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1

Infinite dilution partial molar volumes of platinum(II) 2,4-pentanedionate in supercritical carbon dioxide.  

PubMed

The effects of temperature and density on retention of platinum(II) 2,4-pentanedionate in supercritical fluid chromatography were investigated at temperatures of 308.15-343.15K and pressure range from 8 to 40MPa by the chromatographic impulse response method with curve fitting. The retention factors were utilized to derive the infinite dilution partial molar volumes of platinum(II) 2,4-pentanedionate in supercritical carbon dioxide. The determined partial molar volumes were small and positive at high pressures but exhibited very large and negative values in the highly compressible near critical region of carbon dioxide. PMID:25169720

Kong, Chang Yi; Siratori, Tomoya; Funazukuri, Toshitaka; Wang, Guosheng

2014-10-01

2

CARBON DIOXIDE EMISSION REDUCTION  

E-print Network

CARBON DIOXIDE EMISSION REDUCTION TECHNOLOGIES AND MEASURES IN US INDUSTRIAL SECTOR FINAL REPORT TO KOREA ENVIRONMENT INSTITUTE FEBRUARY 2007 #12;B #12;C CARBON DIOXIDE EMISSION REDUCTION TECHNOLOGIES.5 Primary Energy Use and Carbon Dioxide Emissions for Selected US Chemical Subsectors in 1994

Delaware, University of

3

Carbon Dioxide & Global Warming  

E-print Network

Carbon Dioxide & Global Warming University of MiaMi rosenstiel sChool of Marine anD atMospheriC s ­ it allows sunlight in, but gases in the atmosphere, especially carbon dioxide (CO2 ), allow less to breathe. Respi- ration by these organisms returns this carbon to the atmosphere as CO2 . Unfortunately

Miami, University of

4

The carbon dioxide cycle  

USGS Publications Warehouse

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.

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

2005-01-01

5

Temperature VS Carbon Dioxide  

NSDL National Science Digital Library

In this activity, students examine the relationship between carbon dioxide levels and global temperature change by studying a graph of these two variables. They will discover that by using data from ice cores, scientists can determine temperature and carbon dioxide levels in the air as far back as a hundred thousand years in the past. The students try to predict which variable is the independent one and then make a graph of temperature change and carbon dioxide levels. After making their graph, students describe the relationship between temperature and carbon dioxide levels in the atmosphere to determine if their predictions were correct.

6

Production of Carbon Dioxide  

NSDL National Science Digital Library

In this chemistry activity, learners use common chemicals to produce carbon dioxide and observe its properties. This resource includes brief questions for learners to answer after the experiment. Use this activity to introduce learners to carbon dioxide and its use as a fire extinguisher. Note: this activity involves an open flame.

House, The S.

2014-01-28

7

Carbon Dioxide Emission Estimates  

NSDL National Science Digital Library

The Carbon Dioxide Information Analysis Center of the Oak Ridge National Laboratory provides this new data on carbon dioxide emissions from fossil fuel burning, hydraulic cement production, and gas flaring in 1995. Data for one degree grid cells can be downloaded from the site in addition to code for analysis of the data.

8

Carbon Dioxide and Climate.  

ERIC Educational Resources Information Center

The amount of carbon dioxide in the atmosphere is increasing at a rate that could cause significant warming of the Earth's climate in the not too distant future. Oceanographers are studying the role of the ocean as a source of carbon dioxide and as a sink for the gas. (Author/BB)

Brewer, Peter G.

1978-01-01

9

Shock-tube thermochemistry tables for high-temperature gases. Volume 5: Carbon dioxide  

NASA Technical Reports Server (NTRS)

Equilibrium thermodynamic properties and species concentrations for carbon dioxide are tabulated for moving, standing, and reflected shock waves. Initial pressures range from 6.665 to 6665 N/sq m (0.05 to 50.0 torr), and temperatures from 2,000 to over 80,000K. In this study, 20 molecular and atomic species were considered.

Menard, W. A.; Horton, T. E.

1971-01-01

10

NATIONAL PERFORMANCE AUDIT PROGRAM: 1979 PROFICIENCY SURVEYS FOR SULFUR DIOXIDE, NITROGEN DIOXIDE, CARBON MONOXIDE, SULFATE, NITRATE, LEAD AND HIGH VOLUME FLOW  

EPA Science Inventory

The Quality Assurance Division of the Environmental Monitoring Systems Laboratory, Research Triangle Park, North Carolina, administers semiannual Surveys of Analytical Proficiency for sulfur dioxide, nitrogen dioxide, carbon monoxide, sulfate, nitrate and lead. Sample material, s...

11

Carbon Dioxide for pH Control  

SciTech Connect

Cardox, the major supplier of carbon dioxide, has developed a diffuser to introduce carbon dioxide into a water volume as small bubbles to minimize reagent loss to the atmosphere. This unit is integral to several configurations suggested for treatment to control alkalinity in water streams.

Wagonner, R.C.

2001-08-16

12

Carbon dioxide sensor  

DOEpatents

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).

Dutta, Prabir K. (Worthington, OH); Lee, Inhee (Columbus, OH); Akbar, Sheikh A. (Hilliard, OH)

2011-11-15

13

Carbon Dioxide Removal  

NSDL National Science Digital Library

In this experiment using sprigs of Elodea, learners will observe a natural process that removes carbon dioxide (CO2) from Earth's atmosphere. This process is a part of the carbon cycle and results in temperature suitable for life. Note: this experiment requires that learners make observations an hour or the next day after they set up the materials.

2012-12-26

14

Carbon Dioxide - Our Common "Enemy"  

NASA Technical Reports Server (NTRS)

Health effects of brief and prolonged exposure to carbon dioxide continue to be a concern for those of us who manage this pollutant in closed volumes, such as in spacecraft and submarines. In both examples, considerable resources are required to scrub the atmosphere to levels that are considered totally safe for maintenance of crew health and performance. Defining safe levels is not a simple task because of many confounding factors, including: lack of a robust database on human exposures, suspected significant variations in individual susceptibility, variations in the endpoints used to assess potentially adverse effects, the added effects of stress, and the fluid shifts associated with micro-gravity (astronauts only). In 2007 the National Research Council proposed revised Continuous Exposure Guidelines (CEGLs) and Emergency Exposure Guidelines (EEGLs) to the U.S. Navy. Similarly, in 2008 the NASA Toxicology Group, in cooperation with another subcommittee of the National Research Council, revised Spacecraft Maximum Allowable Concentrations (SMACs). In addition, a 1000-day exposure limit was set for long-duration spaceflights to celestial bodies. Herein we examine the rationale for the levels proposed to the U.S. Navy and compare this rationale with the one used by NASA to set its limits. We include a critical review of previous studies on the effects of exposure to carbon dioxide and attempt to dissect out the challenges associated with setting fully-defensible limits. We also describe recent experiences with management of carbon dioxide aboard the International Space Station with 13 persons aboard. This includes the tandem operations of the Russian Vozduk and the U.S. Carbon Dioxide Removal System. A third removal system is present while the station is docked to the Shuttle spacecraft, so our experience includes the lithium hydroxide system aboard Shuttle for the removal of carbon dioxide. We discuss strategies for highly-efficient, regenerable removal of carbon dioxide that could meet the 1000-day SMAC of 0.5%, which would apply to long-duration voyages to Mars.

James, John T.; Macatangay, Ariel

2009-01-01

15

Carbon Dioxide Exercise  

NSDL National Science Digital Library

In this activity, students work in groups, plotting carbon dioxide concentrations over time on overheads and estimating the rate of change over five years. Stacked together, the overheads for the whole class show an increase on carbon dioxide over five years and annual variation driven by photosynthesis. This exercise enables students to practice basic quantitative skills and understand how important sampling intervals can be when studying changes over time. A goal is to see how small sample size may give incomplete picture of data.

Richardson, Randy; Collection, Serc -.

16

Carbon Dioxide Laser Guidelines  

PubMed Central

The carbon dioxide (CO2) laser is a versatile tool that has applications in ablative lasing and caters to the needs of routine dermatological practice as well as the aesthetic, cosmetic and rejuvenation segments. This article details the basics of the laser physics as applicable to the CO2 laser and offers guidelines for use in many of the above indications. PMID:20808594

Krupa Shankar, DS; Chakravarthi, M; Shilpakar, Rachana

2009-01-01

17

Bench Remarks: Carbon Dioxide.  

ERIC Educational Resources Information Center

Discusses the properties of carbon dioxide in its solid "dry ice" stage. Suggests several demonstrations and experiments that use dry ice to illustrate Avogadro's Law, Boyle's Law, Kinetic-Molecular Theory, and the effects of dry ice in basic solution, in limewater, and in acetone. (TW)

Bent, Henry A.

1987-01-01

18

Carbon Dioxide Increases  

NSDL National Science Digital Library

In this problem set, learners will analyze the Keeling Curve showing carbon dioxide concentration in the atmosphere since 1985 to answer a series of questions. Answer key is provided. This is part of Earth Math: A Brief Mathematical Guide to Earth Science and Climate Change.

19

Atmospheric Carbon Dioxide  

NSDL National Science Digital Library

This figure, the famous Keeling Curve, shows the history of atmospheric carbon dioxide concentrations as directly measured at Mauna Loa, Hawaii. This curve is an essential piece of evidence that shows the increased greenhouse gases that cause recent increases in global temperatures.

Robert A. Rohde

20

Carbon dioxide dangers demonstration model  

USGS Publications Warehouse

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.

Venezky, Dina; Wessells, Stephen

2010-01-01

21

Electrochemically regenerable carbon dioxide absorber  

NASA Technical Reports Server (NTRS)

Preliminary designs were generated for two electrochemically regenerable carbon dioxide absorber concepts. Initially, an electrochemically regenerable absorption bed concept was designed. This concept incorporated the required electrochemical regeneration components in the absorber design, permitting the absorbent to be regenerated within the absorption bed. This hardware was identified as the electrochemical absorber hardware. The second hardware concept separated the functional components of the regeneration and absorption process. This design approach minimized the extravehicular activity component volume by eliminating regeneration hardware components within the absorber. The electrochemical absorber hardware was extensively characterized for major operating parameters such as inlet carbon dioxide partial pressure, process air flow rate, operational pressure, inlet relative humidity, regeneration current density and absorption/regeneration cycle endurance testing.

Woods, R. R.; Marshall, R. D.; Schubert, F. H.; Heppner, D. B.

1979-01-01

22

CARBON DIOXIDE FIXATION.  

SciTech Connect

Solar carbon dioxide fixation offers the possibility of a renewable source of chemicals and fuels in the future. Its realization rests on future advances in the efficiency of solar energy collection and development of suitable catalysts for CO{sub 2} conversion. Recent achievements in the efficiency of solar energy conversion and in catalysis suggest that this approach holds a great deal of promise for contributing to future needs for fuels and chemicals.

FUJITA,E.

2000-01-12

23

Modeling Carbon Dioxide Levels  

NSDL National Science Digital Library

In this activity students will explore levels of Carbon Dioxide ( C02) in the atmosphere over time. There is concern that levels of C02 are rising; and finding a good mathematical model for CO2 levels is an important part of determining if this is attributable to human technology. Students draw a scatter plot, choose two points to create a linear model for the data, then use the model to make predictions.

2009-01-01

24

Carbon dioxide sequestration by mineral carbonation  

Microsoft Academic Search

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

W. J. J. Huijgen; R. N. J. Comans

2007-01-01

25

Carbon Dioxide Reduction Through Urban Forestry  

E-print Network

Carbon Dioxide Reduction Through Urban Forestry: Guidelines for Professional and Volunteer Tree; Simpson, James R. 1999. Carbon dioxide reduction through urban forestry of Agriculture; 237 p. Carbon dioxide reduction through urban forestry--Guidelines for professional and volunteer

Standiford, Richard B.

26

Carbon dioxide and climate  

SciTech Connect

Scientific and public interest in greenhouse gases, climate warming, and global change virtually exploded in 1988. The Department's focused research on atmospheric CO{sub 2} contributed sound and timely scientific information to the many questions produced by the groundswell of interest and concern. Research projects summarized in this document provided the data base that made timely responses possible, and the contributions from participating scientists are genuinely appreciated. In the past year, the core CO{sub 2} research has continued to improve the scientific knowledge needed to project future atmospheric CO{sub 2} concentrations, to estimate climate sensitivity, and to assess the responses of vegetation to rising concentrations of CO{sub 2} and to climate change. The Carbon Dioxide Research Program's goal is to develop sound scientific information for policy formulation and governmental action in response to changes of atmospheric CO{sub 2}. The Program Summary describes projects funded by the Carbon Dioxide Research Program during FY 1990 and gives a brief overview of objectives, organization, and accomplishments.

Not Available

1990-10-01

27

Coral reefs and carbon dioxide  

SciTech Connect

This commentary argues the conclusion from a previous article, which investigates diurnal changes in carbon dioxide partial pressure and community metabolism on coral reefs, that coral `reefs might serve as a sink, not a source, for atmospheric carbon dioxide.` Commentaries from two groups are given along with the response by the original authors, Kayanne et al. 27 refs.

Buddemeier, R.W. [Kansas Geological Survey, Lawrence, KS (United States)

1996-03-01

28

Method for Extracting and Sequestering Carbon Dioxide  

SciTech Connect

A method and apparatus to extract and sequester carbon dioxide (CO2) from a stream or volume of gas wherein said method and apparatus hydrates CO2, and reacts the resulting carbonic acid with carbonate. Suitable carbonates include, but are not limited to, carbonates of alkali metals and alkaline earth metals, preferably carbonates of calcium and magnesium. Waste products are metal cations and bicarbonate in solution or dehydrated metal salts, which when disposed of in a large body of water provide an effective way of sequestering CO2 from a gaseous environment.

Rau, Gregory H.; Caldeira, Kenneth G.

2005-05-10

29

Apparatus for extracting and sequestering carbon dioxide  

DOEpatents

An apparatus and method associated therewith to extract and sequester carbon dioxide (CO.sub.2) from a stream or volume of gas wherein said apparatus hydrates CO.sub.2 and reacts the resulting carbonic acid with carbonate. Suitable carbonates include, but are not limited to, carbonates of alkali metals and alkaline earth metals, preferably carbonates of calcium and magnesium. Waste products are metal cations and bicarbonate in solution or dehydrated metal salts, which when disposed of in a large body of water provide an effective way of sequestering CO.sub.2 from a gaseous environment.

Rau, Gregory H. (Castro Valley, CA); Caldeira, Kenneth G. (Livermore, CA)

2010-02-02

30

Method for extracting and sequestering carbon dioxide  

DOEpatents

A method and apparatus to extract and sequester carbon dioxide (CO.sub.2) from a stream or volume of gas wherein said method and apparatus hydrates CO.sub.2, and reacts the resulting carbonic acid with carbonate. Suitable carbonates include, but are not limited to, carbonates of alkali metals and alkaline earth metals, preferably carbonates of calcium and magnesium. Waste products are metal cations and bicarbonate in solution or dehydrated metal salts, which when disposed of in a large body of water provide an effective way of sequestering CO.sub.2 from a gaseous environment.

Rau, Gregory H. (Castro Valley, CA); Caldeira, Kenneth G. (Livermore, CA)

2005-05-10

31

Sampling Carbon Dioxide  

NSDL National Science Digital Library

In this lab activity, student teams hypothesize which source has a greater becomes CO² concentration: their breath, auto exhaust, or air in the classroom. They test gas samples from each of these sources, plot data, and hypothesize about the respective role engine exhaust and animal respiration play in contemporary climate change. The lab procedures require Bromthymol Blue indicator solution (BTB), household ammonia, vinegar, and balloons. Links to videos supporting the investigations are provided. This activity is supported by a textbook chapter, "How is Carbon Dioxide Measured?," part of the unit, Climate Change, in Global Systems Science (GSS), an interdisciplinary course for high school students that emphasizes how scientists from a wide variety of fields work together to understand significant problems of global impact.

32

Geologic Sequestration of Carbon Dioxide  

NASA Astrophysics Data System (ADS)

Geologic sequestration of carbon dioxide has emerged as one of the most promising options for making deep cuts in carbon dioxide emissions. Geologic sequestration involves the two-step process of first capturing carbon dioxide by separating it from stack emissions, followed by injection and long term storage in deep geologic formations. Sedimentary basins, including depleted oil and gas reservoirs, deep unminable coal seams, and brine-filled formations, provide the most attractive storage reservoirs. Over the past few years significant advances have been made in this technology, including development of simulation models and monitoring systems, implementation of commercial scale demonstration projects, and investigation of natural and industrial analogues for geologic storage of carbon dioxide. While much has been accomplished in a short time, there are many questions that must be answered before this technology can be employed on the scale needed to make significant reductions in carbon dioxide emissions. Questions such as how long must the carbon dioxide remain underground, to what extent will geochemical reactions completely immobilize the carbon dioxide, what can be done in the event that a storage site begins to leak at an unacceptable rate, what is the appropriate risk assessment, regulatory and legal framework, and will the public view this option favorably? This paper will present recent advances in the scientific and technological underpinnings of geologic sequestration and identify areas where additional information is needed.

Benson, S. M.

2003-04-01

33

Reducing carbon dioxide to products  

DOEpatents

A method reducing carbon dioxide to one or more products may include steps (A) to (C). Step (A) may bubble said carbon dioxide into a solution of an electrolyte and a catalyst in a divided electrochemical cell. The divided electrochemical cell may include an anode in a first cell compartment and a cathode in a second cell compartment. The cathode may reduce said carbon dioxide into said products. Step (B) may adjust one or more of (a) a cathode material, (b) a surface morphology of said cathode, (c) said electrolyte, (d) a manner in which said carbon dioxide is bubbled, (e), a pH level of said solution, and (f) an electrical potential of said divided electrochemical cell, to vary at least one of (i) which of said products is produced and (ii) a faradaic yield of said products. Step (C) may separate said products from said solution.

Cole, Emily Barton; Sivasankar, Narayanappa; Parajuli, Rishi; Keets, Kate A

2014-09-30

34

NASA Satellite Sees Carbon Dioxide  

NSDL National Science Digital Library

In this problem set, learners will analyze a map of atmospheric carbon dioxide derived from satellite data. Answer key is provided. This is part of Earth Math: A Brief Mathematical Guide to Earth Science and Climate Change.

35

Carbon Dioxide and Ocean Acidification  

NSDL National Science Digital Library

Demonstrates the affect of increased dissolved carbon dioxide on water pH using a cheap, non-toxic acid/base indicator. Students bubble breath through a straw into red cabbage juice and note the color change.

Chris Lewis

36

Recuperative supercritical carbon dioxide cycle  

DOEpatents

A power plant includes a closed loop, supercritical carbon dioxide system (CLS-CO.sub.2 system). The CLS-CO.sub.2 system includes a turbine-generator and a high temperature recuperator (HTR) that is arranged to receive expanded carbon dioxide from the turbine-generator. The HTR includes a plurality of heat exchangers that define respective heat exchange areas. At least two of the heat exchangers have different heat exchange areas.

Sonwane, Chandrashekhar; Sprouse, Kenneth M; Subbaraman, Ganesan; O'Connor, George M; Johnson, Gregory A

2014-11-18

37

Molecular Structure of Carbon Dioxide  

NSDL National Science Digital Library

Carbon dioxide was first described in the 17th century by Jan Baptist van Helmont, a Belgium chemist. The chemical CO2 is released into the atmosphere when carbon-containing fossil fuels like oil, natural gas, and coal are burned in air. It is also produced by various microorganisms in fermentation and is breathed out by animals. Plants absorb carbon dioxide during photosynthesis, using both the carbon and the oxygen to construct carbohydrates. Every year the amount of CO2 in the atmosphere is increasing. CO2 build-up in the atmosphere is caused by deforestation, therefore reducing the number of trees available to absorb CO2. Excess CO2 in the environment causes Global Warming and the Greenhouse Effect. It is also toxic to humans since inhalation of large amounts of CO2 can cause suffocation. Some beverages, such as beer and sparkling wine contain carbon dioxide as a result of fermentation.

2002-08-15

38

Magnesite disposal of carbon dioxide  

SciTech Connect

In this paper we report our progress on developing a method for carbon dioxide disposal whose purpose it is to maintain coal energy competitive even is environmental and political pressures will require a drastic reduction in carbon dioxide emissions. In contrast to most other methods, our approach is not aiming at a partial solution of the problem, or at buying time for phasing out fossil energy. Instead, its purpose is to obtain a complete and economic solution of the problem, and thus maintain access to the vast fossil energy reservoir. A successful development of this technology would guarantee energy availability for many centuries even if world economic growth the most optimistic estimates that have been put forward. Our approach differs from all others in that we are developing an industrial process which chemically binds the carbon dioxide in an exothermic reaction into a mineral carbonate that is thermodynamically stable and environmentally benign.

Lackner, K.S.; Butt, D.P.; Wendt, C.H.

1997-08-01

39

Carbon dioxide enhances fragility of ice crystals  

NASA Astrophysics Data System (ADS)

Ice caps and glaciers cover 7% of the Earth, greater than the land area of Europe and North America combined, and play an important role in global climate. The small-scale failure mechanisms of ice fracture, however, remain largely elusive. In particular, little understanding exists about how the presence and concentration of carbon dioxide molecules, a significant component in the atmosphere, affects the propensity of ice to fracture. Here we use atomic simulations with the first-principles based ReaxFF force field capable of describing the details of chemical reactions at the tip of a crack, applied to investigate the effects of the presence of carbon dioxide molecules on ice fracture. Our result shows that increasing concentrations of carbon dioxide molecules significantly decrease the fracture toughness of the ice crystal, making it more fragile. Using enhanced molecular sampling with metadynamics we reconstruct the free energy landscape in varied chemical microenvironments and find that carbon dioxide molecules affect the bonds between water molecules at the crack tip and decrease their strength by altering the dissociation energy of hydrogen bonds. In the context of glacier dynamics our findings may provide a novel viewpoint that could aid in understanding the breakdown and melting of glaciers, suggesting that the chemical composition of the atmosphere can be critical to mediate the large-scale motion of large volumes of ice.

Qin, Zhao; Buehler, Markus J.

2012-11-01

40

Process for sequestering carbon dioxide and sulfur dioxide  

DOEpatents

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.

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

41

Carbon dioxide transport over complex terrain  

USGS Publications Warehouse

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.

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

2004-01-01

42

Carbon Dioxide - Sources and Sinks  

NSDL National Science Digital Library

In this lab activity, students use a chemical indicator (bromothymol blue) to detect the presence of carbon dioxide in animal and plant respiration and in the burning of fossil fuels and its absence in the products of plant photosynthesis. After completing the five parts of this activity, students compare the colors of the chemical indicator in each part and interpret the results in terms of the qualitative importance of carbon sinks and sources.

Universe, Windows T.

43

Photolytical Generation of Carbon Dioxide  

Microsoft Academic Search

Carbon dioxide has been found by Cassini VIMS throughout the Saturnian system in locations such as Iapetus' equator where the temperature is too high for it to remain as free ice for more than a few hundred years. We suggest that the 4.26 micron absorption feature found on Iapetus and Hyperion (that has been attributed to complexed CO2) is the

E. E. Palmer; R. H. Brown

2008-01-01

44

Thermal Infrared Radiation and Carbon Dioxide in the Atmosphere  

E-print Network

Thermal Infrared Radiation and Carbon Dioxide in the Atmosphere Bill Satzer 3M Company #12;Outline · Radiation spectra ­ incoming and outgoing · Physical setting ­ characteristics of the atmosphere · CO2 dioxide Water vapor #12;Atmospheric composition (parts per million by volume) · Nitrogen (N2) 780

Olver, Peter

45

Carbon Dioxide Removal via Passive Thermal Approaches  

NASA Technical Reports Server (NTRS)

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.

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

2011-01-01

46

VAPOR + LIQUID EQUILIBRIUM OF WATER, CARBON DIOXIDE, AND THE BINARY SYSTEM WATER + CARBON DIOXIDE FROM  

E-print Network

) were used to describe the properties of the pure substances. The vapor pressures of water and carbonVAPOR + LIQUID EQUILIBRIUM OF WATER, CARBON DIOXIDE, AND THE BINARY SYSTEM WATER + CARBON DIOXIDE the vapor-liquid equilibrium of water (between 323 and 573 K), carbon dioxide (between 230 and 290 K

47

Carbon dioxide review 1982  

SciTech Connect

The buildup of CO/sub 2/ is a reality, monitored with increasing precision since 1957 and inferred for much earlier dates. A statistical section gives the monitored values to 1980, as well as a review of a long series of measurements made at Mauna Loa by the pioneers of such monitoring, Charles D. Keeling, Robert B. Bacastow, and Timothy P. Whorf. The book discusses internal transport processes in the ocean, of ocean-atmosphere interaction, of the magnitude of forest and soil carbon wastage, of the future course of fossil-fuel consumption. Yet something else emerges, too: if the CO/sub 2/ buildup continues; if the big general circulation models are right about its impact on climate, and if we have not miscalculated the potential role of the oceans, then we face a climatic change in the next century and a half like nothing the post-glacial world, and hence civilized humanity, has seen.

Clark, W.C. (ed.)

1982-01-01

48

Determination of the Effective Volume of an Automated Chamber System for Studying the Effect of Soil Wetting and Drying Cycles on Carbon Dioxide and Methane Soil Fluxes  

NASA Astrophysics Data System (ADS)

Measurement of terrestrial greenhouse gas (GHG) fluxes is essential for estimating and managing the effects of the human carbon footprint. This poster presentation describes a method of determining the effective volume of an automated non-steady state chamber system in order to simultaneously measure carbon dioxide (CO2) and methane (CH4) fluxes at the soil surface. Our method used a Picarro G2301-f Cavity Ring-Down Spectrometer coupled to our automated chamber system (developed by the UBC Biometeorology and Soil Physics Group) to allow for continuous, half-hourly measurements of CO2 and CH4 fluxes. The high precision of the spectrometer allowed for a relatively short 4-minute closure time of the chamber, which was sufficient for flux calculations of both CO2 and CH4. Following the closure of the 65-L chamber, ambient air was drawn into the chamber and then through the spectrometer at a flow rate of approximately 0.25 L min-1. A calibration gas (20% by volume CO2 or 0.10% by volume CH4) was injected into the chamber at a flow rate of 15 mL min-1. The chamber was fixed to an aluminum base during calibration injections, which were performed separately for CO2 and CH4. Rates of increase in chamber headspace GHG concentrations were found to be linear. The effective volume of the chamber, an essential parameter in flux calculation, was found to exceed the geometric volume of the chamber by about 8% for CO2 and 1% for CH4. Results indicated that our non-steady state system can be used to accurately measure CO2 and CH4 fluxes simultaneously and provides a novel way to approach both field and laboratory-based GHG flux assessment. Additionally, the use of the system to determine the effects of soil wetting events on CO2 and CH4 emissions will be described.

Webster, C.; Johnson, M. S.; Jassal, R. S.; Black, T. A.; Hawthorne, I.

2013-12-01

49

Capture of carbon dioxide by hybrid sorption  

DOEpatents

A composition, process and system for capturing carbon dioxide from a combustion gas stream. The composition has a particulate porous support medium that has a high volume of pores, an alkaline component distributed within the pores and on the surface of the support medium, and water adsorbed on the alkaline component, wherein the proportion of water in the composition is between about 5% and about 35% by weight of the composition. The process and system contemplates contacting the sorbent and the flowing gas stream together at a temperature and for a time such that some water remains adsorbed in the alkaline component when the contact of the sorbent with the flowing gas ceases.

Srinivasachar, Srivats

2014-09-23

50

The Change in Carbon Dioxide Levels  

NSDL National Science Digital Library

In this lesson students discover that ice cores can help us learn not only the temperature of the Earth in times past, but also the amount of Carbon Dioxide trapped in the air bubbles in the ice. This activity uses as source data a plot of each versus time, and asks the students to plot the Temperature variable versus the other variable which is the Carbon Dioxide content. Students can fit the data to a line y = mx + b to see how changes in Temperature and related to changes in Carbon Dioxide. After they make a graph of Carbon Dioxide concentration as a function of time, they will learn about linear trends in the data, as well as the annual variation of Carbon Dioxide and will then predict the level of Carbon Dioxide in a future year from the data.

51

Solubility of Carbon Dioxide in Water.  

ERIC Educational Resources Information Center

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)

Bush, Pat; And Others

1992-01-01

52

Carbon Dioxide Capture from Coal-Fired  

E-print Network

Carbon Dioxide Capture from Coal-Fired Power Plants: A Real Options Analysis May 2005 MIT LFEE 2005 are valued using the "real options" valuation methodology in an uncertain carbon dioxide (CO2) price support for the work was provided by the Carbon Sequestration Initiative. The authors acknowledge Linda Ye

53

Carbon Cycle: Exchanging Carbon Dioxide between the Atmosphere and Ocean  

NSDL National Science Digital Library

This lab investigates the exchange of carbon dioxide between the atmosphere and the ocean's surface. It is based on the fact that carbon dioxide dissolves in the ocean and provides the source of that plants and plankton living in the ocean rely on for photosynthesis. Students will discover that the amount of carbon dioxide the ocean can contain depends on the temperature of the water and its salinity (whether it is sea water or fresh water) and that cold water can hold more carbon dioxide in solution than warm water. They will observe that when carbon dioxide dissolves in water, it forms carbonic acid which makes the water acidic, and they will test for the acidity caused by the presence of dissolved carbon dioxide using Universal Indicator, which turns yellow when the solution is acidic. This activity tests whether sea water or fresh water absorbs more carbon dioxide.

54

46 CFR 131.817 - Carbon dioxide warning signs.  

Code of Federal Regulations, 2014 CFR

...2014-10-01 2014-10-01 false Carbon dioxide warning signs. 131.817 ...and Emergency Equipment 131.817 Carbon dioxide warning signs. Each entrance to a space storing carbon dioxide cylinders, a space...

2014-10-01

55

46 CFR 193.15-20 - Carbon dioxide storage.  

Code of Federal Regulations, 2014 CFR

...2014-10-01 2014-10-01 false Carbon dioxide storage. 193.15-20...VESSELS FIRE PROTECTION EQUIPMENT Carbon Dioxide and Clean Agent Extinguishing Systems, Details 193.15-20 Carbon dioxide storage. (a)...

2014-10-01

56

46 CFR 108.431 - Carbon dioxide systems: General.  

Code of Federal Regulations, 2014 CFR

...2014-10-01 2014-10-01 false Carbon dioxide systems: General. 108.431...EQUIPMENT Fire Extinguishing Systems Fixed Carbon Dioxide Fire Extinguishing Systems 108.431 Carbon dioxide systems: General. (a)...

2014-10-01

57

46 CFR 169.565 - Fixed carbon dioxide system.  

Code of Federal Regulations, 2014 CFR

...2014-10-01 2014-10-01 false Fixed carbon dioxide system. 169.565 Section 169...Firefighting Equipment 169.565 Fixed carbon dioxide system. (a) The number of pounds of carbon dioxide required for each space...

2014-10-01

58

46 CFR 196.37-8 - Carbon dioxide warning signs.  

Code of Federal Regulations, 2014 CFR

...2014-10-01 2014-10-01 false Carbon dioxide warning signs. 196.37-8...Emergency Equipment, etc. 196.37-8 Carbon dioxide warning signs. Each entrance to a space storing carbon dioxide cylinders, a space...

2014-10-01

59

46 CFR 108.626 - Carbon dioxide warning signs.  

Code of Federal Regulations, 2014 CFR

...2014-10-01 2014-10-01 false Carbon dioxide warning signs. 108.626 ...Markings and Instructions 108.626 Carbon dioxide warning signs. Each entrance to a space storing carbon dioxide cylinders, a space...

2014-10-01

60

46 CFR 78.47-11 - Carbon dioxide warning signs.  

Code of Federal Regulations, 2014 CFR

...2014-10-01 2014-10-01 false Carbon dioxide warning signs. 78.47-11...Emergency Equipment, Etc. 78.47-11 Carbon dioxide warning signs. Each entrance to a space storing carbon dioxide cylinders, a space...

2014-10-01

61

46 CFR 97.37-11 - Carbon dioxide warning signs.  

Code of Federal Regulations, 2014 CFR

...2014-10-01 2014-10-01 false Carbon dioxide warning signs. 97.37-11...Emergency Equipment, Etc. 97.37-11 Carbon dioxide warning signs. Each entrance to a space storing carbon dioxide cylinders, a space...

2014-10-01

62

49 CFR 179.102-1 - Carbon dioxide, refrigerated liquid.  

Code of Federal Regulations, 2014 CFR

...2014-10-01 2014-10-01 false Carbon dioxide, refrigerated liquid. 179...114 and 120) 179.102-1 Carbon dioxide, refrigerated liquid. (a) Tank cars used to transport carbon dioxide, refrigerated liquid...

2014-10-01

63

Silanediol-catalyzed carbon dioxide fixation.  

PubMed

Carbon dioxide is an abundant and renewable C1 source. However, mild transformations with carbon dioxide at atmospheric pressure are difficult to accomplish. Silanediols have been discovered to operate as effective hydrogen-bond donor organocatalysts for the atom-efficient conversion of epoxides to cyclic carbonates under environmentally friendly conditions. The reaction system is tolerant of a variety of epoxides and the desired cyclic carbonates are isolated in excellent yields. PMID:25328125

Hardman-Baldwin, Andrea M; Mattson, Anita E

2014-12-01

64

Interglacials, Milankovitch Cycles, and Carbon Dioxide  

E-print Network

The existing understanding of interglacial periods is that they are initiated by Milankovitch cycles enhanced by rising atmospheric carbon dioxide concentrations. During interglacials, global temperature is also believed to be primarily controlled by carbon dioxide concentrations, modulated by internal processes such as the Pacific Decadal Oscillation and the North Atlantic Oscillation. Recent work challenges the fundamental basis of these conceptions.

Gerald E. Marsh

2010-02-11

65

CARBON DIOXIDE STORAGE IN PENNSYLVANIA PASTURES  

Technology Transfer Automated Retrieval System (TEKTRAN)

Global warming, caused primarily by the burning of fossil fuels and the resulting increase in atmospheric greenhouse gasses such as carbon dioxide, is increasingly being recognized as a concern for the wellbeing of the planet. Agricultural practices that increase carbon dioxide storage in soil organ...

66

Encapsulated liquid sorbents for carbon dioxide capture.  

PubMed

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. PMID:25652243

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

2015-01-01

67

Carbon dioxide sequestration by mineral carbonation  

SciTech Connect

Concerns about global warming caused by the increasing concentration of carbon dioxide and other greenhouse gases in the earths atmosphere have resulted in the need for research to reduce or eliminate emissions of these gases. Carbonation of magnesium and calcium silicate minerals is one possible method to achieve this reduction. It is possible to carry out these reactions either in situ (storage underground and subsequent reaction with the host rock to trap CO2 as carbonate minerals) or ex situ (above ground in a more traditional chemical processing plant). Research at the Department of Energys Albany Research Center has explored both of these routes. This paper will explore parameters that affect the direct carbonation of magnesium silicate minerals serpentine (Mg3Si2O5(OH)4) and olivine (Mg2SiO4) to produce magnesite (MgCO3), as well as the calcium silicate mineral, wollastonite (CaSiO3), to form calcite (CaCO3). The Columbia River Basalt Group is a multi-layered basaltic lava plateau that has favorable mineralogy and structure for storage of CO2. Up to 25% combined concentration of Ca, Fe2+, and Mg cations could react to form carbonates and thus sequester large quantities of CO2. Core samples from the Columbia River Basalt Group were reacted in an autoclave for up to 2000 hours at temperatures and pressures to simulate in situ conditions. Changes in core porosity, secondary minerals, and solution chemistry were measured.

Gerdemann, Stephen J.; Dahlin David C.; O'Connor William K.; Penner Larry R.

2003-11-01

68

Energy Prices, Taxes and Carbon Dioxide Emissions  

Microsoft Academic Search

Taxes levied on the carbon content of fuels (carbon taxes) are being considered in many OECD countries as a possible policy instrument to reduce carbon dioxide emissions. This paper first reviews the policy response in Member countries to the threat of global warming. It then discusses the link between carbon emission intensities and current energy prices, touching also on the

Peter Hoeller; Markku Wallin

1991-01-01

69

Carbon dioxide capture process with regenerable sorbents  

DOEpatents

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.

Pennline, Henry W. (Bethel Park, PA); Hoffman, James S. (Library, PA)

2002-05-14

70

Aversive reactions of turkeys to argon, carbon dioxide and a mixture of carbon dioxide and argon.  

PubMed

The reactions of turkeys to the presence of either 90 per cent argon in air (anoxia), 72 per cent carbon dioxide in air or a mixture of 30 per cent carbon dioxide and 60 per cent argon in air with 3 per cent residual oxygen were tested. The majority of the turkeys did not avoid a feeding chamber containing either argon or the mixture of carbon dioxide and argon, but 50 per cent of the turkeys avoided a feeding chamber containing 72 per cent carbon dioxide in air. It is concluded that from the point of view of welfare, either 90 per cent argon in air or a mixture of 30 per cent carbon dioxide and 60 per cent argon in air, would be preferable to a high concentration of carbon dioxide for stunning/killing turkeys. PMID:8799986

Raj, A B

1996-06-15

71

Photolytical Generation of Carbon Dioxide  

NASA Astrophysics Data System (ADS)

Carbon dioxide has been found by Cassini VIMS throughout the Saturnian system in locations such as Iapetus' equator where the temperature is too high for it to remain as free ice for more than a few hundred years. We suggest that the 4.26 micron absorption feature found on Iapetus and Hyperion (that has been attributed to complexed CO2) is the result of either UV photolysis or ion bombardment driving chemistry between the carbon rich layer and the water ice regolith. We conducted experiments to simulate the generation of CO2 by UV radiation under conditions similar to those on the surface of Iapetus. A simulated icy regolith was created in an argon atmosphere using flash-frozen, degassed water crushed into sub-millimeter sized particles. Isotopically labeled amorphous carbon (13C), which was ground into a fine dust, was mixed into the regolith allowing for extensive grain contact. This sample was placed in a vacuum chamber and cooled to temperatures as low at 60K. The sample was irradiated with UV light, and the products were measured using both a mass spectrometer to identify free molecules and an IR spectrometer for molecules that remained trapped on and in the simulated regolith. We report on the production and reaction rates of CO2 and CO, as well as the generation of free hydrogen and oxygen as detected by a SRS-100 mass spectrometer. We also identify residual products that either freeze on the surface or become entrained by or adsorbed onto the ice grains. We attempt to match the CO2 absorption feature found on Iapetus with that seen in our simulation, perhaps identifying a possible source of CO2 in the Saturnian system. Finally, we estimate the time required for these reactions to occur on Iapetus to see if UV photolysis would be effective.

Palmer, E. E.; Brown, R. H.

2008-12-01

72

Carbon dioxide conversion over carbon-based nanocatalysts.  

PubMed

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. PMID:23901504

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

2013-07-01

73

LIFETIME OF EXCESS ATMOSPHERIC CARBON DIOXIDE  

EPA Science Inventory

We explore the effects of a changing terrestrial biosphere on the atmospheric residende time of carbon dioxide using three simple ocean carbon cycling models and a model of global terrestrial carbon cycling. e find differences in model behavior associated with the assumption of a...

74

Carbon Dioxide Emission Factors for Coal  

EIA Publications

The Energy Information Administration (EIA) has developed factors for estimating the amount of carbon dioxide emitted, accounting for differences among coals, to reflect the changing "mix" of coal in U.S. coal consumption.

1994-01-01

75

Bench-to-bedside review: Carbon dioxide  

Microsoft Academic Search

Carbon dioxide is a waste product of aerobic cellular respiration in all aerobic life forms. PaCO2 represents the balance between the carbon dioxide produced and that eliminated. Hypocapnia remains a common - and generally\\u000a underappreciated - component of many disease states, including early asthma, high-altitude pulmonary edema, and acute lung\\u000a injury. Induction of hypocapnia remains a common, if controversial, practice

Gerard Curley; John G Laffey; Brian P Kavanagh

2010-01-01

76

4-110 Carbon dioxide flows through a pipe at a given state. The volume and mass flow rates and the density of CO2 at the given state and the volume flow rate at the exit of the pipe are to be determined.  

E-print Network

4-61 4-110 Carbon dioxide flows through a pipe at a given state. The volume and mass flow rates and the density of CO2 at the given state and the volume flow rate at the exit of the pipe are to be determined. Analysis (a) The volume and mass flow rates may be determined from ideal gas relation as 3 MPa 500 K 0

Bahrami, Majid

77

Mineralization strategies for carbon dioxide sequestration  

SciTech Connect

Progress is reported in three primary research areas--each concerned with sequestering carbon dioxide into mineral matrices. Direct mineral carbonation was pioneered at Albany Research Center. The method treats the reactant, olivine or serpentine in aqueous media with carbon dioxide at high temperature and pressure to form stable mineral carbonates. Recent results are introduced for pretreatment by high-intensity grinding to improve carbonation efficiency. To prove feasibility of the carbonation process, a new reactor was designed and operated to progress from batch tests to continuous operation. The new reactor is a prototype high-temperature, high-pressure flow loop reactor that will furnish information on flow, energy consumption, and wear and corrosion resulting from slurry flow and the carbonation reaction. A promising alternative mineralization approach is also described. New data are presented for long-term exposure of carbon dioxide to Colombia River Basalt to determine the extent of conversion of carbon dioxide to permanent mineral carbonates. Batch autoclave tests were conducted using drill-core samples of basalt and reacted under conditions that simulate in situ injection into basalt-containing geological formations.

Penner, Larry R.; O'Connor, William K.; Gerdemann, Stephen J.; Dahlin, David C.

2003-01-01

78

Atmospheric Lifetime of Fossil Fuel Carbon Dioxide  

E-print Network

Atmospheric Lifetime of Fossil Fuel Carbon Dioxide David Archer,1 Michael Eby,2 Victor Brovkin,3 released from combustion of fossil fuels equilibrates among the various carbon reservoirs of the atmosphere literature on the atmospheric lifetime of fossil fuel CO2 and its impact on climate, and we present initial

Scherer, Norbert F.

79

Where in the World is Carbon Dioxide?  

NSDL National Science Digital Library

This three part activity has students set up experiments to help them better understand the atmospheric portion of the carbon cycle. From this activity, they will be able to explain the concept of sources and sinks as they relate to carbon dioxide, the use of indicator solution bromothymol blue (BTB) to reveal the presence of carbon dioxide, and the qualitative differences between animal and fossil fuel sources of global carbon dioxide. The student guide has an overall description of all three parts of the activity, lists of materials, the procedure and observations and questions. The instructor guide contains detailed background material, learning goals, alignment to national standards, grade level/time, details on materials and preparation, procedure, assessment ideas, and modifications for alternative learners.

80

Carbon dioxide warming of the early Earth  

NASA Technical Reports Server (NTRS)

Svante Arrhenius' research in atmospheric physics extended beyond the recent past and the near future states of the Earth, which today are at the center of sociopolitical attention. His plan encompassed all of the physical phenomena known at the time to relate to the formation and evolution of stars and planets. His two-volume textbook on cosmic physics is a comprehensive synopsis of the field. The inquiry into the possible cause of the ice ages and the theory of selective wavelength filter control led Arrhenius to consider the surface states of the other terrestrial planets, and of the ancient Earth before it had been modified by the emergence of life. The rapid escape of hydrogen and the equilibration with igneous rocks required that carbon in the early atmosphere prevailed mainly in oxidized form as carbon dioxide, together with other photoactive gases exerting a greenhouse effect orders of magnitude larger than in our present atmosphere. This effect, together with the ensuing chemical processes, would have set the conditions for life to evolve on our planet, seeded from spores spreading through an infinite Universe, and propelled, as Arrhenius thought, by stellar radiation pressure.

Arrhenius, G.

1997-01-01

81

Carbon dioxide warming of the early Earth.  

PubMed

Svante Arrhenius' research in atmospheric physics extended beyond the recent past and the near future states of the Earth, which today are at the center of sociopolitical attention. His plan encompassed all of the physical phenomena known at the time to relate to the formation and evolution of stars and planets. His two-volume textbook on cosmic physics is a comprehensive synopsis of the field. The inquiry into the possible cause of the ice ages and the theory of selective wavelength filter control led Arrhenius to consider the surface states of the other terrestrial planets, and of the ancient Earth before it had been modified by the emergence of life. The rapid escape of hydrogen and the equilibration with igneous rocks required that carbon in the early atmosphere prevailed mainly in oxidized form as carbon dioxide, together with other photoactive gases exerting a greenhouse effect orders of magnitude larger than in our present atmosphere. This effect, together with the ensuing chemical processes, would have set the conditions for life to evolve on our planet, seeded from spores spreading through an infinite Universe, and propelled, as Arrhenius thought, by stellar radiation pressure. PMID:11541253

Arrhenius, G

1997-02-01

82

[An autopsy case of carbon dioxide intoxication].  

PubMed

A 44-year-old male, engaged in the transportation of dry ice, was found dead on the floor of the freezer of his refrigerator car which was parked in front of the place where he was scheduled to make a delivery. Autopsy was performed to investigate the cause of death. Apart from the signs of acute death, no other significant findings were obtained, either macro or microscopically; carbon dioxide poisoning was thus strongly suspected. We created a simulation experiment by using the refrigerator car to reproduce the events of the accident. The oxygen concentration in the freezer was 21.0% as indicated by oxygen sensors, but decreased to 17.1-17.4% when the engine was stopped. This decrease in oxygen concentration supposedly results from the production of carbon dioxide by the vaporization of dry ice. Carbon dioxide concentration in the air could be calculated from the change in the oxygen concentration in the closed space of the freezer. The concentration was assessed at 17.1-18.6%. An oxygen concentration of 17.1-17.4% does not of itself cause serious hypoxia, but a carbon dioxide concentration of 17.1-18.6% probably causes serious intoxication, because this value is beyond that of intoxication levels published in references. Therefore, we concluded that the cause of death in this case was carbon dioxide intoxication. PMID:9545760

Yamazaki, M; Islam, M N; Ogura, Y; Honda, K; Tsuchihashi, H; Nishioka, H

1997-12-01

83

Designed amyloid fibers as materials for selective carbon dioxide capture  

PubMed Central

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

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

2014-01-01

84

SEQUESTERING CARBON DIOXIDE IN COALBEDS  

SciTech Connect

The authors' long-term goal is to develop accurate prediction methods for describing the adsorption behavior of gas mixtures on solid adsorbents over complete ranges of temperature, pressure, and adsorbent types. The originally-stated, major objectives of the current project are to: (1) measure the adsorption behavior of pure CO{sub 2}, methane, nitrogen, and their binary and ternary mixtures on several selected coals having different properties at temperatures and pressures applicable to the particular coals being studied, (2) generalize the adsorption results in terms of appropriate properties of the coals to facilitate estimation of adsorption behavior for coals other than those studied experimentally, (3) delineate the sensitivity of the competitive adsorption of CO{sub 2}, methane, and nitrogen to the specific characteristics of the coal on which they are adsorbed; establish the major differences (if any) in the nature of this competitive adsorption on different coals, and (4) test and/or develop theoretically-based mathematical models to represent accurately the adsorption behavior of mixtures of the type for which measurements are made. As this project developed, an important additional objective was added to the above original list. Namely, we were encouraged to interact with industry and/or governmental agencies to utilize our expertise to advance the state of the art in coalbed adsorption science and technology. As a result of this additional objective, we participated with the Department of Energy and industry in the measurement and analysis of adsorption behavior as part of two distinct investigations. These include (a) Advanced Resources International (ARI) DOE Project DE-FC26-00NT40924, ''Adsorption of Pure Methane, Nitrogen, and Carbon Dioxide and Their Mixtures on Wet Tiffany Coal'', and (b) the DOE-NETL Project, ''Round Robin: CO{sub 2} Adsorption on Selected Coals''. These activities, contributing directly to the DOE projects listed above, also provided direct synergism with the original goals of our work. Specific accomplishments of this project are summarized below in three broad categories: experimentation, model development, and coal characterization.

K.A.M. Gasem; R.L. Robinson, Jr.; J.E. Fitzgerald; Z. Pan; M. Sudibandriyo

2003-04-30

85

SEQUESTERING CARBON DIOXIDE IN COALBEDS  

SciTech Connect

The authors' long-term goal is to develop accurate prediction methods for describing the adsorption behavior of gas mixtures on solid adsorbents over complete ranges of temperature, pressure and adsorbent types. The originally-stated, major objectives of the current project are to (1) measure the adsorption behavior of pure CO{sub 2}, methane, nitrogen, and their binary and ternary mixtures on several selected coals having different properties at temperatures and pressures applicable to the particular coals being studied, (2) generalize the adsorption results in terms of appropriate properties of the coals to facilitate estimation of adsorption behavior for coals other than those studied experimentally, (3) delineate the sensitivity of the competitive adsorption of CO{sub 2}, methane and nitrogen to the specific characteristics of the coal on which they are adsorbed; establish the major differences (if any) in the nature of this competitive adsorption on different coals, and (4) test and/or develop theoretically-based mathematical models to represent accurately the adsorption behavior of mixtures of the type for which measurements are made. As this project has developed, an important additional objective has been added to the above original list. Namely, we have been encouraged to interact with industry and/or governmental agencies to utilize our expertise to advance the state of the art in coalbed adsorption science and technology. As a result of this additional objective, we have participated with the Department of Energy and industry in the measurement and analysis of adsorption behavior as part of two distinct investigations. These include (a) Advanced Resources International (ARI) DOE Project DE-FC26-00NT40924, ''Adsorption of Pure Methane, Nitrogen, and Carbon Dioxide and Their Mixtures on Wet Tiffany Coal'', and (b) the DOE-NETL Project, ''Round Robin: CO{sub 2} Adsorption on Selected Coals''. These activities, contributing directly to the DOE projects listed above, have also provided direct synergism with the original goals of our work. Specific accomplishments of this project during the current reporting period are summarized in three broad categories outlining experimentation, model development, and coal characterization.

K.A.M. Gasem; R.L. Robinson, Jr.; L.R. Radovic

2003-03-10

86

Global deforestation: contribution to atmospheric carbon dioxide  

Microsoft Academic Search

A study of effects of terrestrial biota on the amount of carbon dioxide in the atmosphere suggests that the global net release of carbon due to forest clearing between 1960 and 1980 was between 135 X 10¹⁵ and 228 X 10¹⁵ grams. Between 1.8 X 10¹⁵ and 4.7 X 10¹⁵ grams of carbon were released in 1980, of which nearly

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

1983-01-01

87

Polymers for metal extractions in carbon dioxide  

DOEpatents

A composition useful for the extraction of metals and metalloids comprises (a) carbon dioxide fluid (preferably liquid or supercritical carbon dioxide); and (b) a polymer in the carbon dioxide, the polymer having bound thereto a ligand that binds the metal or metalloid; with the ligand bound to the polymer at a plurality of locations along the chain length thereof (i.e., a plurality of ligands are bound at a plurality of locations along the chain length of the polymer). The polymer is preferably a copolymer, and the polymer is preferably a fluoropolymer such as a fluoroacrylate polymer. The extraction method comprises the steps of contacting a first composition containing a metal or metalloid to be extracted with a second composition, the second composition being as described above; and then extracting the metal or metalloid from the first composition into the second composition.

DeSimone, Joseph M. (7315 Crescent Ridge Dr., Chapel Hill, NC 27516); Tumas, William (1130 Big Rock Loop, Los Alamos, NM 87544); Powell, Kimberly R. (103 Timber Hollow Ct. Apartment 323, Chapel Hill, NC 27514); McCleskey, T. Mark (1930 Camino Mora, Los Alamos, NM 87544); Romack, Timothy J. (5810 Forest Ridge Dr., Durham, NC 27713); McClain, James B. (8530 Sommersweet La., Raleigh, NC 27612); Birnbaum, Eva R. (1930 Camino Mora, Los Alamos, NM 87544)

2001-01-01

88

Do Plants Really Use Carbon Dioxide?  

NSDL National Science Digital Library

This experiment demonstrates that plants use carbon dioxide during photosynthesis. Four Teaching Tanks (commercially available, narrow tanks) are filled with water and bromthymol blue indicator, and Elodea plants are added to two of the tanks. Blowing through a straw into each tank dissolves carbon dioxide into the water and turns the indicator yellow. The tanks are sealed with clay, and a pair of tanksone tank with Elodea and one withoutis put in sunlight, while the other pair is put in darkness. After an hour, the tank with Elodea in sunlight will have returned to blue color. Learners can infer that the carbon dioxide in that tank has been used by the Elodea, since the water in "control" tanks remains yellow. Though designed as a demonstration, this activity could be adapted to allow varying degrees of learner hands-on involvement, and higher grade learners could potentially do all the steps without a demonstrator.

American Educational Products

1992-01-01

89

Carbon Dioxide Information Analysis Center (CDIAC)  

NSDL National Science Digital Library

Based at Oak Ridge National Laboratories in Tennessee, this Website is the US Department of Energy's "primary global-change data and information analysis center" and is a central source for many Carbon Dioxide-related resources. Among those resources are several we have reviewed, for example, the Catalog of Databases and Reports (reviewed in the June 24, 1998 Scout Report for Science & Engineering) and Carbon Dioxide Emission Estimates (reviewed in the March 4, 1998 Scout Report for Science & Engineering). The CDIAC site offers a wealth of information, including "records of the concentrations of carbon dioxide and other radiatively active gases in the atmosphere; the role of the terrestrial biosphere and the oceans in the biogeochemical cycles of greenhouse gases; emissions of carbon dioxide to the atmosphere; long-term climate trends; the effects of elevated carbon dioxide on vegetation; and the vulnerability of coastal areas to rising sea level." To get a feel for the research summaries and data available at the CDIAC site, see the Products section (describes the research projects associated with CDIAC as well as links to those data sets); the New section (offers a hyperlinked list of new data products); the Top 10 section (offers a hyperlinked list of Frequently Requested Global Change Products); or any of the specific project sections: FACE (Free Air CO2 Enrichment), NARSTO (a non-binding, tri-national, public/private alliance), OCEANS (Survey of CO2 in the Oceans), or AmeriFlux (long-term CO2 flux measurements of the Americas). This is an outstanding resource for those seeking global data (or research summaries) on the status of carbon dioxide in several components of the earth's ecosystems.

90

Master index for the carbon dioxide research state-of-the-art report series  

SciTech Connect

Four State of the Art (SOA) reports, ''Atmospheric Carbon Dioxide and the Global Carbon Cycle,'' ''Direct Effects of Increasing Carbon Dioxide on Vegetation,'' ''Detecting the Climatic Effects of Increasing Carbon Dioxide,'' and ''Projecting the Climatic Effects of Increasing Carbon Dioxide,'' and two companion reports, ''Characterization of Information Requirements for Studies of CO/sub 2/ Effects: Water Resources, Agriculture, Fisheries, Forests and Human Health'' and ''Glaciers, Ice Sheets, and Sea Level: Effect of a CO/sub 2/-Induced Climatic Change,'' were published by the US Department of Energy's Carbon Dioxide Research Division. Considerable information on atmospheric carbon dioxide and its possible effects on world climate is summarized in these six volumes. Each volume has its own index, but to make the information that is distributed throughout the six volumes more accessible and usable, comprehensive citation and subject indexes have been compiled. The subject indexes of the individual volumes have been edited to provide a uniformity from volume to volume and also to draw distinctions not needed in the separate volumes' indexes. Also, the comprehensive subject index has been formatted in a matrix arrangement to graphically show the distribution of subject treatment from volume to volume. Other aids include cross references between the scientific and common names of the animals and plants referred to, a glossary of special terms used, tables of data and conversion factors related to the data, and explanations of the acronyms and initialisms used in the texts of the six volumes. The executive summaries of the six volumes are collected and reproduced to allow the readers interested in the contents of one volume to rapidly gain information on the contents of the other volumes.

Farrell, M P [ed.

1987-03-01

91

Global deforestation: contribution to atmospheric carbon dioxide  

SciTech Connect

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

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

1983-12-09

92

International Space Station Carbon Dioxide Removal Assembly Testing  

NASA Technical Reports Server (NTRS)

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.

Knox, James C.

2000-01-01

93

Organic syntheses employing supercritical carbon dioxide as a reaction solvent  

NASA Technical Reports Server (NTRS)

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.

Barstow, Leon E. (Inventor); Ward, Glen D. (Inventor); Bier, Milan (Inventor)

1991-01-01

94

Carbon Dioxide-Water Emulsions for Enhanced Oil Recovery and Permanent Sequestration of Carbon Dioxide  

SciTech Connect

This project involves the use of an innovative new invention ? Particle Stabilized Emulsions (PSEs) of Carbon Dioxide-in-Water and Water-in-Carbon Dioxide for Enhanced Oil Recovery (EOR) and Permanent Sequestration of Carbon Dioxide. The EOR emulsion would be injected into a semi-depleted oil reservoir such as Dover 33 in Otsego County, Michigan. It is expected that the emulsion would dislocate the stranded heavy crude oil from the rock granule surfaces, reduce its viscosity, and increase its mobility. The advancing emulsion front should provide viscosity control which drives the reduced-viscosity oil toward the production wells. The make-up of the emulsion would be subsequently changed so it interacts with the surrounding rock minerals in order to enhance mineralization, thereby providing permanent sequestration of the injected CO{sub 2}. In Phase 1 of the project, the following tasks were accomplished: 1. Perform laboratory scale (mL/min) refinements on existing procedures for producing liquid carbon dioxide-in-water (C/W) and water-in-liquid carbon dioxide (W/C) emulsion stabilized by hydrophilic and hydrophobic fine particles, respectively, using a Kenics-type static mixer. 2. Design and cost evaluate scaled up (gal/min) C/W and W/C emulsification systems to be deployed in Phase 2 at the Otsego County semi-depleted oil field. 3. Design the modifications necessary to the present CO{sub 2} flooding system at Otsego County for emulsion injection. 4. Design monitoring and verification systems to be deployed in Phase 2 for measuring potential leakage of CO{sub 2} after emulsion injection. 5. Design production protocol to assess enhanced oil recovery with emulsion injection compared to present recovery with neat CO{sub 2} flooding. 6. Obtain Federal and State permits for emulsion injection. Initial research focused on creating particle stabilized emulsions with the smallest possible globule size so that the emulsion can penetrate even low-permeability crude oilcontaining formations or saline aquifers. The term ?globule? refers to the water or liquid carbon dioxide droplets sheathed with ultrafine particles dispersed in the continuous external medium, liquid CO{sub 2} or H{sub 2}O, respectively. The key to obtaining very small globules is the shear force acting on the two intermixing fluids, and the use of ultrafine stabilizing particles or nanoparticles. We found that using Kenics-type static mixers with a shear rate in the range of 2700 to 9800 s{sup -1} and nanoparticles between 100-300 nm produced globule sizes in the 10 to 20 ?m range. Particle stabilized emulsions with that kind of globule size should easily penetrate oil-bearing formations or saline aquifers where the pore and throat size can be on the order of 50 ?m or larger. Subsequent research focused on creating particle stabilized emulsions that are deemed particularly suitable for Permanent Sequestration of Carbon Dioxide. Based on a survey of the literature an emulsion consisting of 70% by volume of water, 30% by volume of liquid or supercritical carbon dioxide, and 2% by weight of finely pulverized limestone (CaCO{sub 3}) was selected as the most promising agent for permanent sequestration of CO{sub 2}. In order to assure penetration of the emulsion into tight formations of sandstone or other silicate rocks and carbonate or dolomite rock, it is necessary to use an emulsion consisting of the smallest possible globule size. In previous reports we described a high shear static mixer that can create such small globules. In addition to the high shear mixer, it is also necessary that the emulsion stabilizing particles be in the submicron size, preferably in the range of 0.1 to 0.2 ?m (100 to 200 nm) size. We found a commercial source of such pulverized limestone particles, in addition we purchased under this DOE Project a particle grinding apparatus that can provide particles in the desired size range. Additional work focused on attempts to generate particle stabilized emulsions with a flow through, static mixer based apparatus under a variety

Ryan, David; Golomb, Dan; Shi, Guang; Shih, Cherry; Lewczuk, Rob; Miksch, Joshua; Manmode, Rahul; Mulagapati, Srihariraju; Malepati, Chetankurmar

2011-09-30

95

U.S. Energy-Related Carbon Dioxide Emissions  

EIA Publications

U.S. Energy Information Administration releases its online analysis of 2012 energy-related carbon dioxide emissions today. It indicates U.S. carbon dioxide emissions from the consumption of fossil fuels were 5,290 million metric tons carbon dioxide in 2012, a decrease of almost 4% from the 2011 level. Energy-related carbon dioxide emissions have declined in five of the last seven years and are the lowest they have been since 1994.

2014-01-01

96

Discussion of Refrigeration Cycle Using Carbon Dioxide as Refrigerant  

NASA Astrophysics Data System (ADS)

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.

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

97

Carbon dioxide dynamics in an artificial ecosystem  

NASA Astrophysics Data System (ADS)

An experimental artificial ecosystem was established as a tool to understand the behavior of closed ecosystem and to develop the technology for a future bioregenerative life support system for lunar or planetary exploration. Total effective volume of the system is 0.7 m3 . It consists of a higher plant chamber, an animal chamber and a photo-bioreactor which cultivated lettuce (Lactuca sativa L.), silkworm (Bombyx Mori L.) and microalgae (Chlorella), respectively. For uniform and sustained observations, lettuce and silkworms was cultivated using sequential cultivation method, and microalgae using continuous culture. Four researchers took turns breathing the system air through a tube for brief periods every few hours. A mathematic model, simulating the carbon dioxide dynamics was developed. The main biological parameters concerning photosynthesis of lettuce and microalgae, respiration of silkworms and human were validated by the experimental data. The model described the respiratory relationship between autotrophic and heterotrophic compartments. A control strategy was proposed as a tool for the atmosphere management of the artificial ecosystem.

Hu, Enzhu; Hu, Dawei; Tong, Ling; Li, Ming; Fu, Yuming; He, Wenting; Liu, Hong

98

40 CFR 86.124-78 - Carbon dioxide analyzer calibration.  

Code of Federal Regulations, 2013 CFR

...2013-07-01 2013-07-01 false Carbon dioxide analyzer calibration...Light-Duty Trucks and New Otto-Cycle Complete Heavy-Duty Vehicles...Procedures 86.124-78 Carbon dioxide analyzer calibration...monthly thereafter the NDIR carbon dioxide analyzer shall be...

2013-07-01

99

40 CFR 86.1324-84 - Carbon dioxide analyzer calibration.  

Code of Federal Regulations, 2010 CFR

...2010-07-01 2010-07-01 false Carbon dioxide analyzer calibration...Emission Regulations for New Otto-Cycle and Diesel Heavy-Duty Engines...Procedures 86.1324-84 Carbon dioxide analyzer calibration...monthly thereafter, the NDIR carbon dioxide analyzer shall be...

2010-07-01

100

40 CFR 86.124-78 - Carbon dioxide analyzer calibration.  

Code of Federal Regulations, 2010 CFR

...2010-07-01 2010-07-01 false Carbon dioxide analyzer calibration...Light-Duty Trucks and New Otto-Cycle Complete Heavy-Duty Vehicles...Procedures 86.124-78 Carbon dioxide analyzer calibration...monthly thereafter the NDIR carbon dioxide analyzer shall be...

2010-07-01

101

40 CFR 86.1324-84 - Carbon dioxide analyzer calibration.  

Code of Federal Regulations, 2013 CFR

...2013-07-01 2013-07-01 false Carbon dioxide analyzer calibration...Emission Regulations for New Otto-Cycle and Diesel Heavy-Duty Engines...Procedures 86.1324-84 Carbon dioxide analyzer calibration...monthly thereafter, the NDIR carbon dioxide analyzer shall be...

2013-07-01

102

40 CFR 86.124-78 - Carbon dioxide analyzer calibration.  

Code of Federal Regulations, 2012 CFR

...2012-07-01 2012-07-01 false Carbon dioxide analyzer calibration...Light-Duty Trucks and New Otto-Cycle Complete Heavy-Duty Vehicles...Procedures 86.124-78 Carbon dioxide analyzer calibration...monthly thereafter the NDIR carbon dioxide analyzer shall be...

2012-07-01

103

40 CFR 86.124-78 - Carbon dioxide analyzer calibration.  

Code of Federal Regulations, 2014 CFR

...2014-07-01 2014-07-01 false Carbon dioxide analyzer calibration...Light-Duty Trucks and New Otto-Cycle Complete Heavy-Duty Vehicles...Procedures 86.124-78 Carbon dioxide analyzer calibration...monthly thereafter the NDIR carbon dioxide analyzer shall be...

2014-07-01

104

40 CFR 86.1324-84 - Carbon dioxide analyzer calibration.  

Code of Federal Regulations, 2011 CFR

...2011-07-01 2011-07-01 false Carbon dioxide analyzer calibration...Emission Regulations for New Otto-Cycle and Diesel Heavy-Duty Engines...Procedures 86.1324-84 Carbon dioxide analyzer calibration...monthly thereafter, the NDIR carbon dioxide analyzer shall be...

2011-07-01

105

40 CFR 86.124-78 - Carbon dioxide analyzer calibration.  

Code of Federal Regulations, 2011 CFR

...2011-07-01 2011-07-01 false Carbon dioxide analyzer calibration...Light-Duty Trucks and New Otto-Cycle Complete Heavy-Duty Vehicles...Procedures 86.124-78 Carbon dioxide analyzer calibration...monthly thereafter the NDIR carbon dioxide analyzer shall be...

2011-07-01

106

40 CFR 86.1324-84 - Carbon dioxide analyzer calibration.  

Code of Federal Regulations, 2012 CFR

...2012-07-01 2012-07-01 false Carbon dioxide analyzer calibration...Emission Regulations for New Otto-Cycle and Diesel Heavy-Duty Engines...Procedures 86.1324-84 Carbon dioxide analyzer calibration...monthly thereafter, the NDIR carbon dioxide analyzer shall be...

2012-07-01

107

Chukwuemeka I. Okoye Carbon Dioxide Solubility and Absorption Rate in  

E-print Network

Copyright by Chukwuemeka I. Okoye 2005 #12;Carbon Dioxide Solubility and Absorption Rate _______________________ Nicholas A. Peppas #12;Carbon Dioxide Solubility and Absorption Rate in Monoethanolamine/Piperazine/H2O for. #12;iii Carbon Dioxide Solubility and Absorption Rate in Monoethanolamine/Piperazine/H2O

Rochelle, Gary T.

108

Designed amyloid fibers as materials for selective carbon dioxide capture  

E-print Network

Designed amyloid fibers as materials for selective carbon dioxide capture Dan Lia,b,c,1 , Hiroyasu 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

109

A Simple Model for Atmospheric Carbon Dioxide  

NSDL National Science Digital Library

In this problem set, learners will create and use a differential equation of rate-of-change of atmospheric carbon dioxide. They will refer to the "Keeling Curve" graph and information on the sources and sinks of carbon on Earth to create the equation and apply it to answer a series of questions. Answer key is provided. This is part of Earth Math: A Brief Mathematical Guide to Earth Science and Climate Change.

2012-08-03

110

RISING CARBON DIOXIDE AND WEED ECOLOGY  

Technology Transfer Automated Retrieval System (TEKTRAN)

Documented and projected changes in the concentration of atmospheric carbon dioxide [CO2] and other gases suggest potential changes in climate stability which could negatively impact human systems. One such system would involve negative impacts on agricultural crops and associated weeds. Climatic o...

111

21 CFR 582.1240 - Carbon dioxide.  

Code of Federal Regulations, 2010 CFR

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, FEEDS, AND RELATED PRODUCTS ? SUBSTANCES GENERALLY RECOGNIZED AS SAFE...

2010-04-01

112

21 CFR 582.1240 - Carbon dioxide.  

Code of Federal Regulations, 2012 CFR

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, FEEDS, AND RELATED PRODUCTS ? SUBSTANCES GENERALLY RECOGNIZED AS SAFE...

2012-04-01

113

21 CFR 582.1240 - Carbon dioxide.  

Code of Federal Regulations, 2011 CFR

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, FEEDS, AND RELATED PRODUCTS ? SUBSTANCES GENERALLY RECOGNIZED AS SAFE...

2011-04-01

114

21 CFR 582.1240 - Carbon dioxide.  

Code of Federal Regulations, 2014 CFR

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, FEEDS, AND RELATED PRODUCTS ? SUBSTANCES GENERALLY RECOGNIZED AS SAFE...

2014-04-01

115

Ocean Acidification: The Other Carbon Dioxide Problem  

NSDL National Science Digital Library

This NOAA video discusses how the ocean absorbs the increased amount of carbon dioxide released into the atmosphere, thereby changing the pH and buffering action of the ocean. These changes in pH are impacting calcifying organisms, such as corals and shellfish, and related food chains and ecosystems.

Noaa; Administration, National O.

116

Carbon Dioxide Corrosion: Modelling and Experimental Work  

E-print Network

Carbon Dioxide Corrosion: Modelling and Experimental Work Applied to Natural Gas Pipelines Philip in the corrosion related research institutions at IFE and the Ohio University or any other scientific research;#12;Introduction - v - Summary CO2 corrosion is a general problem in the industry and it is expensive. The focus

117

CDIAC: Carbon Dioxide Information Analysis Center  

NSDL National Science Digital Library

This site is the homepage of the Carbon Dioxide Information Analysis Center (CDIAC) which includes the World Data Center for Atmospheric Trace Gases. CDIAC is the primary global-change data and information analysis center of the U.S. Department of Energy (DOE). CDIAC responds to data and information requests from users from all over the world who are concerned with the greenhouse effect and global climate change. CDIAC's data holdings include records of the concentrations of carbon dioxide and other radiatively active gases in the atmosphere; the role of the terrestrial biosphere and the oceans in the biogeochemical cycles of greenhouse gases; emissions of carbon dioxide to the atmosphere; long-term climate trends; the effects of elevated carbon dioxide on vegetation; and the vulnerability of coastal areas to rising sea level. In operation since 1982, CDIAC: obtains, evaluates, and archives data, compiles and distributes digital numeric data packages and computer model packages, provides data management support to global-change related scientific projects, distributes related reports, produces the newsletter, CDIAC Communications, and in general acts as the information focus for the U.S. DOE Global Change Research Program. CDIAC is supported by DOE's Environmental Sciences Division of the Office of Biological and Environmental Research. CDIAC represents DOE in the multi-agency Global Change Data and Information System.

118

Atmospheric carbon dioxide record from Mauna Loa  

NSDL National Science Digital Library

The Scripps Institute of Oceanography has released these data consisting of monthly carbon dioxide concentrations at Mauna Loa 1958-1999. Measurements were made using a nondispersive infrared gas analyzer with a water vapor freeze trap. The data are available as graphs or tables. The text includes a brief overview of the methods and a reference list.

119

The Transport Properties of Carbon Dioxide  

Microsoft Academic Search

The paper contains new, representative equations for the viscosity and thermal conductivity of carbon dioxide. The equations are based in part upon a body of experimental data that have been critically assessed for internal consistency and for agreement with theory whenever possible. In the case of the low-density thermal conductivity at high temperatures, all available data are shown to be

V. Vesovic; W. A. Wakeham; G. A. Olchowy; J. V. Sengers; J. T. R. Watson; J. Millat

1990-01-01

120

Recent Events: a Perspective on Carbon Dioxide  

NSDL National Science Digital Library

In this problem set, learners will compare the carbon dioxide produced as a result of two 2010 events: the eruption of the Eyjafjalla Volcano and the burning of oil on the ocean surface to address the Gulf of Mexico oil spill. Answer key is provided. This is part of Earth Math: A Brief Mathematical Guide to Earth Science and Climate Change.

121

Inhalation of Carbon Dioxide at High Altitudes  

Microsoft Academic Search

THE suggestion put forward in NATURE of March 23 (p. 457) by Prof. Yandell Henderson and others to the effect that carbon dioxide might be of use in high altitude climbing reminds me of some trials carried out about ten years ago. Messrs. Siebe German and Co., Ltd., had similar ideas, and they lent me a rebreathing mask to try

P. J. H. Unna

1935-01-01

122

Carbon Dioxide Production at Home  

NSDL National Science Digital Library

In this problem set, learners will consider the "Carbon Footprint" of a family of four in a given context, as well as the US and global averages, and compare that with their own to answer a series of questions. They will use an online Carbon Footprint calculator to determine their own per-capita carbon production. Answer key is provided. This problem is part of Earth Math: A Brief Mathematical Guide to Earth Science and Climate Change.

2012-08-03

123

Dynamic solubility measurements of caffeine in carbon dioxide and in carbon dioxide saturated with water  

NASA Astrophysics Data System (ADS)

The solubility of caffeine in dry carbon dioxide has been measured between 310 and 430 K up to 70 MPa. The solubility of caffeine in carbon dioxide saturated with water has been measured between 303 and 363 K up to 30 MPa. The results can be reproduced by simple equations. These equations allow a calculation of the solubilities at higher and lower pressures. Using these equations, cross virial coefficients have been calculated for both systems.

Lentz, Harro; Gehrig, Manfred; Schulmeyer, Josef

1986-05-01

124

Coral, Carbon Dioxide and Calcification  

NSDL National Science Digital Library

In this group activity, learners act out key stages of the "ocean carbon cycle" (also known as the "carbonate buffer system") through motions, rearranging blocks and team tasks. Learners will also hypothesize the potential effects on the ocean and coral when variables are changed (e.g. the addition of massive amounts of CO2 and increased water temperature). At least 8 learners are needed to participate in the simulation. This detailed lesson plan includes an introduction, background information related to corals and the ocean carbon cycle, and adaptation suggestions for younger learners.

Stephanie L. Anderson

2012-07-17

125

Personal Carbon Dioxide Impact (title provided or enhanced by cataloger)  

NSDL National Science Digital Library

The amount of carbon dioxide in the atmosphere has been increasing for many decades now, mostly due to the burning of fossil fuels by mankind. In this exercise, students will track their daily activities, and and estimate how much carbon dioxide they are responsible for emitting with the use of an online Personal Greenhouse Gas Calculator developed by the U.S. Environmental Protection Agency (EPA). The calculator sums the carbon dioxide produced by driving, electricity use, and waste disposal, and provides an estimate of annual carbon dioxide emissions. It also allows users to see how changes in lifestyle could reduce carbon dioxide emissions. Links to websites with additional information are also provided.

Pratte, John

126

Carbon Dioxide Reduction Technology Trade Study  

NASA Technical Reports Server (NTRS)

For long-term human missions, a closed-loop atmosphere revitalization system (ARS) is essential to minimize consumables. A carbon dioxide (CO2) reduction technology is used to reclaim oxygen (O2) from metabolic CO2 and is vital to reduce the delivery mass of metabolic O2. A key step in closing the loop for ARS will include a proper CO2 reduction subsystem that is reliable and with low equivalent system mass (ESM). Sabatier and Bosch CO2 reduction are two traditional CO2 reduction subsystems (CRS). Although a Sabatier CRS has been delivered to International Space Station (ISS) and is an important step toward closing the ISS ARS loop, it recovers only 50% of the available O2 in CO2. A Bosch CRS is able to reclaim all O2 in CO2. However, due to continuous carbon deposition on the catalyst surface, the penalties of replacing spent catalysts and reactors and crew time in a Bosch CRS are significant. Recently, technologies have been developed for recovering hydrogen (H2) from Sabatier-product methane (CH4). These include methane pyrolysis using a microwave plasma, catalytic thermal pyrolysis of CH4 and thermal pyrolysis of CH4. Further, development in Sabatier reactor designs based on microchannel and microlith technology could open up opportunities in reducing system mass and enhancing system control. Improvements in Bosch CRS conversion have also been reported. In addition, co-electrolysis of steam and CO2 is a new technology that integrates oxygen generation and CO2 reduction functions in a single system. A co-electrolysis unit followed by either a Sabatier or a carbon formation reactor based on Bosch chemistry could improve the overall competitiveness of an integrated O2 generation and CO2 reduction subsystem. This study evaluates all these CO2 reduction technologies, conducts water mass balances for required external supply of water for 1-, 5- and 10-yr missions, evaluates mass, volume, power, cooling and resupply requirements of various technologies. A system analysis and comparison among the technologies was made based on ESM, technology readiness level and reliability. Those technologies with potential were recommended for development.

Jeng, Frank F.; Anderson, Molly S.; Abney, Morgan B.

2011-01-01

127

Development of a differential equation of state to describe subcritical isotherms of carbon dioxide  

E-print Network

below 273 K. Only authors whose works include subcritical results 24 Table 6. Experimental Studies of' the Single-Phase Density of Carbon Dioxide at Subcritical Temperatures Source Amagat (1893a, b) Antoine (1899) Keesom (1903) Jenkin (1920... (1869). Angus, S. , Armstrong, B. , de Reuck, K. M. , " International Thermodynamic Tables of the Fluid State, Volume 3 Carbon Dioxide, " Pergamon Press, Oxford (1976). Antoine, C. , Chem. Rev. , 108, 896 (1899). B H, U. , ~41 . Pd ~ 3 (4) 733 (1906...

Fontenot, Charles Edward

2012-06-07

128

Transport of Carbon Dioxide and Radioactive Waste  

Microsoft Academic Search

\\u000a A comparative assessment of carbon dioxide (CO2) and radioactive waste transport systems associated with electricity generation was undertaken on the basis of 15 criteria\\u000a grouped under three areas, namely the transport chain, policy aspects and state of the technology. For CO2, we considered exclusively the transport that would take place under a future large-scale capture and storage infrastructure.\\u000a Our study

Daro R. Gmez; Michael Tyacke

129

Solubility of triacylglycerols in supercritical carbon dioxide  

Microsoft Academic Search

The solubility of refined corn and sunflower seed oils, babassu (Attalea funifera) and ucuuba (Virola sebifera) fats in supercritical carbon dioxide (SC-CO2) were measured in a temperature range from 40 to 80C and pressure between 200 and 350bar. Under working conditions, the values of solubility showed retrograde behavior. Experimental SC-CO2 solubility data were collected from the literature for the following

B. M. C. Soares; F. M. C. Gamarra; L. C. Paviani; L. A. G. Gonalves; F. A. Cabral

2007-01-01

130

Electrochemical carbon dioxide concentrator: Math model  

NASA Technical Reports Server (NTRS)

A steady state computer simulation model of an Electrochemical Depolarized Carbon Dioxide Concentrator (EDC) has been developed. The mathematical model combines EDC heat and mass balance equations with empirical correlations derived from experimental data to describe EDC performance as a function of the operating parameters involved. The model is capable of accurately predicting performance over EDC operating ranges. Model simulation results agree with the experimental data obtained over the prediction range.

Marshall, R. D.; Schubert, F. H.; Carlson, J. N.

1973-01-01

131

Carbon dioxide in Arctic and subarctic regions  

SciTech Connect

A three year research project was presented that would define the role of the Arctic ocean, sea ice, tundra, taiga, high latitude ponds and lakes and polar anthropogenic activity on the carbon dioxide content of the atmosphere. Due to the large physical and geographical differences between the two polar regions, a comparison of CO/sub 2/ source and sink strengths of the two areas was proposed. Research opportunities during the first year, particularly those aboard the Swedish icebreaker, YMER, provided additional confirmatory data about the natural source and sink strengths for carbon dioxide in the Arctic regions. As a result, the hypothesis that these natural sources and sinks are strong enough to significantly affect global atmospheric carbon dioxide levels is considerably strengthened. Based on the available data we calculate that the whole Arctic region is a net annual sink for about 1.1 x 10/sup 15/ g of CO/sub 2/, or the equivalent of about 5% of the annual anthropogenic input into the atmosphere. For the second year of this research effort, research on the seasonal sources and sinks of CO/sub 2/ in the Arctic will be continued. Particular attention will be paid to the seasonal sea ice zones during the freeze and thaw periods, and the tundra-taiga regions, also during the freeze and thaw periods.

Gosink, T. A.; Kelley, J. J.

1981-03-01

132

Carbon dioxide reduction by the Bosch process  

NASA Technical Reports Server (NTRS)

Prototype units for carrying out the reduction of carbon dioxide to elementary carbon have been built and operated successfully. In some cases, however, startup difficulties have been reported. Moreover, the recycle reactor product has been reported to contain only small amounts of water and undesirably high yields of methane. This paper presents the results of the first phase of an experimental study that was carried out to define the mechanisms occurring in the reduction process. Conclusions are drawn and possible modifications to the present recycle process are suggested.

Manning, M. P.; Reid, R. C.

1975-01-01

133

Carbon Dioxide Aquariums Greenhouse Gas Lesson  

NSDL National Science Digital Library

This classroom activity looks at carbon dioxide and its role in climate change. Students will perform an in-class experiment using aquariums. CO2 gas will be added to one aquarium, and measurements are taken of both aquariums over a one or two week period. This lesson includes step by step instructions on carrying out the experiment. The unit is a good introduction to the concepts of the carbon cycle, heat transfer, energy flow in ecosystems, the human impact on ecosystems and climate, non-renewable energy, resource consumption and pollution. This document may be downloaded in PDF file format. A class worksheet is included with the document.

Orzali, Joe

2009-01-01

134

Carbon dioxide sensitivity of zeolitic imidazolate frameworks.  

PubMed

Zeolitic imidazolate frameworks of zinc, cobalt, and cadmium, including the framework ZIF-8 commercially sold as Basolite Z1200, exhibit surprising sensitivity to carbon dioxide under mild conditions. The frameworks chemically react with CO2 in the presence of moisture or liquid water to form carbonates. This effect, which has been previously not reported in metal-organic framework chemistry, provides an explanation for conflicting reports on ZIF-8 stability to water and is of outstanding significance for evaluating the potential applications of metal-organic frameworks, especially for CO2 sequestration. PMID:24889776

Mottillo, Cristina; Fri?i?, Tomislav

2014-07-14

135

Elevated atmospheric carbon dioxide increases soil carbon  

SciTech Connect

In a study funded by the U.S. Department of Energy's Office of Science, researchers from Argonne and Oak Ridge National Laboratories and Kansas State and Texas A&M Universities evaluated the collective results of earlier studies by using a statistical procedure called meta-analysis. They found that on average elevated CO2 increased soil carbon by 5.6 percent over a two to nine year period. They also measured comparable increases in soil carbon for Tennessee deciduous forest and Kansas grassland after five to eight years of experimental exposure to elevated CO2.

Norby, Richard J [ORNL; Jastrow, Julie D [ORNL; Miller, Michael R [ORNL; Matamala, Roser [Argonne National Laboratory (ANL); Boutton, Thomas W [Texas A& M University; Rice, Charles W [ORNL; Owensby, Clenton E [Kansas State University

2005-01-01

136

Effect of carbon dioxide in carbonated drinks on linguapalatal swallowing pressure.  

PubMed

This study aimed to investigate the influence of carbonated drinks with gas volumes (GV) of 0, 1.5, and 2.7 on linguapalatal swallowing pressure, intraoral carbonation perception, and maximum velocity of a bolus through the pharynx in healthy volunteers (N = 20, all female, age range; 20-21 years). The volunteers swallowed a 12-mL drink in the natural state. Linguapalatal swallowing pressure was measured using a special sensor sheet, and maximum velocity of the bolus through the pharynx was measured using ultrasonic diagnostic imaging equipment. Peak magnitude, integrated value, and duration of linguapalatal swallowing pressure and maximum velocity of a liquid bolus through the pharynx increased with an increase in carbon dioxide content in the carbonated drink. The total integrated values of carbonated drinks with GV of 1.5 and 2.7 were larger than that of the drink without carbon dioxide. These results suggest that the carbon dioxide dissolved in carbonated drinks influences the activity of taste receptors in the mouth and results in neuromotor responses. PMID:24302689

Moritaka, Hatsue; Kitade, Masami; Sawamura, Shin-ichi; Takihara, Takanobu; Awano, Izumi; Ono, Takahiro; Tamine, Kenichi; Hori, Kazuhiro

2014-02-01

137

A high-pressure carbon dioxide gasdynamic laser  

NASA Technical Reports Server (NTRS)

A carbon dioxide gasdynamic laser was operated over a range of reservoir pressure and temperature, test-gas mixture, and nozzle geometry. A significant result is the dominant influence of nozzle geometry on laser power at high pressure. High reservoir pressure can be effectively utilized to increase laser power if nozzle geometry is chosen to efficiently freeze the test gas. Maximum power density increased from 3.3 W/cu cm of optical cavity volume for an inefficient nozzle to 83.4 W/cu cm at 115 atm for a more efficient nozzle. Variation in the composition of the test gas also caused large changes in laser power output. Most notable is the influence of the catalyst (helium or water vapor) that was used to depopulate the lower vibrational state of the carbon dioxide. Water caused an extreme deterioration of laser power at high pressure (100 atm), whereas, at low pressure the laser for the two catalysts approached similar values. It appears that at high pressure the depopulation of the upper laser level of the carbon dioxide by the water predominates over the lower state depopulation, thus destroying the inversion.

Kuehn, D. M.

1973-01-01

138

Irreversible climate change due to carbon dioxide emissions.  

PubMed

The severity of damaging human-induced climate change depends not only on the magnitude of the change but also on the potential for irreversibility. This paper shows that the climate change that takes place due to increases in carbon dioxide concentration is largely irreversible for 1,000 years after emissions stop. Following cessation of emissions, removal of atmospheric carbon dioxide decreases radiative forcing, but is largely compensated by slower loss of heat to the ocean, so that atmospheric temperatures do not drop significantly for at least 1,000 years. Among illustrative irreversible impacts that should be expected if atmospheric carbon dioxide concentrations increase from current levels near 385 parts per million by volume (ppmv) to a peak of 450-600 ppmv over the coming century are irreversible dry-season rainfall reductions in several regions comparable to those of the "dust bowl" era and inexorable sea level rise. Thermal expansion of the warming ocean provides a conservative lower limit to irreversible global average sea level rise of at least 0.4-1.0 m if 21st century CO(2) concentrations exceed 600 ppmv and 0.6-1.9 m for peak CO(2) concentrations exceeding approximately 1,000 ppmv. Additional contributions from glaciers and ice sheet contributions to future sea level rise are uncertain but may equal or exceed several meters over the next millennium or longer. PMID:19179281

Solomon, Susan; Plattner, Gian-Kasper; Knutti, Reto; Friedlingstein, Pierre

2009-02-10

139

Atmospheric Carbon Dioxide and Carbon Reservoir Changes  

Microsoft Academic Search

The net release of CO2 from the biosphere to the atmosphere between 1850 and 1950 is estimated to amount to 1.2 109 tons of carbon per year. During this interval, changes in land use reduced the total terrestrial biomass by 7 percent. There has been a smaller reduction in biomass over the last few decades. In the middle 19th

Minze Stuiver

1978-01-01

140

Carbon dioxide disposal in carbonate minerals  

Microsoft Academic Search

We introduce a safe and permanent method of CO2 disposal based on combining CO2 chemically with abundant raw materials to form stable carbonate minerals. Substantial heat is liberated in the overall chemical reaction so that cost will be determined by the simplicity and speed of the reaction rather than the cost of energy. Preliminary investigations have been conducted on two

Klaus S. Lackner; Christopher H. Wendt; Darryl P. Butt; Edward L. Joyce; David H. Sharp

1995-01-01

141

Elevated atmospheric carbon dioxide increases soil carbon  

Microsoft Academic Search

In a study funded by the U.S. Department of Energy's Office of Science, researchers from Argonne and Oak Ridge National Laboratories and Kansas State and Texas A&M Universities evaluated the collective results of earlier studies by using a statistical procedure called meta-analysis. They found that on average elevated CO2 increased soil carbon by 5.6 percent over a two to nine

Richard J Norby; Michael R Miller; Roser Matamala; THOMAS W. BOUTTON; CHARLES W. RICE; CLENTON E. OWENSBY

2005-01-01

142

Automated carbon dioxide cleaning system  

NASA Technical Reports Server (NTRS)

Solidified CO2 pellets are an effective blast media for the cleaning of a variety of materials. CO2 is obtained from the waste gas streams generated from other manufacturing processes and therefore does not contribute to the greenhouse effect, depletion of the ozone layer, or the environmental burden of hazardous waste disposal. The system is capable of removing as much as 90 percent of the contamination from a surface in one pass or to a high cleanliness level after multiple passes. Although the system is packaged and designed for manual hand held cleaning processes, the nozzle can easily be attached to the end effector of a robot for automated cleaning of predefined and known geometries. Specific tailoring of cleaning parameters are required to optimize the process for each individual geometry. Using optimum cleaning parameters the CO2 systems were shown to be capable of cleaning to molecular levels below 0.7 mg/sq ft. The systems were effective for removing a variety of contaminants such as lubricating oils, cutting oils, grease, alcohol residue, biological films, and silicone. The system was effective on steel, aluminum, and carbon phenolic substrates.

Hoppe, David T.

1991-01-01

143

Carbon dioxide: A substitute for phosgene  

SciTech Connect

One of the many goals of the green chemistry movement is to eliminate the use of phosgene (COCl{sub 2}), an extremely hazardous compound used in many syntheses, including the production of carbamates, organic carbonates, and polymers. One of the most interesting options for eliminating this compound is to replace it with CO{sub 2}. In addition to carbon dioxide`s abundance and benign nature, it has the benefits of recycling carbon and of reducing the amount of CO{sub 2} released into the atmosphere when its use is linked with other processes that emit CO{sub 2}. Several synthetic strategies that do not use phosgene are under development. The authors briefly review the most interesting ones and then expand on the use of CO{sub 2} as a potential building block for organic carbamates, carbonates, and isocyanates. One of these routes, polycarbonate synthesis, is already in industrial-scale operation: PAC Polymers Inc. currently produces CO{sub 2}-epoxide copolymers. The synthesis of carbamates and substituted ureas has been developed, and this process awaits industrial exploitation.

Aresta, M.; Quaranta, E. [Univ. of Bari (Italy)

1997-03-01

144

Carbon Dioxide Transport through Membranes*  

PubMed Central

Several membrane channels, like aquaporin-1 (AQP1) and the RhAG protein of the rhesus complex, were hypothesized to be of physiological relevance for CO2 transport. However, the underlying assumption that the lipid matrix imposes a significant barrier to CO2 diffusion was never confirmed experimentally. Here we have monitored transmembrane CO2 flux (JCO2) by imposing a CO2 concentration gradient across planar lipid bilayers and detecting the resulting small pH shift in the immediate membrane vicinity. An analytical model, which accounts for the presence of both carbonic anhydrase and buffer molecules, was fitted to the experimental pH profiles using inverse problems techniques. At pH 7.4, the model revealed that JCO2 was entirely rate-limited by near-membrane unstirred layers (USL), which act as diffusional barriers in series with the membrane. Membrane tightening by sphingomyelin and cholesterol did not alter JCO2 confirming that membrane resistance was comparatively small. In contrast, a pH-induced shift of the CO2 hydration-dehydration equilibrium resulted in a relative membrane contribution of about 15% to the total resistance (pH 9.6). Under these conditions, a membrane CO2 permeability (3.2 1.6 cm/s) was estimated. It indicates that cellular CO2 uptake (pH 7.4) is always USL-limited, because the USL size always exceeds 1 ?m. Consequently, facilitation of CO2 transport by AQP1, RhAG, or any other protein is highly unlikely. The conclusion was confirmed by the observation that CO2 permeability of epithelial cell monolayers was always the same whether AQP1 was overexpressed in both the apical and basolateral membranes or not. PMID:18617525

Missner, Andreas; Kgler, Philipp; Saparov, Sapar M.; Sommer, Klaus; Mathai, John C.; Zeidel, Mark L.; Pohl, Peter

2008-01-01

145

Carbon dioxide and water vapor high temperature electrolysis  

NASA Technical Reports Server (NTRS)

The design, fabrication, breadboard testing, and the data base obtained for solid oxide electrolysis systems that have applications for planetary manned missions and habitats are reviewed. The breadboard tested contains sixteen tubular cells in a closely packed bundle for the electrolysis of carbon dioxide and water vapor. The discussion covers energy requirements, volume, weight, and operational characteristics related to the measurement of the reactant and product gas compositions, temperature distribution along the electrolyzer tubular cells and through the bundle, and thermal energy losses. The reliability of individual cell performance in the bundle configuration is assessed.

Isenberg, Arnold O.; Verostko, Charles E.

1989-01-01

146

Carbon dioxide sensor. [partial pressure measurement using monochromators  

NASA Technical Reports Server (NTRS)

Analytical techniques for measuring CO2 were evaluated and rated for use with the advanced extravehicular mobility unit. An infrared absorption concept using a dual-wavelength monochromator was selected for investigation. A breadboard carbon dioxide sensor (CDS) was assembled and tested. The CDS performance showed the capability of measuring CO2 over the range of 0 to 4.0 kPa (0 to 30 mmHg) P sub (CO2). The volume and weight of a flight configured CDS should be acceptable. It is recommended that development continue to complete the design of a flight prototype.

1975-01-01

147

Robust carbon dioxide reduction on molybdenum disulphide edges.  

PubMed

Electrochemical reduction of carbon dioxide has been recognized as an efficient way to convert carbon dioxide to energy-rich products. Noble metals (for example, gold and silver) have been demonstrated to reduce carbon dioxide at moderate rates and low overpotentials. Nevertheless, the development of inexpensive systems with an efficient carbon dioxide reduction capability remains a challenge. Here we identify molybdenum disulphide as a promising cost-effective substitute for noble metal catalysts. We uncover that molybdenum disulphide shows superior carbon dioxide reduction performance compared with the noble metals with a high current density and low overpotential (54?mV) in an ionic liquid. Scanning transmission electron microscopy analysis and first principle modelling reveal that the molybdenum-terminated edges of molybdenum disulphide are mainly responsible for its catalytic performance due to their metallic character and a high d-electron density. This is further experimentally supported by the carbon dioxide reduction performance of vertically aligned molybdenum disulphide. PMID:25073814

Asadi, Mohammad; Kumar, Bijandra; Behranginia, Amirhossein; Rosen, Brian A; Baskin, Artem; Repnin, Nikita; Pisasale, Davide; Phillips, Patrick; Zhu, Wei; Haasch, Richard; Klie, Robert F; Krl, Petr; Abiade, Jeremiah; Salehi-Khojin, Amin

2014-01-01

148

Effects of carbon dioxide on Penicillium chrysogenum: an autoradiographic study  

SciTech Connect

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

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

1988-06-20

149

Robust carbon dioxide reduction on molybdenum disulphide edges  

NASA Astrophysics Data System (ADS)

Electrochemical reduction of carbon dioxide has been recognized as an efficient way to convert carbon dioxide to energy-rich products. Noble metals (for example, gold and silver) have been demonstrated to reduce carbon dioxide at moderate rates and low overpotentials. Nevertheless, the development of inexpensive systems with an efficient carbon dioxide reduction capability remains a challenge. Here we identify molybdenum disulphide as a promising cost-effective substitute for noble metal catalysts. We uncover that molybdenum disulphide shows superior carbon dioxide reduction performance compared with the noble metals with a high current density and low overpotential (54?mV) in an ionic liquid. Scanning transmission electron microscopy analysis and first principle modelling reveal that the molybdenum-terminated edges of molybdenum disulphide are mainly responsible for its catalytic performance due to their metallic character and a high d-electron density. This is further experimentally supported by the carbon dioxide reduction performance of vertically aligned molybdenum disulphide.

Asadi, Mohammad; Kumar, Bijandra; Behranginia, Amirhossein; Rosen, Brian A.; Baskin, Artem; Repnin, Nikita; Pisasale, Davide; Phillips, Patrick; Zhu, Wei; Haasch, Richard; Klie, Robert F.; Krl, Petr; Abiade, Jeremiah; Salehi-Khojin, Amin

2014-07-01

150

Enriching blast furnace gas by removing carbon dioxide.  

PubMed

Blast furnace gas (BF gas) produced in the iron making process is an essential energy resource for a steel making work. As compared with coke oven gas, the caloric value of BF gas is too low to be used alone as fuel in hot stove because of its high concentrations of carbon dioxide and nitrogen. If the carbon dioxide in BF gas could be captured efficiently, it would meet the increasing need of high caloric BF gas, and develop methods to reusing and/or recycling the separated carbon dioxide further. Focused on this, investigations were done with simple evaluation on possible methods of removing carbon dioxide from BF gas and basic experiments on carbon dioxide capture by chemical absorption. The experimental results showed that in 100 minutes, the maximum absorbed doses of carbon dioxide reached 20 g/100 g with ionic liquid as absorbent. PMID:25078829

Zhang, Chongmin; Sun, Zhimin; Chen, Shuwen; Wang, Baohai

2013-12-01

151

Carbon Dioxide and the Greenhouse Effect: A Problem Evaluation Activity.  

ERIC Educational Resources Information Center

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

Brewer, Carol A.; Beiswenger, Jane M.

1993-01-01

152

Carbon Dioxide Addition to Microbial Fuel Cell Cathodes Maintains  

E-print Network

Carbon Dioxide Addition to Microbial Fuel Cell Cathodes Maintains Sustainable Catholyte p losses and, therefore, power losses. Here, we report that adding carbon dioxide (CO2) gas to the cathodeH imbalances in contrast to the CO2/carbonate buffered catholyte system by Torres,Lee,andRittmann[Environ. Sci

Angenent, Lars T.

153

FRONTIERS ARTICLE On the hydration and hydrolysis of carbon dioxide  

E-print Network

FRONTIERS ARTICLE On the hydration and hydrolysis of carbon dioxide Alice H. England a,b , Andrew M August 2011 a b s t r a c t The dissolution of carbon dioxide in water and the ensuing hydrolysis, and hydration strength. ? 2011 Elsevier B.V. All rights reserved. 1. Introduction The hydrolysis of carbon

Cohen, Ronald C.

154

Caffeine solubility in supercritical carbon dioxide\\/co-solvent mixtures  

Microsoft Academic Search

In order to assess the effect of co-solvents on the solubility of caffeine in supercritical carbon dioxide, experimental solubility of caffeine in supercritical ethanolcarbon dioxide and isopropanolcarbon dioxide mixed solvents was obtained using a high-pressure semi-continuous flow apparatus. Caffeine solubilities in 5% ethanol\\/95% CO2, 10% ethanol\\/90% CO2 and 5% isopropanol\\/95% CO2 mixed solvents were determined at 323.2 and 343.2K and

Uiram Kopcak; Rahoma Sadeg Mohamed

2005-01-01

155

Carbon dioxide exchange and early old-field succession  

Microsoft Academic Search

Old-field succession is a widespread process active in shaping landscapes in the eastern United States, contributing significantly to the terrestrial sink of atmospheric carbon dioxide, particularly at midlatitudes. However, few studies document ecosystem-scale carbon dioxide exchange during the early years of old-field succession, particularly during the temporal transition from cultivation to abandonment. Rates of carbon dioxide exchange were measured for

Ryan E. Emanuel; John D. Albertson; Howard E. Epstein; Christopher A. Williams

2006-01-01

156

Supercritical carbon dioxide: a solvent like no other  

PubMed Central

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

Peach, Jocelyn

2014-01-01

157

Upgrading carbon dioxide by incorporation into heterocycles.  

PubMed

Carbon dioxide is commonly regarded as the primary greenhouse gas, but from a synthetic standpoint can be utilized as an alternative and sustainable C1 synthon in organic synthesis rather than a waste. This results in the production of organic carbonates, carboxylic acids, and derivatives. Recently, CO2 has emerged as an appealing tool for heterocycle synthesis under mild conditions without using stoichiometric amounts of organometallic reducing reagents. This Minireview summarizes recent advances on methodologies for CO2 incorporation into N-, O-, and C-nucleophiles to provide various heterocycles, including cyclic carbamates, benzoxazine-2-one, 4-hydroxyquinolin-2-one, quinazoline-2,4(1?H,3?H)-diones, benzimidazolones, ?-alkylidene cyclic carbonate. PMID:25209543

Yu, Bing; He, Liang-Nian

2015-01-01

158

Sequestering carbon dioxide in industrial polymers: Building materials for the 21st century  

SciTech Connect

This study was undertaken to determine the possibility of developing beneficial uses for carbon dioxide as a key component for a large-volume building product. Such a use may provide an alternative to storing the gas in oceanic sinks or clathrates as a way to slow the rate of global warming. The authors investigated the concept that carbon dioxide might be used with other chemicals to make carbon-dioxide-based polymers which would be lightweight, strong, and economical alternatives to some types of wood and silica-based building materials. As a construction-grade material, carbon dioxide would be fixed in a solid, useful form where it would not contribute to global warming. With the probable imposition of a fuel carbon tax in industrialized countries, this alternative would allow beneficial use of the carbon dioxide and could remove it from the tax basis if legislation were structured appropriately. Hence, there would be an economic driver towards the use of carbon-dioxide-based polymers which would enhance their future applications. Information was obtained through literature searches and personal contacts on carbon dioxide polymers which showed that the concept (1) is technically feasible, (2) is economically defensible, and (3) has an existing industrial infrastructure which could logically develop it. The technology exists for production of building materials which are strong enough for use by industry and which contain up to 90% by weight of carbon dioxide, both chemically and physically bound. A significant side-benefit of using this material would be that it is self-extinguishing in case of fire. This report is the first stage in the investigation. Further work being proposed will provide details on costs, specific applications and volumes, and potential impacts of this technology.

Molton, P.M.; Nelson, D.A.

1993-06-01

159

Carbon dioxide absorbent and method of using the same  

SciTech Connect

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.

Perry, Robert James; O'Brien, Michael Joseph

2014-06-10

160

Passive colorimetric dosimeter tubes for ammonia, carbon monoxide, carbon dioxide, hydrogen sulfide, nitrogen dioxide, and sulfur dioxide  

SciTech Connect

Colorimetric, stain length, personal dosimeters operating by gas diffusion have been developed to determine worker exposure for up to an 8-h period for several inorganic airborne contaminants in the range of their threshold limit values. Length of stain, colorimetric dosimeters have been made for the detection of ammonia (NH/sub 3/), carbon monoxide (CO), carbon dioxide (CO/sub 2/), hydrogen sulfide (H/sub 2/S), nitrogen dioxide (NO/sub 2/), and sulfur dioxide (SO/sub 2/) in air. For each gas detection system, the sampler depends on the transfer of the gas by diffusion into a glass tube containing a colorimetric length of stain indicator. The stain length developed in a given period of time is compared to a calibration chart to determine, on the spot, the average gas concentration to which the dosimeter has been exposed. These dosimeters are known by the trade name Vapor Gard.

McKee, E.S.; Pritts, I.M.

1981-08-01

161

Passive colorimetric dosimeter tubes for ammonia, carbon monoxide, carbon dioxide, hydrogen sulfide, nitrogen dioxide and sulfur dioxide  

SciTech Connect

Colorimetric, stain length, personal dosimeters operating by gas diffusion have been developed to determine worker exposure for up to an eight-hour period for several inorganic airborne contaminants in the range of their Threshold Limit Values. Length of stain, colorimetric dosimeters have been made for the detection of ammonia (NH/sub 3/), carbon monoxide (CO), carbon dioxide (CO/sub 2/), hydrogen sulfide (H/sub 2/S), nitrogen dioxide (NO/sub 2/), and sulfur dioxide (SO/sub 2/) in air. For each gas detection system, the sampler depends on the transfer of the gas by diffusion into a glass tube containing a colorimetric length of stain indicator. The stain length developed in a given period of time is compared to a calibration chart to determine, on the spot, the average gas concentration to which the dosimeter has been exposed. These dosimeters are known by the trade name Vapor Gard.

McConnaughey, P.W.; McKee, E.S.; Pritts, I.M.

1985-07-01

162

Displacement of crude oil by carbon dioxide  

E-print Network

that passed through the core. Seeson and Ortloff conducted a laboratory study in which they investigated the oil recovery from displacing some high and low viscosity crudes from linear sandstone models. A 400 cp Ada crude oil was displaced from linear... Topedo sandstone and a 6 cp Loudon crude oil was displaced from linear models of Weiler sand- stone at 70 F and at about 1000 psi by water propelled carbon dioxide slugs. They found that the displacement technique was more efficient than waterflooding...

Omole, Olusegun

2012-06-07

163

Sigmoid perforation by compressed carbon dioxide.  

PubMed

Self-induced injuries of the bowel have various accidental mechanisms. This is a report of a 35-year-old patient with disruption of the recto-sigmoid junction caused by carbon dioxide (CO2) originating from a bottle of sparkling wine, which was introduced transanally for sexual stimulation. The patient underwent resection of the recto-sigmoid junction and primary anastomosis. The postoperative course was uneventful except for wound infection. The patient was discharged 12 days later. The physical backgrounds, the pathological pathways for perforation and diagnostic modalities including diagnostic pitfalls are critically discussed. PMID:15932178

Ikapischke, Matthias; Tepel, Juergen; Pai, Muhdra; Schulz, Tim

2005-03-01

164

Searching for clues to ancient carbon dioxide  

SciTech Connect

Something on Earth just won't stop fiddling with the thermostat. In the past 500 million years, the planet has shivered through ice ages lasting millions of years and sweltered through episodes of global warmth. Climatologists, eager to know what keeps jiggling the planet's temperature setting, have focused their suspicions on carbon dioxide, the same heat-trapping gas expected to drive up temperatures in coming decades. Catching this suspect in the act has been difficult, however; the atmospheres of millions of years ago are gone with the wind.

Appenzeller, T.

1993-02-12

165

Electrochemical carbon dioxide concentrator subsystem development  

NASA Technical Reports Server (NTRS)

The fabrication of a one-person Electrochemical Depolarized Carbon Dioxide Concentrator subsystem incorporating advanced electrochemical, mechanical, and control and monitor instrumentation concepts is discussed. This subsystem included an advanced liquid cooled unitized core composite cell module and integrated electromechanical components. Over 1800 hours with the subsystem with removal efficiencies between 90%. and 100%; endurance tests with a Fluid Control Assembly which integrates 11 gas handling components of the subsystem; and endurance testing of a coolant control assembly which integrates a coolant pump, diverter valve and a liquid accumulator were completed.

Heppner, D. B.; Dahlausen, M. J.; Schubert, F. H.

1983-01-01

166

A Vortex Contactor for Carbon Dioxide Separations  

SciTech Connect

Many analysts identify carbon dioxide (CO2) capture and separation as a major roadblock in efforts to cost effectively mitigate greenhouse gas emissions via sequestration. An assessment 4 conducted by the International Energy Agency (IEA) Greenhouse Gas Research and Development Programme cited separation costs from $35 to $264 per tonne of CO2 avoided for a conventional coal fired power plant utilizing existing capture technologies. Because these costs equate to a greater than 40% increase in current power generation rates, it appears obvious that a significant improvement in CO2 separation technology is required if a negative impact on the world economy is to be avoided.

Raterman, Kevin Thomas; Mc Kellar, Michael George; Turner, Terry Donald; Podgorney, Anna Kristine; Stacey, Douglas Edwin; Stokes, B.; Vranicar, J.

2001-05-01

167

The kinetics of binding carbon dioxide in magnesium carbonate  

SciTech Connect

Humans currently consume about 6 Gigatons of carbon annually as fossil fuel. In some sense, the coal industry has a unique advantage over many other anthropogenic and natural emitters of CO{sub 2} in that it owns large point sources of CO{sub 2} from which this gas could be isolated and disposed of. If the increased energy demands of a growing world population are to be satisfied from coal, the implementation of sequestration technologies will likely be unavoidable. The authors` method of sequestration involves binding carbon dioxide as magnesium carbonate, a thermodynamically stable solid, for safe and permanent disposal, with minimal environmental impact. The technology is based on extracting magnesium hydroxide from common ultramafic rock for thermal carbonation and subsequent disposition. The economics of the method appear to be promising, however, many details of the proposed process have yet to be optimized. Realization of a cost effective method requires development of optimal technologies for efficient extraction and thermal carbonation.

Butt, D.P.; Lackner, K.S.; Wendt, C.H.; Vaidya, R.; Pile, D.L.; Park, Y.; Holesinger, T.; Harradine, D.M. [Los Alamos National Lab., NM (United States); Nomura, Koji [Los Alamos National Lab., NM (United States). Materials Science and Technology Div.]|[Chichibu Onada Cement Co., Tokyo (Japan)

1998-08-01

168

Atmospheric carbon dioxide and the global carbon cycle  

SciTech Connect

This state-of-the-art volume presents discussions on the global cycle of carbon, the dynamic balance among global atmospheric CO2 sources and sinks. Separate abstracts have been prepared for the individual papers. (ACR)

Trabalka, J R [ed.

1985-12-01

169

The lifetime of excess atmospheric carbon dioxide  

SciTech Connect

Since the beginning of the industrial revolution human activity has significantly altered biogeochemical cycling on a global scale. The uncertainties of future climate change rests partly on issues of physical-climate system dynamics and their representation in general circulation models. However understanding the carbon cycle is a key to comprehending the changing terrestrial biosphere and to developing a reasonable range of future concentrations of greenhouse gases. The authors look at correction of model uncertainties in the examination of the lifetime of carbon dioxide. The two difficulties analysed are as follows: (1) most model-derived estimates of the relaxation of the concentration of CO2 reveal a function which is not always well approximated by weighted sums of exponentials; (2) the function c(t) is quite sensitive to assumptions about the terrestrial biosphere and the relaxation experiment. 51 refs., 15 figs., 7 tabs.

Moore, B. III; Braswell, B.H. (Univ. of New Hampshire, Durham, NH (United States))

1994-03-01

170

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

Code of Federal Regulations, 2010 CFR

...2010-04-01 2010-04-01 false Indwelling blood carbon dioxide partial pressure (PCO2...Diagnostic Devices 868.1150 Indwelling blood carbon dioxide partial pressure (PCO2... (a) Identification. An indwelling blood carbon dioxide partial pressure...

2010-04-01

171

46 CFR 167.45-45 - Carbon dioxide fire extinguishing system requirements.  

Code of Federal Regulations, 2014 CFR

...2014-10-01 2014-10-01 false Carbon dioxide fire extinguishing system requirements...Prevention Requirements 167.45-45 Carbon dioxide fire extinguishing system requirements. (a) When a carbon dioxide (CO2 ) smothering...

2014-10-01

172

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

Code of Federal Regulations, 2014 CFR

... 2014-10-01 2014-10-01 false Carbon dioxide and clean agent alarms. 97.37-9...Emergency Equipment, Etc. 97.37-9 Carbon dioxide and clean agent alarms. Each carbon dioxide or clean agent fire extinguishing...

2014-10-01

173

46 CFR 196.37-9 - Carbon dioxide and clean agent alarms.  

Code of Federal Regulations, 2014 CFR

...2014-10-01 2014-10-01 false Carbon dioxide and clean agent alarms. 196...Equipment, etc. 196.37-9 Carbon dioxide and clean agent alarms. Each extinguishing system using carbon dioxide or clean agent complying...

2014-10-01

174

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

Code of Federal Regulations, 2014 CFR

...transportation of hazardous liquids or carbon dioxide. 195.4 Section 195.4...transportation of hazardous liquids or carbon dioxide. No person may transport any hazardous liquid or carbon dioxide unless the hazardous liquid...

2014-10-01

175

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

Code of Federal Regulations, 2014 CFR

... 2014-10-01 2014-10-01 false Carbon dioxide and clean agent alarms. 78.47-9...Emergency Equipment, Etc. 78.47-9 Carbon dioxide and clean agent alarms. Each carbon dioxide or clean agent fire extinguishing...

2014-10-01

176

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

Code of Federal Regulations, 2012 CFR

... 2012-10-01 2012-10-01 false Carbon dioxide and clean agent alarms. 78.47-9...Emergency Equipment, Etc. 78.47-9 Carbon dioxide and clean agent alarms. Each carbon dioxide or clean agent fire extinguishing...

2012-10-01

177

46 CFR 131.815 - Carbon dioxide and clean agent alarms.  

Code of Federal Regulations, 2013 CFR

... 2013-10-01 2013-10-01 false Carbon dioxide and clean agent alarms. 131.815...Equipment and Emergency Equipment 131.815 Carbon dioxide and clean agent alarms. Each carbon dioxide or clean agent fire extinguishing...

2013-10-01

178

The Carbon Dioxide Greenhouse: Is It Effective?  

NSDL National Science Digital Library

This activity allows students to compare the thermal properties of carbon dioxide with those of air, and can be extended to compare water vapor as well. Students discover that the gas which absorbs the most heat (infrared radiation) is the most effective greenhouse gas because in the atmosphere it would absorb more infrared coming from the surface of the Earth. This activity could be used as either a demonstration or a laboratory activity depending on the availability of equipment. Either a data logger is used to record the changing temperature of air and of carbon dioxide in plastic bottles as they are heated using electric lamps, and then allowed to cool, or if a data logger is not available, then thermometers can be used instead and monitored by students. The site contains teacher notes and instructions with a list of materials and a photograph showing the setup. It also has an introduction for the students and questions for them to answer along with a glossary.

179

Chemical Reactions in Supercritical Carbon Dioxide  

NASA Astrophysics Data System (ADS)

Utilizing supercritical fluids as environmentally benign solvents for chemical synthesis is one of the new approaches in the "greening" of chemistry. Carbon dioxide is the most widely used gas for supercritical fluid studies because of its moderate critical constants, nontoxic nature, and availability in pure form. One unique property of supercritical carbon dioxide (sc-CO2) is its high solubility for fluorinated compounds. Thus sc-CO2 can be used to replace Freons that are conventionally used as solvents for synthesis of perfluoro-polymers. Another property of sc-CO2 is its miscibility with gases such as H2. Heterogeneous reactions involving these gases may become homogeneous reactions in sc-CO2. Reactions in sc-CO2 may offer several advantages including controlling phase behavior and products, increasing speed of reactions, and obtaining specific reaction channels. This paper describes the following nine types of chemical reactions reported in the literature utilizing sc-CO2 as a solvent to illustrate the unique properties of the supercritical fluid reaction systems: (i) hydrogenation and hydroformylation, (ii) synthesis of organometallic compounds, (iii) metal chelation and extraction, (iv) preparation of inorganic nanoparticles, (v) stereo-selectivity of lipase-catalyzed reactions, (vi) asymmetric catalytic hydrogenation, (vii) polymerization, (viii) Diels-Alder reaction, and (ix) free radical reactions.

Wai, Chien M.; Hunt, Fred; Ji, Min; Chen, Xiaoyuan

1998-12-01

180

Carbon dioxide utilisation of Dunaliella tertiolecta for carbon bio-mitigation in a semicontinuous photobioreactor.  

PubMed

Bio-fixation of carbon dioxide (CO2) by microalgae has been recognised as an attractive approach to offset anthropogenic emissions. Biological carbon mitigation is the process whereby autotrophic organisms, such as microalgae, convert CO2 into organic carbon and O2 through photosynthesis; this process through respiration produces biomass. In this study Dunaliella tertiolecta was cultivated in a semicontinuous culture to investigate the carbon mitigation rate of the system. The algae were produced in 1.2-L Roux bottles with a working volume of 1 L while semicontinuous production commenced on day 4 of cultivation when the carbon mitigation rate was found to be at a maximum for D. tertiolecta. The reduction in CO2 between input and output gases was monitored to predict carbon fixation rates while biomass production and microalgal carbon content are used to calculate the actual carbon mitigation potential of D. tertiolecta. A renewal rate of 45 % of flask volume was utilised to maintain the culture in exponential growth with an average daily productivity of 0.07 g L(-1) day(-1). The results showed that 0.74 g L(-1) of biomass could be achieved after 7 days of semicontinuous production while a total carbon mitigation of 0.37 g L(-1) was achieved. This represented an increase of 0.18 g L(-1) in carbon mitigation rate compared to batch production of D. tertiolecta over the same cultivation period. PMID:24162085

Farrelly, Damien J; Brennan, Liam; Everard, Colm D; McDonnell, Kevin P

2014-04-01

181

Carbon Dioxide Fluxes in European Russia  

NASA Astrophysics Data System (ADS)

Measurements of carbon balance of boreal ecosystems in the southern taiga of European Russia have been conducted using eddy covariance technique starting from 1998 to the present. The method allows to continuously collect net ecosystem exchange (NEE) fluxes of water and heat between forest and atmosphere with high time resolution. Simultaneous measurements of atmospheric meteorological parameters are carried out. The studies have been conducted in the Tver Region, Russia (Central Forest Biosphere Nature Reserve, 56N, 33E) using a 29 m high tower in low-productive wet spruce forest (P. Sphagnum forest, WSF), a 44 m high tower in high- productive complex spruce forest (CSF) and under the surface of ombrotrophic bog. Eddy flux measurements during limited time intervals are supplemented by measurements of soil, leaves and trunks respiration. Observations of decomposition speed of organic material and the rating NPP are conducted as well. In general, the measurements period has captured a wide range of changes of climatic conditions. Years with extreme dry and damp vegetative seasons and years with close to average climatic conditions for this region fall into the period of observations. The results of our measurements show that unmanaged uneven-aged spruce forests can be both source and sink of carbon to the atmosphere depending on the type of forest and weather conditions. Soil respiration as a result of decomposition of the abundant dead surface- and underground biomass determines the sign and absolute mean of the carbon balance. The overall annual balance of carbon of the studied forest ecosystems differs from zero. The cumulative total of the NEE fluxes for the period of April to October depends first of all on spring temperature and precipitation with temperature being within the range of 5-10C and on the duration of this period. For the period of active vegetation, when air temperature is higher than 10C - the NEE flux depends on humidity. We found significant seasonal and interannual variability of carbon dioxide fluxes for the ombrotrophic bog. The sign and the mean of carbon dioxide fluxes between the surface of the bog and the atmosphere depend on humidity conditions during the green season. When the water balance is negative the ombotrophic bog becomes a source of carbon for the atmosphere.

Kurbatova, J.; Varlagin, A.; Vygodskaya, N.

2007-12-01

182

Hydrodynamic Controls on Carbon Dioxide Efflux from Inland Waters  

NASA Astrophysics Data System (ADS)

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 ?mol 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 ?mol 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.

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

2013-12-01

183

Mechanistical studies on the formation of carbon dioxide in extraterrestrial carbon monoxide ice analog samples  

E-print Network

Mechanistical studies on the formation of carbon dioxide in extraterrestrial carbon monoxide ice with extraterrestrial, carbon monoxide bearing ices. The chemical modifications were monitored on line and in situ via of carbon monoxide and on the formation of carbon dioxide in extraterrestrial ice analog samples. 1

Kaiser, Ralf I.

184

Carbon dioxide emission during forest fires ignited by lightning  

E-print Network

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

Pelc, Magdalena

2009-01-01

185

Carbon Dioxide, Global Warming, and Michael Crichton's "State of Fear"  

E-print Network

Carbon Dioxide, Global Warming, and Michael Crichton's "State of Fear" Bert W. Rust Mathematical- tioned the connection between global warming and increasing atmospheric carbon dioxide by pointing out of these plots to global warming have spilled over to the real world, inviting both praise [4, 17] and scorn [15

Rust, Bert W.

186

Carbon Dioxide and Global Warming: A Failed Experiment  

ERIC Educational Resources Information Center

Global warming is a current environmental issue that has been linked to an increase in anthropogenic carbon dioxide in the atmosphere. To raise awareness of the problem, various simple experiments have been proposed to demonstrate the effect of carbon dioxide on the planet's temperature. This article describes a similar experiment, which

Ribeiro, Carla

2014-01-01

187

Performance of air filters cleaned by supercritical carbon dioxide  

Microsoft Academic Search

A new technique based on the use of supercritical carbon dioxide (CO2) for cleaning HEPA filters was developed. Glass fiber filters and polytetrafluoroethylene (PTFE) membranes loaded with dioctylphthalate (DOP) droplets were cleaned with supercritical carbon dioxide under various conditions. The cleaning performance was evaluated by the weight recovery of the filter media and the recoveries of their collection efficiencies and

Takao Ito; Yoshio Otani; Hiroshi Inomata

2004-01-01

188

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

Code of Federal Regulations, 2013 CFR

(a) Carbon dioxide, solid (dry ice), when offered for transportation or transported by aircraft or water, must be packed in packagings designed and constructed to permit the release of carbon dioxide gas to prevent a buildup of pressure that could rupture the...

2013-10-01

189

21 CFR 868.5300 - Carbon dioxide absorbent.  

Code of Federal Regulations, 2013 CFR

A carbon dioxide absorbent is a device intended for medical purposes that consists of an absorbent material (e.g., soda lime) that is intended to remove carbon dioxide from the gases in the breathing circuit. (b) Classification. Class I (general...

2013-04-01

190

21 CFR 868.5310 - Carbon dioxide absorber.  

Code of Federal Regulations, 2013 CFR

A carbon dioxide absorber is a device that is intended for medical purposes and that is used in a breathing circuit as a container for carbon dioxide absorbent. It may include a canister and water drain. (b) Classification. Class I (general...

2013-04-01

191

Climate Science in a Nutshell: Where Carbon Dioxide Come From?  

NSDL National Science Digital Library

This short video discusses where carbon dioxide, the gas that is mainly responsible for warming up our planet and changing the climate, comes from. It discusses how the rise in atmospheric carbon dioxide comes directly from the burning of fossil fuels and indirectly from the human need for energy.

Planet Nutshell

192

Promising flame retardant textile in supercritical carbon dioxide  

Technology Transfer Automated Retrieval System (TEKTRAN)

Since carbon dioxide is non-toxic, non-flammable and cost-effective, supercritical carbon dioxide (scCO2) is widely used in textile dyeing applications. Due to its environmentally benign character, scCO2 is considered in green chemistry as a substitute for organic solvents in chemical reactions. O...

193

Blended polymer materials extractable with supercritical carbon dioxide  

Microsoft Academic Search

Supercritical carbon dioxide is drawing more and more attention because of its unique solvent properties along with being environmentally friendly. Historically most of the commercial interests of supercritical carbon dioxide extraction are in the food industry, pharmaceutical industry, environmental preservation and polymer processing. Recently attention has shifted from the extraction of relatively simple molecules to more complex systems with a

Mei Cai

1999-01-01

194

Urban Evapotranspiration and Carbon Dioxide Flux in Miami - Dade, Florida  

Microsoft Academic Search

Atmospheric Carbon Dioxide (CO2) concentrations are leading indicators of secular climate change. With increasing awareness of the consequences of climate change, methods for monitoring this change are becoming more important daily. Of particular interest is the carbon dioxide exchange between natural and urban landscapes and the correlation of atmospheric CO2 concentrations. Monitoring Evapotranspiration (ET) is important for assessments of water

T. Bernier; W. Hopper

2010-01-01

195

Irreversible climate change due to carbon dioxide emissions  

Microsoft Academic Search

The severity of damaging human-induced climate change depends not only on the magnitude of the change but also on the potential for irreversibility. This paper shows that the climate change that takes place due to increases in carbon dioxide concentration is largely irreversible for 1,000 years after emissions stop. Following cessation of emissions, removal of atmospheric carbon dioxide decreases radiative

Susan Solomon; Gian-Kasper Plattner; Reto Knutti; Pierre Friedlingstein

2009-01-01

196

Carbon dioxide sequestration by ex-situ mineral carbonation  

SciTech Connect

The process developed for carbon dioxide sequestration utilizes a slurry of water mixed with olivine- forsterite end member (Mg{sub 2}SiO{sub 4}), which is reacted with supercritical CO{sub 2} to produce magnesite (MgCO{sub 3}). Carbon dioxide is dissolved in water to form carbonic acid, which likely dissociates to H{sup +} and HCO{sub 3}{sup -}. The H{sup +} hydrolyzes the silicate mineral, freeing the cation (Mg{sup 2+}), which reacts with the HCO{sub 3}{sup -} to form the solid carbonate. Results of the baseline tests, conducted on ground products of the natural mineral, have demonstrated that the kinetics of the reaction are slow at ambient temperature (22 degrees C) and subcritical CO{sub 2} pressures (below 7.4 MPa). However, at elevated temperature and pressure, coupled with continuous stirring of the slurry and gas dispersion within the water column, significant conversion to the carbonate occurs. Extent of reaction is roughly 90% within 24 h, at 185 degrees C and partial pressure of CO{sub 2} (P{sub CO{sub 2}}) of 11.6 MPa. Current studies suggest that reaction kinetics can be improved by pretreatment of the mineral, catalysis of the reaction, and/or solution modification. Subsequent tests are intended to examine these options, as well as other mineral groups.

O'Connor, W.K.; Dahlin, D.C.; Turner, P.C.; and Walters, R.P.

2000-01-01

197

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

USGS Publications Warehouse

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 ?eq/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.

Colt, John; Watten, Barnaby; Pfeiffer, Tim

2012-01-01

198

ORNL/CDIAC-143 CARBON DIOXIDE, HYDROGRAPHIC, AND CHEMICAL DATA OBTAINED DURING THE  

E-print Network

Kozyr Carbon Dioxide Information Analysis Center Oak Ridge National Laboratory Oak Ridge, Tennessee, U Prepared by the Carbon Dioxide Information Analysis Center OAK RIDGE NATIONAL LABORATORY Oak Ridge

199

Carbon dioxide sorption capacities of gasified coal seams and their surrounding rocks  

NASA Astrophysics Data System (ADS)

Underground coal gasification (UCG) is considered a viable approach for the development of deep and structurally complex coal deposits that are not economically extractable by conventional mining techniques. The combination of UCG and the subsequent combustion of the resulting synthesis gas in a combined cycle plant with the storage of carbon dioxide formed during this process could provide a relevant contribution to the so called clean coal technologies. Carbon dioxide captured from the flue gas of the combined cycle plant would be injected into already gasified coal seams using the existing UCG borehole infrastructure. Within the present study different coal seams and their surrounding rocks were sampled in all German hard coal mining districts. The coal samples were treated in a laboratory gasification device to produce combustion residues comparable to those formed in the UCG process. High-pressure carbon dioxide sorption experiments were then conducted on the original coal samples, their gasified residues and the surrounding rocks. The results indicate a significant increase of porosity and carbon dioxide sorption capacity of the residual coal after gasification. Furthermore, notable carbon dioxide sorption capacities were observed for the surrounding rocks. The assessment of the carbon dioxide storage potential in gasified coal seams has to take explicitly into account the newly generated pore space, the increased sorption capacity of the gasified coals and the sorption capacity of the surrounding rocks. Furthermore, the reduction of subsurface void volumes due to mechanical compaction after gasification as well as the resulting enhanced accessibility of adjacent seams have to be equally considered.

Kempka, T.; Aeckersberg, R.; Li, D.; Kunz, E.; Krooss, B.; Golz, N.; Schlter, R.; Fernndez-Steeger, T.

2009-04-01

200

Global carbon dioxide emissions from inland waters.  

PubMed

Carbon dioxide (CO2) transfer from inland waters to the atmosphere, known as CO2 evasion, is a component of the global carbon cycle. Global estimates of CO2 evasion have been hampered, however, by the lack of a framework for estimating the inland water surface area and gas transfer velocity and by the absence of a global CO2 database. Here we report regional variations in global inland water surface area, dissolved CO2 and gas transfer velocity. We obtain global CO2 evasion rates of 1.8(+0.25)(-0.25)? petagrams of carbon (Pg?C) per year from streams and rivers and 0.32(+0.52)(-0.26)? Pg?C?yr(-1) from lakes and reservoirs, where the upper and lower limits are respectively the 5th and 95th confidence interval percentiles. The resulting global evasion rate of 2.1?Pg?C?yr(-1) is higher than previous estimates owing to a larger stream and river evasion rate. Our analysis predicts global hotspots in stream and river evasion, with about 70 per cent of the flux occurring over just 20 per cent of the land surface. The source of inland water CO2 is still not known with certainty and new studies are needed to research the mechanisms controlling CO2 evasion globally. PMID:24256802

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

2013-11-21

201

Demographic change and carbon dioxide emissions.  

PubMed

Relations between demographic change and emissions of the major greenhouse gas carbon dioxide (CO(2)) have been studied from different perspectives, but most projections of future emissions only partly take demographic influences into account. We review two types of evidence for how CO(2) emissions from the use of fossil fuels are affected by demographic factors such as population growth or decline, ageing, urbanisation, and changes in household size. First, empirical analyses of historical trends tend to show that CO(2) emissions from energy use respond almost proportionately to changes in population size and that ageing and urbanisation have less than proportional but statistically significant effects. Second, scenario analyses show that alternative population growth paths could have substantial effects on global emissions of CO(2) several decades from now, and that ageing and urbanisation can have important effects in particular world regions. These results imply that policies that slow population growth would probably also have climate-related benefits. PMID:22784534

O'Neill, Brian C; Liddle, Brant; Jiang, Leiwen; Smith, Kirk R; Pachauri, Shonali; Dalton, Michael; Fuchs, Regina

2012-07-14

202

Cooling Heat Transfer of Supercritical Carbon Dioxide  

NASA Astrophysics Data System (ADS)

The characteristics of carbon dioxide cooled under supercritical condition were investigated theoretically and experimentally. Based on the results of numerical calculation and experimental measurements described in the 1st report, a new correlation was proposed to predict the heat transfer coefficient, and the Filonenko's equation was found adequate to predict the pressure drop inside as mall seized tube. Those correlations were compared with measurement results and the deviations were found lower than 20%. Furthermore, a compressor cycle was assembled to investigate the effect of lubricant oil on heat transfer and pressure drop. The oil content in CO2 was set to be about 0.5% during the measurements. This amount of lubricant oil was found affected the heat transfer coefficient significantly, with largest degradation of heat transfer coefficient at the pseudocritical point to nearly 50%. The effect of lubricant oil at small concentration on the pressure drop was found negligible.

Dang, Chaobin; Hihara, Eiji

203

Layered solid sorbents for carbon dioxide capture  

DOEpatents

A solid sorbent for the capture and the transport of carbon dioxide gas is provided having at least one first layer of a positively charged material that is polyethylenimine or poly(allylamine hydrochloride), that captures at least a portion of the gas, and at least one second layer of a negatively charged material that is polystyrenesulfonate or poly(acryclic acid), that transports the gas, wherein the second layer of material is in juxtaposition to, attached to, or crosslinked with the first layer for forming at least one bilayer, and a solid substrate support having a porous surface, wherein one or more of the bilayers is/are deposited on the surface of and/or within the solid substrate. A method of preparing and using the solid sorbent is provided.

Li, Bingyun; Jiang, Bingbing; Gray, McMahan L; Fauth, Daniel J; Pennline, Henry W; Richards, George A

2014-11-18

204

Pulsed-discharge carbon dioxide lasers  

NASA Technical Reports Server (NTRS)

The purpose is to attempt a general introduction to pulsed carbon dioxide lasers of the kind used or proposed for laser radar applications. Laser physics is an excellent example of a cross-disciplinary topic, and the molecular spectroscopy, energy transfer, and plasma kinetics of the devices are explored. The concept of stimulated emission and population inversions is introduced, leading on to the molecular spectroscopy of the CO2 molecule. This is followed by a consideration of electron-impact pumping, and the pertinent energy transfer and relaxation processes which go on. Since the devices are plasma pumped, it is necessary to introduce a complex subject, but this is restricted to appropriate physics of glow discharges. Examples of representative devices are shown. The implications of the foregoing to plasma chemistry and gas life are discussed.

Willetts, David V.

1990-01-01

205

New Trends In Carbon Dioxide Laser Microsurgery  

NASA Astrophysics Data System (ADS)

The carbon dioxide laser has been used for cutting and cauterizing tissue in a variety of surgical procedures by means of a dry-field air/tissue interface approach. Recently, a new wet-field CO2 laser technique has been developed and is being used successfully in humans to seal intraocular fibrovascular fronds and retinal tears at the time of vitrectomy, to close rubeotic vessels in the iris, and to excise fibrovascular fronds and epiretinal membranes in cases of severe diabetic retinopathy. Specialized wet-field CO2 photosurgical probes for use in gynecologic microsurgery have been developed and are being studied experimentally. Other potential applications include otolaryngologic micro-surgery, neurosurgery, and gastrointestinal and urologic wet-field surgery.

Smith, M. R.; Miller, James B.

1981-05-01

206

CARBON DIOXIDE CAPTURE FROM FLUE GAS USING DRY REGENERABLE SORBENTS  

SciTech Connect

This report describes research conducted between October 1, 2004 and December 31, 2004 on the use of dry regenerable sorbents for removal of carbon dioxide from flue gas. Two supported sorbents were tested in a bench scale fluidized bed reactor system. The sorbents were prepared by impregnation of sodium carbonate on to an inert support at a commercial catalyst manufacturing facility. One sorbent, tested through five cycles of carbon dioxide sorption in an atmosphere of 3% water vapor and 0.8 to 3% carbon dioxide showed consistent reactivity with sodium carbonate utilization of 7 to 14%. A second, similarly prepared material, showed comparable reactivity in one cycle of testing. Batches of 5 other materials were prepared in laboratory scale quantities (primarily by spray drying). These materials generally have significantly greater surface areas than calcined sodium bicarbonate. Small scale testing showed no significant adsorption of mercury on representative carbon dioxide sorbent materials under expected flue gas conditions.

David A. Green; Brian S. Turk; Jeffrey W. Portzer; Thomas Nelson; Raghubir P. Gupta

2005-01-01

207

Does carbon dioxide pool or stream in the subsurface?  

E-print Network

Pools of carbon dioxide are found in natural geological accumulations and in engineered storage in saline aquifers. It has been thought that once this CO2 dissolves in the formation water, making it denser, convection streams would transport it efficiently to depth, but this may not be so. Here, we assess the impact of natural chemical reactions between the dissolved CO2 and the rock formation on the convection streams in the subsurface. We show that, while in carbonate rocks the streaming of dissolved carbon dioxide persists, the chemical interactions in silicate-rich rocks may curb this transport drastically and even inhibit it altogether. New laboratory experiments confirm the curtailing of convection by reaction. Wide and narrow streams of dense carbon-rich water are shut-off gradually as reaction strength increases until all transport of the pooled carbon dioxide occurs by slow molecular diffusion. These results show that the complex fluid dynamic and kinetic interactions between pooled carbon dioxide an...

Cardoso, Silvana S S

2014-01-01

208

Coiled tubing drilling with supercritical carbon dioxide  

DOEpatents

A method for increasing the efficiency of drilling operations by using a drilling fluid material that exists as supercritical fluid or a dense gas at temperature and pressure conditions existing at a drill site. The material can be used to reduce mechanical drilling forces, to remove cuttings, or to jet erode a substrate. In one embodiment, carbon dioxide (CO.sub.2) is used as the material for drilling within wells in the earth, where the normal temperature and pressure conditions cause CO.sub.2 to exist as a supercritical fluid. Supercritical carbon dioxide (SC--CO.sub.2) is preferably used with coiled tube (CT) drilling equipment. The very low viscosity SC--CO.sub.2 provides efficient cooling of the drill head, and efficient cuttings removal. Further, the diffusivity of SC--CO.sub.2 within the pores of petroleum formations is significantly higher than that of water, making jet erosion using SC--CO.sub.2 much more effective than water jet erosion. SC--CO.sub.2 jets can be used to assist mechanical drilling, for erosion drilling, or for scale removal. A choke manifold at the well head or mud cap drilling equipment can be used to control the pressure within the borehole, to ensure that the temperature and pressure conditions necessary for CO.sub.2 to exist as either a supercritical fluid or a dense gas occur at the drill site. Spent CO.sub.2 can be vented to the atmosphere, collected for reuse, or directed into the formation to aid in the recovery of petroleum.

Kolle , Jack J. (Seattle, WA)

2002-01-01

209

Carbon dioxide exchange and growth of a pine plantation  

SciTech Connect

The exchange of materials between the atmosphere and terrestrial ecosystem is important to an understanding of the cycling of essential elements, the deposition of mateials from the atmosphere and the entrance of pollutants into the forest ecosystems. This paper reports the results of measurements of carbon dioxide exchange in a vigorously growing pine plantation. Measurement data were incorporated into a model used to estimate annual carbon dioxide exchange and measured annual biomass accumulation in the same plantation were used to determine a carbon dioxide to biomass conversion efficiency. Carbon dioxide exchange was 10.5 metric tons per hectare and biomass accumulation was 4.5 metric tons per hectare. The conversion efficiency of cabon dioxide to biomass is about 25% less than the theoretical chemical conversion efficiency. 27 refs., 8 figs.

Murphy, Jr, C E

1981-01-01

210

Estimated Carbon Dioxide Emissions in 2008: United States  

SciTech Connect

Flow charts depicting carbon dioxide emissions in the United States have been constructed from publicly available data and estimates of state-level energy use patterns. Approximately 5,800 million metric tons of carbon dioxide were emitted throughout the United States for use in power production, residential, commercial, industrial, and transportation applications in 2008. Carbon dioxide is emitted from the use of three major energy resources: natural gas, coal, and petroleum. The flow patterns are represented in a compact 'visual atlas' of 52 state-level (all 50 states, the District of Columbia, and one national) carbon dioxide flow charts representing a comprehensive systems view of national CO{sub 2} emissions. Lawrence Livermore National Lab (LLNL) has published flow charts (also referred to as 'Sankey Diagrams') of important national commodities since the early 1970s. The most widely recognized of these charts is the U.S. energy flow chart (http://flowcharts.llnl.gov). LLNL has also published charts depicting carbon (or carbon dioxide potential) flow and water flow at the national level as well as energy, carbon, and water flows at the international, state, municipal, and organizational (i.e. United States Air Force) level. Flow charts are valuable as single-page references that contain quantitative data about resource, commodity, and byproduct flows in a graphical form that also convey structural information about the system that manages those flows. Data on carbon dioxide emissions from the energy sector are reported on a national level. Because carbon dioxide emissions are not reported for individual states, the carbon dioxide emissions are estimated using published energy use information. Data on energy use is compiled by the U.S. Department of Energy's Energy Information Administration (U.S. EIA) in the State Energy Data System (SEDS). SEDS is updated annually and reports data from 2 years prior to the year of the update. SEDS contains data on primary resource consumption, electricity generation, and energy consumption within each economic sector. Flow charts of state-level energy usage and explanations of the calculations and assumptions utilized can be found at: http://flowcharts.llnl.gov. This information is translated into carbon dioxide emissions using ratios of carbon dioxide emissions to energy use calculated from national carbon dioxide emissions and national energy use quantities for each particular sector. These statistics are reported annually in the U.S. EIA's Annual Energy Review. Data for 2008 (US. EIA, 2010) was updated in August of 2010. This is the first presentation of a comprehensive state-level package of flow charts depicting carbon dioxide emissions for the United States.

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

2011-04-01

211

Herbivore responses to plants grown in enriched carbon dioxide atmospheres  

SciTech Connect

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 and 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.

Lincoln, D.E.

1990-05-01

212

Effect of carbon dioxide inhalation on pulmonary hypertension induced by increased blood flow and hypoxia  

Microsoft Academic Search

There is now increasing evidence from the experimental and clinical setting that therapeutic hypercapnia from intentionally inspired carbon dioxide (CO2) or lower tidal volume might be a beneficial adjunct to the strategies of mechanical ventilation in critical illness. Although previous reports indicate that CO2 exerts a beneficial effect in the lungs, the pulmonary vascular response to hypercapnia under various conditions

I-Chun Chuang; Rei-Cheng Yang; Shah-Hwa Chou; Li-Ru Huang; Tsen-Ni Tsai; Huei-Ping Dong; Ming-Shyan Huang

2011-01-01

213

CARBON DIOXIDE CAPTURE FROM FLUE GAS USING DRY REGENERABLE SORBENTS  

SciTech Connect

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

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

2005-07-01

214

CARBON DIOXIDE CAPTURE FROM FLUE GAS USING DRY REGENERABLE SORBENTS  

SciTech Connect

This report describes research conducted between January 1, 2005 and March 31, 2005 on the use of dry regenerable sorbents for removal of carbon dioxide from flue gas. Engineered sorbents composed of sodium carbonate on a ceramic support were tested in a laboratory fluidized bed reactor system and found to be capable of essentially complete removal of carbon dioxide at 60 C in a short residence time. Upon breakthrough the sorbents can be thermally regenerated to recover essentially all of the absorbed carbon dioxide. An optimized supported sorbent tested in a pilot-scale entrained bed absorber retained its reactivity in multicycle tests and experienced no attrition. Removal of >90% of carbon dioxide in simulated flue gas was achieved in an entrained bed reactor.

David A. Green; Thomas Nelson; Brian S. Turk; Jeffrey W. Portzer; Raghubir P. Gupta

2005-04-01

215

Forest management techniques for carbon dioxide storage  

SciTech Connect

In the global ecosystem concerning carbon dioxide content in the atmosphere, the forest ecosystem plays an important role. In effect, the ratio of forest biomass to total terrestrial biomass is about 90%, and the ratio of carbon stored in the forest biomass to that in the atmosphere is two thirds. When soils and detritus of forests are added, there is more C stored in forests than in the atmosphere, about 1.3 times or more. Thus, forests can be regarded as the great holder of C on earth. If the area of forest land on the earth is constantly maintained and forests are in the climax stage, the uptake of C and the release of C by and from the forests will balance. In this case, forests are neither sinks nor sources of CO{sub 2} although they store a large amount of C. However, when forests are deforested, they become a source of C; through human activities, forests have become a source of C. According to a report by the IPCC, 1.6{+-}1.2 PgC is annually added to the atmosphere by deforestation. According to the FAO (1992), the area of land deforested annually in the tropics from 1981 to 1990 was 16.9 x 10{sup 6} ha. This value is nearly half the area of Japanese land. The most important thing for the CO{sub 2} environment concerning forests is therefore how to reduce deforestation and to successfully implement a forestation or reforestation.

Fujimori, Takao [Forestry and Forest Products Research Inst., Tsukuba, Ibaraki (Japan)

1993-12-31

216

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

DOEpatents

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.

Aines, Roger D.; Bourcier, William L.

2014-08-19

217

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

DOEpatents

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.

Aines, Roger D. (Livermore, CA); Bourcier, William L. (Livermore, CA)

2010-11-09

218

Carbon dioxide euthanasia in rats: oxygen supplementation minimizes signs of agitation and asphyxia  

Microsoft Academic Search

Summary This paper records the effects of carbon dioxide when used for euthanasia, on behaviour, electrical brain activity and heart rate in rats. Four different methods were used. Animals were placed in a box (a) that was completely filled with carbon dioxide; (b) into which carbon dioxide was streamed at a high flow rate; leiinto which carbon dioxide was streamed

A. M. L. Coenen; W. H. I. M. Drinkenburgl; R. Hoenderken; E. L. J. M. van Luijtelaar

1995-01-01

219

Separation of Carbon Monoxide and Carbon Dioxide for Mars ISRU  

NASA Technical Reports Server (NTRS)

The atmosphere of Mars has many resources that can be processed to produce things such as oxygen, fuel, buffer gas, and water for support of human exploration missions. Successful manipulation of these resources is crucial for safe, cost-effective, and self-sufficient long-term human exploration of Mars. In our research, we are developing enabling technologies that require fundamental knowledge of adsorptive gas storage and separation processes. In particular, we are designing and constructing an innovative, low mass, low power separation device to recover carbon dioxide and carbon monoxide for Mars ISRU (in-situ resource utilization). The technology has broad implications for gas storage and separations for gas-solid systems that are ideally suited for reduced gravitational environments. This paper describes our separation process design and experimental procedures and reports results for the separation of CO2 and CO by a four-step adsorption cycle.

Walton, Krista S.; LeVan, M. Douglas

2004-01-01

220

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

DOEpatents

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.

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

2013-01-29

221

System-Level Analysis Modeling of Impacts of Operation Schemes of Geologic Carbon Dioxide Storage on Deep Groundwater and Carbon Dioxide Leakage Risk  

NASA Astrophysics Data System (ADS)

The objectives of this study are to predict quantitatively groundwater and carbon dioxide flow in deep saline sandstone aquifers under various carbon dioxide injection schemes (injection rate, injection period) and to analyze integratively impacts of such carbon dioxide injection schemes on deep groundwater (brine) and carbon dioxide leakage risk through abandoned wells or faults. In order to achieve the first objective, a series of process-level prediction modeling of groundwater and carbon dioxide flow in a deep saline sandstone aquifer under several carbon dioxide injection schemes was performed using a multiphase thermo-hydrological numerical model TOUGH2 (Pruess et al., 1999). The prediction modeling results show that the extent of carbon dioxide plume is significantly affected by such carbon dioxide injection schemes. In order to achieve the second objective, a series of system-level analysis modeling of deep groundwater and carbon dioxide leakage risk through an abandoned well or a fault under several carbon dioxide injection schemes was then performed using a brine and carbon dioxide leakage risk analysis model CO2-LEAK (Kim, 2012). The analysis modeling results show that the rates and amounts of deep groundwater and carbon dioxide leakage through an abandoned well or a fault increase as the carbon dioxide injection rate increases. However, the rates and amounts of deep groundwater and carbon dioxide leakage through an abandoned well or a fault decrease as the carbon dioxide injection period increases. These system-level analysis modeling results for deep groundwater and carbon dioxide leakage risk can be utilized as baseline data for establishing guidelines to mitigate anticipated environmental adverse effects on shallower groundwater systems (aquifers) when deep groundwater and carbon dioxide leakage occur. This work was supported by the Geo-Advanced Innovative Action (GAIA) Program funded by the Korea Environmental Industry and Technology Institute (KEITI), Ministry of Environment, Republic of Korea.

Park, S.; Lee, S.; Park, J.; Kim, J.; Kihm, J.

2013-12-01

222

Synthesis of Amides and Lactams in Supercritical Carbon Dioxide  

E-print Network

Supercritical carbon dioxide can be employed as an environmentally friendly alternative to conventional organic solvents for the synthesis of a variety of carboxylic amides. The addition of amines to ketenes generated in ...

Mak, Xiao Yin

223

World energy consumption and carbon dioxide emissions : 1950-2050  

E-print Network

Emissions of carbon dioxide form combustion of fossil fuels, which may contribute to long-term climate change, are projected through 2050 using reduced form models estimated with national-level panel data for the period ...

Schmalensee, Richard

1995-01-01

224

The oxygen and carbon dioxide balance in the earth's atmosphere  

NASA Technical Reports Server (NTRS)

The oxygen-carbon dioxide cycle is described in detail, and steps which are sensitive to perturbation or instability are identified. About half of the carbon dioxide consumption each year in photosynthesis occurs in the oceans. Phytoplankton, which are the primary producers, have been shown to assimilate insecticides and herbicides. The impact of such materials on phytoplankton photosynthesis, both direct and as the indirect result of detrimental effects higher up in the food chain, cannot be assessed. Net oxygen production is very small in comparison with the total production and occurs almost exclusively in a few ocean areas with anoxic bottom conditions and in peat-forming marshes which are sensitive to anthropogenic disturbances. The carbon dioxide content of the atmosphere is increasing at a relatively rapid rate as the result of fossil fuel combustion. Increases in photosynthesis as the result of the hothouse effect may in turn reduce the carbon dioxide content of the atmosphere, leading to global cooling.

Johnson, F. S.

1975-01-01

225

Atmospheric concentrations of carbon dioxide, methane and nitrous oxide  

NSDL National Science Digital Library

This is a figure from the 2007 IPCC Assessment Report 4 on atmospheric concentrations of carbon dioxide, methane and nitrous oxide over the last 10,000 years (large panels) and since 1750 (inset panels).

IPCC (Intergovernmental Panel of Climate Change)

226

Partitioning Carbon Dioxide and Water Vapor Fluxes Using Correlation Analysis  

Technology Transfer Automated Retrieval System (TEKTRAN)

Partitioning of eddy covariance flux measurements is routinely done to quantify the contributions of separate processes to the overall fluxes. Measurements of carbon dioxide fluxes represent the difference between gross ecosystem photosynthesis and total respiration, while measurements of water vapo...

227

Control strategies for supercritical carbon dioxide power conversion systems  

E-print Network

The supercritical carbon dioxide (S-C02) recompression cycle is a promising advanced power conversion cycle which couples well to numerous advanced nuclear reactor designs. This thesis investigates the dynamic simulation ...

Carstens, Nathan, 1978-

2007-01-01

228

Separation of carbon dioxide from flue emissions using Endex principles  

E-print Network

In an Endex reactor endothermic and exothermic reactions are directly thermally coupled and kinetically matched to achieve intrinsic thermal stability, efficient conversion, autothermal operation, and minimal heat losses. Applied to the problem of in-line carbon dioxide separation from flue gas, Endex principles hold out the promise of effecting a carbon dioxide capture technology of unprecedented economic viability. In this work we describe an Endex Calcium Looping reactor, in which heat released by chemisorption of carbon dioxide onto calcium oxide is used directly to drive the reverse reaction, yielding a pure stream of carbon dioxide for compression and geosequestration. In this initial study we model the proposed reactor as a continuous-flow dynamical system in the well-stirred limit, compute the steady states and analyse their stability properties over the operating parameter space, flag potential design and operational challenges, and suggest an optimum regime for effective operation.

Ball, R

2009-01-01

229

Effect of Electronarcosis on Oxygen Consumption and Carbon Dioxide Output  

Microsoft Academic Search

IN assessing changes of vital function during electronarcosis, we measured oxygen consumption and carbon dioxide output in an experiment in rabbits. The measured values were considered an important index for the evaluation of metabolic changes during electronarcosis.

Jaroslav Strmiska; Antonn Vacek

1960-01-01

230

9 CFR 313.5 - Chemical; carbon dioxide.  

Code of Federal Regulations, 2014 CFR

...by the elimination of sharp projections or exposed wheels or gears. There shall be no unnecessary holes, spaces or openings...gas supplied to anesthesia chambers may be from controlled reduction of solid carbon dioxide or from a controlled liquid...

2014-01-01

231

DEVELOPMENT AND INTEGRATION OF NEW PROCESSES CONSUMING CARBON DIOXIDE IN  

E-print Network

............................................................... 3 B. Greenhouse Effect and Climate Change............................................. 4 1. Estimation of Greenhouse Gas Emissions....................................... 6 2. Greenhouse Gas Emissions........................................................ 8 C. Carbon Dioxide ­ A Greenhouse Gas................................................ 9 1. Sources

Pike, Ralph W.

232

Electrochemically-mediated amine regeneration for carbon dioxide separations  

E-print Network

This thesis describes a new strategy for carbon dioxide (CO?) separations based on amine sorbents, which are electrochemically-mediated to facilitate the desorption and regeneration steps of the separation cycle. The ...

Stern, Michael C. (Michael Craig)

2014-01-01

233

Submarine seep of carbon dioxide in Norton Sound, Alaska  

USGS Publications Warehouse

Earlier workers have described a submarine gas seep in Norton Sound having an unusual mixture of petroleum-like, low-molecular-weight hydrocarbons. Actually, only about 0.04 percent of the seeping gas is hydrocarbons and 98 percent is carbon dioxide. The isotopic compositions of carbon dioxide (??13CPDB = -2.7 per mil) and methane (??13CPDB = -36 per mil, where PDB is the Peedee belemnite standard) indicate that geothermal processes are active here. Copyright ?? 1979 AAAS.

Kvenvolden, K.A.; Weliky, K.; Nelson, H.; Des Marais, D.J.

1979-01-01

234

Tethered catalysts for the hydration of carbon dioxide  

SciTech Connect

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.

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

235

Extraction of lemongrass essential oil with dense carbon dioxide  

Microsoft Academic Search

Lemongrass (Cymbopogon citratus) essential oil was extracted with dense carbon dioxide at 2350C and 85120 bar. The composition of samples collected during the first and the last hours of the extraction experiments was analyzed by gas chromatographymass spectrometry, and coextraction of cuticular waxes was observed. Liquid carbon dioxide extracts had a larger quantity of coextracted waxes than the supercritical extracts.

Luiz Henrique Castelan Carlson; Ricardo Antonio Francisco Machado; Cinthia Bittencourt Spricigo; Lia Krcken Pereira; Ariovaldo Bolzan

2001-01-01

236

Carbon dioxide in the ocean surface: The homogeneous buffer factor  

USGS Publications Warehouse

The amount of carbon dioxide that can be dissolved in surface seawater depends at least partially on the homogeneous buffer factor, which is a mathematical function of the chemical equilibrium conditions among the various dissolved inorganic species. Because these equilibria are well known, the homogeneous buffer factor is well known. Natural spatial variations depend very systematically on sea surface temperatures, and do not contribute significantly to uncertainties in the present or future carbon dioxide budget. Copyright ?? 1979 AAAS.

Sundquist, E.T.; Plummer, L.N.; Wigley, T.M.L.

1979-01-01

237

Methanolysis of seed oils in flowing supercritical carbon dioxide  

Microsoft Academic Search

The direct methanolysis of triglycerides in flowing supercritical carbon dioxide by an immobilized lipase is described. The\\u000a reaction system consists of two syringe pumps for substrate addition and another two syringe pumps for delivering CO2 at 24.1 MPa. Corn oil is pumped into the carbon dioxide stream at a rate of 4 ?L\\/min, and methanol is pumped at 5 ?L\\/min

Michael A. Jackson; Jerry W. King

1996-01-01

238

ABSORPTION OF CARBON DIOXIDE INTO AQUEOUS DIETHANOLAMINE SOLUTIONS  

Microsoft Academic Search

The rates of absorption of pure carbon dioxide into aqueous diethanolamine solutions were measured at 25C in a liquid-jet column and a wetted-wall column. Experimental results were analyzed with the chemical absorption theory based on the penetration model. Physical solubility of carbon dioxide in aqueous diethanolamine solutions was determined from the absorption rates measured in a near pseudo first-order reaction

H. HIKITA; S. ASAI; H. ISHIKAWA; K. UKU

1980-01-01

239

Beneficial Use of Carbon Dioxide in Precast Concrete Production  

SciTech Connect

The feasibility of using carbon dioxide as feedstock in precast concrete production is studied. Carbon dioxide reacts with calcium compounds in concrete, producing solid calcium carbonates in binding matrix. Two typical precast products are examined for their capacity to store carbon dioxide during the production. They are concrete blocks and fiber?cement panels. The two products are currently mass produced and cured by steam. Carbon dioxide can be used to replace steam in curing process to accelerate early strength, improve the long?term durability and reduce energy and emission. For a reaction within a 24?hour process window, the theoretical maximum possible carbon uptake in concrete is found to be 29% based on cement mass in the product. To reach the maximum uptake, a special process is developed to promote the reaction efficiency to 60?80% in 4?hour carbon dioxide curing and improve the resistance to freeze?thaw cycling and sulfate ion attack. The process is also optimized to meet the project target of $10/tCO{sub 2} in carbon utilization. By the use of self?concentrating absorption technology, high purity CO{sub 2} can be produced at a price below $40/t. With low cost CO{sub 2} capture and utilization technologies, it is feasible to establish a network for carbon capture and utilization at the vicinity of carbon sources. If all block produces and panel producers in United States could adopt carbon dioxide process in their production in place of steam, carbon utilization in these two markets alone could consume more than 2 Mt CO{sub 2}/year. This capture and utilization process can be extended to more precast products and will continue for years to come.

Shao, Yixin

2014-03-31

240

Miniaturized Amperometric Solid Electrolyte Carbon Dioxide Sensors  

NASA Technical Reports Server (NTRS)

A miniaturized electrochemical carbon dioxide (CO2) sensor using Na3Z r2Si2PO12 (NASICON) as a solid electrolyte has been fabricated and de monstrated. Microfabrication techniques were used for sensor fabricat ion to yield a sensing area around 1.0 mm x 1.1 mm. The NASICON solid electrolyte and the Na2CO3/BaCO3 (1:1.7 molar ratio) auxiliary elect rolyte were deposited by sputtering in between and on top of the inte rdigitated finger-shaped platinum electrodes. This structure maximize s the length of the three-phase boundary (electrode, solid electrolyt e, and auxiliary electrolyte), which is critical for gas sensing. The robust CO2 sensor operated up to 600 C in an amperometric mode and a ttempts were made to optimize sensor operating parameters. Concentrat ions of CO2 between 0.02% and 4% were detected and the overall sensor performance was evaluated. Linear response of sensor current output to ln[CO2 concentration] ranging from 0.02% to 1% was achieved.

Hunter, G. W.; Xu, J. C.; Liu, C. C.; Hammond, J. W.; Ward, B.; Lukco, D.; Lampard, P.; Artale, M.; Androjna, D.

2006-01-01

241

Development of Carbon Dioxide Hermitic Compressor  

NASA Astrophysics Data System (ADS)

Because of global environmental problems, the existing refrigerants are to be replaced with natural refrigerants. CO2 is one of the natural refrigerants and environmentally safe, inflammable and non-toxic refrigerant. Therefore high efficiency compressor that can operate with natural refrigerants, especially CO2, needs to be developed. We developed a prototype CO2 hermetic compressor, which is able to use in carbon dioxide refrigerating systems for practical use. The compressor has two rolling pistons, and it leads to low vibrations, low noise. In additions, two-stage compression with two cylinders is adopted, because pressure difference is too large to compress in one stage. And inner pressure of the shell case is intermediate pressure to minimize gas leakage between compressing rooms and inner space of shell case. Intermediate pressure design enabled to make the compressor smaller in size and lighter in weight. As a result, the compressor achieved high efficiency and high reliability by these technology. We plan to study heat pump water heater, cup vending machine and various applications with CO2 compressor.

Imai, Satoshi; Oda, Atsushi; Ebara, Toshiyuki

242

Zenker's Diverticulum: Carbon Dioxide Laser Endoscopic Surgery  

PubMed Central

Nowadays endoscopic diverticulotomy is the surgical approach of the first choice in treatment of Zenker's diverticulum. We report our experience with this procedure and try to sum up recent recommendations for management of surgery and postoperative care. Data of 34 patients with Zenker's diverticulum, treated by endoscopic carbon dioxide laser diverticulotomy at the Department of Otorhinolaryngology and Head and Neck Surgery, 1st Faculty of Medicine, Charles University, University Hospital Motol, Prague, Czech Republic, were prospectively stored and followed in relatively short period from May 2009 to December 2013. The average length of diverticulum was 32?mm. The average duration of surgery was 32?min. The patients were fed via feeding tube for 6.1 days and antibiotics were administered for 7 days. Mean hospitalization time was 7.4 days. We observed one transient recurrent laryngeal nerve paralysis and no other serious complications. Recurrence rate was 3%. We recommend complete transection of the diverticular septum in one procedure, systemic antibiotic treatment and exclusion of transoral intake for minimally 5 days, and contrast oesophagogram before resumption of oral intake to exclude fistula. Open diverticulectomy should be reserved for cases with inadequate endoscopic exposure and for revision surgery for multiple recurrences from endoscopic diverticulotomies. PMID:24729975

Plzk, Jan; Zbrodsk, Michal; Luke, Petr

2014-01-01

243

Euthanasia of neonatal mice with carbon dioxide  

USGS Publications Warehouse

Exposure to carbon dioxide (CO2) is the most prevalent method used to euthanize rodents in biomedical research. The purpose of this study was to determine the time of CO2 exposure required to euthanize neonatal mice (0 to 10 days old). Multiple groups of mice were exposed to 100% CO 2 for time periods between 5 and 60 min. Mice were placed in room air for 10 or 20 min after CO2 exposure, to allow for the chance of recovery. If mice recovered at one time point, a longer exposure was examined. Inbred and outbred mice were compared. Results of the study indicated that time to death varied with the age of the animals and could be as long as 50 min on the day of birth and differed between inbred and outbred mice. Institutions euthanizing neonatal mice with CO2 may wish to adjust their CO 2 exposure time periods according the age of the mice and their genetic background. Copyright 2005 by the American Association for Laboratory Animal Science.

Pritchett, K.; Corrow, D.; Stockwell, J.; Smith, A.

2005-01-01

244

Suppressing bullfrog larvae with carbon dioxide  

USGS Publications Warehouse

Current management strategies for the control and suppression of the American Bullfrog (Lithobates catesbeianus = Rana catesbeiana Shaw) and other invasive amphibians have had minimal effect on their abundance and distribution. This study evaluates the effects of carbon dioxide (CO2) on pre- and prometamorphic Bullfrog larvae. Bullfrogs are a model organism for evaluating potential suppression agents because they are a successful invader worldwide. From experimental trials we estimated that the 24-h 50% and 99% lethal concentration (LC50 and LC99) values for Bullfrog larvae were 371 and 549 mg CO2/L, respectively. Overall, larvae that succumbed to experimental conditions had a lower body condition index than those that survived. We also documented sublethal changes in blood chemistry during prolonged exposure to elevated CO2. Specifically, blood pH decreased by more than 0.5 pH units after 9 h of exposure and both blood partial pressure of CO2 (pCO2) and blood glucose increased. These findings suggest that CO2 treatments can be lethal to Bullfrog larvae under controlled laboratory conditions. We believe this work represents the necessary foundation for further consideration of CO2 as a potential suppression agent for one of the most harmful invaders to freshwater ecosystems.

Gross, Jackson A.; Ray, Andrew; Sepulveda, Adam J.; Watten, Barnaby J.; Densmore, Christine L.; Layhee, Megan J.; Mark Abbey-Lambert; Mark Abbey-Lambert

2014-01-01

245

Electrocatalytic Reduction of Carbon Dioxide to Methane  

NASA Technical Reports Server (NTRS)

A room-temperature electrocatalytic process that effects the overall chemical reaction CO2 + 2H2O yields CH4 + 2O2 has been investigated as a means of removing carbon dioxide from air and restoring oxygen to the air. The process was originally intended for use in a spacecraft life-support system, in which the methane would be vented to outer space. The process may also have potential utility in terrestrial applications in which either or both of the methane and oxygen produced might be utilized or vented to the atmosphere. A typical cell used to implement the process includes a polymer solid-electrolyte membrane, onto which are deposited cathode and anode films. The cathode film is catalytic for electrolytic reduction of CO2 at low overpotential. The anode film is typically made of platinum. When CO2 is circulated past the cathode, water is circulated past the anode, and a suitable potential is applied, the anode half-cell reaction is 4H2O yields 2O2 + 8H(+) + 8e(-). The H(+) ions travel through the membrane to the cathode, where they participate in the half-cell reaction CO2 + 8H(+) + 8e(-) yields CH4 + 2H2O.

Sammells, Anthony F.; Spiegel, Ella F.

2008-01-01

246

Carbon dioxide balneotherapy and cardiovascular disease  

NASA Astrophysics Data System (ADS)

Carbon dioxide (CO2) balneotherapy is a kind of remedy with a wide spectrum of applications which have been used since the Middle Ages. However, its potential use as an adjuvant therapeutic option in patients with cardiovascular disease is not yet fully clarified. We performed a thorough review of MEDLINE Database, EMBASE, ISI WEB of Knowledge, COCHRANE database and sites funded by balneotherapy centers across Europe in order to recognize relevant studies and aggregate evidence supporting the use of CO2 baths in various cardiovascular diseases. The three main effects of CO2 hydrotherapy during whole body or partial immersion, including decline in core temperature, an increase in cutaneous blood flow, and an elevation of the score on thermal sensation, are analyzed on a pathophysiology basis. Additionally, the indications and contra-indications of the method are presented in an evidence-based way, while the need for new methodologically sufficient studies examining the use of CO2 baths in other cardiovascular substrates is discussed.

Pagourelias, Efstathios D.; Zorou, Paraskevi G.; Tsaligopoulos, Miltiadis; Athyros, Vasilis G.; Karagiannis, Asterios; Efthimiadis, Georgios K.

2011-09-01

247

Effects of carbon dioxide on laryngeal receptors  

SciTech Connect

Carbon dioxide (CO{sub 2}) either stimulates or inhibits laryngeal receptors in the cat. The aim of this study was to correlate the CO{sub 2} response of laryngeal receptors with their response to other known stimuli (i.e. pressure, movement, cold, water and smoke). Single unit action potentials were recorded from fibers in the superior laryngeal nerve of 5 anesthetized, spontaneously breathing dogs together with CO{sub 2} concentration, esophageal and subglottic pressure. Constant streams of warm, humidified air or 10% CO{sub 2} in O{sub 2} were passed through the functionally isolated upper airway for 60 s. Eight of 13 randomly firing or silent receptors were stimulated by CO{sub 2} (from 0.4{plus minus}0.1 to 1.8{plus minus}0.4 imp.s). These non-respiratory-modulated receptors were more strongly stimulated by solutions lacking Cl{sup {minus}} and/or cigarette smoke. Six of 21 respiratory modulated receptors (responding to pressure and/or laryngeal motion) were either inhibited or stimulated by CO{sub 2}. Our results show that no laryngeal receptor responds only to CO{sub 2}. Silent or randomly active receptors were stimulated most often by CO{sub 2} consistent with the reflex effect of CO{sub 2} in the larynx.

Anderson, J.W.; Sant'Ambrogio, F.B.; Orani, G.P.; Sant'Ambrogio, G.; Mathew, O.P. (Univ. of Texas, Galveston (United States))

1990-02-26

248

Heliox Improves Carbon Dioxide Removal during Lung Protective Mechanical Ventilation  

PubMed Central

Introduction. Helium is a noble gas with low density and increased carbon dioxide (CO2) diffusion capacity. This allows lower driving pressures in mechanical ventilation and increased CO2 diffusion. We hypothesized that heliox facilitates ventilation in patients during lung-protective mechanical ventilation using low tidal volumes. Methods. This is an observational cohort substudy of a single arm intervention study. Twenty-four ICU patients were included, who were admitted after a cardiac arrest and mechanically ventilated for 3 hours with heliox (50% helium; 50% oxygen). A fixed protective ventilation protocol (6?mL/kg) was used, with prospective observation for changes in lung mechanics and gas exchange. Statistics was by Bonferroni post-hoc correction with statistical significance set at P < 0.017. Results. During heliox ventilation, respiratory rate decreased (25 4 versus 23 5 breaths?min?1, P = 0.010). Minute volume ventilation showed a trend to decrease compared to baseline (11.1 1.9 versus 9.9 2.1?L?min?1, P = 0.026), while reducing PaCO2 levels (5.0 0.6 versus 4.5 0.6?kPa, P = 0.011) and peak pressures (21.1 3.3 versus 19.8 3.2?cm H2O, P = 0.024). Conclusions. Heliox improved CO2 elimination while allowing reduced minute volume ventilation in adult patients during protective mechanical ventilation.

Beurskens, Charlotte J.; Brevoord, Daniel; Lagrand, Wim K.; van den Bergh, Walter M.; Vroom, Margreeth B.; Preckel, Benedikt; Horn, Janneke; Juffermans, Nicole P.

2014-01-01

249

The role of renewable bioenergy in carbon dioxide sequestration  

SciTech Connect

The use of renewable resources represents a sound approach to producing clean energy and reducing the dependence on diminishing reserves of fossil fuels. Unfortunately, the widespread interest in renewable energy in the 1970s, spurred by escalating fossil fuel prices, subsided with the collapse of energy prices in the mid 1980s. Today, it is largely to reverse alarming environmental trends, particularly the buildup of atmospheric carbon dioxide, rather than to reduce the cost of energy, that renewable energy resources are being pursued. This discussion focuses on a specific class of renewable energy resources - biomass. Unlike most other classes of renewable energy touted for controlling atmospheric carbon dioxide concentrations, e.g., hydro, direct solar, wind, geothermal, and ocean thermal, which produce usable forms of energy while generating little or no carbon dioxide emissions, bioenergy almost always involves combustion and therefore generates carbon dioxide; however, if used on a sustained basis, bio-energy would not contribute to the build-up of atmospheric carbon dioxide because the amount released in combustion would be balanced by that taken up via photosynthesis. It is in that context, i.e., sustained production of biomass as a modern energy carrier, rather than reforestation for carbon sequestration, that biomass is being discussed here, since biomass can play a much greater role in controlling global warming by displacing fossil fuels than by being used strictly for carbon sequestration (partly because energy crop production can reduce fossil carbon dioxide emissions indefinitely, whereas under the reforestation strategy, carbon dioxide abatement ceases at forest maturity).

Kinoshita, C.M. [Hawaii Natural Energy Inst., Honolulu, HI (United States)

1993-12-31

250

A 400 million year carbon isotope record of pedogenic carbonate: Implications for paleoatmospheric carbon dioxide  

Microsoft Academic Search

A 400 record of atmospheric carbon dioxide levels has been estimated by applying a CO paleobarometer to a database of 758 analyses of paleosol (fossil soil) carbonates. This database is a compilation of new data and previously published values from the literature. Many new analyses of Mesozoic paleosols are reported, an era poorly represented in the literature. Results indicate that

D. D. Ekart; T. E. Cerling; I. P. Montanez; N. J. Tabor

1999-01-01

251

A selective and efficient electrocatalyst for carbon dioxide reduction  

NASA Astrophysics Data System (ADS)

Converting carbon dioxide to useful chemicals in a selective and efficient manner remains a major challenge in renewable and sustainable energy research. Silver is an interesting electrocatalyst owing to its capability of converting carbon dioxide to carbon monoxide selectively at room temperature; however, the traditional polycrystalline silver electrocatalyst requires a large overpotential. Here we report a nanoporous silver electrocatalyst that is able to electrochemically reduce carbon dioxide to carbon monoxide with approximately 92% selectivity at a rate (that is, current) over 3,000 times higher than its polycrystalline counterpart under moderate overpotentials of <0.50?V. The high activity is a result of a large electrochemical surface area (approximately 150 times larger) and intrinsically high activity (approximately 20 times higher) compared with polycrystalline silver. The intrinsically higher activity may be due to the greater stabilization of CO2?- intermediates on the highly curved surface, resulting in smaller overpotentials needed to overcome the thermodynamic barrier.

Lu, Qi; Rosen, Jonathan; Zhou, Yang; Hutchings, Gregory S.; Kimmel, Yannick C.; Chen, Jingguang G.; Jiao, Feng

2014-01-01

252

CARBON DIOXIDE CAPTURE FROM FLUE GAS USING DRY REGENERABLE SORBENTS  

SciTech Connect

This report describes research conducted between April 1, 2004 and June 30, 2004 on the preparation and use of dry regenerable sorbents for removal of carbon dioxide from flue gas. Support materials and supported sorbents were prepared by spray drying. Sorbents consisting of 20 to 50% sodium carbonate on a ceramic support were prepared by spray drying in batches of approximately 300 grams. The supported sorbents exhibited greater carbon dioxide capture rates than unsupported calcined sodium bicarbonate in laboratory tests. Preliminary process design and cost estimation for a retrofit application suggested that costs of a dry regenerable sodium carbonate-based process could be lower than those of a monoethanolamine absorption system. In both cases, the greatest part of the process costs come from power plant output reductions due to parasitic consumption of steam for recovery of carbon dioxide from the capture medium.

David A. Green; Brian S. Turk; Jeffrey W. Portzer; Raghubir P. Gupta; William J. McMichael; Thomas Nelson

2004-07-01

253

Interaction of Surface Modified Carbon Nanotubes with Supercritical Carbon Dioxide  

NASA Astrophysics Data System (ADS)

The properties of carbon nanotube (CNT)-polymer nanocomposites are far below than those calculated, mainly due to poor dispersion or interface quality. This is particularly difficult for single walled carbon nanotubes (SWNTs) as they tend to form bundles or ropes that are difficult to exfoliate. Supercritical fluid (SCF) assisted processing is one of the methods that can be used to exfoliate/disperse CNTs along with modifiying the interface of the CNTs. Molecular dynamics simulations were performed to understand how the surface modifiers behave near SWNT surface with and without the presence of SCF molecules. It is also important to understand the diffusivity of SCF molecules between SWNT bundles and the effect of surface modifiers on diffusion. Octane and n-perflourooctane molecules were used as surface modifiers with varying tethering density and carbon dioxide (CO2) was chosen as the SCF. Results showed that the system with highest number of n-perfluorooctanes presented the highest degree of success in separating the SWNTs in the presence of CO2.

Baysal, Nihat; Unsal, Banu; Ozisik, Rahmi

2006-03-01

254

Master/Diploma project Degradation of carbon dioxide by micro organisms  

E-print Network

microorganisms can use carbon dioxide as carbon source for their life cycle. Whereas plants are the main sourceMaster/Diploma project Degradation of carbon dioxide by micro organisms The accumulation of carbon of the carbon dioxide release is an important objective in the near future. Various strategies are discussed

Rostock, Universität

255

Ionic Liquid Membranes for Carbon Dioxide Separation  

SciTech Connect

Recent scientific studies are rapidly advancing novel technological improvements and engineering developments that demonstrate the ability to minimize, eliminate, or facilitate the removal of various contaminants and green house gas emissions in power generation. The Integrated Gasification Combined Cycle (IGCC) shows promise for carbon dioxide mitigation not only because of its higher efficiency as compared to conventional coal firing plants, but also due to a higher driving force in the form of high partial pressure. One of the novel technological concepts currently being developed and investigated is membranes for carbon dioxide (CO2) separation, due to simplicity and ease of scaling. A challenge in using membranes for CO2 capture in IGCC is the possibility of failure at elevated temperatures or pressures. Our earlier research studies examined the use of ionic liquids on various supports for CO2 separation over the temperature range, 37C-300C. The ionic liquid, 1-hexyl-3methylimidazolium Bis(trifluoromethylsulfonyl)imide, ([hmim][Tf2N]), was chosen for our initial studies with the following supports: polysulfone (PSF), poly(ether sulfone) (PES), and cross-linked nylon. The PSF and PES supports had similar performance at room temperature, but increasing temperature caused the supported membranes to fail. The ionic liquid with the PES support greatly affected the glass transition temperature, while with the PSF, the glass transition temperature was only slightly depressed. The cross-linked nylon support maintained performance without degradation over the temperature range 37-300C with respect to its permeability and selectivity. However, while the cross-linked nylon support was able to withstand temperatures, the permeability continued to increase and the selectivity decreased with increasing temperature. Our studies indicated that further testing should examine the use of other ionic liquids, including those that form chemical complexes with CO2 based on amine interactions. The hypothesis is that the performance at the elevated temperatures could be improved by allowing a facilitated transport mechanism to become dominant. Several amine-based ionic liquids were tested on the cross-linked nylon support. It was found that using the amine-based ionic liquid did improve selectivity and permeability at higher temperature. The hypothesis was confirmed, and it was determined that the type of amine used also played a role in facilitated transport. Given the appropriate aminated ionic liquid with the cross-linked nylon support, it is possible to have a membrane capable of separating CO2 at IGCC conditions. With this being the case, the research has expanded to include separation of other constituents besides CO2 (CO, H2S, etc.) and if they play a role in membrane poisoning or degradation. This communication will discuss the operation of the recently fabricated ionic liquid membranes and the impact of gaseous components other than CO2 on their performance and stability.

Myers, C.R.; Ilconich, J.B.; Luebke, D.R.; Pennline, H.W.

2008-07-12

256

14 April 2001 tmospheric carbon dioxide  

E-print Network

emissions is through increased carbon sequestration into forests. In a large-scale assessment, Birdsey- ing carbon sequestration in southern forests. Carbon sequestration via southern pine forests may policy commitments. Keywords: carbon sequestration; southern pine forests ABSTRACT MEETING GLOBAL POLICY

Teskey, Robert O.

257

The carbon dioxide challenge facing aviation  

NASA Astrophysics Data System (ADS)

This paper investigates the challenge that U.S. aviation would face in meeting future Greenhouse Gas (GHG) reduction goals to mitigate global climate change via technological options. This investigation is done within a framework that considers aviation GHG emissions as a function of aviation growth, aircraft efficiency, operational efficiency, and life cycle GHG emissions of aviation fuels. The concept of life cycle GHG intensity (LGI) with units of grams carbon dioxide equivalent per payload distance traveled is used for this purpose as it can be decomposed into components that quantify improvements in aircraft design, operations, and alternative fuels. For example, the life cycle GHG intensity of U.S. aviation in 2005 was 1.37 g CO2e/kg km. If U.S. aviation is to meet the IATA 2050 goal of a 50% reduction in CO2 relative to a 2005 baseline while allowing for a 3.2% annual growth rate in payload-distance traveled, it will need to decrease to 0.22 g CO2e/kg km in 2050, an 84% reduction. The analysis framework that is developed in this manuscript was used to compare the improvements in life cycle GHG intensity that could accompany the use of advanced aircraft designs, operational improvements, and alternative fuels to those required on a fleet-wide basis to meet the future GHG reduction goals under varied aviation growth scenarios. The results indicate that the narrow body segment of the fleet could indeed meet ambitious goals of reducing GHG emissions by 50%, relative to 2005 levels, with a 3.2% annual growth rate; however, it would require relatively rapid adoption of innovative aircraft designs and the widespread use of alternative fuels with relatively low life cycle GHG emissions.

Hileman, James I.; De la Rosa Blanco, Elena; Bonnefoy, Philippe A.; Carter, Nicholas A.

2013-11-01

258

The Headache of Carbon Dioxide Exposures  

NASA Technical Reports Server (NTRS)

Carbon dioxide (CO2), a natural product of human metabolism, accumulates quickly in sealed environments when humans are present, and can induce headaches, among other symptoms. Major resources are expended to control CO2 levels to concentrations that are tolerable to the crews of spacecraft and submersible craft. It is not practical to control CO2 levels to those found in the ambient environment on earth. As NASA looks ahead to long-duration missions conducted far from earth, difficult issues arise related to the management and effects of human exposure to CO2. One is the problem of pockets of CO2 in the habitat caused by excess generation of the gas in one location without a mechanism to purge the area with fresh air. This results in the crew rebreathing CO2 from their exhaled breath, exposing them to a much higher concentration of CO2 than whole-module measurements would suggest. Another issue is the potential increased sensitivity to CO2 in microgravity. For example, based on anecdotal information, it appears that space crews may be more susceptible than submarine crews to some of the subtle, yet adverse effects of CO2 exposure. Another issue, not unique to spaceflight, is the possibility of inter-individual differences in the susceptibility of crewmembers to CO2 exposure. Again, anecdotal reports from the International Space Station (ISS) crews suggest that certain individuals may experience a greater susceptibility. The implications associated with these issues are extremely important as NASA sets CO2 exposure limits that protect the crew from this compound s subtle adverse effects, without causing an unwarranted expenditure of resources to scrub CO2 from the habitat atmosphere.

James, John T.

2007-01-01

259

Carbon dioxide exchange in a peatland ecosystem  

NASA Astrophysics Data System (ADS)

Micrometeorological measurements of carbon dioxide exchange were made in an open peatland in north central Minnesota during two growing seasons (1991 and 1992). The vegetation at the site was dominated by Sphagnum papillosum, Scheuchzeria palustris, and Chamaedaphne calyculata. The objective of the study was to examine the diurnal and seasonal variations in canopy photosynthesis (P) and develop information on the net ecosystem CO2 exchange. The two seasons provided contrasting microclimatic conditions: as compared with 1991, the 1992 season was significantly wetter and cooler. Canopy photosynthesis was sensitive to changes in light, temperature, and moisture stress (as indicated by water table depth and atmospheric vapor pressure deficit). Under moderate conditions (temperature 18-28C, vapor pressure deficit 0.7-1.5 kPa, and water table near the surface) during the peak growth period, midday (averaged between 1000-1400 hours) P values ranged from 0.15 to 0.24 mg m-2 s-1. Under high-temperature (30-34C) and moisture stress (water table 0.16-0.23 m below the surface and vapor pressure deficit 2.2-3.0 kPa) conditions, midday P was reduced to about 0.03-0.06 mg m-2 s-1. There was a high degree of consistency in the values of P under similar conditions in the two seasons. Seasonally integrated values of the daily net ecosystem CO2 exchange indicated that the study site was a source of atmospheric CO2, releasing about 71 g C m-2 over a 145-day period (May-October) in 1991. Over a similar period in 1992, however, this ecosystem was a sink for atmospheric CO2 with a net accumulation of about 32 g C m-2. These results are consistent with previous investigations on CO2 exchange in other northern wetland sites during wet and dry periods.

Shurpali, N. J.; Verma, S. B.; Kim, J.; Arkebauer, T. J.

1995-07-01

260

Carbon Dioxide Carbonates in the Earth;s Mantle: Implications to the Deep Carbon Cycle  

SciTech Connect

An increase in the ionic character in C-O bonds at high pressures and temperatures is shown by the chemical/phase transformation diagram of CO{sub 2}. The presence of carbonate carbon dioxide (i-CO{sub 2}) near the Earth's core-mantle boundary condition provides insights into both the deep carbon cycle and the transport of atmospheric CO{sub 2} to anhydrous silicates in the mantle and iron core.

Yoo, Choong-Shik; Sengupta, Amartya; Kim, Minseob (Princeton); (WSU)

2012-05-22

261

Persistent local order heterogeneity in the supercritical carbon dioxide  

E-print Network

The supercritical state is currently viewed as uniform and homogeneous on the pressure-temperature phase diagram in terms of physical properties. Here, we study structural properties of the supercritical carbon dioxide, and discover the existence of persistent medium-range order correlations which make supercritical carbon dioxide non-uniform and heterogeneous on an intermediate length scale, a result not hitherto anticipated. We report on the carbon dioxide heterogeneity shell structure where, in the first shell, both carbon and oxygen atoms experience gas-like type inter- actions with short range order correlations, while within the second shell oxygen atoms essentially exhibit liquid-like type of interactions with medium range order correlations due to localisation of transverse-like phonon packets. We show that the local order heterogeneity remains in the three phase-like equilibrium within very wide temperature range. Importantly, we highlight a catalytic role of atoms inside the nearest neighbor heterogeneity shell in providing a mechanism for diffusion in the supercritical carbon dioxide on an intermediate length scale. Finally, we discuss important implications for answering the intriguing question whether Venus may have had carbon dioxide oceans and urge for an experimental detection of this persistent local order heterogeneity.

Dima Bolmatov; D. Zav'yalov; M. Gao; M. Zhernenkov

2014-06-06

262

Mar., 1955 GASIFICATIONOF CARBONRODSWITH CARBONDIOXIDE 241 GASIFICATION OF CARBON RODS WITH CARBON DIOXIDE1*2  

E-print Network

Mar., 1955 GASIFICATIONOF CARBONRODSWITH CARBONDIOXIDE 241 GASIFICATION OF CARBON RODS WITH CARBON commercial carbons and their gasification rates with carbon dioxide at a series of temperatures between 900. No general correlation between these properties and the carbon gasification rates was found. Introduction

263

Cobalt carbonyl catalyzed olefin hydroformylation in supercritical carbon dioxide  

DOEpatents

A method of olefin hydroformylation is provided wherein an olefin reacts with a carbonyl catalyst and with reaction gases such as hydrogen and carbon monoxide in the presence of a supercritical reaction solvent, such as carbon dioxide. The invention provides higher yields of n-isomer product without the gas-liquid mixing rate limitation seen in conventional Oxo processes using liquid media.

Rathke, J.W.; Klingler, R.J.

1993-03-30

264

Capturing carbon dioxide as a polymer from natural gas  

NASA Astrophysics Data System (ADS)

Natural gas is considered the cleanest and recently the most abundant fossil fuel source, yet when it is extracted from wells, it often contains 10-20?mol% carbon dioxide (20-40?wt%), which is generally vented to the atmosphere. Efforts are underway to contain this carbon dioxide at the well-head using inexpensive and non-corrosive methods. Here we report nucleophilic porous carbons are synthesized from simple and inexpensive carbon-sulphur and carbon-nitrogen precursors. Infrared, Raman and 13C nuclear magnetic resonance signatures substantiate carbon dioxide fixation by polymerization in the carbon channels to form poly(CO2) under much lower pressures than previously required. This growing chemisorbed sulphur- or nitrogen-atom-initiated poly(CO2) chain further displaces physisorbed hydrocarbon, providing a continuous carbon dioxide selectivity. Once returned to ambient conditions, the poly(CO2) spontaneously depolymerizes, leading to a sorbent that can be easily regenerated without the thermal energy input that is required for traditional sorbents.

Hwang, Chih-Chau; Tour, Josiah J.; Kittrell, Carter; Espinal, Laura; Alemany, Lawrence B.; Tour, James M.

2014-06-01

265

Capturing carbon dioxide as a polymer from natural gas.  

PubMed

Natural gas is considered the cleanest and recently the most abundant fossil fuel source, yet when it is extracted from wells, it often contains 10-20 mol% carbon dioxide (20-40 wt%), which is generally vented to the atmosphere. Efforts are underway to contain this carbon dioxide at the well-head using inexpensive and non-corrosive methods. Here we report nucleophilic porous carbons are synthesized from simple and inexpensive carbon-sulphur and carbon-nitrogen precursors. Infrared, Raman and (13)C nuclear magnetic resonance signatures substantiate carbon dioxide fixation by polymerization in the carbon channels to form poly(CO2) under much lower pressures than previously required. This growing chemisorbed sulphur- or nitrogen-atom-initiated poly(CO2) chain further displaces physisorbed hydrocarbon, providing a continuous carbon dioxide selectivity. Once returned to ambient conditions, the poly(CO2) spontaneously depolymerizes, leading to a sorbent that can be easily regenerated without the thermal energy input that is required for traditional sorbents. PMID:24892923

Hwang, Chih-Chau; Tour, Josiah J; Kittrell, Carter; Espinal, Laura; Alemany, Lawrence B; Tour, James M

2014-01-01

266

Electrostatic Stabilization of Colloids in Carbon Dioxide: Electrophoresis and Dielectrophoresis  

E-print Network

Electrostatic Stabilization of Colloids in Carbon Dioxide: Electrophoresis and Dielectrophoresis by electrostatic forces, despite the ultralow dielectric constant of 1.5. Zeta potentials of micrometer- sized a dozen droplets with lengths of 50 m. The ability to form electrostatically stabilized colloids in carbon

267

Distribution of and changes in industrial carbon dioxide production  

Microsoft Academic Search

The burning of fossils fuels is believed to be the major source responsible for an observed increase in the concentration of carbon dioxide in the atmosphere now measured at many locations around the world. This paper revises earlier published data on the annual amounts of carbon released to the atmosphere during the period 1950--1978 and updates the record through 1980.

Ralph M. Rotty

1983-01-01

268

II. Greenhouse gas markets, carbon dioxide credits and biofuels17  

E-print Network

15 II. Greenhouse gas markets, carbon dioxide credits and biofuels17 The previous chapter analysed biofuels production. GHG policies18 that create a carbon price either through an emissions trading system or directly by taxing GHG emissions also generate increased demand for biofuels. They do so by raising

269

CARBON DIOXIDE CAPTURE FROM FLUE GAS USING DRY REGENERABLE SORBENTS  

SciTech Connect

The objective of this project is to develop a simple and inexpensive process to separate CO{sub 2} as an essentially pure stream from a fossil fuel combustion system using a regenerable sorbent. The sorbents being investigated in this project are primarily alkali carbonates, and particularly sodium carbonate and potassium carbonate, which are converted to bicarbonates through reaction with carbon dioxide and water vapor. Bicarbonates are regenerated to carbonates when heated, producing a nearly pure CO{sub 2} stream after condensation of water vapor. This quarter, electrobalance tests suggested that higher temperature calcination of trona leds to reduced carbonation activity in subsequent cycles, but that calcination in dry carbon dioxide did not result in decreased activity relative to calcination in helium. Following higher temperature calcination, sodium bicarbonate (SBC) No.3 has greater activity than either coarse or fine grades of trona. Fixed bed testing of calcined SBC No.3 at 70 C confirmed that high rates of carbon dioxide absorption are possible and that the resulting product is a mixture of Wegscheider's salt and sodium carbonate. In fluidized bed testing of supported potassium carbonate, very rapid carbonation rates were observed. Activity of the support material complicated the data analysis. A milled, spherical grade of SBC appeared to be similar in attrition and abrasion characteristics to an unmilled, less regularly shaped SBC. The calcination behavior, at 107 C, for the milled and unmilled materials was also similar.

David A. Green; Brian S. Turk; Jeffrey W. Portzer; Raghubir P.Gupta; William J. McMichael; Ya Liang; Douglas P. Harrison

2002-10-01

270

Carbon Dioxide Effects Research and Assessment Program. Carbon Dioxide Research Progress Report, fiscal year 1979  

SciTech Connect

Research on the global carbon cycle and the effects of increased carbon dioxide on the global climate system is reported. Environmental and societal effects related to CO/sub 2/ and environmental control technology for CO/sub 2/ are also discussed. Lists of research projects and reports and publications of the Carbon Dioxide and Climate Research Program are included. An expanded CO/sub 2/ monitoring network is providing increased coverage for interpretation of patterns of sources and sinks seasonal variability, and documentation of the global growth of CO/sub 2/. Modeling studies emphasized that knowledge of the transport and mixing of surface ocean waters is important in understanding deep oceanic circulation. Initial studies in the equatorial Pacific are helping quantify estimates of the amount of outgassing CO/sub 2/ from tropical waters. During fiscal year 1979, there was a substantial increase in appreciation of the role of the ocean in controlling not only atmospheric CO/sub 2/ concentrations but also the climatic response to changes in concentration. Model simulations of the effect of doubled CO/sub 2/ concentration carried out with fixed ocean temperatures a situation that is possible during perhaps the next 20 years, showed relatively small summer heating over land areas. On the other hand, simulations in which the oceanic temperatures could come into instantaneous equilibrium with atmospheric conditions continued to show global temperature increases of 3 +- 1.5/sup 0/C, accentuated at high latitudes. To improve understanding of possible regional climate changes, there were increased efforts to reconstruct regional climatic patterns prevailing during past warm periods that might serve as analogs of future climatic conditions. Particular attention was directed to the climates of the United States and other countries bordering the North Atlantic Ocean during the warm period 5000 to 7000 years ago.

Dahlman, R.C.; Gross, T.; Machta, L.; Elliott, W.; MacCracken, M.

1980-04-01

271

Persistent local order heterogeneity in the supercritical carbon dioxide  

E-print Network

The supercritical state is currently viewed as uniform and homogeneous on the pressure-temperature phase diagram in terms of physical properties. Here, we study structural properties of the supercritical carbon dioxide, and discover the existence of persistent medium-range order correlations which make supercritical carbon dioxide non-uniform and heterogeneous on an intermediate length scale, a result not hitherto anticipated. We report on the carbon dioxide heterogeneity shell structure where, in the first shell, both carbon and oxygen atoms experience gas-like type inter- actions with short range order correlations, while within the second shell oxygen atoms essentially exhibit liquid-like type of interactions with medium range order correlations due to localisation of transverse-like phonon packets. We show that the local order heterogeneity remains in the three phase-like equilibrium within very wide temperature range. Importantly, we highlight a catalytic role of atoms inside the nearest neighbor heterog...

Bolmatov, Dima; Gao, M; Zhernenkov, M

2014-01-01

272

Geologic sequestration of carbon dioxide - an energy resource perspective  

SciTech Connect

Most energy used to meet human needs is derived from the combustion of fossil fuels (natural gas, oil, and coal), which releases carbon to the atmosphere, primarily as carbon dioxide (CO{sub 2}). The atmospheric concentration of CO{sub 2}, a greenhouse gas, is increasing, raising concerns that solar heat will be trapped and the average surficial temperature of the Earth will rise in response. Global warming studies predict that climate changes resulting from increases in atmospheric CO{sub 2} will adversely affect life on Earth. In the 200 years since the industrial revolution, the world's population has grown from about 800 million to over 6 billion people and the CO{sub 2} content of the atmosphere has risen from about 280 to about 360 parts per million by volume, a 30 percent increase. International concern about potential global climate change has spurred discussions about limiting the amount of CO{sub 2} and other greenhouse gases released to the atmosphere. 1 ref., 3 figs.

Robert C. Burruss; Sean T. Brennan

2003-03-15

273

Carbon dioxide consumption during soil development  

Microsoft Academic Search

Carbon is sequestered in soils by accumulation of recalcitrant organic matter and by bicarbonate weathering of silicate minerals. Carbon fixation by ecosystems helps drive weathering processes in soils and that in turn diverts carbon from annual photosynthesis-soil respiration cycling into the long-term geological carbon cycle. To quantify rates of carbon transfer during soil development in moist temperate grassland and desert

Oliver A. Chadwick; Eugene F. Kelly; Dorothy M. Merritts; Ronald G. Amundson

1994-01-01

274

Interference of oxygen, carbon dioxide, and water vapor on the analysis for oxides of nitrogen by chemiluminescence  

NASA Technical Reports Server (NTRS)

The interference of small concentrations (less than 4 percent by volume) of oxygen, carbon dioxide, and water vapor on the analysis for oxides of nitrogen by chemiluminescence was measured. The sample gas consisted primarily of nitrogen, with less than 100 parts per million concentration of nitric oxide, and with small concentrations of oxygen, carbon dioxide, and water vapor added. Results obtained under these conditions indicate that although oxygen does not measurably affect the analysis for nitric oxide, the presence of carbon dioxide and water vapor causes the indicated nitric oxide concentration to be too low. An interference factor - defined as the percentage change in indicated nitric oxide concentration (relative to the true nitric oxide concentration) divided by the percent interfering gas present - was determined for carbon dioxide to be -0.60 + or - 0.04 and for water vapor to be -2.1 + or - 0.3.

Maahs, H. G.

1975-01-01

275

Modeling the diffusion effects through the iron carbonate layer in the carbon dioxide corrosion of carbon steel  

SciTech Connect

A mechanistic model was developed for predicting carbon dioxide corrosion rates of carbon steel pipes in multiphase flow conditions. The model incorporates the chemistry, thermodynamics of carbon dioxide dissolution, multiphase mass transfer, electrochemical kinetics on the metal surface and the presence of a corrosion product film. The predicted corrosion rates show good agreement with the experimental results.

Rajappa, S.; Zhang, R.; Gopal, M. [Ohio Univ., Athens, OH (United States)

1998-12-31

276

Predator-induced reduction of freshwater carbon dioxide emissions  

NASA Astrophysics Data System (ADS)

Predators can influence the exchange of carbon dioxide between ecosystems and the atmosphere by altering ecosystem processes such as decomposition and primary production, according to food web theory. Empirical knowledge of such an effect in freshwater systems is limited, but it has been suggested that predators in odd-numbered food chains suppress freshwater carbon dioxide emissions, and predators in even-numbered food chains enhance emissions. Here, we report experiments in three-tier food chains in experimental ponds, streams and bromeliads in Canada and Costa Rica in the presence or absence of fish (Gasterosteus aculeatus) and invertebrate (Hesperoperla pacifica and Mecistogaster modesta) predators. We monitored carbon dioxide fluxes along with prey and primary producer biomass. We found substantially reduced carbon dioxide emissions in the presence of predators in all systems, despite differences in predator type, hydrology, climatic region, ecological zone and level of in situ primary production. We also observed lower amounts of prey biomass and higher amounts of algal and detrital biomass in the presence of predators. We conclude that predators have the potential to markedly influence carbon dioxide dynamics in freshwater systems.

Atwood, Trisha B.; Hammill, Edd; Greig, Hamish S.; Kratina, Pavel; Shurin, Jonathan B.; Srivastava, Diane S.; Richardson, John S.

2013-03-01

277

The influence of soil crusting on carbon dioxide emissions from soil  

NASA Astrophysics Data System (ADS)

Global soils contain an estimated 1500GT of carbon, over twice that present in the atmosphere, however the role of soil in the global carbon cycle is highly debated. The influence of soil erosion and deposition in the global carbon cycle has been primarily investigated through the incubation of small volumes of loose sediment. The physical properties of this sediment are likely to differ to those in the environment where in situ soil forms part of an intact unit which can have a cohesive high density crust at the surface. The primary aim of this investigation was to measure carbon dioxide emissions from intact crusted soil samples. Rainfall simulation was used to create areas of soil crusting under high and low rainfall intensity in areas of erosion and deposition. The carbon dioxide emissions were measured over a 58 day period using an Infra Red Gas Analyser (IRGA). Physical properties of the crusts (total C content, C:N ratio, texture, density, degree of aggregation) were also determined. It was found that CO2 emissions were not related to C content alone, with strong correlation found to density (rs - 0.70) and aggregation (rs - 0.67), and texture also being influential although to a lesser extent. It is the effect that these properties have on OM bioavailability and gas diffusivity which affects the emissions of carbon dioxide. The physical properties of a crust are influenced by rainfall intensity, a conceptual diagram explaining this process has been developed. Given the strong correlation that has been found between carbon dioxide emissions and the physical properties of soils to base estimates of emissions on studies of loose samples maybe flawed. Furthermore given that rainfall intensity is predicted to change with global warming so to may soil crusting and emissions of carbon dioxide.

Armstrong, Elizabeth; Quinton, John; Kuhn, Nikolaus

2010-05-01

278

SCORR - supercritical carbon dioxide resist removal.  

SciTech Connect

SCORR, short for supercritical carbon dioxide resist removal, is a new technology that could continue to enable the technological development of photolithography processes in industry. SCORR is based upon the physical properties of supercritical fluids (SCFs). These special properties enable SCFs to remove coatings, residues, and particles froin high-aspect-ratio structures in integrated circuits (ICs). SCORR also eliminates rinsing and drying steps presently used in IC manufacture, thereby eliminating the generation of millions of gallons of water per fab per day. Fabricating integrated circuits relies heavily on photolithography to define the shape and pattern of individual components. Once a single stage of a silicon wafer's topography has been completed, the hardened resist must be removed. Conventional processes generates more waste than any single step in the IC manufacturing process, and the production of a complete IC can involve many photolithography iterations. The cost associated with the treatment and disposal of this waste, as well as employee health and safety considerations, are driving a search for a1 ternative, environmentally benign, cost-effective solutions. In addition, photoresist stripping is confronting finer architectures and higher aspect ratios, as well as new low-k materials that are highly sensitive to post-etch residue. Low-k dielectrics and low-resistivity conductors such as copper are necessary for meeting industry's need for faster and smaller chips. Further, each low-k choice requires different plasma-etching processes, or chemistries, to etch structures into the low-k material; therefore, the nature of the residues can be different. No one product can meet all copper/low-k applications, and existing chemistries are not tunable - or even desirable - for the new processes. We have developed a new process - known as SCORR - that removes photoresist and post-ash, -etch, and -CMP (particulate) residue from semiconductor wafers. As IC feature sizes become smaller, the need for ensuring particle removal will increase. With feature sizes of less than 0.18{micro}m, it will become imperative that all particles greater than about 0.1 micron be removed from the semiconductor wafer. Existing cleaning technologies (such as liquid or high-pressure jet scrubbing) cannot remove particles on the order of 0.1 micron because of surface boundary layer constraints. Because of the low viscosities of supercritical fluids (SCFs), these constraints are virtually eliminated.

Jacobson, G. B. (Gunilla B.); Williams, L. L. (Laurie L.); Hollis, W. K. (William K.); Barton, Jerome C.; Taylor, C. M. (Craig M.)

2002-01-01

279

Direct carbon dioxide emissions from civil aircraft  

NASA Astrophysics Data System (ADS)

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

Grote, Matt; Williams, Ian; Preston, John

2014-10-01

280

Carbon dioxide as a carbon source in organic transformation: carbon-carbon bond forming reactions by transition-metal catalysts.  

PubMed

Recent carbon-carbon bond forming reactions of carbon dioxide with alkenes, alkynes, dienes, aryl zinc compounds, aryl boronic esters, aryl halides, and arenes having acidic C-H bonds are reviewed in which transition-metal catalysts play an important role. PMID:22859266

Tsuji, Yasushi; Fujihara, Tetsuaki

2012-10-14

281

Water and Carbon Dioxide Adsorption at Olivine Surfaces  

SciTech Connect

Plane-wave density functional theory (DFT) calculations were performed to simulate water and carbon dioxide adsorption at the (010) surface of five olivine minerals, namely, forsterite (Mg2SiO4), calcio-olivine (Ca2SiO4), tephroite (Mn2SiO4), fayalite (Fe2SiO4), and Co-olivine (Co2SiO4). Adsorption energies per water molecule obtained from energy minimizations varied from -78 kJ mol-1 for fayalite to -128 kJ mol-1 for calcio-olivine at sub-monolayer coverage and became less exothermic as coverage increased. In contrast, carbon dioxide adsorption energies at sub-monolayer coverage ranged from -20 kJ mol-1 for fayalite to -59 kJ mol-1 for calcio-olivine. Therefore, the DFT calculations show a strong driving force for carbon dioxide displacement by water at the surface of all olivine minerals in a competitive adsorption scenario. Additionally, adsorption energies for both water and carbon dioxide were found to be more exothermic for the alkaline-earth (AE) olivines than for the transition-metal (TM) olivines and to not correlate with the solvation enthalpies of the corresponding divalent cations. However, a correlation was obtained with the charge of the surface divalent cation indicating that the more ionic character of the AE cations in the olivine structure relative to the TM cations leads to greater interactions with adsorbed water and carbon dioxide molecules at the surface and thus more exothermic adsorption energies for the AE olivines. For calcio-olivine, which exhibits the highest divalent cation charge of the five olivines, ab initio molecular dynamics simulations showed that this effect leads both water and carbon dioxide to react with the surface and form hydroxyl groups and a carbonate-like species, respectively.

Kerisit, Sebastien N.; Bylaska, Eric J.; Felmy, Andrew R.

2013-11-14

282

Carbon Dioxide Sequestration with Flue Gas Desulfurization (FGD) Gypsum  

Microsoft Academic Search

Carbonation of industrial alkaline residues can be used as a CO2 sequestration technology to reduce carbon dioxide emissions. In this study, alkaline Ca-rich flue gas desulfurization (FGD) gypsum samples were carbonated to a varying extent. These materials are cheap, available near large point sources of CO2 (power plant), and tend to react relatively rapidly with CO2 due to their chemical

Hongqi Wang; Ningning Sun; Rona J. Donahoe

2009-01-01

283

Carbonic Acid as a Reserve of Carbon Dioxide on Icy Moons: The Formation of Carbon Dioxide (CO2) in a Polar Environment  

NASA Astrophysics Data System (ADS)

Carbon dioxide (CO2) has been detected on the surface of several icy moons of Jupiter and Saturn via observation of the ?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 CO2 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 a rather surprising result pertaining to the synthesis of carbon dioxide in a polar environment. Here, carbonic acid was synthesized in a water (H2O)-carbon dioxide (CO2) (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 ?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.

Jones, Brant M.; Kaiser, Ralf I.; Strazzulla, Giovanni

2014-06-01

284

CARBON DIOXIDE CAPTURE FROM FLUE GAS USING DRY REGENERABLE SORBENTS  

SciTech Connect

The objective of this project is to develop a simple, inexpensive process to separate CO{sub 2} as an essentially pure stream from a fossil fuel combustion system using a regenerable, sodium-based sorbent. The sorbents being investigated in this project are primarily alkali carbonates, and particularly sodium carbonate and potassium carbonate, which are converted to bicarbonates, through reaction with carbon dioxide and water vapor. Bicarbonates are regenerated to carbonates when heated, producing a nearly pure CO{sub 2} stream after condensation of water vapor. This quarter, electrobalance tests conducted at LSU indicated that exposure of sorbent to water vapor prior to contact with carbonation gas does not significantly increase the reaction rate. Calcined fine mesh trona has a greater initial carbonation rate than calcined sodium bicarbonate, but appears to be more susceptible to loss of reactivity under severe calcination conditions. The Davison attrition indices for Grade 5 sodium bicarbonate, commercial grade sodium carbonate and extra fine granular potassium carbonate were, as tested, outside of the range suitable for entrained bed reactor testing. Fluidized bed testing at RTI indicated that in the initial stages of reaction potassium carbonate removed 35% of the carbon dioxide in simulated flue gas, and is reactive at higher temperatures than sodium carbonate. Removals declined to 6% when 54% of the capacity of the sorbent was exhausted. Carbonation data from electrobalance testing was correlated using a shrinking core reaction model. The activation energy of the reaction of sodium carbonate with carbon dioxide and water vapor was determined from nonisothermal thermogravimetry.

David A. Green; Brian S. Turk; Raghubir P. Gupta; William J. McMichael; Douglas P. Harrison; Ya Liang

2002-04-01

285

Helium enrichment during convective carbon dioxide dissolution  

NASA Astrophysics Data System (ADS)

Motivated by observed variations of the CO2/He ratios in natural carbon dioxide (CO2) reservoirs, such as the Bravo Dome field in northeastern New Mexico, we have performed laboratory experiments equilibrating gas mixtures containing Helium (He) and CO2 with water, at close to ambient conditions in a closed system. The experimental design allows for continuous measurement of headspace pressure as well as timed interval measurements of the CO2/He ratios and the ?13C value of CO2 in the headspace. Results from three dissolution experiments are reported: 1) pure Helium system, 2) 98% CO2 + 2% Nitrogen system, and 3) 97% CO2 and 3% Helium. Final equilibrated experimental results are compared to theoretical results obtained using Henry's Law relationships. The evolution of the amount of dissolved CO2 computed from gas pressure and gas compositions are in good agreement with Henry's Law relationships. For example, the CO2 + N2 system was initially pressurized with pure CO2 to 1323 mbar and after six days it equilibrated to a measured headspace pressure of 596 mbar. This compares very well with a calculated equilibrium headspace pressure of 592 mbar for this system. The CO2 + He system was pressurized to 1398 mbar CO2 and after six days equilibrated to a measured headspace pressure of 397 mbar. This measured pressure is slightly higher than the predicted equilibrated headspace pressure of 341 mbar, indicating a possible leak in the system during this particular experiment. In both experiments the initial pH of the water was 9.3 and the final equilibrated pH was 5.4. The ?13C value of equilibrated headspace CO2 was within 0.25 of its starting ?13C value, demonstrating insignificant carbon isotope fractionation at low pH. Measured Helium/ CO2 ratios throughout the CO2+Helium experiment preserve a non-linear trend of increasing He/ CO2 ratios through time that correlate very well with the measured pressure drop from CO2 dissolution. This indicates that gas composition, in particular the He/ CO2-ratio, can be used to infer the amount of dissolved CO2 in the field where pressure evolution is not available. Our experiments show that the rate of dissolution is determined by convective mass transfer in the brine. Convective transport is driven by the increase of water density with increasing CO2 saturation. However, unlike previous experiments with analog systems we do not observe a constant dissolution rate. This is due to the continued drop in gas pressure that continuously reduces the equilibrium aqueous CO2 concentration and with it the driving force for convection. This feed back may significantly reduce the magnitude of solubility trapping that can be expected during geological CO2 storage.

Larson, T.; Hesse, M. A.

2013-12-01

286

Comparative Assessment of Status and Opportunities for Carbon Dioxide Capture and Storage and Radioactive Waste Disposal in North America  

Microsoft Academic Search

\\u000a Aside from the target storage regions being underground, geologic carbon sequestration (GCS) and radioactive waste disposal\\u000a (RWD) share little in common in North America. The large volume of carbon dioxide (CO2) needed to be sequestered along with its relatively benign health effects present a sharp contrast to the limited volumes\\u000a and hazardous nature of high-level radioactive waste (RW). There is

Curtis M. Oldenburg; Jens T. Birkholzer

2011-01-01

287

Atmospheric carbon dioxide record from flask measurements at Lampedusa Island  

NSDL National Science Digital Library

Air samples from Lampedusa Island, located south of Sicily in the Mediterranean sea, were collected weekly from May 1992 through December 2000 and analyzed for carbon dioxide content. "On the basis of annual averages calculated from monthly averages, CO2 levels at Lampedusa Island have risen from 360.80 in 1993 to 371.27 in 2000. The data show an average trend of +1.5 ppmv/y." The data from the study, newly available this month from the Carbon Dioxide Information Analysis Center (CDIAC), include a plot of mean carbon dioxide concentration (ppmv) against time and a text table of the annual mean values. Methods, notes, and references are also provided.

Chamard, Paolo.; Ciattaglia, Luigi.; Di Sarra, Alcide.; Monteleone, Francesco.

2001-01-01

288

Carbon Dioxide Capture from Flue Gas Using Dry, Regenerable Sorbents  

SciTech Connect

This report describes research conducted between July 1, 2006 and September 30, 2006 on the use of dry regenerable sorbents for removal of carbon dioxide (CO{sub 2}) from coal combustion flue gas. Modifications to the integrated absorber/ sorbent regenerator/ sorbent cooler system were made to improve sorbent flow consistency and measurement reliability. Operation of the screw conveyor regenerator to achieve a sorbent temperature of at least 120 C at the regenerator outlet is necessary for satisfactory carbon dioxide capture efficiencies in succeeding absorption cycles. Carbon dioxide capture economics in new power plants can be improved by incorporating increased capacity boilers, efficient flue gas desulfurization systems and provisions for withdrawal of sorbent regeneration steam in the design.

David A. Green; Thomas O. Nelson; Brian S. Turk; Paul D. Box Raghubir P. Gupta

2006-09-30

289

CARBON DIOXIDE SEPARATION BY PHASE ENHANCED GAS-LIQUID ABSORPTION  

SciTech Connect

A new process called phase enhanced gas-liquid absorption has been developed in its early stage. It was found that adding another phase into the absorption system of gas/aqueous phase could enhance the absorption rate. A system with three phases was studied. In the system, gas phase was carbon dioxide. Two liquid phases were used. One was organic phase. Another was aqueous phase. By addition of organic phase into the absorption system of CO{sub 2}-aqueous phase, the absorption rate of CO{sub 2} was increased significantly. CO{sub 2} finally accumulated into aqueous phase. The experimental results proved that (1) Absorption rate of carbon dioxide was enhanced by adding organic phase into gas aqueous phase system; (2) Organic phase played the role of transportation of gas solute (CO{sub 2}). Carbon dioxide finally accumulated into aqueous phase.

Liang Hu

2004-09-30

290

CARBON DIOXIDE SEPARATION BY PHASE ENHANCED GAS-LIQUID ABSORPTION  

SciTech Connect

A new process called phase enhanced gas-liquid absorption has been developed in its early stage. It was found that adding another phase into the absorption system of gas/aqueous phase could enhance the absorption rate. A system with three phases was studied. In the system, gas phase was carbon dioxide. Two liquid phases were used. One was organic phase. Another was aqueous phase. By addition of organic phase into the absorption system of CO{sub 2}-aqueous phase, the absorption rate of CO{sub 2} was increased significantly. CO{sub 2} finally accumulated into aqueous phase. The experimental results proved that (1) Absorption rate of carbon dioxide was enhanced by adding organic phase into gas aqueous phase system; (2) Organic phase played the role of transportation of gas solute (CO{sub 2}). Carbon dioxide finally accumulated into aqueous phase.

Liang Hu; Adeyinka A. Adeyiga

2004-05-01

291

[Thoracoscopic thymectomy with carbon dioxide insufflation in the mediastinum].  

PubMed

The case is presented of a 71 year-old male, diagnosed with a thymoma. A thoracoscopic thymectomy was performed using the carbon dioxide insufflation technique in the mediastinum. During the procedure, while performing one-lung ventilation, the patient's respiration worsened. The contralateral lung had collapsed, as carbon dioxide was travelling from the mediastinum to the thorax through the opened pleura. Two-lung ventilation was decided upon, which clearly improved oxygenation in the arterial gases and airway pressures. Both pH and pCO2 stabilized. The surgical approach and the carbon dioxide technique were continued because 2-lung ventilation did not affect the surgical procedure. This technique has many serious complications and it should always be performed using 2-lung ventilation. PMID:24952826

Ferrero-Coloma, C; Navarro-Martinez, J; Bolufer, S; Rivera-Cogollos, M J; Alonso-Garca, F J; Tar-Bas, M I

2015-02-01

292

BOREAS TGB-12 Isotropic Carbon Dioxide Data over the NSA  

NASA Technical Reports Server (NTRS)

The BOREAS TGB-12 team made measurements of soil carbon inventories, carbon concentration in soil gases, and rates of soil respiration at several sites to estimate the rates of carbon accumulation and turnover in each of the major vegetation types. This data set contains information on the carbon isotopic content of carbon dioxide sampled from soils in the NSA-OBS, NSA-YJP, and NSA-OJP sites. Data were collected from 14-Nov-1993 to 10-Oct-1996. The data are stored in tabular ASCII files.

Trumbore, Susan; Hall, Forrest G. (Editor); Sundquist, Eric; Winston, Greg; Conrad, Sara K. (Editor)

2000-01-01

293

49 CFR 195.8 - Transportation of hazardous liquid or carbon dioxide in pipelines constructed with other than...  

Code of Federal Regulations, 2014 CFR

... Transportation of hazardous liquid or carbon dioxide in pipelines constructed with... Transportation of hazardous liquid or carbon dioxide in pipelines constructed with...person may transport any hazardous liquid or carbon dioxide through a pipe that is...

2014-10-01

294

Regulation of Carbonic Anhydrase Expression by Zinc, Cobalt, and Carbon Dioxide in the Marine Diatom  

E-print Network

Regulation of Carbonic Anhydrase Expression by Zinc, Cobalt, and Carbon Dioxide in the Marine of carbonic anhydrase (CA) in the marine diatom Thalassiosira weissflogii. We have examined the roles components: a mechanism for directly or indirectly taking up HCO3 and at least one carbonic anhydrase (CA

Morel, François M. M.

295

Entrapment of Carbon Dioxide in the Active Site of Carbonic Anhydrase II*  

E-print Network

Entrapment of Carbon Dioxide in the Active Site of Carbonic Anhydrase II* Received for publication step of CO2 hydration catalyzed by the zinc- metalloenzyme human carbonic anhydrase II, the binding substrates and revealing hydrophobic pockets in proteins. Since their discovery (2), the carbonic anhydrases

Gruner, Sol M.

296

Fate of fossil fuel carbon dioxide and the global carbon budget  

Microsoft Academic Search

The fate of fossil fuel carbon dioxide released into the atmosphere depends on the exchange rates of carbon between the atmosphere and three major carbon reservoirs, namely, the oceans, shallow-water sediments, and the terrestrial biosphere. Various assumptions and models used to estimate the global carbon budget for the last 20 years are reviewed and evaluated. Several versions of recent atmosphere-ocean

W. S. Broecker; T. Takahashi; H. J. Simpson; T.-H. Peng

1979-01-01

297

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

ERIC Educational Resources Information Center

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

Miyauchi, Takuya; Kamata, Masahiro

2012-01-01

298

Methanol Droplet Extinction in Carbon-Dioxide-Enriched Environments in Microgravity  

NASA Technical Reports Server (NTRS)

Diffusive extinction of methanol droplets with initial diameters between 1.25 mm and 1.72 mm, burning in a quiescent microgravity environment at one atmosphere pressure, was obtained experimentally for varying levels of ambient carbon-dioxide concentrations with a fixed oxygen concentration of 21% and a balance of nitrogen. These experiments serve as precursors to those which are beginning to be performed on the International Space Station and are motivated by the need to understand the effectiveness of carbon-dioxide as a fire suppressant in low-gravity environments. In these experiments, the flame standoff distance, droplet diameter, and flame radiation are measured as functions of time. The results show that the droplet extinction diameter depends on both the initial droplet diameter and the ambient concentration of carbon dioxide. Increasing the initial droplet diameter leads to an increased extinction diameter, while increasing the carbon-dioxide concentration leads to a slight decrease in the extinction diameter. These results are interpreted using a critical Damk hler number for extinction as predicted by an earlier theory, which is extended here to be applicable in the presence of effects of heat conduction along the droplet support fibers and of the volume occupied by the support beads

Hicks, Michael C.; Nayagam, Vedha; Williams, Forman A.

2010-01-01

299

Climate Policy Design: Interactions among Carbon Dioxide, Methane, and Urban Air Pollution Constraints  

E-print Network

Climate Policy Design: Interactions among Carbon Dioxide, Methane, and Urban Air Pollution Policy Design: Interactions among Carbon Dioxide, Methane, and Urban Air Pollution Constraints by Marcus. The third case examines the benefits of increased policy coordination between air pollution constraints

de Weck, Olivier L.

300

Carbon Dioxide Capture from Coal-Fired Power Plants: A Real Options Analysis Ram Chandra Sekar  

E-print Network

Carbon Dioxide Capture from Coal-Fired Power Plants: A Real Options Analysis by Ram Chandra Sekar;2 #12;3 Carbon Dioxide Capture in Coal-Fired Power Plants: A Real Options Analysis by Ram Chandra Sekar

301

Carbon dioxide sequestration by aqueous mineral carbonation of magnesium silicate minerals  

SciTech Connect

The dramatic increase in atmospheric carbon dioxide since the Industrial Revolution has caused concerns about global warming. Fossil-fuel-fired power plants contribute approximately one third of the total human-caused emissions of carbon dioxide. Increased efficiency of these power plants will have a large impact on carbon dioxide emissions, but additional measures will be needed to slow or stop the projected increase in the concentration of atmospheric carbon dioxide. By accelerating the naturally occurring carbonation of magnesium silicate minerals it is possible to sequester carbon dioxide in the geologically stable mineral magnesite (MgCO3). The carbonation of two classes of magnesium silicate minerals, olivine (Mg2SiO4) and serpentine (Mg3Si2O5(OH)4), was investigated in an aqueous process. The slow natural geologic process that converts both of these minerals to magnesite can be accelerated by increasing the surface area, increasing the activity of carbon dioxide in the solution, introducing imperfections into the crystal lattice by high-energy attrition grinding, and in the case of serpentine, by thermally activating the mineral by removing the chemically bound water. The effect of temperature is complex because it affects both the solubility of carbon dioxide and the rate of mineral dissolution in opposing fashions. Thus an optimum temperature for carbonation of olivine is approximately 185 degrees C and 155 degrees C for serpentine. This paper will elucidate the interaction of these variables and use kinetic studies to propose a process for the sequestration of the carbon dioxide.

Gerdemann, Stephen J.; Dahlin, David C.; O'Connor, William K.; Penner, Larry R.

2003-01-01

302

Reduction of soil carbon formation by tropospheric ozone under increased carbon dioxide levels.  

PubMed

In the Northern Hemisphere, ozone levels in the troposphere have increased by 35 per cent over the past century, with detrimental impacts on forest and agricultural productivity, even when forest productivity has been stimulated by increased carbon dioxide levels. In addition to reducing productivity, increased tropospheric ozone levels could alter terrestrial carbon cycling by lowering the quantity and quality of carbon inputs to soils. However, the influence of elevated ozone levels on soil carbon formation and decomposition are unknown. Here we examine the effects of elevated ozone levels on the formation rates of total and decay-resistant acid-insoluble soil carbon under conditions of elevated carbon dioxide levels in experimental aspen (Populus tremuloides) stands and mixed aspen-birch (Betula papyrifera) stands. With ambient concentrations of ozone and carbon dioxide both raised by 50 per cent, we find that the formation rates of total and acid-insoluble soil carbon are reduced by 50 per cent relative to the amounts entering the soil when the forests were exposed to increased carbon dioxide alone. Our results suggest that, in a world with elevated atmospheric carbon dioxide concentrations, global-scale reductions in plant productivity due to elevated ozone levels will also lower soil carbon formation rates significantly. PMID:14562100

Loya, Wendy M; Pregitzer, Kurt S; Karberg, Noah J; King, John S; Giardina, Christian P

2003-10-16

303

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

SciTech Connect

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.

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

1986-01-01

304

REDUCING THE UNCERTAINTY OF NORTH AMERICAN CARBON FLUX ESTIMATES USING AN EXTENDED ATMOSPHERIC CARBON DIOXIDE MEASUREMENT NETWORK.  

E-print Network

??We evaluate North American carbon fluxes using a monthly global Bayesian synthesis inversion that includes well-calibrated carbon dioxide concentrations measured at continental flux towers. We (more)

Butler, Martha

2010-01-01

305

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

SciTech Connect

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 make 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.

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

2006-07-08

306

Continual production of glycerol from carbon dioxide by Dunaliella tertiolecta.  

PubMed

Microalgae have high photosynthetic efficiencies and produce many valuable compounds from carbon dioxide. The Dunaliella genus accumulates glycerol, yet no commercial process currently exists for glycerol production from this microalga. Here it was found that in addition to intracellular accumulation, Dunaliella tertiolecta also releases glycerol into the external medium continuously, forming a large and stable carbon pool. The process is not affected by nutrient starvation or onset of cell death. Carbon dioxide was fixed at a constant rate, the bulk of it being channelled to extracellular glycerol (82%), resulting in enhanced photosynthetic carbon assimilation of 5 times that used for biomass production. The final extracellular glycerol concentration was 34 times the maximum concentration of intracellular glycerol; the latter declined further during cell death. Findings from this work will assist in the development of a bioconversion process to produce glycerol using D. tertiolecta without the need for cell harvest or disruption. PMID:23567730

Chow, Yvonne Y S; Goh, Serena J M; Su, Ziheng; Ng, Daphne H P; Lim, Chan Yuen; Lim, Natalie Y N; Lin, Huixin; Fang, Lei; Lee, Yuan Kun

2013-05-01

307

CARBON DIOXIDE CAPTURE FROM FLUE GAS USING DRY REGENERABLE SORBENTS  

SciTech Connect

Electrobalance studies of calcination and carbonation of sodium bicarbonate materials were conducted at Louisiana State University. Calcination in an inert atmosphere was rapid and complete at 120 C. Carbonation was temperature dependent, and both the initial rate and the extent of reaction were found to decrease as temperature was increased between 60 and 80 C. A fluidization test apparatus was constructed at RTI and two sodium bicarbonate materials were fluidized in dry nitrogen at 22 C. The bed was completely fluidized at between 9 and 11 in. of water pressure drop. Kinetic rate expression derivations and thermodynamic calculations were conducted at RTI. Based on literature data, a simple reaction rate expression, which is zero order in carbon dioxide and water, was found to provide the best fit against reciprocal temperature. Simulations based on process thermodynamics suggested that approximately 26 percent of the carbon dioxide in flue gas could be recovered using waste heat available at 240 C.

David A. Green; Brian S. Turk; Raghubir P. Gupta; Alejandro Lopez-Ortiz; Douglas P. Harrison; Ya Liang

2001-05-01

308

Heterogeneous saline formations for carbon dioxide disposal: Impact of varying heterogeneity on containment and trapping  

Microsoft Academic Search

Natural gas fields often contain carbon dioxide in their reservoir fluids. Exploitation of these resources requires the removal of carbon dioxide from produced fluids to meet quality standards for sale into a domestic market or for the processing of the gas into LNG. To limit the atmospheric emissions of carbon dioxide, a major greenhouse gas, it has been proposed that

Matthew Flett; Randal Gurton; Geoff Weir

2007-01-01

309

A correlation of optimal heat rejection pressures in transcritical carbon dioxide cycles  

E-print Network

A correlation of optimal heat rejection pressures in transcritical carbon dioxide cycles S.M. Liaoa) of transcritical carbon dioxide air-conditioning cycles. The analysis shows that the COP of the transcritical carbon dioxide cycle varies nonmonotonically with the heat rejection pressure; a maximum COP occurs

Zhao, Tianshou

310

Exergy analysis of transcritical carbon dioxide refrigeration cycle with an expander  

E-print Network

Exergy analysis of transcritical carbon dioxide refrigeration cycle with an expander Jun Lan Yang is performed for the transcritical carbon dioxide refrigeration cycles with a throttling valve compression cycle is applicable for carbon dioxide for water heating and comfort cooling and heating [4

Bahrami, Majid

311

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

Code of Federal Regulations, 2010 CFR

...2010-10-01 false Carbon dioxide alarm-T/ALL. 35.40-7 Section 35.40-7 Shipping...OPERATIONS Posting and Marking Requirements-TB/ALL. 35.40-7 Carbon dioxide alarmT/ALL. Adjacent to all carbon dioxide fire...

2010-10-01

312

Carbon Dioxide Footprint of the Northwest Power System Comments submitted by Grant County Public Utility District  

E-print Network

Carbon Dioxide Footprint of the Northwest Power System Comments submitted by Grant County Public paper: Carbon Dioxide Footprint of the Northwest Power System, dated September 13, 2007. The Grant done a very thorough job of assessing the current and future carbon dioxide footprints of the Northwest

313

Carbon dioxide fluxes over bermudagrass, native prairie, and sorghum  

Microsoft Academic Search

The Bowen ratio\\/energy balance (BREB) method was used to measure 30min water vapor and carbon dioxide (CO2) fluxes over three fields dominated by different C4 grasses (bermudagrass, tallgrass native prairie, and sorghum) at the Blackland Research Center, Temple, TX. Fluxes were related to biotic and abiotic phenomena. Carbon accumulation rates calculated from BREB measurements were compared with those determined from

W. A Dugas; M. L Heuer; H. S Mayeux

1999-01-01

314

Carbon Dioxide Capture from Flue Gas Using Dry Regenerable Sorbents  

Microsoft Academic Search

Regenerable sorbents based on sodium carbonate (NaCO) can be used to separate carbon dioxide (CO) from coal-fired power plant flue gas. Upon thermal regeneration and condensation of water vapor, CO is released in a concentrated form that is suitable for reuse or sequestration. During the research project described in this report, the technical feasibility and economic viability of a thermal-swing

Thomas Nelson; David Green; Paul Box; Raghubir Gupta; Gennar Henningsen

2007-01-01

315

Carbon Dioxide Capture from Flue Gas Using Dry, Regenerable Sorbents  

SciTech Connect

This report describes research conducted between January 1, 2006, and March 31, 2006, on the use of dry regenerable sorbents for removal of carbon dioxide (CO{sub 2}) from coal combustion flue gas. An integrated system composed of a downflow co-current contact absorber and two hollow screw conveyors (regenerator and cooler) was assembled, instrumented, debugged, and calibrated. A new batch of supported sorbent containing 15% sodium carbonate was prepared and subjected to surface area and compact bulk density determination.

David A. Green; Thomas O. Nelson; Brian S. Turk; Paul D. Box; Raghubir P. Gupta

2006-03-31

316

Insensitivity of global warming potentials to carbon dioxide emission scenarios  

Microsoft Academic Search

GLOBAL warming potentials for radiatively active trace gases (such as methane and chlorofluorocarbons) have generally been expressed1-2 relative to the time-integrated climate forcing per unit emission of carbon dioxide. Previous attempts to estimate the integrated climate forcing per unit CO2 emitted have focused on perturbations to steady-state conditions in carbon-cycle models. But for non-steady-state conditions, the integrated climate forcing from

Ken Caldeira; James F. Kasting

1993-01-01

317

Photodissociation of carbon dioxide in the Mars upper atmosphere  

NASA Technical Reports Server (NTRS)

Calculation of the intensity of two of the emissions produced during the dissociative excitation of carbon dioxide in the upper atmosphere of Mars by solar ultraviolet radiation. The calculation tangential column emission rates of the atomic oxygen 2972-A line and the carbon monoxide Cameron bands produced by the photodissociative mechanism are found to be factors of 3 and 10, respectively, smaller than the emission rates observed by Mariner ultraviolet spectrometers.

Barth, C. A.

1974-01-01

318

Potential carbon dioxide fixation by industrially important microalgae  

Microsoft Academic Search

The present study aimed at investigating the carbon metabolism in terms of carbon dioxide fixation and its destination in microalgae cultivations. To this purpose, analysis of growth parameters, media of cultivation, biomass composition and productivity and nutrients balance were performed. Four microalgae suitable for mass cultivation were evaluated: Dunaliella tertiolecta SAD-13.86, Chlorella vulgaris LEB-104, Spirulina platensis LEB-52 and Botryococcus braunii

Eduardo Bittencourt Sydney; Wilerson Sturm; Julio Cesar de Carvalho; Vanete Thomaz-Soccol; Christian Larroche; Ashok Pandey; Carlos Ricardo Soccol

2010-01-01

319

Geology of Bravo Dome carbon dioxide gas field, New Mexico  

Microsoft Academic Search

The Bravo Dome carbon dioxide gas field is located in Union and Harding Counties of northeast New Mexico. The Bravo Dome field covers approximately 800,000 acres, but areal boundaries of the field have not been fully defined. Production in 1989 was 113 bcf of gas from 272 wells. Cumulative production at the end of 1989 was 626 bcf. Estimated recoverable

1991-01-01

320

Extended-length fiber optic carbon dioxide monitoring  

NASA Astrophysics Data System (ADS)

This paper discusses the design and performance of fiber optic distributed intrinsic sensors for dissolved carbon dioxide, based on the use optical fibers fabricated so that their entire lengths are chemically sensitive. These fibers use a polymer-clad, silica-core structure where the cladding undergoes a large, reversible, change in optical absorbance in the presence of CO2. The local "cladding loss" induced by this change is thus a direct indication of the carbon dioxide concentration in any section of the fiber. To create these fibers, have developed a carbon dioxide-permeable polymer material that adheres well to glass, is physically robust, has a refractive index lower than fused silica, and acts as excellent hosts for a unique colorimetric indicator system that respond to CO2. We have used this proprietary material to produce carbon-dioxide sensitive fibers up to 50 meters long, using commercial optical fiber fabrication techniques. The sensors have shown a measurement range of dissolved CO2 of 0 to 1,450 mg/l (0 to 100% CO2 saturation), limit of detection of 0.3 mg/l and precision of 1.0 mg/l in the 0 to 50 mg/l dissolved CO2 range, when a 5 meter-long sensor fiber segment is used. Maximum fiber length, minimum detectable concentration, and spatial resolution can be adjusted by adjusting indicator concentration and fiber design.

Delgado-Alonso, Jesus; Lieberman, Robert A.

2013-05-01

321

Molecular simulations of carbon dioxide and water: cation solvation.  

PubMed

Proposed carbon dioxide sequestration scenarios in sedimentary reservoirs require investigation into the interactions between supercritical carbon dioxide, brines, and the mineral phases found in the basin and overlying caprock. Molecular simulations can help to understand the partitioning of metal cations between aqueous solutions and supercritical carbon dioxide where limited experimental data exist. In this effort, we used classical molecular dynamics simulations to compare the solvation of alkali and alkaline-earth metal cations in water and liquid CO(2) at 300 K by combining a flexible simple point charge model for water and an accurate flexible force field for CO(2). Solvation energies for these cations are larger in water than in carbon dioxide, suggesting that they will partition preferentially into water. In both aqueous and CO(2) solutions, the solvation energies decrease with cation size and increase with cation charge. However, changes in solvation energy with ionic radii are smaller in CO(2) than in water suggesting that the partitioning of cations into CO(2) will increase with ion size. Simulations of the interface between aqueous solution and supercritical CO(2) support this suggestion in that some large cations (e.g., Cs(+) and K(+)) partition into the CO(2) phase, often with a partial solvation sphere of water molecules. PMID:22779448

Criscenti, Louise J; Cygan, Randall T

2013-01-01

322

Counter-current carbon dioxide extraction of soy skim  

Technology Transfer Automated Retrieval System (TEKTRAN)

The use of carbon dioxide in a counter-current fractionation column was investigated as a means to remove residual fat from soy skim after enzyme-assisted aqueous extraction of soybeans. The stainless steel column was 1.2 meters long with an internal diameter of 1.75 cm and filled protruded stainles...

323

The Subsurface Fluid Mechanics of Geologic Carbon Dioxide Storage  

E-print Network

The Subsurface Fluid Mechanics of Geologic Carbon Dioxide Storage by Michael Lawrence Szulczewski S the fluid mechanics of CO2 storage, with the goal of informing two practical questions. The first question by . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Heidi M. Nepf Chair, Departmental Committee for Graduate Students #12;2 #12;The Subsurface Fluid

324

Carbon Dioxide Production and Sodium Transport by the Toad Bladder  

Microsoft Academic Search

IN order to investigate further the relationship of cellular metabolism to active ion transport, we have correlated carbon dioxide production with sodium transport by the urinary bladder of the toad, Bufo marinus, in vitro. The toad bladder was mounted so as to separate the two halves of a glass chamber, and each side was bathed with a phosphate Ringer's solution

Roy H. Maffly; Cecil H. Coggins

1965-01-01

325

Climate change and carbon dioxide storage Herbert E. Huppert  

E-print Network

1 Climate change and carbon dioxide storage Herbert E. Huppert Institute of Theoretical, spread material in a roughly symmetric fashion. Particulate matter, or planetesmials, came on Earth having been found in Australia. Of course the Earth has changed dramatically over these four

Huppert, Herbert

326

Carbon dioxide rapid superpulsed laser treatment of erythroplasia of Queyrat.  

PubMed

A single case of erythroplasia of Queyrat successfully treated by rapid superpulsed carbon dioxide laser emission is presented. The results of this single case and previous studies are compared with thos obtained by different modalities used in the past. PMID:6773202

Rosemberg, S K; Fuller, T A

1980-08-01

327

The Concentration of Atmospheric Carbon Dioxide in Hawaii  

Microsoft Academic Search

The concentration of atmospheric carbon dioxide at and near Mauna Loa Ob- servatory, Hawaii, is reported for the first six years (1958-1963) of a long-term program to document the effects of the combustion of coal and petroleum on the distribution of COs gas in the atmosphere and in the world's oceans. The majority of the measurements reported here were obtained

Jack C. Pales; Charles D. Keeling

1965-01-01

328

Global Warming: Carbon Dioxide and the Greenhouse Effect  

NSDL National Science Digital Library

This video segment demonstrates carbon dioxide's role in the greenhouse effect and explains how increasing concentrations of C02 in the atmosphere may be contributing to global warming. Video includes an unusual demonstration of C02's heat-absorbing properties, using infrared film, a researcher's face, and a stream of C02 between them.

FRONTLINE/NOVA

329

The role of carbon dioxide in ammonia emission from manure  

Technology Transfer Automated Retrieval System (TEKTRAN)

Ammonia emission from manure is a significant loss of fixed N from agricultural systems, and contributes to air pollution and ecosystem degradation. Despite the development of numerous mathematical models for predicting ammonia emission, the interactions between carbon dioxide emission, manure pH, a...

330

Carbon dioxide supersaturation in the surface waters of lakes  

Microsoft Academic Search

Data on the partial pressure of carbon dioxide (CO) in the surface waters from a large number of lakes (1835) with a worldwide distribution show that only a small proportion of the 4665 samples analyzed (less than 10 percent) were within {+-}20 percent of equilibrium with the atmosphere and that most samples (87 percent) were supersaturated. The mean partial pressure

J. J. Cole; N. F. Caraco; G. W. Kling; T. K. Kratz

1994-01-01

331

Using the 5E Learning Cycle Sequence with Carbon Dioxide  

ERIC Educational Resources Information Center

The authors used the 5E learning cycle (engage, explore, explain, extend, and evaluate) and a pulmonary carbon dioxide mystery to introduce eighth grade students to the study of chemistry. The activity engages students in measurement, data collection, data analysis, media and internet research, research design, and report writing as they search

Schlenker, Richard M.; Blanke, Regina; Mecca, Peter

2007-01-01

332

40 CFR 86.1524 - Carbon dioxide analyzer calibration.  

Code of Federal Regulations, 2012 CFR

...Petroleum Gas-Fueled Diesel-Cycle Heavy-Duty Engines, New Otto-Cycle Light-Duty Trucks, and New...Petroleum Gas-Fueled Diesel-Cycle Light-Duty Trucks; Idle Test Procedures 86.1524 Carbon dioxide analyzer...

2012-07-01

333

40 CFR 86.1524 - Carbon dioxide analyzer calibration.  

Code of Federal Regulations, 2010 CFR

...Petroleum Gas-Fueled Diesel-Cycle Heavy-Duty Engines, New Otto-Cycle Light-Duty Trucks, and New...Petroleum Gas-Fueled Diesel-Cycle Light-Duty Trucks; Idle Test Procedures 86.1524 Carbon dioxide analyzer...

2010-07-01

334

40 CFR 86.1524 - Carbon dioxide analyzer calibration.  

Code of Federal Regulations, 2013 CFR

...Petroleum Gas-Fueled Diesel-Cycle Heavy-Duty Engines, New Otto-Cycle Light-Duty Trucks, and New...Petroleum Gas-Fueled Diesel-Cycle Light-Duty Trucks; Idle Test Procedures 86.1524 Carbon dioxide analyzer...

2013-07-01

335

40 CFR 86.1524 - Carbon dioxide analyzer calibration.  

Code of Federal Regulations, 2011 CFR

...Petroleum Gas-Fueled Diesel-Cycle Heavy-Duty Engines, New Otto-Cycle Light-Duty Trucks, and New...Petroleum Gas-Fueled Diesel-Cycle Light-Duty Trucks; Idle Test Procedures 86.1524 Carbon dioxide analyzer...

2011-07-01

336

40 CFR 86.1524 - Carbon dioxide analyzer calibration.  

Code of Federal Regulations, 2014 CFR

...Petroleum Gas-Fueled Diesel-Cycle Heavy-Duty Engines, New Otto-Cycle Light-Duty Trucks, and New...Petroleum Gas-Fueled Diesel-Cycle Light-Duty Trucks; Idle Test Procedures 86.1524 Carbon dioxide analyzer...

2014-07-01

337

Carbon dioxide flash-freezing applied to ice cream production  

E-print Network

(cont.) Carbon dioxide is recompressed from 1.97 x 106 Pa (285 psi) to 3.96 x 106 Pa (575 psi). The process is scaled by increasing the number of nozzles to accommodate the desired flow rate. Only 165 nozzles are required ...

Peters, Teresa Baker, 1981-

2006-01-01

338

27 CFR 24.319 - Carbon dioxide record.  

Code of Federal Regulations, 2013 CFR

A proprietor who uses carbon dioxide in still wine shall maintain a record of the laboratory tests conducted to establish compliance with the limitations prescribed in 24.245. (Sec. 201, Pub. L. 85-859, 72 Stat. 1381, as amended (26 U.S.C....

2013-04-01

339

46 CFR 196.37-9 - Carbon dioxide alarm.  

Code of Federal Regulations, 2010 CFR

46 ? Shipping ? 7 ? 2010-10-01 ? 2010-10-01 ? false ? Carbon dioxide alarm. ? 196.37-9 ? Section 196.37-9 ? Shipping ? COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) ? OCEANOGRAPHIC RESEARCH VESSELS ? OPERATIONS ? Markings for Fire and Emergency Equipment, etc. ? 196.37-9 ?...

2010-10-01

340

46 CFR 196.37-9 - Carbon dioxide alarm.  

Code of Federal Regulations, 2011 CFR

46 ? Shipping ? 7 ? 2011-10-01 ? 2011-10-01 ? false ? Carbon dioxide alarm. ? 196.37-9 ? Section 196.37-9 ? Shipping ? COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) ? OCEANOGRAPHIC RESEARCH VESSELS ? OPERATIONS ? Markings for Fire and Emergency Equipment, etc. ? 196.37-9 ?...

2011-10-01

341

40 CFR 86.224-94 - Carbon dioxide analyzer calibration.  

Code of Federal Regulations, 2012 CFR

Emission Regulations for 1994 and Later Model Year Gasoline-Fueled New Light-Duty Vehicles, New Light-Duty Trucks and New Medium-Duty Passenger Vehicles; Cold Temperature Test Procedures 86.224-94 Carbon dioxide analyzer calibration. The provisions of ...

2012-07-01

342

Modeling Seasonality in Carbon Dioxide Emissions From Fossil Fuel Consumption  

Microsoft Academic Search

Using United States data, a method is developed to estimate the monthly consumption of solid, liquid and gaseous fossil fuels using monthly sales data to estimate the relative monthly proportions of the total annual national fossil fuel use. These proportions are then used to estimate the total monthly carbon dioxide emissions for each state. From these data, the goal is

P. Kishore; K. Igarashi; H. Oikawa; M. Uotome; J. S. Gregg; R. J. Andres

2004-01-01

343

Corrosion of various engineering alloys in supercritical carbon dioxide  

E-print Network

The corrosion resistance of ten engineering alloys were tested in a supercritical carbon dioxide (S-CO 2) environment for up to 3000 hours at 610C and 20MPa. The purpose of this work was to evaluate each alloy as a potential ...

Gibbs, Jonathan Paul

2010-01-01

344

Treatment of chronic lip fissures with carbon dioxide laser  

Microsoft Academic Search

Resurfacing of cutaneous tissue with carbon dioxide laser increases the amount and quality of collagen and elastin subepithelially. We used this technique to ablate 12 chronic lip fissures in one woman and 10 men. Five patients fissures had persisted for durations ranging from several months to seven years; the other six had fissures that split between one and five times

James Combes; Timothy K. Mellor

2009-01-01

345

Elevated Carbon Dioxide and Ozone Concentrations Alter Soybean Antioxidant Metabolism  

Technology Transfer Automated Retrieval System (TEKTRAN)

One important mechanism by which plants sense and respond to their environment is through redox control. Oxidative damage at the cellular level can feed forward to decrease leaf photosynthesis and therefore canopy and ecosystem productivity. How rising atmospheric carbon dioxide (CO2) and tropospher...

346

How Can We Use Carbon Dioxide as a Solvent?  

ERIC Educational Resources Information Center

This article describes the work being undertaken to make more use of supercritical carbon dioxide as a green solvent. It discusses how the use of surfactants can address the limitations of supercritical CO[subscript 2] in dissolving solutes that are polar and of higher molecular weight. The design of appropriate hydrocarbon CO[subscript 2]-philic

Mohamed, Azmi; Eastoe, Julian

2011-01-01

347

Classroom Carbon Dioxide Concentration, School Attendance, and Educational Attainment  

ERIC Educational Resources Information Center

Background: We tested the hypothesis that classroom carbon dioxide (CO[subscript 2]) concentration is inversely related to child school attendance and educational attainment. Methods: Concentrations of CO[subscript 2] were measured over a 3-5?day period in 60 naturally ventilated classrooms of primary school children in Scotland. Concentrations of

Gaihre, Santosh; Semple, Sean; Miller, Janice; Fielding, Shona; Turner, Steve

2014-01-01

348

Environmental Challenges: Radon and Carbon Dioxide in School Buildings.  

ERIC Educational Resources Information Center

Many school buildings with high radon levels also exhibit high carbon dioxide levels that starve the minds of students for oxygen. Administrators must realize that the world's best educator cannot teach minds made dysfunctional by their environment. This article describes Environmental Protection Agency testing results and offers radon monitoring

Krueger, James

1991-01-01

349

Biodiversity and biological impact of ocean disposal of carbon dioxide  

SciTech Connect

Five major characteristics of deep-sea organisms that are relevant to the carbon dioxide ocean sequestration are pointed out. They are (1) low biological activities, (2) long life span, (3) high sensitivity to the environmental disturbance, (4) high species diversity, and (5) low density. These characteristics suggest the deep-sea species are sensitive to the environmental disturbance, and once they are damaged, they may easily become extinct or it might take a long time to recover. To get public acceptance for ocean sequestration of carbon dioxide, the authors need a reliable assessment of its affects on the deep-sea ecosystem based on an accurate model. For a better modeling, data regarding the long-term (chronic) effect of slightly increased concentration of carbon dioxide on the deep-sea organisms are prerequisite. Precise data regarding such biological characteristics can be obtained only from in-situ experiments. To develop a system for ecophysiological in-situ experiments of deep-sea organisms is thus as important as solving the technological problems related to the ocean sequestration of carbon dioxide.

Shirayama, Yoshihisa [Univ. of Tokyo (Japan)] [Univ. of Tokyo (Japan)

1998-07-01

350

2008 Nature Publishing Group Atmospheric carbon dioxide linked  

E-print Network

.29 The relationship between atmospheric carbon dioxide (CO2) and climate in the Quaternary period has been extensively . The range of geological evidence for cool periods during the high CO2 Mesozoic `greenhouse world'2,3 of high and theoretical modelling6,7 . These records indicate that atmospheric CO2 rose from 420 p.p.m.v. in the Triassic

Cai, Long

351

Carbon dioxide fixation by microalgae cultivated in open bioreactors  

Microsoft Academic Search

The biofixation of carbon dioxide (CO2) by microalgae has been proven to be an efficient and economical method, mainly due to the photosynthetic ability of these microorganisms to use this gas as a source of nutrients for their development. The aim of this work was to study the growth of Spirulina LEB18 and Chlorella kessleri microalgae, exposed to controlled and

Ana Priscila Centeno da Rosa; Lisiane Fernandes Carvalho; Luzia Goldbeck; Jorge Alberto Vieira Costa

2011-01-01

352

SELECTIVE OXIDATION IN SUPERCRITICAL CARBON DIOXIDE USING CLEAN OXIDANTS  

EPA Science Inventory

We have systematically investigated heterogeneous catalytic oxidation of different substrates in supercritical carbon dioxide (SC-CO2). Three types of catagysts: a metal complex, 0.5% platinum g-alumina and 0.5% palladium g-alumina were used at a pressure of 200 bar, temperatures...

353

Household carbon dioxide production in relation to the greenhouse effect  

Microsoft Academic Search

A survey of 655 households from eastern suburbs of Melbourne was undertaken to determine householders[prime] attitudes to, and understanding of, the greenhouse effect. Carbon dioxide emissions resulting from car, electricity and gas use were computed and household actions which could reduce CO[sub 2] emissions were addressed. Preliminary analysis of the results indicates that householders in this area are aware of,

D. Stokes; A. Lindsay; J. Marinopoulos; A. Treloar; G. Wescott

1994-01-01

354

Raising the Level of Carbon Dioxide in Your Blood  

NSDL National Science Digital Library

In this activity (on page 146 of the PDF), learners will explore the effects of increased carbon dioxide in the bloodstream. This activity can be enhanced by sharing the "Astronaut's Sleep" Podcast with learners (see related resource link). This resource guide includes background information and sample evaluation questions. Note: learners with respiratory ailments should not participate as subjects.

Marlene Y. MacLeish

2013-05-15

355

High-resolution mapping of motor vehicle carbon dioxide emissions  

NASA Astrophysics Data System (ADS)

fuel-based inventory for vehicle emissions is presented for carbon dioxide (CO2) and mapped at various spatial resolutions (10 km, 4 km, 1 km, and 500 m) using fuel sales and traffic count data. The mapping is done separately for gasoline-powered vehicles and heavy-duty diesel trucks. Emission estimates from this study are compared with the Emissions Database for Global Atmospheric Research (EDGAR) and VULCAN. All three inventories agree at the national level within 5%. EDGAR uses road density as a surrogate to apportion vehicle emissions, which leads to 20-80% overestimates of on-road CO2 emissions in the largest U.S. cities. High-resolution emission maps are presented for Los Angeles, New York City, San Francisco-San Jose, Houston, and Dallas-Fort Worth. Sharp emission gradients that exist near major highways are not apparent when emissions are mapped at 10 km resolution. High CO2 emission fluxes over highways become apparent at grid resolutions of 1 km and finer. Temporal variations in vehicle emissions are characterized using extensive day- and time-specific traffic count data and are described over diurnal, day of week, and seasonal time scales. Clear differences are observed when comparing light- and heavy-duty vehicle traffic patterns and comparing urban and rural areas. Decadal emission trends were analyzed from 2000 to 2007 when traffic volumes were increasing and a more recent period (2007-2010) when traffic volumes declined due to recession. We found large nonuniform changes in on-road CO2 emissions over a period of ~5 years, highlighting the importance of timely updates to motor vehicle emission inventories.

McDonald, Brian C.; McBride, Zoe C.; Martin, Elliot W.; Harley, Robert A.

2014-05-01

356

Tracing Changes in Ecosystem Function under Elevated Carbon Dioxide Conditions  

NSDL National Science Digital Library

This peer-reviewed article from BioScience journal is on the effects of elevated carbon dioxide on the ecosystem. Responses of ecosystems to elevated levels of atmospheric carbon dioxide (CO2) remain a critical uncertainty in global change research. Two key unknown factors are the fate of carbon newly incorporated by photosynthesis into various pools within the ecosystem and the extent to which elevated CO2 is transferred to and sequestered in pools with long turnover times. The CO2 used for enrichment in many experiments incorporates a dual isotopic tracer, in the sense that ratios of both the stable carbon-13 (13C) and the radioactive carbon-14 (14C) isotopes with respect to carbon-12 are different from the corresponding ratios in atmospheric CO2. Here we review techniques for using 13C and 14C abundances to follow the fate of newly fixed carbon and to further our understanding of the turnover times of ecosystem carbon pools. We also discuss the application of nitrogen, oxygen, and hydrogen isotope analyses for tracing changes in the linkages between carbon, nitrogen, and water cycles under conditions of elevated CO2.

DIANE E. PATAKI, DAVID S. ELLSWORTH, R. DAVE EVANS, MIQUEL GONZALEZ-MELER, JOHN KING, STEVEN W. LEAVITT, GUANGHUI LIN, ROSER MATAMALA, ELISE PENDALL, ROLF SIEGWOLF, CHRIS VAN KESSEL, and JAMES R. EHLERINGER (;)

2003-09-01

357

Supercritical carbon dioxide cycle control analysis.  

SciTech Connect

This report documents work carried out during FY 2008 on further investigation of control strategies for supercritical carbon dioxide (S-CO{sub 2}) Brayton cycle energy converters. The main focus of the present work has been on investigation of the S-CO{sub 2} cycle control and behavior under conditions not covered by previous work. An important scenario which has not been previously calculated involves cycle operation for a Sodium-Cooled Fast Reactor (SFR) following a reactor scram event and the transition to the primary coolant natural circulation and decay heat removal. The Argonne National Laboratory (ANL) Plant Dynamics Code has been applied to investigate the dynamic behavior of the 96 MWe (250 MWt) Advanced Burner Test Reactor (ABTR) S-CO{sub 2} Brayton cycle following scram. The timescale for the primary sodium flowrate to coast down and the transition to natural circulation to occur was calculated with the SAS4A/SASSYS-1 computer code and found to be about 400 seconds. It is assumed that after this time, decay heat is removed by the normal ABTR shutdown heat removal system incorporating a dedicated shutdown heat removal S-CO{sub 2} pump and cooler. The ANL Plant Dynamics Code configured for the Small Secure Transportable Autonomous Reactor (SSTAR) Lead-Cooled Fast Reactor (LFR) was utilized to model the S-CO{sub 2} Brayton cycle with a decaying liquid metal coolant flow to the Pb-to-CO{sub 2} heat exchangers and temperatures reflecting the decaying core power and heat removal by the cycle. The results obtained in this manner are approximate but indicative of the cycle transient performance. The ANL Plant Dynamics Code calculations show that the S-CO{sub 2} cycle can operate for about 400 seconds following the reactor scram driven by the thermal energy stored in the reactor structures and coolant such that heat removal from the reactor exceeds the decay heat generation. Based on the results, requirements for the shutdown heat removal system may be defined. In particular, the peak heat removal capacity of the shutdown heat removal loop may be specified to be 1.1 % of the nominal reactor power. An investigation of the oscillating cycle behavior calculated by the ANL Plant Dynamics Code under specific conditions has been carried out. It has been found that the calculation of unstable operation of the cycle during power reduction to 0 % may be attributed to the modeling of main compressor operation. The most probable reason for such instabilities is the limit of applicability of the currently used one-dimensional compressor performance subroutines which are based on empirical loss coefficients. A development of more detailed compressor design and performance models is required and is recommended for future work in order to better investigate and possibly eliminate the calculated instabilities. Also, as part of such model development, more reliable surge criteria should be developed for compressor operation close to the critical point. It is expected that more detailed compressor models will be developed as a part of validation of the Plant Dynamics Code through model comparison with the experiment data generated in the small S-CO{sub 2} loops being constructed at Barber-Nichols Inc. and Sandia National Laboratories (SNL). Although such a comparison activity had been planned to be initiated in FY 2008, data from the SNL compression loop currently in operation at Barber Nichols Inc. has not yet become available by the due date of this report. To enable the transient S-CO{sub 2} cycle investigations to be carried out, the ANL Plant Dynamics Code for the S-CO{sub 2} Brayton cycle was further developed and improved. The improvements include further optimization and tuning of the control mechanisms as well as an adaptation of the code for reactor systems other than the Lead-Cooled Fast Reactor (LFR). Since the focus of the ANL work on S-CO{sub 2} cycle development for the majority of the current year has been on the applicability of the cycle to SFRs, work has started on modification of the ANL Plant Dynamics Code to allow

Moisseytsev, A.; Sienicki, J. J. (Nuclear Engineering Division)

2011-04-11

358

Tropical deforestation and atmospheric carbon dioxide  

Microsoft Academic Search

Recent estimates of the net release of carbon to the atmosphere from deforestation in the tropics have ranged between 0.4 and 2.5 1015 g yr-1. Two things have happened to require a revision of these estimates. First, refinements of the methods used to estimate the stocks of carbon in the vegetation of tropical forests have produced new estimates that

R. A. Houghton

1991-01-01

359

Application of carbon nanotube in wireless sensor network to monitor carbon dioxide  

Microsoft Academic Search

Carbon nanotubes (CNTs) are allotropes of carbon with a cylindrical nanostructure. Over the years, new discoveries have led to new applications, often taking advantage of their unique electrical properties, extraordinary strength and efficiency in heat conduction. Since industrialisation, human activities have resulted in steadily increasing concentrations of the greenhouse gases. Excess amount of carbon dioxide (CO2) in living environment is

Othman Sidek; S. A. Quadri; Shahid Kabir; Muhammad Hassan Bin Afzal

2012-01-01

360

A 400 million year carbon isotope record of pedogenic carbonate: Implications for paleoatmospheric carbon dioxide  

SciTech Connect

A 400 record of atmospheric carbon dioxide levels has been estimated by applying a CO{sub 2} paleobarometer to a database of 758 analyses of paleosol (fossil soil) carbonates. This database is a compilation of new data and previously published values from the literature. Many new analyses of Mesozoic paleosols are reported, an era poorly represented in the literature. Results indicate that large fluctuations in atmospheric carbon dioxide levels have occurred over the study interval, ranging from the current level up to ten times the current level. Declining pCO{sub 2} levels through the middle Paleozoic culminate in low levels in the Early Permian. An abrupt increase in pCO{sub 2} in the Early Permian is followed by a decrease prior to the Permo-Triassic boundary. Carbon dioxide levels increase through the Triassic to approx. 3,000 ppmV, a level maintained through the Jurassic period. Levels lowered through the Cretaceous, dropping to less than 1,000 ppmV prior to the Cretaceous-Tertiary boundary. Relatively low levels persisted throughout the Cenozoic, with some evidence of higher levels in the Eocene and Oligocene.

Ekart, D.D.; Cerling, T.E.; Montanez, I.P.; Tabor, N.J.

1999-12-01

361

Satellite-based measurements of surface deformation reveal fluid flow associated with the geological storage of carbon dioxide  

SciTech Connect

Interferometric Synthetic Aperture Radar (InSAR), gathered over the In Salah CO{sub 2} storage project in Algeria, provides an early indication that satellite-based geodetic methods can be effective in monitoring the geological storage of carbon dioxide. An injected volume of 3 million tons of carbon dioxide, from one of the first large-scale carbon sequestration efforts, produces a measurable surface displacement of approximately 5 mm/year. Using geophysical inverse techniques we are able to infer flow within the reservoir layer and within a seismically detected fracture/ fault zone intersecting the reservoir. We find that, if we use the best available elastic Earth model, the fluid flow need only occur in the vicinity of the reservoir layer. However, flow associated with the injection of the carbon dioxide does appear to extend several kilometers laterally within the reservoir, following the fracture/fault zone.

Vasco, D.W.; Rucci, A.; Ferretti, A.; Novali, F.; Bissell, R.; Ringrose, P.; Mathieson, A.; Wright, I.

2009-10-15

362

Chalcogen-bonded complexes of some carbon dioxide analogues  

NASA Astrophysics Data System (ADS)

Ab initio calculations have been carried out on the sulphur-bonded van der Waals complexes formed between the carbon dioxide analogues carbonyl sulphide, carbon disulphide and thiocarbonyl selenide, and the common electron donors ammonia, water, phosphine and hydrogen sulphide. The structures of these twelve complexes are all similar, and involve an approximately linear XCS⋯Y fragment (X = O, S, Se; Y = N, O, P, S). These structures contrast with those of the oxygen-bound complexes of carbon dioxide, carbonyl sulphide and carbonyl selenide reported earlier which, with the exception of the hydrogen sulphide species, are characterized by four-membered rings with varying orientations involving the C, O, H and Y atoms. The molecular structures, interaction energies and vibrational spectra have been studied, and the variations in these properties have been correlated with the complex structures and with the molecular quadrupole moments of the acid monomers.

Ramasami, Ponnadurai; Ford, Thomas A.

2014-08-01

363

Carbon dioxide enrichment of greenhouse crops  

SciTech Connect

These volumes bring current information to growers, plant scientists, horticulturalists, and extension officers on the influence of atmospheric CO2 on greenhouse crops. Results of recent research and successful techniques in the US and Europe are reported. Discussions cover such practical topics as fossil and biological sources of CO2, control, strategies of choosing optimal concentration, effects of outdoor climate, and economic factors. Volume II will follow.

Enoch, H.Z.; Kimball, B.A. (eds.)

1986-01-01

364

Geochemical consequences of increased atmospheric carbon dioxide on coral reefs  

USGS Publications Warehouse

A coral reef represents the net accumulation of calcium carbonate (CaCO3) produced by corals and other calcifying organisms. If calcification declines, then reef-building capacity also declines. Coral reef calcification depends on the saturation state of the carbonate mineral aragonite of surface waters. By the middle of the next century, an increased concentration of carbon dioxide will decrease the aragonite saturation state in the tropics by 30 percent and biogenic aragonite precipitation by 14 to 30 percent. Coral reefs are particularly threatened, because reef-building organisms secrete metastable forms of CaCO3, but the biogeochemical consequences on other calcifying marine ecosystems may be equally severe.

Kleypas, J.A.; Buddemeier, R.W.; Archer, D.; Gattuso, J.-P.; Langdon, C.; Opdyke, B.N.

1999-01-01

365

Vapor-liquid equilibria of binary mixtures containing methane, ethane, and carbon dioxide from molecular simulation  

NASA Astrophysics Data System (ADS)

The NpT + test particle method is used in order to predict vapor-liquid equilibria of the mixtures methane + ethane, methane + carbon dioxide, and carbon dioxide +ethane by molecular simulations. The pure-component molecular models were fitted to the experimental vapor pressures and saturated liquid densities in previous papers, which used the same simulation method for the determination of the phase equilibria. For each binary mixture the two unlike interaction parameters were determined from one experimental excess volume and one excess enthalpy. Based on these molecular models the vapor-liquid phase equilibria were calculated for each mixture at three temperatures. Comparison of the pressure-composition data with experimental results shows the high predictive power of this molecular based procedure. This statement is confirmed by additional comparisons of the pressure-composition diagrams and the pressure-density diagrams with results from equations of state.

Vrabec, J.; Fischer, J.

1996-07-01

366

The use of seawater as a carbon dioxide scrubbing medium for underwater life support  

SciTech Connect

Experimental evidence suggests that seawater could be used to scrub carbon dioxide form cabin air in underwater habitats. Seawater has the capacity to absorb carbon dioxide in quantities directly dependent on a number of variables, the most significant of which is the partial pressure of the carbon dioxide in the gas. The absorption capacities of freshwater and seawater are determined in this study in relation to the variables of carbon dioxide partial pressure, water temperature and pH for use in simple engineering design calculations. A conceptual carbon dioxide scrubber is proposed which involves the direct absorption of carbon dioxide in small concentrations in diffused air by a pressurized seawater tower. This conceptual design can potentially offer a low-energy seawater carbon dioxide scrubber to be externally or internally mounted on an underwater habitat.

Nuckols, M.L. [Naval Academy, Annapolis, MD (United States). Dept. of Naval Architecture, Ocean and Marine Engineering

1996-09-01

367

PMEL CO2: Carbon Dioxide Program  

NSDL National Science Digital Library

In order to advance a shared scientific understanding of the ocean's carbon cycle and how it continues to change over time, the National Oceanic and Atmospheric Administration (NOAA) continues to investigate the evolving state of the ocean carbon chemistry with high quality measurements on ships and autonomous platforms. This website provides information on their public outreach efforts, along with news features on how these changes may affect everything from marine animal populations to tourism operations. On the homepage, visitors should check out the "Map & Data Viewer", which allows them to look at the collected carbon data via a 3D projection. The site also contains a "Data Portal" which allows interested parties to examine the data that has been collected thus far, along with historical data sets. The site is rounded out by sections that cover their ongoing research projects and their current observations on these changes.

368

Carbon dioxide clouds in an early dense Martian atmosphere  

NASA Astrophysics Data System (ADS)

We use a time-dependent, microphysical cloud model to study the formation of carbon dioxide clouds in the Martian atmosphere. Laboratory studies by Glandorf et al. [2002] show that high critical supersaturations are required for CO2 cloud particle nucleation and that surface kinetic growth is not limited. These conditions, which are similar to those for cirrus clouds on Earth, lead to the formation of carbon dioxide ice particles with radii greater than 500 ?m and concentrations less than 0.1 cm-3 for typical atmospheric conditions. Within the current Martian atmosphere, CO2 cloud formation is possible at the poles during winter and possibly at high altitudes in the tropics. In both cases, temperature perturbations of several degrees below the CO2 saturation temperature are required to nucleate new cloud particles, suggesting that dynamical processes are the most common initiators of carbon dioxide clouds rather than diabatic cooling. The microphysical cloud model, coupled to a two-stream radiative transfer model, is used to reexamine the impact of CO2 clouds on the surface temperature within a dense CO2 atmosphere. The formation of carbon dioxide clouds leads to a warmer surface than what would be expected for clear sky conditions, but it also warms the atmosphere. The amount of surface warming is sensitive to the presence of dust and water vapor in the atmosphere, both of which act to dampen cloud effects. The radiative warming of the atmosphere associated with cloud formation, as well as latent heating, work to dissipate the clouds when present. In these simulations, clouds never last for periods much longer than several days, limiting their overall effectiveness for warming the surface. The time average cloud optical depth is approximately unity leading to a 5-10 K surface warming, depending on the surface pressure. The surface temperature does not rise above the freezing point of liquid water even for pressures as high as 5 bars, at a solar luminosity of 75% the current value. Our model shows that warming of the surface-atmosphere system by carbon dioxide clouds is self-limiting, since by heating the air the clouds cause themselves to dissipate. However, further analysis of the climatic effects of carbon dioxide clouds considering their global distribution and properties is warranted.

Colaprete, Anthony; Toon, Owen B.

2003-04-01

369

Carbon dioxide clouds in an early dense Martian atmosphere  

NASA Astrophysics Data System (ADS)

We use a time dependent, microphysical cloud model to study the formation of carbon dioxide clouds in the Martian atmosphere. Laboratory studies by Glandorf et al. (2002) show that high critical supersaturations are required for cloud particle nucleation and that surface kinetic growth is not limited. These conditions, which are similar to those for cirrus clouds on Earth, lead to the formation of carbon dioxide ice particles with radii greater than 500 ?m and concentrations less than 0.1 cm-3 for typical atmospheric conditions. Within the current Martian atmosphere, CO2 cloud formation is possible at the poles during winter and possibly at high altitudes in the tropics. In both cases, temperature perturbations of several degrees below the CO2 saturation temperature are required to nucleate new cloud particles suggesting that dynamical processes are the most common initiators of carbon dioxide clouds rather than diabatic cooling. The microphysical cloud model, coupled to a two-stream radiative transfer model, is used to reexamine the impact of CO2 clouds on the surface temperature within a dense CO2 atmosphere. The formation of carbon dioxide clouds leads to a warmer surface than what would be expected for clear sky conditions, but it also warms the atmosphere. The amount of surface warming is sensitive to the presence of dust and water vapor in the atmosphere, both of which act to dampen cloud effects. The radiative warming of the atmosphere associated with cloud formation, as well as latent heating, work to dissipate the clouds when present. In these simulations, clouds never last for periods much longer than several days, limiting their overall effectiveness for warming the surface. The time average cloud optical depth is approximately unity leading to a 5 - 10 K surface warming, depending on the surface pressure. The surface temperature does not rise above the freezing point of liquid water even for pressures as high as 5 bars, at a solar luminosity of 75% the current value. Our model shows that warming of the surface-atmosphere system by carbon dioxide clouds is self-limiting, since by heating the air the clouds cause themselves to dissipate. However, further analysis of the climatic effects of carbon dioxide clouds considering their global distribution and properties is warranted.

Colaprete, A.; Toon, O. B.

2002-12-01

370

Potential carbon dioxide fixation by industrially important microalgae.  

PubMed

The present study aimed at investigating the carbon metabolism in terms of carbon dioxide fixation and its destination in microalgae cultivations. To this purpose, analysis of growth parameters, media of cultivation, biomass composition and productivity and nutrients balance were performed. Four microalgae suitable for mass cultivation were evaluated: Dunaliella tertiolecta SAD-13.86, Chlorella vulgaris LEB-104, Spirulina platensis LEB-52 and Botryococcus braunii SAG-30.81. Global rates of carbon dioxide and oxygen were determinated by a system developed in our laboratory. B. braunii presented the highest CO(2) fixation rate, followed by S. platensis,D. tertiolecta and C. vulgaris (496.98, 318.61, 272.4 and 251.64 mg L(-1)day(-1), respectively). Carbon dioxide fixated was mainly used for microalgal biomass production. Nitrogen, phosphorus (calcium for D. tertiolecta), potassium and magnesium consumption rates (mg gX(-1)) were evaluated for the four microalgae. Biomass composition presented a predominance of proteins but also a high amount of lipids, especially in D. tertiolecta and B. braunii. PMID:20350804

Sydney, Eduardo Bittencourt; Sturm, Wilerson; de Carvalho, Julio Cesar; Thomaz-Soccol, Vanete; Larroche, Christian; Pandey, Ashok; Soccol, Carlos Ricardo

2010-08-01

371

Soil carbon dioxide partial pressure and dissolved inorganic carbonate chemistry under elevated carbon dioxide and ozone.  

PubMed

Global emissions of atmospheric CO(2) and tropospheric O(3) are rising and expected to impact large areas of the Earth's forests. While CO(2) stimulates net primary production, O(3) reduces photosynthesis, altering plant C allocation and reducing ecosystem C storage. The effects of multiple air pollutants can alter belowground C allocation, leading to changes in the partial pressure of CO(2) (pCO(2)) in the soil , chemistry of dissolved inorganic carbonate (DIC) and the rate of mineral weathering. As this system represents a linkage between the long- and short-term C cycles and sequestration of atmospheric CO(2), changes in atmospheric chemistry that affect net primary production may alter the fate of C in these ecosystems. To date, little is known about the combined effects of elevated CO(2) and O(3) on the inorganic C cycle in forest systems. Free air CO(2) and O(3) enrichment (FACE) technology was used at the Aspen FACE project in Rhinelander, Wisconsin to understand how elevated atmospheric CO(2) and O(3) interact to alter pCO(2) and DIC concentrations in the soil. Ambient and elevated CO(2) levels were 360+/-16 and 542+/-81 microl l(-1), respectively; ambient and elevated O(3) levels were 33+/-14 and 49+/-24 nl l(-1), respectively. Measured concentrations of soil CO(2) and calculated concentrations of DIC increased over the growing season by 14 and 22%, respectively, under elevated atmospheric CO(2) and were unaffected by elevated tropospheric O(3). The increased concentration of DIC altered inorganic carbonate chemistry by increasing system total alkalinity by 210%, likely due to enhanced chemical weathering. The study also demonstrated the close coupling between the seasonal delta(13)C of soil pCO(2) and DIC, as a mixing model showed that new atmospheric CO(2) accounted for approximately 90% of the C leaving the system as DIC. This study illustrates the potential of using stable isotopic techniques and FACE technology to examine long- and short-term ecosystem C sequestration. PMID:15378342

Karberg, N J; Pregitzer, K S; King, J S; Friend, A L; Wood, J R

2005-01-01

372

The Fluid Mechanics of Carbon Dioxide Sequestration  

E-print Network

--water vapor (1.5­2% by volume), CO2 (0.04%), and methane (2 ppm)--have comparatively large effects, with methane having the largest effect per unit mass, although it deteriorates most rapidly of the three within the atmosphere. (Methane is 70 times more effective per unit mass as a greenhouse gas than CO2 over the first 20

Huppert, Herbert

373

CARBON DIOXIDE AND OUR OCEAN LEGACY  

E-print Network

. Ocean acidification, as the phenomenon is called, over time will create major negative impacts on corals. Ocean acidification and climate change are both effects of excessive carbon dumping into the atmosphere in 2003, and these numbers are growing every year.3 Ocean acidification is a straightforward consequence

374

[Roles of forest management in global carbon dioxide mitigation].  

PubMed

This paper summarized the roles of current forest management measures, e. g., reducing deforestation rate, increasing afforestation and reforestation, strengthening the management of nutrient fertilization, fire hazard, and disease and pest injury, and substituting fossils fuels with charcoal, in global carbon dioxide migration, and analyzed the advantage and insufficiency of China's forest management. The authors indicated that the current forest ecosystems in China, mainly their vegetation carbon pool, played a smaller role of carbon sink in global carbon cycle, and thus, it was important to strengthen the tending of newly cultivated plantation and the management of fire hazard and disease and pest injury, and to increase the carbon sequestration of our forests. PMID:16836107

Hu, Huifeng; Liu, Guohua

2006-04-01

375

CARBON DIOXIDE CAPTURE FROM FLUE GAS USING DRY REGENERABLE SORBENTS  

SciTech Connect

The objective of this project is to develop a simple, inexpensive process to separate CO{sub 2} as an essentially pure stream from a fossil fuel combustion system using a regenerable, sodium-based sorbent. The sorbent being used in this project is sodium carbonate which is converted to sodium bicarbonate, ''baking soda,'' through reaction with carbon dioxide and water vapor. Sodium bicarbonate is regenerated to sodium carbonate when heated, producing a nearly pure CO{sub 2} stream after condensation of water vapor. Testing conducted previously confirmed that the reaction rate and achievable CO{sub 2} capacity of sodium carbonate decreased with increasing temperature, and that the global rate of reaction of sodium carbonate to sodium bicarbonate increased with an increase in both CO{sub 2} and H{sub 2}O concentrations. Energy balance calculations indicated that the rate of heat removal from the particle surface may determine the reaction rate for a particular particle system. This quarter, thermogravimetric analyses (TGA) were conducted which indicated that calcination of sodium bicarbonate at temperatures as high as 200 C did not cause a significant decrease in activity in subsequent carbonation testing. When sodium bicarbonate was subjected to a five cycle calcination/carbonation test, activity declined slightly over the first two cycles but was constant thereafter. TGA tests were also conducted with two other potential sorbents. Potassium carbonate was found to be less active than sodium carbonate, at conditions of interest in preliminary TGA tests. Sodium carbonate monohydrate showed negligible activity. Testing was also conducted in a 2-inch internal diameter quartz fluidized-bed reactor system. A five cycle test demonstrated that initial removals of 10 to 15 percent of the carbon dioxide in a simulated flue gas could be achieved. The carbonation reaction proceeded at temperatures as low as 41 C. Future work by TGA and in fixed-bed, fluidized-bed, and transport reactor systems is planned to demonstrate the feasibility of this process in large scale operations to separate carbon dioxide from flue gas.

David A. Green; Brian S. Turk; Raghubir P. Gupta; Douglas P. Harrison; Ya Liang

2001-10-01

376

Concentration of carbon dioxide by a high-temperature electrochemical membrane cell  

Microsoft Academic Search

The electrochemical carbon dioxide concentrator has emerged over the last few years as the best technique for carbon dioxide control in a manned spacecraft. Preliminary investigations have shown that the Molten Carbonate Fuel Cell (MCFC) can be successfully converted into a molten carbonate CO2 concentrator (MCCDC) for CO2 removal from a space-cabin [1]. The present investigation involved studying the MCCDC

M. P. Kang; J. Winnick

1985-01-01

377

An optimal centralized carbon dioxide repository for Florida, USA.  

PubMed

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

Poiencot, Brandon; Brown, Christopher

2011-04-01

378

An Optimal Centralized Carbon Dioxide Repository for Florida, USA  

PubMed Central

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 Floridas 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

Poiencot, Brandon; Brown, Christopher

2011-01-01

379

Colored polymer microparticles through carbon dioxide-assisted dyeing  

SciTech Connect

A new procedure is described for dyeing polymer beads using liquid carbon dioxide as a plasticizer to facilitate transport of dye into the particle phase. Aqueous latexes consisting of monodisperse polystyrene particles with surface-grafted poly(N-vinylpyrrolidone) were dyed with Sudan Red 7B using CO{sub 2} at 25 C and 310 bar. Adding CO{sub 2} to the headspace above the latex resulted in some dyeing of the polymer, but better results were obtained by forming an emulsion of CO{sub 2} in the aqueous latex phase. Emulsions were formed with both a fluorinated and a hydrocarbon-based surfactant. It was found that the carbon dioxide emulsion greatly enhances the transfer of dye into the polystyrene without altering the size or morphology of the particles.

Yates, M.Z.; Birnbaum, E.R.; McCleskey, T.M.

2000-05-30

380

Carbon dioxide concentrations in the environment of sleeping infants.  

PubMed

In 22 infants continuous measurements were made of the concentration of carbon dioxide (CO2) in inspired air during sleep. Evidence was found of CO2 enrichment of inspired air in certain environmental conditions. The levels achieved were not sufficiently high to acutely endanger an infant. Carbon dioxide concentrations as high as 2-3% were observed in the prone position when the infant's head was under a blanket and when the lower face was obscured by bedding. Sleeping prone on a sheepskin also resulted in an increased concentration of CO2 but to a lesser extent than being under a blanket. In awake infants the presence of a pacifier also promoted an excess of CO2 in the inspired air, both in the prone and supine positions. The physiological and clinical implications of these findings, in relation to the Sudden Infant Death Syndrome (SIDS), are unknown and warrant investigation. PMID:8148189

Malcolm, G; Cohen, G; Henderson-Smart, D

1994-02-01

381

Carbon dioxide exchange in a temperate grassland ecosystem  

NASA Technical Reports Server (NTRS)

Carbon dioxide exchange was measured, using the eddy correlation technique, over a tallgrass prairie in northeastern Kansas, U.S.A., during a six-month period in 1987. The diurnal patterns of daytime and nocturnal CO2 fluxes are presented on eight selected days. These days were distributed throughout most of the growing season and covered a wide range of meteorological and soil water conditions. The midday CO2 flux reached a maximum of 1.3 mg/sq m (ground area)/s during early July and was near zero during the dry period in late July. The dependence of the daytime carbon dioxide exchange on pertinent controlling variables, particularly photosynthetically active radiation, vapor pressure deficit, and soil water content is discussed. The nocturnal CO2 flux (soil plus plant respiration) averaged -0.4 m sq m (ground area)/s during early July and was about -0.2 mg sq/m during the dry period.

Kim, Joon; Verma, Shashi B.

1990-01-01

382

Regenerable immobilized aminosilane sorbents for carbon dioxide capture applications  

SciTech Connect

A method for the separation of carbon dioxide from ambient air and flue gases is provided wherein a phase separating moiety with a second moiety are simultaneously coupled and bonded onto an inert substrate to create a mixture which is subsequently contacted with flue gases or ambient air. The phase-separating moiety is an amine whereas the second moiety is an aminosilane, or a Group 4 propoxide such as titanium (IV) propoxide (tetrapropyl orthotitanate, C.sub.12H.sub.28O.sub.4Ti). The second moiety makes the phase-separating moiety insoluble in the pores of the inert substrate. The new sorbents have a high carbon dioxide loading capacity and considerable stability over hundreds of cycles. The synthesis method is readily scalable for commercial and industrial production.

Gay, McMahan; Choi, Sunho; Jones, Christopher W

2014-09-16

383

Supercritical carbon dioxide extraction of solvent from micromachined structures  

SciTech Connect

We have demonstrated that supercritical carbon dioxide extraction can be used for solvent removal to successfully release compliant surface micromachined structures on silicon wafers developed at Sandia National Laboratories. Structures that have been successfully extracted and released include single gear microengines, bridge and cantilever beams, pressure transducers, and experimental comb drive actuators. Since the supercritical fluid has negligible surface tension, it has virtually unabated access to solvent residing in capillary-like spaces as narrow as 1--3 {mu}m under the micromachined features. While conventional drying techniques have been plagued with the collapse and sticking of micromachined structures due to surface tension effects, supercritical carbon dioxide has been shown to reproducibly dry components and test structures, including bridge and cantilever beams approaching 1000 {mu}m in length, without collapsing. The equipment and the extraction process are described, and photographs of supercritically dried test structures and components are presented.

Russick, E.M.; Adkins, C.L.J.; Dyck, C.W.

1995-12-31

384

High Levels of Carbon Dioxide Threaten Oyster Survival  

NSDL National Science Digital Library

It has been widely reported that the build up of carbon dioxide (CO2) in the air, which is caused by human behavior, will likely lead to climate change and have major implications for life on earth. But less focus has been given to global warmings evil twin, ocean acidification, which occurs when CO2 lowers the pH of water bodies, thus making them more acidic. This lesser known phenomenon may have catastrophic effects on all sea life. Inna Sokolova, associate professor of biology at the University of North Carolina at Charlotte, studies the affect of high carbon dioxide on oyster survival, growth and shell hardness. The results of her research suggest that creatures once thought to be fairly adaptable to changes in the environment, may be in serious trouble.

APS Communications Office (American Physiological Society Communications Office)

2010-08-04

385

Effect of carbon monoxide and nitrogen dioxide on ICR mice  

NASA Technical Reports Server (NTRS)

Times to incapacitation and death and LC(50) values were determined for male ICR mice exposed to different concentration of carbon monoxide for 30 min and of nitrogen dioxide for 10 min in a 4.2 liter hemispherical chamber. The data indicate that ICR mice are more resistant to these two toxicants than Swiss albino mice. The carbon monoxide LC(50) for a 30-min exposure was about 8,000 ppm for ICR mice compared to 3,570 ppm for Swiss albino mice. The nitrogen dioxide LC(50) for a 10-min exposure was above 2,000 ppm for ICR mice compared to about 1,000 ppm for Swiss albino mice.

Hilado, C. J.; Cumming, H. J.

1977-01-01

386

Carbon Dioxide Snow Storms During the Polar Night on Mars  

NASA Technical Reports Server (NTRS)

The Mars Orbiter Laser Altimeter (MOLA) detected clouds associated with topographic features during the polar night on Mars. While uplift generated from flow over mountains initiates clouds on both Earth and Mars, we suggest that the Martian clouds differ greatly from terrestrial mountain wave clouds. Terrestrial wave clouds are generally compact features with sharp edges due to the relatively small particles in them. However, we find that the large mass of condensible carbon dioxide on Mars leads to clouds with snow tails that may extend many kilometers down wind from the mountain and even reach the surface. Both the observations and the simulations suggest substantial carbon dioxide snow precipitation in association with the underlying topography. This precipitation deposits CO2, dust and water ice to the polar caps, and may lead to propagating geologic features in the Martian polar regions.

Toon, Owen B.; Colaprete, Anthony

2001-01-01

387

Microbial electrosynthesis of butyrate from carbon dioxide.  

PubMed

This work proves for the first time the bioelectrochemical production of butyrate from CO2 as a sole carbon source. The highest concentration of butyrate achieved was 20.2 mMC, with a maximum butyrate production rate of 1.82 mMC d(-1). The electrochemical characterisation demonstrated that the CO2 reduction to butyrate was hydrogen driven. Production of ethanol and butanol was also observed opening up the potential for biofuel production. PMID:25608945

Ganigu, R; Puig, S; Batlle-Vilanova, P; Balaguer, M D; Colprim, J

2015-02-01

388

Treatment of cutaneous leishmaniasis using a carbon dioxide laser.  

PubMed Central

Use of a carbon dioxide laser to vaporize the local lesions caused by cutaneous leishmaniasis is reported. A total of 108 patients have been treated in this way and followed up. The treatment reduces the management time of patients at least 1.5 times and is followed by satisfactory aesthetic outcomes. No recurrences have been observed among the 82 patients who have been followed up for 7 years. Images Fig. 1 Fig. 2 Fig. 3 PMID:1905204

Babajev, K. B.; Babajev, O. G.; Korepanov, V. I.

1991-01-01

389

Carbon Dioxide Separation with Supported Ionic Liquid Membranes  

SciTech Connect

Supported liquid membranes are a class of materials that allow the researcher to utilize the wealth of knowledge available on liquid properties as a direct guide in the development of a capture technology. These membranes also have the advantage of liquid phase diffusivities higher than those observed in polymeric membranes which grant proportionally greater permeabilities. The primary shortcoming of the supported liquid membranes demonstrated in past research has been the lack of stability caused by volatilization of the transport liquid. Ionic liquids, which possess high carbon dioxide solubility relative to light gases such as hydrogen, are an excellent candidate for this type of membrane since they have negligible vapor pressure and are not susceptible to evaporation. A study has been conducted evaluating the use of several ionic liquids, including 1-hexyl-3-methyl-imidazolium bis(trifuoromethylsulfonyl)imide, 1-butyl-3-methyl-imidazolium nitrate, and 1-ethyl-3-methyl-imidazolium sulfate in supported ionic liquid membranes for the capture of carbon dioxide from streams containing hydrogen. In a joint project, researchers at the University of Notre Dame lent expertise in ionic liquid synthesis and characterization, and researchers at the National Energy Technology Laboratory incorporated candidate ionic liquids into supports and evaluated the resulting materials for membrane performance. Initial results have been very promising with carbon dioxide permeabilities as high as 950 barrers and significant improvements in carbon dioxide/hydrogen selectivity over conventional polymers at 37C and at elevated temperatures. Results include a comparison of the performance of several ionic liquids and a number of supports as well as a discussion of innovative fabrication techniques currently under development.

Luebke, D.R.; Ilconich, J.B.; Myers, C.R.; Pennline, H.W.

2007-04-01

390

Deodorization and deacidification of edible oils with dense carbon dioxide  

Microsoft Academic Search

Near-critical carbon dioxide shows potential for extraction of free fatty acids, off-odors or flavors from edible fats and\\u000a oils. Deacidification and deodorization of a simulated, roasted peanut oil with dense CO2 was performed at various temperatures, pressures and extraction factors in a pilot-scale, packed extraction column with an\\u000a i.d. of 2.86 cm and a height of 162 cm. Pyrazine and

Gregory R. Ziegler; Yi-Jen Liaw

1993-01-01

391

Supercritical carbon dioxide extraction of caffeine from guaran  

Microsoft Academic Search

A single-pass system was designed to study extraction of caffeine from wet guaran seeds using supercritical carbon dioxide. Extraction was studied as a function of pressure and temperature to determine caffeine solubility at equilibrium conditions between 136.1 and 272.2 atm and temperatures of 35, 45, and 55 C. Solubility of caffeine into supercritical CO2 was affected directly by CO2 density.

H. D. Cochran; R BISWAL; J COLLINS

1996-01-01

392

Hot Stuff!: Testing for Carbon Dioxide from Our Own Breath  

NSDL National Science Digital Library

Learners blow into balloons and collect their breath--carbon dioxide gas (CO2). They then blow the CO2 from the balloon into a solution of acid-base indicator. The indicator changes color to show that CO2 gas in water forms an acid. This activity is part of a set of demonstrations and activities that can be used together for a larger lesson. Resource contains vocabulary definitions and suggestions for assessment, extensions, and scaling for different levels of learners.

2014-06-30

393

Treatment of fibroelastolytic papulosis with fractionated carbon dioxide laser.  

PubMed

Fibroelastolytic papulosis (FEP) is an acquired elastic tissue disorder that presents as white-to-yellow papules and plaques usually occurring on the neck. Although the lesions are often asymptomatic, their appearance may be distressing to patients. FEP has been treated with topical tretinoin in one case report ( 1 ). Other reports have not mentioned treatment for this rare disorder ( 1-6 ). We present a case of FEP successfully treated with a fractionated carbon dioxide (CO2) laser. PMID:25415242

Chong, Summer P; Woodley, David T; Kim, Gene H; Shim, Elisabeth K

2014-12-01

394

Supercritical carbon dioxide processed resorbable polymer nanocomposite bone graft substitutes  

Microsoft Academic Search

The development of synthetic bone graft substitutes is an intense area of research due to the complications associated with the harvest of autogenous bone and concerns about the supply of allogenic bone. Porous resorbable polymers have been used extensively in hard tissue engineering applications, but currently lack load-bearing capacity. Supercritical carbon dioxide (scCO2) processing is used as a novel method

Kevin C. Baker; Mihai Manitiu; Robert Bellair; Carly A. Gratopp; Harry N. Herkowitz; Rangaramanujam M. Kannan

2011-01-01

395

Intraoperative events diagnosed by expired carbon dioxide monitoring in children  

Microsoft Academic Search

Expired carbon dioxide measurements (PECO2) were used (1) to assess the adequacy of initial alveolar ventilation, and (2) to document intraoperative airway events and\\u000a metabolic trends. Three hundred and thirty-one children were studied. Thirty-five intraoperative events were diagnosed by\\u000a continuous PeCO2 monitoring; 20 were potentially life-threatening problems (malignant hyperthermia, circuit disconnection or leak, equipment\\u000a failure, accidental extubation, endobronchial intubation, or

Charles J. Cot; Letty M. P. Liu; Stanislaw K. Szyfelbein; Susan Firestone; Nishan G. Goudsouzian; James P. Welch; Alfred L. Daniels

1986-01-01

396

Copper-Catalyzed Carboxylation of Aryl Iodides with Carbon Dioxide  

PubMed Central

A method for carboxylation of aryl iodides with carbon dioxide has been developed. The reaction employs low loadings of copper iodide/TMEDA or DMEDA catalyst, 1 atm of CO2, DMSO or DMA solvent, and proceeds at 2570 C. Good functional group tolerance is observed, with ester, bromide, chloride, fluoride, ether, hydroxy, amino, and ketone functionalities tolerated. Additionally, hindered aryl iodides such as iodomesitylene can also be carboxylated PMID:24288654

Tran-Vu, Hung; Daugulis, Olafs

2013-01-01

397

Production and detection of carbon dioxide on Iapetus  

Microsoft Academic Search

Cassini VIMS detected carbon dioxide on the surface of Iapetus during its insertion orbit. We evaluated the CO2 distribution on Iapetus and determined that it is concentrated almost exclusively on Iapetus dark material. VIMS spectra show a 4.27-?m feature with an absorption depth of 24%, which, if it were in the form of free ice, requires a layer 31nm thick.

Eric E. Palmer; Robert H. Brown

2011-01-01

398

Upconverting nanoparticle based optical sensor for carbon dioxide  

Microsoft Academic Search

We demonstrate a novel optical sensor for carbon dioxide in concentrations between 0 and 3%. The sensing scheme is based on the optical interrogation of a 12-?m polystyrene (PS) film containing upconverting nanoparticles (UCNPs; 40100nm in size) of the type NaYF4:Yb,Er, and the longwave absorption pH probe bromothymol blue (BTB) in its anionic (blue) form. PS is chosen as a

Reham Ali; Sayed M. Saleh; Robert J. Meier; Hassan A. Azab; Ibraheim I. Abdelgawad; Otto S. Wolfbeis

2010-01-01

399

Methane conversion with carbon dioxide on nickel aluminides  

NASA Astrophysics Data System (ADS)

The catalytic activity of several samples based on nickel aluminides in methane conversion with carbon dioxide was studied. Nickel aluminides were prepared by the method of self-propagating high-temperature synthesis. The Ni3Al system containing the nickel metal phase exhibited high activity at temperatures above 1073 K. The systems based on Ni2Al3 and NiAl only containing intermetallic compound phases were inactive.

Arkatova, L. A.; Kharlamova, T. S.; Galaktionova, L. V.; Kurina, L. N.; Belousova, V. N.; Naiborodenko, Yu. S.; Kasatskii, N. G.; Golobokov, N. N.

2006-08-01

400

Volcanic carbon dioxide vents show ecosystem effects of ocean acidification  

Microsoft Academic Search

The atmospheric partial pressure of carbon dioxide (pCO2) will almost certainly be double that of pre-industrial levels by 2100 and will be considerably higher than at any time during the past few million years. The oceans are a principal sink for anthropogenic CO2 where it is estimated to have caused a 30% increase in the concentration of H+ in ocean

Jason M. Hall-Spencer; Riccardo Rodolfo-Metalpa; Sophie Martin; Emma Ransome; Maoz Fine; Suzanne M. Turner; Sonia J. Rowley; Dario Tedesco; Maria-Cristina Buia

2008-01-01

401

Environmental and societal consequences of a possible CO/sub 2/-induced climate change. Volume II, Part 14. Research needed to determine the present carbon balance of northern ecosystems and the potential effect of carbon-dioxide-induced climate change  

SciTech Connect

Given the potential significance of northern ecosystems to the global carbon budget it is critical to estimate the current carbon balance of these ecosystems as precisely as possible, to improve estimates of the future carbon balance if world climates change, and to assess the range of certainty associated with these estimates. As a first step toward quantifying some of the potential changes, a workshop with tundra and taiga ecologists and soil scientists was held in San Diego in March 1980. The first part of this report summarizes the conclusions of this workshop with regard to the estimate of the current areal extent and carbon content of the circumpolar arctic and the taiga, current rates of carbon accumulation in the peat in the arctic and the taiga, and predicted future carbon accumulation rates based on the present understanding of controlling processes and on the understanding of past climates and vegetation. This report presents a finer resolution of areal extents, standing crops, and production rates than was possible previously because of recent syntheses of data from the International Biological Program and current studies in the northern ecosystems, some of which have not yet been published. This recent information changes most of the earlier estimates of carbon content and affects predictions of the effect of climate change. The second part of this report outlines research needed to fill major gaps in the understanding of the role of northern ecosystems in global climate change.

Miller, P.C.

1982-10-01

402

Electrochemical Cell for Obtaining Oxygen from Carbon Dioxide Atmospheres  

NASA Technical Reports Server (NTRS)

To support human life on the Martian surface, an electrochemical device will be required to obtain oxygen from the carbon dioxide rich atmosphere. The electrolyte employed in such a device must be constructed from extremely thin, dense membranes to efficiently acquire the oxygen necessary to support life. A forming process used industrially in the production of multilayer capacitors and electronic substrates was adapted to form the thin membranes required. The process, known as the tape casting, involves the suspension consisting of solvents and binders. The suspension is passed under a blade, resulting in the production of ceramic membranes between 0.1 and 0.5 mm thick. Once fired, the stabilized zirconia membranes were assembled into the cell design by employing a zirconium phosphate solution as the sealing agent. The resulting ceramic-to-ceramic seals were found to be structurally sound and gas-tight. Furthermore, by using a zirconia-based solution to assemble the cell, the problem of a thermal expansion mismatch was alleviated. By adopting an industrial forming process to produce thin membranes, an electrochemical cell for obtaining oxygen from carbon dioxide was produced. The proposed cell design is unique in that it does not require a complicated manifold system for separating the various gases present in this process, nor does it require a series of complex electrical connections. Thus, the device can reliably obtain the vital oxygen supply from the toxic carbon dioxide atmosphere.

Hooker, Matthew; Rast, H. Edward; Rogers, Darren K.; Borja, Luis; Clark, Kevin; Fleming, Kimberly; Mcgurren, Michael; Oldaker, Tom; Sweet, Nanette

1989-01-01

403

Atlas of high resolution infrared spectra of carbon dioxide  

NASA Technical Reports Server (NTRS)

An atlas of long-path room-temperature absorption spectra of carbon dioxide is presented for the spectral intervals 1830-2100 cm, 2395-2680 cm, and 3140-3235 cm. The spectral data were recorded at high signal to noise with the 0.01 cm resolution Fourier transform interferometer. The spectra were obtained with pressures between 1 and 10 Torr of CO2 and with total paths between 24 and 384 meters. A compilation of the measured line positions and the assignments derived from the analysis are presented. Of the 3336 lines in the atlas, 94 percent were identified as CO2 lines or as residual lines H2O and CO. Calculated positions are presented for the carbon dioxide lines; a total of 52 bands of C-12O2-16, C-13O2-16, C-12O-16O-18, C-12O-16O-17, and C-13O-16O18 were identified. The weakest carbon dioxide lines marked in the atlas have intensities of approximately 0.5 x 10 to the negative 26th power cm/molecule at room temperature.

Rinsland, C. P.; Benner, D. C.; Devi, V. M.; Ferry, P. S.; Sutton, C. H.; Richardson, D. J.

1984-01-01

404

THE IMPROVED SYNTHESIS OF CARBONATED SOYBEAN OIL USING SUPERCRITICAL CARBON DIOXIDE AT A REDUCED REACTION TIME  

Technology Transfer Automated Retrieval System (TEKTRAN)

We have demonstrated at improved synthesis of a cyclic carbonate of soybean oil (CSO) utilizing supercritical carbon dioxide (CO2) as the solvent. Because the mutual solubility of supercritical CO2 and oil is significantly higher than that of the gas, our method synthesizes the material in ~1/3 of ...

405

Studies Regarding the Variation of Carbon Dioxide in Certain Carbonated Beverages Stored in Polyethylene Terephthalate Bottles  

Microsoft Academic Search

The necessity of storing carbonated beverages in more practical and lighter bottles has come to the replacement of the more traditional glass with the new PET (polyethylene terephthalate). Along with this change new problems have appeared regarding preservations of the beverage's qualities and the sensorial standard of quality. In this study is analysed the variation of carbon dioxide in certain

Mirel Glevitzky; Gabriela-Alina Brusturean; Delia Perju; Gheorghe Lasl?u; Loredana Matyas

406

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

Code of Federal Regulations, 2013 CFR

40 ? Protection of Environment ? 19 ? 2013-07-01 ? 2013-07-01 ? false ? Carbon monoxide and carbon dioxide analyzer specifications. ? 86.316-79 ? Section 86.316-79 ? Protection of Environment ? ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) ? AIR PROGRAMS (CONTINUED) ? CONTROL OF EMISSIONS FROM...

2013-07-01

407

Cyclic carbonate formation from carbon dioxide and oxiranes in tetrabutylammonium halides as solvents and catalysts.  

PubMed

[reaction: see text] Epoxides dissolved in molten tetralkylammonium salts bearing halides as counterions are converted into cyclic carbonates under atmospheric pressure of carbon dioxide. The reaction rate depends on the nucleophilicity of the halide ion as well as the structure of the cation. PMID:12123376

Cal, Vincenzo; Nacci, Angelo; Monopoli, Antonio; Fanizzi, Antonello

2002-07-25

408

SYNTHESIS OF CARBONATED FATTY METHYL ESTERS USING SUPERCRITICAL CARBON DIOXIDE  

Technology Transfer Automated Retrieval System (TEKTRAN)

The two step syntheses of the cyclic carbonates: carbonated methyl oleate (CMO) and carbonated methyl linoleate (CML) are reported. First, synthesis of the epoxide through well precedented chemical reaction of unsaturated fatty methyl esters with hydrogen peroxide and formic acid is performed. Nex...

409

Extraction of iron and calcium from low rank coal by supercritical carbon dioxide with entrainers  

SciTech Connect

Iron and calcium were extracted from low rank coal with supercritical carbon dioxide and methanol, ethanol, acetic acid, acetyl acetone, ethanol and acetic acid, or acetyl acetone and water entrainers at 313.2 K and 15.0 MPa. The low rank coal used in this study was Berau coal from Indonesia. The addition of methanol, ethanol, or acetic acid entrainers in supercritical carbon dioxide showed very limited effect on enhancement of the recovery rates of Fe. The recovery rates of Fe from dried coal by supercritical carbon dioxide with acetyl acetone were low however, the addition of acetyl acetone with water in supercritical carbon dioxide remarkably enhanced the recovery rates of Fe. Water seems to play an important role in extracting Fe from coal with supercritical carbon dioxide and acetyl acetone. On the other hand, the extraction rates of Ca with supercritical carbon dioxide and water, methanol, ethanol, and acetyl acetone entrainers were very low. The addition of acetic acid with or without water in supercritical carbon dioxide slightly enhanced the recovery rates of Ca. The addition of acetic acid with ethanol in supercritical carbon dioxide remarkably enhanced the recovery rates of Ca. The effect of carbon dioxide flow rate and coal particle size on the recovery rates of Fe were examined. The recovery rate of Fe increased with increasing carbon dioxide flow rate and with decreasing particle size of the low rank coal.

Iwai, Y.; Okamoto, N.; Ohta, S.; Arai, Y.; Sakanishi, K. [Kyushu University, Fukuoka (Japan). Dept. of Chemical Engineering

2007-03-15

410

Interaction of Carbon Dioxide with Cu Overlayers on Pt(111)  

SciTech Connect

The research described in this product was performed in part in the Environmental Molecular Sciences Laboratory, a national scientific user facility sponsored by the Department of Energy's Office of Biological and Environmental Research and located at Pacific Northwest National Laboratory. Experimental and theoretical studies on the interaction of carbon dioxide with pseudomorphic and rough copper layers deposited on a platinum (111) single crystal are reported. Evidence for carbon dioxide dissociation and carbonate formation is presented and the relevance to methanol synthesis is discussed. Intermediate species on the surfaces were identified using in situ polarization modulation infrared reflection absorption spectroscopy (PM-IRRAS) at pressures up to ?550 mbar and electron energy loss spectroscopy (EELS) in ultra-high vacuum. Temperature programmed desorption (TPD) reveals a broad high temperature desorption state for CO2 with peak maximum around 450 K. X-ray photoelectron spectroscopy (XPS) shows that approximately one third of the oxygen accumulated on the surface upon CO? exposure remains after TPD, indicative of carbonate formation via CO? dissociation supplying Oads and then facile CO?+Oads association, as well as subsequent decomposition at higher temperatures. Density functional theory studies of stepped Cu and Cu/Pt slabs reproduce vibrational frequencies of the carbonate, suggesting a nearly flat tridentate configuration at steps/defect sites.

Schumacher, N.; Andersson, Klas J.; Grabow, Lars C.; Mavrikakis, Manos; Nerlov, J.; Chorkendorff, I.

2008-02-01

411

CARBON DIOXIDE CAPTURE FROM FLUE GAS USING DRY REGENERABLE SORBENTS  

SciTech Connect

This report describes research conducted between January 1, 2004 and March 31, 2004 on the use of dry regenerable sorbents for removal of carbon dioxide from flue gas. RTI has produced laboratory scale batches (approximately 300 grams) of supported sorbents (composed of 20 to 40% sodium carbonate) with high surface area and acceptable activity. Initial rates of weight gain of the supported sorbents when exposed to a simulated flue gas exceeded that of 100% calcined sodium bicarbonate. One of these sorbents was tested through six cycles of carbonation/calcination by thermogravimetric analysis and found to have consistent carbonation activity. Kinetic modeling of the regeneration cycle on the basis of diffusion resistance at the particle surface is impractical, because the evolving gases have an identical composition to those assumed for the bulk fluidization gas. A kinetic model of the reaction has been developed on the basis of bulk motion of water and carbon dioxide at the particle surface (as opposed to control by gas diffusion). The model will be used to define the operating conditions in future laboratory- and pilot-scale testing.

David A. Green; Brian S. Turk; Jeffrey W. Portzer; Raghubir P. Gupta; William J. McMichael; Thomas Nelson

2004-04-01

412

System-Level Numerical Simulation of Geologic Storage of Carbon Dioxide Using a Brine and Carbon Dioxide Leakage Risk Analysis Model  

NASA Astrophysics Data System (ADS)

A series of system-level numerical simulations of geologic storage of carbon dioxide was performed using a brine and carbon dioxide leakage risk analysis model. This model is composed of three parts as a system. The first part is a process-level simulation of multiphase fluid flow and heat transport in a target storage formation. A multiphase thermo-hydrological numerical model TOUGH2 is implemented for the first part. The second part is a process-level simulation of brine and carbon dioxide leakage toward overlying aquifers and ground surfaces through wells and/or faults. A semi-analytical leakage model ELSA (Princeton Model) is implemented for the second part. The third part is a system-level probabilistic simulation of rates and amounts of brine and carbon dioxide leakage toward overlying aquifers and ground surfaces through wells and/or faults. A Monte Carlo probabilistic model is implemented for the third part. This model is applied to three different cases of hypothetical layered aquifer systems with alternation of sandstone (aquifer) and shale (aquitard). The first aquifer system is horizontal and has 100 abandoned wells. The second aquifer system is horizontal and has 100 abandoned wells and a fault. The third aquifer system is inclined and has 100 abandoned wells. For each case of the aquifer systems, the total simulation time period is set equal to 1,000 years including the carbon dioxide injection period of 50 years. The system-level numerical simulation results show that the carbon dioxide injection results in pore fluid pressure increase and thus causes brine and carbon dioxide leakage through the abandoned wells and/or fault. During the early time period, the pore fluid pressure increases in the target storage formation, and brine begins to leak through the abandoned wells and/or fault. Later, when the carbon dioxide plume reaches the bottom of the abandoned wells and/or fault, carbon dioxide begins to leak, and the brine leakage decreases. In addition, in case of the second aquifer system, the total amounts of brine and carbon dioxide leakage through the fault is 100 times greater than those through all the 100 abandoned wells. On the other hand, in case of the third aquifer system, significant amounts of brine and carbon dioxide leakage through the abandoned wells occur even after the carbon dioxide injection period. The results of this study validate the applicability of the system-level brine and carbon dioxide leakage risk analysis model to geologic storage of carbon dioxide. This work was supported by the Geo-Advanced Innovative Action (GAIA) Project, Korea Environmental Industry and Technology Institute (KEITI), Ministry of Environment, Republic of Korea.

Park, S.; Kihm, J.; Kim, J.

2012-12-01

413

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

NASA Astrophysics Data System (ADS)

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.

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

2014-12-01

414

Amazon River carbon dioxide outgassing fuelled by wetlands  

NASA Astrophysics Data System (ADS)

River systems connect the terrestrial biosphere, the atmosphere and the ocean in the global carbon cycle. A recent estimate suggests that up to 3 petagrams of carbon per year could be emitted as carbon dioxide (CO2) from global inland waters, offsetting the carbon uptake by terrestrial ecosystems. It is generally assumed that inland waters emit carbon that has been previously fixed upstream by land plant photosynthesis, then transferred to soils, and subsequently transported downstream in run-off. But at the scale of entire drainage basins, the lateral carbon fluxes carried by small rivers upstream do not account for all of the CO2 emitted from inundated areas downstream. Three-quarters of the world's flooded land consists of temporary wetlands, but the contribution of these productive ecosystems to the inland water carbon budget has been largely overlooked. Here we show that wetlands pump large amounts of atmospheric CO2 into river waters in the floodplains of the central Amazon. Flooded forests and floating vegetation export large amounts of carbon to river waters and the dissolved CO2 can be transported dozens to hundreds of kilometres downstream before being emitted. We estimate that Amazonian wetlands export half of their gross primary production to river waters as dissolved CO2 and organic carbon, compared with only a few per cent of gross primary production exported in upland (not flooded) ecosystems. Moreover, we suggest that wetland carbon export is potentially large enough to account for at least the 0.21 petagrams of carbon emitted per year as CO2 from the central Amazon River and its floodplains. Global carbon budgets should explicitly address temporary or vegetated flooded areas, because these ecosystems combine high aerial primary production with large, fast carbon export, potentially supporting a substantial fraction of CO2 evasion from inland waters.

Abril, Gwenal; Martinez, Jean-Michel; Artigas, L. Felipe; Moreira-Turcq, Patricia; Benedetti, Marc F.; Vidal, Luciana; Meziane, Tarik; Kim, Jung-Hyun; Bernardes, Marcelo C.; Savoye, Nicolas; Deborde, Jonathan; Souza, Edivaldo Lima; Albric, Patrick; Landim de Souza, Marcelo F.; Roland, Fabio

2014-01-01

415

Amazon River carbon dioxide outgassing fuelled by wetlands.  

PubMed

River systems connect the terrestrial biosphere, the atmosphere and the ocean in the global carbon cycle. A recent estimate suggests that up to 3 petagrams of carbon per year could be emitted as carbon dioxide (CO2) from global inland waters, offsetting the carbon uptake by terrestrial ecosystems. It is generally assumed that inland waters emit carbon that has been previously fixed upstream by land plant photosynthesis, then transferred to soils, and subsequently transported downstream in run-off. But at the scale of entire drainage basins, the lateral carbon fluxes carried by small rivers upstream do not account for all of the CO2 emitted from inundated areas downstream. Three-quarters of the world's flooded land consists of temporary wetlands, but the contribution of these productive ecosystems to the inland water carbon budget has been largely overlooked. Here we show that wetlands pump large amounts of atmospheric CO2 into river waters in the floodplains of the central Amazon. Flooded forests and floating vegetation export large amounts of carbon to river waters and the dissolved CO2 can be transported dozens to hundreds of kilometres downstream before being emitted. We estimate that Amazonian wetlands export half of their gross primary production to river waters as dissolved CO2 and organic carbon, compared with only a few per cent of gross primary production exported in upland (not flooded) ecosystems. Moreover, we suggest that wetland carbon export is potentially large enough to account for at least the 0.21 petagrams of carbon emitted per year as CO2 from the central Amazon River and its floodplains. Global carbon budgets should explicitly address temporary or vegetated flooded areas, because these ecosystems combine high aerial primary production with large, fast carbon export, potentially supporting a substantial fraction of CO2 evasion from inland waters. PMID:24336199

Abril, Gwenal; Martinez, Jean-Michel; Artigas, L Felipe; Moreira-Turcq, Patricia; Benedetti, Marc F; Vidal, Luciana; Meziane, Tarik; Kim, Jung-Hyun; Bernardes, Marcelo C; Savoye, Nicolas; Deborde, Jonathan; Souza, Edivaldo Lima; Albric, Patrick; Landim de Souza, Marcelo F; Roland, Fabio

2014-01-16

416

Upscaling carbon dioxide emissions from lakes  

NASA Astrophysics Data System (ADS)

CO2 fluxes from lakes to the atmosphere is important for balancing regional and global-scale carbon budgets. CO2 emissions are estimated through statistical upscaling procedures that aggregate data from a large number of lakes. However, aggregation can bias flux estimates if the physical and chemical factors determining CO2 exchange between water and the atmosphere are not independent. We evaluated the magnitude of aggregation biases with moment expansions and pCO2 data from 5140 Swedish lakes. The direction of the aggregation bias depends on lake size; mean flux was overestimated by 4% for small lakes (0.01-0.1 km2) but underestimated by 13% for large lakes (100-1000 km2). Simple covariance-based correction factors were generated to adjust for upscaling biases. These correction factors represent an easily interpretable and implemented approach to improving the accuracy of regional and global estimates of lake CO2 emissions.

Seekell, David A.; Carr, Joel A.; Gudasz, Cristian; Karlsson, Jan

2014-11-01

417

An advanced carbon reactor subsystem for carbon dioxide reduction  

NASA Technical Reports Server (NTRS)

An evaluation is presented of the development status of an advanced carbon-reactor subsystem (ACRS) for the production of water and dense, solid carbon from CO2 and hydrogen, as required in physiochemical air revitalization systems for long-duration manned space missions. The ACRS consists of a Sabatier Methanation Reactor (SMR) that reduces CO2 with hydrogen to form methane and water, a gas-liquid separator to remove product water from the methane, and a Carbon Formation Reactor (CFR) to pyrolize methane to carbon and hydrogen; the carbon is recycled to the SMR, while the produce carbon is periodically removed from the CFR. A preprototype ACRS under development for the NASA Space Station is described.

Noyes, Gary P.; Cusick, Robert J.

1986-01-01

418

CARBON DIOXIDE CAPTURE FROM FLUE GAS USING DRY REGENERABLE SORBENTS  

SciTech Connect

The objective of this project is to develop a simple and inexpensive process to separate CO{sub 2} as an essentially pure stream from a fossil fuel combustion system using a regenerable sorbent. The sorbents being investigated in this project are primarily alkali carbonates, and particularly sodium carbonate and potassium carbonate, which are converted to bicarbonates or intermediate salts through reaction with carbon dioxide and water vapor. Bicarbonates are regenerated to carbonates when heated, producing a nearly pure CO{sub 2} stream after condensation of water vapor. This quarter, electrobalance tests suggested that high calcination temperatures decrease the activity of sodium bicarbonate Grade 1 (SBC No.1) during subsequent carbonation cycles, but there is little or no progressive decrease in activity in successive cycles. SBC No.1 appears to be more active than SBC No.3. As expected, the presence of SO{sub 2} in simulated flue gas results in a progressive loss of sorbent capacity with increasing cycles. This is most likely due to an irreversible reaction to produce Na{sub 2}SO{sub 3}. This compound appears to be stable at calcination temperatures as high as 200 C. Tests of 40% supported potassium carbonate sorbent and plain support material suggest that some of the activity observed in tests of the supported sorbent may be due to adsorption by the support material rather than to carbonation of the sorbent.

David A. Green; Brian S. Turk; Jeffrey W. Portzer; Raghubir P. Gupta; William J. McMichael; Ya Liang; Douglas P. Harrison

2003-01-01

419

ARM Airborne Continuous carbon dioxide measurements  

SciTech Connect

The heart of the AOS CO2 Airborne Rack Mounted Analyzer System is the AOS Manifold. The AOS Manifold is a nickel coated aluminum analyzer and gas processor designed around two identical nickel-plated gas cells, one for reference gas and one for sample gas. The sample and reference cells are uniquely designed to provide optimal flushing efficiency. These cells are situated between a black-body radiation source and a photo-diode detection system. The AOS manifold also houses flow meters, pressure sensors and control valves. The exhaust from the analyzer flows into a buffer volume which allows for precise pressure control of the analyzer. The final piece of the analyzer is the demodulator board which is used to convert the DC signal generated by the analyzer into an AC response. The resulting output from the demodulator board is an averaged count of CO2 over a specified hertz cycle reported in volts and a corresponding temperature reading. The system computer is responsible for the input of commands and therefore works to control the unit functions such as flow rate, pressure, and valve control.The remainder of the system consists of compressors, reference gases, air drier, electrical cables, and the necessary connecting plumbing to provide a dry sample air stream and reference air streams to the AOS manifold.

Biraud, Sebastien

2013-03-26

420

ARM Airborne Continuous carbon dioxide measurements  

DOE Data Explorer

The heart of the AOS CO2 Airborne Rack Mounted Analyzer System is the AOS Manifold. The AOS Manifold is a nickel coated aluminum analyzer and gas processor designed around two identical nickel-plated gas cells, one for reference gas and one for sample gas. The sample and reference cells are uniquely designed to provide optimal flushing efficiency. These cells are situated between a black-body radiation source and a photo-diode detection system. The AOS manifold also houses flow meters, pressure sensors and control valves. The exhaust from the analyzer flows into a buffer volume which allows for precise pressure control of the analyzer. The final piece of the analyzer is the demodulator board which is used to convert the DC signal generated by the analyzer into an AC response. The resulting output from the demodulator board is an averaged count of CO2 over a specified hertz cycle reported in volts and a corresponding temperature reading. The system computer is responsible for the input of commands and therefore works to control the unit functions such as flow rate, pressure, and valve control.The remainder of the system consists of compressors, reference gases, air drier, electrical cables, and the necessary connecting plumbing to provide a dry sample air stream and reference air streams to the AOS manifold.

Biraud, Sebastien

421

Study on the gasification of wastepaper\\/carbon dioxide catalyzed by molten carbonate salts  

Microsoft Academic Search

This study focuses on waste paper gasification in carbon dioxide atmosphere with molten alkali carbonates including potassium, sodium, lithium carbonate or their intermixtures as catalyst. The molten catalysts is capable of facilitating a desired reaction (C+CO2?2CO), which was hardly feasible even at a high temperature of 973K if catalyst absences. It is that the catalysts which provides a gasliquid interface

Gong Jin; Hiroyuki Iwaki; Norio Arai; Kuniyuki Kitagawa

2005-01-01

422

Carbon Dioxide Fixation by Lupin Root Nodules  

PubMed Central

Labeling studies using detached lupin (Lupinus angustifolius) nodules showed that over times of less than 3 minutes, label from [3,4-14C]glucose was incorporated into amino acids, predominantly aspartic acid, to a much greater extent than into organic acids. Only a slight preferential incorporation was observed with [1-14C]- and [6-14C]glucose, while with [U-14C]-glucose more label was incorporated into organic acids than into amino acids at all labeling times. These results are consistent with a scheme whereby the carbon skeletons for amino acid synthesis are provided by the phosphoenolpyruvate carboxylase reaction. A comparison of 14CO2 release from nodules supplied with [1-14C]- and [6-14C]glucose indicated that the oxidative pentose phosphate pathway accounted for less than 6% of glucose metabolism. Several enzymes of the oxidative pentose phosphate and glycolytic pathways were assayed in vitro using the 12,000g supernatant fraction from nodule homogenates. In all cases, the specific activities were adequate to account for the calculated in vivo fluxes. Three out of four diverse treatments that inhibited nodule nitrogen fixation also inhibited nodule CO2 fixation, and in the case of the fourth treatment, replacement of N2 with He, it was shown that the normal entry of label from exogenous 14CO2 into the nodule amino acid pool was strongly inhibited. PMID:16660746

Laing, William A.; Christeller, John T.; Sutton, William D.

1979-01-01

423

Carbon dioxide emissions from Indian monsoonal estuaries  

NASA Astrophysics Data System (ADS)

Estuaries are known to be strong source for atmospheric CO2, however, little information is available from Indian estuaries. In order to quantify CO2 emissions from the Indian estuaries, samples were collected at 27 estuaries all along the Indian coast during discharge (wet) period. The emissions of CO2 to the atmosphere from Indian estuaries were 4-5 times higher during wet than dry period. The pCO2 ranged between 300 and 18492 ?atm which are within the range of world estuaries. The mean pCO2 and particulate organic carbon (POC) showed positive relation with rate of discharge suggesting availability of high quantities of organic matter that led to enhanced microbial decomposition. The annual CO2 fluxes from the Indian estuaries, together with dry period data available in the literature, amounts to 1.92 TgC which is >10 times less than that from the European estuaries. The low CO2 fluxes from the Indian estuaries are attributed to low flushing rates and less human settlements along the banks of the Indian estuaries.

Sarma, V. V. S. S.; Viswanadham, R.; Rao, G. D.; Prasad, V. R.; Kumar, B. S. K.; Naidu, S. A.; Kumar, N. A.; Rao, D. B.; Sridevi, T.; Krishna, M. S.; Reddy, N. P. C.; Sadhuram, Y.; Murty, T. V. R.

2012-02-01

424

Carbon Dioxide Capture from Flue Gas Using Dry, Regenerable Sorbents  

SciTech Connect

This report describes research conducted between October 1, 2005, and December 31, 2005, on the use of dry regenerable sorbents for removal of carbon dioxide (CO{sub 2}) from flue gas from coal combustion. A field test was conducted to examine the extent to which RTI's supported sorbent can be regenerated in a heated, hollow screw conveyor. This field test was conducted at the facilities of a screw conveyor manufacturer. The sorbent was essentially completely regenerated during this test, as confirmed by thermal desorption and mass spectroscopy analysis of the regenerated sorbent. Little or no sorbent attrition was observed during 24 passes through the heated screw conveyor system. Three downflow contactor absorption tests were conducted using calcined sodium bicarbonate as the absorbent. Maximum carbon dioxide removals of 57 and 91% from simulated flue gas were observed at near ambient temperatures with water-saturated gas. These tests demonstrated that calcined sodium carbonate is not as effective at removing CO{sub 2} as are supported sorbents containing 10 to 15% sodium carbonate. Delivery of the hollow screw conveyor for the laboratory-scale sorbent regeneration system was delayed; however, construction of other components of this system continued during the quarter.

David A. Green; Thomas O. Nelson; Brian S. Turk; Paul D. Box; Andreas Weber; Raghubir P. Gupta

2006-01-01

425

Mauna Loa, Hawaii: Carbon Dioxide Concentration (title provided or enhanced by cataloger)  

NSDL National Science Digital Library

This resource provides a graph of monthly average carbon dioxide (CO2) concentrations in ppmv (part per million by volume) versus time in years (1958 to 2000) at the Mauna Loa Observatory, Hawaii. This is a classic Earth science figure that illustrates the "breathing of the planet." The overall upward trend in CO2 concentrations since the 1950's is shown. The yearly cycle of C02 is shown in the yearly increases and decreases of C02. The increase of CO2 through the middle months of the year illustrates when the Northern Hemispheric forests have leaves and are "greening up".

Keeling, Charles; Whorf, Tim

2000-08-16

426

Carbon dioxide sequestration in cement kiln dust through mineral carbonation  

SciTech Connect

Carbon sequestration through the formation of carbonates is a potential means to reduce CO{sub 2} emissions. Alkaline industrial solid wastes typically have high mass fractions of reactive oxides that may not require preprocessing, making them an attractive source material for mineral carbonation. The degree of mineral carbonation achievable in cement kiln dust (CKD) under ambient temperatures and pressures was examined through a series of batch and column experiments. The overall extent and potential mechanisms and rate behavior of the carbonation process were assessed through a complementary set of analytical and empirical methods, including mass change, thermal analysis, and X-ray diffraction. The carbonation reactions were carried out primarily through the reaction of CO{sub 2} with Ca(OH){sub 2}, and CaCO{sub 3} was observed as the predominant carbonation product. A sequestration extent of over 60% was observed within 8 h of reaction without any modifications to the waste. Sequestration appears to follow unreacted core model theory where reaction kinetics are controlled by a first-order rate constant at early times; however, as carbonation progresses, the kinetics of the reaction are attenuated by the extent of the reaction due to diffusion control, with the extent of conversion never reaching completion. 35 refs., 3 figs., 1 tab.

Deborah N. Huntzinger; John S. Gierke; S. Komar Kawatra; Timothy C. Eisele; Lawrence L. Sutter [University of Michigan, Ann Arbor, MI (United States). Department of Civil and Environmental Engineering

2009-03-15

427

Prolonged suppression of ecosystem carbon dioxide uptake after an anomalously warm year  

E-print Network

LETTERS Prolonged suppression of ecosystem carbon dioxide uptake after an anomalously warm year , Yiqi Luo5 & David S. Schimel6 Terrestrial ecosystems control carbon dioxide fluxes to and from and heterotrophic respira- tion, that determines whether an ecosystem is sequestering carbon or releasing

Cai, Long

428

Carbon Dioxide Sequestering Using Microalgal Systems  

SciTech Connect

This project evaluated key design criteria, the technical feasibility, and the preliminary economic viability of a CO{sub 2}-sequestering system integrated with a coal-fired power plant based on microalgae biofixation. A review of relevant literature was conducted, and a bench-scale algal-based sequestration system was constructed and operated to verify algal growth capabilities using a simulated flue gas stream. The bench-scale system was a 20-gallon glass aquarium with a 16-gallon operating volume and was direct-sparged with a simulated flue gas. The flue gas composition was based on flue gas analyses for a 550-MW Coal Creek Power Station boiler in Underwood, North Dakota, which averaged 12.1% CO{sub 2}, 5.5% O{sub 2}, 423 ppm SO{sub 2}, 124 ppm NO{sub x}, and an estimated 50 mg/m{sup 3} fly ash loading. The algae were grown in Bold's basal growth medium. Lighting was provided using a two-tube fluorescent ''grow-light'' bulb fixture mounted directly above the tank. Algal growth appeared to be inhibited in the presence of SO{sub 2} using mixed cultures of green and blue-green cultures of algae. Samples of Monoraphidium strain MONOR02 and Nannochloropsis NANNO02 algal samples were obtained from the University of Hawaii Culture Collection. These samples did not exhibit inhibited growth in the presence of all the simulated flue gas constituents, but growth rates were somewhat lower than those expected, based on the review of literature. Samples of harvested algae were analyzed for protein, lipid, and carbohydrate content. A lipid content of 26% appeared to be fairly normal for algae, and it did not appear that large amounts of nitrogen were being fixed and promoting growth, nor were the algae starved for nitrogen. Proteins made up 41% of the total mass, and carbohydrates were assumed to be 33% (by difference). A preliminary economic analysis showed the costs of an integrated system based on microalgae biofixation to sequester 25% of the CO{sub 2} from a 550-MW coal-fired power plant could be recovered if the value recovered from the harvested algae was approximately $97. The analysis indicated the potential to produce 2427 tpd of algae at 12% moisture (2136 tpd dry weight). Of this, approximately 876 tpd of protein could be recovered and used as an animal feed. Similarly, an estimated 555 tpd of lipids could be recovered for use in the production of liquid fuels and chemicals. Approximately 705 tpd of carbohydrates would also be recovered. These carbohydrates may be suitable as a fermentation feedstock for the production of alcohols or organic acids.

Daniel J. Stepan; Richard E. Shockey; Thomas A. Moe; Ryan Dorn

2002-02-01

429

Method of determining pH by the alkaline absorption of carbon dioxide  

DOEpatents

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.

Hobbs, David T. (1867 Lodgepole Ave., N. Augusta, SC 29841)

1992-01-01

430

Remediation of Contaminated Soils By Supercritical Carbon Dioxide Extraction  

NASA Astrophysics Data System (ADS)

The contaminants that can be found in soils are many, inorganic, like heavy metals, as well as organic. Among the organic contaminants, oil and coal refineries are responsi- ble for several cases of soil contamination with PAHs (Polycyclic Aromatic Hydrocar- bons). Polynuclear aromatic hydrocarbons (PAHs) have toxic, carcinogenic and mu- tagenic effects. Limits have been set on the concentration of most contaminants, and growing concern is focusing on soil contamination issues. USA regulations set the maximum acceptable level of contamination by PAHs equal to 40 ppm at residential sites and 270 ppm at industrial sites. Stricter values are usually adopted in European Countries. Supercritical carbon dioxide extraction is a possible alternative technology to remove volatile organic compounds from contaminated soils. Supercritical fluid extraction (SFE) offers many advantages over conventional solvent extraction. Super- critical fluids combine gaseous properties as a high diffusion coefficient, and liquid properties as a high solvent power. The solvent power is strongly pressure-dependent near supercritical conditions: selective extractions are possible without changing the solvent. Solute can be separate from the solvent depressurising the system; therefore, it is possible to recycle the solvent and recover the contaminant. Carbon dioxide is frequently used as supercritical fluid, because it has moderate critical conditions, it is inert and available in pure form. In this work, supercritical fluid extraction technology has been used to remove a polynuclear aromatic hydrocarbon from contaminated soils. The contaminant choice for the experiment has been naphthalene since several data are available in literature. G. A. Montero et al. [1] studied soil remediation with supercrit- ical carbon dioxide extraction technology; these Authors have found that there was a mass-transfer limitation. In the extraction vessel, the mass transfer coefficient in- creases with the superficial velocity of the supercritical carbon dioxide; therefore, the mass transfer resistance can be reduced increasing such velocity. In this work, higher values of superficial velocity were investigated. The experimental apparatus includes a pump, an extraction vessel, an adjustable restrictor and a trap to collect the extracted substance. Liquid carbon dioxide coming from a cylinder with a dip-tube is cooled by a cryostatic bath and then it is compressed by a pneumatic drive pump (the max- imum available pressure is 69 MPa). Subsequently, the pressurised current flows into 1 a heating coil and then into the extraction vessel, which is contained in a stove; the outlet flow is depressurised in an adjustable restrictor and the extracted substance is collected in a trap by dissolution into a solvent. The extracted naphthalene quantity was obtained by weighting the solvent and measuring the naphthalene concentration with a gas chromatograph. The soil sample is a sandy soil geologically representative of the North of Italy that was sampled and physically and chemically characterized: particle-size distribution analysis, diffractometric analysis, Cation Exchange Capac- ity, Total Organic Carbon, iron content and manganese content in order to evaluate the potential sorption degree. The soil was artificially polluted by means of a naphta- lene and methylene chloride solution. The experimental work consists in a number of naphthalene extractions from the spiked soil, that were carried out at different operat- ing conditions, temperature, pressure and flow rate by means of supercritical carbon dioxide evaluating the corresponding recovery efficiencies. The results obtained were analysed and compared in order to determine which parameters influence the system. [1] G. A. Montero, T.D. Giorgio, and K. B. Schnelle, Jr..Removal of Hazardous ,1994, Contaminants form Soils by Supercritical Fluid Extraction. Innovations in Supercriti- cal Fluids. ACS Symposium Series, 608, 280-197. 2

Ferri, A.; Zanetti, M. C.; Banchero, M.; Fiore, S.; Manna, L.

431

Management Opportunities for Enhancing Terrestrial Carbon Dioxide Sinks  

SciTech Connect

The potential for mitigating increasing atmospheric carbon dioxide concentrations through the use of terrestrial biological carbon (C) sequestration is substantial. Here, we estimate the amount of C being sequestered by natural processes at global, North American, and national US scales. We present and quantify, where possible, the potential for deliberate human actions through forestry, agriculture, and use of biomass-based fuels to augment these natural sinks. Carbon sequestration may potentially be achieved through some of these activities but at the expense of substantial changes in land-use management. Some practices (eg reduced tillage, improved silviculture, woody bioenergy crops) are already being implemented because of their economic benefits and associated ecosystem services. Given their cumulative greenhouse-gas impacts, other strategies (eg the use of biochar and cellulosic bioenergy crops) require further evaluation to determine whether widespread implementation is warranted.

Post, W. M.; Izaurralde, Roberto C.; West, Tristram O.; Liebig, Mark A.; King, Anthony W.

2012-12-01

432

CARBON DIOXIDE MITIGATION THROUGH CONTROLLED PHOTOSYNTHESIS  

SciTech Connect

This research was undertaken to meet the need for a robust portfolio of carbon management options to ensure continued use of coal in electrical power generation. In response to this need, the Ohio Coal Research Center at Ohio University developed a novel technique to control the emissions of CO{sub 2} from fossil-fired power plants by growing organisms capable of converting CO{sub 2} to complex sugars through the process of photosynthesis. Once harvested, the organisms could be used in the production of fertilizer, as a biomass fuel, or fermented to produce alcohols. In this work, a mesophilic organism, Nostoc 86-3, was examined with respect to the use of thermophilic algae to recycle CO{sub 2} from scrubbed stack gases. The organisms were grown on stationary surfaces to facilitate algal stability and promote light distribution. The testing done throughout the year examined properties of CO{sub 2} concentration, temperature, light intensity, and light duration on process viability and the growth of the Nostoc. The results indicate that the Nostoc species is suitable only in a temperature range below 125 F, which may be practical given flue gas cooling. Further, results indicate that high lighting levels are not suitable for this organism, as bleaching occurs and growth rates are inhibited. Similarly, the organisms do not respond well to extended lighting durations, requiring a significant (greater than eight hour) dark cycle on a consistent basis. Other results indicate a relative insensitivity to CO{sub 2} levels between 7-12% and CO levels as high as 800 ppm. Other significant results alluded to previously, relate to the development of the overall process. Two processes developed during the year offer tremendous potential to enhance process viability. First, integration of solar collection and distribution technology from Oak Ridge laboratories could provide a significant space savings and enhanced use of solar energy. Second, the use of translating slug flow technology to cool the gas stream and enhance bicarbonate concentrations could both enhance organism growth rates and make the process one that could be applied at any fossil-fired power generation unit. These results were augmented by measurements of CO{sub 2} loss from the bioreactor test section. The corresponding mass balance was resolved to within 2%, which is remarkable for the low level of CO{sub 2} actually absorbed by the cyanobacteria. The net result was approximately 10.2 g of CO{sub 2} absorbed of the original 2.97 m{sup 3} of circulating flue gas, (or about 19% of the original CO{sub 2}). While this result in no way predicts the ability of the system to remove CO{sub 2} over the long term in a full-scale operating system, it appears to give credence to the workability of the system.

Unknown

2000-10-01

433

Blended polymer materials extractable with supercritical carbon dioxide  

NASA Astrophysics Data System (ADS)

Supercritical carbon dioxide is drawing more and more attention because of its unique solvent properties along with being environmentally friendly. Historically most of the commercial interests of supercritical carbon dioxide extraction are in the food industry, pharmaceutical industry, environmental preservation and polymer processing. Recently attention has shifted from the extraction of relatively simple molecules to more complex systems with a much broader range of physical and chemical transformations. However the available data show that a lot of commercially valuable substances are not soluble in supercritical carbon dioxide due to their polar structures. This fact really limits the application of SCF extraction technology to much broader industrial applications. Therefore, the study of a polymer's solubility in a given supercritical fluid and its thermodynamic behavior becomes one of the most important research topics. The major objective of this dissertation is to develop a convenient and economic way to enhance the polymer's solubility in supercritical carbon dioxide. Further objective is to innovate a new process of making metal casting parts with blended polymer materials developed in this study. The key technique developed in this study to change a polymer's solubility in SCF CO2 is to thermally blend a commercially available and CO2 non-soluble polymer material with a low molecular weight CO2 soluble organic chemical that acts as a co-solute. The mixture yields a plastic material that can be completely solubilized in SCF CO2 over a range of temperatures and pressures. It also exhibits a variety of physical properties (strength, hardness, viscosity, etc.) depending on variations in the mixture ratio. The three organic chemicals investigated as CO2 soluble materials are diphenyl carbonate, naphthalene, and benzophenone. Two commercial polymers, polyethylene glycol and polystyrene, have been investigated as CO2 non-soluble materials. The chemical, physical, thermal, and phase behavior of the blended polymers studied in this dissertation includes solubility in SCF CO2, the melt viscosity, the melting temperature depression, and phase equilibrium under SCF conditions. Several hypotheses are investigated to determine which mechanism plays the major role in the extraction. Finally a novel metal casting process is discussed with the materials developed in this study. This new method utilizes an adhesive or binder film composition for the purpose of building up a casting pattern of resin-bonded aggregate particles. The pattern is then encased in a conventional rigid shell mold that is not susceptible to degradation by SCF CO2. The pattern is then disintegrated within an unaffected mold by exposure to SCF CO 2. This is an efficient and low cost method of making patterns and molds, especially for the casting of a relatively low number of parts such as in prototype evaluations.

Cai, Mei

434

Progress in Measurement of Carbon Dioxide Using a Broadband Lidar  

NASA Technical Reports Server (NTRS)

In order to better understand the budget of carbon dioxide in the Earth's atmosphere it is necessary to develop a global high precision understanding of the carbon dioxide column. In order to uncover the 'missing sink" that is responsible for the large discrepancies in the budget as we presently understand it calculation has indicated that measurement accuracy on the order of 1 ppm is necessary. Because typical column average CO2 has now reached 380 ppm this represents a precision on the order of .25% for these column measurements. No species has ever been measured from space at such a precision. In recognition of the importance of understanding the CO2 budget in order to evaluate its impact on global warming the National Research Council in its decadal survey report to NASA recommended planning for a laser based total CO2 mapping mission in the near future. The extreme measurement accuracy requirements on this mission places very strong requirements on the laser system used for the measurement. This work presents an overview of the characteristics necessary in a laser system used to make this measurement. Consideration is given to the temperature dependence, pressure broadening, and pressure shift of the CO2 lines themselves and how these impact the laser system characteristics We have been examining the possibility of making precise measurements of atmospheric carbon dioxide using broad band source of radiation. This means that many of the difficulties in wavelength control can be treated in the detector portion of the system rather than the laser source. It also greatly reduces the number of individual lasers required to make a measurement. Simplifications such as these are extremely desirable for systems designed to operate from space.

Heaps, William S.

2010-01-01

435

Research Spotlight: Rain modifies ocean-atmosphere carbon dioxide exchange  

NASA Astrophysics Data System (ADS)

Exchanges of carbon dioxide (CO2) between the atmosphere and the oceans play an important role in the global carbon cycle and in determining how much CO2 is stored in the atmosphere and how much is stored in the ocean. A new study shows that rain can be an important, though often overlooked, factor in this exchange. Rain can contribute to the air-sea carbon exchange in several ways. Rain dilutes the CO2 in the surface layer of the ocean, increases the speed at which gas is transferred between the atmosphere and ocean, and deposits carbon from the atmosphere into the ocean. To determine the effects of rain on the air-sea carbon flux in the western equatorial Pacific, Turk et al. analyzed rain measurements from a buoy at 0, 156E during 2002 as well as a dilution model based on observational ocean studies and output from an ocean carbon cycle model. (Geophysical Research Letters, doi:10.1029/2010GL045520, 2010)

Tretkoff, Ernie

2011-01-01

436

Carbon dioxide laser treatment of erythroplasia of Queyrat.  

PubMed

We present a case of erythroplasia of Queyrat in a 77-year-old man involving the distal two-thirds of the penis. There was no urethral or periurethral involvement. Due to the location of the lesion, its recognition as carcinoma in situ, and the technical difficulty of cold-steel excision in this area, we used the carbon dioxide (CO2) laser to selectively destroy the tumor. In this case the laser provided controllable tissue destruction, ease of surgery, and excellent cosmesis. PMID:2501369

Greenbaum, S S; Glogau, R; Stegman, S J; Tromovitch, T A

1989-07-01

437

Methane-carbon dioxide-nitrogen mixtures as a fuel  

SciTech Connect

The presence of diluents such as carbon dioxide or nitrogen with methane is often encountered to varying proportions in numerous natural, industrial and bio-gases. The paper discusses how such a presence modifies significantly the thermo-dynamic, kinetic and combustion characteristics of methane in air. Experimental results are presented showing how the performance of engines of the spark ignition type are adversely affected by increasing the presence of diluents with the methane. The bases for these trends are discussed and some guidelines towards alleviating these adverse effects are made.

Karim, G.A.; Wierzba, I. [Univ. of Calgary, Alberta (Canada). Dept. of Mechanical Engineering

1996-10-01

438

Carbon-dioxide laser treatment of eye lid lesions.  

PubMed

A commercially available carbon-dioxide laser has been used in the treatment of basal cell carcinoma, capillary haemangioma, papilloma and various other neoplastic lesions involving the lids and paraocular skin. Altogether 20 patients have been treated in the past two years. The results have been very encouraging. All lesions have healed without scarring, and to date there have been no recurrences. The advantage of CO2 laser irradiation is coagulation of blood and lymphatic channels in the treatment area, which prevents bleeding and limits dissemination of tumour cells. Also discussed is the mechanism of CO2 laser and the possibilities for the future. PMID:3922095

Chopdar, A

1985-01-01

439

Complex of shikonin and ?-cyclodextrins by using supercritical carbon dioxide  

Microsoft Academic Search

\\u000a AbstractIn this work, the complex of shikonin-methyl-?-cyclodextrin and shikonin-2-hydroxypropyl-?-cyclodextrin were studied in supercritical\\u000a carbon dioxide (sc CO2) at moderate pressure and temperature much lower than the melting point of shikonin. For comparing, the complex was also\\u000a prepared by sealed heating method. Complex efficiency between shikonin and 2-hydroxypropyl-?-cyclodextrin (HPBCD) was quite\\u000a low. Partly formation of shikoninmethyl-?-cyclodextrin (MBCD) was obtained by sealed

Jun He

2009-01-01

440

Ion irradiation of ammonia/carbon dioxide mixtures  

NASA Astrophysics Data System (ADS)

We present new experimental results on the thermal and ion irradiation processing of ammonia/carbon dioxide frozen mixtures. Mixtures deposited at low T (16 K) have then been warmed up to 160 K. During warm up complex chemical reactions occur leading to the formation of new molecules and, in particular, of ammonium carbamate. Other samples have been irradiated with 144 keV S9+ ions. Also in this case new chemical species are formed among which CO and OCN-. The results are discussed in the light of their relevance to understand the effects of different processes going on in the variegated superficial and sub-superficial layers of Enceladus.

Lv, X. Y.; Boduch, P.; Ding, J. J.; Domaracka, A.; Langlinay, T.; Palumbo, M. E.; Rothard, H.; Strazzulla, G.

2013-09-01

441

Global carbon dioxide emission to the atmosphere by volcanoes  

SciTech Connect

Global emission of carbon dioxide by subaerial volcanoes is calculated, using CO{sub 2}/SO{sub 2} from volcanic gas analyses and SO{sub 2} flux, to be 34 {plus minus} 24 {times} 10{sup 12} g CO{sub 2}/yr from passive degassing and 31 {plus minus} 22 {times} 10{sup 12} g CO{sub 2}/yr from eruptions. Volcanic CO{sub 2} presently represents only 0.22% of anthropogenic emissions but may have contributed to significant greenhouse' effects at times in Earth history. Models of climate response to CO{sub 2} increases may be tested against geological data.

Williams, S.N.; Schaefer, S.J. (Arizona State Univ., Tempe (United States)); Calvache V., M.L. (Arizona State Univ., Tempe (United States) Observatorio Vulcanologico de Colombia, Pasto (Colombia)); Lopez, D. (Univ. of British Columbia, Vancouver (Canada))

1992-04-01

442

National assessment of geologic carbon dioxide storage resources: methodology implementation  

USGS Publications Warehouse

In response to the 2007 Energy Independence and Security Act, the U.S. Geological Survey (USGS) conducted a national assessment of potential geologic storage resources for carbon dioxide (CO2). Storage of CO2 in subsurface saline formations is one important method to reduce greenhouse gas emissions and curb global climate change. This report provides updates and implementation details of the assessment methodology of Brennan and others (2010, http://pubs.usgs.gov/of/2010/1127/) and describes the probabilistic model used to calculate potential storage resources in subsurface saline formations.

Blondes, Madalyn S.; Brennan, Sean T.; Merrill, Matthew D.; Buursink, Marc L.; Warwick, Peter D.; Cahan, Steven M.; Corum, Margo D.; Cook, Troy A.; Craddock, William H.; DeVera, Christina A.; Drake, Ronald M.; Drew, Lawrence J.; Freeman, Philip A.; Lohr, Celeste D.; Olea, Ricardo A.; Roberts-Ashby, Tina L.; Slucher, Ernie R.; and Varela, Brian A.

2013-01-01

443

A Review of Carbon Dioxide Selective Membranes: A Topical Report  

SciTech Connect

Carbon dioxide selective membranes provide a viable energy-saving alternative for CO2 separation, since membranes do not require any phase transformation. This review examines various CO2 selective membranes for the separation of CO2 and N2, CO2 and CH4, and CO2 and H2 from flue or fuel gas. This review attempts to summarize recent significant advances reported in the literature about various CO2 selective membranes, their stability, the effect of different parameters on the performance of the membrane, the structure and permeation properties relationships, and the transport mechanism applied in different CO2 selective membranes.

Dushyant Shekhawat; David R. Luebke; Henry W. Pennline

2003-12-01

444

Nonlinear carbon dioxide at high pressures and temperatures.  

PubMed

A nonlinear molecular carbon dioxide phase IV was discovered by laser heating CO2-III (Cmca) between 12 and 30 GPa, followed by quenching to 300 K. The Raman spectrum of quenched CO2-IV exhibits a triplet bending mode nu2(O = C = O) near 650 cm (-1), suggesting a broken inversion symmetry because of bending. The 650 cm (-1) bending modes soften with increasing pressure, indicating an enhanced intermolecular interaction among neighboring bent CO2 molecules. At 80 GPa, the low-frequency vibron collapses into high-frequency phonons, and CO2-IV becomes an extended amorphous solid. PMID:11177851

Yoo, C S; Iota, V; Cynn, H

2001-01-15

445

Comparison of Carbon Dioxide Solubility Models in Brine for Use in Carbon Sequestration Reservoir Estimates  

NASA Astrophysics Data System (ADS)

Carbon sequestration into deep geological formations, such as saline formations and oil and gas fields, is a promising method to mitigate global warming. Estimating carbon dioxide solubility (TPX) in brine under carbon sequestration conditions with high temperature, pressure and salinity is crucial in choosing suitable carbon sequestration reservoirs and determining the carbon dioxide storage capacity of each. Multiple mathematical models are available for predicting the solubility of CO2 in brine. Although comparisons of each model with a particular experimental data set collected under certain TPX conditions have been published by the model developers, few studies have been done to compare these models using a comprehensive experimental data set and rigorous statistical methods. In this study, available CO2 solubility experimental data and nine mathematical models for the prediction of CO2 solubility in brine were collected. Five of these predictive models are empirical or semi-empirical and the remainders are based on different equations of state. Statistical criteria, such as the AIC and BIC were employed to determine the goodness of fit of each mathematical model with the CO2 solubility experimental data set. Results of this analysis determine the best mathematical predictive model for the calculation of carbon dioxide solubility under carbon sequestration conditions. Preliminary analysis shows that simplified models with fewer variables perform equally well with those having more. The study also presents a quantitative approach to determine the best CO2 solubility predictive model through use of a regression tree.

Karamalidis, A.; Wang, Z.; Small, M.; Dilmore, R. M.; Goodman, A. L.

2011-12-01

446

The Carbon-Nitrogen Balance of the Nodule and Its Regulation under Elevated Carbon Dioxide Concentration  

PubMed Central

Legumes have developed a unique way to interact with bacteria: in addition to preventing infection from pathogenic bacteria like any other plant, legumes also developed a mutualistic symbiotic relationship with one gender of soil bacteria: rhizobium. This interaction leads to the development of a new root organ, the nodule, where the differentiated bacteria fix for the plant the atmospheric dinitrogen (atmN2). In exchange, the symbiont will benefit from a permanent source of carbon compounds, products of the photosynthesis. The substantial amounts of fixed carbon dioxide dedicated to the symbiont imposed to the plant a tight regulation of the nodulation process to balance carbon and nitrogen incomes and outcomes. Climate change including the increase of the concentration of the atmospheric carbon dioxide is going to modify the rates of plant photosynthesis, the balance between nitrogen and carbon, and, as a consequence, the regulatory mechanisms of the nodulation process. This review focuses on the regulatory mechanisms controlling carbon/nitrogen balances in the context of legume nodulation and discusses how the change in atmospheric carbon dioxide concentration could affect nodulation efficiency. PMID:24987690

2014-01-01

447

Corrosion of carbon steel in an aqueous carbon dioxide environment  

Microsoft Academic Search

A water phase during the travel in long gas transport pipes will accumulate increasing amounts of Fe\\/sup 2+\\/ corrosion product. For a pipeline with an unprocessed well stream of gas, liquid hydrocarbon, and condensed water, the Fe\\/sup 2+\\/ buildup in the water phase can have a major influence on the corrosion of carbon steel. The most important effect is that

K. Videm; A. Dugstad

1989-01-01

448

Conversion of carbon dioxide to oxaloacetate using integrated carbonic anhydrase and phosphoenolpyruvate carboxylase.  

PubMed

The development and implementation of strategies for CO2 mitigation are necessary to counteract the greenhouse gas effect of carbon dioxide emissions. To demonstrate the possibility of simultaneously capturing CO2 and utilizing four-carbon compounds, an integrated system using CA and PEPCase was developed, which mimics an in vivo carbon dioxide concentration mechanism. We first cloned the PEPCase 1 gene of the marine diatom Phaeodactylum tricornutum and produced a recombinant PtPEPCase 1. The affinity column purified PtPEPCase 1 exhibited specific enzymatic activity (5.89 U/mg). When the simultaneous and coordinated reactions of CA from Dunaliella sp. and the PtPEPCase 1 occurred, more OAA was produced than when only PEPCase was present. Therefore, this integrated CA-PEPCase system can be used not only to capture CO2 but also for a new technology to produce value-added four-carbon platform chemicals. PMID:23689757

Chang, Kwang Suk; Jeon, Hancheol; Gu, Man Bock; Pack, Seung Pil; Jin, EonSeon

2013-12-01

449

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

NASA Technical Reports Server (NTRS)

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.

Green, Robert O.

2001-01-01

450

CARBON DIOXIDE CAPTURE FROM FLUE GAS USING DRY REGENERABLE SORBENTS  

SciTech Connect

The objective of this project is to develop a simple, inexpensive process to separate CO{sub 2} as an essentially pure stream from a fossil fuel combustion system using a regenerable, sodium-based sorbent. The sorbent being used in this project is sodium carbonate which is converted to sodium bicarbonate, or ''baking soda,'' through reaction with carbon dioxide and water vapor. Sodium bicarbonate is regenerated to sodium carbonate when heated, producing a nearly pure CO{sub 2} stream after condensation of water vapor. This quarter, five cycle thermogravimetric tests were conducted at the Louisiana State University (LSU) with sodium bicarbonate Grade 3 (SBC{number_sign}3) which showed that carbonation activity declined slightly over 5 cycles following severe calcination conditions of 200 C in pure CO{sub 2}. Three different sets of calcination conditions were tested. Initial carbonation activity (as measured by extent of reaction in the first 25 minutes) was greatest subsequent to calcination at 120 C in He, slightly less subsequent to calcination in 80% CO{sub 2}/20% H{sub 2}O, and lowest subsequent to calcination in pure CO{sub 2} at 200 C. Differences in the extent of reaction after 150 minutes of carbonation, subsequent to calcination under the same conditions followed the same trend but were less significant. The differences between fractional carbonation under the three calcination conditions declined with increasing cycles. A preliminary fixed bed reactor test was also conducted at LSU. Following calcination, the sorbent removed approximately 19% of the CO{sub 2} in the simulated flue gas. CO{sub 2} evolved during subsequent calcination was consistent with an extent of carbonation of approximately 49%. Following successful testing of SBC{number_sign}3 sorbent at RTI reported in the last quarter, a two cycle fluidized bed reactor test was conducted with trona as the sorbent precursor, which was calcined to sodium carbonate. In the first carbonation cycle, CO{sub 2} removal rates declined from 20% to about 8% over the course of three hours. Following calcination, a second carbonation cycle was conducted, at a lower temperature with a lower water vapor content. CO{sub 2} removal and sorbent capacity utilization declined under these conditions. Modifications were made to the reactor to permit addition of extra water for testing in the next quarter. Thermodynamic analysis of the carbonation reaction suggested the importance of other phases, intermediate between sodium carbonate and sodium bicarbonate, and the potential for misapplication of thermodynamic data from the literature. An analysis of initial rate data from TGA experiments suggested that the data may fit a model controlled by the heat transfer from the sorbent particle surface to the bulk gas.

David A. Green; Brian S. Turk; Raghubir P. Gupta; William J. McMichael; Douglas P. Harrison; Ya Liang

2002-01-01

451

Transport Models for Radioactive Carbon Dioxide at RWMC  

SciTech Connect

Radioactive carbon dioxide (formed by oxidation of carbon-14) is a highly mobile, radioactive contaminant released from solid wastes buried at the Subsurface Disposal Area (SDA) at the Radioactive Waste Management Complex (RWMC) at the Idaho National Engineering and Environmental Laboratory (INEEL). Radioactive CO2 is chemically active in the environment, volatile, water soluble, and subject to adsorption on solids. For this reason, its fate must be understood and controlled to meet radiological requirements (protection of the atmosphere, aquifer, vadose zones, plants and animals). In the present work, the migration of carbon-14 as dissolved bicarbonate was studied using miscible displacement experiments in water-saturated columns containing sediments from RWMC. Dissolved carbon-14 was retarded relative to the movement of water by a factor of about 3.6, which translates to a partition coefficient (Kd) of 0.8 ml/g. Two different adsorption sites were identified, with one site possibly having a nonlinear adsorption isotherm. A conservative tracer gas, sulfur hexafluoride, was used to measure the tortuosity of sedimentary material for gaseous diffusion. The tortuosity of the RWMC sediment (Spreading Area B sediment) was determined to be 3.2, which is slightly greater than predicted by the commonly used Millington-Quirk equation. In terms of affecting the migration of carbon-14 to the aquifer, the relative importance of the parameters studied is: (1) natural moisture content of the sediments, (2) sediment tortuosity to gas-phase diffusion, and (3) adsorption onto solid phases.

Hull, Laurence Charles; Hohorst, Frederick August

2001-12-01

452

Carbon dioxide and methane dynamics and annual carbon balance in tundra wetland in NE Europe, Russia  

Microsoft Academic Search

Methane (CH4) and carbon dioxide (CO2) fluxes on east European tundra wetland ecosystems (6723N, 6322E) were measured by static chamber techniques in 1999. The 29 microsites were divided into wet flarks (WF), intermediate flarks (IF), wet lawns (WL), intermediate lawns (IL), and hummocks (HCK) in accordance to the water table (WT) and vegetation. The seasonal net ecosystem exchange (NEE) varied

Juha E. P. Heikkinen; Vladimir Elsakov; Pertti J. Martikainen

2002-01-01

453

Numerical Simulation of Behavior of Carbon Dioxide Injected into Target Geologic Formations in the Bukpyeong Basin, Korea  

NASA Astrophysics Data System (ADS)

A series of thermo-hydrological numerical simulations was performed to predict and analyze behavior of carbon dioxide injected into target geologic formations in the Bukpyeong Basin, which is one of the prospective offshore basins for geologic carbon dioxide storage in Korea. The results of the numerical simulations for the two areas in the basin show that the spatial distribution, structure (layered structure), and hydrological properties (anisotropy of intrinsic permeability) of the target geologic formations have significant impacts on three-dimensional behavior of carbon dioxide injected. The horizontal movement of carbon dioxide along the spatial distribution of a target geologic formation (Unit C-4) is more dominant than the vertical movement. As the injection amount of carbon dioxide increases, carbon dioxide plume expands furthermore and reaches to the shallower depth region from the mean sea level. Even in case of the maximum injection amount of carbon dioxide, carbon dioxide does not leak through the top boundary (sea floor) of the modeling domain for both areas. It indicates that carbon dioxide can be stored in the two areas up to their effective storage capacities of free fluid phase carbon dioxide, which was estimated in authors' previous study. As time progresses, carbon dioxide stored by hydrodynamic trapping decreases, while carbon dioxide stored by solubility trapping increases. The total mass of carbon dioxide stored by solubility trapping evaluated in this study is significantly greater than that estimated in authors' previous study. It indicates that the storage efficiency of aqueous phase carbon dioxide is greater than that of free fluid phase carbon dioxide. Therefore, this difference in the storage efficiencies of the free fluid and aqueous phases of carbon dioxide must be properly considered when more rigorous effective storage capacities of carbon dioxide are to be estimated on basin and even site scales. This work was supported by the Energy Efficiency and Resources Program funded by the Korea Institute of Energy Technology Evaluation and Planning (KETEP), Ministry of Trade, Industry and Energy, Republic of Korea.

Kihm, J.; Park, S.; Kim, J.

2013-12-01

454

Molecular Design of Intercalation-Based Sensors. 2. Sensing of Carbon Dioxide in Functionalized  

E-print Network

in the carbonated beverage industry and for the production of carbon- ates, carboxylic acids, carbon monoxideMolecular Design of Intercalation-Based Sensors. 2. Sensing of Carbon Dioxide in Functionalized)methyldihydroxysilane, and p-xylylene- diamine, and their reversible reaction with CO2 to form carbonates and carbamates

455

The Potential of Clear Sky Carbon Dioxide Satellite Retrievals  

NASA Astrophysics Data System (ADS)

It has been shown that neglecting scattering and absorption by aerosols and thin clouds can lead to significant errors in retrievals of the column-averaged dry-air mole fraction of carbon dioxide (XCO2) from space-based measurements of near-infrared reflected sunlight. These clear sky retrievals, which assume no aerosol effects, are desirable because of their high computational efficiency relative to common full physics retrievals. Further, clear sky retrievals may be able to make higher quality measurements relative to the full physics approach because they may introduce fewer potential biases under certain circumstances. These biases can appear when we try to retrieve clouds and aerosols in the full physics methods when there are none actually present. Recent work has shown that intelligent pre-screening can remove soundings with large light-path modifications over ocean surfaces. In this work, we test the hypothesis that intelligent pre-screening of soundings may be successfully used over land surfaces as well as oceans, which would allow clear sky retrievals to be applicable over all surfaces. We also test the hypothesis that major light path modification effects associated with aerosols can be identified based on spectral tests at 0.76, 1.6, and 2 microns. This presentation summarizes our study of both simulated data and satellite observations from the GOSAT instrument in order to assess the effectiveness of using a clear sky retrieval algorithm coupled with intelligent pre-screening to accurately measure carbon dioxide from space-borne instruments.

Nelson, R.; O'Dell, C.

2013-12-01

456

Supercritical carbon dioxide extraction of fucoxanthin from Undaria pinnatifida.  

PubMed

Undaria pinnatifida, commonly known as wakame in Japan, is one species of brown seaweeds containing valuable bioactive organic compounds such as fucoxanthin, a carotenoid, which has numerous functional properties. However, most of the seaweeds that do not meet strict quality standards are normally discarded as wastes or returned to the sea, a situation which is becoming an environmental concern. In this research, supercritical carbon dioxide (SCCO?) extraction was investigated for the isolation of fucoxanthin. SCCO? extraction experiments were carried out at temperature range of 25-60 C and pressure range of 20-40 MPa, at a carbon dioxide flow rate of 1.0-4.0 mL/min. Results showed that fucoxanthin recovery closed to 80% could be obtained at 40 C and 40 MPa in extraction time of 180 min. The recovery increased with decreasing temperature and increasing pressure. Pretreatment with microwave (MW) also enhanced the efficiency of extraction due most likely to disruption of the cell membrane. Application of SCCO?, generally regarded as safe and environmentally benign solvent, for extraction of useful bioactive compounds from unwanted or substandard seaweeds look promising in the near future. The extracts obtained using the method can be utilized as food and pharmaceutical additive, and can be used in the development of new health supplements. PMID:23742680

Quitain, Armando T; Kai, Takahisa; Sasaki, Mitsuru; Goto, Motonobu

2013-06-19

457

Measurement of Carbon Dioxide Column via Space Borne Laser Absorption  

NASA Technical Reports Server (NTRS)

In order to better understand the budget of carbon dioxide in the Earth's atmosphere it is necessary to develop a global high precision understanding of the carbon dioxide column. In order to uncover the 'missing sink that is responsible for the large discrepancies in the budget as we presently understand it calculation has indicated that measurement accuracy on the order of 1 ppm is necessary. Because typical column average CO2 has now reached 380 ppm this represents a precision on the order of .25% for these column measurements. No species has ever been measured from space at such a precision. In recognition of the importance of understanding the CO2 budget in order to evaluate its impact on global warming the National Research Council in its decadal survey report to NASA recommended planning for a laser based total CO2 mapping mission in the near future. The extreme measurement accuracy requirements on this mission places very strong requirements on the laser system used for the measurement. This work presents an analysis of the characteristics necessary in a laser system used to make this measurement. Consideration is given to the temperature dependence, pressure broadening, and pressure shift of the CO2 lines themselves and how these impact the laser system characteristics Several systems for meeting these requirements that are under investigation at various institutions in the US as well as Europe will be discussed.

Heaps, WIlliam S.

2007-01-01

458

Ammonia and Carbon Dioxide Concentrations in a Layer House  

PubMed Central

Higher concentrations of ammonia (NH3) and carbon dioxide (CO2) in animal barns can negatively affect production and health of animals and workers. This paper focuses on measurements of summer concentrations of ammonia (NH3) and carbon dioxide (CO2) in a naturally ventilated laying henhouse located at an egg production facility in Bursa region, western Turkey. Also, indoor and ambient environmental conditions such as temperature and relative humidity were measured simultaneously with pollutant gas concentrations. The average NH3 concentrations during summer of 2013 was 8.05 ppm for exhaust and 5.42 ppm for inlet while average CO2 concentration was 732 ppm for exhaust and 625 ppm for inlet throughout summer. The overall minimum, average and maximum values and humidity were obtained as 16.8C, 24.72C, and 34.71C for indoor temperature and 33.64%, 63.71%, and 86.18% for relative humidity. The lowest exhaust concentrations for NH3 and CO2 were 6.98 ppm and 609 ppm, respectively. They were measured in early morning at the maximum diurnal ventilation rate in July 2013 and August 2013. The highest concentrations were 10.58 ppm for NH3 and 904 ppm for CO2 recorded in the afternoon when the ventilation rate was the lowest in June 2013. PMID:25083117

Kilic, Ilker; Yaslioglu, Erkan

2014-01-01

459

Carbon Dioxide Information Analysis Center: FY 1991 activities  

SciTech Connect

During the course of a fiscal year, Oak Ridge National Laboratory`s Carbon Dioxide Information Analysis Center (CDIAC) distributes thousands of specially publications-numeric data packages (NDPs), computer model packages (CMPs), technical reports, public communication publications, newsletters, article reprints, and reference books-in response to requests for information related to global environmental issues, primarily those pertaining to climate change. CDIAC`s staff also provides technical responses to specific inquiries related to carbon dioxide (CO{sub 2}), other trace gases, and climate. Hundreds of referrals to other researchers, policy analysts, information specialists, or organizations are also facilitated by CDIAC`s staff. This report provides an account of the activities accomplished by CDIAC during the period October 1, 1990 to September 30, 1991. An organizational overview of CDIAC and its staff is supplemented by a detailed description of inquiries received and CDIAC`s response to those inquiries. An analysis and description of the preparation and distribution of numeric data packages, computer model packages, technical reports, newsletters, factsheets, specially publications, and reprints is provided. Comments and descriptions of CDIAC`s information management systems, professional networking, and special bilateral agreements are also described.

Cushman, R.M.; Stoss, F.W.

1992-06-01

460

Carbon Dioxide Information Analysis Center: FY 1991 activities  

SciTech Connect

During the course of a fiscal year, Oak Ridge National Laboratory's Carbon Dioxide Information Analysis Center (CDIAC) distributes thousands of specially publications-numeric data packages (NDPs), computer model packages (CMPs), technical reports, public communication publications, newsletters, article reprints, and reference books-in response to requests for information related to global environmental issues, primarily those pertaining to climate change. CDIAC's staff also provides technical responses to specific inquiries related to carbon dioxide (CO{sub 2}), other trace gases, and climate. Hundreds of referrals to other researchers, policy analysts, information specialists, or organizations are also facilitated by CDIAC's staff. This report provides an account of the activities accomplished by CDIAC during the period October 1, 1990 to September 30, 1991. An organizational overview of CDIAC and its staff is supplemented by a detailed description of inquiries received and CDIAC's response to those inquiries. An analysis and description of the preparation and distribution of numeric data packages, computer model packages, technical reports, newsletters, factsheets, specially publications, and reprints is provided. Comments and descriptions of CDIAC's information management systems, professional networking, and special bilateral agreements are also described.

Cushman, R.M.; Stoss, F.W.

1992-06-01

461

Climate change, carbon dioxide, and global crop production: Adaptation to uncertainty  

Technology Transfer Automated Retrieval System (TEKTRAN)

Documented and projected changes in atmospheric carbon dioxide are likely to alter agricultural productivity in two ways: directly, by supplying additional carbon for photosynthesis and growth, and indirectly by altering climate, specifically surface temperatures and precipitation. In this overview...

462

Estimation of Geologic Storage Capacity of Carbon Dioxide in the Bukpyeong Basin, Korea Using Integrated Three-Dimensional Geologic Formation Modeling and Thermo-Hydrological Numerical Modeling  

NASA Astrophysics Data System (ADS)

A conventional method, which was suggested by NETL (2007), has been widely used for estimating the geologic storage capacity of carbon dioxide in sedimentary basins. Because of its simple procedure, it has been straightforwardly applied to even spatially very complicate sedimentary basins. Thus, the results from the conventional method are often not accurate and reliable because it can not consider spatial distributions of fluid conditions and carbon dioxide properties, which are not uniform but variable within sedimentary basins. To overcome this limit of the conventional method, a new method, which can consider such spatially variable distributions of fluid conditions and carbon dioxide properties within sedimentary basins, is suggested and applied in this study. In this new method, a three-dimensional geologic formation model of a target sedimentary basin is first established and discretized into volume elements. The fluid conditions (i.e., pressure, temperature, and salt concentration) within each element are then obtained by performing thermo-hydrological numerical modeling. The carbon dioxide properties (i.e., phase, density, dynamic viscosity, and solubility to groundwater) within each element are then calculated from thermodynamic database under corresponding fluid conditions. Finally, the geologic storage capacity of carbon dioxide with in each element is estimated using the corresponding carbon dioxide properties as well as porosity and element volume, and that within the whole sedimentary basin is determined by summation over all elements. This new method is applied to the Bukpyeong Basin, which is one of the prospective offshore sedimentary basins for geologic storage of carbon dioxide in Korea. A three-dimensional geologic formation model of the Bukpyeong Basin is first established considering the elevation data of the boundaries between the geologic formations obtained from