WorldWideScience

Sample records for cgd ranks co2

  1. CGD 318 ASHFORD Course TutorialRank

    OpenAIRE

    makenz

    2015-01-01

    For more course tutorials visit www.tutorialrank.com Tutorial Purchased: 4 Times, Rating: A+   ASHFORD CGD 318 Week 1 DQ 1 What is Public Relations ASHFORD CGD 318 Week 1 DQ 2 Public Relations and Crisis Management ASHFORD CGD 318 Week 1 Quiz ASHFORD CGD 318 Week 2 DQ 1 Public Relations Research ASHFORD CGD 318 Week 2 DQ 2 Publics & Public Opinion ASHFORD CGD 318 Week 2 Assignment To Accept or Reject a Client ASHFORD CGD 318 Week 2 Quiz ASH...

  2. CGD 218 ASHFORD Course Tutorial/TutorialRank

    OpenAIRE

    makenz

    2015-01-01

    For more course tutorials visit www.tutorialrank.com Tutorial Purchased: 4 Times, Rating: A+   CGD 218 Week 1 Assignment Why is Visual Literacy Important CGD 218 Week 1 Journal The Evolution of Media CGD 218 Week 1 DQ 1 Using Visuals to Communicate CGD 218 Week 2 Assignment Final Project - Step Two CGD 218 Week 2 DQ 1 Typography in Business CGD 218 Week 2 DQ 2 Bauhaus Manifesto CGD 218 Week 3 Assignment Using Photographs from the Web CGD 218 We...

  3. Magnetic properties of (Ho 1-cGd c) Co 2 compounds

    Science.gov (United States)

    Tari, A.; Keith, V.; Hwang, J. S.

    1994-02-01

    E.S.R., magnetisation and susceptibility measurements have been carried out on the series (Ho 1-cGd c)Co 2. In compounds with c≤ 0.40 we find evidence of spin reorientation. In the three most dilute compounds a g-value of about four is obtained which increases with increasing Gd content.

  4. CGD 318 Tutorials / cgd318dotcom

    OpenAIRE

    ssva

    2015-01-01

    CGD 318 Entire Course For more course tutorials visit www.cgd318.com   CGD 318 Week 1 DQ 1 What is Public Relations CGD 318 Week 1 DQ 2 Public Relations and Crisis Management CGD 318 Week 1 Quiz CGD 318 Week 2 DQ 1 Public Relations Research CGD 318 Week 2 DQ 2 Publics & Public Opinion CGD 318 Week 2 Assignment To Accept or Reject a Client

  5. CGD 218 Tutorials / cgd218dotcom

    OpenAIRE

    nodutejakamsissss

    2015-01-01

    CGD 218 Entire Course For more course tutorials visit www.cgd218.com   CGD 218 Week 1 Assignment Why is Visual Literacy Important CGD 218 Week 1 Journal The Evolution of Media CGD 218 Week 1 DQ 1 Using Visuals to Communicate CGD 218 Week 2 Assignment Final Project - Step Two CGD 218 Week 2 DQ 1 Typography in Business CGD 218 Week 2 DQ 2 Bauhaus Manifesto CGD 218 Week 3 Assignment Using Photographs from the Web CGD 218 Week 3 Journal Visual Comm...

  6. Chronic Granulomatous Disease (CGD)

    Science.gov (United States)

    ... Share this: Main Content Area Chronic Granulomatous Disease (CGD) Phagocyte (purple) engulfing Staphylococcus aureus bacteria (yellow). Credit: NIAID CGD is a genetic disorder in which white blood ...

  7. CO2 Sequestration Potential of Texas Low-Rank Coals

    Energy Technology Data Exchange (ETDEWEB)

    Duane McVay; Walter Ayers, Jr.; Jerry Jensen; Jorge Garduno; Gonzola Hernandez; Rasheed Bello; Rahila Ramazanova

    2006-08-31

    Injection of CO{sub 2} in coalbeds is a plausible method of reducing atmospheric emissions of CO{sub 2}, and it can have the additional benefit of enhancing methane recovery from coal. Most previous studies have evaluated the merits of CO{sub 2} disposal in high-rank coals. The objective of this research was to determine the technical and economic feasibility of CO{sub 2} sequestration in, and enhanced coalbed methane (ECBM) recovery from, low-rank coals in the Texas Gulf Coast area. Our research included an extensive coal characterization program, including acquisition and analysis of coal core samples and well transient test data. We conducted deterministic and probabilistic reservoir simulation and economic studies to evaluate the effects of injectant fluid composition (pure CO{sub 2} and flue gas), well spacing, injection rate, and dewatering on CO{sub 2} sequestration and ECBM recovery in low-rank coals of the Calvert Bluff formation of the Texas Wilcox Group. Shallow and deep Calvert Bluff coals occur in two, distinct, coalbed gas petroleum systems that are separated by a transition zone. Calvert Bluff coals < 3,500 ft deep are part of a biogenic coalbed gas system. They have low gas content and are part of a freshwater aquifer. In contrast, Wilcox coals deeper than 3,500 ft are part of a thermogenic coalbed gas system. They have high gas content and are part of a saline aquifer. CO{sub 2} sequestration and ECBM projects in Calvert Bluff low-rank coals of East-Central Texas must be located in the deeper, unmineable coals, because shallow Wilcox coals are part of a protected freshwater aquifer. Probabilistic simulation of 100% CO{sub 2} injection into 20 feet of Calvert Bluff coal in an 80-acre 5-spot pattern indicates that these coals can store 1.27 to 2.25 Bcf of CO{sub 2} at depths of 6,200 ft, with an ECBM recovery of 0.48 to 0.85 Bcf. Simulation results of flue gas injection (87% N{sub 2}-13% CO{sub 2}) indicate that these same coals can store 0.34 to 0

  8. CO2 Sequestration Potential of Texas Low-Rank Coals

    Energy Technology Data Exchange (ETDEWEB)

    Duane A. McVay; Walter B. Ayers Jr; Jerry L. Jensen

    2003-07-01

    The objective of this project is to evaluate the feasibility of carbon dioxide (CO{sub 2}) sequestration in Texas low-rank coals and to determine the potential for enhanced coalbed methane (CBM) recovery as an added benefit of sequestration. The main objectives for this reporting period were to further characterize the three areas selected as potential test sites, to begin assessing regional attributes of natural coal fractures (cleats), which control coalbed permeability, and to interview laboratories for coal sample testing. An additional objective was to initiate discussions with an operating company that has interests in Texas coalbed gas production and CO{sub 2} sequestration potential, to determine their interest in participation and cost sharing in this project. Well-log data are critical for defining depth, thickness, number, and grouping of coal seams at the proposed sequestration sites. Therefore, we purchased 15 well logs from a commercial source to make coal-occurrence maps and cross sections. Log suites included gamma ray (GR), self potential (SP), resistivity, sonic, and density curves. Other properties of the coals in the selected areas were collected from published literature. To assess cleat properties and describe coal characteristics, we made field trips to a Jackson coal outcrop and visited Wilcox coal exposures at the Sandow surface mine. Coal samples at the Sandow mine were collected for CO{sub 2} and methane sorption analyses. We contacted several laboratories that specialize in analyzing coals and selected a laboratory, submitting the Sandow Wilcox coals for analysis. To address the issue of cost sharing, we had fruitful initial discussions with a petroleum corporation in Houston. We reviewed the objectives and status of this project, discussed data that they have already collected, and explored the potential for cooperative data acquisition and exchange in the future. We are pursuing a cooperative agreement with them.

  9. CGD 318 ASH Course Tutorial / cgd318dotcom

    OpenAIRE

    vasanthi05

    2015-01-01

    CGD 318 Entire Course For more course tutorials visit www.cgd318.com   CGD 318 Week 1 DQ 1 What is Public Relations CGD 318 Week 1 DQ 2 Public Relations and Crisis Management CGD 318 Week 1 Quiz CGD 318 Week 2 DQ 1 Public Relations Research CGD 318 Week 2 DQ 2 Publics & Public Opinion CGD 318 Week 2 Assignment To Accept or Reject a Client CGD 318 Week 2 Quiz CGD 318 Week 3 DQ 1 The Audience CGD 318 Week 3 DQ 2 Public Relations Tactics ...

  10. CGD 218 COURSE TUTORIAL/ snaptutorial

    OpenAIRE

    mounish

    2015-01-01

    For more classes visit www.snaptutorial.com CGD 218 Week 1 Assignment Why is Visual Literacy Important CGD 218 Week 1 Journal The Evolution of Media   CGD 218 Week 1 DQ 1 Using Visuals to Communicate   CGD 218 Week 2 Assignment Final Project - Step Two   CGD 218 Week 2 DQ 1 Typography in Business   CGD 218 Week 2 DQ 2 Bauhaus Manifesto   CGD 218 Week 3 Assignment Using Photographs from the Web   CGD 218 ...

  11. CGD 218 ASH Course Tutorial / cgd218dotcom

    OpenAIRE

    vasanthi05

    2015-01-01

    CGD 218 Entire Course For more course tutorials visit www.cgd218.com   CGD 218 Week 1 Assignment Why is Visual Literacy Important CGD 218 Week 1 Journal The Evolution of Media CGD 218 Week 1 DQ 1 Using Visuals to Communicate CGD 218 Week 2 Assignment Final Project - Step Two CGD 218 Week 2 DQ 1 Typography in Business CGD 218 Week 2 DQ 2 Bauhaus Manifesto CGD 218 Week 3 Assignment Using Photographs from the Web CGD 218 Week 3 Journal Visual Comm...

  12. CGD 318 COURSE TUTORIAL/ snaptutorial

    OpenAIRE

    mounesh

    2015-01-01

    For more classes visit www.snaptutorial.com CGD 318 Week 1 DQ 1 What is Public Relations CGD 318 Week 1 DQ 2 Public Relations and Crisis Management CGD 318 Week 1 Quiz CGD 318 Week 2 DQ 1 Public Relations Research CGD 318 Week 2 DQ 2 Publics & Public Opinion CGD 318 Week 2 Assignment To Accept or Reject a Client CGD 318 Week 2 Quiz CGD 318 Week 3 DQ 1 The Audience CGD 318 Week 3 DQ 2 Public Relations Tactics CGD 318 Week 3 Assignment News Releas...

  13. CGD 218 ash course tutorial / uophelp

    OpenAIRE

    uophelp

    2015-01-01

    For more course tutorials visit www.uophelp.com CGD 218 Week 1 Assignment Why is Visual Literacy Important CGD 218 Week 1 Journal The Evolution of Media   CGD 218 Week 1 DQ 1 Using Visuals to Communicate   CGD 218 Week 2 Assignment Final Project - Step Two   CGD 218 Week 2 DQ 1 Typography in Business   CGD 218 Week 2 DQ 2 Bauhaus Manifesto   CGD 218 Week 3 Assignment Using Photographs from the Web   CGD ...

  14. CGD 318 ASH COURSES TUTORIAL/UOPHELP

    OpenAIRE

    HACKEY

    2015-01-01

    For more course tutorials visit www.uophelp.com   CGD 318 Week 1 DQ 1 What is Public Relations CGD 318 Week 1 DQ 2 Public Relations and Crisis Management CGD 318 Week 1 Quiz CGD 318 Week 2 DQ 1 Public Relations Research CGD 318 Week 2 DQ 2 Publics & Public Opinion CGD 318 Week 2 Assignment To Accept or Reject a Client CGD 318 Week 2 Quiz CGD 318 Week 3 DQ 1 The Audience CGD 318 Week 3 DQ 2 Public Relations Tactics CGD 318 Week 3 Assignm...

  15. CGD 318 Ash course tutorial / uophelp

    OpenAIRE

    uophelp

    2015-01-01

    For more course tutorials visit www.uophelp.com   CGD 318 Week 1 DQ 1 What is Public Relations CGD 318 Week 1 DQ 2 Public Relations and Crisis Management CGD 318 Week 1 Quiz CGD 318 Week 2 DQ 1 Public Relations Research CGD 318 Week 2 DQ 2 Publics & Public Opinion CGD 318 Week 2 Assignment To Accept or Reject a Client CGD 318 Week 2 Quiz CGD 318 Week 3 DQ 1 The Audience CGD 318 Week 3 DQ 2 Public Relations Tactics CGD 318 Week 3 Assignm...

  16. CGD 218 ASH COURSES TUTORIAL/UOPHELP

    OpenAIRE

    BROADY

    2015-01-01

    For more course tutorials visit www.uophelp.com       CGD 218 Week 1 Assignment Why is Visual Literacy Important CGD 218 Week 1 Journal The Evolution of Media   CGD 218 Week 1 DQ 1 Using Visuals to Communicate   CGD 218 Week 2 Assignment Final Project - Step Two   CGD 218 Week 2 DQ 1 Typography in Business   CGD 218 Week 2 DQ 2 Bauhaus Manifesto   CGD 218 Week 3 Assignment Using Photographs...

  17. Low rank coal – CO2 gasification: Experimental study, analysis of the kinetic parameters by Weibull distribution and compensation effect

    International Nuclear Information System (INIS)

    Gasification is generally considered as the most effective for low rank coal exploitation and CO2 gasification offers the advantage of upgrading an environmentally detrimental gas. Isothermal CO2 gasification tests of Greek low rank coal were performed in a tubular fixed bed reactor, to study the effect of the various reaction conditions. Greek lignite was quite reactive with CO2, resulting in high conversions even at short reaction times, while the obtained chars remained reactive after devolatilisation, as the continuous increase of conversion indicated. Conversion was very sensitive to temperature due to both pyrolysis and C–CO2 reactions, and for the granulometries studied (up to 1000 μm) the gasification rate was independent of particle size. CO2 partial pressure affected the gasification rate at low CO2 partial pressures, since the reactivity of lignite remained high (conversion ∼85% w/w daf) even for 0.25 atm CO2 partial pressure. The presence of CO retarded the reaction and the gasification rate decreased rapidly as the concentration of CO increased. The first order Volume Reaction Model (VMR) adopted was proven quite effective in describing the experimental results. Experimental results showed that the activation energy (E) varied with time, passing through a wide maximum between 10 and 15 min. The pre-exponential factor (k0) follows the behaviour of the activation energy, however, it exhibits a more sharp maximum at the same time region. The variations of the kinetic parameters with time could be attributed to the different nature of carbon atoms gasified and the changes of the number of active collisions, as the gasification reaction proceeds. As the gasification reaction advanced the Arrhenius parameters (E and k0) increased or decreased simultaneously, exhibiting a compensation effect. The probability density function (pdf) of the Weibull distribution was employed successfully to depict the variations of the kinetic parameters, E and k0.

  18. CGD 218 UOP Course Tutorial/ Tutorialrank

    OpenAIRE

    SICEN

    2015-01-01

                      For more course tutorials visit www.tutorialrank.com Tutorial Purchased: 4 Times, Rating: A+     CGD 218 Week 1 Assignment Why is Visual Literacy Important CGD 218 Week 1 Journal The Evolution of Media CGD 218 Week 1 DQ 1 Using Visuals to Communicate CGD 218 Week 2 Assignment Final Project - Step Two CGD 218 Week 2 DQ 1 Typography in Business CGD 218 Week 2 DQ 2 Bauhaus Manife...

  19. CGD 318 UOP Course Tutorial/ Tutorialrank

    OpenAIRE

    SICENK

    2015-01-01

    For more course tutorials visit www.tutorialrank.com Tutorial Purchased: 4 Times, Rating: A+     ASHFORD CGD 318 Week 1 DQ 1 What is Public Relations ASHFORD CGD 318 Week 1 DQ 2 Public Relations and Crisis Management ASHFORD CGD 318 Week 1 Quiz ASHFORD CGD 318 Week 2 DQ 1 Public Relations Research ASHFORD CGD 318 Week 2 DQ 2 Publics & Public Opinion ASHFORD CGD 318 Week 2 Assignment To Accept or Reject a Client ASHFORD CGD 318 Week 2 Q...

  20. The Candida Genome Database (CGD), a community resource for Candida albicans gene and protein information

    OpenAIRE

    Arnaud, Martha B.; Costanzo, Maria C.; Skrzypek, Marek S.; Binkley, Gail; Lane, Christopher; Miyasato, Stuart R.; SHERLOCK, Gavin

    2004-01-01

    The Candida Genome Database (CGD) is a new database that contains genomic information about the opportunistic fungal pathogen Candida albicans. CGD is a public resource for the research community that is interested in the molecular biology of this fungus. CGD curators are in the process of combing the scientific literature to collect all C.albicans gene names and aliases; to assign gene ontology terms that describe the molecular function, biological process, and subcellular localization of ea...

  1. Successful Treatment of Fungal Osteomyelitis with Voriconazole in a Patient with CGD

    OpenAIRE

    Mahsa Oaji; Setareh Mamishi; Masoud Mohammadpour; Zahra Pourpak; Nima Parvaneh

    2010-01-01

    Background:Chronic granulomatous disease (CGD) is an immunodeficiency affecting phagocytic leukocytes. Defective respiratory burst mechanism renders the affected patients to be susceptible to catalase positive microorganisms. With the great successes in antibacterial prophylaxis and therapy, fungal infections are a persistent problem. Invasive aspergillosis is the most important cause of mortality in CGD. Case Presentation: We describe a nine year-old boy with CGD who presented with aspergill...

  2. CO2 Laser Market

    Science.gov (United States)

    Simonsson, Samuel

    1989-03-01

    It gives me a great deal of pleasure to introduce our final speaker of this morning's session for two reasons: First of all, his company has been very much in the news not only in our own community but in the pages of Wall Street Journal and in the world economic press. And, secondly, we would like to welcome him to our shores. He is a temporary resident of the United States, for a few months, forsaking his home in Germany to come here and help with the start up of a new company which we believe, probably, ranks #1 as the world supplier of CO2 lasers now, through the combination of former Spectra Physics Industrial Laser Division and Rofin-Sinar GMBH. Samuel Simonsson is the Chairman of the Board of Rofin-Sinar, Inc., here in the U.S. and managing director of Rofin-Sinar GMBH. It is a pleasure to welcome him.

  3. Successful Treatment of Fungal Osteomyelitis with Voriconazole in a Patient with CGD

    Directory of Open Access Journals (Sweden)

    Masoud Mohammadpour

    2010-12-01

    Full Text Available Background:Chronic granulomatous disease (CGD is an immunodeficiency affecting phagocytic leukocytes. Defective respiratory burst mechanism renders the affected patients to be susceptible to catalase positive microorganisms. With the great successes in antibacterial prophylaxis and therapy, fungal infections are a persistent problem. Invasive aspergillosis is the most important cause of mortality in CGD. Case Presentation: We describe a nine year-old boy with CGD who presented with aspergillus induced skull osteomyelitis. He was successfully treated with voriconazole after initial failure of amphotericin B therapy.Conclusion: Currently, newer triazoles are recommended as initial therapy for invasive aspergillosis in immunodeficiency states such as CGD.

  4. Successful Treatment of Fungal Osteomyelitis with Voriconazole in a Patient with CGD

    Directory of Open Access Journals (Sweden)

    Mahsa Oaji

    2010-12-01

    Full Text Available Background:Chronic granulomatous disease (CGD is an immunodeficiency affecting phagocytic leukocytes. Defective respiratory burst mechanism renders the affected patients to be susceptible to catalase positive microorganisms. With the great successes in antibacterial prophylaxis and therapy, fungal infections are a persistent problem. Invasive aspergillosis is the most important cause of mortality in CGD. Case Presentation: We describe a nine year-old boy with CGD who presented with aspergillus induced skull osteomyelitis. He was successfully treated with voriconazole after initial failure of amphotericin B therapy. Conclusion: Currently, newer triazoles are recommended as initial therapy for invasive aspergillosis in immunodeficiency states such as CGD.

  5. Selecting CO2 Sources for CO2 Utilization by Environmental-Merit-Order Curves.

    Science.gov (United States)

    von der Assen, Niklas; Müller, Leonard J; Steingrube, Annette; Voll, Philip; Bardow, André

    2016-02-01

    Capture and utilization of CO2 as alternative carbon feedstock for fuels, chemicals, and materials aims at reducing greenhouse gas emissions and fossil resource use. For capture of CO2, a large variety of CO2 sources exists. Since they emit much more CO2 than the expected demand for CO2 utilization, the environmentally most favorable CO2 sources should be selected. For this purpose, we introduce the environmental-merit-order (EMO) curve to rank CO2 sources according to their environmental impacts over the available CO2 supply. To determine the environmental impacts of CO2 capture, compression and transport, we conducted a comprehensive literature study for the energy demands of CO2 supply, and constructed a database for CO2 sources in Europe. Mapping these CO2 sources reveals that CO2 transport distances are usually small. Thus, neglecting transport in a first step, we find that environmental impacts are minimized by capturing CO2 first from chemical plants and natural gas processing, then from paper mills, power plants, and iron and steel plants. In a second step, we computed regional EMO curves considering transport and country-specific impacts for energy supply. Building upon regional EMO curves, we identify favorable locations for CO2 utilization with lowest environmental impacts of CO2 supply, so-called CO2 oases. PMID:26752014

  6. CO2-Neutral Fuels

    Science.gov (United States)

    Goede, Adelbert; van de Sanden, Richard

    2016-06-01

    Mimicking the biogeochemical cycle of System Earth, synthetic hydrocarbon fuels are produced from recycled CO2 and H2O powered by renewable energy. Recapturing CO2 after use closes the carbon cycle, rendering the fuel cycle CO2 neutral. Non-equilibrium molecular CO2 vibrations are key to high energy efficiency.

  7. CO2 sequestration

    International Nuclear Information System (INIS)

    This document presents the summary of a conference-debate held at the Academie des Sciences (Paris, France) on the topic of CO2 sequestration. Five papers are reviewed: problems and solutions for the CO2 sequestration; observation and surveillance of reservoirs; genesis of carbonates and geological storage of CO2; CO2 sequestration in volcanic and ultra-basic rocks; CO2 sequestration, transport and geological storage: scientific and economical perspectives

  8. Restoration of NET formation by gene therapy in CGD controls aspergillosis

    OpenAIRE

    M. Bianchi; Hakkim, A; Brinkmann, V; Siler, U; Seger, R.A.; Zychlinsky, A; Reichenbach, J.

    2009-01-01

    Chronic granulomatous disease (CGD) patients have impaired nicotinamide adenine dinucleotide phosphate (NADPH) oxidase function, resulting in poor antimicrobial activity of neutrophils, including the inability to generate neutrophil extracellular traps (NETs). Invasive aspergillosis is the leading cause of death in patients with CGD; it is unclear how neutrophils control Aspergillus species in healthy persons. The aim of this study was to determine whether gene therapy restores NET formation ...

  9. CO2NNIE

    DEFF Research Database (Denmark)

    Krogh, Benjamin Bjerre; Andersen, Ove; Lewis-Kelham, Edwin;

    2015-01-01

    We propose a system for calculating the personalized annual fuel consumption and CO2 emissions from transportation. The system, named CO2NNIE, estimates the fuel consumption on the fastest route between the frequent destinations of the user. The travel time and fuel consumption estimated are based...... the actual fuel consumption (4.6% deviation on average). We conclude, that the system provides new detailed information on CO2 emissions and fuel consumption for any make and model....

  10. Wearable CO2 sensor

    OpenAIRE

    Radu, Tanja; Fay, Cormac; Lau, King-Tong; Waite, Rhys; Diamond, Dermot

    2009-01-01

    High concentrations of CO2 may develop particularly in the closed spaces during fires and can endanger the health of emergency personnel by causing serious physiological effects. The proposed prototype provides real-time continuous monitoring of CO2 in a wearable configuration sensing platform. A commercially available electrochemical CO2 sensor was selected due to its selectivity, sensitivity and low power demand. This was integrated onto an electronics platform that performed signal capture...

  11. Electrochemical CO2 reduction

    OpenAIRE

    Kriescher, Stefanie M. A.

    2015-01-01

    The atmospheric concentration of CO2 has increased significantly during the last two centuries. Since CO2 is considered to be one of the largest contributors to the greenhouse effect and is postulated to cause global warming, it is important to stabilize and/or reduce its concentration. Apart from regulations for the amount of CO2 that may be emmitted, carbon dioxide capture and storage (CCS), biological and chemical conversions are potential ways to stabilize and/or reduce the atmospheric co...

  12. CO2 blood test

    Science.gov (United States)

    Bicarbonate test; HCO3-; Carbon dioxide test; TCO2; Total CO2; CO2 test - serum ... Many medicines can interfere with blood test results. Your health care provider will tell you if you need to stop taking any medicines before you have this test. DO ...

  13. Gastrointestinal Disorders Associated with Common Variable Immune Deficiency (CVID) and Chronic Granulomatous Disease (CGD).

    Science.gov (United States)

    Uzzan, Mathieu; Ko, Huaibin M; Mehandru, Saurabh; Cunningham-Rundles, Charlotte

    2016-04-01

    Common variable immune deficiency (CVID) and chronic granulomatous disease (CGD) are two of the well-characterized primary immune deficiencies with distinct pathologic defects. While CVID is predominantly a disorder of the adaptive immune system, in CGD, innate immunity is impaired. In both syndromes, the clinical manifestations include an increased susceptibility to infections and a number of non-infectious, inflammatory conditions including systemic autoimmunity, as well as organ-specific pathology. Among the organ-associated disorders, gastrointestinal (GI) manifestations are one of the most intractable. As such, non-infectious inflammatory disorders of the GI tract are clinically challenging as they have protean manifestations, often resembling inflammatory bowel disease (IBD) or celiac disease, are notoriously difficult to treat, and hence are associated with significant morbidity and mortality. Therefore, assessing the pathogenesis and defining appropriate therapeutic approaches for GI disease in patients with CVID and CGD is imperative. PMID:26951230

  14. University Rankings

    Directory of Open Access Journals (Sweden)

    Telichenko Valeriy Ivanovich

    2014-06-01

    Full Text Available The article gives the analysis of university rankings and defines the differences in evaluation methods and indicators of world ranking agencies, presents new approaches to making global rankings. It defines the position of MGSU in Russian universities TOP-100 ranking. University rankings are not simply information, but the evaluation instrument of quality of education, initiating the improvement of ranking position. It’s important for Russian Universities claiming for higher positions in the world rankings. MGSU position in universities ranking made the University administration consider thoroughly the University positioning in the system of higher education, in the categories of education and science and among possible employers of the university graduates.

  15. CO2 chemical valorization

    International Nuclear Information System (INIS)

    Facing global warming, different technological solutions exist to tackle carbon dioxide (CO2) emissions. Some inevitable short term emissions can be captured so as to avoid direct emissions into the atmosphere. This CO2 must then be managed and geological storage seems to currently be the only way of dealing with the large volumes involved. However, this solution faces major economic profitability and societal acceptance challenges. In this context, alternative pathways consisting in using CO2 instead of storing it do exist and are generating growing interest. This study ordered by the French Environment and Energy Management Agency (ADEME), aims at taking stock of the different technologies used for the chemical conversion of CO2 in order to have a better understanding of their development potential by 2030, of the conditions in which they could be competitive and of the main actions to be implemented in France to foster their emergence. To do this, the study was broken down into two main areas of focus: The review and characterization of the main CO2 chemical conversion routes for the synthesis of basic chemical products, energy products and inert materials. This review includes a presentation of the main principles underpinning the studied routes, a preliminary assessment of their performances, advantages and drawbacks, a list of the main R and D projects underway, a focus on emblematic projects as well as a brief analysis of the markets for the main products produced. Based on these elements, 3 routes were selected from among the most promising by 2030 for an in-depth modelling and assessment of their energy, environmental and economic performances. The study shows that the processes modelled do have favorable CO2 balances (from 1 to 4 t-CO2/t-product) and effectively constitute solutions to reduce CO2 emissions, despite limited volumes of CO2 in question. Moreover, the profitability of certain solutions will remain difficult to reach, even with an energy mix

  16. CO2-strategier

    DEFF Research Database (Denmark)

    Jørgensen, Michael Søgaard

    2008-01-01

    I 2007 henvendte Lyngby-Taarbæk kommunens Agenda 21 koordinator sig til Videnskabsbutikken og spurgte om der var interesse for at samarbejde om CO2-strategier. Da Videnskabsbutikken DTU er en åben dør til DTU for borgerne og deres organisationer, foreslog Videnskabsbutikken DTU at Danmarks...... Naturfredningsforening’s lokalkomité for Lyngby blev en del af samarbejdet for at få borgerne i kommunen involveret i arbejdet med at udvikle strategier for reduktion af CO2. Siden sommeren 2007 har Videnskabsbutikken DTU, Lyngby-Taarbæk kommune og Danmarks Naturfredningsforening i Lyngby-Taarbæk samarbejdet om analyse...... og innovation i forhold til CO2-strategier....

  17. Capnography: monitoring CO2.

    Science.gov (United States)

    Casey, Georgina

    2015-10-01

    MONITORING RESPIRATORY and metabolic function by using capnography to measure end tidal carbon dioxide is standard practice in anaesthesia. It is also becoming more common in intensive care units and during procedural sedation. End tidal carbon dioxide (EtCO2) monitoring may also be used to assess effectiveness of cardiopulmonary resuscitation. Capnography is now emerging in general medical and surgical wards to monitor respiratory depression in patients using opioid analgesics. Using EtCO2 to monitor respiratory function offers many benefits over pulse oximetry. It is important to understand the differences between these two monitoring methods, and why capnography is increasingly favoured in many situations. An understanding of the physiological processes involved in CO2 excretion allows nurses to use capnography in a safe and meaningful way, while monitoring at-risk patients in acute care. PMID:26638570

  18. CO2 emissions vs. CO2 responsibility: An input-output approach for the Turkish economy

    International Nuclear Information System (INIS)

    Recently, global warming (greenhouse effect) and its effects have become one of the hottest topics in the world agenda. There have been several international attempts to reduce the negative effects of global warming. The Kyoto Protocol can be cited as the most important agreement which tries to limit the countries' emissions within a time horizon. For this reason, it becomes important to calculate the greenhouse gas emissions of countries. The aim of this study is to estimate the amount of CO2-the most important greenhouse gas-emissions, for the Turkish economy. An extended input-output model is estimated by using 1996 data in order to identify the sources of CO2 emissions and to discuss the share of sectors in total emission. Besides, 'CO2 responsibility', which takes into account the CO2 content of imports, is estimated for the Turkish economy. The sectoral CO2 emissions and CO2 responsibilities are compared and these two notions are linked to foreign trade volume. One of the main conclusions is that the manufacturing industry has the first place in both of the rankings for CO2 emissions and CO2 responsibilities, while agriculture and husbandry has the last place

  19. CO2-neutral fuels

    Science.gov (United States)

    Goede, A. P. H.

    2015-08-01

    The need for storage of renewable energy (RE) generated by photovoltaic, concentrated solar and wind arises from the fact that supply and demand are ill-matched both geographically and temporarily. This already causes problems of overcapacity and grid congestion in countries where the fraction of RE exceeds the 20% level. A system approach is needed, which focusses not only on the energy source, but includes conversion, storage, transport, distribution, use and, last but not least, the recycling of waste. Furthermore, there is a need for more flexibility in the energy system, rather than relying on electrification, integration with other energy systems, for example the gas network, would yield a system less vulnerable to failure and better adapted to requirements. For example, long-term large-scale storage of electrical energy is limited by capacity, yet needed to cover weekly to seasonal demand. This limitation can be overcome by coupling the electricity net to the gas system, considering the fact that the Dutch gas network alone has a storage capacity of 552 TWh, sufficient to cover the entire EU energy demand for over a month. This lecture explores energy storage in chemicals bonds. The focus is on chemicals other than hydrogen, taking advantage of the higher volumetric energy density of hydrocarbons, in this case methane, which has an approximate 3.5 times higher volumetric energy density. More importantly, it allows the ready use of existing gas infrastructure for energy storage, transport and distribution. Intermittent wind electricity generated is converted into synthetic methane, the Power to Gas (P2G) scheme, by splitting feedstock CO2 and H2O into synthesis gas, a mixture of CO and H2. Syngas plays a central role in the synthesis of a range of hydrocarbon products, including methane, diesel and dimethyl ether. The splitting is accomplished by innovative means; plasmolysis and high-temperature solid oxygen electrolysis. A CO2-neutral fuel cycle is

  20. CO2-neutral fuels

    Directory of Open Access Journals (Sweden)

    Goede A. P. H.

    2015-01-01

    Full Text Available The need for storage of renewable energy (RE generated by photovoltaic, concentrated solar and wind arises from the fact that supply and demand are ill-matched both geographically and temporarily. This already causes problems of overcapacity and grid congestion in countries where the fraction of RE exceeds the 20% level. A system approach is needed, which focusses not only on the energy source, but includes conversion, storage, transport, distribution, use and, last but not least, the recycling of waste. Furthermore, there is a need for more flexibility in the energy system, rather than relying on electrification, integration with other energy systems, for example the gas network, would yield a system less vulnerable to failure and better adapted to requirements. For example, long-term large-scale storage of electrical energy is limited by capacity, yet needed to cover weekly to seasonal demand. This limitation can be overcome by coupling the electricity net to the gas system, considering the fact that the Dutch gas network alone has a storage capacity of 552 TWh, sufficient to cover the entire EU energy demand for over a month. This lecture explores energy storage in chemicals bonds. The focus is on chemicals other than hydrogen, taking advantage of the higher volumetric energy density of hydrocarbons, in this case methane, which has an approximate 3.5 times higher volumetric energy density. More importantly, it allows the ready use of existing gas infrastructure for energy storage, transport and distribution. Intermittent wind electricity generated is converted into synthetic methane, the Power to Gas (P2G scheme, by splitting feedstock CO2 and H2O into synthesis gas, a mixture of CO and H2. Syngas plays a central role in the synthesis of a range of hydrocarbon products, including methane, diesel and dimethyl ether. The splitting is accomplished by innovative means; plasmolysis and high-temperature solid oxygen electrolysis. A CO2-neutral fuel

  1. Investigation on the Dielectric Properties of CO2 and CO2-Based Gases Based on the Boltzmann Equation Analysis

    Science.gov (United States)

    Sun, Hao; Wu, Yi; Rong, Mingzhe; Guo, Anxiang; Han, Guiquan; Lu, Yanhui

    2016-03-01

    In this paper, the dielectric properties of CO2, CO2/air, CO2/O2, CO2/N2, CO2/CF4, CO2/CH4, CO2/He, CO2/H2, CO2/NH3 and CO2/CO were investigated based on the Boltzmann equation analysis, in which the reduced critical electric field strength (E/N)cr of the gases was derived from the calculated electron energy distribution function (EEDF) by solving the Boltzmann transport equation. In this work, it should be noted that the fundamental data were carefully selected by the published experimental results and calculations to ensure the validity of the calculation. The results indicate that if He, H2, N2 and CH4, in which there are high ionization coefficients or a lack of attachment reactions, are added into CO2, the dielectric properties will decrease. On the other hand, air, O2, NH3 and CF4 (ranked in terms of (E/N)cr value in increasing order) have the potential to improve the dielectric property of CO2 at room temperature. supported in part by the National Key Basic Research Program of China (973 Program) (No. 2015CB251002), the Science and Technology Project Funds of the Grid State Corporation of China (No. SGSNK00KJJS1501564), National Natural Science Foundation of China (Nos. 51221005, 51577145), the Fundamental Research Funds for the Central Universities of China, and the Program for New Century Excellent Talents in University, China

  2. Expression of the X-CGD gene during induced differentiation of myeloid leukemia cell line HL-60.

    OpenAIRE

    Barker, K A; Orkin, S H; Newburger, P E

    1988-01-01

    The expression of the X-CGD gene, which encodes the heavy-chain subunit of the phagocyte cytochrome b, was studied during induced myeloid differentiation of HL-60 cells. Incubation of the cells with a combined regimen of retinoic acid and dimethyl formamide resulted in granulocytic morphological differentiation and acquisition of nitroblue tetrazolium reduction, a measure of superoxide generation. During the 5-day course of induced differentiation, the levels of X-CGD mRNA transcripts rose 13...

  3. CO2 laser development

    International Nuclear Information System (INIS)

    The research and development programs on high-energy, short-pulse CO2 lasers were begun at LASL in 1969. Three large systems are now either operating or are being installed. The Single-Beam System (SBS), a four-stage prototype, was designed in 1971 and has been in operation since 1973 with an output energy of 250 J in a 1-ns pulse with an on-target intensity of 3.5 x 1014 W/cm2. The Dual-Beam System (DBS), now in the final stages of electrical and optical checkout, will provide about ten times more power for two-beam target irradiation experiments. Four such dual-beam modules are being installed in the Laser-Fusion Laboratory to provide an Eight-Beam System (EBS) scheduled for operation at the 5- to 10-TW level in 1977. A fourth system, a 100- to 200-TW CO2 laser, is being designed for the High-Energy Gas Laser Facility (HEGLF) program

  4. CO2 hydrogenation to methanol

    OpenAIRE

    Frilund, Christian

    2016-01-01

    The literature survey discusses the recent developments in heterogeneous catalytic hydrogenation of CO2 to methanol. Special focus was given to new coated catalysts and reactors. Methanol is an important chemical that is currently produced from synthesis gas. Methanol can also be produced from CO2, but the reaction is less thermodynamically favoured. The main reaction is the exothermic CO2 hydrogenation, and there is a competing fast reaction, the reverse water-gas shift, which converts CO2 t...

  5. Ranking scientists

    CERN Document Server

    Dorogovtsev, S N

    2015-01-01

    Currently the ranking of scientists is based on the $h$-index, which is widely perceived as an imprecise and simplistic though still useful metric. We find that the $h$-index actually favours modestly performing researchers and propose a simple criterion for proper ranking.

  6. Ar + CO2 and He + CO2 Plasmas in ASTRAL

    Science.gov (United States)

    Boivin, R. F.; Gardner, A.; Munoz, J.; Kamar, O.; Loch, S.

    2007-11-01

    Spectroscopy study of the ASTRAL helicon plasma source running Ar + CO2 and He + CO2 gas mixes is presented. ASTRAL produces plasmas with the following parameters: ne = 10^10 - 10^13 cm-3, Te = 2 - 10 eV and Ti = 0.03 - 0.5 eV, B-field <= 1.3 kGauss, rf power <= 2 kWatt. A 0.33 m scanning monochromator is used for this study. Using Ar + CO2 gas mixes, very different plasmas are observed as the concentration of CO2 is changed. At low CO2 concentration, the bluish plasma is essentially atomic and argon transitions dominate the spectra. Weak C I and O I lines are present in the 750 - 1000 nm range. At higher CO2 concentration, the plasma becomes essentially molecular and is characterized by intense, white plasma columns. Here, spectra are filled with molecular bands (CO2, CO2^+, CO and CO^+). Limited molecular dissociative excitation processes associated with the production of C I and O I emission are also observed. On the other hand, He + CO2 plasmas are different. Here, rf matches are only possible at low CO2 concentration. Under these conditions, the spectra are characterized by strong C I and O I transitions with little or no molecular bands. Strong dissociative processes observed in these plasmas can be link to the high Te associated with He plasmas. An analysis of the spectra with possible scientific and industrial applications will be presented.

  7. A internacionalização bancária – destino Brasil: o caso CGD

    OpenAIRE

    Ribeiro, Clara Maria Silva

    2011-01-01

    Este documento teve como objectivo analisar o processo de internacionalização, da Caixa Geral de Depósitos (CGD) para o Brasil. Concretizamos a tese através de um estudo qualitativo, suportado por um referencial teórico. A revisão da literatura centrou-se na Teoria Eclética e na Teoria da Internalização. O estudo em causa analisa o processo de internacionalização de um banco, sugerindo que esse processo é levado a cabo quando se pretendem reunir sinergias com os seus clie...

  8. Magnetic and electron spin resonance studies of (Ce 1-cGd c)Rh 2

    Science.gov (United States)

    Tari, A.

    1990-08-01

    Magnetic and ESR measurements have been performed on several samples of the (Ce 1-cGd c)Rh 2 series in the interval 0 ≦ c ≦ 1. It is found that only those Ce atoms with at least 3nn Gd atoms are magnetic. The cerium sublattice appears to reach the magnetic percolation limit at about c=0.3. Using the lattice parameters and the RKKY model a value of 0.19eV is computed for the effective exchange integral Jo at the GdRh 2 end of the series.

  9. Forecasting global atmospheric CO2

    Directory of Open Access Journals (Sweden)

    A. Agustí-Panareda

    2014-05-01

    Full Text Available A new global atmospheric carbon dioxide (CO2 real-time forecast is now available as part of the pre-operational Monitoring of Atmospheric Composition and Climate – Interim Implementation (MACC-II service using the infrastructure of the European Centre for Medium-Range Weather Forecasts (ECMWF Integrated Forecasting System (IFS. One of the strengths of the CO2 forecasting system is that the land surface, including vegetation CO2 fluxes, is modelled online within the IFS. Other CO2 fluxes are prescribed from inventories and from off-line statistical and physical models. The CO2 forecast also benefits from the transport modelling from a state-of-the-art numerical weather prediction (NWP system initialized daily with a wealth of meteorological observations. This paper describes the capability of the forecast in modelling the variability of CO2 on different temporal and spatial scales compared to observations. The modulation of the amplitude of the CO2 diurnal cycle by near-surface winds and boundary layer height is generally well represented in the forecast. The CO2 forecast also has high skill in simulating day-to-day synoptic variability. In the atmospheric boundary layer, this skill is significantly enhanced by modelling the day-to-day variability of the CO2 fluxes from vegetation compared to using equivalent monthly mean fluxes with a diurnal cycle. However, biases in the modelled CO2 fluxes also lead to accumulating errors in the CO2 forecast. These biases vary with season with an underestimation of the amplitude of the seasonal cycle both for the CO2 fluxes compared to total optimized fluxes and the atmospheric CO2 compared to observations. The largest biases in the atmospheric CO2 forecast are found in spring, corresponding to the onset of the growing season in the Northern Hemisphere. In the future, the forecast will be re-initialized regularly with atmospheric CO2 analyses based on the assimilation of CO2 satellite retrievals, as they

  10. Spectral Ranking

    CERN Document Server

    Vigna, Sebastiano

    2009-01-01

    This note tries to attempt a sketch of the history of spectral ranking, a general umbrella name for techniques that apply the theory of linear maps (in particular, eigenvalues and eigenvectors) to matrices that do not represent geometric transformations, but rather some kind of relationship between entities. Albeit recently made famous by the ample press coverage of Google's PageRank algorithm, spectral ranking was devised more than fifty years ago, almost exactly in the same terms, and has been studied in psychology and social sciences. I will try to describe it in precise and modern mathematical terms, highlighting along the way the contributions given by previous scholars.

  11. CO2 as a refrigerant

    CERN Document Server

    2014-01-01

    A first edition, the IIR guide “CO2 as a Refrigerant” highlights the application of carbon dioxide in supermarkets, industrial freezers, refrigerated transport, and cold stores as well as ice rinks, chillers, air conditioning systems, data centers and heat pumps. This guide is for design and development engineers needing instruction and inspiration as well as non-technical experts seeking background information on a specific topic. Written by Dr A.B. Pearson, a well-known expert in the field who has considerable experience in the use of CO2 as a refrigerant. Main topics: Thermophysical properties of CO2 – Exposure to CO2, safety precautions – CO2 Plant Design – CO2 applications – Future prospects – Standards and regulations – Bibliography.

  12. Sensitivity Analysis for Atmospheric Infrared Sounder (AIRS) CO2 Retrieval

    Science.gov (United States)

    Gat, Ilana

    2012-01-01

    The Atmospheric Infrared Sounder (AIRS) is a thermal infrared sensor able to retrieve the daily atmospheric state globally for clear as well as partially cloudy field-of-views. The AIRS spectrometer has 2378 channels sensing from 15.4 micrometers to 3.7 micrometers, of which a small subset in the 15 micrometers region has been selected, to date, for CO2 retrieval. To improve upon the current retrieval method, we extended the retrieval calculations to include a prior estimate component and developed a channel ranking system to optimize the channels and number of channels used. The channel ranking system uses a mathematical formalism to rapidly process and assess the retrieval potential of large numbers of channels. Implementing this system, we identifed a larger optimized subset of AIRS channels that can decrease retrieval errors and minimize the overall sensitivity to other iridescent contributors, such as water vapor, ozone, and atmospheric temperature. This methodology selects channels globally by accounting for the latitudinal, longitudinal, and seasonal dependencies of the subset. The new methodology increases accuracy in AIRS CO2 as well as other retrievals and enables the extension of retrieved CO2 vertical profiles to altitudes ranging from the lower troposphere to upper stratosphere. The extended retrieval method for CO2 vertical profile estimation using a maximum-likelihood estimation method. We use model data to demonstrate the beneficial impact of the extended retrieval method using the new channel ranking system on CO2 retrieval.

  13. The sequestration of CO2

    International Nuclear Information System (INIS)

    The reduction of greenhouse gas emissions, especially CO2, represents a major technological and societal challenge in the fight against climate change. Among the measures likely to reduce anthropic CO2 emissions, capture and geological storage holds out promise for the future. (author)

  14. CO2 pragmatic business solutions

    International Nuclear Information System (INIS)

    Alberta's strategy to manage the risk of climate change includes carbon dioxide (CO2) management as a mechanism to reduce greenhouse gas (GHG) emissions. The province is a leader in crude oil, bitumen and natural gas production, and as such, has seen an increase in production of CO2 and GHGs. There is a strong interest in the province to develop a CO2 market in Alberta. Stakeholders at a recent workshop suggested that projects for value-added use of CO2 be established as soon as possible. The nine suggested demonstration projects reflected the following 4 major markets for CO2: (1) enhanced oil recovery through carbon dioxide flooding, (2) enhanced coalbed methane production, (3) pressure maintenance in gas-over-bitumen projects, and (4) the recovery of solvents from hydrocarbon miscible floods. Three potential supply hubs include fertilizer producers, ethane processing, and petrochemical/gas processing plants. Most of these supply hubs will require the development of capture and processing facilities. This report briefly outlines some of the research completed in areas of CO2 capture, storage and sequestration. It also presents highlights of enhanced oil recovery demonstration projects at several oil producing areas including Swan Hills, Pembina Field, Taber Field, Acme Area, Redwater Field, Red Earth Field, Nipisi Field, Mitsue Field, and Rainbow Field. The economic implications of CO2 management were also outlined with reference to supply cost of CO2, world energy prices, long-term payouts, and costs associated with infrastructure. 32 refs. 1 tab., 13 figs

  15. CO2 Sequestration short course

    Energy Technology Data Exchange (ETDEWEB)

    DePaolo, Donald J. [Lawrence Berkeley National Laboratory; Cole, David R [The Ohio State University; Navrotsky, Alexandra [University of California-Davis; Bourg, Ian C [Lawrence Berkeley National Laboratory

    2014-12-08

    Given the public’s interest and concern over the impact of atmospheric greenhouse gases (GHGs) on global warming and related climate change patterns, the course is a timely discussion of the underlying geochemical and mineralogical processes associated with gas-water-mineral-interactions encountered during geological sequestration of CO2. The geochemical and mineralogical processes encountered in the subsurface during storage of CO2 will play an important role in facilitating the isolation of anthropogenic CO2 in the subsurface for thousands of years, thus moderating rapid increases in concentrations of atmospheric CO2 and mitigating global warming. Successful implementation of a variety of geological sequestration scenarios will be dependent on our ability to accurately predict, monitor and verify the behavior of CO2 in the subsurface. The course was proposed to and accepted by the Mineralogical Society of America (MSA) and The Geochemical Society (GS).

  16. CO2管道输送工艺技术研究%Research on CO2 Pipeline Transportation Technology

    Institute of Scientific and Technical Information of China (English)

    陆争光

    2016-01-01

    我国的 CO2排放量已居世界首位,碳减排压力巨大。为了控制温室气体的排放,CO2捕捉与封存技术呈现出快速发展的趋势,CO2管道输送相关的工艺技术也备受关注。基于纯 CO2物性以及管输CO2中杂质的种类与含量,分析了管输 CO2中的杂质会对其混合物性产生的影响规律;从管输相态选择、总体管输工艺、管输 CO2杂质预处理、设计压力和流动安全保障等方面,探讨了国内外 CO2管道输送工艺技术的发展,并对我国 CO2管道输送研究提出了相应的建议。%At present,the carbon dioxide emissions in China have been ranked first in the world,which leads to enor-mous pressure on carbon emissions.In order to control the emission of greenhouse gases,CO2 capture and geological storage technology has been developed rapidly,so also largely concern on CO2 pipeline transportation technology.Based on the pure CO2 property and the impurity,deeply analyz the effect of CO2 impurity on the property of the mixture CO2 in the pipeline. Then,introduce the current situation of CO2 pipeline transportation technology development worldwide in such aspect as phase selection,overall transportation system,impurity pretreatment,design pressure and flow assurance.Besides,analyze the problems and relative advices in CO2 pipeline transportation technology research in China.

  17. Capturing and storing CO2

    International Nuclear Information System (INIS)

    A promising way to combat global warming is to capture CO2 produced by industry and bury it in deep geologic formations. The processes are technically complex and still expensive. Before it can be captured, CO2 must be separated from other components produced by industrial processes that burn oil, gas, coal or biomass, such as nitrogen and sulfur. The CO2 is then piped down vertically from the storage facility and injected at depths of at least 800 meters. There, it reaches a 'supercritical' state in which it becomes denser and less voluminous. Three types of underground reservoirs have been tested so far: 1 - Deep onshore or offshore saline aquifers: These brackish water-bearing layers constitute the biggest reservoir, with 10,000 billion metric tons of storage capacity. They are also the most evenly distributed geographically, making it easier to find one near the source of emission. 2 - Depleted oil and gas reservoirs: injecting pressurized CO2 helps to dissolve remaining oil and reduce its viscosity. This facilitates the enhanced recovery of oil or gas from nearly depleted reservoirs, adding a potential economic advantage to the operation. The disadvantage of these reservoirs is their distance from CO2-emitting industrial sites. 3 - Unexploited coal seams: the CO2 replaces the methane that is naturally present in the coal bed. The methane can be extracted and marketed by gas companies. There are two additional solutions. The first involves storing the CO2 in carbon 'lakes' in the ocean at a minimum depth of 1,500 meters, but this has been rejected due to concerns about the impacts on the marine ecosystem and how long the CO2 would be contained. The second solution, carbon sequestration by mineral carbonation, is of more interest. Here, CO2 reacts with naturally occurring subsurface calcium and magnesium to become a carbonated rock similar to limestone, which is insoluble and therefore perfectly stable over the long term. The entire CO2 capture, compression

  18. Photocatalytic reduction of CO2

    OpenAIRE

    Torres Hurtado, Cristina

    2014-01-01

    The concentration of CO2 in the atmosphere is nowadays a worldwide problem, because is one of the gases contributing to global warming. It is a fact that CO2 is increasing every time more and more in the atmosphere due to several industrial activities and the own carbon cycle. From this point of view, it is wanted to suggest the photoreduction of CO2 in water with natural zeolites (in this case clinoptilolite) as a possible solution. In this research two different types zeolites were teste...

  19. Image reconstruction of dense scattering media from cw sources using constrained CGD and a matrix rescaling technique

    Science.gov (United States)

    Chang, Jenghwa; Graber, Harry L.; Barbour, Randall L.

    1995-05-01

    This study reports on results of our efforts to improve the efficiency and stability of previously developed reconstruction algorithms for optical diffusion tomography. The previous studies, which applied regularization and a priori contraints to iterative methods--POCS, CGD, and SART algorithms--showed that in most cases, good quality reconstructions of simply structured media were achievalbe using a perturbation model. The CGD method, which is the most efficient of the three algorithms, was, however, in some instances not able to produce good quality images because of the difficulty in applying range constraints, which can cause divergence. In this study, a scheme is proposed to detect this gradient vector is reset and the CGD reconstruction is restarted using the previous reconstruction as the initial value. In gradient vector is reset and the CGD reconstruction is restarted using the previous reconstruction as the initial value. In addition, a rescaling technique, which rescaled the weight matrix to make it more uniform and less ill-conditioned, is also used to suppress numerical errors and accelerate convergence. Two criteria, rescaling the maximum of each column to 1 and rescaling the average of each column to 1, were applied and compared to results without rescaling. The results show that, with properly imposed constraints, good quality images can be obtained using the CGD method. The convergence speed is much slower when constraints are imposed, but still comparable to the POCS and SART algorithms, The rescaling technique produces more stable and more accurate reconstructions, and speeds up the reconstruction significantly for all three algorithms.

  20. Connecting CO2. Feasibility study CO2 network Southwest Netherlands; Connecting CO2. Haalbaarheidsstudie CO2-netwerk Zuidwest-Nederland

    Energy Technology Data Exchange (ETDEWEB)

    Rutten, M.

    2009-06-10

    An overview is given of supply and demand of CO2 in the region Southwest Netherlands and the regions Antwerp and Gent in Belgium. Also attention is paid to possible connections between these regions [Dutch] Een inventarisatie wordt gegeven van vraag en aanbod van CO2 in de regio Zuidwest- Nederland en de regios Antwerpen en Gent in Belgie. Ook worden mogelijke koppelingen tussen de regios besproken.

  1. ACCURACY OF CO2 SENSORS

    OpenAIRE

    Fisk, William J.

    2008-01-01

    Are the carbon dioxide (CO2) sensors in your demand controlled ventilation systems sufficiently accurate? The data from these sensors are used to automatically modulate minimum rates of outdoor air ventilation. The goal is to keep ventilation rates at or above design requirements while adjusting the ventilation rate with changes in occupancy in order to save energy. Studies of energy savings from demand controlled ventilation and of the relationship of indoor CO2 concentrations with health...

  2. Co2 On Titan's Surface

    Science.gov (United States)

    McCord, Thomas B.; Combe, J.; Hayne, P.; Hansen, G. B.

    2007-10-01

    Evidence is reported for the presence of CO2 on the surface of Titan from the Cassini VIMS (an imaging visual and IR spectrometer) data (McCord et al., 2006, 2007). CO2 can be expected on Titan from basic planetary evolution models. It was also suggested as a plausible spectral component for bright material near the Huygens landing site (Rodriguez et al., 2006), based on structure in the 1.59-µm region. Hartung et al. (2006) searched for CO2 in one hemisphere, but they were able only to set an upper limit on the possible spatial coverage by pure CO2. Barnes et al., (2006) suggested CO2 as a possible candidate material for a 5-µm-bright region, named Tsegihi, based on the high 5-µm reflectance. However, these results are not inconsistent with our report. The evidence we report is three-fold: 1) A weak absorption near 4.9 µm in the 5-µm methane window for the Tui Regio region; 2) The spectral contrast between the 2.7- and 2.8-µm methane subwindows for the regions exhibiting the 4.9-µm absorption, with stronger absorption correlating with stronger contrast; and 3) the overall shape of the CO2 spectrum (for several grain-sizes) is consistent with the spectrum of one of the fundamental surface spectral components, as deduced by spectral mixture analysis modeling. The Tui Regio feature exhibits the strongest evidence in all three categories. Studies of this feature's morphology and albedo markings have suggested to some that it may be an active cryovolcanic feature (Barnes et al., 2006). If so, CO2 could be erupting and depositing as a frost. This likely happened elsewhere and at other times. Thus, CO2 could be a major constituent of the surface, but over time it may be mixed with other constituents, such as spectrally neutral organics raining from the atmosphere, thereby reducing the strength of its spectral signature.

  3. Study and Application of Safety Risk Evaluation Model for CO2 Geological Storage Based on Uncertainty Measure Theory

    OpenAIRE

    Hujun He; Yaning Zhao; Xingke Yang; Yaning Gao; Xu Wu

    2015-01-01

    Analyzing showed that the safety risk evaluation for CO2 geological storage had important significance. Aimed at the characteristics of CO2 geological storage safety risk evaluation, drawing on previous research results, rank and order models for safety risk evaluation of CO2 geological storage were put forward based on information entropy and uncertainty measure theory. In this model, the uncertainty problems in safety risk evaluation of CO2 geological storage were solved by qualitative anal...

  4. CO2 storage in Sweden

    International Nuclear Information System (INIS)

    This study considers options, that could be feasible for Sweden, to transport and geologically store CO2, providing that technology for electricity production with CO2 capture will be available in the future and also acceptable from cost- and reliability point of view. As a starting point, it is assumed that a new 600-1000 MW power plant, fired with coal or natural gas, will be constructed with CO2 capture and localised to the Stockholm, Malmoe or Goeteborg areas. Of vital importance for storage of carbon dioxide in a reservoir is the possibility to monitor its distribution, i.e. its migration within the reservoir. It has been shown in the SACS-project that the distribution of carbon dioxide within the reservoir can be monitored successfully, mainly by seismic methods. Suitable geologic conditions and a large storage potential seems to exist mainly in South West Scania, where additional knowledge on geology/hydrogeology has been obtained since the year 2000 in connection to geothermal energy projects, and in the Eastern part of Denmark, bordering on South West Scania. Storage of carbon dioxide from the Stockholm area should not be excluded, but more studies are needed to clarify the storage options within this area. The possibilities to use CO2 for enhanced oil recovery, EOR, in i.a. the North Sea should be investigated, in order to receive incomes from the CO2 and shared costs for infrastructure, and by this also make the CO2 regarded as a trading commodity, and thereby achieving a more favourable position concerning acceptance, legal issues and regulations. The dimensions of CO2-pipelines should be similar to those for natural natural gas, although regarding some aspects they have different design and construction prerequisites. To obtain cost efficiency, the transport distances should be kept short, and possibilities for co-ordinated networks with short distribution pipelines connected to common main pipelines, should be searched for. Also, synergies with the

  5. The CO2nnect activities

    Science.gov (United States)

    Eugenia, Marcu

    2014-05-01

    Climate change is one of the biggest challenges we face today. A first step is the understanding the problem, more exactly what is the challenge and the differences people can make. Pupils need a wide competencies to meet the challenges of sustainable development - including climate change. The CO2nnect activities are designed to support learning which can provide pupils the abilities, skills, attitudes and awareness as well as knowledge and understanding of the issues. The project "Together for a clean and healthy world" is part of "The Global Educational Campaign CO2nnect- CO2 on the way to school" and it was held in our school in the period between February and October 2009. It contained a variety of curricular and extra-curricular activities, adapted to students aged from 11 to 15. These activities aimed to develop in students the necessary skills to understanding man's active role in improving the quality of the environment, putting an end to its degrading process and to reducing the effects of climate changes caused by the human intervention in nature, including transport- a source of CO2 pollution. The activity which I propose can be easily adapted to a wide range of age groups and linked to the curricula of many subjects: - Investigate CO2 emissions from travel to school -Share the findings using an international database -Compare and discuss CO2 emissions -Submit questions to a climate- and transport expert -Partner with other schools -Meet with people in your community to discuss emissions from transport Intended learning outcomes for pupils who participate in the CO2nnect campaign are: Understanding of the interconnected mobility- and climate change issue climate change, its causes and consequences greenhouse-gas emissions from transport and mobility the interlinking of social, environmental, cultural and economic aspects of the local transport system how individual choices and participation can contribute to creating a more sustainable development

  6. Oxy-combustion of high rank coals

    OpenAIRE

    Gómez Borrego, Ángeles; Álvarez Rodríguez, Diego; Fernández Domínguez, Isabel; Ballesteros, Juan Carlos; Menéndez López, Rosa M.ª

    2007-01-01

    One of the ways to face the abatement of CO2 emissions in power plants is the combustion of coal using oxy-fuel technology. In this case coal would be burned in a O2/CO2 atmosphere and the flue gas would consist mainly of CO2 which after condensation of water could be quasy-ready for storage. Most of the work related to oxy-fuel combustion has been applied to high volatile coals. In this study run of mine and single seam coals ranging in rank from low volatile bituminous to meta-anthracite ha...

  7. A case of invasive aspergillosis in CGD patient successfully treated with Amphotericin B and INF-γ

    Directory of Open Access Journals (Sweden)

    Gerami-Shoar Mohsen

    2005-03-01

    Full Text Available Abstract Background Chronic granulomatous disease (CGD is a rare disorder of phagocytes in which absence of superoxide and hydrogen peroxide production in phagocytes predisposes patients to bacterial and fungal infections. The most common fungal infections in these patients are caused by Aspergillus species. Case presentation Here, we describe Aspergillus osteomyelitis of the ribs and hepatic abscess in a 5-year-old boy. The patient was successfully treated with Amphotericin B and INF-γ. Conclusion With respect to the high frequency of aspergillosis in the CGD patient, immune deficiency should be investigated in patients with invasive aspergillosis. Moreover, using antifungal drugs as prophylaxis can improve the quality of life in these patients.

  8. PEAT-CO2. Assessment of CO2 emissions from drained peatlands in SE Asia

    International Nuclear Information System (INIS)

    Forested tropical peatlands in SE Asia store at least 42,000 Megatonnes of soil carbon. This carbon is increasingly released to the atmosphere due to drainage and fires associated with plantation development and logging. Peatlands make up 12% of the SE Asian land area but account for 25% of current deforestation. Out of 27 million hectares of peatland, 12 million hectares (45%) are currently deforested and mostly drained. One important crop in drained peatlands is palm oil, which is increasingly used as a biofuel in Europe. In the PEAT-CO2 project, present and future emissions from drained peatlands were quantified using the latest data on peat extent and depth, present and projected land use and water management practice, decomposition rates and fire emissions. It was found that current likely CO2 emissions caused by decomposition of drained peatlands amounts to 632 Mt/y (between 355 and 874 Mt/y). This emission will increase in coming decades unless land management practices and peatland development plans are changed, and will continue well beyond the 21st century. In addition, over 1997-2006 an estimated average of 1400 Mt/y in CO2 emissions was caused by peatland fires that are also associated with drainage and degradation. The current total peatland CO2 emission of 2000 Mt/y equals almost 8% of global emissions from fossil fuel burning. These emissions have been rapidly increasing since 1985 and will further increase unless action is taken. Over 90% of this emission originates from Indonesia, which puts the country in 3rd place (after the USA and China) in the global CO2 emission ranking. It is concluded that deforested and drained peatlands in SE Asia are a globally significant source of CO2 emissions and a major obstacle to meeting the aim of stabilizing greenhouse gas emissions, as expressed by the international community. It is therefore recommended that international action is taken to help SE Asian countries, especially Indonesia, to better conserve

  9. A case of invasive aspergillosis in CGD patient successfully treated with Amphotericin B and INF-γ

    OpenAIRE

    Gerami-Shoar Mohsen; Saadat Farshid; Zomorodian Kamiar; Mamishi Setareh; Tarazooie Bita; Siadati Seyad Ahmad

    2005-01-01

    Abstract Background Chronic granulomatous disease (CGD) is a rare disorder of phagocytes in which absence of superoxide and hydrogen peroxide production in phagocytes predisposes patients to bacterial and fungal infections. The most common fungal infections in these patients are caused by Aspergillus species. Case presentation Here, we describe Aspergillus osteomyelitis of the ribs and hepatic abscess in a 5-year-old boy. The patient was successfully treated with Amphotericin B and INF-γ. Con...

  10. Nuclear power and CO2

    International Nuclear Information System (INIS)

    Temperatures in the atmosphere have risen by nearly one degree in the twentieth century. To contain changes in global climate and their consequences, worldwide emissions of CO2 need to be curbed drastically in the future. Even if CO2 emissions are not taken into account, nuclear power has no economic disadvantages compared to fossil fuels. On the basis of an amount of money per ton of carbon emitted, nuclear power is cheaper than coal and, in most cases, also than natural gas. Actually, the worldwide CO2 problem and energy generation are part of the ongoing 'sustainability' debate. The following arguments, among others, used in the discussion show the sustainable character of nuclear power: - Comparison of the risks associated with major accidents for various sources of energy show nuclear power to be relatively free from hazard. - The introduction of fast breeders and other technical factors will make it possible to use nuclear fission as an important source of energy for many centuries. - The radiotoxicity of waste over very long periods of time can be influenced, for instance, by transmutation. The need to further develop CO2-free nuclear power has been recognized by many countries, among them Switzerland. The Generation IV International Forum (GIF) works towards developing a new generation of nuclear power plants by 2030. It will be the symbiosis of the new types of reactors with today's modern plants which finally will establish CO2-free nuclear fission as a sustainable cornerstone of energy generation worldwide. That nuclear power has this potential for further development must be acknowledged generally. (orig.)

  11. Impaired apoptotic cell clearance in CGD due to altered macrophage programming is reversed by phosphatidylserine-dependent production of IL-4

    OpenAIRE

    Fernandez-Boyanapalli, Ruby F.; Frasch, S. Courtney; McPhillips, Kathleen; Vandivier, R. William; Harry, Brian L.; Riches, David W.H.; Henson, Peter M.; Bratton, Donna L.

    2009-01-01

    Chronic granulomatous disease (CGD) is characterized by overexuberant inflammation and autoimmunity that are attributed to deficient anti-inflammatory signaling. Although regulation of these processes is complex, phosphatidylserine (PS)–dependent recognition and removal of apoptotic cells (efferocytosis) by phagocytes are potently anti-inflammatory. Since macrophage phenotype also plays a beneficial role in resolution of inflammation, we hypothesized that impaired efferocytosis in CGD due to ...

  12. Global energy / CO2 projections

    International Nuclear Information System (INIS)

    Section headings are: (1) Social and economic problems of the 21st century and the role of energy supply systems (2) Energy-environment interactions as a central point of energy research activities (3) New ways of technological progress and its impacts on energy demand and supply (4) Long-term global energy projections (5) Comparative analysis of global long-term energy / CO2 studies (6) Conclusions. The author shows that, in order to alleviate the negative impacts of energy systems on the climate, it will be necessary to undertake tremendous efforts to improve the energy use efficiency, to drastically change the primary energy mix, and, at the same time, to take action to reduce greenhouse emissions from other sources and increase the CO2 sink through enhanced reforestation. (Quittner)

  13. Fang CO2 med Aminosyrer

    DEFF Research Database (Denmark)

    Lerche, Benedicte Mai

    2010-01-01

    Med såkaldte “carbon capture-teknikker” er det muligt at rense røgen fra kulfyrede kraftværker, således at den er næsten helt fri for drivhusgassen CO2. Kunsten er at gøre processen tilstrækkeligt billig. Et lovende fangstredskab i denne proces er aminosyrer.......Med såkaldte “carbon capture-teknikker” er det muligt at rense røgen fra kulfyrede kraftværker, således at den er næsten helt fri for drivhusgassen CO2. Kunsten er at gøre processen tilstrækkeligt billig. Et lovende fangstredskab i denne proces er aminosyrer....

  14. Dolomite decomposition under CO2

    International Nuclear Information System (INIS)

    Full text.Dolomite (MgCa (CO3)2 is one of the most abundant mineral species on the surface of the planet, it occurs in sedimentary rocks. MgO, CaO and Doloma (Phase mixture of MgO and CaO, obtained from the mineral dolomite) based materials are attractive steel-making refractories because of their potential cost effectiveness and world wide abundance more recently, MgO is also used as protective layers in plasma screen manufacture ceel. The crystal structure of dolomite was determined as rhombohedral carbonates, they are layers of Mg+2 and layers of Ca+2 ions. It dissociates depending on the temperature variations according to the following reactions: MgCa (CO3)2 → MgO + CaO + 2CO2.....MgCa (CO3)2 → MgO + Ca + CaCO3 + CO2.....This latter reaction may be considered as a first step for MgO production. Differential thermal analysis (DTA) are used to control dolomite decomposition and the X-Ray Diffraction (XRD) was used to elucidate thermal decomposition of dolomite according to the reaction. That required samples were heated to specific temperature and holding times. The average particle size of used dolomite powders is 0.3 mm, as where, the heating temperature was 700 degree celsius, using various holding times (90 and 120 minutes). Under CO2 dolomite decomposed directly to CaCO3 accompanied by the formation of MgO, no evidence was offered for the MgO formation of either CaO or MgCO3, under air, simultaneous formation of CaCO3, CaO and accompanied dolomite decomposition

  15. CO2 neutral seawater desalination

    International Nuclear Information System (INIS)

    This article described the development of a seawater desalination project in Carlsbad, California, which is collocated with the Encina Power Generation Station that currently uses seawater from the Pacific Ocean for once-through cooling. The Carlsbad project is being developed as a public-private partnership between Poseidon Resources and 8 local utilities and municipalities. When completed in 2012, this project will supply 6 to 8 per cent of the drinking water in San Diego County and will be the largest seawater desalination plant in the United States. The total plant carbon footprint of the facility will depend on how much electricity is used and what sources are used to generate the electricity. It has been estimated that the total carbon footprint for the Carlsbad project is 61,000 metric tons of carbon dioxide (CO2) per year and is based on desalination plant power use of 3.57 KWh/m3 of produced drinking water and on a greenhouse gas emission factor of 248.4 kg of CO2 per MWh of electricity used for the project. The plant will be located on a site that is occupied by an abandoned fuel storage tank. Reclaiming the land will produce a smaller imprint on the environment than if an undisturbed site were used. A rooftop photovoltaic system will be used for solar power generation. Approximately 2,100 tons of CO2 per year will be used to condition the freshwater for corrosion protection. This article reviewed the project feasibility, its environmental impact, site selection, pilot testing, and preliminary design estimate. 3 figs

  16. Alberta industrial synergy CO2 programs initiative

    International Nuclear Information System (INIS)

    The various industrial sectors within Alberta produce about 350,000 tonnes of CO2 per day. This presentation was concerned with how this large volume and high concentration of CO2 can be used in industrial and agricultural applications, because every tonne of CO2 used for such purposes is a tonne that does not end up in the atmosphere. There is a good potential for an industrial synergy between the producers and users of CO2. The Alberta Industrial Synergy CO2 Programs Initiative was established to ultimately achieve a balance between the producers of CO2 and the users of CO2 by creating ways to use the massive quantities of CO2 produced by Alberta's hydrocarbon-based economy. The Alberta CO2 Research Steering Committee was created to initiate and support CO2 programs such as: (1) CO2 use in enhanced oil recovery, (2) creation of a CO2 production inventory, (3) survey of CO2 users and potential users, (4) investigation of process issues such as power generation, oil sands and cement manufacturing, and (5) biofixation by plants, (6) other disposal options (e.g. in depleted oil and gas reservoirs, in aquifers, in tailings ponds, in coal beds). The single most important challenge was identified as 'rationalizing the formation of the necessary infrastructure'. Failing to do that will greatly impede efforts directed towards CO2 utilization

  17. Passive CO2 concentration in higher plants.

    Science.gov (United States)

    Sage, Rowan F; Khoshravesh, Roxana

    2016-06-01

    Photorespiratory limitations on C3 photosynthesis are substantial in warm, low CO2 conditions. To compensate, certain plants evolved mechanisms to actively concentrate CO2 around Rubisco using ATP-supported CO2 pumps such as C4 photosynthesis. Plants can also passively accumulate CO2 without additional ATP expenditure by localizing the release of photorespired and respired CO2 around Rubisco that is diffusively isolated from peripheral air spaces. Passive accumulation of photorespired CO2 occurs when glycine decarboxylase is localized to vascular sheath cells in what is termed C2 photosynthesis, and through forming sheaths of chloroplasts around the periphery of mesophyll cells. The peripheral sheaths require photorespired CO2 to re-enter chloroplasts where it can be refixed. Passive accumulation of respiratory CO2 is common in organs such as stems, fruits and flowers, due to abundant heterotrophic tissues and high diffusive resistance along the organ periphery. Chloroplasts within these organs are able to exploit this high CO2 to reduce photorespiration. CO2 concentration can also be enhanced passively by channeling respired CO2 from roots and rhizomes into photosynthetic cells of stems and leaves via lacunae, aerenchyma and the xylem stream. Through passive CO2 concentration, C3 species likely improved their carbon economy and maintained fitness during episodes of low atmospheric CO2. PMID:27058940

  18. Ranking Operations Management Conferences

    OpenAIRE

    Steenhuis, Harm-Jan; Bruijn, de, P.J.A.; Gupta, Sushil; Laptaned, U.

    2007-01-01

    Several publications have appeared in the field of Operations Management which rank Operations Management related journals. Several ranking systems exist for journals based on , for example, perceived relevance and quality, citation, and author affiliation. Many academics also publish at conferences but we have not come across publications that rank conferences. Conference rankings are generally more complicated than journal rankings. Journal rankings are primarily for publishing purposes. Co...

  19. Characterization of CO2 reservoir rock in Switzerland

    Science.gov (United States)

    Fabbri, Stefano; Madonna, Claudio; Zappone, Alba

    2014-05-01

    Anthropogenic emissions of Carbon Dioxide (CO2) are one of the key drivers regarding global climate change (IPCC, 2007). Carbon Dioxide Capture and Storage (CCS) is one valuable technology to mitigate current climate change with an immediate impact. The IPCC special report on CCS predicted a potential capture range of 4.7 to 37.5 Gt of CO2 by 2050. Among several countries, Switzerland has started to investigate its potential for CO2 storage (Chevalier et al., 2010) and is currently performing research on the characterization of the most promising reservoir/seal rocks for CO2 sequestration. For Switzerland, the most feasible option is to store CO2 in saline aquifers, sealed by impermeable formations. One aquifer of regional scale in the Swiss Molasse Basin is a carbonate sequence consisting of reworked shallow marine limestones and accumulations of shell fragments. The upper part of the formation presents the most promising permeability values and storage properties. The storage potential has been estimated of 706 Mt of CO2, based on the specific ranking scheme proposed by Chevalier et al. 2010. In this study, key parameters such as porosity, permeability and acoustic velocities in compressional and shear mode have been measured in laboratory at pressures and temperatures simulating in situ conditions. Reservoir rock samples have been investigated. Permeability has been estimated before and after CO2 injection in supercritical state. The simulation of typical reservoir conditions allows us to go one step further towards a significant evaluation of the reservoir's true capacities for CO2 sequestration. It seems of major importance to notice that the permeability crucially depends on confining pressure, temperature and pore pressure conditions of the sample. Especially at in situ conditions with CO2 being at supercritical state, a substantial loss in permeability have to be taken into consideration when it comes to the calculation of potential injection rates. The

  20. Optical properties of heusler alloys Co2FeSi, Co2FeAl, Co2CrAl, and Co2CrGa

    Science.gov (United States)

    Shreder, E. I.; Svyazhin, A. D.; Belozerova, K. A.

    2013-11-01

    The results of an investigation of optical properties and the calculations of the electronic structure of Co2FeSi, Co2FeAl, Co2CrAl, and Co2CrGa Heusler alloys are presented. The main focus of our attention is the study of the spectral dependence of the real part (ɛ1) and imaginary part (ɛ2) of the dielectric constant in the range of wavelengths λ = 0.3-13 μm using the ellipsometric method. An anomalous behavior of the optical conductivity σ(ω) has been found in the infrared range in the Co2CrAl and Co2CrGa alloys, which differs substantially from that in the Co2FeSi and Co2FeAl alloys. The results obtained are discussed based on the calculations of the electronic structure.

  1. CO2 Virtual Science Data Environment API

    Data.gov (United States)

    National Aeronautics and Space Administration — The CO2 Virtual Data Environment is a comprehensive effort at bringing together the models, data, and tools necessary to perform research on atmospheric CO2.This...

  2. Have We Overestimated Saline Aquifer CO2 Storage Capacities?

    International Nuclear Information System (INIS)

    is applied to the Utsira aquifer in the North Sea. In Sections 3 and 4, we discuss possible effects that may lead to higher or lower CO2 storage efficiencies. Water production appears to be an attractive strategy in order to address regional scale pressure build up and, consequently, to increase the storage capacity. Following these quantitative applications, we recommend to evaluate the CO2 storage capacities of an aquifer, during a screening study for ranking purposes, using a pressure and compressibility formula rather than a volumetric approach, in order to avoid large overestimation of the aquifer storage capacity. Further studies are naturally required to validate the storage capacities at a qualification stage. (authors)

  3. CyclicCO2R: production of cyclic carbonates from CO2 using renewable feedstocks

    OpenAIRE

    Kimball, E; Schuurbiers, C.A.H.; Zevenbergen, J.F.; Håkonsen, S.F.; Heyn, R.; Offermans, W.; Leitner, W.; Ostapowicz, T.; Müller, T. E.; Mul, G.; North, M.; Ngomsik-Fanselow, A.F.; Sarron, E.; Sigurbjörnsson, O.; Schäffner, B.

    2013-01-01

    The consortium behind CyclicCO2R wants to kick-start the implementation of CO2 utilization technologies by converting CO2 into a high value-added product, thus providing a showcase that inspires industry to further develop technologies utilizing CO2 as a sustainable raw material and valorizing CO2 in such a way that drives the market for CO2 capture and utilization.

  4. CO2 Efflux from Cleared Mangrove Peat

    OpenAIRE

    Lovelock, Catherine E.; Roger W Ruess; Feller, Ilka C.

    2011-01-01

    BACKGROUND: CO(2) emissions from cleared mangrove areas may be substantial, increasing the costs of continued losses of these ecosystems, particularly in mangroves that have highly organic soils. METHODOLOGY/PRINCIPAL FINDINGS: We measured CO(2) efflux from mangrove soils that had been cleared for up to 20 years on the islands of Twin Cays, Belize. We also disturbed these cleared peat soils to assess what disturbance of soils after clearing may have on CO(2) efflux. CO(2) efflux from soils de...

  5. Forest succession at elevated CO2; TOPICAL

    International Nuclear Information System (INIS)

    We tested hypotheses concerning the response of forest succession to elevated CO2 in the FACTS-1 site at the Duke Forest. We quantified growth and survival of naturally recruited seedlings, tree saplings, vines, and shrubs under ambient and elevated CO2. We planted seeds and seedlings to augment sample sites. We augmented CO2 treatments with estimates of shade tolerance and nutrient limitation while controlling for soil and light effects to place CO2 treatments within the context of natural variability at the site. Results are now being analyzed and used to parameterize forest models of CO2 response

  6. Residual CO2 trapping in Indiana limestone.

    Science.gov (United States)

    El-Maghraby, Rehab M; Blunt, Martin J

    2013-01-01

    We performed core flooding experiments on Indiana limestone using the porous plate method to measure the amount of trapped CO(2) at a temperature of 50 °C and two pressures: 4.2 and 9 MPa. Brine was mixed with CO(2) for equilibration, then the mixture was circulated through a sacrificial core. Porosity and permeability tests conducted before and after 884 h of continuous core flooding confirmed negligible dissolution. A trapping curve for supercritical (sc)CO(2) in Indiana showing the relationship between the initial and residual CO(2) saturations was measured and compared with that of gaseous CO(2). The results were also compared with scCO(2) trapping in Berea sandstone at the same conditions. A scCO(2) residual trapping end point of 23.7% was observed, indicating slightly less trapping of scCO(2) in Indiana carbonates than in Berea sandstone. There is less trapping for gaseous CO(2) (end point of 18.8%). The system appears to be more water-wet under scCO(2) conditions, which is different from the trend observed in Berea; we hypothesize that this is due to the greater concentration of Ca(2+) in brine at higher pressure. Our work indicates that capillary trapping could contribute to the immobilization of CO(2) in carbonate aquifers. PMID:23167314

  7. Reduced Rank Regression

    DEFF Research Database (Denmark)

    Johansen, Søren

    2008-01-01

    The reduced rank regression model is a multivariate regression model with a coefficient matrix with reduced rank. The reduced rank regression algorithm is an estimation procedure, which estimates the reduced rank regression model. It is related to canonical correlations and involves calculating...... eigenvalues and eigenvectors. We give a number of different applications to regression and time series analysis, and show how the reduced rank regression estimator can be derived as a Gaussian maximum likelihood estimator. We briefly mention asymptotic results...

  8. Primary cutaneous γδ-T-cell lymphoma (CGD-TCL) with unilateral lower extremity swelling as first-onset symptom: a rare case report

    OpenAIRE

    Li, Duo; Huang, Lijun; Guo, Bin; Wen, Qiuyuan; Wang, Weiyuan; Luo, Jiadi; Fan, Songqing

    2014-01-01

    Primary cutaneous γδ-T-cell lymphoma (CGD-TCL) is a distinct disease entity which is an extremely rare neoplasm with poor prognosis, characterized by the γ/δ T-cell receptor expression on atypical lymphocytes. We report the case of a 42-year-old man who first presented with a swelling in the extremities and subsequent appeared subcutaneous nodule over the body. In order to clarify the diagnosis, a biopsy of subcutaneous nodule for pathology had been done. CGD-TCL was diagnosed by histopatholo...

  9. Energyless CO2 Absorption, Generation, and Fixation Using Atmospheric CO2.

    Science.gov (United States)

    Inagaki, Fuyuhiko; Okada, Yasuhiko; Matsumoto, Chiaki; Yamada, Masayuki; Nakazawa, Kenta; Mukai, Chisato

    2016-01-01

    From an economic and ecological perspective, the efficient utilization of atmospheric CO2 as a carbon resource should be a much more important goal than reducing CO2 emissions. However, no strategy to harvest CO2 using atmospheric CO2 at room temperature currently exists, which is presumably due to the extremely low concentration of CO2 in ambient air (approximately 400 ppm=0.04 vol%). We discovered that monoethanolamine (MEA) and its derivatives efficiently absorbed atmospheric CO2 without requiring an energy source. We also found that the absorbed CO2 could be easily liberated with acid. Furthermore, a novel CO2 generator enabled us to synthesize a high value-added material (i.e., 2-oxazolidinone derivatives based on the metal catalyzed CO2-fixation at room temperature) from atmospheric CO2. PMID:26596773

  10. Exogenously produced CO2 doubles the CO2 efflux from three north temperate lakes

    Science.gov (United States)

    Wilkinson, Grace M.; Buelo, Cal D.; Cole, Jonathan J.; Pace, Michael L.

    2016-03-01

    It is well established that lakes are typically sources of CO2 to the atmosphere. However, it remains unclear what portion of CO2 efflux is from endogenously processed organic carbon or from exogenously produced CO2 transported into lakes. We estimated high-frequency CO2 and O2 efflux from three north temperate lakes in summer to determine the proportion of the total CO2 efflux that was exogenously produced. Two of the lakes were amended with nutrients to experimentally enhance endogenous CO2 uptake. In the unfertilized lake, 50% of CO2 efflux was from exogenous sources and hydrology had a large influence on efflux. In the fertilized lakes, endogenous CO2 efflux was negative (into the lake) yet exogenous CO2 made the lakes net sources of CO2 to the atmosphere. Shifts in hydrologic regimes and nutrient loading have the potential to change whether small lakes act primarily as reactors or vents in the watershed.

  11. CO2 transport over complex terrain

    Science.gov (United States)

    Sun, Jielun; Burns, Sean P.; Delany, A.C.; Oncley, S.P.; Turnipseed, A.A.; Stephens, B.B.; Lenschow, D.H.; LeMone, M.A.; Monson, Russell K.; Anderson, D.E.

    2007-01-01

    CO2 transport processes relevant for estimating net ecosystem exchange (NEE) at the Niwot Ridge AmeriFlux site in the front range of the Rocky Mountains, Colorado, USA, were investigated during a pilot experiment. We found that cold, moist, and CO2-rich air was transported downslope at night and upslope in the early morning at this forest site situated on a ???5% east-facing slope. We found that CO2 advection dominated the total CO2 transport in the NEE estimate at night although there are large uncertainties because of partial cancellation of horizontal and vertical advection. The horizontal CO2 advection captured not only the CO2 loss at night, but also the CO2 uptake during daytime. We found that horizontal CO2 advection was significant even during daytime especially when turbulent mixing was not significant, such as in early morning and evening transition periods and within the canopy. Similar processes can occur anywhere regardless of whether flow is generated by orography, synoptic pressure gradients, or surface heterogeneity as long as CO2 concentration is not well mixed by turbulence. The long-term net effect of all the CO2 budget terms on estimates of NEE needs to be investigated. ?? 2007 Elsevier B.V. All rights reserved.

  12. Modeling of CO2 storage in aquifers

    International Nuclear Information System (INIS)

    Storage of CO2 in geological formations is a means of mitigating the greenhouse effect. Saline aquifers are a good alternative as storage sites due to their large volume and their common occurrence in nature. The first commercial CO2 injection project is that of the Sleipner field in the Utsira Sand aquifer (North Sea). Nevertheless, very little was known about the effectiveness of CO2 sequestration over very long periods of time. In this way, numerical modeling of CO2 injection and seismic monitoring is an important tool to understand the behavior of CO2 after injection and to make long term predictions in order to prevent CO2 leaks from the storage into the atmosphere. The description of CO2 injection into subsurface formations requires an accurate fluid-flow model. To simulate the simultaneous flow of brine and CO2 we apply the Black-Oil formulation for two phase flow in porous media, which uses the PVT data as a simplified thermodynamic model. Seismic monitoring is modeled using Biot's equations of motion describing wave propagation in fluid-saturated poroviscoelastic solids. Numerical examples of CO2 injection and time-lapse seismics using data of the Utsira formation show the capability of this methodology to monitor the migration and dispersal of CO2 after injection.

  13. Porous Organic Polymers for CO2 Capture

    KAUST Repository

    Teng, Baiyang

    2013-05-01

    Carbon dioxide (CO2) has long been regarded as the major greenhouse gas, which leads to numerous negative effects on global environment. The capture and separation of CO2 by selective adsorption using porous materials proves to be an effective way to reduce the emission of CO2 to atmosphere. Porous organic polymers (POPs) are promising candidates for this application due to their readily tunable textual properties and surface functionalities. The objective of this thesis work is to develop new POPs with high CO2 adsorption capacities and CO2/N2 selectivities for post-combustion effluent (e.g. flue gas) treatment. We will also exploit the correlation between the CO2 capture performance of POPs and their textual properties/functionalities. Chapters Two focuses on the study of a group of porous phenolic-aldehyde polymers (PPAPs) synthesized by a catalyst-free method, the CO2 capture capacities of these PPAPs exceed 2.0 mmol/g at 298 K and 1 bar, while keeping CO2/N2 selectivity of more than 30 at the same time. Chapter Three reports the gas adsorption results of different hyper-cross-linked polymers (HCPs), which indicate that heterocyclo aromatic monomers can greatly enhance polymers’ CO2/N2 selectivities, and the N-H bond is proved to the active CO2 adsorption center in the N-contained (e.g. pyrrole) HCPs, which possess the highest selectivities of more than 40 at 273 K when compared with other HCPs. Chapter Four emphasizes on the chemical modification of a new designed polymer of intrinsic microporosity (PIM) with high CO2/N2 selectivity (50 at 273 K), whose experimental repeatability and chemical stability prove excellent. In Chapter Five, we demonstrate an improvement of both CO2 capture capacity and CO2/N2 selectivity by doping alkali metal ions into azo-polymers, which leads a promising method to the design of new porous organic polymers.

  14. Extraction of stevia glycosides with CO2 + water, CO2 + ethanol, and CO2 + water + ethanol

    Directory of Open Access Journals (Sweden)

    A. Pasquel

    2000-09-01

    Full Text Available Stevia leaves are an important source of natural sugar substitute. There are some restrictions on the use of stevia extract because of its distinctive aftertaste. Some authors attribute this to soluble material other than the stevia glycosides, even though it is well known that stevia glycosides have to some extent a bitter taste. Therefore, the purpose of this work was to develop a process to obtain stevia extract of a better quality. The proposed process includes two steps: i Pretreatment of the leaves by SCFE; ii Extraction of the stevia glycosides by SCFE using CO2 as solvent and water and/or ethanol as cosolvent. The mean total yield for SCFE pretreatment was 3.0%. The yields for SCFE with cosolvent of stevia glycosides were below 0.50%, except at 120 bar, 16°C, and 9.5% (molar of water. Under this condition, total yield was 3.4%. The quality of the glycosidic fraction with respect to its capacity as sweetener was better for the SCFE extract as compared to extract obtained by the conventional process. The overall extraction curves were well described by the Lack extended model.

  15. Sustainable Process Networks for CO2 Conversion

    DEFF Research Database (Denmark)

    Frauzem, Rebecca; Kongpanna, P.; Pavarajam, V.;

    contributors to global warming, primarily greenhouse gas emissions. Of these, carbon dioxide (CO2) is the largest source and, therefore, the reduction of the amount emitted is primary focus of developments [1]. Currently, the main method that is focused on is carbon capture and storage (CCS). There are various...... drawbacks to this geologic storage system: the CO2 is not eliminated, the implementation is limited due to natural phenomena, and the capturing methods are often expensive. Thus, it is desirable to develop an alternative strategy for reducing the CO2 emissions [2]. An additional process that reduces the...... emissions is the conversion of CO2 into useful products, such as methanol [3]. In this work, through a computer-aided framework for process network synthesis-design, a network of feasible conversion processes that all use emitted CO2 is investigated. CO2 is emitted into the environment from various sources...

  16. Carbon dioxide (CO2) angiography in children

    International Nuclear Information System (INIS)

    Background. When iodinated contrast material is contraindicated, carbon dioxide (CO2) gas can be injected intravascularly to produce high-quality digital subtraction angiograms. Objective. CO2 angiography, although previously described in adults, has never before been reported in children. Materials and methods. We present three children with renal transplants who required renal angiography. Because of elevated creatinine levels, iodinated contrast was not used to search for possible renal artery stenosis. Instead, CO2 angiography was used to evaluate the renal artery anastomosis. Results. In all three cases, the renal artery anastomosis was clearly visualized using CO2 angiography and showed no evidence of renal artery stenosis. Conclusion. Digital CO2 angiography is an effective method for pediatric renal angiography. The technique can easily be adapted for virtually any angiographic laboratory capable of digital subtraction imaging. Digital CO2 angiography also lacks the risks of a conventional iodinated contrast medium, namely nephrotoxicity, allergic reaction and volume overload. (orig.). With 1 fig

  17. CO2 Capture by Cement Raw Meal

    DEFF Research Database (Denmark)

    Pathi, Sharat Kumar; Lin, Weigang; Illerup, Jytte Boll;

    2013-01-01

    The cement industry is one of the major sources of CO2 emissions and is likely to contribute to further increases in the near future. The carbonate looping process has the potential to capture CO2 emissions from the cement industry, in which raw meal for cement production could be used as the...... sorbent. Cyclic experiments were carried out in a TGA apparatus using industrial cement raw meal and synthetic raw meal as sorbents, with limestone as the reference. The results show that the CO2 capture capacities of the cement raw meal and the synthetic raw meal are comparable to those of pure limestone....... The CO2 capture capacity of limestone in the raw meal is lower than for pure limestone. The difference in the CO2 capture capacity decreases with an increase in cycle number. The calcination conditions and composition are major factors that influence the CO2 capture capacity of limestone. At 850 °C in...

  18. Advanced technology development reducing CO2 emissions

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Dong Sup

    2010-09-15

    Responding to Korean government policies on green growth and global energy/ environmental challenges, SK energy has been developing new technologies to reduce CO2 emissions by 1) CO2 capture and utilization, 2) efficiency improvement, and 3) Li-ion batteries. The paper introduces three advanced technologies developed by SK energy; GreenPol, ACO, and Li-ion battery. Contributing to company vision, a more energy and less CO2, the three technologies are characterized as follows. GreenPol utilizes CO2 as a feedstock for making polymer. Advanced Catalytic Olefin (ACO) reduces CO2 emission by 20% and increase olefin production by 17%. Li-ion Batteries for automotive industries improves CO2 emission.

  19. Near-future perspective of CO2 aquifer storage in Japan: Site selection and capacity

    International Nuclear Information System (INIS)

    Japan has started a 5-year national R and D project titled 'Underground Storage of Carbon Dioxide' to reduce CO2 emissions into the atmosphere. One of the targets of the project is to select a few preferred storage sites as candidates for large-scale demonstration tests in the next phase, and for commercial use in the near future. For this purpose, we have ranked the sites in terms of capacity potential and CO2 supply potential, both of which significantly affect the storage economics. Here, the supply potential for a storage site is characterized by the annual amount of the stationary emission sources and the site-source distance; that is, how much CO2 is available and how far away it is. In total, 69 sites on land and offshore and 113 fossil fuel fired power plants are being considered. Finally, using the data on capacities and supply potentials, the sites are graded into three ranks. As a result, a map that shows the rankings of each site has been made. The sites in rank 1 are recommended as near-future candidate sites. These sites have a comparatively large capacity and can obtain a reasonable amount of CO2 from nearby sources without requiring a main pipeline. (author)

  20. Transport and storage of CO2

    International Nuclear Information System (INIS)

    A brief overview is given of the investment cost and the operation and maintenance cost as well as the total cost of CO2 transport by pipeline (onshore) and CO2 sequestration in an onshore, depleted gas reservoir or a coal seam (CO2 Enhanced Coal Bed Methane). The costs are based on literature sources and refer to the state-of-the-art of 2004

  1. CO2 Allowance and Electricity Price Interaction

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2007-07-01

    With the introduction of CO2 emission constraints on power generators in the European Union, climate policy is starting to have notable effects on energy markets. This paper sheds light on the links between CO2 prices, electricity prices, and electricity costs to industry. It is based on a series of interviews with industrial and electricity stakeholders, as well as a rich literature seeking to estimate the exact effect of CO2 prices on electricity prices.

  2. Air reversing CO2 heat pumps

    OpenAIRE

    Andreassen, Hanne Elisabeth Bø

    2010-01-01

    CO2 is an environmentally friendly refrigerant that has a no global warming potential when used as refrigerant. The current refrigerants used for air conditioning in public transport are chemical components, and have a high global warming impact. The possibility of replacing the conventional refrigerants by CO2 is investigated for various parts of the transport sector. A possible CO2system for heating and cooling for public transport has been modeled and simulated. This system is a turntable ...

  3. On organic soil carbon and CO2

    OpenAIRE

    Bohn, Hinrich L.

    2011-01-01

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

  4. CO2 Absorbing Capacity of MEA

    OpenAIRE

    José I Huertas; Gomez, Martin D.; Nicolas Giraldo; Jessica Garzón

    2015-01-01

    We describe the use of a gas bubbler apparatus in which the gas phase is bubbled into a fixed amount of absorbent under standard conditions as a uniform procedure for determining the absorption capacity of solvents. The method was systematically applied to determine the CO2 absorbing capacity of MEA (Ac) at several aqueous MEA (β) and gas-phase CO2 concentrations. Ac approached the nominal CO2 absorbing capacity of MEA (720 g CO2/kg MEA) at very low β levels, increasing from 447.9±18.1 to 581...

  5. Primary cutaneous γδ-T-cell lymphoma (CGD-TCL) with unilateral lower extremity swelling as first-onset symptom: a rare case report.

    Science.gov (United States)

    Li, Duo; Huang, Lijun; Guo, Bin; Wen, Qiuyuan; Wang, Weiyuan; Luo, Jiadi; Fan, Songqing

    2014-01-01

    Primary cutaneous γδ-T-cell lymphoma (CGD-TCL) is a distinct disease entity which is an extremely rare neoplasm with poor prognosis, characterized by the γ/δ T-cell receptor expression on atypical lymphocytes. We report the case of a 42-year-old man who first presented with a swelling in the extremities and subsequent appeared subcutaneous nodule over the body. In order to clarify the diagnosis, a biopsy of subcutaneous nodule for pathology had been done. CGD-TCL was diagnosed by histopathology, immunophenotype, in situ hybridization and analysis of TCRγ genes rearrangement. The patient was treated with chemotherapeutic regimens-CHOP (cyclophosphamide, doxorubicin, vincristine and prednisolone). After one period of chemotherapy, subcutaneous nodules became small, even disappeared, swelling and ulcer in the left pedal gone away gradually. One month later after first chemotherapy, tumor relapsed with lesions growing back rapidly, also showed disease in double lungs. The patient was just 10-month survival time from the onset. To our knowledge, this case is the first report of CGD-TCL with unilateral lower extremity swelling as the first-onset symptom. If patient is presented the first symptoms such as swelling of extremities, especially when ulceration appears, it is of great significance to be considerate about the possibility of CGD-TCL. PMID:25197420

  6. Experimental Ion Mobility measurements in Ne-CO2 and CO2-N2 mixtures

    Science.gov (United States)

    Encarnação, P. M. C. C.; Cortez, A. F. V.; Veenhof, R.; Neves, P. N. B.; Santos, F. P.; Trindade, A. M. F.; Borges, F. I. G. M.; Conde, C. A. N.

    2016-05-01

    In this paper we present the experimental results for the mobility, K0, of ions in neon-carbon dioxide (Ne-CO2) and carbon dioxide-nitrogen (CO2-N2) gaseous mixtures for total pressures ranging from 8–12 Torr, reduced electric fields in the 10–25 Td range, at room temperature. Regarding the Ne-CO2 mixture only one peak was observed for CO2 concentrations above 25%, which has been identified as an ion originated in CO2, while below 25% of CO2 a second-small peak appears at the left side of the main peak, which has been attributed to impurities. The mobility values for the main peak range between 3.51 ± 0.05 and 1.07 ± 0.01 cm2V‑1s‑1 in the 10%-99% interval of CO2, and from 4.61 ± 0.19 to 3.00 ± 0.09 cm2V‑1s‑1 for the second peak observed (10%–25% of CO2). For the CO2-N2, the time-of-arrival spectra displayed only one peak for CO2 concentrations above 10%, which was attributed to ions originated in CO2, namely CO2+(CO2), with a second peak appearing for CO2 concentrations below 10%. This second peak, with higher mobility, was attributed to CO2+ ions. The mobility values of the main peak range between 2.11 ± 0.04 and 1.10 ± 0.03 cm2V‑1s‑1 in the 1%–99% interval of CO2, while the second peak's from 2.26 ± 0.02 and 1.95 ± 0.04 cm2V‑1s‑1 (1%–10% of CO2). The inverse of the mobility displays an aproximately linear dependence on the CO2 concentration in the mixture.

  7. Playing the Rankings Game.

    Science.gov (United States)

    Machung, Anne

    1998-01-01

    The "U.S. News and World Report" rankings of colleges do not affect institutions equally; the schools impacted most are those that have the most to lose because they benefit from, even rely on, the rankings for prestige and visibility. The magazine relies on the rankings for substantial sales revenues, and has garnered considerable power within…

  8. CAPTURING CO2 WITH MGO AEROGELS

    Science.gov (United States)

    CO2 capture from flue gas requires that the adsorbent be active at relatively low CO2 concentrations (3 – 13 vol%), high temperatures (~ 250ºC), and in the presence of many other gas species. These conditions will be simulated in the student designed reactor. The...

  9. Toxic emissions and devalued CO2-neutrality

    DEFF Research Database (Denmark)

    Czeskleba-Dupont, Rolf

    friendly effects of substituting wood burning for fossil fuels. With reference to Bent Sørensen's classical work on 'Renewable Energy' the assumption of CO2-neutrality regarding incineration is problematised when applied to plants with long rotation periods as trees. Registered CO2-emissions from wood...

  10. Charged water- and CO2-clusters

    International Nuclear Information System (INIS)

    A supersonic molecular beam source with an internal radioactive β-emitter produces a variety of unusual positively or negatively charged cluster ions, among them the so called ''hydrated'' electrons (H2O)sub(n)-, with n>=8. For a CO2-expansion the metastable ion CO2- is observed. (Auth.)

  11. Charged water- and CO2-clusters

    International Nuclear Information System (INIS)

    A supersonic molecular beam source with an internal radioactive #betta#-emitter produces a variety of unusual positively or negatively charged cluster ions, among them the so called 'hydrated' electrons (H2O)sup(-n), with n>=81. For a CO2-expansion the metastable ion CO-2 is observed. (Author)

  12. CO2 emission calculations and trends

    International Nuclear Information System (INIS)

    Evidence that the atmospheric CO2 concentration has risen during the past several decades is irrefutable. Most of the observed increase in atmospheric CO2 is believed to result from CO2 releases from fossil-fuel burning. The United Nations (UN) Framework Convention on Climate Change (FCCC), signed in Rio de Janeiro in June 1992, reflects global concern over the increasing CO2 concentration and its potential impact on climate. One of the convention's stated objectives was the ''stabilization of greenhouse gas concentrations in the atmosphere at a level that would prevent dangerous anthropogenic interference with the climate system. '' Specifically, the FCCC asked all 154 signing countries to conduct an inventory of their current greenhouse gas emissions, and it set nonbinding targets for some countries to control emissions by stabilizing them at 1990 levels by the year 2000. Given the importance of CO2 as a greenhouse gas, the relationship between CO2 emissions and increases in atmospheric CO2 levels, and the potential impacts of a greenhouse gas-induced climate change; it is important that comprehensive CO2 emissions records be compiled, maintained, updated, and documented

  13. CO2 Rekentool voor Tuinbouw: Handleiding

    NARCIS (Netherlands)

    Hiller, S.R.C.H.; Danse, M.G.

    2009-01-01

    Dit document is een handleiding bij de online CO2 Rekentool voor Tuinbouw Ketens. De CO2 tool is mogelijk gemaakt door de financiële bijdrage van Productschap Tuinbouw en het Ministerie van Landbouw, Natuur en Voedselkwaliteit (LNV). De tool is ontwikkeld door het onderzoeksconsortium WUR, BMA en AI

  14. Leaf cavity CO2 concentrations and CO2 exchange in onion, Allium cepa L.

    Science.gov (United States)

    Byrd, G T; Loboda, T; Black, C C; Brown, R H

    1995-06-01

    Onion (Allium cepa L.) plants were examined to determine the photosynthetic role of CO2 that accumulates within their leaf cavities. Leaf cavity CO2 concentrations ranged from 2250 μL L(-1) near the leaf base to below atmospheric (CO2 concentrations with minimum values near midday and maximum values at night. Conductance to CO2 from the leaf cavity ranged from 24 to 202 μmol m(-2) s(-1) and was even lower for membranes of bulb scales. The capacity for onion leaves to recycle leaf cavity CO2 was poor, only 0.2 to 2.2% of leaf photosynthesis based either on measured CO2 concentrations and conductance values or as measured directly by (14)CO2 labeling experiments. The photosynthetic responses to CO2 and O2 were measured to determine whether onion leaves exhibited a typical C3-type response. A linear increase in CO2 uptake was observed in intact leaves up to 315 μL L(-1) of external CO2 and, at this external CO2 concentration, uptake was inhibited 35.4±0.9% by 210 mL L(-1) O2 compared to 20 mL L(-1) O2. Scanning electron micrographs of the leaf cavity wall revealed degenerated tissue covered by a membrane. Onion leaf cavity membranes apparently are highly impermeable to CO2 and greatly restrict the refixation of leaf cavity CO2 by photosynthetic tissue. PMID:24307095

  15. Geophysical monitoring technology for CO2 sequestration

    Science.gov (United States)

    Ma, Jin-Feng; Li, Lin; Wang, Hao-Fan; Tan, Ming-You; Cui, Shi-Ling; Zhang, Yun-Yin; Qu, Zhi-Peng; Jia, Ling-Yun; Zhang, Shu-Hai

    2016-06-01

    Geophysical techniques play key roles in the measuring, monitoring, and verifying the safety of CO2 sequestration and in identifying the efficiency of CO2-enhanced oil recovery. Although geophysical monitoring techniques for CO2 sequestration have grown out of conventional oil and gas geophysical exploration techniques, it takes a long time to conduct geophysical monitoring, and there are many barriers and challenges. In this paper, with the initial objective of performing CO2 sequestration, we studied the geophysical tasks associated with evaluating geological storage sites and monitoring CO2 sequestration. Based on our review of the scope of geophysical monitoring techniques and our experience in domestic and international carbon capture and sequestration projects, we analyzed the inherent difficulties and our experiences in geophysical monitoring techniques, especially, with respect to 4D seismic acquisition, processing, and interpretation.

  16. Dynamics of CO2 fluxes and concentrations during a shallow subsurface CO2 release

    Energy Technology Data Exchange (ETDEWEB)

    Lewicki, J.L.; Hilley, G.E.; Dobeck, L.; Spangler, L.

    2009-09-01

    A field facility located in Bozeman, Montana provides the opportunity to test methods to detect, locate, and quantify potential CO2 leakage from geologic storage sites. From 9 July to 7 August 2008, 0.3 t CO2 d{sup -1} were injected from a 100-m long, {approx}2.5 m deep horizontal well. Repeated measurements of soil CO2 fluxes on a grid characterized the spatio-temporal evolution of the surface leakage signal and quantified the surface leakage rate. Infrared CO2 concentration sensors installed in the soil at 30 cm depth at 0 to 10 m from the well and at 4 cm above the ground at 0 and 5 m from the well recorded surface breakthrough of CO2 leakage and migration of CO2 leakage through the soil. Temporal variations in CO2 concentrations were correlated with atmospheric and soil temperature, wind speed, atmospheric pressure, rainfall, and CO2 injection rate.

  17. Investigation of oxygen-containing group promotion effect on CO2–coal interaction by density functional theory

    International Nuclear Information System (INIS)

    Highlights: • Effect of oxygen-containing groups on CO2–coal interaction has been investigated. • The forming of hydrogen bonds significantly enhances CO2 sorption capacity. • The induced HOMOs delocalization is advantageous for CO2–coal interaction. • Oxygen-containing groups induced charge distributions enhance CO2 adsorption. • Steric hindrance effect forces CO2 to adsorb on the less stable sites. - Abstract: Density functional theory including dispersion correction (DFT-D) calculations were carried out to investigate the adsorption mechanisms of CO2 on low rank coal, which had higher oxygen/carbon ratio and more surface oxygen-containing groups. Four typical oxygen-containing groups of –COOH, –CHO, –OH and –OCH3 were embedded in graphite surface as four coal models. For comparison, two original coal models of Perfect Graphite and Graphite–H were constructed. The formation of hydrogen bonds between functional groups and CO2 molecules significantly enhanced the CO2–coal interaction. The coal surface functional groups promoted the delocalization of electronic distributions and changed the highest occupied molecular orbitals (HOMOs), both of which were advantageous to CO2–coal interaction. When the effect of steric hindrance dominated the adsorption, CO2 molecules had to be forced to adsorb on less stable sites, leading to the decrease of CO2 adsorption

  18. Sparse structure regularized ranking

    KAUST Repository

    Wang, Jim Jing-Yan

    2014-04-17

    Learning ranking scores is critical for the multimedia database retrieval problem. In this paper, we propose a novel ranking score learning algorithm by exploring the sparse structure and using it to regularize ranking scores. To explore the sparse structure, we assume that each multimedia object could be represented as a sparse linear combination of all other objects, and combination coefficients are regarded as a similarity measure between objects and used to regularize their ranking scores. Moreover, we propose to learn the sparse combination coefficients and the ranking scores simultaneously. A unified objective function is constructed with regard to both the combination coefficients and the ranking scores, and is optimized by an iterative algorithm. Experiments on two multimedia database retrieval data sets demonstrate the significant improvements of the propose algorithm over state-of-the-art ranking score learning algorithms.

  19. Potential and economics of CO2 sequestration

    International Nuclear Information System (INIS)

    Increasing atmospheric level of greenhouse gases are causing global warming and putting at risk the global climate system. The main anthropogenic greenhouse gas is CO2. Some techniques could be used to reduced CO2 emission and stabilize atmospheric CO2 concentration, including i) energy savings and energy efficiency, ii) switch to lower carbon content fuels (natural gas) and use energy sources with zero CO2 emissions such as renewable or nuclear energy, iii) capture and store CO2 from fossil fuels combustion, and enhance the natural sinks for CO2 (forests, soils, ocean...). The purpose of this report is to provide an overview of the technology and cost for capture and storage of CO2 and to review the various options for CO2 sequestration by enhancing natural carbon sinks. Some of the factors which will influence application, including environmental impact, cost and efficiency, are discussed. Capturing CO2 and storing it in underground geological reservoirs appears as the best environmentally acceptable option. It can be done with existing technology, however, substantial R and D is needed to improve available technology and to lower the cost. Applicable to large CO2 emitting industrial facilities such as power plants, cement factories, steel industry, etc., which amount to about 30% of the global anthropic CO2 emission, it represents a valuable tool in the baffle against global warming. About 50% of the anthropic CO2 is being naturally absorbed by the biosphere and the ocean. The 'natural assistance' provided by these two large carbon reservoirs to the mitigation of climate change is substantial. The existing natural sinks could be enhanced by deliberate action. Given the known and likely environmental consequences, which could be very damaging indeed, enhancing ocean sinks does not appears as a satisfactory option. In contrast, the promotion of land sinks through demonstrated carbon-storing approach to agriculture, forests and land management could make a

  20. Carbonation and CO2 uptake of concrete

    International Nuclear Information System (INIS)

    This study developed a reliable procedure to assess the carbon dioxide (CO2) uptake of concrete by carbonation during the service life of a structure and by the recycling of concrete after demolition. To generalize the amount of absorbable CO2 per unit volume of concrete, the molar concentration of carbonatable constituents in hardened cement paste was simplified as a function of the unit content of cement, and the degree of hydration of the cement paste was formulated as a function of the water-to-cement ratio. The contribution of the relative humidity, type of finishing material for the concrete surface, and the substitution level of supplementary cementitious materials to the CO2 diffusion coefficient in concrete was reflected using various correction factors. The following parameters varying with the recycling scenario were also considered: the carbonatable surface area of concrete crusher-runs and underground phenomena of the decreased CO2 diffusion coefficient and increased CO2 concentration. Based on the developed procedure, a case study was conducted for an apartment building with a principal wall system and an office building with a Rahmen system, with the aim of examining the CO2 uptake of each structural element under different exposure environments during the service life and recycling of the building. As input data necessary for the case study, data collected from actual surveys conducted in 2012 in South Korea were used, which included data on the surrounding environments, lifecycle inventory database, life expectancy of structures, and recycling activity scenario. Ultimately, the CO2 uptake of concrete during a 100-year lifecycle (life expectancy of 40 years and recycling span of 60 years) was estimated to be 15.5%–17% of the CO2 emissions from concrete production, which roughly corresponds to 18%–21% of the CO2 emissions from the production of ordinary Portland cement. - Highlights: • CO2 uptake assessment approach owing to the concrete

  1. CO2 deserts: implications of existing CO2 supply limitations for carbon management.

    Science.gov (United States)

    Middleton, Richard S; Clarens, Andres F; Liu, Xiaowei; Bielicki, Jeffrey M; Levine, Jonathan S

    2014-10-01

    Efforts to mitigate the impacts of climate change will require deep reductions in anthropogenic CO2 emissions on the scale of gigatonnes per year. CO2 capture and utilization and/or storage technologies are a class of approaches that can substantially reduce CO2 emissions. Even though examples of this approach, such as CO2-enhanced oil recovery, are already being practiced on a scale >0.05 Gt/year, little attention has been focused on the supply of CO2 for these projects. Here, facility-scale data newly collected by the U.S. Environmental Protection Agency was processed to produce the first comprehensive map of CO2 sources from industrial sectors currently supplying CO2 in the United States. Collectively these sources produce 0.16 Gt/year, but the data reveal the presence of large areas without access to CO2 at an industrially relevant scale (>25 kt/year). Even though some facilities with the capability to capture CO2 are not doing so and in some regions pipeline networks are being built to link CO2 sources and sinks, much of the country exists in "CO2 deserts". A life cycle analysis of the sources reveals that the predominant source of CO2, dedicated wells, has the largest carbon footprint further confounding prospects for rational carbon management strategies. PMID:25137398

  2. CO2 Accounting and Risk Analysis for CO2 Sequestration at Enhanced Oil Recovery Sites.

    Science.gov (United States)

    Dai, Zhenxue; Viswanathan, Hari; Middleton, Richard; Pan, Feng; Ampomah, William; Yang, Changbing; Jia, Wei; Xiao, Ting; Lee, Si-Yong; McPherson, Brian; Balch, Robert; Grigg, Reid; White, Mark

    2016-07-19

    Using CO2 in enhanced oil recovery (CO2-EOR) is a promising technology for emissions management because CO2-EOR can dramatically reduce sequestration costs in the absence of emissions policies that include incentives for carbon capture and storage. This study develops a multiscale statistical framework to perform CO2 accounting and risk analysis in an EOR environment at the Farnsworth Unit (FWU), Texas. A set of geostatistical-based Monte Carlo simulations of CO2-oil/gas-water flow and transport in the Morrow formation are conducted for global sensitivity and statistical analysis of the major risk metrics: CO2/water injection/production rates, cumulative net CO2 storage, cumulative oil/gas productions, and CO2 breakthrough time. The median and confidence intervals are estimated for quantifying uncertainty ranges of the risk metrics. A response-surface-based economic model has been derived to calculate the CO2-EOR profitability for the FWU site with a current oil price, which suggests that approximately 31% of the 1000 realizations can be profitable. If government carbon-tax credits are available, or the oil price goes up or CO2 capture and operating expenses reduce, more realizations would be profitable. The results from this study provide valuable insights for understanding CO2 storage potential and the corresponding environmental and economic risks of commercial-scale CO2-sequestration in depleted reservoirs. PMID:27362472

  3. CO2 Capture for Cement Technology

    DEFF Research Database (Denmark)

    Pathi, Sharat Kumar

    , more than 80% of the inlet CO2 was captured by highly deactivated limestone, which had a maximum CO2 capture capacity of 11.5%, with an inlet Ca/C ratio of 13. So, the performance of the carbonator can be defined by the inlet Ca/C ratio, which can be estimated if the maximum capture capacity of...... carbonator. Based on the model simulation results a particle recirculation of 2-5 kg/m2s is sufficient for 90% CO2 capture efficiency depending on active fraction, inlet CO2 concentration and composition of particle stream. Based on the main experimental results, i.e. the CO2 capture capacity of raw meal as...... ppmvin 1960 to 390 ppmv in 2012, probably due to human activity. A lot of research is being carried out forreducing CO2emissions from large stationary sources. Ofwhich, the carbonate looping process is anew process and has the potential to reduce CO2emissions with lower energy penalties. Most of thework...

  4. Spin polarization effect for Co2 molecule

    Institute of Scientific and Technical Information of China (English)

    Yan Shi-Ying; Bao Wen-Sheng

    2007-01-01

    The density functional theory (DFT)(b3p86) of Gaussian 03 has been used to optimize the structure of the Co2molecule, a transition metal element molecule. The result shows that the ground state for the Co2 molecule is a 7-multiple state, indicating a spin polarization effect in the Co2 molecule. Meanwhile, we have not found any spin pollution because the wavefunction of the ground state is not mingled with wavefunctions of higher-energy states. So for the ground state of Co2 molecule to be a 7-multiple state is the indicative of spin polarization effect of the Co2molecule, that is, there exist 6 parallel spin electrons in a Co2 molecule. The number of non-conjugated electrons is the greatest. These electrons occupy different spacial orbitals so that the energy of the Co2 molecule is minimized. It can be concluded that the effect of parallel spin in the Co2 molecule is larger than the effect of the conjugated molecule,which is obviously related to the effect of electron d delocalization. In addition, the Murrell-Sorbie potential functions with the parameters for the ground state and the other states of the Co2 molecule are derived. The dissociation energy De for the ground state of Co2 molecule is 4.0489eV, equilibrium bond length Re is 0.2061 nm, and vibration frequency 11.2222 aJ.nm-4respectively(1 a.J=10-18 J). The other spectroscopic data for the ground state of Co2 molecule ωexe,Be, and αe are 0.7202 cm-1, 0.1347 cm-1, and 2.9120× 10-1 cm-1 respectively. And ωexe is the non-syntonic part of frequency, Be is the rotational constant, αe is revised constant of rotational constant for non-rigid part of Co2 molecule.

  5. Subsurface Water as Natural CO2 Sink

    International Nuclear Information System (INIS)

    In aquifer recharge areas, groundwater mineralization acts as an important sink for CO2 (assessed at 100 Mtco2/a on a European scale). An isotopic study of C fluxes in the unsaturated zone of a sand carbonate aquifer shows that the physical and geochemical processes controlling CO2 abstraction induce changes in the isotopic composition of both dissolved and matrix carbonates. An integrated record of these fluxes toward the aquifers is evidenced through isotopic investigation of the recharge areas. It is evidenced that the unsaturated zone represents an archive of pristine conditions, and would help to quantify downward C fluxes and environmental changes related to this CO2 abstraction process. (author)

  6. Vpliv CO 2 na izkoristke sinteze metanola

    OpenAIRE

    Štumpf, Aleš

    2011-01-01

    V diplomski nalogi smo naredili raziskavo procesa proizvodnje metanola z uvajanjem CO2 v proces. Raziskava je bila narejena za družbo Nafta Petrochem d. o. o. Proces proizvodnje smo simulirali s procesnim simulatorjem ASPEN PLUS. Na proizvodnjo metanola smo vplivali z zmanjševanjem vtoka zemeljskega plina ter z dodajanjem CO2 v proces. Določili smo tudi matematični model z linearno regresijo, vpliv zemeljskega plina na proizvodnjo metanola in vpliv dodatnega vtoka CO2 na dodatno proizvodnjo m...

  7. Structurally simple complexes of CO2

    OpenAIRE

    Murphy, Luke J.; Katherine N. Robertson; Kemp, Richard A.; Tuononen, Heikki; Clyburne, Jason A. C.

    2015-01-01

    The ability to bind CO2 through the formation of low-energy, easily-broken, bonds could prove invaluable in a variety of chemical contexts. For example, weak bonds to CO2 would greatly decrease the cost of the energy-intensive sorbent-regeneration step common to most carbon capture technologies. Furthermore, exploration of this field could lead to the discovery of novel CO2 chemistry. Reduction of complexed carbon dioxide might generate chemical feedstocks for the preparation of value-added p...

  8. The Oceanic Sink for Anthropogenic CO2

    Energy Technology Data Exchange (ETDEWEB)

    Sabine, Chris [NOAA, Seattle, WA; Feely, R. A. [NOAA Pacific Marine Environmental Laboratory; Gruber, N. [ETH Zurich, Switzerland; Key, Robert [Princeton University; Lee, K. [Pohang University of Science and Technology (POSTECH), Pohang, Republic of Korea; Bullister, J.L. [NOAA Pacific Marine Environmental Laboratory; Wanninkhof, R. [Atlantic Oceanographic & Meteorological Laboratory, NOAA; Wong, C. S. [Institute of Ocean Sciences, Climate Chemistry Laboratory, Sidney, BC Canada; Wallace, D.W.R. [IFM-GEOMAR, Leibniz Institute for Marine Sciences, Chemical Oceanography, Kiel, Germany; Tilbrook, B. [CSIRO Marine and Atmospheric Research; Millero, F. J. [University of Miami; Peng, T.-H. [Atlantic Oceanographic & Meteorological Laboratory, NOAA; Kozyr, Alexander [ORNL; Ono, Tsueno [Frontier Research System for Global Change/Institute for Global Change Research, Japan; Rios, Aida F. [Instituto de Investigaciones Marinas, Consejo Superior de Investigationes Cientificas, Spain

    2004-01-01

    Using inorganic carbon measurements from an international survey effort in the 1990s and a tracer-based separation technique, we estimate a global oceanic anthropogenic carbon dioxide (CO2) sink for the period from 1800 to 1994 of 118 19 petagrams of carbon. The oceanic sink accounts for ~48% of the total fossil-fuel and cement-manufacturing emissions, implying that the terrestrial biosphere was a net source of CO2 to the atmosphere of about 39 28 petagrams of carbon for this period. The current fraction of total anthropogenic CO2 emissions stored in the ocean appears to be about one-third of the long-term potential.

  9. CO2 sequestration and climatic change

    International Nuclear Information System (INIS)

    Since about 10 years, the underground sequestration of CO2 has been the object of intensive researches among the scientists working on climatic change. Such a process would open a new way of massive abatement of CO2 emissions. This article presents the different types of disposal sites (saline aquifers, depleted oil and gas fields, deep coal seams), the disposal duration and its stakes, the other processes under study (bio-fixation, carbonation), the risks and safety aspects of CO2 sequestration, the different projects in progress and the economic aspects of this technique. (J.S.)

  10. CO2, the promises of geological sequestration

    International Nuclear Information System (INIS)

    Trapping part of the world CO2 effluents in the deep underground is a profitable and ecological way to limit the global warming. This digest paper presents the different ways of CO2 sequestration (depleted oil and gas fields, unexploited coal seams, saline aquifers), the other possible solutions for CO2 abatement (injection in the bottom of the ocean, conversion into carbonates by injection into basic rocks, fixation by photosynthesis thanks to micro-algae cultivation), and takes stock of the experiments in progress (Snoehvit field in Norway, European project Castor). (J.S.)

  11. Economic aspects of the CO2 problem

    International Nuclear Information System (INIS)

    After a more global look at the CO2 problem, the situation in Germany and Great Britain is compared. The different trends in CO2 emission in industrialized and developing countries are explained and analyzed. Future trends are indicated, and long-term strategies are developed. A reduction of CO2 emissions is considered to be feasible only by methods based on the free market economy, not by applying the principles of order policy. Finally, the author raises the question of how the ''Toronto goal'' can be achieved. (UA)

  12. The Idea of Global CO2 Trade

    DEFF Research Database (Denmark)

    Svendsen, Gert Tinggaard

    1998-01-01

    The US has been criticized for wanting to earn a fortune on a global CO2 market. However, compared to the situation without trade and provided that such a market is designed so that it does not pay to cheat, a global CO2 market may provide the world with an epoch-making means of cost......-effective control which can solve future global environmental problems. The gains from CO2 trade may give vital financial subsidies from the EU to Eastern Europe, for example, and it will probably not pay to cheat if quotas are renewed periodically by the UN. Cheating countries are then to be excluded from further...

  13. CO2-Leaking Well - Analytical Modeling

    Science.gov (United States)

    Wertz, F.; Audigane, P.; Bouc, O.

    2009-04-01

    The long-term integrity of CO2 storage in geological system relies highly on local trapping mechanisms but also on the absence/control of any kind of outlets. Indeed numerous pathways (faults, wells, rock heterogeneities…) exist that can lead stored gas back to the surface. Thus, such leakage risks must be assessed and quantified if possible. In France, BRGM is inquired for evaluating safety criteria and developing a methodology for qualifying potential geological storage sites. This implies in particular to study the leakage scenario, here through a water-filled well as a worth scenario case. In order to determine the kinds of impacts leaking CO2 can have; knowing the velocity and flow rate of uprising CO2 is a necessity. That is why a better knowledge of CO2 in storage conditions and its behaviour with the environment is required. The following study aims at characterising the CO2 flowing into the well and then rising up in a water column over the vertical dimension. An analytical model was built that describes: - In a first step, the CO2 flow between the reservoir and the inside of the well, depending on quality and thickness of different seals, which determines the flow rate through the well. - In a second step, the CO2 uprising through an open and water filled well, however in steady state, which excludes a priori the characterisation of periodic or chaotic behaviours such as geyser formation. The objective is to give numerous orders of magnitude concerning CO2 thermodynamic properties while rising up: specific enthalpy, density, viscosity, velocity, flow, gas volume fraction and expansion, pressure and temperature gradient. Dissolution is partially taken into account, however without kinetic. The strength of this model is to compute analytically - easily and instantaneously - the 1-dimensional rising velocity of CO2 in a water column as a function of the CO2 density, interfacial tension and initial volume fraction. Characteristic speeds - the ones given by

  14. Energy Balance of Global CO_2 Recycling and Amounts of Reduction of CO_2 Emission

    OpenAIRE

    Hashimoto, K; Akiyama, E.; Habazaki, H.; Kawashima, A.; Komori, M.; Shimamura, K.; Kumagai, N.

    1997-01-01

    On the basis of tailoring of amorphous alloy electrodes for seawater electrolysis to form H_2 and amorphous alloy catalysts for conversion of CO_2 to CH_4, we are proposing global CO_2 recycling : At deserts; power generation by solar energy, at coasts close to the deserts; production of H_2 by electrolysis of seawater, production of CH_4 by the reaction of H_2 and CO_2 transported, and at energy consuming districts; combustion of CH_4, recovery of CO_2 and transportation of liquefied CO_2 to...

  15. Crystallization of CO2 ice and the absence of amorphous CO2 ice in space

    OpenAIRE

    Escribano, Rafael M.; Muñoz Caro, Guillermo M.; Cruz-Diaz, Gustavo A.; Rodríguez-Lazcano, Yamilet; Maté, Belén

    2013-01-01

    Carbon dioxide (CO2) is one of the most relevant and abundant species in astrophysical and atmospheric media. In particular, CO2 ice is present in several solar system bodies, as well as in interstellar and circumstellar ice mantles. The amount of CO2 in ice mantles and the presence of pure CO2 ice are significant indicators of the temperature history of dust in protostars. It is therefore important to know if CO2 is mixed with other molecules in the ice matrix or segregated and whether it is...

  16. CO2 binding in the (quinoline-CO2)− anionic complex

    International Nuclear Information System (INIS)

    We have studied the (quinoline-CO2)− anionic complex by a combination of mass spectrometry, anion photoelectron spectroscopy, and density functional theory calculations. The (quinoline-CO2)− anionic complex has much in common with previously studied (N-heterocycle-CO2)− anionic complexes both in terms of geometric structure and covalent bonding character. Unlike the previously studied N-heterocycles, however, quinoline has a positive electron affinity, and this provided a pathway for determining the binding energy of CO2 in the (quinoline-CO2)− anionic complex. From the theoretical calculations, we found CO2 to be bound within the (quinoline-CO2)− anionic complex by 0.6 eV. We also showed that the excess electron is delocalized over the entire molecular framework. It is likely that the CO2 binding energies and excess electron delocalization profiles of the previously studied (N-heterocycle-CO2)− anionic complexes are quite similar to that of the (quinoline-CO2)− anionic complex. This class of complexes may have a role to play in CO2 activation and/or sequestration

  17. CO2 Sensing and CO2 Regulation of Stomatal Conductance: Advances and Open Questions.

    Science.gov (United States)

    Engineer, Cawas B; Hashimoto-Sugimoto, Mimi; Negi, Juntaro; Israelsson-Nordström, Maria; Azoulay-Shemer, Tamar; Rappel, Wouter-Jan; Iba, Koh; Schroeder, Julian I

    2016-01-01

    Guard cells form epidermal stomatal gas-exchange valves in plants and regulate the aperture of stomatal pores in response to changes in the carbon dioxide (CO2) concentration ([CO2]) in leaves. Moreover, the development of stomata is repressed by elevated CO2 in diverse plant species. Evidence suggests that plants can sense [CO2] changes via guard cells and via mesophyll tissues in mediating stomatal movements. We review new discoveries and open questions on mechanisms mediating CO2-regulated stomatal movements and CO2 modulation of stomatal development, which together function in the CO2 regulation of stomatal conductance and gas exchange in plants. Research in this area is timely in light of the necessity of selecting and developing crop cultivars that perform better in a shifting climate. PMID:26482956

  18. UTJECAJ CO2 NA CEMENTNI KAMEN

    OpenAIRE

    Gaurina-Međimurec, Nediljka

    2010-01-01

    Hvatanje (kaptiranje) i geološko skladištenje CO2 predstavlja jedan od načina smanjenja ispuštanja stakleničkih plinova u atmosferu. Kritični uvjeti za sigurno skladištenje CO2 u duboko zaliježuće propusne stijene su: odgovarajuća konstrukcija bušotine i postojanje nepropusnih pokrovnih stijena. Za utiskivanje CO2 mogu se koristiti nove ili već postojeće bušotine. U oba slučaja, dugotrajni integritet utisnih bušotina (do 1 000 godina) je ključni paramertar za geološko skladištenje CO2. Utisnu...

  19. Compact, High Accuracy CO2 Monitor Project

    Data.gov (United States)

    National Aeronautics and Space Administration — This Small Business Innovative Research Phase II proposal seeks to develop a low cost, robust, highly precise and accurate CO2 monitoring system. This system will...

  20. Emerging terawatt picosecond CO2 laser technology

    International Nuclear Information System (INIS)

    The first terawatt picosecond (TWps) CO2 laser is under construction at the BNL Accelerator Test Facility (ATF). TWps-CO2 lasers, having an order of magnitude longer wavelength than the well-known table-top terawatt solid state lasers, offer new opportunities for strong-field physics research. For laser wakefield accelerators (LWFA) the advantage of the new class of lasers is due to a gain of two orders of magnitude in the ponderomotive potential. The large average power of CO2 lasers is important for the generation of hard radiation through Compton back-scattering of the laser off energetic electron beams. The authors discuss applications of TWps-CO2 lasers for LWFA modules of a tentative electron-positron collider, for γ-γ (or γ-lepton) colliders, for a possible table-top source of high-intensity x-rays and gamma rays, and the generation of polarized positron beams

  1. CO2 Capture by Cement Raw Meal

    DEFF Research Database (Denmark)

    Pathi, Sharat Kumar; Lin, Weigang; Illerup, Jytte Boll; Dam-Johansen, Kim; Hjuler, Klaus

    2013-01-01

    The cement industry is one of the major sources of CO2 emissions and is likely to contribute to further increases in the near future. The carbonate looping process has the potential to capture CO2 emissions from the cement industry, in which raw meal for cement production could be used as the...... sorbent. Cyclic experiments were carried out in a TGA apparatus using industrial cement raw meal and synthetic raw meal as sorbents, with limestone as the reference. The results show that the CO2 capture capacities of the cement raw meal and the synthetic raw meal are comparable to those of pure limestone...... capacity (Xr). This shows that raw meal could be used as a sorbent for the easy integration of the carbonate looping process into the cement pyro process for reducing CO2 emissions from the cement production process....

  2. CO2 reduction in power generation

    International Nuclear Information System (INIS)

    At the UN Climate Conferenc held in Berlin in April 1995, the German Federal Government once more confirmed its program of CO2 minimization, reinforcing its goal to curb CO2 emissions due to power generation by 25% or 30% by the year 2005. This is based on conditions in 1987, when CO2 emissions in the old German federal states amounted to 715 million tons and, in the new federal states, to 345 million tons, i.e a total of 1060 million tons of CO2. The national program is part of the strategy of climate protection pursued by the European Union, and also of the basic international convention on protection of the global climate. That strategy is to limit to a tolerable level all manmade changes in climate. The greenhouse effect plays an improtant role in this respect. (orig.)

  3. CO2 Removal from Mars EMU Project

    Data.gov (United States)

    National Aeronautics and Space Administration — A practical CO2 control system for ExtraVehicular Activity (EVA) on Mars have not yet been developed. TDA Research, Inc. proposes to develop a durable,...

  4. Compact, High Accuracy CO2 Monitor Project

    Data.gov (United States)

    National Aeronautics and Space Administration — This Small Business Innovative Research Phase I proposal seeks to develop a low cost, robust, highly precise and accurate CO2 monitoring system. This system will...

  5. CO2 Removal from Mars EMU Project

    Data.gov (United States)

    National Aeronautics and Space Administration — CO2 control for during ExtraVehicular Activity (EVA) on mars is challenging. Lithium hydroxide (LiOH) canisters have impractical logistics penalties, and...

  6. The ATLAS IBL CO2 Cooling System

    CERN Document Server

    Verlaat, Bartholomeus; The ATLAS collaboration

    2016-01-01

    The Atlas Pixel detector has been equipped with an extra B-layer in the space obtained by a reduced beam pipe. This new pixel detector called the ATLAS Insertable B-Layer (IBL) is installed in 2014 and is operational in the current ATLAS data taking. The IBL detector is cooled with evaporative CO2 and is the first of its kind in ATLAS. The ATLAS IBL CO2 cooling system is designed for lower temperature operation (<-35⁰C) than the previous developed CO2 cooling systems in High Energy Physics experiments. The cold temperatures are required to protect the pixel sensors for the high expected radiation dose up to 550 fb^-1 integrated luminosity. This paper describes the design, development, construction and commissioning of the IBL CO2 cooling system. It describes the challenges overcome and the important lessons learned for the development of future systems which are now under design for the Phase-II upgrade detectors.

  7. Partitioning of the Leaf CO2 Exchange into Components Using CO2 Exchange and Fluorescence Measurements.

    Science.gov (United States)

    Laisk, A.; Sumberg, A.

    1994-10-01

    Photorespiration was calculated from chlorophyll fluorescence and ribulose-1,5-bisphosphate carboxylase/oxygenase (Rubisco) kinetics and compared with CO2 evolution rate in the light, measured by three gas-exchange methods in mature sunflower (Helianthus annuus L.) leaves. The gas-exchange methods were (a) postillumination CO2 burst at unchanged CO2 concentration, (b) postillumination CO2 burst with simultaneous transfer into CO2-free air, and (c) extrapolation of the CO2 uptake to zero CO2 concentration at Rubisco active sites. The steady-state CO2 compensation point was proportional to O2 concentration, revealing the Rubisco specificity coefficient (Ksp) of 86. Electron transport rate (ETR) was calculated from fluorescence, and photorespiration rate was calculated from ETR using CO2 and O2 concentrations, Ksp, and diffusion resistances. The values of the best-fit mesophyll diffusion resistance for CO2 ranged between 0.3 and 0.8 s cm-1. Comparison of the gas-exchange and fluorescence data showed that only ribulose-1,5-bisphosphate (RuBP) carboxylation and photorespiratory CO2 evolution were present at limiting CO2 concentrations. Carboxylation of a substrate other than RuBP, in addition to RuBP carboxylation, was detected at high CO2 concentrations. A simultaneous decarboxylation process not related to RuBP oxygenation was also detected at high CO2 concentrations in the light. We propose that these processes reflect carboxylation of phosphoenolpyruvate, formed from phosphoglyceric acid and the subsequent decarboxylation of malate. PMID:12232361

  8. Natural Analogues of CO2 Geological Storage

    International Nuclear Information System (INIS)

    Geological storage of carbon dioxide is nowadays, internationally considered as the most effective method for greenhouse gas emission mitigation, in order to minimize the global climate change universally accepted. Nevertheless, the possible risks derived of this long-term storage have a direct influence on its public acceptance. Among the favourable geological formations to store CO2, depleted oil and gas fields, deep saline reservoirs, and unamiable coal seams are highlighted. One of the most important objectives of the R and D projects related to the CO2 geological storage is the evaluation of the CO2 leakage rate through the above mentioned geological formations. Therefore, it is absolutely necessary to increase our knowledge on the interaction among CO2, storage and sealing formations, as well as on the flow paths and the physical resistance of the sealing formation. The quantification of the CO2 leakage rate is essential to evaluate the effects on the human and animal health, as well as for the ecosystem and water quality. To achieve these objectives, the study of the natural analogues is very useful in order to know the natural leakage rate to the atmosphere, its flow paths, the physical, chemical and mineralogical modifications due to the long term interaction processes among the CO2 and the storage and sealing formations, as well as the effects on the groundwaters and ecosystems. In this report, we have tried to summarise the main characteristics of the natural reservoirs and surficial sources of CO2, which are both natural analogues of the geological storage and CO2 leakage, studied in EEUU, Europe and Australia. The main objective of this summary is to find the possible applications for long-term risk prediction and for the performance assessment by means of conceptual and numerical modelling, which will allow to validate the predictive models of the CO2 storage behaviour, to design and develop suitable monitoring techniques to control the CO2 behaviour

  9. The twelve principles of CO2 Chemistry

    OpenAIRE

    Poliakoff, Martyn; Leitner, Walter; Streng, Emelia S.

    2015-01-01

    This paper introduces a set of 12 Principles, based on the acronym CO2 CHEMISTRY, which are intended to form a set of criteria for assessing the viability of different processes or reactions for using CO2 as a feedstock for making organic chemicals. The principles aim to highlight the synergy of Carbon Dioxide Utilisation (CDU) with the components of green and sustainable chemistry as well as briefly pointing out the connection to the energy sector.

  10. CO2 pipelines material and safety considerations

    OpenAIRE

    Bilio, M.; S. Brown; Fairweather, M.; Mahgerefteh, H.; IChemE

    2009-01-01

    This paper presents an overview of some of the most important factors and areas of uncertainty affecting integrity and accurate hazard assessment of CO2 pipelines employed as part of the Carbon Capture and Sequestration (CCS) chain. These include corrosion, hydrate formation, hydrogen embrittlement and propensity to fast running ductile and brittle factures. Special consideration is given to the impact of impurities within the CO2 feed from the various capture technologies on t...

  11. Can increasing CO2 cool Antarctica?

    OpenAIRE

    Schmithüsen, Holger; Notholt, Justus; König-Langlo, Gert; Lemke, Peter

    2014-01-01

    CO2 is the strongest anthropogenic forcing agent for climate change since pre-industrial times. Like other greenhouse gases, CO2 absorbs terrestrial surface radiation and causes emission from the atmosphere to space. As the surface is generally warmer than the atmosphere, the total long-wave emission to space is commonly less than the surface emission. However, this does not hold true for the high elevated areas of central Antarctica. Our investigations show, that for the high elevated ar...

  12. Efficient pulsed CO2 laser calculations

    Science.gov (United States)

    Stone, David H.; Honey, David A.

    1991-02-01

    A computationally efficient scheme for generating pumping rates was developed for use with a pulsed CO2 laser model. A steady-state solution of the Boltzmann electron transport equation generates the rates. Vibrational temperatures for the CO2 and N2 populations are determined by iterating the Boltzmann solver with the rate equation model. Rapid convergence and coarse grids allow quick calculations of pulse shape, peak power, and total energy. Results compare well with a fully time-dependent Boltzmann solver.

  13. Carbonated concrete blocks for CO2 captation

    OpenAIRE

    Courard, Luc; Parmentier, Véronique; Michel, Frédéric

    2015-01-01

    The CO2 captation process called carbonation, improves specific properties of the concrete during the conversion of carbon dioxide CO2 into calcium carbonate CaCO3. Current environmental concerns motivate the study of carbonation in order to maximize the absorption of carbon dioxide. Moreover, lightweight concrete with bio-based products knows an interesting development in the construction field, especially as thermal insulation panels for walls in buildings. Concrete blocks produced with mis...

  14. Supercritical CO2 Extraction of Ethanol

    OpenAIRE

    GÜVENÇ, A.; MEHMETOĞLU, Ü.; ÇALIMLI, A.

    1999-01-01

    Extraction of ethanol was studied from both synthetic ethanol solution and fermentation broth using supercritical CO2 in an extraction apparatus in ranges of 313 to 333 K and 80 to 160 atmospheres, for varying extraction times. The experimental system consists mainly of four parts: a CO2 storage system, a high-pressure liquid pump, an extractor and a product collection unit. Samples were analyzed by gas chromatography. Effects of temperature, pressure, extraction time, initial ethan...

  15. Harvesting Energy from CO2 Emissions

    OpenAIRE

    Hamelers, H.V.M.; Schaetzle, O; Paz-García, J. M.; Biesheuvel, P. M.; Buisman, C.J.N.

    2013-01-01

    When two fluids with different compositions are mixed, mixing energy is released. This holds true for both liquids and gases, though in the case of gases, no technology is yet available to harvest this energy source. Mixing the CO2 in combustion gases with air represents a source of energy with a total annual worldwide capacity of 1570 TWh. To harvest the mixing energy from CO2-containing gas emissions, we use pairs of porous electrodes, one selective for anions and the o...

  16. Blowdown Simulation of CO2 Pipelines

    OpenAIRE

    Collard, A

    2015-01-01

    Pipelines are the most practical option for transporting large volumes of captured CO2 to appropriate storage sites as part of the Carbon Capture and Storage (CCS) process. Proper maintenance, including periodic blowdown of pipelines or pipeline sections, is necessary for their safe operation, a pre-requisite for the public acceptance of CCS. Given the relatively high Joule-Thomson coefficient of CO2, blowdown can present significant risks to pipeline infrastructure. Depressurisation will res...

  17. Flow assurance studies for CO2 transport

    OpenAIRE

    Veltin, J.; Belfroid, S.P.C.

    2013-01-01

    In order to compensate for the relative lack of experience of the CCTS community, Flow Assurance studies of new CO2 pipelines and networks are a very important step toward reliable operation. This report details a typical approach for Flow Assurance study of CO2 transport pipeline. Considerations to take during the design of a pipeline are highlighted, with an emphasis on operability of the system. The steady state aspects of a pipeline operation are first addressed, putting some highlight in...

  18. Combustion of hythane diluted with CO2

    Directory of Open Access Journals (Sweden)

    Hraiech Ibtissem

    2015-01-01

    Full Text Available With increasing concern about energy shortage and environmental protection, improving engine fuel economy and reducing exhaust emissions have become major research topics in combustion and engine development. Hythane (a blend of hydrogen H2 and natural gas NG has generated a significant interest as an alternative fuel for the future. This paper describes an experimental study of the effects of CO2 addition on the stability of a turbulent jet diffusion NG-H2 flame. The mole fraction of hydrogen (% H2 in NG-H2 mixture was varied from 0% to 50%. The equivalence ratio of the hythane/CO2/air mixture was kept at stoichiometry. The results show that the lift-off height increases with the addition of CO2 at various % H2 content in hythane. However, we observe that with 20% H2, we can obtain a stable flame diluted with 40% CO2, while for 0% H2, the flame is blown out above 20% CO2. This means that the limits of flame blowing out are pushed with the additions of H2. Moreover, the results show that for %H2 content in NG-H2 fuel up to 10%, the addition of CO2 could produce lifted flame if the % CO2 is low. At higher % CO2 dilution, flame would remain attached until blow-out. This is mainly due to the fact that the dilution leads to ejection velocities very high but reactivity of the mixture does not change so the flame tends to stretch.

  19. CO2 emission from nuclear electricity

    International Nuclear Information System (INIS)

    A lot of controversy can be found in open literature on the carbon balance attributed to the electricity generated by nuclear power plants. Extremely scattered values are spread about varying over more than two orders of magnitude from one study to another. In this paper, we work out a realistic estimation of the CO2 emission that ought to be allocated to nuclear energy, based on a technical analysis of the life cycle of the uranium fuel. It includes going all the way from the front-end (mining, purification, enrichment and fuel fabrication) up to the back-end (including recycling and waste conditioning) through the production part inside the reactor. In the analysis, the CO2 emitted during both the plant construction phase and the deconstruction and dismantling phases has been evaluated and added to the amount of greenhouse gas released during operation. It is shown that the final carbon footprint of nuclear electricity is highly dependent on the country considered and its electricity generation mix. A special focus is given on France's case, whose CO2 balance is closely linked to the nuclear share. In France, thanks to an electric power mainly generated by nuclear and hydroelectricity, the actual carbon footprint of nuclear electricity has been estimated to be as low as 1.56 g CO2/kWh in which the different contributions are: mining: 0.77 g CO2/kWh, front-end: 0.12 g CO2/kWh, production: 0.41 g CO2/kWh and back-end: 0.26 g CO2/kWh. In France the carbon footprint of nuclear energy is 250 times lower than gas-fired power plants and 600 times lower than coal plants

  20. Study on CO2 global recycling system

    International Nuclear Information System (INIS)

    In order to assist in finding ways to mitigate CO2 emission and to slow the depletion of fossil fuels we have established and evaluated a representative system, which consists of three technologies developed in our laboratory. These technologies were in CO2 recovery, hydrogen production and methanol synthesis and in addition we established the necessary supporting systems. Analysis of outline designs of the large scale renewable energy power generation system and this system and energy input for building plant, energy input for running plant has been conducted based on a case using this system for a 1000-MW coal fired power plant, followed by an evaluation of the material balance and energy balance. The results are as follows. Energy efficiency is 34%, the CO2 reduction rate is 41%, the balance ratio of the energy and CO2 of the system is 2.2 and 1.8, respectively, on the assumption that the primary renewable energy is solar thermal power generation, the stationary CO2 emission source is a coal-fired power plant and the generation efficiency of the methanol power plant is 60%. By adopting the system, 3.7 million tons of CO2 can be recovered, approximately 2.7 million tons of methanol can be produced, and 15.4 billion kWh of electricity can be generated per year. Compared to generating all electrical power using only coal, approximately 2.6 million tons of coal per year can be saved and approximately 2.15 million tons of CO2 emission can be reduced. Therefore, it is clearly revealed that this system would be effective to reduce CO2 emissions and to utilize renewable energy

  1. Udvikling af CO2 neutralt byrumsarmatur

    DEFF Research Database (Denmark)

    Poulsen, Peter Behrensdorff; Dam-Hansen, Carsten; Corell, Dennis Dan;

    Denne rapport indeholder en beskrivelse af arbejdet udført i og resultaterne af forsknings- og udviklingsprojektet ” Udvikling af CO2 neutralt byrumsarmatur” og udgør slutrapportering for dette projekt.......Denne rapport indeholder en beskrivelse af arbejdet udført i og resultaterne af forsknings- og udviklingsprojektet ” Udvikling af CO2 neutralt byrumsarmatur” og udgør slutrapportering for dette projekt....

  2. World premiere of CO2 capture

    International Nuclear Information System (INIS)

    On March 15, 2006, the very first industrial pilot facility of CO2 capture was inaugurated in Denmark in the framework of the Castor project. This facility allows to capture about 90% of the CO2 from the smokes of a coal-fired power plant thanks to a solvent extraction process. During the process, the solvent is regenerated and reinjected in the absorber. Short paper. (J.S.)

  3. Toxic emissions and devalued CO2-neutrality

    DEFF Research Database (Denmark)

    Czeskleba-Dupont, Rolf

    friendly effects of substituting wood burning for fossil fuels. With reference to Bent Sørensen's classical work on 'Renewable Energy' the assumption of CO2-neutrality regarding incineration is problematised when applied to plants with long rotation periods as trees. Registered CO2-emissions from wood...... burning are characterised together with particle and PAH emissions. The positive treatment of wood stove-technology in the Danish strategy for sustainable development (draft 2007) is critically evaluated and approaches to better regulation are identified....

  4. Density of aqueous solutions of CO2

    Energy Technology Data Exchange (ETDEWEB)

    Garcia, Julio E.

    2001-10-10

    In this report, we present a numerical representation for the partial molar volume of CO2 in water and the calculation of the corresponding aqueous solution density. The motivation behind this work is related to the importance of having accurate representations for aqueous phase properties in the numerical simulation of carbon dioxide disposal into aquifers as well as in geothermal applications. According to reported experimental data the density of aqueous solutions of CO2 can be as much as 2-3% higher than pure water density. This density variation might produce an influence on the groundwater flow regime. For instance, in geologic sequestration of CO2, convective transport mixing might occur when, several years after injection of carbon dioxide has stopped, the CO2-rich gas phase is concentrated at the top of the formation, just below an overlaying caprock. In this particular case the heavier CO2 saturated water will flow downward and will be replaced by water with a lesser CO2 content.

  5. Optimal reductions in CO2 emissions

    International Nuclear Information System (INIS)

    Current optimizing climate-economy models use CO2 uptake functions that greatly underestimates both peak atmospheric CO2 concentrations and the time horizon of elevated CO2. As a result these models underestimate potential global warming damages. Here, a more realistic, but practical, carbon cycle parameterization is developed that can be incorporated within an optimizing climate-economy model framework. This method is utilized in conjunction with DICE model (Nordhaus, 1994) to estimate optimal reductions in CO2 emissions. The results are shown to be extremely sensitive to the pure rate of time preference, ρ. For ρ=3% (Norhaus' preferred value), our model predicts an optimal CO2 emission reduction of 13% by the year 2045, as compared to 11% in the original DICE model. But, for ρ=0% the optimal emissions reduction rises to 79% in the year 2045 and to 97% by the year 2200. We argue that energy policy should be guided by the ρ=0% results for both economic and ethical reasons. A steady-state analysis performed using DICE model supports the argument that large fractional reductions in CO2 emissions should be undertaken. (author)

  6. CO2 efflux from cleared mangrove peat.

    Directory of Open Access Journals (Sweden)

    Catherine E Lovelock

    Full Text Available BACKGROUND: CO(2 emissions from cleared mangrove areas may be substantial, increasing the costs of continued losses of these ecosystems, particularly in mangroves that have highly organic soils. METHODOLOGY/PRINCIPAL FINDINGS: We measured CO(2 efflux from mangrove soils that had been cleared for up to 20 years on the islands of Twin Cays, Belize. We also disturbed these cleared peat soils to assess what disturbance of soils after clearing may have on CO(2 efflux. CO(2 efflux from soils declines from time of clearing from ∼10,600 tonnes km(-2 year(-1 in the first year to 3000 tonnes km(2 year(-1 after 20 years since clearing. Disturbing peat leads to short term increases in CO(2 efflux (27 umol m(-2 s(-1, but this had returned to baseline levels within 2 days. CONCLUSIONS/SIGNIFICANCE: Deforesting mangroves that grow on peat soils results in CO(2 emissions that are comparable to rates estimated for peat collapse in other tropical ecosystems. Preventing deforestation presents an opportunity for countries to benefit from carbon payments for preservation of threatened carbon stocks.

  7. Shapley Ranking of Wines

    OpenAIRE

    Ginsburgh, Victor; Zang, ISRAEL

    2012-01-01

    We suggest a new game-theory-based ranking method for wines, in which the Shapley Value of each wine is computed, and wines are ranked according to their Shapley Values. Judges should find it simpler to use, since they are not required to rank order or grade all the wines, but merely to choose the group of those that they find meritorious. Our ranking method is based on the set of reasonable axioms that determine the Shapley Value as the unique solution of an underlying cooperative game. Unli...

  8. Application of CO2 in BOF%转炉应用CO2技术

    Institute of Scientific and Technical Information of China (English)

    万雪峰; 曹东; 刘祥; 朱晓雷; 廖相巍

    2015-01-01

    By the thermodynamic analysis of top blowing CO2 in the converter,combined with laboratory simulation re-sult of top blowing O2+CO2 mixture gas in converter,some key parameters of CO2 used in converter were established. It is concluded that although pure CO2 injected in the converter could achieve decarburize,the drop of temperature was rath-er large. When the CO2 supplying intensity was 3.0 m3/(t·min),the reduction of temperature was 15.1℃/min;By blow-ing O2+CO2 mixture gas,temperature balance could be realized,but the largest theoretical proportion of CO2 in mixture gas was 79.1%;with the increase of CO2 proportion,the carbon and oxygen product of molten steel at the blowing end was reduced,under the condition of φ(CO2)∶φ(O2)=1∶1,the carbon and oxygen product could be controlled in the range of (25~32)×10-8.%通过对转炉顶吹CO2的热力学分析,结合实验室模拟转炉顶吹O2+CO2混合气体试验结果,确立了CO2在转炉中应用的关键参数。得出在转炉中顶吹纯CO2虽可脱碳,但温降较大,顶吹CO2供气强度为3.0 m3/(t·min)时,钢液温降速率为15.1℃/min;通过喷吹O2+CO2混合气体可实现温度平衡,但CO2配比的最大理论比例为79.1%;随着混合气体中CO2比例增大,吹炼终点钢液碳氧积降低,当φ(CO2)∶φ(O2)=1∶1时可控碳氧积为(25~32)×10-8。

  9. Global CO2 simulation using GOSAT-based surface CO2 flux estimates

    Science.gov (United States)

    Takagi, H.; Oda, T.; Saito, M.; Valsala, V.; Belikov, D.; Saeki, T.; Saito, R.; Morino, I.; Uchino, O.; Yoshida, Y.; Yokota, Y.; Bril, A.; Oshchepkov, S.; Andres, R. J.; Maksyutov, S.

    2012-04-01

    Investigating the distribution and temporal variability of surface CO2 fluxes is an active research topic in the field of contemporary carbon cycle dynamics. The technique central to this effort is atmospheric inverse modeling with which surface CO2 fluxes are estimated by making corrections to a priori flux estimates such that mismatches between model-predicted and observed CO2 concentrations are minimized. Past investigations were carried out by utilizing CO2 measurements collected in global networks of surface-based monitoring sites. Now, datasets of column-averaged CO2 dry air mole fraction (XCO2) retrieved from spectral soundings collected by GOSAT are available for complementing the surface-based CO2 observations. These space-based XCO2 data are expected to enhance the spatiotemporal coverage of the existing surface observation network and thus reduce uncertainty associated with the surface flux estimates. We estimated monthly CO2 fluxes in 64 sub-continental regions from a subset of the surface-based GLOBALVIEW CO2 data and the GOSAT FTS SWIR Level 2 XCO2 retrievals. We further simulated CO2 concentrations in 3-D model space using the surface flux estimates obtained. In this presentation, we report the result of a comparison between the simulated CO2 concentrations and independent surface observations. As part of an effort in inter-comparing GOSAT-based surface CO2 flux estimates, we also look at results yielded with XCO2 data retrieved with the PPDF-DOAS algorithm and those made available by the NASA Atmospheric CO2 Observations from Space team. For this study, we used version 08.1 of the National Institute for Environmental Studies atmospheric transport model, which was driven by the Japan Meteorological Agency's JCDAS wind analysis data. The CO2 forward simulations were performed on 2.5° × 2.5° horizontal grids at 32 vertical levels between the surface and the top of the atmosphere. The a priori flux dataset used was comprised of the sum of four

  10. Oxifuel combustión for CO2 capture. Application of computacional fluid dynamics techniques

    OpenAIRE

    L. Álvarez

    2013-01-01

    The overall combustion behaviour for coals of different rank was experimentally and numerically studied in air and oxy-fuel conditions in an entrained flow reactor. High CO2 concentrations seemed to affect volatile yield and nitrogen distribution, and also the subsequent char reactivity. To obtain similar or better ignition and combustion properties under oxy-firing conditions to those attained in air, the oxygen concentration in the CO2 and H2O(v) mixture must be about 30%. During oxy-fuel c...

  11. Fingerprinting captured CO2 using natural tracers: Determining CO2 fate and proving ownership

    Science.gov (United States)

    Flude, Stephanie; Gilfillan, Stuart; Johnston, Gareth; Stuart, Finlay; Haszeldine, Stuart

    2016-04-01

    In the long term, captured CO2 will most likely be stored in large saline formations and it is highly likely that CO2 from multiple operators will be injected into a single saline formation. Understanding CO2 behavior within the reservoir is vital for making operational decisions and often uses geochemical techniques. Furthermore, in the event of a CO2 leak, being able to identify the owner of the CO2 is of vital importance in terms of liability and remediation. Addition of geochemical tracers to the CO2 stream is an effective way of tagging the CO2 from different power stations, but may become prohibitively expensive at large scale storage sites. Here we present results from a project assessing whether the natural isotopic composition (C, O and noble gas isotopes) of captured CO2 is sufficient to distinguish CO2 captured using different technologies and from different fuel sources, from likely baseline conditions. Results include analytical measurements of CO2 captured from a number of different CO2 capture plants and a comprehensive literature review of the known and hypothetical isotopic compositions of captured CO2 and baseline conditions. Key findings from the literature review suggest that the carbon isotope composition will be most strongly controlled by that of the feedstock, but significant fractionation is possible during the capture process; oxygen isotopes are likely to be controlled by the isotopic composition of any water used in either the industrial process or the capture technology; and noble gases concentrations will likely be controlled by the capture technique employed. Preliminary analytical results are in agreement with these predictions. Comparison with summaries of likely storage reservoir baseline and shallow or surface leakage reservoir baseline data suggests that C-isotopes are likely to be valuable tracers of CO2 in the storage reservoir, while noble gases may be particularly valuable as tracers of potential leakage.

  12. Accelerated carbonation of steel slags using CO2 diluted sources: CO2 uptakes and energy requirements

    Directory of Open Access Journals (Sweden)

    Renato eBaciocchi

    2016-01-01

    Full Text Available This work presents the results of carbonation experiments performed on Basic Oxygen Furnace (BOF steel slag samples employing gas mixtures containing 40 and 10% CO2 vol. simulating the gaseous effluents of gasification and combustion processes respectively, as well as 100% CO2 for comparison purposes. Two routes were tested, the slurry phase (L/S=5 l/kg, T=100 °C and Ptot=10 bar and the thin film (L/S =0.3-0.4 l/kg, T=50 °C and Ptot=7-10 bar routes. For each one, the CO2 uptake achieved as a function of the reaction time was analyzed and on this basis the energy requirements associated to each carbonation route and gas mixture composition were estimated considering to store the CO2 emissions of a medium size natural gas fired power plant (20 MW. For the slurry phase route, maximum CO2 uptakes ranged from around 8% at 10% CO2, to 21.1% (BOF-a and 29.2% (BOF-b at 40% CO2 and 32.5% (BOF-a and 40.3% (BOF-b at 100% CO2. For the thin film route, maximum uptakes of 13% (BOF-c and 19.5% (BOF-d at 40% CO2, and 17.8% (BOF-c and 20.2% (BOF-d at 100% were attained. The energy requirements of the two analyzed process routes appeared to depend chiefly on the CO2 uptake of the slag. For both process route, the minimum overall energy requirements were found for the tests with 40% CO2 flows (i.e. 1400-1600 MJ/t CO2 for the slurry phase and 2220-2550 MJ/t CO2 for the thin film route.

  13. Precursory volcanic CO2 signals from space

    Science.gov (United States)

    Schwandner, Florian M.; Carn, Simon A.; Kataoka, Fumie; Kuze, Akihiko; Shiomi, Kei; Goto, Naoki

    2016-04-01

    Identification of earliest signals heralding volcanic unrest benefits from the unambiguous detection of precursors that reflect deviation of magmatic systems from metastable background activity. Ascent and emplacement of new basaltic magma at depth may precede eruptions by weeks to months. Transient localized carbon dioxide (CO2) emissions stemming from exsolution from depressurized magma are expected, and have been observed weeks to months ahead of magmatic surface activity. Detecting such CO2 precursors by continuous ground-based monitoring operations is unfortunately not a widely implemented method yet, save a handful of volcanoes. Detecting CO2 emissions from space offers obvious advantages - however it is technologically challenging, not the least due to the increasing atmospheric burden of CO2, against which a surface emission signal is hard to discern. In a multi-year project, we have investigated the feasibility of space-borne detection of pre-eruptive volcanic CO2 passive degassing signals using observations from the Greenhouse Gas Observing SATellite (GOSAT). Since 2010, we have observed over 40 active volcanoes from space using GOSAT's special target mode. Over 72% of targets experienced at least one eruption over that time period, demonstrating the potential utility of space-borne CO2 observations in non-imaging target-mode (point source monitoring mode). While many eruption precursors don't produce large enough CO2 signals to exceed space-borne detection thresholds of current satellite sensors, some of our observations have nevertheless already shown significant positive anomalies preceding eruptions at basaltic volcanoes. In 2014, NASA launched its first satellite dedicated to atmospheric CO2 observation, the Orbiting Carbon Observatory (OCO-2). Its observation strategy differs from the single-shot GOSAT instrument. At the expense of GOSAT's fast time series capability (3-day repeat cycle, vs. 16 for OCO-2), its 8-footprint continuous swath can slice

  14. How to Rank Journals.

    Science.gov (United States)

    Bradshaw, Corey J A; Brook, Barry W

    2016-01-01

    There are now many methods available to assess the relative citation performance of peer-reviewed journals. Regardless of their individual faults and advantages, citation-based metrics are used by researchers to maximize the citation potential of their articles, and by employers to rank academic track records. The absolute value of any particular index is arguably meaningless unless compared to other journals, and different metrics result in divergent rankings. To provide a simple yet more objective way to rank journals within and among disciplines, we developed a κ-resampled composite journal rank incorporating five popular citation indices: Impact Factor, Immediacy Index, Source-Normalized Impact Per Paper, SCImago Journal Rank and Google 5-year h-index; this approach provides an index of relative rank uncertainty. We applied the approach to six sample sets of scientific journals from Ecology (n = 100 journals), Medicine (n = 100), Multidisciplinary (n = 50); Ecology + Multidisciplinary (n = 25), Obstetrics & Gynaecology (n = 25) and Marine Biology & Fisheries (n = 25). We then cross-compared the κ-resampled ranking for the Ecology + Multidisciplinary journal set to the results of a survey of 188 publishing ecologists who were asked to rank the same journals, and found a 0.68-0.84 Spearman's ρ correlation between the two rankings datasets. Our composite index approach therefore approximates relative journal reputation, at least for that discipline. Agglomerative and divisive clustering and multi-dimensional scaling techniques applied to the Ecology + Multidisciplinary journal set identified specific clusters of similarly ranked journals, with only Nature & Science separating out from the others. When comparing a selection of journals within or among disciplines, we recommend collecting multiple citation-based metrics for a sample of relevant and realistic journals to calculate the composite rankings and their relative uncertainty windows. PMID:26930052

  15. How to Rank Journals.

    Directory of Open Access Journals (Sweden)

    Corey J A Bradshaw

    Full Text Available There are now many methods available to assess the relative citation performance of peer-reviewed journals. Regardless of their individual faults and advantages, citation-based metrics are used by researchers to maximize the citation potential of their articles, and by employers to rank academic track records. The absolute value of any particular index is arguably meaningless unless compared to other journals, and different metrics result in divergent rankings. To provide a simple yet more objective way to rank journals within and among disciplines, we developed a κ-resampled composite journal rank incorporating five popular citation indices: Impact Factor, Immediacy Index, Source-Normalized Impact Per Paper, SCImago Journal Rank and Google 5-year h-index; this approach provides an index of relative rank uncertainty. We applied the approach to six sample sets of scientific journals from Ecology (n = 100 journals, Medicine (n = 100, Multidisciplinary (n = 50; Ecology + Multidisciplinary (n = 25, Obstetrics & Gynaecology (n = 25 and Marine Biology & Fisheries (n = 25. We then cross-compared the κ-resampled ranking for the Ecology + Multidisciplinary journal set to the results of a survey of 188 publishing ecologists who were asked to rank the same journals, and found a 0.68-0.84 Spearman's ρ correlation between the two rankings datasets. Our composite index approach therefore approximates relative journal reputation, at least for that discipline. Agglomerative and divisive clustering and multi-dimensional scaling techniques applied to the Ecology + Multidisciplinary journal set identified specific clusters of similarly ranked journals, with only Nature & Science separating out from the others. When comparing a selection of journals within or among disciplines, we recommend collecting multiple citation-based metrics for a sample of relevant and realistic journals to calculate the composite rankings and their relative uncertainty windows.

  16. Memory Efficient Ranking.

    Science.gov (United States)

    Moffat, Alistair; And Others

    1994-01-01

    Describes an approximate document ranking process that uses a compact array of in-memory, low-precision approximations for document length. Combined with another rule for reducing the memory required by partial similarity accumulators, the approximation heuristic allows the ranking of large document collections using less than one byte of memory…

  17. Successful Combination of Sequential Gene Therapy and Rescue Allo-HSCT in Two Children with X-CGD - Importance of Timing.

    Science.gov (United States)

    Siler, Ulrich; Paruzynski, Anna; Holtgreve-Grez, Heidi; Kuzmenko, Elena; Koehl, Ulrike; Renner, Eleonore D; Alhan, Canan; de Loosdrecht, Arjan A van; Schwäble, Joachim; Pfluger, Thomas; Tchinda, Joelle; Schmugge, Markus; Jauch, Anna; Naundorf, Sonja; Kühlcke, Klaus; Notheis, Gundula; Güngor, Tayfun; Kalle, Christof V; Schmidt, Manfred; Grez, Manuel; Seger, Reinhard; Reichenbach, Janine

    2015-01-01

    We report on a series of sequential events leading to long-term survival and cure of pediatric X-linked chronic granulomatous disease (X-CGD) patients after gamma-retroviral gene therapy (GT) and rescue HSCT. Due to therapyrefractory life-threatening infections requiring hematopoietic stem cell transplantation (HSCT) but absence of HLAidentical donors, we treated 2 boys with X-CGD by GT. Following GT both children completely resolved invasive Aspergillus nidulans infections. However, one child developed dual insertional activation of ecotropic viral integration site 1 (EVI1) and signal transducer and activator of transcription 3 (STAT3) genes, leading to myelodysplastic syndrome (MDS) with monosomy 7. Despite resistance to mismatched allo-HSCT with standard myeloablative conditioning, secondary intensified rescue allo-HSCT resulted in 100 % donor chimerism and disappearance of MDS. The other child did not develop MDS despite expansion of a clone with a single insertion in the myelodysplasia syndrome 1 (MDS1) gene and was cured by early standard allo-HSCT. The slowly developing dominance of clones harboring integrations in MDS1-EVI1 may guide clinical intervention strategies, i.e. early rescue allo-HSCT, prior to malignant transformation. GT was essential for both children to survive and to clear therapy-refractory infections, and future GT with safer lentiviral self-inactivated (SIN) vectors may offer a therapeutic alternative for X-CGD patients suffering from life-threatening infections and lacking HLA-identical HSC donors. PMID:25981636

  18. Validation of Airborne CO2 Laser Measurements

    Science.gov (United States)

    Browell, E. V.; Dobler, J. T.; Kooi, S.; Fenn, M. A.; Choi, Y.; Vay, S. A.; Harrison, F. W.; Moore, B.; Zaccheo, T. S.

    2010-12-01

    This paper discusses the flight test validation of a unique, multi-frequency, intensity-modulated, single-beam laser absorption spectrometer (LAS) that operates near 1.57 μm for remote column CO2 measurements. This laser system is under development for a future space-based mission to determine the global distribution of regional-scale CO2 sources and sinks, which is the objective of the NASA Active Sensing of CO2 Emissions during Nights, Days, and Seasons (ASCENDS) mission. A prototype of this LAS system, called the Multi-frequency Fiber Laser Lidar (MFLL), was developed by ITT, and it has been flight tested in nine airborne campaigns since May 2005. This paper focuses on the most recent results obtained over the last two years of flight-testing where the MFLL remote CO2 column measurements were evaluated against airborne in situ CO2 profile measurements traceable to World Meteorological Organization standards. A comprehensive multiple-aircraft flight test program was conducted over Oklahoma and Virginia in July-August 2009. The MFLL obtained surface reflectance and average CO2 column variations along the 50-km flight legs over the Department of Energy (DOE) Atmospheric Radiation Measurement (ARM) Central Facility (CF) in Lamont, Oklahoma; over rural Virginia and North Carolina; and over the Chesapeake Bay. For a flight altitude of 4.6 km, the average signal to noise ratio (SNR) for a 1-s CO2 column measurement was found to be 760, which is the equivalent of a CO2 mixing ratio precision of 0.60 ppmv, and for a 10-s average the SNR was found to be 2002 or 0.20 ppmv. Absolute comparisons of MFLL-derived and in situ-derived CO2 column measurements were made for all daytime flights conducted over Oklahoma and Virginia with an average agreement to within 0.32 ppmv. A major ASCENDS flight test campaign was conducted using the NASA DC-8 during 6-18 July 2010. The MFLL system and associated in situ CO2 instrumentation were operated on DC-8 flights over the Central Valley

  19. Constraints on the atmospheric CO2 deglacial rise based on its δ13CO2 evolution

    OpenAIRE

    Lourantou, A.; Lavric, J. V.; Köhler, Peter; Barnola, J.-M.; Michel, E.; Paillard, D.; D. Raynaud; Chappellaz, J.

    2009-01-01

    The analysis of air bubbles trapped in polar ice permits the reconstruction of atmospheric evolution of greenhouse gases, such as carbon dioxide (CO2 ), on various timescales. Within this study, the simultaneous analysis of the CO2 mixing ratio and its stable carbon isotope composition (δ 13 CO2 ) over the last two deglaciations allows us to better constrain the global carbon cycle. Based on the different isotopic signatures of the ocean and the terrestrial biosphere (major reservoirs re...

  20. The Idea of Global CO2 Trade

    DEFF Research Database (Denmark)

    Svendsen, Gert Tinggaard

    1999-01-01

    The US has been criticized for wanting to earn a fortune on a global CO2 market. However, compared to the situation without trade and provided that such a market is designed so that it does not pay to cheat, a global CO2 market may provide the world with an epoch-making means of cost-effective co......The US has been criticized for wanting to earn a fortune on a global CO2 market. However, compared to the situation without trade and provided that such a market is designed so that it does not pay to cheat, a global CO2 market may provide the world with an epoch-making means of cost......-effective control which can solve future global environmental problems. The economic gains from 'hot air' distributions of permits and CO2 trade make the system politically attractive to potential participants. For example, vital financial subsidies from the EU to Eastern Europe are to be expected. It will probably...... not pay to cheat if quotas are renewed periodically by the UN. Cheating countries are then to be excluded from further profitable trade. Also, a periodical renewal of permits makes it possible to tighten target levels in the future....

  1. Economic efficiency of CO2 reduction programs

    International Nuclear Information System (INIS)

    A highly simplified time-dependent low-dimensional system has been designed to describe conceptually the interaction of climate and economy. Enhanced emission of carbon dioxide (CO2) is understood as the agent that not only favors instantaneous consumption but also causes unfavorable climate changes at a later time. The problem of balancing these two counterproductive effects of CO2 emissions on a finite time horizon is considered. The climate system is represented by just two parameters, namely a globally averaged near-surface air-temperature and a globally averaged troposheric CO2 concentration. The costs of abating CO2 emissions are monitored by a function which depends quadratically on the percentage reduction of emission compared to an 'uncontrolled emission' scenario. Parameters are fitted to historical climate data and to estimates from studies of CO2 abatement costs. Two optimization approaches, which differ from earlier attempts to describe the interaction of economy and climate, are discussed. In the 'cost oriented' strategy an optimal emission path is identified which balances the abatement costs and explicitly formulated damage costs. These damage costs, whose estimates are very uncertain, are hypothesized to be a linear function of the time-derivative of temperature. In the 'target oriented' strategy an emission path is chosen so that the abatement costs are minimal while certain restrictions on the terminal temperature and concentration change are met. (orig.)

  2. CO2 chemosensitivity during immersion in humans.

    Science.gov (United States)

    Chang, L P; Lundgren, C E

    1995-01-01

    Hypercapnic ventilatory response was compared in 9 seated subjects during head-out immersion in 35 degrees C (thermoneutral) water and during non-immersion in 28 degrees C (thermoneutral) room air. Using Read's CO2-rebreathing technique, minute ventilation (VE) and end-tidal (ET) PCO2 were sampled continuously for 4-5 min with a spirometer and a mass spectrometer, while the subject rebreathed a 6 L gas mixture initially containing 7% CO2 and 93% O2 in a bag-in-box system. The slope of the hypercapnic ventilatory response curve, expressed as delta VE/delta PETCO2, ranged from 0.76 to 2.49 L/min/mmHg. Immersion affected neither the slope nor the position of the hypercapnic ventilatory response curve. The rate of rise of PETCO2 during immersed CO2-rebreathing was significantly reduced (4.47 +/- 0.19 [SE] mmHg/min), as compared to the control value (5.67 +/- 0.24). It was concluded that the CO2 chemosensitivity during immersion in humans did not change and that the capacity to store CO2 in tissue might have been increased. PMID:8549236

  3. Rangeland -- plant response to elevated CO2

    International Nuclear Information System (INIS)

    Plots of a tallgrass prairie ecosystem were exposed to ambient and twice-ambient CO2 concentrations in open-top chambers and compared to unchambered ambient CO2 plots during the entire growing season from 1989 through 1992. Relative root production among treatments was estimated using root ingrowth bags which remained in place throughout the growing season. Latent heat flux was simulated with and without water stress. Botanical composition was estimated annuallyin all treatments. Open-top chambers appeared to reduce latent heat flux and increase water use efficiency similar to elevated CO2 when water stress was not severe, but under severe water stress, chamber effect on water use efficiency was limited. In natural ecosystems with periodic moisture stress, increased water use efficiency under elevated CO2 apparently would have a greater impact on productivity than photosynthetic pathway. Root ingrowth biomass was greater in 1990 and 1991 on elevated CO2 plots compared to ambient or chambered-ambient plots. In 1992, there was no difference in root ingrowth biomass among treatments

  4. Direct Copolymerization of CO2 and Diols

    Science.gov (United States)

    Tamura, Masazumi; Ito, Kazuki; Honda, Masayoshi; Nakagawa, Yoshinao; Sugimoto, Hiroshi; Tomishige, Keiichi

    2016-04-01

    Direct polymerization of CO2 and diols is promising as a simple and environmental-benign method in place of conventional processes using high-cost and/or hazardous reagents such as phosgene, carbon monoxide and epoxides, however, there are no reports on the direct method due to the inertness of CO2 and severe equilibrium limitation of the reaction. Herein, we firstly substantiate the direct copolymerization of CO2 and diols using CeO2 catalyst and 2-cyanopyridine promotor, providing the alternating cooligomers in high diol-based yield (up to 99%) and selectivity (up to >99%). This catalyst system is applicable to various diols including linear C4-C10 α,ω-diols to provide high yields of the corresponding cooligomers, which cannot be obtained by well-known methods such as copolymerization of CO2 and cyclic ethers and ring-opening polymerization of cyclic carbonates. This process provides us a facile synthesis method for versatile polycarbonates from various diols and CO2 owing to simplicity of diols modification.

  5. A cost effective CO2 strategy

    DEFF Research Database (Denmark)

    by the Ministry of Transport, with the Technical University of Denmark as one of the main contributors. The CO2-strategy was to be based on the principle of cost-effectiveness. A model was set up to assist in the assessment. The model consists of a projection of CO2-emissions from road and rail modes from 2020......, a scenario-part and a cost-benefit part. Air and sea modes are not analyzed. The model adopts a bottom-up approach to allow a detailed assessment of transport policy measures. Four generic areas of intervention were identified and the likely effect on CO2 emissions, socioeconomic efficiency and other...... are evaluated according to CO2 reduction potential and according to the ‘shadow price’ on a reduction of one ton CO2. The shadow price reflects the costs (and benefits) of the different measures. Comparing the measures it is possible to identify cost effective measures, but these measures are not necessarily...

  6. Investigation into optimal CO2 concentration for CO2 capture from aluminium production

    OpenAIRE

    Mathisen, Anette; Sørensen, Henriette; Melaaen, Morten Christian; Müller, Gunn-Iren

    2013-01-01

    Capture of CO2 from aluminum production has been simulated using Aspen Plus and Aspen Hysys. The technology used for aluminum production is the Hall-Héroult and the current cell design necessitates that large amounts of false air is supplied to the cells. This results in a CO2 concentration in the process gas at around 1 vol%, which is considered uneconomical for CO2 capture. Therefore, the aim of this investigation is to evaluate the CO2 capture from aluminum production when the process g...

  7. CO2 and HCO3- uptake in marine diatoms acclimated to different CO2 concentrations.

    OpenAIRE

    Burkhardt, S.; Amoroso, G.; Riebesell, Ulf

    2001-01-01

    Rates of cellular uptake of CO2 and HCO3- during steady-state photosynthesis were measured in the marine diatoms Thalassiosira weissflogii and Phaeodactylum tricornutum, acclimated to CO2 partial pressures of 36, 180, 360, and 1,800 ppmv. In addition, in vivo activity of extracellular (eCA) and intracellular (iCA) carbonic anhydrase was determined in relation to CO2 availability. Both species responded to diminishing CO2 supply with an increase in eCA and iCA activity. In P. tricornutum, eCA ...

  8. Surface CO2 leakage during the first shallow subsurface CO2release experiment

    Energy Technology Data Exchange (ETDEWEB)

    Lewicki, J.L.; Oldenburg, C.; Dobeck, L.; Spangler, L.

    2007-09-15

    A new field facility was used to study CO2 migrationprocesses and test techniques to detect and quantify potential CO2leakage from geologic storage sites. For 10 days starting 9 July 2007,and for seven days starting 5 August 2007, 0.1 and 0.3 t CO2 d-1,respectively, were released from a ~;100-m long, sub-water table (~;2.5-mdepth) horizontal well. The spatio-temporal evolution of leakage wasmapped through repeated grid measurements of soil CO2 flux (FCO2). Thesurface leakage onset, approach to steady state, and post-release declinematched model predictions closely. Modeling suggested that minimal CO2was taken up by groundwater through dissolution, and CO2 spread out ontop of the water table. FCO2 spatial patterns were related to well designand soil physical properties. Estimates of total CO2 discharge along withsoil respiration and leakage discharge highlight the influence ofbackground CO2 flux variations on detection of CO2 leakagesignals.

  9. Measuring Nitrous Oxide Mass Transfer into Non-Aqueous CO2BOL CO2 Capture Solvents

    Energy Technology Data Exchange (ETDEWEB)

    Whyatt, Greg A.; Freeman, Charles J.; Zwoster, Andy; Heldebrant, David J.

    2016-03-28

    This paper investigates CO2 absorption behavior in CO2BOL solvents by decoupling the physical and chemical effects using N2O as a non-reactive mimic. Absorption measurements were performed using a wetted-wall contactor. Testing was performed using a “first generation” CO2 binding organic liquid (CO2BOL), comprised of an independent base and alcohol. Measurements were made with N2O at a lean (0.06 mol CO2/mol BOL) and rich (0.26 mol CO2/mol BOL) loading, each at three temperatures (35, 45 and 55 °C). Liquid-film mass transfer coefficients (kg') were calculated by subtracting the gas film resistance – determined from a correlation from literature – from the overall mass transfer measurement. The resulting kg' values for N2O in CO2BOLs were found to be higher than that of 5 M aqueous MEA under comparable conditions, which is supported by published measurements of Henry’s coefficients for N2O in various solvents. These results suggest that the physical solubility contribution for CO2 absorption in CO2BOLs is greater than that of aqueous amines, an effect that may pertain to other non-aqueous solvents.

  10. Light-duty vehicle CO2 targets consistent with 450 ppm CO2 stabilization.

    Science.gov (United States)

    Winkler, Sandra L; Wallington, Timothy J; Maas, Heiko; Hass, Heinz

    2014-06-01

    We present a global analysis of CO2 emission reductions from the light-duty vehicle (LDV) fleet consistent with stabilization of atmospheric CO2 concentration at 450 ppm. The CO2 emission reductions are described by g CO2/km emission targets for average new light-duty vehicles on a tank-to-wheel basis between 2010 and 2050 that we call CO2 glide paths. The analysis accounts for growth of the vehicle fleet, changing patterns in driving distance, regional availability of biofuels, and the changing composition of fossil fuels. New light-duty vehicle fuel economy and CO2 regulations in the U.S. through 2025 and in the EU through 2020 are broadly consistent with the CO2 glide paths. The glide path is at the upper end of the discussed 2025 EU range of 68-78 g CO2/km. The proposed China regulation for 2020 is more stringent than the glide path, while the 2017 Brazil regulation is less stringent. Existing regulations through 2025 are broadly consistent with the light-duty vehicle sector contributing to stabilizing CO2 at approximately 450 ppm. The glide paths provide long-term guidance for LDV powertrain/fuel development. PMID:24798684

  11. CO2/water interfacial tensions under pressure and temperature conditions of CO2 geological storage

    International Nuclear Information System (INIS)

    CO2 storage in aquifers and depleted hydrocarbon reservoirs is one of the most promising options for reducing CO2 atmospheric concentration. However, its implementation in a given reservoir requires demonstration that CO2 leakage through the reservoir seal (caprock) is extremely limited. One possible cause of rapid leakage is capillary failure of the caprock, which is to a large extent controlled by the CO2/water interfacial tension (IFT). This paper presents pendant drop measurements of IFTs between water and CO2 in a range of temperatures (308-383 K) and pressures (5-45 MPa) relevant to CO2 storage in deep geological formations. Phase densities were measured simultaneously, allowing precise IFT determinations. Increasing the pressure along a given isotherm, IFTs were observed to decrease sharply, then to level off and reach, for pressures above 20 MPa, a pseudo-plateau that decreases slightly with temperature, from around 30 mN/m at 308 K to 23 mN/m at 383 K. The presence of salt (20 g/l NaCl) in the water phase has a negligible effect on the IFT. An important conclusion for CO2 storage is that CO2/brine IFTs have low but reasonable values (higher than 20 mN/m) even at the highest pressures and temperatures examined, and that, neglecting all other possible effects, CO2 storage can, therefore, be considered even in deep geological formations

  12. Carbon monoxide : A quantitative tracer for fossil fuel CO2?

    NARCIS (Netherlands)

    Gamnitzer, Ulrike; Karstens, Ute; Kromer, Bernd; Neubert, Rolf E. M.; Meijer, Harro A. J.; Schroeder, Hartwig; Levin, Ingeborg

    2006-01-01

    Carbon monoxide (CO), carbon dioxide (CO2), and radiocarbon ((CO2)-C-14) measurements have been made in Heidelberg from 2001 to 2004 in order to determine the regional fossil fuel CO2 component and to investigate the application of CO as a quantitative tracer for fossil fuel CO2 (CO2(foss)). The obs

  13. Technologies and possibilities for CO2 capture and storage

    International Nuclear Information System (INIS)

    In the form of overhead sheets an overview is given of the title subject, focusing on the need for deep reductions in greenhouse gas emissions, the portfolio of options for reducing emissions; sources of CO2; stages of the process (capture of CO2, transport of CO2, geological storage of CO2); and performances and costs of CO2 capture and storage (CCS)

  14. The idea of global CO2 trade

    International Nuclear Information System (INIS)

    The US has been criticized for wanting to earn a fortune on a global CO2 market. However, compared to the situation without trade and provided that such a market is designed so that it does not pay to cheat, a global CO2 market may provide the world with an epoch-making means of cost-effective control which can solve future global environmental problems. The economic gains from 'hot air' distributions of permits and CO2 trade make the system politically attractive to potential participants. For example, vital financial subsidies from the EU to Eastern Europe are to be expected. It will probably not pay to cheat if quotas are renewed periodically by the UN. Cheating countries are then to be excluded from further profitable trade. Also, a periodical renewal of permits makes it possible to tighten target levels in the future

  15. Sequestration of CO2 by concrete carbonation.

    Science.gov (United States)

    Galan, Isabel; Andrade, Carmen; Mora, Pedro; Sanjuan, Miguel A

    2010-04-15

    Carbonation of reinforced concrete is one of the causes of corrosion, but it is also a way to sequester CO2. The characteristics of the concrete cover should ensure alkaline protection for the steel bars but should also be able to combine CO2 to a certain depth. This work attempts to advance the knowledge of the carbon footprint of cement. As it is one of the most commonly used materials worldwide, it is very important to assess its impact on the environment. In order to quantify the capacity of cement based materials to combine CO2 by means of the reaction with hydrated phases to produce calcium carbonate, Thermogravimetry and the phenolphthalein indicator have been used to characterize several cement pastes and concretes exposed to different environments. The combined effect of the main variables involved in this process is discussed. The moisture content of the concrete seems to be the most influential parameter. PMID:20225850

  16. CO2 sequestration in basalts: laboratory measurements

    Science.gov (United States)

    Otheim, L. T.; Adam, L.; van Wijk, K.; McLing, T. L.; Podgorney, R. K.

    2010-12-01

    Geologic sequestration of CO2 is proposed as the only promising large-scale method to help reduce CO2 gas emission by its capture at large point sources and subsequent long-term storage in deep geologic formations. Reliable and cost-effective monitoring will be important aspect of ensuring geological sequestration is a safe, effective, and acceptable method for CO2 emissions mitigation. Once CO2 injection starts, seismic methods can be used to monitor the migration of the carbon dioxide plume. To calibrate changes in rock properties from field observations, we propose to first analyze changes in elastic properties on basalt cores. Carbon dioxide sequestration in basalt rocks results in fluid substitution and mixing of CO2 with water and rock mineralizations. Carbon dioxide sequestration in mafic rocks creates reactions such as Mg2SiO 4 + CaMgSi2O 6 + 4CO2 = Mg 3Ca(CO 3) 4 + 3SiO2 whereby primary silicate minerals within the basalt react with carbonic acid laden water to creating secondary carbonate minerals and silicates. Using time-lapse laboratory scale experiments, such as laser generated ultrasonic wave propagation; it is possible to observe small changes in the physical properties of a rock. We will show velocity and modulus measurements on three basalt core samples for different saturation. The ultimate goal of the project is to track seismic changes due to fluid substitution and mineralization. The porosity of our basalts ranges from 8% to 12%, and the P-wave velocity increases by 20% to 40% from dry to water saturated conditions. Petrographic analysis (CT-scans, thin sections, XRF, XRf) will aid in the characterization of the mineral structure in these basalts and its correlation to seismic properties changes resulting from fluid substitution and mineralization.

  17. CO2 Orbital Trends in Comets

    Science.gov (United States)

    Kelley, Michael; Bodewits, Dennis; Feaga, Lori; Knight, Matthew; McKay, Adam; Snodgrass, Colin; Wooden, Diane

    2016-08-01

    Carbon dioxide is a primary volatile in comet nuclei, and potentially a major contributor to comet activity (i.e., the process of mass loss). However, CO2 cannot be observed directly from the ground, and past surveys of this molecule in comets were limited to space-borne snapshot observations. This situation limits our understanding of the behavior of CO2 in comets, and its role in driving comet mass loss. To address this deficiency, we were awarded a Cy11 Spitzer program designed to quantify the production rate of CO2 on >month-long timescales for 21 comets. We request an additional 269~hr in Cy13 to complete the Spitzer portion of our survey, and to add three more comets (46P/Wirtanen and 2 Target of Opportunity Oort cloud comets). Our survey is designed to probe the orbital trends of CO2 production in the comet population. We aim to: 1) examine the role of CO2 in the persistent post-perihelion activity observed in Jupiter-family comets; 2) measure the seasonal variations of CO2/H2O as a proxy for nucleus heterogeneity, when possible; 3) search for orbital trends sensitive to cumulative insolation as a proxy for nucleus layering; and 4) examine how Oort cloud comets evolve by comparing dynamically new and old targets. The final data set will allow us to investigate the effects of heating on the evolution of comets, if nucleus structures can be inferred through activity, and set the stage for JWST investigations into comet activity and composition.

  18. CO2 capture research in the Netherlands

    OpenAIRE

    Meerman, J.C.; Kuramochi, T.; van Egmond, S.

    2008-01-01

    The global climate is changing due to human activities. This human‑induced climate change is mainly caused by global emissions of carbon dioxide (CO2) into the atmosphere. Most scientists agree that in order to mitigate climate change, by 2050, global CO2 emissions must be reduced by at least 50% compared to their 1990 level. Fossil fuels, however, are expected to continue playing a dominant role in the world energy supply far into this century. As yet, the combined effect of improving energy...

  19. 10 MW Supercritical CO2 Turbine Test

    Energy Technology Data Exchange (ETDEWEB)

    Turchi, Craig

    2014-01-29

    The Supercritical CO2 Turbine Test project was to demonstrate the inherent efficiencies of a supercritical carbon dioxide (s-CO2) power turbine and associated turbomachinery under conditions and at a scale relevant to commercial concentrating solar power (CSP) projects, thereby accelerating the commercial deployment of this new power generation technology. The project involved eight partnering organizations: NREL, Sandia National Laboratories, Echogen Power Systems, Abengoa Solar, University of Wisconsin at Madison, Electric Power Research Institute, Barber-Nichols, and the CSP Program of the U.S. Department of Energy. The multi-year project planned to design, fabricate, and validate an s-CO2 power turbine of nominally 10 MWe that is capable of operation at up to 700°C and operates in a dry-cooled test loop. The project plan consisted of three phases: (1) system design and modeling, (2) fabrication, and (3) testing. The major accomplishments of Phase 1 included: Design of a multistage, axial-flow, s-CO2 power turbine; Design modifications to an existing turbocompressor to provide s-CO2 flow for the test system; Updated equipment and installation costs for the turbomachinery and associated support infrastructure; Development of simulation tools for the test loop itself and for more efficient cycle designs that are of greater commercial interest; Simulation of s-CO2 power cycle integration into molten-nitrate-salt CSP systems indicating a cost benefit of up to 8% in levelized cost of energy; Identification of recuperator cost as a key economic parameter; Corrosion data for multiple alloys at temperatures up to 650ºC in high-pressure CO2 and recommendations for materials-of-construction; and Revised test plan and preliminary operating conditions based on the ongoing tests of related equipment. Phase 1 established that the cost of the facility needed to test the power turbine at its full power and temperature would exceed the planned funding for Phases 2 and 3. Late

  20. Chilled Ammonia Process for CO2 Capture

    DEFF Research Database (Denmark)

    Darde, Victor Camille Alfred; Thomsen, Kaj; Well, Willy J.M. van;

    2010-01-01

    The chilled ammonia process absorbs the CO2 at low temperature (2–10°C). The heat of absorption of carbon dioxide by ammonia is significantly lower than for amines. In addition, degradation problems can be avoided and a high carbon dioxide capacity is achieved. Hence, this process shows good...... pressure up to 100bars. The results show that solid phases consisting of ammonium carbonate and bicarbonate are formed in the absorber. The heat requirements in the absorber and in the desorber have been studied. The enthalpy calculations show that a heat requirement for the desorber lower than 2GJ/ton CO2...

  1. CO2 laser cutting of natural granite

    Science.gov (United States)

    Riveiro, A.; Mejías, A.; Soto, R.; Quintero, F.; del Val, J.; Boutinguiza, M.; Lusquiños, F.; Pardo, J.; Pou, J.

    2016-01-01

    Commercial black granite boards (trade name: "Zimbabwe black granite") 10 mm thick, were successfully cut by a 3.5 kW CO2 laser source. Cutting quality, in terms of kerf width and roughness of the cut wall, was assessed by means of statistically planned experiments. No chemical modification of the material in the cutting walls was detected by the laser beam action. Costs associated to the process were calculated, and the main factors affecting them were identified. Results reported here demonstrate that cutting granite boards could be a new application of CO2 laser cutting machines provided a supersonic nozzle is used.

  2. Kronikken: Handel og handling med CO2

    DEFF Research Database (Denmark)

    Andersen, M. S.

    2000-01-01

    De fleksible mekanismer i Kyoto-aftalen fortjener indgående overvejelser, ikke kun fordi de giver mulighed for en rabat på CO2-reduktionen, men også fordi de rummer globale og sikkerhedspolitiske dimensioner som er essentielle.......De fleksible mekanismer i Kyoto-aftalen fortjener indgående overvejelser, ikke kun fordi de giver mulighed for en rabat på CO2-reduktionen, men også fordi de rummer globale og sikkerhedspolitiske dimensioner som er essentielle....

  3. 14CO2 fixation pattern of cyanobacteria

    International Nuclear Information System (INIS)

    The 14CO2 fixation pattern of three cyanobacteria in the light and dark were studied. Two different chromatographic methods widely used for separating labelled photosynthetic intermediates were compared. After ethanolic extraction, a rather uniform fixation pattern reflecting mainly the β-carboxylation pathway is obtained for all 3 species. Of the intermediates, glucosylglycerol is specific and high citrulline and low malate contents are fairly specific to cyanobacteria. The composition of the 14CO2 fixation pattern is hardly affected by changes in temperature or light intensity, but it is severely affected by changes in the water potential of the medium. (author)

  4. Capture and Geological Storage of CO2

    International Nuclear Information System (INIS)

    To build on the growing success of the first two international symposia on emission reduction and CO2 capture and geological storage, held in Paris in 2005 and again in 2007, IFP, ADEME and BRGM organised a third event on the same topic the 5-6 November 2009. This time, the focus was on the urgency of industrial deployment. Indeed, the IPCC 4. assessment report indicates that the world must achieve a 50 to 85% reduction in CO2 emissions by 2050 compared to 2000, in order to limit the global temperature increase to around 2 deg. C. Moreover, IPCC stresses that a 'business as usual' scenario could lead to a temperature increase of between 4 deg. C to 7 deg. C across the planet. The symposium was organized in 4 sessions: Session I - Regulatory framework and strategies for enabling CCS deployment: - CCS: international status of political, regulatory and financing issues (Tom Kerr, IEA); - EC regulatory framework (Scott Brockett, European Commission, DG ENV); - Canada's investments towards implementation of CCS in Canada (Larry Hegan, Office of Energy Research and Development - Government of Canada); - A power company perspective (Pietro Barbucci, ENEL); - EC CCS demonstration network (Kai Tullius, European Commission, DG TREN); - Strategies and policies for accelerating global CCS deployment (Jesse Scott, E3G); - The global CCS Institute, a major initiative to facilitate the rapid deployment of CCS (Nick Otter, GCCSI); Session II - From pilot to demonstration projects: - Otway project, Australia (David Hilditch, CO2 CRC); - US regional partnerships (Gerald Hill, Southeast Regional Carbon Sequestration Partnership - SECARB); - CCS activities in Brazil (Rodolfo Dino, Petrobras); - Lessons learnt from Ketzin CO2Sink project in Germany (Ruediger Giese, GFZ); - CO2 storage - from laboratory to reality (Niels-Peter Christensen, Vattenfall); - Valuation and storage of CO2: A global project for carbon management in South-East France (Gilles Munier, Geogreen); Session III

  5. Uncertainties in the CO2 buget associated to boundary layer dynamics and CO2-advection

    NARCIS (Netherlands)

    Kaikkonen, J.P.; Pino, D.; Vilà-Guerau de Arellano, J.

    2012-01-01

    The relationship between boundary layer dynamics and carbon dioxide (CO2) budget in the convective boundary layer (CBL) is investigated by using mixed-layer theory. We derive a new set of analytical relations to quantify the uncertainties on the estimation of the bulk CO2 mixing ratio and the inferr

  6. CO2 dispersion modelling over Paris region within the CO2-MEGAPARIS project

    Directory of Open Access Journals (Sweden)

    L. Ammoura

    2012-10-01

    Full Text Available Accurate simulation of the spatial and temporal variability of tracer mixing ratios over urban areas is challenging, but essential in order to utilize CO2 measurements in an atmospheric inverse framework to better estimate regional CO2 fluxes. This study investigates the ability of a high-resolution model to simulate meteorological and CO2 fields around Paris agglomeration, during the March field campaign of the CO2-MEGAPARIS project. The mesoscale atmospheric model Meso-NH, running at 2 km horizontal resolution, is coupled with the Town-Energy Balance (TEB urban canopy scheme and with the Interactions between Soil, Biosphere and Atmosphere CO2-reactive (ISBA-A-gs surface scheme, allowing a full interaction of CO2 between the surface and the atmosphere. Statistical scores show a good representation of the Urban Heat Island (UHI and urban-rural contrasts. Boundary layer heights (BLH at urban, sub-urban and rural sites are well captured, especially the onset time of the BLH increase and its growth rate in the morning, that are essential for tall tower CO2 observatories. Only nocturnal BLH at sub-urban sites are slightly underestimated a few nights, with a bias less than 50 m. At Eiffel tower, the observed spikes of CO2 maxima occur every morning exactly at the time at which the Atmospheric Boundary Layer (ABL growth reaches the measurement height. The timing of the CO2 cycle is well captured by the model, with only small biases on CO2 concentrations, mainly linked to the misrepresentation of anthropogenic emissions, as the Eiffel site is at the heart of trafic emission sources. At sub-urban ground stations, CO2 measurements exhibit maxima at the beginning and at the end of each night, when the ABL is fully contracted, with a very strong spatio-temporal variability. The CO2 cycle at these sites is generally well reproduced by the model, even if some biases on the nocturnal maxima appear in the Paris plume parly due to small errors on the vertical

  7. A cross-association model for CO2-methanol and CO2-ethanol mixtures

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    A cross-association model was proposed for CO2-alcohol mixtures based on the statistical associating fluid theory (SAFT).CO2 was treated as a pseudo-associating molecule and both the self-association between alcohol hydroxyls and the cross-association between CO2 and alcohol hydroxyls were considered.The equilibrium properties from low temperature-pressure to high temperature-pressure were investigated using this model.The calculated p-x and p-p diagrams of CO2-methanol and CO2-ethanol mixtures agreed with the experimental data.The results showed that when the cross-association was taken into account for Helmholtz free energy,the calculated equilibrium properties could be significantly improved,and the error prediction of the three phase equilibria and triple points in low temperature regions could be avoided.

  8. Flash scanning the CO2 laser: a revival of the CO2 laser in plastic surgery

    Science.gov (United States)

    Lach, Elliot

    1994-09-01

    The CO2 laser has broad clinical application yet also presents a number of practical disadvantages. These drawbacks have limited the success and utilization of this laser in plastic surgery. Flashscanner technology has recently been used for char-free CO2 laser surgery of the oropharynx, the external female genital tract, and perirectal mucosa. A commercially available optomechanical flashscanner unit `Swiftlase,' was adapted to a CO2 laser and used for treatment in numerous plastic surgical applications. Conditions and situations that were treated in this study included generalized neurofibromatosis, tuberous sclerosis, rhinophyma, viral warts, breast reconstruction, and deepithelialization prior to microsurgery or local flap transfer and/or skin graft placement. There were no significant wound healing complications. Some patients previously sustained undue scarring from conventional CO2 laser surgery. Conservative, primarily ablative CO2 laser surgery with the Swiftlase has usefulness for treatment of patients in plastic surgery including those that were previously unsuccessfully treated.

  9. Carbon Dioxide Laser Absorption Spectrometer (CO2LAS) Aircraft Measurements of CO2

    Science.gov (United States)

    Christensen, Lance E.; Spiers, Gary D.; Menzies, Robert T.; Jacob, Joseph C.; Hyon, Jason

    2011-01-01

    The Jet Propulsion Laboratory Carbon Dioxide Laser Absorption Spectrometer (CO2LAS) utilizes Integrated Path Differential Absorption (IPDA) at 2.05 microns to obtain CO2 column mixing ratios weighted heavily in the boundary layer. CO2LAS employs a coherent detection receiver and continuous-wave Th:Ho:YLF laser transmitters with output powers around 100 milliwatts. An offset frequency-locking scheme coupled to an absolute frequency reference enables the frequencies of the online and offline lasers to be held to within 200 kHz of desired values. We describe results from 2009 field campaigns when CO2LAS flew on the Twin Otter. We also describe spectroscopic studies aimed at uncovering potential biases in lidar CO2 retrievals at 2.05 microns.

  10. The Li–CO2 battery: a novel method for CO2 capture and utilization

    KAUST Repository

    Xu, Shaomao

    2013-01-01

    We report a novel primary Li-CO2 battery that consumes pure CO2 gas as its cathode. The battery exhibits a high discharge capacity of around 2500 mA h g-1 at moderate temperatures. At 100 °C the discharge capacity is close to 1000% higher than that at 40 °C, and the temperature dependence is significantly weaker for higher surface area carbon cathodes. Ex-situ FTIR and XRD analyses convincingly show that lithium carbonate (Li2CO3) is the main component of the discharge product. The feasibility of similar primary metal-CO2 batteries based on earth abundant metal anodes, such as Al and Mg, is demonstrated. The metal-CO2 battery platform provides a novel approach for simultaneous capturing of CO2 emissions and producing electrical energy. © 2013 The Royal Society of Chemistry.

  11. CO2 removal from biogas by using membrane absorption technology%利用膜吸收技术分离沼气中CO2

    Institute of Scientific and Technical Information of China (English)

    晏水平; 陈竞翱; 艾平; 王媛媛; 张衍林

    2012-01-01

    addition, CO2 removal performance of these three absorbents can be ranked as: MEA>DEA>TEA. The operating conditions were also optimized on the basis of the calculation of regeneration energy consumption factor, where 0.175-0.2 mol/mol lean CO2 loading should be recommended for MEA, and 16.7 L/L gas-liquid ratio may be suitable for DEA. Finally, an economic analysis of CO2 removal from biogas by using membrane absorption process was also put forward in this study. The results showed that the cost of CO2 captured is relatively lower, and when the biogas production increases from 1 000 to 12 000 m3/d, CO2 removal cost can be reduced by about 78.6% to 0.5 Yuan/m3 of biogas. The results can provide references for selection of biogas upgrading technology with high efficiency.

  12. Artificial photosynthesis - CO2 towards methanol

    International Nuclear Information System (INIS)

    The new insight into the problem of carbon dioxide utilization into valuable compound - methanol and then its transformation into fuel is presented. Because the highly endothermic requirements of the reaction of CO2 hydrogenation a photocatalytic route is applied. Combining of the two reactions: water splitting and CO2 hydrogenation using H2O as a source of hydrogen at the same time and place are proposed. The studies over modified TiO2 catalysts supported on Al2O3 were conducted in a self-designed circulated photocatalytic reaction system under at room temperature and constant pressure. Experimental results indicated that the highest yield of the photoreduction of CO2 with H2O were obtained using TiO2 with the active anatase phase modified by Ru and WO3 addition. The conversion was very high - almost 97% of CO2 was transformed mainly into methanol (14%vol.) and into small amount of formic and acetic acid and ester.

  13. Heterotrophic fixation of CO2 in soil

    Czech Academy of Sciences Publication Activity Database

    Šantrůčková, Hana; Bird, M. I.; Elhottová, Dana; Novák, Jaroslav; Picek, T.; Šimek, Miloslav; Tykva, Richard

    2005-01-01

    Roč. 49, č. 2 (2005), s. 218-225. ISSN 0095-3628 R&D Projects: GA ČR(CZ) GA206/02/1036; GA AV ČR(CZ) IAA6066901 Institutional research plan: CEZ:AV0Z60660521 Keywords : heterotrophic fixation * CO2 * soil Subject RIV: EH - Ecology, Behaviour Impact factor: 2.674, year: 2005

  14. Artificial photosynthesis - CO2 towards methanol

    Science.gov (United States)

    Nazimek, D.; Czech, B.

    2011-03-01

    The new insight into the problem of carbon dioxide utilization into valuable compound - methanol and then its transformation into fuel is presented. Because the highly endothermic requirements of the reaction of CO2 hydrogenation a photocatalytic route is applied. Combining of the two reactions: water splitting and CO2 hydrogenation using H2O as a source of hydrogen at the same time and place are proposed. The studies over modified TiO2 catalysts supported on Al2O3 were conducted in a self-designed circulated photocatalytic reaction system under at room temperature and constant pressure. Experimental results indicated that the highest yield of the photoreduction of CO2 with H2O were obtained using TiO2 with the active anatase phase modified by Ru and WO3 addition. The conversion was very high - almost 97% of CO2 was transformed mainly into methanol (14%vol.) and into small amount of formic and acetic acid and ester.

  15. 76 FR 43489 - Deferral for CO2

    Science.gov (United States)

    2011-07-20

    ... dioxide CO 2 e carbon dioxide equivalents EO Executive Order EPA U.S. Environmental Protection Agency FR... as the Tailoring Rule; 75 FR 31514), setting thresholds for GHG emissions that define when permits... bioenergy and other biogenic sources (75 FR 41173). The purpose of this CFI was to request comment...

  16. 76 FR 15249 - Deferral for CO2

    Science.gov (United States)

    2011-03-21

    ... EO Executive Order EPA U.S. Environmental Protection Agency FR Federal Register GHG Greenhouse gas... the NAFO on August 3, 2010, related to the PSD and Title V Greenhouse Gas Tailoring Rule (75 FR 31514... how to calculate a source's GHG emissions in tpy CO 2 e.\\15\\ 75 FR 31514-31608. The Inventory...

  17. Projecting human development and CO2 emissions

    CERN Document Server

    Costa, Luís; Kropp, Jürgen P

    2012-01-01

    We estimate cumulative CO2 emissions during the period 2000 to 2050 from developed and developing countries based on the empirical relationship between CO2 per capita emissions (due to fossil fuel combustion and cement production) and corresponding HDI. In order to project per capita emissions of individual countries we make three assumptions which are detailed below. First, we use logistic regressions to fit and extrapolate the HDI on a country level as a function of time. This is mainly motivated by the fact that the HDI is bounded between 0 and 1 and that it decelerates as it approaches 1. Second, we employ for individual countries the correlations between CO2 per capita emissions and HDI in order to extrapolate their emissions. This is an ergodic assumption. Third, we let countries with incomplete data records evolve similarly as their close neighbors (in the emissions-HDI plane, see Fig. 1 in the main text) with complete time series of CO2 per capita emissions and HDI. Country-based emissions estimates a...

  18. Warming the early Earth - CO2 reconsidered

    CERN Document Server

    Von Paris, P; Grenfell, L; Patzer, B; Hedelt, P; Stracke, B; Trautmann, T; Schreier, F

    2008-01-01

    Despite a fainter Sun, the surface of the early Earth was mostly ice-free. Proposed solutions to this so-called "faint young Sun problem" have usually involved higher amounts of greenhouse gases than present in the modern-day atmosphere. However, geological evidence seemed to indicate that the atmospheric CO2 concentrations during the Archaean and Proterozoic were far too low to keep the surface from freezing. With a radiative-convective model including new, updated thermal absorption coefficients, we found that the amount of CO2 necessary to obtain 273 K at the surface is reduced up to an order of magnitude compared to previous studies. For the late Archaean and early Proterozoic period of the Earth, we calculate that CO2 partial pressures of only about 2.9 mb are required to keep its surface from freezing which is compatible with the amount inferred from sediment studies. This conclusion was not significantly changed when we varied model parameters such as relative humidity or surface albedo, obtaining CO2 ...

  19. Commitment accounting of CO2 emissions

    International Nuclear Information System (INIS)

    The world not only continues to build new coal-fired power plants, but built more new coal plants in the past decade than in any previous decade. Worldwide, an average of 89 gigawatts per year (GW yr–1) of new coal generating capacity was added between 2010 and 2012, 23 GW yr–1 more than in the 2000–2009 time period and 56 GW yr–1 more than in the 1990–1999 time period. Natural gas plants show a similar pattern. Assuming these plants operate for 40 years, the fossil-fuel burning plants built in 2012 will emit approximately 19 billion tons of CO2 (Gt CO2) over their lifetimes, versus 14 Gt CO2 actually emitted by all operating fossil fuel power plants in 2012. We find that total committed emissions related to the power sector are growing at a rate of about 4% per year, and reached 307 (with an estimated uncertainty of 192–439) Gt CO2 in 2012. These facts are not well known in the energy policy community, where annual emissions receive far more attention than future emissions related to new capital investments. This paper demonstrates the potential for ‘commitment accounting’ to inform public policy by quantifying future emissions implied by current investments. (letter)

  20. Managing CO2 emissions in Nigeria

    International Nuclear Information System (INIS)

    The energy resources in Nigeria are nearly equally divided between fossil fuels and biofuels. The increasing pressure on them, following expected increased population growth, may lead to substantial emissions of carbon into the atmosphere. Additionally agricultural and forestry management practices in vogue are those related to savannah burning and rotational bush fallow systems, which have been clearly implicated as important sources of CO2 and trace gases. An integrated model for the prediction of future CO2 emissions based on fossil fuels and biomass fuels requirements, rates of deforestation and other land-use indices is presented. This is further based on trends in population and economic growth up to the year 2025, with a base year in 1988. A coupled carbon cycle-climate model based on the contribution of CO2 and other trace gases is established from the proportions of integrated global warming effects for a 20-year averaging time using the product of global warming potential (GWP) and total emissions. An energy-technology inventory approach to optimal resources management is used as a tool for establishing the future scope of reducing the CO2 emissions through improved fossil fuel energy efficiencies. Scenarios for reduction based on gradual to swift shifts from biomass to fossil and renewable fuels are presented together with expected policy options required to effect them

  1. CO2 emissions of nuclear electricity generation

    International Nuclear Information System (INIS)

    A survey of LCA studies on nuclear electricity generation revealed life cycle CO2 emissions ranging between 3 g/kWhe to 60 g/kWhe and above. Firstly, this paper points out the discrepancies in studies by estimating the CO2 emissions of nuclear power generation. Secondly, the paper sets out to provide critical review of future developments of the fuel cycle for light water reactors and illustrates the impact of uncertainties on the specific CO2 emissions of nuclear electricity generation. Each step in the fuel cycle will be considered and with regard to the CO2 emissions analysed. Thereby different assumptions and uncertainty levels are determined for the nuclear fuel cycle. With the impacts of low uranium ore grades for mining and milling as well as higher burn-up rates future fuel characteristics are considered. Sensitivity analyses are performed for all fuel processing steps, for different technical specifications of light water reactors as well as for further external frame conditions. (authors)

  2. Agriculture waste and rising CO2

    Science.gov (United States)

    Currently, there are many uncertainties concerning agriculture’s role in global environmental change including the effects of rising atmospheric CO2 concentration. A viable and stable world food supply depends on productive agricultural systems, but environmental concerns within agriculture have to...

  3. CO2 bij paprika: meerwaarde en beperkingen

    NARCIS (Netherlands)

    Dieleman, J.A.; Zwinkels, Jeroen; Gelder, de A.; Kuiper, I.; Zwart, de H.F.; Dijk, van C.J.; Dueck, T.A.

    2007-01-01

    Een verhoging van de CO2 concentratie verhoogt de productie van een paprikagewas. Maar rookgassen doseren kan ook negatieve gevolgen hebben voor groei en productkwaliteit doordat er gassen vrijkomen die schadelijk kunnen zijn voor het gewas. In 2007 is een project uitgevoerd dat zich richtte op de m

  4. Climate change and CO2 emission reductions

    International Nuclear Information System (INIS)

    This paper presents the results of an opinion poll performed on a representative sample of 1000 persons about their sensitivity to climate change and to environment protection, their knowledge about technologies which are useful for environment protection, their opinion about geological CO2 sequestration, and technologies to be developed to struggle against climate warming

  5. CO2 emission in the Nordic countries

    International Nuclear Information System (INIS)

    This report is the final one in a research project ''Nordic Energy Market Model'' financed by the Nordic Minister Council. The report contains description of the Nordic electric power markets, their production structure, legislation and taxation policy. Surplus power and its exchange among Nordic countries is discussed. CO2 tax as a means to limit emissions is critically evaluated. (EG)

  6. CO2 laser used in cosmetology

    Science.gov (United States)

    Su, Chenglie

    1993-03-01

    Cases of various kinds of warts, nevi, papillomas, skin angiomas, ephilises, skin vegetation, scars and brandy noses were vaporized and solidified with a 2.5 - 8 W low power CO2 laser with an overall satisfaction rate up to 99.8% and the satisfaction rate for one time 92%.

  7. Entity Ranking in Wikipedia

    CERN Document Server

    Vercoustre, Anne-Marie; Pehcevski, Jovan

    2007-01-01

    The traditional entity extraction problem lies in the ability of extracting named entities from plain text using natural language processing techniques and intensive training from large document collections. Examples of named entities include organisations, people, locations, or dates. There are many research activities involving named entities; we are interested in entity ranking in the field of information retrieval. In this paper, we describe our approach to identifying and ranking entities from the INEX Wikipedia document collection. Wikipedia offers a number of interesting features for entity identification and ranking that we first introduce. We then describe the principles and the architecture of our entity ranking system, and introduce our methodology for evaluation. Our preliminary results show that the use of categories and the link structure of Wikipedia, together with entity examples, can significantly improve retrieval effectiveness.

  8. Latent Structured Ranking

    OpenAIRE

    Weston, Jason; Blitzer, John

    2012-01-01

    Many latent (factorized) models have been proposed for recommendation tasks like collaborative filtering and for ranking tasks like document or image retrieval and annotation. Common to all those methods is that during inference the items are scored independently by their similarity to the query in the latent embedding space. The structure of the ranked list (i.e. considering the set of items returned as a whole) is not taken into account. This can be a problem because the set of top predicti...

  9. Ranking the best instances

    OpenAIRE

    Clémençon, Stéphan; Vayatis, Nicolas

    2007-01-01

    29 pages We formulate the local ranking problem in the framework of bipartite ranking where the goal is to focus on the best instances. We propose a methodology based on the construction of real-valued scoring functions. We study empirical risk minimization of dedicated statistics which involve empirical quantiles of the scores. We first state the problem of finding the best instances which can be cast as a classification problem with mass constraint. Next, we develop special performance m...

  10. CO2 Orbital Trends in Comets

    Science.gov (United States)

    Kelley, Michael; Feaga, Lori; Bodewits, Dennis; McKay, Adam; Snodgrass, Colin; Wooden, Diane

    2014-12-01

    Spacecraft missions to comets return a treasure trove of details of their targets, e.g., the Rosetta mission to comet 67P/Churyumov-Gerasimenko, the Deep Impact experiment at comet 9P/Tempel 1, or even the flyby of C/2013 A1 (Siding Spring) at Mars. Yet, missions are rare, the diversity of comets is large, few comets are easily accessible, and comet flybys essentially return snapshots of their target nuclei. Thus, telescopic observations are necessary to place the mission data within the context of each comet's long-term behavior, and to further connect mission results to the comet population as a whole. We propose a large Cycle 11 project to study the long-term activity of past and potential future mission targets, and select bright Oort cloud comets to infer comet nucleus properties, which would otherwise require flyby missions. In the classical comet model, cometary mass loss is driven by the sublimation of water ice. However, recent discoveries suggest that the more volatile CO and CO2 ices are the likely drivers of some comet active regions. Surprisingly, CO2 drove most of the activity of comet Hartley 2 at only 1 AU from the Sun where vigorous water ice sublimation would be expected to dominate. Currently, little is known about the role of CO2 in comet activity because telluric absorptions prohibit monitoring from the ground. In our Cycle 11 project, we will study the CO2 activity of our targets through IRAC photometry. In conjunction with prior observations of CO2 and CO, as well as future data sets (JWST) and ongoing Earth-based projects led by members of our team, we will investigate both long-term activity trends in our target comets, with a particular goal to ascertain the connections between each comet's coma and nucleus.

  11. Zero CO2 emission SOLRGT power system

    International Nuclear Information System (INIS)

    A novel hybrid power system with zero CO2 emission (ZE-SOLRGT) has been proposed and analyzed in this paper. It consists of a high temperature Brayton-like topping cycle and a high pressure-ratio Rankine-like bottoming cycle, integrated with methane-steam reforming, solar heat-assisted steam generation and CO2 capture and compression. Water is selected to be the working fluid. Solar heat input enhances the steam generation and power output, and reduces fossil fuel consumption. Besides CO2 capture with oxy-fuel combustion and cascade recuperation of turbine exhaust heat, the system is featured with indirect upgrading of low-mid temperature solar heat and cascade release of fossil fuel chemical exergy, which is described by the energy level concept. With nearly 100% CO2 capture, the system attains a net energy efficiency of 50.7% (including consideration of the energy needed for oxygen separation). The cost of generated electricity and the payback period of ZE-SOLRGT are found to be $0.056/kWh and 11.3 years, respectively. The system integration accomplishes the complementary utilization of fossil fuel and solar heat, and attains their high efficiency conversion into electricity. -- Highlights: ► A novel hybrid power system ZE-SOLRGT has been proposed and analyzed. ► The system integrates power generation with methane-steam reforming, solar heat driven steam generation and CO2 capture. ► The system is featured with indirect upgrading of solar heat and cascade release of fossil fuel chemical exergy. ► The system thermodynamic and economic performances have been investigated.

  12. Hierarchical partial order ranking

    International Nuclear Information System (INIS)

    Assessing the potential impact on environmental and human health from the production and use of chemicals or from polluted sites involves a multi-criteria evaluation scheme. A priori several parameters are to address, e.g., production tonnage, specific release scenarios, geographical and site-specific factors in addition to various substance dependent parameters. Further socio-economic factors may be taken into consideration. The number of parameters to be included may well appear to be prohibitive for developing a sensible model. The study introduces hierarchical partial order ranking (HPOR) that remedies this problem. By HPOR the original parameters are initially grouped based on their mutual connection and a set of meta-descriptors is derived representing the ranking corresponding to the single groups of descriptors, respectively. A second partial order ranking is carried out based on the meta-descriptors, the final ranking being disclosed though average ranks. An illustrative example on the prioritisation of polluted sites is given. - Hierarchical partial order ranking of polluted sites has been developed for prioritization based on a large number of parameters

  13. CO2 dispersion modelling over Paris region within the CO2-MEGAPARIS project

    Science.gov (United States)

    Lac, C.; Donnelly, R. P.; Masson, V.; Pal, S.; Riette, S.; Donier, S.; Queguiner, S.; Tanguy, G.; Ammoura, L.; Xueref-Remy, I.

    2013-05-01

    Accurate simulation of the spatial and temporal variability of tracer mixing ratios over urban areas is a challenging and interesting task needed to be performed in order to utilise CO2 measurements in an atmospheric inverse framework and to better estimate regional CO2 fluxes. This study investigates the ability of a high-resolution model to simulate meteorological and CO2 fields around Paris agglomeration during the March field campaign of the CO2-MEGAPARIS project. The mesoscale atmospheric model Meso-NH, running at 2 km horizontal resolution, is coupled with the Town Energy Balance (TEB) urban canopy scheme and with the Interactions between Soil, Biosphere and Atmosphere CO2-reactive (ISBA-A-gs) surface scheme, allowing a full interaction of CO2 modelling between the surface and the atmosphere. Statistical scores show a good representation of the urban heat island (UHI) with stronger urban-rural contrasts on temperature at night than during the day by up to 7 °C. Boundary layer heights (BLH) have been evaluated on urban, suburban and rural sites during the campaign, and also on a suburban site over 1 yr. The diurnal cycles of the BLH are well captured, especially the onset time of the BLH increase and its growth rate in the morning, which are essential for tall tower CO2 observatories. The main discrepancy is a small negative bias over urban and suburban sites during nighttime (respectively 45 m and 5 m), leading to a few overestimations of nocturnal CO2 mixing ratios at suburban sites and a bias of +5 ppm. The diurnal CO2 cycle is generally well captured for all the sites. At the Eiffel tower, the observed spikes of CO2 maxima occur every morning exactly at the time at which the atmospheric boundary layer (ABL) growth reaches the measurement height. At suburban ground stations, CO2 measurements exhibit maxima at the beginning and at the end of each night, when the ABL is fully contracted, with a strong spatio-temporal variability. A sensitivity test without

  14. Using natural CO2 reservoir to constrain geochemical models for CO2 geological sequestration

    International Nuclear Information System (INIS)

    Highlights: • We model mineral alteration in a natural CO2 reservoir. • Field observation data are reproduced by our geochemical models. • This is an effective way to validate models for CO2 geological sequestration. • Thermodynamic and kinetic data of minerals can be constrained. • Conditions of temperature, pressure, and salinity can be confined. - Abstract: Numerical modeling of geochemical transport processes is necessary to investigate long-term CO2 storage in deep saline formations, because aluminosilicate mineral alteration is very slow under ambient deep-formation conditions and is not amenable to experimental study. Geochemical transport modeling can solve many problems and answer questions related to CO2 geological sequestration. The numerical modeling provides valuable insights regarding the physical and chemical consequences of CO2 injection in the subsurface environment. However, the reliability and applicability of the models need to be tested and validated if they are applied for CO2 geological sequestration. Issues on model validations are important if CO2 injection technologies are to be implemented safely, efficiently, and predictably. Validation of geochemical transport models could be different from conventional model validation methods for groundwater flow and solute transport. For the short-term behaviors, the models can be validated using laboratory and field experiments. For the long-term mineral alteration and CO2 sequestration, the natural analogue using high-pressure CO2 reservoirs could be a best way to validate the model. In this paper, a natural CO2 reservoir in southern Songliao Basin of China, which is past accumulations of CO2 in geological formation associated with magmatic or volcanic activity, was selected. Although the length of CO2 exposure and hence the rates of reaction for the natural system is not known in detail, we have shown that it is indeed possible to use observation data of mineral alteration in the natural

  15. CO2 dispersion modelling over Paris region within the CO2-MEGAPARIS project

    Directory of Open Access Journals (Sweden)

    C. Lac

    2013-05-01

    Full Text Available Accurate simulation of the spatial and temporal variability of tracer mixing ratios over urban areas is a challenging and interesting task needed to be performed in order to utilise CO2 measurements in an atmospheric inverse framework and to better estimate regional CO2 fluxes. This study investigates the ability of a high-resolution model to simulate meteorological and CO2 fields around Paris agglomeration during the March field campaign of the CO2-MEGAPARIS project. The mesoscale atmospheric model Meso-NH, running at 2 km horizontal resolution, is coupled with the Town Energy Balance (TEB urban canopy scheme and with the Interactions between Soil, Biosphere and Atmosphere CO2-reactive (ISBA-A-gs surface scheme, allowing a full interaction of CO2 modelling between the surface and the atmosphere. Statistical scores show a good representation of the urban heat island (UHI with stronger urban–rural contrasts on temperature at night than during the day by up to 7 °C. Boundary layer heights (BLH have been evaluated on urban, suburban and rural sites during the campaign, and also on a suburban site over 1 yr. The diurnal cycles of the BLH are well captured, especially the onset time of the BLH increase and its growth rate in the morning, which are essential for tall tower CO2 observatories. The main discrepancy is a small negative bias over urban and suburban sites during nighttime (respectively 45 m and 5 m, leading to a few overestimations of nocturnal CO2 mixing ratios at suburban sites and a bias of +5 ppm. The diurnal CO2 cycle is generally well captured for all the sites. At the Eiffel tower, the observed spikes of CO2 maxima occur every morning exactly at the time at which the atmospheric boundary layer (ABL growth reaches the measurement height. At suburban ground stations, CO2 measurements exhibit maxima at the beginning and at the end of each night, when the ABL is fully contracted, with a strong spatio-temporal variability. A

  16. On the coupled system performance of transcritical CO2 heat pump and rankine cycle

    Science.gov (United States)

    Wang, Hongli; Tian, Jingrui; Hou, Xiujuan

    2013-12-01

    As one of the natural refrigerants, CO2 is a potential substitute for synthesized refrigerants with favorable environmental properties. In order to improve the performance of rankine cycle (RankC), the coupled system cycle (CSC) was designed and the performance was analyzed in this paper, which the CSC is combined by the RankC and the transcritical CO2 heat pump cycle with an expander. Based on thermodynamic principles, the performance analysis platform was designed and the performance analysis was employed. The results show that the average efficiency of the RankC is about 30 %, and the extraction cycle is about 32 %, while the CSC is about 39 %, and the last one is better than the others at the same parameters. With increasing of the boiler feed water temperature, the efficiencies of the three kinds of cycles show increasing trend. With increasing of pressure in conderser-evaporator or outlet temperature of gas cooler, the efficiency of the CSC shows a downward trend. Some fundamental data were obtained for increasing the RankC efficiency by waste heat recovery, and play an active role in improvement the efficiency of power plants.

  17. CO2驱油与埋存研究进展%Advances in CO2 Displacing Oil and CO2 Sequestrated Researches

    Institute of Scientific and Technical Information of China (English)

    陈欢庆; 胡永乐; 田昌炳

    2012-01-01

    The current situation of CO2 displacing oil and CO2 sequestrated researches was reviewed. Nowadays, CO2 displacing oil had got good economic benefits outside and was carried out oil field experiment inside. And CO2 sequestrated researches were in exploring stage all over the world. The key problems in CO2 displacing oil and CO2 sequestrated researches contained five parts, such as enlarging sweep volume of EOR, carrier and medium choice of CO2 sequestrated, the formation damage in the process of CO2 displacing oil, air source, industrial coordination and overall planning. Finally, several development directions of CO2 displacing oil and CO2 sequestrated researches were proposed.%详细介绍了CO2驱油与埋存研究的现状。目前CO2驱油在国外已取得较好的经济效益,在国内正在进行矿场先导试验。而CO2埋存在国内外均处于探索阶段。CO2驱油与埋存研究中存在的问题主要包括提高采收率方面的扩大波及体积等关键问题、CO2埋存介质和方法的选择、CO2驱油对地层的伤害、CO2驱油与埋存的气源问题、CO2驱油与埋存产业协调和整体规划5大方面。指出了该项研究的发展趋势。图2表2参38

  18. Competitive sorption of CO2 and CH4 on coals as a function of maturity and moisture content

    Science.gov (United States)

    Merkel, Alexej; Gensterblum, Yves; Kroos, Bernhard; Littke, Ralf

    2013-04-01

    The competitive sorption of CH4 and CO2 from a two-component gas mixture on coals of different rank and moisture content has been studied at pressures up to 10 MPa. The aim of this study was to assess, the maximum sorption capacity as well as the selectivity of dry and moisturised coals of different rank with respect to sorption of CH4and CO2. The research addresses possible implications on Enhanced Coal Bed Methane (ECBM) recovery projects, where CO2is to be injected into coal seams to increase CH4production rates. The measurements were conducted using a manometric setup with continuous pressure and temperature recording and periodic analysis of gas compositions in the reference cell and the measuring cell throughout the duration of the experiment. Isotherms were determined with a gas mixture containing 70-80% CH4. Three isotherms were measured at three different moisture states for each of the three coal samples of different rank. A significant decrease of total excess sorption capacity was observed with increasing moisture content from the dry sample to the sample moisturised at 53% relative humidity (RH). The initial reduction of sorption capacity decreases with rank. Only a small further decrease occurred from 53% to the 97% RH moisturised coals. The effect of moisture on sorption capacity and selectivity is highly rank-dependent. In all cases the results show a preferential sorption of CO2from a binary CH4/CO2gas mixture at all three moisture states. Sorption capacity increases with rank for all but the dry state and in all cases the sample with the highest maturity shows the highest sorption capacity by far. Selectivity for CO2 decreases with increasing rank of the coal. The results of this study support that from the thermodynamic point of view coals have a tendency to selectively take up CO2under the conditions of ECBM recovery. The selectivity coefficients are important parameters for ECBM modelling and the design of production strategies.

  19. Accelerated carbonation of steel slags using CO2 diluted sources: CO2 uptakes and energy requirements

    OpenAIRE

    Renato eBaciocchi; Giulia eCosta; Alessandra ePolettini; Raffaella ePomi; Alessio eStramazzo; Daniela eZingaretti

    2016-01-01

    This work presents the results of carbonation experiments performed on Basic Oxygen Furnace (BOF) steel slag samples employing gas mixtures containing 40 and 10% CO2 vol. simulating the gaseous effluents of gasification and combustion processes respectively, as well as 100% CO2 for comparison purposes. Two routes were tested, the slurry phase (L/S=5 l/kg, T=100 °C and Ptot=10 bar) and the thin film (L/S =0.3-0.4 l/kg, T=50 °C and Ptot=7-10 bar) routes. For each one, the CO2 uptake achieved as...

  20. Literatuuronderzoek CAM-fotosynthese en CO2-bemesting en CO2-bemesting bij bromelia's

    OpenAIRE

    Marissen, A.; Warmenhoven, M.G.

    2004-01-01

    De ‘normale’ wijze van CO2-opname gebeurt bij de meeste planten overdag, wanneer er licht is om de opgenomen CO2 door middel van fotosynthese direct om te zetten in suikers. Hiervoor is het nodig dat de huidmondjes overdag open staan, ‘s nachts zijn huidmondjes meestal dicht. Via de huidmondjes gaat waterdamp naar buiten, de planten verdampen zo overdag veel meer dan ‘s nachts. Een deel van de Bromeliaceae -soorten hebben zich echter gespecialiseerd in een andere wijze van CO2-opname. In deze...

  1. CO2 capture processes in power plants - Le captage du CO2 dans les centrales thermiques

    OpenAIRE

    Bouallou, Chakib

    2010-01-01

    PDF file available for free at http://pubs.ub.ro/?pg=revues&rev=cscc6&num=201011&vol=1&aid=2975 International audience This review is devoted to assess and compare various processes aiming at recover CO2 from power plants fed with natural gas (NGCC) and pulverized coal (PC). These processes are post combustion CO2 capture using chemical solvents, natural gas reforming for pre-combustion capture and oxy-fuel combustion with cryogenic recovery of CO2. These processes were evaluated to giv...

  2. Multiplex PageRank.

    Science.gov (United States)

    Halu, Arda; Mondragón, Raúl J; Panzarasa, Pietro; Bianconi, Ginestra

    2013-01-01

    Many complex systems can be described as multiplex networks in which the same nodes can interact with one another in different layers, thus forming a set of interacting and co-evolving networks. Examples of such multiplex systems are social networks where people are involved in different types of relationships and interact through various forms of communication media. The ranking of nodes in multiplex networks is one of the most pressing and challenging tasks that research on complex networks is currently facing. When pairs of nodes can be connected through multiple links and in multiple layers, the ranking of nodes should necessarily reflect the importance of nodes in one layer as well as their importance in other interdependent layers. In this paper, we draw on the idea of biased random walks to define the Multiplex PageRank centrality measure in which the effects of the interplay between networks on the centrality of nodes are directly taken into account. In particular, depending on the intensity of the interaction between layers, we define the Additive, Multiplicative, Combined, and Neutral versions of Multiplex PageRank, and show how each version reflects the extent to which the importance of a node in one layer affects the importance the node can gain in another layer. We discuss these measures and apply them to an online multiplex social network. Findings indicate that taking the multiplex nature of the network into account helps uncover the emergence of rankings of nodes that differ from the rankings obtained from one single layer. Results provide support in favor of the salience of multiplex centrality measures, like Multiplex PageRank, for assessing the prominence of nodes embedded in multiple interacting networks, and for shedding a new light on structural properties that would otherwise remain undetected if each of the interacting networks were analyzed in isolation. PMID:24205186

  3. Asset ranking manager (ranking index of components)

    International Nuclear Information System (INIS)

    The Ranking Index of Components (RIC) is an Asset Reliability Manager (ARM), which itself is a Web Enabled front end where plant database information fields from several disparate databases are combined. That information is used to create a specific weighted number (Ranking Index) relating to that components health and risk to the site. The higher the number, the higher priority that any work associated with that component receives. ARM provides site Engineering, Maintenance and Work Control personnel with a composite real time - (current condition) look at the components 'risk of not working' to the plant. Information is extracted from the existing Computerized Maintenance management System (CMMS) and specific site applications and processed nightly. ARM helps to ensure that the most important work is placed into the workweeks and the non value added work is either deferred, frequency changed or deleted. This information is on the web, updated each night, and available for all employees to use. This effort assists the work management specialist when allocating limited resources to the most important work. The use of this tool has maximized resource usage, performing the most critical work with available resources. The ARM numbers are valued inputs into work scoping for the workweek managers. System and Component Engineers are using ARM to identify the components that are at 'risk of failure' and therefore should be placed into the appropriate work week schedule

  4. Combustion of hythane diluted with CO2

    OpenAIRE

    Hraiech Ibtissem; Sautet Jean-Charles; Yon Sébastien; Mhimid Abdallah

    2015-01-01

    With increasing concern about energy shortage and environmental protection, improving engine fuel economy and reducing exhaust emissions have become major research topics in combustion and engine development. Hythane (a blend of hydrogen H2 and natural gas NG) has generated a significant interest as an alternative fuel for the future. This paper describes an experimental study of the effects of CO2 addition on the stability of a turbulent jet diffusion NG-H...

  5. CO2 mitigation in advanced power cycles

    OpenAIRE

    Wolf, Jens

    2004-01-01

    This thesis encompasses CO2 mitigation using three different processes: i) natural gas-fired combined cycle with chemical looping combustion (CLC), ii) trigeneration of electrical power, hydrogen and district heating with extended CLC, iii) steam-based gasification of biomass integrated in an advanced power cycle. In CLC, a solid oxygen carrier circulates between two fluidised-bed reactors and transports oxygen from the combustion air to the fuel; thus, the fuel is not mixed with air and an i...

  6. Continuous CO2 extractor and methods

    Energy Technology Data Exchange (ETDEWEB)

    None listed

    2010-06-15

    The purpose of this CRADA was to assist in technology transfer from Russia to the US and assist in development of the technology improvements and applications for use in the U.S. and worldwide. Over the period of this work, ORNL has facilitated design, development and demonstration of a low-pressure liquid extractor and development of initial design for high-pressure supercritical CO2 fluid extractor.

  7. Continuous CO2 extractor and methods

    International Nuclear Information System (INIS)

    The purpose of this CRADA was to assist in technology transfer from Russia to the US and assist in development of the technology improvements and applications for use in the U.S. and worldwide. Over the period of this work, ORNL has facilitated design, development and demonstration of a low-pressure liquid extractor and development of initial design for high-pressure supercritical CO2 fluid extractor.

  8. The CO2 capture and sequestration plan

    International Nuclear Information System (INIS)

    The CO2 capture and sequestration plan is officially one of the most relevant solution in the world control against the greenhouse gas releases. In spite of the multiplication of the pilot plans, this technology delays however to run up. At the moment, it is always the petroleum and natural gas industries, with the enhanced oil recovery process, which highlight this technology. But, without a modification of the support mechanisms, the chances of succeed of the sector could be compromised. (O.M.)

  9. Sustainable Process Networks for CO2 Conversion

    OpenAIRE

    Frauzem, Rebecca; Kongpanna, P.; Pavarajam, V.; Gani, Rafiqul; Assabumrungrat, S.

    2014-01-01

    According to various organizations, especially the Intergovernmental Panel on Climate Change, global warming is an ever-increasing threat to the environment and poses a problem if not addressed. As a result, efforts are being made across academic and industrial fields to find methods of reducing contributors to global warming, primarily greenhouse gas emissions. Of these, carbon dioxide (CO2) is the largest source and, therefore, the reduction of the amount emitted is primary focus of develop...

  10. Aridity under conditions of increased CO2

    Science.gov (United States)

    Greve, Peter; Roderick, Micheal L.; Seneviratne, Sonia I.

    2016-04-01

    A string of recent of studies led to the wide-held assumption that aridity will increase under conditions of increasing atmospheric CO2 concentrations and associated global warming. Such results generally build upon analyses of changes in the 'aridity index' (the ratio of potential evaporation to precipitation) and can be described as a direct thermodynamic effect on atmospheric water demand due to increasing temperatures. However, there is widespread evidence that contradicts the 'warmer is more arid' interpretation, leading to the 'global aridity paradox' (Roderick et al. 2015, WRR). Here we provide a comprehensive assessment of modeled changes in a broad set of dryness metrics (primarily based on a range of measures of water availability) over a large range of realistic atmospheric CO2 concentrations. We use an ensemble of simulations from of state-of-the-art climate models to analyse both equilibrium climate experiments and transient historical simulations and future projections. Our results show that dryness is, under conditions of increasing atmospheric CO2 concentrations and related global warming, generally decreasing at global scales. At regional scales we do, however, identify areas that undergo changes towards drier conditions, located primarily in subtropical climate regions and the Amazon Basin. Nonetheless, the majority of regions, especially in tropical and mid- to northern high latitudes areas, display wetting conditions in a warming world. Our results contradict previous findings and highlight the need to comprehensively assess all aspects of changes in hydroclimatological conditions at the land surface. Roderick, M. L., P. Greve, and G. D. Farquhar (2015), On the assessment of aridity with changes in atmospheric CO2, Water Resour. Res., 51, 5450-5463

  11. [Voice quality following CO2 laser cordectomy].

    Science.gov (United States)

    Höfler, H; Bigenzahn, W

    1986-11-01

    The voice of patients after CO2 laser cordectomy was evaluated by subjective assessment, registration of voice parameters and sonegraphic classification. The results proved to be closely concordant, the main result being a slight or medium degree of dysphonia. Severe dysphonia or aphonia occurred in about one fifth of patients. This result is somewhat inferior to radiotherapy, but superior to standard translaryngeal cordectomy. Yanagihara's sonegraphic classification of dysphonia is recommendable for future comparative studies. PMID:3807602

  12. Towards Overhauser DNP in supercritical CO2

    Science.gov (United States)

    van Meerten, S. G. J.; Tayler, M. C. D.; Kentgens, A. P. M.; van Bentum, P. J. M.

    2016-06-01

    Overhauser Dynamic Nuclear Polarization (ODNP) is a well known technique to improve NMR sensitivity in the liquid state, where the large polarization of an electron spin is transferred to a nucleus of interest by cross-relaxation. The efficiency of the Overhauser mechanism for dipolar interactions depends critically on fast local translational dynamics at the timescale of the inverse electron Larmor frequency. The maximum polarization enhancement that can be achieved for 1H at high magnetic fields benefits from a low viscosity solvent. In this paper we investigate the option to use supercritical CO2 as a solvent for Overhauser DNP. We have investigated the diffusion constants and longitudinal nuclear relaxation rates of toluene in high pressure CO2. The change in 1H T1 by addition of TEMPO radical was analyzed to determine the Overhauser cross-relaxation in such a mixture, and is compared with calculations based on the Force Free Hard Sphere (FFHS) model. By analyzing the relaxation data within this model we find translational correlation times in the range of 2-4 ps, depending on temperature, pressure and toluene concentration. Such short correlation times may be instrumental for future Overhauser DNP applications at high magnetic fields, as are commonly used in NMR. Preliminary DNP experiments have been performed at 3.4 T on high pressure superheated water and model systems such as toluene in high pressure CO2.

  13. Breadboard CO2 and humidity control system

    Science.gov (United States)

    Boehm, A. M.

    1976-01-01

    A regenerable CO2 and humidity control system is being developed for potential use on shuttle as an alternate to the baseline lithium hydroxide (LiOH)/condensing heat exchanger system. The system utilizes a sorbent material, designated HS-C, to adsorb CO2 and water vapor from the cabin atmosphere. The material is regenerated by exposing it to space vacuum. A half-size breadboard system, utilizing a flight representative HS-C canister, was designed, built, and performance tested to shuttle requirements for total CO2 and total humidity removal. The use of a new chemical matrix material allowed significant optimization of the system design by packing the HS-C chemical into the core of a heat exchanger which is manifolded to form two separate and distinct beds. Breadboard system performance was proven by parametric testing and simulated mission testing over the full range of shuttle crew sizes and metabolic loadings. Vacuum desorption testing demonstrated considerable savings in previously projected shuttle vacuum duct sizing.

  14. Towards Overhauser DNP in supercritical CO2.

    Science.gov (United States)

    van Meerten, S G J; Tayler, M C D; Kentgens, A P M; van Bentum, P J M

    2016-06-01

    Overhauser Dynamic Nuclear Polarization (ODNP) is a well known technique to improve NMR sensitivity in the liquid state, where the large polarization of an electron spin is transferred to a nucleus of interest by cross-relaxation. The efficiency of the Overhauser mechanism for dipolar interactions depends critically on fast local translational dynamics at the timescale of the inverse electron Larmor frequency. The maximum polarization enhancement that can be achieved for (1)H at high magnetic fields benefits from a low viscosity solvent. In this paper we investigate the option to use supercritical CO2 as a solvent for Overhauser DNP. We have investigated the diffusion constants and longitudinal nuclear relaxation rates of toluene in high pressure CO2. The change in (1)H T1 by addition of TEMPO radical was analyzed to determine the Overhauser cross-relaxation in such a mixture, and is compared with calculations based on the Force Free Hard Sphere (FFHS) model. By analyzing the relaxation data within this model we find translational correlation times in the range of 2-4ps, depending on temperature, pressure and toluene concentration. Such short correlation times may be instrumental for future Overhauser DNP applications at high magnetic fields, as are commonly used in NMR. Preliminary DNP experiments have been performed at 3.4T on high pressure superheated water and model systems such as toluene in high pressure CO2. PMID:27082277

  15. Characterization of CO2 leakage into the freshwater body

    DEFF Research Database (Denmark)

    Singh, Ashok; Delfs, Jens Olaf; Shao, H.;

    2013-01-01

    urrent research into CO2 capture and storage is dominated by improving the CO2 storage capacity. In this context, risk related to CO2 leakage is an important issue which may cause environmental problems, particularly when freshwater resources nearby are intruded by the CO2 plume. In this work, the...

  16. Electron Attachment to CO2 Embedded in Superfluid He Droplets

    OpenAIRE

    Postler, Johannes; Vizcaino, Violaine; Denifl, Stephan; Zappa, Fabio; Ralser, Stefan; Daxner, Matthias; Illenberger, Eugen; Scheier, Paul

    2014-01-01

    Electron attachment to CO2 embedded in superfluid He droplets leads to ionic complexes of the form (CO2) n – and (CO2) n O– and, at much lower intensities, He containing ions of the form He m (CO2) n O–. At low energies (

  17. 46 CFR 108.433 - Quantity of CO2: General.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 4 2010-10-01 2010-10-01 false Quantity of CO2: General. 108.433 Section 108.433... Quantity of CO2: General. Each CO2 system must have enough gas to meet the quantity requirements of § 108.439 for the space requiring the greatest amount of CO2....

  18. Natural Analogues of CO2 Geological Storage; Analogos Naturales del Almacenamiento Geologico de CO2

    Energy Technology Data Exchange (ETDEWEB)

    Perez del Villar, L.; Pelayo, M.; Recreo, F.

    2007-07-20

    Geological storage of carbon dioxide is nowadays, internationally considered as the most effective method for greenhouse gas emission mitigation, in order to minimize the global climate change universally accepted. Nevertheless, the possible risks derived of this long-term storage have a direct influence on its public acceptance. Among the favourable geological formations to store CO2, depleted oil and gas fields, deep saline reservoirs, and unamiable coal seams are highlighted. One of the most important objectives of the R and D projects related to the CO2 geological storage is the evaluation of the CO2 leakage rate through the above mentioned geological formations. Therefore, it is absolutely necessary to increase our knowledge on the interaction among CO2, storage and sealing formations, as well as on the flow paths and the physical resistance of the sealing formation. The quantification of the CO2 leakage rate is essential to evaluate the effects on the human and animal health, as well as for the ecosystem and water quality. To achieve these objectives, the study of the natural analogues is very useful in order to know the natural leakage rate to the atmosphere, its flow paths, the physical, chemical and mineralogical modifications due to the long term interaction processes among the CO2 and the storage and sealing formations, as well as the effects on the groundwaters and ecosystems. In this report, we have tried to summarise the main characteristics of the natural reservoirs and surficial sources of CO2, which are both natural analogues of the geological storage and CO2 leakage, studied in EEUU, Europe and Australia. The main objective of this summary is to find the possible applications for long-term risk prediction and for the performance assessment by means of conceptual and numerical modelling, which will allow to validate the predictive models of the CO2 storage behaviour, to design and develop suitable monitoring techniques to control the CO2 behaviour

  19. Strategies for CO2 capture from different CO2 emission sources by vacuum swing adsorption technology☆

    Institute of Scientific and Technical Information of China (English)

    Jianghua Ling; Penny Xiao; Augustine Ntiamoah; Dong Xu; Paul Webley; Yuchun Zhai

    2016-01-01

    Different VSA (Vacuum Swing Adsorption) cycles and process schemes have been evaluated to find suitable process configurations for effectively separating CO2 from flue gases from different industrial sectors. The cycles were studied using an adsorption simulator developed in our research group, which has been suc-cessfully used to predict experimental results over several years. Commercial zeolite APGIII and granular ac-tivated carbon were used as the adsorbents. Three-bed VSA cycles with-and without-product purge and 2-stage VSA systems have been investigated. It was found that for a feed gas containing 15%CO2 (representing flue gas from power plants), high CO2 purities and recoveries could be obtained using a three-bed zeolite APGIII VSA unit for one stage capture, but with more stringent conditions such as deeper vacuum pressures of 1–3 kPa. 2-stage VSA process operated in series allowed us to use simple process steps and operate at more realistic vacuum pressures. With a vacuum pressure of 10 kPa, final CO2 purity of 95.3%with a recov-ery of 98.2%were obtained at specific power consumption of 0.55 MJ·(kg CO2)−1 from feed gas containing 15%CO2. These numbers compare very well with those obtained from a single stage process operating at 1 kPa vacuum pressure. The feed CO2 concentration was very influential in determining the desorption pressure necessary to achieve high separation efficiency. For feed gases containing N30%CO2, a single-stage VSA capture process operating at moderate vacuum pressure and without a product purge, can achieve very high product purities and recoveries.

  20. Brine/CO2 Interfacial Properties and Effects on CO2 Storage in Deep Saline Aquifers

    International Nuclear Information System (INIS)

    It has been long recognized that interfacial interactions (interfacial tension, wettability, capillarity and interfacial mass transfer) govern fluid distribution and behaviour in porous media. Therefore the interfacial interactions between CO2, brine and reservoir oil and/or gas have an important influence on the effectiveness of any CO2 storage operation. There is a lack of experimental data related to interfacial properties for all the geological storage options (oil and gas reservoirs, coal-beds, deep saline aquifers). In the case of deep saline aquifers, there is a gap in data and knowledge of brine-CO2 interfacial properties at storage conditions. More specifically, experimental interfacial tension values and experimental tests in porous media are necessary to better understand the wettability evolution as a function of thermodynamic conditions and it's effects on fluid flow in the porous media. In this paper, a complete set of experimental values of brine-CO2 Interfacial Tension (IFT) at pressure, temperature and salt concentration conditions representative of those of a CO2 storage operation. A correlation is derived from experimental data published in a companion paper [Chalbaud C., Robin M., Lombard J.-M., Egermann P., Bertin H. (2009) Interfacial Tension Measurements and Wettability Evaluation for Geological CO2 Storage, Adv. Water Resour. 32, 1, 1-109] to model IFT values. This paper pays particular attention to core flooding experiments showing that the CO2 partially wets the surface in a Intermediate-Wet (IW) or Oil-Wet (OW) limestone rock. This wetting behavior of CO2 is coherent with observations at the pore scale in glass micro-models and presents a negative impact on the storage capacity of a given site. (authors)

  1. Impact of CO2 Impure stream on a CO2 Storage Reservoir

    Science.gov (United States)

    Segev, R.; Bear, J.; Bensabat, J.

    2013-12-01

    In a CO2 capture and storage (CCS) technology, a stream of CO2, extracted from the gas stream emitted from an industrial plant, is transported to a storage site where it is injected into a deep brine-containing geological reservoir for storage for very long time periods. The injected CO2 may contain various compositions of residual O2, SOx , NOx, and inert gases. In this work, we focus on the impact of the SO2 and its potential to acidify the reservoir brine. The amount of dissolved SO2 is determined by adjusting the Henry coefficient and fugacity coefficient for the mixture that contains CO2 as a major component and SO2. The models show the spreading of the pH level over time in the entire reservoir when different CO2-SO2 mixture compositions are injected. The minimum pH level achieved is 0.35 when 4% SO2 is injected, 1.8 when 2% SO2 is injected and 3.8 when a pure CO2 stream is injected. The model may serve as a tool to predict the influence of SO2 on the initial brine composition and on the initial rock properties. For example, a model result for the pH spreading in the reservoir, in the case of 2%SO2-CO2 injected mixture, is shown below. Fig.1. The pH level at the reservoir bedrock and caprock after 5 years for a 2%SO2-CO2 stream.

  2. CO2 Uptake Model of Biomass Silica Foamed Concrete

    OpenAIRE

    Yee Loon Lee; Heng Boon Koh; Ahmad Tarmizi Abdul Karim; Mia Wimala; C. Ng

    2010-01-01

    The cement industry contributes about 5% to global anthropogenic CO2 emissions. CO2 is emitted from the calcination process of limestone, from combustion of fuels in the kiln, as well as from power generation. A model of CO2 uptake by biomass silica foamed concrete is proposed as a potential mitigation strategy against CO2-emission. The key parameters in the cement production process are defined and the total CO2 emissions are reviewed. A comparison between CO2 emission and CO2...

  3. Comprehensive evaluation of industrial CO2 emission (1989-2004) in Taiwan by input-output structural decomposition

    International Nuclear Information System (INIS)

    Taiwan currently emits approximately 1% of the world's CO2 - ranking it 22nd among nations. Herein, we use the input-output (I-O) structural decomposition method to examine the changes in CO2 emission over a 15-year period. By decomposing the CO2 emission changes into nine factors for the periods of 1989-1994, 1994-1999, and 1999-2004, we have identified the key factors causing the emission changes, as well as the most important trends regarding the industrial development process in Taiwan. The 5-year increment with the largest increase of CO2 emission was that of 1999-2004, due to the rapid increase of electricity consumption. From the decomposition, the industrial energy coefficient and the CO2 emission factors were identified as the most important parameters for the determination of the highway, petrochemical materials, iron and steel, the commercial sector, and electric machinery as the major sources of increased CO2 emission during the past 15 years. From 1989 to 2004, the level of exports and the level of domestic final demand were the largest contributors to the increase in the total increment of CO2 change. During 1989-2004, the industrial energy coefficient and CO2 emission factors, being minimally significant during 1989-1994, became extremely important, joining the domestic final demand and the level of exports factors as the major causes of the increase increment of CO2. This indicates a heavy reliance upon high-energy (and CO2) intensity for Taiwanese industries; therefore, continuous efforts to improve energy intensity and fuel mix toward lower carbon are important for CO2 reduction, especially for the electricity and power generation sectors. Relevant strategies for reducing carbon dioxide emissions from major industries are also highlighted. (author)

  4. Comprehensive evaluation of industrial CO2 emission (1989-2004) in Taiwan by input-output structural decomposition

    International Nuclear Information System (INIS)

    Taiwan currently emits approximately 1% of the world's CO2-ranking it 22nd among nations. Herein, we use the input-output (I-O) structural decomposition method to examine the changes in CO2 emission over a 15-year period. By decomposing the CO2 emission changes into nine factors for the periods of 1989-1994, 1994-1999, and 1999-2004, we have identified the key factors causing the emission changes, as well as the most important trends regarding the industrial development process in Taiwan. The 5-year increment with the largest increase of CO2 emission was that of 1999-2004, due to the rapid increase of electricity consumption. From the decomposition, the industrial energy coefficient and the CO2 emission factors were identified as the most important parameters for the determination of the highway, petrochemical materials, iron and steel, the commercial sector, and electric machinery as the major sources of increased CO2 emission during the past 15 years. From 1989 to 2004, the level of exports and the level of domestic final demand were the largest contributors to the increase in the total increment of CO2 change. During 1989-2004, the industrial energy coefficient and CO2 emission factors, being minimally significant during 1989-1994, became extremely important, joining the domestic final demand and the level of exports factors as the major causes of the increase increment of CO2. This indicates a heavy reliance upon high-energy (and CO2) intensity for Taiwanese industries; therefore, continuous efforts to improve energy intensity and fuel mix toward lower carbon are important for CO2 reduction, especially for the electricity and power generation sectors. Relevant strategies for reducing carbon dioxide emissions from major industries are also highlighted

  5. Dynamic Matrix Rank

    DEFF Research Database (Denmark)

    Frandsen, Gudmund Skovbjerg; Frandsen, Peter Frands

    2009-01-01

    We consider maintaining information about the rank of a matrix under changes of the entries. For n×n matrices, we show an upper bound of O(n1.575) arithmetic operations and a lower bound of Ω(n) arithmetic operations per element change. The upper bound is valid when changing up to O(n0.575) entries...... in a single column of the matrix. We also give an algorithm that maintains the rank using O(n2) arithmetic operations per rank one update. These bounds appear to be the first nontrivial bounds for the problem. The upper bounds are valid for arbitrary fields, whereas the lower bound is valid for...... algebraically closed fields. The upper bound for element updates uses fast rectangular matrix multiplication, and the lower bound involves further development of an earlier technique for proving lower bounds for dynamic computation of rational functions....

  6. Ranking economic history journals

    DEFF Research Database (Denmark)

    Di Vaio, Gianfranco; Weisdorf, Jacob Louis

    2010-01-01

    This study ranks-for the first time-12 international academic journals that have economic history as their main topic. The ranking is based on data collected for the year 2007. Journals are ranked using standard citation analysis where we adjust for age, size and self-citation of journals. We also...... compare the leading economic history journals with the leading journals in economics in order to measure the influence on economics of economic history, and vice versa. With a few exceptions, our results confirm the general idea about what economic history journals are the most influential for economic...... history, and that, although economic history is quite independent from economics as a whole, knowledge exchange between the two fields is indeed going on....

  7. Ranking Economic History Journals

    DEFF Research Database (Denmark)

    Di Vaio, Gianfranco; Weisdorf, Jacob Louis

    This study ranks - for the first time - 12 international academic journals that have economic history as their main topic. The ranking is based on data collected for the year 2007. Journals are ranked using standard citation analysis where we adjust for age, size and self-citation of journals. We...... also compare the leading economic history journals with the leading journals in economics in order to measure the influence on economics of economic history, and vice versa. With a few exceptions, our results confirm the general idea about what economic history journals are the most influential...... for economic history, and that, although economic history is quite independent from economics as a whole, knowledge exchange between the two fields is indeed going on....

  8. Entornos Agroambientales: Almacenes Naturales De Co2.

    Directory of Open Access Journals (Sweden)

    Juan Isidro Sánchez Leyva

    2005-01-01

    Full Text Available Cultivos únicos eternos y la extinción de especies; contaminaciones atmosféricas, edáficas e hídricas; la ampliación del agujero de la capa de Ozono, etc. unido al mal uso de la tierra contribuyen al empobrecimiento de comunidades y naciones. Se evaluaron sistemas de cultivos múltiples como sumideros naturales o bancos de CO2. Y se intercalaron leguminosas por sus conocidos y probados beneficios y otras especies anuales en árboles y arbustos conducidos desde 1988-90 en el macizo montañoso Sagüa-Baracoa, Gran Tierra de Sabaneta, El Salvador y valle Guaso provincia Guantánamo; Calabaza de Sagüa de Tánamo y Mayarí, Holguín. Diseñándose 3 ó 4 réplicas según las variantes y laderas y utilizados rangos múltiples de Newman-Kell (P<1%. Para el cálculo de biomasa vegetal se aplicaron fórmulas midiéndose la necromasa bajo el arbolado y el C orgánico edáfico. Se determinó el valor o índice relativo de biomasa, el índice relativo de banco de CO2 y el potencial mínimo de retención del CO2 en el sistema según la edad del cultivo; observándose el suelo erosionado en el predio mediante simple fórmula propuesta. Se observaron formas ecológicas de labor y cultivo. La canavalia fue el cultivo más efectivo considerando la respuesta del C edáfico. Se tuvo en cuenta la productividad y el banco de CO2 por el efecto positivo de ambos factores sobre el medio y dada la relevancia creciente de la reducción de las emisiones de CO2, a la vez que se evita la sobre-explotación y la deforestación. Se significó la necesidad de fajas interarboladas en monocultivos anuales.

  9. Process-dependent residual trapping of CO2 in sandstone

    Science.gov (United States)

    Zuo, Lin; Benson, Sally M.

    2014-04-01

    This paper demonstrates that the nature and extent of residual CO2 trapping depend on the process by which the CO2 phase is introduced into the rock. We compare residual trapping of CO2 in Berea Sandstone by imbibing water into a core containing either exsolved CO2 or CO2 introduced by drainage. X-ray computed tomography measurements are used to map the spatial distribution of CO2 preimbibition and postimbibition. Unlike during drainage where the CO2 distribution is strongly influenced by the heterogeneity of the rock, the distribution of exsolved CO2 is comparatively uniform. Postimbibition, the CO2 distribution retained the essential features for both the exsolved and drainage cases, but twice as much residual trapping is observed for exsolved CO2 even with similar preimbibition gas saturations. Residually trapped exsolved gas also disproportionately reduced water relative permeability. Development of process-dependent parameterization will help better manage subsurface flow processes and unlock benefits from gas exsolution.

  10. CO2 capture by gas hydrate crystallization: Application on the CO2-N2 mixture

    International Nuclear Information System (INIS)

    CO2 capture and sequestration represent a major industrial and scientific challenge of this century. There are different methods of CO2 separation and capture, such as solid adsorption, amines adsorption and cryogenic fractionation. Although these processes are well developed at industrial level, they are energy intensive. Hydrate formation method is a less energy intensive and has an interesting potential to separate carbon dioxide. Gas hydrates are Document crystalline compounds that consist of hydrogen bonded network of water molecules trapping a gas molecule. Gas hydrate formation is favored by high pressure and low temperature. This study was conducted as a part of the SECOHYA ANR Project. The objective is to study the thermodynamic and kinetic conditions of the process to capture CO2 by gas hydrate crystallization. Firstly, we developed an experimental apparatus to carry out experiments to determine the thermodynamic and kinetic formation conditions of CO2-N2 gas hydrate mixture in water as liquid phase. We showed that the operative pressure may be very important and the temperature very low. For the feasibility of the project, we used TBAB (Tetrabutylammonium Bromide) as thermodynamic additive in the liquid phase. The use of TBAB may reduce considerably the operative pressure. In the second part of this study, we presented a thermodynamic model, based on the van der Waals and Platteeuw model. This model allows the estimation of thermodynamic equilibrium conditions. Experimental equilibrium data of CO2-CH4 and CO2-N2 mixtures are presented and compared to theoretical results. (author)

  11. Recycling CO 2 ? Computational Considerations of the Activation of CO 2 with Homogeneous Transition Metal Catalysts

    KAUST Repository

    Drees, Markus

    2012-08-10

    Faced with depleting fossil carbon sources, the search for alternative energy carriers and energy storage possibilities has become an important issue. Nature utilizes carbon dioxide as starting material for storing sun energy in plant hydrocarbons. A similar approach, storing energy from renewable sources in chemical bonds with CO 2 as starting material, may lead to partial recycling of CO 2 created by human industrial activities. Unfortunately, currently available routes for the transformation of CO 2 involve high temperatures and are often not selective. With the development of more sophisticated methods and better software, theoretical studies have become both increasingly widespread and useful. This concept article summarizes theoretical investigations of the current state of the feasibility of CO 2 activation with molecular transition metal catalysts, highlighting the most promising reactions of CO 2 with olefins to industrially relevant acrylic acid/acrylates, and the insertion of CO 2 into metal-element bonds, particularly for the synthesis of cyclic carbonates and polymers. Rapidly improving computational power and methods help to increase the importance and accuracy of calculations continuously and make computational chemistry a useful tool helping to solve some of the most important questions for the future. © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  12. CO2 Sequestration within Spent Oil Shale

    Science.gov (United States)

    Foster, H.; Worrall, F.; Gluyas, J.; Morgan, C.; Fraser, J.

    2013-12-01

    Worldwide deposits of oil shales are thought to represent ~3 trillion barrels of oil. Jordanian oil shale deposits are extensive and of high quality, and could represent 100 billion barrels of oil, leading to much interest and activity in the development of these deposits. The exploitation of oil shales has raised a number of environmental concerns including: land use, waste disposal, water consumption, and greenhouse gas emissions. The dry retorting of oil shales can overcome a number of the environmental impacts, but this leaves concerns over management of spent oil shale and CO2 production. In this study we propose that the spent oil shale can be used to sequester CO2 from the retorting process. Here we show that by conducting experiments using high pressure reaction facilities, we can achieve successful carbonation of spent oil shale. High pressure reactor facilities in the Department of Earth Sciences, Durham University, are capable of reacting solids with a range of fluids up to 15 MPa and 350°C, being specially designed for research with supercritical fluids. Jordanian spent oil shale was reacted with high pressure CO2 in order to assess whether there is potential for sequestration. Fresh and reacted materials were then examined by: Inductively Coupled Plasma Mass Spectrometry (ICP-MS), Thermogravimetric Analysis (TGA), X-Ray Fluorescence (XRF) and X-Ray Diffraction (XRD) methods. Jordanian spent oil shale was found to sequester up to 5.8 wt % CO2, on reacting under supercritical conditions, which is 90% of the theoretical carbonation. Jordanian spent oil shale is composed of a large proportion of CaCO3, which on retorting decomposes, forming CaSO4 and Ca-oxides which are the focus of carbonation reactions. A factorially designed experiment was used to test different factors on the extent of carbonation, including: pressure; temperature; duration; and the water content. Analysis of Variance (ANOVA) techniques were then used to determine the significance of

  13. Fractional Cointegration Rank Estimation

    OpenAIRE

    Lasak, K.A.; Velasco, C

    2014-01-01

    This discussion paper led to a publication in the Journal of Business & Economic Statistics , 2015, 33(2), 241-254. We consider cointegration rank estimation for a p-dimensional Fractional Vector Error Correction Model. We propose a new two-step procedure which allows testing for further long-run equilibrium relations with possibly different persistence levels. The first step consists in estimating the parameters of the model under the null hypothesis of the cointegration rank r=1,2,…,p-1. Th...

  14. Monitoring of Geological CO2, based on Wireless Sensor Networks

    OpenAIRE

    Ms. Wagh Sushama Mohan*; Prof. Mr. Devi R.J.

    2014-01-01

    Carbon Capture and Storage (CCS), also known as Carbon Capture and Sequestration, includes geological storage CO2. Safe, long-term geological storage (sequestration) of CO2 also requires a continuous monitoring system to detect CO2 leakage from reservior. This paper gives details about a remote carbon dioxide (CO2) concentration monitoring system developed, based on the technologies of wireless sensor networks, in allusion to the gas leakage monitoring requirement for CO2 capture ...

  15. THERMODYNAMIC ANALYSIS OF CO2 DIRECT HYDROGENATION REACTIONS

    Institute of Scientific and Technical Information of China (English)

    Cao Fahai; Liu Dianhua; Hou Qiushi; Fang Dingye

    2001-01-01

    CO2 hydrogenation is one of important routes for the activation and effective utilization of CO2. In this paper, eighteen CO2 direct hydrogenation reactions are listed and their reaction heats and equilibrium constants are calculated. On the assumption that the reactions of CO2 and H2 are in stoichiometric ratio and the amount of whole reactants is one mole, the equilibrium conversions of CO2 are obtained.

  16. Monitoring CO2 behaviour during injection into reservoir sandstone

    OpenAIRE

    Tran, Truong Xuan

    2015-01-01

    Storing CO2 in deep subsurface aquifers is considered to be a good solution for reducing the increasing atmospheric emissions of CO2. To mitigate the possibility of stored CO2 leaking out to the atmosphere, geophysical monitoring techniques are applied. These techniques must be able to detect small and big changes in CO2 saturation. In this thesis acoustic and electrical resistivity measurement will be used to detect and monitor the injection of CO2 into three brine saturated samples. Two san...

  17. CO2 and energy France and world indicators 2007

    International Nuclear Information System (INIS)

    In the framework of a sustainable development, the carbon dioxide is a very controlled greenhouse effect gases to limit the climatic change. This paper presents and explains the greenhouse effect, the consequences of the climatic change, the other greenhouse effect gases as the CO2, the CO2 emissions from the energy production, the emission factors of CO2, the sectorial emissions of CO2, the Kyoto protocol and the european market of the CO2 quotas. (A.L.B.)

  18. On rank 4 projective planes

    OpenAIRE

    Bachmann, O.

    1981-01-01

    Let a finite projective plane be called rank m plane if it admits a collineation group G of rank m, let it be called strong rank m plane if moreover GP=G1 for some point-line pair (P,1). It is well known that every rank 2 plane is desarguesian (Theorem of Ostrom and Wagner). It is conjectured that the only rank 3 plane is the plane of order 2. By [1] and [7] the only strong rank 3 plane is the plane of order 2. In this paper it is proved that no strong rank 4 plane exists.

  19. Hybrid single longitudinal mode TEA Co2 laser

    International Nuclear Information System (INIS)

    Laser pulse with high peak power and single longitudinal mode has been obtained from TEA-Co2 by injection a continuous Co2 laser into a TEA-Co2 resonator. Two different methods have been used, hybrid TEA-Co2 laser and injection TEA-Co2 laser. In the first method, the two laser TEA-Co2 and Cw-Co2 are in same resonator, and in the second method, the Cw-Co2 laser is injected into the TEA-Co2 laser resonator using a beam spliter window made of Nacl. A home made Cw-Co2 laser has been used in the present experiment. The tunability of this laser and the relation between the pressure and the current, voltage and output power have been studied. The beam spot size has also been measured. The effect of the gas pressure and that of the output power of Cw-Co2 laser on the single longitudinal mode pulse from the hybrid TEA-Co2 laser. The variation of gas mixture in the TEA-Co2 laser section on the same pulse has also been studied. Concerning the Cw-Co2 laser power and gas mixture of TEA-Co2 laser, typical operating conditions have been obtained for the two systems. 1 tab.; 129 figs.; 82 refs

  20. Improving Ranking Using Quantum Probability

    OpenAIRE

    Melucci, Massimo

    2011-01-01

    The paper shows that ranking information units by quantum probability differs from ranking them by classical probability provided the same data used for parameter estimation. As probability of detection (also known as recall or power) and probability of false alarm (also known as fallout or size) measure the quality of ranking, we point out and show that ranking by quantum probability yields higher probability of detection than ranking by classical probability provided a given probability of ...

  1. Thermodynamic Study of binary an ternary systems containing CO2 + impurities in the context of CO2 transportation

    OpenAIRE

    Coquelet, Christophe; Valtz, Alain; Arpentinier, Philippe

    2014-01-01

    International audience CO2 capture transportation and storage, or CO2 capture transportation and utilization, are two ways which should be considered in the industry in order to reduce the emission of CO2. After capture, CO2 is not pure and contain impurities like SO2, NOx, N2, O2 and Ar for example. Two binary systems involving CO2 were studied in this work (CO2 + SO2 at 263.15 and ACCEPTED MANUSCRIPT 333.21 K and between 0.1 and 8.8 MPa and CO2 + NO in at 232.93, 252.98 and 273.15 K, and...

  2. Inferring high-resolution fossil fuel CO2 records at continental sites from combined 14CO2 and CO observations

    OpenAIRE

    LEVIN Ingeborg; Karstens, Ute

    2011-01-01

    An uncertainty estimate of a purely observational approach to derive hourly regional fossil fuel CO2 offsets (ΔCO2(foss)) at continental CO2 monitoring sites is presented. Weekly mean 14C-based fossil fuel CO2 mixing ratios and corresponding regional CO offsets (ΔCO) are proposed to determine weekly mean ΔCO/ΔCO2(foss) ratios in order to derive hourly ΔCO2(foss) mixing ratios from hourly ΔCO measurements. Respective regional model estimates of CO and CO2(foss) are applied to test this approac...

  3. Method for tracing simulated CO2 leak in terrestrial environment with a 13CO2 tracer

    Science.gov (United States)

    Moni, Christophe; Rasse, Daniel

    2013-04-01

    Facilities for the geological storage of carbon dioxide (CO2) as part of carbon capture and storage (CCS) schemes will be designed to prevent any leakage from the defined 'storage complex'. However, developing regulations and guidance throughout the world (e.g. the EC Directive and the USEPA Vulnerability Evaluation Framework) recognize the importance of assessing the potential for environmental impacts from CO2 storage. RISCS, a European (FP7) project, aims to improve understanding of those impacts that could plausibly occur in the hypothetical case that unexpected leakage occurs. As part of the RISCS project the potential impacts that an unexpected CO2 leaks might have on a cropland ecosystems was investigated. A CO2 exposure field experiment based on CO2 injection at 85 cm depth under an oats culture was designed. To facilitate the characterization of the simulated leaking zone the gas used for injection was produced from natural gas and had a δ13C of -46‰. The aim of the present communication is to depict how the injected gas was traced within the soil-vegetation-atmosphere continuum using 13CO2 continuous cavity ring-down spectrometry (CRDS). Four subsurface experimental injection plots (6m x 3m) were set up. In order to test the effects of different intensity of leakage, the field experiment was designed as to create a longitudinal CO2 gradient for each plot. For this purpose gas supply pipes were inserted at one extremity of each plot at the base of a 45 cm thick layer of sand buried 40 cm below the surface under the clayey plough layer of Norwegian moraine soils. Soil CO2 concentration and isotopic signature were punctually recorded: 1) in the soil at 20 cm depth at 6 positions distributed on the central transect, 2) at the surface following a (50x50 cm) grid sampling pattern, and 3) in the canopy atmosphere at 10, 20, 30 cm along three longitudinal transects (seven sampling point per transect). Soil CO2 fluxes and isotopic signature were finally

  4. Saturated CO2 inhibits microbial processes in CO2-vented deep-sea sediments

    Science.gov (United States)

    de Beer, D.; Haeckel, M.; Neumann, J.; Wegener, G.; Inagaki, F.; Boetius, A.

    2013-08-01

    This study focused on biogeochemical processes and microbial activity in sediments of a natural deep-sea CO2 seepage area (Yonaguni Knoll IV hydrothermal system, Japan). The aim was to assess the influence of the geochemical conditions occurring in highly acidic and CO2 saturated sediments on sulfate reduction (SR) and anaerobic methane oxidation (AOM). Porewater chemistry was investigated from retrieved sediment cores and in situ by microsensor profiling. The sites sampled around a sediment-hosted hydrothermal CO2 vent were very heterogeneous in porewater chemistry, indicating a complex leakage pattern. Near the vents, droplets of liquid CO2 were observed emanating from the sediments, and the pH reached approximately 4.5 in a sediment depth > 6 cm, as determined in situ by microsensors. Methane and sulfate co-occurred in most sediment samples from the vicinity of the vents down to a depth of 3 m. However, SR and AOM were restricted to the upper 7-15 cm below seafloor, although neither temperature, low pH, nor the availability of methane and sulfate could be limiting microbial activity. We argue that the extremely high subsurface concentrations of dissolved CO2 (1000-1700 mM), which disrupt the cellular pH homeostasis, and lead to end-product inhibition. This limits life to the surface sediment horizons above the liquid CO2 phase, where less extreme conditions prevail. Our results may have to be taken into consideration in assessing the consequences of deep-sea CO2 sequestration on benthic element cycling and on the local ecosystem state.

  5. Saturated CO2 inhibits microbial processes in CO2-vented deep-sea sediments

    Directory of Open Access Journals (Sweden)

    A. Boetius

    2013-02-01

    Full Text Available This study focused on biogeochemical processes and microbial activity in sediments of a natural deep-sea CO2 seepage area (Yonaguni Knoll IV hydrothermal system, Japan. The aim was to assess the influence of the geochemical conditions occurring in highly acidic and CO2 saturated sediments on sulphate reduction (SR and anaerobic methane oxidation (AOM. Porewater chemistry was investigated from retrieved sediment cores and in situ by microsensor profiling. The sites sampled around a sediment-hosted hydrothermal CO2 vent were very heterogeneous in porewater chemistry, indicating a complex leakage pattern. Near the vents, droplets of liquid CO2 were observed to emanate from the sediments, and the pH reached approximately 4.5 in a sediment depth >6 cm, as determined in situ by microsensors. Methane and sulphate co-occurred in most sediment samples from the vicinity of the vents down to a depth of at least 3 m. However, SR and AOM were restricted to the upper 7–15 cm below seafloor, although neither temperature, low pH, nor the availability of methane and sulphate could be limiting microbial activity. We argue that the extremely high subsurface concentrations of dissolved CO2 (1000–1700 mM, through the ensuing high H2CO3 levels (approx. 1–2 mM uncouples the proton-motive-force (PMF and thus inhibits biological energy conservation by ATPase-driven phosphorylation. This limits life to the surface sediment horizons above the liquid CO2 phase, where less extreme conditions prevail. Our results may have to be taken into consideration in assessing the consequences of deep-sea CO2 sequestration on benthic element cycling and on the local ecosystem state.

  6. Saturated CO2 inhibits microbial processes in CO2-vented deep-sea sediments

    Directory of Open Access Journals (Sweden)

    D. de Beer

    2013-08-01

    Full Text Available This study focused on biogeochemical processes and microbial activity in sediments of a natural deep-sea CO2 seepage area (Yonaguni Knoll IV hydrothermal system, Japan. The aim was to assess the influence of the geochemical conditions occurring in highly acidic and CO2 saturated sediments on sulfate reduction (SR and anaerobic methane oxidation (AOM. Porewater chemistry was investigated from retrieved sediment cores and in situ by microsensor profiling. The sites sampled around a sediment-hosted hydrothermal CO2 vent were very heterogeneous in porewater chemistry, indicating a complex leakage pattern. Near the vents, droplets of liquid CO2 were observed emanating from the sediments, and the pH reached approximately 4.5 in a sediment depth > 6 cm, as determined in situ by microsensors. Methane and sulfate co-occurred in most sediment samples from the vicinity of the vents down to a depth of 3 m. However, SR and AOM were restricted to the upper 7–15 cm below seafloor, although neither temperature, low pH, nor the availability of methane and sulfate could be limiting microbial activity. We argue that the extremely high subsurface concentrations of dissolved CO2 (1000–1700 mM, which disrupt the cellular pH homeostasis, and lead to end-product inhibition. This limits life to the surface sediment horizons above the liquid CO2 phase, where less extreme conditions prevail. Our results may have to be taken into consideration in assessing the consequences of deep-sea CO2 sequestration on benthic element cycling and on the local ecosystem state.

  7. Diversifying customer review rankings.

    Science.gov (United States)

    Krestel, Ralf; Dokoohaki, Nima

    2015-06-01

    E-commerce Web sites owe much of their popularity to consumer reviews accompanying product descriptions. On-line customers spend hours and hours going through heaps of textual reviews to decide which products to buy. At the same time, each popular product has thousands of user-generated reviews, making it impossible for a buyer to read everything. Current approaches to display reviews to users or recommend an individual review for a product are based on the recency or helpfulness of each review. In this paper, we present a framework to rank product reviews by optimizing the coverage of the ranking with respect to sentiment or aspects, or by summarizing all reviews with the top-K reviews in the ranking. To accomplish this, we make use of the assigned star rating for a product as an indicator for a review's sentiment polarity and compare bag-of-words (language model) with topic models (latent Dirichlet allocation) as a mean to represent aspects. Our evaluation on manually annotated review data from a commercial review Web site demonstrates the effectiveness of our approach, outperforming plain recency ranking by 30% and obtaining best results by combining language and topic model representations. PMID:25795511

  8. 2006 China Retail Ranking

    Institute of Scientific and Technical Information of China (English)

    LEO LIU; JIANG TAO

    2006-01-01

    @@ The rankings of China's leading retailers for fastmoving consumer goods,a collaboration between Beijingbased CTR Market Research and CIB, comes into its third term. According to our findings,with the competitive advantages such as better shopping environments and cheaper prices,the large-scale retailers, or hypermarkets, are continuing to increase their market shares.

  9. OutRank

    DEFF Research Database (Denmark)

    Müller, Emmanuel; Assent, Ira; Steinhausen, Uwe; Seidl, Thomas

    Outlier detection is an important data mining task for consistency checks, fraud detection, etc. Binary decision making on whether or not an object is an outlier is not appropriate in many applications and moreover hard to parametrize. Thus, recently, methods for outlier ranking have been proposed...

  10. Ratings and Rankings

    OpenAIRE

    Budin, Wendy C.

    2010-01-01

    In this column, the editor of The Journal of Perinatal Education describes ranking systems for scholarly journals. The editor also describes the contents of this issue, which offer a broad range of resources, research, and inspiration for childbirth educators in their efforts to promote natural, safe, and healthy birth.

  11. Quantitative analysis of an engineered CO2-fixing Escherichia coli reveals great potential of heterotrophic CO2 fixation

    OpenAIRE

    Gong, Fuyu; Liu, Guoxia; Zhai, Xiaoyun; Zhou, Jie; Cai, Zhen; Yin LI

    2015-01-01

    Background Production of fuels from the abundant and wasteful CO2 is a promising approach to reduce carbon emission and consumption of fossil fuels. Autotrophic microbes naturally assimilate CO2 using energy from light, hydrogen, and/or sulfur. However, their slow growth rates call for investigation of the possibility of heterotrophic CO2 fixation. Although preliminary research has suggested that CO2 fixation in heterotrophic microbes is feasible after incorporation of a CO2-fixing bypass int...

  12. Anthropogenic CO2 emissions in Africa

    Directory of Open Access Journals (Sweden)

    R. A. Houghton

    2008-11-01

    Full Text Available An understanding of the regional contributions and trends of anthropogenic carbon dioxide (CO2 emissions is critical to design mitigation strategies aimed at stabilizing atmospheric greenhouse gases. Here we report CO2 emissions from the combustion of fossil fuels and land use change in Africa for various time periods. Africa was responsible for an average of 500 TgC y−1 for the period 2000–2005. These emissions resulted from the combustion of fossil fuels (260 TgC y−1 and land use change (240 TgC y−1. Over this period, the African share of global emissions from land use change was 17%. For 2005, the last year reported in this study, African fossil fuel emissions were 285 TgC accounting for 3.7% of the global emissions. The 2000–2005 growth rate in African fossil fuel emissions was 3.2% y−1, very close to the global average. Fossil fuel emissions per capita in Africa are among the lowest in the world, at 0.32 tC y−1 compared to the global average of 1.2 tC y−1. The average amount of carbon (C emitted as CO2 to produce 1 US $ of Gross Domestic Product (GDP in Africa in 2005 was 187 gC/$, close to the world average of 199 gC/$. With the fastest population growth in the world and rising per capita GDP, Africa is likely to increase its share of global emissions over the coming decades although emissions from Africa will remain low compared to other continents.

  13. PLAINS CO2 REDUCTION (PCOR) PARTNERSHIP

    Energy Technology Data Exchange (ETDEWEB)

    Edward N. Steadman; Daniel J. Daly; Lynette L. de Silva; John A. Harju; Melanie D. Jensen; Erin M. O' Leary; Wesley D. Peck; Steven A. Smith; James A. Sorensen

    2006-01-01

    During the period of October 1, 2003, through September 30, 2005, the Plains CO2 Reduction (PCOR) Partnership, identified geologic and terrestrial candidates for near-term practical and environmentally sound carbon dioxide (CO2) sequestration demonstrations in the heartland of North America. The PCOR Partnership region covered nine states and three Canadian provinces. The validation test candidates were further vetted to ensure that they represented projects with (1) commercial potential and (2) a mix that would support future projects both dependent and independent of CO2 monetization. This report uses the findings contained in the PCOR Partnership's two dozen topical reports and half-dozen fact sheets as well as the capabilities of its geographic information system-based Decision Support System to provide a concise picture of the sequestration potential for both terrestrial and geologic sequestration in the PCOR Partnership region based on assessments of sources, sinks, regulations, deployment issues, transportation, and capture and separation. The report also includes concise action plans for deployment and public education and outreach as well as a brief overview of the structure, development, and capabilities of the PCOR Partnership. The PCOR Partnership is one of seven regional partnerships under Phase I of the U.S. Department of Energy National Energy Technology Laboratory's Regional Carbon Sequestration Partnership program. The PCOR Partnership, comprising 49 public and private sector members, is led by the Energy & Environmental Research Center at the University of North Dakota. The international PCOR Partnership region includes the Canadian provinces of Alberta, Saskatchewan, and Manitoba and the states of Montana (part), Wyoming (part), North Dakota, South Dakota, Nebraska, Missouri, Iowa, Minnesota, and Wisconsin.

  14. Plasma Arc Augmented CO2 laser welding

    DEFF Research Database (Denmark)

    Bagger, Claus; Andersen, Mikkel; Frederiksen, Niels;

    2001-01-01

    In order to reduce the hardness of laser beam welded 2.13 mm medium strength steel CMn 250, a plasma arc has been used simultaneously with a 2.6 kW CO2 laser source. In a number of systematic laboratory tests, the plasma arc current, plasma gas flow and distance to the laser source were varied with....... With the addition of a plasma arc, the hardness could overall be reduced to between 200 and 220 HV1, i.e. about 27 percent. In the seam middle, the reduction was 36 percent....

  15. Progress on CO2 laser gas fusion

    International Nuclear Information System (INIS)

    Experimental and theoretical investigations have been carried out on the interaction of CO2-laser radiation with underdense plasma (1017-5x1018 cm3) in strong magnetic fields with the aim of determining feasibility of this approach to CTR. The efforts of three groups, University of Washington - Mathematical Sciences, MIT - Avco, and Princeton are reported. The experiments show that the theoretically predicted self-focusing of the beam in the plasma is effective. Shock waves and bleaching waves have been observed. Theoretical calculations of thermonuclear yields show that large gains are possible from this type of reactor. (author)

  16. Superconductivity in CeCo2 nanoparticles

    International Nuclear Information System (INIS)

    Both Ce and Co are essentially nonmagnetic in Pauli-paramagnetic CeCo2, which undergoes a superconducting transition near 1K. When made into 58-A nanoparticles, the compound becomes paramagnetic. Meanwhile, based on heat capacity measurements, the nanoparticles remain to be nonsuperconducting down to 0.4K but exhibit a low-temperature Kondo anomaly with C/T∼ 350mJ/molK2 at 0.4K. Such intriguing effects are consequences of the competition between superconducting gap and electronic spectrum's mean level spacing

  17. Entornos Agroambientales: Almacenes Naturales De Co2.

    OpenAIRE

    Juan Isidro Sánchez Leyva; Danay Sánchez Méndez; Juan Manuel Sánchez Castro; Carlos Wise Thomas; Ana Ida Vilier Cintra; Maylín Sánchez Castro

    2005-01-01

    Cultivos únicos eternos y la extinción de especies; contaminaciones atmosféricas, edáficas e hídricas; la ampliación del agujero de la capa de Ozono, etc. unido al mal uso de la tierra contribuyen al empobrecimiento de comunidades y naciones. Se evaluaron sistemas de cultivos múltiples como sumideros naturales o bancos de CO2. Y se intercalaron leguminosas por sus conocidos y probados beneficios y otras especies anuales en árboles y arbustos conducidos desde 1988-90 en el macizo montañoso Sag...

  18. Chilled ammonia process for CO2 capture

    DEFF Research Database (Denmark)

    Darde, Victor Camille Alfred; Thomsen, Kaj; van Well, Willy J. M;

    2009-01-01

    The chilled ammonia process absorbs the CO2 at low temperature (2-10 degrees C). The heat of absorption of carbon dioxide by ammonia is significantly lower than for amines. In addition, degradation problems can be avoided and a high carbon dioxide capacity is achieved. Hence, this process shows...... C and pressure up to 100 bars [1]. The results show that solid phases consisting of ammonium carbonate and bicarbonate are formed in the absorber. The energy requirements in the absorber and in the desorber have been studied. The enthalpy calculations show that an energy requirement for the desorber...

  19. Childhood asthma and anthropogenic CO2 emissions

    OpenAIRE

    Dosanjh A

    2011-01-01

    Amrita DosanjhPediatric Pulmonologist, San Diego, California, USATrends in the incidence of childhood asthma worldwide have paralleled the sharp increase in carbon dioxide (CO2) emissions, over at least the last two decades. The prevalence of asthma in the United States has quadrupled over the last 20 years in part due to climate-related factors. In a report released by Harvard Medical School and the Center for Health and the Global Environment, it was noted that there was an increase in asth...

  20. CO2-Speicherung. Chancen und Risiken

    OpenAIRE

    Michael Kühn

    2011-01-01

    Der Mensch greift durch seine Kohlendioxid-Emissionen wesentlich in den Kohlenstoffkreislauf der Erde ein. Im Rahmen der Klimapolitik wird daher die Lagerung von Kohlendioxid in tiefe Gesteinsschichten erwogen, mit einem noch zu bestätigenden Potenzial von 25 % an der vorgesehenen Gesamtreduktion. Die für Deutschland bzw. die weltweit abgeschätzten Speicherkapazitäten könnten für einige Jahrzehnte ausreichend sein. Die Quellen, an denen CO2 abgetrennt werden kann, finden sich in der Großindus...

  1. The Influence of CO2 Solubility in Brine on Simulation of CO2 Injection into Water Flooded Reservoir and CO2 WAG

    DEFF Research Database (Denmark)

    Yan, Wei; Stenby, Erling Halfdan

    2010-01-01

    reservoirs and in many situations alternating injection of water and CO2 is required to stabilize the injection front. Both scenarios involve a large amount of water, making CO2 solubility in brine, which is around ten times higher than methane solubility, a non-negligible factor in the relevant reservoir......Injection of CO2 into depleted oil reservoirs is not only a traditional way to enhance oil recovery but also a relatively cheaper way to sequester CO2 underground since the increased oil production can offset some sequestration cost. CO2 injection process is often applied to water flooded...... simulations. In our previous study, a 1-D slimtube simulator, which rigorously accounts for both CO2 solubility in brine and water content in hydrocarbon phases using the Peng-Robinson EoS modified by Soreide and Whitson, has been used to investigate the influence of CO2 solubility on the simulation of...

  2. The Influence of CO2 Solubility in Brine on Simulation of CO2 Injection into Water Flooded Reservoir and CO2 WAG

    DEFF Research Database (Denmark)

    Yan, Wei; Stenby, Erling Halfdan

    2010-01-01

    factors, including temperature, pressure, salinity, water injection pore volume, WAG ratio and CO2 slug size, on the simulation results was also discussed. In addition, the results for CO2 injection into water flooded reservoirs were also compared with those from the previous study.......Injection of CO2 into depleted oil reservoirs is not only a traditional way to enhance oil recovery but also a relatively cheaper way to sequester CO2 underground since the increased oil production can offset some sequestration cost. CO2 injection process is often applied to water flooded...... reservoirs and in many situations alternating injection of water and CO2 is required to stabilize the injection front. Both scenarios involve a large amount of water, making CO2 solubility in brine, which is around ten times higher than methane solubility, a non-negligible factor in the relevant reservoir...

  3. CO2 Emissions from Fuel Combustion 2011: Highlights

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2011-07-01

    How much CO2 are countries emitting? Where is it coming from? In the lead-up to the UN climate negotiations in Durban, the latest information on the level and growth of CO2 emissions, their source and geographic distribution will be essential to lay the foundation for a global agreement. To provide input to and support for the UN process the IEA is making available for free download the 'Highlights' version of CO2 Emissions from Fuel Combustion. This annual publication contains: - estimates of CO2 emissions by country from 1971 to 2009; - selected indicators such as CO2/GDP, CO2/capita, CO2/TPES and CO2/kWh; - CO2 emissions from international marine and aviation bunkers, and other relevant information. These estimates have been calculated using the IEA energy databases and the default methods and emission factors from the Revised 1996 IPCC Guidelines for National Greenhouse Gas Inventories.

  4. CO2 Emissions from Fuel Combustion - 2012 Highlights

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2012-07-01

    How much CO2 are countries emitting? Where is it coming from? In the lead-up to the UN climate negotiations in Doha, the latest information on the level and growth of CO2 emissions, their source and geographic distribution will be essential to lay the foundation for a global agreement. To provide input to and support for the UN process the IEA is making available for free download the 'Highlights' version of CO2 Emissions from Fuel Combustion. This annual publication contains: estimates of CO2 emissions by country from 1971 to 2010; selected indicators such as CO2/GDP, CO2/capita, CO2/TPES and CO2/kWh; and CO2 emissions from international marine and aviation bunkers, and other relevant information.

  5. Response of atmospheric CO2 to changes in land use

    International Nuclear Information System (INIS)

    This chapter examines how different histories of CO2 release from past changes in land use influence the simulation of past and future changes in atmospheric CO2. The authors first simulate past change in atmospheric CO2 using reconstructed histories of land-use CO2 release from a historical-ecological model of land-use change and CO2 release. They examine the impact of each history on the coincidence between simulated and observed atmospheric CO2. They then compare these CO2 release histories, and their contribution to coincidence or noncoincidence of simulation and observation, with histories reconstructed by deconvolution of the atmospheric CO2 record. They conclude by exploring the implications of these deconvolved reconstructions for the simulation of future changes in atmospheric CO2

  6. On Leakage from Geologic Storage Reservoirs of CO2

    Energy Technology Data Exchange (ETDEWEB)

    Pruess, Karsten

    2006-02-14

    Large amounts of CO2 would need to be injected underground to achieve a significant reduction of atmospheric emissions. The large areal extent expected for CO2 plumes makes it likely that caprock imperfections will be encountered, such as fault zones or fractures, which may allow some CO2 to escape from the primary storage reservoir. Leakage of CO2 could also occur along wellbores. Concerns with escape of CO2 from a primary geologic storage reservoir include (1) acidification of groundwater resources, (2) asphyxiation hazard when leaking CO2 is discharged at the land surface, (3) increase in atmospheric concentrations of CO2, and (4) damage from a high-energy, eruptive discharge (if such discharge is physically possible). In order to gain public acceptance for geologic storage as a viable technology for reducing atmospheric emissions of CO2, it is necessary to address these issues and demonstrate that CO2 can be injected and stored safely in geologic formations.

  7. CO 2-water-basalt interaction. Numerical simulation of low temperature CO 2 sequestration into basalts

    Science.gov (United States)

    Gysi, Alexander P.; Stefánsson, Andri

    2011-09-01

    The interaction between CO 2-rich waters and basaltic glass was studied using reaction path modeling in order to get insight into the water-rock reaction process including secondary mineral composition, water chemistry and mass transfer as a function of CO 2 concentration and reaction progress ( ξ). The calculations were carried out at 25-90 °C and pCO 2 to 30 bars and the results were compared to recent experimental observations and natural systems. A thermodynamic dataset was compiled from 25 to 300 °C in order to simulate mineral saturations relevant to basalt alteration in CO 2-rich environment including revised key aqueous species for mineral dissolution reactions and apparent Gibbs energies for clay and carbonate solid solutions observed to form in nature. The dissolution of basaltic glass in CO 2-rich waters was found to be incongruent with the overall water composition and secondary mineral formation depending on reaction progress and pH. Under mildly acid conditions in CO 2 enriched waters (pH carbonates predominated. Iron, Al and Si were immobile whereas the Mg and Ca mobility depended on the mass of carbonate formed and water pH. Upon quantitative CO 2 mineralization, the pH increased to >8 resulting in Ca-Mg-Fe smectite, zeolites and calcite formation, reducing the mobility of most dissolved elements. The dominant factor determining the reaction path of basalt alteration and the associated element mobility was the pH of the water. In turn, the pH value was determined by the concentration of CO 2 and extent of reaction. The composition of the carbonates depended on the mobility of Ca, Mg and Fe. At pH carbonates with the incorporation of Ca and Mg. At pH >8, the mobility of Fe and Mg was limited due to the formation of clays whereas Ca was incorporated into calcite, zeolites and clays. Competing reactions between clays (Ca-Fe smectites) and carbonates at low pH, and zeolites and clays (Mg-Fe smectites) and carbonates at high pH, controlled the

  8. Stable isotope measurements of atmospheric CO2

    International Nuclear Information System (INIS)

    The measurement of stable carbon isotope ratios of atmospheric carbon dioxide, δ13CO2 are useful for partitioning surface-atmospheric fluxes into terrestrial and oceanic components. δC18OO also has potential for segregating photosynthetic and respiratory fluxes in terrestrial ecosystems. Here we describe in detail the techniques for making these measurements. The primary challenge for all of the techniques used to measure isotopes of atmospheric CO2 is to achieve acceptable accuracy and precision and to maintain them over the decades needed to observe carbon cycle variability. The keys to success such an approach are diligent intercalibrations of laboratories from around the world, as well as the use of multiple techniques such as dual inlet and GC-IRMS and the intercomparison of such measurements. We focus here on two laboratories, the Stable Isotope Lab at the Institute for Arctic and Alpine Research (INSTAAR) at the University of Colorado is described and the Commonwealth Scientific and Industrial Research Organisation - Atmospheric Research (CSIRO). Different approaches exist at other laboratories (e.g. programs operated by Scripps Institution of Oceanography (SIO) and The Center for Atmospheric and Oceanic Studies, Toboku University (TU)) however these are not discussed here. Finally, we also discuss the recently developed Gas Chromatography - Isotope Ratio Mass Spectrometry (GC-IRMS) technique which holds significant promise for measuring ultra-small samples of gas with good precision. (author)

  9. Gas power with minimized CO2 emission

    International Nuclear Information System (INIS)

    Gas power is currently much debated in Norway. The article answers some of the questions asked in this debate. The assertion that conventional gas power is obsolete technology is refuted. For instance, gas turbines are high-tech in every respect. The technological goals at present are reduced cost per kW, reduced life-cycle cost, increased efficiency, reduced emission of NOx, increased reliability and accessibility and shorter construction period. There is at present and in the near future no market for CO2-free gas power technology; hence there is very little technological development in this direction. However, the US Department of Energy is now beginning to increase financial support for research projects in this field. It is pointed out that such a programme faces great challenges and requires a real commitment involving high economic risk. The article suggests a realistic time perspective of at least ten years for the development of commercially acceptable CO2-free gas power technology and proposes some research areas

  10. Public Acceptance for Geological CO2-Storage

    Science.gov (United States)

    Schilling, F.; Ossing, F.; Würdemann, H.; Co2SINK Team

    2009-04-01

    Public acceptance is one of the fundamental prerequisites for geological CO2 storage. In highly populated areas like central Europe, especially in the vicinity of metropolitan areas like Berlin, underground operations are in the focus of the people living next to the site, the media, and politics. To gain acceptance, all these groups - the people in the neighbourhood, journalists, and authorities - need to be confident of the security of the planned storage operation as well as the long term security of storage. A very important point is to show that the technical risks of CO2 storage can be managed with the help of a proper short and long term monitoring concept, as well as appropriate mitigation technologies e.g adequate abandonment procedures for leaking wells. To better explain the possible risks examples for leakage scenarios help the public to assess and to accept the technical risks of CO2 storage. At Ketzin we tried the following approach that can be summed up on the basis: Always tell the truth! This might be self-evident but it has to be stressed that credibility is of vital importance. Suspiciousness and distrust are best friends of fear. Undefined fear seems to be the major risk in public acceptance of geological CO2-storage. Misinformation and missing communication further enhance the denial of geological CO2 storage. When we started to plan and establish the Ketzin storage site, we ensured a forward directed communication. Offensive information activities, an information centre on site, active media politics and open information about the activities taking place are basics. Some of the measures were: - information of the competent authorities through meetings (mayor, governmental authorities) - information of the local public, e.g. hearings (while also inviting local, regional and nation wide media) - we always treated the local people and press first! - organizing of bigger events to inform the public on site, e.g. start of drilling activities (open

  11. Mathematical modeling of hybrid CO2 laser

    International Nuclear Information System (INIS)

    A Teller-landau six-temperature model describing the dynamic emission of single mode TEA CO2 laser has been adapted. This model has been also used to describe the mechanism of obtaining relatively high-power output pulses from hybrid TE-TEA or CW-TEA CO2 laser consisting of high and low-pressure sections. The suggested mathematical model allows to investigate the mechanism which limits the TEA oscillation to single longitudinal mode (SLM) due to the narrow gain bandwidth of low-pressure section, and also to study the effect of the laser input parameters on the smooth output laser pulse parameters. In addition, numerical solutions, of non-linear rate equation system of suggested model are quantitatively discussed. The solutions describe the radiation field intensity, the population inversion, and the energy transfer processes. The calculated values of maximum peak power, total energy in pulse, pulse width, etc. are in a very good agreement with the observed experimental values. (author)

  12. Uncertainty in gridded CO2 emissions estimates

    Science.gov (United States)

    Hogue, Susannah; Marland, Eric; Andres, Robert J.; Marland, Gregg; Woodard, Dawn

    2016-05-01

    We are interested in the spatial distribution of fossil-fuel-related emissions of CO2 for both geochemical and geopolitical reasons, but it is important to understand the uncertainty that exists in spatially explicit emissions estimates. Working from one of the widely used gridded data sets of CO2 emissions, we examine the elements of uncertainty, focusing on gridded data for the United States at the scale of 1° latitude by 1° longitude. Uncertainty is introduced in the magnitude of total United States emissions, the magnitude and location of large point sources, the magnitude and distribution of non-point sources, and from the use of proxy data to characterize emissions. For the United States, we develop estimates of the contribution of each component of uncertainty. At 1° resolution, in most grid cells, the largest contribution to uncertainty comes from how well the distribution of the proxy (in this case population density) represents the distribution of emissions. In other grid cells, the magnitude and location of large point sources make the major contribution to uncertainty. Uncertainty in population density can be important where a large gradient in population density occurs near a grid cell boundary. Uncertainty is strongly scale-dependent with uncertainty increasing as grid size decreases. Uncertainty for our data set with 1° grid cells for the United States is typically on the order of ±150%, but this is perhaps not excessive in a data set where emissions per grid cell vary over 8 orders of magnitude.

  13. Covalent Triazine-Based Frameworks with Ultramicropores and High Nitrogen Contents for Highly Selective CO2 Capture.

    Science.gov (United States)

    Wang, Keke; Huang, Hongliang; Liu, Dahuan; Wang, Chang; Li, Jinping; Zhong, Chongli

    2016-05-01

    Porous organic frameworks (POFs) are a class of porous materials composed of organic precursors linked by covalent bonds. The objective of this work is to develop POFs with both ultramicropores and high nitrogen contents for CO2 capture. Specifically, two covalent triazine-based frameworks (CTFs) with ultramicropores (pores of width <7 Å) based on short (fumaronitrile, FUM) and wide monomers (1,4-dicyanonaphthalene, DCN) were synthesized. The obtained CTF-FUM and CTF-DCN possess excellent chemical and thermal stability with ultramicropores of 5.2 and 5.4 Å, respectively. In addition, they exhibit excellent ability to selectively capture CO2 due to ultramicroporous nature. Especially, CTF-FUM-350 has the highest nitrogen content (27.64%) and thus the highest CO2 adsorption capacity (57.2 cc/g at 298 K) and selectivities for CO2 over N2 and CH4 (102.4 and 20.5 at 298 K, respectively) among all CTF-FUM and CTF-DCN. More impressively, as far as we know, the CO2/CH4 selectivity is larger than that of all reported CTFs and ranks in top 10 among all reported POFs. Dynamic breakthrough curves indicate that both CTFs could indeed separate gas mixtures of CO2/N2 and CO2/CH4 completely. PMID:27081869

  14. Quantifying CO2 abatement costs in the power sector

    OpenAIRE

    Van den Bergh, Kenneth; Delarue, Erik

    2015-01-01

    CO2 cap-and-trade mechanisms and CO2 emission taxes are becoming increasingly widespread. To assess the impact of a CO2 price, marginal abatement cost curves (MACCs) are a commonly used tool by policy makers, providing a direct graphical link between a CO2 price and the expected abatement. However, such MACCs can suffer from issues related to robustness and granularity. This paper focuses on the relation between a CO2 emission cost and CO2 emission reductions in the power sector. The authors ...

  15. Estimation of continuous anthropogenic CO2: model-based evaluation of CO2, CO, δ13C(CO2) and Δ14C(CO2) tracer methods

    Science.gov (United States)

    Vardag, S. N.; Gerbig, C.; Janssens-Maenhout, G.; Levin, I.

    2015-11-01

    We investigate different methods for estimating anthropogenic CO2 using modeled continuous atmospheric concentrations of CO2 alone, as well as CO2 in combination with the surrogate tracers CO, δ13C(CO2) and Δ14C(CO2). These methods are applied at three hypothetical stations representing rural, urban and polluted conditions. We find that, independent of the tracer used, an observation-based estimate of continuous anthropogenic CO2 is not yet feasible at rural measurement sites due to the low signal-to-noise ratio of anthropogenic CO2 estimates at such settings. The tracers δ13C(CO2) and CO provide an accurate possibility to determine anthropogenic CO2 continuously, only if all CO2 sources in the catchment area are well characterized or calibrated with respect to their isotopic signature and CO to anthropogenic CO2 ratio. We test different calibration strategies for the mean isotopic signature and CO to CO2 ratio using precise Δ14C(CO2) measurements on monthly integrated as well as on grab samples. For δ13C(CO2), a calibration with annually averaged 14C(CO2) grab samples is most promising, since integrated sampling introduces large biases into anthropogenic CO2 estimates. For CO, these biases are smaller. The precision of continuous anthropogenic CO2 determination using δ13C(CO2) depends on measurement precision of δ13C(CO2) and CO2, while the CO method is mainly limited by the variation in natural CO sources and sinks. At present, continuous anthropogenic CO2 could be determined using the tracers δ13C(CO2) and/or CO with a precision of about 30 %, a mean bias of about 10 % and without significant diurnal discrepancies. Hypothetical future measurements of continuous Δ14C(CO2) with a precision of 5 ‰ are promising for anthropogenic CO2 determination (precision ca. 10-20 %) but are not yet available. The investigated tracer-based approaches open the door to improving, validating and reducing biases of highly resolved emission inventories using atmospheric

  16. Factors affecting the direct mineralization of CO2 with olivine

    Institute of Scientific and Technical Information of China (English)

    Soonchul Kwon; Maohong Fan; Herbert F. M. DaCosta; Armistead G. Russell

    2011-01-01

    Olivine,one of the most abundant minerals existing in nature,is explored as a CO2 carbonation agent for direct carbonation of CO2 in flue gas.Olivine based CO2 capture is thermodynamically favorable and can form a stable carbonate for long-term storage.Experimental results have shown that water vapor plays an important role in improving CO2 carbonation rate and capacities.Other operation conditions including reaction temperature,initial CO2 concentration,residence time corresponding to the flow rate of CO2 gas stream,and water vapor concentration also considerably affect the performance of the technology.

  17. Accelerated Carbonation of Steel Slags Using CO2 Diluted Sources: CO2 Uptakes and Energy Requirements

    OpenAIRE

    Baciocchi, Renato; Costa, Giulia; Polettini, Alessandra; Pomi, Raffaella; Stramazzo, Alessio; Zingaretti, Daniela

    2016-01-01

    This work presents the results of carbonation experiments performed on Basic Oxygen Furnace (BOF) steel slag samples employing gas mixtures containing 40 and 10% CO2 vol. simulating the gaseous effluents of gasification and combustion processes respectively, as well as 100% CO2 for comparison purposes. Two routes were tested, the slurry-phase (L/S = 5 l/kg, T = 100°C and Ptot = 10 bar) and the thin-film (L/S = 0.3–0.4 l kg, T = 50°C and Ptot = 7–10 bar) routes. For each one, the CO2 uptake ac...

  18. CO2 capture processes in power plants - Le captage du CO2 dans les centrales thermiques

    CERN Document Server

    Bouallou, Chakib

    2010-01-01

    This review is devoted to assess and compare various processes aiming at recover CO2 from power plants fed with natural gas (NGCC) and pulverized coal (PC). These processes are post combustion CO2 capture using chemical solvents, natural gas reforming for pre-combustion capture and oxy-fuel combustion with cryogenic recovery of CO2. These processes were evaluated to give some clues for choosing the best option for each type of power plant. The comparison of these various concepts suggests that, in the short and medium term, chemical absorption is the most interesting process for NGCC power plants. For CP power plants, oxy-combustion can be a very interesting option, as well as post-combustion capture by chemical solvents.

  19. Reducing CO2 from shipping – do non-CO2 effects matter?

    Directory of Open Access Journals (Sweden)

    M. S. Eide

    2013-04-01

    Full Text Available Shipping is a growing sector in the global economy, and it contributions to global CO2 emissions are expected to increase. CO2 emissions from the world shipping fleet will likely be regulated in the near future, and studies have shown that significant emission reductions can be achieved at low cost. Regulations are being discussed for both existing ships as well as for future additions to the fleet. In this study a plausible CO2 emission reduction inventory is constructed for the cargo fleet existing in 2010, as well as for container ships, bulk ships and tankers separately. In the reduction inventories, CO2 emissions are reduced by 25–32% relative to baseline by applying 15 technical and operational emission reduction measures in accordance with a ship-type-specific cost-effectiveness criterion, and 9 other emission compounds are changed as a technical implication of reducing CO2. The overall climate and environmental effects of the changes to all 10 emission components in the reduction inventory are assessed using a chemical transport model, radiative forcing (RF models and a simple climate model. We find substantial environmental and health benefits with up to 5% reduction in surface ozone levels, 15% reductions in surface sulfate and 10% reductions in wet deposition of sulfate in certain regions exposed to heavy ship traffic. The major ship types show distinctly different contributions in specific locations. For instance, the container fleet contributes 50% of the sulfate decline on the west coast of North America. The global radiative forcing from a 1 yr emission equal to the difference between baseline and reduction inventory shows an initial strong positive forcing from non-CO2 compounds. This warming effect is due to reduced cooling by aerosols and methane. After approximately 25 yr, the non-CO2 forcing is balanced by the CO2 forcing. For the global mean temperature change, we find a shift from warming to cooling after approximately 60

  20. CO2 point sources and subsurface storage capacities for CO2 in aquifers in Norway

    International Nuclear Information System (INIS)

    The GESTCO project comprises a study of the distribution and coincidence of thermal CO2 emission sources and location/quality of geological storage capacity in Europe. Four of the most promising types of geological storage are being studied. 1. Onshore/offshore saline aquifers with or without lateral seal. 2. Low entalpy geothermal reservoirs. 3. Deep methane-bearing coal beds and abandoned coal and salt mines. 4. Exhausted or near exhausted hydrocarbon structures. In this report we present an inventory of CO2 point sources in Norway (1999) and the results of the work within Study Area C: Deep saline aquifers offshore/near shore Northern and Central Norway. Also offshore/near shore Southern Norway has been included while the Barents Sea is not described in any detail. The most detailed studies are on the Tilje and Aare Formations on the Troendelag Platform off Mid-Norway and on the Sognefjord, Fensfjord and Krossfjord Formations, southeast of the Troll Field off Western Norway. The Tilje Formation has been chosen as one of the cases to be studied in greater detail (numerical modelling) in the project. This report shows that offshore Norway, there are concentrations of large CO2 point sources in the Haltenbanken, the Viking Graben/Tampen Spur area, the Southern Viking Graben and the central Trough, while onshore Norway there are concentrations of point sources in the Oslofjord/Porsgrund area, along the coast of western Norway and in the Troendelag. A number of aquifers with large theoretical CO2 storage potential are pointed out in the North Sea, the Norwegian Sea and in the Southern Barents Sea. The storage capacity in the depth interval 0.8 - 4 km below sea level is estimated to be ca. 13 Gt (13000000000 tonnes) CO2 in geological traps (outside hydrocarbon fields), while the storage capacity in aquifers not confined to traps is estimated to be at least 280 Gt CO2. (Author)

  1. Supercritical CO2 as a substitute of volatile hydrocarbons; Superkritisch CO2 vervangt vluchtige koolwaterstoffen

    Energy Technology Data Exchange (ETDEWEB)

    Folkerts, G. (ed.)

    2006-05-15

    In many cases supercritical carbon dioxide can replace volatile hydrocarbons in extraction processes. Currently gaseous or liquid CO2 is already used for industrial purification processes, extraction of caffeine from coffee and as a solvent for paint. Although supercritical extraction s a batch process the technique can be applied as a continuous process. [Dutch] In processen waar vluchtige koolwaterstoffen worden ingezet om stoffen te extraheren, biedt superkritisch CO2 een milieuvriendelijk alternatief. Het koolzuur dat zowel in de vloeistof- als gasfase zit, wordt dan ook steeds meer ingezet in extractieprocessen.

  2. Low rank Multivariate regression

    CERN Document Server

    Giraud, Christophe

    2010-01-01

    We consider in this paper the multivariate regression problem, when the target regression matrix $A$ is close to a low rank matrix. Our primary interest in on the practical case where the variance of the noise is unknown. Our main contribution is to propose in this setting a criterion to select among a family of low rank estimators and prove a non-asymptotic oracle inequality for the resulting estimator. We also investigate the easier case where the variance of the noise is known and outline that the penalties appearing in our criterions are minimal (in some sense). These penalties involve the expected value of the Ky-Fan quasi-norm of some random matrices. These quantities can be evaluated easily in practice and upper-bounds can be derived from recent results in random matrix theory.

  3. Fractional cointegration rank estimation

    DEFF Research Database (Denmark)

    Lasak, Katarzyna; Velasco, Carlos

    We consider cointegration rank estimation for a p-dimensional Fractional Vector Error Correction Model. We propose a new two-step procedure which allows testing for further long-run equilibrium relations with possibly different persistence levels. The fi…rst step consists in estimating the...... parameters of the model under the null hypothesis of the cointegration rank r = 1, 2, ..., p-1. This step provides consistent estimates of the cointegration degree, the cointegration vectors, the speed of adjustment to the equilibrium parameters and the common trends. In the second step we carry out a sup......-likelihood ratio test of no-cointegration on the estimated p - r common trends that are not cointegrated under the null. The cointegration degree is re-estimated in the second step to allow for new cointegration relationships with different memory. We augment the error correction model in the second step to...

  4. Multiplex PageRank

    CERN Document Server

    Halu, Arda; Pansaraza, Pietro; Bianconi, Ginestra

    2013-01-01

    Many complex systems can be described as multiplex networks in which the same nodes can interact with one another in different layers, thus forming a set of interacting and co-evolving networks. Examples of such multiplex systems are social networks where people are involved in different types of relationships and interact through various forms of communication media. The ranking of nodes in multiplex networks is one of the most pressing and challenging tasks that research on complex networks is currently facing. When pairs of nodes can be connected through multiple links and in multiple layers, the ranking of nodes should necessarily reflect the importance of nodes in one layer as well as their importance in other interdependent layers. In this paper, we draw on the idea of biased random walks to define the Multiplex PageRank centrality measure in which the effects of the interplay between networks on the centrality of nodes are directly taken into account. In particular, depending on the intensity of the in...

  5. Emission evaluation of CO 2 and CH4 gases in the selected gas pressure booster station in the Bangestan field of the National Iranian Oil Company

    OpenAIRE

    Mehdi Ahmadi; Maedeh Rozkhosh; Nemat-allah Jaafarzadeh Haghighifard

    2014-01-01

    Background: Iran is located in the seventh rank in terms of CO2 emissions resulting from the fuel combustion in the world. Gas compressor booster stations, due to the several sources of contaminants, are causing the release of large amounts of CO2 and CH4, which will cause climate change; therefore, estimating the emissions of the gases from oil and gas, different processing units are necessary. Methods: In this study, the emissions factor method, provided by various organizations, was used f...

  6. Novel Long-Term CO2 Removal System Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Current Technology for CO2 removal from enclosed air of spacecraft utilizes LiOH canisters for CO2 absorption. This absorption is irreversible so longer flights...

  7. Mapping palm oil expansion using SAR to study the impact on the CO2 cycle

    International Nuclear Information System (INIS)

    With Malaysia being the second largest palm oil producer in the world and the fact that palm oil ranks first in vegetable oil production on the world market the palm oil industry became an important factor in the country. Along with the expansion of palm oil across the nation causing deforestation of natural rain forest and conversion of peat land into plantation land there are several factors causing a tremendous increase in carbon dioxide (CO2) emissions. Main causes of CO2 emission apart from deforestation and peat-land conversion are the fires to create plantation land plus the fires burning waste products of the plantations itself. This paper describes a project that aims at the development of a remote sensing monitoring system to allow a continuous observation of oil palm plantation activities and expansion in order to be able to quantify CO2 emissions. The research concentrates on developing a spaceborne synthetic aperture radar information extraction system for palm oil plantations in the Tropics. This will lead to objective figures that can be used internationally to create a policy implementation plan to sustainably reduce CO2 emission in the future

  8. Mapping palm oil expansion using SAR to study the impact on the CO2 cycle

    Science.gov (United States)

    Pohl, Christine

    2014-06-01

    With Malaysia being the second largest palm oil producer in the world and the fact that palm oil ranks first in vegetable oil production on the world market the palm oil industry became an important factor in the country. Along with the expansion of palm oil across the nation causing deforestation of natural rain forest and conversion of peat land into plantation land there are several factors causing a tremendous increase in carbon dioxide (CO2) emissions. Main causes of CO2 emission apart from deforestation and peat-land conversion are the fires to create plantation land plus the fires burning waste products of the plantations itself. This paper describes a project that aims at the development of a remote sensing monitoring system to allow a continuous observation of oil palm plantation activities and expansion in order to be able to quantify CO2 emissions. The research concentrates on developing a spaceborne synthetic aperture radar information extraction system for palm oil plantations in the Tropics. This will lead to objective figures that can be used internationally to create a policy implementation plan to sustainably reduce CO2 emission in the future.

  9. Diamond diffraction optics for CO2 lasers

    International Nuclear Information System (INIS)

    A laser ablation method for the formation of a phase microrelief on diamond optical diffraction components, intended for the far-IR range, was proposed and implemented. A one-dimensional diffraction component was made for CO2 laser radiation (λ = 10.6 μm): it was a cylindrical lens of 4 mmx4 mm aperture and with a focal length 25 mm. Microstructuring of the surface was performed by selective ablation etching of diamond with KrF excimer laser radiation (λ = 248 nm). The distribution of the field intensity in the focal region of the lens, its depth of focus, and the diffraction efficiency were determined. A high degree of correlation was found between the experimental characteristics of the lens and the results of computer modelling. (letters to the editor)

  10. CO2 laser-aided waste incineration

    International Nuclear Information System (INIS)

    Lasers are widely employed in laboratories and in certain industrial applications, notably for welding, cutting and surface treatments. This paper describes a new application, incineration, which appears warranted when the following features are required: high-temperature incineration (> 1500 deg C) with close-tolerance temperature control in an oxidizing medium while ensuring containment of toxic waste. These criteria correspond to the application presented here. Following a brief theoretical introduction concerning the laser/surface interaction, the paper describes the incineration of graphite waste contaminated with alpha-emitting radionuclides. Process feasibility has been demonstrated on a nonradioactive prototype capable of incinerating 10 kg-h-1 using a 7 kW CO2 laser. An industrial facility with the same capacity, designed to operate within the constraints of an alpha-tight glove box environment, is now at the project stage. Other types of applications with similar requirements may be considered. (authors). 3 refs., 7 figs

  11. CO2 laser therapy of rhinophyma

    Science.gov (United States)

    Voigt, Peggy; Jovanovic, Sergije; Sedlmaier, Benedikt W.

    2000-06-01

    Laser treatment of skin changes has become common practice in recent years. High absorption of the CO2 laser wavelength in water is responsible for its low penetration dpt in biological tissue. Shortening the tissue exposure time minimizes thermic side effects of laser radiation such as carbonization and coagulation. This can be achieved with scanner systems that move the focused laser beam over a defined area by microprocessor-controlled rapidly rotating mirrors. This enables controlled and reliable removal of certain dermal lesions, particularly hypertrophic scars, scars after common acne, wrinkles and rhinophyma. Laser ablation of rhinophyma is a stress-minimizing procedure for the surgeon and the patient, since it is nearly bloodless and can be performed under local anaesthesia. Cosmetically favorable reepithelization of the lasered surfaces is achieved within a very short period of time.

  12. Goodbye water use, tailings and Co2?

    Energy Technology Data Exchange (ETDEWEB)

    Stastny, R.P.

    2011-03-15

    Alberta Bitumen Link (ABL), a new integrated oilsands technology, is described. ABL combines the use of dimethyl ester (DME) as a solvent at lower temperatures in SAGD and the manufacture of DME by gasification of coal and asphaltenes so CO2 formation is reduced. The heat from the gasification process cogenerates electricity, while the produced DME is sent for use in the in-situ bitumen recovery. ABL finds the same mobility in bitumen stimulated with solvent at 80 C as a reservoir heated to 230 C by steam. The intellectual property now resides with Envirotech Consulting Inc. of Edmonton and Thermax Systems Co. of Japan and the technology is in small-scale testing. 1 fig.

  13. CO2 laser milling of hard tissue

    Science.gov (United States)

    Werner, Martin; Ivanenko, Mikhail; Harbecke, Daniela; Klasing, Manfred; Steigerwald, Hendrik; Hering, Peter

    2007-02-01

    Drilling of bone and tooth tissue belongs to recurrent medical procedures (screw- and pin-bores, bores for implant inserting, trepanation etc.). Small round bores can be in general quickly produced with mechanical drills. Problems arise however by angled drilling, by the necessity to fulfill the drilling without damaging of sensitive soft tissue beneath the bone, or by the attempt to mill precisely noncircular small cavities. We present investigations on laser hard tissue "milling", which can be advantageous for solving these problems. The "milling" is done with a CO2 laser (10.6 μm) with pulse duration of 50 - 100 μs, combined with a PC-controlled galvanic beam scanner and with a fine water-spray, which helps to avoid thermal side-effects. The damaging of underlying soft tissue can be prevented through control of the optical or acoustical ablation signal. The ablation of hard tissue is accompanied with a strong glowing, which is absent during the laser beam action on soft tissue. The acoustic signals from the diverse tissue types exhibit distinct differences in the spectral composition. Also computer image analysis could be a useful tool to control the operation. Laser "milling" of noncircular cavities with 1 - 4 mm width and about 10 mm depth is particularly interesting for dental implantology. In ex-vivo investigations we found conditions for fast laser "milling" of the cavities without thermal damage and with minimal tapering. It included exploration of different filling patterns (concentric rings, crosshatch, parallel lines and their combinations), definition of maximal pulse duration, repetition rate and laser power, optimal position of the spray. The optimized results give evidences for the applicability of the CO2 laser for biologically tolerable "milling" of deep cavities in the hard tissue.

  14. Characterization of YBCO superconductor sintered in CO2-containing atmosphere

    International Nuclear Information System (INIS)

    Stability of the YBCO superconductor toward reacting with CO2 in CO2/O2 gas mixtures during sintering was investigated as a function of the partial pressure of CO2 and temperature. Transport critical current density of the superconductor decreased drastically with increasing concentration of CO2 in the gas mixture. The microstructure and composition of the samples were investigated by transmission electron microscopy and energy-dispersive X-ray spectroscopy

  15. Effects of high CO2 concentrations on ecophysiologically different microorganisms

    International Nuclear Information System (INIS)

    We investigated the effect of increasing CO2 concentrations on the growth and viability of ecophysiologically different microorganisms to obtain information for a leakage scenario of CO2 into shallow aquifers related to the capture and storage of CO2 in deep geological sections. CO2 concentrations in the gas phase varied between atmospheric conditions and 80% CO2 for the aerobic strains Pseudomonas putida F1 and Bacillus subtilis 168 and up to 100% CO2 for the anaerobic strains Thauera aromatica K172 and Desulfovibrio vulgaris Hildenborough. Increased CO2 concentrations caused prolonged lag-phases, and reduced growth rates and cell yields; the extent of this effect was proportional to the CO2 concentration. Additional experiments with increasing CO2 concentrations and increasing pressure (1–5000 kPa) simulated situations occurring in deep CO2 storage sites. Living cell numbers decreased significantly within 24 h at pressures ≥1000 kPa, demonstrating a severe lethal effect for the combination of high pressure and CO2. - Highlights: ► Influence of high CO2 concentration on ecophysiologically different (aerobic, nitrate-reducing, sulphate-reducing) microorganisms. ► Investigation of growth and viability of two aerobic and two anaerobic model organisms. ► CO2 treatment also at elevated pressure up to 5000 kPa. ► Reduction of growth and viability at high CO2 concentrations. ► Sterilization at high pressure and high CO2 concentrations. - Increased CO2 concentrations, combined also with high pressure, adversely affected the growth and viability of four ecophysiological different microorganisms.

  16. Metabolic effects of CO2 anaesthesia in Drosophila melanogaster

    OpenAIRE

    Colinet, H.; Renault, D.

    2012-01-01

    Immobilization of insects is necessary for various experimental purposes, and CO2 exposure remains the most popular anaesthetic method in entomological research. A number of negative side effects of CO2 anaesthesia have been reported, but CO2 probably brings about metabolic modifications that are poorly known. In this work, we used GC/MS-based metabolic fingerprinting to assess the effect of CO2 anaesthesia in Drosophila melanogaster adults. We analysed metabolic variation of flies submitted ...

  17. Enhanced transport phenomena in CO2 sequestration and CO2 EOR

    NARCIS (Netherlands)

    Farajzadeh, R.

    2009-01-01

    The results of this thesis give insight into the (mass)-transfer during flow of gases, especially CO2, in various gas-liquid systems. A number of experiments was performed to investigate the transport phenomena through interfaces with and without surfactant monolayers. The observed phenomena have be

  18. University Rankings and Social Science

    OpenAIRE

    Marginson, S.

    2014-01-01

    University rankings widely affect the behaviours of prospective students and their families, university executive leaders, academic faculty, governments and investors in higher education. Yet the social science foundations of global rankings receive little scrutiny. Rankings that simply recycle reputation without any necessary connection to real outputs are of no common value. It is necessary that rankings be soundly based in scientific terms if a virtuous relationship between performance and...

  19. 离子液体捕集CO2%Capture of CO2 by Ionic Liquids

    Institute of Scientific and Technical Information of China (English)

    周凌云; 樊静; 王键吉

    2011-01-01

    CO2是导致温室效应的最主要成分,因此碳捕集技术的研究受到学术界和产业界的高度重视。离子液体具有不挥发、不燃烧、热稳定性好、溶解能力强、结构和性质可调节并可循环使用等特性,在CO2的吸收/分离领域展现了广阔的应用前景。本文系统地综述了近年来常规离子液体、功能化离子液体、支撑离子液体膜、聚合离子液体以及离子液体与分子溶剂的混合物在捕集CO2方面的研究进展;讨论了离子液体的阳离子结构、阴离子类型、烷基链长度、阴/阳离子的氟化程度和功能化、离子液体的负载作用和聚合效应以及体系的温度和压力对CO2选择性捕集性能的影响;分析了可能的捕集机理以及各种捕集方法的优点和缺点;提出了目前需要进一步研究的若干重要问题,并对其发展前景进行了展望。%Since CO2 is one of the most important greenhouse gases,the research and development in the carbon capture have long been the focus of many academic and industrial studies.Ionic liquids have a number of unique properties,such as no-volatility,non-flammation,recyclability,high thermal stability,strong solubility capacity,and the tunability of molecular structures and physicochemical properties.Thus they have promising application in absorption and separation of CO2.In this paper,the recent progress in the CO2 capture by using regular ionic liquids,task-specific ionic liquids,supported ionic-liquids membranes,polymerized ionic liquids and the mixtures of ionic liquids with some molecular solvents have been reviewed.The effects of cationic structure,anionic property,alkyl chain length,functionalization of both the cations and the anions,characteristics of the supported membranes,the polymerized degree of ionic liquids,temperature and pressure of the systems on the selective capture of CO2 are discussed in detail.The possible mechanisms for the capture and selective separation

  20. Decontamination of solid matrices using supercritical CO2: study of contaminant-additives-CO2

    International Nuclear Information System (INIS)

    This work deals with the decontamination of solid matrices by supercritical CO2 and more particularly with the study of the interactions between the surfactants and the CO2 in one part, and with the interactions between the contaminant and the surfactants in another part. The first part of this study has revealed the different interactions between the Pluronics molecules and the supercritical CO2. The diagrams graphs have shown that the pluronics (PE 6100, PE 8100 and PE 10100) present a solubility in the supercritical CO2 low but sufficient (0.1% m/m at 25 MPa and 313 K) for the studied application: the treatment of weak quantities of cerium oxide (or plutonium). An empirical approach based on the evolutions of the slops value and of the origin ordinates of the PT diagrams has been carried out to simulate the phase diagrams PT of the Pluronics. A modeling based on the state equations 'SAFT' (Statistical Associating Fluid Theory) has been studied in order to confirm the experimental results of the disorder points and to understand the role of the different blocks 'PEO' and 'PPO' in the behaviour of Pluronics; this modeling confirms the evolution of the slopes value with the 'CO2-phily' of the system. The measure of the surface tension in terms of the Pluronics concentration (PE 6100, 81000 and 10100) has shown different behaviours. For the PE 6100, the surface tension decreases when the surfactant concentration increases (at constant pressure and temperature); on the other hand, for the PE 8100 a slop rupture appears and corresponds to the saturation of the interface water/CO2 and allows then to determine the Interface Saturation Concentration (ISC). The ISC value (at constant pressure and temperature) increases with an increase of the 'CO2-phily'). The model hydrophilous medium being an approximation, it has been replaced by a solid polar phase of CeO2. A parallel has been established between the evolution of the surface tension between the water and the CO2 and

  1. Molecular simulations of CO2 and mixed CH4-CO2 hydrates intercalated on smectites.

    Science.gov (United States)

    Martos-Villa, Rubén; Sainz-Díaz, C. Ignacio; Mata Campo, M. Pilar

    2013-04-01

    Natural gas hydrates (NGH) are crystalline compounds consisting of methane molecules encaged in cavities of a hydrogen-bonded network of water molecules. Gas hydrates have a general formula X?nH2O, where X is the guest molecule within a water cage, and n is the hydration number per guest molecule. The crystal structure sI consists of 46 water molecules per unit cell, forming two dodecahedron (small 512) and six tetradecahedron (large 51262) cages and is formed when small guest molecules such as methane or carbon dioxide are trapped. Considerable amounts of methane hydrates can be found in permafrost regions and sediments of the ocean floor in outer continental margin regions where medium pressures, low temperatures and high methane gas concentration in water can be reached. Gas hydrates are important because hydrate decomposition would cause the methane release into atmosphere causing great impact on Earth's climate. On the other hand, these NGH are seen as a potential major energy resource. The recent increase in anthropogenic CO2 gas released to the atmosphere and its contribution to global warming, makes necessary to investigate new ways of CO2 storage. The possibility of replacing natural gas by CO2 from NGH has been investigated. There are thermodynamic evidences that support the replacement in hydrate at appropriate conditions. The comparison of their hydrate phase equilibrium conditions suggests the occurrence of a transition zone between both hydrate equilibrium curves where CO2 hydrates can exist while CH4 hydrates dissociate into methane gas and water. Any further investigation of the mixed CH4-CO2 gas hydrate properties could lead to major breakthroughs in the fields of unconventional resource production and carbon sequestration. Clay minerals are major constituents of ocean sediments, the study of interactions between these minerals with hydrates on the seafloor can be useful to determine variations on hydrate stability field, and to know the properties

  2. 40 CFR 98.423 - Calculating CO2 supply.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 20 2010-07-01 2010-07-01 false Calculating CO2 supply. 98.423 Section...) MANDATORY GREENHOUSE GAS REPORTING Suppliers of Carbon Dioxide § 98.423 Calculating CO2 supply. (a) Calculate the annual mass of CO2 captured, extracted, imported, or exported through each flow meter...

  3. A general method for calculating subsurface CO2 storage capacity

    NARCIS (Netherlands)

    Meer, L.G.H. van der; Egberts, P.J.P.

    2008-01-01

    In the past, lists of potential CO2 storage locations have been compiled purely on the basis of the capacity of the locations in terms of their CO2 solubility. However, in some of these locations, the injection of CO2 is commercially unfeasible because of their small average permeability. During the

  4. 46 CFR 108.451 - CO2 storage.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 4 2010-10-01 2010-10-01 false CO2 storage. 108.451 Section 108.451 Shipping COAST... Fire Extinguishing Systems Fixed Carbon Dioxide Fire Extinguishing Systems § 108.451 CO2 storage. (a) Except as provided in paragraph (b) of this section, each cylinder of a CO2 system must be outside...

  5. Acid Gas Capture Using CO2-Binding Organic Liquids

    Energy Technology Data Exchange (ETDEWEB)

    Heldebrant, David J.; Koech, Phillip K.; Rainbolt, James E.; Zheng, Feng

    2010-11-10

    Current chemical CO2 scrubbing technology is primarily aqueous alkanolamine based. These systems rapidly bind CO2 (forming water-soluble carbamate and bicarbonate salts) however, the process has serious disadvantages. The concentration of monoethanolamine rarely exceeds 30 wt % due to the corrosive nature of the solution, and this reduces the maximum CO2 volumetric (≤108 g/L) and gravimetric capacity (≤7 wt%) of the CO2 scrubber. The ≤30 wt % loading of ethanolamine also means that a large excess of water must be pumped and heated during CO2 capture and release, and this greatly increases the energy requirements especially considering the high specific heat of water (4 j/g-1K-1). Our approach is to switch to organic systems that chemically bind CO2 as liquid alkylcarbonate salts. Our CO2-binding organic liquids have higher CO2 solubility, lower specific heats, potential for less corrosion and lower binding energies for CO2 than aqueous systems. CO2BOLs also reversibly bind and release mixed sulfur oxides. Furthermore the CO2BOL system can be direct solvent replacements for any solvent based CO2 capture systems because they are commercially available reagents and because they are fluids they would not require extensive process re-engineering.

  6. Suppression of CO2-plasticization by semiinterpenetrating polymer network formation

    NARCIS (Netherlands)

    Bos, A.; Pünt, I.G.M.; Wessling, M.; Strathmann, H.

    1998-01-01

    CO2-induced plasticization may significantly spoil the membrane performance in high-pressure CO2/CH4 separations. The polymer matrix swells upon sorption of CO2, which accelerates the permeation of CH4. The polymer membrane looses its selectivity. To make membranes attractive for, for example, natur

  7. CO2 in Alberta - a vision of the future

    International Nuclear Information System (INIS)

    The potential to develop a province-wide infrastructure for carbon dioxide (CO2) collection and transmission was discussed. The petroleum industry's original interest in CO2 was its potential for enhanced oil recovery (EOR) for Alberta's depleted oil fields. However, new interest has stemmed from its perceived role in global climate change and the potentially negative business and economic implications of emitting CO2 into the atmosphere. It was suggested that the development of a province wide infrastructure to collect CO2 would address both interests. A simple screening of the reservoirs was carried out to determine if Alberta has the right oil reservoirs and sufficient CO2 supplies to support a large-scale CO2 infrastructure. The proposed infrastructure would consist of CO2 supplies from electrical power generation plants, CO2 trunklines, feeder pipelines to deliver CO2 from the trunklines to the field and the oil reservoirs where the CO2 would be injected. Such infrastructures already exist in Texas and Mexico where more than 1 billion scf per day of CO2 is used for EOR. This study compared the factors leading to a large-scale CO2 industry with factors in place during the 1970s and 1980s, when most of the hydrocarbon miscible floods were initiated in Alberta. It was concluded that the preliminary economics suggest that the concept has merit. 12 refs., 3 tabs., 9 figs

  8. A model for estimating CO2 solubility in aqueous alkanolamines

    DEFF Research Database (Denmark)

    Gabrielsen, Jostein; Michelsen, Michael Locht; Stenby, Erling Halfdan;

    2005-01-01

    of CO2 over an aqueous alkanolamine solution. Accurate values for the partial pressure of CO2 are obtained for a limited loading, temperature, and pressure range that is useful in modeling CO2 capture from coal-fired power plants. Heat of absorption values derived from the model agree with experimental...

  9. Rankings from Fuzzy Pairwise Comparisons

    NARCIS (Netherlands)

    Broek, van den Pim; Noppen, Joost; Mohammadian, M.

    2006-01-01

    We propose a new method for deriving rankings from fuzzy pairwise comparisons. It is based on the observation that quantification of the uncertainty of the pairwise comparisons should be used to obtain a better crisp ranking, instead of a fuzzified version of the ranking obtained from crisp pairwise

  10. University Rankings and Social Science

    Science.gov (United States)

    Marginson, Simon

    2014-01-01

    University rankings widely affect the behaviours of prospective students and their families, university executive leaders, academic faculty, governments and investors in higher education. Yet the social science foundations of global rankings receive little scrutiny. Rankings that simply recycle reputation without any necessary connection to real…

  11. Sensory Transduction of the CO2 Response of Guard Cells

    Energy Technology Data Exchange (ETDEWEB)

    Dr. Eduardo Zeiger

    2003-06-30

    Stomata have a key role in the regulation of gas exchange and intercellular CO2 concentrations of leaves. Guard cells sense internal and external signals in the leaf environment and transduce these signals into osmoregulatory processes that control stomatal apertures. This research proposal addresses the characterization of the sensory transduction of the CO2 signal in guard cells. Recent studies have shown that in Vicia leaves kept at constant light and temperature in a growth chamber, changes in ambient CO2 concentrations cause large changes in guard cell zeaxanthin that are linear with CO2-dependent changes in stomatal apertures. Research proposed here will test the hypothesis that zeaxanthin function as a transducer of CO2 signals in guard cells. Three central aspects of this hypothesis will be investigated: CO2 sensing by the carboxylation reaction of Rubisco in the guard cell chloroplast, which would modulate zeaxanthin concentrations via changes in lumen pH; transduction of the CO2 signal by zeaxanthin via a transducing cascade that controls guard cell osmoregulation; and blue light dependence of the CO2 signal transduction by zeaxanthin, required for the formation of an isomeric form of zeaxanthin that is physiologically active as a transducer. The role of Rubisco in CO2 sensing will be investigated in experiments characterizing the stomatal response to CO2 in the Arabidopsis mutants R100 and rca-, which have reduced rates of Rubisco-dependent carboxylation. The role of zeaxanthin as a CO2 transducer will be studied in npq1, a zeaxanthin-less mutant. The blue light-dependence of CO2 sensing will be studied in experiments characterizing the stomatal response to CO2 under red light. Arabidopsis mutants will also be used in further studies of an acclimation of the stomatal response to CO2, and a possible role of the xanthophyll cycle of the guard cell chloroplast in acclimations of the stomatal response to CO2. Studies on the osmoregulatory role of sucrose in

  12. Mode selection of China's urban heating and its potential for reducing energy consumption and CO2 emission

    International Nuclear Information System (INIS)

    China's carbon dioxide (CO2) emission ranks the highest in the world. CO2 emission from urban central heating, which has an average annual growth rate of 10.3%, is responsible for 4.4% of China's total CO2 emission. The current policy for improving urban central heating focuses on replacing coal with natural gas. This paper analyzes the existing situation and problems pertaining to urban heating, and evaluates the potential for reducing energy consumption and CO2 emission by heat pump heating. The results show that the current policy of replacing coal with natural gas for urban central heating decreases energy consumption and CO2 emission by 16.6% and 63.5%, respectively. On the other hand, replacing coal-based urban central heating with heat pump heating is capable of decreasing energy consumption and CO2 emission by 57.6% and 81.4%, respectively. Replacing both urban central and decentralized heating with heat pump heating can lead to 67.7% and 85.8% reduction in energy consumption and CO2 emission, respectively. The decreases in CO2 emission will account for 24.5% of China's target to reduce total CO2 emission by 2020. - Highlights: • Existing situation and problems of urban heating in China. • Feasibility of heat pump heating in China. • Potential of energy saving and emission reduction for heat pump heating. • China should adjust urban heating strategy. • Replacing urban central heating and decentralized heating with heat pump heating

  13. Simplified Data Envelopment Analysis: What Country Won the Olympics, and How about our CO2 Emissions?

    Directory of Open Access Journals (Sweden)

    Alexander Vaninsky

    2013-07-01

    Full Text Available This paper introduces a simplified version of Data Envelopment Analysis - a conventional approach to evaluating the performance and ranking of competitive objects characterized by two groups of factors acting in opposite directions: inputs and outputs. Examples of DEA applications discussed in this paper include the London 2012 Olympic Games and the dynamics of the United States’ environmental performance. In the first example, we find a team winner and rank the teams; in the second, we analyze the dynamics of CO2 emissions adjusted to the gross domestic product, population, and energy consumption. Adding a virtual Perfect Object – one having the greatest outputs and smallest inputs - we greatly simplify the DEA computational procedure by eliminating the Linear Programming algorithm. Simplicity of computations makes the suggested approach attractive for educational purposes, in particular, for use in Quantitative Reasoning courses.

  14. Determining CO2 storage potential during miscible CO2 enhanced oil recovery: noble gas and stable isotope tracers

    Science.gov (United States)

    Shelton, Jenna L.; McIntosh, Jennifer C.; Hunt, Andrew; Beebe, Thomas L; Parker, Andrew D; Warwick, Peter; Drake, Ronald; John E. McCray

    2016-01-01

    Rising atmospheric carbon dioxide (CO2) concentrations are fueling anthropogenic climate change. Geologic sequestration of anthropogenic CO2 in depleted oil reservoirs is one option for reducing CO2 emissions to the atmosphere while enhancing oil recovery. In order to evaluate the feasibility of using enhanced oil recovery (EOR) sites in the United States for permanent CO2 storage, an active multi-stage miscible CO2 flooding project in the Permian Basin (North Ward Estes Field, near Wickett, Texas) was investigated. In addition, two major natural CO2 reservoirs in the southeastern Paradox Basin (McElmo Dome and Doe Canyon) were also investigated as they provide CO2 for EOR operations in the Permian Basin. Produced gas and water were collected from three different CO2 flooding phases (with different start dates) within the North Ward Estes Field to evaluate possible CO2 storage mechanisms and amounts of total CO2 retention. McElmo Dome and Doe Canyon were sampled for produced gas to determine the noble gas and stable isotope signature of the original injected EOR gas and to confirm the source of this naturally-occurring CO2. As expected, the natural CO2 produced from McElmo Dome and Doe Canyon is a mix of mantle and crustal sources. When comparing CO2 injection and production rates for the CO2 floods in the North Ward Estes Field, it appears that CO2 retention in the reservoir decreased over the course of the three injections, retaining 39%, 49% and 61% of the injected CO2 for the 2008, 2010, and 2013 projects, respectively, characteristic of maturing CO2 miscible flood projects. Noble gas isotopic composition of the injected and produced gas for the flood projects suggest no active fractionation, while δ13CCO2 values suggest no active CO2 dissolution into formation water, or mineralization. CO2 volumes capable of dissolving in residual formation fluids were also estimated along with the potential to store pure-phase supercritical CO2. Using a combination of

  15. CO2 storage capacity estimation: Methodology and gaps

    Science.gov (United States)

    Bachu, S.; Bonijoly, D.; Bradshaw, J.; Burruss, R.; Holloway, S.; Christensen, N.P.; Mathiassen, O.M.

    2007-01-01

    Implementation of CO2 capture and geological storage (CCGS) technology at the scale needed to achieve a significant and meaningful reduction in CO2 emissions requires knowledge of the available CO2 storage capacity. CO2 storage capacity assessments may be conducted at various scales-in decreasing order of size and increasing order of resolution: country, basin, regional, local and site-specific. Estimation of the CO2 storage capacity in depleted oil and gas reservoirs is straightforward and is based on recoverable reserves, reservoir properties and in situ CO2 characteristics. In the case of CO2-EOR, the CO2 storage capacity can be roughly evaluated on the basis of worldwide field experience or more accurately through numerical simulations. Determination of the theoretical CO2 storage capacity in coal beds is based on coal thickness and CO2 adsorption isotherms, and recovery and completion factors. Evaluation of the CO2 storage capacity in deep saline aquifers is very complex because four trapping mechanisms that act at different rates are involved and, at times, all mechanisms may be operating simultaneously. The level of detail and resolution required in the data make reliable and accurate estimation of CO2 storage capacity in deep saline aquifers practical only at the local and site-specific scales. This paper follows a previous one on issues and development of standards for CO2 storage capacity estimation, and provides a clear set of definitions and methodologies for the assessment of CO2 storage capacity in geological media. Notwithstanding the defined methodologies suggested for estimating CO2 storage capacity, major challenges lie ahead because of lack of data, particularly for coal beds and deep saline aquifers, lack of knowledge about the coefficients that reduce storage capacity from theoretical to effective and to practical, and lack of knowledge about the interplay between various trapping mechanisms at work in deep saline aquifers. ?? 2007 Elsevier Ltd

  16. CO(2) homeostasis during periodic breathing in obstructive sleep apnea.

    Science.gov (United States)

    Berger, K I; Ayappa, I; Sorkin, I B; Norman, R G; Rapoport, D M; Goldring, R M

    2000-01-01

    The contribution of apnea to chronic hypercapnia in obstructive sleep apnea (OSA) has not been clarified. Using a model (D. M. Rapoport, R. G. Norman, and R. M. Goldring. J. Appl. Physiol. 75: 2302-2309, 1993), we previously illustrated failure of CO(2) homeostasis during periodic breathing resulting from temporal dissociation between ventilation and perfusion ("temporal V/Q mismatch"). This study measures acute kinetics of CO(2) during periodic breathing and addresses interapnea ventilatory compensation for maintenance of CO(2) homeostasis in 11 patients with OSA during daytime sleep (37-171 min). Ventilation and expiratory CO(2) and O(2) fractions were measured on a breath-by-breath basis by means of a tight-fitting full facemask. Calculations included CO(2) excretion, metabolic CO(2) production, and CO(2) balance (metabolic CO(2) production - exhaled CO(2)). CO(2) balance was tabulated for each apnea/hypopnea event-interevent cycle and as a cumulative value during sleep. Cumulative CO(2) balance varied (-3,570 to +1,388 ml). Positive cumulative CO(2) balance occurred in the absence of overall hypoventilation during sleep. For each cycle, positive CO(2) balance occurred despite increased interevent ventilation to rates as high as 45 l/min. This failure of CO(2) homeostasis was dependent on the event-to-interevent duration ratio. The results demonstrate that 1) periodic breathing provides a mechanism for acute hypercapnia in OSA, 2) acute hypercapnia during periodic breathing may occur without a decrease in average minute ventilation, supporting the presence of temporal V/Q mismatch, as predicted from our model, and 3) compensation for CO(2) accumulation during apnea/hypopnea may be limited by the duration of the interevent interval. The relationship of this acute hypercapnia to sustained chronic hypercapnia in OSA remains to be further explored. PMID:10642388

  17. CO 2 Capture Rate Sensitivity Versus Purchase of CO 2 Quotas. Optimizing Investment Choice for Electricity Sector

    OpenAIRE

    Coussy Paula; Raynal Ludovic

    2014-01-01

    International audience Carbon capture technology (and associated storage), applied to power plants, reduces atmospheric CO2 emissions. This article demonstrates that, in the particular case of the deployment phase of CO2 capture technology during which CO2 quota price may be low, capturing less than 90% of total CO2 emissions from power plants can be economically attractive. Indeed, for an electric power company capture technology is interesting, only if the discounted marginal cost of cap...

  18. Thermodynamic and kinetic processes associated with CO 2-sequestration and CO 2-enhanced coalbed methane production from unminable coal seams

    OpenAIRE

    Busch, Andreas

    2005-01-01

    The present thesis investigates the thermodynamic and kinetic processes associated with gas sorption (CO2, CH4) on coal. It is incorporated into a research field which studies CO2-sequestration in combination with CO2-enhanced coalbed methane production in unminable coal seams. This combination is regarded as a viable and promising option to reduce anthropogenic CO2-emissions. At the moment numerous world-wide research projects investigate the feasibility of this concept under different geolo...

  19. CO 2 Capture Rate Sensitivity Versus Purchase of CO 2 Quotas. Optimizing Investment Choice for Electricity Sector

    OpenAIRE

    Paula Coussy; Ludovic Raynal

    2014-01-01

    Carbon capture technology (and associated storage), applied to power plants, reduces atmospheric CO2 emissions. This article demonstrates that, in the particular case of the deployment phase of CO2 capture technology during which CO2 quota price may be low, capturing less than 90% of total CO2 emissions from power plants can be economically attractive. Indeed, for an electric power company capture technology is interesting, only if the discounted marginal cost of capture is lower than the dis...

  20. A novel approach for independent budgeting of fossil fuel CO2 over Europe by 14CO2 observations

    OpenAIRE

    LEVIN Ingeborg; Kromer, Bernd; Schmidt, Martina; Sartorius, Hartmut

    2003-01-01

    Long-term atmospheric 14CO2 observations are deployed to quantify fossil fuel derived CO2 concentrations at a regional polluted site, and at a continental mountain station in south-west Germany. Fossil fuel CO2 emission rates for the relevant catchment areas are obtained by applying the Radon-Tracer-Method. They are shown to compare well with statistical emissions inventories but reveal a larger seasonality than assumed earlier, thus contributing significantly to the observed CO2 seasonal cyc...

  1. Separation of CO2 from CH4 and CO2 capture in the presence of water vapour in NOTT-400

    International Nuclear Information System (INIS)

    From a binary equimolar gas-mixture of CO2 and CH4, NOTT-400 shows CO2 separation from CH4. By kinetic uptake experiments, this material confirms a maximum of 4.3 wt% CO2 capture at 30 C and a significant 2-fold increase (∼9.3 wt%) in CO2 capture under 40% relative humidity of water vapour. (authors)

  2. On the proportionality between global temperature change and cumulative CO2 emissions during periods of net negative CO2 emissions

    Science.gov (United States)

    Zickfeld, Kirsten; MacDougall, Andrew H.; Damon Matthews, H.

    2016-05-01

    Recent research has demonstrated that global mean surface air warming is approximately proportional to cumulative CO2 emissions. This proportional relationship has received considerable attention, as it allows one to calculate the cumulative CO2 emissions (‘carbon budget’) compatible with temperature targets and is a useful measure for model inter-comparison. Here we use an Earth system model to explore whether this relationship persists during periods of net negative CO2 emissions. Negative CO2 emissions are required in the majority of emissions scenarios limiting global warming to 2 °C above pre-industrial, with emissions becoming net negative in the second half of this century in several scenarios. We find that for model simulations with a symmetric 1% per year increase and decrease in atmospheric CO2, the temperature change (ΔT) versus cumulative CO2 emissions (CE) relationship is nonlinear during periods of net negative emissions, owing to the lagged response of the deep ocean to previously increasing atmospheric CO2. When corrected for this lagged response, or if the CO2 decline is applied after the system has equilibrated with the previous CO2 increase, the ΔT versus CE relationship is close to linear during periods of net negative CO2 emissions. A proportionality constant—the transient climate response to cumulative carbon emissions (TCRE)‑ can therefore be calculated for both positive and net negative CO2 emission periods. We find that in simulations with a symmetric 1% per year increase and decrease in atmospheric CO2 the TCRE is larger on the upward than on the downward CO2 trajectory, suggesting that positive CO2 emissions are more effective at warming than negative emissions are at subsequently cooling. We also find that the cooling effectiveness of negative CO2 emissions decreases if applied at higher atmospheric CO2 concentrations.

  3. End tidal CO2 versus arterial CO2 monitoring in patients undergoing coronary artery bypass graft

    Directory of Open Access Journals (Sweden)

    Hassani E

    2009-12-01

    Full Text Available "n Normal 0 false false false EN-US X-NONE AR-SA MicrosoftInternetExplorer4 /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin:0in; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-fareast-font-family:"Times New Roman"; mso-fareast-theme-font:minor-fareast; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:Arial; mso-bidi-theme-font:minor-bidi;} Background: Measuring end tidal carbon dioxide (ETCo2 is one of the methods used for estimating arterial carbon dioxide (PaCo2 during general anesthesia. ETCo2 measurements maybe obviate the need for repeating arterial puncture for determination of arterial PaCo2. This study performed to determine the accuracy of ETCo2 levels as a measure of PaCo2 levels in patients undergoing coronary artery bypass graft and also to evaluate variation of the gradient between PaCo2 and ETCo2, peri- cardiopulmonary bypass operation."n"nMethods: In a prospective, cross-sectional study, a total of 40 patients with age 57±11 (35-73 years old undergoing coronary artery bypass graft were enrolled. ETCo2 levels (mmHg were recorded using side stream capnography at the time of arterial blood gas sampling, before (T0 and after (T1 cardiopulmonary bypass."n"nResults: Mean P(a-ETCo2 at T0 was 4.3±4.4mmHg, with the mean PaCo2, 33±6mmHg and mean ETCo2, 29±5mmHg and these values at T1 were 4.5±4.1mmHg, 33±5mmHg and 29±2mmHg respectively. There was no variation of the mean gradient (PaCo2-PETCo2 during, before and after cardiopulmonary bypass (p>0.870. Significant correlation was found between ETCo2 and PaCo2 at T0 and T1 (r=0.754 and 0

  4. Geologic CO2 Sequestration: Predicting and Confirming Performance in Oil Reservoirs and Saline Aquifers

    Science.gov (United States)

    Johnson, J. W.; Nitao, J. J.; Newmark, R. L.; Kirkendall, B. A.; Nimz, G. J.; Knauss, K. G.; Ziagos, J. P.

    2002-05-01

    Reducing anthropogenic CO2 emissions ranks high among the grand scientific challenges of this century. In the near-term, significant reductions can only be achieved through innovative sequestration strategies that prevent atmospheric release of large-scale CO2 waste streams. Among such strategies, injection into confined geologic formations represents arguably the most promising alternative; and among potential geologic storage sites, oil reservoirs and saline aquifers represent the most attractive targets. Oil reservoirs offer a unique "win-win" approach because CO2 flooding is an effective technique of enhanced oil recovery (EOR), while saline aquifers offer immense storage capacity and widespread distribution. Although CO2-flood EOR has been widely used in the Permian Basin and elsewhere since the 1980s, the oil industry has just recently become concerned with the significant fraction of injected CO2 that eludes recycling and is therefore sequestered. This "lost" CO2 now has potential economic value in the growing emissions credit market; hence, the industry's emerging interest in recasting CO2 floods as co-optimized EOR/sequestration projects. The world's first saline aquifer storage project was also catalyzed in part by economics: Norway's newly imposed atmospheric emissions tax, which spurred development of Statoil's unique North Sea Sleipner facility in 1996. Successful implementation of geologic sequestration projects hinges on development of advanced predictive models and a diverse set of remote sensing, in situ sampling, and experimental techniques. The models are needed to design and forecast long-term sequestration performance; the monitoring techniques are required to confirm and refine model predictions and to ensure compliance with environmental regulations. We have developed a unique reactive transport modeling capability for predicting sequestration performance in saline aquifers, and used it to simulate CO2 injection at Sleipner; we are now

  5. Fourth-rank cosmology

    International Nuclear Information System (INIS)

    Some cosmological implications of the recently proposed fourth-rank theory of gravitation are studied. The model exhibits the possibility of being free from the horizon and flatness problems at the price of introducing a negative pressure. The field equations we obtain are compatible with kobs=0 and Ωobstclas approx. 1020tPlanck approx. 10-23s. When interpreted at the light of General Relativity the treatment is shown to be almost equivalent to that of the standard model of cosmology combined with the inflationary scenario. Hence, an interpretation of the negative pressure hypothesis is provided. (author). 8 refs

  6. Rankings, creatividad y urbanismo

    OpenAIRE

    JOAQUÍN SABATÉ; MANUEL TIRONI

    2008-01-01

    La competencia entre ciudades constituye uno de los factores impulsores de procesos de renovación urbana y los rankings han devenido instrumentos de medida de la calidad de las ciudades. Nos detendremos en el caso de un antiguo barrio industrial hoy en vías de transformación en distrito "creativo" por medio de una intervención urbanística de gran escala. Su análisis nos descubre tres claves críticas. En primer lugar, nos obliga a plantearnos la definición de innovación urbana y cómo se integr...

  7. Combustion characteristics of Mg−CO2 counterflow diffusion flames

    OpenAIRE

    Fukuchi, Aporo; Kawashima, Masaru; Yuasa, Saburo

    1996-01-01

    To examine the details of the Mg−CO2 combustion consisting of the gas-phase reactions and the surface reactions, we tried to separate the Mg−CO2 flame from the surface reactions. For this purpose, we formed a stable Mg−CO2 counterflow diffusion flame between the Mg vapor and a CO2 stream by using a Mg vaporizer with many small ejection holes.The Mg−CO2 counterflow diffusion flames contained two types of flames: the luminous flame and the dark flame. In the luminous flame, the homogeneous reac...

  8. Trends in global CO2 emissions: 2012 report

    OpenAIRE

    OLIVIER Jos; Janssens-Maenhout, Greet; Peters, Jeroen

    2012-01-01

    Global emissions of carbon dioxide (CO2) – the main cause of global warming – increased by 3% in 2011, reaching an all-time high of 34 billion tonnes in 2011. In 2011, China’s average per capita carbon dioxide (CO2) emissions increased by 9% to 7.2 tonnes CO2¬, whereas these emissions in the European Union declined by 4 % to 7.5 tonnes CO2, bringing for the first time Europe’s and China’s CO2 emissions on similar levels. China, the world’s most populous country, is now well within the 6 to ...

  9. A Quantitative Investigation of CO2 Sequestration by Mineral Carbonation

    OpenAIRE

    Mohammad, Muneer; Ehsani, Mehrdad

    2015-01-01

    Anthropogenic activities have led to a substantial increase in carbon dioxide (CO2), a greenhouse gas (GHG), contributing to heightened concerns of global warming. In the last decade alone CO2 emissions increased by 2.0 ppm/yr. globally. In the year 2009, United States and China contributed up to 43.4% of global CO2 emissions. CO2 capture and sequestration have been recognized as promising solutions to mitigate CO2 emissions from fossil fuel based power plants. Typical techniques for carbon c...

  10. Carbon monoxide: A quantitative tracer for fossil fuel CO2?

    OpenAIRE

    Gamnitzer, Ulrike; Karstens, Ute; Kromer, Bernd; Neubert, Rolf; Meijer, Harro; Schroeder, Hartwig; LEVIN Ingeborg

    2006-01-01

    Carbon monoxide (CO), carbon dioxide (CO2), and radiocarbon (14CO2) measurements have been made in Heidelberg from 2001 to 2004 in order to determine the regional fossil fuel CO2 component and to investigate the application of CO as a quantitative tracer for fossil fuel CO2 (CO2(foss)). The observations were compared with model estimates simulated with the regional transport model REMO at 0.5°x0.5° resolution in Europe for 2002. These estimates are based on two available emissions inventories...

  11. Floral CO2 reveals flower profitability to moths.

    Science.gov (United States)

    Thom, Corinna; Guerenstein, Pablo G; Mechaber, Wendy L; Hildebrand, John G

    2004-06-01

    The hawkmoth Manduca sexta (Lepidoptera: Sphingidae), an experimentally favorable Lepidopteran that is highly sensitive to carbon dioxide (CO2), feeds on the nectar of a range of flowering plants, such as Datura wrightii (Solanaceae). Newly opened Datura flowers give off dramatically elevated levels of CO2 and offer ample nectar. Thus, floral CO2 emission could indicate food-source profitability. This study documents that foraging Manduca moths prefer surrogate flowers that emit high levels of CO2, characteristic of newly opened Datura flowers. We show for the first time that CO2 may play an important role in the foraging behavior of nectar-feeding insects. PMID:15303329

  12. Detection of CO2 leaks from carbon capture and storage sites with combined atmospheric CO2 and O-2 measurements

    NARCIS (Netherlands)

    van Leeuwen, Charlotte; Meijer, Harro A. J.

    2015-01-01

    This paper presents a transportable instrument that simultaneously measures the CO2 and (relative) O-2 concentration of the atmosphere with the purpose to aid in the detection of CO2 leaks from CCS sites. CO2 and O-2 are coupled in most processes on earth (e.g., photosynthesis, respiration and fossi

  13. Half-metallic {Co2MnSi/Co2FeSi} multilayered Heusler electrodes in magnetic tunnel junctions

    International Nuclear Information System (INIS)

    It is demonstrated that the atomic ordering of Co2FeSi can significantly be improved in terms of magnetization and tunnel magnetoresistance using multilayered {Co2MnSi5nm/Co2FeSi5nm}10 full-Heusler magnetic electrodes in magnetic tunnel junctions

  14. Effects of Atmospheric CO2 Enrichment on Soil CO2 Efflux in a Young Longleaf Pine System

    Directory of Open Access Journals (Sweden)

    G. Brett Runion

    2012-01-01

    Full Text Available The southeastern landscape is composed of agricultural and forest systems that can store carbon (C in standing biomass and soil. Research is needed to quantify the effects of elevated atmospheric carbon dioxide (CO2 on terrestrial C dynamics including CO2 release back to the atmosphere and soil sequestration. Longleaf pine savannahs are an ecologically and economically important, yet understudied, component of the southeastern landscape. We investigated the effects of ambient and elevated CO2 on soil CO2 efflux in a young longleaf pine system using a continuous monitoring system. A significant increase (26.5% in soil CO2 efflux across 90 days was observed under elevated CO2; this occurred for all weekly and daily averages except for two days when soil temperature was the lowest. Soil CO2 efflux was positively correlated with soil temperature with a trend towards increased efflux response to temperature under elevated CO2. Efflux was negatively correlated with soil moisture and was best represented using a quadratic relationship. Soil CO2 efflux was not correlated with root biomass. Our data indicate that, while elevated CO2 will increase feedback of CO2 to the atmosphere via soil efflux, terrestrial ecosystems will remain potential sinks for atmospheric CO2 due to greater biomass production and increased soil C sequestration.

  15. CO2 niet meer dan genoeg: Teelt van Tomaat in 2012 bij Improvement Centre met lichtafhankelijk doseren van CO2

    NARCIS (Netherlands)

    Gelder, de A.; Warmenhoven, M.G.; Dieleman, J.A.; Klapwijk, P.; Baar, van P.H.

    2014-01-01

    Wageningen UR Glastuinbouw heeft met financiering van Kas als Energiebron en Samenwerken aan Vaardigheden onderzoek gedaan naar efficienter gebruik van CO2. In een kasproef bij GreenQ/Improvement Centre is een CO2 doseerstrategie getest, waarbij iets meer CO2 wordt gegeven dan er op basis van de hoe

  16. CO2 (dry ice) cleaning system

    Science.gov (United States)

    Barnett, Donald M.

    1995-01-01

    Tomco Equipment Company has participated in the dry ice (solid carbon dioxide, CO2) cleaning industry for over ten years as a pioneer in the manufacturer of high density, dry ice cleaning pellet production equipment. For over four years Tomco high density pelletizers have been available to the dry ice cleaning industry. Approximately one year ago Tomco introduced the DI-250, a new dry ice blast unit making Tomco a single source supplier for sublimable media, particle blast, cleaning systems. This new blast unit is an all pneumatic, single discharge hose device. It meters the insertion of 1/8 inch diameter (or smaller), high density, dry ice pellets into a high pressure, propellant gas stream. The dry ice and propellant streams are controlled and mixed from the blast cabinet. From there the mixture is transported to the nozzle where the pellets are accelerated to an appropriate blasting velocity. When directed to impact upon a target area, these dry ice pellets have sufficient energy to effectively remove most surface coatings through dry, abrasive contact. The meta-stable, dry ice pellets used for CO2 cleaning, while labeled 'high density,' are less dense than alternate, abrasive, particle blast media. In addition, after contacting the target surface, they return to their equilibrium condition: a superheated gas state. Most currently used grit blasting media are silicon dioxide based, which possess a sharp tetrahedral molecular structure. Silicon dioxide crystal structures will always produce smaller sharp-edged replicas of the original crystal upon fracture. Larger, softer dry ice pellets do not share the same sharp-edged crystalline structures as their non-sublimable counterparts when broken. In fact, upon contact with the target surface, dry ice pellets will plastically deform and break apart. As such, dry ice cleaning is less harmful to sensitive substrates, workers and the environment than chemical or abrasive cleaning systems. Dry ice cleaning system

  17. P67-phox (NCF2 lacking exons 11 and 12 is functionally active and leads to an extremely late diagnosis of chronic granulomatous disease (CGD.

    Directory of Open Access Journals (Sweden)

    Joachim Roesler

    Full Text Available Two brothers in their fifties presented with a medical history of suspected fungal allergy, allergic bronchopulmonary aspergillosis, alveolitis, and invasive aspergillosis and pulmonary fistula, respectively. Eventually, after a delay of 50 years, chronic granulomatous disease (CGD was diagnosed in the index patient. We found a new splice mutation in the NCF2 (p67-phox gene, c.1000 + 2T → G, that led to several splice products one of which lacked exons 11 and 12. This deletion was in frame and allowed for remarkable residual NADPH oxidase activity as determined by transduction experiments using a retroviral vector. We conclude that p67-phox which lacks the 34 amino acids encoded by the two exons can still exert considerable functional activity. This activity can partially explain the long-term survival of the patients without adequate diagnosis and treatment, but could not prevent progressing lung damage.

  18. Economics show CO2 EOR potential in central Kansas

    Science.gov (United States)

    Dubois, M.K.; Byrnes, A.P.; Pancake, R.E.; Willhite, G.P.; Schoeling, L.G.

    2000-01-01

    Carbon dioxide (CO2) enhanced oil recovery (EOR) may be the key to recovering hundreds of millions of bbl of trapped oil from the mature fields in central Kansas. Preliminary economic analysis indicates that CO2 EOR should provide an internal rate of return (IRR) greater than 20%, before income tax, assuming oil sells for $20/bbl, CO2 costs $1/Mcf, and gross utilization is 10 Mcf of CO2/bbl of oil recovered. If the CO2 cost is reduced to $0.75/Mcf, an oil price of $17/bbl yields an IRR of 20%. Reservoir and economic modeling indicates that IRR is most sensitive to oil price and CO2 cost. A project requires a minimum recovery of 1,500 net bbl/acre (about 1 million net bbl/1-mile section) under a best-case scenario. Less important variables to the economics are capital costs and non-CO2 related lease operating expenses.

  19. What does CO2 geological storage really mean?

    International Nuclear Information System (INIS)

    It is now accepted that human activities are disturbing the carbon cycle of the planet. CO2, a greenhouse gas, has accumulated in the atmosphere where it contributes to climate change. Amongst the spectrum of short term measures that need to be urgently implemented to mitigate climate change, CO2 capture and storage can play a decisive role as it could contribute 33% of the CO2 reduction needed by 2050. This document aims to explain this solution by answering the following questions: where and how much CO2 can we store underground, How can we transport and inject large quantities of CO2, What happens to the CO2 once in the storage reservoir? Could CO2 leak from the reservoir and if so, what might be the consequences? How can we monitor the storage site at depth and at the surface? What safety criteria need to be imposed and respected? (A.L.B.)

  20. Fire hazards and CO2 laser resurfacing.

    Science.gov (United States)

    Wald, D; Michelow, B J; Guyuron, B; Gibb, A A

    1998-01-01

    The purpose of this study was to investigate the fire risk of laser resurfacing in the presence of supplemental oxygen. This study aims at defining safety parameters of variables such as laser energy level, oxygen flow rate, and "oxygen to laser target distance" when oxygen is delivered through a nasal cannula or nasopharyngeal tube. The typical operating room environment was simulated in the laboratory using the Yucatan minipig animal model. The energy source was a Coherent Ultrapulse CO2 laser. It was found that combustion did not occur at laser settings of 500 mJ, 50 W, 100 kHz, and a density of 5, used in conjunction with an oxygen flow rate of 6 liter/minute with the target area as close as 0.5 cm to the oxygen delivery. A total of 400 computer pattern generator treatments were delivered using this energy setting without observation of any combustion (p free of combustible fuels. Despite this assurance, laser mishaps are serious because they lead to both morbidity and mortality. It is our recommendation that close attention be constantly paid to all details, thus reducing the hazard potential of laser energy on local factors in an oxygen-rich environment. PMID:9427936

  1. A centrifuge CO2 pellet cleaning system

    Science.gov (United States)

    Foster, C. A.; Fisher, P. W.; Nelson, W. D.; Schechter, D. E.

    1995-01-01

    An advanced turbine/CO2 pellet accelerator is being evaluated as a depaint technology at Oak Ridge National Laboratory (ORNL). The program, sponsored by Warner Robins Air Logistics Center (ALC), Robins Air Force Base, Georgia, has developed a robot-compatible apparatus that efficiently accelerates pellets of dry ice with a high-speed rotating wheel. In comparison to the more conventional compressed air 'sandblast' pellet accelerators, the turbine system can achieve higher pellet speeds, has precise speed control, and is more than ten times as efficient. A preliminary study of the apparatus as a depaint technology has been undertaken. Depaint rates of military epoxy/urethane paint systems on 2024 and 7075 aluminum panels as a function of pellet speed and throughput have been measured. In addition, methods of enhancing the strip rate by combining infra-red heat lamps with pellet blasting and by combining the use of environmentally benign solvents with the pellet blasting have also been studied. The design and operation of the apparatus will be discussed along with data obtained from the depaint studies.

  2. Advanced turbine/CO2 pellet accelerator

    International Nuclear Information System (INIS)

    An advanced turbine/CO2 pellet accelerator is being evaluated as a depaint technology at Oak Ridge National Laboratory. The program, sponsored by Warner Robins Air Logistics Center, Robins Air Force Base, Georgia, has developed a robot-compatible apparatus that efficiently accelerates pellets of dry ice with a high-speed rotating wheel. In comparison to the more conventional compressed air sandblast pellet accelerators, the turbine system can achieve higher pellet speeds, has precise speed control, and is more than ten times as efficient. A preliminary study of the apparatus as a depaint technology has been undertaken. Depaint rates of military epoxy/urethane paint systems on 2024 and 7075 aluminum panels as a function of pellet speed and throughput have been measured. In addition, methods of enhancing the strip rate by combining infra-red heat lamps with pellet blasting have also been studied. The design and operation of the apparatus will be discussed along with data obtained from the depaint studies. Applications include removal of epoxy-based points from aircraft and the cleaning of surfaces contaminated with toxic, hazardous, or radioactive substances. The lack of a secondary contaminated waste stream is of great benefit

  3. Development of optical MEMS CO2 sensors

    Science.gov (United States)

    McNeal, Mark P.; Moelders, Nicholas; Pralle, Martin U.; Puscasu, Irina; Last, Lisa; Ho, William; Greenwald, Anton C.; Daly, James T.; Johnson, Edward A.; George, Thomas

    2002-09-01

    Inexpensive optical MEMS gas and chemical sensors offer chip-level solutions to environmental monitoring, industrial health and safety, indoor air quality, and automobile exhaust emissions monitoring. Previously, Ion Optics, Inc. reported on a new design concept exploiting Si-based suspended micro-bridge structures. The devices are fabricated using conventional CMOS compatible processes. The use of photonic bandgap (PBG) crystals enables narrow band IR emission for high chemical selectivity and sensitivity. Spectral tuning was accomplished by controlling symmetry and lattice spacing of the PBG structures. IR spectroscopic studies were used to characterize transmission, absorption and emission spectra in the 2 to 20 micrometers wavelength range. Prototype designs explored suspension architectures and filament geometries. Device characterization studies measured drive and emission power, temperature uniformity, and black body detectivity. Gas detection was achieved using non-dispersive infrared (NDIR) spectroscopic techniques, whereby target gas species were determined from comparison to referenced spectra. A sensor system employing the emitter/detector sensor-chip with gas cell and reflective optics is demonstrated and CO2 gas sensitivity limits are reported.

  4. Plywood Inlays Thourgh CO2 Laser Cutting

    Science.gov (United States)

    Pires, Margarida C.; Araujo, J. L.; Teixeira, M. Ribau; Rodrigues, F. Carvalho

    1989-07-01

    Furniture with inlays is rather expensive. This is so on two accounts: Firstly, furniture with inlays is generally manufactured with solid wood.Secondly,wood carving and figure cutting are both time consuming and they produce a high rate of rejections. To add to it all the cutting and carving of minute figures requires an outstanding craftmanship. In fact the craftman is in most instance the artist and also the manufacturer. While desiring that the high artistic level is maintained in the industry the search for new method to produce inlays for furniture in not son expensive materials and to produce them in a repetitive and flexible way laser cutting of plywood was found to be quite suitable. This paper presents the charts for CO2 laser cutting of both positive and negatives in several types of plywood. The main problem is not so much the cutting of the positive and negatives pieces but to be able to cut the piece in a way that the fitting is done without any problems caused by the ever present charring effect, which takes palce at the edges of the cut pieces. To minimise this aspect positive and negative pieces have to be cut under stringent focusing conditions and with slight different scales. The condittions for our machine are presented.

  5. A Multi-scale Approach for CO2 Accounting and Risk Analysis in CO2 Enhanced Oil Recovery Sites

    Science.gov (United States)

    Dai, Z.; Viswanathan, H. S.; Middleton, R. S.; Pan, F.; Ampomah, W.; Yang, C.; Jia, W.; Lee, S. Y.; McPherson, B. J. O. L.; Grigg, R.; White, M. D.

    2015-12-01

    Using carbon dioxide in enhanced oil recovery (CO2-EOR) is a promising technology for emissions management because CO2-EOR can dramatically reduce carbon sequestration costs in the absence of greenhouse gas emissions policies that include incentives for carbon capture and storage. This study develops a multi-scale approach to perform CO2 accounting and risk analysis for understanding CO2 storage potential within an EOR environment at the Farnsworth Unit of the Anadarko Basin in northern Texas. A set of geostatistical-based Monte Carlo simulations of CO2-oil-water flow and transport in the Marrow formation are conducted for global sensitivity and statistical analysis of the major risk metrics: CO2 injection rate, CO2 first breakthrough time, CO2 production rate, cumulative net CO2 storage, cumulative oil and CH4 production, and water injection and production rates. A global sensitivity analysis indicates that reservoir permeability, porosity, and thickness are the major intrinsic reservoir parameters that control net CO2 injection/storage and oil/CH4 recovery rates. The well spacing (the distance between the injection and production wells) and the sequence of alternating CO2 and water injection are the major operational parameters for designing an effective five-spot CO2-EOR pattern. The response surface analysis shows that net CO2 injection rate increases with the increasing reservoir thickness, permeability, and porosity. The oil/CH4 production rates are positively correlated to reservoir permeability, porosity and thickness, but negatively correlated to the initial water saturation. The mean and confidence intervals are estimated for quantifying the uncertainty ranges of the risk metrics. The results from this study provide useful insights for understanding the CO2 storage potential and the corresponding risks of commercial-scale CO2-EOR fields.

  6. Interpenetrating Metal-Metalloporphyrin Framework for Selective CO2 Uptake and Chemical Transformation of CO2.

    Science.gov (United States)

    Gao, Wen-Yang; Tsai, Chen-Yen; Wojtas, Lukasz; Thiounn, Timmy; Lin, Chu-Chieh; Ma, Shengqian

    2016-08-01

    Herein we report a robust primitive cubic (pcu)-topology metal-metalloporphyrin framework (MMPF), MMPF-18, which was constructed from a ubiquitous secondary building unit of a tetranuclear zinc cluster, Zn4(μ4-O)(-COO)6, and a linear organic linker of 5,15-bis(4-carboxyphenyl)porphyrin (H2bcpp). The strong π-π stacking from porphyrins and the lengthy H2bcpp ligand affords a 4-fold-interpenetrating network along with reduced void spaces and confined narrow channels. Thereby, MMPF-18 presents segmented pores and high-density metalloporphyrin centers for selective CO2 uptake over CH4 and size-selective chemical transformation of CO2 with epoxides forming cyclic carbonates under ambient conditions. PMID:27337152

  7. Ozone Radiative Feedback in Global Warming Simulations with CO2 and non-CO2 Forcings

    Science.gov (United States)

    Ponater, M.; Rieger, V.; Dietmüller, S.

    2015-12-01

    It has been found that ozone radiative feedback acts to reduce the climate sensitivity in global warming simulations including interactive atmospheric chemistry, if the radiative forcing origins from CO2 increase. The effect can be traced to a negative feedback from stratospheric ozone changes and it is amplified by a reduced positive feedback from stratospheric water vapor.These findings cannot be simply transferred to simulations in which the warming is driven by a non-CO2 radiative forcing. Using a perturbation of surface NOx and CO emissions as an example, we demonstrate that a tropospheric ozone feedback may have significant impacts on physical feedbacks. These interactions can act to an extent that the effect of a negative ozone feedback can be reversed by changes in other feedbacks, thus increasing the climate sensitivity instead of reducing it. We also address some conceptual issues showing up as chemical feedbacks are added to set of physical feedbacks in simulation with interactive chemistry.

  8. Ozone radiative feedback in global warming simulations with CO2 and non-CO2 forcing

    OpenAIRE

    Dietmüller, Simone; Ponater, Michael; Rieger, Vanessa

    2016-01-01

    It has been found that ozone radiative feedback acts to reduce the climate sensitivity in global warming simulations including interactive atmospheric chemistry, if the radiative forcing origins from CO2 increase. The main reason for this is a dynamically induced ozone reduction in the lowermost tropical stratosphere (negative ozone radiative feedback). The climate sensitivity reduction is amplified by a less positive stratospheric water vapour feedback in comparison with a respective simulat...

  9. Opportunities for CO2 Reductions and CO2-Lean Energy Systems in Pulp and Paper Mills

    OpenAIRE

    Möllersten, Kenneth

    2002-01-01

    The risk for climate change is a growing concern for theglobal society. According to what is known as the Kyoto Protocol,developed countries have committed themselves to reduce theirgreenhouse gas (GHG) emissions. The purpose of this thesis hasbeen to analyse opportunities for CO2 reductions in Swedish pulpand paper mills. The pulp and paper industry accounts forsignificant shares of the Swedish utilisationof both electricityand, in particular, biomass fuels. In this thesis, it has been agoal...

  10. Improved Efficiency of Miscible CO2 Floods and Enhanced Prospects for CO2 Flooding Heterogeneous Reservoirs

    Energy Technology Data Exchange (ETDEWEB)

    Grigg, Reid B.; Schechter, David S.

    1999-10-15

    The goal of this project is to improve the efficiency of miscible CO2 floods and enhance the prospects for flooding heterogeneous reservoirs. This report provides results of the second year of the three-year project that will be exploring three principles: (1) Fluid and matrix interactions (understanding the problems). (2) Conformance control/sweep efficiency (solving the problems. 3) Reservoir simulation for improved oil recovery (predicting results).

  11. Characterization of Activated Carbons from Oil-Palm Shell by CO2 Activation with No Holding Carbonization Temperature

    OpenAIRE

    S. G. Herawan; Hadi, M. S.; Md. R. Ayob; A. Putra

    2013-01-01

    Activated carbons can be produced from different precursors, including coals of different ranks, and lignocellulosic materials, by physical or chemical activation processes. The objective of this paper is to characterize oil-palm shells, as a biomass byproduct from palm-oil mills which were converted into activated carbons by nitrogen pyrolysis followed by CO2 activation. The effects of no holding peak pyrolysis temperature on the physical characteristics of the activated carbons are studied....

  12. pCO2 in Sea Water and its Effect on the Movement of CO2 in Nature

    OpenAIRE

    Kanwisher, John

    2011-01-01

    A method is described for measuring pCO2 in sea water. A gas phase is analyzed continuously by infrared absorption for CO2 while it is equilibrated gently with the water in a countercurrent column. It has been used to determine the changes in pCO2 produced by variations of temperature and total CO2. Partial pressure shows large changes for small increments in these two independant variables. These properties of sea water are useful in estimating the movement of CO2 between the atmosphere and ...

  13. Interpreting plant-sampled ¿14CO2 to study regional anthropogenic CO2 signals in Europe

    OpenAIRE

    Bozhinova, D.N.

    2015-01-01

    "Interpreting plant-sampled Δ14CO2 to study regional anthropogenic CO2 signals in Europe" Author:  Denica Bozhinova This thesis investigates the quantitative interpretation of plant-sampled ∆14CO2 as an indicator of fossil fuel CO2 recently added to the atmosphere. We present a methodology to calculate the ∆14CO2 that has accumulated in a plant over its growing period, based on a modeling framework consisting of a plant growth model (SUCROS) and an atmospheric transport m...

  14. Equipment for simultaneous measurement of 14CO2, 12CO2 and water vapour in plant gas exchange studies

    International Nuclear Information System (INIS)

    The development of a scintillation system for low 14CO2 radioactivity measurements is described and its use in determining parameters of gas exchange in plants is outlined. It permits simultaneous measurement of true photosynthesis (14CO2 absorption) and apparent photosynthesis (12CO2 absorption) and hence determination of photorespiration in light. In darkness it permits simultaneous measurement of respiration (12CO2 evolution) and dark carboxylation (14CO2 absorption). Transpiration of plants can also be measured in both light and darkness. The course of gas exchange in wheat and maize plants is shown. (Auth./C.F.)

  15. CO2 reforming of methane: valorizing CO2 by means of Dielectric Barrier Discharge

    International Nuclear Information System (INIS)

    The impact of pollution on the environment is causing several problems that are to be reduced as much as possible. One important example is the production of CO2 that is emitted by many transport and industrial applications. An interesting solution is to view CO2 as a source instead of a product that can be stocked. The case considered in this work is the CO2 reformation of methane producing hydrogen and CO. It is an endothermic reaction, for which the activition barrier needs to be overcome. The method of Dielectric Barrier Discharge can do this efficiently. The process relies on the collision of electrons, which are accelerated under an electrical field that is created in the discharge area. This leads to the formation of reactive species, which facilitate the abovementioned reaction. The determination of the electron density is performed by PLASIMO. The study is subsequently continued using the Reaction Engineering module in COMSOL (with an incorporated kinetic mechanism) in order to model the discharge phase. Then COMSOL (continuity and Navier-Stokes equations) is used to model the flow in the post-discharge phase. The results showed that both a 2D and 3D model can be used to model the chemical-plasma process. These methods need strongly reduced kinetic mechanism, which in some cases can cause loss of precision. It is also observed that the present experimental set-up that is modeled needs to be improved. A suggestion is made.

  16. Ranking nodes in growing networks: When PageRank fails

    CERN Document Server

    Mariani, Manuel Sebastian; Zhang, Yi-Cheng

    2015-01-01

    PageRank is arguably the most popular ranking algorithm which is being applied in real systems ranging from information to biological and infrastructure networks. Despite its outstanding popularity and broad use in different areas of science, the relation between the algorithm's efficacy and properties of the network on which it acts has not yet been fully understood. We study here PageRank's performance on a network model supported by real data, and show that realistic temporal effects make PageRank fail in individuating the most valuable nodes for a broad range of model parameters. Results on real data are in qualitative agreement with our model-based findings. This failure of PageRank reveals that the static approach to information filtering is inappropriate for a broad class of growing systems, and suggest that time-dependent algorithms that are based on the temporal linking patterns of these systems are needed to better rank the nodes.

  17. Photorespiration in Air and High CO(2)-Grown Chlorella pyrenoidosa.

    Science.gov (United States)

    Shelp, B J; Canvin, D T

    1981-12-01

    Oxygen inhibition of photosynthesis and CO(2) evolution during photorespiration were compared in high CO(2)-grown and air-grown Chlorella pyrenoidosa, using the artificial leaf technique at pH 5.0. High CO(2) cells, in contrast to air-grown cells, exhibited a marked inhibition of photosynthesis by O(2), which appeared to be competitive and similar in magnitude to that in higher C(3) plants. With increasing time after transfer to air, the photosynthetic rate in high CO(2) cells increased while the O(2) effect declined. Photorespiration, measured as the difference between (14)CO(2) and (12)CO(2) uptake, was much greater and sensitive to O(2) in high CO(2) cells. Some CO(2) evolution was also present in air-grown algae; however, it did not appear to be sensitive to O(2). True photosynthesis was not affected by O(2) in either case. The data indicate that the difference between high CO(2) and air-grown algae could be attributed to the magnitude of CO(2) evolution. This conclusion is discussed with reference to the oxygenase reaction and the control of photorespiration in algae. PMID:16662134

  18. Polyurethane Foam-Based Ultramicroporous Carbons for CO2 Capture.

    Science.gov (United States)

    Ge, Chao; Song, Jian; Qin, Zhangfeng; Wang, Jianguo; Fan, Weibin

    2016-07-27

    A series of sustainable porous carbon materials were prepared from waste polyurethane foam and investigated for capture of CO2. The effects of preparation conditions, such as precarbonization, KOH to carbon precursor weight ratio, and activation temperature, on the porous structure and CO2 adsorption properties were studied for the purpose of controlling pore sizes and nitrogen content and developing high-performance materials for capture of CO2. The sample prepared at optimum conditions shows CO2 adsorption capacities of 6.67 and 4.33 mmol·g(-1) at 0 and 25 °C under 1 bar, respectively, which are comparable to those of the best reported porous carbons prepared from waste materials. The HCl treatment experiment reveals that about 80% of CO2 adsorption capacity arises from physical adsorption, while the other 20% is due to the chemical adsorption originated from the interaction of basic N groups and CO2 molecules. The relationship between CO2 uptake and pore size at different temperatures indicates that the micropores with pore size smaller than 0.86 and 0.70 nm play a dominant role in the CO2 adsorption at 0 and 25 °C, respectively. It was found that the obtained carbon materials exhibited high recyclability and high selectivity to adsorption of CO2 from the CO2 and N2 mixture. PMID:27376177

  19. Bubble nucleation in polymer–CO2 mixtures.

    Science.gov (United States)

    Xu, Xiaofei; Cristancho, Diego E; Costeux, Stéphane; Wang, Zhen-Gang

    2013-10-28

    We combine density-functional theory with the string method to calculate the minimum free energy path of bubble nucleation in two polymer–CO2 mixture systems, poly(methyl methacrylate) (PMMA)–CO2 and polystyrene (PS)–CO2. Nucleation is initiated by saturating the polymer liquid with high pressure CO2 and subsequently reducing the pressure to ambient condition. Below a critical temperature (Tc), we find that there is a discontinuous drop in the nucleation barrier as a function of increased initial CO2 pressure (P0), as a result of an underlying metastable transition from a CO2-rich-vapor phase to a CO2-rich-liquid phase. The nucleation barrier is generally higher for PS–CO2 than for PMMA–CO2 under the same temperature and pressure conditions, and both higher temperature and higher initial pressure are required to lower the nucleation barrier for PS–CO2 to experimentally relevant ranges. Classical nucleation theory completely fails to capture the structural features of the bubble nucleus and severely underestimates the nucleation barrier. PMID:26029777

  20. Buoyant dispersal of CO2 during geological storage

    Science.gov (United States)

    Hesse, M. A.; Woods, A. W.

    2010-01-01

    Carbon capture and storage is currently the only technology that may allow significant reductions in CO2 emissions from large point sources. Seismic images of geological CO2 storage show the rise of CO2 is influenced by horizontal shales. The buoyant CO2 spreads beneath impermeable barriers until a gap allows its upward migration. The large number and small scale of these barriers makes the prediction of the CO2 migration path and hence the magnitude of CO2 trapping very challenging. We show that steady buoyancy dominated flows in complex geometries can be modeled as a cascade of flux partitioning events. This approach allows the analysis of two-dimensional plume dispersal from a horizontal injection well. We show that the plume spreads laterally with height y above the source according to (y/h)1/2 L, where L is the width of the shales and h is their vertical separation. The fluid volume below successive shale layers, and therefore the magnitude of trapped CO2, increase as (y/h)5/4 above the source, so that every additional layer of barriers traps more CO2 than the one below. Upscaling small scale flow barriers by reducing the vertical permeability, common in numerical simulations of CO2 storage, does not capture the dispersion and trapping of the CO2 plume by the flow barriers.

  1. Sequestering CO2 in the Built Environment

    Science.gov (United States)

    Constantz, B. R.

    2009-12-01

    Calera’s Carbonate Mineralization by Aqueous Precipitation (CMAP) technology with beneficial reuse has been called, “game-changing” by Carl Pope, Director of the Sierra Club. Calera offers a solution to the scale of the carbon problem. By capturing carbon into the built environment through carbonate mineralization, Calera provides a sound and cost-effective alternative to Geologic Sequestration and Terrestrial Sequestration. The CMAP technology permanently converts carbon dioxide into a mineral form that can be stored above ground, or used as a building material. The process produces a suite of carbonate-containing minerals of various polymorphic forms. Calera product can be substituted into blends with ordinary Portland cements and used as aggregate to produce concrete with reduced carbon, carbon neutral, or carbon negative footprints. For each ton of product produced, approximately half a ton of carbon dioxide can be sequestered using the Calera process. Coal and natural gas are composed of predominately istopically light carbon, as the carbon in the fuel is plant-derived. Thus, power plant CO2 emissions have relatively low δ13C values.The carbon species throughout the CMAP process are identified through measuring the inorganic carbon content, δ13C values of the dissolved carbonate species, and the product carbonate minerals. Measuring δ13C allows for tracking the flue gas CO2 throughout the capture process. Initial analysis of the capture of propane flue gas (δ13C ˜ -25 ‰) with seawater (δ13C ˜ -10 ‰) and industrial brucite tailings from a retired magnesium oxide plant in Moss Landing, CA (δ13C ˜ -7 ‰ from residual calcite) produced carbonate mineral products with a δ13C value of ˜ -20 ‰. This isotopically light carbon, transformed from flue gas to stable carbonate minerals, can be transferred and tracked through the capture process, and finally to the built environment. CMAP provides an economical solution to global warming by producing

  2. Total (fumarolic + diffuse soil) CO2 output from Furnas volcano

    Science.gov (United States)

    Pedone, M.; Viveiros, F.; Aiuppa, A.; Giudice, G.; Grassa, F.; Gagliano, A. L.; Francofonte, V.; Ferreira, T.

    2015-10-01

    Furnas volcano, in São Miguel island (Azores), being the surface expression of rising hydrothermal steam, is the site of intense carbon dioxide (CO2) release by diffuse degassing and fumaroles. While the diffusive CO2 output has long (since the early 1990s) been characterized by soil CO2 surveys, no information is presently available on the fumarolic CO2 output. Here, we performed (in August 2014) a study in which soil CO2 degassing survey was combined for the first time with the measurement of the fumarolic CO2 flux. The results were achieved by using a GasFinder 2.0 tunable diode laser. Our measurements were performed in two degassing sites at Furnas volcano (Furnas Lake and Furnas Village), with the aim of quantifying the total (fumarolic + soil diffuse) CO2 output. We show that, within the main degassing (fumarolic) areas, the soil CO2 flux contribution (9.2 t day-1) represents a minor (~15 %) fraction of the total CO2 output (59 t day-1), which is dominated by the fumaroles (~50 t day-1). The same fumaroles contribute to ~0.25 t day-1 of H2S, based on a fumarole CO2/H2S ratio of 150 to 353 (measured with a portable Multi-GAS). However, we also find that the soil CO2 contribution from a more distal wider degassing structure dominates the total Furnas volcano CO2 budget, which we evaluate (summing up the CO2 flux contributions for degassing soils, fumarolic emissions and springs) at ~1030 t day-1.

  3. Understanding urban atmospheric CO2: Challenges and Opportunities

    Science.gov (United States)

    Pataki, D. E.; Ehleringer, J. R.; Forster, C. B.; Klewicki, J. C.; Pardyjak, E. R.; Peterson, R. E.; Steenburgh, W. J.; Tyler, B. J.

    2004-12-01

    Many studies have shown that atmospheric CO2 concentrations are elevated far above ambient levels in cities due to strong local sources. Measurements of urban atmospheric CO2 mixing ratio, its isotopic composition, and its sources and sinks provide opportunities to understand the local carbon cycle and biogeochemistry of cities, which is increasingly important in studies of regional and global change as well as urban sustainability and planning. In an ongoing project in the Salt Lake Valley, Utah, measurements of CO2 mixing ratio and the isotopic composition of CO2 have shown that vehicle exhaust significantly elevates CO2 mixing ratios above ambient, particularly in the wintertime when temperature inversions create stable conditions. Natural gas combustion also makes a large contribution to CO2 mixing ratio in the winter, but becomes negligible in the summer. However, the urban "forest" in the Salt Lake Valley plays an active role in influencing CO2 mixing ratio during the spring, summer, and fall through photosynthesis and respiration. Atmospheric CO2 measurements in the Salt Lake Valley are also useful in that they correlate with air pollutants such as aerosols, particularly in the wintertime when CO2 sources are dominated by combustion. The relationship between CO2 mixing ratio and other pollutants varies as a function of fuel source (natural gas versus gasoline) and meteorological variables that affect atmospheric chemistry of reactive compounds; therefore, these relationships provide additional information about sources and sinks for atmospheric constituents. Finally, CO2 is a stable atmospheric tracer in that it does not undergo chemical transformations in the atmosphere. Measurements in the Salt Lake Valley showed that the temporal and spatial distribution of CO2 in the wintertime may provide information about atmospheric transport during complex cold pools events if mixing ratios are monitored at multiple locations. These results suggest that studies of

  4. Economic evaluation of CO2 pipeline transport in China

    International Nuclear Information System (INIS)

    Highlights: ► We build a static hydrodynamic model of CO2 pipeline for CCS application. ► We study the impact on pressure drop of pipeline by viscosity, density and elevation. ► We point out that density has a bigger impact on pressure drop than viscosity. ► We suggest dense phase transport is preferred than supercritical state. ► We present cost-optimal pipeline diameters for different flowrates and distances. - Abstract: Carbon capture and sequestration (CCS) is an important option for CO2 mitigation and an optimized CO2 pipeline transport system is necessary for large scale CCS implementation. In the present work, a hydrodynamic model for CO2 pipeline transport was built up and the hydrodynamic performances of CO2 pipeline as well as the impacts of multiple factors on pressure drop behavior along the pipeline were studied. Based on the model, an economic model was established to optimize the CO2 pipeline transport system economically and to evaluate the unit transport cost of CO2 pipeline in China. The hydrodynamic model results show that pipe diameter, soil temperature, and pipeline elevation change have significant influence on the pressure drop behavior of CO2 in the pipeline. The design of pipeline system, including pipeline diameter and number of boosters etc., was optimized to achieve a lowest unit CO2 transport cost. In regarding to the unit cost, when the transport flow rate and distance are between 1–5 MtCO2/year and 100–500 km, respectively, the unit CO2 transport cost mainly lies between 0.1–0.6 RMB/(tCO2 km) and electricity consumption cost of the pipeline inlet compressor was found to take more than 60% of the total cost. The present work provides reference for CO2 transport pipeline design and for feasibility evaluation of potential CCS projects in China.

  5. Model quantification of the CO2 storage in the Los Páramos site (Duero basin, NE Spain)

    Science.gov (United States)

    Nardi, Albert; Grandia, Fidel; Abarca, Elena; Motis, Kilian; Molinero, Jorge

    2013-04-01

    The Duero basin in NW Spain is one the most promising basin for CO2 storage in the Iberian Peninsula due to the existence of favourable deep aquifers close to large CO2 emission point sources. A number of projects are presently active either for scientific research (e.g., the Hontomín site, OXI-CFB300 EPRR project) or commercial purposes (e.g., Sahagún and Los Páramos projects). The project called Los Páramos intends to assess the injection of CO2 in a group of dome-shaped structures with an estimated total capacity of 200 Mt (ranked 2nd in the Iberian Peninsula, IGME 2010). These domes were studied in the past for hydrocarbon exploration and a large body of information is available from seismic profiles (over 170 km) and 3 deep wells. The Los Páramos site is emplaced in the San Pedro Folded Band (SPFB) that consists mainly of thick-skinned thrusts of Mesozoic rocks (Triassic and Upper Cretaceous) sealed by a thick (1200-1500 m), undeformed cover of Tertiary claystones. Dome-like structures are related to thrusts leading to favourable reservoirs. The target horizon for CO2 storage is the Utrillas Fm sandstone with high porosity (13-20%) and thickness (225-250 m). In three of the domes, the Utrillas Fm is below -800m, allowing thus the storage of CO2(sc). This sandstone hosts an aquifer containing saline water, up to 50 g·L-1, according to the data from drill wells. The presence of saline groundwater is explained by water interaction with Triassic evaporite layers just underlying the Utrillas Fm sandstones. The CO2 storage at Los Paramos site is planned via injection of supercritical CO2 (CO2(sc)) in the Utrillas Fm. In general, the next four trapping mechanisms are expected, which are of increasing importance through time (1) structural, (2) residual saturation, (3) dissolution, and (4) mineral. The prediction of the mass of CO2 stored through time in any storage systems is an essential parameter in the pre-injection assessment of a geological storage. For

  6. Using ground and intact coal Samples to evaluate hydrocarbon fate during supercritical CO2 injection into coal beds: effects of particle size and coal moisture

    Science.gov (United States)

    Kolak, Jon; Hackley, Paul C.; Ruppert, Leslie F.; Warwick, Peter D.; Burruss, Robert

    2015-01-01

    To investigate the potential for mobilizing organic compounds from coal beds during geologic carbon dioxide (CO2) storage (sequestration), a series of solvent extractions using dichloromethane (DCM) and using supercritical CO2 (40 °C and 10 MPa) were conducted on a set of coal samples collected from Louisiana and Ohio. The coal samples studied range in rank from lignite A to high volatile A bituminous, and were characterized using proximate, ultimate, organic petrography, and sorption isotherm analyses. Sorption isotherm analyses of gaseous CO2 and methane show a general increase in gas storage capacity with coal rank, consistent with findings from previous studies. In the solvent extractions, both dry, ground coal samples and moist, intact core plug samples were used to evaluate effects of variations in particle size and moisture content. Samples were spiked with perdeuterated surrogate compounds prior to extraction, and extracts were analyzed via gas chromatography–mass spectrometry. The DCM extracts generally contained the highest concentrations of organic compounds, indicating the existence of additional hydrocarbons within the coal matrix that were not mobilized during supercritical CO2 extractions. Concentrations of aliphatic and aromatic compounds measured in supercritical CO2 extracts of core plug samples generally are lower than concentrations in corresponding extracts of dry, ground coal samples, due to differences in particle size and moisture content. Changes in the amount of extracted compounds and in surrogate recovery measured during consecutive supercritical CO2extractions of core plug samples appear to reflect the transition from a water-wet to a CO2-wet system. Changes in coal core plug mass during supercritical CO2 extraction range from 3.4% to 14%, indicating that a substantial portion of coal moisture is retained in the low-rank coal samples. Moisture retention within core plug samples, especially in low-rank coals, appears to inhibit

  7. Rankings, creatividad y urbanismo

    Directory of Open Access Journals (Sweden)

    JOAQUÍN SABATÉ

    2008-08-01

    Full Text Available La competencia entre ciudades constituye uno de los factores impulsores de procesos de renovación urbana y los rankings han devenido instrumentos de medida de la calidad de las ciudades. Nos detendremos en el caso de un antiguo barrio industrial hoy en vías de transformación en distrito "creativo" por medio de una intervención urbanística de gran escala. Su análisis nos descubre tres claves críticas. En primer lugar, nos obliga a plantearnos la definición de innovación urbana y cómo se integran el pasado, la identidad y la memoria en la construcción del futuro. Nos lleva a comprender que la innovación y el conocimiento no se "dan" casualmente, sino que son el fruto de una larga y compleja red en la que participan saberes, espacios, actores e instituciones diversas en naturaleza, escala y magnitud. Por último nos obliga a reflexionar sobre el valor que se le otorga a lo local en los procesos de renovación urbana.Competition among cities constitutes one ofthe main factors o furban renewal, and rankings have become instruments to indícate cities quality. Studying the transformation of an old industrial quarter into a "creative district" by the means ofa large scale urban project we highlight three main conclusions. First, itasks us to reconsider the notion ofurban innovation and hoto past, identity and memory should intégrate the future development. Second, it shows that innovation and knowledge doesn't yield per chance, but are the result ofa large and complex grid of diverse knowledges, spaces, agents and institutions. Finally itforces us to reflect about the valué attributed to the "local" in urban renewalprocesses.

  8. Wikipedia ranking of world universities

    Science.gov (United States)

    Lages, José; Patt, Antoine; Shepelyansky, Dima L.

    2016-03-01

    We use the directed networks between articles of 24 Wikipedia language editions for producing the wikipedia ranking of world Universities (WRWU) using PageRank, 2DRank and CheiRank algorithms. This approach allows to incorporate various cultural views on world universities using the mathematical statistical analysis independent of cultural preferences. The Wikipedia ranking of top 100 universities provides about 60% overlap with the Shanghai university ranking demonstrating the reliable features of this approach. At the same time WRWU incorporates all knowledge accumulated at 24 Wikipedia editions giving stronger highlights for historically important universities leading to a different estimation of efficiency of world countries in university education. The historical development of university ranking is analyzed during ten centuries of their history.

  9. Low-rank coal research

    Energy Technology Data Exchange (ETDEWEB)

    Weber, G. F.; Laudal, D. L.

    1989-01-01

    This work is a compilation of reports on ongoing research at the University of North Dakota. Topics include: Control Technology and Coal Preparation Research (SO{sub x}/NO{sub x} control, waste management), Advanced Research and Technology Development (turbine combustion phenomena, combustion inorganic transformation, coal/char reactivity, liquefaction reactivity of low-rank coals, gasification ash and slag characterization, fine particulate emissions), Combustion Research (fluidized bed combustion, beneficiation of low-rank coals, combustion characterization of low-rank coal fuels, diesel utilization of low-rank coals), Liquefaction Research (low-rank coal direct liquefaction), and Gasification Research (hydrogen production from low-rank coals, advanced wastewater treatment, mild gasification, color and residual COD removal from Synfuel wastewaters, Great Plains Gasification Plant, gasifier optimization).

  10. Biofiksasi CO2 Oleh Mikroalga Chlamydomonas sp dalam Photobioreaktor Tubular

    Directory of Open Access Journals (Sweden)

    Hadiyanto Hadiyanto

    2014-05-01

    Full Text Available Mikroalga memiliki potensi dalam membiofiksasi CO2 dan dapat dimanfaatkan untuk mengurangi kadar CO2 dalam gas pencemar. Pertumbuhan mikroalga sangat dipengaruhi oleh konsentrasi gas CO2 di dalam gas pencemar. Tujuan penelitian ini adalah untuk mengeetahui kemampuan mikroalga Chlamydomonas sp yang dikultivasi dalam photobioreaktor tubular dalam penyerapan gas CO2 serta untuk mengetahui konsentrasi maksimum gas CO2 dalam umpan untuk memproduksi biomasa mikroalga yang optimal. Percobaan dilakukan dnegan memvariasi laju alir dari 0.03 -0.071 L/menit dan konsentrasi CO2 dalam umpan 10-30%. Hasil penelitian menunjukkan bahwa biomasa mikroalga dapat diproduksi dengan maksimal dengan konsentrasi gas CO2 20% dengan laju alir 0.07 L/min. Semakin tinggi laju alir maka produksi biomasa alga semakin besar. Kecepatan pertumbuhan alga maksimum terjadi pada 0.31 /hari. Pada konsentrasi gas CO2 30%, terjadi substrate inhibition yang disebabkan carbon dalam bentuk ion bicarbonate tidak dapat dikonsumsi lagi di dalam kultur alga. Kata kunci : Mikroalga, chlamydomonas sp, biofiksasi CO2, biogas Abstract Microalgae have a potential for CO2 biofixation and therefore can be used to reduce the CO2 concentration in the gas pollutants. Moreover, microalgae growth is strongly affected by the concentration of CO2 in the exhaust gas pollutants. The objective of this research was to investigate the ability of microalgae Chlamydomonas sp which was cultivated in a tubular photobioreactor for CO2 absorption as well as to determine the maximum concentration of CO2 in the feed gas to obtain optimum microalgae biomass. The experiments were performed by varying the gas flow rate of 0.03 -0.071 L / min and the concentration of CO2 in the feed of 10-30%. The results showed that the maximum biomass of microalgae can be produced with CO2 concentration of 20% vol with a flow rate of 0.07 L / min. The result also showed that increasing the gas flow rate, the greater of the production of

  11. A 40-million-year history of atmospheric CO(2).

    Science.gov (United States)

    Zhang, Yi Ge; Pagani, Mark; Liu, Zhonghui; Bohaty, Steven M; Deconto, Robert

    2013-10-28

    The alkenone-pCO2 methodology has been used to reconstruct the partial pressure of ancient atmospheric carbon dioxide (pCO2) for the past 45 million years of Earth's history (Middle Eocene to Pleistocene epochs). The present long-term CO2 record is a composite of data from multiple ocean localities that express a wide range of oceanographic and algal growth conditions that potentially bias CO2 results. In this study, we present a pCO2 record spanning the past 40 million years from a single marine locality, Ocean Drilling Program Site 925 located in the western equatorial Atlantic Ocean. The trends and absolute values of our new CO2 record site are broadly consistent with previously published multi-site alkenone-CO2 results. However, new pCO2 estimates for the Middle Miocene are notably higher than published records, with average pCO2 concentrations in the range of 400-500 ppm. Our results are generally consistent with recent pCO2 estimates based on boron isotope-pH data and stomatal index records, and suggest that CO2 levels were highest during a period of global warmth associated with the Middle Miocene Climatic Optimum (17-14 million years ago, Ma), followed by a decline in CO2 during the Middle Miocene Climate Transition (approx. 14 Ma). Several relationships remain contrary to expectations. For example, benthic foraminiferal δ(18)O records suggest a period of deglaciation and/or high-latitude warming during the latest Oligocene (27-23 Ma) that, based on our results, occurred concurrently with a long-term decrease in CO2 levels. Additionally, a large positive δ(18)O excursion near the Oligocene-Miocene boundary (the Mi-1 event, approx. 23 Ma), assumed to represent a period of glacial advance and retreat on Antarctica, is difficult to explain by our CO2 record alone given what is known of Antarctic ice sheet history and the strong hysteresis of the East Antarctic Ice Sheet once it has grown to continental dimensions. We also demonstrate that in the

  12. Tectonic impact on the dynamics of CO2-rich fluid migration in Utah

    Science.gov (United States)

    Nadine, E. Z.; Jean Luc, F.; Remy, D.; Battani, A.; Olivier, V.

    2009-12-01

    With the objective to rank the first order parameters acting in the long term CO2 storage, IFP is developing an integrated study based on the analytical results around the natural silici-clastic analogue of the Colorado Plateau in Utah. What are the dominant parameters which governed the fluid/gas migration in front of the Sevier fold-and-thrust Belt, particularly the CO2-enriched ones? Several sites have been investigated in Utah and Idaho provinces; in the Colorado Plateau, East and in front of the Sevier fold-and-thrust belt, as well as in the Basin & Range geological province North and South West of Salt Lake city (Sevier basin). As a first site selection, three distinct structural provinces have been analysed depending on their seal/reservoir characteristics for confinement: the Green River leaking area (Utah), where large WNW-ESE faults (Salt Wash, Little Wash F...) show several water, oil and gas (CO2, HC) seepages; the Basin & Range province (Utah & Idaho provinces) where low-angle normal faults are seismically active (leaking locally); and the Canyonlands zone (Utah), south of the Moab fault, where the system is well confined. The migration pathways used by composite gas and particularly CO2-enriched fluids (in the Green River area) combined with a reducing agent are locally easily recognisable by the bleaching effect where some reservoir levels or the faults pathways have been flushed. The architecture of the paleo and active fluid migration network can thus be mapped. As a second selective ranking, natural gas have been sampled either from oil/gas producing wells in the Moab area and Ferron Valley, or from natural seepages along leaking fault sections or from geysers along the Green-River fault system. The results, based on noble gas isotope analyses (Battani et al, AGU fall meeting 2009) show that 3 distinct provinces can be "isolated", either marked by the occurrence of mantle-derived CO2, or mixed mantle/crustal CO2 signature of varying ratio. How to

  13. Poverty Rankings of Opportunity Profiles

    OpenAIRE

    Vito Peragine; Ernesto Savaglio; Stefano Vannucci

    2008-01-01

    We address the problem of ranking distributions of opportunity sets in terms of poverty. In order to accomplish this task, we identify a suitable notion of ‘multidimensional poverty line’ and we characterize axiomatically several poverty rankings of opportunity profiles. Among them, the Head-Count and the Opportunity-Gap poverty rankings, which are the natural counterparts of the most widely used income poverty indices.

  14. CO2 Storage related Groundwater Impacts and Protection

    Science.gov (United States)

    Fischer, Sebastian; Knopf, Stefan; May, Franz; Rebscher, Dorothee

    2016-03-01

    Injection of CO2 into the deep subsurface will affect physical and chemical conditions in the storage environment. Hence, geological CO2 storage can have potential impacts on groundwater resources. Shallow freshwater can only be affected if leakage pathways facilitate the ascent of CO2 or saline formation water. Leakage associated with CO2 storage cannot be excluded, but potential environmental impacts could be reduced by selecting suitable storage locations. In the framework of risk assessment, testing of models and scenarios against operational data has to be performed repeatedly in order to predict the long-term fate of CO2. Monitoring of a storage site should reveal any deviations from expected storage performance, so that corrective measures can be taken. Comprehensive R & D activities and experience from several storage projects will enhance the state of knowledge on geological CO2 storage, thus enabling safe storage operations at well-characterised and carefully selected storage sites while meeting the requirements of groundwater protection.

  15. Uncertainty quantification for CO2 sequestration and enhanced oil recovery

    CERN Document Server

    Dai, Zhenxue; Fessenden-Rahn, Julianna; Middleton, Richard; Pan, Feng; Jia, Wei; Lee, Si-Yong; McPherson, Brian; Ampomah, William; Grigg, Reid

    2014-01-01

    This study develops a statistical method to perform uncertainty quantification for understanding CO2 storage potential within an enhanced oil recovery (EOR) environment at the Farnsworth Unit of the Anadarko Basin in northern Texas. A set of geostatistical-based Monte Carlo simulations of CO2-oil-water flow and reactive transport in the Morrow formation are conducted for global sensitivity and statistical analysis of the major uncertainty metrics: net CO2 injection, cumulative oil production, cumulative gas (CH4) production, and net water injection. A global sensitivity and response surface analysis indicates that reservoir permeability, porosity, and thickness are the major intrinsic reservoir parameters that control net CO2 injection/storage and oil/gas recovery rates. The well spacing and the initial water saturation also have large impact on the oil/gas recovery rates. Further, this study has revealed key insights into the potential behavior and the operational parameters of CO2 sequestration at CO2-EOR s...

  16. A Circular Bioeconomy with Biobased Products from CO2 Sequestration.

    Science.gov (United States)

    Venkata Mohan, S; Modestra, J Annie; Amulya, K; Butti, Sai Kishore; Velvizhi, G

    2016-06-01

    The unprecedented climate change influenced by elevated concentrations of CO2 has compelled the research world to focus on CO2 sequestration. Although existing natural and anthropogenic CO2 sinks have proven valuable, their ability to further assimilate CO2 is now questioned. Thus, we highlight here the importance of biological sequestration methods as alternate and viable routes for mitigating climate change while simultaneously synthesizing value-added products that could sustainably fuel the circular bioeconomy. Four conceptual models for CO2 biosequestration and the synthesis of biobased products, as well as an integrated CO2 biorefinery model, are proposed. Optimizing and implementing this biorefinery model might overcome the limitations of existing sequestration methods and could help realign the carbon balance. PMID:27048926

  17. Rechargeable Room-Temperature Na-CO2 Batteries.

    Science.gov (United States)

    Hu, Xiaofei; Sun, Jianchao; Li, Zifan; Zhao, Qing; Chen, Chengcheng; Chen, Jun

    2016-05-23

    Developing rechargeable Na-CO2 batteries is significant for energy conversion and utilization of CO2 . However, the reported batteries in pure CO2 atmosphere are non-rechargeable with limited discharge capacity of 200 mAh g(-1) . Herein, we realized the rechargeability of a Na-CO2 battery, with the proposed and demonstrated reversible reaction of 3 CO2 +4 Na↔2 Na2 CO3 +C. The battery consists of a Na anode, an ether-based electrolyte, and a designed cathode with electrolyte-treated multi-wall carbon nanotubes, and shows reversible capacity of 60000 mAh g(-1) at 1 A g(-1) (≈1000 Wh kg(-1) ) and runs for 200 cycles with controlled capacity of 2000 mAh g(-1) at charge voltage clean recycling and utilization of CO2 . PMID:27089434

  18. CO2 emissions in the World in 2013

    International Nuclear Information System (INIS)

    This publication presents and comments data of CO2 emissions in the world and their evolution. It more particularly addresses CO2 emissions due to energy combustion which represent more than 80 per cent of these emissions or 62 per cent of greenhouse gas emissions, and which increased in 2013 with respect to 2012 (+ 2.2 pc). The distribution of CO2 emissions due to energy combustion in different continents and regions is indicated (levels in 1990, 2012 and 2013, evolutions). The decrease of the CO2 emission intensity with respect to the GDP is briefly commented (evolution since 1970), as well as the level of CO2 emissions per inhabitant in China with respect to that in the EU (evolutions since 1970). The evolution of CO2 emissions is then analysed with respect to different determining parameters according to the Kaya equation (population, GDP, primary energy consumption and their evolution or relationship one to each other)

  19. CO2 measurements during transcranial Doppler examinations in headache patients

    DEFF Research Database (Denmark)

    Thomsen, L L; Iversen, Helle Klingenberg

    1994-01-01

    Transcranial Doppler (TCD) examinations are increasingly being used in studies of headache pathophysiology. Because blood velocity is highly dependent on PCO2, these parameters should be measured simultaneously. The most common way of performing measurements during TCD examinations is as end......-tidal pCO2 with a capnograph. When patients are nauseated and vomit, as in migraine, the mask or mouthpiece connected to the capnograph represents a problem. We therefore evaluated whether a transcutaneous pCO2 electrode was as useful as the capnograph for pCO2 measurements in TCD examinations. We...... conclude that this is not the case, and recommend capnographic end-tidal pCO2 measurements during TCD examinations. However, transcutaneous pCO2 measurements may represent a supplement to spot measurements of end-tidal pCO2 in stable conditions when long-term monitoring is needed, and the mask or...

  20. New era for CO2 as a working fluid

    International Nuclear Information System (INIS)

    During the past decade there has been extensive international activity to find acceptable alternatives to ozone-depleting CFC and HCFC substances that have been widely used as working fluids in refrigerating and heat pump plants. At present, the so-called natural working fluids constitute the most environmentally friendly alternative, and they include first of all ammonia, hydrocarbons and carbon dioxide (CO2). NTNU and SINTEF Energy Research, Norway, have been pioneers in the development of refrigerating and heat pump systems that use CO2 as a working fluid. The favourable technical and environmental properties of CO2 as well as the promising results have now led to considerable international interest in CO2 technology for refrigerating and heat pump applications. Two examples are international licensing for Norwegian CO2 technology and co-operation with Indonesia on CO2 for refrigeration

  1. CO2 absorption characteristics of nanoparticle suspensions in methanol

    International Nuclear Information System (INIS)

    Recently there have been growing concerns that anthropogenic carbon dioxide (CO2) emissions cause the global warming problem. Therefore, the cutting edge technologies for the reduction, separation and collection of the CO2 are very important to alleviate this problem. The best methods for reducing the CO2 emission are to increase the energy efficiency and to remove it from the power plant. The CO2 absorption from the syngas in the integrated gasification combined cycle (IGCC) might increase the energy efficiency of the power generation systems, which also contribute to mitigate the global warming. In this study, the suspensions of nanoparticles in methanol called the nanofluid are developed and estimated to apply it to absorb CO2 gas in the IGCC systems. The nanofluids are prepared by the ultrasonic treatment and show the good stability. It is found that the CO2 absorption rate by the nanofluid is enhanced up to ∼8.3% compared to the pure methanol

  2. Simulation of CO2–water–rock interactions on geologic CO2 sequestration under geological conditions of China

    International Nuclear Information System (INIS)

    Highlights: • We determined the feasibilities of geologic CO2 sequestration in China. • We determined the formation of gibbsite suggested CO2 can be captured by rocks. • We suggested the mechanisms of CO2–water–rock interactions. • We found the corrosion and dissolution of the rock increased as temperature rose. -- Abstract: The main purpose of this study focused on the feasibility of geologic CO2 sequestration within the actual geological conditions of the first Carbon Capture and Storage (CCS) project in China. This study investigated CO2–water–rock interactions under simulated hydrothermal conditions via physicochemical analyses and scanning electron microscopy (SEM). Mass loss measurement and SEM showed that corrosion of feldspars, silica, and clay minerals increased with increasing temperature. Corrosion of sandstone samples in the CO2-containing fluid showed a positive correlation with temperature. During reaction at 70 °C, 85 °C, and 100 °C, gibbsite (an intermediate mineral product) formed on the sample surface. This demonstrated mineral capture of CO2 and supported the feasibility of geologic CO2 sequestration. Chemical analyses suggested a dissolution–reprecipitation mechanism underlying the CO2–water–rock interactions. The results of this study suggested that mineral dissolution, new mineral precipitation, and carbonic acid formation-dissociation are closely interrelated in CO2–water–rock interactions

  3. Density-driven enhanced dissolution of injected CO2 during long-term CO2 geological storage

    Indian Academy of Sciences (India)

    Wei Zhang

    2013-10-01

    Geological storage of CO2 in deep saline formations is increasingly seen as a viable strategy to reduce the release of greenhouse gases into the atmosphere. However, possible leakage of injected CO2 from the storage formation through vertical pathways such as fractures, faults and abandoned wells is a huge challenge for CO2 geological storage projects. Thus, the density-driven fluid flow as a process that can accelerate the phase change of injected CO2 from supercritical phase into aqueous phase is receiving more and more attention. In this paper, we performed higher-resolution reactive transport simulations to investigate the possible density-driven fluid flow process under the ‘real’ condition of CO2 injection and storage. Simulation results indicated that during CO2 injection and geological storage in deep saline formations, the higher-density CO2-saturated aqueous phase within the lower CO2 gas plume migrates downward and moves horizontally along the bottom of the formation, and the higher-density fingers within the upper gas plume propagate downward. These density-driven fluid flow processes can significantly enhance the phase transition of injected CO2 from supercritical phase into aqueous phase, consequently enhancing the effective storage capacity and long-term storage security of injected CO2 in saline formations.

  4. Noble gas and carbon isotopic evidence for CO2-driven silicate dissolution in a recent natural CO2 field

    Science.gov (United States)

    Dubacq, Benoît; Bickle, Mike J.; Wigley, Max; Kampman, Niko; Ballentine, Chris J.; Sherwood Lollar, Barbara

    2012-08-01

    Secure storage of anthropogenic carbon dioxide (CO2) in geological reservoirs requires predicting gas-water-rock interactions over millennial timescales. Noble gases and carbon isotope measurements can be used to shed light on the nature of competing dissolution-precipitation processes over different timescales, from the fast dissolution of gaseous CO2 in groundwater to more sluggish reactions involving dissolution and precipitation of newly formed minerals in the reservoir. Here we study a compilation of gas analyses including noble gases and δ13C of CO2 from nine different natural CO2 reservoirs. Amongst these reservoirs, the Bravo Dome CO2 field (New Mexico, USA) shows distinct geochemical trends which are explained by degassing of noble gases from groundwater altering the composition of the gas phase. This groundwater degassing is synchronous with the dissolution of CO2 in groundwater. Progressive creation of alkalinity via CO2-promoted mineral dissolution is required to explain the observed positive correlation between CO2/3He and δ13C of the gas phase, a unique feature of Bravo Dome. The differences between Bravo Dome and other natural CO2 reservoirs are likely explained by the more recent filling of Bravo Dome, reflecting CO2-water-rock interactions over thousands of years rather than over millions of years in older reservoirs.

  5. Results of a European interlaboratory comparison on CO2 sorption on activated carbon and coals

    Science.gov (United States)

    Gensterblum, Yves; Busch, Andreas; Krooss, Bernhard; de Weireld, Guy; Billemont, Pierre; van Hemert, Patrick; Wolf, Karl-Heinz

    2013-04-01

    For the assessment of CO2 storage in coal seams or enhanced coalbed methane production (ECBM), the sorption properties of natural coals are important parameters. Since more and more laboratories worldwide are concerned with measurements of gas sorption on coal it is indispensable to establish quality standards for such experiments. The first two interlaboratory studies on CO2 sorption on coal (Goodman et al. 2004, 2007) revealed a poor agreement of sorption isotherms among the participating laboratories, particularly in the high-pressure range. During the MOVECBM (http://www.movecbm.eu/) project funded by the European Commission (6th framework), an interlaboratory comparison of CO2 sorption on selected coals and activated carbon was initiated. Measurements were performed on dry samples at 45° C using the manometric and the gravimetric method. up to a final pressure of 15 MPa. The first set of high-pressure sorption measurements was performed on a Filtrasorb 400 activated carbon sample in order to minimise heterogeneity effects and to optimize the experimental procedures for the individual (manometric or gravimetric) methods (Gensterblum et al. 2009). Since comparability for the activated carbon was excellent, the measurements were continued using natural coals of various rank (anthracite, bituminous coal and lignite) to study the influence of heterogeneities and varying starting conditions on the CO2 sorption properties (Gensterblum et al. 2010). Compared to the poor reproducibility observed in previous interlaboratory studies (Goodman et al., 2004, 2007) this European study showed excellent agreement (coals" IJCG, 2010, 84, 115-124 Gensterblum Y., P. van Hemert, P. Billemont, A. Busch, D. Charriére, D. Li, B.M. Krooss, G. de Weireld, D. Prinz , K.-H.A.A. Wolf, "European inter-laboratory comparison of high pressure CO2 sorption isotherms. I: Activated carbon" Carbon 47 ( 2009 ) 2958 -2969 Goodman, A.L., Busch, A., Duffy, G., Fitzgerald, J.E., Gasem, K

  6. Statistical methods for ranking data

    CERN Document Server

    Alvo, Mayer

    2014-01-01

    This book introduces advanced undergraduate, graduate students and practitioners to statistical methods for ranking data. An important aspect of nonparametric statistics is oriented towards the use of ranking data. Rank correlation is defined through the notion of distance functions and the notion of compatibility is introduced to deal with incomplete data. Ranking data are also modeled using a variety of modern tools such as CART, MCMC, EM algorithm and factor analysis. This book deals with statistical methods used for analyzing such data and provides a novel and unifying approach for hypotheses testing. The techniques described in the book are illustrated with examples and the statistical software is provided on the authors’ website.

  7. Global spatially explicit CO2 emission metrics for forest bioenergy

    OpenAIRE

    Francesco Cherubini; Mark Huijbregts; Georg Kindermann; Rosalie Van Zelm; Marijn van der Velde; Konstantin Stadler; Anders Hammer Strømman

    2016-01-01

    Emission metrics aggregate climate impacts of greenhouse gases to common units such as CO2-equivalent (CO2-eq.). Examples include the global warming potential (GWP), the global temperature change potential (GTP) and the absolute sustaied emission temperature (aSET). Despite the importance of biomass as a primary energy supplier in existing and future scenarios, emission metrics for CO2 from forest bioenergy are only available on a case-specific basis. Here, we produce global spatially explici...

  8. Evaluation of Stirling cooler system for cryogenic CO2 capture

    OpenAIRE

    Song, Chun Feng; Kitamura, Yutaka; Li, Shu Hong

    2012-01-01

    In previous research, a cryogenic system based on Stirling coolers has been developed. In this work, the novel system was applied on CO2 capture from post-combustion flue gas and different process parameters (i.e. flow rate of feed gas, temperature of Stirling cooler and operating condition) were investigated to obtain the optimal performance (CO2 recovery and energy consumption). From the extensive experiments, it was concluded that the cryogenic system could realize CO2 capture without solv...

  9. A role for atmospheric CO2 in preindustrial climate forcing

    OpenAIRE

    Thomas B. Van Hoof; Wagner-Cremer, Friederike; Kürschner, Wolfram M.; Visscher, Henk

    2008-01-01

    Complementary to measurements in Antarctic ice cores, stomatal frequency analysis of leaves of land plants preserved in peat and lake deposits can provide a proxy record of preindustrial atmospheric CO2 concentration. CO2 trends based on leaf remains of Quercus robur (English oak) from the Netherlands support the presence of significant CO2 variability during the first half of the last millennium. The amplitude of the reconstructed multidecadal fluctuations, up to 34 parts per million by volu...

  10. Including dynamic CO2 intensity with demand response

    International Nuclear Information System (INIS)

    Hourly demand response tariffs with the intention of reducing or shifting loads during peak demand hours are being intensively discussed among policy-makers, researchers and executives of future electricity systems. Demand response rates have still low customer acceptance, apparently because the consumption habits requires stronger incentive to change than any proposed financial incentive. An hourly CO2 intensity signal could give customers an extra environmental motivation to shift or reduce loads during peak hours, as it would enable co-optimisation of electricity consumption costs and carbon emissions reductions. In this study, we calculated the hourly dynamic CO2 signal and applied the calculation to hourly electricity market data in Great Britain, Ontario and Sweden. This provided a novel understanding of the relationships between hourly electricity generation mix composition, electricity price and electricity mix CO2 intensity. Load shifts from high-price hours resulted in carbon emission reductions for electricity generation mixes where price and CO2 intensity were positively correlated. The reduction can be further improved if the shift is optimised using both price and CO2 intensity. The analysis also indicated that an hourly CO2 intensity signal can help avoid carbon emissions increases for mixes with a negative correlation between electricity price and CO2 intensity. - Highlights: • We present a formula for calculating hybrid dynamic CO2 intensity of electricity generation mixes. • We apply the dynamic CO2 Intensity on hourly electricity market prices and generation units for Great Britain, Ontario and Sweden. • We calculate the spearman correlation between hourly electricity market price and dynamic CO2 intensity for Great Britain, Ontario and Sweden. • We calculate carbon footprint of shifting 1 kWh load daily from on-peak hours to off-peak hours using the dynamic CO2 intensity. • We conclude that using dynamic CO2 intensity for load shift

  11. CO2 capture from oxy-fuel combustion power plants

    OpenAIRE

    Hu, Yukun

    2011-01-01

    To mitigate the global greenhouse gases (GHGs) emissions, carbon dioxide (CO2) capture and storage (CCS) has the potential to play a significant role for reaching mitigation target. Oxy-fuel combustion is a promising technology for CO2 capture in power plants. Advantages compared to CCS with the conventional combustion technology are: high combustion efficiency, flue gas volume reduction, low fuel consumption, near zero CO2 emission, and less nitrogen oxides (NOx) formation can be reached sim...

  12. Possible impacts of CO2 storage on the marine environment

    International Nuclear Information System (INIS)

    This study examined the potential impacts of deep-sea carbon dioxide (CO2) sequestration on the marine environment. The upper layers of oceans are currently saturated with CO2, while deeper ocean waters remain undersaturated. Arctic and Antarctic waters have higher uptake rates of CO2 due to their lower temperatures. CO2 deposited in Arctic and Antarctic waters sinks to the bottom of the ocean, and is then transported to equatorial latitudes, where stored amounts of CO2 that are not fixed by biochemical processes will be released and enter the atmosphere again after a period of approximately 1000 years. Nearly 50 per cent of CO2 fixation occurs as a result of phytoplankton growth, which is dependent on the availability of a range of nutrients, essential trace metals, and optimal physical conditions. Fertilization-induced CO2 fixation in the sediments of southern oceans will result in nutrient depletion of bottom layers, which will in turn result in lower primary production levels at equatorial latitudes. Current modelling approaches to CO2 injection assume that the injected CO2 will dissolve in a plume extending 100 m around a riser. Retention times of several hundred years are anticipated. However, further research is needed to investigate the efficacy of CO2 deep ocean storage technologies. Increased CO2 uptake can also increase the formation of bicarbonate (HCO3) acidification, decrease pH values, and inhibit the formation of biomass in addition to impacting on the calcification of many organisms. It was concluded that ocean storage by injection or deep storage is an untenable option at present due to the fact that the effects of excessive CO2 in marine environments are not fully understood. 22 refs., 2 tabs

  13. Direct observation of the oceanic CO2 increase revisited

    OpenAIRE

    Brewer, Peter G.; Goyet, Catherine; Friederich, Gernot

    1997-01-01

    We show, from recent data obtained at specimen North Pacific stations, that the fossil fuel CO2 signal is strongly present in the upper 400 m, and that we may consider areal extrapolations from geochemical surveys to determine the magnitude of ocean fossil fuel CO2 uptake. The debate surrounding this topic is illustrated by contrasting reports which suggest, based upon atmospheric observations and models, that the oceanic CO2 sink is small at these latitudes; or th...

  14. Geothermal energy combined with CO2 sequestration: An additional benefit

    OpenAIRE

    Salimi, H.; Wolf, K.H.A.A.; Bruining, J.

    2012-01-01

    In this transition period from a fossil-fuel based society to a sustainable-energy society, it is expected that CO2 capture and subsequent sequestration in geological formations plays a major role in reducing greenhouse gas emissions. An alternative for CO2 emission reduction is to partially replace conventional-energy for heating and cooling buildings (e.g., cogeneration units) with geothermal energy. A mixture of CO2 with cold return water injected into geothermal reservoirs can be the inte...

  15. BARRIER EFFECT IN CO2 CAPTURE AND STORAGE FEASIBILITY STUDY

    OpenAIRE

    Montegrossi, G.; CNR-IGG Firenze; Cantucci, B.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Roma1, Roma, Italia; Bicocchi, G.; Department of Earth Science Via La Pira 4, 50121 Florence (Italy); Vaselli, O.; Department of Earth Science Via La Pira 4, 50121 Florence (Italy); Quattrocchi, F.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Roma1, Roma, Italia

    2009-01-01

    CO2 Capture & Storage (CCS) in saline aquifer is one of the most promising technologies for reducing anthropogenic emission of CO2. Feasibility studies for CO2 geo-sequestration in Italy have increased in the last few years. Before planning a CCS plant an appropriate precision and accuracy in the prediction of the reservoir evolution during injection, in terms of both geochemical calculation and fluid flow properties, is demanded. In this work a geochemical model will be presented for an offs...

  16. PSO 7171 - Oxyfuel Combustion for below zero CO2 emissions

    OpenAIRE

    Toftegaard, Maja Bøg; Brix, Jacob; Hansen, Brian Brun; Putluru, Siva Sankar Reddy; Montgomery, Melanie; Hansen, Kim G; Fisker, Dennis; Jensen, Peter Arendt; Glarborg, Peter; Jensen, Anker Degn

    2011-01-01

    The reduction of CO2 emissions is of highest concern in relation to limiting the anthropogenic impacts on the environment. Primary focus has gathered on the large point sources of CO2 emissions constituted by large heat and power stations and other heavy, energy-consuming industry. Solutions are sought which will enable a significant reduction of the anthropogenic CO2 emissions during the transformation period from the use of fossil fuels to renewable sources of energy. Carbon capture and sto...

  17. Compatibility of Medical-Grade Polymers with Dense CO2

    OpenAIRE

    A. Jiménez; Thompson, G.L.; Matthews, M A; Davis, T. A.; Crocker, K.; Lyons, J S; Trapotsis, A

    2007-01-01

    This study reports the effect of exposure to liquid carbon dioxide on the mechanical properties of selected medical polymers. The tensile strengths and moduli of fourteen polymers are reported. Materials were exposed to liquid CO2, or CO2 + trace amounts of aqueous H2O2, at 6.5 MPa and ambient temperature. Carbon dioxide uptake, swelling, and distortion were observed for the more amorphous polymers while polymers with higher crystallinity showed little effect from CO2 exposure. Changes in ten...

  18. Consumption-based accounting of CO2 emissions

    OpenAIRE

    S. J. Davis; K. Caldeira

    2010-01-01

    CO2 emissions from the burning of fossil fuels are the primary cause of global warming. Much attention has been focused on the CO2 directly emitted by each country, but relatively little attention has been paid to the amount of emissions associated with the consumption of goods and services in each country. Consumption-based accounting of CO2 emissions differs from traditional, production-based inventories because of imports and exports of goods and services that, either directly or indirectl...

  19. Uncertainties of predictions of future atmosphere CO2 concentrations

    International Nuclear Information System (INIS)

    Linear carbon cycle models, tuned to reproduce the CO2 increase observed at Mauna Loa, independently of their individual assumptions, predict almost identical CO2 concentration trends for fossil energy scenarios assuming a slightly increasing production in the next few decades. The basic information for such prognoses therefore is the airborne fraction observed over the last 20 years. Uncertainties in this quantity are due to possible errors in the estimate of fossil fuel consumption and the corresponding CO2 emission, possible natural fluctuations in the baseline CO2 level, and uncertainties regarding the biospheric CO2 input and uptake as a result of deforestation and reforestation and land management. Depending on different assumptions the effective airborne fraction, defined as the ratio of CO2 increase due to fossil fuel CO2 alone to the integrated CO2 production, might be as low as 0.38 or as high as 0.72, compared to the apparent airborne fraction of 0.55. The effective airborne fraction derived from carbon cycle models, considering only the CO2 uptake by the ocean, lies in the range 0.60--0.70. A value as low as 0.40 seems therefore highly improbable. A high biospheric anthropogenic CO2 input therefore must have been accompanied by a high CO2 fertilization effect. Model considerations, however, are not in contradiction with a high biospheric input with the maximum production before 1958, which also would imply low preindustrial CO2 concentrations in the range 270--280 ppm as reported recently

  20. THE INFLUENCE OF CO2 ON WELL CEMENT

    Directory of Open Access Journals (Sweden)

    Nediljka Gaurina-Međimurec

    2010-12-01

    Full Text Available Carbon capture and storage is one way to reduce emissions of greenhouse gases in the atmosphere. Underground gas storage operations and CO2 sequestration in aquifers relay on both the proper wellbore construction and sealing properties of the cap rock. CO2 injection candidates may be new wells or old wells. In both cases, the long-term wellbore integrity (up to 1 000 years is one of the key performance criteria in the geological storage of CO2. The potential leakage paths are the migration CO2 along the wellbore due to poor cementation and flow through the cap rock. The permeability and integrity of the set cement will determine how effective it is in preventing the leakage. The integrity of the cap rock is assured by an adequate fracture gradient and by sufficient set cement around the casing across the cap rock and without a micro-annulus. CO2 storage in underground formations has revived the researc of long term influence of the injected CO2 on Portland cements and methods for improving the long term efficiency of the wellbore sealant. Some researchers predicted that set cement will fail when exposed to CO2 leading to potential leakage to the atmosphere or into underground formations that may contain potable water. Other researchers show set cement samples from 30 to 50 year-old wells (CO2 EOR projects that have maintained sealing integrity and prevented CO2 leakage, in spite of some degree of carbonation. One of reasons for the discrepancy between certain research lab tests and actual field performance measurements is the absence of standard protocol for CO2 resistance-testing devices, conditions, or procedures. This paper presents potential flow paths along the wellbore, CO2 behaviour under reservoir conditions, and geochemical alteration of hydrated Portland cement due to supercritical CO2 injection.

  1. Real-World CO2 Impacts of Traffic Congestion

    OpenAIRE

    Barth, Matthew; Boriboonsomsin, Kanok

    2008-01-01

    Transportation plays a significant role in carbon dioxide (CO2) emissions, accounting for approximately a third of the United States’ inventory. In order to reduce CO2 emissions in the future, transportation policy makers are looking to make vehicles more efficient and increasing the use of carbon-neutral alternative fuels. In addition, CO2 emissions can be lowered by improving traffic operations, specifically through the reduction of traffic congestion. This paper examines traffic congesti...

  2. CO2 Fixation by Membrane Separated NaCl Electrolysis

    OpenAIRE

    Hyun Sic Park; Ju Sung Lee; JunYoung Han; Sangwon Park; Jinwon Park; Byoung Ryul Min

    2015-01-01

    Atmospheric concentrations of carbon dioxide (CO2), a major cause of global warming, have been rising due to industrial development. Carbon capture and storage (CCS), which is regarded as the most effective way to reduce such atmospheric CO2 concentrations, has several environmental and technical disadvantages. Carbon capture and utilization (CCU), which has been introduced to cover such disadvantages, makes it possible to capture CO2, recycling byproducts as resources. However, CCU also requ...

  3. Evaluating uncertain CO2 abatement over the very long term

    OpenAIRE

    Gerlagh, R.; Zwaan, B.C.C. van der

    2011-01-01

    Climate change research with the economic methodology of cost–benefit analysis is challenging because of valuation and ethical issues associated with the long delays between CO2 emissions and much of their potential damages, typically of several centuries. The large uncertainties with which climate change impacts are known today and the possibly temporary nature of some envisaged CO2 abatement options exacerbate this challenge. For example, potential leakage of CO2 from geological reservoirs,...

  4. Quantifying CO2 abatement costs in the power sector

    International Nuclear Information System (INIS)

    CO2 cap-and-trade mechanisms and CO2 emission taxes are becoming increasingly widespread. To assess the impact of a CO2 price, marginal abatement cost curves (MACCs) are a commonly used tool by policy makers, providing a direct graphical link between a CO2 price and the expected abatement. However, such MACCs can suffer from issues related to robustness and granularity. This paper focuses on the relation between a CO2 emission cost and CO2 emission reductions in the power sector. The authors present a new methodology that improves the understanding of the relation between a CO2 cost and CO2 abatement. The methodology is based on the insight that CO2 emissions in the power sector are driven by the composition of the conventional power portfolio, the residual load and the generation costs of the conventional units. The methodology addresses both the robustness issue and the granularity issue related to MACCs. The methodology is based on a bottom-up approach, starting from engineering knowledge of the power sector. It offers policy makers a new tool to assess CO2 abatement options. The methodology is applied to the Central Western European power system and illustrates possible interaction effects between, e.g., fuel switching and renewables deployment. - Highlights: • We present a new methodology on the CO2 cost-emission relation in the power sector. • Main objective of the methodology is to deepen the understanding of this relation. • CO2 emissions are driven by installed capacity, load and generation costs. • The robustness and granularity issues linked to MACCs are addressed. • We apply the methodology to the 2012 Central Western European power sector

  5. Bubble nucleation in polymer–CO_2 mixtures

    OpenAIRE

    Xu, Xiaofei; Cristancho, Diego E.; Costeux, Stéphane; Wang, Zhen-Gang

    2013-01-01

    We combine density-functional theory with the string method to calculate the minimum free energy path of bubble nucleation in two polymer–CO_2 mixture systems, poly(methyl methacrylate) (PMMA)–CO_2 and polystyrene (PS)–CO_2. Nucleation is initiated by saturating the polymer liquid with high pressure CO_2 and subsequently reducing the pressure to ambient condition. Below a critical temperature (Tc), we find that there is a discontinuous drop in the nucleation barrier as a function of increased...

  6. CO2 emissions by the economic circuit in France

    International Nuclear Information System (INIS)

    Before commenting various statistical data on CO2 emission in France, this report explains how these data have been established according to the 'Stiglitz' Commission recommendations, i.e. by integrating CO2 emissions in the national accounts. While commenting the evolutions of CO2 emissions in relationship with economic activity and giving table of world data, it outlines that France represents 3% of the World GDP, 1.3% of CO2 emissions and 1% of the population. The relationship between standard of living and pollutant emissions are commented. As far as France is concerned and with a comparison with world data the shares of different sources of energy and of the different sectors in CO2 emissions are indicated and commented. The report comments the influence of the domestic demand on foreign CO2 emissions, the differences between households in terms of CO2 emissions with respect to their revenues, the shares of household consumption and of CO2 emissions among expense items, the influence of socio-professional, of age, and of household composition category on CO2 emissions. Some methodological and computational aspects are given

  7. Mesoscale modelling of atmospheric CO2 across Denmark

    DEFF Research Database (Denmark)

    Lansø, Anne Sofie

    2016-01-01

     have a significant impact on the annual air–sea CO2 exchange. A simulation with constant monthly fields of atmospheric CO2, reduced the winter release of CO2 for the six year period, resulting in an increase of 67% in the average annual uptake by the Baltic Sea and Danish inner waters. The inclusion of short......-term variability in surface water pCO2 was included, the annual uptake changed to an annual release of atmospheric CO2. Besides showing the impact of short-term variability in surface water pCO2, these simulations also showed that the choice of surface water pCO2 fields had a notable impact on the annual air–sea CO...... to take up an amount of CO2 that nearly corresponds to all the CO2 emitted by fossil fuel use in Denmark. However, the biospheric uptake might have been overestimated. The spatiotemporal resolution on land and sea has been greatly improved for the focus area during this study. The calculations...

  8. Modeling of CO2 absorber using an AMP solution

    DEFF Research Database (Denmark)

    Gabrielsen, Jostein; Michelsen, Michael Locht; Stenby, Erling Halfdan;

    2006-01-01

    Abstract: An explicit model for carbon dioxide (CO2) solubility in an aqueous solution of 2-amino-2-methyl-1-propanol (AMP) has been proposed and an expression for the heat of absorption of CO2 has been developed as a function of loading and temperature. A rate-based steady-state model for CO2 ab...... absorption of CO2 into an AMP solution in a packed tower and validated against pilot-plant data from the literature. (c) 2006 American Institute of Chemical Engineers....

  9. CO2 Emissions From Fuel Combustion. Highlights. 2013 Edition

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2013-07-01

    In the lead-up to the UN climate negotiations in Warsaw, the latest information on the level and growth of CO2 emissions, their source and geographic distribution will be essential to lay the foundation for a global agreement. To provide input to and support for the UN process, the IEA is making available for free download the ''Highlights'' version of CO2 Emissions from Fuel Combustion now for sale on IEA Bookshop. This annual publication contains, for more than 140 countries and regions: estimates of CO2 emissions from 1971 to 2011; selected indicators such as CO2/GDP, CO2/capita, CO2/TPES and CO2/kWh; a decomposition of CO2 emissions into driving factors; and CO2emissions from international marine and aviation bunkers, key sources, and other relevant information. The nineteenth session of the Conference of the Parties to the Climate Change Convention (COP-19), in conjunction with the ninth meeting of the Parties to the Kyoto Protocol (CMP 9), met in Warsaw, Poland from 11 to 22 November 2013. This volume of ''Highlights'', drawn from the full-scale study, was specially designed for delegations and observers of the meeting in Warsaw.

  10. Annual CO2 balance of a temperate bog

    OpenAIRE

    Lund, Magnus; Lindroth, Anders; Christensen, Torben R.; Ström, Lena

    2011-01-01

    Peatlands are generally small sinks for atmospheric CO2. However, the sustainability of this sink functioning is threatened in a changing climate. We measured the CO2 exchange in a temperate bog between August 2005 and July 2006 using the eddy covariance technique. During this period, the CO2 balance was –78.6 ± 20.0 g CO2 m-2 yr-1, which is a lower uptake than others have reported for comparable ecosystems, but in accordance with average Holocene uptake rates. Average winter emissions were s...

  11. Asymmetric Synthesis Using Enzymes in Supercritical CO2

    Institute of Scientific and Technical Information of China (English)

    T. Matsuda

    2005-01-01

    @@ 1Introduction Great efforts have been extended to catalysis in supercritical CO2 (scCO2) since the early 1990's due to the environmental friendliness, high diffusivity, high solubilizing power, easiness of the product separation,etc.. A combined process of scCO2 and enzymatic catalyst system would be a promising synthetic tool to produce optically active compounds because the enzyme has advantages of being natural and having high enantioselectivity in nature. Here we report asymmetric synthesis using lipase and alcohol dehydrogenase in scCO2[1,2].

  12. Comparison of regional and ecosystem CO2 fluxes

    DEFF Research Database (Denmark)

    Gryning, Sven-Erik; Søgaard, Henrik; Batchvarova, Ekaterina

    2009-01-01

    A budget method to derive the regional surface flux of CO2 from the evolution of the boundary layer is presented and applied. The necessary input for the method can be deduced from a combination of vertical profile measurements of CO2 concentrations by i.e. an airplane, successive radio-soundings......A budget method to derive the regional surface flux of CO2 from the evolution of the boundary layer is presented and applied. The necessary input for the method can be deduced from a combination of vertical profile measurements of CO2 concentrations by i.e. an airplane, successive radio...

  13. Wirkungsabschätzung CO2-Abgabe, Synthese

    OpenAIRE

    Müller, André; Schoch, Tobias; Mattmann, Michael; Thalmann, Philippe; Vielle, Marc; Hulliger, Beat

    2015-01-01

    Seit dem 1.1.2008 wird auf den fossilen Brennstoffen Öl und Erdgas die CO2-Abgabe erhoben. Diese Lenkungsabgabe soll einen Beitrag zur Reduktion der CO2-Emissionen im Rahmen des CO2-Gesetzes leisten. Die Abgabe verteuert die Energieträger Öl und Erdgas im Vergleich zu den nicht besteuerten Energiequellen (bspw. erneuerbare Energien). Mit dem Eingriff ins Preisgefüge sollen finanzielle Anreize geschaffen werden, um Haushalte und Unternehmen zu einem Wechsel von fossilen, CO2-intensiven Energie...

  14. Removal of CO2 from gas power plants

    International Nuclear Information System (INIS)

    As part of the Norges teknisk naturvitenskapelige universitet (NTNU) effort in the global and national energy and environmental issues, a study has focused on how to meet the challenge of reducing the CO2-emissions related to the Kyoto treaty. Three concepts for collecting CO2 from natural gas fired combined gas/steam turbine power plants have been evaluated and compared with respect to fuel to electricity conversion efficiency. These concepts comprise chemical absorption of CO2 from exhaust gases, stoichiometric combustion with oxygen and fuel de carbonisation. Removing CO2 reduces the efficiency with about 7-10 percentage points

  15. CO2 Sink/Source in the Indonesian Seas

    KAUST Repository

    Kartadikaria, Aditya

    2015-04-01

    Two distinct CO2 sink/source characteristics appeared from the compiled observed data 1984-2013 in the tropical Indonesian seas. The western part persistently emits CO2 to the atmosphere, while the eastern is rather dynamic which emits and absorbs smaller amount of CO2 to and from atmosphere, respectively. The segregation is proximal to the virtual Wallace line, where in the continental shelf is located. Lower salinity and higher silicate condition in the western part influenced the higher pCO2 condition in Java Sea. Temperature is found to have a limited influence to control different characteristic in the west and east, but SST change of 2.0 0C during La Ninã condition effectively reduced the source amount of CO2 by 50% compared to Normal year condition. Yet, during La Ninã, higher wind speed increases CO2 flux twice compared to Normal year. In the continental shelf area where CO2 sink area is found, 29 years data showed that pCO2 trend is increasing ±0.6-3.8 μatm/year. From this study, the overall areas have a significant source of CO2 of approximately 10 - 24 μatm.

  16. Enhanced Oil Recovery with CO2 Capture and Sequestration

    Energy Technology Data Exchange (ETDEWEB)

    Andrei, Maria; De Simoni, Michela; Delbianco, Alberto; Cazzani, Piero; Zanibelli, Laura

    2010-09-15

    This paper presents the results of a feasibility study aimed at extending the production life of a small oilfield in Italy through EOR, employing the CO2 captured from the flue gas streams of the refinery nearby. The EOR operation allows the recovery of additional reserves while a consistent amount of the CO2 injected remains permanently stored into the reservoir. The screening process selection for EOR-CO2 and the main elements of the pilot project for the proper upstream-downstream integration will be described. Evaluation of EOR-CO2 extension to other oilfields and its effect on oil production and project's economics will be reported.

  17. A CO2-strategy for BTC [Belgian Development Agency

    Energy Technology Data Exchange (ETDEWEB)

    Bailly, J. [Prospect C and S, Brussels (Belgium); Hanekamp, E. [Partners for Innovation, Amsterdam (Netherlands)

    2008-09-15

    The CO2 footprint is determined the CO2 strategy is developed for the Belgian Technical Cooperation (BTC). BTC is the Belgian agency for development cooperation, and finances development projects in 23 partner countries. The CO2 footprint covered BTC's activities in 2007 in all their offices worldwide. Footprint and strategy were finalised and adopted by the Executive Board at the end of 2008. Meanwhile, the BTC began with the introduction of the proposed strategy. Partners for Innovation and Prospect were asked to support the introduction of the strategy and to determine the CO2 footprint of 2008.

  18. Global spatially explicit CO2 emission metrics for forest bioenergy

    Science.gov (United States)

    Cherubini, Francesco; Huijbregts, Mark; Kindermann, Georg; van Zelm, Rosalie; van der Velde, Marijn; Stadler, Konstantin; Strømman, Anders Hammer

    2016-02-01

    Emission metrics aggregate climate impacts of greenhouse gases to common units such as CO2-equivalents (CO2-eq.). Examples include the global warming potential (GWP), the global temperature change potential (GTP) and the absolute sustained emission temperature (aSET). Despite the importance of biomass as a primary energy supplier in existing and future scenarios, emission metrics for CO2 from forest bioenergy are only available on a case-specific basis. Here, we produce global spatially explicit emission metrics for CO2 emissions from forest bioenergy and illustrate their applications to global emissions in 2015 and until 2100 under the RCP8.5 scenario. We obtain global average values of 0.49 ± 0.03 kgCO2-eq. kgCO2-1 (mean ± standard deviation) for GWP, 0.05 ± 0.05 kgCO2-eq. kgCO2-1 for GTP, and 2.14·10-14 ± 0.11·10-14 °C (kg yr-1)-1 for aSET. We explore metric dependencies on temperature, precipitation, biomass turnover times and extraction rates of forest residues. We find relatively high emission metrics with low precipitation, long rotation times and low residue extraction rates. Our results provide a basis for assessing CO2 emissions from forest bioenergy under different indicators and across various spatial and temporal scales.

  19. DESIGN AND MECHANICAL INTEGRITY OF CO2 INJECTION WELLS

    OpenAIRE

    Nediljka Gaurina-Međimurec; Borivoje Pašić

    2011-01-01

    Geologic Sequestration (GS) is part of a process known as “carbon capture and storage (CCS)” and represents the process of injecting CO2, into deep subsurface rock formations for long-term storage. For injecting of CO2 existing wells are used as well as new drilled wells. A well represents the most likely route for leakage of CO2 from geologic carbon sequestration. Maintaining mechanical integrity helps prevent the well and wellbore from becoming conduits for CO2 migration out of the injectio...

  20. CO2 to fuel using nuclear power: the French case

    International Nuclear Information System (INIS)

    In France, the majority of the electricity generated is derived from nuclear energy which has a low CO2 footprint. A preliminary analysis showed us that, in the French specific context, without any new nuclear power plant construction, the emission of several millions tons of CO2 could be avoided by using a CO2 to fuel technology to adjust the electricity produced by nuclear energy to the electricity grid demand. This will not only mitigate CO2 emissions but could also increase nuclear economic competitiveness. Possibilities of direct using nuclear heat are also under investigation, to improve the efficiency of the global system of conversion. (authors)

  1. Effect of CO2 supply strategy on specific energy consumption

    OpenAIRE

    Zwart, de, H.F.

    1998-01-01

    This paper studies the effect of CO2-dosing with exhaust gases on the efficiency of glasshouse tomato production. The paper shows that it can be recommended to ensure a continuing CO2 supply during the warm period. The discussion focuses on exhaust gases as a CO2 source, but the results also elucidate the effects of pure CO2. The efficiency is rated with respect to the ratio between primary energy consumption and biomass production. The computations are made with a greenhouse climate simulati...

  2. Vibrational dynamics of adsorbed CO2: Separability of the CO2 asymmetric stretching mode

    Czech Academy of Sciences Publication Activity Database

    Bludský, Ota; Nachtigall, Petr; Špirko, Vladimír

    2011-01-01

    Roč. 76, č. 6 (2011), s. 669-682. ISSN 0010-0765 R&D Projects: GA MŠk LC512; GA ČR GAP208/11/0436; GA MŠk(CZ) ME10032 Grant ostatní: GA MŠk(CZ) KONTAKT-II(LH)-CH022 Institutional research plan: CEZ:AV0Z40550506 Keywords : adsorption of CO2 * vibrational dynamics * DFT calculations Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 1.283, year: 2011

  3. Ranking nodes in growing networks: When PageRank fails

    Science.gov (United States)

    Mariani, Manuel Sebastian; Medo, Matúš; Zhang, Yi-Cheng

    2015-11-01

    PageRank is arguably the most popular ranking algorithm which is being applied in real systems ranging from information to biological and infrastructure networks. Despite its outstanding popularity and broad use in different areas of science, the relation between the algorithm’s efficacy and properties of the network on which it acts has not yet been fully understood. We study here PageRank’s performance on a network model supported by real data, and show that realistic temporal effects make PageRank fail in individuating the most valuable nodes for a broad range of model parameters. Results on real data are in qualitative agreement with our model-based findings. This failure of PageRank reveals that the static approach to information filtering is inappropriate for a broad class of growing systems, and suggest that time-dependent algorithms that are based on the temporal linking patterns of these systems are needed to better rank the nodes.

  4. CO2 Capture Rate Sensitivity Versus Purchase of CO2 Quotas. Optimizing Investment Choice for Electricity Sector

    Directory of Open Access Journals (Sweden)

    Coussy Paula

    2014-09-01

    Full Text Available Carbon capture technology (and associated storage, applied to power plants, reduces atmospheric CO2 emissions. This article demonstrates that, in the particular case of the deployment phase of CO2 capture technology during which CO2 quota price may be low, capturing less than 90% of total CO2 emissions from power plants can be economically attractive. Indeed, for an electric power company capture technology is interesting, only if the discounted marginal cost of capture is lower than the discounted marginal cost of purchased quotas. When CO2 price is low, it is interesting to have flexibility and reduce the overall capture rate of the site, by stopping the capture system of one of the combustion trains if the site has multiple ones, or by adopting less than 90% CO2 capture rate.

  5. Commercial Reclaiming Recovery of CO2 Emission%CO2排放的商业回收利用

    Institute of Scientific and Technical Information of China (English)

    王玉倩

    2008-01-01

    CO2是最主要的温室气体,其减排和回收利用关系到可持续发展.世界CO2排放185亿~242亿t/a,只有1亿t/a得到利用.主要产品是液体CO2.我国CO2排放已超过30亿t/a,只有80万t/a得到有效利用.利用方式是干冰和液体CO2.液体CO2需求量增长速度为15%~20%,未来5年后年需量达到200万t以上.

  6. Our trial to develop a risk assessment tool for CO2 geological storage (GERAS-CO2GS)

    Science.gov (United States)

    Tanaka, A.; Sakamoto, Y.; Komai, T.

    2012-12-01

    We will introduce our researches about to develop a risk assessment tool named 'GERAS-CO2GS' (Geo-environmental Risk Assessment System, CO2 Geological Storage Risk Assessment System) for 'Carbon Dioxide Geological Storage (Geological CCS)'. It aims to facilitate understanding of size of impact of risks related with upper migration of injected CO2. For gaining public recognition about feasibility of Geological CCS, quantitative estimation of risks is essential, to let public knows the level of the risk: whether it is negligible or not. Generally, in preliminary hazard analysis procedure, potential hazards could be identified within Geological CCS's various facilities such as: reservoir, cap rock, upper layers, CO2 injection well, CO2 injection plant and CO2 transport facilities. Among them, hazard of leakage of injected C02 is crucial, because it is the clue to estimate risks around a specific injection plan in terms of safety, environmental protection effect and economy. Our risk assessment tool named GERAS-CO2GS evaluates volume and rate of retention and leakage of injected CO2 in relation with fractures and/or faults, and then it estimates impact of seepages on the surface of the earth. GERAS-CO2GS has four major processing segments: (a) calculation of CO2 retention and leakage volume and rate, (b) data processing of CO2 dispersion on the surface and ambient air, (c) risk data definition and (d) evaluation of risk. Concerning to the injection site, we defined a model, which is consisted from an injection well and a geological strata model: which involves a reservoir, a cap rock, an upper layer, faults, seabed, sea, the surface of the earth and the surface of the sea. For retention rate of each element of CO2 injection site model, we use results of our experimental and numerical studies on CO2 migration within reservoirs and faults with specific lithological conditions. For given CO2 injection rate, GERAS-CO2GS calculates CO2 retention and leakage of each segment

  7. Leakage and Seepage of CO2 from Geologic Carbon Sequestration Sites: CO2 Migration into Surface Water

    International Nuclear Information System (INIS)

    Geologic carbon sequestration is the capture of anthropogenic carbon dioxide (CO2) and its storage in deep geologic formations. One of the concerns of geologic carbon sequestration is that injected CO2 may leak out of the intended storage formation, migrate to the near-surface environment, and seep out of the ground or into surface water. In this research, we investigate the process of CO2 leakage and seepage into saturated sediments and overlying surface water bodies such as rivers, lakes, wetlands, and continental shelf marine environments. Natural CO2 and CH4 fluxes are well studied and provide insight into the expected transport mechanisms and fate of seepage fluxes of similar magnitude. Also, natural CO2 and CH4 fluxes are pervasive in surface water environments at levels that may mask low-level carbon sequestration leakage and seepage. Extreme examples are the well known volcanic lakes in Cameroon where lake water supersaturated with respect to CO2 overturned and degassed with lethal effects. Standard bubble formation and hydrostatics are applicable to CO2 bubbles in surface water. Bubble-rise velocity in surface water is a function of bubble size and reaches a maximum of approximately 30 cm s-1 at a bubble radius of 0.7 mm. Bubble rise in saturated porous media below surface water is affected by surface tension and buoyancy forces, along with the solid matrix pore structure. For medium and fine grain sizes, surface tension forces dominate and gas transport tends to occur as channel flow rather than bubble flow. For coarse porous media such as gravels and coarse sand, buoyancy dominates and the maximum bubble rise velocity is predicted to be approximately 18 cm s-1. Liquid CO2 bubbles rise slower in water than gaseous CO2 bubbles due to the smaller density contrast. A comparison of ebullition (i.e., bubble formation) and resulting bubble flow versus dispersive gas transport for CO2 and CH4 at three different seepage rates reveals that ebullition and bubble

  8. CO2 Capture Rate Sensitivity Versus Purchase of CO2 Quotas. Optimizing Investment Choice for Electricity Sector

    International Nuclear Information System (INIS)

    Carbon capture technology (and associated storage), applied to power plants, reduces atmospheric CO2 emissions. This article demonstrates that, in the particular case of the deployment phase of CO2 capture technology during which CO2 quota price may be low, capturing less than 90% of total CO2 emissions from power plants can be economically attractive. Indeed, for an electric power company capture technology is interesting, only if the discounted marginal cost of capture is lower than the discounted marginal cost of purchased quotas. When CO2 price is low, it is interesting to have flexibility and reduce the overall capture rate of the site, by stopping the capture system of one of the combustion trains if the site has multiple ones, or by adopting less than 90% CO2 capture rate. (authors)

  9. Separation of biospheric and fossil fuel fluxes of CO2 by atmospheric inversion of CO2 and 14CO2 measurements: Observation System Simulations

    Science.gov (United States)

    Basu, Sourish; Bharat Miller, John; Lehman, Scott

    2016-05-01

    National annual total CO2 emissions from combustion of fossil fuels are likely known to within 5-10 % for most developed countries. However, uncertainties are inevitably larger (by unknown amounts) for emission estimates at regional and monthly scales, or for developing countries. Given recent international efforts to establish emission reduction targets, independent determination and verification of regional and national scale fossil fuel CO2 emissions are likely to become increasingly important. Here, we take advantage of the fact that precise measurements of 14C in CO2 provide a largely unbiased tracer for recently added fossil-fuel-derived CO2 in the atmosphere and present an atmospheric inversion technique to jointly assimilate observations of CO2 and 14CO2 in order to simultaneously estimate fossil fuel emissions and biospheric exchange fluxes of CO2. Using this method in a set of Observation System Simulation Experiments (OSSEs), we show that given the coverage of 14CO2 measurements available in 2010 (969 over North America, 1063 globally), we can recover the US national total fossil fuel emission to better than 1 % for the year and to within 5 % for most months. Increasing the number of 14CO2 observations to ˜ 5000 per year over North America, as recently recommended by the National Academy of Science (NAS) (Pacala et al., 2010), we recover monthly emissions to within 5 % for all months for the US as a whole and also for smaller, highly emissive regions over which the specified data coverage is relatively dense, such as for the New England states or the NY-NJ-PA tri-state area. This result suggests that, given continued improvement in state-of-the art transport models, a measurement program similar in scale to that recommended by the NAS can provide for independent verification of bottom-up inventories of fossil fuel CO2 at the regional and national scale. In addition, we show that the dual tracer inversion framework can detect and minimize biases in

  10. The geomicrobiology of CO2 geosequestration: a focused review on prokaryotic community responses to field-scale CO2 injection

    OpenAIRE

    Andre eMu; Moreau, John W.

    2015-01-01

    Our primary research paper, titled Changes in the deep subsurface microbial biosphere resulting from a field-scale CO2 geosequestration experiment (Mu et al., 2014), demonstrated selective changes to a deep subsurface prokaryotic community as a result of CO2 stress. Analysing geochemical and microbial 16S rRNA gene profiles, we evaluated how in situ prokaryotic communities responded to increased CO2 and the presence of trace organic compounds, and related temporal shifts in phylogeny to chang...

  11. Synergetic effect of carbon nanopore size and surface oxidation on CO2 capture from CO2/CH4 mixtures

    OpenAIRE

    Furmaniak, Sylwester; KOWALCZYK, PIOTR; Terzyk, Artur P.; Gauden, Piotr A.; Harris , P. J. F.

    2013-01-01

    We have studied the synergetic effect of confinement (carbon nanopore size) and surface chemistry (the number of carbonyl groups) on CO2 capture from its mixtures with CH4 at typical operating conditions for industrial adsorptive separation (298 K and compressed CO2CH4 mixtures). Although both confinement and surface oxidation have an impact on the efficiency of CO2/CH4 adsorptive separation at thermodynamics equilibrium, we show that surface functionalization is the most important factor in ...

  12. CO2 - Sequestration on Laboratory Scale: Geochemical Interactions Between Injected CO2, Saline Fluid Phases, and Potential Reservoir Materials

    OpenAIRE

    Beier, Katja

    2012-01-01

    Due to the increasing global energy consumption the CO2 emission of fossil fuel burning power plants is a worldwide problem and contributes significantly to the climate change. As one of the joint research projects within the German GEOTECHNOLOGIEN program the CO2-MoPa project represents the aim of dimension and risk analyses for subterrestrial CO2 sequestration by virtual scenario investigations. In addition to numerical and process oriented modeling as well as the compilation and validat...

  13. A study of CO2 precipitation method considering an ionic CO2 and Ca(OH)2 slurry

    International Nuclear Information System (INIS)

    CCS (carbon capture and storage) is the most popular technology used for the reduction of CO2 in the post-combustion stage. However, the CCS process has some disadvantages including uncertainty about the stability of the land that is used to store the separated CO2. Consequently, CCU (carbon capture and utilization) technologies have recently received increased attention as a possible replacement for CCS. In this study, we utilized CO2 fixation methods by using the metal carbonate mechanism. We selected 5 and 30 wt% MEA (mono-ethanolamine) solutions to rapidly make a carbonate and Ca(OH)2 slurry. In all of the experiments, normal temperature and pressure conditions were maintained (except during desorption to check for residual CO2 in the MEA solution). Consequently, most of the CO2 was converted to carbonate. The MEA converted CO2 to ionic CO2 and rapidly created calcium carbonate. Also the formed solids that were observed were determined to be CaCO3 and Ca(OH)2 by X-ray diffractometry. Also, the MEA solution could be reused to absorb CO2. Therefore, we have confirmed the development of our suggested CCS process. This process has the ability not only to reuse emitted CO2, but it can also be employed to reuse construction wastes that include heavy metals. - Highlights: • We propose novel CO2 conversion technology by utilizing an amine solution. • In this study, alkaline solutions were used to produce CO2 precipitate. • The MEA (mono-ethanolamine) solution has a sufficient potential to fix CO2 with metal sources under moderate condition. • Also, the Ca(OH)2 slurry yielded enough Ca2+ ions to make carbonate

  14. Comparison of Surface and Column Variations of CO2 Over Urban Areas for Future Active Remote CO2 Sensors

    Science.gov (United States)

    Choi, Yonghoon; Yang, Melissa; Kooi, Susan; Browell, Edward

    2015-01-01

    High resolution in-situ CO2 measurements were recorded onboard the NASA P-3B during the DISCOVER-AQ (Deriving Information on Surface Conditions from Column and Vertically Resolved Observations Relevant to Air Quality) Field Campaign, to investigate the ability of space-based observations to accurately assess near surface conditions related to air quality. This campaign includes, Washington DC/Baltimore, MD (July 2011), San Joaquin Valley, CA (January - February 2013), Houston, TX (September 2013), and Denver, CO (July-August 2014). Each of these campaigns consisted of missed approaches and approximately two hundred vertical soundings of CO2 within the lower troposphere (surface to about 5 km). In this study, surface (0 - 1 km) and column-averaged (0 - 3.5 km) CO2 mixing ratio values from the vertical soundings in the four geographically different urban areas are used to investigate the temporal and spatial variability of CO2 within the different urban atmospheric emission environments. Tracers such as CO, CH2O, NOx, and NMHCs are used to identify the source of CO2 variations in the urban sites. Additionally, we apply nominal CO2 column weighting functions for potential future active remote CO2 sensors operating in the 1.57-microns and 2.05-microns measurement regions to convert the in situ CO2 vertical mixing ratio profiles to variations in CO2 column optical depths, which is what the active remote sensors actually measure. Using statistics calculated from the optical depths at each urban site measured during the DISCOVER-AQ field campaign and for each nominal weighting function, we investigate the natural variability of CO2 columns in the lower troposphere; relate the CO2 column variability to the urban surface emissions; and show the measurement requirements for the future ASCENDS (Active Sensing of CO2 Emissions over Nights, Days, and Seasons) in the continental U.S. urban areas.

  15. Differences between trends in atmospheric CO2 and the reported trends in anthropogenic CO2 emissions

    International Nuclear Information System (INIS)

    Averaged annual accumulation of CO2 in the atmosphere, dCa/dt, has been slowing from peak growth in 2002/2003 associated with anomalous climate-induced emissions at high northern latitudes. This slowing is widespread but determined with greatest certainty in the largest well-mixed portion of the global troposphere (30 deg S-90 deg S). We rely on atmospheric mixing for global integration and selection of atmospheric data for spatial representativeness. Prior to 2002/2003, after empirical adjustment for perturbations associated with ENSO and volcanic activity (EV), dCa/dt increases are well represented by linear regression, using direct monitoring records from 1990 or 1965, also from pre-industrial times using archived air. In contrast, modelled atmospheric trends due to reported emissions dCE/dt (assuming historically consistent oceanic and terrestrial uptake mechanisms), agree with dCa/dt or dCa/dt-EV up until 1990, are near-stable through the 1990s and increase by 29% between 2000 and 2008. Using atmospheric constraints based on trends in both dCa/dt-EV and interhemispheric gradient, the differences between trends in dCE/dt and atmospheric CO2 growth are most simply explained as an artefact of underestimating 1994-2003 emissions by around 6%. This is achieved with a near constant post-1965 airborne fraction; otherwise unusually complicated sink changes are required for the period.

  16. Ranking with Submodular Valuations

    CERN Document Server

    Azar, Yossi

    2010-01-01

    We study the problem of ranking with submodular valuations. An instance of this problem consists of a ground set $[m]$, and a collection of $n$ monotone submodular set functions $f^1, \\ldots, f^n$, where each $f^i: 2^{[m]} \\to R_+$. An additional ingredient of the input is a weight vector $w \\in R_+^n$. The objective is to find a linear ordering of the ground set elements that minimizes the weighted cover time of the functions. The cover time of a function is the minimal number of elements in the prefix of the linear ordering that form a set whose corresponding function value is greater than a unit threshold value. Our main contribution is an $O(\\ln(1 / \\epsilon))$-approximation algorithm for the problem, where $\\epsilon$ is the smallest non-zero marginal value that any function may gain from some element. Our algorithm orders the elements using an adaptive residual updates scheme, which may be of independent interest. We also prove that the problem is $\\Omega(\\ln(1 / \\epsilon))$-hard to approximate, unless P...

  17. Biofilm enhanced subsurface sequestration of supercritical CO2

    Science.gov (United States)

    Mitchell, A. C.; Phillips, A.; Hiebert, R.; Gerlach, R.; Kaszuba, J.; Cunningham, A.

    2007-12-01

    In order to develop subsurface CO2 storage as a viable engineered mechanism to reduce concentrations of atmospheric CO2, any potential ¡°leakage¡± of injected supercritical CO2 (scCO2) from the ground to the atmosphere must be reduced. Here, we investigate the utility of biofilms, which are microorganism assemblages firmly attached to a surface, as a means of reducing scCO2 leakage. Firstly, experiments were performed to test whether biofilms were more resilient than planctonic cells to scCO2. Bacillus mojavensis biofilms were grown on a sand support matrix in scCO2 extractor cartridges at 30°C. B. mojavensis was also grown under suspended planctonic conditions in the same media overnight and aliquots were decanted into scCO2 extractor cartridges. Biofilm and suspended B. mojavensis samples were processed on a Supercritical Fluid Extractor with pressurization to 2000 psi at 35°C, and a 20 minute flow of scCO2. Suspended growth samples revealed a 3 log reduction in cell viability while biofilm only showed a 1 log reduction, demonstrating that B. mojavensis biofilms are more resilient than planctonic cells to scCO2. Protective extra cellular polymeric substances which make up the biofilm matrix likely provide a protective barrier against scCO2. Secondly, the ability of biofilms to grow under high pressure and reduce the permeability of porous geological matrices was investigated using a unique high pressure (8.9MPa), moderate temperature (¡Ý 32°C) flow reactor containing 40 millidarcy Berea sandstone cores. The flow reactor was inoculated with the biofilm forming organism Shewanella fridgidimarina. Electron microscopy of the rock core revealed substantial biofilm accumulation in rock pores which resulted in core permeability. Permeability did not increase in response to starvation and scCO2 challenges. Viable population assays of organisms in the effluent indicated survival of the microorganisms following scCO2 challenges of <71h and starvation for <363h

  18. Uncertainty Quantification for CO2-Enhanced Oil Recovery

    Science.gov (United States)

    Dai, Z.; Middleton, R.; Bauman, J.; Viswanathan, H.; Fessenden-Rahn, J.; Pawar, R.; Lee, S.

    2013-12-01

    CO2-Enhanced Oil Recovery (EOR) is currently an option for permanently sequestering CO2 in oil reservoirs while increasing oil/gas productions economically. In this study we have developed a framework for understanding CO2 storage potential within an EOR-sequestration environment at the Farnsworth Unit of the Anadarko Basin in northern Texas. By coupling a EOR tool--SENSOR (CEI, 2011) with a uncertainty quantification tool PSUADE (Tong, 2011), we conduct an integrated Monte Carlo simulation of water, oil/gas components and CO2 flow and reactive transport in the heterogeneous Morrow formation to identify the key controlling processes and optimal parameters for CO2 sequestration and EOR. A global sensitivity and response surface analysis are conducted with PSUADE to build numerically the relationship among CO2 injectivity, oil/gas production, reservoir parameters and distance between injection and production wells. The results indicate that the reservoir permeability and porosity are the key parameters to control the CO2 injection, oil and gas (CH4) recovery rates. The distance between the injection and production wells has large impact on oil and gas recovery and net CO2 injection rates. The CO2 injectivity increases with the increasing reservoir permeability and porosity. The distance between injection and production wells is the key parameter for designing an EOR pattern (such as a five (or nine)-spot pattern). The optimal distance for a five-spot-pattern EOR in this site is estimated from the response surface analysis to be around 400 meters. Next, we are building the machinery into our risk assessment framework CO2-PENS to utilize these response surfaces and evaluate the operation risk for CO2 sequestration and EOR at this site.

  19. 5% CO2 is a potent, fast acting inhalation anticonvulsant

    Science.gov (United States)

    Tolner, Else A.; Hochman, Daryl W.; Hassinen, Pekka; Otáhal, Jakub; Gaily, Eija; Haglund, Michael M.; Kubová, Hana; Schuchmann, Sebastian; Vanhatalo, Sampsa; Kaila, Kai

    2010-01-01

    Purpose CO2 has been long recognized for its anticonvulsant properties. We aimed to determine whether inhaling 5% CO2 can be used to suppress seizures in epilepsy patients. The effect of CO2 on cortical epileptic activity accompanying behavioral seizures was studied in rats and a non-human primate and based on these data, preliminary tests were carried out in humans. Methods In freely moving rats, cortical afterdischarges paralleled by myoclonic convulsions were evoked by sensorimotor cortex stimulation. 5% CO2 was applied for 5 minutes, 3 minutes before stimulation. In macaque monkeys, hypercarbia was induced by hypoventilation while seizure activity was electrically or chemically evoked in the sensorimotor cortex. Seven patients with drug-resistant partial epilepsy were examined with video-EEG and received 5% CO2 in medical carbogen shortly after electrographic seizure onset. Results In rats, 5% CO2 strongly suppressed cortical afterdischarges, by ca. 75%, while responses to single-pulse stimulation were reduced by about 15% only. In macaques, increasing pCO2 from 37 to 44-45 mmHg (corresponding to inhalation of 5% CO2 or less) suppressed stimulation-induced cortical afterdischarges by about 70% and single, bicuculline-induced epileptiform spikes by ca. 25%. In a pilot trial carried out in 7 patients, a rapid termination of electrographic seizures was seen despite the fact that the application of 5% CO2 was started after seizure generalization. Conclusions 5% CO2 has a fast and potent anticonvulsant action. The present data suggest that medical carbogen with 5% CO2 can be used for acute treatment to suppress seizures in epilepsy patients. PMID:20887367

  20. Buoyancy-driven CO2/brine flow at reservoir conditions

    Science.gov (United States)

    Oh, J.; Kim, K.; Han, W.; Kim, T.; Kim, J.; Park, E.

    2013-12-01

    Suitable geological formations should guarantee a long-term safe and reliable storage of the injected supercritical CO2. In this study we targeted the cases of gravity-driven CO2 plume migration in a storage formation and the resulting CO2 leakage to overlying formation through a possible fractures or abandoned wells. A laboratory experiment and numerical model for two-phase core-flooding tests were designed to understand the buoyancy effect on supercritical CO2 migration under reservoir conditions. A series of core flooding tests were performed with Berea sandstone cores which have 20 % porosity and 1.7×10-13 m2 permeability. Unlike the normal core-flooding tests, the core was set up in a vertical direction and the CO2 was released at the bottom of the core to investigate the gravity effect on CO2 migration. During the test, the downstream pressure was maintained at 10 MPa, and the confining pressure was kept at 20 MPa. The temperature was set to be 40 °C to reflect the 1 km subsurface environment. The CO2-flooding (drainage) tests with brine-saturated core were performed with various CO2-release periods. The CO2 saturation was measured with a linear X-ray scanner. In addition to laboratory experiments, numerical simulations were performed to provide further insight into the CO2 migration behavior. TOUGH2 with ECO2N module was used to simulate CO2/brine core-flooding tests. Dimensionless numbers (Capillary number and Bond number) were calculated with the simulation results at various time points covering both the release and monitoring period.

  1. TG-FTIR measurement of CO2-H2O co-adsorption for CO2 air capture sorbent screening

    OpenAIRE

    Smal, I.M.; Yu, Q; Veneman, R.; Fränzel-Luiten, B.; Brilman, D.W.F.

    2014-01-01

    Capturing atmospheric CO2 using solid sorbents is gaining interest. As ambient air normally contains much more (up to 100 times) water than CO2, a selective sorbent is desirable as co-adsorption will most likely occur. In this study, a convenient method based on an TG-FTIR analysis system is developed and used to characterize sorbents for their water and CO2 adsorption capacity when exposed to ambient air. The method allows to determine quantitatively the co-adsorbed amounts of CO2 and water ...

  2. Ab initio studies on [bmim][PF6]–CO2 mixture and CO2 clusters

    Indian Academy of Sciences (India)

    B L Bhargava; M Saharay; S Balasubramanian

    2008-06-01

    Ab initio molecular dynamics studies have been carried out on the room temperature ionic liquid, 1,n-butyl,3-methylimidazolium hexafluorophosphate ([bmim][PF6]) and supercritical carbon dioxide mixture at room temperature and experimental density. Partial radial distribution functions (RDF) for different sites have been computed to see the organization of CO2 molecules around the ionic liquid. Several partial RDFs around the carbon atom of CO2 molecule are compared to find out that the CO2 has specific interaction with a carbon atom present in the imidazolium ring. The CO2 is also found to be very well organized around the terminal carbon atom of the butyl chain. The partial RDFs for the oxygen atoms around oxygen and carbon atoms of the CO2 suggests that there is very good organization of CO2 molecules around themselves even in the [bmim][PF6] – CO2 mixture. The instantaneous quadrupole moment tensor has been calculated for the anion and the cation. The ensemble average of diagonal components of quadrupole moment tensor of the cation have finite values, whereas the off-diagonal components of the cation and both the diagonal and off-diagonal components of the anion have the value of zero with a large standard deviation. The CPMD studies performed on CO2 clusters reveals the greater tendency of the clusters with more CO2 units, to deviate from the linear geometry.

  3. Photosynthetic responses to elevated CO2 and O3 in Quercus ilex leaves at a natural CO2 spring

    International Nuclear Information System (INIS)

    Photosynthetic stimulation and stomatal conductance (Gs) depression in Quercus ilex leaves at a CO2 spring suggested no down-regulation. The insensitivity of Gs to a CO2 increase (from ambient 1500 to 2000 μmol mol-1) suggested stomatal acclimation. Both responses are likely adaptations to the special environment of CO2 springs. At the CO2-enriched site, not at the control site, photosynthesis decreased 9% in leaves exposed to 2x ambient O3 concentrations in branch enclosures, compared to controls in charcoal-filtered air. The stomatal density reduction at high CO2 was one-third lower than the concomitant Gs reduction, so that the O3 uptake per single stoma was lower than at ambient CO2. No significant variation in monoterpene emission was measured. Higher trichome and mesophyll density were recorded at the CO2-enriched site, accounting for lower O3 sensitivity. A long-term exposure to H2S, reflected by higher foliar S-content, and CO2 might depress the antioxidant capacity of leaves close to the vent and increase their O3 sensitivity. - Very high CO2 concentrations did not compensate for the effects of O3 on holm oak photosynthesis

  4. IMPACT OF CO2 ENHANCEMENT ON PHOTOSYNTHESIS AND PROTEIN PROFILE -RESPONSE STUDIES WITH A CO2 RESPONSIVE BLACK GRAM GENOTYPE

    Directory of Open Access Journals (Sweden)

    P. Sathish

    2014-09-01

    Full Text Available Black gram (Vigna mungo (L. Hepper var. IC-282009 - a highly CO2 responsive genotype for biomass and seed yield was grown in Open top chambers (OTCs under three levels of CO2 i.e. ambient (390 ppm and two elevated levels 550ppm and 700ppm to assess photosynthetic acclimation to elevated CO2. Net photosynthetic rate (PN, change in leaf soluble protein profile and leaf carbohydrate constituents such as total soluble sugars, reducing sugars and starch content in leaves was quantified at all three CO2 concentrations. Photosynthetic rate was enhanced by 78% and 30% at flowering stage with 550ppm and 700ppm CO2 as compared with ambient control. It was also observed a higher accumulation of starch, total soluble sugars and reducing sugars in leaves at elevated CO2 levels. However, the leaf protein content recorded a decrease and altered the profile of ploy peptides with enhanced CO2 levels. At elevated CO2 concentrations significant differences were observed in ploy peptide profile at vegetative and flowering stages, the intensity of 260 kDa poly peptide increased at vegetative stage, whereas 72 kDa polypeptide increased at flowering stage, while 52 kDa poly peptide decreased at both stages. Enhanced CO2 concentrations improved the PN though certain polypeptides of leaf protein are down regulated and necessitate further experimentation to confirm their involvement in responsiveness of the selected black gram genotype

  5. Consistent ranking of volatility models

    DEFF Research Database (Denmark)

    Hansen, Peter Reinhard; Lunde, Asger

    2006-01-01

    We show that the empirical ranking of volatility models can be inconsistent for the true ranking if the evaluation is based on a proxy for the population measure of volatility. For example, the substitution of a squared return for the conditional variance in the evaluation of ARCH-type models can...

  6. University Rankings in Critical Perspective

    Science.gov (United States)

    Pusser, Brian; Marginson, Simon

    2013-01-01

    This article addresses global postsecondary ranking systems by using critical-theoretical perspectives on power. This research suggests rankings are at once a useful lens for studying power in higher education and an important instrument for the exercise of power in service of dominant norms in global higher education. (Contains 1 table and 1…

  7. Obsession with Rankings Goes Global

    Science.gov (United States)

    Labi, Aisha

    2008-01-01

    A Chinese list of the world's top universities would seem an unlikely concern for French politicians. But this year, France's legislature took aim at the annual rankings produced by Shanghai Jiao Tong University, which claims to list the 500 best universities in the world. The highest-ranked French entry, Universite Pierre et Marie Curie, comes in…

  8. PETROCHINA TOPS ASIAN COMPETITIVENESS RANKING

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    PetroChina, the largest oil producer in China, ranks first in a competitiveness report of listed Asian enterprises recently published by the Research Institute of Boao Forum for Asia. The oil giant tops the ranks in the Asian Competitiveness: Annual Repor

  9. Science-based permitting of geological sequestration of CO2 in brine reservoirs in the U.S

    International Nuclear Information System (INIS)

    We present a science-based approach to the regulation and permitting of CO2 sequestration activities. Any such regulatory scheme should address both operational (or short-term) issues and the long-term goals of geological sequestration of CO2. In the United States many of the key operational issues, such as permitting injection wells and CO2 pipelines, are reasonably well addressed in current Federal- and State-based rules and legislation. The long-term, overarching goal of sequestration projects of decreasing the rate of increase in atmospheric concentrations of CO2 is not addressed by current regulations. We propose a hierarchical approach, in which the State/Federal government is responsible for developing regional assessments that result in broad regions of brine reservoirs being rated as 'sequestration ready' (and designated in this paper as general permits). The burden faced by an applicant in permitting an injection site should be considerably less if the general area of the chosen site has been ranked favorably. Such a phased, hierarchical permitting process would be helpful in addressing public and stakeholder concerns related to the impact and safety of geological sequestration operations. It will also build in coordination between neighboring injection sites, where interferences are likely because of the large amount of CO2 to be injected

  10. The potential of geological storage of CO2 in Austria: a techno-economic assessment

    Science.gov (United States)

    Brüstle, Anna Katharina; Welkenhuysen, Kris; Bottig, Magdalena; Piessens, Kris; Ramirez, Andrea; Swenner, Rudy

    2014-05-01

    economic uncertainties. Results indicate a significant potential for CCS in Austria and a very high probability for any CO2 storage activity. The assessment of the average practical capacity of the whole country is 120Mt at 15€/tCO2 of storage budget, while the average matched national capacity is 40Mt. Concerning the individual reservoirs, reservoir development probabilities generally lie between 20 and 30%. These numbers served as basis for a reservoir exploration ranking. Compared to current emissions, total storage capacity is at the low end, which is likely the main technical limiting factor for CCS deployment in Austria. Also, current policy seems not in favour of CCS. Storage capacity is however high enough to provide a significant contribution to the reduction of CO2 emissions in the country, in the order of a few million tonnes per year. Opportunities to combine CO2 geological storage and geothermal energy seem promising, but require additional evaluation. Welkenhuysen, K., Ramirez, A., Swennen, R. & Piessens, K., 2013. Ranking potential CO2 storage reservoirs: an exploration priority list for Belgium. International Journal of Greenhouse Gas Control, 17, p. 431-449

  11. Costs, safety and uncertainties of CO2 infrastructure development

    NARCIS (Netherlands)

    Knoope, M.M.J.

    2015-01-01

    To avoid drastic climate change, strong reductions in CO2 emissions are required. Carbon capture and storage (CCS) is a potential mitigation measure. With CCS, CO2 from industrial and energy related sources is captured from flue gases and subsequently transported with pipelines and / or ships to geo

  12. Target atmospheric CO2: Where should humanity aim?

    CERN Document Server

    Hansen, J; Kharecha, P; Beerling, D; Masson-Delmotte, V; Pagani, M; Raymo, M; Royer, D L; Zachos, J C

    2008-01-01

    Paleoclimate data show that climate sensitivity is ~3 deg-C for doubled CO2, including only fast feedback processes. Equilibrium sensitivity, including slower surface albedo feedbacks, is ~6 deg-C for doubled CO2 for the range of climate states between glacial conditions and ice-free Antarctica. Decreasing CO2 was the main cause of a cooling trend that began 50 million years ago, large scale glaciation occurring when CO2 fell to 425 +/- 75 ppm, a level that will be exceeded within decades, barring prompt policy changes. If humanity wishes to preserve a planet similar to that on which civilization developed and to which life on Earth is adapted, paleoclimate evidence and ongoing climate change suggest that CO2 will need to be reduced from its current 385 ppm to at most 350 ppm. The largest uncertainty in the target arises from possible changes of non-CO2 forcings. An initial 350 ppm CO2 target may be achievable by phasing out coal use except where CO2 is captured and adopting agricultural and forestry practice...

  13. Multiple timescales for neutralization of fossil fuel CO2

    Science.gov (United States)

    Archer, David; Kheshgi, Haroon; Maier-Reimer, Ernst

    The long term abiological sinks for anthropogenic CO2 will be dissolution in the oceans and chemical neutralization by reaction with carbonates and basic igneous rocks. We use a detailed ocean/sediment carbon cycle model to simulate the response of the carbonate cycle in the ocean to a range of anthropogenic CO2 release scenarios. CaCO3 will play only a secondary role in buffering the CO2 concentration of the atmosphere because CaCO3 reaction uptake capacity and kinetics are limited by the dynamics of the ocean carbon cycle. Dissolution into ocean water sequesters 70-80% of the CO2 release on a time scale of several hundred years. Chemical neutralization of CO2 by reaction with CaCO3 on the sea floor accounts for another 9-15% decrease in the atmospheric concentration on a time scale of 5.5-6.8 kyr. Reaction with CaCO3 on land accounts for another 3-8%, with a time scale of 8.2 kyr. The final equilibrium with CaCO3 leaves 7.5-8% of the CO2 release remaining in the atmosphere. The carbonate chemistry of the oceans in contact with CaCO3 will act to buffer atmospheric CO2 at this higher concentration until the entire fossil fuel CO2 release is consumed by weathering of basic igneous rocks on a time scale of 200 kyr.

  14. Electrocatalytic CO2 conversion to oxalate by a copper complex

    NARCIS (Netherlands)

    Angamuthu, R.; Byers, P.; Lutz, M.; Spek, A.L.; Bouwman, E.

    2010-01-01

    Global warming concern has dramatically increased interest in using CO2 as a feedstock for preparation of value-added compounds, thereby helping to reduce its atmospheric concentration. Here, we describe a dinuclear copper(I) complex that is oxidized in air by CO2 rather than O2; the product is a te

  15. New methodologies for integrating algae with CO2 capture

    NARCIS (Netherlands)

    Hernandez Mireles, I.; Stel, R.W. van der; Goetheer, E.L.V.

    2014-01-01

    It is generally recognized, that algae could be an interesting option for reducing CO2 emissions. Based on light and CO2, algae can be used for the production various economically interesting products. Current algae cultivation techniques, however, still present a number of limitations. Efficient fe

  16. CO2 dissolution and its impact on reservoir pressure behavior

    NARCIS (Netherlands)

    Peters, E.; Egberts, P.J.P.; Loeve, D.; Hofstee, C.

    2015-01-01

    Geological storage of CO2 in large, saline aquifers needs to be monitored for safety purposes. In particular the observation of the pressure behavior of a storage site is relevant for the indication of CO2 leakage. However, interpretation of observed pressure is not straightforward in these systems,

  17. CO2-Philic polymer membrane with extremely high separation performance

    KAUST Repository

    Yave, Wilfredo

    2010-01-12

    Polymeric membranes are attractive for CO2 separation and concentration from different gas streams because of their versatility and energy efficiency; they can compete with, and they may even replace, traditional absorption processes. Here we describe a simple and powerful method for developing nanostructured and CO2-philic polymer membranes for CO2 separation. A poly(ethylene oxide)-poly(butylene terephthalate) multiblock copolymer is used as membrane material. Smart additives such as polyethylene glycol dibutyl ether are incorporated as spacers or fillers for producing nanostructured materials. The addition of these specific additives produces CO2-philic membranes and increases the CO2 permeability (750 barrer) up to five-fold without the loss of selectivity. The membranes present outstanding performance for CO2 separation, and the measured CO2 flux is extremely high ( > 2 m3 m -2 h-1 bar-1) with selectivity over H2 and N2 of 10 and 40, respectively, making them attractive for CO 2 capture. © 2009 American Chemical Society.

  18. Study of shale wettability for CO2 storage

    NARCIS (Netherlands)

    Shojai Kaveh, N.; Barnhoorn, A.; Schoemaker, F.C.; Wolf, K.H.A.A.

    2015-01-01

    For a water-saturated cap-rock, which consists of a low-permeability porous material, the wettability of the reservoir rock-connate water- CO2 system and the interfacial tension (IFT) between CO2 and connate water are the significant parameters for the evaluation of the capillary sealing. Also, the

  19. The oil market and international agreements on CO2 emissions

    International Nuclear Information System (INIS)

    In order to avoid a relatively large risk of dramatic adverse climatic changes during the next century, greenhouse gas emissions must be reduced significantly relative to present emissions. CO2 is the most important greenhouse gas, so any international agreement will certainly cover CO2 emissions. Any international agreement to reduce emissions of CO2 is going to have a significant impact on the markets for fossil fuels. The analysis shows that is not only the amount of CO2 emissions permitted in an agreement which matters for fossil fuel prices, but also the type of agreement. Two obvious forms of agreements, which under certain assumptions both are cost efficient, are (a) tradeable emission permits, and (b) an international CO2 tax. If the fossil fuel markets were perfectly competitive, these two types of agreements would have the same effect on the producer price of fossil fuels. However, fossil fuel markets are not completely competitive. It is shown that, under imperfect competition, direct regulation of the ''tradeable quotas'' type tends to imply higher producer prices than an international CO2 tax giving the same total CO2 emissions. A numerical illustration of the oil market indicates that the difference in producer prices for the two types of CO2 agreements is quite significant. 6 refs., 2 figs., 1 tab

  20. FINGER - PULSE VOLUME DURING CO2 INDUCED PANIC STATES

    OpenAIRE

    Bharathy, P.; Sembulingam, Prema; Sembulingam, K.; Srinivasan, T.N.; Namasivayam, A

    1992-01-01

    Changes in Fingure-Pulse Volume (FPV) during CO2 inhalation were studied in patients diagnosed as having Anxiety disorder with history of panic attacks. Waxing and Waning of the FPV was observed in all the cases after CO2 inhalation, and this pattern was significantly intensified during panic attacks during the study. The significance and the mechanism underlying the same is discussed.