Sample records for optimizing carbon dioxide

  1. Gas Exchange of Algae

    PubMed Central

    Ammann, Elizabeth C. B.; Lynch, Victoria H.

    1967-01-01

    The oxygen production of a photosynthetic gas exchanger containing Chlorella pyrenoidosa (1% packed cell volume) was measured when various concentrations of carbon dioxide were present within the culture unit. The internal carbon dioxide concentrations were obtained by manipulating the entrance gas concentration and the flow rate. Carbon dioxide percentages were monitored by means of electrodes placed directly in the nutrient medium. The concentration of carbon dioxide in the nutrient medium which produced maximal photosynthesis was in the range of 1.5 to 2.5% by volume. Results were unaffected by either the level of carbon dioxide in the entrance gas or the rate of gas flow. Entrance gases containing 2% carbon dioxide flowing at 320 ml/min, 3% carbon dioxide at 135 ml/min, and 4% carbon dioxide at 55 ml/min yielded optimal carbon dioxide concentrations in the particular unit studied. By using carbon dioxide electrodes implanted directly in the gas exchanger to optimize the carbon dioxide concentration throughout the culture medium, it should be possible to design more efficient large-scale units. PMID:4382391

  2. Optimized heat exchange in a CO2 de-sublimation process

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Baxter, Larry; Terrien, Paul; Tessier, Pascal

    The present invention is a process for removing carbon dioxide from a compressed gas stream including cooling the compressed gas in a first heat exchanger, introducing the cooled gas into a de-sublimating heat exchanger, thereby producing a first solid carbon dioxide stream and a first carbon dioxide poor gas stream, expanding the carbon dioxide poor gas stream, thereby producing a second solid carbon dioxide stream and a second carbon dioxide poor gas stream, combining the first solid carbon dioxide stream and the second solid carbon dioxide stream, thereby producing a combined solid carbon dioxide stream, and indirectly exchanging heat betweenmore » the combined solid carbon dioxide stream and the compressed gas in the first heat exchanger.« less

  3. 40 CFR 91.320 - Carbon dioxide analyzer calibration.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... monthly thereafter, or within one month prior to the certification test, calibrate the NDIR carbon dioxide... the analyzer to optimize performance. (2) Zero the carbon dioxide analyzer with either purified synthetic air or zero-grade nitrogen. (3) Calibrate on each normally used operating range with carbon...

  4. Carbon dioxide conversion over carbon-based nanocatalysts.

    PubMed

    Khavarian, Mehrnoush; Chai, Siang-Piao; Mohamed, Abdul Rahman

    2013-07-01

    The utilization of carbon dioxide for the production of valuable chemicals via catalysts is one of the efficient ways to mitigate the greenhouse gases in the atmosphere. It is known that the carbon dioxide conversion and product yields are still low even if the reaction is operated at high pressure and temperature. The carbon dioxide utilization and conversion provides many challenges in exploring new concepts and opportunities for development of unique catalysts for the purpose of activating the carbon dioxide molecules. In this paper, the role of carbon-based nanocatalysts in the hydrogenation of carbon dioxide and direct synthesis of dimethyl carbonate from carbon dioxide and methanol are reviewed. The current catalytic results obtained with different carbon-based nanocatalysts systems are presented and how these materials contribute to the carbon dioxide conversion is explained. In addition, different strategies and preparation methods of nanometallic catalysts on various carbon supports are described to optimize the dispersion of metal nanoparticles and catalytic activity.

  5. 40 CFR 86.524-78 - Carbon dioxide analyzer calibration.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... operation. Adjust the analyzer to optimize performance. (2) Zero the carbon dioxide analyzer with either zero grade air or zero grade nitrogen. (3) Calibrate on each normally used operating range with carbon...

  6. 40 CFR 86.524-78 - Carbon dioxide analyzer calibration.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... operation. Adjust the analyzer to optimize performance. (2) Zero the carbon dioxide analyzer with either zero grade air or zero grade nitrogen. (3) Calibrate on each normally used operating range with carbon...

  7. 40 CFR 86.524-78 - Carbon dioxide analyzer calibration.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... operation. Adjust the analyzer to optimize performance. (2) Zero the carbon dioxide analyzer with either zero grade air or zero grade nitrogen. (3) Calibrate on each normally used operating range with carbon...

  8. Desiccant humidity control system

    NASA Technical Reports Server (NTRS)

    Amazeen, J. (Editor)

    1973-01-01

    A regenerable sorbent system was investigated for controlling the humidity and carbon dioxide concentration of the space shuttle cabin atmosphere. The sorbents considered for water and carbon dioxide removal were silica gel and molecular sieves. Bed optimization and preliminary system design are discussed along with system optimization studies and weight penalites.

  9. An Optimal Centralized Carbon Dioxide Repository for Florida, USA

    PubMed Central

    Poiencot, Brandon; Brown, Christopher

    2011-01-01

    For over a decade, the United States Department of Energy, and engineers, geologists, and scientists from all over the world have investigated the potential for reducing atmospheric carbon emissions through carbon sequestration. Numerous reports exist analyzing the potential for sequestering carbon dioxide at various sites around the globe, but none have identified the potential for a statewide system in Florida, USA. In 2005, 83% of Florida’s electrical energy was produced by natural gas, coal, or oil (e.g., fossil fuels), from power plants spread across the state. In addition, only limited research has been completed on evaluating optimal pipeline transportation networks to centralized carbon dioxide repositories. This paper describes the feasibility and preliminary locations for an optimal centralized Florida-wide carbon sequestration repository. Linear programming optimization modeling is used to plan and route an idealized pipeline network to existing Florida power plants. Further analysis of the subsurface geology in these general locations will provide insight into the suitability of the subsurface conditions and the available capacity for carbon sequestration at selected possible repository sites. The identification of the most favorable site(s) is also presented. PMID:21695024

  10. An optimal centralized carbon dioxide repository for Florida, USA.

    PubMed

    Poiencot, Brandon; Brown, Christopher

    2011-04-01

    For over a decade, the United States Department of Energy, and engineers, geologists, and scientists from all over the world have investigated the potential for reducing atmospheric carbon emissions through carbon sequestration. Numerous reports exist analyzing the potential for sequestering carbon dioxide at various sites around the globe, but none have identified the potential for a statewide system in Florida, USA. In 2005, 83% of Florida's electrical energy was produced by natural gas, coal, or oil (e.g., fossil fuels), from power plants spread across the state. In addition, only limited research has been completed on evaluating optimal pipeline transportation networks to centralized carbon dioxide repositories. This paper describes the feasibility and preliminary locations for an optimal centralized Florida-wide carbon sequestration repository. Linear programming optimization modeling is used to plan and route an idealized pipeline network to existing Florida power plants. Further analysis of the subsurface geology in these general locations will provide insight into the suitability of the subsurface conditions and the available capacity for carbon sequestration at selected possible repository sites. The identification of the most favorable site(s) is also presented.

  11. A carbon dioxide stripping model for mammalian cell culture in manufacturing scale bioreactors.

    PubMed

    Xing, Zizhuo; Lewis, Amanda M; Borys, Michael C; Li, Zheng Jian

    2017-06-01

    Control of carbon dioxide within the optimum range is important in mammalian bioprocesses at the manufacturing scale in order to ensure robust cell growth, high protein yields, and consistent quality attributes. The majority of bioprocess development work is done in laboratory bioreactors, in which carbon dioxide levels are more easily controlled. Some challenges in carbon dioxide control can present themselves when cell culture processes are scaled up, because carbon dioxide accumulation is a common feature due to longer gas-residence time of mammalian cell culture in large scale bioreactors. A carbon dioxide stripping model can be used to better understand and optimize parameters that are critical to cell culture processes at the manufacturing scale. The prevailing carbon dioxide stripping models in literature depend on mass transfer coefficients and were applicable to cell culture processes with low cell density or at stationary/cell death phase. However, it was reported that gas bubbles are saturated with carbon dioxide before leaving the culture, which makes carbon dioxide stripping no longer depend on a mass transfer coefficient in the new generation cell culture processes characterized by longer exponential growth phase, higher peak viable cell densities, and higher specific production rate. Here, we present a new carbon dioxide stripping model for manufacturing scale bioreactors, which is independent of carbon dioxide mass transfer coefficient, but takes into account the gas-residence time and gas CO 2 saturation time. The model was verified by CHO cell culture processes with different peak viable cell densities (7 to 12 × 10 6  cells mL -1 ) for two products in 5,000-L and 25,000-L bioreactors. The model was also applied to a next generation cell culture process to optimize cell culture conditions and reduce carbon dioxide levels at manufacturing scale. The model provides a useful tool to understand and better control cell culture carbon dioxide profiles for process development, scale up, and characterization. Biotechnol. Bioeng. 2017;114: 1184-1194. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  12. 40 CFR 86.1324-84 - Carbon dioxide analyzer calibration.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... Exhaust Test Procedures § 86.1324-84 Carbon dioxide analyzer calibration. Prior to its introduction into...) Follow good engineering practices for instrument start-up and operation. Adjust the analyzer to optimize...

  13. Thermal design of a Mars oxygen production plant

    NASA Technical Reports Server (NTRS)

    Sridhar, K. R.; Iyer, Venkatesh A.

    1991-01-01

    The optimal design of the thermal components of a system that uses carbon dioxide from the Martian atmosphere to produce oxygen for spacecraft propulsion and/or life support is discussed. The gases are pressurized, heated and passed through an electrochemical cell. Carbon dioxide is reduced to carbon monoxide and oxygen due to thermal dissociation and electrocatalysis. The oxygen thus formed is separated from the gas mixture by the electrochemical cell. The objective of the design is to optimize both the overall mass and the power consumption of the system. The analysis shows that at electrochemical cell efficiencies of about 50 percent and lower, the optimal system would require unspent carbon dioxide in the exhaust gases to be separated and recycled. Various methods of efficiently compressing the intake gases to system pressures of 0.1 MPa are investigated. The total power requirement for oxygen production rates of 1, 5, and 10 kg/day at various cell efficiencies are presented.

  14. Apparatus and method for controlling autotroph cultivation

    DOEpatents

    Fuxman, Adrian M; Tixier, Sebastien; Stewart, Gregory E; Haran, Frank M; Backstrom, Johan U; Gerbrandt, Kelsey

    2013-07-02

    A method includes receiving at least one measurement of a dissolved carbon dioxide concentration of a mixture of fluid containing an autotrophic organism. The method also includes determining an adjustment to one or more manipulated variables using the at least one measurement. The method further includes generating one or more signals to modify the one or more manipulated variables based on the determined adjustment. The one or more manipulated variables could include a carbon dioxide flow rate, an air flow rate, a water temperature, and an agitation level for the mixture. At least one model relates the dissolved carbon dioxide concentration to one or more manipulated variables, and the adjustment could be determined by using the at least one model to drive the dissolved carbon dioxide concentration to at least one target that optimize a goal function. The goal function could be to optimize biomass growth rate, nutrient removal and/or lipid production.

  15. Importance of early season conditions and grazing on carbon dioxide fluxes in Colorado shortgrass steppe

    USDA-ARS?s Scientific Manuscript database

    Understanding the influence of environmental and management drivers on fluxes of carbon dioxide (CO2) is essential for optimizing carbon (C) uptake and storage in livestock production systems. Herein, using 15 treatment-years (two three-year experiments, one with three grazing treatments, the other ...

  16. Tuning Organic Carbon Dioxide Absorbents for Carbonation and Decarbonation

    PubMed Central

    Rajamanickam, Ramachandran; Kim, Hyungsoo; Park, Ji-Woong

    2015-01-01

    The reaction of carbon dioxide with a mixture of a superbase and alcohol affords a superbase alkylcarbonate salt via a process that can be reversed at elevated temperatures. To utilize the unique chemistry of superbases for carbon capture technology, it is essential to facilitate carbonation and decarbonation at desired temperatures in an easily controllable manner. Here, we demonstrate that the thermal stabilities of the alkylcarbonate salts of superbases in organic solutions can be tuned by adjusting the compositions of hydroxylic solvent and polar aprotic solvent mixtures, thereby enabling the best possible performances to be obtained from the various carbon dioxide capture agents based on these materials. The findings provides valuable insights into the design and optimization of organic carbon dioxide absorbents. PMID:26033537

  17. Endoscopic Carbon Dioxide Laser Photocoagulation Of Bleeding Canine Gastric Ulcers

    NASA Astrophysics Data System (ADS)

    Gal, Dov; Ron, Nimrod; Orgad, Uri; Katzir, Abraham

    1987-04-01

    This is the first report which describes carbon dioxide laser photocoagulation of upper gastrointestinal bleeding via a flexible endoscope, using an infrared transmitting siver nalide fiber. Various laser parameters were checked to determine the optimal conditions for hemostasis. Both the acute effects of laser irradiation on tissue and the chronic effects on healing process were examined. Preliminary results indicate that carbon dioxide laser beam can successfully photocoagulate moderately bleeding ulcers.

  18. Tethered catalysts for the hydration of carbon dioxide

    DOEpatents

    Valdez, Carlos A; Satcher, Jr., Joe H; Aines, Roger D; Wong, Sergio E; Baker, Sarah E; Lightstone, Felice C; Stolaroff, Joshuah K

    2014-11-04

    A system is provided that substantially increases the efficiency of CO.sub.2 capture and removal by positioning a catalyst within an optimal distance from the air-liquid interface. The catalyst is positioned within the layer determined to be the highest concentration of carbon dioxide. A hydrophobic tether is attached to the catalyst and the hydrophobic tether modulates the position of the catalyst within the liquid layer containing the highest concentration of carbon dioxide.

  19. Aerogel sorbents

    DOEpatents

    Begag, Redouane; Rhine, Wendell E.; Dong, Wenting

    2018-04-03

    The current invention describes methods and compositions of various sorbents based on aerogels of various silanes and their use as sorbent for carbon dioxide. Methods further provide for optimizing the compositions to increase the stability of the sorbents for prolonged use as carbon dioxide capture matrices.

  20. Aerogel sorbents

    DOEpatents

    Begag, Redouane; Rhine, Wendell E; Dong, Wenting

    2016-04-05

    The current invention describes methods and compositions of various sorbents based on aerogels of various silanes and their use as sorbent for carbon dioxide. Methods further provide for optimizing the compositions to increase the stability of the sorbents for prolonged use as carbon dioxide capture matrices.

  1. 40 CFR 90.320 - Carbon dioxide analyzer calibration.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... use and monthly thereafter, or within one month prior to the certification test, calibrate the NDIR... operation. Adjust the analyzer to optimize performance. (2) Zero the carbon dioxide analyzer with either purified synthetic air or zero-grade nitrogen. (3) Calibrate on each normally used operating range with...

  2. High-efficiency and high-power rechargeable lithium–sulfur dioxide batteries exploiting conventional carbonate-based electrolytes

    PubMed Central

    Park, Hyeokjun; Lim, Hee-Dae; Lim, Hyung-Kyu; Seong, Won Mo; Moon, Sehwan; Ko, Youngmin; Lee, Byungju; Bae, Youngjoon; Kim, Hyungjun; Kang, Kisuk

    2017-01-01

    Shedding new light on conventional batteries sometimes inspires a chemistry adoptable for rechargeable batteries. Recently, the primary lithium-sulfur dioxide battery, which offers a high energy density and long shelf-life, is successfully renewed as a promising rechargeable system exhibiting small polarization and good reversibility. Here, we demonstrate for the first time that reversible operation of the lithium-sulfur dioxide battery is also possible by exploiting conventional carbonate-based electrolytes. Theoretical and experimental studies reveal that the sulfur dioxide electrochemistry is highly stable in carbonate-based electrolytes, enabling the reversible formation of lithium dithionite. The use of the carbonate-based electrolyte leads to a remarkable enhancement of power and reversibility; furthermore, the optimized lithium-sulfur dioxide battery with catalysts achieves outstanding cycle stability for over 450 cycles with 0.2 V polarization. This study highlights the potential promise of lithium-sulfur dioxide chemistry along with the viability of conventional carbonate-based electrolytes in metal-gas rechargeable systems. PMID:28492225

  3. Comparison of the Anti-Inflammatory Activities of Supercritical Carbon Dioxide versus Ethanol Extracts from Leaves of Perilla frutescens Britt. Radiation Mutant.

    PubMed

    Jin, Chang Hyun; Park, Han Chul; So, Yangkang; Nam, Bomi; Han, Sung Nim; Kim, Jin-Baek

    2017-02-17

    In this study, we aimed to compare supercritical carbon dioxide extraction and ethanol extraction for isoegomaketone (IK) content in perilla leaf extracts and to identify the optimal method. We measured the IK concentration using HPLC and inflammatory mediators in lipopolysaccharide (LPS)-stimulated RAW 264.7 cells from the extracts. The IK concentration was 10-fold higher in perilla leaf extracts by supercritical carbon dioxide extraction (SFE) compared with that in perilla leaf extracts by ethanol extraction (EE). When the extracts were treated in LPS-induced RAW 264.7 cells at 25 μg/mL, the SFE inhibited the expression of inflammatory mediators such as nitric oxide (NO), monocyte chemoattractant protein-1 (MCP-1), interleutkin-6 (IL-6), interferon-β (IFN-β), and inducible nitric oxide synthase (iNOS) to a much greater extent compared with EE. Taken together, supercritical carbon dioxide extraction is considered the optimal process for obtaining high IK content and anti-inflammatory activities in leaf extracts from the P. frutescens Britt. radiation mutant.

  4. Flotation/ultrasound-assisted microextraction followed by HPLC for determination of fat-soluble vitamins in multivitamin pharmaceutical preparations.

    PubMed

    Shahdousti, Parvin; Aghamohammadi, Mohammad

    2018-04-01

    Dissolved carbon dioxide flotation-emulsification microextraction technique coupled with high-performance liquid chromatography was developed for separation and determination of fat-soluble vitamins (A, D 3 , E, and K 3 ) in multivitamin pharmaceutical preparations. Dissolved carbon dioxide flotation was used to break up the emulsion of extraction solvent in water and to collect the extraction solvent on the surface of aqueous sample in narrowed capillary part of extraction cell. Carbon dioxide bubbles were generated in situ through the addition of 300 μL of concentrated hydrochloric acid into the alkaline sample solution at pH = 11.5 (1% w/v sodium carbonate), which was sonicated to intensify the carbon dioxide bubble generation. Several factors affecting the extraction process were optimized. Under the optimal conditions, the limits of detection were 0.11, 0.47, 0.20 and 0.35 μg/L for A, E, D 3 , and K 3 vitamins in water samples, respectively. The inter-day and intra-day precision of the proposed method were evaluated in terms of the relative standard deviation and were <10.5%. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  5. Development of a low cost unmanned aircraft system for atmospheric carbon dioxide leak detection

    NASA Astrophysics Data System (ADS)

    Mitchell, Taylor Austin

    Carbon sequestration, the storage of carbon dioxide gas underground, has the potential to reduce global warming by removing a greenhouse gas from the atmosphere. These storage sites, however, must first be monitored to detect if carbon dioxide is leaking back out to the atmosphere. As an alternative to traditional large ground-based sensor networks to monitor CO2 levels for leaks, unmanned aircraft offer the potential to perform in-situ atmospheric leak detection over large areas for a fraction of the cost. This project developed a proof-of-concept sensor system to map relative carbon dioxide levels to detect potential leaks. The sensor system included a Sensair K-30 FR CO2 sensor, GPS, and altimeter connected an Arduino microcontroller which logged data to an onboard SD card. Ground tests were performed to verify and calibrate the system including wind tunnel tests to determine the optimal configuration of the system for the quickest response time (4-8 seconds based upon flowrate). Tests were then conducted over a controlled release of CO 2 in addition to over controlled rangeland fires which released carbon dioxide over a large area as would be expected from a carbon sequestration source. 3D maps of carbon dioxide were developed from the system telemetry that clearly illustrated increased CO2 levels from the fires. These tests demonstrated the system's ability to detect increased carbon dioxide concentrations in the atmosphere.

  6. Designed polar cosolvent-modified supercritical CO2 removing caffeine from and retaining catechins in green tea powder using response surface methodology.

    PubMed

    Huang, Kuo-Jong; Wu, Jia-Jiuan; Chiu, Yung-Ho; Lai, Cheng-Yung; Chang, Chieh-Ming J

    2007-10-31

    This study examines cosolvent-modified supercritical carbon dioxide (SC-CO2) to remove caffeine from and to retain catechins in green tea powder. The response surface method was adopted to determine the optimal operation conditions in terms of the extraction efficiencies and concentration factors of caffeine and catechins during the extractions. When SC-CO2 was used at 333 K and 300 bar, 91.5% of the caffeine was removed and 80.8% of catechins were retained in the tea: 3600 g of carbon dioxide was used in the extraction of 4 g of tea soaked with 1 g of water. Under the same extraction conditions, 10 g of water was added to <800 g of carbon dioxide in an extraction that completely removed caffeine (that is, the caffeine extraction efficiency was 100%). The optimal result as predicted by three-factor response surface methodology and supported by experimental data was that in 1.5 h of extraction, 640 g of carbon dioxide at 323 K and 275 bar with the addition of 6 g of water extracted 71.9% of the caffeine while leaving 67.8% of the catechins in 8 g of tea. Experimental data indicated that supercritical carbon dioxide decaffeination increased the concentrations of caffeine in the SC-CO2 extracts at 353 K.

  7. Optimizing supercritical carbon dioxide in the inactivation of bacteria in clinical solid waste by using response surface methodology

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Hossain, Md. Sohrab; Nik Ab Rahman, Nik Norulaini; Balakrishnan, Venugopal

    2015-04-15

    Highlights: • Supercritical carbon dioxide sterilization of clinical solid waste. • Inactivation of bacteria in clinical solid waste using supercritical carbon dioxide. • Reduction of the hazardous exposure of clinical solid waste. • Optimization of the supercritical carbon dioxide experimental conditions. - Abstract: Clinical solid waste (CSW) poses a challenge to health care facilities because of the presence of pathogenic microorganisms, leading to concerns in the effective sterilization of the CSW for safe handling and elimination of infectious disease transmission. In the present study, supercritical carbon dioxide (SC-CO{sub 2}) was applied to inactivate gram-positive Staphylococcus aureus, Enterococcus faecalis, Bacillus subtilis,more » and gram-negative Escherichia coli in CSW. The effects of SC-CO{sub 2} sterilization parameters such as pressure, temperature, and time were investigated and optimized by response surface methodology (RSM). Results showed that the data were adequately fitted into the second-order polynomial model. The linear quadratic terms and interaction between pressure and temperature had significant effects on the inactivation of S. aureus, E. coli, E. faecalis, and B. subtilis in CSW. Optimum conditions for the complete inactivation of bacteria within the experimental range of the studied variables were 20 MPa, 60 °C, and 60 min. The SC-CO{sub 2}-treated bacterial cells, observed under a scanning electron microscope, showed morphological changes, including cell breakage and dislodged cell walls, which could have caused the inactivation. This espouses the inference that SC-CO{sub 2} exerts strong inactivating effects on the bacteria present in CSW, and has the potential to be used in CSW management for the safe handling and recycling-reuse of CSW materials.« less

  8. Integrated Assessment of Carbon Dioxide Removal

    NASA Astrophysics Data System (ADS)

    Rickels, W.; Reith, F.; Keller, D.; Oschlies, A.; Quaas, M. F.

    2018-03-01

    To maintain the chance of keeping the average global temperature increase below 2°C and to limit long-term climate change, removing carbon dioxide from the atmosphere (carbon dioxide removal, CDR) is becoming increasingly necessary. We analyze optimal and cost-effective climate policies in the dynamic integrated assessment model (IAM) of climate and the economy (DICE2016R) and investigate (1) the utilization of (ocean) CDR under different climate objectives, (2) the sensitivity of policies with respect to carbon cycle feedbacks, and (3) how well carbon cycle feedbacks are captured in the carbon cycle models used in state-of-the-art IAMs. Overall, the carbon cycle model in DICE2016R shows clear improvements compared to its predecessor, DICE2013R, capturing much better long-term dynamics and also oceanic carbon outgassing due to excess oceanic storage of carbon from CDR. However, this comes at the cost of a (too) tight short-term remaining emission budget, limiting the model suitability to analyze low-emission scenarios accurately. With DICE2016R, the compliance with the 2°C goal is no longer feasible without negative emissions via CDR. Overall, the optimal amount of CDR has to take into account (1) the emission substitution effect and (2) compensation for carbon cycle feedbacks.

  9. Development of a prototype regeneration carbon dioxide absorber. [for use in EVA conditions

    NASA Technical Reports Server (NTRS)

    Patel, P. S.; Baker, B. S.

    1977-01-01

    A prototype regenerable carbon dioxide absorber was developed to maintain the environmental quality of the portable life support system. The absorber works on the alkali metal carbonate-bicarbonate solid-gas reaction to remove carbon dioxide from the atmosphere. The prototype sorber module was designed, fabricated, and tested at simulated extravehicular activity conditions to arrive at optimum design. The unit maintains sorber outlet concentration below 5 mm Hg. An optimization study was made with respect to heat transfer, temperature control, sorbent utilization, sorber life and regenerability, and final size of the module. Important parameters influencing the capacity of the final absorber unit were identified and recommendations for improvement were made.

  10. Scenarios for optimizing potato productivity in a lunar CELSS

    NASA Technical Reports Server (NTRS)

    Wheeler, R. M.; Morrow, R. C.; Tibbitts, T. W.; Bula, R. J.

    1992-01-01

    The use of controlled ecological life support system (CELSS) in the development and growth of large-scale bases on the Moon will reduce the expense of supplying life support materials from Earth. Such systems would use plants to produce food and oxygen, remove carbon dioxide, and recycle water and minerals. In a lunar CELSS, several factors are likely to be limiting to plant productivity, including the availability of growing area, electrical power, and lamp/ballast weight for lighting systems. Several management scenarios are outlined in this discussion for the production of potatoes based on their response to irradiance, photoperiod, and carbon dioxide concentration. Management scenarios that use 12-hr photoperiods, high carbon dioxide concentrations, and movable lamp banks to alternately irradiate halves of the growing area appear to be the most efficient in terms of growing area, electrical power, and lamp weights. However, the optimal scenario will be dependent upon the relative 'costs' of each factor.

  11. Optimizing oil and xanthorrhizol extraction from Curcuma xanthorrhiza Roxb. rhizome by supercritical carbon dioxide.

    PubMed

    Salea, Rinaldi; Widjojokusumo, Edward; Veriansyah, Bambang; Tjandrawinata, Raymond R

    2014-09-01

    Oil and xanthorrhizol extraction from Curcuma xanthorrhiza Roxb. rhizome by supercritical carbon dioxide was optimized using Taguchi method. The factors considered were pressure, temperature, carbon dioxide flowrate and time at levels ranging between 10-25 MPa, 35-60 °C, 10-25 g/min and 60-240 min respectively. The highest oil yield (8.0 %) was achieved at factor combination of 15 MPa, 50 °C, 20 g/min and 180 min whereas the highest xanthorrhizol content (128.3 mg/g oil) in Curcuma xanthorrhiza oil was achieved at a factor combination of 25 MPa, 50 °C, 15 g/min and 60 min. Soxhlet extraction with n-hexane and percolation with ethanol gave oil yield of 5.88 %, 11.73 % and xanthorrhizol content of 42.6 mg/g oil, 75.5 mg/g oil, respectively. The experimental oil yield and xanthorrhizol content at optimum conditions agreed favourably with values predicted by computational process. The xanthorrizol content extracted using supercritical carbon dioxide was higher than extracted using Soxhlet extraction and percolation process.

  12. Electrochemical response of carbon paste electrode modified with mixture of titanium dioxide/zirconium dioxide in the detection of heavy metals: lead and cadmium.

    PubMed

    Nguyen, Phuong Khanh Quoc; Lunsford, Suzanne K

    2012-11-15

    A novel carbon modified electrode was developed by incorporating titanium dioxide/zirconium dioxide into the graphite carbon paste electrode to detect heavy metals-cadmium and lead. In this work, the development of the novel titanium dioxide/zirconium dioxide modified carbon paste electrode was studied to determine the optimum synthesis conditions related to the temperature, heating duration, amount and ratio of titanium dioxide/zirconium dioxide, and amount of surfactant, to create the most reproducible results. Using cyclic voltammetric (CV) analysis, this study has proven that the novel titanium dioxide/zirconium dioxide can be utilized to detect heavy metals-lead and cadmium, at relatively low concentrations (7.6×10(-6) M and 1.1×10(-5) M for Pb and Cd, respectively) at optimum pH value (pH=3). From analyzing CV data the optimal electrodes surface area was estimated to be 0.028 (±0.003) cm(2). Also, under the specific experimental conditions, electron transfer coefficients were estimated to be 0.44 and 0.33 along with the heterogeneous electron transfer rate constants of 5.64×10(-3) and 2.42×10(-3) (cm/s) for Pb and Cd, respectively. Copyright © 2012 Elsevier B.V. All rights reserved.

  13. Understanding trends in electrochemical carbon dioxide reduction rates

    DOE PAGES

    Liu, Xinyan; Xiao, Jianping; Peng, Hongjie; ...

    2017-05-22

    Electrochemical carbon dioxide reduction to fuels presents one of the great challenges in chemistry. Herein we present an understanding of trends in electrocatalytic activity for carbon dioxide reduction over different metal catalysts that rationalize a number of experimental observations including the selectivity with respect to the competing hydrogen evolution reaction. We also identify two design criteria for more active catalysts. The understanding is based on density functional theory calculations of activation energies for electrochemical carbon monoxide reduction as a basis for an electrochemical kinetic model of the process. Furthermore, we develop scaling relations relating transition state energies to the carbonmore » monoxide adsorption energy and determine the optimal value of this descriptor to be very close to that of copper.« less

  14. Understanding trends in electrochemical carbon dioxide reduction rates

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Liu, Xinyan; Xiao, Jianping; Peng, Hongjie

    Electrochemical carbon dioxide reduction to fuels presents one of the great challenges in chemistry. Herein we present an understanding of trends in electrocatalytic activity for carbon dioxide reduction over different metal catalysts that rationalize a number of experimental observations including the selectivity with respect to the competing hydrogen evolution reaction. We also identify two design criteria for more active catalysts. The understanding is based on density functional theory calculations of activation energies for electrochemical carbon monoxide reduction as a basis for an electrochemical kinetic model of the process. Furthermore, we develop scaling relations relating transition state energies to the carbonmore » monoxide adsorption energy and determine the optimal value of this descriptor to be very close to that of copper.« less

  15. The 2014 ASCENDS Field Campaign - a Carbon Dioxide Laser Absorption Spectrometer Perspective

    NASA Astrophysics Data System (ADS)

    Spiers, G. D.; Menzies, R. T.; Jacob, J. C.; Geier, S.; Fregoso, S. F.

    2014-12-01

    NASA's ASCENDS mission has been flying several candidate lidar instruments on board the NASA DC-8 aircraft to obtain column integrated measurements of Carbon Dioxide. Each instrument uses a different approach to making the measurement and combined they have allowed for the informed development of the ASCENDS mission measurement requirements(1). The JPL developed Carbon Dioxide Laser Absorption Spectrometer, CO2LAS is one of these instruments. The CO2LAS measures the weighted, column averaged carbon dioxide between the aircraft and the ground using a continuous-wave heterodyne technique. The instrument operates at a 2.05 micron wavelength optimized for enhancing sensitivity to boundary layer carbon dioxide. Since the 2013 field campaign the instrument has undergone significant upgrades that improve the data collection efficiency and instrument stability and has recently been re-integrated onto the NASA DC-8 for the August 2014 ASCENDS field campaign. This presentation will summarize the instrument and algorithm improvements and review the 2014 field campaign flights and preliminary results. (1) Abshire, J.B. et al., "An overview of NASA's ASCENDS Mission lidar measurement requirements", submitted to 2014 Fall AGU Conference.

  16. Optimal Estimation Retrieval of Mid-Tropospheric Carbon Dioxide and Methane Using the Atmospheric Infrared Sounder (AIRS) Radiances.

    NASA Astrophysics Data System (ADS)

    Imbiriba, B.

    2017-12-01

    Carbon dioxide and methane are the most important anthropogenic greenhouse contributions to climate change. Space-based remote sensing measurements of carbon dioxide and methane would help to understand the generation, absorption and transport mechanisms and characterization of such gases. Space-based hyperspectral thermal infrared remote sensing measurements using NASA's Atmospheric Infrared Sounder (AIRS) instrument can provide 14 years of observations of radiances at the top of the atmosphere.Here we present a Optimal Estimation based retrieval system for surface temperature, water vapor, carbon dioxide, methane, and other trace gases, based on selected AIRS channels that allow for CO2 sensitivity down to the lower part of the middle troposphere. We use the SARTA fast forward model developed at University of Maryland Baltimore County, and use the ERA product for prior state atmospheric profiles.We retrieve CO2 and CH4 column concentrations across 14 years of AIRS measurements, for clear only field-of-views, using the AIRS L1B Calibration Subset. We then compare these to the standard AIRS L2 CO2 retrievals, as well TES, and OCO2 data, and the GlobalView/CarbonTracker CO2/CH4 model data from NOAA. We evaluate the hemispheric seasonal cycles, growth rates, and possible interhemispheric transport. We also evaluate the use of atmospheric nitrous oxide concentration to correct for the errors in the temperature profile.

  17. Enzyme microheterogeneous hydration and stabilization in supercritical carbon dioxide.

    PubMed

    Silveira, Rodrigo L; Martínez, Julian; Skaf, Munir S; Martínez, Leandro

    2012-05-17

    Supercritical carbon dioxide is a promising green-chemistry solvent for many enzyme-catalyzed chemical reactions, yet the striking stability of some enzymes in such unconventional environments is not well understood. Here, we investigate the stabilization of the Candida antarctica Lipase B (CALB) in supercritical carbon dioxide-water biphasic systems using molecular dynamics simulations. The preservation of the enzyme structure and optimal activity depend on the presence of small amounts of water in the supercritical dispersing medium. When the protein is at least partially hydrated, water molecules bind to specific sites on the enzyme surface and prevent carbon dioxide from penetrating its catalytic core. Strikingly, water and supercritical carbon dioxide cover the protein surface quite heterogeneously. In the first solvation layer, the hydrophilic residues at the surface of the protein are able to pin down patches of water, whereas carbon dioxide solvates preferentially hydrophobic surface residues. In the outer solvation shells, water molecules tend to cluster predominantly on top of the larger water patches of the first solvation layer instead of spreading evenly around the remainder of the protein surface. For CALB, this exposes the substrate-binding region of the enzyme to carbon dioxide, possibly facilitating diffusion of nonpolar substrates into the catalytic funnel. Therefore, by means of microheterogeneous solvation, enhanced accessibility of hydrophobic substrates to the active site can be achieved, while preserving the functional structure of the enzyme. Our results provide a molecular picture on the nature of the stability of proteins in nonaqueous media.

  18. Optimized Unlike-Pair Interactions for Water-Carbon Dioxide Mixtures described by the SPC/E and EPM2 Models

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Vlcek, Lukas; Chialvo, Ariel A; Cole, David

    The unlike- pair interaction parameters for the SPC/E- EPM2 models have been optimized to reproduce the mutual solubility of water and carbon dioxide at the conditions of liquid- supercritical fluid phase equilibria. An efficient global optimization of the parameters is achieved through an implementation of the coupling parameter approach, adapted to phase equilibria calculations in the Gibbs ensemble, that explicitly corrects for the over- polarization of the SPC/E water molecule in the non- polar CO2 environments. The resulting H2O- CO2 force field reproduces accurately the available experimental solubilities at the two fluid phases in equilibria as well as the correspondingmore » species tracer diffusion coefficients.« less

  19. Exploring How Technology Growth Limits Impact Optimal Carbon dioxide Mitigation Pathways

    EPA Science Inventory

    Energy system optimization models prescribe the optimal mix of technologies and fuels for meeting energy demands over a time horizon, subject to energy supplies, demands, and other constraints. When optimizing, these models will, to the extent allowed, favor the least cost combin...

  20. Mars methane engine

    NASA Technical Reports Server (NTRS)

    Bui, Hung; Coletta, Chris; Debois, Alain

    1994-01-01

    The feasibility of an internal combustion engine operating on a mixture of methane, carbon dioxide, and oxygen has been verified by previous design groups for the Mars Methane Engine Project. Preliminary stoichiometric calculations examined the theoretical fuel-air ratios needed for the combustion of methane. Installation of a computer data acquisition system along with various ancillary components will enable the performance of the engine, running on the described methane mixture, to be optimized with respect to minimizing excess fuel. Theoretical calculations for stoichiometric combustion of methane-oxygen-carbon dioxide mixtures yielded a ratio of 1:2:4.79 for a methane-oxygen-carbon dioxide mixture. Empirical data shows the values to be closer to 1:2.33:3.69 for optimum operation.

  1. Supercritical CO2 extraction of candlenut oil: process optimization using Taguchi orthogonal array and physicochemical properties of the oil.

    PubMed

    Subroto, Erna; Widjojokusumo, Edward; Veriansyah, Bambang; Tjandrawinata, Raymond R

    2017-04-01

    A series of experiments was conducted to determine optimum conditions for supercritical carbon dioxide extraction of candlenut oil. A Taguchi experimental design with L 9 orthogonal array (four factors in three levels) was employed to evaluate the effects of pressure of 25-35 MPa, temperature of 40-60 °C, CO 2 flow rate of 10-20 g/min and particle size of 0.3-0.8 mm on oil solubility. The obtained results showed that increase in particle size, pressure and temperature improved the oil solubility. The supercritical carbon dioxide extraction at optimized parameters resulted in oil yield extraction of 61.4% at solubility of 9.6 g oil/kg CO 2 . The obtained candlenut oil from supercritical carbon dioxide extraction has better oil quality than oil which was extracted by Soxhlet extraction using n-hexane. The oil contains high unsaturated oil (linoleic acid and linolenic acid), which have many beneficial effects on human health.

  2. Carbon Dioxide Separation Using Thermally Optimized Membranes

    NASA Astrophysics Data System (ADS)

    Young, J. S.; Jorgensen, B. S.; Espinoza, B. F.; Weimer, M. W.; Jarvinen, G. D.; Greenberg, A.; Khare, V.; Orme, C. J.; Wertsching, A. K.; Peterson, E. S.; Hopkins, S. D.; Acquaviva, J.

    2002-05-01

    The purpose of this project is to develop polymeric-metallic membranes for carbon dioxide separations that operate under a broad range of industrially relevant conditions not accessible with present membrane units. The last decade has witnessed a dramatic increase in the use of polymer membranes as an effective, economic and flexible tool for many commercial gas separations including air separation, the recovery of hydrogen from nitrogen, carbon monoxide, and methane mixtures, and the removal of carbon dioxide from natural gas. In each of these applications, high fluxes and excellent selectivities have relied on glassy polymer membranes which separate gases based on both size and solubility differences. To date, however, this technology has focused on optimizing materials for near ambient conditions. The development of polymeric materials that achieve the important combination of high selectivity, high permeability, and mechanical stability at temperatures significantly above 25oC and pressures above 10 bar, respectively, has been largely ignored. Consequently, there is a compelling rationale for the exploration of a new realm of polymer membrane separations. Indeed, the development of high temperature polymeric-metallic composite membranes for carbon dioxide separation at temperatures of 100-450 oC and pressures of 10-150 bar would provide a pivotal contribution with both economic and environmental benefits. Progress to date includes the first ever fabrication of a polymeric-metallic membrane that is selective from room temperature to 370oC. This achievement represents the highest demonstrated operating temperature at which a polymeric based membrane has successfully functioned. Additionally, we have generated the first polybenzamidizole silicate molecular composites. Finally, we have developed a technique that has enabled the first-ever simultaneous measurements of gas permeation and membrane compaction at elevated temperatures. This technique provides a unique approach to the optimization of long-term membrane performance under challenging operating conditions.

  3. Optimal Detection of Global Warming using Temperature Profiles

    NASA Technical Reports Server (NTRS)

    Leroy, Stephen S.

    1997-01-01

    Optimal fingerprinting is applied to estimate the amount of time it would take to detect warming by increased concentrations of carbon dioxide in monthly averages of temperature profiles over the Indian Ocean.

  4. Full System Modeling and Validation of the Carbon Dioxide Removal Assembly

    NASA Technical Reports Server (NTRS)

    Coker, Robert; Knox, James; Gauto, Hernando; Gomez, Carlos

    2014-01-01

    The Atmosphere Revitalization Recovery and Environmental Monitoring (ARREM) project was initiated in September of 2011 as part of the Advanced Exploration Systems (AES) program. Under the ARREM project, testing of sub-scale and full-scale systems has been combined with multiphysics computer simulations for evaluation and optimization of subsystem approaches. In particular, this paper describes the testing and modeling of various subsystems of the carbon dioxide removal assembly (CDRA). The goal is a full system predictive model of CDRA to guide system optimization and development. The development of the CO2 removal and associated air-drying subsystem hardware under the ARREM project is discussed in a companion paper.

  5. Computer Simulation and Modeling of CO2 Removal Systems for Exploration 2013-2014

    NASA Technical Reports Server (NTRS)

    Coker, R.; Knox, J.; Gomez, C.

    2015-01-01

    The Atmosphere Revitalization Recovery and Environmental Monitoring (ARREM) project was initiated in September of 2011 as part of the Advanced Exploration Systems (AES) program. Under the ARREM project and the follow-on Life Support Systems (LSS) project, testing of sub-scale and full-scale systems has been combined with multiphysics computer simulations for evaluation and optimization of subsystem approaches. In particular, this paper will describes the testing and 1-D modeling of the combined water desiccant and carbon dioxide sorbent subsystems of the carbon dioxide removal assembly (CDRA). The goal is a full system predictive model of CDRA to guide system optimization and development.

  6. Optimal diving behaviour and respiratory gas exchange in birds.

    PubMed

    Halsey, Lewis G; Butler, Patrick J

    2006-11-01

    This review discusses the advancements in our understanding of the physiology and behaviour of avian diving that have been underpinned by optimal foraging theory and the testing of optimal models. To maximise their foraging efficiency during foraging periods, diving birds must balance numerous factors that are directly or indirectly related to the replenishment of the oxygen stores and the removal of excess carbon dioxide. These include (1) the time spent underwater (which diminishes the oxygen supply, increases carbon dioxide levels and may even include a build up of lactate due to anaerobic metabolism), (2) the time spent at the surface recovering from the previous dive and preparing for the next (including reloading their oxygen supply, decreasing their carbon dioxide levels and possibly also metabolising lactate) and (3) the trade-off between maximising oxygen reserves for consumption underwater by taking in more air to the respiratory system, and minimising the energy costs of positive buoyancy caused by this air, to maximise the time available underwater to forage. Due to its importance in avian diving, replenishment of the oxygen stores has become integral to models of optimal diving, which predict the time budgeting of animals foraging underwater. While many of these models have been examined qualitatively, such tests of predictive trends appear fallible and only quantifiable support affords strong evidence of their predictive value. This review describes how the quantification of certain optimal diving models, using tufted ducks, indeed demonstrates some predictive success. This suggests that replenishment of the oxygen stores and removal of excess carbon dioxide have significant influences on the duration of the surface period between dives. Nevertheless, present models are too simplistic to be robust predictors of diving behaviour for individual animals and it is proposed that they require refinement through the incorporation of other variables that also influence diving behaviour such as, perhaps, prey density and predator avoidance.

  7. Thermal optimality of net ecosystem exchange of carbon dioxide and underlying mechanisms

    USDA-ARS?s Scientific Manuscript database

    It has been well established that individual organisms can acclimate and adapt to temperature change to optimize their performance (i.e., achieve thermal optimality). However, whether ecosystems with an assembly of organisms would also undergo thermal optimization has not been examined on a broader ...

  8. Genetically Engineered Cyanobacteria

    NASA Technical Reports Server (NTRS)

    Zhou, Ruanbao (Inventor); Gibbons, William (Inventor)

    2015-01-01

    The disclosed embodiments provide cyanobacteria spp. that have been genetically engineered to have increased production of carbon-based products of interest. These genetically engineered hosts efficiently convert carbon dioxide and light into carbon-based products of interest such as long chained hydrocarbons. Several constructs containing polynucleotides encoding enzymes active in the metabolic pathways of cyanobacteria are disclosed. In many instances, the cyanobacteria strains have been further genetically modified to optimize production of the carbon-based products of interest. The optimization includes both up-regulation and down-regulation of particular genes.

  9. Analyses of the Integration of Carbon Dioxide Removal Assembly, Compressor, Accumulator and Sabatier Carbon Dioxide Reduction Assembly

    NASA Technical Reports Server (NTRS)

    Jeng, Frank F.; Lafuse, Sharon; Smith, Frederick D.; Lu, Sao-Dung; Knox, James C.; Campbell, Mellssa L.; Scull, Timothy D.; Green Steve

    2010-01-01

    A tool has been developed by the Sabatier Team for analyzing/optimizing CO2 removal assembly, CO2 compressor size, its operation logic, water generation from Sabatier, utilization of CO2 from crew metabolic output, and Hz from oxygen generation assembly. Tests had been conducted using CDRA/Simulation compressor set-up at MSFC in 2003. Analysis of test data has validated CO2 desorption rate profile, CO2 compressor performance, CO2 recovery and CO2 vacuum vent in CDRA desorption. Optimizing the compressor size and compressor operation logic for an integrated closed air revitalization system Is being conducted by the Sabatier Team.

  10. Thermal analysis, optimization and design of a Martian oxygen production plant

    NASA Technical Reports Server (NTRS)

    Iyer, Venkatesh A.; Sridhar, K. R.

    1991-01-01

    The objective is to optimally design the thermal components of a system that uses carbon dioxide (CO2) from the Martian atmosphere to produce oxygen (O2) for spacecraft propulsion and/or life-support. Carbon dioxide is thermally decomposed into carbon monoxide (CO) and O2 followed by the electrochemical separation of O2. The design of the overall system and its various individual components depends on, among other things, the fraction of the stoichiometric yield of O2 that can be realized in the system and the temperature of operation of the electrochemical separation membrane. The analysis indicates that a substantial reduction could be obtained in the mass and power requirements of the system if the unreacted CO2 were to be recycled. The concepts of an optimum temperature of the zirconia cell and impracticality of plant operation at low cell efficiencies are also discussed. The design of the thermal equipment is such that the mass and power requirements of the individual components and of the overall system are optimized.

  11. Calcifying Cyanobacteria - The potential of biomineralization for Carbon Capture and Storage

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Jansson, Christer G; Northen, Trent

    2010-03-26

    Employment of cyanobacteria in biomineralization of carbon dioxide by calcium carbonate precipitation offers novel and self-sustaining strategies for point-source carbon capture and sequestration. Although details of this process remain to be elucidated, a carbon-concentrating mechanism, and chemical reactions in exopolysaccharide or proteinaceous surface layers are assumed to be of crucial importance. Cyanobacteria can utilize solar energy through photosynthesis to convert carbon dioxide to recalcitrant calcium carbonate. Calcium can be derived from sources such as gypsum or industrial brine. A better understanding of the biochemical and genetic mechanisms that carry out and regulate cynaobacterial biomineralization should put us in a positionmore » where we can further optimize these steps by exploiting the powerful techniques of genetic engineering, directed evolution, and biomimetics.« less

  12. A study of power cycles using supercritical carbon dioxide as the working fluid

    NASA Astrophysics Data System (ADS)

    Schroder, Andrew Urban

    A real fluid heat engine power cycle analysis code has been developed for analyzing the zero dimensional performance of a general recuperated, recompression, precompression supercritical carbon dioxide power cycle with reheat and a unique shaft configuration. With the proposed shaft configuration, several smaller compressor-turbine pairs could be placed inside of a pressure vessel in order to avoid high speed, high pressure rotating seals. The small compressor-turbine pairs would share some resemblance with a turbocharger assembly. Variation in fluid properties within the heat exchangers is taken into account by discretizing zero dimensional heat exchangers. The cycle analysis code allows for multiple reheat stages, as well as an option for the main compressor to be powered by a dedicated turbine or an electrical motor. Variation in performance with respect to design heat exchanger pressure drops and minimum temperature differences, precompressor pressure ratio, main compressor pressure ratio, recompression mass fraction, main compressor inlet pressure, and low temperature recuperator mass fraction have been explored throughout a range of each design parameter. Turbomachinery isentropic efficiencies are implemented and the sensitivity of the cycle performance and the optimal design parameters is explored. Sensitivity of the cycle performance and optimal design parameters is studied with respect to the minimum heat rejection temperature and the maximum heat addition temperature. A hybrid stochastic and gradient based optimization technique has been used to optimize critical design parameters for maximum engine thermal efficiency. A parallel design exploration mode was also developed in order to rapidly conduct the parameter sweeps in this design space exploration. A cycle thermal efficiency of 49.6% is predicted with a 320K [47°C] minimum temperature and 923K [650°C] maximum temperature. The real fluid heat engine power cycle analysis code was expanded to study a theoretical recuperated Lenoir cycle using supercritical carbon dioxide as the working fluid. The real fluid cycle analysis code was also enhanced to study a combined cycle engine cascade. Two engine cascade configurations were studied. The first consisted of a traditional open loop gas turbine, coupled with a series of recuperated, recompression, precompression supercritical carbon dioxide power cycles, with a predicted combined cycle thermal efficiency of 65.0% using a peak temperature of 1,890K [1,617°C]. The second configuration consisted of a hybrid natural gas powered solid oxide fuel cell and gas turbine, coupled with a series of recuperated, recompression, precompression supercritical carbon dioxide power cycles, with a predicted combined cycle thermal efficiency of 73.1%. Both configurations had a minimum temperature of 306K [33°C]. The hybrid stochastic and gradient based optimization technique was used to optimize all engine design parameters for each engine in the cascade such that the entire engine cascade achieved the maximum thermal efficiency. The parallel design exploration mode was also utilized in order to understand the impact of different design parameters on the overall engine cascade thermal efficiency. Two dimensional conjugate heat transfer (CHT) numerical simulations of a straight, equal height channel heat exchanger using supercritical carbon dioxide were conducted at various Reynolds numbers and channel lengths.

  13. Optimization of an Atmospheric Carbon Source for Extremophile Cyanobacteria

    NASA Astrophysics Data System (ADS)

    Beaubien, Courtney

    This thesis examines the use of the moisture swing resin materials employed at the Center for Negative Carbon Emissions (CNCE) in order to provide carbon dioxide from ambient air to photobioreactors containing extremophile cyanobacteria cultured at the Arizona Center for Algae Technology and Innovation (AzCATI). For this purpose, a carbon dioxide feeding device was designed, built, and tested. The results indicate how much resin should be used with a given volume of algae medium: approximately 500 grams of resin can feed 1% CO2 at about three liters per minute to a ten liter medium of the Galdieria sulphuraria 5587.1 strain for one hour (equivalent to about 0.1 grams of carbon dioxide per hour per seven grams of algae). Using the resin device, the algae grew within their normal growth range: 0.096 grams of ash-free dry weight per liter over a six hour period. Future applications in which the resin-to-algae process can be utilized are discussed.

  14. Optimization of sample preparation variables for wedelolactone from Eclipta alba using Box-Behnken experimental design followed by HPLC identification.

    PubMed

    Patil, A A; Sachin, B S; Shinde, D B; Wakte, P S

    2013-07-01

    Coumestan wedelolactone is an important phytocomponent from Eclipta alba (L.) Hassk. It possesses diverse pharmacological activities, which have prompted the development of various extraction techniques and strategies for its better utilization. The aim of the present study is to develop and optimize supercritical carbon dioxide assisted sample preparation and HPLC identification of wedelolactone from E. alba (L.) Hassk. The response surface methodology was employed to study the optimization of sample preparation using supercritical carbon dioxide for wedelolactone from E. alba (L.) Hassk. The optimized sample preparation involves the investigation of quantitative effects of sample preparation parameters viz. operating pressure, temperature, modifier concentration and time on yield of wedelolactone using Box-Behnken design. The wedelolactone content was determined using validated HPLC methodology. The experimental data were fitted to second-order polynomial equation using multiple regression analysis and analyzed using the appropriate statistical method. By solving the regression equation and analyzing 3D plots, the optimum extraction conditions were found to be: extraction pressure, 25 MPa; temperature, 56 °C; modifier concentration, 9.44% and extraction time, 60 min. Optimum extraction conditions demonstrated wedelolactone yield of 15.37 ± 0.63 mg/100 g E. alba (L.) Hassk, which was in good agreement with the predicted values. Temperature and modifier concentration showed significant effect on the wedelolactone yield. The supercritical carbon dioxide extraction showed higher selectivity than the conventional Soxhlet assisted extraction method. Copyright © 2013 Elsevier Masson SAS. All rights reserved.

  15. Supercritical Carbon Dioxide Extraction of the Oak Silkworm (Antheraea pernyi) Pupal Oil: Process Optimization and Composition Determination

    PubMed Central

    Pan, Wen-Juan; Liao, Ai-Mei; Zhang, Jian-Guo; Dong, Zeng; Wei, Zhao-Jun

    2012-01-01

    Supercritical carbon dioxide (SC-CO2) extraction of oil from oak silkworm pupae was performed in the present research. Response surface methodology (RSM) was applied to optimize the parameters of SC-CO2 extraction, including extraction pressure, temperature, time and CO2 flow rate on the yield of oak silkworm pupal oil (OSPO). The optimal extraction condition for oil yield within the experimental range of the variables researched was at 28.03 MPa, 1.83 h, 35.31 °C and 20.26 L/h as flow rate of CO2. Under this condition, the oil yield was predicted to be 26.18%. The oak silkworm pupal oil contains eight fatty acids, and is rich in unsaturated fatty acids and α-linolenic acid (ALA), accounting for 77.29% and 34.27% in the total oil respectively. PMID:22408458

  16. Effects of stand and inter-specific stocking on maximizing standing tree carbon stocks in the eastern United States

    Treesearch

    Christopher W. Woodall; Anthony W. D' Amato; John B. Bradford; Andrew O. Finley

    2011-01-01

    There is expanding interest in management strategies that maximize forest carbon (C) storage to mitigate increased atmospheric carbon dioxide. The tremendous tree species diversity and range of stand stocking found across the eastern United States presents a challenge for determining optimal combinations for the maximization of standing tree C storage. Using a...

  17. Adaptation of SUBSTOR for controlled-environment potato production with elevated carbon dioxide

    NASA Technical Reports Server (NTRS)

    Fleisher, D. H.; Cavazzoni, J.; Giacomelli, G. A.; Ting, K. C.; Janes, H. W. (Principal Investigator)

    2003-01-01

    The SUBSTOR crop growth model was adapted for controlled-environment hydroponic production of potato (Solanum tuberosum L. cv. Norland) under elevated atmospheric carbon dioxide concentration. Adaptations included adjustment of input files to account for cultural differences between the field and controlled environments, calibration of genetic coefficients, and adjustment of crop parameters including radiation use efficiency. Source code modifications were also performed to account for the absorption of light reflected from the surface below the crop canopy, an increased leaf senescence rate, a carbon (mass) balance to the model, and to modify the response of crop growth rate to elevated atmospheric carbon dioxide concentration. Adaptations were primarily based on growth and phenological data obtained from growth chamber experiments at Rutgers University (New Brunswick, N.J.) and from the modeling literature. Modified-SUBSTOR predictions were compared with data from Kennedy Space Center's Biomass Production Chamber for verification. Results show that, with further development, modified-SUBSTOR will be a useful tool for analysis and optimization of potato growth in controlled environments.

  18. Molecular simulation of gas adsorption and diffusion in a breathing MOF using a rigid force field.

    PubMed

    García-Pérez, E; Serra-Crespo, P; Hamad, S; Kapteijn, F; Gascon, J

    2014-08-14

    Simulation of gas adsorption in flexible porous materials is still limited by the slow progress in the development of flexible force fields. Moreover, the high computational cost of such flexible force fields may be a drawback even when they are fully developed. In this work, molecular simulations of gas adsorption and diffusion of carbon dioxide and methane in NH2-MIL-53(Al) are carried out using a linear combination of two crystallographic structures with rigid force fields. Once the interactions of carbon dioxide molecules and the bridging hydroxyls groups of the framework are optimized, an excellent match is found for simulations and experimental data for the adsorption of methane and carbon dioxide, including the stepwise uptake due to the breathing effect. In addition, diffusivities of pure components are calculated. The pore expansion by the breathing effect influences the self-diffusion mechanism and much higher diffusivities are observed at relatively high adsorbate loadings. This work demonstrates that using a rigid force field combined with a minimum number of experiments, reproduces adsorption and simulates diffusion of carbon dioxide and methane in the flexible metal-organic framework NH2-MIL-53(Al).

  19. Optimization of carbon mitigation paths in the power sector of Shenzhen, China

    NASA Astrophysics Data System (ADS)

    Li, Xin; Hu, Guangxiao; Duan, Ying; Ji, Junping

    2017-08-01

    This paper studied the carbon mitigation paths of the power sector in Shenzhen, China from a supply-side perspective. We investigated the carbon mitigation potentials and investments of seventeen mitigation technologies in the power sector, and employed a linear programming method to optimize the mitigation paths. The results show that: 1) The total carbon mitigation potential is 5.95 MtCO2 in 2020 in which the adjustment of power supply structure, technical improvements of existing coal- and gas-fired power plant account for 87.5%,6.5% and 6.0%, respectively. 2) In the optimal path, the avoided carbon dioxide to meet the local government’s mitigation goal in power sector is 1.26 MtCO2.The adjustment of power supply structure and technical improvement of the coal-fired power plants are the driving factors of carbon mitigation, with contributions to total carbon mitigation are 72.6% and 27.4%, respectively.

  20. Multiscale Metabolic Modeling of C4 Plants: Connecting Nonlinear Genome-Scale Models to Leaf-Scale Metabolism in Developing Maize Leaves

    PubMed Central

    Bogart, Eli; Myers, Christopher R.

    2016-01-01

    C4 plants, such as maize, concentrate carbon dioxide in a specialized compartment surrounding the veins of their leaves to improve the efficiency of carbon dioxide assimilation. Nonlinear relationships between carbon dioxide and oxygen levels and reaction rates are key to their physiology but cannot be handled with standard techniques of constraint-based metabolic modeling. We demonstrate that incorporating these relationships as constraints on reaction rates and solving the resulting nonlinear optimization problem yields realistic predictions of the response of C4 systems to environmental and biochemical perturbations. Using a new genome-scale reconstruction of maize metabolism, we build an 18000-reaction, nonlinearly constrained model describing mesophyll and bundle sheath cells in 15 segments of the developing maize leaf, interacting via metabolite exchange, and use RNA-seq and enzyme activity measurements to predict spatial variation in metabolic state by a novel method that optimizes correlation between fluxes and expression data. Though such correlations are known to be weak in general, we suggest that developmental gradients may be particularly suited to the inference of metabolic fluxes from expression data, and we demonstrate that our method predicts fluxes that achieve high correlation with the data, successfully capture the experimentally observed base-to-tip transition between carbon-importing tissue and carbon-exporting tissue, and include a nonzero growth rate, in contrast to prior results from similar methods in other systems. PMID:26990967

  1. Final Report - "CO2 Sequestration in Cell Biomass of Chlorobium Thiosulfatophilum"

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    James L. Gaddy, PhD; Ching-Whan Ko, PhD

    2009-05-04

    World carbon dioxide emissions from the combustion of fossil fuels have increased at a rate of about 3 percent per year during the last 40 years to over 24 billion tons today. While a number of methods have been proposed and are under study for dealing with the carbon dioxide problem, all have advantages as well as disadvantages which limit their application. The anaerobic bacterium Chlorobium thiosulfatophilum uses hydrogen sulfide and carbon dioxide to produce elemental sulfur and cell biomass. The overall objective of this project is to develop a commercial process for the biological sequestration of carbon dioxide andmore » simultaneous conversion of hydrogen sulfide to elemental sulfur. The Phase I study successfully demonstrated the technical feasibility of utilizing this bacterium for carbon dioxide sequestration and hydrogen sulfide conversion to elemental sulfur by utilizing the bacterium in continuous reactor studies. Phase II studies involved an advanced research and development to develop the engineering and scale-up parameters for commercialization of the technology. Tasks include culture isolation and optimization studies, further continuous reactor studies, light delivery systems, high pressure studies, process scale-up, a market analysis and economic projections. A number of anaerobic and aerobic microorgansims, both non-photosynthetic and photosynthetic, were examined to find those with the fastest rates for detailed study to continuous culture experiments. C. thiosulfatophilum was selected for study to anaerobically produce sulfur and Thiomicrospira crunogena waws selected for study to produce sulfate non-photosynthetically. Optimal conditions for growth, H2S and CO2 comparison, supplying light and separating sulfur were defined. The design and economic projections show that light supply for photosynthetic reactions is far too expensive, even when solar systems are considered. However, the aerobic non-photosynthetic reaction to produce sulfate with T. crunogena produces a reasonable return when treating a sour gas stream of 120 million SCFD containing 2.5 percent H2S. In this case, the primary source of revenue is from desulfurization of the gas stream. While the technology has significant application in sequestering carbon dioxide in cell biomass or single cell proten (SCP), perhaps the most immediate application is in desulfurizing LGNG or other gas streams. This biological approach is a viable economical alternative to existing hydrogen sulfide removal technology, and is not sensitive to the presence of hydrocarbons which act as catalyst poisons.« less

  2. Conversion of carbon dioxide to carbon monoxide by pulse dielectric barrier discharge plasma

    NASA Astrophysics Data System (ADS)

    Wang, Taobo; Liu, Hongxia; Xiong, Xiang; Feng, Xinxin

    2017-01-01

    The conversion of carbon dioxide (CO2) to carbon monoxide (CO) was investigated in a non-thermal plasma dielectric barrier discharge (DBD) reactor, and the effects of different process conditions on the CO2 conversion were investigated. The results showed that the increase of input power could optimize the conversion of CO2 to CO. The CO2 conversion and CO yield were negatively correlated with the gas flow rate, but there was an optimum gas flow rate, that made the CO selectivity best. The carrier gas (N2, Ar) was conducive to the conversion of CO2, and the effect of N2 as carrier gas was better than Ar. The conversion of CO2 to CO was enhanced by addition of the catalyst (5A molecular sieve).

  3. Optimal weighting of data to detect climatic change - Application to the carbon dioxide problem

    NASA Technical Reports Server (NTRS)

    Bell, T. L.

    1982-01-01

    It is suggested that a weighting of surface temperature data, using information about the expected level of warming in different seasons and geographical regions and statistical information about the amount of natural variability in surface temperature, can improve the chances of early detection of carbon dioxide concentration-induced climatic warming. A preliminary analysis of the optimal weighting method presented suggests that it is 25 per cent more effective in revealing surface warming than the conventional method, in virtue of the fact that 25 per cent more data must conventionally be analyzed in order to arrive at a similar probability of detection. An approximate calculation suggests that the warming ought to have already been detected, if the only sources of significant surface temperature variability had time scales of less than one year.

  4. Laser welding of fused quartz

    DOEpatents

    Piltch, Martin S.; Carpenter, Robert W.; Archer, III, McIlwaine

    2003-06-10

    Refractory materials, such as fused quartz plates and rods are welded using a heat source, such as a high power continuous wave carbon dioxide laser. The radiation is optimized through a process of varying the power, the focus, and the feed rates of the laser such that full penetration welds may be accomplished. The process of optimization varies the characteristic wavelengths of the laser until the radiation is almost completely absorbed by the refractory material, thereby leading to a very rapid heating of the material to the melting point. This optimization naturally occurs when a carbon dioxide laser is used to weld quartz. As such this method of quartz welding creates a minimum sized heat-affected zone. Furthermore, the welding apparatus and process requires a ventilation system to carry away the silicon oxides that are produced during the welding process to avoid the deposition of the silicon oxides on the surface of the quartz plates or the contamination of the welds with the silicon oxides.

  5. Optimization of Location-Routing Problem for Cold Chain Logistics Considering Carbon Footprint.

    PubMed

    Wang, Songyi; Tao, Fengming; Shi, Yuhe

    2018-01-06

    In order to solve the optimization problem of logistics distribution system for fresh food, this paper provides a low-carbon and environmental protection point of view, based on the characteristics of perishable products, and combines with the overall optimization idea of cold chain logistics distribution network, where the green and low-carbon location-routing problem (LRP) model in cold chain logistics is developed with the minimum total costs as the objective function, which includes carbon emission costs. A hybrid genetic algorithm with heuristic rules is designed to solve the model, and an example is used to verify the effectiveness of the algorithm. Furthermore, the simulation results obtained by a practical numerical example show the applicability of the model while provide green and environmentally friendly location-distribution schemes for the cold chain logistics enterprise. Finally, carbon tax policies are introduced to analyze the impact of carbon tax on the total costs and carbon emissions, which proves that carbon tax policy can effectively reduce carbon dioxide emissions in cold chain logistics network.

  6. Carbon emission and sequestration of urban turfgrass systems in Hong Kong.

    PubMed

    Kong, Ling; Shi, Zhengjun; Chu, L M

    2014-03-01

    Climate change is more than just a global issue. Locally released carbon dioxide may lead to a rise in global ambient temperature and influence the surrounding climate. Urban greenery may mitigate this as they can remove carbon dioxide by storing carbon in substrates and vegetation. On the other hand, urban greenery systems which are under intense management and maintenance may contribute to the emission of carbon dioxide or other greenhouse gases. The impact of urban greenery on carbon balance in major metropolitan areas thus remains controversial. We investigated the carbon footprints of urban turf operation and maintenance by conducting a research questionnaire on different Hong Kong turfs in 2012, and showed that turf maintenance contributed 0.17 to 0.63 kg Ce m(-2)y(-1) to carbon emissions. We also determined the carbon storage of turfs at 0.05 to 0.21 kg C m(-2) for aboveground grass biomass and 1.26 to 4.89 kg C m(-2) for soils (to 15 cm depth). We estimated that the carbon sink capacity of turfs could be offset by carbon emissions in 5-24 years under current management patterns, shifting from carbon sink to carbon source. Our study suggested that maintenance management played a key role in the carbon budget and footprint of urban greeneries. The environmental impact of turfgrass systems can be optimized by shifting away from empirically designed maintenance schedules towards rational ones based on carbon sink and emission principles. Copyright © 2014 Elsevier B.V. All rights reserved.

  7. Can We Estimate Injected Carbon Dioxide Prior to the Repeat Survey in 4D Seismic Monitoring Scheme?

    NASA Astrophysics Data System (ADS)

    Sakai, A.

    2005-12-01

    To mitigate global climate change, the geologic sequestration by injecting carbon dioxide in the aquifer and others is one of the most promising scenarios. Monitoring is required to verify the long-term safe storage of carbon dioxide in the subsurface. As evidenced in the oil industry, monitoring by time-lapse 3D seismic survey is the most effective to spatially detect fluid movements and change of pore pressure. We have conducted 3D seismic survey onshore Japan surrounding RITE/METI Iwanohara carbon dioxide injection test site. Target aquifer zone is at 1100m deep in the Pleistocene layer with 60m thick and most permeable zone is approx. 12m thick. Baseline 3D seismic survey was conducted in July-August 2003 and a monitor 3D seismic survey was in July-August 2005 by vibrating source with 10-120Hz sweep frequency band. Prior to the monitor survey, we evaluated seismic data with integrating wireline logging data. As target carbon dioxide injection layer is thin, high-resolution seismic data is required to estimate potential spreading of injected carbon dioxide. To increase seismic resolution, spectrally enhancing method was in use. The procedure is smoothing number of seismic spectral amplitude, computing well log spectrum, and constructing matching filter between seismic and well spectrum. Then it was applied to the whole seismic traces after evaluating test traces. Synthetic seismograms from logging data were computed with extracting optimal wavelets. Fitting between spectrally enhanced seismic traces and synthetic seismograms was excellent even for deviated monitor wells. Acoustic impedance was estimated by inversion of these 3D seismic traces. In analyzing logging data of sonic, density, CMR, and others, the elastic wave velocity was reconstructed by rock physics approach after estimating compositions. Based on models, velocity changes by carbon dioxide injection was evaluated. The correlation of acoustic impedance with porosity and logarithmic permeability was good and relying on this relation and geological constraints with inversion techniques, porosity and permeability was estimated in 3D volume. If the carbon dioxide movement was solely controlled by permeability, estimated permeability volume might predict the time-lapse seismic data prior to a repeat survey. We compare the estimate with the actual 4D changes and discuss related variations.

  8. Adsorption of Ammonia on Regenerable Carbon Sorbents

    NASA Technical Reports Server (NTRS)

    Wójtowicz, Marek A.; Cosgrove, Jesph E.; Serio, Michael A..; Wilburn, Monique

    2015-01-01

    Results are presented on the development of reversible sorbents for the combined carbon dioxide, moisture, and trace-contaminant (TC) removal for use in Extravehicular Activities (EVAs), and more specifically in the Primary Life Support System (PLSS). The currently available life support systems use separate units for carbon dioxide, trace contaminants, and moisture control, and the long-term objective is to replace the above three modules with a single one. Data on sorption and desorption of ammonia, which is a major TC of concern, are presented in this paper. The current TC-control technology involves the use of a packed bed of acid-impregnated granular charcoal, which is non-regenerable, and the carbon-based sorbent under development in this project can be regenerated by exposure to vacuum at room temperature. In this study, several carbon sorbents were fabricated and tested for ammonia sorption. Ammonia-sorption capacity was related to carbon pore structure characteristics, and the temperature of oxidative carbon-surface treatment was optimized for enhanced ammonia-sorption performance.

  9. Issues on the production and electrochemical separation of oxygen from carbon dioxide

    NASA Technical Reports Server (NTRS)

    Kaloupis, P.; Sridhar, K. R.

    1991-01-01

    There is considerable interest in in-situ propellant manufacturing on the moon and Mars. One of the concepts of oxygen production that is being actively pursued is the processing of atmospheric carbon dioxide on Mars to produce oxygen by means of thermal decomposition and electrochemical separation. The key component of such a production facility is the electrochemical separation cell that filters out the oxygen from the gas mixture of carbon dioxide, carbon monoxide, and oxygen. Efficient design of the separation cell and the selection of electrolyte and electrode materials of superior performance for the cell would translate to significant reduction in the power requirement and the mass of the production facility. The objective is to develop the technology required to produce the cells in-house and test various electrolyte and electrode materials systematically until the optimal combination is found. An effective technique was developed for the fabrication of disk shaped cells. Zirconia and Ceria cells were made in-house. Complete modules of the electrochemical cell and housings were designed, fabricated, and tested.

  10. Slurried solid media for simultaneous water purification and carbon dioxide removal from gas mixtures

    DOEpatents

    Aines, Roger D.; Bourcier, William L.; Viani, Brian

    2013-01-29

    A slurried solid media for simultaneous water purification and carbon dioxide removal from gas mixtures includes the steps of dissolving the gas mixture and carbon dioxide in water providing a gas, carbon dioxide, water mixture; adding a porous solid media to the gas, carbon dioxide, water mixture forming a slurry of gas, carbon dioxide, water, and porous solid media; heating the slurry of gas, carbon dioxide, water, and porous solid media producing steam; and cooling the steam to produce purified water and carbon dioxide.

  11. Non-conventional approaches to food processing in CELSS, 1. Algal proteins: Characterization and process optimization

    NASA Technical Reports Server (NTRS)

    Nakhost, Z.; Karel, M.; Krukonis, V. J.

    1987-01-01

    Protein isolate obtained from green algae cultivated under controlled conditions was characterized. Molecular weight determination of fractionated algal proteins using SDS-polyacrylamide gel electrophoresis revealed a wide spectrum of molecular weights ranging from 15,000 to 220,000. Isoelectric points of dissociated proteins were in the range of 3.95 to 6.20. Amino acid composition of protein isolate compared favorably with FAO standards. High content of essential amino acids leucine, valine, phenylalanine and lysine make algal protein isolate a high quality component of closed ecological life support system diets. To optimize the removal of algal lipids and pigments supercritical carbon dioxide extraction (with and without ethanol as a co-solvent) was used. Addition of ethanol to supercritical carbon dioxide resulted in more efficient removal of algal lipids and produced protein isolate with a good yield and protein recovery. The protein isolate extracted by the above mixture had an improved water solubility.

  12. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Dr. T. Nakamura; Dr. Miguel Olaizola; Dr. Stephen M. Masutani

    Most of the anthropogenic emissions of carbon dioxide result from the combustion of fossil fuels for energy production. Photosynthesis has long been recognized as a means, at least in theory, to sequester anthropogenic carbon dioxide. Aquatic microalgae have been identified as fast growing species whose carbon fixing rates are higher than those of land-based plants by one order of magnitude. Physical Sciences Inc. (PSI), Aquasearch, and the Hawaii Natural Energy Institute at the University of Hawaii are jointly developing technologies for recovery and sequestration of CO{sub 2} from stationary combustion systems by photosynthesis of microalgae. The research is aimed primarilymore » at demonstrating the ability of selected species of microalgae to effectively fix carbon from typical power plant exhaust gases. This report is the summary first year report covering the reporting period 1 October 2000 to 30 September 2001 in which PSI, Aquasearch and University of Hawaii conducted their tasks. Based on the work conducted during the previous reporting period, PSI initiated work on the component optimization work. Aquasearch continued their effort on selection of microalgae suitable for CO{sub 2} sequestration. University of Hawaii initiated effort on system optimization of the CO{sub 2} sequestration system.« less

  13. Understanding the Phase Behavior of Tetrahydrofuran + Carbon Dioxide, + Methane, and + Water Binary Mixtures from the SAFT-VR Approach.

    PubMed

    Míguez, J M; Piñeiro, M M; Algaba, J; Mendiboure, B; Torré, J P; Blas, F J

    2015-11-05

    The high-pressure phase diagrams of the tetrahydrofuran(1) + carbon dioxide(2), + methane(2), and + water(2) mixtures are examined using the SAFT-VR approach. Carbon dioxide molecule is modeled as two spherical segments tangentially bonded, water is modeled as a spherical segment with four associating sites to represent the hydrogen bonding, methane is represented as an isolated sphere, and tetrahydrofuran is represented as a chain of m tangentially bonded spherical segments. Dispersive interactions are modeled using the square-well intermolecular potential. In addition, two different molecular model mixtures are developed to take into account the subtle balance between water-tetrahydrofuran hydrogen-bonding interactions. The polar and quadrupolar interactions present in water, tetrahydrofuran, and carbon dioxide are treated in an effective way via square-well potentials of variable range. The optimized intermolecular parameters are taken from the works of Giner et al. (Fluid Phase Equil. 2007, 255, 200), Galindo and Blas (J. Phys. Chem. B 2002, 106, 4503), Patel et al. (Ind. Eng. Chem. Res. 2003, 42, 3809), and Clark et al. (Mol. Phys. 2006, 104, 3561) for tetrahydrofuran, carbon dioxide, methane, and water, respectively. The phase diagrams of the binary mixtures exhibit different types of phase behavior according to the classification of van Konynenburg and Scott, ranging from types I, III, and VI phase behavior for the tetrahydrofuran(1) + carbon dioxide(2), + methane(2), and + water(2) binary mixtures, respectively. This last type is characterized by the presence of a Bancroft point, positive azeotropy, and the so-called closed-loop curves that represent regions of liquid-liquid immiscibility in the phase diagram. The system exhibits lower critical solution temperatures (LCSTs), which denote the lower limit of immiscibility together with upper critical solution temperatures (UCSTs). This behavior is explained in terms of competition between the incompatibility with the alkyl parts of the tetrahydrofuran ring chain and the hydrogen bonding between water and the ether group. A minimum number of unlike interaction parameters are fitted to give the optimal representation of the most representative features of the binary phase diagrams. In the particular case of tetrahydrofuran(1) + water(2), two sets of intermolecular potential model parameters are proposed to describe accurately either the hypercritical point associated with the closed-loop liquid-liquid immiscibility region or the location of the mixture lower- and upper-critical end-points. The theory is not only able to predict the type of phase behavior of each mixture, but also provides a reasonably good description of the global phase behavior whenever experimental data are available.

  14. HYNOL PROCESS EVALUATION

    EPA Science Inventory

    The report examines process alternatives for the optimal use of natural gas and biomass for production of fuel-cell vehicle fuel, emphasizing maximum displacement of petroleum and maximum reduction of overall fuel-cycle carbon dioxide (CO2) emissions at least cost. Three routes a...

  15. Blood pressure long term regulation: A neural network model of the set point development

    PubMed Central

    2011-01-01

    Background The notion of the nucleus tractus solitarius (NTS) as a comparator evaluating the error signal between its rostral neural structures (RNS) and the cardiovascular receptor afferents into it has been recently presented. From this perspective, stress can cause hypertension via set point changes, so offering an answer to an old question. Even though the local blood flow to tissues is influenced by circulating vasoactive hormones and also by local factors, there is yet significant sympathetic control. It is well established that the state of maturation of sympathetic innervation of blood vessels at birth varies across animal species and it takes place mostly during the postnatal period. During ontogeny, chemoreceptors are functional; they discharge when the partial pressures of oxygen and carbon dioxide in the arterial blood are not normal. Methods The model is a simple biological plausible adaptative neural network to simulate the development of the sympathetic nervous control. It is hypothesized that during ontogeny, from the RNS afferents to the NTS, the optimal level of each sympathetic efferent discharge is learned through the chemoreceptors' feedback. Its mean discharge leads to normal oxygen and carbon dioxide levels in each tissue. Thus, the sympathetic efferent discharge sets at the optimal level if, despite maximal drift, the local blood flow is compensated for by autoregulation. Such optimal level produces minimum chemoreceptor output, which must be maintained by the nervous system. Since blood flow is controlled by arterial blood pressure, the long-term mean level is stabilized to regulate oxygen and carbon dioxide levels. After development, the cardiopulmonary reflexes play an important role in controlling efferent sympathetic nerve activity to the kidneys and modulating sodium and water excretion. Results Starting from fixed RNS afferents to the NTS and random synaptic weight values, the sympathetic efferents converged to the optimal values. When learning was completed, the output from the chemoreceptors became zero because the sympathetic efferents led to normal partial pressures of oxygen and carbon dioxide. Conclusions We introduce here a simple simulating computational theory to study, from a neurophysiologic point of view, the sympathetic development of cardiovascular regulation due to feedback signals sent off by cardiovascular receptors. The model simulates, too, how the NTS, as emergent property, acts as a comparator and how its rostral afferents behave as set point. PMID:21693057

  16. Measurement of carbon capture efficiency and stored carbon leakage

    DOEpatents

    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.

  17. Carbon Dioxide Embolism during Laparoscopic Surgery

    PubMed Central

    Park, Eun Young; Kwon, Ja-Young

    2012-01-01

    Clinically significant carbon dioxide embolism is a rare but potentially fatal complication of anesthesia administered during laparoscopic surgery. Its most common cause is inadvertent injection of carbon dioxide into a large vein, artery or solid organ. This error usually occurs during or shortly after insufflation of carbon dioxide into the body cavity, but may result from direct intravascular insufflation of carbon dioxide during surgery. Clinical presentation of carbon dioxide embolism ranges from asymptomatic to neurologic injury, cardiovascular collapse or even death, which is dependent on the rate and volume of carbon dioxide entrapment and the patient's condition. We reviewed extensive literature regarding carbon dioxide embolism in detail and set out to describe the complication from background to treatment. We hope that the present work will improve our understanding of carbon dioxide embolism during laparoscopic surgery. PMID:22476987

  18. Optimization of Location–Routing Problem for Cold Chain Logistics Considering Carbon Footprint

    PubMed Central

    Wang, Songyi; Tao, Fengming; Shi, Yuhe

    2018-01-01

    In order to solve the optimization problem of logistics distribution system for fresh food, this paper provides a low-carbon and environmental protection point of view, based on the characteristics of perishable products, and combines with the overall optimization idea of cold chain logistics distribution network, where the green and low-carbon location–routing problem (LRP) model in cold chain logistics is developed with the minimum total costs as the objective function, which includes carbon emission costs. A hybrid genetic algorithm with heuristic rules is designed to solve the model, and an example is used to verify the effectiveness of the algorithm. Furthermore, the simulation results obtained by a practical numerical example show the applicability of the model while provide green and environmentally friendly location-distribution schemes for the cold chain logistics enterprise. Finally, carbon tax policies are introduced to analyze the impact of carbon tax on the total costs and carbon emissions, which proves that carbon tax policy can effectively reduce carbon dioxide emissions in cold chain logistics network. PMID:29316639

  19. Modeling and optimization of proton-conducting solid oxide electrolysis cell: Conversion of CO2 into value-added products

    NASA Astrophysics Data System (ADS)

    Namwong, Lawit; Authayanun, Suthida; Saebea, Dang; Patcharavorachot, Yaneeporn; Arpornwichanop, Amornchai

    2016-11-01

    Proton-conducting solid oxide electrolysis cells (SOEC-H+) are a promising technology that can utilize carbon dioxide to produce syngas. In this work, a detailed electrochemical model was developed to predict the behavior of SOEC-H+ and to prove the assumption that the syngas is produced through a reversible water gas-shift (RWGS) reaction. The simulation results obtained from the model, which took into account all of the cell voltage losses (i.e., ohmic, activation, and concentration losses), were validated using experimental data to evaluate the unknown parameters. The developed model was employed to examine the structural and operational parameters. It is found that the cathode-supported SOEC-H+ is the best configuration because it requires the lowest cell potential. SOEC-H+ operated favorably at high temperatures and low pressures. Furthermore, the simulation results revealed that the optimal S/C molar ratio for syngas production, which can be used for methanol synthesis, is approximately 3.9 (at a constant temperature and pressure). The SOEC-H+ was optimized using a response surface methodology, which was used to determine the optimal operating conditions to minimize the cell potential and maximize the carbon dioxide flow rate.

  20. Optimization of supercritical fluid extraction and HPLC identification of wedelolactone from Wedelia calendulacea by orthogonal array design.

    PubMed

    Patil, Ajit A; Sachin, Bhusari S; Wakte, Pravin S; Shinde, Devanand B

    2014-11-01

    The purpose of this work is to provide a complete study of the influence of operational parameters of the supercritical carbon dioxide assisted extraction (SC CO2E) on yield of wedelolactone from Wedelia calendulacea Less., and to find an optimal combination of factors that maximize the wedelolactone yield. In order to determine the optimal combination of the four factors viz. operating pressure, temperature, modifier concentration and extraction time, a Taguchi experimental design approach was used: four variables (three levels) in L9 orthogonal array. Wedelolactone content was determined using validated HPLC methodology. Optimum extraction conditions were found to be as follows: extraction pressure, 25 MPa; temperature, 40 °C; modifier concentration, 10% and extraction time, 90 min. Optimum extraction conditions demonstrated wedelolactone yield of 8.01 ± 0.34 mg/100 g W. calendulacea Less. Pressure, temperature and time showed significant (p < 0.05) effect on the wedelolactone yield. The supercritical carbon dioxide extraction showed higher selectivity than the conventional Soxhlet assisted extraction method.

  1. Optimization of supercritical fluid extraction and HPLC identification of wedelolactone from Wedelia calendulacea by orthogonal array design

    PubMed Central

    Patil, Ajit A.; Sachin, Bhusari S.; Wakte, Pravin S.; Shinde, Devanand B.

    2013-01-01

    The purpose of this work is to provide a complete study of the influence of operational parameters of the supercritical carbon dioxide assisted extraction (SC CO2E) on yield of wedelolactone from Wedelia calendulacea Less., and to find an optimal combination of factors that maximize the wedelolactone yield. In order to determine the optimal combination of the four factors viz. operating pressure, temperature, modifier concentration and extraction time, a Taguchi experimental design approach was used: four variables (three levels) in L9 orthogonal array. Wedelolactone content was determined using validated HPLC methodology. Optimum extraction conditions were found to be as follows: extraction pressure, 25 MPa; temperature, 40 °C; modifier concentration, 10% and extraction time, 90 min. Optimum extraction conditions demonstrated wedelolactone yield of 8.01 ± 0.34 mg/100 g W. calendulacea Less. Pressure, temperature and time showed significant (p < 0.05) effect on the wedelolactone yield. The supercritical carbon dioxide extraction showed higher selectivity than the conventional Soxhlet assisted extraction method. PMID:25687584

  2. Research Progress in Carbon Dioxide Storage and Enhanced Oil Recovery

    NASA Astrophysics Data System (ADS)

    Wang, Keliang; Wang, Gang; Lu, Chunjing

    2018-02-01

    With the rapid development of global economy, human beings have become highly dependent upon fossil fuel such as coal and petroleum. Much fossil fuel is consumed in industrial production and human life. As a result, carbon dioxide emissions have been increasing, and the greenhouse effects thereby generated are posing serious threats to environment of the earth. These years, increasing average global temperature, frequent extreme weather events and climatic changes cause material disasters to the world. After scientists’ long-term research, ample evidences have proven that emissions of greenhouse gas like carbon dioxide have brought about tremendous changes to global climate. To really reduce carbon dioxide emissions, governments of different countries and international organizations have invested much money and human resources in performing research related to carbon dioxide emissions. Manual underground carbon dioxide storage and carbon dioxide-enhanced oil recovery are schemes with great potential and prospect for reducing carbon dioxide emissions. Compared with other schemes for reducing carbon dioxide emissions, aforementioned two schemes exhibit high storage capacity and yield considerable economic benefits, so they have become research focuses for reducing carbon dioxide emissions. This paper introduces the research progress in underground carbon dioxide storage and enhanced oil recovery, pointing out the significance and necessity of carbon dioxide-driven enhanced oil recovery.

  3. Algae Derived Biofuel

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Jahan, Kauser

    One of the most promising fuel alternatives is algae biodiesel. Algae reproduce quickly, produce oils more efficiently than crop plants, and require relatively few nutrients for growth. These nutrients can potentially be derived from inexpensive waste sources such as flue gas and wastewater, providing a mutual benefit of helping to mitigate carbon dioxide waste. Algae can also be grown on land unsuitable for agricultural purposes, eliminating competition with food sources. This project focused on cultivating select algae species under various environmental conditions to optimize oil yield. Membrane studies were also conducted to transfer carbon di-oxide more efficiently. An LCA studymore » was also conducted to investigate the energy intensive steps in algae cultivation.« less

  4. Pd-Pt and Fe-Ni nanoparticles formed by covalent molecular assembly in supercritical carbon dioxide.

    PubMed

    Puniredd, Sreenivasa Reddy; Weiyi, Seah; Srinivasan, M P

    2008-04-01

    We report the formation of Pd-Pt nanoparticles within a dendrimer-laden ultrathin film matrix immobilized on a solid support and constructed by covalent layer-by-layer (LbL) assembly using supercritical carbon dioxide (SCCO2) as the processing medium. Particle size distribution and composition were controlled by precursor composition. The precursor compositions are optimized for Pd-Pt nanoparticles and later extended to the formation of Fe-Ni nanoparticles. As an example of the application of nanoparticles in tribology, Fe-Ni nanoparticle-laden films were observed to exhibit better tribological properties than those containing the monometallic species, thereby suggesting that combination of nanoparticles can be used to derive greater benefits.

  5. [Plant responses to elevated atmospheric carbon dioxide and transmission to other trophic levels]. Progress report, May 1991, DOE Grant DE-FG09-84ER60255

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Lincoln, D.E.

    1991-05-01

    Experiments were performed to determine the effects of carbon dioxide on plants and on the insects feeding on these plants. Current progress is reported for the following experiments: Response of a Specialist-Feeding Insect Herbivore to Carbon Dioxide Induced Changes in Its Hostplant; Growth and Reproduction of Grasshoppers Feeding on a C{sub 4} Grass Under Elevated Carbon Dioxide; Elevated Carbon Dioxide and Temperature Effects on Growth and Defense of Big Sagebrush; Sagebrush and Grasshopper Responses to Atmospheric Carbon Dioxide Concentration; Biomass Allocation Patterns of Defoliated Sagebrush Grown Under Two Levels of Carbon Dioxide; and Sagebrush Carbon Allocation Patterns and Grasshopper Nutrition:more » The Influence of Carbon Dioxide Enrichment and Soil Mineral Limitation.« less

  6. 21 CFR 868.1400 - Carbon dioxide gas analyzer.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Carbon dioxide gas analyzer. 868.1400 Section 868...) MEDICAL DEVICES ANESTHESIOLOGY DEVICES Diagnostic Devices § 868.1400 Carbon dioxide gas analyzer. (a) Identification. A carbon dioxide gas analyzer is a device intended to measure the concentration of carbon dioxide...

  7. 21 CFR 868.1400 - Carbon dioxide gas analyzer.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Carbon dioxide gas analyzer. 868.1400 Section 868...) MEDICAL DEVICES ANESTHESIOLOGY DEVICES Diagnostic Devices § 868.1400 Carbon dioxide gas analyzer. (a) Identification. A carbon dioxide gas analyzer is a device intended to measure the concentration of carbon dioxide...

  8. 46 CFR 108.627 - Carbon dioxide alarm.

    Code of Federal Regulations, 2010 CFR

    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 to...

  9. 46 CFR 169.732 - Carbon dioxide alarm.

    Code of Federal Regulations, 2010 CFR

    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.” ...

  10. 46 CFR 35.40-7 - Carbon dioxide alarm-T/ALL.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 1 2010-10-01 2010-10-01 false Carbon dioxide alarm-T/ALL. 35.40-7 Section 35.40-7... Requirements-TB/ALL. § 35.40-7 Carbon dioxide alarm—T/ALL. Adjacent to all carbon dioxide fire extinguishing... AT ONCE. CARBON DIOXIDE BEING RELEASED.” ...

  11. 21 CFR 868.1400 - Carbon dioxide gas analyzer.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Carbon dioxide gas analyzer. 868.1400 Section 868...) MEDICAL DEVICES ANESTHESIOLOGY DEVICES Diagnostic Devices § 868.1400 Carbon dioxide gas analyzer. (a) Identification. A carbon dioxide gas analyzer is a device intended to measure the concentration of carbon dioxide...

  12. 46 CFR 169.732 - Carbon dioxide alarm.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 7 2011-10-01 2011-10-01 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.” ...

  13. 21 CFR 868.1400 - Carbon dioxide gas analyzer.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Carbon dioxide gas analyzer. 868.1400 Section 868...) MEDICAL DEVICES ANESTHESIOLOGY DEVICES Diagnostic Devices § 868.1400 Carbon dioxide gas analyzer. (a) Identification. A carbon dioxide gas analyzer is a device intended to measure the concentration of carbon dioxide...

  14. 21 CFR 862.1160 - Bicarbonate/carbon dioxide test system.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Bicarbonate/carbon dioxide test system. 862.1160... Systems § 862.1160 Bicarbonate/carbon dioxide test system. (a) Identification. A bicarbonate/carbon dioxide test system is a device intended to measure bicarbonate/carbon dioxide in plasma, serum, and whole...

  15. Carbon dioxide production during cardiopulmonary bypass: pathophysiology, measure and clinical relevance.

    PubMed

    Ranucci, Marco; Carboni, Giovanni; Cotza, Mauro; de Somer, Filip

    2017-01-01

    Carbon dioxide production during cardiopulmonary bypass derives from both the aerobic metabolism and the buffering of lactic acid produced by tissues under anaerobic conditions. Therefore, carbon dioxide removal monitoring is an important measure of the adequacy of perfusion and oxygen delivery. However, routine monitoring of carbon dioxide removal is not widely applied. The present article reviews the main physiological and pathophysiological sources of carbon dioxide, the available techniques to assess carbon dioxide production and removal and the clinically relevant applications of carbon dioxide-related variables as markers of the adequacy of perfusion during cardiopulmonary bypass.

  16. Carbon dioxide mineralization process design and evaluation: concepts, case studies, and considerations.

    PubMed

    Yuen, Yeo Tze; Sharratt, Paul N; Jie, Bu

    2016-11-01

    Numerous carbon dioxide mineralization (CM) processes have been proposed to overcome the slow rate of natural weathering of silicate minerals. Ten of these proposals are mentioned in this article. The proposals are described in terms of the four major areas relating to CM process design: pre-treatment, purification, carbonation, and reagent recycling operations. Any known specifics based on probable or representative operating and reaction conditions are listed, and basic analysis of the strengths and shortcomings associated with the individual process designs are given in this article. The processes typically employ physical or chemical pseudo-catalytic methods to enhance the rate of carbon dioxide mineralization; however, both methods have its own associated advantages and problems. To examine the feasibility of a CM process, three key aspects should be included in the evaluation criteria: energy use, operational considerations as well as product value and economics. Recommendations regarding the optimal level of emphasis and implementation of measures to control these aspects are given, and these will depend very much on the desired process objectives. Ultimately, a mix-and-match approach to process design might be required to provide viable and economic proposals for CM processes.

  17. Analysis of methane biodegradation by Methylosinus trichosporium OB3b

    PubMed Central

    Rodrigues, Andréa dos Santos; Salgado, Belkis Valdman e Andréa Medeiros

    2009-01-01

    The microbial oxidation of methane in the atmosphere is performed by methanotrophic bacteria that use methane as a unique source of carbon and energy. The objective of this work consisted of the investigation of the best conditions of methane biodegradation by methanotrophic bacteria Methylosinus trichosporium OB3b that oxidize it to carbon dioxide, and the use of these microorganisms in monitoring methods for methane. The results showed that M. trichosporium OB3b was capable to degrade methane in a more effective way with an initial microorganism concentration of 0.0700 g.L-1, temperature of 30ºC, pH 6.5 and using 1.79 mmol of methane. In these same conditions, there was no bacterial growth when 2.69 mmol of methane was used. The specific rate of microorganism growth, the conversion factor, the efficiency and the volumetric productivity, for the optimized conditions of biodegradation were, respectively, 0.0324 h-1, 0.6830 gcells/gCH4, 73.73% and 2.7732.10-3 gcells/L.h. The final product of methane microbiological degradation, carbon dioxide, was quantified through the use of a commercial electrode, and, through this, the grade of methane conversion in carbon dioxide was calculated. PMID:24031362

  18. 46 CFR 35.40-8 - Carbon dioxide warning signs-T/ALL.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 1 2014-10-01 2014-10-01 false Carbon dioxide warning signs-T/ALL. 35.40-8 Section 35... Marking Requirements-TB/ALL § 35.40-8 Carbon dioxide warning signs—T/ALL. Each entrance to a space storing carbon dioxide cylinders, a space protected by carbon dioxide systems, or any space into which carbon...

  19. 46 CFR 35.40-8 - Carbon dioxide warning signs-T/ALL.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 1 2013-10-01 2013-10-01 false Carbon dioxide warning signs-T/ALL. 35.40-8 Section 35... Marking Requirements-TB/ALL § 35.40-8 Carbon dioxide warning signs—T/ALL. Each entrance to a space storing carbon dioxide cylinders, a space protected by carbon dioxide systems, or any space into which carbon...

  20. Visual and reversible carbon dioxide sensing enabled by doctor blade coated macroporous photonic crystals.

    PubMed

    Lin, Yi-Han; Suen, Shing-Yi; Yang, Hongta

    2017-11-15

    With significant impacts of carbon dioxide on global climate change, carbon dioxide sensing is of great importance. However, most of the existing sensing technologies are prone to interferences from carbon monoxide, or suffer from the use of sophisticated instruments. This research reports the development of reproducible carbon dioxide sensor using roll-to-roll compatible doctor blade coated three-dimensional macroporous photonic crystals. The pores are functionalized with amine groups to allow the reaction with carbon dioxide in the presence of humidity. The adsorption of carbon dioxide leads to red-shift and amplitude reduction of the optical stop bands, resulting in carbon dioxide detection with visible readout. The dependences of the diffraction wavelength on carbon dioxide partial pressure for various amine-functionalized photonic crystals and different humidities in the environment are systematically investigated. In addition, the reproducibility of carbon dioxide sensing has also been demonstrated in this research. Copyright © 2017 Elsevier Inc. All rights reserved.

  1. 46 CFR 78.47-9 - Carbon dioxide alarm.

    Code of Federal Regulations, 2010 CFR

    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) [Reserved] ...

  2. 46 CFR 196.37-9 - Carbon dioxide alarm.

    Code of Federal Regulations, 2010 CFR

    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 BEING...

  3. 46 CFR 76.15-20 - Carbon dioxide storage.

    Code of Federal Regulations, 2010 CFR

    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 the...

  4. 46 CFR 97.37-9 - Carbon dioxide alarm.

    Code of Federal Regulations, 2010 CFR

    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 BEING...

  5. 49 CFR 195.4 - Compatibility necessary for transportation of hazardous liquids or carbon dioxide.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... hazardous liquids or carbon dioxide. 195.4 Section 195.4 Transportation Other Regulations Relating to... necessary for transportation of hazardous liquids or carbon dioxide. No person may transport any hazardous liquid or carbon dioxide unless the hazardous liquid or carbon dioxide is chemically compatible with both...

  6. 46 CFR 196.37-9 - Carbon dioxide alarm.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 7 2011-10-01 2011-10-01 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 BEING...

  7. 49 CFR 195.4 - Compatibility necessary for transportation of hazardous liquids or carbon dioxide.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... hazardous liquids or carbon dioxide. 195.4 Section 195.4 Transportation Other Regulations Relating to... necessary for transportation of hazardous liquids or carbon dioxide. No person may transport any hazardous liquid or carbon dioxide unless the hazardous liquid or carbon dioxide is chemically compatible with both...

  8. Engineering a synthetic pathway in cyanobacteria for isopropanol production directly from carbon dioxide and light.

    PubMed

    Kusakabe, Tamami; Tatsuke, Tsuneyuki; Tsuruno, Keigo; Hirokawa, Yasutaka; Atsumi, Shota; Liao, James C; Hanai, Taizo

    2013-11-01

    Production of alternate fuels or chemicals directly from solar energy and carbon dioxide using engineered cyanobacteria is an attractive method to reduce petroleum dependency and minimize carbon emissions. Here, we constructed a synthetic pathway composed of acetyl-CoA acetyl transferase (encoded by thl), acetoacetyl-CoA transferase (encoded by atoAD), acetoacetate decarboxylase (encoded by adc) and secondary alcohol dehydrogenase (encoded by adh) in Synechococcus elongatus strain PCC 7942 to produce isopropanol. The enzyme-coding genes, heterogeneously originating from Clostridium acetobutylicum ATCC 824 (thl and adc), Escherichia coli K-12 MG1655 (atoAD) and Clostridium beijerinckii (adh), were integrated into the S. elongatus genome. Under the optimized production conditions, the engineered cyanobacteria produced 26.5 mg/L of isopropanol after 9 days. © 2013 Published by Elsevier Inc.

  9. NASA Carbon Sleuth Begins Year Two

    NASA Image and Video Library

    2015-10-29

    Global average carbon dioxide concentrations as seen by NASA’s Orbiting Carbon Observatory-2 mission, June 1-15, 2015. OCO-2 measures carbon dioxide from the top of Earth's atmosphere to its surface. Higher carbon dioxide concentrations are in red, with lower concentrations in yellows and greens. Scientists poring over data from OCO-2 mission are seeing patterns emerge as they seek answers to questions about atmospheric carbon dioxide. Among the most striking features visible in the first year of OCO-2 data is the increase in carbon dioxide in the northern hemisphere during winter, when trees are not removing carbon dioxide, followed by its decrease in spring, as trees start to grow and remove carbon dioxide from the atmosphere. http://photojournal.jpl.nasa.gov/catalog/PIA20039

  10. The Economics of Carbon Dioxide Removal: The Case against Free Disposal

    NASA Astrophysics Data System (ADS)

    Keller, D. P.; Rickels, W.; Quaas, M.; Oschlies, A.; Reith, F.

    2016-12-01

    Facing the challenge to keep the average global temperature increase below 2°C and to limit long-term climate change, removing carbon dioxide from the atmosphere (Carbon Dioxide Removal, CDR) and disposing of it in non-atmospheric carbon reservoirs is becoming increasingly necessary. The social cost of removing carbon into the terrestrial biosphere (e.g. by afforestation) or the ocean (e.g. by spreading olivine in coastal areas) arises from carbon-cycle feedbacks and saturation effects. Yet they are ignored in existing economic studies on CDR. Neglecting non-atmospheric social cost results in inconsistent estimates with regard to the share and timing of CDR measures in climate policy. Here, we use an intermediate-complexity earth system model, the University of Victoria (UVic) model, to calibrate a dynamic economic model, capturing the temperature feedback and saturation effect of terrestrial carbon uptake and the saturation effect of oceanic carbon uptake to obtain an improved understanding of the net social carbon value of terrestrial and oceanic CDR. We show that planning horizons beyond the year 2100 are required to properly reflect long-term scarcity issues of non-atmospheric carbon reservoirs in current carbon prices and that neglecting non-atmospheric social cost results in too low abatement efforts and in turn in too large and earlier application of CDR measures than if applied optimally. The figure shows the carbon prices for the different carbon reservoirs in the year 2100 in dependence of the planning horizon (for a climate policy aiming to limit global mean temperature increase to 2°C). The difference between the atmospheric and the non-atmospheric carbon prices indicates the benefits of the different CDR options.

  11. Optimization of supercritical carbon dioxide extraction of Piper Betel Linn leaves oil and total phenolic content

    NASA Astrophysics Data System (ADS)

    Aziz, A. H. A.; Yunus, M. A. C.; Arsad, N. H.; Lee, N. Y.; Idham, Z.; Razak, A. Q. A.

    2016-11-01

    Supercritical Carbon Dioxide (SC-CO2) Extraction was applied to extract piper betel linn leaves. The piper betel leaves oil was used antioxidant, anti-diabetic, anticancer and antistroke. The aim of this study was to optimize the conditions of pressure, temperature and flowrate for oil yield and total phenolic content. The operational conditions of SC-CO2 studied were pressure (10, 20, 30 MPa), temperature (40, 60, 80 °C) and flowrate carbon dioxide (4, 6, 8 mL/min). The constant parameters were average particle size and extraction regime, 355pm and 3.5 hours respectively. First order polynomial expression was used to express the extracted oil while second order polynomial expression was used to express the total phenolic content and the both results were satisfactory. The best conditions to maximize the total extraction oil yields and total phenolic content were 30 MPa, 80 °C and 4.42 mL/min leading to 7.32% of oil and 29.72 MPa, 67.53 °C and 7.98 mL/min leading to 845.085 mg GAE/g sample. In terms of optimum condition with high extraction yield and high total phenolic content in the extracts, the best operating conditions were 30 MPa, 78 °C and 8 mL/min with 7.05% yield and 791.709 mg gallic acid equivalent (GAE)/g sample. The most dominant condition for extraction of oil yield and phenolic content were pressure and CO2 flowrate. The results show a good fit to the proposed model and the optimal conditions obtained were within the experimental range with the value of R2 was 96.13% for percentage yield and 98.52% for total phenolic content.

  12. Carbon dioxide separation using adsorption with steam regeneration

    DOEpatents

    Elliott, Jeannine Elizabeth; Copeland, Robert James; Leta, Daniel P.; McCall, Patrick P.; Bai, Chuansheng; DeRites, Bruce A.

    2016-11-29

    A process for separating a carbon dioxide from a gas stream is disclosed. The process can include passing the gas stream over a sorbent that adsorbs the carbon dioxide by concentration swing adsorption and adsorptive displacement. The sorbent can be regenerated and the carbon dioxide recaptured by desorbing the carbon dioxide from the sorbent using concentration swing adsorption and desorptive displacement. A carbon dioxide separation system is also disclosed. Neither the system nor the process rely on temperature swing or pressure swing adsorption.

  13. Measuring the Spectral Expression of Carbon Dioxide in the Solar Reflected Spectrum with AVIRIS

    NASA Technical Reports Server (NTRS)

    Green, Robert O.

    2001-01-01

    Carbon dioxide is a low-concentration, but important, component of the Earth's atmosphere. This gas absorbs electromagnetic radiation (EMR) in several regions of the spectrum. Absorption of energy by carbon dioxide adds heat to the atmosphere. In the world today, the burning of fossil fuels and other anthropogenic processes adds carbon dioxide to the atmosphere. Other natural processes in the Earth's system both add and remove carbon dioxide. Overall, measurements of atmospheric carbon dioxide at selected sites around the globe show an increased carbon dioxide concentration in the atmosphere. A figure shows the measured carbon dioxide from Mauna Loa, Hawaii, from 1958 to 2000. Overall, the concentration has increased from 315 to 365 ppm at this site over this period. (There is also a yearly cycle to the concentration that is timed with and hypothesized to be related to the vegetation growing season in the Northern Hemisphere.) The overall expected effect of this increase of atmospheric carbon dioxide is trapping of heat in the atmosphere and global warming. While this overall relationship between carbon dioxide and global warming seems straightforward, many of the specific details relating to regional and local sources and sinks and gradients of carbon dioxide are not well understood. A remote sensing capability to measure carbon dioxide could provide important inputs for scientific research to better understand the distribution and change in atmospheric carbon dioxide at detailed spatial and temporal levels. In pursuit of this remote sensing of carbon dioxide objective, this paper analyzes the expression of carbon dioxide in the spectral range measured by the Airborne Visible/Infrared Imagery Spectrometer (AVIRIS). Based on these analyses, a spectral-fitting algorithm that uses AVIRIS measured spectra and MODTRAN radiative-transfer code modeled spectra to derive total column carbon dioxide abundance has been developed. This algorithm has been applied to an AVIRIS data set acquired over Pasadena, California, in 1999 and a data set acquired over the Pacific Ocean near Hawaii in 2000 with promising results. This is ongoing research; the current initial analyses, measurements, and results are reported in this paper.

  14. 21 CFR 184.1240 - Carbon dioxide.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 3 2014-04-01 2014-04-01 false Carbon dioxide. 184.1240 Section 184.1240 Food and....1240 Carbon dioxide. (a) Carbon dioxide (empirical formula CO2, CAS Reg. No. 124-38-9) occurs as a..., sublimes under atmospheric pressure at a temperature of −78.5 °C. Carbon dioxide is prepared as a byproduct...

  15. 49 CFR 173.217 - Carbon dioxide, solid (dry ice).

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 2 2011-10-01 2011-10-01 false Carbon dioxide, solid (dry ice). 173.217 Section... Class 7 § 173.217 Carbon dioxide, solid (dry ice). (a) Carbon dioxide, solid (dry ice), when offered for... marked on two sides “WARNING CO2 SOLID (DRY ICE).” (2) Other packagings containing solid carbon dioxide...

  16. 49 CFR 173.217 - Carbon dioxide, solid (dry ice).

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 2 2012-10-01 2012-10-01 false Carbon dioxide, solid (dry ice). 173.217 Section... Class 7 § 173.217 Carbon dioxide, solid (dry ice). (a) Carbon dioxide, solid (dry ice), when offered for... marked on two sides “WARNING CO2 SOLID (DRY ICE).” (2) Other packagings containing solid carbon dioxide...

  17. 49 CFR 173.217 - Carbon dioxide, solid (dry ice).

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 2 2010-10-01 2010-10-01 false Carbon dioxide, solid (dry ice). 173.217 Section... Class 7 § 173.217 Carbon dioxide, solid (dry ice). (a) Carbon dioxide, solid (dry ice), when offered for... marked on two sides “WARNING CO2 SOLID (DRY ICE).” (2) Other packagings containing solid carbon dioxide...

  18. 49 CFR 173.217 - Carbon dioxide, solid (dry ice).

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 2 2014-10-01 2014-10-01 false Carbon dioxide, solid (dry ice). 173.217 Section... Class 7 § 173.217 Carbon dioxide, solid (dry ice). (a) Carbon dioxide, solid (dry ice), when offered for... marked on two sides “WARNING CO2 SOLID (DRY ICE).” (2) Other packagings containing solid carbon dioxide...

  19. 49 CFR 173.217 - Carbon dioxide, solid (dry ice).

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 2 2013-10-01 2013-10-01 false Carbon dioxide, solid (dry ice). 173.217 Section... Class 7 § 173.217 Carbon dioxide, solid (dry ice). (a) Carbon dioxide, solid (dry ice), when offered for... marked on two sides “WARNING CO2 SOLID (DRY ICE).” (2) Other packagings containing solid carbon dioxide...

  20. 27 CFR 24.245 - Use of carbon dioxide in still wine.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2011-04-01 2011-04-01 false Use of carbon dioxide in... Use of carbon dioxide in still wine. The addition of carbon dioxide to (and retention in) still wine... of carbon dioxide per 100 milliliters of wine or where the variation results from the use of methods...

  1. 46 CFR 108.431 - Carbon dioxide systems: General.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... Carbon dioxide systems: General. (a) Sections 108.431 through 108.457 apply to high pressure carbon dioxide fire extinguishing systems. (b) Low pressure systems, that is, those in which the carbon dioxide...

  2. Economic analysis of secondary and enhanced oil recovery techniques in Wyoming

    NASA Astrophysics Data System (ADS)

    Kara, Erdal

    This dissertation primarily aims to theoretically analyze a firm's optimization of enhanced oil recovery (EOR) and carbon dioxide sequestration under different social policies and empirically analyze the firm's optimization of enhanced oil recovery. The final part of the dissertation empirically analyzes how geological factors and water injection management influence oil recovery. The first chapter builds a theoretical model to analyze economic optimization of EOR and geological carbon sequestration under different social policies. Specifically, it analyzes how social policies on sequestration influence the extent of oil operations, optimal oil production and CO2 sequestration. The theoretical results show that the socially optimal policy is a subsidy on the net CO2 sequestration, assuming negative net emissions from EOR. Such a policy is expected to increase a firm's total carbon dioxide sequestration. The second chapter statistically estimates the theoretical oil production model and its different versions. Empirical results are not robust over different estimation techniques and not in line with the theoretical production model. The last part of the second chapter utilizes a simplified version of theoretical model and concludes that EOR via CO2 injection improves oil recovery. The final chapter analyzes how a contemporary oil recovery technology (water flooding of oil reservoirs) and various reservoir-specific geological factors influence oil recovery in Wyoming. The results show that there is a positive concave relationship between cumulative water injection and cumulative oil recovery and also show that certain geological factors affect the oil recovery. Moreover, the curvature of the concave functional relationship between cumulative water injection and oil recovery is reservoir-specific due to heterogeneities among different reservoirs.

  3. Carbon dioxide sequestration by chemolithotrophic oleaginous bacteria for production and optimization of polyhydroxyalkanoate.

    PubMed

    Kumar, Manish; Gupta, Asmita; Thakur, Indu Shekhar

    2016-08-01

    The present work involved screening of a previously reported carbon concentrating oleaginous bacterial strain Serratia sp. ISTD04 for production of PHA and optimization of process parameters for enhanced PHA and biomass generation. The selected bacterial strain was screened for PHA production based on Nile red staining followed by visualization under fluorescence microscope. Spectrofluorometric measurement of Nile red fluorescence of the bacterial culture was also done. Confirmatory analysis of PHA accumulation by GC-MS revealed the presence of 3-hydroxyvalerate. Detection of characteristic peaks in the FT-IR spectrum further confirmed the production of PHA by the bacterium. Response Surface Methodology was used for optimization of pH and carbon sources' concentrations for higher PHA production. There was almost a 2 fold increase in the production of PHA following optimization as compared to un-optimized condition. The study thus establishes the production of PHA by Serratia sp. ISTD04. Copyright © 2016 Elsevier Ltd. All rights reserved.

  4. Optimal function explains forest responses to global change

    Treesearch

    Roderick Dewar; Oskar Franklin; Annikki Makela; Ross E. McMurtrie; Harry T. Valentine

    2009-01-01

    Plant responses to global changes in carbon dioxide (CO2), nitrogen, and water availability are critical to future atmospheric CO2 concentrations, hydrology, and hence climate. Our understanding of those responses is incomplete, however. Multiple-resource manipulation experiments and empirical observations have revealed a...

  5. IMPROVEMENTS IN OR RELATING TO THE PRODUCTION OF SINTERED URANIUM DIOXIDE

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Russell, L.E.; Harrison, J.D.L.; Brett, N.H.

    A method is described for producing a dense sintered body of uranium dioxide or a mixture thereof with plutonium dioxide. Compacted uranium dioxide or a compacted uranium dioxide-plutonium dioxide mixture is heated to at least 1300 deg C in an atmosphere of carbon dioxide or carbon dioxide mixed with carbon monoxide. (R.J.S.)

  6. Designed amyloid fibers as materials for selective carbon dioxide capture

    PubMed Central

    Li, Dan; Furukawa, Hiroyasu; Deng, Hexiang; Liu, Cong; Yaghi, Omar M.; Eisenberg, David S.

    2014-01-01

    New materials capable of binding carbon dioxide are essential for addressing climate change. Here, we demonstrate that amyloids, self-assembling protein fibers, are effective for selective carbon dioxide capture. Solid-state NMR proves that amyloid fibers containing alkylamine groups reversibly bind carbon dioxide via carbamate formation. Thermodynamic and kinetic capture-and-release tests show the carbamate formation rate is fast enough to capture carbon dioxide by dynamic separation, undiminished by the presence of water, in both a natural amyloid and designed amyloids having increased carbon dioxide capacity. Heating to 100 °C regenerates the material. These results demonstrate the potential of amyloid fibers for environmental carbon dioxide capture. PMID:24367077

  7. 46 CFR 35.40-7 - Carbon dioxide and clean agent alarms-T/ALL.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 1 2013-10-01 2013-10-01 false Carbon dioxide and clean agent alarms-T/ALL. 35.40-7... Marking Requirements-TB/ALL § 35.40-7 Carbon dioxide and clean agent alarms—T/ALL. Each carbon dioxide or...: “WHEN ALARM SOUNDS VACATE AT ONCE. [CARBON DIOXIDE/CLEAN AGENT—as appropriate] BEING RELEASED.” [USCG...

  8. 27 CFR 24.245 - Use of carbon dioxide in still wine.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2013-04-01 2013-04-01 false Use of carbon dioxide in... Use of carbon dioxide in still wine. The addition of carbon dioxide to (and retention in) still wine... than 0.392 grams of carbon dioxide per 100 milliliters of wine. However, a tolerance of not more than 0...

  9. 46 CFR 35.40-7 - Carbon dioxide and clean agent alarms-T/ALL.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 1 2014-10-01 2014-10-01 false Carbon dioxide and clean agent alarms-T/ALL. 35.40-7... Marking Requirements-TB/ALL § 35.40-7 Carbon dioxide and clean agent alarms—T/ALL. Each carbon dioxide or...: “WHEN ALARM SOUNDS VACATE AT ONCE. [CARBON DIOXIDE/CLEAN AGENT—as appropriate] BEING RELEASED.” [USCG...

  10. Carbon dioxide dangers demonstration model

    USGS Publications Warehouse

    Venezky, Dina; Wessells, Stephen

    2010-01-01

    Carbon dioxide is a dangerous volcanic gas. When carbon dioxide seeps from the ground, it normally mixes with the air and dissipates rapidly. However, because carbon dioxide gas is heavier than air, it can collect in snowbanks, depressions, and poorly ventilated enclosures posing a potential danger to people and other living things. In this experiment we show how carbon dioxide gas displaces oxygen as it collects in low-lying areas. When carbon dioxide, created by mixing vinegar and baking soda, is added to a bowl with candles of different heights, the flames are extinguished as if by magic.

  11. Energy efficient solvent regeneration process for carbon dioxide capture

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Zhou, Shaojun; Meyer, Howard S.; Li, Shiguang

    A process for removing carbon dioxide from a carbon dioxide-loaded solvent uses two stages of flash apparatus. Carbon dioxide is flashed from the solvent at a higher temperature and pressure in the first stage, and a lower temperature and pressure in the second stage, and is fed to a multi-stage compression train for high pressure liquefaction. Because some of the carbon dioxide fed to the compression train is already under pressure, less energy is required to further compress the carbon dioxide to a liquid state, compared to conventional processes.

  12. Screen for Carbon Dioxide.

    ERIC Educational Resources Information Center

    Foster, John; And Others

    1986-01-01

    Presents a set of laboratory experiments that can assist students in the detection of carbon dioxide. Offers a variation of the supported drop method of carbon dioxide detection that provides readily visible positive results. Includes background information on carbon dioxide. (ML)

  13. Zeolites for CO2-CO-O2 Separation to Obtain CO2-Neutral Fuels.

    PubMed

    Perez-Carbajo, Julio; Matito-Martos, Ismael; Balestra, Salvador R G; Tsampas, Mihalis N; van de Sanden, Mauritius C M; Delgado, José A; Águeda, V Ismael; Merkling, Patrick J; Calero, Sofia

    2018-06-20

    Carbon dioxide release has become an important global issue due to the significant and continuous rise in atmospheric CO 2 concentrations and the depletion of carbon-based energy resources. Plasmolysis is a very energy-efficient process for reintroducing CO 2 into energy and chemical cycles by converting CO 2 into CO and O 2 utilizing renewable electricity. The bottleneck of the process is that CO remains mixed with O 2 and residual CO 2 . Therefore, efficient gas separation and recuperation are essential for obtaining pure CO, which, via water gas shift and Fischer-Tropsch reactions, can lead to the production of CO 2 -neutral fuels. The idea behind this work is to provide a separation mechanism based on zeolites to optimize the separation of carbon dioxide, carbon monoxide, and oxygen under mild operational conditions. To achieve this goal, we performed a thorough screening of available zeolites based on topology and adsorptive properties using molecular simulation and ideal adsorption solution theory. FAU, BRE, and MTW are identified as suitable topologies for these separation processes. FAU can be used for the separation of carbon dioxide from carbon monoxide and oxygen and BRE or MTW for the separation of carbon monoxide from oxygen. These results are reinforced by pressure swing adsorption simulations at room temperature combining adsorption columns with pure silica FAU zeolite and zeolite BRE at a Si/Al ratio of 3. These zeolites have the added advantage of being commercially available.

  14. Method of immobilizing carbon dioxide from gas streams

    DOEpatents

    Holladay, David W.; Haag, Gary L.

    1979-01-01

    This invention is a method for rapidly and continuously immobilizing carbon dioxide contained in various industrial off-gas streams, the carbon dioxide being immobilized as dry, stable, and substantially water-insoluble particulates. Briefly, the method comprises passing the gas stream through a fixed or fluidized bed of hydrated barium hydroxide to remove and immobilize the carbon dioxide by converting the bed to barium carbonate. The method has several important advantages: it can be conducted effectively at ambient temperature; it provides a very rapid reaction rate over a wide range of carbon dioxide concentrations; it provides high decontamination factors; and it has a high capacity for carbon dioxide. The invention is especially well suited for the removal of radioactive carbon dioxide from off-gases generated by nuclear-fuel reprocessing facilities and nuclear power plants.

  15. Electrocatalytic reduction of carbon dioxide on electrodeposited tin-based surfaces

    NASA Astrophysics Data System (ADS)

    Alba, Bianca Christina S.; Camayang, John Carl A.; Mopon, Marlon L.; del Rosario, Julie Anne D.

    2017-08-01

    The electrocatalytic reduction of carbon dioxide to small organic molecular compounds provides a means of generating alternative fuel source while suppressing climate change. Suitable catalysts, however, are necessary to optimize its reaction kinetics towards more valuable products. Consequently, in this study, electrodeposited Sn electrodes have been developed as catalysts for CO2 electroreduction. Deposition potential was varied to produce different Sn catalysts. SEM showed varying morphologies and increasing amount as the applied potential becomes more negative. Cyclic voltammetry and chronoamperometry showed that the activity and stability of the catalysts towards CO2 reduction depend on the morphology and presence of tin oxides. These results provide a better understanding on the performance of electrodeposited Sn-based surfaces as catalysts for CO2 reduction.

  16. The 1992-1993 advanced design program. Part 1: The Mars methane engine project. Part 2: The Mars oxygen processor new furnace

    NASA Astrophysics Data System (ADS)

    Lauer, Stephen; Hoover, Scott; Lawrence, Lori; Paparistodemou, Christos; Taylor, Doug

    1993-04-01

    Three constituents of the Martian atmosphere, methane, carbon dioxide, and oxygen, can be used for internal combustion in engines utilized for future space exploration on Mars. These three gases, considered as the test case in this research, will be examined to determine required flow rates needed for combustion and optimization of engine performance. Results of the test case are examined in relation to a base case of methane and air for comparative purposes. Testing of exhaust temperatures, cylinder pressure, and exhaust gas analysis were performed for the base case and test case. Also described is a study utilizing a zirconia cell to convert carbon dioxide into usable oxygen to help support future Mars missions.

  17. Sinusoidal potential cycling operation of a direct ethanol fuel cell to improving carbon dioxide yields

    NASA Astrophysics Data System (ADS)

    Majidi, Pasha; Pickup, Peter G.

    2014-12-01

    A direct ethanol fuel cell has been operated under sinusoidal (AC) potential cycling conditions in order to increase the yield of carbon dioxide and thereby increase cell efficiency relative to operation at a fixed potential. At 80 °C, faradaic yields of CO2 as high as 25% have been achieved with a PtRu anode catalyst, while the maximum CO2 production at constant potential was 13%. The increased yields under cycling conditions have been attributed to periodic oxidative stripping of adsorbed CO. These results will be important in the optimization of operating conditions for direct ethanol fuel cells, where the benefits of potential cycling are projected to increase as catalysts that produce CO2 more efficiently are implemented.

  18. The 1992-1993 advanced design program. Part 1: The Mars methane engine project. Part 2: The Mars oxygen processor new furnace

    NASA Technical Reports Server (NTRS)

    Lauer, Stephen; Hoover, Scott; Lawrence, Lori; Paparistodemou, Christos; Taylor, Doug

    1993-01-01

    Three constituents of the Martian atmosphere, methane, carbon dioxide, and oxygen, can be used for internal combustion in engines utilized for future space exploration on Mars. These three gases, considered as the test case in this research, will be examined to determine required flow rates needed for combustion and optimization of engine performance. Results of the test case are examined in relation to a base case of methane and air for comparative purposes. Testing of exhaust temperatures, cylinder pressure, and exhaust gas analysis were performed for the base case and test case. Also described is a study utilizing a zirconia cell to convert carbon dioxide into usable oxygen to help support future Mars missions.

  19. Carbon dioxide transport over complex terrain

    USGS Publications Warehouse

    Sun, Jielun; Burns, Sean P.; Delany, A.C.; Oncley, S.P.; Turnipseed, A.; Stephens, B.; Guenther, A.; Anderson, D.E.; Monson, R.

    2004-01-01

    The nocturnal transport of carbon dioxide over complex terrain was investigated. The high carbon dioxide under very stable conditions flows to local low-ground. The regional drainage flow dominates the carbon dioxide transport at the 6 m above the ground and carbon dioxide was transported to the regional low ground. The results show that the local drainage flow was sensitive to turbulent mixing associated with local wind shear.

  20. 46 CFR 147.65 - Carbon dioxide and halon fire extinguishing systems.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 5 2010-10-01 2010-10-01 false Carbon dioxide and halon fire extinguishing systems. 147... dioxide and halon fire extinguishing systems. (a) Carbon dioxide or halon cylinders forming part of a...) Carbon dioxide or halon cylinders must be rejected for further service when they— (1) Leak; (2) Are...

  1. 46 CFR 147.65 - Carbon dioxide and halon fire extinguishing systems.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 5 2014-10-01 2014-10-01 false Carbon dioxide and halon fire extinguishing systems. 147... dioxide and halon fire extinguishing systems. (a) Carbon dioxide or halon cylinders forming part of a...) Carbon dioxide or halon cylinders must be rejected for further service when they— (1) Leak; (2) Are...

  2. Fischer-Tropsch synthesis in supercritical phase carbon dioxide: Recycle rates

    NASA Astrophysics Data System (ADS)

    Soti, Madhav

    With increasing oil prices and attention towards the reduction of anthropogenic CO2, the use of supercritical carbon dioxide for Fischer Tropsch Synthesis (FTS) is showing promise in fulfilling the demand of clean liquid fuels. The evidence of consumption of carbon dioxide means that it need not to be removed from the syngas feed to the Fischer Tropsch reactor after the gasification process. Over the last five years, research at SIUC have shown that FTS in supercritical CO2reduces the selectivities for methane, enhances conversion, reduces the net CO2produces in the coal to liquid fuels process and increase the life of the catalyst. The research has already evaluated the impact of various operating and feed conditions on the FTS for the once through process. We believe that the integration of unreacted feed recycle would enhance conversion, increase the yield and throughput of liquid fuels for the same reactor size. The proposed research aims at evaluating the impact of recycle of the unreacted feed gas along with associated product gases on the performance of supercritical CO2FTS. The previously identified conditions will be utilized and various recycle ratios will be evaluated in this research once the recycle pump and associated fittings have been integrated to the supercritical CO2FTS. In this research two different catalysts (Fe-Zn-K, Fe-Co-Zn-K) were analyzed under SC-FTS in different recycle rate at 350oC and 1200 psi. The use of recycle was found to improve conversion from 80% to close to 100% with both catalysts. The experiment recycle rate at 4.32 and 4.91 was clearly surpassing theoretical recycle curve. The steady state reaction rate constant was increased to 0.65 and 0.8 min-1 for recycle rate of 4.32 and 4.91 respectively. Carbon dioxide selectivity was decreased for both catalyst as it was converting to carbon monoxide. Carbon dioxide consumption was increased from 0.014 to 0.034 mole fraction. This concluded that CO2is being used in the system and converting which created the concentration of the feed gas higher inside the reactor. The research has provided the best conditions for the enhanced conversion while minimizing CO2formation. Though this research was not able to provide the optimal recycle rate it have created the path for the future research to proceed in the right direction. This reduction and utilization of CO2will help to reduce the cost of carbon dioxide removal and saves the environment from carbon dioxide emission.

  3. Carbon Dioxide Insufflation Increases Colonoscopic Adenoma Detection Rate Compared With Air Insufflation.

    PubMed

    Mills, Christopher D; McCamley, Chere; Swan, Michael P

    2018-03-07

    To determine the effect of carbon dioxide insufflation on the most important outcome measure of colonoscopic quality: adenoma detection rate (ADR). Bowel cancer is the second most common cause of cancer deaths in males and females in Australia. Carbon dioxide has in recent times become the insufflation methodology of choice for screening colonoscopy for bowel cancer, as this has been shown to have significant advantages when compared with traditional air insufflation. Endoscopies performed over a period of 9 months immediately before and after the implementation of carbon dioxide insufflation at endoscopy centers were eligible for inclusion. The difference in ADR between the carbon dioxide and air insufflation methods was statistically significant, with an increased ADR in the carbon dioxide group. The superiority of carbon dioxide insufflation was sustained with a logistic regression model, which showed ADR was significantly impacted by insufflation method. Carbon dioxide insufflation is known to reduce abdominal pain, postprocedural duration of abdominal pain, abdominal distension, and analgesic requirements. This study represents for the first time the beneficial effect of carbon dioxide insufflation upon the key quality colonoscopy indicator of ADR.

  4. Carbon dioxide elimination and regeneration of resources in a microwave plasma torch.

    PubMed

    Uhm, Han S; Kwak, Hyoung S; Hong, Yong C

    2016-04-01

    Carbon dioxide gas as a working gas produces a stable plasma-torch by making use of 2.45 GHz microwaves. The temperature of the torch flame is measured by making use of optical spectroscopy and a thermocouple device. Two distinctive regions are exhibited, a bright, whitish region of a high-temperature zone and a bluish, dimmer region of a relatively low-temperature zone. The bright, whitish region is a typical torch based on plasma species where an analytical investigation indicates dissociation of a substantial fraction of carbon dioxide molecules, forming carbon monoxides and oxygen atoms. The emission profiles of the oxygen atoms and the carbon monoxide molecules confirm the theoretical predictions of carbon dioxide disintegration in the torch. Various hydrocarbon materials may be introduced into the carbon dioxide torch, regenerating new resources and reducing carbon dioxide concentration in the torch. As an example, coal powders in the carbon dioxide torch are converted into carbon monoxide according to the reaction of CO2 + C → 2CO, reducing a substantial amount of carbon dioxide concentration in the torch. In this regards, the microwave plasma torch may be one of the best ways of converting the carbon dioxides into useful new materials. Copyright © 2015 Elsevier Ltd. All rights reserved.

  5. Enhancing CO2 electrolysis through synergistic control of non-stoichiometry and doping to tune cathode surface structures

    PubMed Central

    Ye, Lingting; Zhang, Minyi; Huang, Ping; Guo, Guocong; Hong, Maochun; Li, Chunsen; Irvine, John T. S.; Xie, Kui

    2017-01-01

    Sustainable future energy scenarios require significant efficiency improvements in both electricity generation and storage. High-temperature solid oxide cells, and in particular carbon dioxide electrolysers, afford chemical storage of available electricity that can both stabilize and extend the utilization of renewables. Here we present a double doping strategy to facilitate CO2 reduction at perovskite titanate cathode surfaces, promoting adsorption/activation by making use of redox active dopants such as Mn linked to oxygen vacancies and dopants such as Ni that afford metal nanoparticle exsolution. Combined experimental characterization and first-principle calculations reveal that the adsorbed and activated CO2 adopts an intermediate chemical state between a carbon dioxide molecule and a carbonate ion. The dual doping strategy provides optimal performance with no degradation being observed after 100 h of high-temperature operation and 10 redox cycles, suggesting a reliable cathode material for CO2 electrolysis. PMID:28300066

  6. A synthetic pathway for the fixation of carbon dioxide in vitro.

    PubMed

    Schwander, Thomas; Schada von Borzyskowski, Lennart; Burgener, Simon; Cortina, Niña Socorro; Erb, Tobias J

    2016-11-18

    Carbon dioxide (CO 2 ) is an important carbon feedstock for a future green economy. This requires the development of efficient strategies for its conversion into multicarbon compounds. We describe a synthetic cycle for the continuous fixation of CO 2 in vitro. The crotonyl-coenzyme A (CoA)/ethylmalonyl-CoA/hydroxybutyryl-CoA (CETCH) cycle is a reaction network of 17 enzymes that converts CO 2 into organic molecules at a rate of 5 nanomoles of CO 2 per minute per milligram of protein. The CETCH cycle was drafted by metabolic retrosynthesis, established with enzymes originating from nine different organisms of all three domains of life, and optimized in several rounds by enzyme engineering and metabolic proofreading. The CETCH cycle adds a seventh, synthetic alternative to the six naturally evolved CO 2 fixation pathways, thereby opening the way for in vitro and in vivo applications. Copyright © 2016, American Association for the Advancement of Science.

  7. The NOAA Carbon America Program A Focus on Products for Decision- Support

    NASA Astrophysics Data System (ADS)

    Butler, J. H.; Hofmann, D. J.; Tans, P. P.; Peters, W.; Andrews, A. E.; Sweeny, C.; Montzka, S. A.

    2006-12-01

    If society is to manage or reduce carbon emissions in the future, reliable and accurate information on atmospheric carbon dioxide levels for verification of emission reductions will be needed on local, regional, and global scales. The current global carbon dioxide observing network operated by NOAA/ESRL provides a foundation for monitoring and understanding carbon dioxide. For example, atmospheric measurements in Europe suggest that emissions inventories of methane are substantial underestimates. An expanded U.S. Carbon Cycle Atmospheric Observing System is being implemented. Carbon America will consist of approximately 24 aircraft and 12 tall towers obtaining concentrations of carbon gases and other trace species. This observing system needs to be capable of quantitative attribution of all major contributors to the carbon budget of the continent, both manmade and natural. Successful mitigation strategies need independent and credible assessments of their efficacy. Managing carbon emissions will require the involvement of industry, financial markets, and governments at all levels. Without good information, governments will be slow to act, private investments will likely be less than optimal, and financial markets will not develop as they might need to. The atmospheric data and the methods used to derive sources and sinks will be fully open and available in up-to-date form to scientists, the general public, and policymakers. This presentation will provide an overview of NOAA`s role in the North American Carbon Program, our current accomplishments, our plans for the future network, and the currently expected products, services, and information that derive from these and other associated studies. Today's products, while useful, will be eclipsed by those of tomorrow, which will focus heavily on regional emissions expressed on seasonal or shorter time-scales, and will provide needed information for improved predictions in the future.

  8. Discussion of Refrigeration Cycle Using Carbon Dioxide as Refrigerant

    NASA Astrophysics Data System (ADS)

    Ji, Amin; Sun, Miming; Li, Jie; Yin, Gang; Cheng, Keyong; Zhen, Bing; Sun, Ying

    Nowadays, the problem of the environment goes worse, it urges people to research and study new energy-saving and environment-friendly refrigerants, such as carbon dioxide, at present, people do research on carbon dioxide at home and abroad. This paper introduces the property of carbon dioxide as a refrigerant, sums up and analyses carbon dioxide refrigeration cycles, and points out the development and research direction in the future.

  9. Carbon dioxide-soluble polymers and swellable polymers for carbon dioxide applications

    DOEpatents

    DeSimone, Joseph M.; Birnbaum, Eva; Carbonell, Ruben G.; Crette, Stephanie; McClain, James B.; McCleskey, T. Mark; Powell, Kimberly R.; Romack, Timothy J.; Tumas, William

    2004-06-08

    A method for carrying out a catalysis reaction in carbon dioxide comprising contacting a fluid mixture with a catalyst bound to a polymer, the fluid mixture comprising at least one reactant and carbon dioxide, wherein the reactant interacts with the catalyst to form a reaction product. A composition of matter comprises carbon dioxide and a polymer and a reactant present in the carbon dioxide. The polymer has bound thereto a catalyst at a plurality of chains along the length of the polymer, and wherein the reactant interacts with the catalyst to form a reaction product.

  10. Monitoring Exchange of CO2 - A KISS Workshop Report 2009

    NASA Technical Reports Server (NTRS)

    Miller, Charles; Wennberg, Paul

    2009-01-01

    The problem and context: Can top-down estimates of carbon dioxide (CO2) fluxes resolve the anthropogenic emissions of China, India, the United States, and the European Union with an accuracy of +/-10% or better?The workshop "Monitoring Exchange of Carbon Dioxide" was convened at the Keck Institute for Space Studies in Pasadena, California in February 2010 to address this question. The Workshop brought together an international, interdisciplinary group of 24 experts in carbon cycle science, remote sensing, emissions inventory estimation, and inverse modeling. The participants reviewed the potential of space-based and sub-orbital observational and modeling approaches to monitor anthropogenic CO2 emissions in the presence of much larger natural fluxes from the exchange of CO2 between the land, atmosphere, and ocean. This particular challenge was motivated in part by the NRC Report "Verifying Greenhouse Gas Emissions" [Pacala et al., 2010]. This workshop report includes several recommendations for improvements to observing strategies and modeling frameworks for optimal and cost-effective monitoring of carbon exchange

  11. Various supercritical carbon dioxide cycle layouts study for molten carbonate fuel cell application

    NASA Astrophysics Data System (ADS)

    Bae, Seong Jun; Ahn, Yoonhan; Lee, Jekyoung; Lee, Jeong Ik

    2014-12-01

    Various supercritical carbon dioxide (S-CO2) cycles for a power conversion system of a Molten Carbonate Fuel Cell (MCFC) hybrid system are studied in this paper. Re-Compressing Brayton (RCB) cycle, Simple Recuperated Brayton (SRB) cycle and Simple Recuperated Transcritical (SRT) cycle layouts were selected as candidates for this study. In addition, a novel concept of S-CO2 cycle which combines Brayton cycle and Rankine cycle is proposed and intensively studied with other S-CO2 layouts. A parametric study is performed to optimize the total system to be compact and to achieve wider operating range. Performances of each S-CO2 cycle are compared in terms of the thermal efficiency, net electricity of the MCFC hybrid system and approximate total volumes of each S-CO2 cycle. As a result, performance and total physical size of S-CO2 cycle can be better understood for MCFC S-CO2 hybrid system and especially, newly suggested S-CO2 cycle shows some success.

  12. Do fossil plants signal palaeoatmospheric carbon dioxide concentration in the geological past?

    PubMed Central

    McElwain, J. C.

    1998-01-01

    Fossil, subfossil, and herbarium leaves have been shown to provide a morphological signal of the atmospheric carbon dioxide environment in which they developed by means of their stomatal density and index. An inverse relationship between stomatal density/index and atmospheric carbon dioxide concentration has been documented for all the studies to date concerning fossil and subfossil material. Furthermore, this relationship has been demonstrated experimentally by growing plants under elevated and reducedcarbon dioxide concentrations. To date, the mechanism that controls the stomatal density response to atmospheric carbon dioxide concentration remains unknown. However, stomatal parameters of fossil plants have been successfully used as a proxy indicator of palaeo-carbon dioxide levels. This paper presents new estimates of palaeo-atmospheric carbon dioxide concentrations for the Middle Eocene (Lutetian), based on the stomatal ratios of fossil Lauraceae species from Bournemouth in England. Estimates of atmospheric carbon dioxide concentrations derived from stomatal data from plants of the Early Devonian, Late Carboniferous, Early Permian and Middle Jurassic ages are reviewed in the light of new data. Semi-quantitative palaeo-carbon dioxide estimates based on the stomatal ratio (a ratio of the stomatal index of a fossil plant to that of a selected nearest living equivalent) have in the past relied on the use of a Carboniferous standard. The application of a new standard based on the present-day carbon dioxide level is reported here for comparison. The resultant ranges of palaeo-carbon dioxide estimates made from standardized fossil stomatal ratio data are in good agreement with both carbon isotopic data from terrestrial and marine sources and long-term carbon cycle modelling estimates for all the time periods studied. These data indicate elevated atmospheric carbon dioxide concentrations during the Early Devonian, Middle Jurassic and Middle Eocene, and reduced concentrations during the Late Carboniferous and Early Permian. Such data are important in demonstrating the long-term responses of plants to changing carbon dioxide concentrations and in contributing to the database needed for general circulation model climatic analogues.

  13. Technical and economical evaluation of carbon dioxide capture and conversion to methanol process

    NASA Astrophysics Data System (ADS)

    Putra, Aditya Anugerah; Juwari, Handogo, Renanto

    2017-05-01

    Phenomenon of global warming, which is indicated by increasing of earth's surface temperature, is caused by high level of greenhouse gases level in the atmosphere. Carbon dioxide, which increases year by year because of high demand of energy, gives the largest contribution in greenhouse gases. One of the most applied solution to mitigate carbon dioxide level is post-combustion carbon capture technology. Although the technology can absorb up to 90% of carbon dioxide produced, some worries occur that captured carbon dioxide that is stored underground will be released over time. Utilizing captured carbon dioxide could be a promising solution. Captured carbon dioxide can be converted into more valuable material, such as methanol. This research will evaluate the conversion process of captured carbon dioxide to methanol, technically and economically. From the research, it is found that technically methanol can be made from captured carbon dioxide. Product gives 25.6905 kg/s flow with 99.69% purity of methanol. Economical evaluation of the whole conversion process shows that the process is economically feasible. The capture and conversion process needs 176,101,157.69 per year for total annual cost and can be overcome by revenue gained from methanol product sales.

  14. 21 CFR 868.2480 - Cutaneous carbon dioxide (PcCO 2) monitor.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Cutaneous carbon dioxide (PcCO 2) monitor. 868... dioxide (PcCO 2) monitor. (a) Identification. A cutaneous carbon dioxide (PcCO2) monitor is a noninvasive... relative changes in a hemodynamically stable patient's cutaneous carbon dioxide tension as an adjunct to...

  15. 21 CFR 868.2480 - Cutaneous carbon dioxide (PcCO 2) monitor.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Cutaneous carbon dioxide (PcCO 2) monitor. 868... dioxide (PcCO 2) monitor. (a) Identification. A cutaneous carbon dioxide (PcCO2) monitor is a noninvasive... relative changes in a hemodynamically stable patient's cutaneous carbon dioxide tension as an adjunct to...

  16. 40 CFR 60.1230 - What continuous emission monitoring systems must I install for gaseous pollutants?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... systems for oxygen (or carbon dioxide), sulfur dioxide, and carbon monoxide. If you operate a Class I... sulfur dioxide, nitrogen oxides, and oxygen (or carbon dioxide) at the outlet of the air pollution... according to the “Monitoring Requirements” in § 60.13. (c) You must monitor the oxygen (or carbon dioxide...

  17. 40 CFR 60.1230 - What continuous emission monitoring systems must I install for gaseous pollutants?

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... systems for oxygen (or carbon dioxide), sulfur dioxide, and carbon monoxide. If you operate a Class I... sulfur dioxide, nitrogen oxides, and oxygen (or carbon dioxide) at the outlet of the air pollution... according to the “Monitoring Requirements” in § 60.13. (c) You must monitor the oxygen (or carbon dioxide...

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

    PubMed

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

    2015-12-17

    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.

  19. Carbon Dioxide Removal via Passive Thermal Approaches

    NASA Technical Reports Server (NTRS)

    Lawson, Michael; Hanford, Anthony; Conger, Bruce; Anderson, Molly

    2011-01-01

    A paper describes a regenerable approach to separate carbon dioxide from other cabin gases by means of cooling until the carbon dioxide forms carbon dioxide ice on the walls of the physical device. Currently, NASA space vehicles remove carbon dioxide by reaction with lithium hydroxide (LiOH) or by adsorption to an amine, a zeolite, or other sorbent. Use of lithium hydroxide, though reliable and well-understood, requires significant mass for all but the shortest missions in the form of lithium hydroxide pellets, because the reaction of carbon dioxide with lithium hydroxide is essentially irreversible. This approach is regenerable, uses less power than other historical approaches, and it is almost entirely passive, so it is more economical to operate and potentially maintenance- free for long-duration missions. In carbon dioxide removal mode, this approach passes a bone-dry stream of crew cabin atmospheric gas through a metal channel in thermal contact with a radiator. The radiator is pointed to reject thermal loads only to space. Within the channel, the working stream is cooled to the sublimation temperature of carbon dioxide at the prevailing cabin pressure, leading to formation of carbon dioxide ice on the channel walls. After a prescribed time or accumulation of carbon dioxide ice, for regeneration of the device, the channel is closed off from the crew cabin and the carbon dioxide ice is sublimed and either vented to the environment or accumulated for recovery of oxygen in a fully regenerative life support system.

  20. Triple-Pulse Integrated Path Differential Absorption Lidar for Carbon Dioxide Measurement - Novel Lidar Technologies and Techniques with Path to Space

    NASA Technical Reports Server (NTRS)

    Singh, Upendra N.; Refaat, Tamer F.; Petros, Mulugeta

    2017-01-01

    The societal benefits of understanding climate change through identification of global carbon dioxide sources and sinks led to the desired NASA's active sensing of carbon dioxide emissions over nights, days, and seasons (ASCENDS) space-based missions of global carbon dioxide measurements. For more than 15 years, NASA Langley Research Center (LaRC) have developed several carbon dioxide active remote sensors using the differential absorption lidar (DIAL) technique operating at the two-micron wavelength. Currently, an airborne two-micron triple-pulse integrated path differential absorption (IPDA) lidar is under development. This IPDA lidar measures carbon dioxide as well as water vapor, the dominant interfering molecule on carbon dioxide remote sensing. Advancement of this triple-pulse IPDA lidar development is presented.

  1. Carbon dioxide sequestration using NaHSO4 and NaOH: A dissolution and carbonation optimisation study.

    PubMed

    Sanna, Aimaro; Steel, Luc; Maroto-Valer, M Mercedes

    2017-03-15

    The use of NaHSO 4 to leach out Mg fromlizardite-rich serpentinite (in form of MgSO 4 ) and the carbonation of CO 2 (captured in form of Na 2 CO 3 using NaOH) to form MgCO 3 and Na 2 SO 4 was investigated. Unlike ammonium sulphate, sodium sulphate can be separated via precipitation during the recycling step avoiding energy intensive evaporation process required in NH 4 -based processes. To determine the effectiveness of the NaHSO 4 /NaOH process when applied to lizardite, the optimisation of the dissolution and carbonation steps were performed using a UK lizardite-rich serpentine. Temperature, solid/liquid ratio, particle size, concentration and molar ratio were evaluated. An optimal dissolution efficiency of 69.6% was achieved over 3 h at 100 °C using 1.4 M sodium bisulphate and 50 g/l serpentine with particle size 75-150 μm. An optimal carbonation efficiency of 95.4% was achieved over 30 min at 90 °C and 1:1 magnesium:sodium carbonate molar ratio using non-synthesised solution. The CO 2 sequestration capacity was 223.6 g carbon dioxide/kg serpentine (66.4% in terms of Mg bonded to hydromagnesite), which is comparable with those obtained using ammonium based processes. Therefore, lizardite-rich serpentinites represent a valuable resource for the NaHSO 4 /NaOH based pH swing mineralisation process. Copyright © 2016 Elsevier Ltd. All rights reserved.

  2. Active Control of pH in the Bioculture System Through Carbon Dioxide Control

    NASA Technical Reports Server (NTRS)

    Monhollon, Luke; Pletcher, David; Hauss, Jessica

    2016-01-01

    For successful cell research, the growth culture environment must be tightly controlled. Deviance from the optimal conditions will mask the desired variable being analyzed or lead to inconstancies in the results. In standard laboratories, technology and procedures are readily available for the reliable control of variables such as temperature, pH, nutrient loading, and dissolved gases. Due to the nature of spaceflight, and the inherent constraints to engineering designs, these same elements become a challenge to maintain at stable values by both automated and manual approaches. Launch mass, volume, and power usage create significant constraints to cell culture systems; nonetheless, innovative solutions for active environmental controls are available. The acidity of the growth media cannot be measured through standard probes due to the degradation of electrodes and reliance on indicators for chromatography. Alternatively, carbon dioxide sensors are capable of monitoring the pH by leveraging the relationship between the partial pressure of carbon dioxide and carbonic acid in solution across a membrane. In microgravity cell growth systems, the gas delivery system can be used to actively maintain the media at the proper acidity by maintaining a suitable gas mixture around permeable tubing. Through this method, launch mass and volume are significantly reduced through the efficient use of the limited gas supply in orbit.

  3. Capacitance‐Assisted Sustainable Electrochemical Carbon Dioxide Mineralisation

    PubMed Central

    Lamb, Katie J.; Dowsett, Mark R.; Chatzipanagis, Konstantinos; Scullion, Zhan Wei; Kröger, Roland; Lee, James D.

    2017-01-01

    Abstract An electrochemical cell comprising a novel dual‐component graphite and Earth‐crust abundant metal anode, a hydrogen producing cathode and an aqueous sodium chloride electrolyte was constructed and used for carbon dioxide mineralisation. Under an atmosphere of 5 % carbon dioxide in nitrogen, the cell exhibited both capacitive and oxidative electrochemistry at the anode. The graphite acted as a supercapacitive reagent concentrator, pumping carbon dioxide into aqueous solution as hydrogen carbonate. Simultaneous oxidation of the anodic metal generated cations, which reacted with the hydrogen carbonate to give mineralised carbon dioxide. Whilst conventional electrochemical carbon dioxide reduction requires hydrogen, this cell generates hydrogen at the cathode. Carbon capture can be achieved in a highly sustainable manner using scrap metal within the anode, seawater as the electrolyte, an industrially relevant gas stream and a solar panel as an effective zero‐carbon energy source. PMID:29171724

  4. Technique for Simultaneous Determination of [35S]Sulfide and [14C]Carbon Dioxide in Anaerobic Aqueous Samples †

    PubMed Central

    Taylor, Craig D.; Ljungdahl, Per O.; Molongoski, John J.

    1981-01-01

    A technique for the simultaneous determination of [35S]sulfide and [14C]carbon dioxide produced in anaerobic aqueous samples dual-labeled with [35S]sulfate and a 14C-organic substrate is described. The method involves the passive distillation of sulfide and carbon dioxide from an acidified water sample and their subsequent separation by selective chemical absorption. The recovery of sulfide was 93% for amounts ranging from 0.35 to 50 μmol; recovery of carbon dioxide was 99% in amounts up to 20 μmol. Within these delineated ranges of total sulfide and carbon dioxide, 1 nmol of [35S]sulfide and 7.5 nmol of [14C]carbon dioxide were separated and quantified. Correction factors were formulated for low levels of radioisotopic cross-contamination by sulfide, carbon dioxide, and volatile organic acids. The overall standard error of the method was ±4% for sulfide and ±6% for carbon dioxide. PMID:16345742

  5. Natural deep eutectic solvents (NADES) as green solvents for carbon dioxide capture

    NASA Astrophysics Data System (ADS)

    Mulia, Kamarza; Putri, Sylvania; Krisanti, Elsa; Nasruddin

    2017-03-01

    This study was conducted to determine the effectiveness of Natural Deep Eutectic Solvent (NADES), consisting of choline chloride and a hydrogen bonding donor (HBD) compound, in terms of carbon dioxide absorption. Solubility of carbon dioxide in NADES was found to be influenced HBD compound used and choline chloride to HBD ratio, carbon dioxide pressure, and contact time. HBD and choline/HBD ratios used were 1,2-propanediol (1:2), glycerol (1:2), and malic acid (1:1). The carbon dioxide absorption measurement was conducted using an apparatus that utilizes the volumetric method. Absorption curves were obtained up to pressures of 30 bar, showing a linear relationship between the amount absorbed and the final pressure of carbon dioxide. The choline and 1,2-propanediol eutectic mixture absorbs the highest amount of carbon dioxide, approaching 0.1 mole-fraction at 3.0 MPa and 50°C. We found that NADES ability to absorb carbon dioxide correlates with its polarity as tested using Nile Red as a solvatochromic probe.

  6. A metal-free electrocatalyst for carbon dioxide reduction to multi-carbon hydrocarbons and oxygenates

    NASA Astrophysics Data System (ADS)

    Wu, Jingjie; Ma, Sichao; Sun, Jing; Gold, Jake I.; Tiwary, Chandrasekhar; Kim, Byoungsu; Zhu, Lingyang; Chopra, Nitin; Odeh, Ihab N.; Vajtai, Robert; Yu, Aaron Z.; Luo, Raymond; Lou, Jun; Ding, Guqiao; Kenis, Paul J. A.; Ajayan, Pulickel M.

    2016-12-01

    Electroreduction of carbon dioxide into higher-energy liquid fuels and chemicals is a promising but challenging renewable energy conversion technology. Among the electrocatalysts screened so far for carbon dioxide reduction, which includes metals, alloys, organometallics, layered materials and carbon nanostructures, only copper exhibits selectivity towards formation of hydrocarbons and multi-carbon oxygenates at fairly high efficiencies, whereas most others favour production of carbon monoxide or formate. Here we report that nanometre-size N-doped graphene quantum dots (NGQDs) catalyse the electrochemical reduction of carbon dioxide into multi-carbon hydrocarbons and oxygenates at high Faradaic efficiencies, high current densities and low overpotentials. The NGQDs show a high total Faradaic efficiency of carbon dioxide reduction of up to 90%, with selectivity for ethylene and ethanol conversions reaching 45%. The C2 and C3 product distribution and production rate for NGQD-catalysed carbon dioxide reduction is comparable to those obtained with copper nanoparticle-based electrocatalysts.

  7. Effects of fuel and forest conservation on future levels of atmospheric carbon dioxide.

    PubMed

    Walker, J C; Kasting, J F

    1992-01-01

    We develop a numerical simulation of the global biogeochemical cycles of carbon that works over time scales extending from years to millions of years. The ocean is represented by warm and cold shallow water reservoirs, a thermocline reservoir, and deep Atlantic, Indian, and Pacific reservoirs. The atmosphere is characterized by a single carbon reservoir and the global biota by a single biomass reservoir. The simulation includes the rock cycle, distinguishing between shelf carbonate and pelagic carbonate precipitation, with distinct lysocline depths in the three deep ocean reservoirs. Dissolution of pelagic carbonates in response to decrease in lysocline depth is included. The simulation is tuned to reproduce the observed radiocarbon record resulting from atomic weapon testing. It is tuned also to reproduce the distribution of dissolved phosphate and total dissolved carbon between the ocean reservoirs as well as the carbon isotope ratios for both 13C and 14C in ocean and atmosphere. The simulation reproduces reasonably well the historical record of carbon dioxide partial pressure as well as the atmospheric isotope ratios for 13C and 14C over the last 200 yr as these have changed in response to fossil fuel burning and land use changes, principally forest clearance. The agreements between observation and calculation involves the assumption of a carbon dioxide fertilization effect in which the rate of production of biomass increases with increasing carbon dioxide partial pressure. At present the fertilization effect of increased carbon dioxide outweighs the effects of forest clearance, so the biota comprises an overall sink of atmospheric carbon dioxide sufficiently large to bring the budget approximately into balance. This simulation is used to examine the future evolution of carbon dioxide and its sensitivity to assumptions about the rate of fossil fuel burning and of forest clearance. Over times extending up to thousands of years, the results are insensitive to the formulation of the rock cycle and to the dissolution of deep sea carbonate sediments. Atmospheric carbon dioxide continues to increase as long fossil fuel is burned at a significant rate, because the rate of fossil fuel production of carbon dioxide far exceeds the rates at which geochemical processes can remove carbon dioxide from the atmosphere. The maximum concentration of carbon dioxide achieved in the atmosphere depends on the total amount of fossil fuel burned, but only weakly on the rate of burning. The future course of atmospheric carbon dioxide is, however, very sensitive to the fate of the forests in this simulation because of the important role assigned to carbon dioxide fertilization of plant growth rate. Forest clearance drives up atmospheric carbon dioxide not only by converting biomass into atmospheric carbon dioxide but more importantly by reducing the capacity of the biota to sequester fossil fuel carbon dioxide. In this simulation, atmospheric carbon dioxide levels could be sustained indefinitely below 500 parts per million (ppm) if fossil fuel combustion rates were immediately cut from their present value of 5 x 10(14) m/y to 0.2 x 10(14) m/y (a factor of 25 reduction) and if further forest clearance were halted. If neither of these conditions is met and if we consume most of the world's fossil fuel reserves, peak carbon dioxide concentrations of 1000-2000 ppm are probable within the next few centuries.

  8. Nitrous oxide as a humane method for piglet euthanasia: behavior and electroencephalography

    USDA-ARS?s Scientific Manuscript database

    The search for humane methods to euthanize piglets is critical to address public concern that current methods are not optimal. Blunt force trauma is considered humane but aesthetically objectionable. Carbon dioxide (CO2) is used but criticized as aversive. This research sought to: 1) evaluate the av...

  9. 21 CFR 184.1240 - Carbon dioxide.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 3 2013-04-01 2013-04-01 false Carbon dioxide. 184.1240 Section 184.1240 Food and... Substances Affirmed as GRAS § 184.1240 Carbon dioxide. (a) Carbon dioxide (empirical formula CO2, CAS Reg. No.... The solid form, dry ice, sublimes under atmospheric pressure at a temperature of −78.5 °C. Carbon...

  10. 21 CFR 184.1240 - Carbon dioxide.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 3 2012-04-01 2012-04-01 false Carbon dioxide. 184.1240 Section 184.1240 Food and... Substances Affirmed as GRAS § 184.1240 Carbon dioxide. (a) Carbon dioxide (empirical formula CO2, CAS Reg. No.... The solid form, dry ice, sublimes under atmospheric pressure at a temperature of −78.5 °C. Carbon...

  11. 21 CFR 184.1240 - Carbon dioxide.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 3 2011-04-01 2011-04-01 false Carbon dioxide. 184.1240 Section 184.1240 Food and... Substances Affirmed as GRAS § 184.1240 Carbon dioxide. (a) Carbon dioxide (empirical formula CO2, CAS Reg. No.... The solid form, dry ice, sublimes under atmospheric pressure at a temperature of −78.5 °C. Carbon...

  12. 21 CFR 868.5300 - Carbon dioxide absorbent.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Carbon dioxide absorbent. 868.5300 Section 868...) MEDICAL DEVICES ANESTHESIOLOGY DEVICES Therapeutic Devices § 868.5300 Carbon dioxide absorbent. (a) Identification. A carbon dioxide absorbent is a device intended for medical purposes that consists of an...

  13. 21 CFR 868.5300 - Carbon dioxide absorbent.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Carbon dioxide absorbent. 868.5300 Section 868...) MEDICAL DEVICES ANESTHESIOLOGY DEVICES Therapeutic Devices § 868.5300 Carbon dioxide absorbent. (a) Identification. A carbon dioxide absorbent is a device intended for medical purposes that consists of an...

  14. 21 CFR 868.5300 - Carbon dioxide absorbent.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Carbon dioxide absorbent. 868.5300 Section 868...) MEDICAL DEVICES ANESTHESIOLOGY DEVICES Therapeutic Devices § 868.5300 Carbon dioxide absorbent. (a) Identification. A carbon dioxide absorbent is a device intended for medical purposes that consists of an...

  15. 46 CFR 193.15-20 - Carbon dioxide storage.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 7 2011-10-01 2011-10-01 false Carbon dioxide storage. 193.15-20 Section 193.15-20 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS FIRE PROTECTION EQUIPMENT Carbon Dioxide Extinguishing Systems, Details § 193.15-20 Carbon dioxide storage. (a...

  16. 46 CFR 193.15-20 - Carbon dioxide storage.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 7 2010-10-01 2010-10-01 false Carbon dioxide storage. 193.15-20 Section 193.15-20 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS FIRE PROTECTION EQUIPMENT Carbon Dioxide Extinguishing Systems, Details § 193.15-20 Carbon dioxide storage. (a...

  17. U.S. Energy-Related Carbon Dioxide Emissions

    EIA Publications

    2017-01-01

    U.S. Energy Information Administration releases its online analysis of 2016 energy-related carbon dioxide emissions today. It indicates U.S. carbon dioxide emissions from the consumption of fossil fuels were 5,170 million metric tons carbon dioxide in 2016, a decrease of 1.7 percent from the 2015 level. Energy-related carbon dioxide emissions have declined in six of the last ten years. This analysis is based on data contained in the August 2017 Monthly Energy Review.

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

    PubMed Central

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

    2015-01-01

    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. PMID:26674957

  19. Swarm intelligence for multi-objective optimization of synthesis gas production

    NASA Astrophysics Data System (ADS)

    Ganesan, T.; Vasant, P.; Elamvazuthi, I.; Ku Shaari, Ku Zilati

    2012-11-01

    In the chemical industry, the production of methanol, ammonia, hydrogen and higher hydrocarbons require synthesis gas (or syn gas). The main three syn gas production methods are carbon dioxide reforming (CRM), steam reforming (SRM) and partial-oxidation of methane (POM). In this work, multi-objective (MO) optimization of the combined CRM and POM was carried out. The empirical model and the MO problem formulation for this combined process were obtained from previous works. The central objectives considered in this problem are methane conversion, carbon monoxide selectivity and the hydrogen to carbon monoxide ratio. The MO nature of the problem was tackled using the Normal Boundary Intersection (NBI) method. Two techniques (Gravitational Search Algorithm (GSA) and Particle Swarm Optimization (PSO)) were then applied in conjunction with the NBI method. The performance of the two algorithms and the quality of the solutions were gauged by using two performance metrics. Comparative studies and results analysis were then carried out on the optimization results.

  20. New study on the correlation between carbon dioxide concentration in the environment and radon monitor devices.

    PubMed

    Shahrokhi, A; Burghele, B D; Fábián, F; Kovács, T

    2015-12-01

    The influence of high geogenic carbon dioxide concentrations on monitoring devices might present a significant challenge to the measurement of radon concentrations in environments with a high level of carbon dioxide concentration such as volcano sites, mofettes, caves, etc. In this study, the influence of carbon dioxide concentration on several different types of radon monitor devices - including Alpha Spectrometry (Sarad RTM 2200, EQF 3220, RAD7), Ionizing Chamber (AlphaGUARD PQ2000 PRO) and Active Cell (Active scintillation cell, Pylon 300A) - was examined to represent new aspects of radon measuring in environments with carbon dioxide. In light of the results, all measuring devices were exposed to variable conditions affected by carbon dioxide concentration, except for the AlphaGUARD, which was kept in a steady state throughout the experiment. It was observed that alpha spectroscopy devices were affected by carbon dioxide, since measured radon concentrations decreased in the presence of 70% and 90% carbon dioxide concentrations by 26.5 ± 2% and 14.5 ± 2.5% for EQF 3220, and 32 ± 2% and 35.5 ± 2% for RTM 2200. However, the ionizing chamber instrument was unaffected by changes in carbon dioxide concentration. It was determined that the RAD7 performed relatively inefficiently in the presence of carbon dioxide concentrations higher than 67% by an overall efficiency factor of approximately 0.52, confirming that it is not an admissible radon monitor instrument in environments with high carbon dioxide concentrations. Copyright © 2015 Elsevier Ltd. All rights reserved.

  1. Utilizing Diffusion Theory to predict carbon dioxide concentration in an indoor environment

    NASA Astrophysics Data System (ADS)

    Kramer, Andrew R.

    This research details a new method of relating sources of carbon dioxide to carbon dioxide concentration in a room operating in a reduced ventilation mode by utilizing Diffusion Theory. The theoretical basis of this research involved solving Fick's Second Law of Diffusion in spherical coordinates for a source of carbon dioxide flowing at a constant rate and located in the center of an impermeable spherical boundary. The solution was developed using a Laplace Transformation. A spherical diffusion test chamber was constructed and used to validate and benchmark the developed theory. The method was benchmarked by using Dispersion Coefficients for large carbon dioxide flow rates due to diffusion induced convection. The theoretical model was adapted to model a room operating with restricted ventilation in the presence of a known, constant source of carbon dioxide. The room was modeled as a sphere of volume equal to the room and utilized a Dispersion Coefficient that is consistent with published values. The developed Diffusion Model successfully predicted the spatial concentration of carbon dioxide in a room operating in a reduced ventilation mode in the presence of a source of carbon dioxide. The flow rates of carbon dioxide that were used in the room are comparable to the average flow rate of carbon dioxide from a person during quiet breathing, also known as the Tidal Breathing. This indicates the Diffusion Model developed from this research has the potential to correlate carbon dioxide concentration with static occupancy levels which can lead to energy savings through a reduction in air exchange rates when low occupancy is detected.

  2. Alkali metal carbon dioxide electrochemical system for energy storage and/or conversion of carbon dioxide to oxygen

    NASA Technical Reports Server (NTRS)

    Hagedorn, Norman H. (Inventor)

    1993-01-01

    An alkali metal, such as lithium, is the anodic reactant; carbon dioxide or a mixture of carbon dioxide and carbon monoxide is the cathodic reactant; and carbonate of the alkali metal is the electrolyte in an electrochemical cell for the storage and delivery of electrical energy. Additionally, alkali metal-carbon dioxide battery systems include a plurality of such electrochemical cells. Gold is a preferred catalyst for reducing the carbon dioxide at the cathode. The fuel cell of the invention produces electrochemical energy through the use of an anodic reactant which is extremely energetic and light, and a cathodic reactant which can be extracted from its environment and therefore exacts no transportation penalty. The invention is, therefore, especially useful in extraterrestrial environments.

  3. Capacitance-Assisted Sustainable Electrochemical Carbon Dioxide Mineralisation.

    PubMed

    Lamb, Katie J; Dowsett, Mark R; Chatzipanagis, Konstantinos; Scullion, Zhan Wei; Kröger, Roland; Lee, James D; Aguiar, Pedro M; North, Michael; Parkin, Alison

    2018-01-10

    An electrochemical cell comprising a novel dual-component graphite and Earth-crust abundant metal anode, a hydrogen producing cathode and an aqueous sodium chloride electrolyte was constructed and used for carbon dioxide mineralisation. Under an atmosphere of 5 % carbon dioxide in nitrogen, the cell exhibited both capacitive and oxidative electrochemistry at the anode. The graphite acted as a supercapacitive reagent concentrator, pumping carbon dioxide into aqueous solution as hydrogen carbonate. Simultaneous oxidation of the anodic metal generated cations, which reacted with the hydrogen carbonate to give mineralised carbon dioxide. Whilst conventional electrochemical carbon dioxide reduction requires hydrogen, this cell generates hydrogen at the cathode. Carbon capture can be achieved in a highly sustainable manner using scrap metal within the anode, seawater as the electrolyte, an industrially relevant gas stream and a solar panel as an effective zero-carbon energy source. © 2017 The Authors. Published by Wiley-VCH Verlag GmbH & Co. KGaA.

  4. Carbon Dioxide Emission Peak and Green Innovation-Driven — Research of Escaping Middle Income Trap for China

    NASA Astrophysics Data System (ADS)

    Liu, Jianya; Sun, Zhenqing; Lan, Zirui; Kou, Chunxiao

    2018-06-01

    This study explains and demonstrates whether China has the capability to avoid the Middle Income Trap. The 19th National Congress of CPC report points out: by 2035, China will become an international leader in innovation. At present, China is in the juncture of changing the mode of development, optimizing the economic structure and transforming the growth momentum. The juncture means that it is possible to be stagnation or retrogression of national economy as the national ability of innovation is insufficient, then sticking in the middle-income trap (MIC) for a long time. In this paper, we used the TFP to prove that the input-output ratio of different regions of China, with the per capita GDP and carbon emissions are fitting again, dividing China into optimized zones and non-optimized zones. It can be seen from the results that the optimized zones have achieved the peak of carbon emission and had relative advantages in green innovation. However, if China wants to achieve her overall carbon emissions and get out of the middle income trap, she must optimize the development zones to spillover technologies and talents.

  5. 21 CFR 582.1240 - Carbon dioxide.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Carbon dioxide. 582.1240 Section 582.1240 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS....1240 Carbon dioxide. (a) Product. Carbon dioxide. (b) Conditions of use. This substance is generally...

  6. 40 CFR 86.124-78 - Carbon dioxide analyzer calibration.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 18 2010-07-01 2010-07-01 false Carbon dioxide analyzer calibration... Complete Heavy-Duty Vehicles; Test Procedures § 86.124-78 Carbon dioxide analyzer calibration. Prior to its introduction into service and monthly thereafter the NDIR carbon dioxide analyzer shall be calibrated: (a...

  7. 40 CFR 86.524-78 - Carbon dioxide analyzer calibration.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 18 2010-07-01 2010-07-01 false Carbon dioxide analyzer calibration... Regulations for 1978 and Later New Motorcycles; Test Procedures § 86.524-78 Carbon dioxide analyzer calibration. (a) Prior to its introduction into service and monthly thereafter the NDIR carbon dioxide...

  8. 21 CFR 884.1300 - Uterotubal carbon dioxide insufflator and accessories.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Uterotubal carbon dioxide insufflator and... Gynecological Diagnostic Devices § 884.1300 Uterotubal carbon dioxide insufflator and accessories. (a) Identification. A uterotubal carbon dioxide insufflator and accessories is a device used to test the patency...

  9. 27 CFR 24.319 - Carbon dioxide record.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2010-04-01 2010-04-01 false Carbon dioxide record. 24..., DEPARTMENT OF THE TREASURY LIQUORS WINE Records and Reports § 24.319 Carbon dioxide record. A proprietor who uses carbon dioxide in still wine shall maintain a record of the laboratory tests conducted to...

  10. 46 CFR 95.15-60 - Odorizing units.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... EQUIPMENT Carbon Dioxide Extinguishing Systems, Details § 95.15-60 Odorizing units. Each carbon dioxide... the scent of wintergreen, the detection of which will serve as an indication that carbon dioxide gas is present in a protected area and any other area into which the carbon dioxide may migrate. “Altered...

  11. 21 CFR 582.1240 - Carbon dioxide.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 6 2012-04-01 2012-04-01 false Carbon dioxide. 582.1240 Section 582.1240 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS....1240 Carbon dioxide. (a) Product. Carbon dioxide. (b) Conditions of use. This substance is generally...

  12. 21 CFR 582.1240 - Carbon dioxide.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 6 2013-04-01 2013-04-01 false Carbon dioxide. 582.1240 Section 582.1240 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS....1240 Carbon dioxide. (a) Product. Carbon dioxide. (b) Conditions of use. This substance is generally...

  13. 46 CFR 76.15-60 - Odorizing units.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... Carbon Dioxide Extinguishing Systems, Details § 76.15-60 Odorizing units. Each carbon dioxide... the scent of wintergreen, the detection of which will serve as an indication that carbon dioxide gas is present in a protected area and any other area into which the carbon dioxide may migrate. “Altered...

  14. 27 CFR 24.319 - Carbon dioxide record.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2014-04-01 2014-04-01 false Carbon dioxide record. 24..., DEPARTMENT OF THE TREASURY ALCOHOL WINE Records and Reports § 24.319 Carbon dioxide record. A proprietor who uses carbon dioxide in still wine shall maintain a record of the laboratory tests conducted to...

  15. 27 CFR 24.319 - Carbon dioxide record.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2013-04-01 2013-04-01 false Carbon dioxide record. 24..., DEPARTMENT OF THE TREASURY ALCOHOL WINE Records and Reports § 24.319 Carbon dioxide record. A proprietor who uses carbon dioxide in still wine shall maintain a record of the laboratory tests conducted to...

  16. 27 CFR 24.319 - Carbon dioxide record.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2012-04-01 2012-04-01 false Carbon dioxide record. 24..., DEPARTMENT OF THE TREASURY LIQUORS WINE Records and Reports § 24.319 Carbon dioxide record. A proprietor who uses carbon dioxide in still wine shall maintain a record of the laboratory tests conducted to...

  17. 46 CFR 193.15-17 - Odorizing units.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... EQUIPMENT Carbon Dioxide and Clean Agent Extinguishing Systems, Details § 193.15-17 Odorizing units. Each carbon dioxide extinguishing system installed or altered after July 9, 2013, must have an approved... carbon dioxide gas is present in a protected area and any other area into which the carbon dioxide may...

  18. 40 CFR 86.124-78 - Carbon dioxide analyzer calibration.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 19 2014-07-01 2014-07-01 false Carbon dioxide analyzer calibration... Complete Heavy-Duty Vehicles; Test Procedures § 86.124-78 Carbon dioxide analyzer calibration. Prior to its introduction into service and monthly thereafter the NDIR carbon dioxide analyzer shall be calibrated: (a...

  19. 46 CFR 193.15-17 - Odorizing units.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... EQUIPMENT Carbon Dioxide and Clean Agent Extinguishing Systems, Details § 193.15-17 Odorizing units. Each carbon dioxide extinguishing system installed or altered after July 9, 2013, must have an approved... carbon dioxide gas is present in a protected area and any other area into which the carbon dioxide may...

  20. 46 CFR 76.15-60 - Odorizing units.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... Carbon Dioxide Extinguishing Systems, Details § 76.15-60 Odorizing units. Each carbon dioxide... the scent of wintergreen, the detection of which will serve as an indication that carbon dioxide gas is present in a protected area and any other area into which the carbon dioxide may migrate. “Altered...

  1. 21 CFR 582.1240 - Carbon dioxide.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 6 2014-04-01 2014-04-01 false Carbon dioxide. 582.1240 Section 582.1240 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS....1240 Carbon dioxide. (a) Product. Carbon dioxide. (b) Conditions of use. This substance is generally...

  2. 21 CFR 884.1300 - Uterotubal carbon dioxide insufflator and accessories.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Uterotubal carbon dioxide insufflator and... Gynecological Diagnostic Devices § 884.1300 Uterotubal carbon dioxide insufflator and accessories. (a) Identification. A uterotubal carbon dioxide insufflator and accessories is a device used to test the patency...

  3. 46 CFR 76.15-60 - Odorizing units.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... Carbon Dioxide Extinguishing Systems, Details § 76.15-60 Odorizing units. Each carbon dioxide... the scent of wintergreen, the detection of which will serve as an indication that carbon dioxide gas is present in a protected area and any other area into which the carbon dioxide may migrate. “Altered...

  4. 40 CFR 86.124-78 - Carbon dioxide analyzer calibration.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 19 2012-07-01 2012-07-01 false Carbon dioxide analyzer calibration... Complete Heavy-Duty Vehicles; Test Procedures § 86.124-78 Carbon dioxide analyzer calibration. Prior to its introduction into service and monthly thereafter the NDIR carbon dioxide analyzer shall be calibrated: (a...

  5. 21 CFR 884.1300 - Uterotubal carbon dioxide insufflator and accessories.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Uterotubal carbon dioxide insufflator and... Gynecological Diagnostic Devices § 884.1300 Uterotubal carbon dioxide insufflator and accessories. (a) Identification. A uterotubal carbon dioxide insufflator and accessories is a device used to test the patency...

  6. 27 CFR 24.319 - Carbon dioxide record.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ..., DEPARTMENT OF THE TREASURY LIQUORS WINE Records and Reports § 24.319 Carbon dioxide record. A proprietor who uses carbon dioxide in still wine shall maintain a record of the laboratory tests conducted to... 27 Alcohol, Tobacco Products and Firearms 1 2011-04-01 2011-04-01 false Carbon dioxide record. 24...

  7. 21 CFR 582.1240 - Carbon dioxide.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ....1240 Carbon dioxide. (a) Product. Carbon dioxide. (b) Conditions of use. This substance is generally... 21 Food and Drugs 6 2011-04-01 2011-04-01 false Carbon dioxide. 582.1240 Section 582.1240 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS...

  8. 46 CFR 76.15-20 - Carbon dioxide storage.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 3 2013-10-01 2013-10-01 false Carbon dioxide storage. 76.15-20 Section 76.15-20 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) PASSENGER VESSELS FIRE PROTECTION EQUIPMENT Carbon Dioxide Extinguishing Systems, Details § 76.15-20 Carbon dioxide storage. (a) Except as...

  9. 46 CFR 95.15-20 - Carbon dioxide storage.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 4 2010-10-01 2010-10-01 false Carbon dioxide storage. 95.15-20 Section 95.15-20 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) CARGO AND MISCELLANEOUS VESSELS FIRE PROTECTION EQUIPMENT Carbon Dioxide Extinguishing Systems, Details § 95.15-20 Carbon dioxide storage. (a...

  10. 46 CFR 76.15-20 - Carbon dioxide storage.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 3 2011-10-01 2011-10-01 false Carbon dioxide storage. 76.15-20 Section 76.15-20 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) PASSENGER VESSELS FIRE PROTECTION EQUIPMENT Carbon Dioxide Extinguishing Systems, Details § 76.15-20 Carbon dioxide storage. (a) Except as...

  11. 46 CFR 95.15-20 - Carbon dioxide storage.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 4 2012-10-01 2012-10-01 false Carbon dioxide storage. 95.15-20 Section 95.15-20 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) CARGO AND MISCELLANEOUS VESSELS FIRE PROTECTION EQUIPMENT Carbon Dioxide Extinguishing Systems, Details § 95.15-20 Carbon dioxide storage. (a...

  12. 46 CFR 76.15-20 - Carbon dioxide storage.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 3 2012-10-01 2012-10-01 false Carbon dioxide storage. 76.15-20 Section 76.15-20 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) PASSENGER VESSELS FIRE PROTECTION EQUIPMENT Carbon Dioxide Extinguishing Systems, Details § 76.15-20 Carbon dioxide storage. (a) Except as...

  13. 46 CFR 95.15-20 - Carbon dioxide storage.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 4 2011-10-01 2011-10-01 false Carbon dioxide storage. 95.15-20 Section 95.15-20 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) CARGO AND MISCELLANEOUS VESSELS FIRE PROTECTION EQUIPMENT Carbon Dioxide Extinguishing Systems, Details § 95.15-20 Carbon dioxide storage. (a...

  14. 46 CFR 76.15-20 - Carbon dioxide storage.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 3 2014-10-01 2014-10-01 false Carbon dioxide storage. 76.15-20 Section 76.15-20 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) PASSENGER VESSELS FIRE PROTECTION EQUIPMENT Carbon Dioxide Extinguishing Systems, Details § 76.15-20 Carbon dioxide storage. (a) Except as...

  15. Bioelectrochemical conversion of CO2 to value added product formate using engineered Methylobacterium extorquens.

    PubMed

    Jang, Jungho; Jeon, Byoung Wook; Kim, Yong Hwan

    2018-05-08

    The conversion of carbon dioxide to formate is a fundamental step for building C1 chemical platforms. Methylobacterium extorquens AM1 was reported to show remarkable activity converting carbon dioxide into formate. Formate dehydrogenase 1 from M. extorquens AM1 (MeFDH1) was verified as the key responsible enzyme for the conversion of carbon dioxide to formate in this study. Using a 2% methanol concentration for induction, microbial harboring the recombinant MeFDH1 expressing plasmid produced the highest concentration of formate (26.6 mM within 21 hours) in electrochemical reactor. 60 μM of sodium tungstate in the culture medium was optimal for the expression of recombinant MeFDH1 and production of formate (25.7 mM within 21 hours). The recombinant MeFDH1 expressing cells showed maximum formate productivity of 2.53 mM/g-wet cell/hr, which was 2.5 times greater than that of wild type. Thus, M. extorquens AM1 was successfully engineered by expressing MeFDH1 as recombinant enzyme to elevate the production of formate from CO 2 after elucidating key responsible enzyme for the conversion of CO 2 to formate.

  16. Transition Organometallic Heterobimettalic Microns-Carbon Dioxide and Microns-Format Complexes in Homogeneous Carbon Dioxide Fixation

    DTIC Science & Technology

    1992-08-12

    AD-A254 538 OFFICE OF NAVAL RESEARCH FINAL REPORT FCR Contract N00014-87-K-0465 R&T Code 413j006 "Transition Organometallic Heterobimetallic ix...ransition Organometallic Heterobimetallic P-Carbon Dioxide and p-FormateComplexes in Homogeneous Carbon Dioxide Fixation 12. PERSONAL AUTHOR(S) Alan R...J. L. Shibley, and A. R. Cutler, J. Organomet. Chem. 1989,378, 421.* "Characterization of the Heterobimetallic ±(r011-C: T12 -O,O’) Carbon Dioxide

  17. Effect of dissolved carbon dioxide on penicillin fermentations: mycelial growth and penicillin production. [Penicillium chrysogenum

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Ho, C.S.; Smith, M.D.

    The effect of dissolved carbon dioxide on the specific growth rate and the penicillin production rate of Penicillium chrysogenum was examined experimentally. The dissolved carbon dioxide was found to inhibit the specific growth rate and the penicillin production rate when the aerated submerged penicillin fermentation was exposed to influent gases of 12.6 and 20% carbon dioxide, respectively. Upon exposure to influent gases of 3 and 5% carbon dioxide, no pronounced metabolic inhibition was noted.

  18. Supercritical carbon dioxide processing of active pharmaceutical ingredients for polymorphic control and for complex formation.

    PubMed

    Moribe, Kunikazu; Tozuka, Yuichi; Yamamoto, Keiji

    2008-02-14

    Supercritical fluid technique have been exploited in extraction, separation and crystallization processes. In the field of pharmaceutics, supercritical carbon dioxide (scCO(2)) has been used for the purpose of micronization, polymorphic control, and preparation of solid dispersion and complexes. Particle design of active pharmaceutical ingredients is important to make the solid dosage forms with suitable physicochemical properties. Control of the characteristic properties of particles, such as size, shape, crystal structure and morphology is required to optimize the formulation. For solubility enhancement of poorly water-soluble drugs, preparation of the solid dispersion or the complexation with proper drugs or excipients should be a promising approach. This review focuses on aspects of polymorphic control and complexation behavior of active pharmaceutical ingredients by scCO(2) processing.

  19. Carbon dioxide stripping in aquaculture. part 1: terminology and reporting

    USGS Publications Warehouse

    Colt, John; Watten, Barnaby; Pfeiffer, Tim

    2012-01-01

    The removal of carbon dioxide gas in aquacultural systems is much more complex than for oxygen or nitrogen gas because of liquid reactions of carbon dioxide and their kinetics. Almost all published carbon dioxide removal information for aquaculture is based on the apparent removal value after the CO2(aq) + HOH ⇔ H2CO3 reaction has reached equilibrium. The true carbon dioxide removal is larger than the apparent value, especially for high alkalinities and seawater. For low alkalinity freshwaters (<2000 μeq/kg), the difference between the true and apparent removal is small and can be ignored for many applications. Analytical and reporting standards are recommended to improve our understanding of carbon dioxide removal.

  20. Interstellar Communication Channel Based on a Biological Universal

    NASA Technical Reports Server (NTRS)

    Weber, Arthur L.; DeVincenzi, Donald L. (Technical Monitor)

    1999-01-01

    Cellular biosynthesis starts with sugar substrates and continues energetically downhill to yield amino acid, rapid, and nucleotide products. To understand the energetics of these processes, we calculated the energy for biosynthesis from sugars of E. cali's amino acids, nucleotides, and lipids. We found that the biosynthesis of amino acids and lipids from sugar substrates proceeds by redox disproportionation. of sugar carbon with a favorable energy of about -11 kcal/mole of carbon. Overall, redox disproportion of sugar carbon accounted for 84% and 96% (ATP only 6% and 1%) of the total biosynthetic energy of amino acids and lipids (the major cellular constituents). Next, we calculated for all 48 possible 3-carbon substrates the energy of maximal disproportionation to carbon dioxide and methane. We found no other carbon substrates than matched sugars in biosynthetic energy, efficiency, and simplicity. From this, we concluded that sugars are the optimal biosynthetic substrate. Since this conclusion is based on universal properties of carbon chemistry, other carbon-based life throughout the Universe would also use optimal sugar substrates. Furthermore, this rather obvious universal role of sugars as the optimal biosubstrate would probably be common knowledge of technological civilizations throughout the Universe. Since the elemental building block of all sugars is formaldehyde, the common knowledge that sugars are the universal optimal biosubstrate could reasonably lead to the selection of a line(s) in the microwave spectrum of formaldehyde as a frequency for interstellar communication.

  1. A strategic decision-making model considering the social costs of carbon dioxide emissions for sustainable supply chain management.

    PubMed

    Tseng, Shih-Chang; Hung, Shiu-Wan

    2014-01-15

    Incorporating sustainability into supply chain management has become a critical issue driven by pressures from governments, customers, and various stakeholder groups over the past decade. This study proposes a strategic decision-making model considering both the operational costs and social costs caused by the carbon dioxide emissions from operating such a supply chain network for sustainable supply chain management. This model was used to evaluate carbon dioxide emissions and operational costs under different scenarios in an apparel manufacturing supply chain network. The results showed that the higher the social cost rate of carbon dioxide emissions, the lower the amount of the emission of carbon dioxide. The results also suggested that a legislation that forces the enterprises to bear the social costs of carbon dioxide emissions resulting from their economic activities is an effective approach to reducing carbon dioxide emissions. Copyright © 2013 Elsevier Ltd. All rights reserved.

  2. Semiconductor-Based Photoelectrochemical Conversion of Carbon Dioxide: Stepping Towards Artificial Photosynthesis.

    PubMed

    Pang, Hong; Masuda, Takuya; Ye, Jinhua

    2018-01-18

    The photoelectrochemical (PEC) carbon dioxide reduction process stands out as a promising avenue for the conversion of solar energy into chemical feedstocks, among various methods available for carbon dioxide mitigation. Semiconductors derived from cheap and abundant elements are interesting candidates for catalysis. Whether employed as intrinsic semiconductors or hybridized with metallic cocatalysts, biocatalysts, and metal molecular complexes, semiconductor photocathodes exhibit good performance and low overpotential during carbon dioxide reduction. Apart from focusing on carbon dioxide reduction materials and chemistry, PEC cells towards standalone devices that use photohybrid electrodes or solar cells have also been a hot topic in recent research. An overview of the state-of-the-art progress in PEC carbon dioxide reduction is presented and a deep understanding of the catalysts of carbon dioxide reduction is also given. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

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

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Edwards, A.G.; Ho, C.S.

    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 ofmore » 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.« less

  4. Application of biogenic carbon dioxide produced by yeast with different carbon sources for attraction of mosquitoes towards adult mosquito traps.

    PubMed

    Sukumaran, D; Ponmariappan, S; Sharma, Atul K; Jha, Hemendra K; Wasu, Yogesh H; Sharma, Ajay K

    2016-04-01

    Surveillance is a prime requisite for controlling arthropod vectors like mosquitoes that transmit diseases such as malaria, dengue and chikungunya. Carbon dioxide (CO2) is one of the main cues from vertebrate breath that attracts mosquitoes towards the host. Hence, CO2 is used as an attractant during surveillance of mosquitoes either from commercial cylinders or dry ice for mosquito traps. In the present study, the biogenic carbon dioxide production was optimized with different carbon sources such as glucose, simple sugar and jaggery with and without yeast peptone dextrose (YPD) media using commercial baker's yeast. The results showed that yeast produced more biogenic CO2 with simple sugar as compared to other carbon sources. Further substrate concentration was optimized for the continuous production of biogenic CO2 for a minimum of 12 h by using 10 g of baker's yeast with 50 g of simple sugar added to 1.5 l distilled water (without YPD media) in a 2-l plastic bottle. This setup was applied in field condition along with two different mosquito traps namely Mosquito Killing System (MKS) and Biogents Sentinel (BGS) trap. Biogenic CO2 from this setup has increased the trapping efficiency of MKS by 6.48-fold for Culex quinquefasciatus, 2.62-fold for Aedes albopictus and 1.5-fold for Anopheles stephensi. In the case of BGS, the efficiency was found to be increased by 3.54-fold for Ae. albopictus, 4.33-fold for An. stephensi and 1.3-fold for Armigeres subalbatus mosquitoes. On the whole, plastic bottle setup releasing biogenic CO2 from sugar and yeast has increased the efficiency of MKS traps by 6.38-fold and 2.74-fold for BGS traps as compared to traps without biogenic CO2. The present study reveals that, among different carbon sources used, simple sugar as a substance (which is economical and readily available across the world) yielded maximum biogenic CO2 with yeast. This setup can be used as an alternative to CO2 cylinder and dry ice in any adult mosquito traps to enhance their trapping efficiency of a mosquito surveillance programme.

  5. The Formation of Ethane from Carbon Dioxide under Cold Plasma

    NASA Astrophysics Data System (ADS)

    Zhang, Xiu-ling; Zhang, Lin; Dai, Bin; Gong, Wei-min; Liu, Chang-hou

    2001-04-01

    Pulsed-corona plasma has been used as a new method for ethane dehydrogenation at low temperature and normal pressure using carbon dioxide as an oxidant in this paper. The effect of carbon dioxide content in the feed, power input, and flow rate of the reactants on the ethane dehydrogenation has been investigated. The experimental results show that the conversion of ethane increases with the increase in the amount of carbon dioxide in the feed. The yield of ethylene and acetylene decreases with the increase in the yield of carbon monoxide, indicating that the increased carbon dioxide leads to the part of ethylene and acetylene being oxidized to carbon monoxide. Power input is primarily an electrical parameter in pulsed-corona plasma, which plays an important role in reactant conversion and product formation. When the power input reaches 16 W, ethane conversion is 41.0% and carbon dioxide conversion is 26.3%. The total yield of ethylene and acetylene is 15.6%. The reduced flow rate of feed improves the conversion of ethane, carbon dioxide and the yield of acetylene, and induces carbon deposit as well.

  6. 21 CFR 868.2480 - Cutaneous carbon dioxide (PcCO2) monitor.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Cutaneous carbon dioxide (PcCO2) monitor. 868.2480... (CONTINUED) MEDICAL DEVICES ANESTHESIOLOGY DEVICES Monitoring Devices § 868.2480 Cutaneous carbon dioxide (PcCO2) monitor. (a) Identification. A cutaneous carbon dioxide (PcCO2) monitor is a noninvasive heated...

  7. 40 CFR 180.1049 - Carbon dioxide; exemption from the requirement of a tolerance.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 23 2010-07-01 2010-07-01 false Carbon dioxide; exemption from the... Exemptions From Tolerances § 180.1049 Carbon dioxide; exemption from the requirement of a tolerance. The insecticide carbon dioxide is exempted from the requirement of a tolerance when used after harvest in modified...

  8. 21 CFR 868.5310 - Carbon dioxide absorber.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Carbon dioxide absorber. 868.5310 Section 868.5310...) MEDICAL DEVICES ANESTHESIOLOGY DEVICES Therapeutic Devices § 868.5310 Carbon dioxide absorber. (a) Identification. A carbon dioxide absorber is a device that is intended for medical purposes and that is used in a...

  9. 21 CFR 868.5310 - Carbon dioxide absorber.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Carbon dioxide absorber. 868.5310 Section 868.5310...) MEDICAL DEVICES ANESTHESIOLOGY DEVICES Therapeutic Devices § 868.5310 Carbon dioxide absorber. (a) Identification. A carbon dioxide absorber is a device that is intended for medical purposes and that is used in a...

  10. 21 CFR 201.161 - Carbon dioxide and certain other gases.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 4 2014-04-01 2014-04-01 false Carbon dioxide and certain other gases. 201.161... (CONTINUED) DRUGS: GENERAL LABELING Other Exemptions § 201.161 Carbon dioxide and certain other gases. (a) Carbon dioxide, cyclopropane, ethylene, helium, and nitrous oxide gases intended for drug use are...

  11. 27 CFR 26.222 - Still wines containing carbon dioxide.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... carbon dioxide. 26.222 Section 26.222 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND... ISLANDS Formulas for Products From the Virgin Islands § 26.222 Still wines containing carbon dioxide. (a) General. Still wines may contain not more than 0.392 gram of carbon dioxide per 100 milliliters of wine...

  12. 27 CFR 26.222 - Still wines containing carbon dioxide.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... carbon dioxide. 26.222 Section 26.222 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND... ISLANDS Formulas for Products From the Virgin Islands § 26.222 Still wines containing carbon dioxide. (a) General. Still wines may contain not more than 0.392 gram of carbon dioxide per 100 milliliters of wine...

  13. 40 CFR 180.1049 - Carbon dioxide; exemption from the requirement of a tolerance.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 24 2014-07-01 2014-07-01 false Carbon dioxide; exemption from the... Exemptions From Tolerances § 180.1049 Carbon dioxide; exemption from the requirement of a tolerance. The insecticide carbon dioxide is exempted from the requirement of a tolerance when used after harvest in modified...

  14. 21 CFR 201.161 - Carbon dioxide and certain other gases.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 4 2013-04-01 2013-04-01 false Carbon dioxide and certain other gases. 201.161... (CONTINUED) DRUGS: GENERAL LABELING Other Exemptions § 201.161 Carbon dioxide and certain other gases. (a) Carbon dioxide, cyclopropane, ethylene, helium, and nitrous oxide gases intended for drug use are...

  15. 21 CFR 868.5310 - Carbon dioxide absorber.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Carbon dioxide absorber. 868.5310 Section 868.5310...) MEDICAL DEVICES ANESTHESIOLOGY DEVICES Therapeutic Devices § 868.5310 Carbon dioxide absorber. (a) Identification. A carbon dioxide absorber is a device that is intended for medical purposes and that is used in a...

  16. 27 CFR 26.222 - Still wines containing carbon dioxide.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... carbon dioxide. 26.222 Section 26.222 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND... ISLANDS Formulas for Products From the Virgin Islands § 26.222 Still wines containing carbon dioxide. (a) General. Still wines may contain not more than 0.392 gram of carbon dioxide per 100 milliliters of wine...

  17. 21 CFR 868.1150 - Indwelling blood carbon dioxide partial pressure (PCO2) analyzer.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Indwelling blood carbon dioxide partial pressure....1150 Indwelling blood carbon dioxide partial pressure (PCO2) analyzer. (a) Identification. An indwelling blood carbon dioxide partial pressure PCO2 analyzer is a device that consists of a catheter-tip...

  18. 21 CFR 868.1150 - Indwelling blood carbon dioxide partial pressure (PCO2) analyzer.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Indwelling blood carbon dioxide partial pressure....1150 Indwelling blood carbon dioxide partial pressure (PCO2) analyzer. (a) Identification. An indwelling blood carbon dioxide partial pressure PCO2 analyzer is a device that consists of a catheter-tip...

  19. 21 CFR 868.1150 - Indwelling blood carbon dioxide partial pressure (PCO2) analyzer.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Indwelling blood carbon dioxide partial pressure....1150 Indwelling blood carbon dioxide partial pressure (PCO2) analyzer. (a) Identification. An indwelling blood carbon dioxide partial pressure PCO2 analyzer is a device that consists of a catheter-tip...

  20. 21 CFR 868.1150 - Indwelling blood carbon dioxide partial pressure (PCO2) analyzer.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Indwelling blood carbon dioxide partial pressure....1150 Indwelling blood carbon dioxide partial pressure (PCO2) analyzer. (a) Identification. An indwelling blood carbon dioxide partial pressure PCO2 analyzer is a device that consists of a catheter-tip...

  1. 21 CFR 868.5310 - Carbon dioxide absorber.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Carbon dioxide absorber. 868.5310 Section 868.5310 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES ANESTHESIOLOGY DEVICES Therapeutic Devices § 868.5310 Carbon dioxide absorber. (a) Identification. A carbon dioxide absorber is a devic...

  2. 46 CFR 169.565 - Fixed carbon dioxide system.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 7 2012-10-01 2012-10-01 false Fixed carbon dioxide system. 169.565 Section 169.565 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) NAUTICAL SCHOOLS SAILING SCHOOL VESSELS Lifesaving and Firefighting Equipment Firefighting Equipment § 169.565 Fixed carbon dioxide system. (a) The number of pounds of carbon dioxide...

  3. 46 CFR 108.431 - Carbon dioxide systems: General.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 4 2013-10-01 2013-10-01 false Carbon dioxide systems: General. 108.431 Section 108.431 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) A-MOBILE OFFSHORE DRILLING UNITS DESIGN AND EQUIPMENT Fire Extinguishing Systems Fixed Carbon Dioxide Fire Extinguishing Systems § 108.431 Carbon dioxide systems: General. (a)...

  4. 46 CFR 169.565 - Fixed carbon dioxide system.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 7 2013-10-01 2013-10-01 false Fixed carbon dioxide system. 169.565 Section 169.565 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) NAUTICAL SCHOOLS SAILING SCHOOL VESSELS Lifesaving and Firefighting Equipment Firefighting Equipment § 169.565 Fixed carbon dioxide system. (a) The number of pounds of carbon dioxide...

  5. 46 CFR 108.431 - Carbon dioxide systems: General.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 4 2011-10-01 2011-10-01 false Carbon dioxide systems: General. 108.431 Section 108.431 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) A-MOBILE OFFSHORE DRILLING UNITS DESIGN AND EQUIPMENT Fire Extinguishing Systems Fixed Carbon Dioxide Fire Extinguishing Systems § 108.431 Carbon dioxide systems: General. (a)...

  6. 21 CFR 868.1400 - Carbon dioxide gas analyzer.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Carbon dioxide gas analyzer. 868.1400 Section 868.1400 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES ANESTHESIOLOGY DEVICES Diagnostic Devices § 868.1400 Carbon dioxide gas analyzer. (a) Identification. A carbon dioxide gas analyzer...

  7. 46 CFR 193.15-20 - Carbon dioxide storage.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 7 2012-10-01 2012-10-01 false Carbon dioxide storage. 193.15-20 Section 193.15-20 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS FIRE PROTECTION EQUIPMENT Carbon Dioxide and Clean Agent Extinguishing Systems, Details § 193.15-20 Carbon dioxide storage. (a) Except as provided in...

  8. 46 CFR 108.627 - Carbon dioxide alarm.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 4 2011-10-01 2011-10-01 false Carbon dioxide alarm. 108.627 Section 108.627 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) A-MOBILE OFFSHORE DRILLING UNITS DESIGN AND EQUIPMENT Equipment Markings and Instructions § 108.627 Carbon dioxide alarm. Each carbon dioxide alarm must be identified by marking: “WHEN ALARM...

  9. 46 CFR 108.431 - Carbon dioxide systems: General.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 4 2012-10-01 2012-10-01 false Carbon dioxide systems: General. 108.431 Section 108.431 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) A-MOBILE OFFSHORE DRILLING UNITS DESIGN AND EQUIPMENT Fire Extinguishing Systems Fixed Carbon Dioxide Fire Extinguishing Systems § 108.431 Carbon dioxide systems: General. (a)...

  10. 46 CFR 108.431 - Carbon dioxide systems: General.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 4 2014-10-01 2014-10-01 false Carbon dioxide systems: General. 108.431 Section 108.431 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) A-MOBILE OFFSHORE DRILLING UNITS DESIGN AND EQUIPMENT Fire Extinguishing Systems Fixed Carbon Dioxide Fire Extinguishing Systems § 108.431 Carbon dioxide systems: General. (a)...

  11. 46 CFR 169.565 - Fixed carbon dioxide system.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 7 2014-10-01 2014-10-01 false Fixed carbon dioxide system. 169.565 Section 169.565 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) NAUTICAL SCHOOLS SAILING SCHOOL VESSELS Lifesaving and Firefighting Equipment Firefighting Equipment § 169.565 Fixed carbon dioxide system. (a) The number of pounds of carbon dioxide...

  12. 21 CFR 868.5300 - Carbon dioxide absorbent.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Carbon dioxide absorbent. 868.5300 Section 868.5300 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES ANESTHESIOLOGY DEVICES Therapeutic Devices § 868.5300 Carbon dioxide absorbent. (a) Identification. A carbon dioxide absorbent is a...

  13. 21 CFR 868.5300 - Carbon dioxide absorbent.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Carbon dioxide absorbent. 868.5300 Section 868.5300 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES ANESTHESIOLOGY DEVICES Therapeutic Devices § 868.5300 Carbon dioxide absorbent. (a) Identification. A carbon dioxide absorbent is a...

  14. 21 CFR 868.5310 - Carbon dioxide absorber.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Carbon dioxide absorber. 868.5310 Section 868.5310 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES ANESTHESIOLOGY DEVICES Therapeutic Devices § 868.5310 Carbon dioxide absorber. (a) Identification. A carbon dioxide absorber is a devic...

  15. 27 CFR 26.222 - Still wines containing carbon dioxide.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... carbon dioxide. 26.222 Section 26.222 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND... ISLANDS Formulas for Products From the Virgin Islands § 26.222 Still wines containing carbon dioxide. (a) General. Still wines may contain not more than 0.392 gram of carbon dioxide per 100 milliliters of wine...

  16. Process for sequestering carbon dioxide and sulfur dioxide

    DOEpatents

    Maroto-Valer, M Mercedes [State College, PA; Zhang, Yinzhi [State College, PA; Kuchta, Matthew E [State College, PA; Andresen, John M [State College, PA; Fauth, Dan J [Pittsburgh, PA

    2009-10-20

    A process for sequestering carbon dioxide, which includes reacting a silicate based material with an acid to form a suspension, and combining the suspension with carbon dioxide to create active carbonation of the silicate-based material, and thereafter producing a metal salt, silica and regenerating the acid in the liquid phase of the suspension.

  17. Effect of Carbon Dioxide on Testing of Susceptibilities of Respiratory Tract Pathogens to Macrolide and Azalide Antimicrobial Agents

    PubMed Central

    Johnson, M. M.; Hill, S. L.; Piddock, Laura J. V.

    1999-01-01

    The in vitro activities of erythromycin, azithromycin, and clarithromycin against 178 clinical isolates from the lower respiratory tract of patients with chronic obstructive pulmonary disease were determined by an agar dilution method. The plates were incubated in air alone or in 5% carbon dioxide. The MICs measured in air alone were lower for most isolates than those measured in 5% carbon dioxide, illustrating the “pH effect” of incubation in carbon dioxide. Testing of isolates in 5% carbon dioxide on pH-adjusted medium (pH 8.4) resulted in MICs of one or two doubling dilutions lower than those obtained on agar with a neutral pH. A bioassay of the three agents incubated in air and in 5% carbon dioxide resulted in a significant loss of activity of all three agents in the carbon dioxide-enriched atmosphere. However, this loss-of-activity effect was significantly reduced when the bioassay medium was adjusted to pH 8.4 prior to incubation in 5% carbon dioxide. PMID:10428903

  18. Elevated atmospheric carbon dioxide concentration affects interactions between Spodoptera exigua (Lepidoptera: Noctuidae) larvae and two host plant species outdoors

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Caulfield, F.; Bunce, J.A.

    1994-08-01

    Beet armyworm, Spodoptera exigua (Huebner), larvae were placed on sugarbeet (Beta vulgaris L.) and pigweed (Amaranthus hybridus L.) plants in outdoor chambers in which the plants were growing at either the ambient ([approximately] 350 [mu]l liter[sup [minus]1]) or ambient plus 350 [mu]l liter[sup [minus]1] ([approximately] 700 [mu]l liter[sup [minus]1]) carbon dioxide concentration. A series of experiments was performed to determine if larvae reduced plant growth differently at the two carbon dioxide concentrations in either species and if the insect growth or survival differed with carbon dioxide concentration. Leaf nitrogen, water, starch, and soluble carbohydrate contents were measured to assess carbonmore » dioxide concentration effects on leaf quality. Insect feeding significantly reduced plant growth in sugarbeet plants at 350 [mu]l liter[sup [minus]1] but not at 700 [mu]l liter[sup [minus]1] nor in pigweed at either carbon dioxide concentration. Larval survival was greater on sugarbeet plants at the elevated carbon dioxide concentration. Increased survival occurred only if the insects were at the elevated carbon dioxide concentration and consumed leaf material grown at the elevated concentration. Leaf quality was only marginally affected by growth at elevated carbon dioxide concentration in these experiments. The results indicate that in designing experiments to predict effects of elevated atmospheric carbon dioxide concentrations on plant-insect interactions, both plants and insects should be exposed to the experimental carbon dioxide concentrations, as well as to as realistic environmental conditions as possible.« less

  19. 40 CFR 86.316-79 - Carbon monoxide and carbon dioxide analyzer specifications.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 18 2011-07-01 2011-07-01 false Carbon monoxide and carbon dioxide... AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) CONTROL OF EMISSIONS FROM NEW AND IN-USE HIGHWAY VEHICLES AND... Test Procedures § 86.316-79 Carbon monoxide and carbon dioxide analyzer specifications. (a) Carbon...

  20. A metal-free electrocatalyst for carbon dioxide reduction to multi-carbon hydrocarbons and oxygenates

    PubMed Central

    Wu, Jingjie; Ma, Sichao; Sun, Jing; Gold, Jake I.; Tiwary, ChandraSekhar; Kim, Byoungsu; Zhu, Lingyang; Chopra, Nitin; Odeh, Ihab N.; Vajtai, Robert; Yu, Aaron Z.; Luo, Raymond; Lou, Jun; Ding, Guqiao; Kenis, Paul J. A.; Ajayan, Pulickel M.

    2016-01-01

    Electroreduction of carbon dioxide into higher-energy liquid fuels and chemicals is a promising but challenging renewable energy conversion technology. Among the electrocatalysts screened so far for carbon dioxide reduction, which includes metals, alloys, organometallics, layered materials and carbon nanostructures, only copper exhibits selectivity towards formation of hydrocarbons and multi-carbon oxygenates at fairly high efficiencies, whereas most others favour production of carbon monoxide or formate. Here we report that nanometre-size N-doped graphene quantum dots (NGQDs) catalyse the electrochemical reduction of carbon dioxide into multi-carbon hydrocarbons and oxygenates at high Faradaic efficiencies, high current densities and low overpotentials. The NGQDs show a high total Faradaic efficiency of carbon dioxide reduction of up to 90%, with selectivity for ethylene and ethanol conversions reaching 45%. The C2 and C3 product distribution and production rate for NGQD-catalysed carbon dioxide reduction is comparable to those obtained with copper nanoparticle-based electrocatalysts. PMID:27958290

  1. High Temperature Raman Spectroscopy Study of the Conversion of Formate into Oxalate: Search for the Elusive CO 2 2 - Intermediate

    NASA Astrophysics Data System (ADS)

    Ryan, Charles; Mead, Anna; Lakkaraju, Prasad; Kaczur, Jerry; Bennett, Christopher; Dobbins, Tabbetha

    Research on conversion of carbon dioxide into chemicals and fuels has the potential to address three problems of global relevance. (a) By removing carbon dioxide from the atmosphere, we are able to reduce the amount of greenhouse gases in the atmosphere, (b) by converting carbon dioxide into fuels, we are providing pathways for renewable energy sources, (c) by converting carbon dioxide into C2 and higher order compounds, and we are able to generate valuable precursors for organic synthesis. Formate salts are formed by the electrochemical reduction of carbon dioxide in aqueous media. However, in order to increase the utilization of carbon dioxide, methods need to be developed for the conversion of formate into compounds containing two carbon atoms such as oxalate or oxalic acid. Recently, we examined the thermal conversion of sodium formate into sodium oxalate utilizing a hydride ion catalyst. The proposed mechanism for this reaction involves the carbon dioxide dianion. Currently at NASA Goddard Space Flight Center.

  2. Oxygen and Carbon Dioxide Fluxes from Barley Shoots Depend on Nitrate Assimilation 1

    PubMed Central

    Bloom, Arnold J.; Caldwell, Richard M.; Finazzo, John; Warner, Robert L.; Weissbart, Joseph

    1989-01-01

    A custom oxygen analyzer in conjunction with an infrared carbon dioxide analyzer and humidity sensors permitted simultaneous measurements of oxygen, carbon dioxide, and water vapor fluxes from the shoots of intact barley plants (Hordeum vulgare L. cv Steptoe). The oxygen analyzer is based on a calciazirconium sensor and can resolve concentration differences to within 2 microliters per liter against the normal background of 210,000 microliters per liter. In wild-type plants receiving ammonium as their sole nitrogen source or in nitrate reductase-deficient mutants, photosynthetic and respiratory fluxes of oxygen equaled those of carbon dioxide. By contrast, wild-type plants exposed to nitrate had unequal oxygen and carbon dioxide fluxes: oxygen evolution at high light exceeded carbon dioxide consumption by 26% and carbon dioxide evolution in the dark exceeded oxygen consumption by 25%. These results indicate that a substantial portion of photosynthetic electron transport or respiration generates reductant for nitrate assimilation rather than for carbon fixation or mitochondrial electron transport. PMID:16667024

  3. The influence of deep-seabed CO2 sequestration on small metazoan (meiofaunal) viability and community structure: final technical report

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Thistle, D

    2008-09-30

    Since the industrial revolution, the burning of fossil fuel has produced carbon dioxide at an increasing rate. Present atmospheric concentration is about ~1.5 times the preindustrial level and is rising. Because carbon dioxide is a greenhouse gas, its increased concentration in the atmosphere is thought to be a cause of global warming. If so, the rate of global warming could be slowed if industrial carbon dioxide were not released into the atmosphere. One suggestion has been to sequester it in the deep ocean, but theory predicts that deep-sea species will be intolerant of the increased concentrations of carbon dioxide andmore » the increased acidity it would cause. The aim of our research was to test for consequences of carbon dioxide sequestration on deep-sea, sediment-dwelling meiofauna. Recent technical advances allowed us to test for effects in situ at depths proposed for sequestration. The basic experimental unit was an open-topped container into which we pumped ~20 L of liquid carbon dioxide. The liquid carbon dioxide mixed with near-bottom sea water, which produced carbon dioxide-rich sea water that flowed out over the near-by seabed. We did 30-day experiments at several locations and with different numbers of carbon dioxide-filled containers. Harpacticoid copepods (Crustacea) were our test taxon. In an experiment we did during a previous grant period, we found that large numbers of individuals exposed to carbon dioxide-rich sea water had been killed (Thistle et al. 2004). During the present grant period, we analyzed the species-level data in greater detail and discovered that, although individuals of many species had been killed by exposure to carbon dioxide-rich sea water, individuals of some species had not (Thistle et al. 2005). This result suggests that seabed sequestration of carbon dioxide will not just reduce the abundance of the meiofauna but will change the composition of the community. In another experiment, we found that some harpacticoid species swim away from an advancing front of carbon dioxide-rich sea water (Thistle et al. 2007). This result demonstrates a second way that deep-sea meiofauna react negatively to carbon dioxide-rich sea water. In summary, we used in situ experiments to show that carbon dioxide-rich sea water triggers an escape response in some harpacticoid species. It kills most individuals of most harpacticoid species that do not flee, but a few species seem to be unaffected. Proposals to reduce global warming by sequestering industrial carbon dioxide in the deep ocean should take note of these environmental consequences when pros and cons are weighed.« less

  4. X-ray CT for quantitative food microstructure engineering: The apple case

    NASA Astrophysics Data System (ADS)

    Herremans, Els; Verboven, Pieter; Defraeye, Thijs; Rogge, Seppe; Ho, Quang Tri; Hertog, Maarten L. A. T. M.; Verlinden, Bert E.; Bongaers, Evi; Wevers, Martine; Nicolai, Bart M.

    2014-04-01

    Apple fruit is a major crop that can be supplied year-round due to low temperature storage in a controlled atmosphere with a reduced oxygen concentration and an increased carbon dioxide concentration. The low temperature and dedicated gas concentration levels are designed to provide optimal conditions that prevent ripening while maintaining the fundamental respiratory metabolism necessary for energy supply in the cells that ensures cell and tissue integrity during storage of the fruit. If the concentration of oxygen is too low or that of carbon dioxide too high, a fermentation metabolism is induced that causes the production of off-flavours, results in insufficient energy supply, leading to cell collapse and consequent tissue browning and cavity formation. The microstructural arrangement of cells and intercellular spaces in the apple create specific pathways for transport of the respiratory gasses oxygen and carbon dioxide. We used X-ray CT to characterise the changes in the microstructure of ‘Braeburn’ apple during the development of internal storage disorders. Multiscale modeling was applied to understand the changes in oxygen and carbon dioxide concentrations and respiration and fermentation rates in the apple during the disorder development in controlled atmosphere storage of ‘Braeburn’ apple fruit. The 3D microstructure geometries of healthy, brown tissue and tissue with cavities were created to solve the micro-scale gas-exchange model for O2 and CO2 using the finite volume method. The apparent gas diffusivities of the tissue were calculated and implemented in the macroscale geometry of healthy and disordered apples to study in detail the changes in the respiratory metabolism of the fruit.

  5. Antimicrobial Cream Formulated with Supercritical Carbon Dioxide Extract of Tuberose Flowers Arrests Growth of Staphylococcus aureus.

    PubMed

    Ghosh, Probir Kumar; Bhattacharjee, Paramita; Das, Satadal

    2016-01-01

    Antimicrobial potency of herbal extracts is well known. The review of patents and research articles revealed that several herbal extracts have been employed in the formulation of topical products such as creams, exclusive of the cream reported in the present study. 0ur previous study has established antimicrobial potency of supercritical carbon dioxide extracts of tuberose flowers, better known for its sweet fragrance. The present work focuses on formulating a topical antimicrobial herbal cream with methyl eugenol (principal antimicrobial compound) rich - supercritical carbon dioxide extract of tuberose flowers, having good combination of phytochemical and antimicrobial potencies. Supercritical carbon dioxide parameters such as temperature, pressure and time were optimized using full factorial experimental design to obtain methyl eugenol-rich extracts. A cream was formulated using the extract having the best combination of phytochemical and antimicrobial potencies and was assayed further for in vitro antimicrobial potency; physiochemical and sensory properties. Two commercial antimicrobial cream samples were used as reference samples in the study. The extract obtained at 40°C, 10 MPa, 135 min at 1 L min-1 flow rate of gaseous C02 showed the best combination of phytochemical and antimicrobial potencies and was used for formulation of herbal creams. The cream formulated with 5% w/w of extract arrested growth of the common human skin pathogen Staphylococcus aureus and showed stable physiochemical properties and high sensory appeal for a year. The cream could be considered as a 'finished herbal product&' in compliance with the World Health 0rganization guidelines.

  6. 46 CFR 34.15-20 - Carbon dioxide storage-T/ALL.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 1 2011-10-01 2011-10-01 false Carbon dioxide storage-T/ALL. 34.15-20 Section 34.15-20 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY TANK VESSELS FIREFIGHTING EQUIPMENT Carbon Dioxide Extinguishing Systems, Details § 34.15-20 Carbon dioxide storage—T/ALL. (a) Except as provided in paragraph (b...

  7. 46 CFR 35.40-7 - Carbon dioxide alarm-T/ALL.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 1 2011-10-01 2011-10-01 false Carbon dioxide alarm-T/ALL. 35.40-7 Section 35.40-7 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY TANK VESSELS OPERATIONS Posting and Marking Requirements-TB/ALL. § 35.40-7 Carbon dioxide alarm—T/ALL. Adjacent to all carbon dioxide fire extinguishing...

  8. 46 CFR 34.15-20 - Carbon dioxide storage-T/ALL.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 1 2010-10-01 2010-10-01 false Carbon dioxide storage-T/ALL. 34.15-20 Section 34.15-20 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY TANK VESSELS FIREFIGHTING EQUIPMENT Carbon Dioxide Extinguishing Systems, Details § 34.15-20 Carbon dioxide storage—T/ALL. (a) Except as provided in paragraph (b...

  9. 46 CFR 34.15-20 - Carbon dioxide storage-T/ALL.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 1 2014-10-01 2014-10-01 false Carbon dioxide storage-T/ALL. 34.15-20 Section 34.15-20 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY TANK VESSELS FIREFIGHTING EQUIPMENT Carbon Dioxide Extinguishing Systems, Details § 34.15-20 Carbon dioxide storage—T/ALL. (a) Except as provided in paragraph (b...

  10. 46 CFR 34.15-20 - Carbon dioxide storage-T/ALL.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 1 2013-10-01 2013-10-01 false Carbon dioxide storage-T/ALL. 34.15-20 Section 34.15-20 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY TANK VESSELS FIREFIGHTING EQUIPMENT Carbon Dioxide Extinguishing Systems, Details § 34.15-20 Carbon dioxide storage—T/ALL. (a) Except as provided in paragraph (b...

  11. 27 CFR 27.42a - Still wines containing carbon dioxide.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    .... Still wines may contain not more than 0.392 gram of carbon dioxide per 100 milliliters of wine; except that a tolerance to this maximum limitation, not to exceed 0.009 gram of carbon dioxide per 100 milliliters of wine, will be allowed where the amount of carbon dioxide in excess of 0.392 gram per 100...

  12. 27 CFR 24.245 - Use of carbon dioxide in still wine.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... than 0.392 grams of carbon dioxide per 100 milliliters of wine. However, a tolerance of not more than 0.009 grams per 100 milliliters to the maximum limitation of carbon dioxide in still wine will be allowed where the amount of carbon dioxide in excess of 0.392 grams per 100 milliliters is due to...

  13. 27 CFR 27.42a - Still wines containing carbon dioxide.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    .... Still wines may contain not more than 0.392 gram of carbon dioxide per 100 milliliters of wine; except that a tolerance to this maximum limitation, not to exceed 0.009 gram of carbon dioxide per 100 milliliters of wine, will be allowed where the amount of carbon dioxide in excess of 0.392 gram per 100...

  14. 27 CFR 27.42a - Still wines containing carbon dioxide.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    .... Still wines may contain not more than 0.392 gram of carbon dioxide per 100 milliliters of wine; except that a tolerance to this maximum limitation, not to exceed 0.009 gram of carbon dioxide per 100 milliliters of wine, will be allowed where the amount of carbon dioxide in excess of 0.392 gram per 100...

  15. 27 CFR 27.42a - Still wines containing carbon dioxide.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    .... Still wines may contain not more than 0.392 gram of carbon dioxide per 100 milliliters of wine; except that a tolerance to this maximum limitation, not to exceed 0.009 gram of carbon dioxide per 100 milliliters of wine, will be allowed where the amount of carbon dioxide in excess of 0.392 gram per 100...

  16. 27 CFR 27.42a - Still wines containing carbon dioxide.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    .... Still wines may contain not more than 0.392 gram of carbon dioxide per 100 milliliters of wine; except that a tolerance to this maximum limitation, not to exceed 0.009 gram of carbon dioxide per 100 milliliters of wine, will be allowed where the amount of carbon dioxide in excess of 0.392 gram per 100...

  17. 27 CFR 24.245 - Use of carbon dioxide in still wine.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... than 0.392 grams of carbon dioxide per 100 milliliters of wine. However, a tolerance of not more than 0.009 grams per 100 milliliters to the maximum limitation of carbon dioxide in still wine will be allowed where the amount of carbon dioxide in excess of 0.392 grams per 100 milliliters is due to...

  18. 21 CFR 201.161 - Carbon dioxide and certain other gases.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 4 2011-04-01 2011-04-01 false Carbon dioxide and certain other gases. 201.161 Section 201.161 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) DRUGS: GENERAL LABELING Other Exemptions § 201.161 Carbon dioxide and certain other gases. (a) Carbon dioxide, cyclopropane, ethylene,...

  19. 46 CFR 108.627 - Carbon dioxide and clean agent alarms.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 4 2014-10-01 2014-10-01 false Carbon dioxide and clean agent alarms. 108.627 Section 108.627 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) A-MOBILE OFFSHORE DRILLING UNITS DESIGN AND EQUIPMENT Equipment Markings and Instructions § 108.627 Carbon dioxide and clean agent alarms. Each carbon dioxide alarm must be...

  20. 46 CFR 169.732 - Carbon dioxide and clean agent alarms.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 7 2012-10-01 2012-10-01 false Carbon dioxide and clean agent alarms. 169.732 Section 169.732 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) NAUTICAL SCHOOLS SAILING SCHOOL VESSELS Vessel Control, Miscellaneous Systems, and Equipment Markings § 169.732 Carbon dioxide and clean agent alarms. (a) Each carbon dioxide o...

  1. 46 CFR 169.732 - Carbon dioxide and clean agent alarms.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 7 2013-10-01 2013-10-01 false Carbon dioxide and clean agent alarms. 169.732 Section 169.732 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) NAUTICAL SCHOOLS SAILING SCHOOL VESSELS Vessel Control, Miscellaneous Systems, and Equipment Markings § 169.732 Carbon dioxide and clean agent alarms. (a) Each carbon dioxide o...

  2. 46 CFR 108.627 - Carbon dioxide and clean agent alarms.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 4 2012-10-01 2012-10-01 false Carbon dioxide and clean agent alarms. 108.627 Section 108.627 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) A-MOBILE OFFSHORE DRILLING UNITS DESIGN AND EQUIPMENT Equipment Markings and Instructions § 108.627 Carbon dioxide and clean agent alarms. Each carbon dioxide alarm must be...

  3. 46 CFR 97.37-9 - Carbon dioxide alarm.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 4 2011-10-01 2011-10-01 false Carbon dioxide alarm. 97.37-9 Section 97.37-9 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) CARGO AND MISCELLANEOUS VESSELS OPERATIONS Markings for Fire and Emergency Equipment, Etc. § 97.37-9 Carbon dioxide alarm. (a) All carbon dioxide alarms shall be conspicuously identified: “WHEN...

  4. 46 CFR 95.15-20 - Carbon dioxide storage.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 4 2013-10-01 2013-10-01 false Carbon dioxide storage. 95.15-20 Section 95.15-20 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) CARGO AND MISCELLANEOUS VESSELS FIRE PROTECTION EQUIPMENT Carbon Dioxide Extinguishing Systems, Details § 95.15-20 Carbon dioxide storage. (a) Except as provided in paragraph (b) of this...

  5. 46 CFR 78.47-9 - Carbon dioxide alarm.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 3 2011-10-01 2011-10-01 false Carbon dioxide alarm. 78.47-9 Section 78.47-9 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) PASSENGER VESSELS OPERATIONS Markings for Fire and Emergency Equipment, Etc. § 78.47-9 Carbon dioxide alarm. (a) All carbon dioxide alarms shall be conspicuously identified: “WHEN ALARM...

  6. 46 CFR 169.732 - Carbon dioxide and clean agent alarms.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 7 2014-10-01 2014-10-01 false Carbon dioxide and clean agent alarms. 169.732 Section 169.732 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) NAUTICAL SCHOOLS SAILING SCHOOL VESSELS Vessel Control, Miscellaneous Systems, and Equipment Markings § 169.732 Carbon dioxide and clean agent alarms. (a) Each carbon dioxide o...

  7. 46 CFR 95.15-20 - Carbon dioxide storage.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 4 2014-10-01 2014-10-01 false Carbon dioxide storage. 95.15-20 Section 95.15-20 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) CARGO AND MISCELLANEOUS VESSELS FIRE PROTECTION EQUIPMENT Carbon Dioxide Extinguishing Systems, Details § 95.15-20 Carbon dioxide storage. (a) Except as provided in paragraph (b) of this...

  8. 21 CFR 201.161 - Carbon dioxide and certain other gases.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 4 2012-04-01 2012-04-01 false Carbon dioxide and certain other gases. 201.161 Section 201.161 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) DRUGS: GENERAL LABELING Other Exemptions § 201.161 Carbon dioxide and certain other gases. (a) Carbon dioxide, cyclopropane, ethylene,...

  9. 46 CFR 131.815 - Carbon dioxide and clean agent alarms.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 4 2014-10-01 2014-10-01 false Carbon dioxide and clean agent alarms. 131.815 Section 131.815 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OFFSHORE SUPPLY VESSELS OPERATIONS Markings for Fire Equipment and Emergency Equipment § 131.815 Carbon dioxide and clean agent alarms. Each carbon dioxide or clean agent fire...

  10. 46 CFR 131.815 - Carbon dioxide and clean agent alarms.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 4 2012-10-01 2012-10-01 false Carbon dioxide and clean agent alarms. 131.815 Section 131.815 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OFFSHORE SUPPLY VESSELS OPERATIONS Markings for Fire Equipment and Emergency Equipment § 131.815 Carbon dioxide and clean agent alarms. Each carbon dioxide or clean agent fire...

  11. 46 CFR 131.815 - Carbon dioxide and clean agent alarms.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 4 2013-10-01 2013-10-01 false Carbon dioxide and clean agent alarms. 131.815 Section 131.815 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OFFSHORE SUPPLY VESSELS OPERATIONS Markings for Fire Equipment and Emergency Equipment § 131.815 Carbon dioxide and clean agent alarms. Each carbon dioxide or clean agent fire...

  12. 46 CFR 108.627 - Carbon dioxide and clean agent alarms.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 4 2013-10-01 2013-10-01 false Carbon dioxide and clean agent alarms. 108.627 Section 108.627 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) A-MOBILE OFFSHORE DRILLING UNITS DESIGN AND EQUIPMENT Equipment Markings and Instructions § 108.627 Carbon dioxide and clean agent alarms. Each carbon dioxide alarm must be...

  13. Carbon dioxide absorbent and method of using the same

    DOEpatents

    Perry, Robert James; O'Brien, Michael Joseph

    2015-12-29

    In accordance with one aspect, the present invention provides a composition which contains the amino-siloxane structures I, or III, as described herein. The composition is useful for the capture of carbon dioxide from process streams. In addition, the present invention provides methods of preparing the amino-siloxane composition. Another aspect of the present invention provides methods for reducing the amount of carbon dioxide in a process stream employing the amino-siloxane compositions of the invention, as species which react with carbon dioxide to form an adduct with carbon dioxide.

  14. Carbon dioxide absorbent and method of using the same

    DOEpatents

    Perry, Robert James; O'Brien, Michael Joseph

    2014-06-10

    In accordance with one aspect, the present invention provides a composition which contains the amino-siloxane structures I, or III, as described herein. The composition is useful for the capture of carbon dioxide from process streams. In addition, the present invention provides methods of preparing the amino-siloxane composition. Another aspect of the present invention provides methods for reducing the amount of carbon dioxide in a process stream employing the amino-siloxane compositions of the invention, as species which react with carbon dioxide to form an adduct with carbon dioxide.

  15. Carbon dioxide absorbent and method of using the same

    DOEpatents

    Perry, Robert James [Niskayuna, NY; Lewis, Larry Neil [Scotia, NY; O'Brien, Michael Joseph [Clifton Park, NY; Soloveichik, Grigorii Lev [Latham, NY; Kniajanski, Sergei [Clifton Park, NY; Lam, Tunchiao Hubert [Clifton Park, NY; Lee, Julia Lam [Niskayuna, NY; Rubinsztajn, Malgorzata Iwona [Ballston Spa, NY

    2011-10-04

    In accordance with one aspect, the present invention provides an amino-siloxane composition comprising at least one of structures I, II, III, IV or V said compositions being useful for the capture of carbon dioxide from gas streams such as power plant flue gases. In addition, the present invention provides methods of preparing the amino-siloxane compositions are provided. Also provided are methods for reducing the amount of carbon dioxide in a process stream employing the amino-siloxane compositions of the invention as species which react with carbon dioxide to form an adduct with carbon dioxide. The reaction of the amino-siloxane compositions provided by the present invention with carbon dioxide is reversible and thus, the method provides for multicycle use of said compositions.

  16. Novel Technique and Technologies for Active Optical Remote Sensing of Greenhouse Gases

    NASA Technical Reports Server (NTRS)

    Singh, Upendra N.; Refaat, Tamer F.; Petros, Mulugeta

    2017-01-01

    The societal benefits of understanding climate change through identification of global carbon dioxide sources and sinks led to the desired NASA's active sensing of carbon dioxide emissions over nights, days, and seasons (ASCENDS) space-based missions of global carbon dioxide measurements. For more than 15 years, NASA Langley Research Center (LaRC) have developed several carbon dioxide active remote sensors using the differential absorption lidar (DIAL) technique operating at the two-micron wavelength. Currently, an airborne two-micron triple-pulse integrated path differential absorption (IPDA) lidar is under development. This IPDA lidar measures carbon dioxide as well as water vapor, the dominant interfering molecule on carbon dioxide remote sensing. Advancement of this triple-pulse IPDA lidar development is presented.

  17. Supercritical Carbon Dioxide Extraction of Bioactive Compounds from Ampelopsis grossedentata Stems: Process Optimization and Antioxidant Activity

    PubMed Central

    Wang, Yuefei; Ying, Le; Sun, Da; Zhang, Shikang; Zhu, Yuejin; Xu, Ping

    2011-01-01

    Supercritical carbon dioxide (SC-CO2) extraction of bioactive compounds including flavonoids and phenolics from Ampelopsis grossedentata stems was carried out. Extraction parameters such as pressure, temperature, dynamic time and modifier, were optimized using an orthogonal array design of L9 (34), and antioxidant activities of the extracts were evaluated by 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical scavenging assay and ferrous ion chelating (FIC) assay. The best conditions obtained for SC-CO2 extraction of flavonoids was 250 bar, 40 °C, 50 min, and with a modifier of methanol/ethanol (1:3, v/v), and that for phenolics extraction was 250 bar, 40 °C, 50 min, and with a modifier of methanol/ethanol (1:1, v/v). Meantime, flavonoids and phenolics were found to be mainly responsible for the DPPH scavenging activity of the extracts, but not for the chelating activity on ferrous ion according to Pearson correlation analysis. Furthermore, several unreported flavonoids such as apigenin, vitexin, luteolin, etc., have been detected in the extracts from A. grossedentata stems. PMID:22072923

  18. [Research of the essential oil of Plumeria rubra var. actifolia from Laos by supercritical carbon dioxide extraction].

    PubMed

    Xiao, Xin-Yu; Cui, Long-Hai; Zhou, Xin-Xin; Wu, Yan; Ge, Fa-Huan

    2011-05-01

    The orthogonal test and the supercritical carbon dioxide fluid extraction were used for optimizing the extraction of the essential oil from Plumeria rubra var. actifolia for the first time. Compared with the steam distillation, the optimal operation parameter of extraction was as follows: extraction pressure 25 MPa, extraction temperature 45 degrees C; separator I pressure 12 MPa, separator I temperature 55 degrees C; separator II pressure 6 MPa, separator II temperature 30 degrees C. Under this condition the yield of the essential oil was 5.8927%. The components were separated and identified by GC-MS. 53 components of Plumeria rubra var. actifolia measured by SFE method were identified and determined by normalization method. The main components were 1, 6, 10-dodecatrien-3-ol, 3, 7, 11-trimethyl, benzoic acid, 2-hydroxy-, phenylmethyl ester, 1, 2-benzenedicarboxylic acid, bis(2-methylpropyl) ester,etc.. 1, 2-Benzenedicarboxylic acid, bis (2-methylpropyl) este. took up 66.11% of the total amount, and there was much difference of the results from SD method.

  19. Carbon sequestration in depleted oil shale deposits

    DOEpatents

    Burnham, Alan K; Carroll, Susan A

    2014-12-02

    A method and apparatus are described for sequestering carbon dioxide underground by mineralizing the carbon dioxide with coinjected fluids and minerals remaining from the extraction shale oil. In one embodiment, the oil shale of an illite-rich oil shale is heated to pyrolyze the shale underground, and carbon dioxide is provided to the remaining depleted oil shale while at an elevated temperature. Conditions are sufficient to mineralize the carbon dioxide.

  20. Forecasting carbon dioxide emissions based on a hybrid of mixed data sampling regression model and back propagation neural network in the USA.

    PubMed

    Zhao, Xin; Han, Meng; Ding, Lili; Calin, Adrian Cantemir

    2018-01-01

    The accurate forecast of carbon dioxide emissions is critical for policy makers to take proper measures to establish a low carbon society. This paper discusses a hybrid of the mixed data sampling (MIDAS) regression model and BP (back propagation) neural network (MIDAS-BP model) to forecast carbon dioxide emissions. Such analysis uses mixed frequency data to study the effects of quarterly economic growth on annual carbon dioxide emissions. The forecasting ability of MIDAS-BP is remarkably better than MIDAS, ordinary least square (OLS), polynomial distributed lags (PDL), autoregressive distributed lags (ADL), and auto-regressive moving average (ARMA) models. The MIDAS-BP model is suitable for forecasting carbon dioxide emissions for both the short and longer term. This research is expected to influence the methodology for forecasting carbon dioxide emissions by improving the forecast accuracy. Empirical results show that economic growth has both negative and positive effects on carbon dioxide emissions that last 15 quarters. Carbon dioxide emissions are also affected by their own change within 3 years. Therefore, there is a need for policy makers to explore an alternative way to develop the economy, especially applying new energy policies to establish a low carbon society.

  1. Carbon-14 analyses reveal fine structure of the urban carbon dioxide dome in the Salt Lake Valley, Utah, USA

    NASA Astrophysics Data System (ADS)

    Ehleringer, J. R.; Hopkins, F. M.; Xu, X.; Barnette, J.; Randerson, J. T.; Bush, S.; Lai, C.

    2013-12-01

    Carbon-14 analyses of mature deciduous tree leaves (aspen and cottonwood) were used to measure the increases in atmospheric carbon dioxide within the expansive urbanizing Salt Lake Valley, Utah, USA associated with fossil fuel combustion. Our objectives were twofold: to understand the fine scale spatial structure of elevated carbon dioxide levels in this urban environment and to relate these observations to actual carbon dioxide observations collected using both long-term monitoring sites and a mobile measurement vehicle. Paired observations of aspen and cottonwood at sites across the valley showed that there was no significant difference in carbon-14 values, allowing spatial pattern evaluations at sites where one but not the other species was present. Statistically significant patterns were observed over a two-year measurement period, with elevated carbon dioxide levels associated with carbon-14 depleted leaves, particularly in regions with higher vehicle travel. Carbon-14 content of leaves was significantly lower on 4-lane roads than on nearby 2-lane roads in both residential and commercial zones, consistent with atmospheric carbon dioxide observations. The analysis of spatial patterns in the carbon-14 in leaves was then used to evaluate how well these observations compared to instantaneous and long-term observations of carbon dioxide using traditional infrared gas analyzer approaches.

  2. Carbon ion pump for removal of carbon dioxide from combustion gas and other gas mixtures

    DOEpatents

    Aines, Roger D.; Bourcier, William L.

    2014-08-19

    A novel method and system of separating carbon dioxide from flue gas is introduced. Instead of relying on large temperature or pressure changes to remove carbon dioxide from a solvent used to absorb it from flue gas, the ion pump method, as disclosed herein, dramatically increases the concentration of dissolved carbonate ion in solution. This increases the overlying vapor pressure of carbon dioxide gas, permitting carbon dioxide to be removed from the downstream side of the ion pump as a pure gas. The ion pumping may be obtained from reverse osmosis, electrodialysis, thermal desalination methods, or an ion pump system having an oscillating flow in synchronization with an induced electric field.

  3. Carbon ion pump for removal of carbon dioxide from combustion gas and other gas mixtures

    DOEpatents

    Aines, Roger D.; Bourcier, William L.

    2010-11-09

    A novel method and system of separating carbon dioxide from flue gas is introduced. Instead of relying on large temperature or pressure changes to remove carbon dioxide from a solvent used to absorb it from flue gas, the ion pump method, as disclosed herein, dramatically increases the concentration of dissolved carbonate ion in solution. This increases the overlying vapor pressure of carbon dioxide gas, permitting carbon dioxide to be removed from the downstream side of the ion pump as a pure gas. The ion pumping may be obtained from reverse osmosis, electrodialysis, thermal desalination methods, or an ion pump system having an oscillating flow in synchronization with an induced electric field.

  4. Hydrodynamic Controls on Carbon Dioxide Efflux from Inland Waters

    NASA Astrophysics Data System (ADS)

    Long, H. E.; Waldron, S.; Hoey, T.; Newton, J.; Quemin, S.

    2013-12-01

    Intensive research has been undertaken on carbon dioxide efflux from lakes, estuaries and oceans, but much less attention has been given to rivers and streams, especially lower order streams. River systems are often over-saturated with carbon dioxide and so tend to act as sources of carbon dioxide to the atmosphere. It has been thought that rivers act as pipes carrying this terrestrial carbon to the oceans. However, recent studies have shown that a significant amount of the carbon is reprocessed within the system in a series of transformations and losses. Fluvial evasion of carbon dioxide is now recognised to be a significant component of carbon cycles, however the factors controlling carbon dioxide efflux and its magnitude remain poorly understood and quantified. This research aims to quantify, and better understand the controls on, freshwater carbon dioxide evasion. Data are presented here from field measurements that commenced in Sept 2013 in two contrasting Scottish rivers: the River Kelvin which has a large (335 km.sq) part-urban catchment with predominantly non-peat soils and Drumtee Water, a small (9.6 km.sq) rural catchment of peat soils and agricultural land. Using a floating chamber with the headspace connected to an infrared gas analyser to measure changes in carbon dioxide concentration, efflux rates from 0.22 - 47.4 μmol CO2/m.sq/sec were measured, these close to the middle of the range of previously reported values. At one site on the River Kelvin in May 2013 an influx of -0.61 - -3.53 μmol CO2/m.sq/sec was recorded. Whereas previous research finds carbon dioxide efflux to increase with decreasing river size and a more organic-rich soil catchment, here the controls on carbon dioxide evasion are similar across the contrasting catchments. Carbon dioxide evasion shows seasonality, with maximum fluxes in the summer months being up to twice as high as the winter maxima. Linear regression demonstrates that evasion increases with increased flow velocity, water surface disturbance indicated by Froude number, and turbulent mixing indicated by Reynolds number. Similar relationships with season, flow velocity and turbulence have been reported previously, but there is little known about the mechanisms involved. When comparing spot carbon dioxide efflux measurements to river stage time series data, carbon dioxide efflux is more sensitive to an increase in stage at more turbulent measurement points. Further investigation of the mechanisms will be obtained by measurement of DIC concentration and isotopic composition to assess the controls of carbon source versus degassing, and the analysis of the interactions between hydraulic and seasonal controls and carbon dioxide fluxes extended.

  5. Solubility of Carbon Dioxide in Water.

    ERIC Educational Resources Information Center

    Bush, Pat; And Others

    1992-01-01

    Describes an activity measuring the amount of dissolved carbon dioxide in carbonated water at different temperatures. The amount of carbon dioxide is measured by the amount of dilute ammonia solution needed to produce a pH indicator color change. (PR)

  6. Numerically Simulating Carbonate Mineralization of Basalt with Injection of Carbon Dioxide into Deep Saline Formations

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    White, Mark D.; McGrail, B. Peter; Schaef, Herbert T.

    2006-07-08

    The principal mechanisms for the geologic sequestration of carbon dioxide in deep saline formations include geological structural trapping, hydrological entrapment of nonwetting fluids, aqueous phase dissolution and ionization, and geochemical sorption and mineralization. In sedimentary saline formations the dominant mechanisms are structural and dissolution trapping, with moderate to weak contributions from hydrological and geochemical trapping; where, hydrological trapping occurs during the imbibition of aqueous solution into pore spaces occupied by gaseous carbon dioxide, and geochemical trapping is controlled by generally slow reaction kinetics. In addition to being globally abundant and vast, deep basaltic lava formations offer mineralization kinetics that makemore » geochemical trapping a dominate mechanism for trapping carbon dioxide in these formations. For several decades the United States Department of Energy has been investigating Columbia River basalt in the Pacific Northwest as part of its environmental programs and options for natural gas storage. Recently this nonpotable and extensively characterized basalt formation is being reconsidered as a potential reservoir for geologic sequestration of carbon dioxide. The reservoir has an estimated storage capacity of 100 giga tonnes of carbon dioxide and comprises layered basalt flows with sublayering that generally alternates between low permeability massive and high permeability breccia. Chemical analysis of the formation shows 10 wt% Fe, primarily in the +2 valence. The mineralization reaction that makes basalt formations attractive for carbon dioxide sequestration is that of calcium, magnesium, and iron silicates reacting with dissolved carbon dioxide, producing carbonate minerals and amorphous quartz. Preliminary estimates of the kinetics of the silicate-to-carbonate reactions have been determined experimentally and this research is continuing to determine effects of temperature, pressure, rock composition and mineral assemblages on the reaction rates. This study numerically investigates the injection, migration and sequestration of supercritical carbon dioxide in deep Columbia River basalt formations using the multifluid subsurface flow and reactive transport simulator STOMP-CO2 with its ECKEChem module. Simulations are executed on high resolution multiple stochastic realizations of the layered basalt systems and demonstrate the migration behavior through layered basalt formations and the mineralization of dissolved carbon dioxide. Reported results include images of the migration behavior, distribution of carbonate formation, quantities of injected and sequestered carbon dioxide, and percentages of the carbon dioxide sequestered by different mechanisms over time.« less

  7. Carbon dioxide emissions, GDP, energy use, and population growth: a multivariate and causality analysis for Ghana, 1971-2013.

    PubMed

    Asumadu-Sarkodie, Samuel; Owusu, Phebe Asantewaa

    2016-07-01

    In this study, the relationship between carbon dioxide emissions, GDP, energy use, and population growth in Ghana was investigated from 1971 to 2013 by comparing the vector error correction model (VECM) and the autoregressive distributed lag (ARDL). Prior to testing for Granger causality based on VECM, the study tested for unit roots, Johansen's multivariate co-integration and performed a variance decomposition analysis using Cholesky's technique. Evidence from the variance decomposition shows that 21 % of future shocks in carbon dioxide emissions are due to fluctuations in energy use, 8 % of future shocks are due to fluctuations in GDP, and 6 % of future shocks are due to fluctuations in population. There was evidence of bidirectional causality running from energy use to GDP and a unidirectional causality running from carbon dioxide emissions to energy use, carbon dioxide emissions to GDP, carbon dioxide emissions to population, and population to energy use. Evidence from the long-run elasticities shows that a 1 % increase in population in Ghana will increase carbon dioxide emissions by 1.72 %. There was evidence of short-run equilibrium relationship running from energy use to carbon dioxide emissions and GDP to carbon dioxide emissions. As a policy implication, the addition of renewable energy and clean energy technologies into Ghana's energy mix can help mitigate climate change and its impact in the future.

  8. 46 CFR 35.40-10 - Steam, foam, carbon dioxide, or clean agent fire smothering apparatus-TB/ALL.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 1 2013-10-01 2013-10-01 false Steam, foam, carbon dioxide, or clean agent fire... TANK VESSELS OPERATIONS Posting and Marking Requirements-TB/ALL § 35.40-10 Steam, foam, carbon dioxide, or clean agent fire smothering apparatus—TB/ALL. Each steam, foam, carbon dioxide, or clean agent...

  9. 46 CFR 35.40-10 - Steam, foam, carbon dioxide, or clean agent fire smothering apparatus-TB/ALL.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 1 2014-10-01 2014-10-01 false Steam, foam, carbon dioxide, or clean agent fire... TANK VESSELS OPERATIONS Posting and Marking Requirements-TB/ALL § 35.40-10 Steam, foam, carbon dioxide, or clean agent fire smothering apparatus—TB/ALL. Each steam, foam, carbon dioxide, or clean agent...

  10. 46 CFR 97.37-9 - Carbon dioxide and clean agent alarms.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 4 2014-10-01 2014-10-01 false Carbon dioxide and clean agent alarms. 97.37-9 Section 97.37-9 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) CARGO AND MISCELLANEOUS VESSELS OPERATIONS Markings for Fire and Emergency Equipment, Etc. § 97.37-9 Carbon dioxide and clean agent alarms. Each carbon dioxide or clean agent...

  11. 46 CFR 78.47-9 - Carbon dioxide and clean agent alarms.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 3 2013-10-01 2013-10-01 false Carbon dioxide and clean agent alarms. 78.47-9 Section 78.47-9 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) PASSENGER VESSELS OPERATIONS Markings for Fire and Emergency Equipment, Etc. § 78.47-9 Carbon dioxide and clean agent alarms. Each carbon dioxide or clean agent fire...

  12. 46 CFR 78.47-9 - Carbon dioxide and clean agent alarms.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 3 2012-10-01 2012-10-01 false Carbon dioxide and clean agent alarms. 78.47-9 Section 78.47-9 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) PASSENGER VESSELS OPERATIONS Markings for Fire and Emergency Equipment, Etc. § 78.47-9 Carbon dioxide and clean agent alarms. Each carbon dioxide or clean agent fire...

  13. TES/Aura L2 Carbon Dioxide (CO2) Nadir V6 (TL2CO2N)

    Atmospheric Science Data Center

    2018-01-18

    TES/Aura L2 Carbon Dioxide (CO2) Nadir (TL2CO2N) News:  TES News ... Level:  L2 Platform:  TES/Aura L2 Carbon Dioxide Spatial Coverage:  5.2 x 8.5 km nadir ... Contact User Services Parameters:  Carbon Dioxide Legacy:  Retired data product , click here ...

  14. 46 CFR 97.37-9 - Carbon dioxide and clean agent alarms.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 4 2013-10-01 2013-10-01 false Carbon dioxide and clean agent alarms. 97.37-9 Section 97.37-9 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) CARGO AND MISCELLANEOUS VESSELS OPERATIONS Markings for Fire and Emergency Equipment, Etc. § 97.37-9 Carbon dioxide and clean agent alarms. Each carbon dioxide or clean agent...

  15. 46 CFR 34.15-20 - Carbon dioxide storage-T/ALL.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 1 2012-10-01 2012-10-01 false Carbon dioxide storage-T/ALL. 34.15-20 Section 34.15-20 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY TANK VESSELS FIREFIGHTING EQUIPMENT Carbon Dioxide Extinguishing Systems, Details § 34.15-20 Carbon dioxide storage—T/ALL. (a) Except as provided in paragraph (b) of this section, the cylinders...

  16. 46 CFR 97.37-9 - Carbon dioxide and clean agent alarms.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 4 2012-10-01 2012-10-01 false Carbon dioxide and clean agent alarms. 97.37-9 Section 97.37-9 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) CARGO AND MISCELLANEOUS VESSELS OPERATIONS Markings for Fire and Emergency Equipment, Etc. § 97.37-9 Carbon dioxide and clean agent alarms. Each carbon dioxide or clean agent...

  17. 46 CFR 78.47-9 - Carbon dioxide and clean agent alarms.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 3 2014-10-01 2014-10-01 false Carbon dioxide and clean agent alarms. 78.47-9 Section 78.47-9 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) PASSENGER VESSELS OPERATIONS Markings for Fire and Emergency Equipment, Etc. § 78.47-9 Carbon dioxide and clean agent alarms. Each carbon dioxide or clean agent fire...

  18. TES/Aura L2 Carbon Dioxide (CO2) Nadir V6 (TL2CO2NS)

    Atmospheric Science Data Center

    2018-01-22

    TES/Aura L2 Carbon Dioxide (CO2) Nadir (TL2CO2NS) News:  TES News ... Level:  L2 Platform:  TES/Aura L2 Carbon Dioxide Spatial Coverage:  5.3 x 8.5 km nadir ... Contact ASDC User Services Parameters:  Carbon Dioxide Legacy:  Retired data product , click here ...

  19. 40 CFR 60.1745 - What must I do if I choose to monitor carbon dioxide instead of oxygen as a diluent gas?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... carbon dioxide instead of oxygen as a diluent gas? 60.1745 Section 60.1745 Protection of Environment... choose to monitor carbon dioxide instead of oxygen as a diluent gas? You must establish the relationship between oxygen and carbon dioxide during the initial evaluation of your continuous emission monitoring...

  20. 40 CFR 60.1745 - What must I do if I choose to monitor carbon dioxide instead of oxygen as a diluent gas?

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... carbon dioxide instead of oxygen as a diluent gas? 60.1745 Section 60.1745 Protection of Environment... choose to monitor carbon dioxide instead of oxygen as a diluent gas? You must establish the relationship between oxygen and carbon dioxide during the initial evaluation of your continuous emission monitoring...

  1. 40 CFR 60.1745 - What must I do if I choose to monitor carbon dioxide instead of oxygen as a diluent gas?

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... carbon dioxide instead of oxygen as a diluent gas? 60.1745 Section 60.1745 Protection of Environment... choose to monitor carbon dioxide instead of oxygen as a diluent gas? You must establish the relationship between oxygen and carbon dioxide during the initial evaluation of your continuous emission monitoring...

  2. 40 CFR 60.1745 - What must I do if I choose to monitor carbon dioxide instead of oxygen as a diluent gas?

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... carbon dioxide instead of oxygen as a diluent gas? 60.1745 Section 60.1745 Protection of Environment... choose to monitor carbon dioxide instead of oxygen as a diluent gas? You must establish the relationship between oxygen and carbon dioxide during the initial evaluation of your continuous emission monitoring...

  3. 40 CFR 60.1745 - What must I do if I choose to monitor carbon dioxide instead of oxygen as a diluent gas?

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... carbon dioxide instead of oxygen as a diluent gas? 60.1745 Section 60.1745 Protection of Environment... choose to monitor carbon dioxide instead of oxygen as a diluent gas? You must establish the relationship between oxygen and carbon dioxide during the initial evaluation of your continuous emission monitoring...

  4. The carbon dioxide cycle

    USGS Publications Warehouse

    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.

  5. The impact of energy, agriculture, macroeconomic and human-induced indicators on environmental pollution: evidence from Ghana.

    PubMed

    Asumadu-Sarkodie, Samuel; Owusu, Phebe Asantewaa

    2017-03-01

    In this study, the impact of energy, agriculture, macroeconomic and human-induced indicators on environmental pollution from 1971 to 2011 is investigated using the statistically inspired modification of partial least squares (SIMPLS) regression model. There was evidence of a linear relationship between energy, agriculture, macroeconomic and human-induced indicators and carbon dioxide emissions. Evidence from the SIMPLS regression shows that a 1% increase in crop production index will reduce carbon dioxide emissions by 0.71%. Economic growth increased by 1% will reduce carbon dioxide emissions by 0.46%, which means that an increase in Ghana's economic growth may lead to a reduction in environmental pollution. The increase in electricity production from hydroelectric sources by 1% will reduce carbon dioxide emissions by 0.30%; thus, increasing renewable energy sources in Ghana's energy portfolio will help mitigate carbon dioxide emissions. Increasing enteric emissions by 1% will increase carbon dioxide emissions by 4.22%, and a 1% increase in the nitrogen content of manure management will increase carbon dioxide emissions by 6.69%. The SIMPLS regression forecasting exhibited a 5% MAPE from the prediction of carbon dioxide emissions.

  6. Carbon dioxide sensor

    DOEpatents

    Dutta, Prabir K [Worthington, OH; Lee, Inhee [Columbus, OH; Akbar, Sheikh A [Hilliard, OH

    2011-11-15

    The present invention generally relates to carbon dioxide (CO.sub.2) sensors. In one embodiment, the present invention relates to a carbon dioxide (CO.sub.2) sensor that incorporates lithium phosphate (Li.sub.3PO.sub.4) as an electrolyte and sensing electrode comprising a combination of lithium carbonate (Li.sub.2CO.sub.3) and barium carbonate (BaCO.sub.3). In another embodiment, the present invention relates to a carbon dioxide (CO.sub.2) sensor has a reduced sensitivity to humidity due to a sensing electrode with a layered structure of lithium carbonate and barium carbonate. In still another embodiment, the present invention relates to a method of producing carbon dioxide (CO.sub.2) sensors having lithium phosphate (Li.sub.3PO.sub.4) as an electrolyte and sensing electrode comprising a combination of lithium carbonate (Li.sub.2CO.sub.3) and barium carbonate (BaCO.sub.3).

  7. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Waldhoff, Stephanie T.; Anthoff, David; Rose, Steven K.

    We use FUND 3.8 to estimate the social cost of four greenhouse gases: carbon dioxide, methane, nitrous oxide, and sulphur hexafluoride emissions. The damage potential for each gas—the ratio of the social cost of the non-carbon dioxide greenhouse gas to the social cost of carbon dioxide—is also estimated. The damage potentials are compared to several metrics, focusing in particular on the global warming potentials, which are frequently used to measure the trade-off between gases in the form of carbon dioxide equivalents. We find that damage potentials could be significantly higher than global warming potentials. This finding implies that previous papersmore » have underestimated the relative importance of reducing non-carbon dioxide greenhouse gas emissions from an economic damage perspective. We show results for a range of sensitivity analyses: carbon dioxide fertilization on agriculture productivity, terrestrial feedbacks, climate sensitivity, discounting, equity weighting, and socioeconomic and emissions scenarios. The sensitivity of the results to carbon dioxide fertilization is a primary focus as it is an important element of climate change that has not been considered in much of the previous literature. We estimate that carbon dioxide fertilization has a large positive impact that reduces the social cost of carbon dioxide with a much smaller effect on the other greenhouse gases. As a result, our estimates of the damage potentials of methane and nitrous oxide are much higher compared to estimates that ignore carbon dioxide fertilization. As a result, our base estimates of the damage potential for methane and nitrous oxide that include carbon dioxide fertilization are twice their respective global warming potentials. Our base estimate of the damage potential of sulphur hexafluoride is similar to the one previous estimate, both almost three times the global warming potential.« less

  8. High resolution spectroscopic measurements of carbon dioxide and carbon monoxide

    NASA Technical Reports Server (NTRS)

    Chaney, L. W.

    1972-01-01

    A modified 1.83 meter Jarrell-Ash spectrometer is reported. The instrument was double passed and achieved a resolution of 0.05 cm at 15 micrometers. An integrating voltmeter was used to optimize the available integration time. Data were obtained in the 15 micrometer and 4.3 micrometer band of CO2 and the 4.6 micrometer and 2.3 micrometer bands of CO. The data are summarized and examples of typical spectra are given. All the data are stored on IBM cards.

  9. Experimental measurement and thermodynamic modeling of the solubility of carbon dioxide in aqueous blends of monoethanolamine and diethanolamine

    NASA Astrophysics Data System (ADS)

    Suleman, Humbul; Maulud, Abdulhalim Shah; Man, Zakaria

    2017-12-01

    In this study, the solubilities of carbon dioxide in aqueous mixtures of monoethanolamine (MEA) and diethanolamine (DEA) were determined using a high pressure vapor-liquid equilibrium apparatus. The carbon dioxide loadings (mole of CO2/mole of amine mixture) were reported for a wide range of temperature (303.15, 323.15, 343.15 K) and pressure (100 - 4100 kPa). The carbon dioxide solubility shows an increase with increase in pressure and amine concentration and a decrease with increase in temperature in the aqueous blends of MEA and DEA. At carbon dioxide loadings above 1.0, the carbon dioxide solubility becomes a weak function of pressure and follows the general trend of carbon dioxide solubility in aqueous alkanolamines. The new experimental data points determined in this study were correlated by using a recently developed, enhanced Kent-Eisenberg model. An average absolute relative error of 9.4 % was observed between the model results and experimental data, indicating good correlative capability of the thermodynamic model.

  10. Apparatus and method for removing solvent from carbon dioxide in resin recycling system

    DOEpatents

    Bohnert, George W [Harrisonville, MO; Hand, Thomas E [Lee's Summit, MO; DeLaurentiis, Gary M [Jamestown, CA

    2009-01-06

    A two-step resin recycling system and method solvent that produces essentially contaminant-free synthetic resin material. The system and method includes one or more solvent wash vessels to expose resin particles to a solvent, the solvent contacting the resin particles in the one or more solvent wash vessels to substantially remove contaminants on the resin particles. A separator is provided to separate the solvent from the resin particles after removal from the one or more solvent wash vessels. The resin particles are next exposed to carbon dioxide in a closed loop carbon dioxide system. The closed loop system includes a carbon dioxide vessel where the carbon dioxide is exposed to the resin, substantially removing any residual solvent remaining on the resin particles after separation. A separation vessel is also provided to separate the solvent from the solvent laden carbon dioxide. Both the carbon dioxide and the solvent are reused after separation in the separation vessel.

  11. Epoxide-functionalization of polyethyleneimine for synthesis of stable carbon dioxide adsorbent in temperature swing adsorption

    PubMed Central

    Choi, Woosung; Min, Kyungmin; Kim, Chaehoon; Ko, Young Soo; Jeon, Jae Wan; Seo, Hwimin; Park, Yong-Ki; Choi, Minkee

    2016-01-01

    Amine-containing adsorbents have been extensively investigated for post-combustion carbon dioxide capture due to their ability to chemisorb low-concentration carbon dioxide from a wet flue gas. However, earlier studies have focused primarily on the carbon dioxide uptake of adsorbents, and have not demonstrated effective adsorbent regeneration and long-term stability under such conditions. Here, we report the versatile and scalable synthesis of a functionalized-polyethyleneimine (PEI)/silica adsorbent which simultaneously exhibits a large working capacity (2.2 mmol g−1) and long-term stability in a practical temperature swing adsorption process (regeneration under 100% carbon dioxide at 120 °C), enabling the separation of concentrated carbon dioxide. We demonstrate that the functionalization of PEI with 1,2-epoxybutane reduces the heat of adsorption and facilitates carbon dioxide desorption (>99%) during regeneration compared with unmodified PEI (76%). Moreover, the functionalization significantly improves long-term adsorbent stability over repeated temperature swing adsorption cycles due to the suppression of urea formation and oxidative amine degradation. PMID:27572662

  12. The Impact of Carbon Dioxide on Climate.

    ERIC Educational Resources Information Center

    MacDonald, Gordon J.

    1979-01-01

    Examines the relationship between climatic change and carbon dioxide from the historical perspective; details the contributions of carbon-based fuels to increasing carbon dioxide concentrations; and using global circulation models, discusses the future impact of the heavy reliance of our society on carbon-based fuels on climatic change. (BT)

  13. Fixation of carbon dioxide into dimethyl carbonate over titanium-based zeolitic thiophene-benzimidazolate framework

    EPA Science Inventory

    A titanium-based zeolitic thiophene-benzimidazolate framework has been designed for the direct synthesis of dimethyl carbonate (DMC) from methanol and carbon dioxide. The developed catalyst activates carbon dioxide and delivers over 16% yield of DMC without the use of any dehydra...

  14. Self-Cleaning Boudouard Reactor for Full Oxygen Recovery from Carbon Dioxide

    NASA Technical Reports Server (NTRS)

    Coutts, Janelle; Hintze, Paul E.; Muscatello, Anthony C.; Gibson, Tracy L.; Captain, James G.; Lunn, Griffin M.; Devor, Robert W.; Bauer, Brint; Parks, Steve

    2016-01-01

    Oxygen recovery from respiratory carbon dioxide is an important aspect of human spaceflight. Methods exist to sequester the carbon dioxide, but production of oxygen needs further development. The current International Space Station Carbon Dioxide Reduction System (CRS) uses the Sabatier reaction to produce water (and ultimately breathing air). Oxygen recovery is limited to 50 because half of the hydrogen used in the Sabatier reactor is lost as methane, which is vented overboard. The Bosch reaction, which converts carbon dioxide to oxygen and solid carbon is capable of recovering all the oxygen from carbon dioxide, and is the only real alternative to the Sabatier reaction. However, the last reaction in the cycle, the Boudouard reaction, produces solid carbon and the resulting carbon buildup will eventually foul the nickel or iron catalyst, reducing reactor life and increasing consumables. To minimize this fouling and increase efficiency, a number of self-cleaning catalyst designs have been created. This paper will describe recent results evaluating one of the designs.

  15. Self-Cleaning Boudouard Reactor for Full Oxygen Recovery from Carbon Dioxide

    NASA Technical Reports Server (NTRS)

    Hintze, Paul E.; Muscatello, Anthony C.; Meier, Anne J.; Gibson, Tracy L.; Captain, James G.; Lunn, Griffin M.; Devor, Robert W.

    2016-01-01

    Oxygen recovery from respiratory carbon dioxide is an important aspect of human spaceflight. Methods exist to sequester the carbon dioxide, but production of oxygen needs further development. The current International Space Station Carbon Dioxide Reduction System (CRS) uses the Sabatier reaction to produce water (and ultimately breathing air). Oxygen recovery is limited to 50% because half of the hydrogen used in the Sabatier reactor is lost as methane, which is vented overboard. The Bosch reaction, which converts carbon dioxide to oxygen and solid carbon is capable of recovering all the oxygen from carbon dioxide, and is the only real alternative to the Sabatier reaction. However, the last reaction in the cycle, the Boudouard reaction, produces solid carbon and the resulting carbon buildup will eventually foul the nickel or iron catalyst, reducing reactor life and increasing consumables. To minimize this fouling and increase efficiency, a number of self-cleaning catalyst designs have been created. This paper will describe recent results evaluating one of the designs.

  16. Self-Cleaning Boudouard Reactor for Full Oxygen Recovery from Carbon Dioxide

    NASA Technical Reports Server (NTRS)

    Hintze, Paul E.; Muscatello, Anthony C.; Gibson, Tracy L.; Captain, James G.; Lunn, Griffin M.; Devor, Robert W.; Bauer, Brint; Parks, Steve

    2016-01-01

    Oxygen recovery from respiratory carbon dioxide is an important aspect of human spaceflight. Methods exist to sequester the carbon dioxide, but production of oxygen needs further development. The current International Space Station Carbon Dioxide Reduction System (CRS) uses the Sabatier reaction to produce water (and ultimately breathing air). Oxygen recovery is limited to 50% because half of the hydrogen used in the Sabatier reactor is lost as methane which is vented overboard. The Bosch reaction, which converts carbon dioxide to oxygen and solid carbon, is capable of recovering all the oxygen from carbon dioxide, and it is a promising alternative to the Sabatier reaction. However, the last reaction in the cycle, the Boudouard reaction, produces solid carbon, and the resulting carbon buildup eventually fouls the catalyst, reducing reactor life and increasing consumables. To minimize this fouling and increase efficiency, a number of self-cleaning catalyst designs have been created. This paper will describe recent results evaluating one of the designs.

  17. Primary discussion of a carbon sink in the oceans

    NASA Astrophysics Data System (ADS)

    Ma, Caihua; You, Kui; Ji, Dechun; Ma, Weiwei; Li, Fengqi

    2015-04-01

    As a consequence of global warming and rising sea levels, the oceans are becoming a matter of concern for more and more people because these changes will impact the growth of living organisms as well as people's living standards. In particular, it is extremely important that the oceans absorb massive amounts of carbon dioxide. This paper takes a pragmatic approach to analyzing the oceans with respect to the causes of discontinuities in oceanic variables of carbon dioxide sinks. We report on an application of chemical, physical and biological methods to analyze the changes of carbon dioxide in oceans. Based on the relationships among the oceans, land, atmosphere and sediment with respect to carbon dioxide, the foundation of carbon dioxide in shell-building and ocean acidification, the changes in carbon dioxide in the oceans and their impact on climate change, and so on, a vital conclusion can be drawn from this study. Specifically, under the condition that the oceans are not disturbed by external forces, the oceans are a large carbon dioxide sink. The result can also be inferred by the formula: C=A-B and G=E+F when the marine ecosystem can keep a natural balance and the amount of carbon dioxide emission is limited within the carrying capacity of the oceans.

  18. Optimization of artemisinin extraction from Artemisia annua L. with supercritical carbon dioxide + ethanol using response surface methodology.

    PubMed

    Ciftci, Ozan Nazim; Cahyadi, Jessica; Guigard, Selma E; Saldaña, Marleny D A

    2018-05-13

    Malaria is a high priority life-threatening public health concern in developing countries, and therefore there is a growing interest to obtain artemisinin for the production of artemisinin-based combination therapy products. In this study, artemisinin was extracted from the Artemisia annua L. plant using supercritical carbon dioxide (SC-CO 2 ) modified with ethanol. Response surface methodology based on central composite rotatable design was employed to investigate and optimize the extraction conditions of pressure (9.9-30 MPa), temperature (33-67°C), and co-solvent (ethanol, 0-12.6 wt.%). Optimum SC-CO 2 extraction conditions were found to be 30 MPa and 33°C without ethanol. Under optimized conditions, the predicted artemisinin yield was 1.09% whereas the experimental value was 0.71 ± 0.07%. Soxhlet extraction with hexane resulted in higher artemisinin yields and there was no significant difference in the purity of the extracts obtained with SC-CO 2 and Soxhlet extractions. Results indicated that SC-CO 2 and SC-CO 2 +ethanol extraction is a promising alternative for the extraction of artemisinin to eliminate the use of organic solvents, such as hexane, and produce extracts that can be used for the production of antimalarial products. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  19. Enhanced open ocean storage of CO2 from shelf sea pumping.

    PubMed

    Thomas, Helmuth; Bozec, Yann; Elkalay, Khalid; de Baar, Hein J W

    2004-05-14

    Seasonal field observations show that the North Sea, a Northern European shelf sea, is highly efficient in pumping carbon dioxide from the atmosphere to the North Atlantic Ocean. The bottom topography-controlled stratification separates production and respiration processes in the North Sea, causing a carbon dioxide increase in the subsurface layer that is ultimately exported to the North Atlantic Ocean. Globally extrapolated, the net uptake of carbon dioxide by coastal and marginal seas is about 20% of the world ocean's uptake of anthropogenic carbon dioxide, thus enhancing substantially the open ocean carbon dioxide storage.

  20. A hybrid absorption–adsorption method to efficiently capture carbon

    PubMed Central

    Liu, Huang; Liu, Bei; Lin, Li-Chiang; Chen, Guangjin; Wu, Yuqing; Wang, Jin; Gao, Xueteng; Lv, Yining; Pan, Yong; Zhang, Xiaoxin; Zhang, Xianren; Yang, Lanying; Sun, Changyu; Smit, Berend; Wang, Wenchuan

    2014-01-01

    Removal of carbon dioxide is an essential step in many energy-related processes. Here we report a novel slurry concept that combines specific advantages of metal-organic frameworks, ion liquids, amines and membranes by suspending zeolitic imidazolate framework-8 in glycol-2-methylimidazole solution. We show that this approach may give a more efficient technology to capture carbon dioxide compared to conventional technologies. The carbon dioxide sorption capacity of our slurry reaches 1.25 mol l−1 at 1 bar and the selectivity of carbon dioxide/hydrogen, carbon dioxide/nitrogen and carbon dioxide/methane achieves 951, 394 and 144, respectively. We demonstrate that the slurry can efficiently remove carbon dioxide from gas mixtures at normal pressure/temperature through breakthrough experiments. Most importantly, the sorption enthalpy is only −29 kJ mol−1, indicating that significantly less energy is required for sorbent regeneration. In addition, from a technological point of view, unlike solid adsorbents slurries can flow and be pumped. This allows us to use a continuous separation process with heat integration. PMID:25296559

  1. Thermochemical cyclic system for splitting water and/or carbon dioxide by means of cerium compounds and reactions useful therein

    DOEpatents

    Bamberger, C.E.; Robinson, P.R.

    A thermochemical cyclic process for producing hydrogen from water comprises reacting ceric oxide with monobasic or dibasic alkali metal phosphate to yield a solid reaction product, oxygen and water. The solid reaction product, alkali metal carbonate or bicarbonate, and water, are reacted to yield hydrogen, ceric oxide, carbon dioxide and trialkali metal phosphate. Ceric oxide is recycled. Trialkali metal phosphate, carbon dioxide and water are reacted to yield monobasic or dibasic alkali metal phosphate and alkali metal bicarbonate, which are recycled. The cyclic process can be modified for producing carbon monoxide from carbon dioxide by reacting the alkali metal cerous phosphate and alkali metal carbonate or bicarbonate in the absence of water to produce carbon monoxide, ceric oxide, carbon dioxide and trialkali metal phosphate. Carbon monoxide can be converted to hydrogen by the water gas shift reaction.

  2. Thermochemical cyclic system for splitting water and/or carbon dioxide by means of cerium compounds and reactions useful therein

    DOEpatents

    Bamberger, Carlos E.; Robinson, Paul R.

    1980-01-01

    A thermochemical cyclic process for producing hydrogen from water comprises reacting ceric oxide with monobasic or dibasic alkali metal phosphate to yield a solid reaction product, oxygen and water. The solid reaction product, alkali metal carbonate or bicarbonate, and water, are reacted to yield hydrogen, ceric oxide, carbon dioxide and trialkali metal phosphate. Ceric oxide is recycled. Trialkali metal phosphate, carbon dioxide and water are reacted to yield monobasic or dibasic alkali metal phosphate and alkali metal bicarbonate, which are recycled. The cylic process can be modified for producing carbon monoxide from carbon dioxide by reacting the alkali metal cerous phosphate and alkali metal carbonate or bicarbonate in the absence of water to produce carbon monoxide, ceric oxide, carbon dioxide and trialkali metal phosphate. Carbon monoxide can be converted to hydrogen by the water gas shift reaction.

  3. 46 CFR 76.15-1 - Application.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... Dioxide Extinguishing Systems, Details § 76.15-1 Application. (a) Where a carbon dioxide extinguishing... “high pressure system”, i.e., one in which the carbon dioxide is stored in liquid form at atmospheric temperature. Details for “low pressure systems”, i.e., those in which the carbon dioxide is stored in liquid...

  4. 46 CFR 76.15-1 - Application.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... Dioxide Extinguishing Systems, Details § 76.15-1 Application. (a) Where a carbon dioxide extinguishing... “high pressure system”, i.e., one in which the carbon dioxide is stored in liquid form at atmospheric temperature. Details for “low pressure systems”, i.e., those in which the carbon dioxide is stored in liquid...

  5. 46 CFR 76.15-1 - Application.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... Dioxide Extinguishing Systems, Details § 76.15-1 Application. (a) Where a carbon dioxide extinguishing... “high pressure system”, i.e., one in which the carbon dioxide is stored in liquid form at atmospheric temperature. Details for “low pressure systems”, i.e., those in which the carbon dioxide is stored in liquid...

  6. 46 CFR 76.15-1 - Application.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... Dioxide Extinguishing Systems, Details § 76.15-1 Application. (a) Where a carbon dioxide extinguishing... “high pressure system”, i.e., one in which the carbon dioxide is stored in liquid form at atmospheric temperature. Details for “low pressure systems”, i.e., those in which the carbon dioxide is stored in liquid...

  7. [Simplified identification and filter device of carbon dioxide].

    PubMed

    Mei, Xue-qin; Zhang, Yi-ping

    2009-11-01

    This paper presents the design and implementation ways of a simplified device to identify and filter carbon dioxide. The gas went through the test interface which had wet litmus paper before entering the abdominal cavity. Carbon dioxide dissolving in water turned acidic, making litmus paper change color to identify carbon dioxide, in order to avoid malpractice by connecting the wrong gas when making Endoscopic surgery.

  8. 46 CFR 35.40-7 - Carbon dioxide and clean agent alarms-T/ALL.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 1 2012-10-01 2012-10-01 false Carbon dioxide and clean agent alarms-T/ALL. 35.40-7 Section 35.40-7 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY TANK VESSELS OPERATIONS Posting and Marking Requirements-TB/ALL § 35.40-7 Carbon dioxide and clean agent alarms—T/ALL. Each carbon dioxide or clean agent fire extinguishing alarm...

  9. 40 CFR 62.15200 - What must I do if I choose to monitor carbon dioxide instead of oxygen as a diluent gas?

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... carbon dioxide instead of oxygen as a diluent gas? 62.15200 Section 62.15200 Protection of Environment... I do if I choose to monitor carbon dioxide instead of oxygen as a diluent gas? You must establish the relationship between oxygen and carbon dioxide during the initial evaluation of your continuous...

  10. 40 CFR 62.15200 - What must I do if I choose to monitor carbon dioxide instead of oxygen as a diluent gas?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... carbon dioxide instead of oxygen as a diluent gas? 62.15200 Section 62.15200 Protection of Environment... I do if I choose to monitor carbon dioxide instead of oxygen as a diluent gas? You must establish the relationship between oxygen and carbon dioxide during the initial evaluation of your continuous...

  11. 40 CFR 62.15200 - What must I do if I choose to monitor carbon dioxide instead of oxygen as a diluent gas?

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... carbon dioxide instead of oxygen as a diluent gas? 62.15200 Section 62.15200 Protection of Environment... I do if I choose to monitor carbon dioxide instead of oxygen as a diluent gas? You must establish the relationship between oxygen and carbon dioxide during the initial evaluation of your continuous...

  12. 40 CFR 62.15200 - What must I do if I choose to monitor carbon dioxide instead of oxygen as a diluent gas?

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... carbon dioxide instead of oxygen as a diluent gas? 62.15200 Section 62.15200 Protection of Environment... I do if I choose to monitor carbon dioxide instead of oxygen as a diluent gas? You must establish the relationship between oxygen and carbon dioxide during the initial evaluation of your continuous...

  13. 40 CFR 62.15200 - What must I do if I choose to monitor carbon dioxide instead of oxygen as a diluent gas?

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... carbon dioxide instead of oxygen as a diluent gas? 62.15200 Section 62.15200 Protection of Environment... I do if I choose to monitor carbon dioxide instead of oxygen as a diluent gas? You must establish the relationship between oxygen and carbon dioxide during the initial evaluation of your continuous...

  14. Designing management strategies for carbon dioxide storage and utilization under uncertainty using inexact modelling

    NASA Astrophysics Data System (ADS)

    Wang, Yu; Fan, Jie; Xu, Ye; Sun, Wei; Chen, Dong

    2017-06-01

    Effective application of carbon capture, utilization and storage (CCUS) systems could help to alleviate the influence of climate change by reducing carbon dioxide (CO2) emissions. The research objective of this study is to develop an equilibrium chance-constrained programming model with bi-random variables (ECCP model) for supporting the CCUS management system under random circumstances. The major advantage of the ECCP model is that it tackles random variables as bi-random variables with a normal distribution, where the mean values follow a normal distribution. This could avoid irrational assumptions and oversimplifications in the process of parameter design and enrich the theory of stochastic optimization. The ECCP model is solved by an equilibrium change-constrained programming algorithm, which provides convenience for decision makers to rank the solution set using the natural order of real numbers. The ECCP model is applied to a CCUS management problem, and the solutions could be useful in helping managers to design and generate rational CO2-allocation patterns under complexities and uncertainties.

  15. Microfluidic platform for studying the electrochemical reduction of carbon dioxide

    NASA Astrophysics Data System (ADS)

    Whipple, Devin Talmage

    Diminishing supplies of conventional energy sources and growing concern over greenhouse gas emissions present significant challenges to supplying the world's rapidly increasing demand for energy. The electrochemical reduction of carbon dioxide has the potential to address many of these issues by providing a means of storing electricity in chemical form. Storing electrical energy as chemicals is beneficial for leveling the output of clean, but intermittent renewable energy sources such as wind and solar. Electrical energy stored as chemicals can also be used as carbon neutral fuels for portable applications allowing petroleum derived fuels in the transportation sector to be replaced by more environmentally friendly energy sources. However, to be a viable technology, the electrochemical reduction of carbon dioxide needs to have both high current densities and energetic efficiencies (Chapter 1). Although many researchers have studied the electrochemical reduction of CO2 including parameters such as catalysts, electrolytes and temperature, further investigation is needed to improve the understanding of this process and optimize the performance (Chapter 2). This dissertation reports the development and validation of a microfluidic reactor for the electrochemical reduction of CO2 (Chapter 3). The design uses a flowing liquid electrolyte instead of the typical polymer electrolyte membrane. In addition to other benefits, this flowing electrolyte gives the reactor great flexibility, allowing independent analysis of each electrode and the testing of a wide variety of conditions. In this work, the microfluidic reactor has been used in the following areas: • Comparison of different metal catalysts for the reduction of CO2 to formic acid and carbon monoxide (Chapter 4). • Investigation of the effects of the electrolyte pH on the reduction of CO2 to formic acid and carbon monoxide (Chapter 5). • Study of amine based electrolytes for lowering the overpotentials for CO2 reduction and suppressing undesirable hydrogen evolution (Chapter 6). • Investigation of the effects of reaction temperature on the Faradaic efficiency and current density for CO2 reduction on several catalysts (Chapter 7). These studies demonstrate the utility of this flexible reactor design and provide increased understanding of the electrochemical reduction of CO2 and the critical parameters for optimization of this process.

  16. Classroom Demonstration: Combustion of Diamond to Carbon Dioxide Followed by Reduction to Graphite

    ERIC Educational Resources Information Center

    Miyauchi, Takuya; Kamata, Masahiro

    2012-01-01

    An educational demonstration shows the combustion of carbon to carbon dioxide and then the reduction of carbon dioxide to carbon. A melee diamond is the source of the carbon and the reaction is carried out in a closed flask. The demonstration helps students to realize that diamonds are made of carbon and that atoms do not change or vanish in…

  17. Enhanced astaxanthin accumulation in Haematococcus pluvialis using high carbon dioxide concentration and light illumination.

    PubMed

    Christian, David; Zhang, Jun; Sawdon, Alicia J; Peng, Ching-An

    2018-05-01

    In this study, an economical two-stage method was proposed for the production of natural astaxanthin from Haematococcus pluvialis without a medium replacement step. In stage 1, H. pluvialis were grown under low light illumination until they reached optimal biomass. In stage 2, cells were switched to astaxanthin induction conditions utilizing the combination of high light illumination and elevated carbon dioxide levels (5 or 15%). The introduction of CO 2 altered the C/N balance creating a nutrient deficiency without a change of media. The resulting astaxanthin yield was 2-3 times that of using either stressor alone. This astaxanthin induction method has many advantages over current methods including no medium replacement and a short induction time of less than four days. Copyright © 2018 Elsevier Ltd. All rights reserved.

  18. Analysis of exergy efficiency of a super-critical compressed carbon dioxide energy-storage system based on the orthogonal method.

    PubMed

    He, Qing; Hao, Yinping; Liu, Hui; Liu, Wenyi

    2018-01-01

    Super-critical carbon dioxide energy-storage (SC-CCES) technology is a new type of gas energy-storage technology. This paper used orthogonal method and variance analysis to make significant analysis on the factors which would affect the thermodynamics characteristics of the SC-CCES system and obtained the significant factors and interactions in the energy-storage process, the energy-release process and the whole energy-storage system. Results have shown that the interactions in the components have little influence on the energy-storage process, the energy-release process and the whole energy-storage process of the SC-CCES system, the significant factors are mainly on the characteristics of the system component itself, which will provide reference for the optimization of the thermal properties of the energy-storage system.

  19. Selective Metallization of Well Aligned PS-b-P2VP Block Copolymers in Thin Films and in Confined Geometries

    NASA Astrophysics Data System (ADS)

    Sievert, James D.; Watkins, James J.; Russell, Thomas P.

    2006-03-01

    Well aligned, microphase-separated structures of styrene-2-vinylpyridine block copolymers are being used as templates for macromolecule-metal nanocomposites. These composites are either prepared as thin films or confined in nanoporous aluminum oxide membranes. Under optimal conditions, templates are prepared as thin films or confined nanorods and metallized without disturbing the ordered structure. We have developed a procedure that deposits metal within the polymer using supercritical carbon dioxide-soluble metal precursors. The use of supercritical carbon dioxide allows for selective metallization of the polymer at or below the glass transition, without disrupting the morphology. In addition, similar procedures have been investigated using metal salts and acids. Using these techniques, metals and metal-sulfides including silver, gold, platinum and zinc sulfide have been selectively deposited.

  20. Analysis of exergy efficiency of a super-critical compressed carbon dioxide energy-storage system based on the orthogonal method

    PubMed Central

    He, Qing; Liu, Hui; Liu, Wenyi

    2018-01-01

    Super-critical carbon dioxide energy-storage (SC-CCES) technology is a new type of gas energy-storage technology. This paper used orthogonal method and variance analysis to make significant analysis on the factors which would affect the thermodynamics characteristics of the SC-CCES system and obtained the significant factors and interactions in the energy-storage process, the energy-release process and the whole energy-storage system. Results have shown that the interactions in the components have little influence on the energy-storage process, the energy-release process and the whole energy-storage process of the SC-CCES system, the significant factors are mainly on the characteristics of the system component itself, which will provide reference for the optimization of the thermal properties of the energy-storage system. PMID:29634742

  1. Carbonic acid as a reserve of carbon dioxide on icy moons: The formation of carbon dioxide (CO{sub 2}) in a polar environment

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Jones, Brant M.; Kaiser, Ralf I.; Strazzulla, Giovanni, E-mail: brantmj@hawaii.edu

    Carbon dioxide (CO{sub 2}) has been detected on the surface of several icy moons of Jupiter and Saturn via observation of the ν{sub 3} band with the Near-Infrared Mapping Spectrometer on board the Galileo spacecraft and the Visible-Infrared Mapping Spectrometer on board the Cassini spacecraft. Interestingly, the CO{sub 2} band for several of these moons exhibits a blueshift along with a broader profile than that seen in laboratory studies and other astrophysical environments. As such, numerous attempts have been made in order to clarify this abnormal behavior; however, it currently lacks an acceptable physical or chemical explanation. We present amore » rather surprising result pertaining to the synthesis of carbon dioxide in a polar environment. Here, carbonic acid was synthesized in a water (H{sub 2}O)-carbon dioxide (CO{sub 2}) (1:5) ice mixture exposed to ionizing radiation in the form of 5 keV electrons. The irradiated ice mixture was then annealed, producing pure carbonic acid which was then subsequently irradiated, recycling water and carbon dioxide. However, the observed carbon dioxide ν{sub 3} band matches almost exactly with that observed on Callisto; subsequent temperature program desorption studies reveal that carbon dioxide synthesized under these conditions remains in solid form until 160 K, i.e., the sublimation temperature of water. Consequently, our results suggest that carbon dioxide on Callisto as well as other icy moons is indeed complexed with water rationalizing the shift in peak frequency, broad profile, and the solid state existence on these relatively warm moons.« less

  2. Fixation of carbon dioxide into dimethyl carbonate over ...

    EPA Pesticide Factsheets

    A titanium-based zeolitic thiophene-benzimidazolate framework has been designed for the direct synthesis of dimethyl carbonate (DMC) from methanol and carbon dioxide. The developed catalyst activates carbon dioxide and delivers over 16% yield of DMC without the use of any dehydrating agent or requirement for azeotropic distillation. Prepared for submission to Nature Scientific reports.

  3. The Path of Carbon in Photosynthesis IX. Photosynthesis, Photoreduction, and the Hydrogen-Oxygen-Carbon Dioxide Dark Reaction

    DOE R&D Accomplishments Database

    Badin, E. J.; Calvin, M.

    1950-02-01

    A comparison of the rates of fixation of Carbon 14 dioxide in algae for the processes of photosynthesis, photoreduction and the hydrogen-oxygen-carbon dioxide dark reaction has been made. For the same series of experiments, rates of incorporation of tracer carbon into the separate soluble components using the radiogram method have been determined. The mechanism of carbon dioxide uptake has been shown to occur via two distinct paths. In all cases studied, essentially the same compounds appear radioactive. The distribution with time, however, differs markedly.

  4. Modeling of Revitalization of Atmospheric Water

    NASA Technical Reports Server (NTRS)

    Coker, Robert; Knox, Jim

    2014-01-01

    The Atmosphere Revitalization Recovery and Environmental Monitoring (ARREM) project was initiated in September of 2011 as part of the Advanced Exploration Systems (AES) program. Under the ARREM project, testing of sub-scale and full-scale systems has been combined with multiphysics computer simulations for evaluation and optimization of subsystem approaches. In particular, this paper describes the testing and modeling of the water desiccant subsystem of the carbon dioxide removal assembly (CDRA). The goal is a full system predictive model of CDRA to guide system optimization and development.

  5. DOE Office of Scientific and Technical Information (OSTI.GOV)

    T. Nakamura; C.L. Senior

    Most of the anthropogenic emissions of carbon dioxide result from the combustion of fossil fuels for energy production. Photosynthesis has long been recognized as a means, at least in theory, to sequester anthropogenic carbon dioxide. Aquatic microalgae have been identified as fast growing species whose carbon fixing rates are higher than those of land-based plants by one order of magnitude. Physical Sciences Inc. (PSI), Aquasearch, and the Hawaii Natural Energy Institute at the University of Hawaii are jointly developing technologies for recovery and sequestration of CO{sub 2} from stationary combustion systems by photosynthesis of microalgae. The research is aimed primarilymore » at demonstrating the ability of selected species of microalgae to effectively fix carbon from typical power plant exhaust gases. This report covers the reporting period 1 October 2000 to 31 March 2005 in which PSI, Aquasearch and University of Hawaii conducted their tasks. This report discusses results of the work pertaining to five tasks: Task 1--Supply of CO2 from Power Plant Flue Gas to Photobioreactor; Task 2--Selection of Microalgae; Task 3--Optimization and Demonstration of Industrial Scale Photobioreactor; Task 4--Carbon Sequestration System Design; and Task 5--Economic Analysis. Based on the work conducted in each task summary conclusion is presented.« less

  6. Seasonal analyses of carbon dioxide and energy fluxes above an oil palm plantation using the eddy covariance method

    NASA Astrophysics Data System (ADS)

    Ibrahim, Anis; Haniff Harun, Mohd; Yusup, Yusri

    2017-04-01

    A study presents the measurements of carbon dioxide and latent and sensible heat fluxes above a mature oil palm plantation on mineral soil in Keratong, Pahang, Peninsular Malaysia. The sampling campaign was conducted over an 25-month period, from September 2013 to February 2015 and May 2016 to November 2016, using the eddy covariance method. The main aim of this work is to assess carbon dioxide and energy fluxes over this plantation at different time scales, seasonal and diurnal, and determine the effects of season and relevant meteorological parameters on the latter fluxes. Energy balance closure analyses gave a slope between latent and sensible heat fluxes and total incoming energy to be 0.69 with an R2 value of 0.86 and energy balance ratio of 0.80. The averaged net radiation was 108 W m-2. The results show that at the diurnal scale, carbon dioxide, latent and sensible heat fluxes exhibited a clear diurnal trend where carbon dioxide flux was at its minimum - 3.59 μmol m-2 s-1 in the mid-afternoon and maximum in the morning while latent and sensible behaved conversely to the carbon dioxide flux. The average carbon dioxide flux was - 0.37 μmol m-2 s-1. At the seasonal timescale, carbon dioxide fluxes did not show any apparent trend except during the Northeast Monsoon where the highest variability of the monthly means of carbon dioxide occurred.

  7. Elevated Carbon Dioxide in the Atmosphere: What Might It Mean for Loblolly Pine Plantation Forestry

    Treesearch

    John W. Groninger; Kurt H. Johnsen; John. R. Seiler; Rodney E. Will; David S. Ellsworth; Chris A. Maier

    1999-01-01

    Research with loblolly pine suggests that projected increases in atmospheric CO2 concentration will accelerate early growth and could result in shorter rotation length, reduced time until first commercial thinning, higher optimal planting density, and possibly higher maximum stocking level in managed stands. We discuss some of the physiological...

  8. EFFECTS OF CULTURE PARAMETERS ON DDT [1,1,1-TRICHLO- RO-2,2-BIS(4-CHLOROPHENYL) ETHANE] BIODEGRADATION BY PHANEROCHAETE CHRYSOSPORIUM

    EPA Science Inventory

    The lignin degrading system of the white rot fungus Phanerochaete chrysosporium is able to degrade a wide variety of structurally diverse organopollutants to carbon dioxide. Current research is focused on ways to increase or optimize rates of biodegradation in order to a...

  9. Cerebral blood flow response to changes in arterial carbon dioxide tension during hypothermic cardiopulmonary bypass in children

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Kern, F.H.; Ungerleider, R.M.; Quill, T.J.

    1991-04-01

    We examined the relationship of changes in partial pressure of carbon dioxide on cerebral blood flow responsiveness in 20 pediatric patients undergoing hypothermic cardiopulmonary bypass. Cerebral blood flow was measured during steady-state hypothermic cardiopulmonary bypass with the use of xenon 133 clearance methodology at two different arterial carbon dioxide tensions. During these measurements there was no significant change in mean arterial pressure, nasopharyngeal temperature, pump flow rate, or hematocrit value. Cerebral blood flow was found to be significantly greater at higher arterial carbon dioxide tensions (p less than 0.01), so that for every millimeter of mercury rise in arterial carbonmore » dioxide tension there was a 1.2 ml.100 gm-1.min-1 increase in cerebral blood flow. Two factors, deep hypothermia (18 degrees to 22 degrees C) and reduced age (less than 1 year), diminished the effect carbon dioxide had on cerebral blood flow responsiveness but did not eliminate it. We conclude that cerebral blood flow remains responsive to changes in arterial carbon dioxide tension during hypothermic cardiopulmonary bypass in infants and children; that is, increasing arterial carbon dioxide tension will independently increase cerebral blood flow.« less

  10. Production of magnesium metal

    DOEpatents

    Blencoe, James G [Harriman, TN; Anovitz, Lawrence M [Knoxville, TN; Palmer, Donald A [Oliver Springs, TN; Beard, James S [Martinsville, VA

    2010-02-23

    A process of producing magnesium metal includes providing magnesium carbonate, and reacting the magnesium carbonate to produce a magnesium-containing compound and carbon dioxide. The magnesium-containing compound is reacted to produce magnesium metal. The carbon dioxide is used as a reactant in a second process. In another embodiment of the process, a magnesium silicate is reacted with a caustic material to produce magnesium hydroxide. The magnesium hydroxide is reacted with a source of carbon dioxide to produce magnesium carbonate. The magnesium carbonate is reacted to produce a magnesium-containing compound and carbon dioxide. The magnesium-containing compound is reacted to produce magnesium metal. The invention further relates to a process for production of magnesium metal or a magnesium compound where an external source of carbon dioxide is not used in any of the reactions of the process. The invention also relates to the magnesium metal produced by the processes described herein.

  11. Revisiting the emissions-energy-trade nexus: evidence from the newly industrializing countries.

    PubMed

    Ahmed, Khalid; Shahbaz, Muhammad; Kyophilavong, Phouphet

    2016-04-01

    This paper applies Pedroni's panel cointegration approach to explore the causal relationship between trade openness, carbon dioxide emissions, energy consumption, and economic growth for the panel of newly industrialized economies (i.e., Brazil, India, China, and South Africa) over the period of 1970-2013. Our panel cointegration estimation results found majority of the variables cointegrated and confirm the long-run association among the variables. The Granger causality test indicates bidirectional causality between carbon dioxide emissions and energy consumption. A unidirectional causality is found running from trade openness to carbon dioxide emission and energy consumption and economic growth to carbon dioxide emissions. The results of causality analysis suggest that the trade liberalization in newly industrialized economies induces higher energy consumption and carbon dioxide emissions. Furthermore, the causality results are checked using an innovative accounting approach which includes forecast-error variance decomposition test and impulse response function. The long-run coefficients are estimated using fully modified ordinary least square (FMOLS) method, and results conclude that the trade openness and economic growth reduce carbon dioxide emissions in the long run. The results of FMOLS test sound the existence of environmental Kuznets curve hypothesis. It means that trade liberalization induces carbon dioxide emission with increased national output, but it offsets that impact in the long run with reduced level of carbon dioxide emissions.

  12. Carbon dioxide stripping in aquaculture -- part II: development of gas transfer models

    USGS Publications Warehouse

    Colt, John; Watten, Barnaby; Pfeiffer, Tim

    2012-01-01

    The basic mass transfer equation for gases such as oxygen and carbon dioxide can be derived from integration of the driving force equation. Because of the physical characteristics of the gas transfer processes, slightly different models are used for aerators tested under the non steady-state procedures, than for packed columns, or weirs. It is suggested that the standard condition for carbon dioxide should be 20 °C, 1 atm, CCO2=20 mg/kg, and XCO2=0.000285. The selection of the standard condition for carbon dioxide based on a fixed mole fraction ensures that standardized carbon dioxide transfer rates will be comparable even though the value of C*CO2 in the atmosphere is increasing with time. The computation of mass transfer for carbon dioxide is complicated by the impact of water depth and gas phase enrichment on the saturation concentration within the unit, although the importance of either factor depends strongly on the specific type of aerator. For some types of aerators, the most accurate gas phase model remains to be determined for carbon dioxide. The assumption that carbon dioxide can be treated as a non-reactive gas in packed columns may apply for cold acidic waters but not for warm alkaline waters.

  13. Environment and Materials Stewardship | NREL

    Science.gov Websites

    dioxide equivalent of natural gas in heating facilities and experiments; 105metric tons of carbon dioxide equivalent in fleet and equipment; 15 metric tons of carbon dioxide equivalent in fluorinated gases and refrigerants; and 10 metric tons of carbon dioxide equivalent in dry ice use in laboratories. Scope 2 accounts

  14. 40 CFR 62.15175 - What continuous emission monitoring systems must I install for gaseous pollutants?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ..., maintain, and operate continuous emission monitoring systems for oxygen (or carbon dioxide), sulfur dioxide, and carbon monoxide. If you operate a Class I municipal waste combustion unit, also install, calibrate... emission monitoring system for sulfur dioxide, nitrogen oxides, and oxygen (or carbon dioxide) at the...

  15. 40 CFR 60.1720 - What continuous emission monitoring systems must I install for gaseous pollutants?

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ..., maintain, and operate continuous emission monitoring systems for oxygen (or carbon dioxide), sulfur dioxide, and carbon monoxide. If you operate a Class I municipal waste combustion unit, also install, calibrate... emission monitoring systems for sulfur dioxide, nitrogen oxides, and oxygen (or carbon dioxide) at the...

  16. 40 CFR 60.1720 - What continuous emission monitoring systems must I install for gaseous pollutants?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ..., maintain, and operate continuous emission monitoring systems for oxygen (or carbon dioxide), sulfur dioxide, and carbon monoxide. If you operate a Class I municipal waste combustion unit, also install, calibrate... emission monitoring systems for sulfur dioxide, nitrogen oxides, and oxygen (or carbon dioxide) at the...

  17. 40 CFR 62.15175 - What continuous emission monitoring systems must I install for gaseous pollutants?

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ..., maintain, and operate continuous emission monitoring systems for oxygen (or carbon dioxide), sulfur dioxide, and carbon monoxide. If you operate a Class I municipal waste combustion unit, also install, calibrate... emission monitoring system for sulfur dioxide, nitrogen oxides, and oxygen (or carbon dioxide) at the...

  18. Selective free radical reactions using supercritical carbon dioxide.

    PubMed

    Cormier, Philip J; Clarke, Ryan M; McFadden, Ryan M L; Ghandi, Khashayar

    2014-02-12

    We report herein a means to modify the reactivity of alkenes, and particularly to modify their selectivity toward reactions with nonpolar reactants (e.g., nonpolar free radicals) in supercritical carbon dioxide near the critical point. Rate constants for free radical addition of the light hydrogen isotope muonium to ethylene, vinylidene fluoride, and vinylidene chloride in supercritical carbon dioxide are compared over a range of pressures and temperatures. Near carbon dioxide's critical point, the addition to ethylene exhibits critical speeding up, while the halogenated analogues display critical slowing. This suggests that supercritical carbon dioxide as a solvent may be used to tune alkene chemistry in near-critical conditions.

  19. Carbon dioxide hydrogenation catalysed by well-defined Mn(i) PNP pincer hydride complexes† †Electronic supplementary information (ESI) available: Experimental procedures, NMR and IR spectra, atomic coordinates for DFT optimized structures and computational details, and crystallographic data for 2. CCDC 1520528. For ESI and crystallographic data in CIF or other electronic format see DOI: 10.1039/c7sc00209b Click here for additional data file. Click here for additional data file.

    PubMed Central

    Bertini, Federica; Glatz, Mathias; Gorgas, Nikolaus; Stöger, Berthold; Peruzzini, Maurizio; Veiros, Luis F.

    2017-01-01

    The catalytic reduction of carbon dioxide is of great interest for its potential as a hydrogen storage method and to use carbon dioxide as C-1 feedstock. In an effort to replace expensive noble metal-based catalysts with efficient and cheap earth-abundant counterparts, we report the first example of Mn(i)-catalysed hydrogenation of CO2 to HCOOH. The hydride Mn(i) catalyst [Mn(PNPNH-iPr)(H)(CO)2] showed higher stability and activity than its Fe(ii) analogue. TONs up to 10 000 and quantitative yields were obtained after 24 h using DBU as the base at 80 °C and 80 bar total pressure. At catalyst loadings as low as 0.002 mol%, TONs greater than 30 000 could be achieved in the presence of LiOTf as the co-catalyst, which are among the highest activities reported for base-metal catalysed CO2 hydrogenations to date. PMID:28970889

  20. Antioxidant potential of Juglans nigra, black walnut, husks extracted using supercritical carbon dioxide with an ethanol modifier.

    PubMed

    Wenzel, Jonathan; Storer Samaniego, Cheryl; Wang, Lihua; Burrows, Laron; Tucker, Evan; Dwarshuis, Nathan; Ammerman, Michelle; Zand, Ali

    2017-03-01

    The black walnut, Junglas nigra, is indigenous to eastern North America, and abscission of its fruit occurs around October. The fruit consists of a husk, a hard shell, and kernel. The husk is commonly discarded in processing, though it contains phenolic compounds that exhibit antioxidant and antimicrobial properties. For this study, black walnut husks were extracted using supercritical carbon dioxide with an ethanol modifier. The effects of temperature, ethanol concentration, and drying of walnut husks prior to extraction upon antioxidant potential were evaluated using a factorial design of experiments. The solvent density was held constant at 0.75 g/mL. The optimal extraction conditions were found to be 68°C and 20 wt-% ethanol in supercritical carbon dioxide. At these conditions, the antioxidant potential as measured by the ferric reducing ability of plasma (FRAP) assay was 0.027 mmol trolox equivalent/g (mmol TE/g) for dried walnut husk and 0.054 mmol TE/g for walnut husks that were not dried. Antioxidant potential was also evaluated using the total phenolic content (TPC) and 1,1-diphenyl-2-picryl-hydrazyl (DPPH) assays and the FRAP assay was found to linearly correlate to the TPC assay.

  1. Pre-Combustion Carbon Dioxide Capture by a New Dual Phase Ceramic-Carbonate Membrane Reactor

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Lin, Jerry Y. S.

    2015-01-31

    This report documents synthesis, characterization and carbon dioxide permeation and separation properties of a new group of ceramic-carbonate dual-phase membranes and results of a laboratory study on their application for water gas shift reaction with carbon dioxide separation. A series of ceramic-carbonate dual phase membranes with various oxygen ionic or mixed ionic and electronic conducting metal oxide materials in disk, tube, symmetric, and asymmetric geometric configurations was developed. These membranes, with the thickness of 10 μm to 1.5 mm, show CO 2 permeance in the range of 0.5-5×10 -7 mol·m -2·s -1·Pa -1 in 500-900°C and measured CO 2/N 2more » selectivity of up to 3000. CO 2 permeation mechanism and factors that affect CO 2 permeation through the dual-phase membranes have been identified. A reliable CO 2 permeation model was developed. A robust method was established for the optimization of the microstructures of ceramic-carbonate membranes. The ceramic-carbonate membranes exhibit high stability for high temperature CO 2 separations and water gas shift reaction. Water gas shift reaction in the dual-phase membrane reactors was studied by both modeling and experiments. It is found that high temperature syngas water gas shift reaction in tubular ceramic-carbonate dual phase membrane reactor is feasible even without catalyst. The membrane reactor exhibits good CO 2 permeation flux, high thermal and chemical stability and high thermal shock resistance. Reaction and separation conditions in the membrane reactor to produce hydrogen of 93% purity and CO 2 stream of >95% purity, with 90% CO 2 capture have been identified. Integration of the ceramic-carbonate dual-phase membrane reactor with IGCC process for carbon dioxide capture was analyzed. A methodology was developed to identify optimum operation conditions for a membrane tube of given dimensions that would treat coal syngas with targeted performance. The calculation results show that the dual-phase membrane reactor could improve IGCC process efficiency but the cost of the membrane reactor with membranes having current CO 2 permeance is high. Further research should be directed towards improving the performance of the membranes and developing cost-effective, scalable methods for fabrication of dual-phase membranes and membrane reactors.« less

  2. Carbon dioxide capture process with regenerable sorbents

    DOEpatents

    Pennline, Henry W.; Hoffman, James S.

    2002-05-14

    A process to remove carbon dioxide from a gas stream using a cross-flow, or a moving-bed reactor. In the reactor the gas contacts an active material that is an alkali-metal compound, such as an alkali-metal carbonate, alkali-metal oxide, or alkali-metal hydroxide; or in the alternative, an alkaline-earth metal compound, such as an alkaline-earth metal carbonate, alkaline-earth metal oxide, or alkaline-earth metal hydroxide. The active material can be used by itself or supported on a substrate of carbon, alumina, silica, titania or aluminosilicate. When the active material is an alkali-metal compound, the carbon-dioxide reacts with the metal compound to generate bicarbonate. When the active material is an alkaline-earth metal, the carbon dioxide reacts with the metal compound to generate carbonate. Spent sorbent containing the bicarbonate or carbonate is moved to a second reactor where it is heated or treated with a reducing agent such as, natural gas, methane, carbon monoxide hydrogen, or a synthesis gas comprising of a combination of carbon monoxide and hydrogen. The heat or reducing agent releases carbon dioxide gas and regenerates the active material for use as the sorbent material in the first reactor. New sorbent may be added to the regenerated sorbent prior to subsequent passes in the carbon dioxide removal reactor.

  3. Novel single stripper with side-draw to remove ammonia and sour gas simultaneously for coal-gasification wastewater treatment and the industrial implementation

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Feng, D.C.; Yu, Z.J.; Chen, Y.

    2009-06-15

    A large amount of wastewater is produced in the Lurgi coal-gasification process with the complex compounds carbon dioxide, ammonia, phenol, etc., which cause a serious environmental problem. In this paper, a novel stripper operated at elevated pressure is designed to improve the pretreatment process. In this technology, two noticeable improvements were established. First, the carbon dioxide and ammonia were removed simultaneously in a single stripper where sour gas (mainly carbon dioxide) is removed from the tower top and the ammonia vapor is drawn from the side and recovered by partial condensation. Second, the ammonia is removed before the phenol recoverymore » to reduce the pH value of the subsequent extraction units, so as the phenol removal performance of the extraction is greatly improved. To ensure the operational efficiency, some key operational parameters are analyzed and optimized though simulation. It is shown that when the top temperature is kept at 40 C and the weight ratio of the side draw to the feed is above 9%, the elevated pressures can ensure the removal efficiency of NH{sub 3} and carbon dioxide and the desired purified water as the bottom product of the unit is obtained. A real industrial application demonstrates the attractiveness of the new technique: it removes 99.9% CO{sub 2} and 99.6% ammonia, compared to known techniques which remove 66.5% and 94.4%, respectively. As a result, the pH value of the wastewater is reduced from above 9 to below 7. This ensures that the phenol removal ratio is above 93% in the following extraction units. The operating cost is lower than that of known techniques, and the operation is simplified.« less

  4. Development of a prototype regenerable carbon dioxide absorber

    NASA Technical Reports Server (NTRS)

    Onischak, M.

    1976-01-01

    Design information was obtained for a new, regenerable carbon dioxide control system for extravehicular activity life support systems. Solid potassium carbonate was supported in a thin porous sheet form and fabricated into carbon dioxide absorber units. Carbon dioxide and water in the life support system atmosphere react with the potassium carbonate and form potassium bicarbonate. The bicarbonate easily reverts to the carbonate by heating to 150 deg C. The methods of effectively packing the sorbent material into EVA-sized units and the effects of inlet concentrations, flowrate, and temperature upon performance were investigated. The cycle life of the sorbent upon the repeated thermal regenerations was demonstrated through 90 cycles.

  5. Relative Permeabilities of Plastic Films to Water and Carbon Dioxide

    PubMed Central

    Woolley, Joseph T.

    1967-01-01

    The permeabilities of several types of plastic films to water and to carbon dioxide were measured. No material was found to have a carbon dioxide permeability as great as its water permeability. PMID:16656548

  6. Investigations about the quantitative changes of carbon dioxide production in humans. Report 2: Carbon dioxide production during fever and its relationship with heat production

    NASA Technical Reports Server (NTRS)

    Liebermeister, C.

    1978-01-01

    Investigations are cited and explained for carbon dioxide production during fever and its relationship with heat production. The general topics of discussion are: (1) carbon dioxide production for alternating fever attacks; (2) heat balance during the perspiration phase; (3) heat balance during the chill phase; (4) the theory of fever; and (5) chill phase for other fever attacks.

  7. Hydraulic studies of drilling microbores with supercritical steam, nitrogen and carbon dioxide

    DOE Data Explorer

    Ken Oglesby

    2010-01-01

    Hydraulic studies of drilling microbores at various depths and with various hole sizes, tubing, fluids and rates showed theoretical feasibility. WELLFLO SIMULATIONS REPORT STEP 4: DRILLING 10,000 FT WELLS WITH SUPERCRITICAL STEAM, NITROGEN AND CARBON DIOXIDE STEP 5: DRILLING 20,000 FT WELLS WITH SUPERCRITICAL STEAM, NITROGEN AND CARBON DIOXIDE STEP 6: DRILLING 30,000 FT WELLS WITH SUPERCRITICAL STEAM, NITROGEN AND CARBON DIOXIDE Mehmet Karaaslan, MSI

  8. Carbon Dioxide Detection and Indoor Air Quality Control.

    PubMed

    Bonino, Steve

    2016-04-01

    When building ventilation is reduced, energy is saved because it is not necessary to heat or cool as much outside air. Reduced ventilation can result in higher levels of carbon dioxide, which may cause building occupants to experience symptoms. Heating or cooling for ventilation air can be enhanced by a DCV system, which can save energy while providing a comfortable environment. Carbon dioxide concentrations within a building are often used to indicate whether adequate fresh air is being supplied to the building. These DCV systems use carbon dioxide sensors in each space or in the return air and adjust the ventilation based on carbon dioxide concentration; the higher the concentration, the more people occupy the space relative to the ventilation rate. With a carbon dioxide sensor DCV system, the fresh air ventilation rate varies based on the number ofpeople in the space, saving energy while maintaining a safe and comfortable environment.

  9. Advanced air revitalization system modeling and testing

    NASA Technical Reports Server (NTRS)

    Dall-Baumann, Liese; Jeng, Frank; Christian, Steve; Edeer, Marybeth; Lin, Chin

    1990-01-01

    To support manned lunar and Martian exploration, an extensive evaluation of air revitalization subsystems (ARS) is being conducted. The major operations under study include carbon dioxide removal and reduction; oxygen and nitrogen production, storage, and distribution; humidity and temperature control; and trace contaminant control. A comprehensive analysis program based on a generalized block flow model was developed to facilitate the evaluation of various processes and their interaction. ASPEN PLUS was used in modelling carbon dioxide removal and reduction. Several life support test stands were developed to test new and existing technologies for their potential applicability in space. The goal was to identify processes which use compact, lightweight equipment and maximize the recovery of oxygen and water. The carbon dioxide removal test stands include solid amine/vacuum desorption (SAVD), regenerative silver oxide chemisorption, and electrochemical carbon dioxide concentration (EDC). Membrane-based carbon dioxide removal and humidity control, catalytic reduction of carbon dioxide, and catalytic oxidation of trace contaminants were also investigated.

  10. Combustion systems and power plants incorporating parallel carbon dioxide capture and sweep-based membrane separation units to remove carbon dioxide from combustion gases

    DOEpatents

    Wijmans, Johannes G [Menlo Park, CA; Merkel, Timothy C [Menlo Park, CA; Baker, Richard W [Palo Alto, CA

    2011-10-11

    Disclosed herein are combustion systems and power plants that incorporate sweep-based membrane separation units to remove carbon dioxide from combustion gases. In its most basic embodiment, the invention is a combustion system that includes three discrete units: a combustion unit, a carbon dioxide capture unit, and a sweep-based membrane separation unit. In a preferred embodiment, the invention is a power plant including a combustion unit, a power generation system, a carbon dioxide capture unit, and a sweep-based membrane separation unit. In both of these embodiments, the carbon dioxide capture unit and the sweep-based membrane separation unit are configured to be operated in parallel, by which we mean that each unit is adapted to receive exhaust gases from the combustion unit without such gases first passing through the other unit.

  11. Geologic map showing springs rich in carbon dioxide or or chloride in California

    USGS Publications Warehouse

    Barnes, Ivan; Irwin, William P.; Gibson, H.A.

    1975-01-01

    Carbon dioxide- and chloride-rich springs occur in all geologic provinces in California, but are most abundant in the Coast Ranges and the Great Valley. The carbon-dioxide-rich springs issue mainly from Franciscan terrane; they also are rich in boron and are of the metamorphic type (White, 1957). Based on isotopic data, either the carbon dioxide or the water, or both, may be of metamorphic origin. Because of high magnesium values, the water of many of the carbon-dioxide-rich springs is thought to have passed through serpentinite. The chloride-rich waters are most common in rocks of the Great Valley sequence. Nearly all are more dilute than present-day sea water. The similarity in isotopic compositions of the metamorphic carbon-dioxide-rich water and the chloride-rich water may indicate a similar extent of water-rock interaction.

  12. Effect of Novel Quercetin Titanium Dioxide-Decorated Multi-Walled Carbon Nanotubes Nanocomposite on Bacillus subtilis Biofilm Development

    PubMed Central

    Raie, Diana S.; Mhatre, Eisha; El-Desouki, Doaa S.; Labena, Ahmed; El-Ghannam, Gamal; Farahat, Laila A.; Youssef, Tareq; Fritzsche, Wolfgang; Kovács, Ákos T.

    2018-01-01

    The present work was targeted to design a surface against cell seeding and adhering of bacteria, Bacillus subtilis. A multi-walled carbon nanotube/titanium dioxide nano-power was produced via simple mixing of carbon nanotube and titanium dioxide nanoparticles during the sol-gel process followed by heat treatment. Successfully, quercetin was immobilized on the nanocomposite via physical adsorption to form a quercetin/multi-walled carbon nanotube/titanium dioxide nanocomposite. The adhesion of bacteria on the coated-slides was verified after 24 h using confocal laser-scanning microscopy. Results indicated that the quercetin/multi-walled carbon nanotube/titanium dioxide nanocomposite had more negativity and higher recovery by glass surfaces than its counterpart. Moreover, coating surfaces with the quercetin-modified nanocomposite lowered both hydrophilicity and surface-attached bacteria compared to surfaces coated with the multi-walled carbon nanotubes/titanium dioxide nanocomposite. PMID:29346268

  13. Production of magnesium metal

    DOEpatents

    Blencoe, James G [Harriman, TN; Anovitz, Lawrence M [Knoxville, TN; Palmer, Donald A [Oliver Springs, TN; Beard, James S [Martinsville, VA

    2012-04-10

    A process of producing magnesium metal includes providing magnesium carbonate, and reacting the magnesium carbonate to produce a magnesium-containing compound and carbon dioxide. The magnesium-containing compound is reacted to produce magnesium metal. The carbon dioxide is used as a reactant in a second process. In another embodiment of the process, a magnesium silicate is reacted with a caustic material to produce magnesium hydroxide. The magnesium hydroxide is reacted with a source of carbon dioxide to produce magnesium carbonate. The magnesium carbonate is reacted to produce a magnesium-containing compound and carbon dioxide. The magnesium-containing compound is reacted to produce magnesium metal. The invention also relates to the magnesium metal produced by the processes described herein.

  14. Ruthenium-catalysed alkoxycarbonylation of alkenes with carbon dioxide.

    PubMed

    Wu, Lipeng; Liu, Qiang; Fleischer, Ivana; Jackstell, Ralf; Beller, Matthias

    2014-01-01

    Alkene carbonylations represent a major technology for the production of value-added bulk and fine chemicals. Nowadays, all industrial carbonylation processes make use of highly toxic and flammable carbon monoxide. Here we show the application of abundantly available carbon dioxide as C1 building block for the alkoxycarbonylations of industrially important olefins in the presence of a convenient and inexpensive ruthenium catalyst system. In our system, carbon dioxide works much better than the traditional combination of carbon monoxide and alcohols. The unprecedented in situ formation of carbon monoxide from carbon dioxide and alcohols permits an efficient synthesis of carboxylic acid esters, which can be used as detergents and polymer-building blocks. Notably, this transformation allows the catalytic formation of C-C bonds with carbon dioxide as C1 source and avoids the use of sensitive and/or expensive reducing agents (for example, Grignard reagents, diethylzinc or triethylaluminum).

  15. Encapsulated liquid sorbents for carbon dioxide capture

    NASA Astrophysics Data System (ADS)

    Vericella, John J.; Baker, Sarah E.; Stolaroff, Joshuah K.; Duoss, Eric B.; Hardin, James O.; Lewicki, James; Glogowski, Elizabeth; Floyd, William C.; Valdez, Carlos A.; Smith, William L.; Satcher, Joe H.; Bourcier, William L.; Spadaccini, Christopher M.; Lewis, Jennifer A.; Aines, Roger D.

    2015-02-01

    Drawbacks of current carbon dioxide capture methods include corrosivity, evaporative losses and fouling. Separating the capture solvent from infrastructure and effluent gases via microencapsulation provides possible solutions to these issues. Here we report carbon capture materials that may enable low-cost and energy-efficient capture of carbon dioxide from flue gas. Polymer microcapsules composed of liquid carbonate cores and highly permeable silicone shells are produced by microfluidic assembly. This motif couples the capacity and selectivity of liquid sorbents with high surface area to facilitate rapid and controlled carbon dioxide uptake and release over repeated cycles. While mass transport across the capsule shell is slightly lower relative to neat liquid sorbents, the surface area enhancement gained via encapsulation provides an order-of-magnitude increase in carbon dioxide absorption rates for a given sorbent mass. The microcapsules are stable under typical industrial operating conditions and may be used in supported packing and fluidized beds for large-scale carbon capture.

  16. W.A. Parish Post Combustion CO 2 Capture and Sequestration Project Final Public Design Report

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Armpriester, Anthony

    The Petra Nova Project is a commercial scale post-combustion carbon dioxide capture project that is being developed by a joint venture between NRG Energy (NRG) and JX Nippon Oil and Gas Exploration (JX). The project is designed to separate and capture carbon dioxide from an existing coal-fired unit's flue gas slipstream at NRG's W.A. Parish Generation Station located southwest of Houston, Texas. The captured carbon dioxide will be transported by pipeline and injected into the West Ranch oil field to boost oil production. The project, which is partially funded by financial assistance from the U.S. Department of Energy will usemore » Mitsubishi Heavy Industries of America, Inc.'s Kansai Mitsubishi Carbon Dioxide Recovery (KM-CDR(R)) advanced amine-based carbon dioxide absorption technology to treat and capture at least 90% of the carbon dioxide from a 240 megawatt equivalent flue gas slipstream off of Unit 8 at W.A. Parish. The project will capture approximately 5,000 tons of carbon dioxide per day or 1.5 million tons per year that Unit 8 would otherwise emit, representing the largest commercial scale deployment of post-combustion carbon dioxide capture at a coal power plant to date. The joint venture issued full notice to proceed in July 2014 and when complete, the project is expected to be the world's largest post-combustion carbon dioxide capture facility on an existing coal plant. The detailed engineering is sufficiently complete to prepare and issue the Final Public Design Report.« less

  17. Extraction of Carbon Dioxide and Hydrogen from Seawater and Hydrocarbon Production Therefrom

    DTIC Science & Technology

    2016-04-05

    extracted from the acidified seawater. Optionally, the ion exchange reaction can be conducted under conditions which produce hydrogen as well as carbon dioxide. The carbon dioxide and hydrogen may be used to produce hydrocarbons.

  18. International Space Station Carbon Dioxide Removal Assembly Testing

    NASA Technical Reports Server (NTRS)

    Knox, James C.

    2000-01-01

    Performance testing of the International Space Station Carbon Dioxide Removal Assembly flight hardware in the United States Laboratory during 1999 is described. The CDRA exceeded carbon dioxide performance specifications and operated flawlessly. Data from this test is presented.

  19. Method for enhanced oil recovery

    DOEpatents

    Comberiati, Joseph R.; Locke, Charles D.; Kamath, Krishna I.

    1980-01-01

    The present invention is directed to an improved method for enhanced recovery of oil from relatively "cold" reservoirs by carbon dioxide flooding. In oil reservoirs at a temperature less than the critical temperature of 87.7.degree. F. and at a pore pressure greater than the saturation pressure of carbon dioxide at the temperature of the reservoir, the carbon dioxide remains in the liquid state which does not satisfactorily mix with the oil. However, applicants have found that carbon dioxide can be vaporized in situ in the reservoir by selectively reducing the pore pressure in the reservoir to a value less than the particular saturated vapor pressure so as to greatly enhance the mixing of the carbon dioxide with the oil.

  20. Decreased abundance of crustose coralline algae due to ocean acidification

    USGS Publications Warehouse

    Kuffner, Ilsa B.; Andersson, Andreas J; Jokiel, Paul L.; Rodgers, Ku'ulei S.; Mackenzie, Fred T.

    2008-01-01

    Owing to anthropogenic emissions, atmospheric concentrations of carbon dioxide could almost double between 2006 and 2100 according to business-as-usual carbon dioxide emission scenarios1. Because the ocean absorbs carbon dioxide from the atmosphere2, 3, 4, increasing atmospheric carbon dioxide concentrations will lead to increasing dissolved inorganic carbon and carbon dioxide in surface ocean waters, and hence acidification and lower carbonate saturation states2, 5. As a consequence, it has been suggested that marine calcifying organisms, for example corals, coralline algae, molluscs and foraminifera, will have difficulties producing their skeletons and shells at current rates6, 7, with potentially severe implications for marine ecosystems, including coral reefs6, 8, 9, 10, 11. Here we report a seven-week experiment exploring the effects of ocean acidification on crustose coralline algae, a cosmopolitan group of calcifying algae that is ecologically important in most shallow-water habitats12, 13, 14. Six outdoor mesocosms were continuously supplied with sea water from the adjacent reef and manipulated to simulate conditions of either ambient or elevated seawater carbon dioxide concentrations. The recruitment rate and growth of crustose coralline algae were severely inhibited in the elevated carbon dioxide mesocosms. Our findings suggest that ocean acidification due to human activities could cause significant change to benthic community structure in shallow-warm-water carbonate ecosystems.

  1. 46 CFR 95.15-1 - Application.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... EQUIPMENT Carbon Dioxide Extinguishing Systems, Details § 95.15-1 Application. (a) Where a carbon dioxide... are based on a “high pressure system,” i.e., one in which the carbon dioxide is stored in liquid form at atmospheric temperature. Details for “low pressure systems,” i. e., those in which the carbon...

  2. 46 CFR 95.15-1 - Application.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... EQUIPMENT Carbon Dioxide Extinguishing Systems, Details § 95.15-1 Application. (a) Where a carbon dioxide... are based on a “high pressure system,” i.e., one in which the carbon dioxide is stored in liquid form at atmospheric temperature. Details for “low pressure systems,” i. e., those in which the carbon...

  3. 46 CFR 95.15-1 - Application.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... EQUIPMENT Carbon Dioxide Extinguishing Systems, Details § 95.15-1 Application. (a) Where a carbon dioxide... are based on a “high pressure system,” i.e., one in which the carbon dioxide is stored in liquid form at atmospheric temperature. Details for “low pressure systems,” i. e., those in which the carbon...

  4. 46 CFR 95.15-1 - Application.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... EQUIPMENT Carbon Dioxide Extinguishing Systems, Details § 95.15-1 Application. (a) Where a carbon dioxide... are based on a “high pressure system,” i.e., one in which the carbon dioxide is stored in liquid form at atmospheric temperature. Details for “low pressure systems,” i. e., those in which the carbon...

  5. Carbon Dioxide and the Greenhouse Effect: A Problem Evaluation Activity.

    ERIC Educational Resources Information Center

    Brewer, Carol A.; Beiswenger, Jane M.

    1993-01-01

    Describes exercises to examine the global carbon cycle. Students are asked to predict consequences of increased carbon dioxide emissions into the atmosphere and to suggest ways to mitigate problems associated with these higher levels of atmospheric carbon dioxide. A comparison modeling exercise examines some of the variables related to the success…

  6. Determination of diffusion coefficients of carbon dioxide in water between 268 and 473 K in a high-pressure capillary optical cell with in situ Raman spectroscopic measurements

    USGS Publications Warehouse

    Lu, Wanjun; Guo, Huirong; Chou, I.-Ming; Burruss, R.C.; Li, Lanlan

    2013-01-01

    Accurate values of diffusion coefficients for carbon dioxide in water and brine at reservoir conditions are essential to our understanding of transport behavior of carbon dioxide in subsurface pore space. However, the experimental data are limited to conditions at low temperatures and pressures. In this study, diffusive transfer of carbon dioxide in water at pressures up to 45 MPa and temperatures from 268 to 473 K was observed within an optical capillary cell via time-dependent Raman spectroscopy. Diffusion coefficients were estimated by the least-squares method for the measured variations in carbon dioxide concentration in the cell at various sample positions and time. At the constant pressure of 20 MPa, the measured diffusion coefficients of carbon dioxide in water increase with increasing temperature from 268 to 473 K. The relationship between diffusion coefficient of carbon dioxide in water [D(CO2) in m2/s] and temperature (T in K) was derived with Speedy–Angell power-law approach as: D(CO2)=D0[T/Ts-1]m where D0 = 13.942 × 10−9 m2/s, Ts = 227.0 K, and m = 1.7094. At constant temperature, diffusion coefficients of carbon dioxide in water decrease with pressure increase. However, this pressure effect is rather small (within a few percent).

  7. A new look at atmospheric carbon dioxide

    NASA Astrophysics Data System (ADS)

    Hofmann, David J.; Butler, James H.; Tans, Pieter P.

    Carbon dioxide is increasing in the atmosphere and is of considerable concern in global climate change because of its greenhouse gas warming potential. The rate of increase has accelerated since measurements began at Mauna Loa Observatory in 1958 where carbon dioxide increased from less than 1 part per million per year (ppm yr -1) prior to 1970 to more than 2 ppm yr -1 in recent years. Here we show that the anthropogenic component (atmospheric value reduced by the pre-industrial value of 280 ppm) of atmospheric carbon dioxide has been increasing exponentially with a doubling time of about 30 years since the beginning of the industrial revolution (˜1800). Even during the 1970s, when fossil fuel emissions dropped sharply in response to the "oil crisis" of 1973, the anthropogenic atmospheric carbon dioxide level continued increasing exponentially at Mauna Loa Observatory. Since the growth rate (time derivative) of an exponential has the same characteristic lifetime as the function itself, the carbon dioxide growth rate is also doubling at the same rate. This explains the observation that the linear growth rate of carbon dioxide has more than doubled in the past 40 years. The accelerating growth rate is simply the outcome of exponential growth in carbon dioxide with a nearly constant doubling time of about 30 years (about 2%/yr) and appears to have tracked human population since the pre-industrial era.

  8. New developments using carbon dioxide as a solvent: Monolayers and nanocomposites. 1. Reactions of organosilanes with oxidized silicon surfaces in carbon dioxide. 2. Polymer/polymer nanocomposites synthesized in carbon dioxide

    NASA Astrophysics Data System (ADS)

    Cao, Chuntao

    The aim of this research was to explore new directions for carbon dioxide. The first project emphasized silyl monolayer synthesis. Silylation reactions were performed in both liquid and supercritical carbon dioxide. Different monofunctional organosilanes reacted with silica surfaces, forming covalently attached monolayers. These monolayers were characterized using contact angle measurements, X-ray photoelectron spectroscopy, and ellipsometry. Reaction kinetics were established, and compared with silylations in organic solvents. The reaction rate in CO2 is higher than that in conventional solvents while the final coverage is slightly lower than the optimized conditions for conventional solvents. Other multi-functional silanes were also studied. The silylation of nanoporous silica surfaces showed bonding densities almost as high as the maximum value reported in literature for small-pore substrates. Overall, CO2 is a good solvent for silylations on silica surfaces. The second project was to synthesize polymer/polymer nanocomposites using a CO2-assisted templating method. Semicrystalline polymers are composed of tens-of-nanometer thick crystalline lamellae and an amorphous matrix. CO2 normally swells only the amorphous and interlamellar regions. The goal of this research was to selectively bring monomers to the amorphous and interlamellar regions with the help of CO2. In situ polymerization and precipitation fixes the structure, replicating the nano-structure of the semicrystalline polymer substrate. Ring-opening metathesis polymerization was performed inside of CO2-swollen poly(4-methyl-1-pentene) (PMP) of high crystallinity. Several polymer/polymer nanocomposites were successfully produced using this method. They were characterized by a variety of techniques, such as transmission electron microscopy (TEM), differential scanning calorimetry (DSC), thermal gravimetric analysis (TGA) and wide angle X-ray diffraction (WAXD). Infrared studies and TEM indicated that one type of composite, polynorbomene/PMP, had a gradient distribution of polynorbornene inside of the PMP matrix. Another composite, polyoctenamer/PMP prepared by cis-cyclooctene polymerization, exhibited very interesting mechanical properties. The poly(dicyclopentadiene)/PMP composites are unique nanometer-scale blends of a highly crosslinked thermoset with a thermoplastic polymer.

  9. Atmospheric carbon mineralization in an industrial-scale chrysotile mining waste pile.

    PubMed

    Nowamooz, Ali; Dupuis, J Christian; Beaudoin, Georges; Molson, John; Lemieux, Jean-Michel; Horswill, Micha; Fortier, Richard; Larachi, Faïçal; Maldague, Xavier; Constantin, Marc; Duchesne, Josee; Therrien, René

    2018-06-12

    Magnesium rich minerals that are abundant in ultramafic mining waste have the potential to be used as a safe and permanent sequestration solution for carbon dioxide (CO2). Our understanding of thermo-hydro-chemical regimes that govern this reaction at an industrial scale, however, has remained an important challenge to its widespread implementation. Through a year-long monitoring experiment performed at a 110Mt chrysotile waste pile, we have documented the existence of two distinct thermo-hydro-chemical regimes that control the ingress of CO2 and the subsequent mineral carbonation of the waste. The experimental results are supported by coupled free-air/porous media numerical flow and transport model that provides insights into optimization strategies to increase the efficiency of mineral sequestration at an industrial-scale. Although functioning passively under less than optimal conditions compared to lab-scale experiments, the 110Mt Thetford Mines pile is nevertheless estimated to be sequestering up to 100 tonnes of CO2 per year, with a potential total carbon capture capacity under optimal conditions of 3 Mt. Yearly, over 100 Mt of ultramafic mine waste suitable for mineral carbonation are generated by the global mining industry. Our results show that this waste material could become a safe and permanent carbon sink for diffuse sources of CO2.

  10. Thickness Map of Buried Carbon-Dioxide Deposit

    NASA Image and Video Library

    2011-04-21

    NASA Mars Reconnaissance Orbiter color-codes thickness estimates in a newly found, buried deposit of frozen carbon dioxide, dry ice, near the south pole of Mars contains ~30 times more carbon dioxide than previously estimated to be frozen near the pole.

  11. Organic syntheses employing supercritical carbon dioxide as a reaction solvent

    NASA Technical Reports Server (NTRS)

    Barstow, Leon E. (Inventor); Ward, Glen D. (Inventor); Bier, Milan (Inventor)

    1991-01-01

    Chemical reactions are readily carried out using supercritical carbon dioxide as the reaction medium. Supercritical carbon dioxide is of special value as a reaction medium in reactions for synthesizing polypeptides, for sequencing polypeptides, or for amino acid analysis.

  12. Organic syntheses employing supercritical carbon dioxide as a reaction solvent

    NASA Technical Reports Server (NTRS)

    Barstow, Leon E. (Inventor); Ward, Glen D. (Inventor); Bier, Milan (Inventor)

    1993-01-01

    Chemical reactions are readily carried out using supercritical carbon dioxide as the reaction medium. Supercritical carbon dioxide is of special value as a reaction medium in reactions for synthesizing polypeptides, for sequencing polypeptides, or for amino acid analysis.

  13. Dry Air Cooler Modeling for Supercritical Carbon Dioxide Brayton Cycle Analysis

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Moisseytsev, A.; Sienicki, J. J.; Lv, Q.

    Modeling for commercially available and cost effective dry air coolers such as those manufactured by Harsco Industries has been implemented in the Argonne National Laboratory Plant Dynamics Code for system level dynamic analysis of supercritical carbon dioxide (sCO 2) Brayton cycles. The modeling can now be utilized to optimize and simulate sCO 2 Brayton cycles with dry air cooling whereby heat is rejected directly to the atmospheric heat sink without the need for cooling towers that require makeup water for evaporative losses. It has sometimes been stated that a benefit of the sCO 2 Brayton cycle is that it enablesmore » dry air cooling implying that the Rankine steam cycle does not. A preliminary and simple examination of a Rankine superheated steam cycle and an air-cooled condenser indicates that dry air cooling can be utilized with both cycles provided that the cycle conditions are selected appropriately« less

  14. [Life support of the Mars exploration crew. Control of a zeolite system for carbon dioxide removal from space cabin air within a closed air regeneration cycle].

    PubMed

    Chekov, Iu F

    2009-01-01

    The author describes a zeolite system for carbon dioxide removal integrated into a closed air regeneration cycle aboard spacecraft. The continuous operation of a double-adsorbent regeneration system with pCO2-dependable productivity is maintained through programmable setting of adsorption (desorption) semicycle time. The optimal system regulation curve is presented within the space of statistical performance family obtained in quasi-steady operating modes with controlled parameters of the recurrent adsorption-desorption cycle. The automatically changing system productivity ensures continuous intake of concentrated CO2. Control of the adsorption-desorption process is based on calculation of the differential adsorption (desorption) heat from gradient of adsorbent and test inert substance temperatures. The adaptive algorithm of digital control is implemented through the standard spacecraft interface with the board computer system and programmable microprocessor-based controllers.

  15. Preparation and characterization of novel carbon dioxide adsorbents based on polyethylenimine-modified Halloysite nanotubes.

    PubMed

    Cai, Haohao; Bao, Feng; Gao, Jie; Chen, Tao; Wang, Si; Ma, Rui

    2015-01-01

    New nano-sized carbon dioxide (CO2) adsorbents based on Halloysite nanotubes impregnated with polyethylenimine (PEI) were designed and synthesized, which were excellent adsorbents for the capture of CO2 at room temperature and had relatively high CO2 adsorption capacity. The prepared adsorbents were characterized by various techniques such as Fourier transform infrared spectrometry, gel permeation chromatography, dynamic light scattering, thermogravimetry, thermogravimetry-Fourier transform-infrared spectrometry, scanning electron microscopy and transmission electron microscopy. The adsorption characteristics and capacity were studied at room temperature, the highest CO2 adsorption capacity of 156.6 mg/g-PEI was obtained and the optimal adsorption capacity can reach a maximum value of 54.8 mg/g-adsorbent. The experiment indicated that this kind of adsorbent has a high stability at 80°C and PEI-impregnated adsorbents showed good reversibility and stability during cyclic adsorption-regeneration tests.

  16. Selective Formation of Trimethylene Carbonate (TMC): Atmospheric Pressure Carbon Dioxide Utilization

    PubMed Central

    Buckley, Benjamin R; Patel, Anish P; Wijayantha, K G Upul

    2015-01-01

    Carbon dioxide utilisation (CDU) is currently gaining increased interest due to the abundance of CO2 and its possible application as a C1 building block. We herein report the first example of atmospheric pressure carbon dioxide incorporation into oxetane to selectively form trimethylene carbonate (TMC), which is a significant challenge as TMC is thermodynamically less favoured than its corresponding co-polymer. PMID:26213485

  17. Selective Formation of Trimethylene Carbonate (TMC): Atmospheric Pressure Carbon Dioxide Utilization.

    PubMed

    Buckley, Benjamin R; Patel, Anish P; Wijayantha, K G Upul

    2015-01-01

    Carbon dioxide utilisation (CDU) is currently gaining increased interest due to the abundance of CO 2 and its possible application as a C 1 building block. We herein report the first example of atmospheric pressure carbon dioxide incorporation into oxetane to selectively form trimethylene carbonate (TMC), which is a significant challenge as TMC is thermodynamically less favoured than its corresponding co-polymer.

  18. Carbon-13 and proton nuclear magnetic resonance analysis of shale-derived refinery products and jet fuels and of experimental referee broadened-specification jet fuels

    NASA Technical Reports Server (NTRS)

    Dalling, D. K.; Bailey, B. K.; Pugmire, R. J.

    1984-01-01

    A proton and carbon-13 nuclear magnetic resonance (NMR) study was conducted of Ashland shale oil refinery products, experimental referee broadened-specification jet fuels, and of related isoprenoid model compounds. Supercritical fluid chromatography techniques using carbon dioxide were developed on a preparative scale, so that samples could be quantitatively separated into saturates and aromatic fractions for study by NMR. An optimized average parameter treatment was developed, and the NMR results were analyzed in terms of the resulting average parameters; formulation of model mixtures was demonstrated. Application of novel spectroscopic techniques to fuel samples was investigated.

  19. The causal nexus between carbon dioxide emissions and agricultural ecosystem-an econometric approach.

    PubMed

    Asumadu-Sarkodie, Samuel; Owusu, Phebe Asantewaa

    2017-01-01

    Achieving a long-term food security and preventing hunger include a better nutrition through sustainable systems of production, distribution, and consumption. Nonetheless, the quest for an alternative to increasing global food supply to meet the growing demand has led to the use of poor agricultural practices that promote climate change. Given the contribution of the agricultural ecosystem towards greenhouse gas (GHG) emissions, this study investigated the causal nexus between carbon dioxide emissions and agricultural ecosystem by employing a data spanning from 1961 to 2012. Evidence from long-run elasticity shows that a 1 % increase in the area of rice paddy harvested will increase carbon dioxide emissions by 1.49 %, a 1 % increase in biomass-burned crop residues will increase carbon dioxide emissions by 1.00 %, a 1 % increase in cereal production will increase carbon dioxide emissions by 1.38 %, and a 1 % increase in agricultural machinery will decrease carbon dioxide emissions by 0.09 % in the long run. There was a bidirectional causality between carbon dioxide emissions, cereal production, and biomass-burned crop residues. The Granger causality shows that the agricultural ecosystem in Ghana is sensitive to climate change vulnerability.

  20. Use of natural gas, methanol, and ethanol fuel emulsions as environmentally friendly energy carriers for mobile heat power plants

    NASA Astrophysics Data System (ADS)

    Likhanov, V. A.; Lopatin, O. P.

    2017-12-01

    The need for using environmentally friendly energy carriers for mobile heat power plants (HPPs) is grounded. Ecologically friendly sources of energy, such as natural gas as well as renewable methyl and ethyl alcohols, are investigated. In order to develop, determine, and optimize the composition of environmentally friendly energy carriers for an HPP, the latter has been tested when working on diesel fuel (DF), compressed natural gas (CNG), and methanol and ethanol fuel emulsions (MFE, EFE). It has been experimentally established that, for the application of environmentally friendly energy carriers for a 4Ch 11.0/12.5 diesel engine of a mobile fuel and power plant, it is necessary to maintain the following ratio of components when working on CNG: 80% gas and 20% DF primer portion. When working on an alcohol mixture, emulsions of the following composition were used: 25% alcohol (methanol or ethanol), 0.5% detergent-dispersant additive succinimide C-5A, 7% water, and 67.5% DF. When this diesel passed from oil DF to environmentally friendly energy sources, it allowed for the reduction of the content of exhaust gases (EG) (1) when working on CNG with recirculation of exhaust gases (EGR) (recirculation was used to eliminate the increased amount of nitric oxides by using CNG): carbon black by 5.8 times, carbon dioxide by 45.9%, and carbon monoxide by 23.8%; (2) when working on MFE: carbon black by 6.4 times, nitrogen oxides by 29.6%, carbon dioxide by 10.1%, and carbon oxide by 47.6%; (3) when working on EFE: carbon black by 4.8 times; nitrogen oxides by 40.3%, carbon dioxide by 26.6%, and carbon monoxide by 28.6%. The prospects of use of environmentally friendly energy carriers in diesels of mobile HPPs, such as natural gas, ethanol, and methanol, has been determined.

  1. Computer simulation for optimizing windbreak placement to save energy for heating and cooling buildings

    Treesearch

    Gordon M. Heisler

    1991-01-01

    Saving energy has recently acquired new importance because of increased concern for dwindling fossil fuel supplies and for the problem of carbon dioxide contributions to global climate change. Many studies have indicated that windbreaks have the ability to save energy for heating buildings. Suggested savings have ranged up 40 percent; though more commonly savings of...

  2. Methods and systems for producing syngas

    DOEpatents

    Hawkes, Grant L; O& #x27; Brien, James E; Stoots, Carl M; Herring, J. Stephen; McKellar, Michael G; Wood, Richard A; Carrington, Robert A; Boardman, Richard D

    2013-02-05

    Methods and systems are provided for producing syngas utilizing heat from thermochemical conversion of a carbonaceous fuel to support decomposition of at least one of water and carbon dioxide using one or more solid-oxide electrolysis cells. Simultaneous decomposition of carbon dioxide and water or steam by one or more solid-oxide electrolysis cells may be employed to produce hydrogen and carbon monoxide. A portion of oxygen produced from at least one of water and carbon dioxide using one or more solid-oxide electrolysis cells is fed at a controlled flow rate in a gasifier or combustor to oxidize the carbonaceous fuel to control the carbon dioxide to carbon monoxide ratio produced.

  3. Supercritical Carbon Dioxide Extraction of Flavonoids from Pomelo (Citrus grandis (L.) Osbeck) Peel and Their Antioxidant Activity

    PubMed Central

    He, Jin-Zhe; Shao, Ping; Liu, Jian-Hua; Ru, Qiao-Mei

    2012-01-01

    Supercritical carbon dioxide (SC-CO2) extraction of flavonoids from pomelo (Citrus grandis (L.) Osbeck) peel and their antioxidant activity were investigated. Box-Behnken design combined with response surface methodology was employed to maximize the extraction yield of flavonoids. Correlation analysis of the mathematical-regression model indicated that a quadratic polynomial model could be used to optimize the SC-CO2 extraction of flavonoids. The optimal conditions for obtaining the highest extraction yield of flavonoids from pomelo peel were a temperature of 80 °C, a pressure of 39 MPa and a static extraction time of 49 min in the presence of 85% ethanol as modifier. Under these conditions, the experimental yield was 2.37%, which matched positively with the value predicted by the model. Furthermore, flavonoids obtained by SC-CO2 extraction showed a higher scavenging activity on hydroxyl, 1,1-diphenyl-2-picrylhydrazyl (DPPH) and 2,2′-azino-bis(3-ethylbenzthiazoline-6-sulphonic acid) (ABTS) radicals than those obtained by conventional solvent extraction (CSE). Therefore, SC-CO2 extraction can be considered as a suitable technique for the obtainment of flavonoids from pomelo peel. PMID:23202938

  4. Ocean Fertilization for Sequestration of Carbon Dioxide from the Atmosphere

    NASA Astrophysics Data System (ADS)

    Boyd, Philip W.

    The ocean is a major sink for both preindustrial and anthropogenic carbon dioxide. Both physically and biogeochemically driven pumps, termed the solubility and biological pump, respectively Fig.5.1) are responsible for the majority of carbon sequestration in the ocean's interior [1]. The solubility pump relies on ocean circulation - specifically the impact of cooling of the upper ocean at high latitudes both enhances the solubility of carbon dioxide and the density of the waters which sink to great depth (the so-called deepwater formation) and thereby sequester carbon in the form of dissolved inorganic carbon (Fig.5.1). The biological pump is driven by the availability of preformed plant macronutrients such as nitrate or phosphate which are taken up by phytoplankton during photosynthetic carbon fixation. A small but significant proportion of this fixed carbon sinks into the ocean's interior in the form of settling particles, and in order to maintain equilibrium carbon dioxide from the atmosphere is transferred across the air-sea interface into the ocean (the so-called carbon drawdown) thereby decreasing atmospheric carbon dioxide (Fig.5.1).Fig.5.1

  5. Optimal design of microtube recuperators for an indirect supercritical carbon dioxide recompression closed Brayton cycle

    DOE PAGES

    Jiang, Yuan; Liese, Eric; Zitney, Stephen E.; ...

    2018-02-25

    This paper presents a baseline design and optimization approach developed in Aspen Custom Modeler (ACM) for microtube shell-and-tube exchangers (MSTEs) used for high- and low-temperature recuperation in a 10 MWe indirect supercritical carbon dioxide (sCO 2) recompression closed Brayton cycle (RCBC). The MSTE-type recuperators are designed using one-dimensional models with thermal-hydraulic correlations appropriate for sCO 2 and properties models that capture considerable nonlinear changes in CO 2 properties near the critical and pseudo-critical points. Using the successive quadratic programming (SQP) algorithm in ACM, optimal recuperator designs are obtained for either custom or industry-standard microtubes considering constraints based on current advancedmore » manufacturing techniques. The three decision variables are the number of tubes, tube pitch-to-diameter ratio, and tube diameter. Five different objective functions based on different key design measures are considered: minimization of total heat transfer area, heat exchanger volume, metal weight, thermal residence time, and maximization of compactness. Sensitivities studies indicate the constraint on the maximum number of tubes per shell does affect the number of parallel heat exchanger trains but not the tube selection, total number of tubes, tube length and other key design measures in the final optimal design when considering industry-standard tubes. In this study, the optimally designed high- and low-temperature recuperators have 47,000 3/32 inch tubes and 63,000 1/16 inch tubes, respectively. In addition, sensitivities to the design temperature approach and maximum allowable pressure drop are studied, since these specifications significantly impact the optimal design of the recuperators as well as the thermal efficiency and the economic performance of the entire sCO 2 Brayton cycle.« less

  6. Optimal design of microtube recuperators for an indirect supercritical carbon dioxide recompression closed Brayton cycle

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Jiang, Yuan; Liese, Eric; Zitney, Stephen E.

    This paper presents a baseline design and optimization approach developed in Aspen Custom Modeler (ACM) for microtube shell-and-tube exchangers (MSTEs) used for high- and low-temperature recuperation in a 10 MWe indirect supercritical carbon dioxide (sCO 2) recompression closed Brayton cycle (RCBC). The MSTE-type recuperators are designed using one-dimensional models with thermal-hydraulic correlations appropriate for sCO 2 and properties models that capture considerable nonlinear changes in CO 2 properties near the critical and pseudo-critical points. Using the successive quadratic programming (SQP) algorithm in ACM, optimal recuperator designs are obtained for either custom or industry-standard microtubes considering constraints based on current advancedmore » manufacturing techniques. The three decision variables are the number of tubes, tube pitch-to-diameter ratio, and tube diameter. Five different objective functions based on different key design measures are considered: minimization of total heat transfer area, heat exchanger volume, metal weight, thermal residence time, and maximization of compactness. Sensitivities studies indicate the constraint on the maximum number of tubes per shell does affect the number of parallel heat exchanger trains but not the tube selection, total number of tubes, tube length and other key design measures in the final optimal design when considering industry-standard tubes. In this study, the optimally designed high- and low-temperature recuperators have 47,000 3/32 inch tubes and 63,000 1/16 inch tubes, respectively. In addition, sensitivities to the design temperature approach and maximum allowable pressure drop are studied, since these specifications significantly impact the optimal design of the recuperators as well as the thermal efficiency and the economic performance of the entire sCO 2 Brayton cycle.« less

  7. Open-cycle magnetohydrodynamic power plant with CO.sub.2 recycling

    DOEpatents

    Berry, Gregory F.

    1991-01-01

    A method of converting the chemical energy of fossil fuel to electrical and mechanical energy with a MHD generator. The fossil fuel is mixed with preheated oxygen and carbon dioxide and a conducting seed of potassium carbonate to form a combustive and electrically conductive mixture which is burned in a combustion chamber. The burned combustion mixture is passed through a MHD generator to generate electrical energy. The burned combustion mixture is passed through a diffuser to restore the mixture approximately to atmospheric pressure, leaving a spent combustion mixture which is used to heat oxygen from an air separation plant and recycled carbon dioxide for combustion in a high temperature oxygen preheater and for heating water/steam for producing superheated steam. Relatively pure carbon dioxide is separated from the spent combustion mixture for further purification or for exhaust, while the remainder of the carbon dioxide is recycled from the spent combustion mixture to a carbon dioxide purification plant for removal of water and any nitrous oxides present, leaving a greater than 98% pure carbon dioxide. A portion of the greater then 98% pure carbon dioxide stream is recovered and the remainder is recycled to combine with the oxygen for preheating and combination with the fossil fuel to form a combustion mixture.

  8. Method of determining pH by the alkaline absorption of carbon dioxide

    DOEpatents

    Hobbs, David T.

    1992-01-01

    A method for measuring the concentration of hydroxides in alkaline solutions in a remote location using the tendency of hydroxides to absorb carbon dioxide. The method includes the passing of carbon dioxide over the surface of an alkaline solution in a remote tank before and after measurements of the carbon dioxide solution. A comparison of the measurements yields the absorption fraction from which the hydroxide concentration can be calculated using a correlation of hydroxide or pH to absorption fraction.

  9. Supercritical carbon dioxide: a solvent like no other

    PubMed Central

    Peach, Jocelyn

    2014-01-01

    Summary Supercritical carbon dioxide (scCO2) could be one aspect of a significant and necessary movement towards green chemistry, being a potential replacement for volatile organic compounds (VOCs). Unfortunately, carbon dioxide has a notoriously poor solubilising power and is famously difficult to handle. This review examines attempts and breakthroughs in enhancing the physicochemical properties of carbon dioxide, focusing primarily on factors that impact solubility of polar and ionic species and attempts to enhance scCO2 viscosity. PMID:25246947

  10. Numerical simulation of injection process of warm carbon dioxide into layer saturated with methane and its hydrate

    NASA Astrophysics Data System (ADS)

    Khasanov, M. K.; Stolpovsky, M. V.; Gimaltdinov, I. K.

    2018-05-01

    In this article, in a flat-one-dimensional approximation, a mathematical model is presented for injecting warm carbon dioxide into a methane hydrate formation of finite length. It is established that the model of formation of hydrate of carbon dioxide in the absence of an area saturated with methane and water, under certain parameters, leads to thermodynamic contradiction. The mathematical model of carbon dioxide injection with formation of the region saturated with methane and water is constructed.

  11. Environment and economic risk: An analysis of carbon emission market and portfolio management.

    PubMed

    Luo, Cuicui; Wu, Desheng

    2016-08-01

    Climate change has been one of the biggest and most controversial environmental issues of our times. It affects the global economy, environment and human health. Many researchers find that carbon dioxide (CO2) has contributed the most to climate change between 1750 and 2005. In this study, the orthogonal GARCH (OGARCH) model is applied to examine the time-varying correlations in European CO2 allowance, crude oil and stock markets in US, Europe and China during the Protocol's first commitment period. The results show that the correlations between EUA carbon spot price and the equity markets are higher and more volatile in US and Europe than in China. Then the optimal portfolios consisting these five time series are selected by Mean-Variance and Mean-CVAR models. It shows that the optimal portfolio selected by MV-OGARCH model has the best performance. Copyright © 2016 Elsevier Inc. All rights reserved.

  12. Optimizing the withdrawal speed using dip coating for optical sensor

    NASA Astrophysics Data System (ADS)

    Samat, S. F. A.; Sarah, M. S. P.; Idros, M. Faizol Md; Rusop, M.

    2018-05-01

    The processing route of sol-gel has been used for many productions of thin film using metal oxide such as titanium dioxide, zinc oxide, carbon dioxide and so on. For this research the thin film phase was studied has high transmittance using dip coating technique with different withdrawal speed for optical sensing. The result obtained from optical transmittance spectra that transmits at 30nm and bend at 350nm to 800nm was in the visible light wavelength range. From the data, the withdrawal speed was low at 5s and 10s could give the highest transmittance which were 90.41% and 87.91% respectively.

  13. Reduction of Carbon Dioxide by a Molybdenum-Containing Formate Dehydrogenase: A Kinetic and Mechanistic Study.

    PubMed

    Maia, Luisa B; Fonseca, Luis; Moura, Isabel; Moura, José J G

    2016-07-20

    Carbon dioxide accumulation is a major concern for the ecosystems, but its abundance and low cost make it an interesting source for the production of chemical feedstocks and fuels. However, the thermodynamic and kinetic stability of the carbon dioxide molecule makes its activation a challenging task. Studying the chemistry used by nature to functionalize carbon dioxide should be helpful for the development of new efficient (bio)catalysts for atmospheric carbon dioxide utilization. In this work, the ability of Desulfovibrio desulfuricans formate dehydrogenase (Dd FDH) to reduce carbon dioxide was kinetically and mechanistically characterized. The Dd FDH is suggested to be purified in an inactive form that has to be activated through a reduction-dependent mechanism. A kinetic model of a hysteretic enzyme is proposed to interpret and predict the progress curves of the Dd FDH-catalyzed reactions (initial lag phase and subsequent faster phase). Once activated, Dd FDH is able to efficiently catalyze, not only the formate oxidation (kcat of 543 s(-1), Km of 57.1 μM), but also the carbon dioxide reduction (kcat of 46.6 s(-1), Km of 15.7 μM), in an overall reaction that is thermodynamically and kinetically reversible. Noteworthy, both Dd FDH-catalyzed formate oxidation and carbon dioxide reduction are completely inactivated by cyanide. Current FDH reaction mechanistic proposals are discussed and a different mechanism is here suggested: formate oxidation and carbon dioxide reduction are proposed to proceed through hydride transfer and the sulfo group of the oxidized and reduced molybdenum center, Mo(6+)═S and Mo(4+)-SH, are suggested to be the direct hydride acceptor and donor, respectively.

  14. Green hydrophilic interaction chromatography using ethanol-water-carbon dioxide mixtures.

    PubMed

    Pereira, Alberto dos Santos; Girón, Ana Jiménez; Admasu, Engdawork; Sandra, Pat

    2010-03-01

    In hydrophilic interaction chromatography (HILIC), best results are obtained with high concentrations of acetonitrile. In the framework of green chromatography, different concentrations of carbon dioxide were added to the mobile phases acetonitrile-water and ethanol-water and the impact on retention and separation in HILIC using bare silica as stationary phase was explored. The features of HILIC using enhanced-fluidity mobile phases are illustrated with the analysis of the nucleobases and a mixture containing the nucleobases and cortisol, flurbiprofen, theophylline and caffeine. For both organic constituents, the elution window is widened in function of the carbon dioxide concentration and selectivity changes. At high concentrations of carbon dioxide in ethanol, separations were similar to those obtained with acetonitrile without carbon dioxide addition.

  15. Membrane loop process for separating carbon dioxide for use in gaseous form from flue gas

    DOEpatents

    Wijmans, Johannes G; Baker, Richard W; Merkel, Timothy C

    2014-10-07

    The invention is a process involving membrane-based gas separation for separating and recovering carbon dioxide emissions from combustion processes in partially concentrated form, and then transporting the carbon dioxide and using or storing it in a confined manner without concentrating it to high purity. The process of the invention involves building up the concentration of carbon dioxide in a gas flow loop between the combustion step and a membrane separation step. A portion of the carbon dioxide-enriched gas can then be withdrawn from this loop and transported, without the need to liquefy the gas or otherwise create a high-purity stream, to a destination where it is used or confined, preferably in an environmentally benign manner.

  16. Carbon capture by sorption-enhanced water-gas shift reaction process using hydrotalcite-based material

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    van Selow, E.R.; Cobden, P.D.; Verbraeken, P.A.

    2009-05-15

    A novel route for precombustion decarbonization is the sorption-enhanced water-gas shift (SEWGS) process. In this process carbon dioxide is removed from a synthesis gas at elevated temperature by adsorption. Simultaneously, carbon monoxide is converted to carbon dioxide by the water-gas shift reaction. The periodic adsorption and desorption of carbon dioxide is induced by a pressure swing cycle, and the cyclic capacity can be amplified by purging with steam. From previous studies is it known that for SEWGS applications, hydrotalcite-based materials are particularly attractive as sorbent, and commercial high-temperature shift catalysts can be used for the conversion of carbon monoxide. Tabletsmore » of a potassium promoted hydrotalcite-based material are characterized in both breakthrough and cyclic experiments in a 2 m tall fixed-bed reactor. When exposed to a mixture of carbon dioxide, steam, and nitrogen at 400{sup o}C, the material shows a breakthrough capacity of 1.4 mmol/g. In subsequent experiments the material was mixed with tablets of promoted iron-chromium shift catalyst and exposed to a mixture of carbon dioxide, carbon monoxide, steam, hydrogen, and nitrogen. It is demonstrated that carbon monoxide conversion can be enhanced to 100% in the presence of a carbon dioxide sorbent. At breakthrough, carbon monoxide and carbon dioxide simultaneously appear at the end of the bed. During more than 300 cycles of adsorption/reaction and desorption, the capture rate, and carbon monoxide conversion are confirmed to be stable. Two different cycle types are investigated: one cycle with a CO{sub 2} rinse step and one cycle with a steam rinse step. The performance of both SEWGS cycles are discussed.« less

  17. Fatty acid composition and antioxidant activity of tea (Camellia sinensis L.) seed oil extracted by optimized supercritical carbon dioxide.

    PubMed

    Wang, Yuefei; Sun, Da; Chen, Hao; Qian, Lisheng; Xu, Ping

    2011-01-01

    Seeds are another product in addition to leaves (raw materials for teas) of tea (Camellia sinensis L.) plant. The great increase of tea consumption in recent years raises the challenge of finding commercial applications for tea seeds. In the present study, supercritical carbon dioxide (SC-CO(2)) extraction edible oil from tea seed was carried out, response surface methodology (RSM) was used to optimize processing parameters including time (20-90 min), temperature (35-45 °C) and pressure (50-90 MPa). The fatty acid composition and antioxidant activity of the extracted oil was also investigated. The highest yield of oil (29.2 ± 0.6%) was obtained under optimal SC-CO(2) extraction conditions (45 °C, 89.7 min and 32 MPa, respectively), which was significantly higher (p < 0.05) than that (25.3 ± 1.0%) given by Soxhlet extraction. Meanwhile, tea seed oil extracted by SC-CO(2) contained approximately 80% unsaturated fatty acids and showed a much stronger scavenging ability on the DPPH radical than that extracted by Soxhlet. SC-CO(2) is a promising alternative for efficient extraction of edible oil from tea seed. Moreover, tea seed oil extracted by SC-CO(2) is highly edible and has good antioxidant activity, and therefore may play a potential role as a health-promoting food resource in human diets.

  18. A multi-objective optimization approach for the selection of working fluids of geothermal facilities: Economic, environmental and social aspects.

    PubMed

    Martínez-Gomez, Juan; Peña-Lamas, Javier; Martín, Mariano; Ponce-Ortega, José María

    2017-12-01

    The selection of the working fluid for Organic Rankine Cycles has traditionally been addressed from systematic heuristic methods, which perform a characterization and prior selection considering mainly one objective, thus avoiding a selection considering simultaneously the objectives related to sustainability and safety. The objective of this work is to propose a methodology for the optimal selection of the working fluid for Organic Rankine Cycles. The model is presented as a multi-objective approach, which simultaneously considers the economic, environmental and safety aspects. The economic objective function considers the profit obtained by selling the energy produced. Safety was evaluated in terms of individual risk for each of the components of the Organic Rankine Cycles and it was formulated as a function of the operating conditions and hazardous properties of each working fluid. The environmental function is based on carbon dioxide emissions, considering carbon dioxide mitigation, emission due to the use of cooling water as well emissions due material release. The methodology was applied to the case of geothermal facilities to select the optimal working fluid although it can be extended to waste heat recovery. The results show that the hydrocarbons represent better solutions, thus among a list of 24 working fluids, toluene is selected as the best fluid. Copyright © 2017 Elsevier Ltd. All rights reserved.

  19. Fatty Acid Composition and Antioxidant Activity of Tea (Camellia sinensis L.) Seed Oil Extracted by Optimized Supercritical Carbon Dioxide

    PubMed Central

    Wang, Yuefei; Sun, Da; Chen, Hao; Qian, Lisheng; Xu, Ping

    2011-01-01

    Seeds are another product in addition to leaves (raw materials for teas) of tea (Camellia sinensis L.) plant. The great increase of tea consumption in recent years raises the challenge of finding commercial applications for tea seeds. In the present study, supercritical carbon dioxide (SC-CO2) extraction edible oil from tea seed was carried out, response surface methodology (RSM) was used to optimize processing parameters including time (20–90 min), temperature (35–45 °C) and pressure (50–90 MPa). The fatty acid composition and antioxidant activity of the extracted oil was also investigated. The highest yield of oil (29.2 ± 0.6%) was obtained under optimal SC-CO2 extraction conditions (45 °C, 89.7 min and 32 MPa, respectively), which was significantly higher (p < 0.05) than that (25.3 ± 1.0%) given by Soxhlet extraction. Meanwhile, tea seed oil extracted by SC-CO2 contained approximately 80% unsaturated fatty acids and showed a much stronger scavenging ability on the DPPH radical than that extracted by Soxhlet. SC-CO2 is a promising alternative for efficient extraction of edible oil from tea seed. Moreover, tea seed oil extracted by SC-CO2 is highly edible and has good antioxidant activity, and therefore may play a potential role as a health-promoting food resource in human diets. PMID:22174626

  20. 49 CFR 179.102-1 - Carbon dioxide, refrigerated liquid.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... HAZARDOUS MATERIALS SAFETY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) SPECIFICATIONS FOR TANK CARS Specifications for Pressure Tank Car Tanks (Classes DOT-105, 109, 112, 114 and 120) § 179.102-1 Carbon dioxide, refrigerated liquid. (a) Tank cars used to transport carbon dioxide, refrigerated liquid...

  1. 49 CFR 179.102-1 - Carbon dioxide, refrigerated liquid.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... HAZARDOUS MATERIALS SAFETY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) SPECIFICATIONS FOR TANK CARS Specifications for Pressure Tank Car Tanks (Classes DOT-105, 109, 112, 114 and 120) § 179.102-1 Carbon dioxide, refrigerated liquid. (a) Tank cars used to transport carbon dioxide, refrigerated liquid...

  2. 49 CFR 179.102-1 - Carbon dioxide, refrigerated liquid.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... HAZARDOUS MATERIALS SAFETY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) SPECIFICATIONS FOR TANK CARS Specifications for Pressure Tank Car Tanks (Classes DOT-105, 109, 112, 114 and 120) § 179.102-1 Carbon dioxide, refrigerated liquid. (a) Tank cars used to transport carbon dioxide, refrigerated liquid...

  3. 46 CFR 193.15-35 - Enclosure openings.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... EQUIPMENT Carbon Dioxide Extinguishing Systems, Details § 193.15-35 Enclosure openings. (a) Where mechanical ventilation is provided for spaces which are protected by carbon dioxide extinguishing systems provisions... to that space. (b) Where natural ventilation is provided for spaces protected by a carbon dioxide...

  4. 46 CFR 76.15-30 - Alarms.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ..., DEPARTMENT OF HOMELAND SECURITY (CONTINUED) PASSENGER VESSELS FIRE PROTECTION EQUIPMENT Carbon Dioxide Extinguishing Systems, Details § 76.15-30 Alarms. (a) Spaces which are protected by a carbon dioxide... such spaces which will be automatically sounded when the carbon dioxide is admitted to the space. The...

  5. 46 CFR 76.15-30 - Alarms.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ..., DEPARTMENT OF HOMELAND SECURITY (CONTINUED) PASSENGER VESSELS FIRE PROTECTION EQUIPMENT Carbon Dioxide Extinguishing Systems, Details § 76.15-30 Alarms. (a) Spaces which are protected by a carbon dioxide... such spaces which will be automatically sounded when the carbon dioxide is admitted to the space. The...

  6. 40 CFR 86.1524 - Carbon dioxide analyzer calibration.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 20 2012-07-01 2012-07-01 false Carbon dioxide analyzer calibration. 86.1524 Section 86.1524 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Test Procedures § 86.1524 Carbon dioxide analyzer calibration. (a) The calibration requirements for the...

  7. 46 CFR 76.15-30 - Alarms.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ..., DEPARTMENT OF HOMELAND SECURITY (CONTINUED) PASSENGER VESSELS FIRE PROTECTION EQUIPMENT Carbon Dioxide Extinguishing Systems, Details § 76.15-30 Alarms. (a) Spaces which are protected by a carbon dioxide... such spaces which will be automatically sounded when the carbon dioxide is admitted to the space. The...

  8. 46 CFR 34.15-30 - Alarms-T/ALL.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... GUARD, DEPARTMENT OF HOMELAND SECURITY TANK VESSELS FIREFIGHTING EQUIPMENT Carbon Dioxide Extinguishing...) which are protected by a carbon dioxide extinguishing system and are normally accessible to persons on... the carbon dioxide is admitted to the space. The alarm shall be conspicuously and centrally located...

  9. 40 CFR 86.1524 - Carbon dioxide analyzer calibration.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 19 2014-07-01 2014-07-01 false Carbon dioxide analyzer calibration. 86.1524 Section 86.1524 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Procedures § 86.1524 Carbon dioxide analyzer calibration. (a) The calibration requirements for the dilute...

  10. 46 CFR 34.15-30 - Alarms-T/ALL.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... GUARD, DEPARTMENT OF HOMELAND SECURITY TANK VESSELS FIREFIGHTING EQUIPMENT Carbon Dioxide Extinguishing...) which are protected by a carbon dioxide extinguishing system and are normally accessible to persons on... the carbon dioxide is admitted to the space. The alarm shall be conspicuously and centrally located...

  11. 46 CFR 34.15-30 - Alarms-T/ALL.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... GUARD, DEPARTMENT OF HOMELAND SECURITY TANK VESSELS FIREFIGHTING EQUIPMENT Carbon Dioxide Extinguishing...) which are protected by a carbon dioxide extinguishing system and are normally accessible to persons on... the carbon dioxide is admitted to the space. The alarm shall be conspicuously and centrally located...

  12. 46 CFR 193.15-35 - Enclosure openings.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... EQUIPMENT Carbon Dioxide and Clean Agent Extinguishing Systems, Details § 193.15-35 Enclosure openings. (a) Where mechanical ventilation is provided for spaces which are protected by carbon dioxide extinguishing... carbon dioxide extinguishing system, provisions shall be made for easily and effectively closing off the...

  13. 46 CFR 76.15-30 - Alarms.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ..., DEPARTMENT OF HOMELAND SECURITY (CONTINUED) PASSENGER VESSELS FIRE PROTECTION EQUIPMENT Carbon Dioxide Extinguishing Systems, Details § 76.15-30 Alarms. (a) Spaces which are protected by a carbon dioxide... such spaces which will be automatically sounded when the carbon dioxide is admitted to the space. The...

  14. 46 CFR 193.15-35 - Enclosure openings.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... EQUIPMENT Carbon Dioxide and Clean Agent Extinguishing Systems, Details § 193.15-35 Enclosure openings. (a) Where mechanical ventilation is provided for spaces which are protected by carbon dioxide extinguishing... carbon dioxide extinguishing system, provisions shall be made for easily and effectively closing off the...

  15. 46 CFR 193.15-35 - Enclosure openings.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... EQUIPMENT Carbon Dioxide Extinguishing Systems, Details § 193.15-35 Enclosure openings. (a) Where mechanical ventilation is provided for spaces which are protected by carbon dioxide extinguishing systems provisions... to that space. (b) Where natural ventilation is provided for spaces protected by a carbon dioxide...

  16. The effect of carbon dioxide on the twinkling artifact in ultrasound imaging of kidney stones: A pilot study

    PubMed Central

    Simon, Julianna C.; Wang, Yak-Nam; Cunitz, Bryan W.; Thiel, Jeffrey; Starr, Frank; Liu, Ziyue; Bailey, Michael R.

    2016-01-01

    Bone demineralization, dehydration, and stasis put astronauts at an increased risk of forming kidney stones in space. The color-Doppler ultrasound “twinkling artifact”, which highlights kidney stones with color, can make stones readily detectable with ultrasound; however our previous results suggest twinkling is caused by microbubbles on the stone surface which could be affected by the elevated levels of carbon dioxide found on space vehicles. Four pigs were implanted with kidney stones and imaged with ultrasound while the anesthetic carrier gas oscillated between oxygen and air containing 0.8% carbon dioxide. Upon exposing pigs to 0.8% carbon dioxide, twinkling was significantly reduced after 9–25 minutes and recovered when the carrier gas returned to oxygen. These trends repeated when pigs were again exposed to 0.8% carbon dioxide followed by oxygen. The reduction of twinkling from exposure to elevated carbon dioxide may make kidney stone detection with twinkling difficult in current space vehicles. PMID:28190622

  17. Novel Concept of Frequency-Combs Interferometric Spectroscopy in the Mid-IR for Significantly Enhanced Detection of Explosives

    DTIC Science & Technology

    2015-12-01

    frequency combs. Ultrasensitive detection of methane, isotopic carbon dioxide, carbon monoxide, formaldehyde, acetylene, and ethylene was performed in...rmaldehyde, acetylene, and ethylene was perfo rmed in the spectral range 2.5- 5 11111 using intracav ity spectroscopy in broadband optical parametric osc...trace point detection of methane, carbon dioxide, isotopic (13C02) carbon dioxide, carbon monoxide, ethylene , acetylene, and formaldehyde and

  18. High performance hydrophobic solvent, carbon dioxide capture

    DOEpatents

    Nulwala, Hunaid; Luebke, David

    2017-05-09

    Methods and compositions useful, for example, for physical solvent carbon capture. A method comprising: contacting at least one first composition comprising carbon dioxide with at least one second composition to at least partially dissolve the carbon dioxide of the first composition in the second composition, wherein the second composition comprises at least one siloxane compound which is covalently modified with at least one non-siloxane group comprising at least one heteroatom. Polydimethylsiloxane (PDMS) materials and ethylene-glycol based materials have high carbon dioxide solubility but suffer from various problems. PDMS is hydrophobic but suffers from low selectivity. Ethylene-glycol based systems have good solubility and selectivity, but suffer from high affinity to water. Solvents were developed which keep the desired combinations of properties, and result in a simplified, overall process for carbon dioxide removal from a mixed gas stream.

  19. Herbivore responses to plants grown in enriched carbon dioxide atmospheres

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Lincoln, D.E.

    1990-05-01

    Our initial study of sagebrush and grasshopper responses to elevated and historical carbon dioxide atmospheres is complete and has been accepted for publication. The study on Biomass Allocation Patterns of Defoliated Sagebrush Grown Under Two Levels of Carbon Dioxide has completed and the manuscript has been submitted for publication. We have completed the study of plant growth under two nutrient and carbon dioxide regimes and grasshopper feeding responses. The study of a specialist feeding caterpillar, the cabbage butterfly, and a mustard hostplant has recently been completed. We were able to identify the principal allelochemicals of the mustard plants, butenyl andmore » pentenyl isothiocyanates, by combined gas chromatography and mass spectrometry. Measurement of these chemicals has been a critical component of this study since these compounds contain nitrogen and sulphur and act as a feeding stimulant to the caterpillar. This insect responds to elevated carbon dioxide by consuming more leaves and we can now say that this is not due to a change in the feeding stimulants. Reduced leaf protein content is a critical factor for even specialist feeding insect herbivores under elevated carbon dioxide conditions. The study on Grasshopper Population Responses to Enriched Carbon Dioxide Concentration is currently in progress at the Duke University Phytotron. We have changed hostplant species in order to complement the investigations of carbon dioxide effects on tallgrass prairie. Specifically, we are using big bluestem, Andropogon geradii, as the host plant to feed to the grasshoppers. This experiment will be completed in July 1990.« less

  20. Modeling carbon dioxide, pH, and un-ionized ammonia relationships in serial reuse systems

    USGS Publications Warehouse

    Colt, J.; Watten, B.; Rust, M.

    2009-01-01

    In serial reuse systems, excretion of metabolic carbon dioxide has a significant impact on ambient pH, carbon dioxide, and un-ionized ammonia concentrations. This impact depends strongly on alkalinity, water flow rate, feeding rate, and loss of carbon dioxide to the atmosphere. A reduction in pH from metabolic carbon dioxide can significantly reduce the un-ionized ammonia concentration and increase the carbon dioxide concentrations compared to those parameters computed from influent pH. The ability to accurately predict pH in serial reuse systems is critical to their design and effective operation. A trial and error solution to the alkalinity-pH system was used to estimate important water quality parameters in serial reuse systems. Transfer of oxygen and carbon dioxide across the air-water interface, at overflow weirs, and impacts of substrate-attached algae and suspended bacteria were modeled. Gas transfer at the weirs was much greater than transfer across the air-water boundary. This simulation model can rapidly estimate influent and effluent concentrations of dissolved oxygen, carbon dioxide, and un-ionized ammonia as a function of water temperature, elevation, water flow, and weir type. The accuracy of the estimates strongly depends on assumed pollutional loading rates and gas transfer at the weirs. The current simulation model is based on mean daily loading rates; the impacts of daily variation loading rates are discussed. Copies of the source code and executable program are available free of charge.

  1. Modeling Carbon Dioxide, pH and Un-Ionized Ammonia Relationships in Serial Reuse Systems

    USGS Publications Warehouse

    Watten, Barnaby J.; Rust, Michael; Colt, John

    2009-01-01

    In serial reuse systems, excretion of metabolic carbon dioxide has a significant impact on ambient pH, carbon dioxide, and un-ionized ammonia concentrations. This impact depends strongly on alkalinity, water flow rate, feeding rate, and loss of carbon dioxide to the atmosphere. A reduction in pH from metabolic carbon dioxide can significantly reduce the un-ionized ammonia concentration and increase the carbon dioxide concentrations compared to those parameters computed from influent pH. The ability to accurately predict pH in serial reuse systems is critical to their design and effective operation. A trial and error solution to the alkalinity–pH system was used to estimate important water quality parameters in serial reuse systems. Transfer of oxygen and carbon dioxide across the air–water interface, at overflow weirs, and impacts of substrate-attached algae and suspended bacteria were modeled. Gas transfer at the weirs was much greater than transfer across the air–water boundary. This simulation model can rapidly estimate influent and effluent concentrations of dissolved oxygen, carbon dioxide, and un-ionized ammonia as a function of water temperature, elevation, water flow, and weir type. The accuracy of the estimates strongly depends on assumed pollutional loading rates and gas transfer at the weirs. The current simulation model is based on mean daily loading rates; the impacts of daily variation loading rates are discussed. Copies of the source code and executable program are available free of charge.

  2. Reactions of Criegee Intermediates with Non-Water Greenhouse Gases: Implications for Metal Free Chemical Fixation of Carbon Dioxide.

    PubMed

    Kumar, Manoj; Francisco, Joseph S

    2017-09-07

    High-level theoretical calculations suggest that a Criegee intermediate preferably interacts with carbon dioxide compared to two other greenhouse gases, nitrous oxide and methane. The results also suggest that the interaction between Criegee intermediates and carbon dioxide involves a cycloaddition reaction, which results in the formation of a cyclic carbonate-type adduct with a barrier of 6.0-14.0 kcal/mol. These results are in contrast to a previous assumption that the reaction occurs barrierlessly. The subsequent decomposition of the cyclic adduct into formic acid and carbon dioxide follows both concerted and stepwise mechanisms. The latter mechanism has been overlooked previously. Under formic acid catalysis, the concerted decomposition of the cyclic carbonate may be favored under tropospheric conditions. Considering that there is a strong nexus between carbon dioxide levels in the atmosphere and global warming, the high reactivity of Criegee intermediates could be utilized for designing efficient carbon capture technologies.

  3. Global Coupled Carbon and Nitrogen Models: Successes, Failures and What next?

    NASA Astrophysics Data System (ADS)

    Holland, E. A.

    2011-12-01

    Over the last few years, there has been a great deal of progress in modeling coupled terrestrial global carbon and nitrogen cycles and their roles in Earth System models. The collection of recent models provides some surprising results and insights. A critical question for Earth system models is: How do the coupled C/N model results impact atmospheric carbon dioxide concentrations compared to carbon only models? Some coupled models predict increased atmospheric carbon dioxide concentrations, the result expected from nitrogen-limited photosynthesis uptake of carbon dioxide, while others predict little change or decreased carbon dioxide uptake with a coupled carbon and nitrogen cycle. With this range of impacts for climate critical atmospheric carbon dioxide concentrations, there is clearly a need for additional comparison of measurements and models. Randerson et al.'s CLAMP study provided important constraints and comparison for primarily for aboveground carbon uptake. However, nitrogen supply is largely determined decomposition and soil processes. I will present comparisons of NCAR's CESM results with soil and litter carbon and nitrogen fluxes and standing stocks. These belowground data sets of both carbon and nitrogen provide important benchmarks for coupled C/N models.

  4. Elevated atmospheric carbon dioxide concentrations amplify Alternaria alternata sporulation and total antigen production

    USDA-ARS?s Scientific Manuscript database

    Background: Although the association between rising levels of carbon dioxide, the principle anthropogenic greenhouse gas, and pollen production has been established, few data are available regarding the function of rising carbon dioxide on quantitative or qualitative changes in allergenic fungal sp...

  5. 46 CFR 34.15-35 - Enclosure openings-T/ALL.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY TANK VESSELS FIREFIGHTING EQUIPMENT Carbon Dioxide... of the carbon dioxide system shall automatically shut down any mechanical ventilation to that space. This will not be required where the carbon dioxide system is a secondary system in addition to another...

  6. 46 CFR 34.15-10 - Controls-T/ALL.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... GUARD, DEPARTMENT OF HOMELAND SECURITY TANK VESSELS FIREFIGHTING EQUIPMENT Carbon Dioxide Extinguishing... valves shall be used to direct the carbon dioxide into the proper space. If cylinders are used to protect... and a separate control releasing at least the required amount of carbon dioxide. These two controls...

  7. 46 CFR 95.15-35 - Enclosure openings.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... EQUIPMENT Carbon Dioxide Extinguishing Systems, Details § 95.15-35 Enclosure openings. (a) Where mechanical ventilation is provided for spaces other than cargo and similar spaces which are protected by a carbon dioxide... protected by a carbon dioxide extinguishing system, provisions shall be made for easily and effectively...

  8. 46 CFR 76.15-35 - Enclosure openings.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... Carbon Dioxide Extinguishing Systems, Details § 76.15-35 Enclosure openings. (a) Where mechanical ventilation is provided for spaces other than cargo and similar spaces which are protected by a carbon dioxide... protected by a carbon dioxide extinguishing system, provisions shall be made for easily and effectively...

  9. 46 CFR 34.15-50 - Lockout valves-T/ALL.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... COAST GUARD, DEPARTMENT OF HOMELAND SECURITY TANK VESSELS FIREFIGHTING EQUIPMENT Carbon Dioxide... carbon dioxide extinguishing system protecting a space over 6,000 cubic feet in volume and installed or... or spaces, making it impossible for carbon dioxide to discharge in the event of equipment failure...

  10. 46 CFR 34.15-35 - Enclosure openings-T/ALL.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY TANK VESSELS FIREFIGHTING EQUIPMENT Carbon Dioxide... of the carbon dioxide system shall automatically shut down any mechanical ventilation to that space. This will not be required where the carbon dioxide system is a secondary system in addition to another...

  11. 46 CFR 34.15-10 - Controls-T/ALL.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... GUARD, DEPARTMENT OF HOMELAND SECURITY TANK VESSELS FIREFIGHTING EQUIPMENT Carbon Dioxide Extinguishing... valves shall be used to direct the carbon dioxide into the proper space. If cylinders are used to protect... and a separate control releasing at least the required amount of carbon dioxide. These two controls...

  12. 46 CFR 34.15-10 - Controls-T/ALL.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... GUARD, DEPARTMENT OF HOMELAND SECURITY TANK VESSELS FIREFIGHTING EQUIPMENT Carbon Dioxide Extinguishing... valves shall be used to direct the carbon dioxide into the proper space. If cylinders are used to protect... and a separate control releasing at least the required amount of carbon dioxide. These two controls...

  13. 46 CFR 95.15-35 - Enclosure openings.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... EQUIPMENT Carbon Dioxide Extinguishing Systems, Details § 95.15-35 Enclosure openings. (a) Where mechanical ventilation is provided for spaces other than cargo and similar spaces which are protected by a carbon dioxide... protected by a carbon dioxide extinguishing system, provisions shall be made for easily and effectively...

  14. 46 CFR 34.15-50 - Lockout valves-T/ALL.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... COAST GUARD, DEPARTMENT OF HOMELAND SECURITY TANK VESSELS FIREFIGHTING EQUIPMENT Carbon Dioxide... carbon dioxide extinguishing system protecting a space over 6,000 cubic feet in volume and installed or... or spaces, making it impossible for carbon dioxide to discharge in the event of equipment failure...

  15. 46 CFR 76.15-35 - Enclosure openings.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... Carbon Dioxide Extinguishing Systems, Details § 76.15-35 Enclosure openings. (a) Where mechanical ventilation is provided for spaces other than cargo and similar spaces which are protected by a carbon dioxide... protected by a carbon dioxide extinguishing system, provisions shall be made for easily and effectively...

  16. 46 CFR 76.15-35 - Enclosure openings.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... Carbon Dioxide Extinguishing Systems, Details § 76.15-35 Enclosure openings. (a) Where mechanical ventilation is provided for spaces other than cargo and similar spaces which are protected by a carbon dioxide... protected by a carbon dioxide extinguishing system, provisions shall be made for easily and effectively...

  17. 46 CFR 34.15-10 - Controls-T/ALL.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... GUARD, DEPARTMENT OF HOMELAND SECURITY TANK VESSELS FIREFIGHTING EQUIPMENT Carbon Dioxide Extinguishing... valves shall be used to direct the carbon dioxide into the proper space. If cylinders are used to protect... and a separate control releasing at least the required amount of carbon dioxide. These two controls...

  18. 46 CFR 95.15-35 - Enclosure openings.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... EQUIPMENT Carbon Dioxide Extinguishing Systems, Details § 95.15-35 Enclosure openings. (a) Where mechanical ventilation is provided for spaces other than cargo and similar spaces which are protected by a carbon dioxide... protected by a carbon dioxide extinguishing system, provisions shall be made for easily and effectively...

  19. 46 CFR 34.15-35 - Enclosure openings-T/ALL.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY TANK VESSELS FIREFIGHTING EQUIPMENT Carbon Dioxide... of the carbon dioxide system shall automatically shut down any mechanical ventilation to that space. This will not be required where the carbon dioxide system is a secondary system in addition to another...

  20. 40 CFR 86.224-94 - Carbon dioxide analyzer calibration.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 19 2012-07-01 2012-07-01 false Carbon dioxide analyzer calibration. 86.224-94 Section 86.224-94 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... New Medium-Duty Passenger Vehicles; Cold Temperature Test Procedures § 86.224-94 Carbon dioxide...

  1. 46 CFR 34.15-50 - Lockout valves-T/ALL.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... COAST GUARD, DEPARTMENT OF HOMELAND SECURITY TANK VESSELS FIREFIGHTING EQUIPMENT Carbon Dioxide... carbon dioxide extinguishing system protecting a space over 6,000 cubic feet in volume and installed or... or spaces, making it impossible for carbon dioxide to discharge in the event of equipment failure...

  2. 46 CFR 76.15-35 - Enclosure openings.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... Carbon Dioxide Extinguishing Systems, Details § 76.15-35 Enclosure openings. (a) Where mechanical ventilation is provided for spaces other than cargo and similar spaces which are protected by a carbon dioxide... protected by a carbon dioxide extinguishing system, provisions shall be made for easily and effectively...

  3. 46 CFR 34.15-35 - Enclosure openings-T/ALL.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY TANK VESSELS FIREFIGHTING EQUIPMENT Carbon Dioxide... of the carbon dioxide system shall automatically shut down any mechanical ventilation to that space. This will not be required where the carbon dioxide system is a secondary system in addition to another...

  4. 9 CFR 313.5 - Chemical; carbon dioxide.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 9 Animals and Animal Products 2 2014-01-01 2014-01-01 false Chemical; carbon dioxide. 313.5 Section 313.5 Animals and Animal Products FOOD SAFETY AND INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE... INSPECTION AND CERTIFICATION HUMANE SLAUGHTER OF LIVESTOCK § 313.5 Chemical; carbon dioxide. The slaughtering...

  5. 9 CFR 313.5 - Chemical; carbon dioxide.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 9 Animals and Animal Products 2 2013-01-01 2013-01-01 false Chemical; carbon dioxide. 313.5 Section 313.5 Animals and Animal Products FOOD SAFETY AND INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE... INSPECTION AND CERTIFICATION HUMANE SLAUGHTER OF LIVESTOCK § 313.5 Chemical; carbon dioxide. The slaughtering...

  6. 9 CFR 313.5 - Chemical; carbon dioxide.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 9 Animals and Animal Products 2 2012-01-01 2012-01-01 false Chemical; carbon dioxide. 313.5 Section 313.5 Animals and Animal Products FOOD SAFETY AND INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE... INSPECTION AND CERTIFICATION HUMANE SLAUGHTER OF LIVESTOCK § 313.5 Chemical; carbon dioxide. The slaughtering...

  7. 46 CFR 169.565 - Fixed carbon dioxide system.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 7 2011-10-01 2011-10-01 false Fixed carbon dioxide system. 169.565 Section 169.565 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) NAUTICAL SCHOOLS SAILING SCHOOL VESSELS Lifesaving and Firefighting Equipment Firefighting Equipment § 169.565 Fixed carbon dioxide system. (a) The...

  8. 40 CFR 86.224-94 - Carbon dioxide analyzer calibration.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 18 2011-07-01 2011-07-01 false Carbon dioxide analyzer calibration... PROGRAMS (CONTINUED) CONTROL OF EMISSIONS FROM NEW AND IN-USE HIGHWAY VEHICLES AND ENGINES Emission... New Medium-Duty Passenger Vehicles; Cold Temperature Test Procedures § 86.224-94 Carbon dioxide...

  9. 46 CFR 34.15-35 - Enclosure openings-T/ALL.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY TANK VESSELS FIREFIGHTING EQUIPMENT Carbon Dioxide... of the carbon dioxide system shall automatically shut down any mechanical ventilation to that space. This will not be required where the carbon dioxide system is a secondary system in addition to another...

  10. 46 CFR 76.15-35 - Enclosure openings.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... Carbon Dioxide Extinguishing Systems, Details § 76.15-35 Enclosure openings. (a) Where mechanical ventilation is provided for spaces other than cargo and similar spaces which are protected by a carbon dioxide... protected by a carbon dioxide extinguishing system, provisions shall be made for easily and effectively...

  11. 46 CFR 108.626 - Carbon dioxide warning signs.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 4 2014-10-01 2014-10-01 false Carbon dioxide warning signs. 108.626 Section 108.626 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) A-MOBILE OFFSHORE DRILLING UNITS DESIGN AND EQUIPMENT Equipment Markings and Instructions § 108.626 Carbon dioxide warning signs. Each...

  12. 46 CFR 131.817 - Carbon dioxide warning signs.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 4 2014-10-01 2014-10-01 false Carbon dioxide warning signs. 131.817 Section 131.817 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OFFSHORE SUPPLY VESSELS OPERATIONS Markings for Fire Equipment and Emergency Equipment § 131.817 Carbon dioxide warning signs. Each entrance...

  13. 46 CFR 131.817 - Carbon dioxide warning signs.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 4 2012-10-01 2012-10-01 false Carbon dioxide warning signs. 131.817 Section 131.817 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OFFSHORE SUPPLY VESSELS OPERATIONS Markings for Fire Equipment and Emergency Equipment § 131.817 Carbon dioxide warning signs. Each entrance...

  14. 46 CFR 131.817 - Carbon dioxide warning signs.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 4 2013-10-01 2013-10-01 false Carbon dioxide warning signs. 131.817 Section 131.817 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OFFSHORE SUPPLY VESSELS OPERATIONS Markings for Fire Equipment and Emergency Equipment § 131.817 Carbon dioxide warning signs. Each entrance...

  15. 46 CFR 108.626 - Carbon dioxide warning signs.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 4 2013-10-01 2013-10-01 false Carbon dioxide warning signs. 108.626 Section 108.626 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) A-MOBILE OFFSHORE DRILLING UNITS DESIGN AND EQUIPMENT Equipment Markings and Instructions § 108.626 Carbon dioxide warning signs. Each...

  16. 46 CFR 108.626 - Carbon dioxide warning signs.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 4 2012-10-01 2012-10-01 false Carbon dioxide warning signs. 108.626 Section 108.626 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) A-MOBILE OFFSHORE DRILLING UNITS DESIGN AND EQUIPMENT Equipment Markings and Instructions § 108.626 Carbon dioxide warning signs. Each...

  17. Greenhouse Gas Fluxes at the Tablelands, NL, Canada: A Site of Active Serpentinization

    NASA Astrophysics Data System (ADS)

    Morrill, P. L.; Morrissey, L. S.; Cumming, E.

    2016-12-01

    Active sites of serpentinization have been proposed as sites for carbon capture and storage (CCS) projects. However, in addition to their ability to convert carbon dioxide to carbonate rock, sites of serpentinization also have the potential release methane, which is a more power greenhouse gas than carbon dioxide. Very little is known about the natural flux of carbon dioxide sequestered and methane released into the atmosphere from active sites of serpentinization. In this study we measured carbon dioxide, methane, and nitrous oxide gas fluxes at a pool of ultra-basic water discharging from serpentinized rock in Winterhouse Canyon, Gros Morne, Newfoundland. We found that the flux of methane released was 4.6 x 10-7 mol/m2/min and the carbon dioxide sequestered was 1.9 x 10-5 mol/m2/min, while the concentrations of nitrous oxide showed little change. Based on these fluxes we calculated predictive climate change parameters such as net radiative forcing and global warming potential which predicted that despite the methane being released the site still had an overall long-term atmospheric cooling effect based on the natural rate of carbon dioxide sequestration.

  18. Geologic framework for the national assessment of carbon dioxide storage resources─South Florida Basin: Chapter L in Geologic framework for the national assessment of carbon dioxide storage resources

    USGS Publications Warehouse

    Roberts-Ashby, Tina L.; Brennan, Sean T.; Merrill, Matthew D.; Blondes, Madalyn S.; Freeman, P.A.; Cahan, Steven M.; DeVera, Christina A.; Lohr, Celeste D.; Warwick, Peter D.; Corum, Margo D.

    2015-08-26

    This report presents five storage assessment units (SAUs) that have been identified as potentially suitable for geologic carbon dioxide sequestration within a 35,075-square-mile area that includes the entire onshore and State-water portions of the South Florida Basin. Platform-wide, thick successions of laterally extensive carbonates and evaporites deposited in highly cyclic depositional environments in the South Florida Basin provide several massive, porous carbonate reservoirs that are separated by evaporite seals. For each storage assessment unit identified within the basin, the areal distribution of the reservoir-seal couplet identified as suitable for geologic Carbon dioxide sequestration is presented, along with a description of the geologic characteristics that influence the potential carbon dioxide storage volume and reservoir performance. On a case-by-case basis, strategies for estimating the pore volume existing within structurally and (or) stratigraphically closed traps are also discussed. Geologic information presented in this report has been employed to calculate potential storage capacities for carbon dioxide sequestration in the storage assessment units assessed herein, although complete assessment results are not contained in this report.

  19. Combined goal gasifier and fuel cell system and method

    DOEpatents

    Gmeindl, Frank D.; Geisbrecht, Rodney A.

    1990-01-01

    A molten carbonate fuel cell is combined with a catalytic coal or coal char gasifier for providing the reactant gases comprising hydrogen, carbon monoxide and carbon dioxide used in the operation of the fuel cell. These reactant gases are stripped of sulfur compounds and particulate material and are then separated in discrete gas streams for conveyance to appropriate electrodes in the fuel cell. The gasifier is arranged to receive the reaction products generated at the anode of the fuel cell by the electricity-producing electrochemical reaction therein. These reaction products from the anode are formed primarily of high temperature steam and carbon dioxide to provide the steam, the atmosphere and the heat necessary to endothermically pyrolyze the coal or char in the presence of a catalyst. The reaction products generated at the cathode are substantially formed of carbon dioxide which is used to heat air being admixed with the carbon dioxide stream from the gasifier for providing the oxygen required for the reaction in the fuel cell and for driving an expansion device for energy recovery. A portion of this carbon dioxide from the cathode may be recycled into the fuel cell with the air-carbon dioxide mixture.

  20. Carbon fuel cells with carbon corrosion suppression

    DOEpatents

    Cooper, John F [Oakland, CA

    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.

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