. The high accuracy and high reproducibility of the delta(13)C and delta(18)O analyses were demonstrated by measurements of international standards and comparison of results obtained by our method and by the conventional method. Our method allows us to analyze 10 microg of the carbonate with a standard deviation of +/-0.05 per thousand for delta(13)C and delta(18)O. The method has been used successfully for the analyses of the oxygen and carbon isotopic composition of the planktonic and benthic foraminifera in detailed palaeotemperature reconstructions of the Okhotsk Sea. PMID:19603476

  1. Calcium Carbonate

    Science.gov (United States)

    ... before being swallowed; do not swallow them whole. Drink a full glass of water after taking either the regular or chewable tablets or capsules. Some liquid forms of calcium carbonate must be shaken well before use.Do not ...

  2. Carbon Stars

    Indian Academy of Sciences (India)

    T. Lloyd Evans

    2010-12-01

    In this paper, the present state of knowledge of the carbon stars is discussed. Particular attention is given to issues of classification, evolution, variability, populations in our own and other galaxies, and circumstellar material.

  3. Carbon dioxide and climate

    International Nuclear Information System (INIS)

    Global climate change is a serious environmental concern, and the US has developed ''An Action Agenda'' to deal with it. At the heart of the US effort is the US Global Change Research Program (USGCRP), which has been developed by the Committee on Earth and Environmental Sciences (CEES) of the Federal Coordinating Council for Sciences, Engineering, and Technology (FCCSET). The USGCRP will provide the scientific basis for sound policy making on the climate-change issue. The DOE contribution to the USGCRP is the Carbon Dioxide Research Program, which now places particular emphasis on the rapid improvement of the capability to predict global and regional climate change. DOE's Carbon Dioxide Research Program has been addressing the carbon dioxide-climate change connection for more than twelve years and has provided a solid scientific foundation for the USGCRP. The expansion of the DOE effort reflects the increased attention that the Department has placed on the issue and is reflected in the National Energy Strategy (NES) that was released in 1991. This Program Summary describes projects funded by the Carbon Dioxide Research Program during FY 1991 and gives a brief overview of objectives, organization, and accomplishments. The Environmental Sciences Division of the Office of Health and Environmental Research, Office of Energy Research supports a Carbon Dioxide Research Program to determine the scientific linkage between the rise of greenhouse gases in the atmosphere, especially carbon dioxide, and climate and vegetation change. One facet is the Core CO2 Program, a pioneering program that DOE established more than 10 years ago to understand and predict the ways that fossil-fuel burning could affect atmospheric CO2 concentration, global climate, and the Earth's biosphere. Major research areas are: global carbon cycle; climate detection and models of climate change; vegetation research; resource analysis; and, information and integration

  4. Carbon dioxide gasification of carbon black: isotope study of carbonate catalysis

    International Nuclear Information System (INIS)

    Temperature-programmed reaction was used with labeled isotopes (13C and 18O) to study interactions between carbon black and potassium carbonate in pure He and 10% CO2/90% He atmospheres. Catalytic gasification precursor complexes were observed. Carbon and oxygen-bearing carbon surface groups interacted with the carbonate above 500 K to form surface complexes. Between 500 and 950 K, and in the presence of gaseous CO2, the complexes participated in C and O exchange with the gas phase while oxygen atoms within the complexes also exchanged with those on the carbon surface. As the temperature rose, the complexes decomposed, with CO2 the initial product. Decomposition started around 500 K in pure He, and around 950 K in CO2/He. Catalytic gasification began only after decomposition of significant portions of the complexes. Elemental potassium formed, and the active catalyst appears to alternate between being potassium metal and a potassium-oxygen-carbon complex. Potassium carbonate is not part of the catalytic cycle. 20 references, 10 figures

  5. Photo-degradation effect on dissolved organic carbon availability to bacterioplankton in a lake in the upper Paraná river floodplain - doi: 10.4025/actascibiolsci.v35i1.11054

    Directory of Open Access Journals (Sweden)

    Júlio César Rodrigues de Azevedo

    2012-12-01

    Full Text Available Dissolved organic carbon (DOC is nowadays recognized as the main substrate and source of energy for aquatic microbial community. The great part of available organic carbon for bacterioplankton might be formed after photolytic degradation of humic material, which constitutes the major part of DOC in almost all natural waters. The effects of DOC photo-degradation were evaluated, as was its utilization by bacterioplankton, through a two-step experiment, one involving photo-degradation of DOC and the other bacterial growth on the photo-degraded substrate. Photo-degradation was responsible for the consumption of 19% of DOC, reduced SUVA254, an increase in the E2/E3 and E3/E4 ratios, in addition to modifications in the fluorescence spectra that indicated a rise in the labile fraction of DOC. However, these alterations on DOC were not reflected in differences in bacterioplankton growth, as shown by the fact that there were no significant differences in density, biomass, bacterial production, bacterial respiration and bacterial growth efficiency between treatment and control.  

  6. Carbon particles

    Science.gov (United States)

    Hunt, Arlon J.

    1984-01-01

    A method and apparatus whereby small carbon particles are made by pyrolysis of a mixture of acetylene carried in argon. The mixture is injected through a nozzle into a heated tube. A small amount of air is added to the mixture. In order to prevent carbon build-up at the nozzle, the nozzle tip is externally cooled. The tube is also elongated sufficiently to assure efficient pyrolysis at the desired flow rates. A key feature of the method is that the acetylene and argon, for example, are premixed in a dilute ratio, and such mixture is injected while cool to minimize the agglomeration of the particles, which produces carbon particles with desired optical properties for use as a solar radiant heat absorber.

  7. Carbon nanotube network varactor

    International Nuclear Information System (INIS)

    Microelectromechanical system (MEMS) varactors based on a freestanding layer of single-walled carbon nanotube (SWCNT) films were designed, fabricated and tested. The freestanding SWCNT film was employed as a movable upper patch in the parallel plate capacitor of the MEMS. The measurements of the SWCNT varactors show very high tunability, nearly 100%, of the capacitance with a low actuation voltage of 10 V. The functionality of the varactor is improved by implementing a flexible nanocellulose aerogel filling. (paper)

  8. Carbon nanotube network varactor

    Science.gov (United States)

    Generalov, A. A.; Anoshkin, I. V.; Erdmanis, M.; Lioubtchenko, D. V.; Ovchinnikov, V.; Nasibulin, A. G.; Räisänen, A. V.

    2015-01-01

    Microelectromechanical system (MEMS) varactors based on a freestanding layer of single-walled carbon nanotube (SWCNT) films were designed, fabricated and tested. The freestanding SWCNT film was employed as a movable upper patch in the parallel plate capacitor of the MEMS. The measurements of the SWCNT varactors show very high tunability, nearly 100%, of the capacitance with a low actuation voltage of 10 V. The functionality of the varactor is improved by implementing a flexible nanocellulose aerogel filling.

  9. Carbon classified?

    DEFF Research Database (Denmark)

    Lippert, Ingmar

    2012-01-01

    . Using an actor- network theory (ANT) framework, the aim is to investigate the actors who bring together the elements needed to classify their carbon emission sources and unpack the heterogeneous relations drawn on. Based on an ethnographic study of corporate agents of ecological modernisation over a...... corporations construing themselves as able and suitable to manage their emissions, and, additionally, given that the construction of carbon emissions has performative consequences, the underlying practices need to be declassified, i.e. opened for public scrutiny. Hence the paper concludes by arguing for a...

  10. Dissolved inorganic carbon, temperature, salinity and other variables collected from discrete sample and profile observations using CTD, bottle and other instruments from the HUDSON in the North Atlantic Ocean from 1994-10-12 to 1994-11-10 (NODC Accession 0113555)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0113555 includes chemical, discrete sample, physical and profile data collected from HUDSON in the North Atlantic Ocean from 1994-10-12 to 1994-11-10...

  11. 液相氧化羰基化合成碳酸二乙酯的新型催化体系CuCl/1,10-菲罗啉/N-甲基咪唑%A Novel Catalyst CuCl/1,10-Phenanthroline/N-Methylimidazole for the Oxidative Carbonylation of Ethanol to Diethyl Carbonate

    Institute of Scientific and Technical Information of China (English)

    莫婉玲; 李光兴; 朱永强; 熊辉; 梅付名

    2003-01-01

    @@ Diethyl carbonate (DEC) is one of the important green chemicals widely used for organic synthesis because of its various functional groups. DEC is a better octane blending fuel, and has more oxygen in the molecule than methyl tert-butyl ether (MTBE), 40.6% versus 18.2%, which reduces emissions from gasoline and diesel engine. For these reasons many studies on the production of DEC have been extensively carried out.

  12. New generation of hybrid carbon/Ni(OH)2 electrochemical capacitor using functionalized carbon electrode

    Science.gov (United States)

    Le Comte, Annaïg; Brousse, Thierry; Bélanger, Daniel

    2016-09-01

    Tailoring carbon based negative electrode by grafting electroactive 9,10-phenanthrenequinone molecules on porous carbon drastically improves the performance of a carbon/Ni(OH)2 hybrid electrochemical capacitor. The grafted-quinone moieties add a Faradaic contribution to the double layer capacitance of carbon leading to a significant increase of the charge stored by the full devices. Good cyclability is ensured due to the strong bond between 9,10-phenanthrenequinone molecules and the carbon surface. More importantly, by increasing the total capacity, the grafting improves the energy density of the full hybrid device while maintaining fast charge/discharge kinetics and thus without affecting the power density.

  13. Physics-10

    Science.gov (United States)

    Marinciuc, Mihai; Rusu, Spiridon

    The textbook is designated for the 10-th class of real and humanitarian lyceums, according the curriculum of the Ministry of Education of the Republic of Moldova for lyceums. It encomprises mechanics in 5 chapters (Kynematics (Trajectory, Relativity of the Motion, Circular Motion and other); Dynamics and the Forces in Nature (The mass and Force, Universal attraction, Elastic Forces, Friction, The motion of the Bodies under the action of many forces, The relativity Principle of Galilei and other); Statics; Mechanical Impuls and its conservation; Mechanical work and Mechanical Energy and its conservation( Mechanical work and Power, Kynetic Energy, The mechanical work of the Elastic Force, The conservation laws) and Molecular Physics and Thermdynamics in 5 chapters (The structure of the Matter; Gases and their properties (Simplest transformations, The molecular-kynetic theory, Real gases) ; Solids and Liquids (The Hook's law, Superficial tension, Dilatation and other); Phase transitions (including sublimation); (Calorimetry; Thermal machines; The second law of thermodynamics and other). The textbook includes also 8 laboratory (experimental) works, a number of questions for control and a number of 300 problems, half of which have answers. Short biographies of about 15 physicists are included. The textbook is illustrated with diagrames, paintings and portrets in black and white.

  14. Photoluminescence enhancement of aligned arrays of single-walled carbon nanotubes by polymer transfer† †Electronic supplementary information (ESI) available. See DOI: 10.1039/c5nr05163k Click here for additional data file.

    Science.gov (United States)

    Schweiger, Manuel; Zakharko, Yuriy; Gannott, Florentina; Grimm, Stefan B.

    2015-01-01

    The photoluminescence of as-grown, aligned single-walled carbon nanotubes (SWNTs) on quartz is strongly quenched and barely detectable. Here we show that transferring these SWNTs to another substrate such as clean quartz or glass increases their emission efficiency by up to two orders of magnitude. By statistical analysis of large nanotube arrays we show at what point of the transfer process the emission enhancement occurs and how it depends on the receiving substrate and the employed transfer polymer. We find that hydrophobic polystyrene (PS) as the transfer polymer results in higher photoluminescence enhancement than the more hydrophilic poly(methyl methacrylate) (PMMA). Possible mechanisms for this enhancement such as strain relief, disruption of the strong interaction of SWNTs with the substrate and localized emissive states are discussed. PMID:26400227

  15. Three-Phase Carbon Fiber Amine Functionalized Carbon Nanotubes Epoxy Composite: Processing, Characterisation, and Multiscale Modeling

    OpenAIRE

    Kamal Sharma; Mukul Shukla

    2014-01-01

    The present paper discusses the key issues of carbon nanotube (CNT) dispersion and effect of functionalisation on the mechanical properties of multiscale carbon epoxy composites. In this study, CNTs were added in epoxy matrix and further reinforced with carbon fibres. Predetermined amounts of optimally amine functionalised CNTs were dispersed in epoxy matrix, and unidirectional carbon fiber laminates were produced. The effect of the presence of CNTs (1.0 wt%) in the resin was reflected by pro...

  16. 46 CFR 169.565 - Fixed carbon dioxide system.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 7 2010-10-01 2010-10-01 false Fixed carbon dioxide system. 169.565 Section 169.565... Lifesaving and Firefighting Equipment Firefighting Equipment § 169.565 Fixed carbon dioxide system. (a) The number of pounds of carbon dioxide required for each space protected must be equal to the gross volume...

  17. Carbon Dioxide, Hydrographic, and Chemical Data Obtained During the Nine R/V Korr Cruises Comprising the Indian Ocean CO2Survey (WOCE Sections I8SI9S, I9N, I8NI5E, I3, I5WI4, I7N, I1, I10, and I2; December 1, 1994-January 19, 1996)

    Energy Technology Data Exchange (ETDEWEB)

    Kozyr, A.V.

    2003-09-15

    This document describes the procedures and methods used to measure total carbon dioxide (TCO{sub 2}) and total alkalinity (TALK) at hydrographic stations taken during the R/V Knorr Indian Ocean cruises (Sections I8SI9S, I9N, I8NI5E, I3, I5WI4, I7N, I1, I10, and I2) in 1994-1996. The measurements were conducted as part of the World Ocean Circulation Experiment (WOCE). The expedition began in Fremantle, Australia, on December 1, 1994, and ended in Mombasa, Kenya, on January 22, 1996. During the nine cruises, 12 WOCE sections were occupied. Total carbon dioxide was extracted from water samples and measured using single-operator multiparameter metabolic analyzers (SOMMAs) coupled to coulometers. The overall precision and accuracy of the analyses was {+-} 1.20 {micro}mol/kg. The second carbonate system parameter, TALK, was determined by potentiometric titration. The precision of the measurements determined from 962 analyses of certified reference material was {+-} 4.2 {micro}mol/kg (REFERENCE). This work was supported by grants from the National Science Foundation, the U. S. Department of Energy, and the National Oceanographic and Atmospheric Administration. The R/V Knorr Indian Ocean data set is available as a numeric data package (NDP) from the Carbon Dioxide Information Analysis Center (CDIAC). The NDP consists of 18 oceanographic data files, two FORTRAN 77 data retrieval routine files, a readme file, and this printed documentation, which describes the contents and format of all files as well as the procedures and methods used to obtain the data. Instructions for accessing the data are provided.

  18. Enhancement of enterotoxin production by carbon dioxide in Vibrio cholerae.

    OpenAIRE

    Shimamura, T; Watanabe, S; Sasaki, S.

    1985-01-01

    We found that Vibrio cholerae 569B produced much more cholera enterotoxin in the presence of added carbon dioxide than in its absence. An atmosphere of 10% carbon dioxide was optimal for maximal enterotoxin production.

  19. A transport modeling of the carbon-nitrogen cycle at Igapó I Lake - Londrina, Paraná State, Brazil - doi: 10.4025/actascitechnol.v34i2.11792

    Directory of Open Access Journals (Sweden)

    Suellen Ribeiro Pardo

    2012-03-01

    Full Text Available This work is a contribution to a better understanding of the effect that domestic sewage discharges may cause in a water body, specifically at Igapó I Lake, in Londrina, Paraná State, Brazil. The simulation of the dynamics of pollutant concentrations throughout the water body was conducted by means of structured discretization of the geometry of Igapó I Lake, together with the finite differences and the finite elements methods. Firstly, the hydrodynamic flow (without the pollutants, modeled by Navier-Stokes and pressure equations, was numerically resolved by the finite differences method, and associated with the fourth order Runge-Kutta procedure. After that, by using the hydrodynamic field velocity, the flow of the reactive species (pollutants was described through a reaction transport model, restricted to the carbon-nitrogen cycle. The reaction transport model was numerically resolved by the stabilized finite elements method, by means of a semi-discrete formulation. A qualitative analysis of the numerical simulations provided a better understanding of the dynamics of the processes involved in the flow of the reactive species, such as the dynamics of the nitrification process, of the biochemical demand of oxygen and of the level of oxygen dissolved in the water body at Igapó I Lake.

  20. Blue carbon stocks in Baltic Sea eelgrass (Zostera marina) meadows

    OpenAIRE

    Röhr, Maria Emilia; Boström, Christoffer; Canal-Vergés, Paula; Holmer, Marianne

    2016-01-01

    Although seagrasses cover only a minor fraction of the ocean seafloor, their carbon sink capacity account for nearly one-fifth of the oceanic carbon burial and thus play a critical structural and functional role in many coastal ecosystems. We sampled 10 eelgrass (Zostera marina) meadows in Finland and 10 in Denmark to explore the seagrass carbon stocks (Corg stock) and the carbon accumulation (Corg accumulation) in the Baltic Sea area. The study sites represent a gradient from sheltered to ex...

  1. From Carbon Nanotube Crystals to Carbon Nanotube Flowers

    Institute of Scientific and Technical Information of China (English)

    ZHANG Zhengjun; ZHAO Ye; ZHOU Ya

    2005-01-01

    We have investigated the very initial deposition stages of chemical vapor deposition (CVD) with ferrocene (Fe(C5H5)2) and xylene (C8H10) for growing carbon nanotubes, and made clear that the mechanism for the self-organization behaviors of nanotubes at different growth stages by this approach. For instance, the organization of nanotubes into flower-like structures at prolonged deposition is developed from the crystal-like structures formed at early growth stages, both of which are closely related to and determined by the very initial deposition stages of this CVD approach. Based on this approach, ways have been established to build up different architectures of carbon nanotubes, by controlling the initial deposition stages of the CVD process, with which we have realized the selective growth of self-organized carbon nanotube structures. This study provides a new idea for growing carbon nanotube architectures by CVD.

  2. Carbon films produced from ionic liquid carbon precursors

    Science.gov (United States)

    Dai, Sheng; Luo, Huimin; Lee, Je Seung

    2013-11-05

    The invention is directed to a method for producing a film of porous carbon, the method comprising carbonizing a film of an ionic liquid, wherein the ionic liquid has the general formula (X.sup.+a).sub.x(Y.sup.-b).sub.y, wherein the variables a and b are, independently, non-zero integers, and the subscript variables x and y are, independently, non-zero integers, such that ax=by, and at least one of X.sup.+ and Y.sup.- possesses at least one carbon-nitrogen unsaturated bond. The invention is also directed to a composition comprising a porous carbon film possessing a nitrogen content of at least 10 atom %.

  3. Carbon neutron star atmospheres

    CERN Document Server

    Suleimanov, V F; Pavlov, G G; Werner, K

    2013-01-01

    The accuracy of measuring the basic parameters of neutron stars is limited in particular by uncertainties in chemical composition of their atmospheres. For example, atmospheres of thermally - emitting neutron stars in supernova remnants might have exotic chemical compositions, and for one of them, the neutron star in CasA, a pure carbon atmosphere has recently been suggested by Ho & Heinke (2009). To test such a composition for other similar sources, a publicly available detailed grid of carbon model atmosphere spectra is needed. We have computed such a grid using the standard LTE approximation and assuming that the magnetic field does not exceed 10^8 G. The opacities and pressure ionization effects are calculated using the Opacity Project approach. We describe the properties of our models and investigate the impact of the adopted assumptions and approximations on the emergent spectra.

  4. Carbon speciation and surface tension of fog

    Science.gov (United States)

    Capel, P.D.; Gunde, R.; Zurcher, F.; Giger, W.

    1990-01-01

    The speciation of carbon (dissolved/particulate, organic/inorganic) and surface tension of a number of radiation fogs from the urban area of Zurich, Switzerland, were measured. The carbon species were dominated by "dissolved" organic carbon (DOC; i.e., the fraction that passes through a filter), which was typically present at levels of 40-200 mg/L. Less than 10% of the DOC was identified as specific individual organic compounds. Particulate organic carbon (POC) accounted for 26-41% of the mass of the particles, but usually less than 10% of the total organic carbon mass. Inorganic carbon species were relatively minor. The surface tensions of all the measured samples were less than pure water and were correlated with their DOC concentrations. The combination of high DOC and POC and low surface tension suggests a mechanism for the concentration of hydrophobic organic contaminants in the fog droplet, which have been observed by numerous investigators. ?? 1990 American Chemical Society.

  5. CarbonSat Constellation

    Science.gov (United States)

    Sun, Wei; Tobehn, Carsten; Ernst, Robert; Bovensmann, Heinrich; Buchwitz, Michael; Burrows, John P.; Notholt, John

    1 Carbon dioxide (CO2) and methane (CH4) are the most important manmade greenhouse gases (GHGs) which are driving global climate change. Currently, the CO2 measurements from the ground observing network are still the main sources of information but due to the limited number of measurement stations the coverage is limited. In addition, CO2 monitoring and trading is often based mainly on bottom-up calculations and an independent top down verification is limited due to the lack of global measurement data with local resolution. The first CO2 and CH4 mapping from SCIAMACHY on ENVISAT shows that satellites add important missing global information. Current GHG measurement satellites (GOSAT)are limited either in spatial or temporal resolution and coverage. These systems have to collect data over a year or even longer to produce global regional fluxes products. Conse-quently global, timely, higher spatial resolution and high accuracy measurement are required for: 1. A good understanding of the CO2 and CH4 sources and sinks for reliable climate predic-tion; and 2. Independent and transparent verification of accountable sources and sinks in supporting Kyoto and upcoming protocols The CarbonSat constellation idea comes out the trade off of resolution and swath width during CarbonSat mission definition studies. In response to the urgent need to support the Kyoto and upcoming protocols, a feasibility study has been carried out. The proposed solution is a constellation of five CarbonSat satellites in 614km LTAN 13:00, which is able to provide global, daily CO2 and CH4 measurement everywhere on the Earth with high spatial resolution 2 × 2 km and low uncertainty lt;2ppm (CO2) and lt;8ppb (CH4). The unique global daily measurement capability significantly increases the number of cloud free measurements, which enables more reliable services associated with reduced uncertainty, e.g. to 0.15ppm (CO2) per month in 10km and even more timely products. The CarbonSat Constellation in

  6. Contribution to analysis of fatigue crack propagation at room temperature in low carbon austenitic steels type 18-10(304L) and Mo 17-12(316L). Relation between macroscopic and microscopic phenomena

    International Nuclear Information System (INIS)

    Low cycle fatigue phenomenon on the structural components of reactors is one of the most important problem. In this paper were carried out some fatigue tests on stainless steels type Z2CN18-10 (AISI 304L) and Z2CND17-12 (AISI 316L) at room temperature in air and in a corrosive medium (NaCl solution at different pH values). Length of cracks and crack propagation under stresses were determined. Z2CND17-12 has a better behavior than Z2CN18-10 because of a better structural stability both in air and in a corrosive environment. Structure was examined by transmission electron microscopy and microhardness was measured in the perturbed zones

  7. δ18O water isotope in the iLOVECLIM model (version 1.0 – Part 3: A paleoperspective based on present-day data-model comparison for oxygen stable isotopes in carbonates

    Directory of Open Access Journals (Sweden)

    T. Caley

    2013-03-01

    Full Text Available Oxygen stable isotopes (18O are among the most usual tools in paleoclimatology/paleoceanography. Simulation of oxygen stable isotopes allows testing how the past variability of these isotopes in water can be interpreted. By modelling the proxy directly in the model, the results can also be directly compared with the data. Water isotopes have been implemented in the global three-dimensional model of intermediate complexity iLOVECLIM allowing fully coupled atmosphere-ocean simulations. In this study, we present the validation of the model results for present day climate against global database for oxygen stable isotopes in carbonates. The limitation of the model together with the processes operating in the natural environment reveal the complexity of use the continental calcite 18O signal of speleothems for a data-model comparison exercise. On the contrary, the reconstructed surface ocean calcite δ18O signal in iLOVECLIM does show a very good agreement with late Holocene database (foraminifers at the global and regional scales. Our results indicate that temperature and the isotopic composition of the seawater are the main control on the fossil δ18O signal recorded in foraminifer shells and that depth habitat and seasonality play a role but have secondary importance. We argue that a data-model comparison for surface ocean calcite δ18O in past climate, such as the last glacial maximum (≈21 000 yr, could constitute an interesting tool for mapping the potential shifts of the frontal systems and circulation changes throughout time. Similarly, the potential changes in intermediate oceanic circulation systems in the past could be documented by a data (benthic foraminifers-model comparison exercise whereas future investigations are necessary in order to quantitatively compare the results with data for the deep ocean.

  8. δ18O water isotope in the iLOVECLIM model (version 1.0 – Part 3: A palaeo-perspective based on present-day data–model comparison for oxygen stable isotopes in carbonates

    Directory of Open Access Journals (Sweden)

    T. Caley

    2013-09-01

    Full Text Available Oxygen stable isotopes (δ18O are among the most useful tools in palaeoclimatology/palaeoceanography. Simulation of oxygen stable isotopes allows testing how the past variability of these isotopes in water can be interpreted. By modelling the proxy directly in the model, the results can also be directly compared with the data. Water isotopes have been implemented in the global three-dimensional model of intermediate complexity iLOVECLIM, allowing fully coupled atmosphere–ocean simulations. In this study, we present the validation of the model results for present-day climate against the global database for oxygen stable isotopes in carbonates. The limitation of the model together with the processes operating in the natural environment reveal the complexity of use the continental calcite-δ18O signal of speleothems for a global quantitative data–model comparison exercise. On the contrary, the reconstructed surface ocean calcite-δ18O signal in iLOVECLIM does show a very good agreement with the late Holocene database (foraminifers at the global and regional scales. Our results indicate that temperature and the isotopic composition of the seawater are the main control on the fossil-δ18O signal recorded in foraminifer shells when all species are grouped together. Depth habitat, seasonality and other ecological effects play a more significant role when individual species are considered. We argue that a data–model comparison for surface ocean calcite δ18O in past climates, such as the Last Glacial Maximum (≈ 21 000 yr, could constitute an interesting tool for mapping the potential shifts of the frontal systems and circulation changes throughout time. Similarly, the potential changes in intermediate oceanic circulation systems in the past could be documented by a data (benthic foraminifers-model comparison exercise whereas future investigations are necessary in order to quantitatively compare the results with data for the deep ocean.

  9. T2Well/ECO2N Version 1.0: Multiphase and Non-Isothermal Model for Coupled Wellbore-Reservoir Flow of Carbon Dioxide and Variable Salinity Water

    Energy Technology Data Exchange (ETDEWEB)

    Pan, L.; Oldenburg, C.M.; Wu, Y.-S.; Pruess, K.

    2011-02-14

    At its most basic level, the injection of CO{sub 2} into geologic CO{sub 2} storage sites involves a system comprising the wellbore and the target reservoir. The wellbore is the only conduit available to emplace CO{sub 2} into reservoirs for long-term storage. At the same time, wellbores in general have been identified as the most likely conduit for CO{sub 2} and brine leakage from geologic carbon sequestration (GCS) sites, especially those in sedimentary basins with historical hydrocarbon production. We have developed a coupled wellbore and reservoir model for simulating the dynamics of CO{sub 2} injection and leakage through wellbores. The model describes the following processes: (1) upward or downward wellbore flow of CO{sub 2} and variable salinity water with transition from supercritical to gaseous CO{sub 2} including Joule-Thomson cooling, (2) exsolution of CO{sub 2} from the aqueous phase as pressure drops, and (3) cross flow into or interaction with layers of surrounding rock (reservoirs). We use the Drift-Flux Model and related conservation equations for describing transient two-phase non-isothermal wellbore flow of CO{sub 2}-water mixtures under different flow regimes and interacting with surrounding rock. The mass and thermal energy balance equations are solved numerically by a finite difference scheme with wellbore heat transmission to the surrounding rock handled either semi-analytically or numerically. The momentum balance equation for the flow in the wellbore is solved numerically with a semi-explicit scheme. This manual provides instructions for compilation and use of the new model, and presents some example problems to demonstrate its use.

  10. Imobilização da pancreatina em carvão ativado e em alumina para o preparo de hidrolisados de soro de leite - DOI: 10.4025/actascihealthsci.v27i2.1417 Immobilization of pancreatin in activated carbon and in alumina for preparing whey hydrolysates - DOI: 10.4025/actascihealthsci.v27i2.1417

    Directory of Open Access Journals (Sweden)

    Marialice Pinto Coelho Silvestre

    2005-03-01

    Full Text Available Tendo como objetivo a redução de custos do processo de fabricação de hidrolisados protéicos, estudou-se neste trabalho a imobilização da pancreatina, por adsorção, em carvão ativado e em alumina. Para isso, foram testadas diferentes condições de imobilização (30, 60 e 90min a 25°C, e 12h a 5°C. Para verificar a taxa de imobilização, determinou-se indiretamente a enzima não adsorvida nos suportes. Ao se utilizar o carvão ativado, não foi observada diferença significativa entre as condições testadas, tendo-se obtido 100% de imobilização enzimática. Para a alumina, a melhor condição foi a de 90min, na qual se obteve 37% de imobilização. A medida do grau de exposição da fenilalanina, pela espectrofotometria derivada segunda, foi empregada para a determinação da estabilidade operacional da enzima, tendo sido mostrado que a imobilização em carvão ativado e em alumina permitiu a reutilização da pancreatina por até 5 vezes e 2 vezes, respectivamenteImmobilization of pancreatin in activated carbon and in alumina was studied for producing protein hydrolysates, in order to reduce the process costs. Different immobilization conditions were tested (30, 60 and 90min at 25°C, and 12h at 5°C. For estimating the immobilization rate the amount of the non-adsorbed enzyme on the supports was indirectly determined. When activated carbon was used, no significant difference was observed among the tested conditions, obtaining 100% of enzymatic immobilization. In case of alumina, the best condition showed to be the 90min treatment which produced 37% of immobilization. The evaluation of the degree of exposition of phenylalanine, by second derivative spectrophotometry, was used for the determination of the enzyme operational stability, and showed that the immobilization in activated carbon and in alumina allowed the reusability of the pancreatin for 5 times and 2 times, respectively

  11. Ocean uptake of carbon dioxide

    International Nuclear Information System (INIS)

    Factors controlling the capacity of the ocean for taking up anthropogenic C02 include carbon chemistry, distribution of alkalinity, pCO2 and total concentration of dissolved C02, sea-air pCO2 difference, gas exchange rate across the sea-air interface, biological carbon pump, ocean water circulation and mixing, and dissolution of carbonate in deep sea sediments. A general review of these processes is given and models of ocean-atmosphere system based on our understanding of these regulating processes axe used to estimate the magnitude of C02 uptake by the ocean. We conclude that the ocean can absorb up to 35% of the fossil fuel emission. Direct measurements show that 55% Of C02 from fossil fuel burning remains in the atmosphere. The remaining 10% is not accounted for by atmospheric increases and ocean uptake. In addition, it is estimated that an amount equivalent to 30% of recent annual fossil fuel emissions is released into the atmosphere as a result of deforestation and farming. To balance global carbon budget, a sizable carbon sink besides the ocean is needed. Storage of carbon in terrestrial biosphere as a result of C02 fertilization is a potential candidate for such missing carbon sinks

  12. Spherical carbons: Synthesis, characterization and activation processes

    OpenAIRE

    Romero Anaya, Aroldo José; Ouzzine, Mohammed; Lillo Ródenas, María Ángeles; Linares Solano, Ángel

    2014-01-01

    Spherical carbons have been prepared through hydrothermal treatment of three carbohydrates (glucose, saccharose and cellulose). Preparation variables such as treatment time, treatment temperature and concentration of carbohydrate have been analyzed to obtain spherical carbons. These spherical carbons can be prepared with particle sizes larger than 10 μm, especially from saccharose, and have subsequently been activated using different activation processes (H3PO4, NaOH, KOH or physical activati...

  13. Dissolved inorganic carbon, pH, alkalinity, temperature, salinity and other variables collected from discrete sample and profile observations using CTD, Coulometer for DIC measurement and other instruments from the BOSEI MARU NO. 2 in the North Pacific Ocean from 1999-10-07 to 1999-10-26 (NODC Accession 0112199)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0112199 includes chemical, discrete sample, physical and profile data collected from BOSEI MARU NO. 2 in the North Pacific Ocean from 1999-10-07 to...

  14. Dissolved inorganic carbon, pH, alkalinity, temperature, salinity and other variables collected from discrete sample and profile observations using CTD, Coulometer for DIC measurement and other instruments from the BOSEI MARU NO. 2 in the North Pacific Ocean from 1998-10-03 to 1998-10-20 (NODC Accession 0112190)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0112190 includes chemical, discrete sample, physical and profile data collected from BOSEI MARU NO. 2 in the North Pacific Ocean from 1998-10-03 to...

  15. Dissolved inorganic carbon, pH, alkalinity, temperature, salinity and other variables collected from discrete sample and profile observations using CTD, Coulometer for DIC measurement and other instruments from the BOSEI MARU NO. 2 in the North Pacific Ocean from 2000-10-06 to 2000-10-21 (NODC Accession 0112200)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0112200 includes chemical, discrete sample, physical and profile data collected from BOSEI MARU NO. 2 in the North Pacific Ocean from 2000-10-06 to...

  16. Dissolved inorganic carbon, alkalinity, temperature, salinity and other variables collected from discrete sample and profile observations using CTD, bottle and other instruments from the THOMAS WASHINGTON in the South Atlantic Ocean from 1984-10-01 to 1984-10-22 (NODC Accession 0117693)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0117693 includes chemical, discrete sample, physical and profile data collected from THOMAS WASHINGTON in the South Atlantic Ocean from 1984-10-01 to...

  17. Dissolved inorganic carbon, pH, alkalinity, temperature, salinity and other variables collected from discrete sample and profile observations using CTD, Coulometer for DIC measurement and other instruments from the SHUMPU MARU in the Philippine Sea from 1998-10-07 to 1998-10-15 (NODC Accession 0112305)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0112305 includes biological, chemical, discrete sample, physical and profile data collected from SHUMPU MARU in the Philippine Sea from 1998-10-07 to...

  18. Dissolved inorganic carbon, pH, alkalinity, temperature, salinity and other variables collected from discrete sample and profile observations using CTD, Coulometer for DIC measurement and other instruments from the SHUMPU MARU in the Philippine Sea from 1999-10-06 to 1999-10-14 (NODC Accession 0112310)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0112310 includes biological, chemical, discrete sample, physical and profile data collected from SHUMPU MARU in the Philippine Sea from 1999-10-06 to...

  19. Carbon Segregation of Bearing Steel Concasting Billet

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    The formation mechanism of “white band” and central carbon segregation of high-carbon Cr bearing steel concasting billets are discussed in this paper. The maximum oxygen content in the steel produced by concasting process was 13x10-6 with an average oxygen content of 9.3x 10-6.Comparison of metallurgical quality and fatigue property between the concasting steel (CC) andingot casting steel (IC) showed that the carbon segregation (C/C0) in former steel was 0.92~1.10and its fatigue life was equal to that of the latter steel.

  20. Carbon allowance allocation in the transportation industry

    International Nuclear Information System (INIS)

    This study proposes models for projecting reductions in CO2 emissions of 10%, 20%, 30%, and 40% compared to business as usual (BAU), using a carbon allowance allocation policy and both unimodal and intermodal modes of transportation. The results show that for 10% to 80% decreases in free carbon allowance, the intermodal ratio increased from 1.01% to 53.44%, which led to decreases in carbon emissions and demand ranging from 10.41% to 48.19% and 8.45% to 7.57%, respectively. When free carbon allowances are decreased, the demand for intermodal systems increases accordingly. These results suggest that a carbon allowance allocation policy could mitigate transportation carbon emissions with a relatively small negative impact on economic activity. - Highlights: • This study proposes models for CO2 reduction by using carbon allowance policy. • This study found decreases in carbon allowance allocation, the intermodal ratio increased. • Truck-only transport will be replaced by intermodal transport. • The carbon allowance allocation policy cause small negative impact on economic activity

  1. Carbon Footprints

    OpenAIRE

    Rahel Aichele; Gabriel Felbermayr

    2011-01-01

    Lässt sich der Beitrag eines Landes zum weltweiten Klimaschutz an der Veränderung seines CO2-Ausstoßes messen, wie es im Kyoto-Abkommen implizit unterstellt wird? Oder ist aufgrund der Bedeutung des internationalen Güterhandels der Carbon Footprint – der alle CO2-Emissionen erfasst, die durch die Absorption (d.h. Konsum und Investitionen) eines Landes entstehen – das bessere Maß? Die Autoren erstellen eine Datenbank mit den Footprints von 40 Ländern für den Zeitraum 1995–2007. Die deskriptive...

  2. TYPE Ia SUPERNOVA CARBON FOOTPRINTS

    International Nuclear Information System (INIS)

    We present convincing evidence of unburned carbon at photospheric velocities in new observations of five Type Ia supernovae (SNe Ia) obtained by the Nearby Supernova Factory. These SNe are identified by examining 346 spectra from 124 SNe obtained before +2.5 days relative to maximum. Detections are based on the presence of relatively strong C II λ6580 absorption 'notches' in multiple spectra of each SN, aided by automated fitting with the SYNAPPS code. Four of the five SNe in question are otherwise spectroscopically unremarkable, with ions and ejection velocities typical of SNe Ia, but spectra of the fifth exhibit high-velocity (v > 20, 000 km s–1) Si II and Ca II features. On the other hand, the light curve properties are preferentially grouped, strongly suggesting a connection between carbon-positivity and broadband light curve/color behavior: three of the five have relatively narrow light curves but also blue colors and a fourth may be a dust-reddened member of this family. Accounting for signal to noise and phase, we estimate that 22+10–6% of SNe Ia exhibit spectroscopic C II signatures as late as –5 days with respect to maximum. We place these new objects in the context of previously recognized carbon-positive SNe Ia and consider reasonable scenarios seeking to explain a physical connection between light curve properties and the presence of photospheric carbon. We also examine the detailed evolution of the detected carbon signatures and the surrounding wavelength regions to shed light on the distribution of carbon in the ejecta. Our ability to reconstruct the C II λ6580 feature in detail under the assumption of purely spherical symmetry casts doubt on a 'carbon blobs' hypothesis, but does not rule out all asymmetric models. A low volume filling factor for carbon, combined with line-of-sight effects, seems unlikely to explain the scarcity of detected carbon in SNe Ia by itself.

  3. Carbon Nanomembranes.

    Science.gov (United States)

    Turchanin, Andrey; Gölzhäuser, Armin

    2016-08-01

    Carbon nanomembranes (CNMs) are synthetic 2D carbon sheets with tailored physical or chemical properties. These depend on the structure, molecular composition, and surroundings on either side. Due to their molecular thickness, they can be regarded as "interfaces without bulk" separating regions of different gaseous, liquid, or solid components and controlling the materials exchange between them. Here, a universal scheme for the fabrication of 1 nm-thick, mechanically stable, functional CNMs is presented. CNMs can be further modified, for example perforated by ion bombardment or chemically functionalized by the binding of other molecules onto the surfaces. The underlying physical and chemical mechanisms are described, and examples are presented for the engineering of complex surface architectures, e.g., nanopatterns of proteins, fluorescent dyes, or polymer brushes. A simple transfer procedure allows CNMs to be placed on various support structures, which makes them available for diverse applications: supports for electron and X-ray microscopy, nanolithography, nanosieves, Janus nanomembranes, polymer carpets, complex layered structures, functionalization of graphene, novel nanoelectronic and nanomechanical devices. To close, the potential of CNMs in filtration and sensorics is discussed. Based on tests for the separation of gas molecules, it is argued that ballistic membranes may play a prominent role in future efforts of materials separation. PMID:27281234

  4. Carbon thin film thermometry

    Science.gov (United States)

    Collier, R. S.; Sparks, L. L.; Strobridge, T. R.

    1973-01-01

    The work concerning carbon thin film thermometry is reported. Optimum film deposition parameters were sought on an empirical basis for maximum stability of the films. One hundred films were fabricated for use at the Marshall Space Flight Center; 10 of these films were given a precise quasi-continuous calibration of temperature vs. resistance with 22 intervals between 5 and 80 K using primary platinum and germanium thermometers. Sensitivity curves were established and the remaining 90 films were given a three point calibration and fitted to the established sensitivity curves. Hydrogen gas-liquid discrimination set points are given for each film.

  5. Trading forest carbon

    Science.gov (United States)

    The nature of carbon in forests is discussed from the perspective of carbon trading. Carbon inventories, specifically in the area of land use and forestry are reviewed for the Pacific Northwest. Carbon turnover in forests is discussed as it relates to carbon sequestration. Scient...

  6. Putting a Price On Carbon

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    The Australian Government unveils its new climate change plan amid controversy The Australian Government made public its long awaited new climate change plan on July 10. Based on the plan,the government will collect a carbon tax from Australia’s major

  7. Controls on the Time Scale of Carbonate Neutralization of Carbon Dioxide Released to the Atmosphere

    Science.gov (United States)

    Caldeira, K.; Cao, L.

    2007-12-01

    Once released to the atmosphere, carbon dioxide is removed on a range of time scales. On the time scale of years to centuries, carbon dioxide removal from the atmosphere is dominated by transport processes within the ocean. On the time scale of hundreds of thousands of years, carbon dioxide removal from the atmosphere is dominated by processes related to the weathering of silicate rocks on land. Between these time scales, carbon dioxide removal is dominated by interactions involving carbonate minerals both on land and in the sea. Net dissolution of carbonate minerals (on land or in the sea) increases ocean alkalinity to an extent that exceeds the amount of carbon addition; the result is a transfer of carbon from the atmosphere to the ocean and moderation of the effects of added carbon on ocean chemical parameters such as pH and carbonate mineral saturation. There has been some controversy over how fast equilibration with carbonate minerals can neutralize carbon acidity, with claims ranging from the extreme and untenable claim that this process is essentially instantaneous to more plausible claims that the equilibration time scale may approach 10 kyr. Even within the domain of informed discourse, estimates of the carbonate neutralization timescale can vary by an order-of-magnitude. Here, in an effort to understand the sources of the lack of consensus on this issue, we examine how various processes (e.g., ocean transport, sediment pore water diffusion, carbonate-mineral dissolution, and carbonate weathering on land) influence the time scale for carbonate neutralization of carbon dioxide releases to the atmosphere.

  8. Partial pressure (or fugacity) of carbon dioxide, dissolved inorganic carbon, pH, alkalinity, temperature, salinity and other variables collected from discrete sample and profile observations using Alkalinity titrator, CTD and other instruments from the KNORR in the South Pacific Ocean from 2005-08-21 to 2005-10-06 (NODC Accession 0108071)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0108071 includes chemical, discrete sample, physical and profile data collected from KNORR in the South Pacific Ocean from 2005-08-21 to 2005-10-06...

  9. Partial pressure (or fugacity) of carbon dioxide, dissolved inorganic carbon, alkalinity, temperature, salinity and other variables collected from discrete sample and profile observations using CTD, bottle and other instruments from the METEOR in the South Atlantic Ocean from 1991-02-10 to 1991-03-23 (NODC Accession 0115022)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0115022 includes chemical, discrete sample, physical and profile data collected from METEOR in the South Atlantic Ocean from 1991-02-10 to 1991-03-23...

  10. Influence of variable rates of neritic carbonate deposition on atmospheric carbon dioxide and pelagic sediments

    Science.gov (United States)

    Walker, J. C.; Opdyke, B. C.

    1995-01-01

    Short-term imbalances in the global cycle of shallow water calcium carbonate deposition and dissolution may be responsible for much of the observed Pleistocene change in atmospheric carbon dioxide content. However, any proposed changes in the alkalinity balance of the ocean must be reconciled with the sedimentary record of deep-sea carbonates. The possible magnitude of the effect of shallow water carbonate deposition on the dissolution of pelagic carbonate can be tested using numerical simulations of the global carbon cycle. Boundary conditions can be defined by using extant shallow water carbonate accumulation data and pelagic carbonate deposition/dissolution data. On timescales of thousands of years carbonate deposition versus dissolution is rarely out of equilibrium by more than 1.5 x 10(13) mole yr-1. Results indicate that the carbonate chemistry of the ocean is rarely at equilibrium on timescales less than 10 ka. This disequilibrium is probably due to sea level-induced changes in shallow water calcium carbonate deposition/dissolution, an interpretation that does not conflict with pelagic sedimentary data from the central Pacific.

  11. Global deforestation: contribution to atmospheric carbon dioxide.

    Science.gov (United States)

    Woodwell, G M; Hobbie, J E; Houghton, R A; Melillo, J M; Moore, B; Peterson, B J; Shaver, G R

    1983-12-01

    A study of effects of terrestrial biota on the amount of carbon dioxide in the atmosphere suggests that the global net release of carbon due to forest clearing between 1860 and 1980 was between 135 x 10(15) and 228 x 10(15) grams. Between 1.8 x 10(15) and 4.7 x 10(15) grams of carbon were released in 1980, of which nearly 80 percent was due to deforestation, principally in the tropics. The annual release of carbon from the biota and soils exceeded the release from fossil fuels until about 1960. Because the biotic release has been and remains much larger than is commonly assumed, the airborne fraction, usually considered to be about 50 percent of the release from fossil fuels, was probably between 22 and 43 percent of the total carbon released in 1980. The increase in carbon dioxide in the atmosphere is thought by some to be increasing the storage of carbon in the earth's remaining forests sufficiently to offset the release from deforestation. The interpretation of the evidence presented here suggests no such effect; deforestation appears to be the dominant biotic effect on atmospheric carbon dioxide. If deforestation increases in proportion to population, the biotic release of carbon will reach 9 x 10(15) grams per year before forests are exhausted early in the next century. The possibilities for limiting the accumulation of carbon dioxide in the atmosphere through reduction in use of fossil fuels and through management of forests may be greater than is commonly assumed. PMID:17747369

  12. Carbon Monoxide Poisoning

    Science.gov (United States)

    ... Recommend on Facebook Tweet Share Compartir What is Carbon Monoxide? Carbon monoxide, or “CO,” is an odorless, colorless gas that can kill you. Carbon monoxide detector Where is CO found? CO is ...

  13. Net Ecosystem Carbon Flux

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — Net Ecosystem Carbon Flux is defined as the year-over-year change in Total Ecosystem Carbon Stock, or the net rate of carbon exchange between an ecosystem and the...

  14. Carbon Monoxide (CO)

    Science.gov (United States)

    ... IAQ) » Carbon Monoxide's Impact on Indoor Air Quality Carbon Monoxide's Impact on Indoor Air Quality On this ... length of exposure. Top of Page Sources of Carbon Monoxide Sources of CO include: unvented kerosene and ...

  15. Carbon cycling and storage in mangrove forests.

    Science.gov (United States)

    Alongi, Daniel M

    2014-01-01

    Mangroves are ecologically and economically important forests of the tropics. They are highly productive ecosystems with rates of primary production equal to those of tropical humid evergreen forests and coral reefs. Although mangroves occupy only 0.5% of the global coastal area, they contribute 10-15% (24 Tg C y(-1)) to coastal sediment carbon storage and export 10-11% of the particulate terrestrial carbon to the ocean. Their disproportionate contribution to carbon sequestration is now perceived as a means for conservation and restoration and a way to help ameliorate greenhouse gas emissions. Of immediate concern are potential carbon losses to deforestation (90-970 Tg C y(-1)) that are greater than these ecosystems' rates of carbon storage. Large reservoirs of dissolved inorganic carbon in deep soils, pumped via subsurface pathways to adjacent waterways, are a large loss of carbon, at a potential rate up to 40% of annual primary production. Patterns of carbon allocation and rates of carbon flux in mangrove forests are nearly identical to those of other tropical forests. PMID:24405426

  16. Carbon Cycling and Storage in Mangrove Forests

    Science.gov (United States)

    Alongi, Daniel M.

    2014-01-01

    Mangroves are ecologically and economically important forests of the tropics. They are highly productive ecosystems with rates of primary production equal to those of tropical humid evergreen forests and coral reefs. Although mangroves occupy only 0.5% of the global coastal area, they contribute 10-15% (24 Tg C y-1) to coastal sediment carbon storage and export 10-11% of the particulate terrestrial carbon to the ocean. Their disproportionate contribution to carbon sequestration is now perceived as a means for conservation and restoration and a way to help ameliorate greenhouse gas emissions. Of immediate concern are potential carbon losses to deforestation (90-970 Tg C y-1) that are greater than these ecosystems' rates of carbon storage. Large reservoirs of dissolved inorganic carbon in deep soils, pumped via subsurface pathways to adjacent waterways, are a large loss of carbon, at a potential rate up to 40% of annual primary production. Patterns of carbon allocation and rates of carbon flux in mangrove forests are nearly identical to those of other tropical forests.

  17. 10 CFR 1705.10 - Fees.

    Science.gov (United States)

    2010-01-01

    ... will be charged at the same rate established for FOIA requests. See 10 CFR 1703.107. However, the first... 10 Energy 4 2010-01-01 2010-01-01 false Fees. 1705.10 Section 1705.10 Energy DEFENSE NUCLEAR FACILITIES SAFETY BOARD PRIVACY ACT § 1705.10 Fees. A fee will not be charged for search or review...

  18. Preparation and characterization of carbon nanotube-hybridized carbon fiber to reinforce epoxy composite

    International Nuclear Information System (INIS)

    Highlights: → CNTs were uniformly grown onto the carbon fibers. → No obvious mechanical properties of carbon fiber were observed after CNT growth. → The IFSS of multiscale epoxy composite was measured by single fiber pull-out tests. → Observing fractography of composite, the fracture modes of CNTs were discussed. -- Abstract: The multiscale carbon nanotube-hybridized carbon fiber was prepared by a newly developed aerosol-assisted chemical vapour deposition. Scanning electron microscopy and transmission electron microscope were carried out to characterize this multiscale material. Compared with the original carbon fibers, the fabrication of this hybrid fiber resulted in an almost threefold increase of BET surface area to reach 2.22 m2/g. Meanwhile, there was a slight degradation of fiber tensile strength within 10%, while the fiber modulus was not significantly affected. The interfacial shearing strength of a carbon fiber-reinforced polymer composite with carbon nanotube-hybridized carbon fiber and an epoxy matrix was determined from the single fiber pull-out tests of microdroplet composite. Due to an efficient increase of load transfer at the fiber/matrix interfaces, the interracial shear strength of composite reinforced by carbon nanotube-hybridized carbon fiber is almost 94% higher than that of one reinforced by the original carbon fiber. Based on the fractured morphologies of the composites, the interfacial reinforcing mechanisms were discussed through proposing different types of carbon nanotube fracture modes along with fiber pulling out from epoxy composites.

  19. High efficient preparation of carbon nanotube-grafted carbon fibers with the improved tensile strength

    Science.gov (United States)

    Fan, Wenxin; Wang, Yanxiang; Wang, Chengguo; Chen, Jiqiang; Wang, Qifen; Yuan, Yan; Niu, Fangxu

    2016-02-01

    An innovative technique has been developed to obtain the uniform catalyst coating on continuously moving carbon fibers. Carbon nanotube (CNT)-grafted carbon fibers with significantly improved tensile strength have been succeeded to produce by using chemical vapor deposition (CVD) when compared to the tensile strength of untreated carbon fibers. The critical requirements for preparation of CNT-grafted carbon fibers with high tensile strength have been found, mainly including (i) the obtainment of uniform coating of catalyst particles with small particle size, (ii) the low catalyst-induced and mechano-chemical degradation of carbon fibers, and (iii) the high catalyst activity which could facilitate the healing and strengthening of carbon fibers during the growth of CNTs. The optimum growth temperature was found to be about 500 °C, and the optimum catalyst is Ni due to its highest activity, there is a pronounced increase of 10% in tensile strength of carbon fibers after CNT growth at 500 °C by using Ni catalyst. Based on the observation from HRTEM images, a healing and crosslink model of neighboring carbon crystals by CNTs has been formulated to reveal the main reason that causes an increase in tensile strength of carbon fibers after the growth of CNTs. Such results have provided the theoretical and experimental foundation for the large-scale preparation of CNT-grafted carbon fibers with the improved tensile strength, significantly promoting the development of CNT-grafted carbon fiber reinforced polymer composites.

  20. Integral Ring Carbon-Carbon Piston

    Science.gov (United States)

    Northam, G. Burton (Inventor)

    1999-01-01

    An improved structure for a reciprocating internal combustion engine or compressor piston fabricate from carbon-carbon composite materials is disclosed. An integral ring carbon-carbon composite piston, disclosed herein, reduces the need for piston rings and for small clearances by providing a small flexible, integral component around the piston that allows for variation in clearance due to manufacturing tolerances, distortion due to pressure and thermal loads, and variations in thermal expansion differences between the piston and cylinder liner.

  1. Carbon dioxide sequestration by mineral carbonation

    OpenAIRE

    Huijgen, W.J.J.

    2007-01-01

    The increasing atmospheric carbon dioxide (CO2) concentration, mainly caused by fossil fuel combustion, has lead to concerns about global warming. A possible technology that can contribute to the reduction of carbon dioxide emissions is CO2 sequestration by mineral carbonation. The basic concept behind mineral CO2 sequestration is the mimicking of natural weathering processes in which calcium or magnesium containing minerals react with gaseous CO2 and form solid calcium or magnesium carbonate...

  2. Ultrasound-intensified mineral carbonation

    International Nuclear Information System (INIS)

    Several aspects of ultrasound-assisted mineral carbonation were investigated in this work. The objectives were to intensify the CO2 sequestration process to improve reaction kinetics and maximal conversion. Stainless steel slags, derived from the Argon Oxygen Decarburization (AOD) and Continuous Casting/Ladle Metallurgy (CC/LM) refining steps, were used for assessing the technical feasibility of this concept, as they are potential carbon sinks and can benefit from reduction in alkalinity (pH) by mineral carbonation. Ultrasound was applied by use of an ultrasound horn into the reaction slurry, where mineral carbonation reaction took place at 50 °C for up to 4 h; comparison was made to solely mechanically mixed process. It was found that sonication increases the reaction rate after the initial stage, and permits achieving higher carbonate conversion and lower pH. AOD slag conversion increased from 30% to 49%, and pH decreased from 10.6 to 10.1; CC slag conversion increased from 61% to 73% and pH decreased from 10.8 to 9.9. The enhancement effect of ultrasound was attributed to the removal of passivating layers (precipitated calcium carbonate and depleted silica) that surround the unreacted particle core and inhibit mass transfer. Significant particle size reduction was observed for sonicated powders, compared to particle size growth in the case of stirring-only; D[4,3] values increased without sonication by 74% and 50%, and decreased with sonication by 64% and 52%, respectively for AOD and CC slags. Considerations on scale-up of this technology, particularly with regards to energy efficiency, are also discussed. Highlights: ► Ultrasound increased CaO, AOD and CC slags mineral carbonation rates and conversions. ► Enhancement effect linked to removal of mass transfer inhibiting passivating layers. ►Carbonated particle size grew with stirring-only, and decreased with sonication. ► Lower pH of slags with greater carbonation extent can reduce heavy metal leaching

  3. Carbon accumulation in arid croplands of northwest China: pedogenic carbonate exceeding organic carbon

    Science.gov (United States)

    Wang, Xiujun; Wang, Jiaping; Xu, Minggang; Zhang, Wenju; Fan, Tinglu; Zhang, Juan

    2015-06-01

    Soil carbonate (SIC) exceeds organic carbon (SOC) greatly in arid lands, thus may be important for carbon sequestration. However, field data for quantifying carbonate accumulation have been lacking. This study aims to improve our understanding of SIC dynamics and its role in carbon sequestration. We analyzed two datasets of SOC and SIC and their 13C compositions , one with over 100 soil samples collected recently from various land uses in the Yanqi Basin, Xinjiang, and the other with 18 archived soil samples from a long-term experiment (LTE) in Pingliang, Gansu. The data from the Yanqi Basin showed that SOC had a significant relationship with SIC and pedogenic carbonate (PIC); converting shrub land to cropland increased PIC stock by 5.2 kg C m-2, which was 3.6 times of that in SOC stock. The data from the LTE showed greater accumulation of PIC (21-49 g C m-2 year-1) than SOC (10-39 g C m-2 year-1) over 0-20 cm. Our study points out that intensive cropping in the arid and semi-arid regions leads to an increase in both SOC and PIC. Increasing SOC through straw organic amendments enhances PIC accumulation in the arid cropland of northwestern China.

  4. Carbon dioxide sequestration by mineral carbonation

    NARCIS (Netherlands)

    Huijgen, W.J.J.

    2007-01-01

    The increasing atmospheric carbon dioxide (CO2) concentration, mainly caused by fossil fuel combustion, has lead to concerns about global warming. A possible technology that can contribute to the reduction of carbon dioxide emissions is CO2 sequestration by mineral carbonation. The basic concept beh

  5. Biosynthesis of glycerol carbonate from glycerol by lipase in dimethyl carbonate as the solvent.

    Science.gov (United States)

    Lee, Kyung Hwa; Park, Chang-Ho; Lee, Eun Yeol

    2010-11-01

    Glycerol carbonate was synthesized from renewable glycerol and dimethyl carbonate using lipase in solvent-free reaction system in which excess dimethyl carbonate played as the reaction medium. A variety of lipases have been tested for their abilities to catalyze transesterification reaction, and Candida antartica lipase B and Novozyme 435 exhibited higher catalytic activities. The silica-coated glycerol with a 1:1 ratio was supplied to prevent two-phase formation between hydrophobic dimethyl carbonate and hydrophilic glycerol. Glycerol carbonate was successfully synthesized with more than 90% conversion from dimethyl carbonate and glycerol with a molar ratio of 10 using Novozyme 435-catalyzed transesterification at 70 °C. The Novozyme 435 [5% (w/w) and 20% (w/w)] and silica gel were more than four times recycled with good stability in a repeated batch operation for the solvent-free synthesis of glycerol carbonate. PMID:20502921

  6. Dissolved inorganic carbon, total alkalinity, pH, and other variables collected from surface discrete observations using spectrophotometer and other instruments from R/V Henry B. Bigelow off the northeastern coast of the United States from 2014-09-10 to 2014-11-05 (NCEI Accession 0138983)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Increasing amounts of atmospheric carbon dioxide from human industrial activities are causing changes in global ocean carbon chemistry resulting in a reduction in...

  7. Composite carbon foam electrode

    Science.gov (United States)

    Mayer, S.T.; Pekala, R.W.; Kaschmitter, J.L.

    1997-05-06

    Carbon aerogels used as a binder for granulated materials, including other forms of carbon and metal additives, are cast onto carbon or metal fiber substrates to form composite carbon thin film sheets. The thin film sheets are utilized in electrochemical energy storage applications, such as electrochemical double layer capacitors (aerocapacitors), lithium based battery insertion electrodes, fuel cell electrodes, and electrocapacitive deionization electrodes. The composite carbon foam may be formed by prior known processes, but with the solid particles being added during the liquid phase of the process, i.e. prior to gelation. The other forms of carbon may include carbon microspheres, carbon powder, carbon aerogel powder or particles, graphite carbons. Metal and/or carbon fibers may be added for increased conductivity. The choice of materials and fibers will depend on the electrolyte used and the relative trade off of system resistivity and power to system energy. 1 fig.

  8. 10 lessons from 10 years of the CDM

    OpenAIRE

    Shishlov, Igor; Bellassen, Valentin

    2012-01-01

    The Clean Development Mechanism (CDM) is the first and by far the largest carbon offset instrument in the world. To date, it is the only market based on an environmental commodity which managed to attract several billions of euros of private capital on an annual basis. Being the first-of-a-kind climate change mitigation instrument, the CDM followed a "learning by doing" pattern undergoing numerous reforms throughout its more than 10-year history. Although the post-2012 fate of the mechanism r...

  9. 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

  10. Scale-up of Carbon/Carbon Bipolar Plates

    Energy Technology Data Exchange (ETDEWEB)

    David P. Haack

    2009-04-08

    This project was focused upon developing a unique material technology for use in PEM fuel cell bipolar plates. The carbon/carbon composite material developed in this program is uniquely suited for use in fuel cell systems, as it is lightweight, highly conductive and corrosion resistant. The project further focused upon developing the manufacturing methodology to cost-effectively produce this material for use in commercial fuel cell systems. United Technology Fuel Cells Corp., a leading fuel cell developer was a subcontractor to the project was interested in the performance and low-cost potential of the material. The accomplishments of the program included the development and testing of a low-cost, fully molded, net-shape carbon-carbon bipolar plate. The process to cost-effectively manufacture these carbon-carbon bipolar plates was focused on extensively in this program. Key areas for cost-reduction that received attention in this program was net-shape molding of the detailed flow structures according to end-user design. Correlations between feature detail and process parameters were formed so that mold tooling could be accurately designed to meet a variety of flow field dimensions. A cost model was developed that predicted the cost of manufacture for the product in near-term volumes and long-term volumes (10+ million units per year). Because the roduct uses lowcost raw materials in quantities that are less than competitive tech, it was found that the cost of the product in high volume can be less than with other plate echnologies, and can meet the DOE goal of $4/kW for transportation applications. The excellent performance of the all-carbon plate in net shape was verified in fuel cell testing. Performance equivalent to much higher cost, fully machined graphite plates was found.

  11. 10 CFR 904.10 - Excess energy.

    Science.gov (United States)

    2010-01-01

    ... 10 Energy 4 2010-01-01 2010-01-01 false Excess energy. 904.10 Section 904.10 Energy DEPARTMENT OF ENERGY GENERAL REGULATIONS FOR THE CHARGES FOR THE SALE OF POWER FROM THE BOULDER CANYON PROJECT Power Marketing § 904.10 Excess energy. (a) If excess Energy is determined by the United States to be...

  12. Piezoresistive Sensors Based on Carbon Nanotube Films

    Institute of Scientific and Technical Information of China (English)

    L(U) Jian-wei; WANG Wan-lu; LIAO Ke-jun; WANG Yong-tian; LIU CHang-lin; Zeng Qing-gao

    2005-01-01

    Piezoresistive effect of carbon nanotube films was investigated by a three-point bending test.Carbon nanotubes were synthesized by hot filament chemical vapor deposition.The experimental results showed that the carbon nanotubes have a striking piezoresistive effect.The relative resistance was changed from 0 to 10.5×10-2 and 3.25×10-2 for doped and undoped films respectively at room temperature when the microstrain under stress from 0 to 500. The gauge factors for doped and undoped carbon nanotube films under 500 microstrain were about 220 and 67 at room temperature, respectively, exceeding that of polycrystalline silicon (30) at 35℃.The origin of the resistance changes in the films may be attributed to a strain-induced change in the band gap for the doped tubes and the defects for the undoped tubes.

  13. 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)

  14. Does soil fauna increase carbon mineralization or carbon sequestration in soil

    Czech Academy of Sciences Publication Activity Database

    Frouz, Jan

    České Budějovice : Institute of Soil Biology BC AS CR, 2009. s. 22. [Central European Workshop on Soil Zoology /10./. 21.04.2009-24.04.2009, České Budějovice] Institutional research plan: CEZ:AV0Z60660521 Keywords : soil fauna * carbon mineralization * carbon sequestration Subject RIV: EH - Ecology, Behaviour

  15. Mutagenicity of carbon nanomaterials

    DEFF Research Database (Denmark)

    Wallin, Håkan; Jacobsen, Nicklas Raun; White, Paul A;

    2011-01-01

    Carbon nanomaterials such carbon nanotubes, graphene and fullerenes are some the most promising nanomaterials. Although carbon nanomaterials have been reported to possess genotoxic potential, it is imperitive to analyse the data on the genotoxicity of carbon nanomaterials in vivo and in vitro and...

  16. Electroanalysis with carbon paste electrodes

    CERN Document Server

    Svancara, Ivan; Walcarius, Alain; Vytras, Karel

    2011-01-01

    Introduction to Electrochemistry and Electroanalysis with Carbon Paste-Based ElectrodesHistorical Survey and GlossaryField in Publication Activities and LiteratureCarbon Pastes and Carbon Paste ElectrodesCarbon Paste as the Binary MixtureClassification of Carbon Pastes and Carbon Paste ElectrodesConstruction of Carbon Paste HoldersCarbon Paste as the Electrode MaterialPhysicochemical Properties of Carbon PastesElectrochemical Characteristics of Carbon PastesTesting of Unmodified CPEsIntera

  17. Pyrolyzed thin film carbon

    Science.gov (United States)

    Tai, Yu-Chong (Inventor); Liger, Matthieu (Inventor); Harder, Theodore (Inventor); Konishi, Satoshi (Inventor); Miserendino, Scott (Inventor)

    2010-01-01

    A method of making carbon thin films comprises depositing a catalyst on a substrate, depositing a hydrocarbon in contact with the catalyst and pyrolyzing the hydrocarbon. A method of controlling a carbon thin film density comprises etching a cavity into a substrate, depositing a hydrocarbon into the cavity, and pyrolyzing the hydrocarbon while in the cavity to form a carbon thin film. Controlling a carbon thin film density is achieved by changing the volume of the cavity. Methods of making carbon containing patterned structures are also provided. Carbon thin films and carbon containing patterned structures can be used in NEMS, MEMS, liquid chromatography, and sensor devices.

  18. 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.

  19. 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.''

  20. Wood - a carbon depot

    OpenAIRE

    Lipušček, Igor; Tišler, Vesna

    2003-01-01

    The article examines the global movement of carbon dioxide, the most important greenhouse gas due to its large quantities. We studied the carbon cycle with possibilities of its extension, and analysed the mechanisms that remove carbon dioxide from the atmosphere and bind it into solid substances for a longer period of time. The focus was on carbon dioxide sink into biomass and carbon deposit in wood. On the basis of wood component data and chemical analysis of the components, we calculated th...

  1. Carbon allocation, sequestration and carbon dioxide mitigation under plantation forests of north western Himalaya, India

    Directory of Open Access Journals (Sweden)

    Bandana Devi

    2013-05-01

    Full Text Available The organic carbon and soils of the world comprise bulk of the terrestrial carbon and serve as a major sink and source of atmospheric carbon. Increasing atmospheric concentrations of green house gases may be mitigated by increasing carbon sequestration in vegetation and soil. The study attempted to estimate biomass production and carbon sequestration potential of different plantation ecosystems in north western Himalaya, India. Biomass, carbon density of biomass, soil, detritus, carbon sequestration and CO2 mitigation potential were studied under different plantation forest ecosystems comprising of eight different tree species: Quercus leucotrichophora, Pinus roxburghii, Acacia catechu, Acacia mollissima, Albizia procera, Alnusnitida, Eucalyptus tereticornis and Ulmus villosa. Above (185.57±48.99tha-1 and below ground (42.47±10.38 tha-1 biomass was maximum in Ulmus villosa. The vegetation carbon density was maxium in Albizia procera(118.37±1.49 tha-1 and minimum (36.50±9.87 tha-1 in Acacia catechu. Soil carbon density was maximum (219.86±10.34 tha-1 in Alnus nitida, and minimum (170.83±20.60 tha-1 in Pinus roxburghii. Detritus was higher in Pinus roxburghii (6.79±2.0 tha-1. Carbon sequestration (7.91±3.4 tha-1 and CO2 mitigation potential (29.09±12.78 tha-1 was maximum in Ulmus villosa. Pearson correlation matrix revealed significant positive relationship of ecosystem carbon with plantation biomass, soil carbon and CO2 mitigation potential. With the emerging threat of climate change, such assessment of forest and soil carbon inventory would allow to devise best land management and policy decisions for sustainable management of fragile hilly ecosystem.

  2. Carbon allocation, sequestration and carbon dioxide mitigation under plantation forests of north western Himalaya, India

    Directory of Open Access Journals (Sweden)

    Bandana Devi

    2013-07-01

    Full Text Available The organic carbon and soils of the world comprise bulk of the terrestrial carbon and serve as amajorsink and source of atmospheric carbon. Increasing atmospheric concentrations of green house gases may be mitigated by increasing carbon sequestration in vegetation and soil. The study attempted to estimate biomass production and carbon sequestration potential of different plantation ecosystems in north western Himalaya, India. Biomass, carbon density of biomass, soil, detritus, carbon sequestration and CO2 mitigation potential were studied underdifferent plantation forest ecosystems comprising of eight different tree species viz. Quercus leucotrichophora, Pinus roxburghii, Acacia catechu, Acacia mollissima, Albizia procera, Alnus nitida, Eucalyptus tereticornis and Ulmus villosa. Above (185.57 ą 48.99 tha-1 and below ground (42.47 ą 10.38 tha-1 biomass was maximum in Ulmus villosa. The vegetation carbon density was maxium in Albizia procera (118.37 ą 1.49 tha-1 and minimum (36.50 ą 9.87 tha-1 in Acacia catechu. Soil carbon density was maximum (219.86ą 10.34 tha-1 in Alnus nitida, and minimum (170.83ą 20.60 tha-1in Pinus roxburghii. Detritus was higher in Pinus roxburghii (6.79 ą 2.0 tha-1. Carbon sequestration (7.91ą 3.4 tha-1 and CO2 mitigation potential (29.09 ą 12.78 tha-1 was maximum in Ulmus villosa. Pearson correlation matrix revealed significant positive relationship of ecosystem carbon with plantation biomass, soil carbon and CO2 mitigation potential. With the emerging threat of climate change, such assessment of forest and soil carbon inventory would allow to devise best land management and policy decisions forsustainable management of fragile hilly ecosystem. 

  3. Global carbon budget 2014

    Science.gov (United States)

    Le Quéré, C.; Moriarty, R.; Andrew, R. M.; Peters, G. P.; Ciais, P.; Friedlingstein, P.; Jones, S. D.; Sitch, S.; Tans, P.; Arneth, A.; Boden, T. A.; Bopp, L.; Bozec, Y.; Canadell, J. G.; Chini, L. P.; Chevallier, F.; Cosca, C. E.; Harris, I.; Hoppema, M.; Houghton, R. A.; House, J. I.; Jain, A. K.; Johannessen, T.; Kato, E.; Keeling, R. F.; Kitidis, V.; Klein Goldewijk, K.; Koven, C.; Landa, C. S.; Landschützer, P.; Lenton, A.; Lima, I. D.; Marland, G.; Mathis, J. T.; Metzl, N.; Nojiri, Y.; Olsen, A.; Ono, T.; Peng, S.; Peters, W.; Pfeil, B.; Poulter, B.; Raupach, M. R.; Regnier, P.; Rödenbeck, C.; Saito, S.; Salisbury, J. E.; Schuster, U.; Schwinger, J.; Séférian, R.; Segschneider, J.; Steinhoff, T.; Stocker, B. D.; Sutton, A. J.; Takahashi, T.; Tilbrook, B.; van der Werf, G. R.; Viovy, N.; Wang, Y.-P.; Wanninkhof, R.; Wiltshire, A.; Zeng, N.

    2015-05-01

    component of the global carbon budget. For the last decade available (2004-2013), EFF was 8.9 ± 0.4 GtC yr-1, ELUC 0.9 ± 0.5 GtC yr-1, GATM 4.3 ± 0.1 GtC yr-1, SOCEAN 2.6 ± 0.5 GtC yr-1, and SLAND 2.9 ± 0.8 GtC yr-1. For year 2013 alone, EFF grew to 9.9 ± 0.5 GtC yr-1, 2.3% above 2012, continuing the growth trend in these emissions, ELUC was 0.9 ± 0.5 GtC yr-1, GATM was 5.4 ± 0.2 GtC yr-1, SOCEAN was 2.9 ± 0.5 GtC yr-1, and SLAND was 2.5 ± 0.9 GtC yr-1. GATM was high in 2013, reflecting a steady increase in EFF and smaller and opposite changes between SOCEAN and SLAND compared to the past decade (2004-2013). The global atmospheric CO2 concentration reached 395.31 ± 0.10 ppm averaged over 2013. We estimate that EFF will increase by 2.5% (1.3-3.5%) to 10.1 ± 0.6 GtC in 2014 (37.0 ± 2.2 GtCO2 yr-1), 65% above emissions in 1990, based on projections of world gross domestic product and recent changes in the carbon intensity of the global economy. From this projection of EFF and assumed constant ELUC for 2014, cumulative emissions of CO2 will reach about 545 ± 55 GtC (2000 ± 200 GtCO2) for 1870-2014, about 75% from EFF and 25% from ELUC. This paper documents changes in the methods and data sets used in this new carbon budget compared with previous publications of this living data set (Le Quéré et al., 2013, 2014). All observations presented here can be downloaded from the Carbon Dioxide Information Analysis Center (doi:10.3334/CDIAC/GCP_2014).

  4. On the Carbon-Star Status of Five Stars in a New Carbon Star Catalog

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    We find that five sources listed in the new carbon star catalog are not really carbon-rich objects but oxygen-rich stars, because they all have the prominent 10μm silicate features in absorption and the 1612 MHz OH maser emission or/and the SiO molecular features. These objects were considered as carbon stars in the catalog based only on their locations in the infrared two-color diagram. Therefore to use the infrared two-color diagram to distinguish carbon-rich stars from oxygenrich stars must be done with caution, because, in general, it has only a statistical meaning.

  5. Effect of Elevated Carbon Dioxide Concentration on Carbon Assimilation under Fluctuating Light

    Czech Academy of Sciences Publication Activity Database

    Holišová, Petra; Zitová, Martina; Klem, Karel; Urban, Otmar

    2012-01-01

    Roč. 41, č. 6 (2012), s. 1931-1938. ISSN 0047-2425 R&D Projects: GA MŠk(CZ) ED1.1.00/02.0073; GA ČR(CZ) GAP501/10/0340; GA MŠk(CZ) LM2010007; GA AV ČR IAA600870701 Institutional support: RVO:67179843 Keywords : carbon * light * beech * spruce * carbon assimilation * elevate carbon * dioxide concentration * mol * photosynthetic * assimilation * carbon dioxide * dioxide * concentracion * leave * photosynthetic efficiency Subject RIV: EH - Ecology, Behaviour Impact factor: 2.353, year: 2012

  6. Mechanical Properties of Resin-Based Carbon-Carbon Composites Modified with Needle Coke

    Czech Academy of Sciences Publication Activity Database

    Balík, Karel; Gregor, Jiří; Černý, Martin; Klučáková, Martina

    Singapore : World Scientific, 1996 - (Palmer, K.; Marx , D.; Wright, M.), s. 371-379 ISBN 981-02-2801-5. [Carbon and Carbonaceous Composite Materials: Structure-Property Relationships. Malenovice (CZ), 10.10.1995-13.10.1995] R&D Projects: GA ČR GA104/94/1789

  7. Key roles of carbon solubility in single-walled carbon nanotube nucleation and growth

    Science.gov (United States)

    He, Maoshuai; Amara, Hakim; Jiang, Hua; Hassinen, Jukka; Bichara, Christophe; Ras, Robin H. A.; Lehtonen, Juha; Kauppinen, Esko I.; Loiseau, Annick

    2015-11-01

    Elucidating the roles played by carbon solubility in catalyst nanoparticles is required to better understand the growth mechanisms of single-walled carbon nanotubes (SWNTs). Here, we highlight that controlling the level of dissolved carbon is of key importance to enable nucleation and growth. We first performed tight binding based atomistic computer simulations to study carbon incorporation in metal nanoparticles with low solubilities. For such metals, carbon incorporation strongly depends on their structures (face centered cubic or icosahedral), leading to different amounts of carbon close to the nanoparticle surface. Following this idea, we then show experimentally that Au nanoparticles effectively catalyze SWNT growth when in a face centered cubic structure, and fail to do so when icosahedral. Both approaches emphasize that the presence of subsurface carbon in the nanoparticles is necessary to enable the cap lift-off, making the nucleation of SWNTs possible.Elucidating the roles played by carbon solubility in catalyst nanoparticles is required to better understand the growth mechanisms of single-walled carbon nanotubes (SWNTs). Here, we highlight that controlling the level of dissolved carbon is of key importance to enable nucleation and growth. We first performed tight binding based atomistic computer simulations to study carbon incorporation in metal nanoparticles with low solubilities. For such metals, carbon incorporation strongly depends on their structures (face centered cubic or icosahedral), leading to different amounts of carbon close to the nanoparticle surface. Following this idea, we then show experimentally that Au nanoparticles effectively catalyze SWNT growth when in a face centered cubic structure, and fail to do so when icosahedral. Both approaches emphasize that the presence of subsurface carbon in the nanoparticles is necessary to enable the cap lift-off, making the nucleation of SWNTs possible. Electronic supplementary information (ESI

  8. Carbon fuel cells with carbon corrosion suppression

    Science.gov (United States)

    Cooper, John F.

    2012-04-10

    An electrochemical cell apparatus that can operate as either a fuel cell or a battery includes a cathode compartment, an anode compartment operatively connected to the cathode compartment, and a carbon fuel cell section connected to the anode compartment and the cathode compartment. An effusion plate is operatively positioned adjacent the anode compartment or the cathode compartment. The effusion plate allows passage of carbon dioxide. Carbon dioxide exhaust channels are operatively positioned in the electrochemical cell to direct the carbon dioxide from the electrochemical cell.

  9. Carbon nanotube biconvex microcavities

    Energy Technology Data Exchange (ETDEWEB)

    Butt, Haider, E-mail: h.butt@bham.ac.uk; Ahmed, Rajib [Nanotechnology Laboratory, School of Mechanical Engineering, University of Birmingham, Birmingham B15 2TT (United Kingdom); Yetisen, Ali K.; Yun, Seok Hyun [Harvard Medical School and Wellman Center for Photomedicine, Massachusetts General Hospital, 50 Blossom Street, Boston, Massachusetts 02114 (United States); Dai, Qing [National Center for Nanoscience and Technology, Beijing 100190 (China)

    2015-03-23

    Developing highly efficient microcavities with predictive narrow-band resonance frequencies using the least amount of material will allow the applications in nonlinear photonic devices. We have developed a microcavity array that comprised multi-walled carbon nanotubes (MWCNT) organized in a biconvex pattern. The finite element model allowed designing microcavity arrays with predictive transmission properties and assessing the effects of the microarray geometry. The microcavity array demonstrated negative index and produced high Q factors. 2–3 μm tall MWCNTs were patterned as biconvex microcavities, which were separated by 10 μm in an array. The microcavity was iridescent and had optical control over the diffracted elliptical patterns with a far-field pattern, whose properties were predicted by the model. It is anticipated that the MWCNT biconvex microcavities will have implications for the development of highly efficient lenses, metamaterial antennas, and photonic circuits.

  10. Global Carbon Budget 2015

    Science.gov (United States)

    Le Quéré, C.; Moriarty, R.; Andrew, R. M.; Canadell, J. G.; Sitch, S.; Korsbakken, J. I.; Friedlingstein, P.; Peters, G. P.; Andres, R. J.; Boden, T. A.; Houghton, R. A.; House, J. I.; Keeling, R. F.; Tans, P.; Arneth, A.; Bakker, D. C. E.; Barbero, L.; Bopp, L.; Chang, J.; Chevallier, F.; Chini, L. P.; Ciais, P.; Fader, M.; Feely, R. A.; Gkritzalis, T.; Harris, I.; Hauck, J.; Ilyina, T.; Jain, A. K.; Kato, E.; Kitidis, V.; Klein Goldewijk, K.; Koven, C.; Landschützer, P.; Lauvset, S. K.; Lefèvre, N.; Lenton, A.; Lima, I. D.; Metzl, N.; Millero, F.; Munro, D. R.; Murata, A.; Nabel, J. E. M. S.; Nakaoka, S.; Nojiri, Y.; O'Brien, K.; Olsen, A.; Ono, T.; Pérez, F. F.; Pfeil, B.; Pierrot, D.; Poulter, B.; Rehder, G.; Rödenbeck, C.; Saito, S.; Schuster, U.; Schwinger, J.; Séférian, R.; Steinhoff, T.; Stocker, B. D.; Sutton, A. J.; Takahashi, T.; Tilbrook, B.; van der Laan-Luijkx, I. T.; van der Werf, G. R.; van Heuven, S.; Vandemark, D.; Viovy, N.; Wiltshire, A.; Zaehle, S.; Zeng, N.

    2015-12-01

    carbon budget. For the last decade available (2005-2014), EFF was 9.0 ± 0.5 GtC yr-1, ELUC was 0.9 ± 0.5 GtC yr-1, GATM was 4.4 ± 0.1 GtC yr-1, SOCEAN was 2.6 ± 0.5 GtC yr-1, and SLAND was 3.0 ± 0.8 GtC yr-1. For the year 2014 alone, EFF grew to 9.8 ± 0.5 GtC yr-1, 0.6 % above 2013, continuing the growth trend in these emissions, albeit at a slower rate compared to the average growth of 2.2 % yr-1 that took place during 2005-2014. Also, for 2014, ELUC was 1.1 ± 0.5 GtC yr-1, GATM was 3.9 ± 0.2 GtC yr-1, SOCEAN was 2.9 ± 0.5 GtC yr-1, and SLAND was 4.1 ± 0.9 GtC yr-1. GATM was lower in 2014 compared to the past decade (2005-2014), reflecting a larger SLAND for that year. The global atmospheric CO2 concentration reached 397.15 ± 0.10 ppm averaged over 2014. For 2015, preliminary data indicate that the growth in EFF will be near or slightly below zero, with a projection of -0.6 [range of -1.6 to +0.5] %, based on national emissions projections for China and the USA, and projections of gross domestic product corrected for recent changes in the carbon intensity of the global economy for the rest of the world. From this projection of EFF and assumed constant ELUC for 2015, cumulative emissions of CO2 will reach about 555 ± 55 GtC (2035 ± 205 GtCO2) for 1870-2015, about 75 % from EFF and 25 % from ELUC. This living data update documents changes in the methods and data sets used in this new carbon budget compared with previous publications of this data set (Le Quéré et al., 2015, 2014, 2013). All observations presented here can be downloaded from the Carbon Dioxide Information Analysis Center (doi:10.3334/CDIAC/GCP_2015).

  11. Supercapacitors based on carbon foams

    Science.gov (United States)

    Kaschmitter, J.L.; Mayer, S.T.; Pekala, R.W.

    1993-11-09

    A high energy density capacitor incorporating a variety of carbon foam electrodes is described. The foams, derived from the pyrolysis of resorcinol-formaldehyde and related polymers, are high density (0.1 g/cc-1.0 g/cc) electrically conductive and have high surface areas (400 m[sup 2]/g-1000 m[sup 2]/g). Capacitances on the order of several tens of farad per gram of electrode are achieved. 9 figures.

  12. Patterned functional carbon fibers from polyethylene

    Energy Technology Data Exchange (ETDEWEB)

    Hunt, Marcus A [ORNL; Saito, Tomonori [ORNL; Brown, Rebecca H [ORNL; Kumbhar, Amar S [University of North Carolina, Chapel Hill; Naskar, Amit K [ORNL

    2012-01-01

    Patterned, continuous carbon fibers with controlled surface geometry were produced from a novel melt-processible carbon precursor. This portends the use of a unique technique to produce such technologically innovative fibers in large volume for important applications. The novelties of this technique include ease of designing and fabricating fibers with customized surface contour, the ability to manipulate filament diameter from submicron scale to a couple of orders of magnitude larger scale, and the amenable porosity gradient across the carbon wall by diffusion controlled functionalization of precursor. The geometry of fiber cross-section was tailored by using bicomponent melt-spinning with shaped dies and controlling the melt-processing of the precursor polymer. Circular, trilobal, gear-shaped hollow fibers, and solid star-shaped carbon fibers of 0.5 - 20 um diameters, either in self-assembled bundle form, or non-bonded loose filament form, were produced by carbonizing functionalized-polyethylene fibers. Prior to carbonization, melt-spun fibers were converted to a char-forming mass by optimizing the sulfonation on polyethylene macromolecules. The fibers exhibited distinctly ordered carbon morphologies at the outside skin compared to the inner surface or fiber core. Such order in carbon microstructure can be further tuned by altering processing parameters. Partially sulfonated polyethylene-derived hollow carbon fibers exhibit 2-10 fold surface area (50-500 m2/g) compared to the solid fibers (10-25 m2/g) with pore sizes closer to the inside diameter of the filaments larger than the sizes on the outer layer. These specially functionalized carbon fibers hold promise for extraordinary performance improvements when used, for example, as composite reinforcements, catalyst support media, membranes for gas separation, CO2 sorbents, and active electrodes and current collectors for energy storage applications.

  13. The Photochemical Stability of Carbonates on Mars

    Science.gov (United States)

    Quinn, Richard; Zent, Aaron P.; McKay, Christopher P.

    2006-08-01

    Carbonates, predominately MgCO3, have been spectroscopically identified at a level of 2-5% in martian dust. However, in spite of this observation, and a large number of climate studies that suggest 1 to several bars of CO2 should be sequestered in carbonate rocks, no outcropscale exposures of carbonate have been detected anywhere on Mars to date. To address one hypothesis for this long-standing puzzle, the effect of ultraviolet (UV) light on the stability of calcium carbonate in a simulated martian atmosphere was experimentally investigated. Using 13C-labeled calcite, we found no experimental evidence of the UV photodecomposition of calcium carbonate in a simulated martian atmosphere. Extrapolating the lower limit of detection of our experimental system to an upper limit of carbonate decomposition on Mars yields a quantum efficiency of 3.5 × 10-8 molecules/photon over the wavelength interval of 190-390 nm and a maximum UV photodecomposition rate of 1.2 × 10-13 kg m-2 s-1 from a calcite surface. The maximum loss of bulk calcite due to this process would be 2.5 nm year-1 (Mars year). However, calcite is expected to be thermodynamically stable on the surface of Mars, and potential UV photodecomposition reaction mechanisms indicate that, though calcium carbonate may decompose under vacuum, it would be stable in a CO2 atmosphere. Given the expected stability of carbonate on Mars and our inability to detect carbonate decomposition, we conclude that it is unlikely that the apparent absence of extensive carbonate deposits on the martian surface is due to UV photodecomposition in the current environment.

  14. Seagrass restoration enhances "blue carbon" sequestration in coastal waters.

    Directory of Open Access Journals (Sweden)

    Jill T Greiner

    Full Text Available Seagrass meadows are highly productive habitats that provide important ecosystem services in the coastal zone, including carbon and nutrient sequestration. Organic carbon in seagrass sediment, known as "blue carbon," accumulates from both in situ production and sedimentation of particulate carbon from the water column. Using a large-scale restoration (>1700 ha in the Virginia coastal bays as a model system, we evaluated the role of seagrass, Zosteramarina, restoration in carbon storage in sediments of shallow coastal ecosystems. Sediments of replicate seagrass meadows representing different age treatments (as time since seeding: 0, 4, and 10 years, were analyzed for % carbon, % nitrogen, bulk density, organic matter content, and ²¹⁰Pb for dating at 1-cm increments to a depth of 10 cm. Sediment nutrient and organic content, and carbon accumulation rates were higher in 10-year seagrass meadows relative to 4-year and bare sediment. These differences were consistent with higher shoot density in the older meadow. Carbon accumulation rates determined for the 10-year restored seagrass meadows were 36.68 g C m⁻² yr⁻¹. Within 12 years of seeding, the restored seagrass meadows are expected to accumulate carbon at a rate that is comparable to measured ranges in natural seagrass meadows. This the first study to provide evidence of the potential of seagrass habitat restoration to enhance carbon sequestration in the coastal zone.

  15. Electromagnetic physical modeling. 10; Denji yudoho no model jikken. 10

    Energy Technology Data Exchange (ETDEWEB)

    Noguchi, K.; Endo, M.; Yoshimori, M. [Waseda University, Tokyo (Japan). School of Science and Engineering; Saito, A. [Mitsui Mineral Development Engineering Co. Ltd., Tokyo (Japan)

    1996-10-01

    The model experiment of a borehole electromagnetic (EM) method was carried out using the prepared waterproof sensor and materials with conductivity of 10{sup 0}-10{sup 2}S/m as medium. The 2-layered structure ground model was prepared by filling a water tank with saturated brine of nearly 20S/m up to 30cm. Square wave current was sent from an amplifier to a transmitter coil, and electro motive force induced in a receiver coil was measured. Although numerical simulation is widely used for EM method, analog model experiment is also effective. For the receiver coil installed in brine, preventive measures from short-circuit and water were prepared. Electro motive force was measured at receiver intervals of 1cm and at 0-10cm in depth using a bar carbon model immersed in brine by 5cm in depth under resistivity contrast of 1000 times. In addition, to reduce the resistivity contrast between brine and body, the model experiment was carried out using immersed thin metallic sheet structure with conductivity similar to that of ore under resistivity contrast of 250 times. The effect of medium on both models was thus clarified. 4 refs., 10 figs.

  16. Bis(adamantan-1-aminium carbonate

    Directory of Open Access Journals (Sweden)

    Monika Nowakowska

    2012-04-01

    Full Text Available In the title compound, 2C10H18N+·CO32−, the adamantan-1-aminium cation forms three N—H...O hydrogen bonds to three carbonate ions, resulting in a layer parallel to (001 with the adamantane groups located on its surface so that adjacent layers form only C—H...H—C contacts. The carbonate anions occupy special positions of 32 symmetry, whereas the adamantan-1-aminium cations occupy special positions of 3 symmetry.

  17. Enhanced fluid flow through nanoscale carbon pipes.

    Science.gov (United States)

    Whitby, Max; Cagnon, Laurent; Thanou, Maya; Quirke, Nick

    2008-09-01

    Recent experimental and theoretical studies demonstrate that pressure driven flow of fluids through nanoscale ( d < 10 nm) carbon pores occurs 4 to 5 orders of magnitude faster than predicted by extrapolation from conventional theory. Here, we report experimental results for flow of water, ethanol, and decane through carbon nanopipes with larger inner diameters (43 +/- 3 nm) than previously investigated. We find enhanced transport up to 45 times theoretical predictions. In contrast to previous work, in our systems, decane flows faster than water. These nanopipes were composed of amorphous carbon deposited from ethylene vapor in alumina templates using a single step fabrication process. PMID:18680352

  18. Superelastic carbon spheres under high pressure

    Science.gov (United States)

    Li, Meifen; Guo, Junjie; Xu, Bingshe

    2013-03-01

    We report a superelastic deformation behavior of carbon spheres by the in situ Raman spectroscopy in a high-pressure diamond anvil cell. The carbon spheres produced by arc discharging in toluene have a mean diameter of 200 nm and an onion-like multilayer graphitic structure. We find that the elastic coefficients, during both the compression and decompression processes, remain a constant up to 10 GPa, indicating a superior high-pressure structural stability. Such superelastic behavior is related to the isotropic and concentric configuration of carbon spheres and provides additional insight into improving the microscopic mechanical properties of small-scale particles.

  19. Nanostructured carbon films with oriented graphitic planes

    International Nuclear Information System (INIS)

    Nanostructured carbon films with oriented graphitic planes can be deposited by applying energetic carbon bombardment. The present work shows the possibility of structuring graphitic planes perpendicular to the substrate in following two distinct ways: (i) applying sufficiently large carbon energies for deposition at room temperature (E>10 keV), (ii) utilizing much lower energies for deposition at elevated substrate temperatures (T>200 deg. C). High resolution transmission electron microscopy is used to probe the graphitic planes. The alignment achieved at elevated temperatures does not depend on the deposition angle. The data provides insight into the mechanisms leading to the growth of oriented graphitic planes under different conditions.

  20. EDF Group reduces its carbon footprint

    International Nuclear Information System (INIS)

    Although EDF's carbon footprint in France is already very low (40 g of CO2/kWh) compared to coal-fired units (about 20 times more) or even to gas-fired combined cycles (about 10 times more), its stakes in fossil-fired power plants in Europe and overseas contribute to a total amount of 64 million tonnes of CO2 emissions per year. Therefore, reduction of carbon emissions represents a real challenge; besides demand side management, renewable developments, efficiency improvement, fuel switching from coal to gas and contribution to the nuclear revival. CCS (Carbon Capture and Storage) technologies development is also part of the picture. (orig.)

  1. Carbon nanotube cathode with capping carbon nanosheet

    Science.gov (United States)

    Li, Xin; Zhao, Dengchao; Pang, Kaige; Pang, Junchao; Liu, Weihua; Liu, Hongzhong; Wang, Xiaoli

    2013-10-01

    Here, we report a vertically aligned carbon nanotube (VACNT) film capped with a few layer of carbon nanosheet (FLCN) synthesized by chemical vapor deposition using a carbon source from iron phthalocyanine pyrolysis. The square resistance of the VACNT film is significantly reduced from 1500 Ω/□ to 300 Ω/□ when it is capped with carbon nanosheet. The VACNT capped with carbon nanosheet was transferred to an ITO glass substrate in an inverted configuration so that the carbon nanosheet served as a flexible transparent electrode at the bottom and the VACNT roots served as emission tips. Because all of the VACNTs start growing from a flat silicon substrate, the VACNT roots are very neat and uniform in height. A field emission test of the carbon nanosheet-capped VACNT film proved that the CNT roots show better uniformity in field emission and the carbon nanosheet cap could also potentially serve as a flexible transparent electrode, which is highly desired in photo-assisted field emission.

  2. Factors effecting carbonate equilibria in natural waters

    International Nuclear Information System (INIS)

    This study is related to preliminary stie evaluations to be carried out in 1987-1992 for spent nuclear fuel disposal in Finland. Near surface and shallow groundwaters are characterized by high concentration of calcium and bicarbonate due to dissolution of calcite. The input of carbon dioxide in the upper zone of the bedrock has a strong influence on the pH giving a pH around neutral. In deep groundwaters when the system is no longer open to the input of carbon dioxide the pH rises as the carbonate system is displaced towards the bicarbonate-carbonate site. In still deeper parts of the rock weathering of other minerals such as feldspars affects the chemistry raising the pH and resulting in saturation and precipitation of calcite. The more advanced these reactions become the higher is the pH and the lower is the carbonate content. The equilibrium concentrations of carbonate species are affected both by temperature and ionic strength of the waters, at high ionic strength especially the distribution between bicarbonate and carbonate ions is affected. The total concentration of carbonates in groundwaters is determined through complex interaction between calcite and carbonates in the water. In deep groundwaters which are closed for input of CO2 the concentration is stated to be regulated by dissolution of calcium carbonate. In deep granitic groundwaters pH is stated to be buffered to 6.5 to 10, where a high pH would correspond to a low total carbonate concentration and often also a low calcium concentration and a low pH would correspond to high carbonae and calcium concentrations

  3. Physical and electrochemical properties of supercapacitor composite electrodes prepared from biomass carbon and carbon from green petroleum coke

    Science.gov (United States)

    Awitdrus, Deraman, M.; Talib, I. A.; Farma, R.; Omar, R.; Ishak, M. M.; Taer, E.; Dolah, B. N. M.; Basri, N. H.; Nor, N. S. M.

    2015-04-01

    The green monoliths (GMs) were prepared from the mixtures of pre-carbonized fibers of oil palm empty fruit bunches (or self-adhesive carbon grains (SACG)) and green petroleum coke (GPC) with the mixing ratio of 0, 10, 30, 50 and 70 % GPC, respectively. The GMs were carbonized in N2 environment at 800°C to produce carbon monoliths (CM00, CM10, CM30, CM50 and CM70). The CMs were CO2 activated at 800°C for 1 hour to produced activated carbon monolith electrodes (ACM00, ACM10, ACM30, ACM50 and ACM70). For each percentage of GPC, three duplicate symmetrical supercapacitor cells were fabricated using these activated carbon monolith electrodes respectively, and the capacitive performance amongst the cells was compared and analyzed in order to observe the relationship between the capacitive performance and the physical properties (microstructure and porosity) of the ACMs electrodes containing varying percentage of GPC.

  4. Diffusion and solubility of carbon in molybdenum and TZM

    International Nuclear Information System (INIS)

    The kinetics of decarburisation of molybdenum and TZM have been studied by quadrupole mass spectrometry over the temperature range 1260-20100 C. Flat and cylindrical samples were heated under a few 10-6 Torr 02. The outgassing flow of the carbon monoxide product as a function of time is controlled by the diffusion of carbon. Alloying with titanium and zirconium (TZM alloys) reduces the diffusion of carbon but increases its solubility below 17000C. The decarburisation is accompanied by internal oxidation which does not appear below 20000C in molybdenum. Anomalies in the diffusion of carbon can be attributed to the carbon becoming dissolved in the precipitated titanium oxide. (author)

  5. Fish as major carbonate mud producers and missing components of the tropical carbonate factory.

    Science.gov (United States)

    Perry, Chris T; Salter, Michael A; Harborne, Alastair R; Crowley, Stephen F; Jelks, Howard L; Wilson, Rod W

    2011-03-01

    Carbonate mud is a major constituent of recent marine carbonate sediments and of ancient limestones, which contain unique records of changes in ocean chemistry and climate shifts in the geological past. However, the origin of carbonate mud is controversial and often problematic to resolve. Here we show that tropical marine fish produce and excrete various forms of precipitated (nonskeletal) calcium carbonate from their guts ("low" and "high" Mg-calcite and aragonite), but that very fine-grained (mostly 4 mole % MgCO(3)) are their dominant excretory product. Crystallites from fish are morphologically diverse and species-specific, but all are unique relative to previously known biogenic and abiotic sources of carbonate within open marine systems. Using site specific fish biomass and carbonate excretion rate data we estimate that fish produce ∼6.1 × 10(6) kg CaCO(3)/year across the Bahamian archipelago, all as mud-grade (the < 63 μm fraction) carbonate and thus as a potential sediment constituent. Estimated contributions from fish to total carbonate mud production average ∼14% overall, and exceed 70% in specific habitats. Critically, we also document the widespread presence of these distinctive fish-derived carbonates in the finest sediment fractions from all habitat types in the Bahamas, demonstrating that these carbonates have direct relevance to contemporary carbonate sediment budgets. Fish thus represent a hitherto unrecognized but significant source of fine-grained carbonate sediment, the discovery of which has direct application to the conceptual ideas of how marine carbonate factories function both today and in the past. PMID:21368155

  6. Trading forest carbon - OSU

    Science.gov (United States)

    Issues associate with trading carbon sequestered in forests are discussed. Scientific uncertainties associated with carbon measurement are discussed with respect to proposed accounting procedures. Major issues include: (1) Establishing baselines. (2) Determining additivity from f...

  7. Potassium carbonate poisoning

    Science.gov (United States)

    Potassium carbonate is a white powder used to make soap, glass, and other items. This article discusses poisoning from swallowing or breathing in potassium carbonate. This article is for information only. Do ...

  8. Sodium carbonate poisoning

    Science.gov (United States)

    Sodium carbonate (known as washing soda or soda ash) is a chemical found in many household and ... products. This article focuses on poisoning due to sodium carbonate. This article is for information only. Do ...

  9. Biomass Carbon Stock

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — Biomass carbon includes carbon stored in above- and below-ground live plant components (such as leaf, branch, stem and root) as well as in standing and down dead...

  10. Carbon Monoxide Information Center

    Medline Plus

    Full Text Available ... Home / Safety Education / Safety Education Centers En Español Carbon Monoxide Information Center The Invisible Killer Carbon monoxide, also known as CO, is called the "Invisible ...

  11. Carbon Monoxide Safety

    Science.gov (United States)

    ... with the Media Fire Protection Technology Carbon monoxide safety outreach materials Help inform residents in your community ... KB | Spanish PDF 645 KB Handout: carbon monoxide safety Download this handout and add your organization's logo ...

  12. Soil Organic Carbon Stock

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — Soil organic carbon (SOC) is the carbon held within soil organic constituents (i.e., products produced as dead plants and animals decompose and the soil microbial...

  13. Carbon Monoxide Information Center

    Medline Plus

    Full Text Available ... Education / Safety Education Centers En Español Carbon Monoxide Information Center The Invisible Killer Carbon monoxide, also known ... Install one and check its batteries regularly. View Information About CO Alarms Other CO Topics Safety Tips ...

  14. Calcium carbonate overdose

    Science.gov (United States)

    Tums overdose; Calcium overdose ... Calcium carbonate can be dangerous in large amounts. ... Some products that contain calcium carbonate are certain: ... and mineral supplements Other products may also contain calcium ...

  15. Carbon nanotube nanoelectrode arrays

    Science.gov (United States)

    Ren, Zhifeng; Lin, Yuehe; Yantasee, Wassana; Liu, Guodong; Lu, Fang; Tu, Yi

    2008-11-18

    The present invention relates to microelectode arrays (MEAs), and more particularly to carbon nanotube nanoelectrode arrays (CNT-NEAs) for chemical and biological sensing, and methods of use. A nanoelectrode array includes a carbon nanotube material comprising an array of substantially linear carbon nanotubes each having a proximal end and a distal end, the proximal end of the carbon nanotubes are attached to a catalyst substrate material so as to form the array with a pre-determined site density, wherein the carbon nanotubes are aligned with respect to one another within the array; an electrically insulating layer on the surface of the carbon nanotube material, whereby the distal end of the carbon nanotubes extend beyond the electrically insulating layer; a second adhesive electrically insulating layer on the surface of the electrically insulating layer, whereby the distal end of the carbon nanotubes extend beyond the second adhesive electrically insulating layer; and a metal wire attached to the catalyst substrate material.

  16. 46 CFR 59.20-1 - Carbon-steel or alloy-steel castings.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 2 2010-10-01 2010-10-01 false Carbon-steel or alloy-steel castings. 59.20-1 Section 59... BOILERS, PRESSURE VESSELS AND APPURTENANCES Welding Repairs to Castings § 59.20-1 Carbon-steel or alloy-steel castings. Defects in carbon-steel or alloy-steel castings may be repaired by welding. The...

  17. 49 CFR 392.66 - Carbon monoxide; use of commercial motor vehicle when detected.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 5 2010-10-01 2010-10-01 false Carbon monoxide; use of commercial motor vehicle... SAFETY REGULATIONS DRIVING OF COMMERCIAL MOTOR VEHICLES Prohibited Practices § 392.66 Carbon monoxide... monoxide; (2) Where carbon monoxide has been detected in the interior of the commercial motor vehicle;...

  18. 46 CFR 147.65 - Carbon dioxide and halon fire extinguishing systems.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 5 2010-10-01 2010-10-01 false Carbon dioxide and halon fire extinguishing systems. 147... HAZARDOUS SHIPS' STORES Stowage and Other Special Requirements for Particular Materials § 147.65 Carbon dioxide and halon fire extinguishing systems. (a) Carbon dioxide or halon cylinders forming part of...

  19. Novel method for carbon nanofilament growth on carbon fibers

    Energy Technology Data Exchange (ETDEWEB)

    Phillips, Johathan [Los Alamos National Laboratory; Luhrs, Claudia [UNM MECH.ENG.; Terani, Mehran [UNM MECH.ENG.; Al - Haik, Marwan [UNM MECH.ENG.; Garcia, Daniel [UNM MECH.ENG.; Taha, Mahmoud R [UNM MECH.ENG.

    2009-01-01

    with smooth walls and low impurity content were grown. Carbon nanofibers were also grown on a carbon fiber cloth using plasma enhanced chemical vapor deposition (CVD) from a mixture of acetylene and ammonia. In this case, a cobalt colloid was used to achieve a good coverage of nanofibers on carbon fibers in the cloth. Caveats to CNT growth include damage in the carbon fiber surface due to high-temperatures (>800 C). More recently, Qu et al. reported a new method for uniform deposition of CNT on carbon fibers. However, this method requires processing at 1100 C in the presence of oxygen and such high temperature is anticipated to deepen the damage in the carbon fibers. In the present work, multi-scale filaments (herein, linear carbon structures with multi-micron diameter are called 'fibers', all structures with sub-micron diameter are called 'filaments') were created with a low temperature (ca. 550 C) alternative to CVD growth of CNTs. Specifically, nano-scale filaments were rapidly generated (> 10 microns/hour) on commercial micron scale fibers via catalytic (Pd particles) growth from a fuel rich combustion environment at atmospheric pressure. This atmospheric pressure process, derived from the process called Graphitic Growth by Design (GSD), is rapid, the maximum temperature low enough (below 700 C) to avoid structural damage and the process inexpensive and readily scalable. In some cases, a significant and unexpected aspect of the process was the generation of 'three scale' materials. That is, materials with these three size characteristics were produced: (1) micrometer scale commercial PAN fibers, (2) a layer of 'long' sub-micrometer diameter scale carbon filaments, and (3) a dense layer of 'short' nanometer diameter filaments.

  20. Metal filled porous carbon

    Science.gov (United States)

    Gross, Adam F.; Vajo, John J.; Cumberland, Robert W.; Liu, Ping; Salguero, Tina T.

    2011-03-22

    A porous carbon scaffold with a surface and pores, the porous carbon scaffold containing a primary metal and a secondary metal, where the primary metal is a metal that does not wet the surface of the pores of the carbon scaffold but wets the surface of the secondary metal, and the secondary metal is interspersed between the surface of the pores of the carbon scaffold and the primary metal.

  1. Effect of carbon nanofibers on the infiltration and thermal conductivity of carbon/carbon composites

    International Nuclear Information System (INIS)

    Highlights: → The CNFs improve the infiltration rate and thermal properties of carbon/carbon composites. → The densification rate increases with the CNF content increasing at the beginning of infiltration. → The values of the thermal conductivity of the composite obtain their maximum values at 5 wt.%. -- Abstract: Preforms containing 0, 5, 10, 15 and 20 wt.% carbon nanofibers (CNFs) were fabricated by spreading layers of carbon cloth, and infiltrated using the electrified preform heating chemical vapor infiltration method (ECVI) under atmospheric pressure. Initial thermal gradients were determined. Resistivity and density evolutions with infiltration time have been recorded. Scanning electron microscopy, polarized light micrograph and X-ray diffraction technique were used to analyze the experiment results. The results showed that the infiltration rate increased with the rising of CNF content, and after 120 h of infiltration, the density was the highest when the CNF content was 5 wt.%, but the composite could not be densified efficiently as the CNF content ranged from 10 wt.% to 20 wt.%. CNF-reinforced C/C composites have enhanced thermal conductivity, the values at 5 wt.% were increased by nearly 5.5-24.1% in the X-Y direction and 153.8-251.3% in the Z direction compared to those with no CNFs. When the additive content was increased to 20 wt.%, due to the holes and cavities in the CNF web and between carbon cloth and matrix, the thermal conductivities in the X-Y and Z directions decreased from their maximum values at 5 wt.%.

  2. 10 CFR 72.10 - Employee protection.

    Science.gov (United States)

    2010-01-01

    ... Form 3, “Notice to Employees,” referenced in 10 CFR 19.11(c). This form must be posted at locations..., HIGH-LEVEL RADIOACTIVE WASTE, AND REACTOR-RELATED GREATER THAN CLASS C WASTE General Provisions § 72.10... the index found on the home page. (f) No agreement affecting the compensation, terms, conditions,...

  3. Protolytic carbon film technology

    Energy Technology Data Exchange (ETDEWEB)

    Renschler, C.L.; White, C.A.

    1996-04-01

    This paper presents a technique for the deposition of polyacrylonitrile (PAN) on virtually any surface allowing carbon film formation with only the caveat that the substrate must withstand carbonization temperatures of at least 600 degrees centigrade. The influence of processing conditions upon the structure and properties of the carbonized film is discussed. Electrical conductivity, microstructure, and morphology control are also described.

  4. Carbon Goes To…

    Science.gov (United States)

    Savasci, Funda

    2014-01-01

    The purposes of this activity are to help middle school students understand the carbon cycle and realize how human activities affect the carbon cycle. This activity consists of two parts. The first part of the activity focuses on the carbon cycle, especially before the Industrial Revolution, while the second part of the activity focuses on how…

  5. Carbon/Carbon Pistons for Internal Combustion Engines

    Science.gov (United States)

    Taylor, A. H.

    1986-01-01

    Carbon/carbon piston performs same function as aluminum pistons in reciprocating internal combustion engines while reducing weight and increasing mechanical and thermal efficiencies of engine. Carbon/carbon piston concept features low piston-to-cylinder wall clearance - so low piston rings and skirts unnecessary. Advantages possible by negligible coefficient of thermal expansion of carbon/carbon.

  6. Carbon fiber content measurement in composite

    Science.gov (United States)

    Wang, Qiushi

    Malek methods. The activation energy (Ea) of the solid-state process is determined to be 202 kJ mol--1 in an oxidative atmosphere using Kissinger's method, which is 10-15 kJ mol--1 more than the results calculated in a nitrogen atmosphere. The value of the activation energy obtained using Ozawa-Flynn methods is in agreement with that using the Kissinger method. Different degradation mechanisms are used to compare with this value. Based on the analytical result, the actual thermal degradation mechanism of the CPPS is a Dn deceleration type. The carbonization temperature range of the CPPS is the same as pure PPS resin.

  7. Photoconductivity of Activated Carbon Fibers

    Science.gov (United States)

    Kuriyama, K.; Dresselhaus, M. S.

    1990-08-01

    The photoconductivity is measured on a high-surface-area disordered carbon material, namely activated carbon fibers, to investigate their electronic properties. Measurements of decay time, recombination kinetics and temperature dependence of the photoconductivity generally reflect the electronic properties of a material. The material studied in this paper is a highly disordered carbon derived from a phenolic precursor, having a huge specific surface area of 1000--2000m{sup 2}/g. Our preliminary thermopower measurements suggest that this carbon material is a p-type semiconductor with an amorphous-like microstructure. The intrinsic electrical conductivity, on the order of 20S/cm at room temperature, increases with increasing temperature in the range 30--290K. In contrast with the intrinsic conductivity, the photoconductivity in vacuum decreases with increasing temperature. The recombination kinetics changes from a monomolecular process at room temperature to a biomolecular process at low temperatures. The observed decay time of the photoconductivity is {approx equal}0.3sec. The magnitude of the photoconductive signal was reduced by a factor of ten when the sample was exposed to air. The intrinsic carrier density and the activation energy for conduction are estimated to be {approx equal}10{sup 21}/cm{sup 3} and {approx equal}20meV, respectively. The majority of the induced photocarriers and of the intrinsic carriers are trapped, resulting in the long decay time of the photoconductivity and the positive temperature dependence of the conductivity.

  8. Disintegration of Carbon Dioxide Molecules in a Microwave Plasma Torch

    Science.gov (United States)

    Kwak, Hyoung S.; Uhm, Han S.; Hong, Yong C.; Choi, Eun H.

    2015-12-01

    A pure carbon dioxide torch is generated by making use of 2.45 GHz microwave. Carbon dioxide gas becomes the working gas and produces a stable carbon dioxide torch. The torch volume is almost linearly proportional to the microwave power. Temperature of the torch flame is measured by making use of optical spectroscopy and thermocouple. Two distinctive regions are exhibited, a bright, whitish region of high-temperature zone and a bluish, dimmer region of relatively low-temperature zone. Study of carbon dioxide disintegration and gas temperature effects on the molecular fraction characteristics in the carbon dioxide plasma of a microwave plasma torch under atmospheric pressure is carried out. An analytical investigation of carbon dioxide disintegration indicates that substantial fraction of carbon dioxide molecules disintegrate and form other compounds in the torch. For example, the normalized particle densities at center of plasma are given by nCO2/nN = 6.12 × 10-3, nCO/nN = 0.13, nC/nN = 0.24, nO/nN = 0.61, nC2/nN = 8.32 × 10-7, nO2/nN = 5.39 × 10-5, where nCO2, nCO, nC, nO, nC2, and nO2 are carbon dioxide, carbon monoxide, carbon and oxygen atom, carbon and oxygen molecule densities, respectively. nN is the neutral particle density. Emission profiles of the oxygen and carbon atom radicals and the carbon monoxide molecules confirm the theoretical predictions of carbon dioxide disintegration in the torch.

  9. Carbon compound used in hydrogen storage

    International Nuclear Information System (INIS)

    In the present work it is studied the activated carbon of mineral origin for the sorption of hydrogen. The carbon decreased of particle size by means of the one alloyed mechanical. The time of mill was of 10 hours. The characterization one carries out by scanning electron microscopy and X-ray diffraction. The hydrogen sipped in the carbon material it was determined using the Thermal gravimetric method (TGA). The conditions of hydrogenation went at 10 atm of pressure and ambient temperature during 18 hours. They were also carried out absorption/desorption cycles of hydrogen in the same one system of thermal gravimetric analysis. The results showed percentages of sorption of 2% approximately in the cycles carried out in the system TGA and of 4.5% in weight of hydrogen at pressure of 10 atmospheres and ambient temperature during 18 hours. (Author)

  10. Carbon Sequestration Potential in Mangrove Wetlands of Southern of India

    Science.gov (United States)

    Chokkalingam, L.; Ponnambalam, K.; Ponnaiah, J. M.; Roy, P.; Sankar, S.

    2012-12-01

    Mangrove forest and the soil on which it grows are major sinks of atmospheric carbon. We present the results of a study on the carbon sequestration in the ground biomass of Avicennia marina including the organic carbon deposition, degradation and preservation in wetland sediments of Muthupet mangrove forest (southeast coast of India) in order to evaluate the influence of forests in the global carbon cycle. The inventory for estimating the ground biomass of Avicennia marina was carried out using random sampling technique (10 m × 10 m plot) with allometric regression equation. The carbon content in different vegetal parts (leaves, stem and root) of mangrove species and associated marshy vegetations was estimated using the combustion method. We observe that the organic carbon was higher (ca. 54.8%) recorded in the stems of Aegiceras corniculatum and Salicornia brachiata and lower (ca. 30.3%) in the Sesuvium portulacastrum leaves. The ground biomass and carbon sequestration of Avicennia marina are 58.56±12.65 t/ ha and 27.52±5.95 mg C/ha, respectively. The depth integrated organic carbon model profiles indicate an average accumulation rate of 149.75gC/m2.yr and an average remineralization rate of 32.89gC/m2.yr. We estimate an oxidation of ca. 21.85% of organic carbon and preservation of ca. 78.15% of organic carbon in the wetland sediments. Keywords: Above ground biomass, organic carbon, sequestration, mangrove, wetland sediments, Muthupet.

  11. Activated carbons and gold

    International Nuclear Information System (INIS)

    The literature on activated carbon is reviewed so as to provide a general background with respect to the effect of source material and activation procedure on carbon properties, the structure and chemical nature of the surface of the activated carbon, and the nature of absorption processes on carbon. The various theories on the absorption of gold and silver from cyanide solutions are then reviewed, followed by a discussion of processes for the recovery of gold and silver from cyanide solutions using activated carbon, including a comparison with zinc precipitation

  12. 40 CFR Table 10 to Part 455 - List of Appropriate Pollution Control Technologies

    Science.gov (United States)

    2010-07-01

    ...-aminopropane* (Fatty acids of coconut oil) 67301 Iminamide Activated Carbon. Alkyl* amino)-3-aminopropane *(53...*(fatty acids of coconut 67307 Iminamide Activated Carbon. Alkyl* dipropoxyamine *(47% C12, 18% C14, 10... coconut 67309 Iminamide Activated Carbon. Alkyl* amino)-3-aminopropane *(42%C12, 26%C18, 15%C14,...

  13. 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

  14. Carbon Stars in the Galactic Halo

    Science.gov (United States)

    Totten, E. J.; Irwin, M. J.

    1996-04-01

    A byproduct of the APM high redshift quasar survey (Irwin et al. 1991) was the discovery of ~ 20 distant (20-100kpc) cool AGB carbon stars (all N-type) at high Galactic latitude. In August we used the INT+IDS to survey the rest of the high latitude SGC sky visible from La Palma and found 10 more similar carbon stars. Before this work there were only a handful of published faint high latitude cool carbon stars known (eg. Margon et al., 1984, Mould et al., 1985) and there has been speculation as to their origin (eg. Sanduleak, 1980, van den Bergh & Lafontaine, 1984). Intermediate age carbon stars (3 -- 7 Gyrs) seem unlikely to have formed in the halo in isolation from other star forming regions so how did they get there ? One possiblity that we are investigating, is that they arise from either the disruption of tidally captured dSph galaxies or are a manifestion of the long sought after optical component of the Magellanic Stream. Lack of proper motion rules out the possibility of them being dwarf carbon stars (eg. Warren et al., 1992); indeed no N-type carbon stars have been found to be dwarf carbon stars. Our optical spectroscopy confirms their carbon star type (they are indistinguishable from cool AGB carbon stars in nearby dwarf galaxies) and hence probable large distances. We are extending our survey to the NGC region, obtaining radial velocities and good S:N fluxed spectra for all the carbon stars. This will enable us to investigate their kinematics, true spatial distribution and hence their origin. Even, in the event that these objects are somehow an integral part of the Galactic halo, then their velocities and large distances will enable direct studies of the velocity ellipsoid and rotation of the outer halo (eg. Green et al., 1994).

  15. Carbon isotope fluctuations in Precambrian carbonate sequences of several localities in Brazil

    Directory of Open Access Journals (Sweden)

    SIAL ALCIDES N.

    2000-01-01

    Full Text Available Carbon isotope fluctuations in Precambrian sedimentary carbonates between 2.8 Ga and 0.60 Ga in Brazil are examined in this study. The carbonate facies of the BIF of the 2.8 Ga-old Carajás Formation, state of Pará in northern Brazil, has rather homogeneous delta13C (-5 o/ooPDB, compatible with carbonatization of a silicate protolith by a CO2-rich fluid from mantle degassing. The Paleoproterozoic Gandarela Formation, state of Minas Gerais, displays a narrow delta13C variation (-1.5 to +0.5 o/oo compatible with carbon isotope signatures of carbonates deposited around 2.4 Ga worldwide. The Fecho do Funil Formation has probably recorded the Lomagundi delta13C positive anomaly (+6.4 to +7.1 o/ooPDB. The magnesite-bearing carbonates of the Orós mobile belt, state of Ceará, exhibit carbon isotope fluctuation within the range for carbonates deposited at 1.8 Ga. The C-isotope record of the Frecheirinha Formation, northwestern state of Ceará, shows negative delta13C values in its lower portion (-2 o/oo and positive values up section (+1 to +3 o/oo, which suggests this sequence is a cap carbonate deposited after a glacial event around 0.95 Ga. The Jacoca and Acauã sedimentary carbonate Formations, state of Sergipe, NE Brazil, show carbon isotope fluctuations very similar to each other (average around -5 o/oo, compatible with a deposition around 0.76 Ga. The younger Olho D'Água carbonate Formation, however, also in the state of Sergipe, displays negative delta13C values at the lower portion of the Formation, changing dramatically up section to positive values as high as +10 o/oo, a characteristic compatible with a Sturtian cap carbonate deposited around 0.69 Ga. On the light of the C isotope data discussed in this study, it seems that delta13C fluctuations in Paleoproterozoic carbonates in Brazil are within the range found globally for metasedimentary carbonates of this age. Carbon isotope data proved to be very useful in establishing relative

  16. Measuring radioactive carbon with a liquid scintillator

    Energy Technology Data Exchange (ETDEWEB)

    Petkov, T.

    1975-01-01

    Results are presented on the measurement of the soft beta emitter carbon-14 in a liquid scintillator by means of a single-channel scintillation spectrometer provided with a lucite light-guide. The scintillation solution had the composition: PPO-10 grams, POPOP-0.25 grams, naphthalene-100 grams, and dioxane-1 liter. The background count rate and counting efficiency were determined at a discrimination threshold of 2 V and an amplification of 54. Carbon-14 activities of 10 to 20 picocuries could be measured at 90% counting efficiency under the proper conditions. (SJR)

  17. Soil carbon stocks in Sarawak, Malaysia

    Energy Technology Data Exchange (ETDEWEB)

    Padmanabhan, E., E-mail: Eswaran_padmanabhan@petronas.com.my [Department of Geosciences, Faculty of Geosciences and Petroleum Engineering, Universiti Teknologi PETRONAS, Tronoh, 31750, Perak (Malaysia); Eswaran, H.; Reich, P.F. [USDA-Natural Resources Conservation Service, Washington, DC 20250 (United States)

    2013-11-01

    The relationship between greenhouse gas emission and climate change has led to research to identify and manage the natural sources and sinks of the gases. CO{sub 2}, CH{sub 4}, and N{sub 2}O have an anthropic source and of these CO{sub 2} is the least effective in trapping long wave radiation. Soil carbon sequestration can best be described as a process of removing carbon dioxide from the atmosphere and relocating into soils in a form that is not readily released back into the atmosphere. The purpose of this study is to estimate carbon stocks available under current conditions in Sarawak, Malaysia. SOC estimates are made for a standard depth of 100 cm unless the soil by definition is less than this depth, as in the case of lithic subgroups. Among the mineral soils, Inceptisols tend to generally have the highest carbon contents (about 25 kg m{sup −2} m{sup −1}), while Oxisols and Ultisols rate second (about 10–15 kg m{sup −2} m{sup −1}). The Oxisols store a good amount of carbon because of an appreciable time-frame to sequester carbon and possibly lower decomposition rates for the organic carbon that is found at 1 m depths. Wet soils such as peatlands tend to store significant amounts of carbon. The highest values estimated for such soils are about 114 kg m{sup −2} m{sup −1}. Such appreciable amounts can also be found in the Aquepts. In conclusion, it is pertinent to recognize that degradation of the carbon pool, just like desertification, is a real process and that this irreversible process must be addressed immediately. Therefore, appropriate soil management practices should be instituted to sequester large masses of soil carbon on an annual basis. This knowledge can be used effectively to formulate strategies to prevent forest fires and clearing: two processes that can quickly release sequestered carbon to the atmosphere in an almost irreversible manner. - Highlights: • Soil carbon stocks in different soils in Sarawak • In depth discussion of

  18. Graphene: carbon in two dimensions

    Directory of Open Access Journals (Sweden)

    Mikhail I. Katsnelson

    2007-01-01

    Full Text Available Carbon is one of the most intriguing elements in the Periodic Table. It forms many allotropes, some known from ancient times (diamond and graphite and some discovered 10-20 years ago (fullerenes and nanotubes. Interestingly, the two-dimensional form (graphene was only obtained very recently, immediately attracting a great deal of attention. Electrons in graphene, obeying a linear dispersion relation, behave like massless relativistic particles. This results in the observation of a number of very peculiar electronic properties – from an anomalous quantum Hall effect to the absence of localization – in this, the first two-dimensional material. It also provides a bridge between condensed matter physics and quantum electrodynamics, and opens new perspectives for carbon-based electronics.

  19. TOP 10 NATIONAL EVENTS

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    1 Development Goals Defined China’s 12th Five-Year Plan for National Economic and Social Development (2011-15) was approved by the National People’s Congress, the country’s top legislature, on March 14. Focusing on building a green economy, China plans to cut energy consumption and carbon dioxide

  20. Preparation and study of ultra-low density carbon aerogel

    International Nuclear Information System (INIS)

    The ultra-low density resorcinol (R)-formaldehyde (F) aerogel and carbon aerogel were prepared via a sol-gel route, which density are 10 mg/cm3 and 20 mg/cm3, respectively. The microstructures and properties of the carbon aerogel were investigated by using scanning electron microscope, transmission electron microscope, pore size distribution measurement, and so on. The ultra-low density products are some tortuous chains consisting of carbon nanospheres ranging from 10 to 15 nm. The carbon nanosphere consists of nanoparticles whose sizes are about several nanometers. The surface area of the low-density carbon aerogel is 1 783.7 m2/g. The hydrogen adsorption capacity of the ultra-low density carbon aerogel is 4.4% (mass fraction) at liquid nitrogen temperature under atmospheric pressure. (authors)

  1. Effects of carbon dioxide on Penicillium chrysogenum: an autoradiographic study

    International Nuclear Information System (INIS)

    Previous research has shown that dissolved carbon dioxide causes significant changes in submerged penicillin fermentations, such as stunted, swollen hyphae, increased branching, lower growth rates, and lower penicillin productivity. Influent carbon dioxide levels of 5 and 10% were shown through the use of autoradiography to cause an increase in chitin synthesis in submerged cultures of Penicillium chrysogenum. At an influent 5% carbon dioxide level, chitin synthesis is ca. 100% greater in the subapical region of P. chrysogenum hyphae than that of the control, in which there was no influent carbon dioxide. Influent carbon dioxide of 10% caused an increase of 200% in chitin synthesis. It is believed that the cell wall must be plasticized before branching can occur and that high amounts of dissolved carbon dioxide cause the cell to lose control of the plasticizing effect, thus the severe morphological changes occur

  2. Carbonated aqueous media for quench heat treatment of steels

    Science.gov (United States)

    Nayak, U. Vignesh; Rao, K. M. Pranesh; Pai, M. Ashwin; Prabhu, K. Narayan

    2016-07-01

    Distilled water and polyalkylene glycol (PAG)-based aqueous quenchants of 5 and 10 vol.% with and without carbonation were prepared and used as heat transfer media during immersion quenching. Cooling curves were recorded during quenching of an inconel 600 cylindrical probe instrumented with multiple thermocouples. It was observed that the vapor stage duration was prolonged and the wetting front ascended uniformly for quenching with carbonated media. The cooling data were analyzed by determining the critical cooling parameters and by estimating the spatially dependent probe/quenchant interfacial heat flux transients. The study showed significantly reduced values of heat transfer rate for carbonated quenchants compared to quenchants without carbonation. Further, the reduction was more pronounced in the case of PAG-based carbonated quenchants than carbonated distilled water. The results also showed the dependence of heat transfer characteristics of the carbonated media on polymer concentration. The effect of quench uniformity on the microstructure of the material was assessed.

  3. Low Cost Carbon Fiber From Renewable Resources

    International Nuclear Information System (INIS)

    The Department of Energy Partnership for a New Generation of Vehicles has shown that, by lowering overall weight, the use of carbon fiber composites could dramatically decrease domestic vehicle fuel consumption. For the automotive industry to benefit from carbon fiber technology, fiber production will need to be substantially increased and fiber price decreased to$7/kg. To achieve this cost objective, alternate precursors to pitch and polyacrylonitrile (PAN) are being investigated as possible carbon fiber feedstocks. Additionally, sufficient fiber to provide 10 to 100 kg for each of the 13 million cars and light trucks produced annually in the U.S. will require an increase of 5 to 50-fold in worldwide carbon fiber production. High-volume, renewable or recycled materials, including lignin, cellulosic fibers, routinely recycled petrochemical fibers, and blends of these components, appear attractive because the cost of these materials is inherently both low and insensitive to changes in petroleum price. Current studies have shown that a number of recycled and renewable polymers can be incorporated into melt-spun fibers attractive as carbon fiber feedstocks. Highly extrudable lignin blends have attractive yields and can be readily carbonized and graphitized. Examination of the physical structure and properties of carbonized and graphitized fibers indicates the feasibility of use in transportation composite applications

  4. Conductive Carbon Coatings for Electrode Materials

    International Nuclear Information System (INIS)

    A simple method for optimizing the carbon coatings on non-conductive battery cathode material powders has been developed at Lawrence Berkeley National Laboratory. The enhancement of the electronic conductivity of carbon coating enables minimization of the amount of carbon in the composites, allowing improvements in battery rate capability without compromising energy density. The invention is applicable to LiFePO4 and other cathode materials used in lithium ion or lithium metal batteries for high power applications such as power tools and hybrid or plug-in hybrid electric vehicles. The market for lithium ion batteries in consumer applications is currently $5 billion/year. Additionally, lithium ion battery sales for vehicular applications are projected to capture 5% of the hybrid and electric vehicle market by 2010, and 36% by 2015 (http://www.greencarcongress.com). LiFePO4 suffers from low intrinsic rate capability, which has been ascribed to the low electronic conductivity (10-9 S cm-1). One of the most promising approaches to overcome this problem is the addition of conductive carbon. Co-synthesis methods are generally the most practical route for carbon coating particles. At the relatively low temperatures (4, however, only poorly conductive disordered carbons are produced from organic precursors. Thus, the carbon content has to be high to produce the desired enhancement in rate capability, which decreases the cathode energy density

  5. Ab initio simulation of helium inside carbon nanotubes

    International Nuclear Information System (INIS)

    In present work we consider the complex behaviour of quantum liquids like liquid He-4 inside carbon nanotubes. Interactions between helium atoms and carbon atoms of the short-length atomistic model and model with periodical boundary conditions of carbon nanotube were studied via ab initio quantum simulations. Effects of geometrical confinement of the tube on the He behaviour inside CNT (13,0) have been explored. Nanotubes with typical average diameter of 10 angstroms are under consideration.

  6. Standardisation of gas mixtures for estimating carbon monoxide transfer factor.

    OpenAIRE

    Kendrick, A. H.; Laszlo, G.

    1993-01-01

    BACKGROUND--The American Thoracic Society recommends that the inspired concentration used for the estimation of carbon monoxide transfer factor (TLCO) mixture should be 0.25-0.35% carbon monoxide, 10-14% helium, 17-21% oxygen, balance nitrogen. Inspired oxygen influences alveolar oxygen and hence carbon monoxide uptake, such that transfer factor increases by 0.35% per mm Hg decrease in alveolar oxygen. To aid in the standardisation of TLCO either a known inspired oxygen concentration should b...

  7. Highly effective metal vapor absorbents based on carbon nanotubes

    Science.gov (United States)

    Liu, Zongwen; Gao, Yihua; Bando, Yoshio

    2002-12-01

    It was shown that, when filled with gallium, carbon nanotubes can absorb copper vapor with extraordinarily high efficiency. The copper vapor generated from the supporting copper grid upon heating to 800 °C in an electron microscope under a pressure of 1.0×10-5 Pa quickly deposited into the carbon nanotubes and formed an alloy with gallium where the vapor pressure is up to 500 times higher (5×10-3 Pa). These filled carbon nanotubes may be used as highly sensitive toxic or radioactive metal vapor absorbents since gallium also tends to form alloys with metals like mercury and uranium.

  8. Production process for boron carbide coated carbon material and boron carbide coated carbon material obtained by the production process

    International Nuclear Information System (INIS)

    A boron carbide coated carbon material is used for a plasma facing material of a thermonuclear reactor. The surface of a carbon material is chemically reacted with boron oxide to convert it into boron carbide. Then, it is subjected to heat treatment at a temperature of not lower than 1600degC in highly evacuated or inactive atmosphere to attain a boron carbide coated carbon material. The carbon material used is an artificial graphite or a carbon fiber reinforced carbon composite material. In the heat treatment, when the atmosphere is in vacuum, it is highly evacuated to less than 10Pa. Alternatively, in a case of inactive atmosphere, argon or helium gas each having oxygen and nitrogen content of not more than 20ppm is used. With such procedures, there can be obtained a boron carbide-coated carbon material with low content of oxygen and nitrogen impurities contained in the boron carbide coating membrane thereby hardly releasing gases. (I.N.)

  9. Dissolved inorganic carbon, total alkalinity, pH, and other variables collected from profile and discrete observations using CTD, Niskin bottle, and other instruments from R/V Okeanos Explorer, off the east coast of Florida, United States from 2014-05-10 to 2014-05-17 (NCEI Accession 0131424)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This archival package contains carbon and nutrient related data that were collected from CTD profile measurements off the east coast of Florida, United States...

  10. The influence of a secondary heat treatment on mechanical and oxidation properties of unidirectional carbon/carbon and carbon/furfural-siloxane composites

    Czech Academy of Sciences Publication Activity Database

    Glogar, Petr; Fott, Pavel; Manocha, L.; Patel, A.

    Singapore : World Scientific, 1996 - (Palmer, K.; Marx , D.; Wright, M.), s. 380-392 ISBN 981-02-2801-5. [Carbon and Carbonaceous Composite Materials: Structure-Property Relationships. Malenovice (CZ), 10.10.1995-13.10.1995] R&D Projects: GA AV ČR IAA246405

  11. Carbon storage and recycling in short-rotation energy crops

    International Nuclear Information System (INIS)

    Short-rotation energy crops can play a significant role in storing carbon compared to the agricultural land uses they would displace. However, the benefits from these plantations in avoiding further use of fossil fuels and in taking pressure off native forests for energy uses provides longer term carbon benefits than the plantation carbon sequestration itself. The fast growth and harvest frequency of plantations tends to limit the amount of above- and below-ground carbon storage in them. The primary components of plantation carbon sequestering compared to sustained agricultural practices involve above ground wood, possible increased soil carbon, litter layer formation, and increased root biomass. On the average, short-rotation plantations in total may increase carbon inventories by about 10 to 40 tonnes per hectare over about a 20 to 50 year period when displacing cropland. This is about doubling in storage over cropland and about one-half the storage in human-impacted forests. The sequestration benefit of wood energy crops over cropland would be negated in about 75 to 100 years by the use of fossil fuels to tend the plantations and handle biomass. Plantation interactions with other land uses and total landscape carbon inventory is important in assessing the relative role plantations play in terestrial and atmospheric carbon dynamics. It is speculated that plantations, when viewed in this context, could generate a global levelling of net carbon emissions for approximately 10 to 20 years. 16 refs., 7 figs

  12. Investigation of Carbon incorporation into Al 6061 alloys

    Science.gov (United States)

    Ge, Xiaoxiao; Riba, Lourdes Salamanca; Wuttig, Manfred; Covetics Collaboration

    The incorporation of carbon nanostructures into aluminum alloys, such as Al6061 and Al7075, has the potential to further improve the mechanical, electrical and anti-corrosion properties of these alloys. We report on a novel method to incorporate up to 10.0 wt% carbon into the crystal structure of Al 6061 alloys to form a new material ``Al Covetics''. In this method, a DC current is applied to molten Al metal containing activated carbon particles. The current facilitates ionization of the carbon atoms and their bonding to each other, forming graphic chains and layers along preferential directions of the Al lattice. Raman mapping of the G and D peaks of graphitic carbon was used to confirm the role of the current in ensuring that the carbons remain in the metal by electro-static force and spread into the metal matrix evenly. Sp2 bonding of carbon was found all over the surface in the Covetics. Carbon signals were also observed everywhere in Covetics with Energy Dispersive X-ray Spectroscopy. However, localized carbon signals were detected in samples made with activated carbon but without applying any current. The dependence of the mechanical, electrical and structural properties of Al Covetics on C content from 3 to 10 wt. % will be presented.

  13. Plumbing carbon nanotubes

    Science.gov (United States)

    Jin, Chuanhong; Suenaga, Kazu; Iijima, Sumio

    2008-01-01

    Since their discovery, the possibility of connecting carbon nanotubes together like water pipes has been an intriguing prospect for these hollow nanostructures. The serial joining of carbon nanotubes in a controlled manner offers a promising approach for the bottom-up engineering of nanotube structures-from simply increasing their aspect ratio to making integrated carbon nanotube devices. To date, however, there have been few reports of the joining of two different carbon nanotubes. Here we demonstrate that a Joule heating process, and associated electro-migration effects, can be used to connect two carbon nanotubes that have the same (or similar) diameters. More generally, with the assistance of a tungsten metal particle, this technique can be used to seamlessly join any two carbon nanotubes-regardless of their diameters-to form new nanotube structures.

  14. Carbon-negative biofuels

    International Nuclear Information System (INIS)

    Current Kyoto-based approaches to reducing the earth's greenhouse gas problem involve looking for ways to reduce emissions. But these are palliative at best, and at worst will allow the problem to get out of hand. It is only through sequestration of atmospheric carbon that the problem can be solved. Carbon-negative biofuels represent the first potentially huge assault on the problem, in ways that are already technically feasible and practicable. The key to carbon negativity is to see it not as technically determined but as an issue of strategic choice, whereby farmers and fuel producers can decide how much carbon to return to the soil. Biochar amendment to the soil not only sequesters carbon but also enhances the fertility and vitality of the soil. The time is approaching when biofuels will be carbon negative by definition, and, as such, they will sweep away existing debates over their contribution to the solution of global warming. (author)

  15. INVESTIGATIONS ON VINYLENE CARBONATE Ⅰ. PREPARATION AND PROPERTIES OF POLY-(VINYLENE CARBONATE)

    Institute of Scientific and Technical Information of China (English)

    HUANG Jiaxian; CHEN Guohua; EDDY TIJSMA; LEEN VAN DER DOES; ADRIAAN BANTJES

    1990-01-01

    Bulk polymerization of vinylene carbonate using t- butylperoxypivalate at 40 ℃ gave colourless,high molecular weight poly(vinylene carbonate) (PVCA). Solutions of PVCA in acetone and DMF are not stable at 25 ℃ and this degradation was studied. From measurements in DMF with unfractionated PVCA a Mark-Houwink equation was obtained:[η] (dl g-1)=1.63×10-4 -MW0.736

  16. Respiration and assimilation processes reflected in the carbon isotopic composition of atmospheric carbon dioxide

    International Nuclear Information System (INIS)

    The paper presents diurnal variations of concentration and carbon isotopic composition of atmospheric carbon dioxide caused by respiration and assimilation processes. Air samples were collected during early and late summer in 1998 in unpolluted area (village Guciow located near Roztocze National Park, SE Poland) in three different environments: uncultivated field on a hill, a meadow in the Wieprz river valley and a forest. The effect is very strong during intensive vegetation growth on a sunny day and clear night. The largest diurnal variations in atmospheric CO2 concentration and its carbon isotopic composition in June above the meadow were about 480 ppm and 10 pro mille, respectively. (author)

  17. The Ammount of Interstellar Carbon Locked in Solid Hydrogenated Amorphous Carbon

    OpenAIRE

    Furton, D. G.; Laiho, J. W.; Witt, A. N.

    1999-01-01

    We review the literature and present new experimental data to determine the amount of carbon likely to be locked in form of solid hydrogenated amorphous carbon (HAC) grains. We conclude on the basis of a thorough analysis of the intrinsic strength of the C-H stretching band at 3.4 micron that between 10 and 80 ppM H of carbon is in the form of HAC grains. We show that it is necessary to know the level of hydrogenation (H/C) of the interstellar HAC to determine more precisely the amount of car...

  18. Fabrication of carbon nanorod from the irradiation of proton beam on carbon nanotube and characterization of its resistance variation

    International Nuclear Information System (INIS)

    Fabrication method of the transparent carbon nanotubes film on the glass with the transparency of 50 ∼ 80 % and the sheet resistance of 500 ∼ 2000 Ω/sq is developed based on the established study of the enhancement of the conductivity. Deformation of the bundle-type single-walled carbon nanotubes are analyzed with the variation of the energy transfer in the carbon nanotubes by the variation of the dose of the 10 MeV proton beam. Construction of the variation of the conductivity of the carbon nanotube network and the variation of the transparency of the glass are used for the feasibility of the fabrication of the transparent electrode using carbon nanotubes network. Transparent carbon nanotubes film are fabricated using spray method and the sheet resistance and transparency are controlled by the control of the quantity of the dispersion. Accumulated energy on the carbon nanotubes are controlled by the dose of the 10 MeV proton. Proton irradiation creates defects on the carbon nanotubes by particle collision and the recombination of the defects generates the decrease of the diameter of the carbon nanotubes. Ejection of the carbon from the carbon nanotubes generates not only the formation of the connection between carbon nanotubes but also between carbon nanotube bundles. These connections decrease the resistance between carbon nanotube networks and 2.5 times increase is measured. Although the electrical conductivity is increased by the proton irradiation, sulfuration of the glass is increased. Variation of the transparency is caused by the positive ion irradiation and the transparency is decreased with the dose due to the increase of the energy transfer on the glass

  19. Carbon monoxide poisoning

    OpenAIRE

    Dolan, Michael C.

    1985-01-01

    Carbon monoxide poisoning is a significant cause of illness and death. Its protean symptoms probably lead to a gross underestimation of its true incidence. Low levels of carbon monoxide aggravate chronic cardiopulmonary problems, and high levels are associated with cardiac arrhythmias and cerebral edema. Patients who survive acute poisoning are at risk of delayed neurologic sequelae. The measurement of carboxyhemoglobin levels does not reveal the tissue levels of carbon monoxide but is useful...

  20. The carbon dioxide cycle

    Science.gov (United States)

    James, P.B.; Hansen, G.B.; Titus, T.N.

    2005-01-01

    The seasonal CO2 cycle on Mars refers to the exchange of carbon dioxide between dry ice in the seasonal polar caps and gaseous carbon dioxide in the atmosphere. This review focuses on breakthroughs in understanding the process involving seasonal carbon dioxide phase changes that have occurred as a result of observations by Mars Global Surveyor. ?? 2004 COSPAR. Published by Elsevier Ltd. All rights reserved.

  1. Carbon monoxide poisoning (acute)

    OpenAIRE

    Olson, Kent; Smollin, Craig

    2010-01-01

    The main symptoms of carbon monoxide poisoning are non-specific in nature and relate to effects on the brain and heart. The symptoms correlate poorly with serum carboxyhaemoglobin levels. People with comorbidity, elderly or very young people, and pregnant women are most susceptible.Carbon monoxide is produced by the incomplete combustion of carbon fuels, including inadequately ventilated heaters and car exhausts, or from chemicals such as methylene chloride paint stripper.Poisoning is cons...

  2. Carbon nanotubes decorating methods

    OpenAIRE

    A.D. Dobrzańska-Danikiewicz; D. Łukowiec; D. Cichock; W. Wolany

    2013-01-01

    Purpose: The work is to present and characterise various methods of depositing carbon nanotubes with nanoparticles of precious metals, and also to present the results of own works concerning carbon nanotubes coated with platinum nanoparticles.Design/methodology/approach: Electron transmission and scanning microscopy has been used for imaging the structure and morphology of the nanocomposites obtained and the distribution of nanoparticles on the surface of carbon nanotubes.Findings: The studie...

  3. Functionalization of Carbon Nanotubes

    OpenAIRE

    Abraham, Jürgen

    2005-01-01

    Carbon nanotubes have an enormous potential due to their outstanding electronic, optical, and mechanical properties. However, any technological application is still hindered due to problems regarding the processibility of the pristine carbon nanotubes. In the past few years, it has been shown that the chemical modification of the carbon nanotubes is an inevitable step prior to their application. The first part of this work (chapter 3.1) was focused on the purification of pristine laser ablati...

  4. Improvement in char formability of phenolic resin for development of Carbon/Carbon composites

    International Nuclear Information System (INIS)

    In the processing of carbon/carbon composites using polymer resin as the matrix precursor, it is inevitable that a porous structure was formed after carbonization. As a result, densification by liquid phase impregnation followed by recarbonization is required to obtain a densified composite. Consequently, the char formability of resin is an important factor in reducing the number of densification cycles and hence the processing cost. In this study, a novel approach is adopted to improve the densification of carbon/carbon composites by using a new phenolic resin modified by pitch. For this purpose, soluble part of pitch was extracted and dispersed in resol type phenolic resin. The polymerization reaction was performed in presence of para-formaldehyde and a resol-pitch compound was obtained. The second compound was prepared by mixing novolac-furfural in 55:45 weight ratio containing 9% by weight hexamethylene tetramine. This compound was added to resol-pitch compound in 10,20,50 and 80 w %. The microstructure of carbonized resin was investigated by X-ray diffraction and char yield, and the linear and volumetric shrinkage were obtained. Results show that in 80:20 ratio of resol-pitch to novolac-furfural , the char yield would be maximized by 71% and volumetric shrinkage would be minimized at 16.4%. At the same time, XRD results indicate that the resin has a strong ability to graphitize carbon/carbon composites matrix as a necessary step for its processing

  5. Preparation of carbon/carbon composite by pyrolysis of ethanol and methane

    International Nuclear Information System (INIS)

    Highlights: • The mixture of ethanol and methane was used as the precursor of pyrolytic carbon. • C/C composites with high textured pyrolytic carbon and high density were obtained. • At the same condition, the high textured carbon cannot be obtained using methane. • The mixture precursor is a promising candidate for C/C composites in CVI. - Abstract: A high textured carbon/carbon (C/C) composite was prepared using the mixture gas of ethanol and methane as the precursor by isothermal chemical vapor infiltration. The preform was infiltrated at 1180 °C with the gas pressure from 2 to 10 kPa. For 85 h infiltration, the average bulk density is up to 1.8 ± 0.02 g cm−3. The texture of the infiltrated carbon was studied by polarized-light microscopy and characterized with the aid of the extinction angle. Texture and fracture morphology of the pyrolytic carbon matrix were observed using scanning electronic microscope. C/C composites with high textured pyrolytic carbon matrix and high density were obtained by pyrolysis of ethanol and methane. This indicates the mixture of ethanol and methane is a promising candidate of the precursors for the preparation of C/C composites

  6. The Reionisation of Carbon

    CERN Document Server

    Finlator, K; Huang, S; Davé, R; Zackrisson, E; Oppenheimer, B D

    2014-01-01

    Observations suggest that CII was more abundant than CIV in the intergalactic medium towards the end of the hydrogen reionisation epoch. This transition provides a unique opportunity to study the enrichment history of intergalactic gas and the growth of the ionising background (UVB) at early times. We study how carbon absorption evolves from z=10-5 using a cosmological hydrodynamic simulation that includes a self-consistent multifrequency UVB as well as a well-constrained model for galactic outflows to disperse metals. Our predicted UVB is within 2-4 times that of Haardt & Madau (2012), which is fair agreement given the uncertainties. Nonetheless, we use a calibration in post-processing to account for Lyman-alpha forest measurements while preserving the predicted spectral slope and inhomogeneity. The UVB fluctuates spatially in such a way that it always exceeds the volume average in regions where metals are found. This implies both that a spatially-uniform UVB is a poor approximation and that metal absorp...

  7. Physics of carbon nanostructures

    International Nuclear Information System (INIS)

    Carbon is a prominent element that appears in various structures with new promising technological applications. The physics of carbon nanostructures is one of the hot topics in modern condensed matter theory. I plan to present a brief introduction into the theory of variously shaped carbon nanostructures paying special attention to generic field-theory models. The preliminary plan is the following: (1) a brief historical excursus, (2) the most interesting experimental observations, (3) generic models for the description of electronic states in carbon nanoparticles (Dirac-type equations, defects, geometry, etc.), (4) open problems. (author)

  8. Carbon Trading. Literature Overview

    International Nuclear Information System (INIS)

    From Pigou and Coase to the Kyoto Protocol, carbon trading has resulted in pricing of the negative externalities emanating from pollution. This report highlights leading literature and empirical findings on carbon trading, amongst others addressing the relevant carbon and related markets, the (lack of) success of carbon trading so far and room for improvement as well as its impact on investments in emission reduction. This report is part of a set of SEO-reports on finance and sustainability. The other reports deal with: Financing the Transition to Sustainable Energy; Innovations in financing environmental and social sustainability; and Sustainable investment.

  9. Nanoindentation of Carbon Nanostructures.

    Science.gov (United States)

    Kumar, Dinesh; Singh, Karamjit; Verma, Veena; Bhatti, H S

    2016-06-01

    In the present research paper carbon nanostructures viz. single walled carbon nanotubes, multi-walled carbon nanotubes, single walled carbon nanohorns and graphene nanoplatelets have been synthesized by CVD technique, hydrothermal method, DC arc discharge method in liquid nitrogen and microwave technique respectively. After synthesis 5 mm thick pallets of given nanomaterial are prepared by making a paste in isopropyl alcohol and using polyvinylidene difluoride as a binder and then these pallets were used for nanoindentation measurements. Hardness, reduced modulus, stiffness, contact height and contact area have been measured using nanoindenter. PMID:27427726

  10. Global Carbon Cycle

    OpenAIRE

    Probst, Jean-Luc; Faure, Hugues; Veizer, Jan

    1999-01-01

    The European Union of Geosciences held its 9th biannual meeting in Strasbourg, March 23–27, 1997. During this meeting, Symposium N8 18, Global carbon Cycle, was held under the sponsorship of the IGCP 1 n8404 on the «Terrestrial Carbon in the past 125 Ka», the INQUA 2 Carbon Commission and the ESCOBA-Biosphere 3 project of the EC Environment and Climate Programme. The «Global Carbon Cycle» Symposium attracted 28 oral and poster presentations and about one hundred par...

  11. Changing global carbon cycle

    International Nuclear Information System (INIS)

    Full text: The increase in atmospheric carbon dioxide (C02) is the single largest human perturbation on the earth's radiative balance contributing to climate change. Its rate of change reflects the balance between anthropogenic carbon emissions and the dynamics of a number of terrestrial and ocean processes that remove or emit C02. It is the long term evolution of this balance that will determine to large extent the speed and magnitude of the human induced climate change and the mitigation requirements to stabilise atmospheric C02 concentrations at any given level. In this talk, we show new trends in global carbon sources and sinks, with particularly focus on major shifts occurring since 2000 when the growth rate of atmospheric C02 has reached its highest level on record. The acceleration in the C02 growth results from the combination of several changes in properties of the carbon cycle, including: acceleration of anthropogenic carbon emissions; increased carbon intensity of the global economy, and decreased efficiency of natural carbon sinks. We discuss in more detail some of the possible causes of the reduced efficiency of natural carbon sinks on land and oceans, such as the decreased net sink in the Southern Ocean and on terrestrial mid-latitudes due to world-wide occurrence of drought. All these changes reported here characterise a carbon cycle that is generating stronger than expected climate forcing, and sooner than expected

  12. Mariner 10 Image Archive

    Data.gov (United States)

    National Aeronautics and Space Administration — The Mariner 10 Image Archive includes tools to view shaded relief maps of the surface of Mercury, a 3D globe, and all images acquired by NASA's Mariner 10 mission.

  13. Heavy duty piezoresistivity induced strain sensing natural rubber/carbon black nanocomposites reinforced with different carbon nanofillers

    Science.gov (United States)

    He, Qingliang; Yuan, Tingting; Zhang, Xi; Guo, Shimei; Liu, Jingjing; Liu, Jiurong; Liu, Xinyu; Sun, Luyi; Wei, Suying; Guo, Zhanhu

    2014-09-01

    Durable piezoresistive effects of natural rubber nanocomposites have been demonstrated, i.e., with stable and reversible electrical resistance change within the tested 3000 cycles upon applying a small compressive strain (˜16.7%) under a relatively high frequency (0.5 Hz, 2 s/cycle). This unique function was achieved for the first time by combining carbon nanotubes and carbon nanofibers with natural rubber composites pretreated with carbon black. Even though the combination of different carbon nanomaterials, such as graphene nanosheets and carbon nanotubes, can improve the dispersion quality of both the nanostructures in solution or in polymer matrices, this type of synergistic effect between carbon nanotubes and carbon nanofibers in producing stable and reversible piezoresistive effect has been rarely reported. Besides, the strong reinforcement (compressive stress at a maximum strain of 16.7% was increased from 12.6 for untreated to 18.5 MPa for the natural rubber/carbon black composites treated with a combination of 1.0 wt% carbon nanotubes and 1.0 wt% carbon nanofibers) makes the as-prepared composites promising for heavy duty pressure sensors, i.e., healthy motion monitoring of industrial machinery vibrations.

  14. Carbon Nanotube Bolometer for Absolute FTIR Spectroscopy

    Science.gov (United States)

    Woods, Solomon; Neira, Jorge; Tomlin, Nathan; Lehman, John

    We have developed and calibrated planar electrical-substitution bolometers which employ absorbers made from vertically-aligned carbon nanotube arrays. The nearly complete absorption of light by the carbon nanotubes from the visible range to the far-infrared can be exploited to enable a device with read-out in native units equivalent to optical power. Operated at cryogenic temperatures near 4 K, these infrared detectors are designed to have time constant near 10 ms and a noise floor of about 10 pW. Built upon a micro-machined silicon platform, each device has an integrated heater and thermometer, either a carbon nanotube thermistor or superconducting transition edge sensor, for temperature control. We are optimizing temperature-controlled measurement techniques to enable high resolution spectral calibrations using these devices with a Fourier-transform spectrometer.

  15. Drought sensitivity of Amazonian carbon balance revealed by atmospheric measurements.

    Science.gov (United States)

    Gatti, L V; Gloor, M; Miller, J B; Doughty, C E; Malhi, Y; Domingues, L G; Basso, L S; Martinewski, A; Correia, C S C; Borges, V F; Freitas, S; Braz, R; Anderson, L O; Rocha, H; Grace, J; Phillips, O L; Lloyd, J

    2014-02-01

    Feedbacks between land carbon pools and climate provide one of the largest sources of uncertainty in our predictions of global climate. Estimates of the sensitivity of the terrestrial carbon budget to climate anomalies in the tropics and the identification of the mechanisms responsible for feedback effects remain uncertain. The Amazon basin stores a vast amount of carbon, and has experienced increasingly higher temperatures and more frequent floods and droughts over the past two decades. Here we report seasonal and annual carbon balances across the Amazon basin, based on carbon dioxide and carbon monoxide measurements for the anomalously dry and wet years 2010 and 2011, respectively. We find that the Amazon basin lost 0.48 ± 0.18 petagrams of carbon per year (Pg C yr(-1)) during the dry year but was carbon neutral (0.06 ± 0.1 Pg C yr(-1)) during the wet year. Taking into account carbon losses from fire by using carbon monoxide measurements, we derived the basin net biome exchange (that is, the carbon flux between the non-burned forest and the atmosphere) revealing that during the dry year, vegetation was carbon neutral. During the wet year, vegetation was a net carbon sink of 0.25 ± 0.14 Pg C yr(-1), which is roughly consistent with the mean long-term intact-forest biomass sink of 0.39 ± 0.10 Pg C yr(-1) previously estimated from forest censuses. Observations from Amazonian forest plots suggest the suppression of photosynthesis during drought as the primary cause for the 2010 sink neutralization. Overall, our results suggest that moisture has an important role in determining the Amazonian carbon balance. If the recent trend of increasing precipitation extremes persists, the Amazon may become an increasing carbon source as a result of both emissions from fires and the suppression of net biome exchange by drought. PMID:24499918

  16. Chrysotile dissolution rates: Implications for carbon sequestration

    International Nuclear Information System (INIS)

    Highlights: • Uncertainties in serpentine dissolution kinetics hinder carbon sequestration models. • A pH dependent, far from equilibrium dissolution rate law for chrysotile. • Fchrysotile (mol/m2/s) = 10−0.21pH−10.57 at 22 °C over pH 2–10. • Laboratory dissolution rates consistent with mine waste weathering observations. • Potential for carbon sequestration in mine tailings and aquifers is assessed. - Abstract: Serpentine minerals (e.g., chrysotile) are a potentially important medium for sequestration of CO2 via carbonation reactions. The goals of this study are to report a steady-state, far from equilibrium chrysotile dissolution rate law and to better define what role serpentine dissolution kinetics will have in constraining rates of carbon sequestration via serpentine carbonation. The steady-state dissolution rate of chrysotile in 0.1 m NaCl solutions was measured at 22 °C and pH ranging from 2 to 8. Dissolution experiments were performed in a continuously stirred flow-through reactor with the input solutions pre-equilibrated with atmospheric CO2. Both Mg and Si steady-state fluxes from the chrysotile surface, and the overall chrysotile flux were regressed and the following empirical relationships were obtained: FMg=-0.22pH-10.02;FSi=-0.19pH-10.37;Fchrysotile=-0.21pH-10.57 where FMg, FSi, and Fchrysotile are the log10 Mg, Si, and molar chrysotile fluxes in mol/m2/s, respectively. Element fluxes were used in reaction-path calculations to constrain the rate of CO2 sequestration in two geological environments that have been proposed as potential sinks for anthropogenic CO2. Carbon sequestration in chrysotile tailings at 10 °C is approximately an order of magnitude faster than carbon sequestration in a serpentinite-hosted aquifer at 60 °C on a per kilogram of water basis. A serpentinite-hosted aquifer, however, provides a larger sequestration capacity. The chrysotile dissolution rate law determined in this study has important implications for

  17. Carbon dioxide-guided angioplasty

    International Nuclear Information System (INIS)

    Revascularization procedures are frequently necessary in patients with severe peripheral vascular disease and renal insufficiency (often coexistent with diabetes mellitus). This paper examines the use of carbon dioxide as the contrast agent in percutaneous revascularization procedures (balloon angioplasty). Over the past 10 months, our protocol has used CO2 as the contrast agent for balloon angioplasty in a select group of patients (n = 12) with peripheral vascular disease and renal insufficiency. Some had coexistent diabetes mellitus. With digital subtraction angiography, CO2 was the only contrast agent used during revascularization. Pressure gradients were obtained in appropriate patients

  18. Coordinated control of carbon and oxygen for ultra-low-carbon interstitial-free steel in a smelting process

    Institute of Scientific and Technical Information of China (English)

    Min Wang; Yan-ping Bao; Quan Yang; Li-hua Zhao; Lu Lin

    2015-01-01

    Low residual-free-oxygen before final de-oxidation was beneficial to improving the cleanness of ultra-low-carbon steel. For ul-tra-low-carbon steel production, the coordinated control of carbon and oxygen is a precondition for achieving low residual oxygen during the Ruhrstahl Heraeus (RH) decarburization process. In this work, we studied the coordinated control of carbon and oxygen for ultra-low-carbon steel during the basic oxygen furnace (BOF) endpoint and RH process using data statistics, multiple linear regressions, and thermodynamics computations. The results showed that the aluminum yield decreased linearly with increasing residual oxygen in liquid steel. When the mass ratio of free oxygen and carbon ([O]/[C]) in liquid steel before RH decarburization was maintained between 1.5 and 2.0 and the carbon range was from 0.030wt%to 0.040wt%, the residual oxygen after RH natural decarburization was low and easily controlled. To satisfy the re-quirement for RH decarburization, the carbon and free oxygen at the BOF endpoint should be controlled to be between 297 × 10−6 and 400 × 10−6 and between 574 × 10−6 and 775 × 10−6, respectively, with a temperature of 1695 to 1715°C and a furnace campaign of 1000 to 5000 heats.

  19. Coordinated control of carbon and oxygen for ultra-low-carbon interstitial-free steel in a smelting process

    Science.gov (United States)

    Wang, Min; Bao, Yan-ping; Yang, Quan; Zhao, Li-hua; Lin, Lu

    2015-12-01

    Low residual-free-oxygen before final de-oxidation was beneficial to improving the cleanness of ultra-low-carbon steel. For ultra-low-carbon steel production, the coordinated control of carbon and oxygen is a precondition for achieving low residual oxygen during the Ruhrstahl Heraeus (RH) decarburization process. In this work, we studied the coordinated control of carbon and oxygen for ultra-low-carbon steel during the basic oxygen furnace (BOF) endpoint and RH process using data statistics, multiple linear regressions, and thermodynamics computations. The results showed that the aluminum yield decreased linearly with increasing residual oxygen in liquid steel. When the mass ratio of free oxygen and carbon ([O]/[C]) in liquid steel before RH decarburization was maintained between 1.5 and 2.0 and the carbon range was from 0.030wt% to 0.040wt%, the residual oxygen after RH natural decarburization was low and easily controlled. To satisfy the requirement for RH decarburization, the carbon and free oxygen at the BOF endpoint should be controlled to be between 297 × 10-6 and 400 × 10-6 and between 574 × 10-6 and 775 × 10-6, respectively, with a temperature of 1695 to 1715°C and a furnace campaign of 1000 to 5000 heats.

  20. Transparent ultrathin conducting carbon films

    International Nuclear Information System (INIS)

    Ultrathin conductive carbon layers (UCCLs) were created by spin coating resists and subsequently converting them to conductive films by pyrolysis. Homogeneous layers as thin as 3 nm with nearly atomically smooth surfaces could be obtained. Layer characterization was carried out with the help of atomic force microscopy, profilometry, four-point probe measurements, Raman spectroscopy and ultraviolet-visible spectroscopy. The Raman spectra and high-resolution transmission electron microscopy image indicated that a glassy carbon like material was obtained after pyrolysis. The electrical properties of the UCCL could be controlled over a wide range by varying the pyrolysis temperature. Variation in transmittance with conductivity was investigated for applications as transparent conducting films. It was observed that the layers are continuous down to a thickness below 10 nm, with conductivities of 1.6 x 104 S/m, matching the best values observed for pyrolyzed carbon films. Further, the chemical stability of the films and their utilization as transparent electrochemical electrodes has been investigated using cyclic voltammetry and electrochemical impedance spectroscopy.

  1. 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

  2. Fire, carbon, and climate change

    International Nuclear Information System (INIS)

    One million hectares of forest are harvested in Canada annually, with 1 to 8 million hectares destroyed by fire and a further 10 to 25 million hectares consumed by insects. Enhanced disturbances have meant that Canadian forests are becoming carbon sources instead of carbon sinks. Canadian fire statistics from the year 1920 were provided along with a map of large fires between 1980 and 1999. A cycle of combustion losses, decomposition and regeneration of forests was presented, along with a stylized concept of forest carbon life cycles with fire. Direct emissions from forests fires were evaluated. An annual net ecosystem production in Canadian boreal forests and stand age was presented. Projections of areas burned were presented based on weather and fire danger relationships, with statistics suggesting that a 75 to 120 per cent increase is likely to occur by the end of this century. Trend observations show that areas burned are correlated with increasing temperature caused by anthropogenic effects. Prevention, detection, suppression and fuels management were presented as areas that needed improvement in fire management. However, management strategies may only postpone an increase in forest fires. Changes in disturbances such as fire and insects will be a significant early impact of climate change on forests. tabs., figs

  3. Microbially mediated mineral carbonation

    Science.gov (United States)

    Power, I. M.; Wilson, S. A.; Dipple, G. M.; Southam, G.

    2010-12-01

    Mineral carbonation involves silicate dissolution and carbonate precipitation, which are both natural processes that microorganisms are able to mediate in near surface environments (Ferris et al., 1994; Eq. 1). (Ca,Mg)SiO3 + 2H2CO3 + H2O → (Ca,Mg)CO3 + H2O + H4SiO4 + O2 (1) Cyanobacteria are photoautotrophs with cell surface characteristics and metabolic processes involving inorganic carbon that can induce carbonate precipitation. This occurs partly by concentrating cations within their net-negative cell envelope and through the alkalinization of their microenvironment (Thompson & Ferris, 1990). Regions with mafic and ultramafic bedrock, such as near Atlin, British Columbia, Canada, represent the best potential sources of feedstocks for mineral carbonation. The hydromagnesite playas near Atlin are a natural biogeochemical model for the carbonation of magnesium silicate minerals (Power et al., 2009). Field-based studies at Atlin and corroborating laboratory experiments demonstrate the ability of a microbial consortium dominated by filamentous cyanobacteria to induce the precipitation of carbonate minerals. Phototrophic microbes, such as cyanobacteria, have been proposed as a means for producing biodiesel and other value added products because of their efficiency as solar collectors and low requirement for valuable, cultivable land in comparison to crops (Dismukes et al., 2008). Carbonate precipitation and biomass production could be facilitated using specifically designed ponds to collect waters rich in dissolved cations (e.g., Mg2+ and Ca2+), which would allow for evapoconcentration and provide an appropriate environment for growth of cyanobacteria. Microbially mediated carbonate precipitation does not require large quantities of energy or chemicals needed for industrial systems that have been proposed for rapid carbon capture and storage via mineral carbonation (e.g., Lackner et al., 1995). Therefore, this biogeochemical approach may represent a readily

  4. Highly Efficient Oxidative Cleavage of Carbon-Carbon Double Bond over meso-Tetraphenyl Cobalt Porphyrin Catalyst in the Presence of Molecular Oxygen

    Institute of Scientific and Technical Information of China (English)

    周贤太; 纪红兵

    2012-01-01

    Highly efficient and selective carbon-carbon double bond aerobic cleavage of olefins catalyzed by metallopor- phyrins was investigated, and carbonyl compounds and epoxide were produced as the main products. CoTPP (co- balt meso-tetraphenyl porphyrin) showed excellent activity for the oxidative cleavage of carbon-carbon double bond by using styrene as model compound, in which the TOF (turnover frequency) and selectivity toward benzaldehyde was obtained with 2×10^4h-1 and 86%,respectively.

  5. Novel carbon nanostructures

    International Nuclear Information System (INIS)

    The discovery of carbon nanotubes in 1991 opened up a challenging new area of research, because they are expected to be ideal building blocks for nanoscale applications due to their extraordinary mechanical and electronic properties. Various production methods have been developed, however precise control of nanotube morphology (e.g. length, diameter) has yet to be realised, a fact which has delayed industrial exploitation. Thus a comprehensive understanding of nanotube growth is essential, and this thesis is concerned with this important problem, i.e. the controlled production of novel carbon nanomaterials. Chapter 1 surveys production methods for fullerenes, carbon nanotubes and other carbon-based materials, such as fibres, particles etc. The sophisticated tools required for this work, e.g. high resolution transmission electron microscopy (HRTEM), high resolution electron energy loss spectroscopy (HREELS), etc. are reviewed in Chapter 2. Chapter 3 describes a novel approach to carbon nanotubes, using laser etching techniques, which generates aligned tubes of uniform diameter and length. The mode of catalyst preparation, as well as the nature of the precursor, play crucial roles in this process. The preparation of modified carbon nanotubes by the pyrolysis of metallocene, e.g. ferrocene in conjunction with various hydrocarbons, is discussed in Chapter 4. Superconducting interference device measurements (SQUID) show that Fe-filled carbon nanotubes exhibit enhanced coercivities in the 430-1070 Oe range, i.e. greater than those reported for Ni and Co nanowires. Carbon nanotubes can be also modified by replacing atoms of the carbon network with nitrogen, boron or both. The creation of large arrays of nitrogen-doped carbon nanotubes, for example CNx nanofibres, as well as the formation of BxCyNz onions is described in Chapter 5. Electron irradiation of these onions generates pure carbon onions. Finally (Chapter 6), the catalytic behaviour of metal particles in different

  6. Polyoxometalates Pillared Hydrotalcite: Synthesis and Catalysis in Transesterification of Dimethyl Carbonate and Phenol

    Institute of Scientific and Technical Information of China (English)

    LUO Sheng-jun; CHI Ying-nan; HU Chang-wen

    2009-01-01

    o of phenol to DMC of 1∶1, a reaction time 10 h, and a catalyst amount 1%(wt), the conversion of phenol was 10.0%, the selectivities of diphenyl carbonate and methyl phenyl carbonate were 10.7% and 86.1%, respectively.

  7. New Carbons Made by Soft Chemistry

    Czech Academy of Sciences Publication Activity Database

    Kavan, Ladislav

    2001-01-01

    Roč. 200, Supplement (2001), s. 223-224. ISSN 0371-5345 R&D Projects: GA MŠk OC D14.10 Institutional research plan: CEZ:AV0Z4040901 Keywords : carbon * nanostructures * chemical modification Subject RIV: CF - Physical ; Theoretical Chemistry

  8. The Properties and Application of Carbon Nanostructures

    Czech Academy of Sciences Publication Activity Database

    Slepička, P.; Hubáček, T.; Kolská, Z.; Trostová, S.; Kasálková-Slepičková, N.; Bačáková, Lucie; Švorčík, V.

    Rijeka: InTech, 2013 - (Yilmaz, F.), s. 175-199 ISBN 978-953-51-0941-9 R&D Projects: GA ČR(CZ) GAP108/10/1106; GA ČR(CZ) GAP108/12/1168 Institutional support: RVO:67985823 Keywords : carbon nanostructures * properties * tissue engineering Subject RIV: JJ - Other Materials

  9. Method for Making a Carbon-Carbon Cylinder Block

    Science.gov (United States)

    Ransone, Phillip O. (Inventor)

    1997-01-01

    A method for making a lightweight cylinder block composed of carbon-carbon is disclosed. The use of carbon-carbon over conventional materials. such as cast iron or aluminum, reduces the weight of the cylinder block and improves thermal efficiency of the internal combustion reciprocating engine. Due to the negligible coefficient of thermal expansion and unique strength at elevated temperatures of carbon-carbon, the piston-to-cylinder wall clearance can be small, especially when the carbon-carbon cylinder block is used in conjunction with a carbon-carbon piston. Use of the carbon-carbon cylinder block has the effect of reducing the weight of other reciprocating engine components allowing the piston to run at higher speeds and improving specific engine performance.

  10. Transcutaneous estimation of arterial carbon dioxide in intensive care. Which electrode temperature?

    OpenAIRE

    Cheriyan, G; Helms, P; Paky, F; Marsden, D.; Chiu, M. C.

    1986-01-01

    Transcutaneous and arterial carbon dioxide were measured simultaneously in 57 children (age range 10 days to 14.3 years) undergoing intensive care. All were haemodynamically stable at the time of study. Mean calibration time with 5 and 10% carbon dioxide was 43 (range 38-58) minutes and mean arterialisation time was 10.5 (range 3-30) minutes. Duplicate hourly arterial samples over a four hour period showed that transcutaneous: arterial carbon dioxide correlation was independent of electrode t...

  11. Carbon sequestration via wood burial

    Directory of Open Access Journals (Sweden)

    Zeng Ning

    2008-01-01

    Full Text Available Abstract To mitigate global climate change, a portfolio of strategies will be needed to keep the atmospheric CO2 concentration below a dangerous level. Here a carbon sequestration strategy is proposed in which certain dead or live trees are harvested via collection or selective cutting, then buried in trenches or stowed away in above-ground shelters. The largely anaerobic condition under a sufficiently thick layer of soil will prevent the decomposition of the buried wood. Because a large flux of CO2 is constantly being assimilated into the world's forests via photosynthesis, cutting off its return pathway to the atmosphere forms an effective carbon sink. It is estimated that a sustainable long-term carbon sequestration potential for wood burial is 10 ± 5 GtC y-1, and currently about 65 GtC is on the world's forest floors in the form of coarse woody debris suitable for burial. The potential is largest in tropical forests (4.2 GtC y-1, followed by temperate (3.7 GtC y-1 and boreal forests (2.1 GtC y-1. Burying wood has other benefits including minimizing CO2 source from deforestation, extending the lifetime of reforestation carbon sink, and reducing fire danger. There are possible environmental impacts such as nutrient lock-up which nevertheless appears manageable, but other concerns and factors will likely set a limit so that only part of the full potential can be realized. Based on data from North American logging industry, the cost for wood burial is estimated to be $14/tCO2($50/tC, lower than the typical cost for power plant CO2 capture with geological storage. The cost for carbon sequestration with wood burial is low because CO2 is removed from the atmosphere by the natural process of photosynthesis at little cost. The technique is low tech, distributed, easy to monitor, safe, and reversible, thus an attractive option for large-scale implementation in a world-wide carbon market.

  12. Carbon compound used in hydrogen storage; Compuesto de carbon utilizado en almacenamiento de hidrogeno

    Energy Technology Data Exchange (ETDEWEB)

    Iturbe G, J.L.; Lopez M, B.E. [ININ, 52045 Ocoyoacac, Estado de Mexico (Mexico)

    2004-07-01

    In the present work it is studied the activated carbon of mineral origin for the sorption of hydrogen. The carbon decreased of particle size by means of the one alloyed mechanical. The time of mill was of 10 hours. The characterization one carries out by scanning electron microscopy and X-ray diffraction. The hydrogen sipped in the carbon material it was determined using the Thermal gravimetric method (TGA). The conditions of hydrogenation went at 10 atm of pressure and ambient temperature during 18 hours. They were also carried out absorption/desorption cycles of hydrogen in the same one system of thermal gravimetric analysis. The results showed percentages of sorption of 2% approximately in the cycles carried out in the system TGA and of 4.5% in weight of hydrogen at pressure of 10 atmospheres and ambient temperature during 18 hours. (Author)

  13. Carbon Stock and Carbon Cycle of Wetland Ecosystem

    OpenAIRE

    Zeng, Zhangquan; Zhang, Canming; LI, JIAO; Yang, Nan; Li, Xiquan; Niu, Yandong; Wu, Zijian

    2014-01-01

    Wetland ecosystem is an essential ecosystem in the world. Its organic carbon stock and carbon cycle are important basis of global carbon cycle researches and also major contents of global climate change researches. Researches have shown that wetland protection and restoration can promote carbon accumulation and reduce emission of greenhouse gases. This paper discussed influence of carbon stock and carbon balance of wetland ecosystem and emission of greenhouse gases, as well as the relationshi...

  14. NON-DESTRUCTIVE SOIL CARBON ANALYZER.

    Energy Technology Data Exchange (ETDEWEB)

    Wielopolski, Lucian; Hendrey, G.; Orion, I.; Prior, S.; Rogers, H.; Runion, B.; Torbert, A.

    2004-02-01

    This report describes the feasibility, calibration, and safety considerations of a non-destructive, in situ, quantitative, volumetric soil carbon analytical method based on inelastic neutron scattering (INS). The method can quantify values as low as 0.018 gC/cc, or about 1.2% carbon by weight with high precision under the instrument's configuration and operating conditions reported here. INS is safe and easy to use, residual soil activation declines to background values in under an hour, and no radiological requirements are needed for transporting the instrument. The labor required to obtain soil-carbon data is about 10-fold less than with other methods, and the instrument offers a nearly instantaneous rate of output of carbon-content values. Furthermore, it has the potential to quantify other elements, particularly nitrogen. New instrumentation was developed in response to a research solicitation from the U.S. Department of Energy (DOE LAB 00-09 Carbon Sequestration Research Program) supporting the Terrestrial Carbon Processes (TCP) program of the Office of Science, Biological and Environmental Research (BER). The solicitation called for developing and demonstrating novel techniques for quantitatively measuring changes in soil carbon. The report includes raw data and analyses of a set of proof-of-concept, double-blind studies to evaluate the INS approach in the first phase of developing the instrument. Managing soils so that they sequester massive amounts of carbon was suggested as a means to mitigate the atmospheric buildup of anthropogenic CO{sub 2}. Quantifying changes in the soils' carbon stocks will be essential to evaluating such schemes and documenting their performance. Current methods for quantifying carbon in soil by excavation and core sampling are invasive, slow, labor-intensive and locally destroy the system being observed. Newly emerging technologies, such as Laser Induced Breakdown Spectroscopy and Near-Infrared Spectroscopy, offer soil-carbon

  15. Carbon Monoxide Information Center

    Medline Plus

    Full Text Available ... Consumers Businesses Contact CPSC Website Design Feedback Consumers: Español Businesses: Español , 中文 , Tiếng Việt Connect with Us : Twitter YouTube ... Safely Home / Safety Education / Safety Education Centers En Español Carbon Monoxide Information Center The Invisible Killer Carbon ...

  16. Carbon dioxide recycling

    Science.gov (United States)

    The recycling of carbon dioxide to methanol and dimethyl ether is seen to offer a substantial route to renewable and environmentally carbon neutral fuels. One of the authors has championed the “Methanol Economy" in articles and a book. By recycling ambient CO2, the authors argue ...

  17. Carbon Capture and Storage

    NARCIS (Netherlands)

    Benson, S.M.; Bennaceur, K.; Cook, P.; Davison, J.; Coninck, H. de; Farhat, K.; Ramirez, C.A.; Simbeck, D.; Surles, T.; Verma, P.; Wright, I.

    2012-01-01

    Emissions of carbon dioxide, the most important long-lived anthropogenic greenhouse gas, can be reduced by Carbon Capture and Storage (CCS). CCS involves the integration of four elements: CO 2 capture, compression of the CO2 from a gas to a liquid or a denser gas, transportation of pressurized CO 2

  18. Carbon black recovery

    International Nuclear Information System (INIS)

    A process and apparatus for recovering carbon black from hot smoke which comprises passing the smoke through a cyclone separation zone following cooling, then through aggregate filter beds and regeneration of filter beds with clean off-gas which is recycled to the carbon black reaction zone as quench

  19. Seeing the Carbon Cycle

    Science.gov (United States)

    Drouin, Pamela; Welty, David J.; Repeta, Daniel; Engle-Belknap, Cheryl A.; Cramer, Catherine; Frashure, Kim; Chen, Robert

    2006-01-01

    In this article, the authors present a classroom experiment that was developed to introduce middle school learners to the carbon cycle. The experiment deals with transfer of CO[subscript 2] between liquid reservoirs and the effect CO[subscript 2] has on algae growth. It allows students to observe the influence of the carbon cycle on algae growth,…

  20. The carbon cycle revisited

    Science.gov (United States)

    Bolin, Bert; Fung, Inez

    1992-01-01

    Discussions during the Global Change Institute indicated a need to present, in some detail and as accurately as possible, our present knowledge about the carbon cycle, the uncertainties in this knowledge, and the reasons for these uncertainties. We discuss basic issues of internal consistency within the carbon cycle, and end by summarizing the key unknowns.

  1. Amorphous iron (II) carbonate

    DEFF Research Database (Denmark)

    Sel, Ozlem; Radha, A.V.; Dideriksen, Knud;

    2012-01-01

    Abstract The synthesis, characterization and crystallization energetics of amorphous iron (II) carbonate (AFC) are reported. AFC may form as a precursor for siderite (FeCO3). The enthalpy of crystallization (DHcrys) of AFC is similar to that of amorphous magnesium carbonate (AMC) and more...

  2. Fly ash carbon passivation

    Science.gov (United States)

    La Count, Robert B; Baltrus, John P; Kern, Douglas G

    2013-05-14

    A thermal method to passivate the carbon and/or other components in fly ash significantly decreases adsorption. The passivated carbon remains in the fly ash. Heating the fly ash to about 500 and 800 degrees C. under inert gas conditions sharply decreases the amount of surfactant adsorbed by the fly ash recovered after thermal treatment despite the fact that the carbon content remains in the fly ash. Using oxygen and inert gas mixtures, the present invention shows that a thermal treatment to about 500 degrees C. also sharply decreases the surfactant adsorption of the recovered fly ash even though most of the carbon remains intact. Also, thermal treatment to about 800 degrees C. under these same oxidative conditions shows a sharp decrease in surfactant adsorption of the recovered fly ash due to the fact that the carbon has been removed. This experiment simulates the various "carbon burnout" methods and is not a claim in this method. The present invention provides a thermal method of deactivating high carbon fly ash toward adsorption of AEAs while retaining the fly ash carbon. The fly ash can be used, for example, as a partial Portland cement replacement in air-entrained concrete, in conductive and other concretes, and for other applications.

  3. Carbon Monoxide Poisoning

    Science.gov (United States)

    ... natural gas, propane, oil, and methane) burn incompletely. ** Carbon Monoxide can have different effects on people based on its concentration in the air that people breathe, and the person’s health condition.**** Each year, carbon monoxide poisoning claims approximately 480 lives and sends another ...

  4. Carbon for sensing devices

    CERN Document Server

    Tagliaferro, Alberto

    2015-01-01

    This book reveals why carbon is playing such an increasingly prominent role as a sensing material. The various steps that transform a raw material in a sensing device are thoroughly presented and critically discussed.  The authors deal with all aspects of carbon-based sensors, starting from the various hybridization and allotropes of carbon, with specific focus on micro and nanosized carbons (e.g., carbon nanotubes, graphene) and their growth processes. The discussion then moves to the role of functionalization and the different routes to achieve it. Finally, a number of sensing applications in various fields are presented, highlighting the connection with the basic properties of the various carbon allotropes.  Readers will benefit from this book’s bottom-up approach, which starts from the local bonding in carbon solids and ends with sensing applications, linking the local hybridization of carbon atoms and its modification by functionalization to specific device performance. This book is a must-have in th...

  5. Carbon Dioxide Fountain

    Science.gov (United States)

    Kang, Seong-Joo; Ryu, Eun-Hee

    2007-01-01

    This article presents the development of a carbon dioxide fountain. The advantages of the carbon dioxide fountain are that it is odorless and uses consumer chemicals. This experiment also is a nice visual experiment that allows students to see evidence of a gaseous reagent being consumed when a pressure sensor is available. (Contains 3 figures.)…

  6. De-carbonizingChina

    Institute of Scientific and Technical Information of China (English)

    zhou; Xiaoyan

    2013-01-01

    Innovation in the energy sector will pave the way for the country’slow-carbon future Although its per-capita emission is roughly on par with the world’s average, China is the world’s largest carbon dioxide emitter,

  7. COMMITTED TO CARBON REDUCTION

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    Chinese efforts to lower carbon emissions through environmentally friendly means begin gaining momentum Efforts to curb carbon emissions continue to take shape as China adheres to its pledge for a brighter, greener future. More importantly, as environmental measures take hold and develop

  8. Soil Carbon Sequestration in India

    International Nuclear Information System (INIS)

    With a large land area and diverse ecoregions, there is a considerable potential of terrestrial/soil carbon sequestration in India. Of the total land area of 329 million hectares (Mha), 297 Mha is the land area comprising 162 Mha of arable land, 69 Mha of forest and woodland, 11 Mha of permanent pasture, 8 Mha of permanent crops and 58 Mha is other land uses. The soil organic carbon (SOC) pool is estimated at 21 Pg (petagram = Pg = 1 x 1015 g billion ton) to 30-cm depth and 63 Pg to 150-cm depth. The soil inorganic carbon (SIC) pool is estimated at 196 Pg to 1-m depth. The SOC concentration in most cultivated soils is less than 5 g/kg compared with 15 to 20 g/kg in uncultivated soils. Low SOC concentration is attributed to plowing, removal of crop residue and other biosolids, and mining of soil fertility. Accelerated soil erosion by water leads to emission of 6 Tg C/y. Important strategies of soil C sequestration include restoration of degraded soils, and adoption of recommended management practices (RMPs) of agricultural and forestry soils. Potential of soil C sequestration in India is estimated at 7 to 10 Tg C/y for restoration of degraded soils and ecosystems, 5 to 7 Tg C/y for erosion control, 6 to 7 Tg C/y for adoption of RMPs on agricultural soils, and 22 to 26 Tg C/y for secondary carbonates. Thus, total potential of soil C sequestration is 39 to 49 (44± 5) Tg C/y

  9. Carbon-ionogel supercapacitors for integrated microelectronics.

    Science.gov (United States)

    Leung, Greg; Smith, Leland; Lau, Jonathan; Dunn, Bruce; Chui, Chi On

    2016-01-22

    To exceed the performance limits of dielectric capacitors in microelectronic circuit applications, we design and demonstrate on-chip coplanar electric double-layer capacitors (EDLCs), or supercapacitors, employing carbon-coated gold electrodes with ionogel electrolyte. The formation of carbon-coated microelectrodes is accomplished by solution processing and results in a ten-fold increase in EDLC capacitance compared to bare gold electrodes without carbon. At frequencies up to 10 Hz, an areal capacitance of 2.1 pF μm(-2) is achieved for coplanar carbon-ionogel EDLCs with 10 μm electrode gaps and 0.14 mm(2) electrode area. Our smallest devices, comprised of 5 μm electrode gaps and 80 μm(2) of active electrode area, reach areal capacitance values of ∼0.3 pF μm(-2) at frequencies up to 1 kHz, even without carbon. To our knowledge, these are the highest reported values to date for on-chip EDLCs with sub-mm(2) areas. A physical EDLC model is developed through the use of computer-aided simulations for design exploration and optimization of coplanar EDLCs. Through modeling and comparison with experimental data, we highlight the importance of reducing the electrode gap and electrolyte resistance to achieve maximum performance from on-chip EDLCs. PMID:26650708

  10. Lithium storage properties of multiwall carbon nanotubes prepared by CVD

    International Nuclear Information System (INIS)

    Full text: Multiwall carbon nanotubes (MWCNTs) were synthesised by chemical vapour deposition (CVD) method using acetylene gas. The XRD pattern of as prepared carbon nanotubes showed that the d002 value is 3.44 Angstroms. The morphology and microstructure of carbon nanotubes were characterized by HRTEM. Most of carbon nanotubes are entangled together to form bundles or ropes. The diameter of the carbon nanotubes is in the range of 10 ∼ 20 nm. There is a small amount of amorphous carbon particles presented in the sample. However, the yield of carbon nanotubes is more than 95%. Electrochemical properties of carbon nanotubes were characterised via a variety of electrochemical testing techniques. The result of CV test showed that the Li insertion potential is quite low, which is very close to O V versus Li+/Li reference electrode, whereas the potential for Li de-intercalation is in the range of 0.2-0.4 V. There exists a slight voltage hysteresis between Li intercalation and Li de-intercalation, which is similar to the other carbonaceous materials. The intensity of redox peaks of carbon nanotubes decrease with scanning cycle, indicating that the reversible Li insertion capacity gradually decreases. The carbon nanotubes electrode demonstrated a reversible lithium storage capacity of 340 mAh/g with good cyclability at moderate current density. Further improvement of Li storage capacity is possible by opening the end of carbon nanotubes to allow lithium insertion into inner graphene sheet of carbon nanotubes. The kinetic properties of lithium insertion in carbon nanotube electrodes were characterised by a.c. impedance measurements. It was found that the lithium diffusion coefficient dLi decreases with an increase of Li ion concentration in carbon nanotube host

  11. E10 Orbifolds

    Energy Technology Data Exchange (ETDEWEB)

    Brown, Jeffrey; Ganguli, Surya; Ganor, Ori J.; Helfgott, Craig

    2005-04-28

    We study Z2 orbifolds of M-theory in terms of E10. We find a simple relation between the Z2 action on E10 and the imaginary root that corresponds [hep-th/0401053]to the"twisted sector" branes. We discuss the connection between the Kac-Moody algebra DE10 and the"untwisted" sector, and we demonstrate how DE18 can describe both the untwisted and twisted sectors simultaneously.

  12. Windows 10 for dummies

    CERN Document Server

    Rathbone, Andy

    2015-01-01

    The fast and easy way to get up and running with Windows 10 Windows 10 For Dummies covers the latest version of Windows and gets you up and running with the changes and new features you'll find in this updated operating system. Packed with time-saving tips to help you get the most out of the software, this helpful Windows 10 guide shows you how to manage Windows tasks like navigating the interface with a mouse or touchscreen, connecting to the web, and troubleshooting problems and making quick fixes. Assuming no prior knowledge of the software, Windows 10 For Dummies addresses the updates to

  13. Windows 10 simplified

    CERN Document Server

    McFedries, Paul

    2015-01-01

    Learn Windows 10 quickly and painlessly with this beginner's guide Windows 10 Simplified is your absolute beginner's guide to the ins and outs of Windows. Fully updated to cover Windows 10, this highly visual guide covers all the new features in addition to the basics, giving you a one-stop resource for complete Windows 10 mastery. Every page features step-by-step screen shots and plain-English instructions that walk you through everything you need to know, no matter how new you are to Windows. You'll master the basics as you learn how to navigate the user interface, work with files, create

  14. Progressing towards post-2012 carbon markets

    Energy Technology Data Exchange (ETDEWEB)

    Soeren Luetken, S.; Holm Olsen, K.

    2011-11-15

    Confronting the end of the first Kyoto Commitment period in 2012 with no agreed outcome for global cooperation on future emission reductions, there is an urgent need to look for new opportunities for public and private cooperation to drive broad-based progress in living standards and keep projected future warming below the politically agreed 2 degrees Celsius. Responding jointly to these global challenges the United Nations environmental Program (UNEP) and its UNEP Risoe Centre (URC) have in cooperation with the Global Green Growth Institute (GGGI) prepared the Perspectives 2011. The publication focuses on the role of carbon markets in contributing to low carbon development and new mechanisms for green growth, as one core area of action to address the challenges noted above. The publication explores in ten articles, how carbon markets at national, regional and global levels can be developed and up-scaled to sustain the involvement of the private sector in leveraging finance and innovative solutions to reduce greenhouse gas emissions. The titles of the ten articles are: 1) Fragmentation of international climate policy - doom or boom for carbon markets?; 2) Perspectives on the EU carbon market; 3) China carbon market; 4) The national context of U.S. state policies for a global commons problem; 5) Mind the gap - the state-of-play of Canadian greenhouse gas mitigation; 6) Role of the UN and multilateral policies in integrating an increasingly fragmented global carbon market; 7) Making CDM work for poor and rich Africa beyond 2012 - a series of dos and don'ts; 8) Voluntary market - future perspectives; 9) Sectoral approaches as a way forward for the carbon market?; 10) The Durban outcome - a post 2012 framework approach for green house gas markets. (LN)

  15. Deep Soil: Quantifying and Modeling Subsurface Carbon

    Science.gov (United States)

    James, J. N.; Devine, W.; Harrison, R. B.

    2014-12-01

    Some soil carbon datasets that are spatially rich, such as the USDA Forest Service Inventory and Analysis National Program dataset, sample soil to only 20 cm (8 inches), despite evidence that substantial stores of soil C can be found deeper in the soil profile. The maximum extent of tree rooting is typically many meters deep and provides: direct exchange with the soil solution; redistribution of water from deep horizons toward the surface during times of drought; resources for active microbial communities in deep soil around root channels; and direct carbon inputs through exudates and root turnover. This study examined soil carbon to a depth of 2.5 meters across 22 soils in Pacific Northwest Douglas-fir forests. Excavations at 20 additional sites took place in summer 2014, greatly expanding the spatial coverage and extent of the data set. Forest floor and mineral soil bulk density samples were collected at depths of 0.1, 0.5, 1.0, 1.5, 2.0 and 2.5 meters. Pool estimates from systematic sampling depths shallower than 1.5 m yielded significantly smaller estimates than the total soil stock to 2.5 meters (PAndisols with non-crystalline minerals, which can adsorb large quantities of carbon on mineral surfaces and preserve it from decomposition. An accurate spatial dataset of soil depth to bedrock would be extremely useful to constrain models of the vertical distribution of soil carbon. Efforts to represent carbon in spatial models would benefit from considering the vertical distribution of carbon in soil. Sampling deep soil will avoid biased estimates of soil carbon and create a more complete picture of soil pools and changes over time.

  16. Recombination of atomic oxygen and hydrogen on amorphous carbon

    International Nuclear Information System (INIS)

    Deposit buildup and fuel entrapment due to amorphous carbon are relevant issues in fusion devices with carbon based plasma facing components. Neutral atomic species play a significant role – atomic hydrogen facilitates the formation of amorphous carbon while atomic oxygen could be used to remove carbon deposits. The kinetics of either reaction depends on the density of neutral species, which in turn is influenced by recombination on the vessel walls. In this work, we measured the probability of heterogeneous recombination of atomic hydrogen and oxygen on amorphous carbon deposits. The recombination coefficients were determined by observing density profiles of atomic species in a closed side-arm of a plasma vessel with amorphous carbon deposit-lined walls. Density profiles were measured with fiber optics catalytic probes. The source of atomic species was inductively coupled radiofrequency plasma. The measured recombination coefficient values were of the order of 10−3 for both species

  17. Carbon activation process for increased surface accessibility in electrochemical capacitors

    Science.gov (United States)

    Doughty, Daniel H.; Eisenmann, Erhard T.

    2001-01-01

    A process for making carbon film or powder suitable for double capacitor electrodes having a capacitance of up to about 300 F/cm.sup.3 is disclosed. This is accomplished by treating in aqueous nitric acid for a period of about 5 to 15 minutes thin carbon films obtained by carbonizing carbon-containing polymeric material having a high degree of molecular directionality, such as polyimide film, then heating the treated carbon film in a non-oxidizing atmosphere at a non-graphitizing temperature of at least 350.degree. C. for about 20 minutes, and repeating alternately the nitric acid step and the heating step from 7 to 10 times. Capacitors made with this carbon may find uses ranging from electronic devices to electric vehicle applications.

  18. Low Carbon Supplier Selection in the Hotel Industry

    Directory of Open Access Journals (Sweden)

    Chia-Wei Hsu

    2014-05-01

    Full Text Available This study presents a model for evaluating the carbon and energy management performance of suppliers by using multiple-criteria decision-making (MCDM. By conducting a literature review and gathering expert opinions, 10 criteria on carbon and energy performance were identified to evaluate low carbon suppliers using the Fuzzy Delphi Method (FDM. Subsequently, the decision-making trial and evaluation laboratory (DEMATEL method was used to determine the importance of evaluation criteria in selecting suppliers and the causal relationships between them. The DEMATEL-based analytic network process (DANP and VlseKriterijumska Optimizacija I Kompromisno Resenje (VIKOR were adopted to evaluate the weights and performances of suppliers and to obtain a solution under each evaluation criterion. An illustrative example of a hotel company was presented to demonstrate how to select a low carbon supplier according to carbon and energy management. The proposed hybrid model can help firms become effective in facilitating low carbon supply chains in hotels.

  19. Pesticide sorption by low organic carbon sediments: A sceening for seven herbicides

    DEFF Research Database (Denmark)

    Madsen, Lene; Lindhardt, Bo; Rosenberg, Per;

    2000-01-01

    The sorption of seven pesticides in 10 Danish aquifer sediments has been studied. These sediments all have a total organic carbon (TOC) content below 1 g kg(-1), and include carbonate-bearing and carbonate-free Quatenary sand deposits and a Cretaceous chalk aquifer. Batch experiments were carried...

  20. Studies on the sublimation of tungsten single crystal (110) face and the influence of carbon

    International Nuclear Information System (INIS)

    Evaporation of tungsten single crystals face (110) is studied in ultrahigh vacuum (better than 1x10-9 torr) by Langmuir method. Small admixtures of carbon are shown to markedly influence the process. Carbon hinders the evaporation and increases the sublimation energy by 25 kcal. The data obtained show that the reported parametres of tungsten evaporation refer to a carbon-containing material

  1. Adhesion, differentiation and immune activation of human osteogenic cells in cultures on carbon-fibre reinforced carbon composites

    Czech Academy of Sciences Publication Activity Database

    Bačáková, Lucie; Starý, V.; Glogar, Petr; Lisá, Věra

    2003-01-01

    Roč. 6, - (2003), s. 8-9. ISSN 1429-7248. [Konferencja Naukowa "Biomaterialy w medycynie i weterynarii" /13./. Rytro, 09.10.2003-12.10.2003] R&D Projects: GA MŠk OC 527.130 Institutional research plan: CEZ:AV0Z3046908; CEZ:AV0Z5011922 Keywords : carbon-carbon composites * surface properties * bone tissue engineering Subject RIV: JI - Composite Materials

  2. Potential Carbon Negative Commercial Aviation through Land Management

    Science.gov (United States)

    Hendricks, Robert C.

    2007-01-01

    Brazilian terra preta soil and char-enhanced soil agricultural systems have demonstrated both enhanced plant biomass and crop yield and functions as a carbon sink. Similar carbon sinking has been demonstrated for both glycophyte and halophyte plants and plant roots. Within the assumption of 3.7 t-C/ha/yr soils and plant root carbon sinking, it is possible to provide carbon neutral U.S. commercial aviation using about 8.5% of U.S. arable lands. The total airline CO2 release would be offset by carbon credits for properly managed soils and plant rooting, becoming carbon neutral for carbon sequestered synjet processing. If these lands were also used to produce biomass fuel crops such as soybeans at an increased yield of 60 bu/acre (225gal/ha), they would provide over 3.15 10(exp 9) gallons biodiesel fuel. If all this fuel were refined into biojet it would provide a 16% biojet-84% synjet blend. This allows the U.S. aviation industry to become carbon negative (carbon negative commercial aviation through carbon credits). Arid land recovery could yield even greater benefits.

  3. Carbon storage and recycling in short-rotation energy crops

    International Nuclear Information System (INIS)

    Short-rotation energy crops can play a significant role in storing carbon compared to the agricultural land uses they would displace. However, the benefits from these plantations in avoiding further use of fossil fuel and in taking pressure off of native forests for energy uses provides longer term carbon benetfits than the plantation carbon sequestration itself. The fast growth and harvest frequency of plantations tends to limit the amount of above and below-ground carbon storage in them. The primary components of plantation carbon sequestering compared to sustained agricultural practices involve above-ground wood, possible increased soil carbon, litter layer formation, and increased root biomass. On the average, short-rotation plantations in total may increase carbon inventories by about 30 to 40 tonnes per hectare over about a 20- to 56-year period when displacing cropland. This is about doubling in storage over cropland and about one-half the storage in human-impacted forests. The sequestration benefit of wood energy crops over cropland would be negated in about 75 to 100 years by the use of fossil fuels to tend the plantations and handle biomass. Plantation interactions with other land uses and total landscape carbon inventory is important in assessing the relative role plantations play in terrestrial and atmospheric carbon dynamics. It is speculated that plantations, when viewed in this context. could trencrate a global leveling of net carbon emissions for approximately 10 to 20 years

  4. Microbial Enzyme Activity and Carbon Cycling in Grassland Soil Fractions

    Science.gov (United States)

    Allison, S. D.; Jastrow, J. D.

    2004-12-01

    Extracellular enzymes are necessary to degrade complex organic compounds present in soils. Using physical fractionation procedures, we tested whether old soil carbon is spatially isolated from degradative enzymes across a prairie restoration chronosequence in Illinois, USA. We found that carbon-degrading enzymes were abundant in all soil fractions, including macroaggregates, microaggregates, and the clay fraction, which contains carbon with a mean residence time of ~200 years. The activities of two cellulose-degrading enzymes and a chitin-degrading enzyme were 2-10 times greater in organic matter fractions than in bulk soil, consistent with the rapid turnover of these fractions. Polyphenol oxidase activity was 3 times greater in the clay fraction than in the bulk soil, despite very slow carbon turnover in this fraction. Changes in enzyme activity across the restoration chronosequence were small once adjusted for increases in soil carbon concentration, although polyphenol oxidase activity per unit carbon declined by 50% in native prairie versus cultivated soil. These results are consistent with a `two-pool' model of enzyme and carbon turnover in grassland soils. In light organic matter fractions, enzyme production and carbon turnover both occur rapidly. However, in mineral-dominated fractions, both enzymes and their carbon substrates are immobilized on mineral surfaces, leading to slow turnover. Soil carbon accumulation in the clay fraction and across the prairie restoration chronosequence probably reflects increasing physical isolation of enzymes and substrates on the molecular scale, rather than the micron to millimeter scale.

  5. CARBON DIOXIDE CAPTURE FROM FLUE GAS USING DRY REGENERABLE SORBENTS

    Energy Technology Data Exchange (ETDEWEB)

    David A. Green; Thomas Nelson; Brian S. Turk; Paul Box; Weijiong Li; Raghubir P. Gupta

    2005-07-01

    This report describes research conducted between April 1, 2005 and June 30, 2005 on the use of dry regenerable sorbents for removal of carbon dioxide from flue gas from coal combustion and synthesis gas from coal gasification. Supported sodium carbonate sorbents removed up to 76% of the carbon dioxide from simulated flue gas in a downflow cocurrent flow reactor system, with an approximate 15 second gas-solid contact time. This reaction proceeds at temperatures as low as 25 C. Lithium silicate sorbents remove carbon dioxide from high temperature simulated flue gas and simulated synthesis gas. Both sorbent types can be thermally regenerated and reused. The lithium silicate sorbent was tested in a thermogravimetric analyzer and in a 1-in quartz reactor at atmospheric pressure; tests were also conducted at elevated pressure in a 2-in diameter high temperature high pressure reactor system. The lithium sorbent reacts rapidly with carbon dioxide in flue gas at 350-500 C to absorb about 10% of the sorbent weight, then continues to react at a lower rate. The sorbent can be essentially completely regenerated at temperatures above 600 C and reused. In atmospheric pressure tests with synthesis gas of 10% initial carbon dioxide content, the sorbent removed over 90% of the carbon dioxide. An economic analysis of a downflow absorption process for removal of carbon dioxide from flue gas with a supported sodium carbonate sorbent suggests that a 90% efficient carbon dioxide capture system installed at a 500 MW{sub e} generating plant would have an incremental capital cost of $35 million ($91/kWe, assuming 20 percent for contingencies) and an operating cost of $0.0046/kWh. Assuming capital costs of $1,000/kW for a 500 MWe plant the capital cost of the down flow absorption process represents a less than 10% increase, thus meeting DOE goals as set forth in its Carbon Sequestration Technology Roadmap and Program Plan.

  6. Basalt catalyzed carbonate precipitation reactions using carbon dioxide at low temperatures and low pressures

    Science.gov (United States)

    Petrik-Huff, C.; Finkelstein, D. B.; Mabee, S. B.

    2011-12-01

    Increased attention is being paid to basalts as host formations for the geologic sequestration of anthropogenically produced CO2. Here, we present preliminary results of batch experiments conducted on basalts from the Hartford Basin, the Deerfield and the Holyoke Basalt, to better constrain the optimum conditions to maximize carbon sequestration through the precipitation of carbonate. The purpose of this work is to explore options for CO2 sequestration in a locality where there is a lack of large geologic reservoirs appropriate for storage. In these experiments, 10 grams of 400 micron Deerfield and Holyoke basalt was reacted with deionized water for three hours both at and below supercritical conditions. These experiments showed carbonate precipitation of 15% was consistent at low pressures of CO2 (800 psi) both at high (100 Celsius) and low (20 Celsius) temperatures. These ranges of carbonate precipitation were greatest (15%) when CO2 was at low pressures. Experiments conducted at supercritical conditions precipitated a maximum of 4.7% carbonate. This information is valuable when considering alternative sequestration mechanisms that could be operated adjacent to power generation facilities or more industrial pure sources of CO2. The possibility of low pressure/temperature sequestration reactors to be operated in areas where transport to regional or national sequestration facilities may be cost prohibitive is a parallel course of action that should also be considered. Additionally, it is important to consider how a small ex-situ carbon sequestration project can help increase public acceptance of carbon capture and sequestration.

  7. Coenzyme Q10 (PDQ)

    Science.gov (United States)

    ... and use of CoQ10 as a complementary or alternative treatment for cancer? CoQ10 was first identified in 1957. Its chemical ... of CAM therapies originally considered to be purely alternative approaches are finding a place in cancer treatment—not as cures, but as complementary therapies that ...

  8. ENLIGHT 10 year Anniversary

    CERN Multimedia

    Alvarez, Paul

    2012-01-01

    Ten years ago, in February 2002, the European Network for Light Ion Hadron Therapy (ENLIGHT) had its inaugural meeting at CERN. As a pioneering multidisciplinary network celebrates its 10th anniversary, some of the founders recall how it all started. Picture 1 : Participants at the 10th anniversary meeting of ENLIGHT at CNAO, Pavia, in September 2012.

  9. Scaling of carbon erosion in Tore Supra

    Energy Technology Data Exchange (ETDEWEB)

    Marandet, Y., E-mail: yannick.marandet@univ-provence.fr [PIIM, CNRS-Universite de Provence, Marseille (France); Dachicourt, R.; Monier-Garbet, P.; Tsitrone, E. [Association Euratom-CEA, CEA/DSM/IRFM, CEA Cadarache (France); Reiter, D.; Boerner, P. [IEF-4 Plasmaphysik, Forschungszentrum Juelich GmbH, Association EURATOM-FZJ, TEC (Germany); Beaute, A.; Delchambre, E. [Association Euratom-CEA, CEA/DSM/IRFM, CEA Cadarache (France); Genesio, P. [PIIM, CNRS-Universite de Provence, Marseille (France); Naiim-Habib, M.; Gunn, J.P.; Kubic, M.; Pegourie, B.; Aniel, T.; Brosset, C.; Colledani, G.; Corre, Y.; Gauthier, E.; Martinez, A. [Association Euratom-CEA, CEA/DSM/IRFM, CEA Cadarache (France)

    2011-08-01

    The scaling law for carbon erosion in Tore Supra previously established by Hogan et al. ({Phi}{sub C}(C/s) = 5 x 10{sup 20}P{sub cond} (MW), where P{sub cond} is the conducted power) is revisited both from the experimental and the modelling point of view. New developments with the EIRENE code, that allow relating measured CII emission intensities to the total amount of carbon sputtered from the Toroidal Pumped Limiter, are presented. Recent measurements carried out at high input power show a good agreement with the database used to establish the scaling law.

  10. On organic soil carbon and CO2

    OpenAIRE

    Bohn, Hinrich L.

    2011-01-01

    Cultivation of virgin lands released about 150 times 1012 kg of carbon as CO2 to the atmosphere during the last 100 years, at rates of 1 to 2 times 1012 kg/yr. These rates exceeded the CO2 evolved from fossil fuel combustion until the mid-1960s. Soil organic carbon, in organic and mineral soils, may play a considerable role in the CO2 cycle and in controlling the CO2 concentration of the atmosphere.DOI: 10.1111/j.2153-3490.1978.tb00863.x

  11. Liquid Carbon Reflectivity at 19 nm

    Directory of Open Access Journals (Sweden)

    Riccardo Mincigrucci

    2015-01-01

    Full Text Available We hereby report on a pump-probe reflectivity experiment conducted on amorphous carbon, using a 780 nm laser as a pump and a 19 nm FEL emission as probe. Measurements were performed at 50 degrees with respect to the surface normal to have an un-pumped reflectivity higher than 0.5%. A sub-10 fs time synchronization error could be obtained exploiting the nearly jitter-free capabilities of FERMI. EUV FEL-based experiments open the way to study the behaviour of a liquid carbon phase being unaffected by plasma screening.

  12. Application of Geant4 simulation for analysis of soil carbon inelastic neutron scattering measurements.

    Science.gov (United States)

    Yakubova, Galina; Kavetskiy, Aleksandr; Prior, Stephen A; Torbert, H Allen

    2016-07-01

    Inelastic neutron scattering (INS) was applied to determine soil carbon content. Due to non-uniform soil carbon depth distribution, the correlation between INS signals with some soil carbon content parameter is not obvious; however, a proportionality between INS signals and average carbon weight percent in ~10cm layer for any carbon depth profile is demonstrated using Monte-Carlo simulation (Geant4). Comparison of INS and dry combustion measurements confirms this conclusion. Thus, INS measurements give the value of this soil carbon parameter. PMID:27124122

  13. Mineral Carbonation Employing Ultramafic Mine Waste

    Science.gov (United States)

    Southam, G.; McCutcheon, J.; Power, I. M.; Harrison, A. L.; Wilson, S. A.; Dipple, G. M.

    2014-12-01

    Carbonate minerals are an important, stable carbon sink being investigated as a strategy to sequester CO2 produced by human activity. A natural playa (Atlin, BC, CAN) that has demonstrated the ability to microbially-accelerate hydromagnesite formation was used as an experimental model. Growth of microbial mats from Atlin, in a 10 m long flow-through bioreactor catalysed hydromagnesite precipitation under 'natural' conditions. To enhance mineral carbonation, chrysotile from the Clinton Creek Asbestos Mine (YT, CAN) was used as a target substrate for sulphuric acid leaching, releasing as much as 94% of the magnesium into solution via chemical weathering. This magnesium-rich 'feedstock' was used to examine the ability of the microbialites to enhance carbonate mineral precipitation using only atmospheric CO2 as the carbon source. The phototrophic consortium catalysed the precipitation of platy hydromagnesite [Mg5(CO3)4(OH)2·4H2O] accompanied by magnesite [MgCO3], aragonite [CaCO3], and minor dypingite [Mg5(CO3)4(OH)2·5H2O]. Scanning Electron Microscopy-Energy Dispersive Spectroscopy indicated that cell exteriors and extracellular polymeric substances (EPS) served as nucleation sites for carbonate precipitation. In many cases, entire cyanobacteria filaments were entombed in magnesium carbonate coatings, which appeared to contain a framework of EPS. Cell coatings were composed of small crystals, which intuitively resulted from rapid crystal nucleation. Excess nutrient addition generated eutrophic conditions in the bioreactor, resulting in the growth of a pellicle that sealed the bioreactor contents from the atmosphere. The resulting anaerobic conditions induced fermentation and subsequent acid generation, which in turn caused a drop in pH to circumneutral values and a reduction in carbonate precipitation. Monitoring of the water chemistry conditions indicated that a high pH (> 9.4), and relatively high concentrations of magnesium (> 3000 ppm), compared with the natural

  14. The formation of carbon nanostructures by in situ TEM mechanical nanoscale fatigue and fracture of carbon thin films

    Energy Technology Data Exchange (ETDEWEB)

    Wang, J J; Lockwood, A J; Peng, Y; Xu, X; Inkson, B J [Department of Engineering Materials, University of Sheffield, Sheffield S1 3JD (United Kingdom); Bobji, M S, E-mail: beverley.inkson@sheffield.ac.u [Department of Mechanical Engineering, Indian Institute of Science, Bangalore 560012, Karnataka (India)

    2009-07-29

    A technique to quantify in real time the microstructural changes occurring during mechanical nanoscale fatigue of ultrathin surface coatings has been developed. Cyclic nanoscale loading, with amplitudes less than 100 nm, is achieved with a mechanical probe miniaturized to fit inside a transmission electron microscope (TEM). The TEM tribological probe can be used for nanofriction and nanofatigue testing, with 3D control of the loading direction and simultaneous TEM imaging of the nano-objects. It is demonstrated that fracture of 10-20 nm thick amorphous carbon films on sharp gold asperities, by a single nanoscale shear impact, results in the formation of <10 nm diameter amorphous carbon filaments. Failure of the same carbon films after cyclic nanofatigue, however, results in the formation of carbon nanostructures with a significant degree of graphitic ordering, including a carbon onion.

  15. Molecular dynamics simulation on mechanical property of carbon nanotube torsional deformation

    Institute of Scientific and Technical Information of China (English)

    Chen Ming-Jun; Liang Ying-Chun; Li Hong-Zhu; Li Dan

    2006-01-01

    In this paper torsional deformation of the carbon nanotubes is simulated by molecular dynamics method. The Brenner potential is used to set up the simulation system. Simulation results show that the carbon nanotubes can bear larger torsional deformation, for the armchair type (10,10) single wall carbon nanotubes, with a yielding phenomenon taking place when the torsional angle is up to 63°(1.1rad). The influence of carbon nanotube helicity in torsional deformation is very small. The shear modulus of single wall carbon nanotubes should be several hundred GPa, not 1 GPa as others reports.

  16. Conformational analysis and electronic structure of chiral carbon and carbon nitride nanotubes

    Directory of Open Access Journals (Sweden)

    Cristiano Geraldo de Faria

    2011-12-01

    Full Text Available Geometry and electronic structure of chiral carbon and carbon nitride (CNx nanotubes were investigated through quantum chemical methods. Finite nanotubes with diameters ranging from 5 to 10 Å and containing up to 500 atoms were considered. CNx structures were built through random substitution of carbon atoms by nitrogen. The molecules were fully optimized by semi-empirical quantum chemical method (PM3. Our results show that the energy associated with nitrogen incorporation depends strongly upon the tube helicity and diameter. The doping of nanotubes with nitrogen contributes to reduce the stress caused by the small diameter of the studied systems. Density of States (DOS results for pure carbon and CNx nanostructures, obtained through DFT and Hartree-Fock calculations, were analyzed. The introduction of nitrogen in the tube produce states in the gap region which characterizes the metallic behavior, as expected for these systems after N-doping.

  17. Carbon nanotubes and carbon onions for modification of styrene-acrylate copolymer based nanocomposites

    Energy Technology Data Exchange (ETDEWEB)

    Merijs-Meri, Remo; Zicans, Janis; Ivanova, Tatjana; Bitenieks, Juris [Institute of Polymer Materials, Riga Technical University, Azenes street 14/24, LV-1048, Riga (Latvia); Kuzhir, Polina; Maksimenko, Sergey [Institute of Nuclear Problems, Belarus State University, Bobruiskaya str. 11, 220030, Minsk (Belarus); Kuznetsov, Vladimir; Moseenkov, Sergey [Boreskov Institute of Catalyst Siberian branch of RAS, pr. Lavrentieva 5, 630090, Novosibirsk (Russian Federation)

    2014-05-15

    Styrene acrylate polymer (SAC) nanocomposites with various carbon nanofillers (multiwalled carbon nanotubes MWCNTs and onion like carbon OLC) are manufactured by means of latex based routes. Concentration of the carbon nanofillers is changed in a broad interval starting from 0.01 up to 10 wt. %. Elastic, dielectric and electromagnetic properties of SAC nanocomposites are investigated. Elastic modulus, electrical conductivity and electromagnetic radiation absorption of the investigated SAC nanocomposites increase along with rising nanofiller content. The effect of the addition of anisometric MWCNTs on the elastic properties of the composite is higher than in the case of the addition of OLC. Higher electrical conductivity of the OLC containing nanocomposites is explained with the fact that reasonable agglomeration of the nanofiller can promote the development of electrically conductive network. Efficiency of the absorption of electromagnetic radiation depends on the development of conductive network within the SAC matrix.

  18. The Ammount of Interstellar Carbon Locked in Solid Hydrogenated Amorphous Carbon

    CERN Document Server

    Furton, D G; Witt, A N

    1999-01-01

    We review the literature and present new experimental data to determine the amount of carbon likely to be locked in form of solid hydrogenated amorphous carbon (HAC) grains. We conclude on the basis of a thorough analysis of the intrinsic strength of the C-H stretching band at 3.4 micron that between 10 and 80 ppM H of carbon is in the form of HAC grains. We show that it is necessary to know the level of hydrogenation (H/C) of the interstellar HAC to determine more precisely the amount of carbon it ties up. We present optical constants, photoluminescence spectroscopy, and IR absorption spectroscopy for a particular HAC sample that is shown to have a 3.4 micron absorption feature that is quantatively consistent with that observed in the diffuse interstellar medium.

  19. Carbon isotope techniques

    International Nuclear Information System (INIS)

    This book is a hands-on introduction to using carbon isotope tracers in experimental biology and ecology. It is a bench-top reference with protocols for the study of plants, animals, and soils. The 11C, 12C, 13C, and 14C carbon isotopes are considered and standard techniques are described by established authors. The compilation includes the following features: specific, well-established, user-oriented techniques; carbon cycles in plants, animals, soils, air, and water; isotopes in ecological research; examples and sample calculations

  20. Legacy effects of grassland management on soil carbon to depth.

    Science.gov (United States)

    Ward, Susan E; Smart, Simon M; Quirk, Helen; Tallowin, Jerry R B; Mortimer, Simon R; Shiel, Robert S; Wilby, Andrew; Bardgett, Richard D

    2016-08-01

    The importance of managing land to optimize carbon sequestration for climate change mitigation is widely recognized, with grasslands being identified as having the potential to sequester additional carbon. However, most soil carbon inventories only consider surface soils, and most large-scale surveys group ecosystems into broad habitats without considering management intensity. Consequently, little is known about the quantity of deep soil carbon and its sensitivity to management. From a nationwide survey of grassland soils to 1 m depth, we show that carbon in grassland soils is vulnerable to management and that these management effects can be detected to considerable depth down the soil profile, albeit at decreasing significance with depth. Carbon concentrations in soil decreased as management intensity increased, but greatest soil carbon stocks (accounting for bulk density differences), were at intermediate levels of management. Our study also highlights the considerable amounts of carbon in subsurface soil below 30 cm, which is missed by standard carbon inventories. We estimate grassland soil carbon in Great Britain to be 2097 Tg C to a depth of 1 m, with ~60% of this carbon being below 30 cm. Total stocks of soil carbon (t ha(-1) ) to 1 m depth were 10.7% greater at intermediate relative to intensive management, which equates to 10.1 t ha(-1) in surface soils (0-30 cm), and 13.7 t ha(-1) in soils from 30 to 100 cm depth. Our findings highlight the existence of substantial carbon stocks at depth in grassland soils that are sensitive to management. This is of high relevance globally, given the extent of land cover and large stocks of carbon held in temperate managed grasslands. Our findings have implications for the future management of grasslands for carbon storage and climate mitigation, and for global carbon models which do not currently account for changes in soil carbon to depth with management. PMID:26854892

  1. Influence of spatial configurations on electromagnetic interference shielding of ordered mesoporous carbon/ordered mesoporous silica/silica composites

    OpenAIRE

    Wang, Jiacheng; Zhou, Hu; Zhuang, Jiandong; Liu, Qian

    2013-01-01

    Ordered mesoporous carbons (OMCs), obtained by nanocasting using ordered mesoporous silicas (OMSs) as hard templates, exhibit unique arrangements of ordered regular nanopore/nanowire mesostructures. Here, we used nanocasting combined with hot-pressing to prepare 10 wt% OMC/OMS/SiO2 ternary composites possessing various carbon mesostructure configurations of different dimensionalities (1D isolated CS41 carbon nanowires, 2D hexagonal CMK-3 carbon, and 3D cubic CMK-1 carbon). The electric/dielec...

  2. Measurement of the activity coefficient of carbon in steels in liquid sodium

    International Nuclear Information System (INIS)

    In sodium cooled fast reactors carbon is both a carbon impurity and element of structural materials. Carbon transfert through liquid sodium can produce carburization or decarburization of structural materials. Carbon content in sodium is determined with thin foils of austenitic alloys, when equilibrium is reached thermodynamic activity of carbon in sodium is deduced from carbon activity in alloys. Studied alloys are FeMn 20%, FeNi 30%, Z2CN 18-10 and Z3CND17-13. Carbon activity of alloys in sodium was between 5.10-3 and 10-1 at 600 and 6500C. Calibration was obtained with the alloys FeNi 30% in gaseous mixtures He-CO-CO2 of known activity

  3. A novel carbon fiber based porous carbon monolith

    Energy Technology Data Exchange (ETDEWEB)

    Burchell, T.D.; Klett, J.W.; Weaver, C.E.

    1995-07-01

    A novel porous carbon material based on carbon fibers has been developed. The material, when activated, develops a significant micro- or mesopore volume dependent upon the carbon fiber type utilized (isotropic pitch or polyacrylonitrile). The materials will find applications in the field of fluid separations or as a catalyst support. Here, the manufacture and characterization of our porous carbon monoliths are described.

  4. The solubility of very low concentratiions of carbon monoxide in aqueous solution

    OpenAIRE

    Meadows, R. W.; Spedding, D. J.

    2011-01-01

    The solubility of carbon monoxide in natural waters has been determined when the partial pressure of carbon monoxide in the gas phase approaches atmospheric concentrations. For both pure water and seawater the solubilities were found to be more than eight times the values which have previously been observed with an atmosphere of pure carbon monoxide present. Carbon monoxide therefore does not obey Henry's law over the pressure range from approximately 10?5 atmospheres to greater than one atmo...

  5. Effect of carbon dioxide concentration on the bioleaching of a pyrite-arsenopyrite ore concentrate

    Energy Technology Data Exchange (ETDEWEB)

    Nagpal, S.; Dahlstrom, D. (Univ. of Utah, Salt Lake City (United States)); Oolman, T. (Radian Corp., Austin, TX (United States))

    1993-02-20

    The effect of carbon dioxide concentration on the bacterial leaching of a pyrite-arsenopyrite ore concentrate was studied in continuous-flow reactors. Steady-state operation with two feed slurry densities, 6 wt% and 16wt% solids, were tested for the effect of carbon dioxide concentration. Bacterial growth rates were estimated via the measurement of carbon dioxide consumption rates. Aqueous-phase carbon dioxide concentrations in excess of 10 mg/L were found to be inhibitory to bacterial growth.

  6. Carbon (EC/OC) concentrations as derived from routine PM measurements in the Netherlands

    Energy Technology Data Exchange (ETDEWEB)

    Ten Brink, H.M.; Weijers, E.P. [ECN Biomass, Coal and Environmental Research, Petten (Netherlands); Van Arkel, F.T. [Netherlands Environmental Assessment Agency PBK, Den Haag (Netherlands); De Jonge, D. [GGD Amsterdam, Amsterdam (Netherlands)

    2009-12-15

    Filter samples, collected in the national BOP programme (Netherlands Research Program on Particulate Matter), were analysed for their carbon content. The average amount of carbon at the six measuring sites corresponded with a mass concentration of 5 {mu}g.m{sup -3} in PM10 and 4 {mu}g.m{sup -3} in PM2.5, showing that carbon is a major component of particulate matter (PM). An important problem was that a substantial part of the carbon was derived from volatile carbon that was adsorbed on the filters. The amount of adsorbed volatile carbon was estimated from the carbon found in unloaded filters. This report first describes the adsorption problem itself, because it is the main reason why a standard method for measuring carbon in PM is lacking. Subsequently is described how the actual amount of carbon in PM was estimated.

  7. Carbon Stock and Carbon Cycle of Wetland Ecosystem

    Institute of Scientific and Technical Information of China (English)

    Zhangquan; ZENG; Canming; ZHANG; Jiao; LI; Nan; YANG; Xihao; LI; Yandong; NIU; Zijian; WU

    2014-01-01

    Wetland ecosystem is an essential ecosystem in the world. Its organic carbon stock and carbon cycle are important basis of global carbon cycle researches and also major contents of global climate change researches. Researches have shown that wetland protection and restoration can promote carbon accumulation and reduce emission of greenhouse gases. This paper discussed influence of carbon stock and carbon balance of wetland ecosystem and emission of greenhouse gases,as well as the relationship between wetland and global climate changes. Finally,it made prospect on researches about carbon cycle of Dongting Lake.

  8. A novel carbon fiber based porous carbon monolith

    Energy Technology Data Exchange (ETDEWEB)

    Burchell, T.D.; Klett, J.W.; Weaver, C.E.

    1995-06-01

    A novel porous carbon material based on carbon fibers has been developed. The material, when activated, develops a significant micro- or mesopore volume dependent upon the carbon fiber type utilized (isotropic pitch or polyacrylonitrile). The materials will find applications in the field of fluid separations or as a catalyst support. Here, the manufacture and characterization of our porous carbon monoliths are described. A novel adsorbent carbon composite material has been developed comprising carbon fibers and a binder. The material, called carbon fiber composite molecular sieve (CFCMS), was developed through a joint research program between Oak Ridge National Laboratory (ORNL) and the University of Kentucky, Center for Applied Energy Research (UKCAER).

  9. Efficient organic carbon burial in the Bengal fan sustained by the Himalayan erosional system.

    Science.gov (United States)

    Galy, Valier; France-Lanord, Christian; Beyssac, Olivier; Faure, Pierre; Kudrass, Hermann; Palhol, Fabien

    2007-11-15

    Continental erosion controls atmospheric carbon dioxide levels on geological timescales through silicate weathering, riverine transport and subsequent burial of organic carbon in oceanic sediments. The efficiency of organic carbon deposition in sedimentary basins is however limited by the organic carbon load capacity of the sediments and organic carbon oxidation in continental margins. At the global scale, previous studies have suggested that about 70 per cent of riverine organic carbon is returned to the atmosphere, such as in the Amazon basin. Here we present a comprehensive organic carbon budget for the Himalayan erosional system, including source rocks, river sediments and marine sediments buried in the Bengal fan. We show that organic carbon export is controlled by sediment properties, and that oxidative loss is negligible during transport and deposition to the ocean. Our results indicate that 70 to 85 per cent of the organic carbon is recent organic matter captured during transport, which serves as a net sink for atmospheric carbon dioxide. The amount of organic carbon deposited in the Bengal basin represents about 10 to 20 per cent of the total terrestrial organic carbon buried in oceanic sediments. High erosion rates in the Himalayas generate high sedimentation rates and low oxygen availability in the Bay of Bengal that sustain the observed extreme organic carbon burial efficiency. Active orogenic systems generate enhanced physical erosion and the resulting organic carbon burial buffers atmospheric carbon dioxide levels, thereby exerting a negative feedback on climate over geological timescales. PMID:18004382

  10. Efeito da adição do melaço na relação carbono/nitrogênio no cultivo de camarão Litopenaeus vannamei na fase berçário - DOI: 10.4025/actascibiolsci.v31i4.4496 Effect of molasses addition on carbon/nitrogen ratio in the nursery phase of Litopenaeus vannamei shrimp culture - DOI: 10.4025/actascibiolsci.v31i4.4496

    Directory of Open Access Journals (Sweden)

    Diogo Bessa Neves Spanghero

    2009-08-01

    Full Text Available Investigou-se o efeito da adição do melaço nas relações carbono:nitrogênio (C:N sobre o desempenho zootécnico do camarão Litopenaeus vannamei, na fase berçário, quando cultivado sem renovação de água. As relações do C:N foram avaliadas nas proporções de 25:1 (25M, 15:1 (15M e o controle (0M, sem aplicação de carbono, em delineamento experimental inteiramente casualizado, com quatro repetições. Pós-larvas (PL com peso inicial de 2,5 ± 0,5 mg, foram estocadas em 12 tanques (800 L volume útil, em densidades de 6,25 PL L-1, durante 42 dias de cultivo. Ao final do cultivo, os pesos finais dos camarões dos tratamentos 25M (532,0 mg e 15M (540,0 mg foram superiores (p L. vannamei cultivadas na fase berçário sem renovação de águaThe effect of molasses addiction on carbon:nitrogen ratios (C:N on the performance of Litopenaeus vannamei shrimp during the nursery phase cultured without water exchange was investigated. The C:N ratios were evaluated in 25:1 (25M and 15:1 (15M proportion and a control (0M, with no carbon source addition, in a randomized experimental design with four replicates. Post-larvae (PL with initial weight of 2.5 ± 0.5 mg were stocked in 12 tanks (800 L net volume, at the density of 6.25 PL L-1 during 42 culture days. At the end of culture, the shrimps weights on 25M (532.0 mg and 15M (540.0 mg treatments were higher (p L. vannamei post-larvae cultured without water exchange.

  11. Dissolved inorganic carbon, total alkalinity, pH, and other variables collected from surface discrete observations using flow through pump and other instruments from M/V Skogafoss in the Northeast U.S. Shelf (off the southern coast of Greenland) and North Atlantic ocean during the Ocean Acidification Cruise SKO1501 from 2015-12-05 to 2015-12-10 (NCEI Accession 0154380)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Increasing amounts of atmospheric carbon dioxide from human industrial activities are causing changes in global ocean carbon chemistry. Through the SOOP program we...

  12. Draw out Carbon Nanotube from Liquid Carbon

    OpenAIRE

    ZHANG, SHUANG; Hoshi, Takeo; Fujiwara, Takeo

    2006-01-01

    Carbon nanotube (CNT) is expected for much more important and broader applications in the future, because of its amazing electrical and mechanical properties. However, today, the prospect is detained by the fact that the growth of CNTs cannot be well controlled. In particular, controlling the chirality of CNTs seems formidable to any existing growth method. In addition, a systematic method for a designed interconnected network has not been established yet, which is focused particularly in nan...

  13. High performance carbon-carbon composites

    Indian Academy of Sciences (India)

    Lalit M Manocha

    2003-02-01

    Carbon-carbon composites rank first among ceramic composite materials with a spectrum of properties and applications in various sectors. These composites are made of fibres in various directions and carbonaceous polymers and hydrocarbons as matrix precursors. Their density and properties depend on the type and volume fraction of reinforcement, matrix precursor used and end heat treatment temperature. Composites made with thermosetting resins as matrix precursors possess low densities (1.55–1.75 g/cm3) and well-distributed microporosity whereas those made with pitch as the matrix precursor, after densification exhibit densities of 1.8–2.0 g/cm3 with some mesopores, and those made by the CVD technique with hydrocarbon gases, possess intermediate densities and matrices with close porosities. The former (resin-based) composites exhibit high flexural strength, low toughness and low thermal conductivity, whereas the latter (pitch- and CVD-based) can be made with very high thermal conductivity (400–700 W/MK) in the fibre direction. Carbon-carbon composites are used in a variety of sectors requiring high mechanical properties at elevated temperatures, good frictional properties for brake pads in high speed vehicles or high thermal conductivity for thermal management applications. However, for extended life applications, these composites need to be protected against oxidation either through matrix modification with Si, Zr, Hf etc. or by multilayer oxidation protection coatings consisting of SiC, silica, zircon etc.

  14. Carbon aerogels; Les aerogels de carbone

    Energy Technology Data Exchange (ETDEWEB)

    Berthon-Fabry, S.; Achard, P

    2003-06-15

    The carbon aerogel is a nano-porous material at open porosity, electrical conductor. The aerogels morphology is variable in function of the different synthesis parameters. This characteristic offers to the aerogels a better adaptability to many applications: electrodes (super condensers, fuel cells). The author presents the materials elaboration and their applications. It provides also the research programs: fundamental research, realization of super-condenser electrodes, fuel cells electrodes, gas storage materials and opaque materials for thermal insulation. (A.L.B.)

  15. Carbon Monoxide Information Center

    Medline Plus

    Full Text Available ... United States die every year from accidental non-fire related CO poisoning. Products that can produce deadly ... Driven Generators, 2004-2014 January 07, 2016 Non-Fire Carbon Monoxide Deaths Associated with the Use of ...

  16. Carbon diffusion in niobium

    International Nuclear Information System (INIS)

    An attempt is made to find out the reasons for deviations in the literary data on carbon diffusion in niobium. Methods of layer-by-layer radiometric analysis and measuring the internal friction are applied for this purpose. It is shown that penetration curves can be presented as a sum of two exponents which describe the distribution of active carbon in the surface and depth layers. Carbon diffusion parameters calculated in the above two regions are noticeably different, which can be the reason for deviations in the literary data. The temperature dependence of carbon diffusion coefficients in niobium at 677-1300 deg C in found which corresponds to the interstitial diffusion coe icient

  17. Carbon monoxide intoxication

    Energy Technology Data Exchange (ETDEWEB)

    Kales, S.N. (Cambridge Hospital, MA (United States))

    1993-11-01

    Carbon monoxide poisoning usually results from inhalation of exhaust fumes from motor vehicles, smoke from fires or fumes from faulty heating systems. Carbon monoxide has a high affinity for hemoglobin, with which it forms carboxyhemoglobin. The resulting decrease in both oxygen-carrying capacity and oxygen release can lead to end-organ hypoxia. The clinical presentation is nonspecific. Headache, dizziness, fatigue and nausea are common in mild to moderate carbon monoxide poisoning. In more severe cases, tachycardia, tachypnea and central nervous system depression occur. When carbon monoxide intoxication is suspected, empiric treatment with 100 percent oxygen should be initiated immediately. The diagnosis is confirmed by documenting an elevated carboxyhemoglobin level. Hyperbaric oxygen therapy is recommended in patients with neurologic dysfunction, cardiac dysfunction or a history of unconsciousness. 26 refs.

  18. 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.

  19. Carbon monoxide poisoning

    Science.gov (United States)

    ... heater). Many carbon monoxide poisonings occur in the winter months when furnaces, gas fireplaces, and portable heaters ... 16567227 www.ncbi.nlm.nih.gov/pubmed/16567227 . Nelson LS, Hoffman RS. Inhaled toxins. In: Marx JA, ...

  20. Total Ecosystem Carbon Stock

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — Total ecosystem carbon includes above- and below-ground live plant components (such as leaf, branch, stem and root), dead biomass (such as standing dead wood, down...

  1. FLUIDIZATION OF CARBON NANOTUBES

    Institute of Scientific and Technical Information of China (English)

    Fei Wei; Cang Huang; Yao Wang

    2005-01-01

    Carbon nanotubes (CNTs) can be fluidized in the form of fluidlike agglomerates made of many three-dimensional sub-agglomerates, having a multi-stage agglomerate (MSA) structure and containing large amounts of twisting CNTs of micrometer magnitude.

  2. Carbon nanotubes: Fibrillar pharmacology

    Science.gov (United States)

    Kostarelos, Kostas

    2010-10-01

    The mechanisms by which chemically functionalized carbon nanotubes flow in blood and are excreted through the kidneys illustrate the unconventional behaviour of these fibrillar nanostructures, and the opportunities they offer as components for the design of advanced delivery vehicles.

  3. Carbon Monoxide Information Center

    Medline Plus

    Full Text Available ... Safety Network Community Outreach Resource Center CO Poster Contest Toy Recall Statistics Pool Safely Home / Safety Education / ... VIDEO CPSC announces winners of carbon monoxide poster contest View the blog SAFETY GUIDE Clues You Can ...

  4. Carbon Monoxide Information Center

    Medline Plus

    Full Text Available ... United States die every year from accidental non-fire related CO poisoning. Products that can produce deadly ... CO Blogs Research & Statistics January 07, 2016 Non-Fire Carbon Monoxide Deaths Associated with the Use of ...

  5. Carbon Monoxide Information Center

    Medline Plus

    Full Text Available ... Safety More CO Blogs Research & Statistics March 09, 2016 Supplemental Memos Regarding Some of the Hazards Associated with Engine-Driven Generators, 2004-2014 January 07, 2016 Non-Fire Carbon Monoxide Deaths Associated with the ...

  6. Carbon Monoxide Information Center

    Medline Plus

    Full Text Available ... Other CO Topics Safety Tips Recalls and News Questions and Answers Charcoal Portable Heaters & Camping Equipment Home Heating Equipment On Safety Blogs: CO Safety More CO Blogs Research & Statistics January 07, 2016 Non-Fire Carbon Monoxide ...

  7. Carbon Monoxide Information Center

    Medline Plus

    Full Text Available ... Import Safety International Recall Guidance Civil and Criminal Penalties Federal Court Orders ... 07, 2016 Non-Fire Carbon Monoxide Deaths Associated with the Use of Consumer Products 2012 ...

  8. Carbon Monoxide Information Center

    Medline Plus

    Full Text Available ... On Safety Blogs: CO Safety More CO Blogs Research & Statistics January 07, 2016 Non-Fire Carbon Monoxide ... Inside CPSC: Recalls Safety Education Regulations, Laws & Standards Research & Statistics Business & Manufacturing Small Business Resources International Newsroom ...

  9. Understanding carbon compensation

    International Nuclear Information System (INIS)

    Today, everyone can compensate its carbon emissions on the Internet in few mouse clicks. But what is the meaning of this compensation? What are the mechanisms of voluntary compensation in the framework of the Kyoto protocol? How to participate to this system and to what organisation a company or an individual can call in to reduce his carbon footprint? Carbon compensation is one of the numerous instruments invented to fight against global warming. When it is not possible to reduce our own emissions, we can compensate them by financing projects allowing to reduce the emissions of another company or collectivity. In this book, the authors answer the questions regarding the mechanisms, implementation and efficiency of carbon compensation. (J.S.)

  10. Carbon Monoxide Information Center

    Medline Plus

    Full Text Available ... Statistics January 07, 2016 Non-Fire Carbon Monoxide Deaths Associated with the Use of Consumer Products 2012 Annual Estimates October 13, 2015 Incidents, Deaths, and In-Depth Investigations Associated with Non-Fire ...

  11. Carbon nanotechnology: health and environmental applications

    Czech Academy of Sciences Publication Activity Database

    Vojs, M.; Behúl, M.; Marton, M.; Michniak, P.; Řeháček, V.; Kromka, Alexander; Staňová, A.; Bandžuchová, L.; Švorc, Ľ.

    Bratislava: Slovenská vákuová spoločnosť, 2013 - (Vojs, M.; Veselý, M.; Vincze, A.), s. 113-114 ISBN 978-80-971179-2-4. [School of Vacuum Technology /16./ (Perspektívne vákuové metódy a technológie. Perspective vacuum methods and technologies). Štrbské Pleso (SK), 10.10.2013-13.10.2013] R&D Projects: GA ČR(CZ) GBP108/12/G108 Institutional support: RVO:68378271 Keywords : carbon * environmental applications * BDDE Subject RIV: EI - Biotechnology ; Bionics

  12. On the quantification of atmospheric carbonate carbon by thermal/optical analysis protocols

    Directory of Open Access Journals (Sweden)

    A. Karanasiou

    2010-11-01

    Full Text Available Carbonaceous species, usually classified into two categories, organic carbon (OC and elemental carbon (EC, constitute an important component of the atmospheric aerosol. Carbonate carbon (CC, or inorganic carbon, another constituent of carbonaceous material, is often not considered in many atmospheric chemistry studies. The reason for this may be its low contribution to fine particle mass in most areas studied, along with the difficulties in its analytical determination in atmospheric aerosols. The objective of this study was the quantification of atmospheric carbonate concentrations using the thermal optical transmittance method (Sunset Laboratory, Inc.. Three different temperature protocols (two modified NIOSH protocols and the EUSAAR-2 protocol were tested on filter samples containing known amounts of CC. Moreover, the performance of the two most widely used protocols across European countries (NIOSH and EUSAAR-2 was also checked on two different instruments namely the semi-continuous OCEC analyzer and the laboratory OCEC analyzer. NIOSH-840 thermal protocol (NIOSH protocol with a maximum temperature of 840 °C in the He-mode can be used for the detection and quantification of atmospheric carbonate concentrations. CC was determined in ambient PM10 and PM2.5 samples From Athens and Barcelona by using the NIOSH-840 thermal protocol. The results confirm that in South European countries CC may constitute a significant fraction of carbonaceous aerosols (~15%, thus it should not be neglected. However, the NIOSH-840 protocol seems to overestimate the OC concentrations when compared to the EUSAAR-2 protocol. The results suggest that during dust episodes, common for the Southern Europe, the analytical laboratories could use the NIOSH-840 protocol as a suitable method for the carbonate determination and manually integrate the sharp peak that appears in the maximum temperature step in the inert mode. Afterwards, carbonate should be

  13. Corelli Consort 10

    Index Scriptorium Estoniae

    2001-01-01

    Concerto Grosso alustab kontserdisarja "Ajaloo ilu - Corelli Consort 10" (kava lk. 32), mis ühendab ajalugu, arhitektuuri ja barokkmuusikat. "Jõulumuusika" kontserdid 29. XII Tartus Pistohlkorsi majas, 30. XII Kadrioru lossis (osaleb Jüri Kuuskemaa).

  14. Carbon Footprint of Thermowood

    OpenAIRE

    Nordlund, Teemu

    2015-01-01

    Purpose of this Bachelor’s Thesis was to evaluate the carbon footprint of thermally modified wood and its manufacturing process and transportation cycle for several different ThermoWood producer. Research included the whole production cycle from harvesting raw wood to ThermoWood transportation in destination area. Carbon dioxide emissions from these areas were determined and calculated for every ThermoWood producer at first hand. Calculations were based on the PAS 2050:2011, which is ...

  15. States and carbon

    International Nuclear Information System (INIS)

    The climate challenge appeals to an unprecedented mutation of our societies. From north to south, all our life styles will have to be changed from dwelling, to transport and feeding. These changes will have sense only at a worldwide scale and will impact our way of development. How can we reduce our energy consumption and greenhouse impact with answering everyone's essential needs at the same time? How can we invent a carbon-free economy in the North and preserve the big socio-economical equilibria at the same time? How can we get rid of poverty in the South without compromising the well-being of the future generations with an increase of CO2 emissions? Such difficulties cannot be overcome without innovations in terms of public policies. This book takes stock of the new possible instruments and policies at the global scale and involving fiscality, standards, investments and social justice. Content: 1 - the carbon threat: a changing climate and energies becoming scarce (the climate threat, an increasing energy insecurity); carbon and modern economy (human greenhouse gas emissions, a carbon-free well-being); governments and carbon control (a global challenge requiring an international control, the experiments era from Rio to the present day, the challenge of the state in front of the carbon threat); 2 - the political instruments of environment: standards as first instruments of climate public policies (standards efficiency in some sectors, standards limitations, standards and innovation); emissions quotas and market instruments (Kyoto protocol and CO2 market, the future of 'cap and trade' and of individual and regional quotas); carbon tax, fiscal instruments and new regulations (carbon tax as an alternative or a complement, other fiscal and para-fiscal instruments, new regulation instruments); investing in climate (managing the transition, governments as transition administrators). (J.S)

  16. Hybrid solar cell on a carbon fiber.

    Science.gov (United States)

    Grynko, Dmytro A; Fedoryak, Alexander N; Smertenko, Petro S; Dimitriev, Oleg P; Ogurtsov, Nikolay A; Pud, Alexander A

    2016-12-01

    In this work, a method to assemble nanoscale hybrid solar cells in the form of a brush of radially oriented CdS nanowire crystals around a single carbon fiber is demonstrated for the first time. A solar cell was assembled on a carbon fiber with a diameter of ~5-10 μm which served as a core electrode; inorganic CdS nanowire crystals and organic dye or polymer layers were successively deposited on the carbon fiber as active components resulting in a core-shell photovoltaic structure. Polymer, dye-sensitized, and inverted solar cells have been prepared and compared with their analogues made on the flat indium-tin oxide electrode. PMID:27216603

  17. Double layer capacitance of carbon foam electrodes

    Science.gov (United States)

    Delnick, F. M.; Ingersoll, D.; Firsich, D.

    We have evaluated a wide variety of microcellular carbon foams prepared by the controlled pyrolysis and carbonization of several polymers including: polyacrylonitrile (PAN), polymethacrylonitrile (PMAN), resorcinol/formaldehyde (RF), divinylbenzene/methacrylonitrile (DVB), phenolics (furfuryl/alcohol), and cellulose polymers such as Rayon. The porosity may be established by several processes including: gelation (1-5), phase separation (1-3,5-8), emulsion (1,9,10), aerogel/xerogel formation (1,11,12,13), replication (14), and activation. In this report we present the complex impedance analysis and double layer charging characteristics of electrodes prepared from one of these materials for double layer capacitor applications, namely activated cellulose derived microcellular carbon foam.

  18. Isotope toolbox turns 10

    DEFF Research Database (Denmark)

    Wenander, Fredrik; Riisager, Karsten

    2012-01-01

    REX-ISOLDE, one of CERN’s most compact accelerators, has just celebrated its 10th anniversary. The machine’s versatility provides radioactive ion beams across the range of nuclear isotopes.......REX-ISOLDE, one of CERN’s most compact accelerators, has just celebrated its 10th anniversary. The machine’s versatility provides radioactive ion beams across the range of nuclear isotopes....

  19. 78 FR 46521 - Approval and Promulgation of Air Quality Implementation Plans; State of Colorado; Second 10-Year...

    Science.gov (United States)

    2013-08-01

    ... for the Colorado Springs area for the carbon monoxide (CO) National Ambient Air Quality Standard... Subjects in 40 CFR Part 52 Environmental protection, Air pollution control, Carbon monoxide, Incorporation...; Second 10-Year Carbon Monoxide Maintenance Plan for Colorado Springs AGENCY: Environmental...

  20. 78 FR 56164 - Approval and Promulgation of Air Quality Implementation Plans; State of Colorado; Second 10-Year...

    Science.gov (United States)

    2013-09-12

    ... for the Fort Collins area for the carbon monoxide (CO) National Ambient Air Quality Standard (NAAQS... CFR Part 52 Environmental protection, Air pollution control, Carbon monoxide, Incorporation by...; Second 10-Year Carbon Monoxide Maintenance Plan for Fort Collins AGENCY: Environmental Protection...

  1. Al current collector surface treatment and carbon nano tubes influences on Carbon / Carbon super-capacitors performances

    Energy Technology Data Exchange (ETDEWEB)

    Portet, C.; Taberna, P.L.; Simon, P. [Universite Paul Sabatier, CIRIMAT-LCMIE, 31 - Toulouse (France)

    2004-07-01

    Performances of 4 cm{sup 2} carbon/carbon super-capacitors cells using Al current collectors foils in organic electrolyte are presented; the improvement of electrode material has been investigated. In a first part, a surface treatment of the Al current collector is proposed in order to improve contact surface between the current collector and the active material leading to an internal resistance decrease. The process consists in an etching of the Al foil and is followed by a carbonaceous sol-gel deposit. Galvano-static cycling and Electrochemical Impedance Spectroscopy measurements of super-capacitors all assembled with treated Al foil were tested over 10,000 cycles: an ESR of 0.5 {omega} cm{sup 2} and a capacitance of 95 F g{sup -1} of activated carbon are obtained and performances remain stable during cycling. The second part is devoted to the study of Carbon Nano Tubes (CNTs) adding into the active material on the performances of super-capacitors. A content of 15% of CNTs appears to be the best composition; the ESR is 0.4 {omega} cm{sup 2} (20% lowered as compared to a cell using activated carbon based electrode) and the capacitance remain high 93 F g{sup -1} of carbonaceous active material. (authors)

  2. Carbon based prosthetic devices

    Energy Technology Data Exchange (ETDEWEB)

    Devlin, D.J.; Carroll, D.W.; Barbero, R.S.; Archuleta, T. [Los Alamos National Lab., NM (US); Klawitter, J.J.; Ogilvie, W.; Strzepa, P. [Ascension Orthopedics (US); Cook, S.D. [Tulane Univ., New Orleans, LA (US). School of Medicine

    1998-12-31

    This is the final report of a one-year, Laboratory Directed Research and Development (LDRD) project at the Los Alamos National Laboratory (LANL). The project objective was to evaluate the use of carbon/carbon-fiber-reinforced composites for use in endoprosthetic devices. The application of these materials for the metacarpophalangeal (MP) joints of the hand was investigated. Issues concerning mechanical properties, bone fixation, biocompatibility, and wear are discussed. A system consisting of fiber reinforced materials with a pyrolytic carbon matrix and diamond-like, carbon-coated wear surfaces was developed. Processes were developed for the chemical vapor infiltration (CVI) of pyrolytic carbon into porous fiber preforms with the ability to tailor the outer porosity of the device to provide a surface for bone in-growth. A method for coating diamond-like carbon (DLC) on the articulating surface by plasma-assisted chemical vapor deposition (CVD) was developed. Preliminary results on mechanical properties of the composite system are discussed and initial biocompatibility studies were performed.

  3. Hydrogen adsorption in doped porous carbons

    International Nuclear Information System (INIS)

    Full text of publication follows: Hydrogen is a clean fuel that will be used in automotive transport when the problem of storage will be solved. The difficulties of H2 storage (available space, security and performance, etc...) require a material that can store 5 weight % of hydrogen. Research is focused on new materials that can assume the constraints imposed by the automotive applications. Among these materials, the nano-structured carbons (nano-fibers and single walled carbon nano-tubes) were claimed to be promising by numerous authors [1-3]. The more promising carbon materials for hydrogen adsorption are those having micropores (i. e. single walled carbon nano-tubes and activated carbon), for which the energy of sorption of hydrogen molecules is theoretically higher [7-8]. Presently, the best performance of hydrogen adsorption was found in super-activated microporous carbons sorbing 5 weight % at 77 K, and almost 0.5 % at room temperature and 6 MPa [9]. Up to now, the performance of these materials can still be improved as the known mechanism of sorption in these carbon materials: physi-sorption controlled by Van der Waals attractive forces through London interaction is efficient at cryogenic temperatures (77 K) where the interaction between adsorbent and adsorbate becomes stronger. One way to improve the attractive interaction between adsorbent and molecule is to increase the forces due to the interaction of electrical field and induced dipole of the molecule. This can be theoretically tailored in carbon materials through the electron charge transfer by electron donors who can provide an increase in the electrical field at the surface of the adsorbent. Then, the doping of carbon substrates, appearing to be a promising method to increase the energy of adsorption has been proposed in recent papers as a solution to obtain good hydrogen adsorption properties at appropriate temperatures close to room temperatures [10-12]. Thus, we have studied the adsorption

  4. Black carbon in marine sediments

    NARCIS (Netherlands)

    Middelburg, J.J.; Nieuwenhuize, J.; Van Breugel, P.

    1999-01-01

    Concentrations of black carbon were determined for a number of marine sediments. A comparison of black carbon based on thermal oxidation and hot concentrated nitric acid pretreatments revealed that the latter significantly overestimates combustion derived carbon phases. Black carbon accounts for abo

  5. Nano-Carbons as Theranostics

    Directory of Open Access Journals (Sweden)

    Zhuang Liu, Xing-Jie Liang

    2012-01-01

    Full Text Available Nano-carbons, including fullerenes, carbon nanoparticles, carbon nanotubes, graphene, and nano-diamonds, are an important class of nanostructures attracting tremendous interests in the past two decades. In this special issue, seven review articles and research reports are collected, to summarize and present the latest progress in the exploration of various nano-carbons for theranostic applications.

  6. A study on the carbon-based sorbents injection for gas phase mercury removal from flue gas

    Energy Technology Data Exchange (ETDEWEB)

    Lee, S.; Rhim, Y.; Kim, S.; Park, Y. (and others) [Korea Institute of Energy Research, Daejoen (Republic of Korea). Clean Energy Research Department

    2003-07-01

    To develop carbon-based sorbents to be used in gas-phase mercury removal, the performance of virgin activated carbons (AC) and that of chemically treated activated carbons were compared. Virgin activated carbons (ACs) were made of bituminous coal, lignite, anthracite and NSH4X10. Chemical treated ACs used were those impregnated with sulphuric acid, nitric acid, 1% sulfur, and with mixed sulphuric and nitric acid. Pre-oxidation of activated carbons with acids was also investigated and adsorption performances were compared. Injection of activated carbons has been investigated and the influential factors such as temperature, carbon dose were also discussed. 5 refs., 4 figs., 2 tabs.

  7. [Flue gas desulfurization by a novel biomass activated carbon].

    Science.gov (United States)

    Liu, Jie-Ling; Tang, Zheng-Guang; Chen, Jie; Jiang, Wen-Ju; Jiang, Xia

    2013-04-01

    A novel biomass columnar activated carbon was prepared from walnut shell and pyrolusite was added as a catalyst. The activated carbon prepared was used for flue gas desulphurization in a fixed-bed reactor with 16 g of activated carbon. The impact of operating parameters such as SO2 inlet concentration, space velocity, bed temperature, moisture content and O2 concentration on the desulfurization efficiency of activated carbon was investigated. The results showed that both the breakthrough sulfur capacity and breakthrough time of activated carbon decreased with the increase of SO2 inlet concentration within the range of 0.1% -0.3%. The breakthrough sulfur capacity deceased with the increase of space velocity, with optimal space velocity of 600 h(-1). The optimal bed temperature was 80 degrees C, and the desulfurization efficiency can be reduced if the temperature continue to increase. The presence of moisture and oxygen greatly promoted the adsorption of SO2 onto the activated carbon. The best moisture content was 10%. When the oxygen concentrations were between 10% and 13%, the desulfurization performance of activated carbon was the highest. Under the optimal operating conditions, the sulfur capacity of activated carbon was 252 mg x g(-1), and the breakthrough time was up to 26 h when the SO2 inlet concentration was 0.2%. PMID:23798152

  8. Magnetic properties of pelagic marine carbonates

    Science.gov (United States)

    Roberts, Andrew P.; Florindo, Fabio; Chang, Liao; Heslop, David; Jovane, Luigi; Larrasoaña, Juan C.

    2013-12-01

    Pelagic carbonates are deposited far from continents, usually at water depths of 3000-6000 m, at rates below 10 cm/kyr, and are a globally important sediment type. Recent advances, with recognition of widespread preservation of biogenic magnetite (the inorganic remains of magnetotactic bacteria), have fundamentally changed our understanding of the magnetic properties of pelagic carbonates. We review evidence for the magnetic minerals typically preserved in pelagic carbonates, the effects of magnetic mineral diagenesis on paleomagnetic and environmental magnetic records of pelagic carbonates, and what magnetic properties can tell us about the open-ocean environments in which pelagic carbonates are deposited. We also discuss briefly late diagenetic remagnetisations recorded by some carbonates. Despite recent advances in our knowledge of these phenomena, much remains undiscovered. We are only at early stages of understanding how biogenic magnetite gives rise to paleomagnetic signals in sediments and whether it carries a poorly understood biogeochemical remanent magnetisation. Recently developed techniques have potential for testing how different magnetotactic bacterial species, which produce different magnetite morphologies, respond to changing nutrient and oxygenation conditions. Future work needs to test whether it is possible to develop proxies for ancient nutrient conditions from well-calibrated modern magnetotactic bacterial occurrences. A tantalizing link between giant magnetofossils and Paleogene hyperthermal events needs to be tested; much remains to be learned about the relationship between climate and the organisms that biomineralised these large and novel magnetite morphologies. Rather than being a well-worn subject that has been studied for over 60 years, the magnetic properties of pelagic carbonates hold many secrets that await discovery.

  9. Novel apparatus for joining of carbon-carbon composites

    Science.gov (United States)

    White, Jeremiah D. E.; Mukasyan, Alexander S.; La Forest, Mark L.; Simpson, Allen H.

    2007-01-01

    A novel apparatus for joining carbon-carbon (C-C) composites is presented. This device was designed and built based on the concept of self-sustained oxygen-free high-temperature reactions. A layer of reactive mixture is contained between two disks of C-C composite that are to be joined. The stack is held in place between two electrodes, which are connected to a dc power supply. dc current is used to uniformly initiate the reaction in the reactive layer. The electrodes are also part of the pneumatic system, which applies a load to the stack. The designed hydraulic system is effective, lending to low cost and simplified, rapid, accurate operation. It provides a very short response time (˜10ms), which is important for the considered applications. All operational parameters such as initial and final loads, applied current, delay time between ignition and final load application, duration of Joule heating, and safety interlocks are controlled by a programable logic controller system. These features make it an efficient, user-friendly and safe machine to join refractory materials. The entire joining process takes place on the order of seconds, rather than hours as required for solid-state joining methods. The mechanical properties of the obtained joints are higher than those for the C-C composites.

  10. The uncertainty of modeled soil carbon stock change for Finland

    Science.gov (United States)

    Lehtonen, Aleksi; Heikkinen, Juha

    2013-04-01

    Countries should report soil carbon stock changes of forests for Kyoto Protocol. Under Kyoto Protocol one can omit reporting of a carbon pool by verifying that the pool is not a source of carbon, which is especially tempting for the soil pool. However, verifying that soils of a nation are not a source of carbon in given year seems to be nearly impossible. The Yasso07 model was parametrized against various decomposition data using MCMC method. Soil carbon change in Finland between 1972 and 2011 were simulated with Yasso07 model using litter input data derived from the National Forest Inventory (NFI) and fellings time series. The uncertainties of biomass models, litter turnoverrates, NFI sampling and Yasso07 model were propagated with Monte Carlo simulations. Due to biomass estimation methods, uncertainties of various litter input sources (e.g. living trees, natural mortality and fellings) correlate strongly between each other. We show how original covariance matrices can be analytically combined and the amount of simulated components reduce greatly. While doing simulations we found that proper handling correlations may be even more essential than accurate estimates of standard errors. As a preliminary results, from the analysis we found that both Southern- and Northern Finland were soil carbon sinks, coefficient of variations (CV) varying 10%-25% when model was driven with long term constant weather data. When we applied annual weather data, soils were both sinks and sources of carbon and CVs varied from 10%-90%. This implies that the success of soil carbon sink verification depends on the weather data applied with models. Due to this fact IPCC should provide clear guidance for the weather data applied with soil carbon models and also for soil carbon sink verification. In the UNFCCC reporting carbon sinks of forest biomass have been typically averaged for five years - similar period for soil model weather data would be logical.

  11. Thermophysical properties of composite materials based on high-molecular compounds with fibrous filler between 10 and 400 K

    International Nuclear Information System (INIS)

    The thermophysical properties of glass, carbon, and glass-carbon fibers are examined, and it is noted that the properties of glass fibers increase monotonically with increasing temperature. The behavior of carbon-fiber thermal diffusivity along and across the fibers is found to be anomalous, especially at temperatures between 50 and 200 K. Attention is given to the study of the properties of glass-carbon fibers on the basis of epoxy resin EDT-10 with modifying additives as well as of the filler composed of carbon and glass-fiber ropes in a temperature range of 10 to 400 K

  12. Climate policy and dependence on traded carbon

    Science.gov (United States)

    Andrew, Robbie M.; Davis, Steven J.; Peters, Glen P.

    2013-09-01

    A growing number of countries regulate carbon dioxide (CO2) emissions occurring within their borders, but due to rapid growth in international trade, the products consumed in many of the same countries increasingly rely on coal, oil and gas extracted and burned in other countries where CO2 is not regulated. As a consequence, existing national and regional climate policies may be growing less effective every year. Furthermore, countries that are dependent on imported products or fossil fuels are more exposed to energy and climate policies in other countries. We show that the combined international trade in carbon (as fossil fuels and also embodied in products) increased from 12.3 GtCO2 (55% of global emissions) in 1997 to 17.6 GtCO2 (60%) in 2007 (growing at 3.7% yr-1). Within this, trade in fossil fuels was larger (10.8 GtCO2 in 2007) than trade in embodied carbon (6.9 GtCO2), but the latter grew faster (4.6% yr-1 compared with 3.1% yr-1 for fuels). Most major economies demonstrate increased dependence on traded carbon, either as exports or as imports. Because energy is increasingly embodied in internationally traded products, both as fossil fuels and as products, energy and climate policies in other countries may weaken domestic climate policy via carbon leakage and mask energy security issues.

  13. Production of activated carbons from almond shell

    Energy Technology Data Exchange (ETDEWEB)

    Nabais, Joao M. Valente; Laginhas, Carlos Eduardo C.; Carrott, P.J.M.; Ribeiro Carrott, M.M.L. [Evora Univ. (Portugal). Centro de Quimica de Evora

    2011-02-15

    The production of activated carbons from almond shell, using physical activation by CO{sub 2} is reported in this work. The used method has produced activated carbons with apparent BET surface areas and micropore volume as high as 1138 m{sup 2} g{sup -1} and 0.49 cm{sup 3} g{sup -1}, respectively. The activated carbons produced have essentially primary micropores and only a small volume of wider micropores. By FTIR analysis it was possible to identify, in the surface of the activated carbons, several functional groups, namely hydroxyls (free and phenol), ethers, esters, lactones, pyrones and Si-H bonds. By the analysis of the XRD patterns it was possible to calculate the microcrystallites dimensions with height between 1.178 and 1.881 nm and width between 3.106 and 5.917 nm. From the XRD it was also possible to identify the presence of traces of inorganic heteroatoms such as Si, Pb, K, Fe and P. All activated carbons showed basic characteristics with point of zero charge between 9.42 and 10.43. (author)

  14. Carbon trading: time for industry involvement

    International Nuclear Information System (INIS)

    Carbon trading is no longer just theory. Infant markets already exist and, in 2002, they traded perhaps $10 million worth of emissions allowances. We estimate conservatively that, by 2010, the EU scheme will trade as much as $1 billion in allowances each year. The motor of the carbon markets is a worldwide effort to reduce emissions of greenhouse gases. Its most visible symbol is the Kyoto Protocol of 1997, formally known as the United Nations Framework Convention on Climate Change. Even if Kyoto is not ratified and, despite the US's decision to opt out of the treaty, the genie of greenhouse-gas reduction is out of the bottle. We believe that trading of greenhouse gases will be a real, day-to-day activity by 2010, almost certainly in Europe and probably in Canada and Japan. Carbon trading in these areas will affect the US, whether or not America sets up a programme of its own. The conclusion of this study is that industry should get involved in defining carbon trading - and now - to advance and defend their interests. Interest should be greatest among producers and users of the greenhouse gases other than carbon dioxide, namely methane, nitrous oxide, hydrofluorocarbons, perfluorocarbons and sulphur hexafluoride. (author)

  15. Organic modification of carbon nanotubes

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    The organic modification of carbon nanotubes is a novel research field being developed recently. In this article, the history and newest progress of organic modification of carbon nanotubes are reviewed from two aspects:organic covalent modification and organic noncovalent modification of carbon nanotubes. The preparation and properties of organic modified carbon nanotubes are discussed in detail. In addition, the prospective development of organic modification of carbon nanotubes is suggested.

  16. Understanding Geochemical Impacts of Carbon Dioxide Leakage from Carbon Capture and Sequestration

    Science.gov (United States)

    US EPA held a technical Geochemical Impact Workshop in Washington, DC on July 10 and 11, 2007 to discuss geological considerations and Area of Review (AoR) issues related to geologic sequestration (GS) of Carbon Dioxide (CO2). Seventy=one (71) representatives of the electric uti...

  17. Radiation effect on martensitic hardenable steel 03Cr10Ni--10Mo(TiAl)

    International Nuclear Information System (INIS)

    Radiation reduces notch toughness, increases strength characteristics and reduces plasticity. The chemical composition of 03Cr10Ni10Mo2 steel, mainly the effect of carbon, silicon and titanium cause changes in the radiation stability of various melts. The melt no.2 showed better notch toughness than the no.1. The regeneration annealing of irradiated samples showed the possibility of the regeneration of radiation damage. The strength characteristics are reduced, plasticity is increased. The resulting radiation hardening in the melt no.1 is also reduced for both irradiation temperatures (124 and 350 degC). (B.S.)

  18. On Carbon Burning in Super Asymptotic Giant Branch Stars

    CERN Document Server

    Farmer, R; Timmes, F X

    2015-01-01

    We explore the detailed and broad properties of carbon burning in Super Asymptotic Giant Branch (SAGB) stars with 2755 MESA stellar evolution models. The location of first carbon ignition, quenching location of the carbon burning flames and flashes, angular frequency of the carbon core, and carbon core mass are studied as a function of the ZAMS mass, initial rotation rate, and mixing parameters such as convective overshoot, semiconvection, thermohaline and angular momentum transport. In general terms, we find these properties of carbon burning in SAGB models are not a strong function of the initial rotation profile, but are a sensitive function of the overshoot parameter. We quasi-analytically derive an approximate ignition density, $\\rho_{ign} \\approx 2.1 \\times 10^6$ g cm$^{-3}$, to predict the location of first carbon ignition in models that ignite carbon off-center. We also find that overshoot moves the ZAMS mass boundaries where off-center carbon ignition occurs at a nearly uniform rate of $\\Delta M_{\\rm...

  19. Estimation of soil organic carbon reservoir in China

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    The paper respectively adopted physio-chemical properties of every soil stratum from 2473 soil profiles of the second national soil survey. The corresponding carbon content of soils is estimated by utilizing conversion coefficient 0.58. In the second soil survey, the total amount of soil organic carbon is about 924.18×108t and carbon density is about 10.53 kgC/m2 in China according to the area of 877.63×106 hm2 surveyed throughout the country. The spatial distribution characteristics of soil organic carbon in China is that the carbon storage increases when latitude increases in eastern China and the carbon storage decreases when longitude reduces in northern China. A transitional zone with great variation in carbon storage exists. Moreover, there is an increasing tendency of carbon density with decrease of latitude in western China. Soil circle is of great significance to global change, but with substantial difference in soil spatial distribution throughout the country. Because the structure of soil is inhomogeneous, it could bring some mistakes in estimating soil carbon reservoirs. It is necessary to farther resolve soil respiration and organic matter conversion and other questions by developing uniform and normal methods of measurement and sampling.

  20. THE Eucalyptus sp. AGE PLANTATIONS INFLUENCING THE CARBON STOCKS

    Directory of Open Access Journals (Sweden)

    Charlote Wink

    2013-06-01

    Full Text Available http://dx.doi.org/10.5902/198050989279The tree growth and biomass accumulation, as well as the maintenance of forest residue at the soil surface can act in the removal of carbon from the atmosphere through the cycling process of plant material. The objective was to study the influence of Eucalyptus sp. Plantations with 20, 44 and 240 months of age on the variation of carbon in soil and biomass. The carbon in the soil depth was determined by CHNS auto-analyzer and carbon in the vegetation was determined by the biomass in each forest, considering a factor of 0.45 of the dry mass. We determined the density and particle size distribution of soil. For the comparison between plantations, there was analysis of variance and comparison of means of carbon in vegetation and soil, considering the 5% level of probability. The carbon content and stock in the soil were low, indicating that a natural feature of the category of Paleuldt, or the growth of eucalyptus forests, replacing the field native vegetation did not aggregate a significant increase in the carbon. Although, there was a significant increase carbon in aboveground biomass. It includes forest biomass and litter. So, despite the values ​​of carbon stocks are low, it identified a greater average total in the soil compared to the stock aboveground. Furthermore, this increase aboveground (tree and litter compartments can be considered significant between the eucalyptus plantations of different ages.

  1. 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,...

  2. Carbon foam/hydroxyapatite coating for carbon/carbon composites: Microstructure and biocompatibility

    International Nuclear Information System (INIS)

    To improve the surface biocompatibility of carbon/carbon composites, a carbon foam/hydroxyapatite coating was applied using a combination method of slurry procedure and ultrasound-assisted electrochemical deposition procedure. The morphology, microstructure and chemical composition of the coating were investigated by scanning electron microscopy, energy dispersive X-ray spectroscopy, Fourier transform infrared spectroscopy, Raman spectroscopy and X-ray diffraction. The biocompatibility of the carbon foam/hydroxyapatite coating was investigated by osteoblast-like MG63 cell culture tests. The results showed that the carbon foam could provide a large number of pores on the surface of carbon/carbon composites. The hydroxyapatite crystals could infiltrate into the pores and form the carbon foam/hydroxyapatite coating. The coating covered the carbon/carbon composites fully and uniformly with slice morphology. The cell response tests showed that the MG63 cells on carbon foam/hydroxyapatite coating had a better cell adhesion and cell proliferation than those on uncoated carbon/carbon composites. The carbon foam/hydroxyapatite coatings were cytocompatible and were beneficial to improve the biocompatibility. The approach presented here may be exploited for fabrication of carbon/carbon composite implant surfaces.

  3. Possible mediators for modification of carbon substrate based electodes for construction of biosensors

    Czech Academy of Sciences Publication Activity Database

    Kotzian, P.; Brázdilová, P.; Bartoš, M.; Beyene, N. W.; Švancara, I.; Vlček, Milan; Kalcher, K.; Vytřas, K.

    Galway : National University of Ireland , 2004. s. 149. [International Conference on Electoanalysis /10./. 06.06.2004-10.06.2004, Galway] Keywords : carbon substrate Subject RIV: CA - Inorganic Chemistry

  4. Carbon nanotubes decorating methods

    Directory of Open Access Journals (Sweden)

    A.D. Dobrzańska-Danikiewicz

    2013-06-01

    Full Text Available Purpose: The work is to present and characterise various methods of depositing carbon nanotubes with nanoparticles of precious metals, and also to present the results of own works concerning carbon nanotubes coated with platinum nanoparticles.Design/methodology/approach: Electron transmission and scanning microscopy has been used for imaging the structure and morphology of the nanocomposites obtained and the distribution of nanoparticles on the surface of carbon nanotubes.Findings: The studies carried out with the HRTEM and SEM techniques have confirmed differences in morphology, homogeneity and density of depositing platinum nanoparticles on the surface of carbon nanotubes and its structure.Research limitations/implications: The studies conducted pertained to the process of decorating carbon nanotubes with platinum nanoparticles. Further works are planned aimed at extending the application scope of the newly developed methodology to include the methods of nanotubes decorating with the nanoparticles of other precious metals (mainly palladium and rhodium.Practical implications: CNTs-NPs (Carbon NanoTube-NanoParticles composites can be used as the active elements of sensors featuring high sensitivity, fast action, high selectivity and accuracy, in particular in medicine as cholesterol and glucoses sensors; in the automotive industry for the precision monitoring of working parameters in individual engine components; in environmental conservation to examine CO2, NOx, and CH4 concentrations and for checking leak-tightness and detecting hazardous substances in household and industrial gas installations.Originality/value: The comprehensive characterisation of the methods employed for fabricating nanocomposites consisting of carbon nanotubes deposited with Pt, Pd, Rh, Au, Ag nanoparticles with special consideration to the colloidal process.

  5. Big Sky Carbon Sequestration Partnership

    Energy Technology Data Exchange (ETDEWEB)

    Susan Capalbo

    2005-12-31

    The Big Sky Carbon Sequestration Partnership, led by Montana State University, is comprised of research institutions, public entities and private sectors organizations, and the Confederated Salish and Kootenai Tribes and the Nez Perce Tribe. Efforts under this Partnership in Phase I are organized into four areas: (1) Evaluation of sources and carbon sequestration sinks that will be used to determine the location of pilot demonstrations in Phase II; (2) Development of GIS-based reporting framework that links with national networks; (3) Design of an integrated suite of monitoring, measuring, and verification technologies, market-based opportunities for carbon management, and an economic/risk assessment framework; (referred to below as the Advanced Concepts component of the Phase I efforts) and (4) Initiation of a comprehensive education and outreach program. As a result of the Phase I activities, the groundwork is in place to provide an assessment of storage capabilities for CO{sub 2} utilizing the resources found in the Partnership region (both geological and terrestrial sinks), that complements the ongoing DOE research agenda in Carbon Sequestration. The geology of the Big Sky Carbon Sequestration Partnership Region is favorable for the potential sequestration of enormous volume of CO{sub 2}. The United States Geological Survey (USGS 1995) identified 10 geologic provinces and 111 plays in the region. These provinces and plays include both sedimentary rock types characteristic of oil, gas, and coal productions as well as large areas of mafic volcanic rocks. Of the 10 provinces and 111 plays, 1 province and 4 plays are located within Idaho. The remaining 9 provinces and 107 plays are dominated by sedimentary rocks and located in the states of Montana and Wyoming. The potential sequestration capacity of the 9 sedimentary provinces within the region ranges from 25,000 to almost 900,000 million metric tons of CO{sub 2}. Overall every sedimentary formation investigated

  6. Windows 10 Technical Preview

    OpenAIRE

    Jyväsjärvi, Teppo

    2015-01-01

    Tässä opinnäytetyössä tutustaan uuden kesällä 2015 virallisesti julkaistavan Windows 10 -käyttöjärjestelmän Technical Preview -kehitysversioon. Ensimmäinen Technical Preview -versio julkaistiin syksyllä 2014. Opinnäytetyössä tutustaan Windows 10:n uusin ominaisuuksiin ja tehdään vertailua aiemman Windows 8.1 -version kanssa. Työssä Windows 10 Technical Preview asennetaan virtuaalikoneelle, käydään läpi asennuksen eri vaiheet sekä suurimmat muutokset käyttöliittymässä ja sovelluksissa. Op...

  7. Electroprecipitation of potassium americyl carbonate from potassium carbonate solutions

    International Nuclear Information System (INIS)

    Precipitation of potassium americyl carbonate was carried out at multigram scale by oxidizing americium(III) at the platinum anode in 3M K2CO3 solutions. Early investigations were conducted on pure americium 241 solutions on the 10 to 40 mg scale, in order to study the different parameters of the electrolysis, and to prove the feasibility of the process. Further experiments were performed on the 20 g scale, in impure americium 241 solutions. Electrolysis performed at 600C with a platinum grid as the anode, and a tantalum rod immersed in a cathodic compartment, precipitated 20 g of americium 241 with yields above 99% in 2 h. The electroprecipitation process presents the advantage of being clean and suitable for automation techniques in comparison with the chemical oxidation process using potassium persulphate. (orig.)

  8. Electroprecipitation of potassium americyl carbonate from potassium carbonate solutions

    International Nuclear Information System (INIS)

    Precipitation of potassium americyl carbonate was carried out at multigram scale by oxidizing at platinum anode Am(III) in 3 M K2CO3 solutions. Early investigations were conducted on pure americium 241 solutions on 10 to 40 mg scale, in order to study the different parameters of the electrolysis, and to prove the faisability of the process. Further experiments have been performed on the 20 grams scale, in impure americium 241 solutions. Electrolysis performed at 600C with platinum grid as anode, and tantalum rod immersed in a cathodic compartment, precipitates 20 grams of americium 241 with yields above 99% in two hours. The electroprecipitation process presents the advantage to be clean and suitable for automation technique in comparison with the chemical oxidation process using potassium persulfate

  9. Measurement of carbon capture efficiency and stored carbon leakage

    Science.gov (United States)

    Keeling, Ralph F.; Dubey, Manvendra K.

    2013-01-29

    Data representative of a measured carbon dioxide (CO.sub.2) concentration and of a measured oxygen (O.sub.2) concentration at a measurement location can be used to determine whether the measured carbon dioxide concentration at the measurement location is elevated relative to a baseline carbon dioxide concentration due to escape of carbon dioxide from a source associated with a carbon capture and storage process. Optionally, the data can be used to quantify a carbon dioxide concentration increase at the first location that is attributable to escape of carbon dioxide from the source and to calculate a rate of escape of carbon dioxide from the source by executing a model of gas-phase transport using at least the first carbon dioxide concentration increase. Related systems, methods, and articles of manufacture are also described.

  10. Microbially mediated carbon mineralization: Geoengineering a carbon-neutral mine

    Science.gov (United States)

    Power, I. M.; McCutcheon, J.; Harrison, A. L.; Wilson, S. A.; Dipple, G. M.; Southam, G.

    2013-12-01

    Ultramafic and mafic mine tailings are a potentially valuable feedstock for carbon mineralization, affording the mining industry an opportunity to completely offset their carbon emissions. Passive carbon mineralization has previously been documented at the abandoned Clinton Creek asbestos mine, and the active Diavik diamond mine and Mount Keith nickel mine, yet the majority of tailings remain unreacted. Examples of microbe-carbonate interactions at each mine suggest that biological pathways could be harnessed to promote carbon mineralization. In suitable environmental conditions, microbes can mediate geochemical processes to accelerate mineral dissolution, increase the supply of carbon dioxide (CO2), and induce carbonate precipitation, all of which may accelerate carbon mineralization. Tailings mineralogy and the availability of a CO2 point source are key considerations in designing tailings storage facilities (TSF) for optimizing carbon mineralization. We evaluate the efficacy of acceleration strategies including bioleaching, biologically induced carbonate precipitation, and heterotrophic oxidation of waste organics, as well as abiotic strategies including enhancing passive carbonation through modifying tailings management practices and use of CO2 point sources (Fig. 1). With the aim of developing carbon-neutral mines, implementation of carbon mineralization strategies into TSF design will be driven by economic incentives and public pressure for environmental sustainability in the mining industry. Figure 1. Schematic illustrating geoengineered scenarios for carbon mineralization of ultramafic mine tailings. Scenarios A and B are based on non-point and point sources of CO2, respectively.

  11. Carbon nanotube core graphitic shell hybrid fibers.

    Science.gov (United States)

    Hahm, Myung Gwan; Lee, Jae-Hwang; Hart, Amelia H C; Song, Sung Moo; Nam, Jaewook; Jung, Hyun Young; Hashim, Daniel Paul; Li, Bo; Narayanan, Tharangattu N; Park, Chi-Dong; Zhao, Yao; Vajtai, Robert; Kim, Yoong Ahm; Hayashi, Takuya; Ku, Bon-Cheol; Endo, Morinobu; Barrera, Enrique; Jung, Yung Joon; Thomas, Edwin L; Ajayan, Pulickel M

    2013-12-23

    A carbon nanotube yarn core graphitic shell hybrid fiber was fabricated via facile heat treatment of epoxy-based negative photoresist (SU-8) on carbon nanotube yarn. The effective encapsulation of carbon nanotube yarn in carbon fiber and a glassy carbon outer shell determines their physical properties. The higher electrical conductivity (than carbon fiber) of the carbon nanotube yarn overcomes the drawbacks of carbon fiber/glassy carbon, and the better properties (than carbon nanotubes) of the carbon fiber/glassy carbon make up for the lower thermal and mechanical properties of the carbon nanotube yarn via synergistic hybridization without any chemical doping and additional processes. PMID:24224730

  12. Selective Oxidation of Soft Grade Carbon

    Directory of Open Access Journals (Sweden)

    Zecevic, N.

    2007-12-01

    the surface area is essential. Mutual oxidizing agents are ozone, air, mixture of nitric oxide and air, and nitric acid. However, treatment with highly oxidizing agents in a gaseous phase or aqueous medium may highly increase the concentration of acid oxides on the surface area of the carbon black. Acid oxides on the surface area of carbon black decrease the pH value, which is closely connected to the vulcanization of rubber compounds. Furthermore, the afore-mentioned method has other disadvantages. In the case of nitrate acid, the major disadvantage is corrosion of plant equipment. The mixture of nitrite oxide and air demands a very complicated plant, and the same procedure is very time consuming. Ozone increases the oxygen content on the surface area of the carbon black by as much as 15 %, which creates carbon dioxide and reduces utilization. Air creates thermally unstable surface area oxides, since the process demands a temperature range between 450 and 700 °C. Due to all these reasons, an oxidation method was developed of eliminating non-reacted oil from the surface area of oil-furnace carbon black, which cannot be produced with the conventional production method. An aqueous solution of salt ammonium nitrate p.a. proved to be a very good oxidizing agent. Conventional soft grades of oil-furnace carbon blacks with very high contents of non-reacted oil on their surface area, were mixed with the appropriate mass weight of ammonium nitrate p. a. (1.25 to 10.00 g L-1 NH4NO3 p. a.. The obtained homogeneous mixture was dried at temperatures from 180 to 210 °C for a period of 30 to 120 min. Namely, oil-furnace carbon blacks are first produced in a "fluffy" form with exceptionally small mass density, which is why they are very unpractical for manipulation. The "fluffy" oil-furnace carbon black must be transformed to a greater weight density and have a smaller quantity of fines as possible. However, there are many industrial processes of transforming "fluffy" carbon black

  13. Hydrogen adsorption in doped porous carbons

    International Nuclear Information System (INIS)

    Full text of publication follows: Hydrogen is a clean fuel that will be used in automotive transport when the problem of storage will be solved. The difficulties of H2 storage (available space, security and performance, etc...) require a material that can store 5 weight % of hydrogen. Research is focused on new materials that can assume the constraints imposed by the automotive applications. Among these materials, the nano-structured carbons (nano-fibers and single walled carbon nano-tubes) were claimed to be promising by numerous authors [1-3]. The more promising carbon materials for hydrogen adsorption are those having micropores (i. e. single walled carbon nano-tubes and activated carbon), for which the energy of sorption of hydrogen molecules is theoretically higher [7- 8]. Presently, the best performance of hydrogen adsorption was found in super-activated micro-porous carbons sorbing 5 weight % at 77 K, and almost 0.5 % at room temperature and 6 MPa [9]. Up to now, the performance of these materials can still be improved as the known mechanism of sorption in these carbon materials: physisorption controlled by Van der Waals attractive forces through London interaction is efficient at cryogenic temperatures (77 K) where the interaction between adsorbent and adsorbate becomes stronger. One way to improve the attractive interaction between adsorbent and molecule is to increase the forces due to the interaction of electrical field and induced dipole of the molecule. This can be theoretically tailored in carbon materials through the electron charge transfer by electron donors who can provide an increase in the electrical field al the surface of the adsorbent. Then, the doping of carbon substrates, appearing to be a promising method to increase the energy of adsorption has been proposed in recent papers as a solution to obtain good hydrogen adsorption properties at appropriate temperatures close to room temperatures [10-12]. Thus, we have studied the adsorption

  14. Anthropogenic perturbation of the carbon fluxes from land to ocean

    KAUST Repository

    Regnier, Pierre

    2013-06-09

    A substantial amount of the atmospheric carbon taken up on land through photosynthesis and chemical weathering is transported laterally along the aquatic continuum from upland terrestrial ecosystems to the ocean. So far, global carbon budget estimates have implicitly assumed that the transformation and lateral transport of carbon along this aquatic continuum has remained unchanged since pre-industrial times. A synthesis of published work reveals the magnitude of present-day lateral carbon fluxes from land to ocean, and the extent to which human activities have altered these fluxes. We show that anthropogenic perturbation may have increased the flux of carbon to inland waters by as much as 1.0 Pg C yr -1 since pre-industrial times, mainly owing to enhanced carbon export from soils. Most of this additional carbon input to upstream rivers is either emitted back to the atmosphere as carbon dioxide (∼0.4 Pg C yr -1) or sequestered in sediments (∼0.5 Pg C yr -1) along the continuum of freshwater bodies, estuaries and coastal waters, leaving only a perturbation carbon input of ∼0.1 Pg C yr -1 to the open ocean. According to our analysis, terrestrial ecosystems store ∼0.9 Pg C yr -1 at present, which is in agreement with results from forest inventories but significantly differs from the figure of 1.5 Pg C yr -1 previously estimated when ignoring changes in lateral carbon fluxes. We suggest that carbon fluxes along the land-ocean aquatic continuum need to be included in global carbon dioxide budgets.

  15. Beneficial Use of Carbon Dioxide in Precast Concrete Production

    Energy Technology Data Exchange (ETDEWEB)

    Shao, Yixin [McGill Univ., Montreal, QC (Canada)

    2014-06-26

    The feasibility of using carbon dioxide as feedstock in precast concrete production is studied. Carbon dioxide reacts with calcium compounds in concrete, producing solid calcium carbonates in binding matrix. Two typical precast products are examined for their capacity to store carbon dioxide during the production. They are concrete blocks and fiber-cement panels. The two products are currently mass produced and cured by steam. Carbon dioxide can be used to replace steam in curing process to accelerate early strength, improve the long-term durability and reduce energy and emission. For a reaction within a 24-hour process window, the theoretical maximum possible carbon uptake in concrete is found to be 29% based on cement mass in the product. To reach the maximum uptake, a special process is developed to promote the reaction efficiency to 60-80% in 4-hour carbon dioxide curing and improve the resistance to freeze-thaw cycling and sulfate ion attack. The process is also optimized to meet the project target of $10/tCO2 in carbon utilization. By the use of self-concentrating absorption technology, high purity CO2 can be produced at a price below $40/t. With low cost CO2 capture and utilization technologies, it is feasible to establish a network for carbon capture and utilization at the vicinity of carbon sources. If all block produces and panel producers in United States could adopt carbon dioxide process in their production in place of steam, carbon utilization in these two markets alone could consume more than 2 Mt CO2/year. This capture and utilization process can be extended to more precast products and will continue for years to come.

  16. 48 CFR 225.7011 - Restriction on carbon, alloy, and armor steel plate.

    Science.gov (United States)

    2010-10-01

    ... 48 Federal Acquisition Regulations System 3 2010-10-01 2010-10-01 false Restriction on carbon, alloy, and armor steel plate. 225.7011 Section 225.7011 Federal Acquisition Regulations System DEFENSE... on carbon, alloy, and armor steel plate....

  17. 75 FR 56556 - Certain Magnesia Carbon Bricks From China and Mexico

    Science.gov (United States)

    2010-09-16

    ... Register of April 23, 2010 (75 FR 21346). The hearing was held in Washington, DC, on July 27, 2010, and all... COMMISSION Certain Magnesia Carbon Bricks From China and Mexico Determinations On the basis of the record \\1... from China and Mexico of certain magnesia carbon bricks, provided for in subheadings 6902.10.10,...

  18. Investigating effectiveness of activated carbons of natural sources on various supercapacitors

    Science.gov (United States)

    Faisal, Md. Shahnewaz Sabit; Rahman, Muhammad M.; Asmatulu, Ramazan

    2016-04-01

    Activated carbon can be produced from natural sources, such as pistachio and acorn shells, which can be an inexpensive and sustainable sources of natural wastes for the energy storage devices, such as supercapacitors. The carbonaceous materials used in this study were carbonized at the temperatures of 700°C and 900°C after the stabilization process at 240°C for two hours. These shells showed approximately 60% carbon yield. Carbonized nutshells were chemically activated using1wt% potassium hydroxide (KOH). Activated carbon powders with polyvinylidene fluoride (PVdF) were used to construct carbon electrodes. A 1M of tetraethylammonium tetrafluoroborate (TEABF4) and propylene carbonate (PC) were used as electrolytes. Electrochemical techniques, such as cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) were used for the characterization of the supercapacitors. Scanning electron microscopy (SEM) was used to inspect the surface texture of the activated carbons. Activated pistachio shells carbonized at 700°C showed more porous surface texture than those carbonized at 900°C. Effects of the carbonization temperatures were studied for their electrochemical characteristics. The shells carbonized at 700°C showed better electrochemical characteristics compared to those carbonized at 900°C. The test results provided about 27,083 μF/g specific capacitance at a scan rate of 10mV/s. This study showed promising results for using these activated carbons produced from the natural wastes for supercapacitor applications.

  19. Composite electrodes of activated carbon derived from cassava peel and carbon nanotubes for supercapacitor applications

    Science.gov (United States)

    Taer, E.; Iwantono, Yulita, M.; Taslim, R.; Subagio, A.; Salomo, Deraman, M.

    2013-09-01

    In this paper, a composite electrode was prepared from a mixture of activated carbon derived from precarbonization of cassava peel (CP) and carbon nanotubes (CNTs). The activated carbon was produced by pyrolysis process using ZnCl2 as an activation agent. A N2 adsorption-desorption analysis for the sample indicated that the BET surface area of the activated carbon was 1336 m2 g-1. Difference percentage of CNTs of 0, 5, 10, 15 and 20% with 5% of PVDF binder were added into CP based activated carbon in order to fabricate the composite electrodes. The morphology and structure of the composite electrodes were investigated by scanning electron microscopy (SEM) and X-ray diffraction (XRD) techniques. The SEM image observed that the distribution of CNTs was homogeneous between carbon particles and the XRD pattern shown the amorphous structure of the sample. The electrodes were fabricated for supercapacitor cells with 316L stainless steel as current collector and 1 M sulfuric acid as electrolyte. An electrochemical characterization was performed by using an electrochemical impedance spectroscopy (EIS) method using a Solatron 1286 instrument and the addition of CNTs revealed to improve the resistant and capacitive properties of supercapacitor cell.

  20. Incentives of carbon dioxide regulation for investment in low-carbon electricity technologies in Texas

    International Nuclear Information System (INIS)

    This paper compares the incentives a carbon dioxide emissions price creates for investment in low carbon dioxide-emitting technologies in the electricity sector. We consider the extent to which operational differences across generation technologies - particularly, nuclear, wind and solar photovoltaic - create differences in the incentives for new investment, which is measured by the operating profits of a potential entrant. First, astylized model of an electricity system demonstrates that the composition of the existing generation system may cause electricity prices to increase by different amounts over time when a carbon dioxide price is imposed. Differences in operation across technologies therefore translate to differences in the operating profits of a potential entrant. Then, a detailed simulation model is used to consider a hypothetical carbon dioxide price of $10-$50 per metric ton for the Electric Reliability Council of Texas (ERCOT) market. The simulations show that, for the range of prices considered, the increase in electricity prices is positively correlated with output from a typical wind unit, but the correlation is much weaker for nuclear and photovoltaic. Consequently, a carbon dioxide price creates much stronger investment incentives for wind than for nuclear or photovoltaic technologies in the Texas market. - Highlights: → Compare incentives for new investment in low-emission electricity technologies created by carbon dioxide price. → Focus on ERCOT power system using stochastic unit commitment model. →Find a greater incentive for wind than solar or nuclear because of correlation between wind generation and increase in electricity prices.

  1. Carbon Concentration of Austenite

    Directory of Open Access Journals (Sweden)

    Z. Ławrynowicz

    2007-07-01

    Full Text Available The investigation was carried out to examine the influence of temperature and times of austempering process on the maximum extend towhich the bainite reaction can proceed and the carbon content in retained austenite. It should be noted that a small percentage change in theaustenite carbon content can have a significant effect on the subsequent austempering reaction changing the volume fraction of the phasespresent and hence, the resulting mechanical properties. Specimens were prepared from an unalloyed ductile cast iron, austenitised at 950oCfor 60 minutes and austempered by the conventional single-step austempering process at four temperatures between BS and MS, eg., 250,300, 350 and 400oC. The samples were austempered at these temperatures for 15, 30, 60, 120 and 240 minutes and finally quenched toambient temperature. Volume fractions of retained austenite and carbon concentration in the residual austenite have been observed byusing X-ray diffraction. Additionally, carbon concentration in the residual austenite was calculated using volume fraction data of austeniteand a model developed by Bhadeshia based on the McLellan and Dunn quasi-chemical thermodynamic model. The comparison ofexperimental data with the T0, T0' and Ae3' phase boundaries suggests the likely mechanism of bainite reaction in cast iron is displacive rather than diffusional. The carbon concentration in retained austenite demonstrates that at the end of bainite reaction the microstructure must consist of not only ausferrite but additionally precipitated carbides.

  2. STRING v10

    DEFF Research Database (Denmark)

    Szklarczyk, Damian; Franceschini, Andrea; Wyder, Stefan;

    2015-01-01

    families at various levels of phylogenetic resolution. Further improvements in version 10.0 include a completely redesigned prediction pipeline for inferring protein-protein associations from co-expression data, an API interface for the R computing environment and improved statistical analysis for...... enrichment tests in user-provided networks....

  3. IDEA papers no 10

    International Nuclear Information System (INIS)

    The Information network on the Economic Development in Aquitaine (IDEA) aims to collect and spread the environmental information concerning the Aquitaine, in order to implement an observatory of the regional environment and of the sustainable development. The IDEA paper no.10 is devoted to the sustainable development education. Examples of actions in agriculture schools and colleges are presented. (A.L.B.)

  4. 10 Reasons to Flip

    Science.gov (United States)

    Fulton, Kathleen P.

    2012-01-01

    A small school in southern Minnesota, strapped for funds and needing new math books and a fresh curriculum, flipped its classrooms and raised achievement and student engagement. The math teachers led and implemented the changes. Upon reflection, they found 10 good reasons educators should consider flipping their classroom. Among the most…

  5. UR10 Performance Analysis

    DEFF Research Database (Denmark)

    Ravn, Ole; Andersen, Nils Axel; Andersen, Thomas Timm

    While working with the UR-10 robot arm, it has become apparent that some commands have undesired behaviour when operating the robot arm through a socket connection, sending one command at a time. This report is a collection of the results optained when testing the performance of the different...

  6. Carbon fuel particles used in direct carbon conversion fuel cells

    Science.gov (United States)

    Cooper, John F.; Cherepy, Nerine

    2012-10-09

    A system for preparing particulate carbon fuel and using the particulate carbon fuel in a fuel cell. Carbon particles are finely divided. The finely dividing carbon particles are introduced into the fuel cell. A gas containing oxygen is introduced into the fuel cell. The finely divided carbon particles are exposed to carbonate salts, or to molten NaOH or KOH or LiOH or mixtures of NaOH or KOH or LiOH, or to mixed hydroxides, or to alkali and alkaline earth nitrates.

  7. 从炭材料到低碳社会——2012世界炭会议介绍%How will carbon material lead to a low carbon society——A review of Carbon 2012

    Institute of Scientific and Technical Information of China (English)

    刘旭光

    2012-01-01

    A review is given of the Annual World Conference on Carbon, which was held on June 17-22, 2012 in Krakow, Poland and organized by the Polish Carbon Society. In this conference, 5 plenary lectures, 30 keynote lectures, 220 oral presentations and 465 posters were divided into 10 topics, i. e. , carbons for energy storage ; carbons for health and environmental protection; precursors, processing and technology; carbon nanomate-rials; porous carbons; carbon-based composites; graphene; new methods for carbon characterization; computation and modeling; and industrial news. Besides traditional modification on surface area and porosity, doping with hetero atoms such as N, B and P or compositing with metals or metal oxides have been developed into effective means for modifying carbon materials for improved adsorption, catalysis and energy-storage performance. The applications of novel carbon structures like nanotubes are still limited by the controllable and scalable preparation, processability and reactivity. Research on the structure and properties of graphene is moving from curiosity-oriented to application-oriented. Mathematical formulation or modeling of pore structures has been promoted by the progress in characterization methods. The modification of the surface/interface in carbon materials, which plays important roles in determining their physical, chemical or mechanical properties is still a focus of research activity in carbon materials.

  8. Preparation of (10R,S)-[10-3H] juvenile hormone III and (10R,S, 11S,R)-[10-3H] juvenile hormone O; conversion of [10-3H] juvenile hormone III to methyl (2E,6E)-[10-3H] farnesoate and (2E,6E)-[10-3H] farnesol

    International Nuclear Information System (INIS)

    Samples of racemic [10-3H]juvenile hormone III (methyl (2E,6E)-10,11 epoxy-3,7,11-trimethyl-2,6-dodecadienoate) and [10-3H]juvenile hormone 0 (methyl (2E,6E, 10cis)-3,7-diethyl-10,11-epoxy-11-methyl-2, 6-tridecadienoate) were prepared by NaB3H4 reduction of the corresponding 11-chloro-10-oxo ('chloroketone') precursors to their respective [10-3H] chlorohydrins, followed by treatment of the latter with potassium carbonate in methanol. [10-3H] Juvenile hormone III was converted to methyl [10-3H]farnesoate (methyl (2E,6E)-3,7,11-trimethyl-2,6,10-dodecatrienoate) by reduction with sodium iodide and zinc in acetic acid-sodium acetate. Further reduction of methyl [10-3H]farnesoate with diisobutyl aluminum hydride afforded a sample of [10-3H]farnesol ((2E, 6E)-3,7,11-trimethyl-2,6,10-dodecatrien-1-o1). (author)

  9. Iron-Doped Carbon Aerogels: Novel Porous Substrates for Direct Growth of Carbon Nanotubes

    Science.gov (United States)

    Steiner, S. A.; Baumann, T. F.; Kong, J.; Satcher, J. H.; Dresselhaus, M. S.

    2007-02-20

    We present the synthesis and characterization of Fe-doped carbon aerogels (CAs) and demonstrate the ability to grow carbon nanotubes directly on monoliths of these materials to afford novel carbon aerogel-carbon nanotube composites. Preparation of the Fe-doped CAs begins with the sol-gel polymerization of the potassium salt of 2,4-dihydroxybenzoic acid with formaldehyde, affording K{sup +}-doped gels that can then be converted to Fe{sup 2+}- or Fe{sup 3+}-doped gels through an ion exchange process, dried with supercritical CO{sub 2} and subsequently carbonized under an inert atmosphere. Analysis of the Fe-doped CAs by TEM, XRD and XPS revealed that the doped iron species are reduced during carbonization to form metallic iron and iron carbide nanoparticles. The sizes and chemical composition of the reduced Fe species were related to pyrolysis temperature as well as the type of iron salt used in the ion exchange process. Raman spectroscopy and XRD analysis further reveal that, despite the presence of the Fe species, the CA framework is not significantly graphitized during pyrolysis. The Fe-doped CAs were subsequently placed in a thermal CVD reactor and exposed to a mixture of CH{sub 4} (1000 sccm), H{sub 2} (500 sccm), and C{sub 2}H{sub 4} (20 sccm) at temperatures ranging from 600 to 800 C for 10 minutes, resulting in direct growth of carbon nanotubes on the aerogel monoliths. Carbon nanotubes grown by this method appear to be multiwalled ({approx}25 nm in diameter and up to 4 mm long) and grow through a tip-growth mechanism that pushes catalytic iron particles out of the aerogel framework. The highest yield of CNTs were grown on Fe-doped CAs pyrolyzed at 800 C treated at CVD temperatures of 700 C.

  10. Investigating carbonate formation in urban soils as a method for capture and storage of atmospheric carbon.

    Science.gov (United States)

    Washbourne, C-L; Renforth, P; Manning, D A C

    2012-08-01

    This paper investigates the potential for engineered urban soils to capture and store atmospheric carbon (C). Calcium (Ca) and magnesium (Mg) bearing waste silicate minerals within the soil environment can capture and store atmospheric C through the process of weathering and secondary carbonate mineral precipitation. Anthropogenic soils, known to contain substantial quantities of Ca and Mg-rich minerals derived from demolition activity (particularly cement and concrete), were systematically sampled at the surface across a 10 ha brownfield site, Science Central, located in the urban centre of Newcastle upon Tyne, U.K. Subsequent analysis yielded average carbonate contents of 21.8±4.7% wt CaCO(3). Isotopic analysis demonstrated δ(18)O values between -9.4‰ and -13.3‰ and δ(13)C values between -7.4‰ and -13.6‰ (relative to Pee Dee Belemnite), suggesting that up to 39.4±8.8% of the carbonate C has been captured from the atmosphere through hydroxylation of dissolved CO(2) in high pH solutions. The remaining carbonate C is derived from lithogenic sources. 37.4 kg of atmospheric CO(2) has already been captured and stored as carbonate per Mg of soil across the site, representing a carbon dioxide (CO(2)) removal rate of 12.5 kg CO(2) Mg(-1) yr(-1). There is the potential for capture and storage of a further 27.3 kg CO(2) Mg(-1) in residual reactive materials, which may be exploited through increased residence time (additional in situ weathering). Overall, the Science Central site has the potential to capture and store a total of 64,800 Mg CO(2) as carbonate minerals. This study illustrates the potential for managing urban soils as tools of C capture and storage, an important ecosystem service, and demonstrates the importance of studying C storage in engineering urban anthropogenic soils. PMID:22683756

  11. An Effective Method of Producing Small Neutral Carbon Clusters

    Institute of Scientific and Technical Information of China (English)

    XIA Zhu-Hong; CHEN Cheng-Chu; HSU Yen-Chu

    2007-01-01

    An effective method of producing small neutral carbon clusters Cn (n = 1-6) is described. The small carbon clusters (positive or negative charge or neutral) are formed by plasma which are produced by a high power 532nm pulse laser ablating the surface of the metal Mn rod to react with small hydrocarbons supplied by a pulse valve, then the neutral carbon clusters are extracted and photo-ionized by another laser (266nm or 355nm) in the ionization region of a linear time-of-flight mass spectrometer. The distributions of the initial neutral carbon clusters are analysed with the ionic species appeared in mass spectra. It is observed that the yield of small carbon clusters with the present method is about 10 times than that of the traditional widely used technology of laser vaporization of graphite.

  12. Preparation of Magnesium Carbonate Whisker from Magnesite Tailings

    Energy Technology Data Exchange (ETDEWEB)

    Wang, N; Chen, M [School of Materials and Metallurgy, Northeastern University, Shenyang 110004 (China); Ni, H W, E-mail: chenm@smm.neu.edu.cn [Wuhan University of Science and Technology, Wuhan 430081 (China)

    2011-10-29

    Magnesium carbonate whisker was prepared by thermal decomposition of Mg(HCO{sub 3}){sub 2} solution that was prepared through hydration and carbonation of light burnt magnesia derived from magnesite tailings. The effects of thermal decomposition conditions on the morphology of magnesium carbonate crystal were investigated. The results showed that thermal decomposition product was MgCO{sub 3{center_dot}}3H{sub 2}O, and its crystal morphology was appreciably influenced by the additives added to Mg(HCO{sub 3}){sub 2} solution. Magnesium carbonate whiskers were successfully prepared when a kind of soluble magnesium salt was added, and magnesium carbonate whiskers with the length of 20 to 60{mu}m and aspect ratio of 10{approx}20 were obtained under the condition of 50deg. C thermal decomposition temperature and 200 rpm stirring intensity.

  13. Carbon Cryogel Silicon Composite Anode Materials for Lithium Ion Batteries

    Science.gov (United States)

    Woodworth James; Baldwin, Richard; Bennett, William

    2010-01-01

    A variety of materials are under investigation for use as anode materials in lithium-ion batteries, of which, the most promising are those containing silicon. 10 One such material is a composite formed via the dispersion of silicon in a resorcinol-formaldehyde (RF) gel followed by pyrolysis. Two silicon-carbon composite materials, carbon microspheres and nanofoams produced from nano-phase silicon impregnated RF gel precursors have been synthesized and investigated. Carbon microspheres are produced by forming the silicon-containing RF gel into microspheres whereas carbon nano-foams are produced by impregnating carbon fiber paper with the silicon containing RF gel to create a free standing electrode. 1-4,9 Both materials have demonstrated their ability to function as anodes and utilize the silicon present in the material. Stable reversible capacities above 400 mAh/g for the bulk material and above 1000 mAh/g of Si have been observed.

  14. A preliminary assessment of carbon dioxide mitigation options

    International Nuclear Information System (INIS)

    The purpose of this paper is to place the potential needs to control global carbon dioxide emissions in perspective. In order to limit carbon dioxide levels in the earth's atmosphere to no more than twice pre- anthropogenic levels, it will be necessary to limit carbon emissions to approximately 10 gigatons per year by 2050. The implications of such a constraint to the developed countries, developing countries, and international community are assessed. It is clear that international priorities must be established and specific approaches developed in the first quarter of the 21st century to define the necessary, minimum- cost mitigation strategies. Because of the complexity of establishing a meaningful policy approach, imposition of an arbitrary carbon tax is unlikely to provide the constraints necessary to achieve a satisfactory earth atmosphere - carbon dioxide equilibrium state

  15. Carbon Nanomaterials: Applications in Physico-chemical Systemsand Biosystems

    Directory of Open Access Journals (Sweden)

    Maheshwar Sharon

    2008-07-01

    Full Text Available In the present article, various forms of carbon and carbon nanomaterials (CNMs and a new approach to classify them on the basis of sp2-sp3 configuration are presented. Utilising the concept of junction formation (like p:n junction a concept is developed to explain the special reactivity of nanosized carbon materials. Geometric consideration of chiral and achiral symmetry of single-walled carbon nanotubes is presented which is also responsible for manifesting special propertiesof carbon nanotubes. A brief introduction to various common synthesis techniques of CNMs is given. These is increased chemical and biological activities have resulted in many engineer ednanoparticles, which are being designed for specific purposes, including diagnostic or the rapeuticmedical uses and environmental remediation.Defence Science Journal, 2008, 58(4, pp.460-485, DOI:http://dx.doi.org/10.14429/dsj.58.1668

  16. Atomistic modeling of carbon Cottrell atmospheres in bcc iron

    International Nuclear Information System (INIS)

    Atomistic simulations with an EAM interatomic potential were used to evaluate carbon-dislocation binding energies in bcc iron. These binding energies were then used to calculate the occupation probability of interstitial sites in the vicinity of an edge and a screw dislocation. The saturation concentration due to carbon-carbon interactions was also estimated by atomistic simulations in the dislocation core and taken as an upper limit for carbon concentration in a Cottrell atmosphere. We obtained a maximum concentration of 10 ± 1 at.% C at T = 0 K within a radius of 1 nm from the dislocation lines. The spatial carbon distributions around the line defects revealed that the Cottrell atmosphere associated with an edge dislocation is denser than that around a screw dislocation, in contrast with the predictions of the classical model of Cochardt and colleagues. Moreover, the present Cottrell atmosphere model is in reasonable quantitative accord with the three-dimensional atom probe data available in the literature.

  17. The Carbon Trading Game

    International Nuclear Information System (INIS)

    In response to the Kyoto Protocol, an international market for carbon dioxide tradable permits is likely to be created. Two of the key issues involved are explaining the concepts of tradable permits to industrialists, policy-makers and the man on the street, and anticipating how the market will evolve. A simple game of the market for carbon dioxide tradable permits has been developed and used that can help deal with both issues. As a pedagogical tool, this game benefits from simplicity (just a few pieces of paper are needed) and enables students to grasp the concepts and remember them through the intensity and fun of a trading 'pit'. The experiences also provide substantial insights into the evolution of the carbon dioxide permit market, particularly related to the evolution of trade volume, permit prices and country strategies

  18. Pyrolyzed carbon film diodes.

    Science.gov (United States)

    Morton, Kirstin C; Tokuhisa, Hideo; Baker, Lane A

    2013-11-13

    We have previously reported pyrolyzed parylene C (PPC) as a conductive carbon electrode material for use with micropipets, atomic force microscopy probes, and planar electrodes. Advantages of carbon electrode fabrication from PPC include conformal coating of high-aspect ratio micro/nanoscale features and the benefits afforded by chemical vapor deposition of carbon polymers. In this work, we demonstrate chemical surface doping of PPC through the use of previously reported methods. Chemically treated PPC films are characterized by multiple spectroscopic and electronic measurements. Pyrolyzed parylene C and doped PPC are used to construct diodes that are examined as both p-n heterojunction and Schottky barrier diodes. Half-wave rectification is achieved with PPC diodes and demonstrates the applicability of PPC as a conductive and semiconductive material in device fabrication. PMID:24090451

  19. Carbon Ion Therapy

    DEFF Research Database (Denmark)

    Bassler, Niels; Hansen, David Christoffer; Herrmann, Rochus;

    On the importance of choice of target size for selective boosting of hypoxic tumor subvolumina in carbon ion therapy Purpose: Functional imaging methods in radiotherapy are maturing and can to some extent uncover radio resistant structures found within a tumour entity. Selective boost of identified...... to the surface where the beam enters) are examined. For each plan the minimum,  maximum and the dose averaged LET of the PTV is calculated. The numbers are translated to OER using several sets of data found in literature for various cell lines. Results: We find a strong dependence of the dose average LET and OER...... effect. All cell lines investigated here did not reach an OER of 1, even for the smaller structures, which may indicate that the achievable dose average LET of carbon ions is too low, and heavier ions than carbon may be considered for functional LET-painting....

  20. Carbon Nanotubes for Supercapacitor

    Directory of Open Access Journals (Sweden)

    Li Jianyi

    2010-01-01

    Full Text Available Abstract As an electrical energy storage device, supercapacitor finds attractive applications in consumer electronic products and alternative power source due to its higher energy density, fast discharge/charge time, low level of heating, safety, long-term operation stability, and no disposable parts. This work reviews the recent development of supercapacitor based on carbon nanotubes (CNTs and their composites. The purpose is to give a comprehensive understanding of the advantages and disadvantages of carbon nanotubes-related supercapacitor materials and to find ways for the improvement in the performance of supercapacitor. We first discussed the effects of physical and chemical properties of pure carbon nanotubes, including size, purity, defect, shape, functionalization, and annealing, on the supercapacitance. The composites, including CNTs/oxide and CNTs/polymer, were further discussed to enhance the supercapacitance and keep the stability of the supercapacitor by optimally engineering the composition, particle size, and coverage.