Powered by Deep Web Technologies
Note: This page contains sample records for the topic "determination modeling carbon" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


1

Low Cost Carbon Fiber Production Carbon Fiber Manufacturing Cost Modeling  

E-Print Network (OSTI)

Low Cost Carbon Fiber Production Carbon Fiber Manufacturing Cost Modeling Oak Ridge National been identified by carbon fiber manufacturers as a market with substantial growth potential. When manufactured with carbon fiber as opposed to traditional materials such as steel, automotive parts are able

2

Modelling the carbon system  

E-Print Network (OSTI)

ABSTRACT. Claims that forest cutting (luring the last few decades has contributed significantly to the buildup in atmospheric CO2 have cast doubt on the validity of models used to estimate CO. uptake by the ocean. In this paper we review the existing models and conclude that the box-diffusion model of Oeschger and his co-workers provides an excellent fit to the average distributions of natural and bomb-produced radiocarbon. We also take the first steps toward a more detailed ocean model which takes into account upwelling in the equatorial zone and deep water formation in the polar zone. The model is calibrated using the distribution of bomb-produced and cosmic ray-produced radiocarbon in the ocean. Preliminary calculations indicate that the fossil fuel CO2 uptake by this model will be greater than that by the box-diffusion model of Oeschger and others (1975) but not great enough to accommodate a significant decline in the mass of the terrestrial biosphere over the past two decades.

Wallace S Broecker; Tsung-hung Peng; Richard Engh

1980-01-01T23:59:59.000Z

3

Evaluation of Different Soil Carbon Determination Methods  

SciTech Connect

Determining soil carbon (C) with high precision is an essential requisite for the success of the terrestrial C sequestration program. The informed choice of management practices for different terrestrial ecosystems rests upon accurately measuring the potential for C sequestration. Numerous methods are available for assessing soil C. Chemical analysis of field-collected samples using a dry combustion method is regarded as the standard method. However, conventional sampling of soil and their subsequent chemical analysis is expensive and time consuming. Furthermore, these methods are not sufficiently sensitive to identify small changes over time in response to alterations inmanagement practices or changes in land use. Presently, several different in situ analytic methods are being developed purportedly offering increased accuracy, precision and cost-effectiveness over traditional ex situ methods. We consider that, at this stage, a comparative discussion of different soil C determination methods will improve the understanding needed to develop a standard protocol.

Chatterjee, Dr Amitava [Ohio State University; Lal, Dr R [Ohio State University; Wielopolski, Dr L [Brookhaven National Laboratory (BNL); Martin, Madhavi Z [ORNL; Ebinger, Dr Michael H [Los Alamos National Laboratory (LANL)

2009-01-01T23:59:59.000Z

4

Modeling shallow marine carbonate depositional systems  

Science Conference Proceedings (OSTI)

Geological Process Models (GPMs) have been used in the past to simulate the distinctive stratigraphies formed in carbonate sediments, and to explore the interaction of controls that produce heterogeneity. Previous GPMs have only indirectly included the ... Keywords: Carbonate, Geological process model, Numerical modeling, Reef, Supersaturation

Jon Hill; Daniel Tetzlaff; Andrew Curtis; Rachel Wood

2009-09-01T23:59:59.000Z

5

Modeling Carbon Concentration Profiles in Austenitic Stainless ...  

Science Conference Proceedings (OSTI)

Presentation Title, Modeling Carbon Concentration Profiles in Austenitic Stainless Steels Carburized at Low Temperatures. Author(s), Gary M. Michal, Xiaoting ...

6

Determination of Total Petroleum Hydrocarbons (TPH) Using Total Carbon Analysis  

SciTech Connect

Several methods have been proposed to replace the Freon(TM)-extraction method to determine total petroleum hydrocarbon (TPH) content. For reasons of cost, sensitivity, precision, or simplicity, none of the replacement methods are feasible for analysis of radioactive samples at our facility. We have developed a method to measure total petroleum hydrocarbon content in aqueous sample matrixes using total organic carbon (total carbon) determination. The total carbon content (TC1) of the sample is measured using a total organic carbon analyzer. The sample is then contacted with a small volume of non-pokar solvent to extract the total petroleum hydrocarbons. The total carbon content of the resultant aqueous phase of the extracted sample (TC2) is measured. Total petroleum hydrocarbon content is calculated (TPH = TC1-TC2). The resultant data are consistent with results obtained using Freon(TM) extraction followed by infrared absorbance.

Ekechukwu, A.A.

2002-05-10T23:59:59.000Z

7

Modelling Correlation in Carbon and Energy Markets  

E-Print Network (OSTI)

, reflecting usage of installed generation capacity. The two hydrocarbon fuels, whose price interactions with carbon emission allowances are under consideration in this study, natural gas and hard coal, together account for approximately 35% of total fuel input... Modelling Correlation in Carbon and Energy Markets Philipp Koenig February 2011 CWPE 1123 & EPRG 1107 www.eprg.group.cam.ac.uk E P R G W O R K IN G P A P E R Abstract Modelling Correlation...

Koenig, Philipp

2011-02-10T23:59:59.000Z

8

Workshop on Carbon Sequestration Science - Modeling and Integrated Assessment  

NLE Websites -- All DOE Office Websites (Extended Search)

Modeling and Integrated Modeling and Integrated Assessment Howard Herzog MIT Energy Laboratory May 24, 2001 Economic Assessments * Engineering analysis of CO 2 separation and capture * Economic modeling/ integrated assessment of carbon capture and sequestration * Comparison on equal basis of the major sequestration options Economic Modeling Motivation * When might carbon capture and sequestration (CCS) become competitive? * What is its potential scale? * Which technologies look most promising? . . . . And when? * How to see the potential in a general market context? Detailed Reference *Sean Biggs Thesis: S Biggs, S. D., "Sequestering Carbon from Power Plants: The Jury is Still Out," M.I.T. Masters Thesis, (2000). S http://sequestration.mit.edu/pdf/SeanBiggs.pdf What Determines Competitiveness?

9

Determination of optimum electrolyte composition for molten carbonate fuel cells  

DOE Green Energy (OSTI)

The objective of this study is to determine the optimum electrolyte composition for molten carbonate fuel cells. To accomplish this, the contractor will provide: (1) Comprehensive reports of on-going efforts to optimize carbonate composition. (2) A list of characteristics affected by electrolyte composition variations (e.g. ionic conductivity, vapor pressure, melting range, gas solubility, exchange current densities on NiO, corrosion and cathode dissolution effects). (3) Assessment of the overall effects that these characteristics have on state-of-the-art cell voltage and lifetime.

Yuh, C.Y.; Pigeaud, A.

1987-01-01T23:59:59.000Z

10

Multiscale modeling with carbon nanotubes  

Science Conference Proceedings (OSTI)

Technologically important nanomaterials come in all shapes and sizes. They can range from small molecules to complex composites and mixtures. Depending upon the spatial dimensions of the system and properties under investigation computer modeling of ... Keywords: DFT (density functional theory), Mesoscale modeling, Molecular modeling, NEGF (nonequilibrium Green's function), NEMS (nanoelectromechanical sensors), Nanocomposites, Nanotubes, Sensors

Amitesh Maiti

2008-02-01T23:59:59.000Z

11

Soil Carbon Modeling (Mac Post) A. Rothamsted model carbon pools and processes. Their approximate equivalents for the EBIS sample processing  

E-Print Network (OSTI)

Soil Carbon Modeling (Mac Post) A. Rothamsted model carbon pools and processes. Their approximate' soil horizon show that model improvements need to be made to capture observed soil carbon cycling and transport processes. Testing and improvement of soil carbon cycling models is a key anticipated output

12

Fiber Bridging Model for Reinforced-Carbon-Carbon  

Science Conference Proceedings (OSTI)

Symposium, Professor K. K. Chawla Honorary Symposium on Fibers, Foams and ... fiber bridging and resistance-curve behavior in reinforced-carbon-carbon (

13

3D Modelling of Carbon Allotropes Used in Nanotechnology  

Science Conference Proceedings (OSTI)

Graphene, Carbon nanoribbons, Carbon nanotubes and Fullerene (Buckyball) are allotropes of carbon which are widely used in Nanotechnology research due to their remarkable properties. Electrical and mechanical properties of those allotropes vary with ... Keywords: Graphene, Carbon nanoribbons, Carbon nanotubes, Fullerines, 3D modelling, java3D

M. R. M. Mufthas; C. S. Rupasinghe

2010-05-01T23:59:59.000Z

14

Nonlinear texture modeling of mesophase carbon fibers  

Science Conference Proceedings (OSTI)

This paper presents a theoretical and computational nonlinear study of structure selection in carbon fibers obtained by spinning binary blends of carbonaceous mesophases precursors. Although models for single component mesophase precursors seem to capture ... Keywords: carbonaceous mesophase, multiple solution, nematic liquid crystals, texture

M. Golmohammadi; A. D. Rey

2007-05-01T23:59:59.000Z

15

Theoretical Model for Nanoporous Carbon Supercapacitors  

Science Conference Proceedings (OSTI)

The unprecedented anomalous increase in capacitance of nanoporous carbon supercapacitors at pore sizes smaller than 1 nm [Science 2006, 313, 1760.] challenges the long-held presumption that pores smaller than the size of solvated electrolyte ions do not contribute to energy storage. We propose a heuristic model to replace the commonly used model for an electric double-layer capacitor (EDLC) on the basis of an electric double-cylinder capacitor (EDCC) for mesopores (2 {50 nm pore size), which becomes an electric wire-in-cylinder capacitor (EWCC) for micropores (supercapacitor properties to be correlated with pore size, specific surface area, Debye length, electrolyte concentration and dielectric constant, and solute ion size. The new model not only explains the experimental data, but also offers a practical direction for the optimization of the properties of carbon supercapacitors through experiments.

Sumpter, Bobby G [ORNL; Meunier, Vincent [ORNL; Huang, Jingsong [ORNL

2008-01-01T23:59:59.000Z

16

Parallel Computing for Terrestrial Ecosystem Carbon Modeling  

Science Conference Proceedings (OSTI)

Terrestrial ecosystems are a primary component of research on global environmental change. Observational and modeling research on terrestrial ecosystems at the global scale, however, has lagged behind their counterparts for oceanic and atmospheric systems, largely because the unique challenges associated with the tremendous diversity and complexity of terrestrial ecosystems. There are 8 major types of terrestrial ecosystem: tropical rain forest, savannas, deserts, temperate grassland, deciduous forest, coniferous forest, tundra, and chaparral. The carbon cycle is an important mechanism in the coupling of terrestrial ecosystems with climate through biological fluxes of CO{sub 2}. The influence of terrestrial ecosystems on atmospheric CO{sub 2} can be modeled via several means at different timescales. Important processes include plant dynamics, change in land use, as well as ecosystem biogeography. Over the past several decades, many terrestrial ecosystem models (see the 'Model developments' section) have been developed to understand the interactions between terrestrial carbon storage and CO{sub 2} concentration in the atmosphere, as well as the consequences of these interactions. Early TECMs generally adapted simple box-flow exchange models, in which photosynthetic CO{sub 2} uptake and respiratory CO{sub 2} release are simulated in an empirical manner with a small number of vegetation and soil carbon pools. Demands on kinds and amount of information required from global TECMs have grown. Recently, along with the rapid development of parallel computing, spatially explicit TECMs with detailed process based representations of carbon dynamics become attractive, because those models can readily incorporate a variety of additional ecosystem processes (such as dispersal, establishment, growth, mortality etc.) and environmental factors (such as landscape position, pest populations, disturbances, resource manipulations, etc.), and provide information to frame policy options for climate change impact analysis.

Wang, Dali [ORNL; Post, Wilfred M [ORNL; Ricciuto, Daniel M [ORNL; Berry, Michael [University of Tennessee, Knoxville (UTK)

2011-01-01T23:59:59.000Z

17

ORNL researchers improve soil carbon cycling models | ornl.gov  

NLE Websites -- All DOE Office Websites (Extended Search)

researchers improve soil carbon cycling models researchers improve soil carbon cycling models January 01, 2013 ORNL's new carbon cycling model could help scientists understand the role of soil microbes (MBC) in climate change by tracking extracellular enzymes (ENZ) that break down carbon-rich soil materials (SOC) into forms that microbes can respire (DOC). A more robust model of the soil carbon cycle developed at Oak Ridge National Laboratory (ORNL) improves understanding of carbon residence time in soils and enables scientists to make more accurate climate predictions. The model does a better job than previous models of accounting for how microbes in the soil break down carbon-rich materials and release carbon dioxide. "Soil is a big reservoir of carbon," said co-author Melanie Mayes of the Environmental Sciences Division and the Climate Change Science

18

Multiphase Sequestration Geochemistry: Model for Mineral Carbonation  

SciTech Connect

Carbonation of formation minerals converts low viscosity supercritical CO2 injected into deep saline reservoirs for geologic sequestration into an immobile form. Until recently the scientific focus of mineralization reactions with reservoir rocks has been those that follow an aqueous-mediated dissolution/precipitation mechanism, driven by the sharp reduction in pH that occurs with CO2 partitioning into the aqueous phase. For sedimentary basin formations the kinetics of aqueous-mediated dissolution/precipitation reactions are sufficiently slow to make the role of mineralization trapping insignificant over a century period. For basaltic saline formations aqueous-phase mineralization progresses at a substantially higher rate, making the role of mineralization trapping significant, if not dominant, over a century period. The overlooked mineralization reactions for both sedimentary and basaltic saline formations, however, are those that occur in liquid or supercritical CO2 phase; where, dissolved water appears to play a catalyst role in the formation of carbonate minerals. A model is proposed in this paper that describes mineral carbonation over sequestration reservoir conditions ranging from dissolved CO2 in aqueous brine to dissolved water in supercritical CO2. The model theory is based on a review of recent experiments directed at understanding the role of water in mineral carbonation reactions of interest in geologic sequestration systems occurring under low water contents.

White, Mark D.; McGrail, B. Peter; Schaef, Herbert T.; Hu, Jian Z.; Hoyt, David W.; Felmy, Andrew R.; Rosso, Kevin M.; Wurstner, Signe K.

2011-04-01T23:59:59.000Z

19

Low Carbon Development: Planning & Modelling Course | Open Energy  

Open Energy Info (EERE)

Low Carbon Development: Planning & Modelling Course Low Carbon Development: Planning & Modelling Course Jump to: navigation, search Tool Summary LAUNCH TOOL Name: Low Carbon Development: Planning & Modelling Course Agency/Company /Organization: World Bank Sector: Climate Focus Area: Renewable Energy, Economic Development, People and Policy Topics: Low emission development planning, Pathways analysis, Resource assessment Resource Type: Training materials, Workshop Website: einstitute.worldbank.org/ei/course/low-carbon-development Cost: Paid References: Low Carbon Development: Planning & Modelling[1] Program Overview This course has the following modules - (i) Introduction to Low Carbon Development Planning; (ii) Overview for Policymakers; (iii) Power; (iv) Household; (v) Transport - which introduce you to climate change

20

On the Sequential Determination of Model Misfit  

E-Print Network (OSTI)

On the Sequential Determination of Model Misfit Peter Whaite and Frank P. Ferrie TR-CIM-94-6319 Telex: 05 268510 FAX: 514 398-7348 Email: cim@cim.mcgill.ca #12;On the Sequential Determination of Model

Dudek, Gregory

Note: This page contains sample records for the topic "determination modeling carbon" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


21

Silicon Carbide Derived Carbons: Experiments and Modeling  

SciTech Connect

The main results of the computational modeling was: 1. Development of a new genealogical algorithm to generate vacancy clusters in diamond starting from monovacancies combined with energy criteria based on TBDFT energetics. The method revealed that for smaller vacancy clusters the energetically optimal shapes are compact but for larger sizes they tend to show graphitized regions. In fact smaller clusters of the size as small as 12 already show signatures of this �¢����graphitization�¢����. The modeling gives firm basis for the �¢����slit-pore�¢���� modeling of porous carbon materials and explains some of their properties. 2. We discovered small vacancy clusters and their physical characteristics that can be used to spectroscopically identify them. 3. We found low barrier pathways for vacancy migration in diamond-like materials by obtaining for the first time optimized reaction pathways.

Kertesz, Miklos [Georgetown University, Washington DC 20057

2011-02-28T23:59:59.000Z

22

Determining timescales of natural carbonation of peridotite in the Samail Ophiolite, Sultanate of Oman  

E-Print Network (OSTI)

Determining timescales of the formation and preservation of carbonate alteration products in mantle peridotite is important in order to better understand the role of this potentially important sink in the global carbon ...

Mervine, Evelyn Martinique

2012-01-01T23:59:59.000Z

23

Modelling interactions of carbon dioxide, forests, and climate  

SciTech Connect

Atmospheric carbon dioxide is rising and forests and climate is changing! This combination of fact and premise may be evaluated at a range of temporal and spatial scales with the aid of computer simulators describing the interrelationships between forest vegetation, litter and soil characteristics, and appropriate meteorological variables. Some insights on the effects of climate on the transfers of carbon and the converse effect of carbon transfer on climate are discussed as a basis for assessing the significance of feedbacks between vegetation and climate under conditions of rising atmospheric carbon dioxide. Three main classes of forest models are reviewed. These are physiologically-based models, forest succession simulators based on the JABOWA model, and ecosystem-carbon budget models that use compartment transfer rates with empirically estimated coefficients. Some regression modeling approaches are also outlined. Energy budget models applied to forests and grasslands are also reviewed. This review presents examples of forest models; a comprehensive discussion of all available models is not undertaken.

Luxmoore, R.J. [Oak Ridge National Lab., TN (United States); Baldocchi, D.D. [National Oceanic and Atmospheric Administration, Oak Ridge, TN (United States)

1994-09-01T23:59:59.000Z

24

Carbon Anode Modeling for Electric Energy Savings in  

Science Conference Proceedings (OSTI)

Presentation Title, Carbon Anode Modeling for Electric Energy Savings in the Aluminium Reduction Cell. Author(s), Dag Herman Andersen, Z. L. Zhang. On- Site ...

25

Modelling Carbon with Transferable Empirical Potentials  

Science Conference Proceedings (OSTI)

Complexities associated with hybridization and anisotropy meant that transferable potentials for carbon were slow to emerge, lagging decades behind similar ...

26

Determining Mechanical Properties of Carbon Microcoils Using Lateral Force Microscopy  

Science Conference Proceedings (OSTI)

Mechanical properties of amorphous carbon microcoil (CMC) synthesized by thermal chemical vapor deposition method were examined in compression and tension tests, using the lateral force mode of atomic force microscope (AFM). The AFM cantilever tip was ... Keywords: Atomic force microscopy (AFM), atomic force microscopy, carbon microcoil, shear modulus, spring constant

Neng-Kai Chang; Shuo-Hung Chang

2008-03-01T23:59:59.000Z

27

On the Sequential Determination of Model Misfit  

E-Print Network (OSTI)

On the Sequential Determination of Model Misfit Peter Whaite and Frank P. Ferrie TR­CIM­94) 398­6319 Telex: 05 268510 FAX: (514) 398­7348 Email: cim@cim.mcgill.ca #12; On the Sequential

Dudek, Gregory

28

Kinetic modelling of molecular hydrogen transport in microporous carbon materials.  

DOE Green Energy (OSTI)

The proposal of kinetic molecular sieving of hydrogen isotopes is explored by employing statistical rate theory methods to describe the kinetics of molecular hydrogen transport in model microporous carbon structures. A Lennard-Jones atom-atom interaction potential is utilized for the description of the interactions between H{sub 2}/D{sub 2} and the carbon framework, while the requisite partition functions describing the thermal flux of molecules through the transition state are calculated quantum mechanically in view of the low temperatures involved in the proposed kinetic molecular sieving application. Predicted kinetic isotope effects for initial passage from the gas phase into the first pore mouth are consistent with expectations from previous modeling studies, namely, that at sufficiently low temperatures and for sufficiently narrow pore mouths D{sub 2} transport is dramatically favored over H{sub 2}. However, in contrast to expectations from previous modeling, the absence of any potential barrier along the minimum energy pathway from the gas phase into the first pore mouth yields a negative temperature dependence in the predicted absolute rate coefficients - implying a negative activation energy. In pursuit of the effective activation barrier, we find that the minimum potential in the cavity is significantly higher than in the pore mouth for nanotube-shaped models, throwing into question the common assumption that passage through the pore mouths should be the rate-determining step. Our results suggest a new mechanism that, depending on the size and shape of the cavity, the thermal activation barrier may lie in the cavity rather than at the pore mouth. As a consequence, design strategies for achieving quantum-mediated kinetic molecular sieving of H{sub 2}/D{sub 2} in a microporous membrane will need, at the very least, to take careful account of cavity shape and size in addition to pore-mouth size in order to ensure that the selective step, namely passage through the pore mouth, is also the rate determining step.

Hankel, M.; Zhang, H.; Nguyen, T. X.; Bhatia, S. K.; Gray, S. K.; Smith, S. C. (Center for Nanoscale Materials); (The Univ. of Queensland)

2011-01-01T23:59:59.000Z

29

Carbon–Concentration and Carbon–Climate Feedbacks in CMIP5 Earth System Models  

Science Conference Proceedings (OSTI)

The magnitude and evolution of parameters that characterize feedbacks in the coupled carbon–climate system are compared across nine Earth system models (ESMs). The analysis is based on results from biogeochemically, radiatively, and fully coupled ...

Vivek K. Arora; George J. Boer; Pierre Friedlingstein; Michael Eby; Chris D. Jones; James R. Christian; Gordon Bonan; Laurent Bopp; Victor Brovkin; Patricia Cadule; Tomohiro Hajima; Tatiana Ilyina; Keith Lindsay; Jerry F. Tjiputra; Tongwen Wu

2013-08-01T23:59:59.000Z

30

Kinetic viscoelasticity modeling applied to degradation during carbon–carbon composite processing  

E-Print Network (OSTI)

Kinetic viscoelasticity modeling has been successfully utilized to describe phenomena during cure of thermoset based carbon fiber reinforced matrices. The basic difference from classic viscoelasticity is that the fundamental ...

Drakonakis, Vassilis M.

31

Computational mechanical modeling of the behavior of carbon nanotubes  

Science Conference Proceedings (OSTI)

This paper presents a computational method for the mechanical simulation of carbon nanotubes, whose complexity is linear on the number of atoms. The regularity of a graphene lattice at its energy ground permits the definition of a tiling scheme that ... Keywords: carbon nanotubes, computational method, mathematical modeling, molecular dynamics, numerical simulation

Maria Morandi Cecchi; Alberto Giovanni Busetto

2007-08-01T23:59:59.000Z

32

Prospective Life-Cycle Modeling of Novel Carbon Capture Materials  

NLE Websites -- All DOE Office Websites (Extended Search)

Prospective Life-Cycle Modeling of Novel Carbon Capture Materials Speaker(s): Roger Sathre Date: December 5, 2011 - 3:30pm Location: 90-4133 Seminar HostPoint of Contact: Anita...

33

A Universal Model for Nanoporous Carbon Supercapacitors Applicable to Diverse Pore Regimes, Carbons, and Electrolyte  

SciTech Connect

Supercapacitors, commonly called electric double-layer capacitors (EDLCs), are emerging as a novel type of energy storage device with the potential to substitute batteries in applications requiring high power densities. In response to the latest experimental breakthrough in nanoporous carbon supercapacitors, we propose a heuristic theoretical model that takes pore curvature into account as a replacement for the EDLC model which is based on a traditional parallel-plate capacitor. When the pore size is in the mesopore regime (2-50 nm), counterions enter mesoporous carbons and approach the pore wall to form an electric double-cylinder capacitor (EDCC); in the micropore regime (< 2 nm), solvated/desolvated counterions line up along the pore axis to form an electric wire-in-cylinder capacitor (EWCC). In the macropore regime (> 50 nm) where pores are large enough so that the pore curvature is no longer significant, the EDCC model can be reduced naturally to the EDLC model. We present density functional theory calculations and detailed analyses of available experimental data in various pore regimes, showing the significant effects of pore curvature on the supercapacitor properties of nanoporous carbons. It is shown that the EDCC/EWCC model is universal to carbon supercapacitors with diverse carbon materials including activated carbons, template carbons, and novel carbide-derived carbons, and with diverse electrolytes including organic electrolytes such as tetraethylammonium tetrafluoroborate (TEABF4), tetraethylammonium methyl-sulfonate (TEAMS) in acetonitrile, aqueous H2SO4 and KOH electrolytes, and even ionic liquid electrolyte such as 1-ethyl-3-methylimmidazolium bis(trifluromethane-sulfonyl)imide (EMI-TFSI). The EDCC/EWCC model allows the supercapacitor properties to be correlated with pore size, specific surface area, Debye length, electrolyte concentration and dielectric constant, and solute ion size, and may lend a support for the systematic optimization of the properties of carbon supercapacitors via experiments. On the basis of the insight obtained from the new model, we also discuss the effects of the kinetic solvation/desolvation process, multimodal (versus unimodal) pore size distribution, and exohedral (versus endohedral) capacitors on the electrochemical properties of supercapacitors.

Sumpter, Bobby G [ORNL; Huang, Jingsong [ORNL; Meunier, Vincent [ORNL

2008-01-01T23:59:59.000Z

34

Modeling of interface behavior in carbon nanotube composites.  

Science Conference Proceedings (OSTI)

This research focuses on the development of a constitutive model for carbon nanotube polymer composites incorporating nanoscale attributes of the interface between the nanotube and polymer. Carbon nanotube polymer composites exhibit promising properties, as structural materials and the current work will motivate improvement in their load transfer capabilities. Since separation events occur at different length and time scales, the current work also addresses the challenge of multiscale modeling in interpreting inputs at different length and time scales. The nanoscale phase separation phenomena are investigated using molecular dynamics (MD) simulations. The simulations based on MD provide grounds for developing a cohesive zone model for the interface based on laws of thermodynamics.

Hammerand, Daniel Carl; Awasthi, Amnaya P. (Texas A& M University, College Station, TX); Lagoudas, Dimitris C. (Texas A& M University, College Station, TX)

2006-05-01T23:59:59.000Z

35

Comparison of kinetic theory models of laser ablation of carbon  

SciTech Connect

The paper compares the predictions of three-dimensional kinetic theory models of laser ablation of carbon. All the models are based on the moment solution of the Boltzmann equation for arbitrary strong evaporation but use different approximations. Comparison of the model predictions demonstrated that the choice of the particular model has very little influence on the results. The influence of the heat conduction from the gas to the solid phase was also found to be negligible in this problem.

Shusser, Michael [Faculty of Mechanical Engineering, Technion, Haifa 32000 (Israel)

2010-05-15T23:59:59.000Z

36

CX-008439: Categorical Exclusion Determination | Department of...  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Exclusion Determination CX-008439: Categorical Exclusion Determination Modeling Carbon Dioxide Sequestration in Saline Aquifer and Depleted Oil Reservoir (Task 17 -...

37

CX-002613: Categorical Exclusion Determination | Department of...  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Exclusion Determination CX-002613: Categorical Exclusion Determination Modeling Carbon Dioxide Sequestration in Saline Aquifer and Depleted Oil Reservoir to Evaluate...

38

CX-002609: Categorical Exclusion Determination | Department of...  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Exclusion Determination CX-002609: Categorical Exclusion Determination Modeling Carbon Dioxide Sequestration in Saline Aquifer and Depleted Oil Reservoir to Evaluate...

39

CX-008441: Categorical Exclusion Determination | Department of...  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Exclusion Determination CX-008441: Categorical Exclusion Determination Modeling Carbon Dioxide Sequestration in Saline Aquifer and Depleted Oil Reservoir (Task 17 -...

40

CX-002612: Categorical Exclusion Determination | Department of...  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Exclusion Determination CX-002612: Categorical Exclusion Determination Modeling Carbon Dioxide Sequestration in Saline Aquifer and Depleted Oil Reservoir to Evaluate...

Note: This page contains sample records for the topic "determination modeling carbon" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


41

CX-008440: Categorical Exclusion Determination | Department of...  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Exclusion Determination CX-008440: Categorical Exclusion Determination Modeling Carbon Dioxide Sequestration in Saline Aquifer and Depleted Oil Reservoir (Task 17 -...

42

Mechanistic Modeling of an Underbalanced Drilling Operation Utilizing Supercritical Carbon Dioxide.  

E-Print Network (OSTI)

??Mechanistic modeling of an underbalanced drilling operation using carbon dioxide has been developed in this research. The use of carbon dioxide in an underbalanced drilling… (more)

ALAdwani, Faisal Abdullah

2007-01-01T23:59:59.000Z

43

Integrated Analysis and Application of Reservoir Models to Early Permian Detrital Carbonate Deposits, Midland Basin, Texas  

E-Print Network (OSTI)

A 3-D seismic volume, wireline logs and core data were integrated to determine the spatial distribution of porous reservoirs within the Wolfcampian-Leonardian detrital carbonate slope and basin strata in Glasscock County, Texas. A 3-D seismic amplitude volume was used to construct a seismic facies analysis of the detrital carbonate section, and generated attribute volumes helped identify detrital carbonate depositional trends, as well as establish a potential correlation between thick detrital carbonate intervals and associated amplitude response. Eight lithofacies were identified in core and were subsequently classified into three main facies: debris flow, grain flow/turbidite, and basinal shale. A facies type log was then created, which was used to supervise the creation of facies logs within other wells to ultimately use in the creation of a 3-D facies model. Cross sections through the study area show an increase in bathymetric relief beginning in Wolfcampian time and continuing through the Leonardian. Detrital carbonate deposition increases dramatically during the Leonardian, consisting of large gravity flows deposited basinward in a northwest-southeast linear trend, rapidly thinning basinward. Individual flows are discontinuous and bounded by basinal shale facies. Four seismic facies were identified within the interval of interest using a structurally smoothed attribute volume, while an RMS amplitude attribute volume provided a correlation between high RMS amplitude values and detrital carbonate thickness. A high RMS amplitude value corresponding to the debris flow facies was extracted from the RMS attribute volume in the form of a seismic geobody. Two facies models and one porosity model were generated by using upscaled values from the gamma ray, total porosity, and lithofacies logs, which were applied over areas with the densest well control. Although the facies model populated from upscaled GR values was useful in stratigraphic interpretation, it is determined that the models should be applied over areas with denser well spacing in order to provide a more accurate and geologically viable subsurface model.

Johnston, Travis 1987-

2012-12-01T23:59:59.000Z

44

Prospective Life-Cycle Modeling of Novel Carbon Capture Materials  

NLE Websites -- All DOE Office Websites (Extended Search)

Prospective Life-Cycle Modeling of Novel Carbon Capture Materials Prospective Life-Cycle Modeling of Novel Carbon Capture Materials Speaker(s): Roger Sathre Date: December 5, 2011 - 3:30pm Location: 90-4133 Seminar Host/Point of Contact: Anita Estner Barbara Adams In this presentation we describe the prospective life-cycle modeling of metal-organic frameworks (MOF), a novel type of material with the potential for efficiently capturing CO2. Life-cycle modeling of emerging technologies, conducted early in the innovation process, can generate knowledge that can feed back to inform scientific discovery and development. We discuss the challenges of credibly modeling a system that does not yet exist, and describe methodological approaches including parametric system modeling (quantifying relations between system elements), scenario projections (defining plausible pathways for system scale-up),

45

Development of a linear predictive model for carbon dioxide sequestration in deep saline carbonate aquifers  

Science Conference Proceedings (OSTI)

CO"2 injection into deep saline aquifers is a preferred method for mitigating CO"2 emission. Although deep saline aquifers are found in many sedimentary basins and provide very large storage capacities, several numerical simulations are needed before ... Keywords: CO2 sequestration, Deep saline carbonate aquifer, Latin hypercube space filling design, Predictive model

Sultan Anbar; Serhat Akin

2011-11-01T23:59:59.000Z

46

Computer Modeling of Carbon Metabolism Enables Biofuel Engineering (Fact Sheet)  

DOE Green Energy (OSTI)

In an effort to reduce the cost of biofuels, the National Renewable Energy Laboratory (NREL) has merged biochemistry with modern computing and mathematics. The result is a model of carbon metabolism that will help researchers understand and engineer the process of photosynthesis for optimal biofuel production.

Not Available

2011-09-01T23:59:59.000Z

47

The Carbon Cycle as the Main Determinant of Glacial-Interglacial Periods  

E-Print Network (OSTI)

An intriguing problem in climate science is the existence of Earth's glacial cycle. We show that it is possible to generate these periodic changes in climate by means of the Earth's carbon cycle as the main source factor. The carbon exchange between the Ocean, the Continent and the Atmosphere is modeled by means of a Lotka-Volterra three species system and the resulting atmospheric carbon cycle is used as the unique radiative forcing mechanism. It is shown that the carbon dioxide and temperature paths that are thus obtained have the same qualitative structure as the 100 kyr glacial-interglacial cycles depicted by the Vostok ice core data, reproducing the asymmetries of rapid heating--slow cooling, and short interglacial--long glacial ages.

de la Cuesta, Diego Jiménez; Núñez, Darío; Rumbos, Beatriz; Vergara-Cervantes, Carlos

2013-01-01T23:59:59.000Z

48

ON CALCULATING THE TRANSFER OF CARBON-13 IN RESERVOIR MODELS OF THE CARBON CYCLE  

E-Print Network (OSTI)

7. Keeling. C. D. 1973. The carbon dioxide cycle: reservoirexchange of atmospheric carbon dioxide with the oceans andmodel to study the carbon dioxide exchange in nature. Tellus

Tans, Pieter P.

2013-01-01T23:59:59.000Z

49

Transport Models for Radioactive Carbon Dioxide at RWMC  

SciTech Connect

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

Hull, Laurence Charles; Hohorst, Frederick August

2001-12-01T23:59:59.000Z

50

Determination of free CO2 in emergent groundwaters using a commercial beverage carbonation meter  

Science Conference Proceedings (OSTI)

Dissolved CO{sub 2} in groundwater is frequently supersaturated relative to its equilibrium with atmospheric partial pressure and will degas when it is conveyed to the surface. Estimates of dissolved CO{sub 2} concentrations can vary widely between different hydrochemical facies because they have different sources of error (e.g., rapid degassing, low alkalinity, non-carbonate alkalinity). We sampled 60 natural spring and mine waters using a beverage industry carbonation meter, which measures dissolved CO{sub 2} based on temperature and pressure changes as the sample volume is expanded. Using a modified field protocol, the meter was found to be highly accurate in the range 0.2–35 mMCO{sub 2}. The meter provided rapid, accurate and precise measurements of dissolved CO{sub 2} in natural waters for a range of hydrochemical facies. Dissolved CO{sub 2} concentrations measured in the field with the carbonation meter were similar to CO{sub 2} determined using the pH-alkalinity approach, but provided immediate results and avoided errors from alkalinity and pH determination. The portability and ease of use of the carbonation meter in the field made it well-suited to sampling in difficult terrain. The carbonation meter has proven useful in the study of aquatic systems where CO{sub 2} degassing drives geochemical changes that result in surficial mineral precipitation and deposition, such as tufa, travertine and mine drainage deposits.

Vesper, Dorothy J.; Edenborn, Harry M.

2012-03-12T23:59:59.000Z

51

An Integrated Modeling Framework for Carbon Capture and Storage Technologies  

NLE Websites -- All DOE Office Websites (Extended Search)

Karen L. cohen Karen L. cohen Project Manager National Energy Technology Laboratory 626 Cochrans Mill Road P.O. Box 10940 Pittsburgh, PA 15236 412-386-6667 karen.cohen@netl.doe.gov Edward s. Rubin Carnegie Mellon University 5000 Forbes Avenue 128A Baker Hall Pittsburgh, PA 15213 412-268-5897 rubin@cmu.edu An IntegrAted ModelIng FrAMework For CArbon CApture And StorAge teChnologIeS Background The U.S. Department of Energy's (DOE) National Energy Technology Laboratory (NETL) is developing safe, lower-cost methods of carbon dioxide (CO 2 ) capture and storage (CCS) as a potential option for climate change mitigation. In addition to technology development, there is a need for modeling and assessment tools to evaluate and compare the cost and effectiveness of CCS methods. Analytical

52

Wellbore flow model for carbon dioxide and brine  

E-Print Network (OSTI)

to two geologic carbon sequestration sites, Energy Procedia,from geologic carbon sequestration (GCS) sites, especiallyKeywords: geologic carbon sequestration; well leakage,

Pan, L.

2009-01-01T23:59:59.000Z

53

Climate–Carbon Cycle Feedback Analysis: Results from the C4MIP Model Intercomparison  

Science Conference Proceedings (OSTI)

Eleven coupled climate–carbon cycle models used a common protocol to study the coupling between climate change and the carbon cycle. The models were forced by historical emissions and the Intergovernmental Panel on Climate Change (IPCC) Special ...

P. Friedlingstein; P. Cox; R. Betts; L. Bopp; W. von Bloh; V. Brovkin; P. Cadule; S. Doney; M. Eby; I. Fung; G. Bala; J. John; C. Jones; F. Joos; T. Kato; M. Kawamiya; W. Knorr; K. Lindsay; H. D. Matthews; T. Raddatz; P. Rayner; C. Reick; E. Roeckner; K.-G. Schnitzler; R. Schnur; K. Strassmann; A. J. Weaver; C. Yoshikawa; N. Zeng

2006-07-01T23:59:59.000Z

54

Gas permeation carbon capture --- Process modeling and optimization  

SciTech Connect

A multi-staged gas permeation carbon capture process model was developed in Aspen Custom Modeler{reg_sign} (ACM) and optimized in the context of the retrofit of a 550 MW subcritical pulverized coal (PC) power plant. The gas permeation stages in the process are described by a custom multi-component, hollowfiber membrane model. Gas transport across the asymmetric membrane was modeled according to the solution-diffusion model for the selective skin layer and the assumption of negligible flux resistance by the porous support. Counter-current, one-dimensional plug flow was assumed with permeate pressure drop in the fiber lumen side due to capillary constrained flow. A modular optimization framework was used to minimize the levelized cost of electricity (LCOE) by optimizing a set of key process variables. The framework allows the external control of multiple simulation modules from different software packages from a common interface.

Morinelly, Juan; Miller, David

2011-01-01T23:59:59.000Z

55

Validation and Comparison of Carbon Sequestration Project Cost Models with Project Cost Data Obtained from the Southwest Partnership  

SciTech Connect

Obtaining formal quotes and engineering conceptual designs for carbon dioxide (CO{sub 2}) sequestration sites and facilities is costly and time-consuming. Frequently, when looking at potential locations, managers, engineers and scientists are confronted with multiple options, but do not have the expertise or the information required to quickly obtain a general estimate of what the costs will be without employing an engineering firm. Several models for carbon compression, transport and/or injection have been published that are designed to aid in determining the cost of sequestration projects. A number of these models are used in this study, including models by J. Ogden, MIT's Carbon Capture and Sequestration Technologies Program Model, the Environmental Protection Agency and others. This report uses the information and data available from several projects either completed, in progress, or conceptualized by the Southwest Regional Carbon Sequestration Partnership on Carbon Sequestration (SWP) to determine the best approach to estimate a project's cost. The data presented highlights calculated versus actual costs. This data is compared to the results obtained by applying several models for each of the individual projects with actual cost. It also offers methods to systematically apply the models to future projects of a similar scale. Last, the cost risks associated with a project of this scope are discussed, along with ways that have been and could be used to mitigate these risks.

Robert Lee; Reid Grigg; Brian McPherson

2011-04-15T23:59:59.000Z

56

Soil carbon model Yasso07 graphical user interface  

E-Print Network (OSTI)

In this article, we present a graphical user interface software for the litter decomposition and soil carbon model Yasso07 and an overview of the principles and formulae it is based on. The software can be used to test the model and use it in simple applications. Yasso07 is applicable to upland soils of different ecosystems worldwide, because it has been developed using data covering the global climate conditions and representing various ecosystem types. As input information, Yasso07 requires data on litter input to soil, climate conditions, and land-use change if any. The model predictions are given as probability densities representing the uncertainties in the parameter values of the model and those in the input data - the user interface calculates these densities using a built-in Monte Carlo simulation.

Tuomi, Mikko; Repo, Anna; Vanhala, Pekka; Liski, Jari

2011-01-01T23:59:59.000Z

57

Multicentury Changes to the Global Climate and Carbon Cycle: Results from a Coupled Climate and Carbon Cycle Model  

Science Conference Proceedings (OSTI)

A coupled climate and carbon (CO2) cycle model is used to investigate the global climate and carbon cycle changes out to the year 2300 that would occur if CO2 emissions from all the currently estimated fossil fuel resources were released to the ...

G. Bala; K. Caldeira; A. Mirin; M. Wickett; C. Delire

2005-11-01T23:59:59.000Z

58

Experimental and analytic studies to model kinetics and mass transport of carbon dioxide sequstration in depleted carbonate reservoirs  

SciTech Connect

There is undeniable evidence that concentration of carbon dioxide in the atmosphere is rising at an increasingly rapid rate primarily as the result of burning fossil fuels. Although the debate continues, most of the scientific community believes that higher levels of atmospheric CO2 will lead to a significant warming of the Earth’s climate and that there is already evidence that this is occurring. There are two ways to ameliorate this problem. One is to significantly reduce production of CO2, which is primarily a political-economic problem, and the other is to remove CO2 from emissions and/or the atmosphere and find some way to sequester it. Several possible ways to sequester CO2 are under investigation or have been suggested. These include removal by chemical reaction, deep seabed disposal, and pumping supercritical CO2 into various subsurface environments. Sequestration of carbon dioxide in depleted gas reservoirs appears to be a viable option, with a possible economic spin-off from the recovery of significant gas reserves. At the elevated temperatures and pressures encountered in reservoirs, carbon dioxide behaves as a supercritical fluid. Under these conditions, little was known regarding the, diffusion of carbon dioxide in natural gas, and displacement of natural gas by carbon dioxide. A major objective of this research was to obtain the necessary data to model these processes. Also, the added CO2 will react with reservoir waters that are often chemically complex high ionic strength brines making them more acidic. This can result in the dissolution of calcium carbonate (calcite) that is a common host rock or sandstone cement in reservoirs and lead to potentially serious problems for CO2 injection and the integrity of the reservoir. It was consequently a second major objective of this project to determine calcite solubility and dissolution kinetics in solutions representative of subsurface brines and produce a general dissolution rate equation. Both objectives were accomplished. Reservoir simulations indicated a large amount of CO2 would be sequestered, with the amount depending on reservoir water saturation. Simulation results also indicate a significant amount of natural gas could be produced. For an 80-acre pattern, natural gas production was calculated to be 3.2 BSCF or 63% of remaining gas-in-place for 30% reservoir water saturation. Gas revenues would help defray the cost of CO2 sequestration. Therefore, CO2 sequestration in depleted gas reservoirs appears to be a win-win technology. Considerable effort went into testing and refining the ability to predict calcite solubility in brines using a Pitzer-equation based computer model, with particular difficulties being encountered in solutions with high dissolved calcium concentrations. After that was accomplished, calcite dissolution kinetics were determined a wide range of brine compositions both including and not including potential inhibitors from 25 to 83 oC and a CO2 partial pressure from 0.1 to 1 atm. The reaction was found to be first order for undersaturations of 0.2 to ~1 and was surface controlled. The rate constant was fit to a multiple regression model, thus making it possible to predict calcite dissolution rates over a wide range of solution compositions, partial pressures of CO2 and temperature. Results indicate that equilibrium is likely to be reached relatively quickly in front of an advancing supercritical CO2 fluid.

Morse, John W; Mamora, Daulat

2006-10-31T23:59:59.000Z

59

Evaluation of Black Carbon Estimations in Global Aerosol Models  

DOE Green Energy (OSTI)

We evaluate black carbon (BC) model predictions from the AeroCom model intercomparison project by considering the diversity among year 2000 model simulations and comparing model predictions with available measurements. These model-measurement intercomparisons include BC surface and aircraft concentrations, aerosol absorption optical depth (AAOD) from AERONET and OMI retrievals and BC column estimations based on AERONET. In regions other than Asia, most models are biased high compared to surface concentration measurements. However compared with (column) AAOD or BC burden retreivals, the models are generally biased low. The average ratio of model to retrieved AAOD is less than 0.7 in South American and 0.6 in African biomass burning regions; both of these regions lack surface concentration measurements. In Asia the average model to observed ratio is 0.6 for AAOD and 0.5 for BC surface concentrations. Compared with aircraft measurements over the Americas at latitudes between 0 and 50N, the average model is a factor of 10 larger than observed, and most models exceed the measured BC standard deviation in the mid to upper troposphere. At higher latitudes the average model to aircraft BC is 0.6 and underestimate the observed BC loading in the lower and middle troposphere associated with springtime Arctic haze. Low model bias for AAOD but overestimation of surface and upper atmospheric BC concentrations at lower latitudes suggests that most models are underestimating BC absorption and should improve estimates for refractive index, particle size, and optical effects of BC coating. Retrieval uncertainties and/or differences with model diagnostic treatment may also contribute to the model-measurement disparity. Largest AeroCom model diversity occurred in northern Eurasia and the remote Arctic, regions influenced by anthropogenic sources. Changing emissions, aging, removal, or optical properties within a single model generated a smaller change in model predictions than the range represented by the full set of AeroCom models. Upper tropospheric concentrations of BC mass from the aircraft measurements are suggested to provide a unique new benchmark to test scavenging and vertical dispersion of BC in global models.

Koch, D.; Schulz, M.; Kinne, Stefan; McNaughton, C. S.; Spackman, J. R.; Balkanski, Y.; Bauer, S.; Berntsen, T.; Bond, Tami C.; Boucher, Olivier; Chin, M.; Clarke, A. D.; De Luca, N.; Dentener, F.; Diehl, T.; Dubovik, O.; Easter, Richard C.; Fahey, D. W.; Feichter, J.; Fillmore, D.; Freitag, S.; Ghan, Steven J.; Ginoux, P.; Gong, S.; Horowitz, L.; Iversen, T.; Kirkevag, A.; Klimont, Z.; Kondo, Yutaka; Krol, M.; Liu, Xiaohong; Miller, R.; Montanaro, V.; Moteki, N.; Myhre, G.; Penner, J.; Perlwitz, Ja; Pitari, G.; Reddy, S.; Sahu, L.; Sakamoto, H.; Schuster, G.; Schwarz, J. P.; Seland, O.; Stier, P.; Takegawa, Nobuyuki; Takemura, T.; Textor, C.; van Aardenne, John; Zhao, Y.

2009-11-27T23:59:59.000Z

60

Synthesis, characterization, and modeling of hydrogen storage in carbon aerogels  

DOE Green Energy (OSTI)

Carbon aerogels are a special class of open-cell foams with an ultrafine cell/pore size (<50 nm), high surface area (600-800 m{sup 2}/g), and a solid matrix composed of interconnected colloidal-like particles or fibers with characteristic diameters of 10 nm. These materials are usually synthesized from the sol-gel polymerization of resorcinol-formaldehyde or phenolic-furfural, followed by supercritical extraction of the solvent and pyrolysis in an inert atmosphere. The resultant aerogel has a nanocrystalline structure with micropores (<2 nm diameter) located within the solid matrix. Carbon aerogel monoliths can be prepared at densities ranging from 0.05-1.0 g/cm{sup 3}, leading to volumetric surface areas (> 500 m{sup 2}/cm{sup 3}) that are much larger than commercially available materials. This research program is directed at optimization of the aerogel structure for maximum hydrogen adsorption over a wide range of temperatures and pressures. Computer modeling of hydrogen adsorption at carbon surfaces was also examined.

Pekala, R.W.; Coronado, P.R.; Calef, D.F.

1995-04-01T23:59:59.000Z

Note: This page contains sample records for the topic "determination modeling carbon" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


61

Carbon Footprint and the Management of Supply Chains: Insights from Simple Models  

E-Print Network (OSTI)

Carbon Footprint and the Management of Supply Chains: Insights from Simple Models Saif Benjaafar1, we illustrate how carbon emission concerns could be integrated into operational decision-making with regard to procurement, production, and inventory management. We show how, by associating carbon emission

Benjaafar, Saifallah

62

AN INTEGRATED MODELING FRAMEWORK FOR CARBON MANAGEMENT TECHNOLOGIES  

Science Conference Proceedings (OSTI)

CO{sub 2} capture and storage (CCS) is gaining widespread interest as a potential method to control greenhouse gas emissions from fossil fuel sources, especially electric power plants. Commercial applications of CO{sub 2} separation and capture technologies are found in a number of industrial process operations worldwide. Many of these capture technologies also are applicable to fossil fuel power plants, although applications to large-scale power generation remain to be demonstrated. This report describes the development of a generalized modeling framework to assess alternative CO{sub 2} capture and storage options in the context of multi-pollutant control requirements for fossil fuel power plants. The focus of the report is on post-combustion CO{sub 2} capture using amine-based absorption systems at pulverized coal-fired plants, which are the most prevalent technology used for power generation today. The modeling framework builds on the previously developed Integrated Environmental Control Model (IECM). The expanded version with carbon sequestration is designated as IECM-cs. The expanded modeling capability also includes natural gas combined cycle (NGCC) power plants and integrated coal gasification combined cycle (IGCC) systems as well as pulverized coal (PC) plants. This report presents details of the performance and cost models developed for an amine-based CO{sub 2} capture system, representing the baseline of current commercial technology. The key uncertainties and variability in process design, performance and cost parameters which influence the overall cost of carbon mitigation also are characterized. The new performance and cost models for CO{sub 2} capture systems have been integrated into the IECM-cs, along with models to estimate CO{sub 2} transport and storage costs. The CO{sub 2} control system also interacts with other emission control technologies such as flue gas desulfurization (FGD) systems for SO{sub 2} control. The integrated model is applied to study the feasibility and cost of carbon capture and sequestration at both new and existing PC plants as well as new NGCC plants. The cost of CO{sub 2} avoidance using amine-based CO{sub 2} capture technology is found to be sensitive to assumptions about the reference plant design and operation, as well as assumptions about the CO{sub 2} capture system design. The case studies also reveal multi-pollutant interactions and potential tradeoffs in the capture of CO{sub 2}, SO{sub 2}, NO{sub 2} and NH{sub 3}. The potential for targeted R&D to reduce the cost of CO{sub 2} capture also is explored using the IECM-cs in conjunction with expert elicitations regarding potential improvements in key performance and cost parameters of amine-based systems. The results indicate that the performance of amine-based CO{sub 2} capture systems can be improved significantly, and the cost of CO{sub 2} capture reduced substantially over the next decade or two, via innovations such as new or improved sorbents with lower regeneration heat requirements, and improvements in power plant heat integration to reduce the (currently large) energy penalty of CO{sub 2} capture. Future work will explore in more detail a broader set of advanced technology options to lower the costs of CO{sub 2} capture and storage. Volume 2 of this report presents a detailed User's Manual for the IECM-cs computer model as a companion to the technical documentation in Volume 1.

Anand B. Rao; Edward S. Rubin; Michael B. Berkenpas

2004-03-01T23:59:59.000Z

63

Semi-analytical model for schottky-barrier carbon nanotube and graphene nanoribbon transistors  

Science Conference Proceedings (OSTI)

This paper describes a physics-based semi-analytical model for Schottky-barrier carbon nanotube (CNT) and graphene nanoribbon (GNR) transistors. The model includes the treatment of (i) both tunneling and thermionic currents, (ii) ambipolar conduction, ... Keywords: carbon nanotubes, graphene nanoribbons, models, schottky-barrier

Xuebei Yang; Gianluca Fiori; Giuseppe Iannaccone; Kartik Mohanram

2010-05-01T23:59:59.000Z

64

Carbon nanotubes and graphene in aqueous surfactant solutions : molecular simulations and theoretical modeling  

E-Print Network (OSTI)

This thesis describes combined molecular simulations and theoretical modeling studies, supported by experimental observations, on properties and applications of carbon nanotubes (CNTs) and graphene sheets dispersed in ...

Lin, Shangchao

2012-01-01T23:59:59.000Z

65

A Semi-Empirical Two Step Carbon Corrosion Reaction Model in PEM Fuel Cells  

SciTech Connect

The cathode CL of a polymer electrolyte membrane fuel cell (PEMFC) was exposed to high potentials, 1.0 to 1.4 V versus a reversible hydrogen electrode (RHE), that are typically encountered during start up/shut down operation. While both platinum dissolution and carbon corrosion occurred, the carbon corrosion effects were isolated and modeled. The presented model separates the carbon corrosion process into two reaction steps; (1) oxidation of the carbon surface to carbon-oxygen groups, and (2) further corrosion of the oxidized surface to carbon dioxide/monoxide. To oxidize and corrode the cathode catalyst carbon support, the CL was subjected to an accelerated stress test cycled the potential from 0.6 VRHE to an upper potential limit (UPL) ranging from 0.9 to 1.4 VRHE at varying dwell times. The reaction rate constants and specific capacitances of carbon and platinum were fitted by evaluating the double layer capacitance (Cdl) trends. Carbon surface oxidation increased the Cdl due to increased specific capacitance for carbon surfaces with carbon-oxygen groups, while the second corrosion reaction decreased the Cdl due to loss of the overall carbon surface area. The first oxidation step differed between carbon types, while both reaction rate constants were found to have a dependency on UPL, temperature, and gas relative humidity.

Young, Alan; Colbow, Vesna; Harvey, David; Rogers, Erin; Wessel, Silvia

2013-01-01T23:59:59.000Z

66

The National Energy Modeling System: An Overview 1998 - Carbon Emissions  

Gasoline and Diesel Fuel Update (EIA)

CARBON EMISSIONS CARBON EMISSIONS A part of the integrating module, the carbon emissions submodule (CEM) computes the carbon emissions due to the combustion of energy. The coefficients for carbon emissions are derived from Energy Information Administration, Emissions of Greenhouse Gases in the United States 1996, published in October 1997. The calculations account for the fact that some fossil fuels are used for nonfuel purposes, such as feedstocks, and thus the carbon in the fuel is sequestered in the end product. CEM also allows for several carbon policy evaluation options to be imposed within NEMS. Although none of the policy options are assumed in the Annual Energy Outlook 1998, the options can be used in special analyses to simulate potential market-based approaches to meet national carbon emission

67

A Hydro-mechanical Model and Analytical Solutions for Geomechanical Modeling of Carbon Dioxide Geological Sequestration  

SciTech Connect

We present a hydro-mechanical model for geological sequestration of carbon dioxide. The model considers the poroelastic effects by taking into account the coupling between the geomechanical response and the fluid flow in greater detail. The simplified hydro-mechanical model includes the geomechanical part that relies on the linear elasticity, while the fluid flow is based on the Darcy’s law. Two parts were coupled using the standard linear poroelasticity. Analytical solutions for pressure field were obtained for a typical geological sequestration scenario. The model predicts the temporal and spatial variation of pressure field and effects of permeability and elastic modulus of formation on the fluid pressure distribution.

Xu, Zhijie; Fang, Yilin; Scheibe, Timothy D.; Bonneville, Alain HR

2012-05-15T23:59:59.000Z

68

Characterization and Modeling of Carbon Nanotube-Based Damage ...  

Science Conference Proceedings (OSTI)

Lignocellulosic-Based Carbon Fibers from Biofuel Production Wastes · Magnesium Sheets Produced by Extrusion · Magnetite Formation Observed with TEM on ...

69

CX-001426: Categorical Exclusion Determination | Department of...  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Exclusion Determination CX-001426: Categorical Exclusion Determination Development of Chemical Model to Predict the Interactions between Supercritical Carbon Dioxide and Reservoir...

70

A Mathematical Model of OxideCarbon Composite Electrode for Supercapacitors  

E-Print Network (OSTI)

A Mathematical Model of OxideÃ?Carbon Composite Electrode for Supercapacitors Hansung Kim for the general application of supercapacitors consisting of an oxide/carbon composite electrode. The model takes. Supercapacitors can be divided into two categories: electric double-layer capacitors and pseudocapacitors

Popov, Branko N.

71

Performance modelling and simulated availability of shell gasification and carbon recovery unit of urea plant  

Science Conference Proceedings (OSTI)

The present paper deals with the performance modelling and simulated availability of shell gasification and carbon recovery unit of urea plant. The fertilizer plant comprises of various units viz. shell gasification and carbon recovery, desulphurisation, ... Keywords: modelling, performance evaluation and maintenance strategies, steady state availability

Sunand Kumar; Sanjeev Kumar; P. C. Tewari

2007-08-01T23:59:59.000Z

72

Modeling of carbon nanotube field-effect transistor with nanowelding treatment  

Science Conference Proceedings (OSTI)

An efficient and universal numerical model of carbon nanotube (CN) field-effect transistor (FET) with nanowelding treatment has been developed. In this model, an analytic expression of carrier distribution of intrinsic CN is incorporated into the modified ... Keywords: 73.63.Fg, 85.35.Kt, Ambipolar conduction, Carbon nanotube field-effect transistor (CNFET), Newton-Raphson iteration, Schottky barrier (SB)

Wei Zhang; Changxin Chen; Yafei Zhang

2009-12-01T23:59:59.000Z

73

Economic model for height determination of high-rise buildings  

E-Print Network (OSTI)

At present, no clear concise method of optimal height determination for high-rise buildings is being practiced. The primary scope of this dissertation is to see if a practical model, decision making process and list of ...

Zafiris, Christopher

1984-01-01T23:59:59.000Z

74

Modeling Ambient Carbon Monoxide Trends to Evaluate Mobile Source Emissions Reductions  

Science Conference Proceedings (OSTI)

Regression models have been used with poor success to detect the effect of emission control programs in ambient concentration measurements of carbon monoxide. An advanced CO regression model is developed whose form is based on an understanding of ...

Robin L. Dennis; Mary W. Downton

1987-10-01T23:59:59.000Z

75

Terrestrial carbon cycle - climate relations in eight CMIP5 earth system models  

Science Conference Proceedings (OSTI)

Eight Earth System Models from the Coupled Model Intercomparison Project (CMIP5) are evaluated, focusing on both the net carbon dioxide flux and its components, and their relation with climatic variables (temperature, precipitation and soil ...

Pu Shao; Xubin Zeng; Koichi Sakaguchi; Russell K. Monson; Xiaodong Zeng

76

Evaluating the Carbon Cycle of a Coupled Atmosphere-Biosphere Model  

SciTech Connect

We investigate how well a coupled biosphere-atmosphere model, CCM3-IBIS, can simulate the functioning of the terrestrial biosphere and the carbon cycling through it. The simulated climate is compared to observations, while the vegetation cover and the carbon cycle are compared to an offline version of the biosphere model IBIS forced with observed climatic variables. The simulated climate presents some local biases that strongly affect the vegetation (e.g., a misrepresentation of the African monsoon). Compared to the offline model, the coupled model simulates well the globally averaged carbon fluxes and vegetation pools. The zonal mean carbon fluxes and the zonal mean seasonal cycle are also well represented except between 0{sup o} and 20{sup o}N due to the misrepresentation of the African monsoon. These results suggest that, despite regional biases in climate and ecosystem simulations, this coupled atmosphere-biosphere model can be used to explore geographic and temporal variations in the global carbon cycle.

Delire, C; Foley, J A; Thompson, S

2002-08-21T23:59:59.000Z

77

EasyDelta: A spreadsheet for kinetic modeling of the stable carbon isotope composition of natural gases  

Science Conference Proceedings (OSTI)

A new kinetic model and an Excel^(C) spreadsheet program for modeling the stable carbon isotope composition of natural gases is provided in this paper. The model and spreadsheet could be used to describe and predict the variances in stable carbon isotope ... Keywords: Carbon isotope, Excel spreadsheet, Kinetics, Modeling, Natural gas

Yan-Rong Zou; Lianyuan Wang; Yanhua Shuai; Ping'an Peng

2005-08-01T23:59:59.000Z

78

Evaluation of stress in bmi-carbon fiber laminate to determine the onset of microcracking  

E-Print Network (OSTI)

In this work the conditions for which a (0,90,90,0,0,90)s BMI-carbon fiber laminate will initiate transverse microcracking are determined for the fabrication of a cryogenic fuel tank for use in a Reusable Launch Vehicle (RLV). This is accomplished using a quadratic interaction criterion failure analysis on the total stress state at possible launch conditions. There are three major sources of stress, that is, thermal residual stress, internal pressure stress, and applied load stress, that are evaluated at the launch stage to determine the total stress state. To assess the accuracy of the analysis the well known X-33 cryogenic fuel tank failure was analyzed as an example. The results of the X-33 example show that the analysis accurately portrays the failure of the X-33 and provides evidence that the analysis can be used to provide reliable conditions for the initiation of microcracking. The final result of this study is a range of launch conditions that can be used without the initiation of microcracking and a limiting range of conditions that cause complete microcracking throughout the laminate.

Pickle, Brent Durrell

2004-12-01T23:59:59.000Z

79

COINS: an integrative modelling shell for carbon accounting and general ecological analysis  

Science Conference Proceedings (OSTI)

It is common for a range of models to be developed to investigate broadly similar ecological and environmental phenomena. This inevitably results in collections of models that, although individually possessing unique characteristics, also share a number ... Keywords: Carbon modelling, Model integration, Simulation modelling

S. H. Roxburgh; I. D. Davies

2006-03-01T23:59:59.000Z

80

Incorporating Carbon Capture and Storage Technologies in Integrated Assessment Models  

E-Print Network (OSTI)

carbon capture and storage, 2) a natural gas combined cycle technology with carbon capture and storage 1 power generation technologies are: 1) a natural gas combined cycle technology (advanced gas) without eight of technologies in the electric power sector: conventional fossil fuel, natural gas combined cycle

Note: This page contains sample records for the topic "determination modeling carbon" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


81

Nicaragua-Low-Carbon Energy for Central America: Building a Regional Model  

Open Energy Info (EERE)

Nicaragua-Low-Carbon Energy for Central America: Building a Regional Model Nicaragua-Low-Carbon Energy for Central America: Building a Regional Model Jump to: navigation, search Name Nicaragua-Low-Carbon Energy for Central America: Building a Regional Model Agency/Company /Organization World Watch Institute Sector Energy Focus Area Renewable Energy Topics Background analysis, Implementation, Low emission development planning, Policies/deployment programs Website http://www.worldwatch.org/node Country Nicaragua Central America References Low-Carbon Energy for Central America: Building a Regional Model[1] Overview "This project will design a unified low-carbon development strategy for Central America through the use of renewable energy and energy efficiency maps, followed by technical, economic, and social feasibility studies for

82

Low-Carbon Energy for Central America: Building a Regional Model | Open  

Open Energy Info (EERE)

Low-Carbon Energy for Central America: Building a Regional Model Low-Carbon Energy for Central America: Building a Regional Model Jump to: navigation, search Name Low-Carbon Energy for Central America: Building a Regional Model Agency/Company /Organization World Watch Institute Sector Energy Focus Area Renewable Energy Topics Background analysis, Implementation, Low emission development planning, Policies/deployment programs Website http://www.worldwatch.org/node Country Belize, Costa Rica, El Salvador, Guatemala, Honduras, Nicaragua, Panama Central America, Central America, Central America, Central America, Central America, Central America, Central America References Low-Carbon Energy for Central America: Building a Regional Model[1] Overview "This project will design a unified low-carbon development strategy for

83

Honduras-Low-Carbon Energy for Central America: Building a Regional Model |  

Open Energy Info (EERE)

Honduras-Low-Carbon Energy for Central America: Building a Regional Model Honduras-Low-Carbon Energy for Central America: Building a Regional Model Jump to: navigation, search Name Honduras-Low-Carbon Energy for Central America: Building a Regional Model Agency/Company /Organization World Watch Institute Sector Energy Focus Area Renewable Energy Topics Background analysis, Implementation, Low emission development planning, Policies/deployment programs Website http://www.worldwatch.org/node Country Honduras Central America References Low-Carbon Energy for Central America: Building a Regional Model[1] Overview "This project will design a unified low-carbon development strategy for Central America through the use of renewable energy and energy efficiency maps, followed by technical, economic, and social feasibility studies for

84

Belize-Low-Carbon Energy for Central America: Building a Regional Model |  

Open Energy Info (EERE)

Belize-Low-Carbon Energy for Central America: Building a Regional Model Belize-Low-Carbon Energy for Central America: Building a Regional Model Jump to: navigation, search Name Belize-Low-Carbon Energy for Central America: Building a Regional Model Agency/Company /Organization World Watch Institute Sector Energy Focus Area Renewable Energy Topics Background analysis, Implementation, Low emission development planning, Policies/deployment programs Website http://www.worldwatch.org/node Country Belize Central America References Low-Carbon Energy for Central America: Building a Regional Model[1] Overview "This project will design a unified low-carbon development strategy for Central America through the use of renewable energy and energy efficiency maps, followed by technical, economic, and social feasibility studies for

85

Costa Rica-Low-Carbon Energy for Central America: Building a Regional Model  

Open Energy Info (EERE)

Costa Rica-Low-Carbon Energy for Central America: Building a Regional Model Costa Rica-Low-Carbon Energy for Central America: Building a Regional Model Jump to: navigation, search Name Costa-Rica-Low-Carbon Energy for Central America: Building a Regional Model Agency/Company /Organization World Watch Institute Sector Energy Focus Area Renewable Energy Topics Background analysis, Implementation, Low emission development planning, Policies/deployment programs Website http://www.worldwatch.org/node Country Costa Rica Central America References Low-Carbon Energy for Central America: Building a Regional Model[1] Overview "This project will design a unified low-carbon development strategy for Central America through the use of renewable energy and energy efficiency maps, followed by technical, economic, and social feasibility studies for

86

Guatemala-Low-Carbon Energy for Central America: Building a Regional Model  

Open Energy Info (EERE)

Guatemala-Low-Carbon Energy for Central America: Building a Regional Model Guatemala-Low-Carbon Energy for Central America: Building a Regional Model Jump to: navigation, search Name Guatemala-Low-Carbon Energy for Central America: Building a Regional Model Agency/Company /Organization World Watch Institute Sector Energy Focus Area Renewable Energy Topics Background analysis, Implementation, Low emission development planning, Policies/deployment programs Website http://www.worldwatch.org/node Country Guatemala Central America References Low-Carbon Energy for Central America: Building a Regional Model[1] Overview "This project will design a unified low-carbon development strategy for Central America through the use of renewable energy and energy efficiency maps, followed by technical, economic, and social feasibility studies for

87

The Carbon Cycle Response to ENSO: A Coupled Climate–Carbon Cycle Model Study  

Science Conference Proceedings (OSTI)

There is significant interannual variability in the atmospheric concentration of carbon dioxide (CO2) even when the effect of anthropogenic sources has been accounted for. This variability is well correlated with the El Niño–Southern Oscillation (...

Chris D. Jones; Matthew Collins; Peter M. Cox; Steven A. Spall

2001-11-01T23:59:59.000Z

88

Modeling the heat and mass transfers in temperature-swing adsorption of volatile organic compounds onto activated carbons  

Science Conference Proceedings (OSTI)

A theoretical model was built to simulate the adsorption of volatile organic compounds (VOCs) onto activated carbons in a fixed bed. This model was validated on a set of experimental data obtained for the adsorption of acetone, ethyl formate, and dichloromethane onto five commercial activated carbons. The influence of operating conditions was modeled with various VOC contents at the inlet of the adsorber and superficial velocities of the gas-phase from 0.14 to 0.28 m.s{sup -1}. Breakthrough times and maximum temperature rises were computed with a coefficient of determination of 0.988 and 0.901, respectively. The simulation was then extended to the adsorption of mixtures of VOCs. From the comparison of simulation and experimental results, the advantage of accounting for dispersions of heat and mass is shown and the importance in taking into account the temperature effect on the equilibrium data is demonstrated. 29 refs., 6 figs., 1 tab.

Sylvain Giraudet; Pascaline Pre; Pierre Le Cloirec [Ecole des Mines de Nantes, Nantes (France)

2009-02-15T23:59:59.000Z

89

Application of Low-Cost Digital Elevation Models to Detect Change in Forest Carbon Sequestration Projects  

DOE Green Energy (OSTI)

This two-year study evaluated advanced multispectral digital imagery applications for assessment of forest carbon stock change. A series of bench and field studies in North Carolina and Ohio tested aerial assessments of forest change between two time periods using two software packages (ERDAS and TERREST) for Digital Elevation Model (DEM) creation, automated classification software (eCognition) for canopy segmentation and a multiple ranging laser designed to improve quality of elevation data. Results of the DEM software comparison showed that while TERREST has the potential to produce much higher resolution DEM than ERDAS, it is unable to resolve crucial canopy features adequately. Lab tests demonstrated that additional laser data improves image registration and Z-axis DEM quality. Data collected in the field revealed difficult challenges in correctly modeling the location of laser strike and subsequently determining elevations in both software packages. Automated software segmentation of tree canopies provided stem diameter and biomass carbon estimates that were within 3% of comparable ground based estimates in the Ohio site and produced similar biomass estimates for a limited number of plots in the Duke forest. Tree height change between time periods and canopy segmentation from multispectral imagery allowed calculation of forest carbon stock change at costs that are comparable to those for ground-based methods. This work demonstrates the potential of lower cost imagery systems enhanced with laser data to collect high quality imagery and paired laser data for forestry and environmental applications. Additional research on automated canopy segmentation and multi-temporal image registration is needed to refine these methods for commercial use.

Kenneth Glenn MacDicken

2007-07-31T23:59:59.000Z

90

Method of determining pH by the alkaline absorption of carbon dioxide  

DOE Patents (OSTI)

A method for measuring the concentration of hydroxides in alkaline solutions in a remote location using the tendency of hydroxides to absorb carbon dioxide. The method includes the passing of carbon dioxide over the surface of an alkaline solution in a remote tank before and after measurements of the carbon dioxide solution. A comparison of the measurements yields the absorption fraction from which the hydroxide concentration can be calculated using a correlation of hydroxide or pH to absorption fraction.

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

1992-01-01T23:59:59.000Z

91

DETERMINATION OF CARBON IN ATMOSPHERIC AEROSOLS BY DEUTERON-INDUCED NUCLEAR REACTIONS  

E-Print Network (OSTI)

deuteron irradiation of an atmospheric aerosol sample.CARBON IN ATMOSPHERIC AEROSOLS BY DEUTERON-INDUCED NUCLEARCARBON IN ATMOSPHERIC AEROSOLS BY DEUTERON-INDUCED NUCLEAR

Clemenson, Mark

2013-01-01T23:59:59.000Z

92

A Comprehensive Model for Evaluation of Carbon Footprint and Greenhouse Gages Emission in Household Biogas Plants  

Science Conference Proceedings (OSTI)

Based on Life Cycle Assessment and other related methods, this paper introduced a comprehensive model for the evaluation of the carbon footprint and greenhouse gases emission in household biogas plants including nearly all the processes of the household ... Keywords: Biogas Plant, Carbon Footprint, Life Cycle, Greenhouse Gas

Jie Zhou; Shubiao Wu; Wanqin Zhang; Changle Pang; Baozhi Wang; Renjie Dong; Li Chen

2012-07-01T23:59:59.000Z

93

Factors influencing anthropogenic carbon dioxide uptake in the North Atlantic in models of the ocean carbon cycle  

SciTech Connect

The uptake and storage of anthropogenic carbon in the North Atlantic is investigated using different configurations of ocean general circulation/carbon cycle models. We investigate how different representations of the ocean physics in the models, which represent the range of models currently in use, affect the evolution of CO{sub 2} uptake in the North Atlantic. The buffer effect of the ocean carbon system would be expected to reduce ocean CO{sub 2} uptake as the ocean absorbs increasing amounts of CO{sub 2}. We find that the strength of the buffer effect is very dependent on the model ocean state, as it affects both the magnitude and timing of the changes in uptake. The timescale over which uptake of CO{sub 2} in the North Atlantic drops to below preindustrial levels is particularly sensitive to the ocean state which sets the degree of buffering; it is less sensitive to the choice of atmospheric CO{sub 2} forcing scenario. Neglecting physical climate change effects, North Atlantic CO{sub 2} uptake drops below preindustrial levels between 50 and 300 years after stabilisation of atmospheric CO{sub 2} in different model configurations. Storage of anthropogenic carbon in the North Atlantic varies much less among the different model configurations, as differences in ocean transport of dissolved inorganic carbon and uptake of CO{sub 2} compensate each other. This supports the idea that measured inventories of anthropogenic carbon in the real ocean cannot be used to constrain the surface uptake. Including physical climate change effects reduces anthropogenic CO{sub 2} uptake and storage in the North Atlantic further, due to the combined effects of surface warming, increased freshwater input, and a slowdown of the meridional overturning circulation. The timescale over which North Atlantic CO{sub 2} uptake drops to below preindustrial levels is reduced by about one-third, leading to an estimate of this timescale for the real world of about 50 years after the stabilisation of atmospheric CO{sub 2}. In the climate change experiment, a shallowing of the mixed layer depths in the North Atlantic results in a significant reduction in primary production, reducing the potential role for biology in drawing down anthropogenic CO{sub 2}.

Smith, R.S.; Marotzke, J. [Max Planck Institute for Meteorology, Hamburg (Germany)

2008-09-30T23:59:59.000Z

94

Formation and emission of methane in rice soils: Experimental determination and modeling analysis. Final report  

DOE Green Energy (OSTI)

Rice paddy soils have been identified as a major source of methane emissions contributing to the observed atmospheric increase in methane. This points to the need for a method of quantifying and predicting methane emissions for the widely varying conditions used in rice agriculture throughout the world. In the present work, a mathematical model for estimating the emission of methane from rice paddy soils is developed and refined. Kinetic parameters for methanogenesis in a Louisiana rice soil are determined from laboratory data on methane production from acetic acid substrate. Use of a stirred reactor allows simultaneous measurement of acetate consumption and methane production while minimizing mass transfer limitations. An existing model for rice plant growth is utilized to provide data on the availability of root exudates as a carbon source for the methanogens. The final methane model includes the kinetic parameters, plant data, and estimated transport parameters. With adjustments in these parameters, it provides an acceptable match to field data.

Law, V.J.; Bhattacharya, S.K.

1993-08-31T23:59:59.000Z

95

Formation of Carbon Dwarfs  

E-Print Network (OSTI)

We consider the formation of dwarf carbon stars via accretion from a carbon AGB companion in light of the new 107 object sample of Downes et al. (2004). This sample is now large enough to allow good mass determination via comparison of a composite spectrum to theoretical atmospheric models. Carbon dwarfs of spectral type M are indeed main sequence M dwarfs with enhanced metallicity and carbon abundance. We also calculate the predicted abundance of both M and of F/G carbon dwarfs, and show that the latter should be falsifiable in the near future.

Charles L. Steinhardt; Dimitar D. Sasselov

2005-02-08T23:59:59.000Z

96

EIA - The National Energy Modeling System: An Overview 2003-Carbon Dioxide  

Gasoline and Diesel Fuel Update (EIA)

Carbon Dioxide and Methane Emissions Carbon Dioxide and Methane Emissions The National Energy Modeling System: An Overview 2003 Carbon Dioxide and Methane Emissions The emissions policy submodule, part of the integrating module, estimates the energy–related emissions of carbon dioxide and methane. Carbon dioxide emissions are dependent on the fossil fuel consumed, the carbon content of the fuel, and the fraction of the fuel consumed in combustion. The product of the carbon dioxide coefficient and the combustion fraction yields a carbon dioxide emission factor. For fuel uses of fossil energy, the combustion fractions are assumed to be 0.99 for liquid fuels and 0.995 for gaseous fuels. The carbon dioxide potential of nonfuel uses of energy, such as asphalt and petrochemical feedstocks, is assumed to be sequestered in the product and not released to the atmosphere. The coefficients for carbon dioxide emissions are updated each year from the Energy Information Administration’s annual, Emissions of Greenhouse Gases in the United States.17

97

Determination of optimum electrolyte composition for molten carbonate fuel cells. Quarterly technical progress report, April--June 1987  

DOE Green Energy (OSTI)

The objective of this study is to determine the optimum electrolyte composition for molten carbonate fuel cells. To accomplish this, the contractor will provide: (1) Comprehensive reports of on-going efforts to optimize carbonate composition. (2) A list of characteristics affected by electrolyte composition variations (e.g. ionic conductivity, vapor pressure, melting range, gas solubility, exchange current densities on NiO, corrosion and cathode dissolution effects). (3) Assessment of the overall effects that these characteristics have on state-of-the-art cell voltage and lifetime.

Yuh, C.Y.; Pigeaud, A.

1987-12-31T23:59:59.000Z

98

Transient Response of a Global Ocean-Atmosphere Model to a Doubling of Atmospheric Carbon Dioxide  

Science Conference Proceedings (OSTI)

The transient response of climate to an instantaneous increase in the atmospheric concentration of carbon dioxide has been investigated by a general circulation model of the coupled ocean-atmosphere-land system with global geography and annual ...

Syukuro Manabe; Kirk Bryan; Michael J. Spelman

1990-05-01T23:59:59.000Z

99

Impact of an Updated Carbon Bond Mechanism on Predictions from the CMAQ Modeling System: Preliminary Assessment  

Science Conference Proceedings (OSTI)

An updated and expanded version of the Carbon Bond mechanism (CB05) has been incorporated into the Community Multiscale Air Quality (CMAQ) modeling system to more accurately simulate wintertime, pristine, and high-altitude situations. The CB05 ...

Golam Sarwar; Deborah Luecken; Greg Yarwood; Gary Z. Whitten; William P. L. Carter

2008-01-01T23:59:59.000Z

100

Climate–Carbon Cycle Model Response to Freshwater Discharge into the North Atlantic  

Science Conference Proceedings (OSTI)

The response of a coupled climate–carbon cycle model to discharge of freshwater into the North Atlantic is investigated with regard to cold reversals caused by meltwater from northern continental ice sheets such as the Younger Dryas during the ...

Atsushi Obata

2007-12-01T23:59:59.000Z

Note: This page contains sample records for the topic "determination modeling carbon" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


101

A modeling study on the climate impacts of black carbon aerosols  

E-Print Network (OSTI)

The role of black carbon (BC) aerosols in climate change is important because of its strong capability in causing extinction of solar radiation. A three-dimensional interactive aerosol-climate model has been used to study ...

Wang, Chien.

102

Terrestrial Carbon Sinks for the United States Predicted from MODIS Satellite Data and Ecosystem Modeling  

Science Conference Proceedings (OSTI)

A simulation model based on satellite observations of monthly vegetation cover from the Moderate Resolution Imaging Spectroradiometer (MODIS) was used to estimate monthly carbon fluxes in terrestrial ecosystems of the conterminous United States ...

Christopher Potter; Steven Klooster; Alfredo Huete; Vanessa Genovese

2007-08-01T23:59:59.000Z

103

GFDL’s ESM2 Global Coupled Climate–Carbon Earth System Models. Part II: Carbon System Formulation and Baseline Simulation Characteristics  

Science Conference Proceedings (OSTI)

The authors describe carbon system formulation and simulation characteristics of two new global coupled carbon–climate Earth System Models (ESM), ESM2M and ESM2G. These models demonstrate good climate fidelity as described in part I of this study ...

John P. Dunne; Jasmin G. John; Elena Shevliakova; Ronald J. Stouffer; John P. Krasting; Sergey L. Malyshev; P. C. D. Milly; Lori T. Sentman; Alistair J. Adcroft; William Cooke; Krista A. Dunne; Stephen M. Griffies; Robert W. Hallberg; Matthew J. Harrison; Hiram Levy; Andrew T. Wittenberg; Peter J. Phillips; Niki Zadeh

2013-04-01T23:59:59.000Z

104

Electrical utilities model for determining electrical distribution capacity  

Science Conference Proceedings (OSTI)

In its simplest form, this model was to obtain meaningful data on the current state of the Site`s electrical transmission and distribution assets, and turn this vast collection of data into useful information. The resulting product is an Electrical Utilities Model for Determining Electrical Distribution Capacity which provides: current state of the electrical transmission and distribution systems; critical Hanford Site needs based on outyear planning documents; decision factor model. This model will enable Electrical Utilities management to improve forecasting requirements for service levels, budget, schedule, scope, and staffing, and recommend the best path forward to satisfy customer demands at the minimum risk and least cost to the government. A dynamic document, the model will be updated annually to reflect changes in Hanford Site activities.

Fritz, R.L., Westinghouse Hanford, Richland, WA

1997-09-03T23:59:59.000Z

105

In situ determination of soil carbon pool by inelastic neutron scattering: Comparison with dry combustion  

SciTech Connect

There is a well-documented need for new in situ technologies for elemental analysis of soil, particularly for carbon (C), that overcome the limitations of the currently established chemical method by dry combustion (DC). In this work, we evaluated the concordance between the new INS (inelastic neutron scattering) technology and the DC method. The comparisons were carried out in the high C content (30-40%) organic soils of Willard, Ohio (4 sites), in natural forest in Willard, Ohio (1 site), and in a watershed pasture, with an {approx} 10{sup o} slope, in Coshocton, Ohio (5 sites). In addition to these stationary measurements, the organic soil and the pasture were continuously scanned with the inelastic neutron scattering (INS) system to obtain the transects mean C value. Both types of measurements, INS and DC, registered a decline in the surface density of C along transects in the watershed and in the organic soil. Similarly, both recorded a drop in C in the organic soil of about 0.16%. In the pastureland, declines in C levels of 0.08% and 0.10% were observed, respectively, by DC and INS. Combining the results from the three sites yielded a very satisfactory correlation between the INS- and DC-responses, with a regression coefficient, r{sup 2}, value of about 0.99. This suggests the possibility of establishing a universal regression line for various soil types. In addition, we demonstrated the ability of INS to measure the mean value over transect. In organic soil the mean value of an INS scan agreed, {approx} 0.5%, with the mean values of the DC analysis, whereas large discrepancy between these two was recorded in the pastureland. Overall, the various trends observed in C measurements by INS concurred with those determined by the DC method, so enhancing the confidence in the new INS technology.

Wielopolski, L.; Mitra, S.; Chatterjee, A.; Lal, R.

2011-01-01T23:59:59.000Z

106

Method of determining pH by the alkaline absorption of carbon dioxide  

DOE Patents (OSTI)

A method is described for measuring the concentration of hydroxides in alkaline solutions in a remote location using the tendency of hydroxides to absorb carbon dioxide. The method includes the passing of carbon dioxide over the surface of an alkaline solution in a remote tank before and after measurements of the carbon dioxide solution. A comparison of the measurements yields the absorption fraction from which the hydroxide concentration can be calculated using a correlation of hydroxide or pH to absorption fraction. 2 figs.

Hobbs, D.T.

1992-10-06T23:59:59.000Z

107

Short-Term Energy Outlook Model Documentation: Carbon Dioxide (CO2) Emissions Model  

Reports and Publications (EIA)

Description of the procedures for estimating carbon dioxide emissions in the Short-Term Energy Outlook

Information Center

2009-08-11T23:59:59.000Z

108

Review and model-based analysis of factors influencing soil carbon sequestration beneath switchgrass (Panicum virgatum)  

SciTech Connect

Abstract. A simple, multi-compartment model was developed to predict soil carbon sequestration beneath switchgrass (Panicum virgatum) plantations in the southeastern United States. Soil carbon sequestration is an important component of sustainable switchgrass production for bioenergy because soil organic matter promotes water retention, nutrient supply, and soil properties that minimize erosion. A literature review was included for the purpose of model parameterization and five model-based experiments were conducted to predict how changes in environment (temperature) or crop management (cultivar, fertilization, and harvest efficiency) might affect soil carbon storage and nitrogen losses. Predictions of soil carbon sequestration were most sensitive to changes in annual biomass production, the ratio of belowground to aboveground biomass production, and temperature. Predictions of ecosystem nitrogen loss were most sensitive to changes in annual biomass production, the soil C/N ratio, and nitrogen remobilization efficiency (i.e., nitrogen cycling within the plant). Model-based experiments indicated that 1) soil carbon sequestration can be highly site specific depending on initial soil carbon stocks, temperature, and the amount of annual nitrogen fertilization, 2) response curves describing switchgrass yield as a function of annual nitrogen fertilization were important to model predictions, 3) plant improvements leading to greater belowground partitioning of biomass could increase soil carbon sequestration, 4) improvements in harvest efficiency have no indicated effects on soil carbon and nitrogen, but improve cumulative biomass yield, and 5) plant improvements that reduce organic matter decomposition rates could also increase soil carbon sequestration, even though the latter may not be consistent with desired improvements in plant tissue chemistry to maximize yields of cellulosic ethanol.

Garten Jr, Charles T [ORNL

2012-01-01T23:59:59.000Z

109

Are the Effects of Black Carbon Overestimated in Climate Models? | U.S. DOE  

Office of Science (SC) Website

Are the Effects of Black Carbon Overestimated in Climate Models? Are the Effects of Black Carbon Overestimated in Climate Models? Biological and Environmental Research (BER) BER Home About Research Facilities Science Highlights Searchable Archive of BER Highlights External link Benefits of BER Funding Opportunities Biological & Environmental Research Advisory Committee (BERAC) News & Resources Contact Information Biological and Environmental Research U.S. Department of Energy SC-23/Germantown Building 1000 Independence Ave., SW Washington, DC 20585 P: (301) 903-3251 F: (301) 903-5051 E: sc.ber@science.doe.gov More Information » September 2012 Are the Effects of Black Carbon Overestimated in Climate Models? Atmospheric black carbon may not cause as much warming of the climate as we thought. Print Text Size: A A A Subscribe

110

Ocean Carbon Cycle Models from the Carbon Dioxide Information Analysis Center (CDIAC)  

DOE Data Explorer (OSTI)

•\tPacific data-model intercomparison from Patrick Wetzel (Max Planck Institute for Meteorology, Germany)

111

Modeling of C stars with core/mantle grains: Amorphous carbon + SiC  

E-Print Network (OSTI)

A set of 45 dust envelopes of carbon stars has been modeled. Among them, 34 were selected according to their dust envelope class (as suggested by Sloan, Little-Marenin & Price, 1998) and 11 are extreme carbon stars. The models were performed using a code that describes the radiative transfer in dust envelopes considering core/mantle grains composed by an alpha-SiC core and an amorphous carbon (A.C.) mantle. In addition, we have also computed models with a code that considers two kinds of grains - alpha-SiC and A.C. - simultaneously. Core-mantle grains seem to fit dust envelopes of evolved carbon stars, while two homogeneous grains are more able to reproduce thinner dust envelopes. Our results suggest that there exists an evolution of dust grains in the carbon star sequence. In the beginning of the sequence, grains are mainly composed of SiC and amorphous carbon; with dust envelope evolution, carbon grains are coated in SiC. This phenomena could perhaps explain the small quantity of SiC grains observed in the interstellar medium. However, in this work we consider only alpha-SiC grains, and the inclusion of beta-SiC grains can perhaps change some of there results.

S. Lorenz-Martins; F. X. de Araujo; S. J. Codina Landaberry; W. G. de Almeida; R. V. de Nader

2000-12-08T23:59:59.000Z

112

Time Scales of Terrestrial Carbon Response Related to Land-Use Application: Implications for Initializing an Earth System Model  

Science Conference Proceedings (OSTI)

The dynamic vegetation and carbon cycling component, LM3V, of the Geophysical Fluid Dynamics Laboratory (GFDL) prototype Earth system model (ESM2.1), has been designed to simulate the effects of land use on terrestrial carbon pools, including ...

Lori T. Sentman; Elena Shevliakova; Ronald J. Stouffer; Sergey Malyshev

2011-10-01T23:59:59.000Z

113

Conceptual design of an integrated technology model for carbon policy assessment.  

SciTech Connect

This report describes the conceptual design of a technology choice model for understanding strategies to reduce carbon intensity in the electricity sector. The report considers the major modeling issues affecting technology policy assessment and defines an implementable model construct. Further, the report delineates the basis causal structure of such a model and attempts to establish the technical/algorithmic viability of pursuing model development along with the associated analyses.

Backus, George A.; Dimotakes, Paul E. (NASA Jet Propulsion Laboratory, Pasadena, CA)

2011-01-01T23:59:59.000Z

114

Determination of the adsorptive capacity and adsorption isotherm of vapor-phase mercury chloride on powdered activated carbon using thermogravimetric analysis  

Science Conference Proceedings (OSTI)

This study investigated the use of thermogravimetric analysis (TGA) to determine the adsorptive capacity and adsorption isotherm of vapor-phase mercury chloride on powdered activated carbon (PAC). The technique is commonly applied to remove mercury-containing air pollutants from gas streams emitted from municipal solid waste incinerators. An alternative form of powdered activated carbon derived from a pyrolyzed tire char was prepared for use herein. The capacity of waste tire-derived PAC to adsorb vapor-phase HgCl{sub 2} was successfully measured using a self-designed TGA adsorption system. Experimental results showed that the maximum adsorptive capacities of HgCl{sub 2} were 1.75, 0.688, and 0.230 mg of HgCl{sub 2} per gram of powdered activated carbon derived from carbon black at 30, 70, and 150{sup o} for 500 {mu}g/m{sup 3} of HgCl{sub 2}, respectively. Four adsorption isotherms obtained using the Langmuir, Freundlich, Redlich-Peterson, and Brunauer-Emmett-eller (BET) models were used to simulate the adsorption of HgCl{sub 2}. The comparison of experimental data associated with the four adsorption isotherms indicated that BET fit the experimental results better than did the other isotherms at 30{sup o}, whereas the Freundlich isotherm fit the experimental results better at 70 and 150{sup o}. Furthermore, the calculations of the parameters associated with Langmuir and Freundlich isotherms revealed that the adsorption of HgCl{sub 2} by PAC-derived carbon black favored adsorption at various HgCl{sub 2} concentrations and temperatures. 35 refs., 7 figs., 3 tabs.

Hsun-Yu Lin; Chung-Shin Yuan; Wei-Ching Chen; Chung-Hsuang Hung [National Sun Yat-Sen University, Taiwan (China). Institute of Environmental Engineering

2006-11-15T23:59:59.000Z

115

A model-data intercomparison of CO2 exchange across North America: Results from the North American Carbon Program site synthesis  

Science Conference Proceedings (OSTI)

Our current understanding of terrestrial carbon processes is represented in various models used to integrate and scale measurements of CO2 exchange from remote sensing and other spatiotemporal data. Yet assessments are rarely conducted to determine how well models simulate carbon processes across vegetation types and environmental conditions. Using standardized data from the North American Carbon Program we compare observed and simulated monthly CO2 exchange from 44 eddy covariance flux towers in North America and 22 terrestrial biosphere models. The analysis period spans 220 site-years, 10 biomes, and includes two large-scale drought events, providing a natural experiment to evaluate model skill as a function of drought and seasonality. We evaluate models' ability to simulate the seasonal cycle of CO2 exchange using multiple model skill metrics and analyze links between model characteristics, site history, and model skill. Overall model performance was poor; the difference between observations and simulations was 10 times observational uncertainty, with forested ecosystems better predicted than nonforested. Model-data agreement was highest in summer and in temperate evergreen forests. In contrast, model performance declined in spring and fall, especially in ecosystems with large deciduous components, and in dry periods during the growing season. Models used across multiple biomes and sites, the mean model ensemble, and a model using assimilated parameter values showed high consistency with observations. Models with the highest skill across all biomes all used prescribed canopy phenology, calculated NEE as the difference between GPP and ecosystem respiration, and did not use a daily time step.

Schwalm, Christopher R. [Clark University; Williams, Christopher A. [Clark University; Schaefer, Kevin [University of Colorado, Boulder; Anderson, Ryan [University of Montana, Missoula; Arain, A. [McMaster University; Baker, Ian [Colorado State University, Fort Collins; Lokupitiya, Erandathie [Colorado State University, Fort Collins; Barr, Alan [Atmospheric Science and Technology Directorate, Saskatoo, SK, Canada; Black, T. A. [University of British Columbia, Vancouver; Gu, Lianhong [ORNL; Riciutto, Dan M. [Oak Ridge National Laboratory (ORNL)

2010-12-01T23:59:59.000Z

116

Rate of reduction of ore-carbon composites: Part II. Modeling of reduction in extended composites  

Science Conference Proceedings (OSTI)

A new process for ironmaking was proposed using a rotary hearth furnace and an iron bath smelter to produce iron employing wood charcoal as an energy source and reductant. This paper examines reactions in composite pellet samples with sizes close to sizes used in industrial practice (10 to 16 min in diameter). A model was constructed using the combined kinetic mechanism developed in Part I of this series of articles along with equations for the computation of pellet temperature and shrinkage during the reaction. The analysis of reaction rates measured for pellets with wood charcoal showed that heat transfer plays a significant role in their overall rate of reaction at elevated temperatures. The slower rates measured in pellets containing coal char show that the intrinsic kinetics of carbon oxidation is more significant than heat transfer. Model calculations suggest that the rates are highly sensitive to the thermal conductivity of pellets containing wood charcoal and are less sensitive to the external conditions of heat transfer. It was seen that the changes in pellet surface area and diameter due to shrinkage introduce little change on reaction rates. The model developed provides an adequate description of pellets of wood charcoal up to circa 90% of reduction. Experimentally determined rates of reduction of iron oxide by wood charcoal were approximately 5 to 10 times faster than rates measured in pellets with coal char.

Fortini, O.M.; Fruehan, R.J. [US Steel Research & Technological Center, Monroeville, PA (United States)

2005-12-01T23:59:59.000Z

117

Multi-Phase CFD Modeling of Solid Sorbent Carbon Capture System  

Science Conference Proceedings (OSTI)

Computational fluid dynamics (CFD) simulations are used to investigate a low temperature post-combustion carbon capture reactor. The CFD models are based on a small scale solid sorbent carbon capture reactor design from ADA-ES and Southern Company. The reactor is a fluidized bed design based on a silica-supported amine sorbent. CFD models using both Eulerian-Eulerian and Eulerian-Lagrangian multi-phase modeling methods are developed to investigate the hydrodynamics and adsorption of carbon dioxide in the reactor. Models developed in both FLUENT® and BARRACUDA are presented to explore the strengths and weaknesses of state of the art CFD codes for modeling multi-phase carbon capture reactors. The results of the simulations show that the FLUENT® Eulerian-Lagrangian simulations (DDPM) are unstable for the given reactor design; while the BARRACUDA Eulerian-Lagrangian model is able to simulate the system given appropriate simplifying assumptions. FLUENT® Eulerian-Eulerian simulations also provide a stable solution for the carbon capture reactor given the appropriate simplifying assumptions.

Ryan, Emily M.; DeCroix, David; Breault, Ronald W.; Xu, Wei; Huckaby, E. D.; Saha, Kringan; Darteville, Sebastien; Sun, Xin

2013-07-30T23:59:59.000Z

118

Determination of mixed hydrate thermodynamics for reservoir modeling.  

E-Print Network (OSTI)

??Natural gas hydrates are likely to contain more carbon than in all other fossil fuel reserves combined worldwide. Most of the natural gas hydrate deposits… (more)

Garapati, Nagasree.

2009-01-01T23:59:59.000Z

119

Techno-Economic Models for Carbon Dioxide Compression, Transport, and Storage & Correlations for Estimating Carbon Dioxide Density and Viscosity  

E-Print Network (OSTI)

Conference on Carbon Sequestration, Washington D.C. (May 14-Laboratory’s national carbon sequestration program, NatCarb,To be sure, carbon capture and sequestration is highly site

McCollum, David L; Ogden, Joan M

2006-01-01T23:59:59.000Z

120

Characterizing the performance of ecosystem models across time scales: A spectral analysis of the North American Carbon Program site-level synthesis  

Science Conference Proceedings (OSTI)

Ecosystem models are important tools for diagnosing the carbon cycle and projecting its behavior across space and time. Most assessments of model performance occur at individual temporal scales, but ecosystems respond to drivers at multiple time scales. Spectral methods, such as wavelet analyses, present an alternative approach that enables the identification of the dominant time scales contributing to model performance in the frequency domain. In this study we used wavelet analyses to synthesize the performance of twenty-one ecosystem models at nine eddy-covariance towers as part of the North American Carbon Program's site-level inter-comparison. This study expands upon previous single-site and single-model analyses to determine what patterns of model failure are consistent across a diverse range of models and sites.

Dietze, Michael; Vargas, Rodrigo; Richardson, Andrew D.; Stoy, Paul C.; Barr, Alan; Anderson, Ryan; Arain, M. A.; Baker, Ian; Black, T. Andrew; Chen, Jing Ming; Ciais, Philippe; Flanagan, Lawrence; Gough, Christopher; Grant, R. F.; Hollinger, D.; Izaurralde, Roberto C.; Kucharik, Chris; Lafleur, Peter; Liu, Shuguang; Lokupitiya, Erandathie; Luo, Yiqi; Munger, J. W.; Peng, Changhui; Poulter, Benjamin; Price, David T.; Ricciuto, Daniel M.; Riley, William; Sahoo, Alok Kumar; Schaefer, Kevin; Suyker, Andrew E.; Tian, Hanqin; Tonitto, Christine; Verbeeck, Hans; Verma, Shashi B.; Wang, Weifeng; Weng, Ensheng

2011-12-20T23:59:59.000Z

Note: This page contains sample records for the topic "determination modeling carbon" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


121

Assessment of Existing Carbon Dioxide Equation of State Models and Experimental Databases  

Science Conference Proceedings (OSTI)

This report provides information that increases the knowledge base and strengthens the understanding of existing equation of state EOS models, as well as how closely the results of these models compare to available experimental databases for CO2 mixtures. The primary interest is in CO2 mixtures that result from coal combustion processes and carbon capture and storage CCS applications for electric power generation.

2010-12-23T23:59:59.000Z

122

Measurement of carbon capture efficiency and stored carbon leakage  

DOE Patents (OSTI)

Data representative of a measured carbon dioxide (CO.sub.2) concentration and of a measured oxygen (O.sub.2) concentration at a measurement location can be used to determine whether the measured carbon dioxide concentration at the measurement location is elevated relative to a baseline carbon dioxide concentration due to escape of carbon dioxide from a source associated with a carbon capture and storage process. Optionally, the data can be used to quantify a carbon dioxide concentration increase at the first location that is attributable to escape of carbon dioxide from the source and to calculate a rate of escape of carbon dioxide from the source by executing a model of gas-phase transport using at least the first carbon dioxide concentration increase. Related systems, methods, and articles of manufacture are also described.

Keeling, Ralph F.; Dubey, Manvendra K.

2013-01-29T23:59:59.000Z

123

Pore accessibility by methane and carbon dioxide in coal as determined by neutron scattering  

SciTech Connect

Contrast-matching ultrasmall-angle neutron scattering (USANS) and small-angle neutron scattering (SANS) techniques were used for the first time to determine both the total pore volume and the fraction of the pore volume that is inaccessible to deuterated methane, CD{sub 4}, in four bituminous coals in the range of pore sizes between {approx}10 {angstrom} and {approx}5 {micro}m. Two samples originated from the Illinois Basin in the U.S.A., and the other two samples were commercial Australian bituminous coals from the Bowen Basin. The total and inaccessible porosity were determined in each coal using both Porod invariant and the polydisperse spherical particle (PDSP) model analysis of the scattering data acquired from coals both in vacuum and at the pressure of CD{sub 4}, at which the scattering length density of the pore-saturating fluid is equal to that of the solid coal matrix (zero average contrast pressure). The total porosity of the coals studied ranged from 7 to 13%, and the volume of pores inaccessible to CD{sub 4} varied from {approx}13 to {approx}36% of the total pore volume. The volume fraction of inaccessible pores shows no correlation with the maceral composition; however, it increases with a decreasing total pore volume. In situ measurements of the structure of one coal saturated with CO{sub 2} and CD{sub 4} were conducted as a function of the pressure in the range of 1-400 bar. The neutron scattering intensity from small pores with radii less than 35 {angstrom} in this coal increased sharply immediately after the fluid injection for both gases, which demonstrates strong condensation and densification of the invading subcritical CO{sub 2} and supercritical methane in small pores.

He, Lilin [ORNL; Melnichenko, Yuri B [ORNL; Mastalerz, Maria [Indiana Geological Survey; Sakurovs, Richard [ORNL; Radlinski, Andrzej Pawell [ORNL; Blach, Tomasz P [ORNL

2012-01-01T23:59:59.000Z

124

CX-008945: Categorical Exclusion Determination | Department of...  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

CX-008945: Categorical Exclusion Determination Simplified Predictive Models for Carbon Dioxide Sequestration Performance Assessment CX(s) Applied: A9 Date: 08152012...

125

CX-009347: Categorical Exclusion Determination | Department of...  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

CX-009347: Categorical Exclusion Determination Optimal Model Complexity in Geological Carbon Sequestration CX(s) Applied: A9 Date: 09212012 Location(s): Wyoming Offices(s):...

126

CX-008331: Categorical Exclusion Determination | Department of...  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Categorical Exclusion Determination Validation of Material Models for Automotive Carbon-Fiber Composite Structures CX(s) Applied: B3.6 Date: 04052012 Location(s):...

127

CX-008334: Categorical Exclusion Determination | Department of...  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Categorical Exclusion Determination Validation of Material Models for Automotive Carbon-Fiber Composite Structures CX(s) Applied: A9 Date: 04052012 Location(s): Michigan...

128

The Tension between Fire Risk and Carbon Storage: Evaluating U.S. Carbon and Fire Management Strategies through Ecosystem Models  

Science Conference Proceedings (OSTI)

Fire risk and carbon storage are related environmental issues because fire reduction results in carbon storage through the buildup of woody vegetation, and stored carbon is a fuel for fires. The sustainability of the U.S. carbon sink and the ...

C. M. Girod; G. C. Hurtt; S. Frolking; J. D. Aber; A. W. King

2007-01-01T23:59:59.000Z

129

New Computer Model Pinpoints Prime Materials for Carbon Capture  

NLE Websites -- All DOE Office Websites (Extended Search)

release and compression, and then developed a computer model to calculate this energy consumption for any material. Smit then obtained a database of 4 million zeolite...

130

Desert dust and anthropogenic aerosol interactions in the Community Climate System Model coupled-carbon-climate model  

Science Conference Proceedings (OSTI)

Coupled-carbon-climate simulations are an essential tool for predicting the impact of human activity onto the climate and biogeochemistry. Here we incorporate prognostic desert dust and anthropogenic aerosols into the CCSM3.1 coupled carbon-climate model and explore the resulting interactions with climate and biogeochemical dynamics through a series of transient anthropogenic simulations (20th and 21st centuries) and sensitivity studies. The inclusion of prognostic aerosols into this model has a small net global cooling effect on climate but does not significantly impact the globally averaged carbon cycle; we argue that this is likely to be because the CCSM3.1 model has a small climate feedback onto the carbon cycle. We propose a mechanism for including desert dust and anthropogenic aerosols into a simple carbon-climate feedback analysis to explain the results of our and previous studies. Inclusion of aerosols has statistically significant impacts on regional climate and biogeochemistry, in particular through the effects on the ocean nitrogen cycle and primary productivity of altered iron inputs from desert dust deposition.

Mahowald, Natalie [Cornell University; Rothenberg, D. [Cornell University; Lindsay, Keith [National Center for Atmospheric Research (NCAR); Doney, Scott C. [Woods Hole Oceanographic Institution; Moore, Jefferson Keith [University of California, Irvine; Randerson, James T. [University of California, Irvine; Thornton, Peter E [ORNL; Jones, C. D. [Hadley Center, Devon, England

2011-02-01T23:59:59.000Z

131

Assessing FPAR Source and Parameter Optimization Scheme in Application of a Diagnostic Carbon Flux Model  

Science Conference Proceedings (OSTI)

The combination of satellite remote sensing and carbon cycle models provides an opportunity for regional to global scale monitoring of terrestrial gross primary production, ecosystem respiration, and net ecosystem production. FPAR (the fraction of photosynthetically active radiation absorbed by the plant canopy) is a critical input to diagnostic models, however little is known about the relative effectiveness of FPAR products from different satellite sensors nor about the sensitivity of flux estimates to different parameterization approaches. In this study, we used multiyear observations of carbon flux at four eddy covariance flux tower sites within the conifer biome to evaluate these factors. FPAR products from the MODIS and SeaWiFS sensors, and the effects of single site vs. cross-site parameter optimization were tested with the CFLUX model. The SeaWiFs FPAR product showed greater dynamic range across sites and resulted in slightly reduced flux estimation errors relative to the MODIS product when using cross-site optimization. With site-specific parameter optimization, the flux model was effective in capturing seasonal and interannual variation in the carbon fluxes at these sites. The cross-site prediction errors were lower when using parameters from a cross-site optimization compared to parameter sets from optimization at single sites. These results support the practice of multisite optimization within a biome for parameterization of diagnostic carbon flux models.

Turner, D P; Ritts, W D; Wharton, S; Thomas, C; Monson, R; Black, T A

2009-02-26T23:59:59.000Z

132

DOE Hydrogen Analysis Repository: Carbon Dioxide Compression, Transport,  

NLE Websites -- All DOE Office Websites (Extended Search)

Carbon Dioxide Compression, Transport, and Storage Carbon Dioxide Compression, Transport, and Storage Project Summary Full Title: Techno-Economic Models for Carbon Dioxide Compression, Transport, and Storage & Correlations for Estimating Carbon Dioxide Density and Viscosity Project ID: 195 Principal Investigator: David McCollum Brief Description: This project addresses several components of carbon capture and storage (CCS) costs, provides technical models for determining the engineering and infrastructure requirements of CCS, and describes some correlations for estimating CO2 density and viscosity. Keywords: Pipeline, transportation, greenhouse gases (GHG), costs, technoeconomic analysis Purpose Estimate costs of carbon dioxide capture, compression, transport, storage, etc., and provide some technical models for determining the engineering and

133

Carbon monoxide oxidation over three different states of copper: Development of a model metal oxide catalyst  

SciTech Connect

Carbon monoxide oxidation was performed over the three different oxidation states of copper -- metallic (Cu), copper (I) oxide (Cu{sub 2}O), and copper (II) oxide (CuO) as a test case for developing a model metal oxide catalyst amenable to study by the methods of modern surface science and catalysis. Copper was deposited and oxidized on oxidized supports of aluminum, silicon, molybdenum, tantalum, stainless steel, and iron as well as on graphite. The catalytic activity was found to decrease with increasing oxidation state (Cu > Cu{sub 2}O > CuO) and the activation energy increased with increasing oxidation state (Cu, 9 kcal/mol < Cu{sub 2}O, 14 kcal/mol < CuO, 17 kcal/mol). Reaction mechanisms were determined for the different oxidation states. Lastly, NO reduction by CO was studied. A Cu and CuO catalyst were exposed to an equal mixture of CO and NO at 300--350 C to observe the production of N{sub 2} and CO{sub 2}. At the end of each reaction, the catalyst was found to be Cu{sub 2}O. There is a need to study the kinetics of this reaction over the different oxidation states of copper.

Jernigan, G.G. [California Univ., Berkeley, CA (United States). Dept. of Chemistry]|[Lawrence Berkeley Lab., CA (United States). Materials and Chemical Sciences Div.

1994-10-01T23:59:59.000Z

134

Bayesian Modelling Volatility of Growth Rate in Atmospheric Carbon Dioxide Concentrations  

Science Conference Proceedings (OSTI)

Atmospheric gases, such as carbon dioxide, ozone, methane, nitrous oxide, and etc., create a natural greenhouse effect and cause climate change. Therefore, modelling behavior of these gases could help policy makers to control greenhouse effects. In a ... Keywords: Stochastic volatility, Smooth transition autoregressive, Markov chain Monte Carlo, methods, Bayesian, ARCH, GARCH

Esmail Amiri

2009-12-01T23:59:59.000Z

135

NREL Carbon Metabolism Modeling Intends to Make Biofuels Engineering Routine and Reliable (Fact Sheet)  

DOE Green Energy (OSTI)

National Renewable Energy Laboratory (NREL) scientists, supported by the Department of Energy (DOE) Scientific Discovery through Advanced Computing (SciDAC) Program, have assembled and simulated a model of key eukaryotic carbon metabolism that intends to move biochemical simulations into new realms of chemical fidelity.

Not Available

2011-02-01T23:59:59.000Z

136

Impact of emissions, chemistry, and climate on atmospheric carbon monoxide : 100-year predictions from a global chemistry-climate model  

E-Print Network (OSTI)

The possible trends for atmospheric carbon monoxide in the next 100 yr have been illustrated using a coupled atmospheric chemistry and climate model driven by emissions predicted by a global economic development model. ...

Wang, Chien.; Prinn, Ronald G.

137

Model Estimates of the Land and Ocean Contributions to Biospheric Carbon and Water Fluxes Using MODIS Satellite Data  

Science Conference Proceedings (OSTI)

Land and ocean are often treated separately in modeling studies despite their close links through the carbon, water, and energy cycles. However, biospheric models, particularly when used in conjunction with recent satellite datasets, provide a new,...

Paul B. Alton; Per E. Bodin

2011-07-01T23:59:59.000Z

138

Modeling and Scaling Coupled Energy, Water, and Carbon Fluxes Based on Remote Sensing: An Application to Canada’s Landmass  

Science Conference Proceedings (OSTI)

Land surface models (LSMs) need to be coupled with atmospheric general circulation models (GCMs) to adequately simulate the exchanges of energy, water, and carbon between the atmosphere and terrestrial surfaces. The heterogeneity of the land ...

Baozhang Chen; Jing M. Chen; Gang Mo; Chiu-Wai Yuen; Hank Margolis; Kaz Higuchi; Douglas Chan

2007-04-01T23:59:59.000Z

139

MODELING AND DESIGN FOR A DIRECT CARBON FUEL CELL WITH ENTRAINED FUEL AND OXIDIZER  

DOE Green Energy (OSTI)

The novel molten carbonate fuel cell design described in this report uses porous bed electrodes. Molten carbonate, with carbon fuel particles and oxidizer entrained, is circulated through the electrodes. Carbon may be reacted directly, without gasification, in a molten carbonate fuel cell. The cathode reaction is 2CO{sub 2} + O{sub 2} 4e{sup -} {yields} 2CO{sub 3}{sup =}, while the anode reaction can be either C + 2CO{sub 3}{sup =} {yields} 3CO{sub 2} + 4e{sup -} or 2C + CO{sub 3}{sup =} {yields} 3CO + 2e{sup -}. The direct carbon fuel cell has an advantage over fuel cells using coal-derived synthesis gas in that it provides better overall efficiency and reduces equipment requirements. Also, the liquid electrolyte provides a means for transporting the solid carbon. The porous bed cell makes use of this carbon transport ability of the molten salt electrolyte. A one-dimensional model has been developed for predicting the performance of this cell. For the cathode, dependent variables are superficial O{sub 2} and CO{sub 2} fluxes in the gas phase, superficial O{sub 2} and CO{sub 2} fluxes in the liquid phase, superficial current density through the electrolyte, and electrolyte potential. The variables are related by correlations, from the literature, for gas-liquid mass transfer, liquid-solid mass transfer, cathode current density, electrode overpotential, and resistivity of a liquid with entrained gas. For the anode, dependent variables are superficial CO{sub 2} flux in the gas phase, superficial CO{sub 2} flux in the liquid phase, superficial C flux, superficial current density through the electrolyte, and electrolyte potential. The same types of correlations relate the variables as in the cathode, with the addition of a correlation for resistivity of a fluidized bed. CO production is not considered, and axial dispersion is neglected. The model shows behavior typical of porous bed electrodes used in electrochemical processes. Efficiency is comparable to that of membrane electrode fuel cells. Effective bed depths are on the order of 1-5 centimeter, giving power/volume lower than for membrane electrode cells. The porous bed design, however, uses less expensive materials and is more resistant to fouling by coal impurities. The model will be used in the second phase of the project to design a laboratory-scale prototype cell. The prototype cell will demonstrate the concept and provide experimental data for improving the model.

Alan A. Kornhauser; Ritesh Agarwal

2005-04-01T23:59:59.000Z

140

Comparative performance of six carbon footprint models for use in Ireland  

SciTech Connect

Carbon footprint models are increasingly being used to manage personal and household carbon dioxide emissions. Six models were compared for their suitability for use in Ireland using typical data for a household of three people. The annual household energy and transportation emissions ranged from 10,540 to 17,361 kg CO{sub 2} yr{sup -1} (mean 12,886; sd 2135) rising to a total footprint of 12,053 to 27, 218 kg CO{sub 2} yr{sup -1} (mean 18,117; sd 5106) when aviation emissions were included. This represents a potential range for individual CO{sub 2} emissions of between 4018 and 9073 kg CO{sub 2}/person/annum, a variation of over 5 tonnes/person. The information provided by these models proved to be inconsistent and often contradictory. The high variability between models was due to a number of anomalies. When these were corrected mean household energy and transportation emissions fell to 12,130 kg CO{sub 2} yr{sup -1} (sd 805), with a total household footprint of 16,552 kg CO{sub 2} yr{sup -1} (sd 1101). Models vary in their complexity in terms of what is included in the overall estimation of emissions making a full analysis of the primary carbon footprint very difficult. When compared to current Irish conversion factors the corrected models either underestimated or overestimated CO{sub 2} emissions by approximately 10%. Current carbon footprint models excluded emissions from CH{sub 4} and N{sub 2}O underestimating CO{sub 2} emissions for the household by 1.8%.

Kenny, T. [Centre for the Environment, School of Natural Sciences, Trinity College, University of Dublin, Dublin 2 (Ireland); Gray, N.F. [Centre for the Environment, School of Natural Sciences, Trinity College, University of Dublin, Dublin 2 (Ireland)], E-mail: nfgray@tcd.ie

2009-01-15T23:59:59.000Z

Note: This page contains sample records for the topic "determination modeling carbon" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


141

Chombo-Crunch: Modeling Pore-Scale Reactive Transport in Carbon  

NLE Websites -- All DOE Office Websites (Extended Search)

Transient pH on calcite grains in capillary tube experiment. 1 billion grid points computed on 48K cores. 1 micron resolution. Transient pH on calcite grains in capillary tube experiment. 1 billion grid points computed on 48K cores. 1 micron resolution. Transient pH on calcite grains in capillary tube experiment. 1 billion grid points computed on 48K cores. 1 micron resolution. David Trebotich, Lawrence Berkeley National Laboratory Chombo-Crunch: Modeling Pore-Scale Reactive Transport in Carbon Sequestration PI Name: David Trebotich PI Email: treb@lbl.gov Institution: Lawrence Berkeley National Laboratory Allocation Program: INCITE Allocation Hours at ALCF: 80 Million Year: 2014 Research Domain: Earth Science Carbon sequestration, the process of capturing carbon dioxide (CO2) before it enters the atmosphere and transferring it into the earth, is a promising technique to help control greenhouse gas emissions. Researchers from the

142

Determination of Carbon Release Mechanisms in the DIII-D Divertors from Analysis of C I Line Profiles  

Science Conference Proceedings (OSTI)

During typical operation of the DIII-D tokamak, physical and chemical sputtering are the most important mechanisms for release of carbon at the divertor targets [Nuclear Fusion 42 614 (2002)]. Modeling of C I spectral line profiles is discussed as a technique for evaluating the relative contribution of each mechanism and is applied to several types of DIII-D discharges. The line shapes are symmetric and have shifts of about -0.03 if they are produced solely from molecular dissociation, but they exhibit distinct asymmetries and shifts approaching -0.20 if generated by physical sputtering. Modeled profiles must, in general, take account of both mechanisms in order to match experimental data. An alternate approach to distinguishing between the two processes, which relies on the relative intensities of C I, CD, and C2 emissions, is examined in light of conclusions drawn from the line-shape analysis.

Isler, Ralph C [ORNL; Brooks, N. H. [General Atomics, San Diego; West, W. P. [General Atomics, San Diego; McLean, A. G. [University of Toronto Institute for Aerospace Studies

2007-01-01T23:59:59.000Z

143

Geophysical monitoring and reactive transport modeling of ureolytically-driven calcium carbonate precipitation  

SciTech Connect

Ureolytically-driven calcium carbonate precipitation is the basis for a promising in-situ remediation method for sequestration of divalent radionuclide and trace metal ions. It has also been proposed for use in geotechnical engineering for soil strengthening applications. Monitoring the occurrence, spatial distribution, and temporal evolution of calcium carbonate precipitation in the subsurface is critical for evaluating the performance of this technology and for developing the predictive models needed for engineering application. In this study, we conducted laboratory column experiments using natural sediment and groundwater to evaluate the utility of geophysical (complex resistivity and seismic) sensing methods, dynamic synchrotron x-ray computed tomography (micro-CT), and reactive transport modeling for tracking ureolytically-driven calcium carbonate precipitation processes under site relevant conditions. Reactive transport modeling with TOUGHREACT successfully simulated the changes of the major chemical components during urea hydrolysis. Even at the relatively low level of urea hydrolysis observed in the experiments, the simulations predicted an enhanced calcium carbonate precipitation rate that was 3-4 times greater than the baseline level. Reactive transport modeling results, geophysical monitoring data and micro-CT imaging correlated well with reaction processes validated by geochemical data. In particular, increases in ionic strength of the pore fluid during urea hydrolysis predicted by geochemical modeling were successfully captured by electrical conductivity measurements and confirmed by geochemical data. The low level of urea hydrolysis and calcium carbonate precipitation suggested by the model and geochemical data was corroborated by minor changes in seismic P-wave velocity measurements and micro-CT imaging; the latter provided direct evidence of sparsely distributed calcium carbonate precipitation. Ion exchange processes promoted through NH{sub 4}{sup +} production during urea hydrolysis were incorporated in the model and captured critical changes in the major metal species. The electrical phase increases were potentially due to ion exchange processes that modified charge structure at mineral/water interfaces. Our study revealed the potential of geophysical monitoring for geochemical changes during urea hydrolysis and the advantages of combining multiple approaches to understand complex biogeochemical processes in the subsurface.

Wu, Y.; Ajo-Franklin, J.B.; Spycher, N.; Hubbard, S.S.; Zhang, G.; Williams, K.H.; Taylor, J.; Fujita, Y.; Smith, R.

2011-07-15T23:59:59.000Z

144

Geophysical Monitoring and Reactive Transport Modeling of Ureolytically-Driven Calcium Carbonate Precipitation  

Science Conference Proceedings (OSTI)

Ureolytically-driven calcium carbonate precipitation is the basis for a promising in-situ remediation method for sequestration of divalent radionuclide and trace metal ions. It has also been proposed for use in geotechnical engineering for soil strengthening applications. Monitoring the occurrence, spatial distribution, and temporal evolution of calcium carbonate precipitation in the subsurface is critical for evaluating the performance of this technology and for developing the predictive models needed for engineering application. In this study, we conducted laboratory column experiments using natural sediment and groundwater to evaluate the utility of geophysical (complex resistivity and seismic) sensing methods, dynamic synchrotron x-ray computed tomography (micro-CT), and reactive transport modeling for tracking ureolytically-driven calcium carbonate precipitation processes under site relevant conditions. Reactive transport modeling with TOUGHREACT successfully simulated the changes of the major chemical components during urea hydrolysis. Even at the relatively low level of urea hydrolysis observed in the experiments, the simulations predicted an enhanced calcium carbonate precipitation rate that was 3-4 times greater than the baseline level. Reactive transport modeling results, geophysical monitoring data and micro-CT imaging correlated well with reaction processes validated by geochemical data. In particular, increases in ionic strength of the pore fluid during urea hydrolysis predicted by geochemical modeling were successfully captured by electrical conductivity measurements and confirmed by geochemical data. The low level of urea hydrolysis and calcium carbonate precipitation suggested by the model and geochemical data was corroborated by minor changes in seismic P-wave velocity measurements and micro-CT imaging; the latter provided direct evidence of sparsely distributed calcium carbonate precipitation. Ion exchange processes promoted through NH4+ production during urea hydrolysis were incorporated in the model and captured critical changes in the major metal species. The electrical phase increases were potentially due to ion exchange processes that modified charge structure at mineral/water interfaces. Our study revealed the potential of geophysical monitoring for geochemical changes during urea hydrolysis and the advantages of combining multiple approaches to understand complex biogeochemical processes in the subsurface.

Yuxin Wu; Jonathan B. Ajo-Franklin; Nicolas Spycher; Susan S. Hubbard; Guoxiang Zhang; Kenneth H. Williams; Joanna Taylor; Yoshiko Fujita; Robert Smith

2011-09-01T23:59:59.000Z

145

Model Components of the Certification Framework for Geologic Carbon Sequestration Risk Assessment  

E-Print Network (OSTI)

to two geologic carbon sequestration sites, Energy Procedia,for Geologic Carbon Sequestration Based on Effectivefor geologic carbon sequestration risk assessment, Energy

Oldenburg, Curtis M.

2009-01-01T23:59:59.000Z

146

Thermodynamic Data for Geochemical Modeling of Carbonate Reactions Associated with CO2 Sequestration – Literature Review  

Science Conference Proceedings (OSTI)

Permanent storage of anthropogenic CO2 in deep geologic formations is being considered as a means to reduce the concentration of atmospheric CO2 and thus its contribution to global climate change. To ensure safe and effective geologic sequestration, numerous studies have been completed of the extent to which the CO2 migrates within geologic formations and what physical and geochemical changes occur in these formations when CO2 is injected. Sophisticated, computerized reservoir simulations are used as part of field site and laboratory CO2 sequestration studies. These simulations use coupled multiphase flow-reactive chemical transport models and/or standalone (i.e., no coupled fluid transport) geochemical models to calculate gas solubility, aqueous complexation, reduction/oxidation (redox), and/or mineral solubility reactions related to CO2 injection and sequestration. Thermodynamic data are critical inputs to modeling geochemical processes. The adequacy of thermodynamic data for carbonate compounds has been identified as an important data requirement for the successful application of these geochemical reaction models to CO2 sequestration. A review of thermodynamic data for CO2 gas and carbonate aqueous species and minerals present in published data compilations and databases used in geochemical reaction models was therefore completed. Published studies that describe mineralogical analyses from CO2 sequestration field and natural analogue sites and laboratory studies were also reviewed to identify specific carbonate minerals that are important to CO2 sequestration reactions and therefore require thermodynamic data. The results of the literature review indicated that an extensive thermodynamic database exists for CO2 and CH4 gases, carbonate aqueous species, and carbonate minerals. Values of ?fG298° and/or log Kr,298° are available for essentially all of these compounds. However, log Kr,T° or heat capacity values at temperatures above 298 K exist for less than approximately one-third of these compounds. Because the temperatures of host formations that will be used for CO2 injection and sequestration will be at tempera¬tures in the range of 50ºC to 100ºC or greater, the lack of high temperature thermodynamic values for key carbonate compounds especially minerals, will impact the accuracy of some modeling calculations.

Krupka, Kenneth M.; Cantrell, Kirk J.; McGrail, B. Peter

2010-09-28T23:59:59.000Z

147

A model-data intercomparison of CO2 exchange across North America: Results from the North American Carbon Program Site Synthesis  

Science Conference Proceedings (OSTI)

Our current understanding of terrestrial carbon processes is represented in various models used to integrate and scale measurements of CO{sub 2} exchange from remote sensing and other spatiotemporal data. Yet assessments are rarely conducted to determine how well models simulate carbon processes across vegetation types and environmental conditions. Using standardized data from the North American Carbon Program we compare observed and simulated monthly CO{sub 2} exchange from 44 eddy covariance flux towers in North America and 22 terrestrial biosphere models. The analysis period spans {approx}220 site-years, 10 biomes, and includes two large-scale drought events, providing a natural experiment to evaluate model skill as a function of drought and seasonality. We evaluate models' ability to simulate the seasonal cycle of CO{sub 2} exchange using multiple model skill metrics and analyze links between model characteristics, site history, and model skill. Overall model performance was poor; the difference between observations and simulations was {approx}10 times observational uncertainty, with forested ecosystems better predicted than nonforested. Model-data agreement was highest in summer and in temperate evergreen forests. In contrast, model performance declined in spring and fall, especially in ecosystems with large deciduous components, and in dry periods during the growing season. Models used across multiple biomes and sites, the mean model ensemble, and a model using assimilated parameter values showed high consistency with observations. Models with the highest skill across all biomes all used prescribed canopy phenology, calculated NEE as the difference between GPP and ecosystem respiration, and did not use a daily time step.

Schwalm, C.R.; Williams, C.A.; Schaefer, K.; Anderson, R.; Arain, M.A.; Baker, I.; Black, T.A.; Chen, G.; Ciais, P.; Davis, K. J.; Desai, A. R.; Dietze, M.; Dragoni, D.; Fischer, M.L.; Flanagan, L.B.; Grant, R.F.; Gu, L.; Hollinger, D.; Izaurralde, R.C.; Kucharik, C.; Lafleur, P.M.; Law, B.E.; Li, L.; Li, Z.; Liu, S.; Lokupitiya, E.; Luo, Y.; Ma, S.; Margolis, H.; Matamala, R.; McCaughey, H.; Monson, R. K.; Oechel, W. C.; Peng, C.; Poulter, B.; Price, D.T.; Riciutto, D.M.; Riley, W.J.; Sahoo, A.K.; Sprintsin, M.; Sun, J.; Tian, H.; Tonitto, C.; Verbeeck, H.; Verma, S.B.

2011-06-01T23:59:59.000Z

148

Description, calibration and sensitivity analysis of the local ecosystem submodel of a global model of carbon and nitrogen cycling and the water balance in the terrestrial biosphere  

Science Conference Proceedings (OSTI)

We have developed a geographically-distributed ecosystem model for the carbon, nitrogen, and water dynamics of the terrestrial biosphere TERRA. The local ecosystem model of TERRA consists of coupled, modified versions of TEM and DAYTRANS. The ecosystem model in each grid cell calculates water fluxes of evaporation, transpiration, and runoff; carbon fluxes of gross primary productivity, litterfall, and plant and soil respiration; and nitrogen fluxes of vegetation uptake, litterfall, mineralization, immobilization, and system loss. The state variables are soil water content; carbon in live vegetation; carbon in soil; nitrogen in live vegetation; organic nitrogen in soil and fitter; available inorganic nitrogen aggregating nitrites, nitrates, and ammonia; and a variable for allocation. Carbon and nitrogen dynamics are calibrated to specific sites in 17 vegetation types. Eight parameters are determined during calibration for each of the 17 vegetation types. At calibration, the annual average values of carbon in vegetation C, show site differences that derive from the vegetation-type specific parameters and intersite variation in climate and soils. From calibration, we recover the average C{sub v} of forests, woodlands, savannas, grasslands, shrublands, and tundra that were used to develop the model initially. The timing of the phases of the annual variation is driven by temperature and light in the high latitude and moist temperate zones. The dry temperate zones are driven by temperature, precipitation, and light. In the tropics, precipitation is the key variable in annual variation. The seasonal responses are even more clearly demonstrated in net primary production and show the same controlling factors.

Kercher, J.R. [Lawrence Livermore National Lab., CA (United States)] [Lawrence Livermore National Lab., CA (United States); Chambers, J.Q. [Lawrence Livermore National Lab., CA (United States)] [Lawrence Livermore National Lab., CA (United States); [California Univ., Santa Barbara, CA (United States). Dept. of Biological Sciences

1995-10-01T23:59:59.000Z

149

Pore-Level Modeling of Carbon Dioxide Sequestration in Brine Fields  

NLE Websites -- All DOE Office Websites (Extended Search)

Pore-Level Modeling of Carbon Dioxide Sequestration in Brine Fields Pore-Level Modeling of Carbon Dioxide Sequestration in Brine Fields M. Ferer, (mferer@wvu.edu) Department of Physics, West Virginia University, Morgantown, WV 26506-6315, Grant S. Bromhal, (bromhal@netl.doe.gov) US DOE, National Energy Technology Laboratory, Morgantown, WV 26507-0880; and Duane H. Smith, (dsmith@netl.doe.gov) US DOE, National Energy Technology Laboratory, Morgantown, WV 26507-0880 & Department of Physics, West Virginia University. Underground injection of gas is a common practice in the oil and gas industry. Injection into deep, brine-saturated formations is a commercially proven method of sequestering CO 2 . However, it has long been known that displacement of a connate fluid by a less viscous fluid produces unstable displacement fronts with significant fingering. This fingering allows only a

150

Topics in Bayesian sample size determination and Bayesian model selection.  

E-Print Network (OSTI)

??This dissertation contains three topics using the Bayesian paradigm for statistical inference. The first topic is related to Bayesian sample size determination with a misclassified… (more)

Cheng, Dunlei.

2007-01-01T23:59:59.000Z

151

Inverse Modeling for Determination of Thermal Properties of the ...  

Science Conference Proceedings (OSTI)

Thermal properties of ceramic shell depend on shell composition and fabrication ... Mathematical Modeling of a Compressible Oxygen Jet Interacting with a Free ... Multi-Physics Modeling of Molten Salt Transport in Solid Oxide Membrane ...

152

Discrete Fracture Network Models for Risk Assessment of Carbon Sequestration in Coal  

Science Conference Proceedings (OSTI)

A software package called DFNModeler has been developed to assess the potential risks associated with carbon sequestration in coal. Natural fractures provide the principal conduits for fluid flow in coal-bearing strata, and these fractures present the most tangible risks for the leakage of injected carbon dioxide. The objectives of this study were to develop discrete fracture network (DFN) modeling tools for risk assessment and to use these tools to assess risks in the Black Warrior Basin of Alabama, where coal-bearing strata have high potential for carbon sequestration and enhanced coalbed methane recovery. DFNModeler provides a user-friendly interface for the construction, visualization, and analysis of DFN models. DFNModeler employs an OpenGL graphics engine that enables real-time manipulation of DFN models. Analytical capabilities in DFNModeler include display of structural and hydrologic parameters, compartmentalization analysis, and fluid pathways analysis. DFN models can be exported to third-party software packages for flow modeling. DFN models were constructed to simulate fracturing in coal-bearing strata of the upper Pottsville Formation in the Black Warrior Basin. Outcrops and wireline cores were used to characterize fracture systems, which include joint systems, cleat systems, and fault-related shear fractures. DFN models were constructed to simulate jointing, cleating, faulting, and hydraulic fracturing. Analysis of DFN models indicates that strata-bound jointing compartmentalizes the Pottsville hydrologic system and helps protect shallow aquifers from injection operations at reservoir depth. Analysis of fault zones, however, suggests that faulting can facilitate cross-formational flow. For this reason, faults should be avoided when siting injection wells. DFN-based flow models constructed in TOUGH2 indicate that fracture aperture and connectivity are critical variables affecting the leakage of injected CO{sub 2} from coal. Highly transmissive joints near an injection well have potential to divert a large percentage of an injected CO{sub 2} stream away from a target coal seam. However, the strata-bound nature of Pottsville fracture systems is a natural factor that mitigates the risk of long-range leakage and surface seepage. Flow models indicate that cross-formational flow in strata-bound joint networks is low and is dissipated by about an order of magnitude at each successive bedding contact. These models help confirm that strata-bound joint networks are self-compartmentalizing and that the thick successions of interbedded shale and sandstone separating the Pottsville coal zones are confining units that protect shallow aquifers from injection operations at reservoir depth. DFN models are powerful tools for the simulation and analysis of fracture networks and can play an important role in the assessment of risks associated with carbon sequestration and enhanced coalbed methane recovery. Importantly, the stochastic nature DFN models dictates that they cannot be used to precisely reproduce reservoir conditions in a specific field area. Rather, these models are most useful for simulating the fundamental geometric and statistical properties of fracture networks. Because the specifics of fracture architecture in a given area can be uncertain, multiple realizations of DFN models and DFN-based flow models can help define variability that may be encountered during field operations. Using this type of approach, modelers can inform the risk assessment process by characterizing the types and variability of fracture architecture that may exist in geologic carbon sinks containing natural fractures.

Jack Pashin; Guohai Jin; Chunmiao Zheng; Song Chen; Marcella McIntyre

2008-07-01T23:59:59.000Z

153

Processing, Characterization and Modeling Carbon Nanotube Modified Interfaces in Hybrid Polymer Matrix Composites  

E-Print Network (OSTI)

Multifunctional hybrid composites are proposed as novel solutions to meet the demands in various industrial applications ranging from aerospace to biomedicine. The combination of carbon fibers and/or fabric, metal foil and carbon nanotubes are utilized to develop such composites. This study focuses on processing of and fracture toughness characterization of the carbon fiber reinforced polymer matrix composites (PMC) and the CNT modified interface between PMC and a metal foil. The laminate fabrication process using H-VARTM, and the mode I interlaminar fracture toughness via double cantilever beam (DCB) tests at both room temperature and high temperature are conducted. The cross-sections and fracture surfaces of the panels are characterized using optical and scanning electron microscopes to verify the existence of CNTs at the interface before and after fracture tests. The experimental results reveal that CNT’s improve bonding at the hybrid interfaces. Computational models are developed to assist the interpretation of experimental results and further investigate damage modes. In this work, analytical solutions to compute the total strain energy release rate as well as mode I and mode II strain energy release rates of asymmetric configurations layups are utilized. Finite element models are developed in which the virtual crack closure technique is adopted to calculate strain energy release rates and investigate the degree and effect of mode-mixity. Results from analytical solutions agree well with each other and with results obtained from finite element models.

Truong, Hieu 1990-

2012-12-01T23:59:59.000Z

154

Benchmarking GEANT4 nuclear models for carbon-therapy at 95 MeV/A  

E-Print Network (OSTI)

In carbon-therapy, the interaction of the incoming beam with human tissues may lead to the production of a large amount of nuclear fragments and secondary light particles. An accurate estimation of the biological dose deposited into the tumor and the surrounding healthy tissues thus requires sophisticated simulation tools based on nuclear reaction models. The validity of such models requires intensive comparisons with as many sets of experimental data as possible. Up to now, a rather limited set of double di erential carbon fragmentation cross sections have been measured in the energy range used in hadrontherapy (up to 400 MeV/A). However, new data have been recently obtained at intermediate energy (95 MeV/A). The aim of this work is to compare the reaction models embedded in the GEANT4 Monte Carlo toolkit with these new data. The strengths and weaknesses of each tested model, i.e. G4BinaryLightIonReaction, G4QMDReaction and INCL++, coupled to two di fferent de-excitation models, i.e. the generalized evaporation model and the Fermi break-up are discussed.

J. Dudouet; D. Cussol; D. Durand; M. Labalme

2013-09-06T23:59:59.000Z

155

Development and application of the EPIC model for carbon cycle, greenhouse-gas mitigation, and biofuel studies  

Science Conference Proceedings (OSTI)

This chapter provides a comprehensive review of the EPIC model in relation to carbon cycle, greenhouse-gas mitigation, and biofuel applications. From its original capabilities and purpose (i.e., quantify the impacts or erosion on soil productivity), the EPIC model has evolved into a comprehensive terrestrial ecosystem model for simulating with more or less process-level detail many ecosystem processes such as weather, hydrology, plant growth and development, carbon cycle (including erosion), nutrient cycling, greenhouse-gas emissions, and the most complete set of manipulations that can be implemented on a parcel of land (e.g. tillage, harvest, fertilization, irrigation, drainage, liming, burning, pesticide application). The chapter also provides details and examples of the latest efforts in model development such as the coupled carbon-nitrogen model, a microbial denitrification model with feedback to the carbon decomposition model, updates on calculation of ecosystem carbon balances, and carbon emissions from fossil fuels. The chapter has included examples of applications of the EPIC model in soil carbon sequestration, net ecosystem carbon balance, and biofuel studies. Finally, the chapter provides the reader with an update on upcoming improvements in EPIC such as the additions of modules for simulating biochar amendments, sorption of soluble C in subsoil horizons, nitrification including the release of N2O, and the formation and consumption of methane in soils. Completion of these model development activities will render an EPIC model with one of the most complete representation of biogeochemical processes and capable of simulating the dynamic feedback of soils to climate and management in terms not only of transient processes (e.g., soil water content, heterotrophic respiration, N2O emissions) but also of fundamental soil properties (e.g. soil depth, soil organic matter, soil bulk density, water limits).

Izaurralde, Roberto C.; Mcgill, William B.; Williams, J.R.

2012-06-01T23:59:59.000Z

156

Determining the focal mechanisms of earthquakes by full waveform modeling  

E-Print Network (OSTI)

Determining the focal mechanism of an earthquake helps us to better characterize reservoirs, define faults, and understand the stress and strain regime. The objective of this thesis is to find the focal mechanism and depth ...

Busfar, Hussam A. (Hussam Abdullah)

2009-01-01T23:59:59.000Z

157

Finite Element Modelling and Molecular Dynamic Simulations of Carbon nanotubes/ Polymer Composites  

E-Print Network (OSTI)

Modeling of single-walled carbon nanotubes, multi-walled nanotubes and nanotube reinforced polymer composites using both the Finite Element method and the Molecular Dynamic simulation technique is presented. Nanotubes subjected to mechanical loading have been analyzed. Elastic moduli and thermal coefficient of expansion are calculated and their variation with diameter and length is investigated. In particular, the nanotubes are modeled using 3D elastic beam finite elements with six degrees of freedom at each node. The difficulty in modeling multi walled nanotubes is the van der Waal's forces between adjacent layers which are geometrically non linear in nature. These forces are modeled using truss elements. The nanotube-polymer interface in a nano-composite is modeled on a similar basis. While performing the molecular dynamic simulations, the geometric optimization is performed initially to obtain the minimized configuration and then the desired temperature is attained by rescaling the velocities of carbon atoms in the nanotube. Results show that the Young's modulus increases with tube diameter in molecular mechanics whereas decreases in molecular dynamics since the inter-atomic potential due to chemical reactions between the atoms is taken into consideration in molecular dynamics unlike in molecular mechanics.

Gaddamanugu, Dhatri

2009-05-01T23:59:59.000Z

158

Past and Future Effects of Ozone on Net Primary Production and Carbon Sequestration Using a Global Biogeochemical Model  

E-Print Network (OSTI)

Exposure of plants to ozone inhibits photosynthesis and therefore reduces vegetation production and carbon sequestration. Simulations with the Terrestrial Ecosystem Model (TEM) for the historical period (1860-1995) show ...

Felzer, Benjamin Seth.

159

Multiple-Century Response of a Coupled Ocean-Atmosphere Model to an Increase of Atmospheric Carbon Dioxide  

Science Conference Proceedings (OSTI)

To speculate on the future change of climate over several centuries, three 500-year integrations of a coupled ocean-atmosphere model were performed. In addition to the standard integration in which the atmospheric concentration of carbon dioxide ...

Syukuro Manabe; Ronald J. Stouffer

1994-01-01T23:59:59.000Z

160

A PKN Hydraulic Fracture Model Study and Formation Permeability Determination  

E-Print Network (OSTI)

Hydraulic fracturing is an important method used to enhance the recovery of oil and gas from reservoirs, especially for low permeability formations. The distribution of pressure in fractures and fracture geometry are needed to design conventional and unconventional hydraulic fracturing operations, fracturing during water-flooding of petroleum reservoirs, shale gas, and injection/extraction operation in a geothermal reservoir. Designing a hydraulic fracturing job requires an understanding of fracture growth as a function of treatment parameters. There are various models used to approximately define the development of fracture geometry, which can be broadly classified into 2D and 3D categories. 2D models include, the Perkins-Kern-Nordgren (PKN) fracture model, and the Khristianovic-Geertsma-de. Klerk (KGD) fracture model, and the radial model. 3D models include fully 3D models and pseudo-three-dimensional (P-3D) models. The P-3D model is used in the oil industry due to its simplification of height growth at the wellbore and along the fracture length in multi-layered formations. In this research, the Perkins-Kern-Nordgren (PKN) fracture model is adopted to simulate hydraulic fracture propagation and recession, and the pressure changing history. Two different approaches to fluid leak-off are considered, which are the classical Carter's leak-off theory with a constant leak-off coefficient, and Pressure-dependent leak-off theory. Existence of poroelastic effect in the reservoir is also considered. By examining the impact of leak-off models and poroelastic effects on fracture geometry, the influence of fracturing fluid and rock properties, and the leak-off rate on the fracture geometry and fracturing pressure are described. A short and wide fracture will be created when we use the high viscosity fracturing fluid or the formation has low shear modulus. While, the fracture length, width, fracturing pressure, and the fracture closure time increase as the fluid leak-off coefficient is decreased. In addition, an algorithm is developed for the post-fracture pressure-transient analysis to calculate formation permeability. The impulse fracture pressure transient model is applied to calculate the formation permeability both for the radial flow and linear fracture flow assumption. Results show a good agreement between this study and published work.

Xiang, Jing

2011-12-01T23:59:59.000Z

Note: This page contains sample records for the topic "determination modeling carbon" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


161

A Simple Model for Determination of Grain Boundary Potential from ...  

Science Conference Proceedings (OSTI)

The model predicts that I-V dependence has two linear regions, at very low and very high voltages, and a transition region, within which the current increases by  ...

162

Climate Determinism Revisited: Multiple Equilibria in a Complex Climate Model  

E-Print Network (OSTI)

Multiple equilibria in a coupled ocean–atmosphere–sea ice general circulation model (GCM) of an aquaplanet with many degrees of freedom are studied. Three different stable states are found for exactly the same set of ...

Ferreira, David

163

What Determines Meridional Heat Transport in Climate Models?  

Science Conference Proceedings (OSTI)

The annual mean maximum meridional heat transport (MHTMAX) differs by approximately 20% among coupled climate models. The value of MHTMAX can be expressed as the difference between the equator-to-pole contrast in absorbed solar radiation (ASR*) ...

Aaron Donohoe; David S. Battisti

2012-06-01T23:59:59.000Z

164

Climate Determinism Revisited: Multiple Equilibria in a Complex Climate Model  

Science Conference Proceedings (OSTI)

Multiple equilibria in a coupled ocean–atmosphere–sea ice general circulation model (GCM) of an aquaplanet with many degrees of freedom are studied. Three different stable states are found for exactly the same set of parameters and external ...

David Ferreira; John Marshall; Brian Rose

2011-02-01T23:59:59.000Z

165

Transient Response of the Hadley Centre Coupled Ocean-Atmosphere Model to Increasing Carbon Dioxide. Part III: Analysis of Global-Mean Response Using Simple Models  

Science Conference Proceedings (OSTI)

The roles of surface, atmospheric, and oceanic feedbacks in controlling the global-mean transient response of a coupled ocean-atmosphere general circulation model to increasing carbon dioxide are investigated. The analysis employs a four-box ...

J. M. Murphy

1995-03-01T23:59:59.000Z

166

The carbon disclosure project, an evolution in international environmental corporate governance : motivations and determinants of market response to voluntary disclosures.  

E-Print Network (OSTI)

??This paper examines the factors associated with Canadian firms voluntarily disclosing climate change information through the Carbon Disclosure Project. Five hypotheses are presented to explain… (more)

Wegener, Matt

2010-01-01T23:59:59.000Z

167

Kalman filter model for determining block and trickle SNM losses  

Science Conference Proceedings (OSTI)

This paper describes an integrated decision procedure for deciding whether a diversion of SNM has occurred. Two possible types of diversion are considered: a block loss during a single time period and a cumulative trickle loss over several time periods. The methodology used is based on a compound Kalman filter model. Numerical examples will illustrate our approach.

Barlow, R.E.; Durst, M.J.; Smiriga, N.G.

1982-04-20T23:59:59.000Z

168

The Transportation Revenue Estimator and Needs Determination System (TRENDS) Model  

E-Print Network (OSTI)

.......................................................... 15 3.3 Indexing the Motor Fuels Tax, inflation rates, taxes, fees and other elements. The output is a set of tables and graphs showing a forecast................................................................................................. 12 TRENDS Model Revenue Enhancements Tab 3.1 State Gasoline and Diesel Fuel Variables

169

Performance characteristics and modeling of carbon dioxide absorption by amines in a packed column  

Science Conference Proceedings (OSTI)

Carbon dioxide (CO[sub 2]) is widely recognized as a major greenhouse gas contributing to global warming. To mitigate the global warming problem, removal of CO[sub 2] from the industrial flue gases is necessary. Absorption of carbon dioxide by amines in a packed column was experimentally investigated. The amines employed in the present study were the primary mono-ethanolamine (MEA) and tertiary N-methyldiethanolamine (MDEA), two very popular amines widely used in the industries for gas purification. The CO[sub 2] absorption characteristics by these two amines were experimentally examined under various operating conditions. A theoretical model was developed for describing the CO[sub 2] absorption behavior. Test data have revealed that the model predictions and the observed CO[sub 2] absorption breakthrough curves agree very well, validating the proposed model. Preliminary regeneration tests of exhausted amine solution were also conducted. The results indicated that the tertiary amine is easier to regenerate with less loss of absorption capacity than the primary one.

Lin, S.H.; Shyu, C.T. (Yuan Ze Univ., Taoyuan (Taiwan, Province of China). Dept. of Chemical Engineering)

1999-01-01T23:59:59.000Z

170

Determination of Extratropical Tropopause Height in an Idealized Gray Radiation Model  

Science Conference Proceedings (OSTI)

This paper investigates the mechanisms that determine the extratropical tropopause height, extending previous results with a Newtonian cooling model. A primitive equation model forced by a meridional gradient of incoming solar radiation, with the ...

Pablo Zurita-Gotor; Geoffrey K. Vallis

2013-07-01T23:59:59.000Z

171

Determination of Semivariogram Models to Krige Hourly and Daily Solar Irradiance in Western Nebraska  

Science Conference Proceedings (OSTI)

In this paper, linear and spherical semivariogram models were determined for use in kriging hourly and daily solar irradiation for every season of the year. The data used to generate the models were from 18 weather stations in western Nebraska. ...

G. G. Merino; D. Jones; D. E. Stooksbury; K. G. Hubbard

2001-06-01T23:59:59.000Z

172

A model for matrix acidizing of long horizontal well in carbonate reservoirs  

E-Print Network (OSTI)

Horizontal wells are drilled to achieve improved reservoir coverage, high production rates, and to overcome water coning problems, etc. Many of these wells often produce at rates much below the expected production rates. Low productivity of horizontal wells is attributed to various factors such as drilling induced formation damage, high completion skins, and variable formation properties along the length of the wellbore as in the case of heterogeneous carbonate reservoirs. Matrix acidizing is used to overcome the formation damage by injecting the acid into the carbonate rock to improve well performance. Designing the matrix acidizing treatments for horizontal wells is a challenging task because of the complex process. The estimation of acid distribution along wellbore is required to analyze that the zones needing stimulation are receiving enough acid. It is even more important in cases where the reservoir properties are varying along the length of the wellbore. A model is developed in this study to simulate the placement of injected acid in a long horizontal well and to predict the subsequent effect of the acid in creating wormholes, overcoming damage effects, and stimulating productivity. The model tracks the interface between the acid and the completion fluid in the wellbore, models transient flow in the reservoir during acid injection, considers frictional effects in the tubulars, and predicts the depth of penetration of acid as a function of the acid volume and injection rate at all locations along the completion. A computer program is developed implementing the developed model. The program is used to simulate hypothetical examples of acid placement in a long horizontal section. A real field example of using the model to history match actual treatment data from a North Sea chalk well is demonstrated. The model will help to optimize acid stimulation in horizontal wells.

Mishra, Varun

2007-08-01T23:59:59.000Z

173

Carbon nanotubes in almost homogeneous transverse magnetic field: exactly solvable model  

E-Print Network (OSTI)

Single-wall carbon nanotubes are considered in the presence of an external magnetic field with inhomogeneous transverse component. The continuum model is employed where the dynamics of the charge carriers is governed by the Dirac-Weyl equation. It is shown that a small fluctuation of the transverse field around a constant value represented by a finite-gap vector potential provides exact solutions of the stationary equation. An example is elaborated in detail. The spectrum of the system manifests remarkable stability with respect to small perturbations of the longitudinal momentum. Nonlinear, N=2 supersymmetry associated with the metallic and the maximally semi-conducting nanotubes is discussed.

Vit Jakubsky; Sengul Kuru; Javier Negro

2013-06-10T23:59:59.000Z

174

General Equilibrium, Electricity Generation Technologies and the Cost of Carbon Abatement  

E-Print Network (OSTI)

Electricity generation is a major contributor to carbon dioxide emissions, and a key determinant of abatement costs. Ex-ante assessments of carbon policies mainly rely on either of two modeling paradigms: (i) partial ...

Lanz, Bruno, 1980-

175

EVALUATING THE LAND AND OCEAN COMPONENTS OF THE GLOBAL CARBON CYCLE IN THE CMIP5 EARTH SYSTEM MODELS  

Science Conference Proceedings (OSTI)

We assess the ability of 18 Earth System Models to simulate the land and ocean carbon cycle for the present climate. These models will be used in the next Intergovernmental Panel on Climate Change (IPCC) Fifth Assessment Report (AR5) for climate ...

A. Anav; P. Friedlingstein; M. Kidston; L. Bopp; P. Ciais; P. Cox; C. Jones; M. Jung; R. Myneni; Z. Zhu

176

Evaluating the Land and Ocean Components of the Global Carbon Cycle in the CMIP5 Earth System Models  

Science Conference Proceedings (OSTI)

The authors assess the ability of 18 Earth system models to simulate the land and ocean carbon cycle for the present climate. These models will be used in the next Intergovernmental Panel on Climate Change (IPCC) Fifth Assessment Report (AR5) for ...

A. Anav; P. Friedlingstein; M. Kidston; L. Bopp; P. Ciais; P. Cox; C. Jones; M. Jung; R. Myneni; Z. Zhu

2013-09-01T23:59:59.000Z

177

CX-000459: Categorical Exclusion Determination | Department of...  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

9: Categorical Exclusion Determination CX-000459: Categorical Exclusion Determination Molecular Simulation of Dissolved Inorganic Carbons for Underground Brine Carbon Dioxide...

178

A model to determine financial indicators for organic solar cells  

Science Conference Proceedings (OSTI)

Organic solar cells are an emerging photovoltaic technology that is inexpensive and easy to manufacture, despite low efficiency and stability. A model, named TEEOS (Technical and Economic Evaluator for Organic Solar), is presented that evaluates organic solar cells for various solar energy applications in different geographic locations, in terms of two financial indicators, payback period and net present value (NPV). TEEOS uses SMARTS2 software to estimate broadband (280-4000 nm) spectral irradiance data and with the use of a cloud modification factor, predicts hourly irradiation in the absence of actual broadband irradiance data, which is scarce for most urban locations. By using the avoided cost of electricity, annual savings are calculated which produce the financial indicators. It is hoped that these financial indicators can help guide certain technical decisions regarding the direction of research for organic solar cells, for example, increasing efficiency or increasing the absorptive wavelength range. A sample calculation using solar hats is shown to be uneconomical, but a good example of large-scale organic PV production. (author)

Powell, Colin; Bender, Timothy; Lawryshyn, Yuri [Department of Chemical Engineering and Applied Chemistry, Faculty of Engineering and Applied Science, University of Toronto, 200 College Street, Toronto, Ont. (Canada)

2009-11-15T23:59:59.000Z

179

A Model-Based Approach for Determining Orientations of Biological Macromolecules Imaged by Cryoelectron Microscopy  

E-Print Network (OSTI)

-ray crystallographic 3D model; X174, bac- teriophage X174; X174PV, bacteriophage X174 provirion; X174PC, bacteriophageA Model-Based Approach for Determining Orientations of Biological Macromolecules Imaged-dimensional density map serves as a high signal-to-noise model from which a PFT database of different views

Baker, Timothy S.

180

Modeling polychlorinated biphenyl mass transfer after amendment of contaminated sediment with activated carbon  

SciTech Connect

The sorption kinetics and concentration of polychlorinated biphenyls (PCBs) in historically polluted sediment is modeled to assess a remediation strategy based on in situ PCB sequestration by mixing with activated carbon (AC). The authors extend their evaluation of a model based on intraparticle diffusion by including a biomimetic semipermeable membrane device (SPMD) and a first-order degradation rate for the aqueous phase. The model predictions are compared with the previously reported experimental PCB concentrations in the bulk water phase and in SPMDs. The simulated scenarios comprise a marine and a freshwater sediment, four PCB congeners, two AC grain sizes, four doses of AC, and comparison with laboratory experiments. The modeling approach distinguishes between two different sediment particles types: a light-density fraction representing carbonaceous particles such as charcoal, coal, coke, cenospheres, or wood, and a heavy-density fraction representing the mineral phase with coatings of organic matter. A third particle type in the numerical model is AC. The model qualitatively reproduces the observed shifts in the PCB distribution during repartitioning after AC amendment but overestimates the overall effect of the treatment in reducing aqueous and SPMD concentrations of PCBs by a factor of 2-6. For the AC application in sediment, competitive sorption of the various solutes apparently requires a reduction by a factor of 16 of the literature values for the AC-water partitioning coefficient measured in pure aqueous systems. With this correction, model results and measurements agree within a factor of 3. After AC amendment is homogeneously mixed into the sediment and then left undisturbed, aqueous PCB concentrations tend toward the same reduction after 5 years. 19 refs., 5 figs., 4 tabs.

David Werner; Upal Ghosh; Richard G. Luthy [University of Newcastle upon Tyne, Newcastle (United Kingdom)

2006-07-01T23:59:59.000Z

Note: This page contains sample records for the topic "determination modeling carbon" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


181

Electrostatic Precipitator Performance Modeling of High Carbon Ash Using EPRI's ESPM  

Science Conference Proceedings (OSTI)

To meet reduced nitrogen oxide (NOX) emission limits, many power producers installed low-NOX combustion systems that raised the level of carbon in the ash. However, carbon can be difficult to collect in an electrostatic precipitator and, consequently, the particulate emissions from many affected units increased. EPRI initiated this study to better understand carbon capture in electrostatic precipitators (ESPs), improve collection of high carbon ashes, and predict the collection of such ashes with its ESP...

2007-03-19T23:59:59.000Z

182

A Generative Model for Statistical Determination of Information Content from Conversation Threads  

Science Conference Proceedings (OSTI)

We present a generative model for determining the information content of a message without analyzing the message content. Such a tool is useful for automated analysis of the vast contents of online communication which are extensively contaminated by ...

Yingjie Zhou; Malik Magdon-Ismail; William A. Wallace; Mark Goldberg

2008-06-01T23:59:59.000Z

183

Modeling of a greenhouse equipped with a solar rockbed system and with carbon dioxide enrichment  

SciTech Connect

Various ways of greenhouse environmental modification, energy conservation, solar collection, and energy storage and utilization were investigated to utilize the available solar energy more efficiently. A computer simulation model describing the greenhouse thermal behavior was developed and programmed for a greenhouse with a solar rockbed system to evaluate numerous energy conservation designs. Validation of the model was made based on the measured greenhouse performance data sets obtained from a prototype greenhouse. For validation, eight periods were chosen to encompass a wide range of prevailing weather and environmental conditions inside the greenhouse. The accuracy of the values predicted by this model was very high. Based on the developed model, a sensitivity analysis was made to determine the effect of key parameters on certain simulated results. Generally, the key parameters related with the greenhouse environmental modifications showed high sensitivities.

Suh, W.M.

1986-01-01T23:59:59.000Z

184

CUFR Tree Carbon Calculator | Open Energy Information  

Open Energy Info (EERE)

CUFR Tree Carbon Calculator CUFR Tree Carbon Calculator Jump to: navigation, search Tool Summary LAUNCH TOOL Name: CUFR Tree Carbon Calculator Agency/Company /Organization: United States Forest Service Sector: Climate, Land Focus Area: Forestry Phase: Determine Baseline, Evaluate Options Topics: GHG inventory, Resource assessment Resource Type: Software/modeling tools User Interface: Desktop Application Website: www.fs.fed.us/ccrc/topics/urban-forests/ctcc/ Cost: Free Language: English References: CUFR Tree Carbon Calculator[1] Overview "The CUFR Tree Carbon Calculator is the only tool approved by the Climate Action Reserve's Urban Forest Project Protocol for quantifying carbon dioxide sequestration from GHG tree planting projects. The CTCC is programmed in an Excel spreadsheet and provides carbon-related information

185

A comparison of two data analysis techniques and their applications for modeling the carbon dioxide capture process  

Science Conference Proceedings (OSTI)

Improving the efficiency of the carbon dioxide (CO"2) capture process requires a good understanding of the intricate relationships among parameters involved in the process. The objective of this research is to study the nature of relationships among ... Keywords: CO2 capture process, Data modeling, Neural network, Sensitivity analysis, Statistical analysis

Yuxiang Wu; Qing Zhou; Christine W. Chan

2010-12-01T23:59:59.000Z

186

Modeling and Optimization of Matrix Acidizing in Horizontal Wells in Carbonate Reservoirs  

E-Print Network (OSTI)

In this study, the optimum conditions for wormhole propagation in horizontal well carbonate acidizing was investigated numerically using a horizontal well acidizing simulator. The factors that affect the optimum conditions are rock mineralogy, acid concentration, temperature and acid flux in the formation. The work concentrated on the investigation of the acid flux. Analytical equations for injection rate schedule for different wormhole models. In carbonate acidizing, the existence of the optimum injection rate for wormhole propagation has been confirmed by many researchers for highly reactive acid/rock systems in linear core-flood experiments. There is, however, no reliable technique to translate the laboratory results to the field applications. It has also been observed that for radial flow regime in field acidizing treatments, there is no single value of acid injection rate for the optimum wormhole propagation. In addition, the optimum conditions are more difficult to achieve in matrix acidizing long horizontal wells. Therefore, the most efficient acid stimulation is only achieved with continuously increasing acid injection rates to always maintain the wormhole generation at the tip of the wormhole at its optimum conditions. Examples of acid treatments with the increasing rate schedules were compared to those of the single optimum injection rate and the maximum allowable rate. The comparison study showed that the increasing rate treatments had the longest wormhole penetration and, therefore, the least negative skin factor for the same amount of acid injected into the formations. A parametric study was conducted for the parameters that have the most significant effects on the wormhole propagation conditions such as injected acid volume, horizontal well length, acid concentration, and reservoir heterogeneity. The results showed that the optimum injection rate per unit length increases with increasing injected acid volume. And it was constant for scenarios with different lateral lengths for a given system of rock/ acid and injected volume. The study also indicated that for higher acid concentration the optimum injection rate was lower. It does exist for heterogeneous permeability formations. Field treatment data for horizontal wells in Middle East carbonate reservoirs were also analyzed for the validation of the numerical acidizing simulator.

Tran, Hau

2013-05-01T23:59:59.000Z

187

Determining Key Model Parameters of Rapidly Intensifying Hurricane Guillermo (1997) Using the Ensemble Kalman Filter  

Science Conference Proceedings (OSTI)

In this work the authors determine key model parameters for rapidly intensifying Hurricane Guillermo (1997) using the ensemble Kalman filter (EnKF). The approach is to utilize the EnKF as a tool only to estimate the parameter values of the model ...

Humberto C. Godinez; Jon M. Reisner; Alexandre O. Fierro; Stephen R. Guimond; Jim Kao

2012-11-01T23:59:59.000Z

188

Using modeling to design and evaluate transient open ocean iron enrichment for carbon sequestration  

NLE Websites -- All DOE Office Websites (Extended Search)

Using modeling to design and evaluate Using modeling to design and evaluate transient open ocean iron enrichment for carbon sequestration Richard T. Barber (rbarber@duke.edu; 252-504-7578) Duke University Marine Laboratory 135 Duke Marine Lab Road Beaufort, NC 28516-9721 Fei Chai (fchai@maine.edu; 207-581-4317) University of Maine School of Marine Sciences 5741 Libby Hall Orono, ME 04469-5741 Introduction During the 1990s the rate of increase of CO 2 in the atmosphere was about 3.5 Pg C y -1 . Total emissions were 7.4 Pg C y -1 , so about 3.9 Pg C y -1 (52% of total emissions) were sequestered naturally. Of this, about 2.2 Pg C y -1 was absorbed by the oceans and 1.7 Pg C y -1 by the land (US DOE, 1999). The Kyoto Protocol of 1997 calls for a 34% reduction of emissions by 2050 and a reduction of 70% from the projected emissions at 2100. The major approach to

189

Plasmachemical Synthesis of Carbon Suboxide  

E-Print Network (OSTI)

A nonthermal carbon monoxide plasma is known to produce a solid deposition which is thought to be a polymer of carbon suboxide (C3O2); however there are very few investigations of this deposition in the literature. This thesis contains an analysis of the theoretical thermodynamics and kinetics of carbon suboxide formation as well as experimental results. The theoretical analysis suggests that carbon suboxide may be an equilibrium product even at ambient conditions but favors lower temperatures; furthermore if solid carbon is considered to be kinetically limited, and therefore not a product, then carbon suboxide is more likely to be a product under these pseudo-equilibrium conditions. Experimentally, solid films were produced in a dielectric barrier discharge (DBD) containing pure carbon monoxide. Optical emission spectroscopy was used to analyze the plasma and models of the emission spectra were created to determine the plasma temperatures. Deposition rates were determined to be on the order of 0.2 mg/min at a power of about 10W; it is expected however that these conditions are not optimized. The overall kinetics of carbon suboxide was analyzed and optimal conditions for operation can be estimated. Characterization of the solid depositions were carried out using Solid State Nuclear Magnetic Resonance (NMR), Fourier Transform Infrared Spectroscopy (FTIR), Electrospray Ionization Mass Spectroscopy (ESI-MS), and Matrix-assisted Laser Desorption Ionization Mass Spectroscopy (MALDI-MS). The characteristics of the film are very comparable to hydrolyzed carbon suboxide polymer suggesting that carbon suboxide polymer were in fact created in the carbon monoxide plasma at atmospheric conditions.

Geiger, Robert

2013-05-01T23:59:59.000Z

190

GFDL’s ESM2 Global Coupled Climate–Carbon Earth System Models. Part I: Physical Formulation and Baseline Simulation Characteristics  

Science Conference Proceedings (OSTI)

The physical climate formulation and simulation characteristics of two new global coupled carbon–climate Earth System Models, ESM2M and ESM2G, are described. These models demonstrate similar climate fidelity as the Geophysical Fluid Dynamics ...

John P. Dunne; Jasmin G. John; Alistair J. Adcroft; Stephen M. Griffies; Robert W. Hallberg; Elena Shevliakova; Ronald J. Stouffer; William Cooke; Krista A. Dunne; Matthew J. Harrison; John P. Krasting; Sergey L. Malyshev; P. C. D. Milly; Peter J. Phillipps; Lori T. Sentman; Bonita L. Samuels; Michael J. Spelman; Michael Winton; Andrew T. Wittenberg; Niki Zadeh

2012-10-01T23:59:59.000Z

191

Carbon Dioxide Adsorption by Metal Organic Frameworks (Synthesis, Testing and Modeling).  

E-Print Network (OSTI)

??It is essential to capture carbon dioxide from flue gas because it is considered one of the main causes of global warming. Several materials and… (more)

Sabouni, Rana

2013-01-01T23:59:59.000Z

192

Detection of long-term trends in carbon accumulation by forests in Northeastern U. S. and determination of causal factors: Final report  

Science Conference Proceedings (OSTI)

The overall project goal was to quantify the trends and variability for Net ecosystem exchange of CO{sub 2}, H{sub 2}O, and energy by northeastern forests, with particular attention to the role of succession, differences in species composition, legacies of past land use, and disturbances. Measurements included flux measurements and observations of biomass accumulation using ecosystem modeling as a framework for data interpretation. Continuation of the long-term record at the Environmental Measurement Site (EMS) Tower was a priority. The final quality-assured CO{sub 2}-flux data now extend through 2010. Data through 2011 are collected but not yet finalized. Biomass observations on the plot array centered on the tower are extended to 2011. Two additional towers in a hemlock stand (HEM) and a younger deciduous stand (LPH) complement the EMS tower by focusing on stands with different species composition or age distribution and disturbance history, but comparable climate and soil type. Over the period since 1993 the forest has added 24.4 Mg-C ha{sup -1} in the living trees. Annual net carbon uptake had been increasing from about 2 Mg-C ha{sup -1}y{sup -1} in the early 1990s to nearly 6 Mg-C ha{sup -1}y{sup -1} by 2008, but declined in 2009-2010. We attribute the increasing carbon uptake to a combination of warmer temperatures, increased photosynthetic efficiency, and increased influence by subcanopy hemlocks that are active in the early spring and late autumn when temperatures are above freezing but the deciduous canopy is bare. Not all of the increased carbon accumulation was found in woody biomass. Results from a study using data to optimize parameters in an ecosystem process model indicate that significant changes in model parameters for photosynthetic capacity and shifts in allocation to slow cycling soil organic matter are necessary for the model to match the observed trends. The emerging working hypothesis is that the pattern of increasing carbon uptake over the early 2000's represents a transient pulse that will eventually end as decomposition of the accumulated carbon catches up.

J. William Munger; Steven C. Wofsy; David R. Foster

2012-01-31T23:59:59.000Z

193

A model for determining the fate of hazardous constituents in waste during in-vessel composting  

E-Print Network (OSTI)

Composting is one of the techniques that has evolved as a safe disposal and predisposal alternative to the stringent regulations on hazardous waste disposal. The implementation of this technique needs careful evaluation of the processes a hazardous compound undergoes when subjected to composting. The purpose of this thesis is to define these processes and develop a model for determining the fate of organic compounds in waste during in-vessel composting Volatilization and biodegradation are found to be the major fate determining processes. Following mass balance approach the compound's loss through these processes is evaluated by developing a fate model. Fate of six aromatic compounds which fall into three categories-volatile, semi-volatile, and non volatile, is determined and the results compared to the experimental values for validating the model. A sensitivity analysis has been performed to determine which parameters most influence the model behavior and quantitatively describe their effects on model performance. The results obtained from the model show close agreement with the experimental results. More data is required to quantify the slight differences observed. The volatilization loss is found to exist only for first few hours. Biodegradation rates are found to have very little impact on volatilization of the compound. Air flow rate and volume of the waste are found to have a noticeable effect on the volatilization of a compound. Bulk density is found to effect volatilization to a small extent. Air quality control measures are recommended for the first few days to deal with the volatilized gases.

Bollineni, Prasanthi

1994-01-01T23:59:59.000Z

194

Estimating the uncertainty of modeled carbon sequestration: The GreenCertTM system  

Science Conference Proceedings (OSTI)

The GreenCert(TM) system was developed to help farm and ranch owners to quantify, standardize, pool and market CO"2 emissions offset (sequestration) credits derived from improved rangeland or cropland management. It combines a user-friendly interface ... Keywords: C-LOCK®, CENTURY, Carbon sequestration, GreenCertTM, Monte Carlo, Sensitivity, Soil carbon

Karen Updegraff; Patrick R. Zimmerman; Patrick Kozak; Ding-Geng Chen; Maribeth Price

2010-12-01T23:59:59.000Z

195

Ab-initio molecular modeling of interfaces in tantalum-carbon system  

Science Conference Proceedings (OSTI)

Processing of ultrahigh temperature TaC ceramic material with sintering additives of B{sub 4}C and reinforcement of carbon nanotubes (CNTs) gives rise to possible formation of several interfaces (Ta{sub 2}C-TaC, TaC-CNT, Ta{sub 2}C-CNT, TaB{sub 2}-TaC, and TaB{sub 2}-CNT) that could influence the resultant properties. Current work focuses on interfaces developed during spark plasma sintering of TaC-system and performing ab initio molecular modeling of the interfaces generated during processing of TaC-B{sub 4}C and TaC-CNT composites. The energy of the various interfaces has been evaluated and compared with TaC-Ta{sub 2}C interface. The iso-surface electronic contours are extracted from the calculations eliciting the enhanced stability of TaC-CNT interface by 72.2%. CNTs form stable interfaces with Ta{sub 2}C and TaB{sub 2} phases with a reduction in the energy by 35.8% and 40.4%, respectively. The computed Ta-C-B interfaces are also compared with experimentally observed interfaces in high resolution TEM images.

Balani, Kantesh; Mungole, Tarang [Materials Science and Engineering, Indian Institute of Technology, Kanpur-208016 (India); Bakshi, Srinivasa Rao [Mechanical and Materials Engineering, Florida International University, Miami, Florida 33174 (United States); Metallurgical and Materials Engineering, Indian Institute of Technology Madras, Chennai 600036 (India); Agarwal, Arvind [Mechanical and Materials Engineering, Florida International University, Miami, Florida 33174 (United States)

2012-03-15T23:59:59.000Z

196

Modeling the effects of topography and wind on atmospheric dispersion of CO2 surface leakage at geologic carbon sequestration sites  

E-Print Network (OSTI)

CO 2 from geologic carbon sequestration sites, Vadose Zoneleakage at geologic carbon sequestration sites Fotini K.assessment for geologic carbon sequestration sites. We have

Chow, Fotini K.

2009-01-01T23:59:59.000Z

197

Development of moving bed simulation model for carbon capture from fossil energy systems.  

Science Conference Proceedings (OSTI)

The capture and separation of carbon dioxide (CO2) has been identified as a high-priority topic to cope with global climate change. Fossil fuels currently supply the most of the world's energy needs, and their utilization is the major source of the anthropogenic CO2 emission [1]. Particularly, the existing coal-fired power plants annually emit about 2 billion tons of CO2 which is equivalent to two-thirds of the total emissions from U.S. power sector [2]. Therefore, it is critical to develop the cost-effective technologies to mitigate this problem. There are three options for capture for capturing CO2 from fossil energy system: post-combustion capture, pre-combustion capture, and oxy-combustion. Among them, post-combustion capture has the greatest near-term potential for reducing CO2 emission, because it can be applied to the existing coal-fired power plant with relative ease through a retrofit. The current commercially available solvent-based processes have advantages of fast kinetics and strong reactions, however only at a significant cost and efficiency penalty. Recently, various solid sorbents are being explored for one of promising CO2 capture technology, which are expected to reduce energy requirement and water usage with the approaches of fluidized or moving bed. However, solids are inherently more difficult to work with than liquids and no large scale system has yet been commercialized. In this study, we developed the rigorous 1-D PDE model for moving beds in Aspen Custom Modeler; the entire system consists of adsorbers, regenerators, and auxiliary equipment. The simulation result will be expected to compare with those of other post-combustion processes. We will deal with not only advantages of lower capital costs and power requirements but also problems associated with pressure drop and heat transfer.

Kim, H.; Miller, D.

2011-01-01T23:59:59.000Z

198

Development of dynamic models of reactive distillation columns for simulation and determination of control  

E-Print Network (OSTI)

Dynamic models of a reactive distillation column have been developed and implemented in this work. A model describing the steady state behavior of the system has been built in a first step. The results from this steady state model have been compared to data provided from an industrial collaborator and the reconciled model formed the basis for the development of a dynamic model. Four controlled and four manipulated variables have been determined in a subsequent step and step tests for the manipulated variables were simulated. The data generated by the step responses was used for fitting transfer functions between the manipulated and the controlled variables. RGA analysis was performed to find the optimal pairing for controller design. Feedback controllers of PID type were designed between the paired variables found from RGA and the controllers were implemented on the column model. Both servo and regulatory problems have been considered and tested.

Chakrabarty, Arnab

2004-12-01T23:59:59.000Z

199

DETERMINANTS OF FOREIGN DIRECT INVESTMENT IN IRAN: AN EMPIRICAL STUDY USING STRUCTURAL EQUATION MODELLING  

E-Print Network (OSTI)

Abstract. This paper examines the determinants of foreign direct investment (FDI) in Iran by applying the structural equation modelling (SEM). Using the annual time series data for the 1991-2006 period, two models were developed. In the first model the correlation between 12 determining factors and FDI in Iran were analyzed and in the second model the 12 factors were fit into five categories of determinants namely: Business, Economic, Infrastructural, Oil and Science and Technology and the impact of each of the mentioned groups of factors was investigated. The results derived through the first model indicated that openness of trade and Gross Domestic Product (GDP) per capita have a significant positive impact on FDI in Iran, while along with inflation, oil extraction and production had a surprisingly negative correlation with FDI. The results also suggested that infrastructural factors pertaining to telecommunications in addition to market size, research and development (R&D), education and the scientific output encourage FDI inflows in Iran. The second model output estimates revealed that the business factors promote FDI most and interestingly once more the oil factor proved to have a negative impact on the FDI inflows to Iran.

Ahmad Jafarnejad; Arash Golnam; Naderale Ebrahim

2009-01-01T23:59:59.000Z

200

Modeling the effects of topography and wind on atmospheric dispersion of CO2 surface leakage at geologic carbon sequestration sites  

Science Conference Proceedings (OSTI)

Understanding the potential impacts of unexpected surface releases of CO{sub 2} is an essential part of risk assessment for geologic carbon sequestration sites. We have extended a mesoscale atmospheric model to model dense gas dispersion of CO{sub 2} leakage. The hazard from CO{sub 2} leakage is greatest in regions with topographic depressions where the dense gas can pool. Simulation of dispersion in idealized topographies shows that CO{sub 2} can persist even under high winds. Simulation of a variety of topographies, winds, and release conditions allows the generation of a catalog of simulation results that can be queried to estimate potential impacts at actual geologic carbon sequestration sites.

Chow, Fotini K.; Granvold, Patrick W.; Oldenburg, Curtis M.

2008-11-01T23:59:59.000Z

Note: This page contains sample records for the topic "determination modeling carbon" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


201

Visual representation of carbon dioxide adsorption in a low-volatile bituminous coal molecular model  

Science Conference Proceedings (OSTI)

Carbon dioxide can be sequestered in unmineable coal seams to aid in mitigating global climate change, while concurrently CH{sub 4} can be desorbed from the coal seam and used as a domestic energy source. In this work, a previously constructed molecular representation was used to simulate several processes that occur during sequestration, such as sorption capacities of CO{sub 2} and CH{sub 4}, CO{sub 2}-induced swelling, contraction because of CH{sub 4} and water loss, and the pore-blocking role of moisture. This is carried out by calculating the energy minima of the molecular model with different amounts of CO{sub 2}, CH{sub 4}, and H{sub 2}O. The model used is large (>2000 atoms) and contains a molecular-weight distribution, so that it has the flexibility to be used by other researchers and for other purposes in the future. In the low-level molecular modeling presented here, it was anticipated that CO{sub 2} would be adsorbed more readily than CH{sub 4}, that swelling would be anisotropic, greater perpendicular to the bedding plane because of the rank of this coal, and finally, that, with the addition of moisture, CO{sub 2} capacity in the coal would be reduced. As expected with this high-rank coal, there was swelling when CO{sub 2} perturbed the structure of approximately 5%. It was found that, on the basis of the interconnected pore structure and molecular sizes, CO{sub 2} was able to access 12.4% more of the pore volume (as defined by helium) than CH{sub 4}, in the rigid molecular representation. With water as stationary molecules, mostly hydrogen bound to the coal oxygen functionality, pore access decreased by 5.1% of the pore volume for CO{sub 2} accessibility and 4.7% of the pore volume for CH{sub 4} accessibility. 36 refs., 12 figs., 1 tab.

Marielle R. Narkiewicz; Jonathan P. Mathews [Pennsylvania State University, University Park, PA (United States). Department of Energy and Minerals Engineering

2009-09-15T23:59:59.000Z

202

Carbon-nitrogen bond-forming reactions in supercritical and expanded-liquid carbon dioxide media : green synthetic chemistry with multiscale reaction and phase behavior modeling  

E-Print Network (OSTI)

The goal of this work was to develop a detailed understanding of carbon-nitrogen (C-N) bond-forming reactions of amines carried out in supercritical and expanded-liquid carbon dioxide (CO2) media. Key motivations behind ...

Ciccolini, Rocco P

2008-01-01T23:59:59.000Z

203

Simulation and sensitivity analysis of carbon storage and fluxes in the New Jersey Pinelands  

Science Conference Proceedings (OSTI)

A major challenge in modeling the carbon dynamics of vegetation communities is the proper parameterization and calibration of eco-physiological variables that are critical determinants of the ecosystem process-based model behavior. In this study, we ... Keywords: Carbon dynamics, Eddy covariance tower, Fire effects, GEP, NEE, The extended Fourier amplitude sensitivity test approach (EFAST), WxBGC model

Zewei Miao; Richard G. Lathrop, Jr.; Ming Xu; Inga P. La Puma; Kenneth L. Clark; John Hom; Nicholas Skowronski; Steve Van Tuyl

2011-09-01T23:59:59.000Z

204

OPTIMIZATION OF THE CATHODE LONG-TERM STABILITY IN MOLTEN CARBONATE FUEL CELLS: EXPERIMENTAL STUDY AND MATHEMATICAL MODELING  

DOE Green Energy (OSTI)

The dissolution of NiO cathodes during cell operation is a limiting factor to the successful commercialization of molten carbonate fuel cells (MCFCs). Lithium cobalt oxide coating onto the porous nickel electrode has been adopted to modify the conventional MCFC cathode which is believed to increase the stability of the cathodes in the carbonate melt. The material used for surface modification should possess thermodynamic stability in the molten carbonate and also should be electro catalytically active for MCFC reactions. Two approaches have been adopted to get a stable cathode material. First approach is the use of LiNi{sub 0.8}Co{sub 0.2}O{sub 2}, a commercially available lithium battery cathode material and the second is the use of tape cast electrodes prepared from cobalt coated nickel powders. The morphology and the structure of LiNi{sub 0.8}Co{sub 0.2}O{sub 2} and tape cast Co coated nickel powder electrodes were studied using scanning electron microscopy and X-Ray diffraction studies respectively. The electrochemical performance of the two materials was investigated by electrochemical impedance spectroscopy and polarization studies. A three phase homogeneous model was developed to simulate the performance of the molten carbonate fuel cell cathode. The homogeneous model is based on volume averaging of different variables in the three phases over a small volume element. The model gives a good fit to the experimental data. The model has been used to analyze MCFC cathode performance under a wide range of operating conditions.

Dr. Ralph E. White; Dr. Branko N. Popov

2002-04-01T23:59:59.000Z

205

Cathode response model and literature review of metal solubility in carbonates. Topical report  

DOE Green Energy (OSTI)

The research described in this report is intended to explain some of the aspects of molten carbonate fuel cell system. The research currently being investigated is an important part of MCFC performance development.

NONE

1994-12-01T23:59:59.000Z

206

Acoustic energy dissipation and thermalization in carbon nanotubes: Atomistic modeling and mesoscopic description  

E-Print Network (OSTI)

The exchange of energy between low-frequency mechanical oscillations and high-frequency vibrational modes in carbon nanotubes (CNTs) is a process that plays an important role in a range of dynamic phenomena involving the ...

Nicholson, David A.

207

Modeling and control of a silicon substrate heater for carbon nanotube growth experiments  

E-Print Network (OSTI)

The precision engineering research group at MIT is working on carbon nanotube growth experiments on silicon substrates and in microfabricated silicon devices, to try to produce improved bulk nanotube growth. For this thesis, ...

Held, David (David A.)

2005-01-01T23:59:59.000Z

208

Determining manufacturing parameters to suppress system variance using linear and non-linear models  

Science Conference Proceedings (OSTI)

Determining manufacturing parameters for a new product is fundamentally a difficult problem, because there has little suggestion information. There are several researches on this topic, and most of them focus on single specific model or the engineer's ... Keywords: Engineering problem, Manufacturing, TFT-LCD

Der-Chiang Li; Wen-Chih Chen; Chiao-Wen Liu; Che-Jung Chang; Chien-Chih Chen

2012-03-01T23:59:59.000Z

209

Thermally-aware modeling and performance evaluation for single-walled carbon nanotube-based interconnects for future high performance integrated circuits  

Science Conference Proceedings (OSTI)

Given the performance and reliability limits of conventional copper interconnects in the tens of nanometer regime, carbon-nanotube (CNT) based interconnects emerge as a potential reliable alternative for future high performance VLSI industry. In this ... Keywords: Carbon nanotube bundles, High performance interconnect, Thermal modeling

Amir Hosseini; Vahid Shabro

2010-10-01T23:59:59.000Z

210

Satellite-Based Modeling of the Carbon Fluxes in Mature Black Spruce Forests in Alaska: A Synthesis of the Eddy Covariance Data and Satellite Remote Sensing Data  

Science Conference Proceedings (OSTI)

Scaling up of observed point data to estimate regional carbon fluxes is an important issue in the context of the global terrestrial carbon cycle. In this study, the authors proposed a new model to scale up the eddy covariance data to estimate ...

Masahito Ueyama; Yoshinobu Harazono; Kazuhito Ichii

2010-10-01T23:59:59.000Z

211

OPTIMIZATION OF THE CATHODE LONG-TERM STABILITY IN MOLTEN CARBONATE FUEL CELLS: EXPERIMENTAL STUDY AND MATHEMATICAL MODELING  

DOE Green Energy (OSTI)

The dissolution of NiO cathodes during cell operation is a limiting factor to the successful commercialization of molten carbonate fuel cells (MCFCs). Lithium cobalt oxide coating onto the porous nickel electrode has been adopted to modify the conventional MCFC cathode which is believed to increase the stability of the cathodes in the carbonate melt. The material used for surface modification should possess thermodynamic stability in the molten carbonate and also should be electro catalytically active for MCFC reactions. Lithium Cobalt oxide was coated on Ni cathode by a sol-gel coating. The morphology and the LiCoO{sub 2} formation of LiCoO{sub 2} coated NiO was studied using scanning electron microscopy and X-Ray diffraction studies respectively. The electrochemical performance lithium cobalt oxide coated NiO cathodes were investigated with open circuit potential measurement and current-potential polarization studies. These results were compared to that of bare NiO. Dissolution of nickel into the molten carbonate melt was less in case of lithium cobalt oxide coated nickel cathodes. LiCoO{sub 2} coated on the surface prevents the dissolution of Ni in the melt and thereby stabilizes the cathode. Finally, lithium cobalt oxide coated nickel shows similar polarization characteristics as nickel oxide. Conventional theoretical models for the molten carbonate fuel cell cathode are based on the thin film agglomerate model. The principal deficiency of the agglomerate model, apart from the simplified pore structure assumed, is the lack of measured values for film thickness and agglomerate radius. Both these parameters cannot be estimated appropriately. Attempts to estimate the thickness of the film vary by two orders of magnitude. To avoid these problems a new three phase homogeneous model has been developed using the volume averaging technique. The model considers the potential and current variation in both liquid and solid phases. Using this approach, volume averaged concentrations of both gaseous and liquid phase reactants are obtained separately. The polarization characteristics of the electrode have been studied for different electrode parameters. The effect of different design parameters on the electrode performance has also been analyzed. Finally, the model has been used to analyze the impedance response of the MCFC cathode.

Dr. Ralph E. White; Dr. Branko N. Popov

2001-10-01T23:59:59.000Z

212

Modeling Coal Matrix Shrinkage and Differential Swelling with CO2 Injection for Enhanced Coalbed Methane Recovery and Carbon Sequestration Applications  

SciTech Connect

Matrix shrinkage and swelling can cause profound changes in porosity and permeability of coalbed methane reservoirs during depletion or when under CO{sub 2} injection processes, with significant implication for primary or enhanced methane recovery. Two models that are used to describe these effects are discussed. The first was developed by Advanced Resources International (ARI) and published in 1990 by Sawyer, et al. The second model was published by Palmer and Mansoori in 1996. This paper shows that the two provide equivalent results for most applications. However, their differences in formulation cause each to have relative advantages and disadvantages under certain circumstances. Specifically, the former appears superior for undersaturated coalbed methane reservoirs while the latter would be better if a case is found where matrix swelling is strongly disproportional to gas concentration. Since its presentation in 1996, the Palmer and Mansoori model has justifiably received much critical praise. However, the model developed by ARI for the COMET reservoir simulation program has been in use since 1990, and has significant advantages in certain settings. A review of data published by Levine in 1996 reveals that carbon dioxide causes a greater degree of coal matrix swelling compared to methane, even when measured on a unit of concentration basis. This effect is described in this report as differential swelling. Differential swelling may have important consequences for enhanced coalbed methane and carbon sequestration projects. To handle the effects of differential swelling, an extension to the matrix shrinkage and swelling model used by the COMET simulator is presented and shown to replicate the data of Levine. Preliminary field results from a carbon dioxide injection project are also presented in support of the extended model. The field evidence supports that considerable changes to coal permeability occur with CO{sub 2} injection, with significant implication for the design, implementation and performance of enhanced coalbed methane recovery and CO{sub 2} sequestration projects.

L. J. Pekot; S. R. Reeves

2002-03-31T23:59:59.000Z

213

Integrating Remote Sensing, Field Observations, and Models to Understand Disturbance and Climate Effects on the Carbon Balance of the West Coast U.S., Final Report  

SciTech Connect

As an element of NACP research, the proposed investigation is a two pronged approach that derives and evaluates a regional carbon (C) budget for Oregon, Washington, and California. Objectives are (1) Use multiple data sources, including AmeriFlux data, inventories, and multispectral remote sensing data to investigate trends in carbon storage and exchanges of CO2 and water with variation in climate and disturbance history; (2) Develop and apply regional modeling that relies on these multiple data sources to reduce uncertainty in spatial estimates of carbon storage and NEP, and relative contributions of terrestrial ecosystems and anthropogenic emissions to atmospheric CO2 in the region; (3) Model terrestrial carbon processes across the region, using the Biome-BGC terrestrial ecosystem model, and an atmospheric inverse modeling approach to estimate variation in rate and timing of terrestrial uptake and feedbacks to the atmosphere in response to climate and disturbance.

Beverly E. Law

2011-10-05T23:59:59.000Z

214

Nonlinearity of Carbon Cycle Feedbacks  

Science Conference Proceedings (OSTI)

Coupled climate–carbon models have shown the potential for large feedbacks between climate change, atmospheric CO2 concentrations, and global carbon sinks. Standard metrics of this feedback assume that the response of land and ocean carbon uptake ...

Kirsten Zickfeld; Michael Eby; H. Damon Matthews; Andreas Schmittner; Andrew J. Weaver

2011-08-01T23:59:59.000Z

215

DEVELOPMENT OF A VALIDATED MODEL FOR USE IN MINIMIZING NOx EMISSIONS AND MAXIMIZING CARBON UTILIZATION WHEN CO-FIRING BIOMASS WITH COAL  

DOE Green Energy (OSTI)

This is the sixth Quarterly Technical Report for DOE Cooperative Agreement No. DE-FC26-00NT40895. A statement of the project objectives is included in the Introduction of this report. Two additional biomass co-firing test burns were conducted during this quarter. In the first test (Test 10), up to 20% by weight dry hardwood sawdust and switchgrass was compiled with Galatia coal and injected through the dual-register burner. Galatia coal is a medium-sulfur Illinois Basin coal ({approx}1.0% S). The dual-register burner is a generic low-NO{sub x} burner that incorporates two independent wind boxes. In the second test (Test 11), regular ({approx}70% passing 200 mesh) and finely ground ({approx}90% passing 200 mesh) Pratt Seam coal was injected through the single-register burner to determine if coal grind affects NO{sub x} and unburned carbon emissions. The results of these tests are presented in this quarterly report. Significant progress has been made in implementing a modeling approach to combine reaction times and temperature distributions from computational fluid dynamic models of the pilot-scale combustion furnace with char burnout and chemical reaction kinetics to predict NO{sub x} emissions and unburned carbon levels in the furnace exhaust. No additional results of CFD modeling have been received as delivery of the Configurable Fireside Simulator is expected during the next quarter. Preparations are under way for continued pilot-scale combustion experiments with the single-register burner and a low-volatility bituminous coal. Some delays have been experienced in the acquisition and processing of biomass. Finally, a project review was held at the offices of Southern Research in Birmingham, on February 27, 2002.

Larry G. Felix; P. Vann Bush

2002-04-30T23:59:59.000Z

216

System dynamics modelling of product carbon footprint life cycles for collaborative green supply chains  

Science Conference Proceedings (OSTI)

Governments, environmental groups and industry associations are reducing greenhouse gas emissions to insure environmental sustainability. Manufacturing plays an important role in economic development but is a main cause of global warming since production ... Keywords: economic input–output life cycle assessment, mass customisation, product carbon footprint, system dynamics

AmyJ. C. Trappey; CharlesV. Trappey; Chih-Tung Hsiao; JerryJ. R. Ou; Chin-Tsung Chang

2012-10-01T23:59:59.000Z

217

VISION Model : description of model used to estimate the impact of highway vehicle technologies and fuels on energy use and carbon emissions to 2050.  

DOE Green Energy (OSTI)

The VISION model has been developed by the U.S. Department of Energy (DOE) to provide estimates of the potential energy use, oil use, and carbon emission impacts to 2050 of advanced light- and heavy-duty highway vehicle technologies and alternative fuels. DOE supports research of advanced transportation technologies (including fuels) and is frequently asked to provide estimates of the potential impacts of successful market penetration of these technologies, sometimes on a relatively quick-turnaround basis. VISION is a spreadsheet model in Microsoft Excel that can be used to respond rapidly to quick-turnaround requests, as well as for longer-term analyses. It uses vehicle survival and age-dependent usage characteristics to project total light and heavy vehicle stock, total vehicle miles of travel (VMT), and total energy use by technology and fuel type by year, given market penetration and vehicle energy efficiency assumptions developed exogenously. Total carbon emissions for on-highway vehicles by year are also estimated because life-cycle carbon coefficients for various fuels are included in VISION. VISION is not a substitute for the transportation component of the Energy Information Administration's (EIA's) National Energy Modeling System (NEMS). NEMS incorporates a consumer choice model to project market penetration of advanced vehicles and alternative fuels. The projections are made within the context of the entire U.S. economy. However, the NEMS model is difficult to use on a quick-turnaround basis and only makes projections to 2025. VISION complements NEMS with its relative ''user-friendliness'' and by extending the time frame of potential analysis. VISION has been used for a wide variety of purposes. For illustration, we have listed some of its most recent and current uses in Table 1.1. Figures 1.1-1.3 illustrate the results of some of those runs. These graphs are not actual model output, but they are based on model results. The main body of this report describes VISION's methodology and data sources. The methodology and data sources used in the light- and heavy-vehicle portions of the model are discussed separately. Some suggestions for future improvements to the model are made. Appendix A provides instructions on how to run the VISION model. Appendix B describes the procedure for updating the model with the latest EIA Annual Energy Outlook (AEO).

Singh, M.; Vyas, A.; Steiner, E.

2004-02-19T23:59:59.000Z

218

Modeling global atmospheric CO2 with improved emission inventories and CO2 production from the oxidation of other carbon species  

Science Conference Proceedings (OSTI)

The use of global three-dimensional (3-D) models with satellite observations of CO2 in inverse modeling studies is an area of growing importance for understanding Earth s carbon cycle. Here we use the GEOS-Chem model (version 8-02-01) CO2 mode with multiple modifications in order to assess their impact on CO2 forward simulations. Modifications include CO2 surface emissions from shipping (0.19 PgC yr 1), 3-D spatially-distributed emissions from aviation (0.16 PgC yr 1), and 3-D chemical production of CO2 (1.05 PgC yr 1). Although CO2 chemical production from the oxidation of CO, CH4 and other carbon gases is recognized as an important contribution to global CO2, it is typically accounted for by conversion from its precursors at the surface rather than in the free troposphere. We base our model 3-D spatial distribution of CO2 chemical production on monthly-averaged loss rates of CO (a key precursor and intermediate in the oxidation of organic carbon) and apply an associated surface correction for inventories that have counted emissions of CO2 precursors as CO2. We also explore the benefit of assimilating satellite observations of CO into GEOS-Chem to obtain an observation-based estimate of the CO2 chemical source. The CO assimilation corrects for an underestimate of atmospheric CO abundances in the model, resulting in increases of as much as 24% in the chemical source during May June 2006, and increasing the global annual estimate of CO2 chemical production from 1.05 to 1.18 Pg C. Comparisons of model CO2 with measurements are carried out in order to investigate the spatial and temporal distributions that result when these new sources are added. Inclusion of CO2 emissions from shipping and aviation are shown to increase the global CO2 latitudinal gradient by just over 0.10 ppm (3%), while the inclusion of CO2 chemical production (and the surface correction) is shown to decrease the latitudinal gradient by about 0.40 ppm (10%) with a complex spatial structure generally resulting in decreased CO2 over land and increased CO2 over the oceans. Since these CO2 emissions are omitted or misrepresented in most inverse modeling work to date, their implementation in forward simulations should lead to improved inverse modeling estimates of terrestrial biospheric fluxes.

Nassar, Ray [University of Toronto; Jones, DBA [University of Toronto; Suntharalingam, P [University of East Anglia, Norwich, United Kingdom; Chen, j. [University of Toronto; Andres, Robert Joseph [ORNL; Wecht, K. J. [Harvard University; Yantosca, R. M. [Harvard University; Kulawik, SS [Jet Propulsion Laboratory, Pasadena, CA; Bowman, K [Jet Propulsion Laboratory, Pasadena, CA; Worden, JR [Jet Propulsion Laboratory, Pasadena, CA; Machida, T [National Institute for Environmental Studies, Japan; Matsueda, H [Meteorological Research Institute, Japan

2010-01-01T23:59:59.000Z

219

Estimating the Permafrost-Carbon Climate Response in the CMIP5 Climate Models Using a Simplified Approach  

Science Conference Proceedings (OSTI)

Under climate change, thawing permafrost may cause a release of carbon, which has a positive feedback on the climate. The permafrost-carbon climate response (?PF) is the additional permafrost-carbon made vulnerable to decomposition per degree of ...

Eleanor J. Burke; Chris D. Jones; Charles D. Koven

2013-07-01T23:59:59.000Z

220

Modelling of light driven CO2 concentration gradient and photosynthetic carbon assimilation flux distribution at the chloroplast level  

E-Print Network (OSTI)

The steady state of the two-substance model of light driven carbon turnover for the photosynthetic CO2 assimilation rate is presented. The model is based on the nonlinear diffusion equation for a single chloroplast in the elliptical geometry by assuming light driven Ribulose-1,5-bisphosphate (RuBP) regeneration and CO2 assimilation reaction of carboxilation coupled with the photosynthetic sink strength. The detailed analysis of 3 -dimensional CO2 concentration and flux on the chloroplast level is made. It is shown that under intense light irradiation there exists a boundary layer of chloroplasts with a high value of CO2 assimilation flux. The presented simplified model can be used for the calculations and experimental estimations of the CO2 assimilation rate for environmental applications.

Jouravlev, M

2012-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "determination modeling carbon" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


221

OPTIMIZATION OF THE CATHODE LONG-TERM STABILITY IN MOLTEN CARBONATE FUEL CELLS: EXPERIMENTAL STUDY AND MATHEMATICAL MODELING  

DOE Green Energy (OSTI)

The dissolution of NiO cathodes during cell operation is a limiting factor to the successful commercialization of molten carbonate fuel cells (MCFCs). Microencapsulation of the NiO cathode has been adopted as a surface modification technique to increase the stability of NiO cathodes in the carbonate melt. The material used for surface modification should possess thermodynamic stability in the molten carbonate and also should be electro catalytically active for MCFC reactions. A simple first principles model was developed to understand the influence of exchange current density and conductivity of the electrode material on the polarization of MCFC cathodes. The model predictions suggest that cobalt can be used to improve the corrosion resistance of NiO cathode without affecting its performance. Cobalt was deposited on NiO cathode by electroless deposition. The morphology and thermal oxidation behavior of Co coated NiO was studied using scanning electron microscopy and thermal gravimetric analysis respectively. The electrochemical performance of cobalt encapsulated NiO cathodes were investigated with open circuit potential measurement and current-potential polarization studies. These results were compared to that of bare NiO. The electrochemical oxidation behavior of cobalt-coated electrodes is similar to that of the bare NiO cathode. Dissolution of nickel into the molten carbonate melt was less in case of cobalt encapsulated nickel cathodes. Co coated on the surface prevents the dissolution of Ni in the melt and thereby stabilizes the cathode. Finally, cobalt coated nickel shows similar polarization characteristics as nickel oxide. A similar surface modification technique has been used to improve the performance of the SS 304 current collectors used in MCFC cells. SS 304 was encapsulated with nanostructured layers of NiCo and NiMo by electroless deposition. The corrosion behavior of bare and surface modified SS 304 in molten carbonate under cathode gas atmosphere was investigated with cyclic voltammetry, open circuit potential studies, Tafel polarization, impedance analysis and atomic absorption spectroscopy. This study confirms that the presence of surface modification leads to the formation of complex scales with better barrier properties and electronic conductivity.

Dr. Ralph E. White

2000-09-30T23:59:59.000Z

222

CX-000432: Categorical Exclusion Determination | Department of...  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Determination CX-000432: Categorical Exclusion Determination Understanding the Impact of Carbon Dioxide Injection on the Subsurface Microbial Community in an Illinois Basin Carbon...

223

CX-001169: Categorical Exclusion Determination | Department of...  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Exclusion Determination CX-001169: Categorical Exclusion Determination Pre-Combustion Carbon Dioxide Capture by a New Dual-Phase Ceramic Carbonate Membrane Reactor CX(s)...

224

Pore-Level Modeling of Carbon Dioxide Infiltrating the Ocean Floor  

NLE Websites -- All DOE Office Websites (Extended Search)

Infiltrating the Ocean Floor Infiltrating the Ocean Floor Grant S. Bromhal, Duane H. Smith, US DOE, National Energy Technology Laboratory, Morgantown, WV 26507-0880; M. Ferer, Department of Physics, West Virginia University, Morgantown, WV 26506-6315 Ocean sequestration of carbon dioxide is considered to be a potentially important method of reducing greenhouse gas emissions (US DOE, 1999). Oceans are currently the largest atmospheric carbon dioxide sink; and certainly, enough storage capacity exists in the oceans to hold all of the CO 2 that we can emit for many years. Additionally, technologies exist that allow us to pump liquid CO 2 into the oceans at depths between one and two kilometers for extended periods of time and five times that deep for shorter durations. The biggest unknown in the ocean sequestration process, however, is the fate and

225

Second-generation pressurized fluidized bed combustion cold flow model tests of Phase 2 carbonizer  

SciTech Connect

Under US Department of Energy Contract DE-AC21-86MC21023, Foster Wheeler Development Corporation (FWDC) is developing a second-generation pressurized fulidized bed (PFB) combustion system. The second-generation system is an improvement over first-generation pressurized systems because higher gas turbine inlet temperatures, and thus greater system efficiencies can be achieved. In first-generation systems, the gas turbine operates at temperatures lower than those in the PFB combusting bed, with the latter being limited to approximately 1600{degree}F to control alkali release/gas turbine hot corrosion. The second-generation system overcomes this temperature restriction by including a carbonizer and a topping combustor in the system. The carbonizer is a PFB combustion unit that converts coal to a low-Btu fuel gas and char. The char is transferred to a PFB combustor (PFBC), where it is burned. The flue gas from the PFBC and the fuel gas from the carbonizer go to the topping combustor, where the fuel gas is burned and gas turbine inlet temperatures in excess of 2100{degree}F are generated. The PFBC can be operated with or without coal fed along with the char. Steam is generated in the PFBC, and additional coal fed to the PFBC with the char will result in more steam generation. However, excess air must be kept at a level sufficient to support combustion of the fuel gas in the topping combustor.

Shenker, J.

1991-07-01T23:59:59.000Z

226

Determination of the Controls on Permeability and Transport in Shale by Use of Percolation Models  

E-Print Network (OSTI)

A proper understanding of reservoir connectivity is essential to understanding the relationship between the porosity and the permeability within it. Additionally, the construction of an accurate reservoir model cannot be accomplished without this information. While a great deal is known about the connectivity in conventional sandstone systems, little is understood about the connectivity and its resultant properties within shale systems. Percolation theory is a method to describe the global properties of the shale system by understanding the nanometer scale interaction of pore space. In this study we use both analytical and empirical techniques to further understand shale pore scale interactions as well as global phenomena of the shale system. Construction of pore scale connectivity simulations on lattice and in the continuum allow for understanding relationships between pore topology, system porosity and system permeability. Additionally, questions regarding the role of Total Organic Carbon as well as natural fractures in contributing to shale permeability will be discussed. Analytical techniques are used to validate simulation results regarding the onset of percolation and related pore topology. Finally, time of flight simulation is used to further understand pressure transient behavior in the resulting topological models. High aspect ratio pores are shown to be the driver of shale permeability as opposed to the low aspect ratio pore space associated with organic matrix. Additionally, systems below the percolation threshold are likely able to produce because the wellbore will often encounter near infinite clusters. Finally, a characteristic volume growth profile is shown for a multi-porosity system whereby each level of porosity displays a corresponding stair step of volume growth in time.

Chapman, Ian

2012-08-01T23:59:59.000Z

227

Applications of Lagrangian Dispersion Modeling to the Analysis of Changes in the Specific Absorption of Elemental Carbon  

DOE Green Energy (OSTI)

We use a Lagrangian dispersion model driven by a mesoscale model with four-dimensional data assimilation to simulate the dispersion of elemental carbon (EC) over a region encompassing Mexico City and its surroundings, the study domain for the 2006 MAX-MEX experiment, which was a component of the MILAGRO campaign. The results are used to identify periods when biomass burning was likely to have had a significant impact on the concentrations of elemental carbon at two sites, T1 and T2, downwind of the city, and when emissions from the Mexico City Metropolitan Area (MCMA) were likely to have been more important. They are also used to estimate the median ages of EC affecting the specific absorption of light, aABS, at 870 nm as well as to identify periods when the urban plume from the MCMA was likely to have been advected over T1 and T2. Values of aABS at T1, the nearer of the two sites to Mexico City, were smaller at night and increased rapidly after mid-morning, peaking in the mid-afternoon. The behavior is attributed to the coating of aerosols with substances such as sulfate or organic carbon during daylight hours, but such coating appears to be limited or absent at night. Evidence for this is provided by scanning electron microscope images of aerosols collected at three sampling sites. During daylight hours the values of aABS did not increase with aerosol age for median ages in the range of 1-4 hours. There is some evidence for absorption increasing as aerosols were advected from T1 to T2 but the statistical significance of that result is not strong.

Doran, J. C.; Fast, Jerome D.; Barnard, James C.; Laskin, Alexander; Desyaterik, Yury; Gilles, Marry K.; Hopkins, Rebecca J.

2008-03-07T23:59:59.000Z

228

DEVELOPMENT OF A VALIDATED MODEL FOR USE IN MINIMIZING NOx EMISSIONS AND MAXIMIZING CARBON UTILIZATION WHEN COFIRING BIOMASS WITH COAL  

DOE Green Energy (OSTI)

This is the first Quarterly Technical Report for DOE Cooperative Agreement No. DE-FC26-00NT40895. A statement of the project objectives is included in the Introduction of this report. The project goals and detailed plans were presented in two project kickoff meetings; one at NETL in Pittsburgh and one in Birmingham, AL at Southern Research Institute. Progress has been made in developing a modeling approach to synthesize the reaction time and temperature distributions that will be produced by computational fluid dynamic models of the pilot-scale combustion furnace and the char burnout and chemical reaction kinetics that will predict NOx emissions and unburned carbon levels in the furnace exhaust. Preparations are under way for the initial pilot-scale combustion experiments.

Larry G. Felix; P. Vann Bush; Stephen Niksa

2001-01-24T23:59:59.000Z

229

Long-run Implications of a Forest-based Carbon Sequestration Policy on the United States Economy: A Computable General Equilibrium (CGE) Modeling Approach  

E-Print Network (OSTI)

The economic impacts of a government-funded, forest-based sequestration program were analyzed under two different payment schemes. The impacts were obtained by developing a regional, static CGE model built to accommodate a modified IMPLAN SAM for a determined region in the United States for 2008. The IMPLAN SAM was modified to accommodate the more conventional factors of production (labor, capital and land) and to account for land heterogeneity using the Major Land Resource Areas (MLRA). The regional aggregation considered included the Southern, Northeastern, Southwestern and Midwestern regions. The two policy scenarios considered consisted of two CO2-offset payment schemes: 1) the government compensates the generation of CO2-offsets only by the land converted to a carbon graveyard and 2) the government additionally compensates the CO2 offsets generated as a by-product by the existing commercial logging activity. By doing an analysis of the model with different budget magnitudes under the two scenarios, two different CO2-offset supply schedules were obtained with their respective CO2-offset price and quantity sets. For a budget allocation of $6.9 billion, approximately 1 billion metric tons of CO2 offsets (15% of U.S. 2008 total GHG emissions) were produced in the first scenario versus 0.8 billion metric tons (11% of U.S. 2008 GHG net emissions) in the second one. Fifty million acres were diverted out of agriculture and commercial forestry land to the carbon graveyard mainly in the Northern, Western and Central Great Plains in the first scenario. Twenty two million acres were diverted out of agricultural land to the carbon graveyard and commercial logging mainly in the Northern and Western Great Plains; and the Eastern and Western boundaries of the Appalachian Mountains in the second scenario. Both scenarios resulted in higher land and agricultural commodity prices, lower consumption of agricultural commodities by households, lower agricultural exports and higher imports. The payment structure of the second scenario benefited the commercial logging industry, increasing its production and exports, and decreasing its imports. The non-agricultural sectors mostly impacted by the two policy scenarios were the manufacturing, construction and government employment sectors.

Monge, Juan

2012-08-01T23:59:59.000Z

230

Design and Validation of an Offline Oceanic Tracer Transport Model for a Carbon Cycle Study  

Science Conference Proceedings (OSTI)

An offline passive tracer transport model with self-operating diagnostic-mode vertical mixing and horizontal diffusion parameterizations is used with assimilated ocean currents to find the chlorofluorocarbon (CFC-11) cycle in oceans. This model ...

Vinu Valsala; Shamil Maksyutov; Ikeda Motoyoshi

2008-06-01T23:59:59.000Z

231

A Thermodynamic Model for Predicting Mineral Reactivity in Supercritical Carbon Dioxide: I. Phase Behavior of Carbon Dioxide - Water - Chloride Salt Systems Across the H2O-Rich to the CO2-Rich Regions  

Science Conference Proceedings (OSTI)

Phase equilibria in mixtures containing carbon dioxide, water, and chloride salts have been investigated using a combination of solubility measurements and thermodynamic modeling. The solubility of water in the CO2-rich phase of ternary mixtures of CO2, H2O and NaCl or CaCl2 was determined, using near infrared spectroscopy, at 90 atm and 40 to 100 °C. These measurements fill a gap in the experimental database for CO2 water salt systems, for which phase composition data have been available only for the H2O-rich phases. A thermodynamic model for CO2 water salt systems has been constructed on the basis of the previously developed Mixed-Solvent Electrolyte (MSE) framework, which is capable of modeling aqueous solutions over broad ranges of temperature and pressure, is valid to high electrolyte concentrations, treats mixed-phase systems (with both scCO2 and water present) and can predict the thermodynamic properties of dry and partially water-saturated supercritical CO2 over broad ranges of temperature and pressure. Within the MSE framework the standard-state properties are calculated from the Helgeson-Kirkham-Flowers equation of state whereas the excess Gibbs energy includes a long-range electrostatic interaction term expressed by a Pitzer-Debye-Hückel equation, a virial coefficient-type term for interactions between ions and a short-range term for interactions involving neutral molecules. The parameters of the MSE model have been evaluated using literature data for both the H2O-rich and CO2-rich phases in the CO2 - H2O binary and for the H2O-rich phase in the CO2 - H2O - NaCl / KCl / CaCl2 / MgCl2 ternary and multicompontent systems. The model accurately represents the properties of these systems at temperatures from 0°C to 300 °C and pressures up to ~4000 atm. Further, the solubilities of H2O in CO2-rich phases that are predicted by the model are in agreement with the new measurements for the CO2 - H2O - NaCl and CO2 - H2O - CaCl2 systems. Thus, the model can be used to predict the effect of various salts on the water content and water activity in CO2-rich phases on the basis of parameters determined from the properties of aqueous systems. Given the importance of water activity in CO2-rich phases for mineral reactivity, the model can be used as a foundation for predicting mineral transformations across the entire CO2/H2O composition range from aqueous solution to anhydrous scCO2. An example application using the model is presented which involves the transformation of forsterite to nesquehonite as a function of temperature and water content in the CO2-rich phase.

Springer, Ronald D.; Wang, Zheming; Anderko, Andre; Wang, Peiming; Felmy, Andrew R.

2012-09-05T23:59:59.000Z

232

Categorical Exclusion Determinations: Kansas | Department of Energy  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

December 11, 2009 December 11, 2009 CX-002611: Categorical Exclusion Determination Modeling Carbon Dioxide Sequestration in Saline Aquifer and Depleted Oil Reservoir to Evaluate Regional Carbon Dioxide Sequestration Potential of Ozark Plateau Aquifer System, South-Central Kansas CX(s) Applied: B3.1, A9 Date: 12/11/2009 Location(s): Manhattan, Kansas Office(s): Fossil Energy, National Energy Technology Laboratory December 11, 2009 CX-002612: Categorical Exclusion Determination Modeling Carbon Dioxide Sequestration in Saline Aquifer and Depleted Oil Reservoir to Evaluate Regional Carbon Dioxide Sequestration Potential of Ozark Plateau Aquifer System, South-Central Kansas CX(s) Applied: B3.1, A9 Date: 12/11/2009 Location(s): Lawrence, Kansas Office(s): Fossil Energy, National Energy Technology Laboratory

233

Carbon Nanotubes Information at NIST  

Science Conference Proceedings (OSTI)

... John Bonevich. Laser Applications Heat Up for Carbon Nanotubes. Longer is Better for Nanotube Optical Properties. Modeling ...

2010-10-05T23:59:59.000Z

234

The Path of Carbon in Photosynthesis VI.  

E-Print Network (OSTI)

factors which determined the rate at which carbon dioxidefactor in the experiments designed to discover tha complex pro- cess by which carbon dioxide

Calvin, M.

1949-01-01T23:59:59.000Z

235

Carbon nanotube nanoelectrode arrays  

DOE Patents (OSTI)

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

Ren, Zhifeng (Newton, MA); Lin, Yuehe (Richland, WA); Yantasee, Wassana (Richland, WA); Liu, Guodong (Fargo, ND); Lu, Fang (Burlingame, CA); Tu, Yi (Camarillo, CA)

2008-11-18T23:59:59.000Z

236

VISION Model: Description of Model Used to Estimate the Impact of Highway Vehicle Technologies and Fuels on Energy Use and Carbon Emissions to 2050  

NLE Websites -- All DOE Office Websites (Extended Search)

ESD/04-1 ESD/04-1 VISION Model: Description of Model Used to Estimate the Impact of Highway Vehicle Technologies and Fuels on Energy Use and Carbon Emissions to 2050 Center for Transportation Research Argonne National Laboratory Operated by The University of Chicago, under Contract W-31-109-Eng-38, for the United States Department of Energy Argonne National Laboratory, a U.S. Department of Energy Office of Science laboratory, is operated by The University of Chicago under contract W-31-109-Eng-38. DISCLAIMER This report was prepared as an account of work sponsored by an agency of the United States Government. Neither the United States Government nor any agency thereof, nor The University of Chicago, nor any of their employees or officers, makes any warranty, express or implied, or assumes

237

Computer Modeling of Carbon Metabolism Enables Biofuel Engineering (Fact Sheet), The Spectrum of Clean Energy Innovation, NREL (National Renewable Energy Laboratory)  

NLE Websites -- All DOE Office Websites (Extended Search)

Computer Modeling of Computer Modeling of Carbon Metabolism Enables Biofuel Engineering In an effort to reduce the cost of biofuels, the National Renewable Energy Laboratory (NREL) has merged biochemistry with modern computing and mathematics. The result is a model of carbon metabolism that will help researchers understand and engineer the process of photosynthesis for optimal biofuel production. Organisms like green algae, grasses, and trees use photosynthesis to transform light energy and carbon dioxide into chemicals-chemicals that can be turned back into energy when used as biofuels or feedstocks for biofuel production. Researchers at NREL have set out to make photo- synthesis more efficient, so that more energy can be captured as biofuels. To improve the efficiency

238

One-dimensional turbulence model simulations of autoignition of hydrogen/carbon monoxide fuel mixtures in a turbulent jet  

Science Conference Proceedings (OSTI)

The autoignition of hydrogen/carbon monoxide in a turbulent jet with preheated co-flow air is studied using the one-dimensional turbulence (ODT) model. The simulations are performed at atmospheric pressure based on varying the jet Reynolds number and the oxidizer preheat temperature for two compositions corresponding to varying the ratios of H{sub 2} and CO in the fuel stream. Moreover, simulations for homogeneous autoignition are implemented for similar mixture conditions for comparison with the turbulent jet results. The results identify the key effects of differential diffusion and turbulence on the onset and eventual progress of autoignition in the turbulent jets. The differential diffusion of hydrogen fuels results in a reduction of the ignition delay relative to similar conditions of homogeneous autoignition. Turbulence may play an important role in delaying ignition at high-turbulence conditions, a process countered by the differential diffusion of hydrogen relative to carbon monoxide; however, when ignition is established, turbulence enhances the overall rates of combustion of the non-premixed flame downstream of the ignition point. (author)

Gupta, Kamlesh G.; Echekki, Tarek [Department of Mechanical and Aerospace Engineering, North Carolina State University, NC (United States)

2011-02-15T23:59:59.000Z

239

The use of stored carbon reserves in growth of temperate tree roots and leaf buds: Analyses using radiocarbon measurements and modeling  

Science Conference Proceedings (OSTI)

Characterizing the use of carbon (C) reserves in trees is important for understanding regional and global C cycles, stress responses, asynchrony between photosynthetic activity and growth demand, and isotopic exchanges in studies of tree physiology and ecosystem C cycling. Using an inadvertent, whole-ecosystem radiocarbon ({sup 14}C) release in a temperate deciduous oak forest and numerical modeling, we estimated that the mean age of stored C used to grow both leaf buds and new roots is 0.7 years and about 55% of new-root growth annually comes from stored C. Therefore, the calculated mean age of C used to grow new-root tissue is {approx}0.4 years. In short, new roots contain a lot of stored C but it is young in age. Additionally, the type of structure used to model stored C input is important. Model structures that did not include storage, or that assumed stored and new C mixed well (within root or shoot tissues) before being used for root growth, did not fit the data nearly as well as when a distinct storage pool was used. Consistent with these whole-ecosystem labeling results, the mean age of C in new-root tissues determined using 'bomb-{sup 14}C' in three additional forest sites in North America and Europe (one deciduous, two coniferous) was less than 1-2 years. The effect of stored reserves on estimated ages of fine roots is unlikely to be large in most natural abundance isotope studies. However, models of root C dynamics should take stored reserves into account, particularly for pulse-labeling studies and fast-cycling roots (<1 years).

Gaudinski, J.B.; Torn, M.S.; Riley, W.J.; Swanston, C.; Trumbore, S.E.; Joslin, J.D.; Majdi, H.; Dawson, T.E.; Hanson, P.J.

2009-02-01T23:59:59.000Z

240

The Role of Carbon Capture and Storage in a Lower Carbon World  

NLE Websites -- All DOE Office Websites (Extended Search)

role of Carbon Capture and Storage in a role of Carbon Capture and Storage in a Lower Carbon World Past Compliance model Regulations determine 'acceptability' of risks, Our performance judged by regulators view of compliance, Industry focused upon cost and pace of new regulations, Managed as a License to Operate issue, Current Reputation model 'Acceptability' of risk set by our own expectations, Responsible care determined by opinion formers, Our focus is upon investing in our Corporate Reputation, Success recognised by governments, NGOs and suppliers. Future Customer model BP fuels our customers economic and social growth, while allowing them to invest in their own environment through us, Our offer is to help Customers manage their environmental impact, The environment becomes an integral part of individual customer

Note: This page contains sample records for the topic "determination modeling carbon" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


241

Variational Data Assimilation for Determining the Seasonal Net Surface Heat Flux Using a Tropical Pacific Ocean Model  

Science Conference Proceedings (OSTI)

The authors present a study for determining the seasonal net surface heat flux over the tropical Pacific Ocean using an adjoint technique. A simple tropical ocean model with thermodynamics is chosen and the seasonal sea surface temperature (SST) ...

Lisan Yu; James J. O'Brien

1995-10-01T23:59:59.000Z

242

Mitigation of atmospheric carbon emissions through increased energy efficiency versus increased non-carbon energy sources: A trade study using a simplified {open_quotes}market-free{close_quotes} exogenously driven model  

SciTech Connect

A simplified model of global, long-term energy use is described and used to make a `top-level` comparison of two generic approaches for mitigating atmospheric carbon emissions: (a) those based on increased energy efficiency; and (b) those based on increased use of reduced- or non-carbon fuels. As approximate as is the model, first-order estimates of and trade offs between increasing non-carbon generation capacities (e.g., supply-side solutions) versus energy-use efficiency (e.g., demand-side solutions) to stem atmospheric carbon accumulations can be useful in guiding more elaborate models. At the level of this analysis, both the costs of abatement and the costs of damage can be large, with the formation of benefit-to-cost ratios as a means of assessment being limited by uncertainties associated with relating given climatic responses to greenhouse warming to aggregate damage cost, as well as uncertainties associated with procedures used for multi-generation discounting of both abatement and damage costs. In view of uncertainties associated with both supply-side and demand-side approaches, as well as the estimation of greenhouse-warming responses per se, a combination of solutions seems prudent. Key findings are: (a) the relative insensitivity of the benefit-to-cost ratio adopted in this study to supply-side versus demand-side approaches to abating atmospheric carbon-dioxide emissions; (b) the extreme sensitivity of damage costs, abatement costs, and the related benefit-to-cost ratios to the combination of discounting procedure and the (time) concavity of the function used to relate global temperature rise to damage costs; and (c) no matter the discounting procedure and/or functional relationship between average temperature rise and a damage cost, a goal of increased per-capita gross world product at minimum damage suggests action now rather than delay.

Krakowski, R.A.

1997-08-24T23:59:59.000Z

243

Nanostructured Electrodes For Organic Bulk Heterojunction Solar Cells: Model Study Using Carbon Nanotube Dispersed Polythiophene-fullerene Blend Devices  

Science Conference Proceedings (OSTI)

We test the feasibility of using nanostructured electrodes in organic bulk heterojunction solar cells to improve their photovoltaic performance by enhancing their charge collection efficiency and thereby increasing the optimal active blend layer thickness. As a model system, small concentrations of single wall carbon nanotubes are added to blends of poly(3-hexylthiophene): [6,6]-phenyl-C{sub 61}-butyric acid methyl ester in order to create networks of efficient hole conduction pathways in the device active layer without affecting the light absorption. The nanotube addition leads to a 22% increase in the optimal blend layer thickness from 90 nm to 110 nm, enhancing the short circuit current density and photovoltaic device efficiency by as much as {approx}10%. The associated incident-photon-to-current conversion efficiency for the given thickness also increases by {approx}10% uniformly across the device optical absorption spectrum, corroborating the enhanced charge carrier collection by nanostructured electrodes.

Nam, C.Y.; Wu, Q.; Su, D.; Chiu, C.-y; Tremblay, N.J.; Nuckolls, C,; Black, C.T.

2011-09-19T23:59:59.000Z

244

Yucca Mountain Area Saturated Zone Dissolved Organic Carbon Isotopic Data  

SciTech Connect

Groundwater samples in the Yucca Mountain area were collected for chemical and isotopic analyses and measurements of water temperature, pH, specific conductivity, and alkalinity were obtained at the well or spring at the time of sampling. For this project, groundwater samples were analyzed for major-ion chemistry, deuterium, oxygen-18, and carbon isotopes of dissolved inorganic carbon (DIC) and dissolved organic carbon (DOC). The U.S. Geological Survey (USGS) performed all the fieldwork on this project including measurement of water chemistry field parameters and sample collection. The major ions dissolved in the groundwater, deuterium, oxygen-18, and carbon isotopes of dissolved inorganic carbon (DIC) were analyzed by the USGS. All preparation and processing of samples for DOC carbon isotopic analyses and geochemical modeling were performed by the Desert Research Institute (DRI). Analysis of the DOC carbon dioxide gas produced at DRI to obtain carbon-13 and carbon-14 values was conducted at the University of Arizona Accelerator Facility (a NSHE Yucca Mountain project QA qualified contract facility). The major-ion chemistry, deuterium, oxygen-18, and carbon isotopes of DIC were used in geochemical modeling (NETPATH) to determine groundwater sources, flow paths, mixing, and ages. The carbon isotopes of DOC were used to calculate groundwater ages that are independent of DIC model corrected carbon-14 ages. The DIC model corrected carbon-14 calculated ages were used to evaluate groundwater travel times for mixtures of water including water beneath Yucca Mountain. When possible, groundwater travel times were calculated for groundwater flow from beneath Yucca Mountain to down gradient sample sites. DOC carbon-14 groundwater ages were also calculated for groundwaters in the Yucca Mountain area. When possible, groundwater travel times were estimated for groundwater flow from beneath Yucca Mountain to down gradient groundwater sample sites using the DOC calculated groundwater ages. The DIC calculated groundwater ages were compared with DOC calculated groundwater ages and both of these ages were compared to travel times developed in ground-water flow and transport models. If nuclear waste is stored in Yucca Mountain, the saturated zone is the final barrier against the release of radionuclides to the environment. The most recent rendition of the TSPA takes little credit for the presence of the saturated zone and is a testament to the inadequate understanding of this important barrier. If radionuclides reach the saturated zone beneath Yucca Mountain, then there is a travel time before they would leave the Yucca Mountain area and flow down gradient to the Amargosa Valley area. Knowing how long it takes groundwater in the saturated zone to flow from beneath Yucca Mountain to down gradient areas is critical information for potential radionuclide transport. Radionuclide transport in groundwater may be the quickest pathway for radionuclides in the proposed Yucca Mountain repository to reach land surface by way of groundwater pumped in Amargosa Valley. An alternative approach to ground-water flow and transport models to determine the travel time of radionuclides from beneath Yucca Mountain to down gradient areas in the saturated zone is by carbon-14 dating of both inorganic and organic carbon dissolved in the groundwater. A standard method of determining ground-water ages is to measure the carbon-13 and carbon-14 of DIC in the groundwater and then correct the measured carbon-14 along a flow path for geochemical reactions that involve carbon containing phases. These geochemical reactions are constrained by carbon-13 and isotopic fractionations. Without correcting for geochemical reactions, the ground-water ages calculated from only the differences in carbon-14 measured along a flow path (assuming the decrease in carbon-14 is due strictly to radioactive decay) could be tens of thousands of years too old. The computer program NETPATH, developed by the USGS, is the best geochemical program for correcting carbon-14 activities for geochemical r

Thomas, James; Decker, David; Patterson, Gary; Peterman, Zell; Mihevc, Todd; Larsen, Jessica; Hershey, Ronald

2007-06-25T23:59:59.000Z

245

Model for determining modular heat recovery incinerator feasibility on air force installations. Master's thesis  

Science Conference Proceedings (OSTI)

This study constructed a model to determine the feasibility of building municipal solid waste (MSW) fired modular heat recovery incinerators (HRIs) on Air Force installations. The model consisted of three gates. Gate one identified current federal regulatory air emission requirements for various HRI pollutants. It also specified two air pollution control configurations with emission reduction efficiencies capable of achieving these requirements. Gate two presented a life-cycle cost (LCC) economic analysis methodology. Operational and cost data for existing modular HRIs located in the United States facilitated the development of regression equations that estimate capital and annual operating costs for a modular HRI. Actual cost and operational information from a central heating plant at Wright-Patterson AFB, along with cost data from the regression equations, provided the basis for an example LCC analysis involving modular HRIs Results of this hypothetical evaluation showed that the LCC for the modular HRI alternatives were both less than the LCC of replacing the existing boiler. Gate three presented a Likert-scale survey to evaluate the sociopolitical acceptability of the proposed HRI. The survey results indicate the level of effort to process the HRI proposal in accordance with the National Environmental Policy Act. Heat recovery, Incinerators, Waste management, Waste treatment.

Anderson, A.H.; Munnell, P.R.

1992-09-01T23:59:59.000Z

246

Bayesian Analysis of QENS data: From parameter determination to model selection  

E-Print Network (OSTI)

The extraction of any physical information from quasielastic neutron scattering spectra is generally done by fitting a model to the data by means of chi-square minimization procedure. However, as pointed out by the pioneering work of D.S. Sivia et al., also another probabilistic approach based on Bayes theorem can be employed. In a nutshell, the main difference between the classical chi-square minimization and the Bayesian approach is the way of expressing the final results: In the first case, the result is a set of values of parameters with a symmetric error and a figure of merit such as chi-square, whereas in the second case the results are presented as probability distribution functions (PDF) of both, parameters and merit figure. In this contribution, we demonstrate how final PDFs are obtained by exploring all possible combinations of parameters that are compatible with the experimental error. Three advantages of this method will be emphasized: First, correlations between parameters are automatically taken into account, which implies, for example, that parameter errors are correctly calculated, correlations show up in a natural way and ill defined parameters are immediately recognized from their PDF. Second, it is possible to calculate the likelihood of a determined physical model, and therefore to select the one among many that fits the data best with a minimal number of parameters, in a correctly defined probabilistic way.

L. C. Pardo; M. Rovira-Esteva; S. Busch; M. D. Ruiz-Martin; J. Ll. Tamarit; T. Unruh

2009-07-21T23:59:59.000Z

247

Long-Term Climate Commitments Projected with Climate–Carbon Cycle Models  

Science Conference Proceedings (OSTI)

Eight earth system models of intermediate complexity (EMICs) are used to project climate change commitments for the recent Intergovernmental Panel on Climate Change’s (IPCC’s) Fourth Assessment Report (AR4). Simulations are run until the year ...

G.-K. Plattner; R. Knutti; F. Joos; T. F. Stocker; W. von Bloh; V. Brovkin; D. Cameron; E. Driesschaert; S. Dutkiewicz; M. Eby; N. R. Edwards; T. Fichefet; J. C. Hargreaves; C. D. Jones; M. F. Loutre; H. D. Matthews; A. Mouchet; S. A. Müller; S. Nawrath; A. Price; A. Sokolov; K. M. Strassmann; A. J. Weaver

2008-06-01T23:59:59.000Z

248

Detailed Spatial Modeling of Carbon Capture and Storage Infrastructure Deployment in the Southwestern United States  

E-Print Network (OSTI)

, Pipeline and Hazardous Materials Administration. 13. US EPA, eGRID Database. 2006, United States are given by EPA Egrid data USEPA (2006) and costs are calculated using the IECM model (Berkenpas et al

California at Davis, University of

249

Integration of remote sensing and ecosystem modelling techniques to estimate forest net carbon uptake  

Science Conference Proceedings (OSTI)

Estimates of forest gross primary production (GPP) can be obtained using a parametric model (C-Fix) that combines ground and remotely sensed data. A methodology is presented to convert these GPP estimates into values of net ecosystem exchange (NEE). ...

F. Maselli; M. Chiesi; L. Fibbi; M. Moriondo

2008-04-01T23:59:59.000Z

250

OPTIMIZATION OF THE CATHODE LONG-TERM STABILITY IN MOLTEN CARBONATE FUEL CELLS: EXPERIMENTAL STUDY AND MATHEMATICAL MODELING  

DOE Green Energy (OSTI)

This project focused on addressing the two main problems associated with state of art Molten Carbonate Fuel Cells, namely loss of cathode active material and stainless steel current collector deterioration due to corrosion. We followed a dual approach where in the first case we developed novel materials to replace the cathode and current collector currently used in molten carbonate fuel cells. In the second case we improved the performance of conventional cathode and current collectors through surface modification. States of art NiO cathode in MCFC undergo dissolution in the cathode melt thereby limiting the lifetime of the cell. To prevent this we deposited cobalt using an electroless deposition process. We also coated perovskite (La{sub 0.8}Sr{sub 0.2}CoO{sub 3}) in NiO thorough a sol-gel process. The electrochemical oxidation behavior of Co and perovskites coated electrodes is similar to that of the bare NiO cathode. Co and perovskite coatings on the surface decrease the dissolution of Ni into the melt and thereby stabilize the cathode. Both, cobalt and provskites coated nickel oxide, show a higher polarization compared to that of nickel oxide, which could be due to the reduced surface area. Cobalt substituted lithium nickel oxide (LiNi{sub 0.8}Co{sub 0.2}O{sub 2}) and lithium cobalt oxide were also studied. LiNi{sub x}Co{sub 1-x}O{sub 2} was synthesized by solid-state reaction procedure using lithium nitrate, nickel hydroxide and cobalt oxalate precursor. LiNi{sub x}Co{sub 1-x}O{sub 2} showed smaller dissolution of nickel than state of art nickel oxide cathode. The performance was comparable to that of nickel oxide. The corrosion of the current collector in the cathode side was also studied. The corrosion characteristics of both SS304 and SS304 coated with Co-Ni alloy were studied. This study confirms that surface modification of SS304 leads to the formation of complex scales with better barrier properties and better electronic conductivity at 650 C. A three phase homogeneous model was developed to simulate the performance of the molten carbonate fuel cell cathode and the complete fuel cell. The homogeneous model is based on volume averaging of different variables in the three phases over a small volume element. This approach can be used to model porous electrodes as it represents the real system much better than the conventional agglomerate model. Using the homogeneous model the polarization characteristics of the MCFC cathode and fuel cell were studied under different operating conditions. Both the cathode and the full cell model give good fits to the experimental data.

Hector Colonmer; Prabhu Ganesan; Nalini Subramanian; Dr. Bala Haran; Dr. Ralph E. White; Dr. Branko N. Popov

2002-09-01T23:59:59.000Z

251

Thermodynamic Models for Vapor-Liquid Equilibria of Nitrogen+Oxygen+Carbon Dioxide at Low Temperatures  

E-Print Network (OSTI)

For the design and optimization of CO2 recovery from alcoholic fermentation processes by distillation, models for vapor-liquid equilibria (VLE) are needed. Two such thermodynamic models, the Peng-Robinson equation of state (EOS) and a model based on Henry's law constants, are proposed for the ternary mixture N2+O2+CO2. Pure substance parameters of the Peng-Robinson EOS are taken from the literature, whereas the binary parameters of the Van der Waals one-fluid mixing rule are adjusted to experimental binary VLE data. The Peng-Robinson EOS describes both binary and ternary experimental data well, except at high pressures approaching the critical region. A molecular model is validated by simulation using binary and ternary experimental VLE data. On the basis of this model, the Henry's law constants of N2 and O2 in CO2 are predicted by molecular simulation. An easy-to-use thermodynamic model, based on those Henry's law constants, is developed to reliably describe the VLE in the CO2-rich region.

Vrabec, J; Buchhauser, U; Meyer-Pittroff, R; Hasse, H

2009-01-01T23:59:59.000Z

252

Grid-BGC: A Grid-Enabled Terrestrial Carbon Cycle Modeling System, Euro-Par 2005  

E-Print Network (OSTI)

Abstract. Grid-BGC is a Grid-enabled terrestrial biogeochemical cycle simulator collaboratively developed by the National Center for Atmospheric Research (NCAR) and the University of Colorado (CU) with funding from NASA. The primary objective of the project is to utilize Globus Grid technology to integrate inexpensive commodity cluster computational resources at CU with the mass storage system at NCAR while hiding the logistics of data transfer and job submission from the scientists. We describe a typical process for simulating the terrestrial carbon cycle, present our solution architecture and software design, and describe our implementation experiences with Grid technology on our systems. By design the Grid-BGC software framework is extensible in that it can utilize other grid-accessible computational resources and can be readily applied to other climate simulation problems which have similar workflows. Overall, this project demonstrates an end-to-end system which leverages Grid technologies to harness distributed resources across organizational boundaries to achieve a cost-effective solution to a computeintensive problem. 1

Jason Cope; Craig Hartsough; Peter Thornton; Henry M. Tufo; Nathan Wilhelmi; Matthew Woitaszek

2005-01-01T23:59:59.000Z

253

CX-006496: Categorical Exclusion Determination | Department of...  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Exclusion Determination CX-006496: Categorical Exclusion Determination Midwest Regional Carbon Sequestration Partnership Phase 3: Michigan 3-Dimensional Seismic Data Collection...

254

CX-000425: Categorical Exclusion Determination | Department of...  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Determination CX-000425: Categorical Exclusion Determination Geoscience Perspectives in Carbon Sequestration: Educational Training and Research through Classroom, Field, and...

255

EA-1835: Environmental Assessment Determination | Department...  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Assessment Determination EA-1835: Environmental Assessment Determination Midwest Regional Carbon Sequestration Partnership (MRCSP) Phase II Michigan Basin Project in Chester...

256

CX-000424: Categorical Exclusion Determination | Department of...  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Determination CX-000424: Categorical Exclusion Determination Geoscience Perspectives in Carbon Sequestration: Educational Training and Research through Classroom, Field, and...

257

CX-000294: Categorical Exclusion Determination | Department of...  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Exclusion Determination CX-000294: Categorical Exclusion Determination A Novel Biogas Desulphurization Sorbent Technology for Molten Carbonate Fuel Cell- Based Combined...

258

CX-000293: Categorical Exclusion Determination | Department of...  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Exclusion Determination CX-000293: Categorical Exclusion Determination A Novel Biogas Desulphurization Sorbent Technology for Molten Carbonate Fuel Cell - Based Combined...

259

CX-000745: Categorical Exclusion Determination | Department of...  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Exclusion Determination CX-000745: Categorical Exclusion Determination Beneficial Carbon Dioxide Capture in an Integrated Algal Biorefinery for Renewable Generation and...

260

CARBON DIOXIDE CAPTURE FROM FLUE GAS USING DRY REGENERABLE SORBENTS  

SciTech Connect

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

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

2002-04-01T23:59:59.000Z

Note: This page contains sample records for the topic "determination modeling carbon" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


261

Carbon taxes and India  

Science Conference Proceedings (OSTI)

Using the Indian module of the Second Generation Model 9SGM, we explore a reference case and three scenarios in which greenhouse gas emissions were controlled. Two alternative policy instruments (carbon taxes and tradable permits) were analyzed to determine comparative costs of stabilizing emissions at (1) 1990 levels (the 1 X case), (2) two times the 1990 levels (the 2X case), and (3) three times the 1990 levels (the 3X case). The analysis takes into account India`s rapidly growing population and the abundance of coal and biomass relative to other fuels. We also explore the impacts of a global tradable permits market to stabilize global carbon emissions on the Indian economy under the following two emissions allowance allocation methods: (1) {open_quotes}Grandfathered emissions{close_quotes}: emissions allowances are allocated based on 1990 emissions. (2) {open_quotes}Equal per capita emissions{close_quotes}: emissions allowances are allocated based on share of global population. Tradable permits represent a lower cost method to stabilize Indian emissions than carbon taxes, i.e., global action would benefit India more than independent actions.

Fisher-Vanden, K.A.; Pitcher, H.M.; Edmonds, J.A.; Kim, S.H. [Pacific Northwest Lab., Richland, WA (United States); Shukla, P.R. [Indian Institute of Management, Ahmedabad (India)

1994-07-01T23:59:59.000Z

262

Determination of High-Frequency Current Distribution Using EMTP-Based Transmission Line Models with Resulting Radiated Electromagnetic Fields  

SciTech Connect

Application of BPL technologies to existing overhead high-voltage power lines would benefit greatly from improved simulation tools capable of predicting performance - such as the electromagnetic fields radiated from such lines. Existing EMTP-based frequency-dependent line models are attractive since their parameters are derived from physical design dimensions which are easily obtained. However, to calculate the radiated electromagnetic fields, detailed current distributions need to be determined. This paper presents a method of using EMTP line models to determine the current distribution on the lines, as well as a technique for using these current distributions to determine the radiated electromagnetic fields.

Mork, B; Nelson, R; Kirkendall, B; Stenvig, N

2009-11-30T23:59:59.000Z

263

Simple model of bulk and surface excitation effects to inelastic scattering in low-energy electron beam irradiation of multi-walled carbon nanotubes  

SciTech Connect

The effect of bulk and surface excitations to inelastic scattering in low-energy electron beam irradiation of multi-walled carbon nanotubes (MWNTs) is studied using the dielectric formalism. Calculations are based on a semiempirical dielectric response function for MWCNTs determined by means of a many-pole plasmon model with parameters adjusted to available experimental spectroscopic data under theoretical sum-rule constrains. Finite-size effects are considered in the context of electron gas theory via a boundary correction term in the plasmon dispersion relations, thus, allowing a more realistic extrapolation of the electronic excitation spectrum over the whole energy-momentum plane. Energy-loss differential and total inelastic scattering cross sections as a function of electron energy and distance from the surface, valid over the energy range {approx}50-30,000 eV, are calculated with the individual contribution of bulk and surface excitations separated and analyzed for the case of normally incident and escaping electrons. The sensitivity of the results to the various approximations for the spatial dispersion of the electronic excitations is quantified. Surface excitations are shown to have a strong influence upon the shape and intensity of the energy-loss differential cross section in the near surface region whereas the general notion of a spatially invariant inelastic mean free path inside the material is found to be of good approximation.

Kyriakou, Ioanna; Emfietzoglou, Dimitris [Medical Physics Lab, University of Ioannina Medical School, 451 10 Ioannina (Greece); Garcia-Molina, Rafael [Departamento de Fisica - CIOyN, Universidad de Murcia, E-30100 Murcia (Spain); Abril, Isabel [Departament de Fisica Aplicada, Universitat d'Alacant, Apartat 99, E-03080 Alacant (Spain); Kostarelos, Kostas [Nanomedicine Lab, Centre for Drug Delivery Research, The School of Pharmacy, University of London, London WC1N 1AX (United Kingdom)

2011-09-01T23:59:59.000Z

264

Transient response of the Hadley Centre coupled ocean-atmosphere model to increasing carbon dioxide. Part 3: Analysis of global-mean response using simple models  

Science Conference Proceedings (OSTI)

The roles of surface, atmospheric, and oceanic feedbacks in controlling the global-mean transient response of a coupled ocean-atmosphere general circulation model (AOGCM) to increasing carbon dioxide are investigated. The analysis employs a four-box energy balance model (EBM) and an oceanic box-diffusion model (BDM) both tuned to the simulated general circulation model response. The land-sea contrast in the surface warming is explained almost entirely by the shortwave radiative feedbacks associated with changes in cloud and surface albedo. The oceanic thermal inertia delays the response; however, the initial delay is enhanced by increases in Anarctic sea-ice cover, which substantially reduce the effective climate sensitivity of the model in the first half of the 75-year experiment. When driven by the observed anthropogenic greenhouse forcing from the pre-industrial period to present day, the energy balance model overestimates the warming observed over land. However, inclusion of the direct forcing due to anthropogenic tropospheric sulphate aerosol eliminates the land/sea contrast in the response at 1990, leaving the simulated warming over land slightly below the observed value, although the rapid warming observed during the 1980s is well reproduced. The vertical penetration of the oceanic response is small below 1000 m. Within the top 1000 m the effective diffusivities are substantially enhanced by reduced convection and thermohaline overturning, driven by increased precipitation minus evaporation at high latitudes. These changes in ocean heat transport become significant after year 30, whereupon the effective oceanic heat capacity increases substantially, although this increase is partially offset by the effect of changes in the sea-ice margin.

Murphy, J.M. [Meteorological Office, Bracknell, Berkshire (United Kingdom)

1995-03-01T23:59:59.000Z

265

Transient Response of the Hadley Centre Coupled Ocean-Atmosphere Model to Increasing Carbon Dioxide. Part II: Spatial and Temporal Structure of Response  

Science Conference Proceedings (OSTI)

A high-resolution (2.75° lat × ° 3.75° long) coupled ocean-atmosphere model has been used to simulate the transient response of climate to a gradual increase in atmospheric carbon dioxide concentrations. Although the radiative forcing increases ...

J. M. Murphy; J. F. B. Mitchell

1995-01-01T23:59:59.000Z

266

The Effect of Terrestrial Photosynthesis Down Regulation on the Twentieth-Century Carbon Budget Simulated with the CCCma Earth System Model  

Science Conference Proceedings (OSTI)

The simulation of atmospheric–land–ocean CO2 exchange for the 1850–2000 period offers the possibility of testing and calibrating the carbon budget in earth system models by comparing the simulated changes in atmospheric CO2 concentration and in ...

V. K. Arora; G. J. Boer; J. R. Christian; C. L. Curry; K. L. Denman; K. Zahariev; G. M. Flato; J. F. Scinocca; W. J. Merryfield; W. G. Lee

2009-11-01T23:59:59.000Z

267

Optimal endogenous carbon taxes for electric power supply chains with power plants  

Science Conference Proceedings (OSTI)

In this paper, we develop a modeling and computational framework that allows for the determination of optimal carbon taxes applied to electric power plants in the context of electric power supply chain (generation/distribution/consumption) networks. ... Keywords: Carbon taxes, Electric power, Environmental policies, Network equilibria, Renewable energy, Supply chains, Variational inequalities

Anna Nagurney; Zugang Liu; Trisha Woolley

2006-11-01T23:59:59.000Z

268

http://www.ogj.com/articles/print/volume-111/issue-9/drilling-production/barnett-study-determines-full-field-reserves.html BARNETT SHALE MODEL-2 (Conclusion): Barnett study  

E-Print Network (OSTI)

-production/barnett-study-determines-full-field-reserves.html BARNETT SHALE MODEL-2 (Conclusion): Barnett study determines full-field reserves, production forecast John shale integrates engineering, geology, and economics into a numerical model that allows f or scenario

Patzek, Tadeusz W.

269

Carbon Sequestration  

NLE Websites -- All DOE Office Websites (Extended Search)

andrea Mcnemar andrea Mcnemar National Energy Technology Laboratory 3610 Collins Ferry Road P.O. Box 880 Morgantown, WV 26507-0880 304-285-2024 andrea.mcnemar@netl.doe.gov Gregory J. Elbring Principal Investigator Sandia National Laboratory P.O. Box 5800 Albuquerque, NM 87185 505-844-4904 gjelbri@sandia.gov GeoloGic SequeStration of carbon DioxiDe in a DepleteD oil reServoir: a comprehenSive moDelinG anD Site monitorinG project Background The use of carbon dioxide (CO 2 ) to enhance oil recovery (EOR) is a familiar and frequently used technique in the United States. The oil and gas industry has significant experience with well drilling and injecting CO 2 into oil-bearing formations to enhance production. While using similar techniques as in oil production, this sequestration field

270

Carbon management in assembly manufacturing logistics  

Science Conference Proceedings (OSTI)

In this paper, we present the IBM Carbon Analyzer Tool, a software solution that models and quantifies carbon emissions and explores ways to reduce emissions through advanced analytics. The tool is designed to manage carbon emissions associated with ...

K. Sourirajan; P. Centonze; M. E. Helander; K. Katircioglu; M. Ben-Hamida; C. Boucher

2009-05-01T23:59:59.000Z

271

A Classic Model in a Low Fertility Context: The Proximate Determinants of Fertility in South Korea and the United States  

E-Print Network (OSTI)

John Bongaarts' proximate determinants model of fertility has accounted for over 90 percent of variation in the total fertility rate (TFR) of primarily developing nations and historical populations. Recently, dramatically low fertility rates across the globe have raised questions regarding whether this model could be applied to exclusively below-replacement nations. This study follows Knodel, Chamratrithirong, and Debavalya's 1987 analysis of fertility decline in Thailand by conducting in-depth case studies of the proximate determinants in two low fertility countries over time: South Korea, where fertility is well below the level of replacement, and the United States, where fertility has hovered around replacement level for many years. Then, the fertility-inhibiting effect of the proximate determinants is assessed by comparing the quantitative index representing each determinant measured in the 1960s/1970s with its measurement in the 2000s. For both years, I consider the fertility level that would prevail in the determinant's presence as well as the level that would exist in its absence. Finally, I use each of the indices to calculate the TFR and assess how the strength of the model varies over time in the two countries. Ultimately, results indicate that the proximate determinants model does not offer a clean picture of the fertility level in either South Korea or the United States; when trends uncovered by the case studies are compared to the results of the quantitative analysis, a number of inconsistencies are revealed. This suggests that certain components in the model may need to be respecified for more effective application in low-fertility contexts. However, that is not to say that it offers no insight into fertility at all or that it is no longer a useful tool. On the contrary, it is shown that the proximate determinants model holds a lot of potential for analysis in low-fertility nations. The implications of these results, as well as the need for improvements in international data collection efforts, are also discussed.

Guarneri, Christine E.

2010-05-01T23:59:59.000Z

272

Carbonic Acid Retreatment of Biomass  

DOE Green Energy (OSTI)

This project sought to address six objectives, outlined below. The objectives were met through the completion of ten tasks. (1) Solidify the theoretical understanding of the binary CO{sub 2}/H{sub 2}O system at reaction temperatures and pressures. The thermodynamics of pH prediction have been improved to include a more rigorous treatment of non-ideal gas phases. However it was found that experimental attempts to confirm theoretical pH predictions were still off by a factor of about 1.8 pH units. Arrhenius experiments were carried out and the activation energy for carbonic acid appears to be substantially similar to sulfuric acid. Titration experiments have not yet confirmed or quantified the buffering or acid suppression effects of carbonic acid on biomass. (2) Modify the carbonic acid pretreatment severity function to include the effect of endogenous acid formation and carbonate buffering, if necessary. It was found that the existing severity functions serve adequately to account for endogenous acid production and carbonate effects. (3) Quantify the production of soluble carbohydrates at different reaction conditions and severity. Results show that carbonic acid has little effect on increasing soluble carbohydrate concentrations for pretreated aspen wood, compared to pretreatment with water alone. This appears to be connected to the release of endogenous acids by the substrate. A less acidic substrate such as corn stover would derive benefit from the use of carbonic acid. (4) Quantify the production of microbial inhibitors at selected reaction conditions and severity. It was found that the release of inhibitors was correlated to reaction severity and that carbonic acid did not appear to increase or decrease inhibition compared to pretreatment with water alone. (5) Assess the reactivity to enzymatic hydrolysis of material pretreated at selected reaction conditions and severity. Enzymatic hydrolysis rates increased with severity, but no advantage was detected for the use of carbonic acid compared to water alone. (6) Determine optimal conditions for carbonic acid pretreatment of aspen wood. Optimal severities appeared to be in the mid range tested. ASPEN-Plus modeling and economic analysis of the process indicate that the process could be cost competitive with sulfuric acid if the concentration of solids in the pretreatment is maintained very high ({approx}50%). Lower solids concentrations result in larger reactors that become expensive to construct for high pressure applications.

Baylor university

2003-06-01T23:59:59.000Z

273

Carbonic Acid Pretreatment of Biomass  

SciTech Connect

This project sought to address six objectives, outlined below. The objectives were met through the completion of ten tasks. 1) Solidify the theoretical understanding of the binary CO2/H2O system at reaction temperatures and pressures. The thermodynamics of pH prediction have been improved to include a more rigorous treatment of non-ideal gas phases. However it was found that experimental attempts to confirm theoretical pH predictions were still off by a factor of about 1.8 pH units. Arrhenius experiments were carried out and the activation energy for carbonic acid appears to be substantially similar to sulfuric acid. Titration experiments have not yet confirmed or quantified the buffering or acid suppression effects of carbonic acid on biomass. 2) Modify the carbonic acid pretreatment severity function to include the effect of endogenous acid formation and carbonate buffering, if necessary. It was found that the existing severity functions serve adequately to account for endogenous acid production and carbonate effects. 3) Quantify the production of soluble carbohydrates at different reaction conditions and severity. Results show that carbonic acid has little effect on increasing soluble carbohydrate concentrations for pretreated aspen wood, compared to pretreatment with water alone. This appears to be connected to the release of endogenous acids by the substrate. A less acidic substrate such as corn stover would derive benefit from the use of carbonic acid. 4) Quantify the production of microbial inhibitors at selected reaction conditions and severity. It was found that the release of inhibitors was correlated to reaction severity and that carbonic acid did not appear to increase or decrease inhibition compared to pretreatment with water alone. 5) Assess the reactivity to enzymatic hydrolysis of material pretreated at selected reaction conditions and severity. Enzymatic hydrolysis rates increased with severity, but no advantage was detected for the use of carbonic acid compared to water alone. 6) Determine optimal conditions for carbonic acid pretreatment of aspen wood. Optimal severities appeared to be in the mid range tested. ASPEN-Plus modeling and economic analysis of the process indicate that the process could be cost competitive with sulfuric acid if the concentration of solids in the pretreatment is maintained very high (~50%). Lower solids concentrations result in larger reactors that become expensive to construct for high pressure applications.

G. Peter van Walsum; Kemantha Jayawardhana; Damon Yourchisin; Robert McWilliams; Vanessa Castleberry

2003-05-31T23:59:59.000Z

274

Categorical Exclusion Determination Form  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

of n y of n y Categorical Exclusion Determination Form Proposed Action Title: (0471-1607) University of Florida - Solar Thermochemical Fuel Production via a Novel Low Pressure, Magnetically Stabilized, Non-Volatile Iron Oxide Looping Process Program or Field Office: Advanced Research Projects Agency - Energy LocationCs) CCity/County/State): Gainesville, FL Proposed Action Description: University of Florida proposes to develop a novel solar thermochemical reactor with inputs of water, recycled carbon dioxide (C02), and concentrated solar energy to cost-effectively produce Syngas, a renewable, carbon-neutral fuel. Project activities will include: (1) modeling, design, and fabrication of a high efficiency 1 OkW reactor prototype; (2) test analysis of bench-scale

275

Expanding the potential for saline formations : modeling carbon dioxide storage, water extraction and treatment for power plant cooling.  

Science Conference Proceedings (OSTI)

The National Water, Energy and Carbon Sequestration simulation model (WECSsim) is being developed to address the question, 'Where in the current and future U.S. fossil fuel based electricity generation fleet are there opportunities to couple CO{sub 2} storage and extracted water use, and what are the economic and water demand-related impacts of these systems compared to traditional power systems?' The WECSsim collaborative team initially applied this framework to a test case region in the San Juan Basin, New Mexico. Recently, the model has been expanded to incorporate the lower 48 states of the U.S. Significant effort has been spent characterizing locations throughout the U.S. where CO{sub 2} might be stored in saline formations including substantial data collection and analysis efforts to supplement the incomplete brine data offered in the NatCarb database. WECSsim calculates costs associated with CO{sub 2} capture and storage (CCS) for the power plant to saline formation combinations including parasitic energy costs of CO{sub 2} capture, CO{sub 2} pipelines, water treatment options, and the net benefit of water treatment for power plant cooling. Currently, the model can identify the least-cost deep saline formation CO{sub 2} storage option for any current or proposed coal or natural gas-fired power plant in the lower 48 states. Initial results suggest that additional, cumulative water withdrawals resulting from national scale CCS may range from 676 million gallons per day (MGD) to 30,155 MGD depending on the makeup power and cooling technologies being utilized. These demands represent 0.20% to 8.7% of the U.S. total fresh water withdrawals in the year 2000, respectively. These regional and ultimately nation-wide, bottom-up scenarios coupling power plants and saline formations throughout the U.S. can be used to support state or national energy development plans and strategies.

Not Available

2011-04-01T23:59:59.000Z

276

A Complete Transport Validated Model on a Zeolite Membrane for Carbon Dioxide Permeance and Capture  

E-Print Network (OSTI)

The CO2 emissions from major industries cause serious global environment problems and their mitigation is urgently needed. The use of zeolite membranes is a very efficient way in order to capture CO2 from some flue gases. The dominant transport mechanism at low temperature andor high pressure is the diffusion through the membrane. This procedure can be divided in three steps: Adsorption of the molecules of the species in the surface of the membrane, then a driving force gives a path where the species follow inside the membrane and finally the species desorbed from the surface of the membrane. The current work is aimed at developing a simulation model for the CO2 transport through a zeolite membrane and estimate the diffusion phenomenon through a very thin membrane of 150 nm in a Wicke-Kallenbach cell. The cell is cylindrical in shape with diameter of 19 mm and consists of a retentate gas chamber, a permeate gas chamber which are separated by a cylindrical zeolite membrane. This apparatus have been modeled wit...

Gkanas, Evangelos I; Stubos, Athanasios K; Makridis, Sofoklis S

2013-01-01T23:59:59.000Z

277

CX-008491: Categorical Exclusion Determination | Department of...  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Categorical Exclusion Determination Carbon Dioxide Capture from Integrated Gasification Combined Cycle Gas Streams Using the Ammonium Carbonate-Ammonium Bicarbonate Process CX(s)...

278

CX-008490: Categorical Exclusion Determination | Department of...  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Categorical Exclusion Determination Carbon Dioxide Capture from Integrated Gasification Combined Cycle Gas Streams Using the Ammonium Carbonate-Ammonium Bicarbonate Process CX(s)...

279

CX-000422: Categorical Exclusion Determination | Department of...  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Categorical Exclusion Determination Carbon Dioxide Capture From Integrated Gasification Combined Cycle (IGCC) Gas Streams Using the Ammonium Carbonate-Ammonium Bicarbonate...

280

CX-008492: Categorical Exclusion Determination | Department of...  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Categorical Exclusion Determination Carbon Dioxide Capture from Integrated Gasification Combined Cycle Gas Streams Using the Ammonium Carbonate-Ammonium Bicarbonate Process CX(s)...

Note: This page contains sample records for the topic "determination modeling carbon" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


281

CX-009748: Categorical Exclusion Determination | Department of...  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

CX-009748: Categorical Exclusion Determination Southwest Regional Partnership on Carbon Sequestration: Phase III Commercial-Scale Geologic Carbon Capture, Utilization and...

282

CX-000379: Categorical Exclusion Determination | Department of...  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Categorical Exclusion Determination Sweeney Integrated Gasification Combined CycleCarbon Capture and Sequestration Project - Carbon Dioxide Pipeline and Storage CX(s)...

283

CX-009751: Categorical Exclusion Determination | Department of...  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

CX-009751: Categorical Exclusion Determination Southwest Regional Partnership on Carbon Sequestration: Phase III Commercial-Scale Geologic Carbon Capture, Utilization and...

284

CX-009749: Categorical Exclusion Determination | Department of...  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

CX-009749: Categorical Exclusion Determination Southwest Regional Partnership on Carbon Sequestration: Phase III Commercial-Scale Geologic Carbon Capture, Utilization and...

285

CX-009750: Categorical Exclusion Determination | Department of...  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

CX-009750: Categorical Exclusion Determination Southwest Regional Partnership on Carbon Sequestration: Phase III Commercial-Scale Geologic Carbon Capture, Utilization and...

286

Categorical Exclusion Determinations: National Energy Technology...  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Technology Laboratory December 7, 2009 CX-000459: Categorical Exclusion Determination Molecular Simulation of Dissolved Inorganic Carbons for Underground Brine Carbon Dioxide...

287

Categorical Exclusion Determinations: American Recovery and Reinvestme...  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Exclusion Determination Thermal Integration of Carbon Dioxide Compression Processes with Coal-Fired Power Plants Equipped with Carbon Capture CX(s) Applied: A9 Date: 12072009...

288

Categorical Exclusion Determinations: National Energy Technology...  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

of 222 Radon, 220 Radon, and Carbon Dioxide Emissions in Natural Carbon Dioxide Fields in Wyoming: Monitoring, Verification, and Analysis Techniques for Determining Gas...

289

CX-009848: Categorical Exclusion Determination | Department of...  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

CX-009848: Categorical Exclusion Determination Development of Novel Carbon Sorbents for Carbon Dioxide Capture CX(s) Applied: B3.6 Date: 01302013 Location(s): Alabama...

290

Primary productivity control of simulated carbon cycle-climate feedbacks. Geophys  

E-Print Network (OSTI)

[1] Positive feedbacks between the terrestrial carbon cycle and climate represent an outstanding area of uncertainty in simulations of future climate change. Coupled climatecarbon cycle models have simulated widely divergent feedback magnitudes, and attempts to explain model differences have had only limited success. In this study, we demonstrate that the response of vegetation primary productivity to climate changes is a critical controlling factor in determining the strength of simulated carbon cycle-climate feedbacks. This conclusion sheds new light on coupled climate-carbon cycle model results, and highlights the need for improved model representation of photosynthesis processes so as to better constrain future projections of climate change. Citation: Matthews, H. D.,

H. Damon Matthews; Michael Eby; Andrew J. Weaver; Barbara J. Hawkins; M. Eby; A. J. Weaver; B. J. Hawkins

2005-01-01T23:59:59.000Z

291

NETL: Carbon Storage - Infrastructure  

NLE Websites -- All DOE Office Websites (Extended Search)

Infrastructure Infrastructure Carbon Storage Infrastructure The Infrastructure Element of DOE's Carbon Storage Program is focused on research and development (R&D) initiatives to advance geologic CO2 storage toward commercialization. DOE determined early in the program's development that addressing CO2 mitigation on a regional level is the most effective way to address differences in geology, climate, population density, infrastructure, and socioeconomic development. This element includes the following efforts designed to support the development of regional infrastructure for carbon capture and storage (CCS). Click on Image to Navigate Infrastructure Content on this page requires a newer version of Adobe Flash Player. Get Adobe Flash player Regional Carbon Sequestration Partnerships (RCSP) - This

292

CARBON-CARBON COMPOSITE ALLCOMP Carbon-Carbon Composite  

E-Print Network (OSTI)

strength 4340 steel, carbon-carbon composite, and Carbon-Silicon Carbide composite were tested to examine-C composite containing continuous PAN T300 fibers · SWB: Chopped Fiber Composite containing SWB fibers Crush

Rollins, Andrew M.

293

Modeling of the performance of carbon nanotube bundle, cu/low-k and optical on-chip global interconnects  

Science Conference Proceedings (OSTI)

In this work, we have quantified and compared the performance of carbon nanotube (CNT) and optical interconnects with the existing technology of Cu/low-K interconnects for future high-performance ICs. We present these comparisons not only in terms of ... Keywords: Cu, Global interconnects, bandwidth density, carbon nanotube, latency, optics, power

Hoyeol Cho; Kyung-Hoae Koo; Pawan Kapur; Krishna C. Saraswat

2007-03-01T23:59:59.000Z

294

Use of scale models to determine thermo-hydromechanics of hot-dry-rock reservoirs. Final report  

DOE Green Energy (OSTI)

The study reported here had as its main objective a determination of the feasibility of physical scale models as a way to confirm mathematical models and to explore fundamental behavior of hydraulically-fractured hot dry rock reservoirs. Included in the study are: similitude analyses, based on full-scale data, simplified mathematical models, and physical reasoning, formulation of scaling laws from the similitude analyses, preliminary determination of the processes and phenomena that can be reliably studied in scale model tests, and recommended test program to implement the results of the study. Many of the major studies conducted in hot dry rock reservoir engineering were reviewed and evaluated in the course of meeting the objectives of this study.

Dodge, F.T.

1982-03-01T23:59:59.000Z

295

Modeling the Behavior of Formate, Acetate, and Carbon Dioxide in Water/Steam Cycles  

SciTech Connect

Organic substances persist in high-temperature aqueous environments for varying periods of tiem depending on temperature, pH, contact with solid surfaces, and other factors. Since carboxylic acids and CO{sub 2} affect the pH and can potentially play specific roles in the promotion of inhibition of turbine corrosion, it is important to be able to predict the amounts of these substances that are transferred to steam and the composition of the early condensate as a function of condesnation ratio for various boiler chemistries. Such predictions can only be made using a speciated model including all the solutes. Example calculations for AVT and OT chemistry show complex relationships between early condensate enrichment ratios and boiler pressure, boiler water composition, and condensation ratio. Even small amounts of sodium and chloride below 0.1 {mu}g {center_dot} kg{sup -1} in the steam are relevant to early condensate pH and carboxylic acid concentration. The calculations show that the enrichment of the early condensate relative to steam is typically 10 times greater for formate than for acetate.

Gruszkiewicz, Miroslaw {Mirek} S [ORNL; Palmer, Donald [ORNL

2004-01-01T23:59:59.000Z

296

Determining educational adequacy in Michigan| An adequacy study utilizing the exemplary schools costing-out model.  

E-Print Network (OSTI)

?? The Michigan legislature determines the annual pupil foundation allowance based on available revenues and not on research. As a result of the school reform… (more)

Ochalek, Marianne K.

2009-01-01T23:59:59.000Z

297

Determination of Forecast Errors Arising from Different Components of Model Physics and Dynamics  

Science Conference Proceedings (OSTI)

This paper addresses a procedure to extract error estimates for the physical and dynamical components of a forecast model. This is a two-step process in which contributions to the forecast tendencies from individual terms of the model equations ...

T. N. Krishnamurti; J. Sanjay; A. K. Mitra; T. S. V. Vijaya Kumar

2004-11-01T23:59:59.000Z

298

Reconciling carbon-cycle concepts, terminology, and methods  

E-Print Network (OSTI)

factors that determine whether particularly a or net source is sink of ecosystem atmospheric carbon dioxide (

2006-01-01T23:59:59.000Z

299

Synthesis of Remote Sensing and Field Observations to Model and Understand Disturbance and Climate Effects on the Carbon Balance of Oregon & Northern California  

SciTech Connect

The goal is to quantify and explain the carbon (C) budget for Oregon and N. California. The research compares "bottom -up" and "top-down" methods, and develops prototype analytical systems for regional analysis of the carbon balance that are potentially applicable to other continental regions, and that can be used to explore climate, disturbance and land-use effects on the carbon cycle. Objectives are: 1) Improve, test and apply a bottom up approach that synthesizes a spatially nested hierarchy of observations (multispectral remote sensing, inventories, flux and extensive sites), and the Biome-BGC model to quantify the C balance across the region; 2) Improve, test and apply a top down approach for regional and global C flux modeling that uses a model-data fusion scheme (MODIS products, AmeriFlux, atmospheric CO2 concentration network), and a boundary layer model to estimate net ecosystem production (NEP) across the region and partition it among GPP, R(a) and R(h). 3) Provide critical understanding of the controls on regional C balance (how NEP and carbon stocks are influenced by disturbance from fire and management, land use, and interannual climate variation). The key science questions are, "What are the magnitudes and distributions of C sources and sinks on seasonal to decadal time scales, and what processes are controlling their dynamics? What are regional spatial and temporal variations of C sources and sinks? What are the errors and uncertainties in the data products and results (i.e., in situ observations, remote sensing, models)?

Beverly Law; David Turner; Warren Cohen; Mathias Goeckede

2008-05-22T23:59:59.000Z

300

Models for evaluation of energy technology and policy options to maximize low carbon source penetration in the United States energy supply.  

SciTech Connect

An initial version of a Systems Dynamics (SD) modeling framework was developed for the analysis of a broad range of energy technology and policy questions. The specific question selected to demonstrate this process was 'what would be the carbon and import implications of expanding nuclear electric capacity to provide power for plug in hybrid vehicles?' Fifteen SNL SD energy models were reviewed and the US Energy and Greenhouse gas model (USEGM) and the Global Nuclear Futures model (GEFM) were identified as the basis for an initial modeling framework. A basic U.S. Transportation model was created to model U.S. fleet changes. The results of the rapid adoption scenario result in almost 40% of light duty vehicles being PHEV by 2040 which requires about 37 GWy/y of additional electricity demand, equivalent to about 25 new 1.4 GWe nuclear plants. The adoption rate of PHEVs would likely be the controlling factor in achieving the associated reduction in carbon emissions and imports.

Pickard, Paul S.; Kataoka, Dawn; Reno, Marissa Devan; Malczynski, Leonard A.; Peplinski, William J.; Roach, Jesse D.; Brainard, James Robert; West, Todd H.; Schoenwald, David Alan

2009-12-01T23:59:59.000Z

Note: This page contains sample records for the topic "determination modeling carbon" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


301

DETERMINATION OF ELECTROCHEMICAL PERFORMANCE, AND THERMO-MECHANICALCHEMICAL STABILITY OF SOFCS FROM DEFECT MODELING  

DOE Green Energy (OSTI)

The objectives of this project were to: provide fundamental relationships between SOFC performance and operating conditions and transient (time dependent) transport properties; extend models to thermo-mechanical stability, thermo-chemical stability, and multilayer structures; incorporate microstructural effects such as grain boundaries and grain-size distribution; experimentally verify models and devise strategies to obtain relevant material constants; and assemble software package for integration into SECA failure analysis models.

Wachsman, E.D.; Duncan, K.L.; Ebrahimi, F.

2005-01-27T23:59:59.000Z

302

A MODEL FOR DETERMINING DIPOLE, QUADRUPOLE, AND COMBINED FUNCTION MAGNET COSTS.  

SciTech Connect

One of the most important considerations in designing large accelerators is cost. This paper describes a model for estimating accelerator magnet costs, including their dependences on length, radius, and field. The reasoning behind the cost model is explained, and the parameters of the model are chosen so as to correctly give the costs of a few selected magnets. A comparison is made with earlier formulae. Estimates are also given for other costs linearly dependent on length, and for 200 MHz superconducting RF.

PALMER, R.B.; BERG,S.J.

2004-09-14T23:59:59.000Z

303

Determining Wind Turbine Gearbox Model Complexity Using Measurement Validation and Cost Comparison: Preprint  

DOE Green Energy (OSTI)

The Gearbox Reliability Collaborative (GRC) has conducted extensive field and dynamometer test campaigns on two heavily instrumented wind turbine gearboxes. In this paper, data from the planetary stage is used to evaluate the accuracy and computation time of numerical models of the gearbox. First, planet-bearing load and motion data is analyzed to characterize planetary stage behavior in different environments and to derive requirements for gearbox models and life calculations. Second, a set of models are constructed that represent different levels of fidelity. Simulations of the test conditions are compared to the test data and the computational cost of the models are compared. The test data suggests that the planet-bearing life calculations should be made separately for each bearing on a row due to unequal load distribution. It also shows that tilting of the gear axes is related to planet load share. The modeling study concluded that fully flexible models were needed to predict planet-bearing loading in some cases, although less complex models were able to achieve good correlation in the field-loading case. Significant differences in planet load share were found in simulation and were dependent on the scope of the model and the bearing stiffness model used.

LaCava, W.; Xing, Y.; Guo, Y.; Moan, T.

2012-04-01T23:59:59.000Z

304

CARBON TETRACHLORIDE  

E-Print Network (OSTI)

This fact sheet answers the most frequently asked health questions (FAQs) about carbon tetrachloride.

unknown authors

2005-01-01T23:59:59.000Z

305

Method of and apparatus for determining the similarity of a biological analyte from a model constructed from known biological fluids  

DOE Patents (OSTI)

The characteristics of a biological fluid sample having an analyte are determined from a model constructed from plural known biological fluid samples. The model is a function of the concentration of materials in the known fluid samples as a function of absorption of wideband infrared energy. The wideband infrared energy is coupled to the analyte containing sample so there is differential absorption of the infrared energy as a function of the wavelength of the wideband infrared energy incident on the analyte containing sample. The differential absorption causes intensity variations of the infrared energy incident on the analyte containing sample as a function of sample wavelength of the energy, and concentration of the unknown analyte is determined from the thus-derived intensity variations of the infrared energy as a function of wavelength from the model absorption versus wavelength function.

Robinson, Mark R. (Albuquerque, NM); Ward, Kenneth J. (Albuquerque, NM); Eaton, Robert P. (Albuquerque, NM); Haaland, David M. (Albuquerque, NM)

1990-01-01T23:59:59.000Z

306

Estimation of methane and carbon dioxide surface fluxes using a 3-D global atmospheric chemical transport model  

E-Print Network (OSTI)

Methane (CH?) and carbon dioxide (CO?) are the two most radiatively important greenhouse gases attributable to human activity. Large uncertainties in their source and sink magnitudes currently exist. We estimate global ...

Chen, Yu-Han, 1973-

2004-01-01T23:59:59.000Z

307

Ozone effects on net primary production and carbon sequestration in the conterminous United States using a biogeochemistry model  

E-Print Network (OSTI)

The effects of air pollution on vegetation may provide an important control on the carbon cycle that has not yet been widely considered. Prolonged exposure to high levels of ozone, in particular, has been observed to inhibit ...

Felzer, Benjamin Seth.; Kicklighter, David W.; Melillo, Jerry M.; Wang, Chien.; Zhuang, Qianlai.; Prinn, Ronald G.

308

Field Demonstration of Horizontal Infill Drilling Using Cost-effective Integrated Reservoir Modeling--Mississippian Carbonates, Central Kansas  

Science Conference Proceedings (OSTI)

Mississippian carbonate reservoirs have produced in excess of 1 billion barrels of oil in Kansas accounting for over 16% of the state's production. With declining production from other age reservoirs, the contribution of Mississippian reservoirs to Kansas's oil production has risen to 43% as of 2004. However, solution-enhanced features such as vertical shale intervals extending from the karst erosional surface at the top introduce complexities/compartmentalizations in Mississippian carbonate reservoirs. Coupled with this, strong water drives charge many of these reservoirs resulting in limited drainage from vertical wells due to high water cuts after an initial period of low water production. Moreover, most of these fields are operated by small independent operators without access to the knowledge bank of modern research in field characterization and exploitation/development practices. Thus, despite increasing importance of Mississippian fields to Kansas production, these fields are beset with low recovery factors and high abandonment rates leaving significant resources in the ground. Worldwide, horizontal infill wells have been successful in draining compartmentalized reservoirs with limited pressure depletion. The intent of this project was to demonstrate the application of horizontal wells to successfully exploit the remaining potential in mature Mississippian fields of the mid-continent. However, it is of critical importance that for horizontal wells to be economically successful, they must be selectively targeted. This project demonstrated the application of initial and secondary screening methods, based on publicly available data, to quickly shortlist fields in a target area for detailed studies to evaluate their potential to infill horizontal well applications. Advanced decline curve analyses were used to estimate missing well-level production data and to verify if the well produced under unchanging bottom-hole conditions--two commonly occurring data constraints afflicting mature Mississippian fields. A publicly accessible databank of representative petrophysical properties and relationships was developed to overcome the paucity of such data that is critical to modeling the storage and flow in these reservoirs. Studies in 3 Mississippian fields demonstrated that traditional reservoir models built by integrating log, core, DST, and production data from existing wells on 40-acre spacings are unable to delineate karst-induced compartments, thus making 3D-seismic data critical to characterize these fields. Special attribute analyses on 3D data were shown to delineate reservoir compartments and predict those with pay porosities. Further testing of these techniques is required to validate their applicability in other Mississippian reservoirs. This study shows that detailed reservoir characterization and simulation on geomodels developed by integrating wireline log, core, petrophysical, production and pressure, and 3D-seismic data enables better evaluation of a candidate field for horizontal infill applications. In addition to reservoir compartmentalization, two factors were found to control the economic viability of a horizontal infill well in a mature Mississippian field: (a) adequate reservoir pressure support, and (b) an average well spacing greater than 40-acres.

Saibal Bhattacharya

2005-08-31T23:59:59.000Z

309

CX-008674: Categorical Exclusion Determination | Department of Energy  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

74: Categorical Exclusion Determination 74: Categorical Exclusion Determination CX-008674: Categorical Exclusion Determination ATK - A High Efficiency Inertial Carbon Dioxide Extraction System CX(s) Applied: A9, B3.6 Date: 07/01/2011 Location(s): New York, Pennsylvania Offices(s): Advanced Research Projects Agency-Energy Funding will support small-scale laboratory research, design, fabrication and pilot-scale testing of the Inertial Carbon Dioxide Extraction System (ICES), an aero-thermodynamic inertial separation device for use in carbon capture processes. Funding will also support computational and performance modeling, economic modeling, and commercialization/transition planning for the ICES system under development. CX-008674.pdf More Documents & Publications CX-003144: Categorical Exclusion Determination

310

A comparison of a hierarchy of models for determining energy balance components over vegetation canopies  

SciTech Connect

Several methods for estimating surface energy balance components over a vegetated surface are compared. These include Penman-Monteith, Deardorff, and multilayer canopy (CANWHT) models for evaporation. Measurements taken during the 1991 DOE-sponsored Boardman Area Regional Flux Experiment over a well-irrigated, closed wheat canopy are used in the comparison. The relative performance of each model is then evaluated. It is found that the Penman-Monteith approach using a simple parameterization for stomatal conductance performs best for evaporation flux. The Deardorff model is found to have the best relative performance for sensible heat, while the CANWHT model gives the best results for net radiation and soil heat flux. The Priestley-Taylor model for evaporation and a resistance-analog equation for sensible heat flux are also tested. 35 refs., 9 figs., 4 tabs.

Vogel, C.A.; Baldocchi, D.D.; Luhar, A.K.; Rao, K.S. [National Oceanic and Atmospheric Administration, Oak Ridge, TN (United States)

1995-10-01T23:59:59.000Z

311

NETL: Carbon Storage  

NLE Websites -- All DOE Office Websites (Extended Search)

Carbon Sequestration Partnerships Regional Carbon Sequestration Partnership (RCSP) Programmatic Points of Contact Carbon Storage Program Infrastructure Coordinator Carbon Storage...

312

Carbon Cycle 2.0  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Carbon Cycle 2.0 Carbon Cycle 2.0 Pioneering science for sustainable energy solutions Artificial Photosynthesis Energy Storage Combustion Carbon Capture & Storage Developing World Efficiency Photovoltaics Biofuels Energy Analysis Climate Modeling Carbon Cycle 2.0 is... 1. A vision for * a global energy system integrated with the Earth's natural carbon cycles * an interactive Berkeley Lab environment with a shared sense of purpose 2. A program development plan that will allow us to deepen our capabilities and provide more opportunities to have impact 3. An attempt to integrate our basic research with applications using models of technology deployment constraints 4. Set of internal activities aimed at priming the effort

313

A Comparison of a Hierarchy of Models for Determining Energy Balance Components over Vegetation Canopies  

Science Conference Proceedings (OSTI)

Several methods for estimating surface energy balance components over a vegetated surface are compared. These include Penman-Monteith, Deardorff, and multilayer canopy (CANWHT) models for evaporation. Measurements taken during the 1991 DOE-...

Christoph A. Vogel; Dennis D. Baldocchi; Ashok K. Luhar; K. Shankar Rao

1995-10-01T23:59:59.000Z

314

An Objective Method for Determining the Generalized Transport Tensor for Two-Dimensional Eulerian Models  

Science Conference Proceedings (OSTI)

An objective method for deriving the components of a generalized transport tensor for a two-dimensional model is presented. The method uses representative meridional and vertical velocities and thermodynamic scalars at a uniform grid to reduce ...

Edwin F. Danielsen

1981-07-01T23:59:59.000Z

315

Determination of the proper operating range for the CAFCA IIB fuel cycle model  

E-Print Network (OSTI)

The fuel cycle simulation tool, CAFCA II was previously modified to produce the most recent version, CAFCA IIB. The code tracks the mass distribution of transuranics in the fuel cycle in one model and also projects costs ...

Warburton, Jamie (Jamie L.)

2007-01-01T23:59:59.000Z

316

Shelf life determination using sensory evaluation scores: A general Weibull modeling approach  

Science Conference Proceedings (OSTI)

Sensory evaluations to determine the shelf life of food products are routinely conducted in food experimentation as a part of each product development program. In such experiments, trained panelists are asked to judge food attributes by reference to ... Keywords: Maximum likelihood, Sensory evaluations, Shelf life, Weibull distribution

Marta A. Freitas; Josenete C. Costa

2006-12-01T23:59:59.000Z

317

CX-000462: Categorical Exclusion Determination | Department of Energy  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

2: Categorical Exclusion Determination 2: Categorical Exclusion Determination CX-000462: Categorical Exclusion Determination Modeling Carbon Dioxide Sequestration in Saline Aquifer and Depleted Oil Reservoir to Evaluate Regional Carbon Dioxide Sequestration Potential of Ozark Plateau Aquifer System, South-Central Kansas CX(s) Applied: B3.1, A9 Date: 12/11/2009 Location(s): Lawrence, Kansas Office(s): Fossil Energy, National Energy Technology Laboratory Characterize the Ozark Plateau Aquifer System (OPAS) in an area covering approximately 17 counties in south-central Kansas in order to estimate its potential for carbon dioxide sequestration. DOCUMENT(S) AVAILABLE FOR DOWNLOAD CX-000462.pdf More Documents & Publications CX-002613: Categorical Exclusion Determination CX-002612: Categorical Exclusion Determination

318

CX-002611: Categorical Exclusion Determination | Department of Energy  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

1: Categorical Exclusion Determination 1: Categorical Exclusion Determination CX-002611: Categorical Exclusion Determination Modeling Carbon Dioxide Sequestration in Saline Aquifer and Depleted Oil Reservoir to Evaluate Regional Carbon Dioxide Sequestration Potential of Ozark Plateau Aquifer System, South-Central Kansas CX(s) Applied: B3.1, A9 Date: 12/11/2009 Location(s): Manhattan, Kansas Office(s): Fossil Energy, National Energy Technology Laboratory Characterize the Ozark Plateau Aquifer System (OPAS) in an area covering approximately 17 counties in south-central Kansas in order to estimate its potential for carbon dioxide sequestration. DOCUMENT(S) AVAILABLE FOR DOWNLOAD CX-002611.pdf More Documents & Publications CX-002613: Categorical Exclusion Determination CX-002612: Categorical Exclusion Determination

319

CX-002610: Categorical Exclusion Determination | Department of Energy  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

0: Categorical Exclusion Determination 0: Categorical Exclusion Determination CX-002610: Categorical Exclusion Determination Modeling Carbon Dioxide Sequestration in Saline Aquifer and Depleted Oil Reservoir to Evaluate Regional Carbon Dioxide Sequestration Potential of Ozark Plateau Aquifer System, South-Central Kansas CX(s) Applied: B3.1, A9 Date: 12/11/2009 Location(s): Sumner County, Kansas Office(s): Fossil Energy, National Energy Technology Laboratory Characterize the Ozark Plateau Aquifer System (OPAS) in an area covering approximately 17 counties in south-central Kansas in order to estimate its potential for carbon dioxide sequestration. DOCUMENT(S) AVAILABLE FOR DOWNLOAD CX-002610.pdf More Documents & Publications CX-002613: Categorical Exclusion Determination CX-002612: Categorical Exclusion Determination

320

Simplified model for determining local heat flux boundary conditions for slagging wall  

SciTech Connect

In this work, two models for calculating heat transfer through a cooled vertical wall covered with a running slag layer are investigated. The first one relies on a discretization of the velocity equation, and the second one relies on an analytical solution. The aim is to find a model that can be used for calculating local heat flux boundary conditions in computational fluid dynamics (CFD) analysis of such processes. Two different cases where molten deposits exist are investigated: the black liquor recovery boiler and the coal gasifier. The results show that a model relying on discretization of the velocity equation is more flexible in handling different temperature-viscosity relations. Nevertheless, a model relying on an analytical solution is the one fast enough for a potential use as a CFD submodel. Furthermore, the influence of simplifications to the heat balance in the model is investigated. It is found that simplification of the heat balance can be applied when the radiation heat flux is dominant in the balance. 9 refs., 7 figs., 10 tabs.

Bingzhi Li; Anders Brink; Mikko Hupa [Aabo Akademi University, Turku (Finland). Process Chemistry Centre

2009-07-15T23:59:59.000Z

Note: This page contains sample records for the topic "determination modeling carbon" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


321

Reconciling estimates of the contemporary North American carbon balance among terrestrial biosphere models, atmospheric inversions and a new approach for estimating net ecosystem exchange from inventory-based data  

Science Conference Proceedings (OSTI)

While fossil fuel emissions are calculated with relatively high precision, understanding the fate of those emissions with respect to sequestration in terrestrial ecosystems requires data and methods that can reduce uncertainties in the diagnosis of land-based CO2 sinks. The wide range in the land surface flux estimates is related to a number of factors, but most generally because of the different methodologies used to develop estimates of carbon stocks and flux, and the uncertainties inherent in each approach. The alternative approaches to estimating continental scale carbon fluxes that we explored here can be broadly classified as applying a top-down or bottom-up perspective. Top-down approaches calculate land-atmosphere carbon fluxes based on atmospheric budgets and inverse modeling. Bottom-up approaches rely primarily on measurements of carbon stock changes (the inventory approach) or on spatially distributed simulations of carbon stocks and/or fluxes using process-based modeling (the forward modelapproach).

Hayes, D. J.; Turner, D. P.; Stinson, Graham; McGuire, A. David; Wei, Yaxing; West, Tristram O.; Heath, L.; deJong, B.; McConkey, Brian; Birdsey, Richard A.; Kurz, Werner; Jacobson, Andy; Huntzinger, Deborah N.; Pan, Y.; Post, W. M.; Cook, R. B.

2012-04-02T23:59:59.000Z

322

High-Temperature Co-electrolysis of Steam and Carbon Dioxide for Direct Production of Syngas; Equilibrium Model and Single-Cell Tests  

DOE Green Energy (OSTI)

An experimental study has been completed to assess the performance of single solid-oxide electrolysis cells operating over a temperature range of 800 to 850ºC in the coelectrolysis mode, simultaneously electrolyzing steam and carbon dioxide for the direct production of syngas. The experiments were performed over a range of inlet flow rates of steam, carbon dioxide, hydrogen and nitrogen and over a range of current densities (-0.1 to 0.25 A/cm2) using single electrolyte-supported button electrolysis cells. Steam and carbon dioxide consumption rates associated with electrolysis were measured directly using inlet and outlet dewpoint instrumentation and a gas chromatograph, respectively. Cell operating potentials and cell current were varied using a programmable power supply. Measured values of open-cell potential and outlet gas composition are compared to predictions obtained from a chemical equilibrium coelectrolysis model. Model predictions of outlet gas composition based on an effective equilibrium temperature are shown to agree well with measurements. Cell area-specific resistance values were similar for steam electrolysis and coelectrolysis.

O'Brien, J. E.; Stoots, C. M.; Herring, J. S.; Hartvigsen, J. J.

2007-07-01T23:59:59.000Z

323

High-Temperature Co-electrolysis of Carbon Dioxide and Steam for the Production of Syngas; Equilibrium Model and Single-Cell Tests  

DOE Green Energy (OSTI)

An experimental study has been completed to assess the performance of single solid-oxide electrolysis cells operating over a temperature range of 800 to 850ºC in the coelectrolysis mode, simultaneously electrolyzing steam and carbon dioxide for the direct production of syngas. The experiments were performed over a range of inlet flow rates of steam, carbon dioxide, hydrogen and nitrogen and over a range of current densities (-0.1 to 0.25 A/cm2) using single electrolyte-supported button electrolysis cells. Steam and carbon dioxide consumption rates associated with electrolysis were measured directly using inlet and outlet dewpoint instrumentation and a gas chromatograph, respectively. Cell operating potentials and cell current were varied using a programmable power supply. Measured values of open-cell potential and outlet gas composition are compared to predictions obtained from a chemical equilibrium coelectrolysis model. Model predictions of outlet gas composition based on an effective equilibrium temperature are shown to agree well with measurements. Area-specific resistance values were similar for steam electrolysis and coelectrolysis.

J. E. O'Brien; C. M. Stoots; G. L. Hawkes; J. S. Herring; J. J. Hartvigsen

2007-06-01T23:59:59.000Z

324

CX-000265: Categorical Exclusion Determination | Department of Energy  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

65: Categorical Exclusion Determination 65: Categorical Exclusion Determination CX-000265: Categorical Exclusion Determination Experiment-Based Model for the Chemical Interactions between Geothermal Rocks, Supercritical Carbon Dioxide and Water CX(s) Applied: A9, B3.6 Date: 12/23/2009 Location(s): Santa Clara, California Office(s): Energy Efficiency and Renewable Energy, Golden Field Office Symyx Technologies would design and develop a geochemical model that simulates an Enhanced Geothermal System reservoir. The model would develop a foundation in theory and measurement of physical and chemical interactions between minerals, rocks, carbon dioxide and water. DOCUMENT(S) AVAILABLE FOR DOWNLOAD CX-000265.pdf More Documents & Publications CX-003343: Categorical Exclusion Determination CX-000264: Categorical Exclusion Determination

325

Mineral Sequestration of Carbon Dixoide in a Sandstone-Shale System  

E-Print Network (OSTI)

relevant to geologic carbon sequestration. 2002 GeologicalNational Conference on Carbon Sequestration. Washington, DC.model for geological carbon sequestration, 2002 Geological

Xu, Tianfu; Apps, John A.; Pruess, Karsten

2004-01-01T23:59:59.000Z

326

Carbon sequestration with enhanced gas recovery: Identifying candidate sites for pilot study  

E-Print Network (OSTI)

Process modeling of carbon sequestration with enhanced gas2001. Reichle, D. et al.. Carbon sequestration research andCarbon Sequestration with Enhanced Gas Recovery: Identifying

Oldenburg, C.M.; Benson, S.M.

2001-01-01T23:59:59.000Z

327

Kalman-filter model for determining block and trickle SNM losses  

Science Conference Proceedings (OSTI)

This paper describes an integrated decision procedure for deciding whether a diversion of SNM has occurred. Two possible types of diversion are considered: a block loss during a single time period and a cumulative trickle loss over several time periods. The methodology used is based on a compound Kalman filter model. Numerical examples illustrate our approach.

Barlow, R.E.; Durst, M.J.; Smiriga, N.G.

1982-07-01T23:59:59.000Z

328

Aspects of CFC relative ozone destruction efficiencies determined in the LLNL 2-D model  

Science Conference Proceedings (OSTI)

We have investigated the efficiency of surface emission of several individual chlorofluorocarbons (CFCs) and hydrogen-containing chlorofluorocarbons (HCFCs) for reducing the calculated steady state total ozone column in both one- and two-dimensional models, relative to the effects of CFC-11 (CFCl/sub 3/) emission. We find that CFC and HCFC relative efficiencies can vary over two orders of magnitude, mostly as a result of atmospheric lifetimes. For CFCs and HCFCs with long stratospheric lifetimes the calculated efficiency is also reduced by the effects of lower and mid stratospheric photochemistry. Ozone in this region changes according to the net effect of changing rates of oxygen photolysis, direct chlorine-catalyzed ozone loss and interference by active chlorine species in the nitrogen oxide-catalyzed ozone loss process. In these cases, the relative efficiencies show a marked latitudinal dependence, being larger at high latitudes and smaller at lower latitudes. Additionally in these cases, the one-dimensional model appears to overestimate the globally and annually averaged result that is obtained from the two-dimensional model. These considerations should be taken into account when quantities similar to the relative efficiency defined here are applied to CFC production and emission decisions. 6 refs., 4 figs., 1 tab.

Connell, P.; Grant, K.; Wuebbles, D.

1988-08-01T23:59:59.000Z

329

High-resolution modeling of the western North American power system demonstrates low-cost and low-carbon futures  

E-Print Network (OSTI)

Administration, 2008). A number of low- carbon power generation technologies are available today, but many-rated by their forced outage rates to represent the amount of power generation capacity that is available on average). Rather, it does so indirectly, by changing the relative costs of power generating technologies

Kammen, Daniel M.

330

Determination of Cryolite Ratio of Aluminum Electrolytes  

Science Conference Proceedings (OSTI)

The Applicability of Carbon Capture and Sequestration in Primary Aluminium Smelters · The Determination of Pot Current Distribution by Measuring Magnetic ...

331

A model for determining when an analysis contains sufficient detail to provide adequate NEPA coverage for a proposed action  

SciTech Connect

Neither the National Environmental Policy Act (NEPA) nor its subsequent regulations provide substantive guidance for determining the Level of detail, discussion, and analysis that is sufficient to adequately cover a proposed action. Yet, decisionmakers are routinely confronted with the problem of making such determinations. Experience has shown that no two decisionmakers are Likely to completely agree on the amount of discussion that is sufficient to adequately cover a proposed action. one decisionmaker may determine that a certain Level of analysis is adequate, while another may conclude the exact opposite. Achieving a consensus within the agency and among the public can be problematic. Lacking definitive guidance, decisionmakers and critics alike may point to a universe of potential factors as the basis for defending their claim that an action is or is not adequately covered. Experience indicates that assertions are often based on ambiguous opinions that can be neither proved nor disproved. Lack of definitive guidance slows the decisionmaking process and can result in project delays. Furthermore, it can also Lead to inconsistencies in decisionmaking, inappropriate Levels of NEPA documentation, and increased risk of a project being challenged for inadequate coverage. A more systematic and less subjective approach for making such determinations is obviously needed. A paradigm for reducing the degree of subjectivity inherent in such decisions is presented in the following paper. The model is specifically designed to expedite the decisionmaking process by providing a systematic approach for making these determination. In many cases, agencies may find that using this model can reduce the analysis and size of NEPA documents.

Eccleston, C.H.

1994-11-01T23:59:59.000Z

332

Determination of Electrochemical Performance and Thermo-Mechanical-Chemical Stability of SOFCs from Defect Modeling  

DOE Green Energy (OSTI)

This research was focused on two distinct but related issues. The first issue concerned using defect modeling to understand the relationship between point defect concentration and the electrochemical, thermo-chemical and mechano-chemical properties of typical solid oxide fuel cell (SOFC) materials. The second concerned developing relationships between the microstructural features of SOFC materials and their electrochemical performance. To understand the role point defects play in ceramics, a coherent analytical framework was used to develop expressions for the dependence of thermal expansion and elastic modulus on point defect concentration in ceramics. These models, collectively termed the continuum-level electrochemical model (CLEM), were validated through fits to experimental data from electrical conductivity, I-V characteristics, elastic modulus and thermo-chemical expansion experiments for (nominally pure) ceria, gadolinia-doped ceria (GDC) and yttria-stabilized zirconia (YSZ) with consistently good fits. The same values for the material constants were used in all of the fits, further validating our approach. As predicted by the continuum-level electrochemical model, the results reveal that the concentration of defects has a significant effect on the physical properties of ceramic materials and related devices. Specifically, for pure ceria and GDC, the elastic modulus decreased while the chemical expansion increased considerably in low partial pressures of oxygen. Conversely, the physical properties of YSZ remained insensitive to changes in oxygen partial pressure within the studied range. Again, the findings concurred exactly with the predictions of our analytical model. Indeed, further analysis of the results suggests that an increase in the point defect content weakens the attractive forces between atoms in fluorite-structured oxides. The reduction treatment effects on the flexural strength and the fracture toughness of pure ceria were also evaluated at room temperature. The results reveal that the flexural strength decreases significantly after heat treatment in very low oxygen partial pressure environments; however, in contrast, fracture toughness is increased by 30-40% when the oxygen partial pressure was decreased to 10{sup -20} to 10{sup -22} atm range. Fractographic studies show that microcracks developed at 800 oC upon hydrogen reduction are responsible for the decreased strength. To understand the role of microstructure on electrochemical performance, electrical impedance spectra from symmetric LSM/YSZ/LSM cells was de-convoluted to obtain the key electrochemical components of electrode performance, namely charge transfer resistance, surface diffusion of reactive species and bulk gas diffusion through the electrode pores. These properties were then related to microstructural features, such as triple-phase boundary length and tortuosity. From these experiments we found that the impedance due to oxygen adsorption obeys a power law with pore surface area, while the impedance due to charge transfer is found to obey a power-law with respect to triple phase boundary length. A model based on kinetic theory explaining the power-law relationships observed was then developed. Finally, during our EIS work on the symmetric LSM/YSZ/LSM cells a technique was developed to improve the quality of high-frequency impedance data and their subsequent de-convolution.

Eric Wachsman; Keith L. Duncan

2006-09-30T23:59:59.000Z

333

PREDICTING TEMPERATURE BEHAVIOR IN CARBONATE ACIDIZING TREATMENTS  

E-Print Network (OSTI)

To increase the successful rate of acid stimulation, a method is required to diagnose the effectiveness of stimulation which will help us to improve stimulation design and decide whether future action, such as diversion, is needed. For this purpose, it is important to know how much acid enters each layer in a multilayer carbonate formation and if the low-permeability layer is treated well. This work develops a numerical model to determine the temperature behavior for both injection and flow-back situations. An important phenomenon in this process is the heat generated by reaction, affecting the temperature behavior significantly. The result of the thermal model showed significant temperature effects caused by reaction, providing a mechanism to quantitatively determine the acid flow profile. Based on this mechanism, a further inverse model can be developed to determine the acid distribution in each layer.

Tan, Xuehao

2009-05-01T23:59:59.000Z

334

Modeling the determinants of the social impacts of agricultural development projects  

SciTech Connect

In an attempt to help policy-makers improve the social sustainability of development projects, this study identifies the key determinants of farmers' attitudes relating to the social impacts of the floodwater spreading project (FWSP) on the Gareh-Bygone plain in Iran. In order to analyze the links between the various factors that affect the experience of social impact, a theoretical framework was developed. Stratified random sampling was used to survey 138 farm households from the four villages in the region. One male and one female from each house were interviewed face-to-face using a questionnaire, resulting in a total of 276 interviews. Structural factors were found to be the largest contribution to stakeholders' attitudes relating to the social impacts of the project. Results from a cluster analysis suggested that the level of floodwater information, level of participation, water access, ownership change, and environmental worldview were the most important factors explaining attitude towards social impact of the FWSP.

Ahmadvand, Mostafa, E-mail: Ahmadvand_2000@yahoo.co [Department of Rural Development Management, Faculty of Agriculture, Yasouj University, Yasouj (Iran, Islamic Republic of); Karami, Ezatollah, E-mail: ekarami@shirazu.ac.i [Department of Agricultural Extension and Education, College of Agriculture, Shiraz University, Shiraz (Iran, Islamic Republic of); Iman, Mohammad Taghi, E-mail: Iman@shirazu.ac.i [Department of Sociology, School of Social Sciences, Shiraz University, Shiraz (Iran, Islamic Republic of)

2011-01-15T23:59:59.000Z

335

Experimental determination and thermodynamic modeling of the Ni-Re binary system  

Science Conference Proceedings (OSTI)

The phase diagram of the Ni-Re binary system has been partially reinvestigated by chemical, structural and thermal characterization of the arc melted alloys. The experimental results obtained during the present investigation were combined with the literature data and a new phase diagram of the Ni-Re binary system is proposed. In comparison with the Ni-Re phase diagram proposed by Nash et al. in 1985 [1], significant differences in the homogeneity domains, freezing ranges and peritectic reaction temperature were evidenced. On the other hand, thermodynamic modeling of the studied system by using the new experimental information has also been carried out with the help of the CALPHAD method. The calculated Ni-Re phase diagram showed a good agreement with the selected experimental information. - Graphical abstract: Ni-Re phase diagram according to the present study. Highlights: Black-Right-Pointing-Pointer Re-investigation of the Ni-Re phase diagram. Black-Right-Pointing-Pointer Extended phase field of the hcp phase. Black-Right-Pointing-Pointer Different freezing ranges and peritectic reaction temperature. Black-Right-Pointing-Pointer Thermodynamic modeling of the studied system by using the CALPHAD method.

Yaqoob, Khurram [Chimie Metallurgique des Terres Rares (CMTR), Institut de Chimie et des Materiaux Paris-Est (ICMPE), 2-8 rue Henri Dunant, 94320 Thiais Cedex (France)] [Chimie Metallurgique des Terres Rares (CMTR), Institut de Chimie et des Materiaux Paris-Est (ICMPE), 2-8 rue Henri Dunant, 94320 Thiais Cedex (France); Joubert, Jean-Marc, E-mail: jean-marc.joubert@icmpe.cnrs.fr [Chimie Metallurgique des Terres Rares (CMTR), Institut de Chimie et des Materiaux Paris-Est (ICMPE), 2-8 rue Henri Dunant, 94320 Thiais Cedex (France)] [Chimie Metallurgique des Terres Rares (CMTR), Institut de Chimie et des Materiaux Paris-Est (ICMPE), 2-8 rue Henri Dunant, 94320 Thiais Cedex (France)

2012-12-15T23:59:59.000Z

336

Modeling LIDAR Detection of Biological Aerosols to Determine Optimum Implementation Strategy  

Science Conference Proceedings (OSTI)

This report summarizes work performed for a larger multi-laboratory project named the Background Interferent Measurement and Standards project. While originally tasked to develop algorithms to optimize biological warfare agent detection using UV fluorescence LIDAR, the current uncertainties in the reported fluorescence profiles and cross sections the development of any meaningful models. It was decided that a better approach would be to model the wavelength-dependent elastic backscattering from a number of ambient background aerosol types, and compare this with that generated from representative sporulated and vegetative bacterial systems. Calculations in this report show that a 266, 355, 532 and 1064 nm elastic backscatter LIDAR experiment will allow an operator to immediately recognize when sulfate, VOC-based or road dust (silicate) aerosols are approaching, independent of humidity changes. It will be more difficult to distinguish soot aerosols from biological aerosols, or vegetative bacteria from sporulated bacteria. In these latter cases, the elastic scattering data will most likely have to be combined with UV fluorescence data to enable a more robust categorization.

Sheen, David M.; Aker, Pam M.

2007-09-19T23:59:59.000Z

337

PlaneCarbon | Open Energy Information  

Open Energy Info (EERE)

PlaneCarbon PlaneCarbon Jump to: navigation, search Name PlaneCarbon Address 9149 N. 109th Place Place Scottsdale, Arizona Zip 85259 Sector Carbon Product PlaneCarbon Year founded 2002 Number of employees 1-10 Phone number 480-205-0881 Website http://iteknowledgies.com/tran References Iteknowledgies[1] LinkedIn Connections CrunchBase Profile No CrunchBase profile. Create one now! TODO: Determine if all of this content is appropriate and has a neutral point of view. PlaneCarbon, a division of Iteknowledgies International, is a company based in Scottsdale, Arizona. PlaneCarbon purchases carbon credits to achieve carbon neutral operation of your aircraft based on the average utilization of a specific aircraft in hours per year and then calculating the amount of fuel burned and purchasing offsetting carbon credits to achieve carbon

338

Integrated Multi-Well Reservoir and Decision Model to Determine Optimal Well Spacing in Unconventional Gas Reservoirs  

E-Print Network (OSTI)

Optimizing well spacing in unconventional gas reservoirs is difficult due to complex heterogeneity, large variability and uncertainty in reservoir properties, and lack of data that increase the production uncertainty. Previous methods are either suboptimal because they do not consider subsurface uncertainty (e.g., statistical moving-window methods) or they are too time-consuming and expensive for many operators (e.g., integrated reservoir characterization and simulation studies). This research has focused on developing and extending a new technology for determining optimal well spacing in tight gas reservoirs that maximize profitability. To achieve the research objectives, an integrated multi-well reservoir and decision model that fully incorporates uncertainty was developed. The reservoir model is based on reservoir simulation technology coupled with geostatistical and Monte Carlo methods to predict production performance in unconventional gas reservoirs as a function of well spacing and different development scenarios. The variability in discounted cumulative production was used for direct integration of the reservoir model with a Bayesian decision model (developed by other members of the research team) that determines the optimal well spacing and hence the optimal development strategy. The integrated model includes two development stages with a varying Stage-1 time span. The integrated tools were applied to an illustrative example in Deep Basin (Gething D) tight gas sands in Alberta, Canada, to determine optimal development strategies. The results showed that a Stage-1 length of 1 year starting at 160-acre spacing with no further downspacing is the optimal development policy. It also showed that extending the duration of Stage 1 beyond one year does not represent an economic benefit. These results are specific to the Berland River (Gething) area and should not be generalized to other unconventional gas reservoirs. However, the proposed technology provides insight into both the value of information and the ability to incorporate learning in a dynamic development strategy. The new technology is expected to help operators determine the combination of primary and secondary development policies early in the reservoir life that profitably maximize production and minimize the number of uneconomical wells. I anticipate that this methodology will be applicable to other tight and shale gas reservoirs.

Ortiz Prada, Rubiel Paul

2010-12-01T23:59:59.000Z

339

Forward model calculations for determining isotopic compositions of materials used in a radiological dispersal device  

E-Print Network (OSTI)

In the event that a radiological dispersal device (RDD) is detonated in the U.S. or near U.S. interests overseas, it will be crucial that the actors involved in the event can be identified quickly. If irradiated nuclear fuel is used as the dispersion material for the RDD, it will be beneficial for law enforcement officials to quickly identify where the irradiated nuclear fuel originated. One signature which may lead to the identification of the spent fuel origin is the isotopic composition of the RDD debris. The objective of this research was to benchmark a forward model methodology for predicting isotopic composition of spent nuclear fuel used in an RDD while at the same time optimizing the fidelity of the model to reduce computational time. The code used in this study was Monteburns-2.0. Monteburns is a Monte Carlo based neutronic code utilizing both MCNP and ORIGEN. The size of the burnup step used in Monteburns was tested and found to converge at a value of 3,000 MWd/MTU per step. To ensure a conservative answer, 2,500 MWd/MTU per step was used for the benchmarking process. The model fidelity ranged from the following: 2-dimensional pin cell, multiple radial-region pin cell, modified pin cell, 2D assembly, and 3D assembly. The results showed that while the multi-region pin cell gave the highest level of accuracy, the difference in uncertainty between it and the 2D pin cell (0.07% for 235U) did not warrant the additional computational time required. The computational time for the multiple radial-region pin cell was 7 times that of the 2D pin cell. For this reason, the 2D pin cell was used to benchmark the isotopics with data from other reactors. The reactors from which the methodology was benchmarked were Calvert Cliffs Unit #1, Takahama Unit #3, and Trino Vercelles. Calvert Cliffs is a pressurized water reactor (PWR) using Combustion Engineering 14??14 assemblies. Takahama is a PWR using Mitsubishi Heavy Industries 17??17 assemblies. Trino Vercelles is a PWR using non-standard lattice assemblies. The measured isotopic concentrations from all three of the reactors showed good agreement with the calculated values.

Burk, David Edward

2005-05-01T23:59:59.000Z

340

Models for the lens and source of B0218+357 - A LensClean approach to determine H0  

E-Print Network (OSTI)

B0218+357 is one of the most promising systems to determine the Hubble constant from gravitational lenses. Consisting of two bright resolved images plus an Einstein ring, it provides better constraints for the mass model than other systems. The main problem left until now was the poorly determined position of the lensing galaxy. After presenting results from classical lens modelling, we apply our improved version of LensClean which utilizes the Einstein ring for lens modelling purposes. The primary result using isothermal models is a well defined lens position which allows the first reliable measurement of the Hubble constant from this system. The result of H0=(78+-6) km/s/Mpc (2 sigma) is high compared with other lenses but compatible with the HST key project and WMAP results. We furthermore discuss effects of different radial mass profiles. The power-law exponent of the potential is constrained by VLBI data to be beta=1.04+-0.02, very close to isothermal. The effect on H0 is expected to be very small. We also present a composite map (lensed and unlensed) which shows the rich structure of B0218+357 on scales from milli-arcseconds to arcseconds. Finally we use a comparison of observations at different frequencies to investigate the question of possible weakening of one of the images by propagation effects and/or source shifts with frequency. The data clearly favour the model of significant extinction without noticeable source position shifts. The technical details of our variant of the LensClean method are presented in the accompanying Paper I.

O. Wucknitz; A. D. Biggs; I. W. A. Browne

2003-12-10T23:59:59.000Z

Note: This page contains sample records for the topic "determination modeling carbon" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


341

Carbon Cycle  

NLE Websites -- All DOE Office Websites (Extended Search)

Carbon Cycle Carbon Cycle Latest Global Carbon Budget Estimates Including CDIAC Estimates Terrestrial Carbon Management Data Sets and Analyses Carbon Dioxide Emissions from Fossil-Fuel Consumption and Cement Manufacture, (2011) Annual Fossil-Fuel CO2 Emissions: Mass of Emissions Gridded by One Degree Latitude by One Degree Longitude (2012) Monthly Fossil-Fuel CO2 Emissions: Mass of Emissions Gridded by One Degree Latitude by One Degree Longitude (2012) Annual Fossil-Fuel CO2 Emissions: Global Stable Carbon Isotopic Signature (2012) Monthly Fossil-Fuel CO2 Emissions: Isomass (δ 13C) of Emissions Gridded by One Degree Latitude by One Degree Longitude (2012) AmeriFlux - Terrestrial Carbon Dioxide, Water Vapor, and Energy Balance Measurements Estimates of Monthly CO2 Emissions and Associated 13C/12C Values

342

Carbon Isotopes  

NLE Websites -- All DOE Office Websites (Extended Search)

Atmospheric Trace Gases » Carbon Isotopes Atmospheric Trace Gases » Carbon Isotopes Carbon Isotopes Gateway Pages to Isotopes Data Modern Records of Carbon and Oxygen Isotopes in Atmospheric Carbon Dioxide and Carbon-13 in Methane 800,000 Deuterium Record and Shorter Records of Various Isotopic Species from Ice Cores Carbon-13 13C in CO Measurements from Niwot Ridge, Colorado and Montana de Oro, California (Tyler) 13C in CO2 NOAA/CMDL Flask Network (White and Vaughn) CSIRO GASLAB Flask Network (Allison, Francey, and Krummel) CSIRO in situ measurements at Cape Grim, Tasmania (Francey and Allison) Scripps Institution of Oceanography (Keeling et al.) 13C in CH4 NOAA/CMDL Flask Network (Miller and White) Northern & Southern Hemisphere Sites (Quay and Stutsman) Northern & Southern Hemisphere Sites (Stevens)

343

Determination of the effects caused by different polymers on coal fluidity during carbonization using high-temperature {sup 1}H NMR and rheometry  

SciTech Connect

The effects of blending polyethylene (PE), polystyrene (PS), poly(ethyleneterephthalate) (PET), a flexible polyurethane (FPU), and a car shredded fluff waste (CSF) on fluidity development of a bituminous coal during carbonization have been studied by means of high-torque, small-amplitude controlled-strain rheometry and in situ high-temperature {sup 1}H NMR spectroscopy. The most detrimental effects were caused by PET and PS, which completely destroyed the fluidity of the coal. The CSF had a deleterious effect on coal fluidity similar to that of PET, although the deleterious effect on the viscoelastic properties of the coal were less pronounced than those of PET and PS. On the contrary, the addition of 10 wt % PE caused a slight reduction in the concentration of fluid hydrogen and an increase in the minimum complex viscosity, and the addition of 10 wt % FPU reduced the concentration of fluid hydrogen without changing the viscoelastic properties of the coal. Although these results suggest that these two plastics could potentially be used as additives in coking blends without compromising coke porosity, it was found that the semicoke strengths were reduced by adding 2 wt % FPU and 5 wt % PE. Therefore, it is unlikely that more than 2 wt % of a plastic waste could be added to a coal blend without deterioration in coke quality. 35 refs., 11 figs., 3 tabs.

Miguel Castro Diaz; Lucky Edecki; Karen M. Steel; John W. Patrick; Colin E. Snape [Nottingham University, Nottingham (United Kingdom). Nottingham Fuel and Energy Centre, School of Chemical, Environmental and Mining Engineering

2008-01-15T23:59:59.000Z

344

Carbon/Carbon  

Science Conference Proceedings (OSTI)

Then the focus is made on an integrated multi-scale model of pyrocarbon infiltration from pure propane, which compares favorably to actual CVI experiments.

345

Numerical modeling of carbon dioxide sequestration on the rate of pressure solution creep in limestone: Preliminary results  

E-Print Network (OSTI)

When carbon dioxide (CO2) is injected into an aquifer or a depleted geological reservoir, its dissolution into solution results in acidification of the pore waters. As a consequence, the pore waters become more reactive, which leads to enhanced dissolution-precipitation processes and a modification of the mechanical and hydrological properties of the rock. This effect is especially important for limestones given that the solubility and reactivity of carbonates is strongly dependent on pH and the partial pressure of CO2. The main mechanism that couples dissolution, precipitation and rock matrix deformation is commonly referred to as intergranular pressure solution creep (IPS) or pervasive pressure solution creep (PSC). This process involves dissolution at intergranular grain contacts subject to elevated stress, diffusion of dissolved material in an intergranular fluid, and precipitation in pore spaces subject to lower stress. This leads to an overall and pervasive reduction in porosity due to both grain indent...

Renard, Francois; Hellmann, Roland; Collombet, Marielle; Guen, Yvi Le

2008-01-01T23:59:59.000Z

346

Pore-Level Modeling of Carbon Dioxide Sequestration in Oil Fields: A study of viscous and buoyancy forces  

NLE Websites -- All DOE Office Websites (Extended Search)

Sequestration in Oil Fields: A Sequestration in Oil Fields: A study of viscous and buoyancy forces Grant S. Bromhal, U.S. Department of Energy, National Energy Technology Laboratory, Morgantown, WV 26507-0880, gbromhal@netl.doe.gov, M. Ferer, Department of Physics, West Virginia University, and Duane H. Smith, U.S. Department of Energy, National Energy Technology Laboratory, Morgantown, WV 26507-0880 Underground injection of carbon dioxide for enhanced oil recovery (EOR) is a common practice in the oil and gas industry and has often been cited as a proven method of sequestering CO 2 (US DOE, 1999). Of all sequestration methods, this is probably the best understood, as carbon dioxide has been used in the oil industry for many years. Additionally, most oil fields have been relatively well characterized geologically, and

347

Determining the Effect of Concerted Elimination Reactions in the Pyrolysis of Lignin Using Model Compounds  

DOE Green Energy (OSTI)

Lignin pyrolysis is a significant impediment in forming liquid fuel from biomass. Lignin pyrolyzes at a higher temperature than other biomass components (ie cellulose, hemicellulose) and tends to form radicals which lead to cross linking and ultimately char formation. A primary step in advances biomass-to-fuel technology will be to discover mechanisms that can disassemble lignin at lower temperatures and depolymerize lignin into more stable products. We have investigated the thermochemistry of the various inter-linkage units found in lignin ({beta}-O4, {alpha}-O4, {beta}-{beta}, {beta}-O5, etc) using electronic structure calculations at the M06-2x/6-311++G(d,p) on a series of dimer model compounds. In addition to the usually-assumed bond homolysis reactions, we have investigated a variety of concerted elimination pathways that will tend to produce closed-shell stable products. Such a bottom-up approach could aid in the targeted development of catalysts that produce more desirable products under less severe reactor conditions.

Robichaud, D.; Clark, J.; Nimlos, M.

2012-01-01T23:59:59.000Z

348

CX-001159: Categorical Exclusion Determination | Department of...  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Determination CX-001159: Categorical Exclusion Determination An Evaluation of the Carbon Sequestration Potential of the Cambro-Ordovician Strata of the Illinois and...

349

CX-006036: Categorical Exclusion Determination | Department of...  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Exclusion Determination CX-006036: Categorical Exclusion Determination Big Sky Regional Carbon Sequestration Partnership - Phase III CX(s) Applied: A1, A9, A11 Date: 06132011...

350

CX-001160: Categorical Exclusion Determination | Department of...  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Determination CX-001160: Categorical Exclusion Determination An Evaluation of the Carbon Sequestration Potential of the Cambro-Ordovician Strata of the Illinois and...

351

CX-004777: Categorical Exclusion Determination | Department of...  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Determination CX-004777: Categorical Exclusion Determination Recovery Act: Innovative Carbon Dioxide Sequestration from Flue Gas using an In-Duct Scrubber CX(s) Applied: A9,...

352

CX-008506: Categorical Exclusion Determination | Department of...  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Exclusion Determination CX-008506: Categorical Exclusion Determination Midwest Regional Carbon Sequestration Partnership - Phase Three CX(s) Applied: B3.1, B5.3 Date: 07162012...

353

CX-004393: Categorical Exclusion Determination | Department of...  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Exclusion Determination CX-004393: Categorical Exclusion Determination Evaluation of the Carbon Sequestration Potential of the Cambro-Ordovician Strata of the Illinois & Michigan...

354

CX-000377: Categorical Exclusion Determination | Department of...  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Exclusion Determination CX-000377: Categorical Exclusion Determination Demonstration of Carbon Capture and Sequestration from Steam Methane Reforming Process Gas used for...

355

CX-004776: Categorical Exclusion Determination | Department of...  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Determination CX-004776: Categorical Exclusion Determination Recovery Act: Innovative Carbon Dioxide Sequestration from Flue Gas using an In-Duct Scrubber CX(s) Applied: A9,...

356

CX-001162: Categorical Exclusion Determination | Department of...  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Determination CX-001162: Categorical Exclusion Determination An Evaluation of the Carbon Sequestration Potential of the Cambro-Ordovician Strata of the Illinois and...

357

CX-004778: Categorical Exclusion Determination | Department of...  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Determination CX-004778: Categorical Exclusion Determination Recovery Act: Innovative Carbon Dioxide Sequestration from Flue Gas using an In-Duct Scrubber CX(s) Applied: A9,...

358

CX-000394: Categorical Exclusion Determination | Department of...  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

94: Categorical Exclusion Determination CX-000394: Categorical Exclusion Determination Carbon Capture and Sequestration (by Enhance Oil Recovery) Project Phase 1 CX(s) Applied: A1,...

359

CX-008507: Categorical Exclusion Determination | Department of...  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Exclusion Determination CX-008507: Categorical Exclusion Determination Midwest Regional Carbon Sequestration Partnership - Phase Three CX(s) Applied: B3.1, B5.3 Date: 07162012...

360

CX-000285: Categorical Exclusion Determination | Department of...  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

285: Categorical Exclusion Determination CX-000285: Categorical Exclusion Determination Carbon Capture and Sequestration (by Enhanced Oil Recovery) Project Phase 1 CX(s) Applied:...

Note: This page contains sample records for the topic "determination modeling carbon" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


361

CX-007118: Categorical Exclusion Determination | Department of...  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Exclusion Determination CX-007118: Categorical Exclusion Determination Shallow Carbon Sequestration Demonstration Project CX(s) Applied: B3.1 Date: 10042011...

362

CX-001163: Categorical Exclusion Determination | Department of...  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Determination CX-001163: Categorical Exclusion Determination An Evaluation of the Carbon Sequestration Potential of the Cambro-Ordovician Strata of the Illinois and...

363

CX-003173: Categorical Exclusion Determination | Department of...  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Exclusion Determination CX-003173: Categorical Exclusion Determination Midwest Region Carbon Sequestration Partnership, Phase III Test Well CX(s) Applied: B3.1 Date: 07282010...

364

CX-001161: Categorical Exclusion Determination | Department of...  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Determination CX-001161: Categorical Exclusion Determination An Evaluation of the Carbon Sequestration Potential of the Cambro-Ordovician Strata of the Illinois and...

365

CX-000393: Categorical Exclusion Determination | Department of...  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

3: Categorical Exclusion Determination CX-000393: Categorical Exclusion Determination Carbon Capture and Sequestration (by Enhanced Oil Recovery) Project Phase 1 CX(s) Applied: A1,...

366

CX-009326: Categorical Exclusion Determination | Department of...  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Exclusion Determination CX-009326: Categorical Exclusion Determination Midwest Regional Carbon Sequestration Partnership - Subtask 1.7 CX(s) Applied: B3.1 Date: 09282012...

367

CX-007111: Categorical Exclusion Determination | Department of...  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Exclusion Determination CX-007111: Categorical Exclusion Determination Shallow Carbon Sequestration Demonstration Project (Iatan Generating Station) CX(s) Applied: B3.1...

368

CX-002588: Categorical Exclusion Determination | Department of...  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Exclusion Determination CX-002588: Categorical Exclusion Determination A Novel Biogas Desulfurization Sorbent Technology for Molten Carbonate Fuel Cell-Based Combined Heat...

369

CX-000758: Categorical Exclusion Determination | Department of...  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Determination CX-000758: Categorical Exclusion Determination Carbon Dioxide Conversion to Fuels and Energy CX(s) Applied: B3.6 Date: 02092010 Location(s): Des Plaines,...

370

CX-003172: Categorical Exclusion Determination | Department of...  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

172: Categorical Exclusion Determination CX-003172: Categorical Exclusion Determination RTI International - Novel Non-Aqueous Carbon Dioxide-Solvents and Capture Process CX(s)...

371

CX-003937: Categorical Exclusion Determination | Department of...  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Determination CX-003937: Categorical Exclusion Determination Hawaii Energy Sustainability Program (Subtask 2.4.1: Evaluate Carbonized Biomass Samples) CX(s) Applied: A9,...

372

CX-009472: Categorical Exclusion Determination | Department of...  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Determination CX-009472: Categorical Exclusion Determination Small Molecule Associative Carbon Dioxide Thickeners for Improved Mobility Control CX(s) Applied: A1, B3.6 Date: 10...

373

CX-002495: Categorical Exclusion Determination | Department of...  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Determination CX-002495: Categorical Exclusion Determination Innovative Concepts for Carbon Dioxide Use CX(s) Applied: B3.6 Date: 06022010 Location(s): Alcoa Center,...

374

CX-008266: Categorical Exclusion Determination | Department of...  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Determination CX-008266: Categorical Exclusion Determination Improved Mobility Control in Carbon Dioxide Enhanced Recovery Using SPI Gels CX(s) Applied: B3.6 Date: 05232012...

375

CX-007493: Categorical Exclusion Determination | Department of...  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Exclusion Determination CX-007493: Categorical Exclusion Determination GoM Miocene Carbon Dioxide Site Characterization Mega Transect: High-Resolution 3-dimensional Seismic...

376

CX-005056: Categorical Exclusion Determination | Department of...  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Determination CX-005056: Categorical Exclusion Determination Area of Interest 1, Carbon Dioxide at the Interface: Nature and Dynamics of the ReservoirCaprock Contact and...

377

CX-005057: Categorical Exclusion Determination | Department of...  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Determination CX-005057: Categorical Exclusion Determination Area of Interest 1, Carbon Dioxide at the Interface: Nature and Dynamics of the ReservoirCaprock Contact and...

378

CX-008493: Categorical Exclusion Determination | Department of...  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Categorical Exclusion Determination CX-008493: Categorical Exclusion Determination Liquid Carbon Dioxide Slurry for Feeding Low Rank Coal (LRC) Gasifiers CX(s) Applied: A9 Date:...

379

CX-005622: Categorical Exclusion Determination | Department of...  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Exclusion Determination CX-005622: Categorical Exclusion Determination Skymine Beneficial Carbon Dioxide Use Project, Phase 1 Research and Development CX(s) Applied: A1, A9, A11,...

380

CX-010297: Categorical Exclusion Determination | Department of...  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Determination CX-010297: Categorical Exclusion Determination Improved Mobility Control in Carbon Dioxide Enhanced Recovery Using SPI Gels CX(s) Applied: B3.11 Date: 05032013...

Note: This page contains sample records for the topic "determination modeling carbon" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


381

CX-005247: Categorical Exclusion Determination | Department of...  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

7: Categorical Exclusion Determination CX-005247: Categorical Exclusion Determination Carbon Dioxide Saline Storage Demonstration in Colorado Sedimentary Basins: Applied Studies in...

382

CX-000405: Categorical Exclusion Determination | Department of...  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

5: Categorical Exclusion Determination CX-000405: Categorical Exclusion Determination Carbon Dioxide Capture Using Novel Amine Technology and Sequestration by Injection into the...

383

CX-005455: Categorical Exclusion Determination | Department of...  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

5: Categorical Exclusion Determination CX-005455: Categorical Exclusion Determination Carbon Dioxide Enhanced Oil Production from the Citronelle Oil Field CX(s) Applied: B5.12...

384

CX-006173: Categorical Exclusion Determination | Department of...  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Categorical Exclusion Determination CX-006173: Categorical Exclusion Determination Plains Carbon Dioxide Reduction Partnership (PCOR) Phase III Bell Creek Site CX(s) Applied: B3.1...

385

CX-000383: Categorical Exclusion Determination | Department of...  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Determination CX-000383: Categorical Exclusion Determination Cemex Commercial-Scale Carbon Dioxide Capture and Sequestration for the Cement Industry CX(s) Applied: A1, A9,...

386

CX-002396: Categorical Exclusion Determination | Department of...  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Exclusion Determination CX-002396: Categorical Exclusion Determination Montana Integrated Carbon to Liquids Technology (ICTL) Demonstration Program CX(s) Applied: B3.6 Date:...

387

CX-005826: Categorical Exclusion Determination | Department of...  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Bench-scale experiments to determine chemical processes that could occur in deep wells under carbon dioxide injection conditions, and determine their impact on seal...

388

CX-009388: Categorical Exclusion Determination | Department of...  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Determination CX-009388: Categorical Exclusion Determination Chemical Looping Combustion Technology with carbon dioxide Capture for New and Existing Coal-Fired Power Plants...

389

CX-009387: Categorical Exclusion Determination | Department of...  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Determination CX-009387: Categorical Exclusion Determination Chemical Looping Combustion Technology with carbon dioxide Capture for New and Existing Coal-Fired Power Plants...

390

CX-000381: Categorical Exclusion Determination | Department of...  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Exclusion Determination CX-000381: Categorical Exclusion Determination Microbial and Chemical Enhancement of In-Situ Carbon Mineralization in Geological Formation CX(s) Applied:...

391

CX-003145: Categorical Exclusion Determination | Department of...  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

45: Categorical Exclusion Determination CX-003145: Categorical Exclusion Determination Sustainable Energy Solutions, LLC - Cryogenic Carbon Capture Process CX(s) Applied: B3.6...

392

CX-000460: Categorical Exclusion Determination | Department of...  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

0: Categorical Exclusion Determination CX-000460: Categorical Exclusion Determination Thermal Integration of Carbon Dioxide Compression Processes with Coal-Fired Power Plants...

393

CX-003125: Categorical Exclusion Determination | Department of...  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Determination CX-003125: Categorical Exclusion Determination Codexis, Inc. - Low-Cost Biocatalyst for Acceleration of Energy Efficient Carbon Dioxide Capture Solvents...

394

CX-009344: Categorical Exclusion Determination | Department of...  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Exclusion Determination CX-009344: Categorical Exclusion Determination Intrinsic Fiber Optic Chemical Sensors for Subsurface Detection of carbon dioxide CX(s) Applied:...

395

CX-009343: Categorical Exclusion Determination | Department of...  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Exclusion Determination CX-009343: Categorical Exclusion Determination Intrinsic Fiber Optic Chemical Sensors for Subsurface Detection of carbon dioxide CX(s) Applied:...

396

CX-009345: Categorical Exclusion Determination | Department of...  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Exclusion Determination CX-009345: Categorical Exclusion Determination Intrinsic Fiber Optic Chemical Sensors for Subsurface Detection of carbon dioxide CX(s) Applied:...

397

CX-003339: Categorical Exclusion Determination | Department of...  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Determination CX-003339: Categorical Exclusion Determination Energy Efficient Commercial Refrigeration with Carbon Dioxide Refrigerant and Scroll Expanders CX(s) Applied: B3.6...

398

CX-008673: Categorical Exclusion Determination | Department of...  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Exclusion Determination CX-008673: Categorical Exclusion Determination Columbia - Biofuels from Carbon Dioxide using Ammonia-Oxidizing Bacteria in a Reverse Microbial Fuel Cell...

399

CX-003117: Categorical Exclusion Determination | Department of...  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Determination CX-003117: Categorical Exclusion Determination Columbia University - Biofuels from Carbon Dioxide using Ammonia-Oxidizing Bacteria in a Reverse Microbial Fuel Cell...

400

CX-007588: Categorical Exclusion Determination | Department of...  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Exclusion Determination CX-007588: Categorical Exclusion Determination United States-China Ordos Basin Carbon Capture and Storage Feasibility Project Proposal CX(s) Applied: A9,...

Note: This page contains sample records for the topic "determination modeling carbon" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


401

CX-000586: Categorical Exclusion Determination | Department of...  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Exclusion Determination CX-000586: Categorical Exclusion Determination 25A1455 - Carbon Dioxide Capture with Enzyme Synthetic Analogue Date: 12152009 Location(s):...

402

CX-003564: Categorical Exclusion Determination | Department of...  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Determination CX-003564: Categorical Exclusion Determination Advanced Building Insulation by Carbon Dioxide Foaming Process CX(s) Applied: B3.6 Date: 08242010 Location(s):...

403

CX-000412: Categorical Exclusion Determination | Department of...  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Determination CX-000412: Categorical Exclusion Determination Carbon Dioxide Sealing Capacity: Textural or Compositional Controls? CX(s) Applied: B3.6, A9 Date: 12112009...

404

CX-001353: Categorical Exclusion Determination | Department of...  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Determination CX-001353: Categorical Exclusion Determination Space Geodesy and Geochemistry Applied to the Monitoring, Verification of Carbon Capture and Storage - Kimberlina...

405

CX-001351: Categorical Exclusion Determination | Department of...  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Determination CX-001351: Categorical Exclusion Determination Space Geodesy and Geochemistry Applied to the Monitoring, Verification of Carbon Capture and Storage - Miami CX(s)...

406

CX-003128: Categorical Exclusion Determination | Department of...  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

28: Categorical Exclusion Determination CX-003128: Categorical Exclusion Determination University of Kentucky Research Foundation -A SolventMembrane Hybrid Post-combustion Carbon...

407

CX-010792: Categorical Exclusion Determination | Department of...  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

2: Categorical Exclusion Determination CX-010792: Categorical Exclusion Determination Gulf of Mexico Miocene Carbon Dioxide (CO2) Site Characterization Mega Transect - Task 8 CX(s)...

408

CX-011125: Categorical Exclusion Determination | Department of...  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Determination CX-011125: Categorical Exclusion Determination A New Generation of Building Insulation by Foaming Polymer Blend Materials with Carbon Dioxide CX(s) Applied:...

409

CX-000450: Categorical Exclusion Determination | Department of...  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Exclusion Determination CX-000450: Categorical Exclusion Determination Gulf of Mexico Miocene Carbon Dioxide Site Characterization Mega Transect CX(s) Applied: A9, B3.1...

410

CX-010790: Categorical Exclusion Determination | Department of...  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Exclusion Determination CX-010790: Categorical Exclusion Determination Gulf of Mexico Miocene Carbon Dioxide (CO2) Site Characterization Mega Transect CX(s) Applied: A9,...

411

CX-010792: Categorical Exclusion Determination | Department of...  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Exclusion Determination CX-010792: Categorical Exclusion Determination Gulf of Mexico Miocene Carbon Dioxide (CO2) Site Characterization Mega Transect - Task 8 CX(s)...

412

CX-000442: Categorical Exclusion Determination | Department of...  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Exclusion Determination CX-000442: Categorical Exclusion Determination Gulf of Mexico Miocene Carbon Dioxide Site Characterization Mega Transect CX(s) Applied: A9, A11,...

413

CX-010791: Categorical Exclusion Determination | Department of...  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Exclusion Determination CX-010791: Categorical Exclusion Determination Gulf of Mexico Miocene Carbon Dioxide (CO2) Site Characterization Mega Transect CX(s) Applied: A9,...

414

CX-000444: Categorical Exclusion Determination | Department of...  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Exclusion Determination CX-000444: Categorical Exclusion Determination Gulf of Mexico Miocene Carbon Dioxide Site Characterization Mega Transect CX(s) Applied: A11, B3.1...

415

Determining Plutonium Mass in Spent Fuel with Nondestructive Assay Techniques -- Preliminary Modeling Results Emphasizing Integration among Techniques  

Science Conference Proceedings (OSTI)

There are a variety of motivations for quantifying Pu in spent (used) fuel assemblies by means of nondestructive assay (NDA) including the following: strengthen the capabilities of the International Atomic Energy Agencies to safeguards nuclear facilities, quantifying shipper/receiver difference, determining the input accountability value at reprocessing facilities and providing quantitative input to burnup credit determination for repositories. For the purpose of determining the Pu mass in spent fuel assemblies, twelve NDA techniques were identified that provide information about the composition of an assembly. A key point motivating the present research path is the realization that none of these techniques, in isolation, is capable of both (1) quantifying the elemental Pu mass of an assembly and (2) detecting the diversion of a significant number of pins. As such, the focus of this work is determining how to best integrate 2 or 3 techniques into a system that can quantify elemental Pu and to assess how well this system can detect material diversion. Furthermore, it is important economically to down-select among the various techniques before advancing to the experimental phase. In order to achieve this dual goal of integration and down-selection, a Monte Carlo library of PWR assemblies was created and is described in another paper at Global 2009 (Fensin et al.). The research presented here emphasizes integration among techniques. An overview of a five year research plan starting in 2009 is given. Preliminary modeling results for the Monte Carlo assembly library are presented for 3 NDA techniques: Delayed Neutrons, Differential Die-Away, and Nuclear Resonance Fluorescence. As part of the focus on integration, the concept of"Pu isotopic correlation" is discussed and the role of cooling time determination.

Tobin, S. J.; Fensin, M. L.; Ludewigt, B. A.; Menlove, H. O.; Quiter, B. J.; Sandoval, N. P.; Swinhoe, M. T.; Thompson, S. J.

2009-08-03T23:59:59.000Z

416

Carbon and Nitrogen Dynamics in Agricultural Soils  

E-Print Network (OSTI)

Carbon and Nitrogen Dynamics in Agricultural Soils Model Applications at Different Scales in Time Print: SLU Service/Repro, Uppsala 2012 #12;Carbon and Nitrogen Dynamics in Agricultural Soils. Model Applications at Different Scales in Time and Space Abstract An understanding of soil organic carbon (C

417

Carbon sequestration by patch fertilization: A comprehensive assessment using coupled physical-ecological-biogeochemical models: FINAL REPORT of grant Grant No. DE-FG02-04ER63726  

SciTech Connect

This final report summarizes research undertaken collaboratively between Princeton University, the NOAA Geophysical Fluid Dynamics Laboratory on the Princeton University campus, the State University of New York at Stony Brook, and the University of California, Los Angeles between September 1, 2000, and November 30, 2006, to do fundamental research on ocean iron fertilization as a means to enhance the net oceanic uptake of CO2 from the atmosphere. The approach we proposed was to develop and apply a suite of coupled physical-ecologicalbiogeochemical models in order to (i) determine to what extent enhanced carbon fixation from iron fertilization will lead to an increase in the oceanic uptake of atmospheric CO2 and how long this carbon will remain sequestered (efficiency), and (ii) examine the changes in ocean ecology and natural biogeochemical cycles resulting from iron fertilization (consequences). The award was funded in two separate three-year installments: • September 1, 2000 to November 30, 2003, for a project entitled “Ocean carbon sequestration by fertilization: An integrated biogeochemical assessment.” A final report was submitted for this at the end of 2003 and is included here as Appendix 1. • December 1, 2003 to November 30, 2006, for a follow-on project under the same grant number entitled “Carbon sequestration by patch fertilization: A comprehensive assessment using coupled physical-ecological-biogeochemical models.” This report focuses primarily on the progress we made during the second period of funding subsequent to the work reported on in Appendix 1. When we began this project, we were thinking almost exclusively in terms of long-term fertilization over large regions of the ocean such as the Southern Ocean, with much of our focus being on how ocean circulation and biogeochemical cycling would interact to control the response to a given fertilization scenario. Our research on these types of scenarios, which was carried out largely during the first three years of our project, led to several major new insights on the interaction between ocean biogeochemistry and circulation. This work, which is described in 2 the following Section II on “Large scale fertilization,” has continued to appear in the literature over the past few years, including two high visibility papers in Nature. Early on in the first three years of our project, it became clear that small "patch-scale" fertilizations over limited regions of order 100 km diameter were much more likely than large scale fertilization, and we carried out a series of idealized patch fertilization simulations reported on in Gnanadesikan et al. (2003). Based on this paper and other results we had obtained by the end of our first three-year grant, we identified a number of important issues that needed to be addressed in the second three-year period of this grant. Section III on “patch fertilization” discusses the major findings of this phase of our research, which is described in two major manuscripts that will be submitted for publication in the near future. This research makes use of new more realistic ocean ecosystem and iron cycling models than our first paper on this topic. We have several major new insights into what controls the efficiency of iron fertilization in the ocean. Section IV on “model development” summarizes a set of papers describing the progress that we made on improving the ecosystem models we use for our iron fertilization simulations.

Sarmiento, Jorge L; Gnanadesikan, Anand; Gruber, Nicolas

2007-06-21T23:59:59.000Z

418

Carbon Nanotubes  

Science Conference Proceedings (OSTI)

Carbon Nanotubes. Sponsored by: TMS Electronic, Magnetic and Photonic Materials Division Date and Time: Sunday, February 13, 2005 ~ 8:30 am-5:00 pm

419

Carbon Nanomaterials  

Science Conference Proceedings (OSTI)

Mar 12, 2012 ... The graphene film was spin-coated using carbon nanotubes to form the cathode of the field emission device. A phosphor coated graphene-PET ...

420

Report on efforts to model and replicate the paths of the CarbonExplorers deployed April 2001 (NOAA GC04-304 (James Bishop, PI)  

Science Conference Proceedings (OSTI)

This report is intended to document the efforts I made tomodel the North Pacific in order to understand the path of the CarbonExplorers, deployed April 10, 2001. Interestingly, these floats movedwestward and northward in the first two months after deployment at OceanStation PAPA (hereafter, OSP), rather than eastward as expected. Myintent was to force the model with the observed winds and temperatures inorder to replicate the path of the floats during this time period. I thenwanted to compare these paths with the conditions in 2003, when thefloats took a more accelerated path and saw different biomass signatures.Unfortunately, I was never able to replicate the path of the 2001 floats:the model floats always went eastward. So, this report is a documentationof what I tried, some thoughts about why I was not successful, and afinal section explaining where the files are located at NERSC, in casesomeone else wants to expand on the current work.

Henning, Cara

2006-01-15T23:59:59.000Z

Note: This page contains sample records for the topic "determination modeling carbon" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


421

DEVELOPMENT OF A VALIDATED MODEL FOR USE IN MINIMIZING NOx EMISSIONS AND MAXIMIZING CARBON UTILIZATION WHEN CO-FIRING BIOMASS WITH COAL  

DOE Green Energy (OSTI)

This is the ninth Quarterly Technical Report for DOE Cooperative Agreement No. DE-FC26-00NT40895. A statement of the project objectives is included in the Introduction of this report. The pilot-scale testing phase of the project has been completed. Calculations are essentially completed for implementing a modeling approach to combine reaction times and temperature distributions from computational fluid dynamic models of the pilot-scale combustion furnace with char burnout and chemical reaction kinetics to predict NO{sub x} emissions and unburned carbon levels in the furnace exhaust. The REI Configurable Fireside Simulator (CFS) has proven to be an essential component to provide input for these calculations. Niksa Energy Associates expects to deliver their final report in February 2003. Work has continued on the project final report.

Larry G. Felix; P. Vann Bush

2003-01-29T23:59:59.000Z

422

Solubility of carbon in nanocrystalline ?-iron  

Science Conference Proceedings (OSTI)

A thermodynamic model for nanocrystalline interstitial alloys is presented. The equilibrium solid solubility of carbon in ?-iron is calculated for given grain size. Inside the strained nanograins local variation of the carbon content is predicted. ...

Alexander Kirchner; Bernd Kieback

2012-01-01T23:59:59.000Z

423

Modeling the effects of topography and wind on atmospheric dispersion of CO2 surface leakage at geologic carbon sequestration sites  

E-Print Network (OSTI)

model to model dense gas dispersion of CO 2 leakage. Themodified to simulate dense gas dispersion appropriate for CO3. Passive vs. dense gas dispersion The behavior of dense

Chow, Fotini K.

2009-01-01T23:59:59.000Z

424

Using Analytical and Numerical Modeling to Assess the Utility of Groundwater Monitoring Parameters at Carbon Capture, Utilization, and Storage Sites  

E-Print Network (OSTI)

://www.gettysburg.edu/academics/physics/clea/CLEAhome.html 4) Inner solar system orbital model http://donald.phast

Texas at Austin, University of

425

OPTIMIZATION OF THE CATHODE LONG-TERM STABILITY IN MOLTEN CARBONATE FUEL CELLS: EXPERIMENTAL STUDY AND MATHEMATICAL MODELING  

DOE Green Energy (OSTI)

SS 304 was encapsulated with thin layers of Co-Ni by an electroless deposition process. The corrosion behavior of SS304 and Co-Ni-SS304 was investigated in molten carbonate under cathode gas atmosphere with electrochemical and surface characterization tools. Surface modification of SS304 reduced the dissolution of chromium and nickel into the molten carbonate melt. Composition of the corrosion scale formed in case of Co-Ni-SS304 is different from SS304 and shows the presence of Co and Ni oxides while the latter shows the presence of lithium ferrite. Polarization resistance for oxygen reduction reaction and conductivity of corrosion values for the corrosion scales were obtained using impedance analysis and current-potential plots. The results indicated lower polarization resistance for oxygen reduction reaction in the case of Co-Ni-SS304 when compared to SS304. Also, the conductivity of the corrosion scales was considerably higher in case of Co-Ni-SS304 than the SS304. This study shows that modifying the current collector surface with Co-Ni coatings leads to the formation of oxide scales with improved barrier properties and electronic conductivity.

Dr. Ralph E. White

2001-03-31T23:59:59.000Z

426

NETL: Carbon Storage - Carbon Sequestration Leadership Forum  

NLE Websites -- All DOE Office Websites (Extended Search)

CSLF Carbon Storage Carbon Sequestration Leadership Forum CSLF Logo The Carbon Sequestration Leadership Forum (CSLF) is a voluntary climate initiative of industrially developed and...

427

Categorical Exclusion Determinations: B3.1 | Department of Energy  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

December 11, 2009 December 11, 2009 CX-000418: Categorical Exclusion Determination Characterization of the Triassic Newark Basin of New York and New Jersey for Geologic Storage of Carbon Dioxide CX(s) Applied: B3.1, A9 Date: 12/11/2009 Location(s): Poughkeepsie, New York Office(s): Fossil Energy, National Energy Technology Laboratory December 11, 2009 CX-002609: Categorical Exclusion Determination Modeling Carbon Dioxide Sequestration in Saline Aquifer and Depleted Oil Reservoir to Evaluate Regional Carbon Dioxide Sequestration Potential of Ozark Plateau Aquifer System, South-Central Kansas CX(s) Applied: B3.1, A9 Date: 12/11/2009 Location(s): Wichita, Kansas Office(s): Fossil Energy, National Energy Technology Laboratory December 11, 2009 CX-002610: Categorical Exclusion Determination

428

CX-004437: Categorical Exclusion Determination | Department of Energy  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

7: Categorical Exclusion Determination 7: Categorical Exclusion Determination CX-004437: Categorical Exclusion Determination Single-Well Low Temperature Carbon Dioxide-Based Engineered Geothermal System CX(s) Applied: A9, B3.1 Date: 11/16/2010 Location(s): Arizona Office(s): Energy Efficiency and Renewable Energy, Golden Field Office GreenFire Energy would use United States Department of Energy grant funds to identify and characterize the key uncertainties in the modeling and design of carbon dioxide-based Enhanced Geothermal Systems (EGS), then install a simplified prototype system to obtain the field data necessary for realistic cost and performance estimation of commercial scale carbon dioxide-EGS systems. Field portions of the project would occur on Arizona State Lands at the Saint Johns Dome formation near Springerville, Arizona.

429

CarbonSolve | Open Energy Information  

Open Energy Info (EERE)

CarbonSolve CarbonSolve Jump to: navigation, search Tool Summary LAUNCH TOOL Name: CarbonSolve Agency/Company /Organization: CarbonSolve Sector: Climate Focus Area: Greenhouse Gas Resource Type: Software/modeling tools User Interface: Website Website: www.carbonsolve.com Web Application Link: www.carbonsolve.com Cost: Paid CarbonSolve Screenshot References: CarbonSolve[1] Logo: CarbonSolve The CarbonSolve platform is designed to address a broad spectrum of needs, and makes possible for organizations to transform their sustainability objectives - including carbon, water, waste, employee engagement, or supply chain related initiatives into measureable metrics and trackable processes. Overview The CarbonSolve platform is designed to address a broad spectrum of needs, and makes possible for organizations to transform their sustainability

430

CX-003343: Categorical Exclusion Determination | Department of Energy  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

43: Categorical Exclusion Determination 43: Categorical Exclusion Determination CX-003343: Categorical Exclusion Determination Recovery Act: Experiment-Based Model for the Chemical Interactions between Geothermal Rocks, Supercritical Carbon Dioxide and Water CX(s) Applied: A9, B3.6 Date: 08/05/2010 Location(s): Palo Alto, California Office(s): Energy Efficiency and Renewable Energy, Golden Field Office Palo Alto Research Center, Incorporated (PARC) would design and develop a geochemical model that stimulates an Enhanced Geothermal System reservoir. The model would develop a foundation in theory and measurement of physical and chemical interactions between minerals, rocks, supercritical carbon dioxide, and water. The work would take place at the existing PARC facility located at 3333 Coyote Hill Road, Palo Alto, California 94304.

431

Carbon Footprinting for the Food Industry  

E-Print Network (OSTI)

174-1 Carbon Footprinting for the Food Industry Tim Bowser FAPC Food Process Engineer FAPC-174 and Natural Resources Carbon footprinting in the food industry is an activity that determines the greenhouse.g. tons) of carbon dioxide (CO2) equivalent per functional unit (e.g. kg or liter of goods sold) (PAS2050

Balasundaram, Balabhaskar "Baski"

432

OPTIMIZATION OF THE CATHODE LONG TERM STABILITY IN MOLTEN CARBONATE FUEL CELLS: EXPERIMENTAL STUDY AND MATHEMATICAL MODELING  

DOE Green Energy (OSTI)

The cathode materials for molten carbonate fuel cells (MCFCs) must have low dissolution rate, high structural strength and good electrical conductivity. Currently available cathodes are made of lithiated NiO which have acceptable structural strength and conductivity. However a study carried out by Orfeld et al. and Shores et al. indicated that the nickel cathodes dissolved, then precipitated and reformed as dendrites across the electrolyte matrix. This results in a decrease in cell utilization and eventually leads to shorting of the cell. The solubility of NiO was found to depend upon the acidity/basicity of the melt (basicity is directly proportional to log P{sub CO2}), carbonate composition, H{sub 2}O partial pressure and temperature. Urushibata et al. found that the dissolution of the cathode is a primary life limiting constraint of MCFCs, particularly in pressurized operation. With currently available NiO cathodes, the goal of 40,000 hours for the lifetime of MCFC appears achievable with cell operation at atmospheric pressure. However, the cell life at 10 atm and higher cell pressures is in the range between 5,000 to 10,000 hours. The overall objective of this research is to develop a superior cathode for MCFC's with improved catalytic ability, enhanced corrosion resistance with low ohmic losses, improved electronic conductivity. We also plan to understand the corrosion processes occurring at the cathode/molten carbonate interface. The following cathode materials will be subjected to detailed electrochemical, performance, structural and corrosion studies. (i) Passivated NiO alloys using chemical treatment with yttrium ion implantation and anodic yttrium molybdate treatment; (ii) Novel composite materials based on NiO and nanosized Ce, Yt, Mo; (iii) Co doped LiNiO{sub 2} LiNiO{sub 2} doped with 10 to 20% Co (LiCo{sub 0.2}NiO{sub 2}) and NiO cathodes; and (iv) CoO as a replacement for NiO. Passivation treatments will inhibit corrosion and increase the stability of the cathode at high temperatures. Deposition of refractory metals (Mo, W, Li{sub 2}NiCrO{sub 4}) will impart stability to the cathode at high temperatures. Further it will also increase the electrocatalytic activity and corrosion resistance of the cathode. Doping with Co will decrease the alloy dissolution and increase the cycle life of the cathode. In the reporting period the oxidation behavior of Ni and Co in Li + Na carbonate eutectic was investigated under oxidizing environment using cyclic voltammetry, electrochemical impedance spectroscopy and potentiodynamic technique. The open circuit potential was monitored as a function of time in order to evaluate the material's reactivity in the melt.

Anand Durairajan; Bala Haran; Branko N. Popov; Ralph E. White

2000-05-01T23:59:59.000Z

433

The adsorption effect of C{sub 6}H{sub 5} on density of states for double wall carbon nanotubes by tight binding model  

SciTech Connect

A theoretical approach based on a tight-binding model is developed to study the effects of the adsorption of finite concentrations of C{sub 6}H{sub 5} gas molecules on double-walled carbon nanotube (DWCNT) electronic properties. To obtain proper hopping integrals and random on-site energies for the case of one molecule adsorption, the local density of states for various hopping integrals and random on-site energies are calculated. Since C{sub 6}H{sub 5} molecule is a donor with respect to the carbon nanotubes and their states should appear near the conduction band of the system, effects of various hopping integral deviations and on-site energies for one molecule adsorption are considered to find proper hopping and on-site energies consistent with expected n-type semiconductor. We found that adsorption of C{sub 6}H{sub 5} gas molecules could lead to a (8.0)-(20.0) DWCNT n-type semiconductor. The width of impurity adsorbed gas states in the density of states could be controlled by adsorbed gas concentration.

Fathalian, A., E-mail: a.fathalian@gmail.com [Razi University, Department of Physics (Iran, Islamic Republic of)

2012-06-15T23:59:59.000Z

434

Incorporation of crop phenology in Simple Biosphere Model (SiBcrop) to improve land-atmosphere carbon exchanges from croplands  

E-Print Network (OSTI)

for integrated field crop management. Cornell Universityactivity within the crop canopy. Aust. J. agric. Res. , 23,Assessing uncertainties in crop model simulations using

Lokupitiya, Erandathie

2010-01-01T23:59:59.000Z

435

WTP Calculation Sheet: Determining the LAW Glass Former Constituents and Amounts for G2 and Acm Models. 24590-LAW-M4C-LFP-00002, Rev. B  

SciTech Connect

The purpose of this calculation is to determine the LAW glass former recipe and additives with their respective amounts. The methodology and equations contained herein are to be used in the G2 and ACM models until better information is supplied by R&T efforts. This revision includes calculations that determines the mass and volume of the bulk chemicals/minerals needed per batch. Plus, it contains calculations (for the G2 model) to help prevent overflow in LAW Feed Preparation Vessel.

Gimpel, Rodney F.; Kruger, Albert A.

2013-12-16T23:59:59.000Z

436

Determination of Basic Structure-Property Relations for Processing and Modeling in Advanced Nuclear Fuel: Microstructure Evolution and Mechanical Properties  

SciTech Connect

The project objective is to study structure-property relations in solid solutions of nitrides and oxides with surrogate elements to simulate the behavior of fuels of inert matrix fuels of interest to the Advanced Fuel Cycle Initiative (AFCI), with emphasis in zirconium-based materials. Work with actual fuels will be carried out in parallel in collaboration with Los Alamos National Laboratory (LANL). Three key aspects will be explored: microstructure characterization through measurement of global texture evolution and local crystallographic variations using Electron Backscattering Diffraction (EBSD); determination of mechanical properties, including fracture toughness, quasi-static compression strength, and hardness, as functions of load and temperature, and, finally, development of structure-property relations to describe mechanical behavior of the fuels based on experimental data. Materials tested will be characterized to identify the mechanisms of deformation and fracture and their relationship to microstructure and its evolution. New aspects of this research are the inclusion of crystallographic information into the evaluation of fuel performance and the incorporation of statistical variations of microstructural variables into simplified models of mechanical behavior of fuels that account explicitly for these variations. The work is expected to provide insight into processing conditions leading to better fuel performance and structural reliability during manufacturing and service, as well as providing a simplified testing model for future fuel production.

Kirk Wheeler; Manuel Parra; Pedro Peralta

2009-03-01T23:59:59.000Z

437

Determining Columbia and Snake River Project Tailrace and Forebay Zones of Hydraulic Influence using MASS2 Modeling  

SciTech Connect

Although fisheries biology studies are frequently performed at US Army Corps of Engineers (USACE) projects along the Columbia and Snake Rivers, there is currently no consistent definition of the ``forebay'' and ``tailrace'' regions for these studies. At this time, each study may use somewhat arbitrary lines (e.g., the Boat Restriction Zone) to define the upstream and downstream limits of the study, which may be significantly different at each project. Fisheries researchers are interested in establishing a consistent definition of project forebay and tailrace regions for the hydroelectric projects on the lower Columbia and Snake rivers. The Hydraulic Extent of a project was defined by USACE (Brad Eppard, USACE-CENWP) as follows: The river reach directly upstream (forebay) and downstream (tailrace) of a project that is influenced by the normal range of dam operations. Outside this reach, for a particular river discharge, changes in dam operations cannot be detected by hydraulic measurement. The purpose of this study was to, in consultation with USACE and regional representatives, develop and apply a consistent set of criteria for determining the hydraulic extent of each of the projects in the lower Columbia and Snake rivers. A 2D depth-averaged river model, MASS2, was applied to the Snake and Columbia Rivers. New computational meshes were developed most reaches and the underlying bathymetric data updated to the most current survey data. The computational meshes resolved each spillway bay and turbine unit at each project and extended from project to project. MASS2 was run for a range of total river flows and each flow for a range of project operations at each project. The modeled flow was analyzed to determine the range of velocity magnitude differences and the range of flow direction differences at each location in the computational mesh for each total river flow. Maps of the differences in flow direction and velocity magnitude were created. USACE fishery biologists requested data analysis to determine the project hydraulic extent based on the following criteria: 1) For areas where the mean velocities are less than 4 ft/s, the water velocity differences between operations are not greater than 0.5 ft/sec and /or the differences in water flow direction are not greater than 10 degrees, 2) If mean water velocity is 4.0 ft/second or greater the boundary is determined using the differences in water flow direction (i.e., not greater than 10 degrees). Based on these criteria, and excluding areas with a mean velocity of less than 0.1 ft/s (within the error of the model), a final set of graphics were developed that included data from all flows and all operations. Although each hydroelectric project has a different physical setting, there were some common results. The downstream hydraulic extent tended to be greater than the hydraulic extent in the forebay. The hydraulic extent of the projects tended to be larger at the mid-range flows. At higher flows, the channel geometry tends to reduce the impact of project operations.

Rakowski, Cynthia L.; Serkowski, John A.; Richmond, Marshall C.; Perkins, William A.

2010-12-01T23:59:59.000Z

438

Carbon nanotube IR detectors (SV)  

SciTech Connect

Sandia National Laboratories (Sandia) and Lockheed Martin Corporation (LMC) collaborated to (1) evaluate the potential of carbon nanotubes as channels in infrared (IR) photodetectors; (2) assemble and characterize carbon nanotube electronic devices and measure the photocurrent generated when exposed to infrared light;(3) compare the performance of the carbon nanotube devices with that of traditional devices; and (4) develop and numerically implement models of electronic transport and opto-electronic behavior of carbon nanotube infrared detectors. This work established a new paradigm for photodetectors.

Leonard, F. L.

2012-03-01T23:59:59.000Z

439

Water-Use Efficiency of the Terrestrial Biosphere: A Model Analysis Focusing on Interactions between the Global Carbon and Water Cycles  

Science Conference Proceedings (OSTI)

Carbon and water cycles are intimately coupled in terrestrial ecosystems, and water-use efficiency (WUE; carbon gain at the expense of unit water loss) is one of the key parameters of ecohydrology and ecosystem management. In this study, the ...

Akihiko Ito; Motoko Inatomi

2012-04-01T23:59:59.000Z

440

Determining Plutonium Mass in Spent Fuel with Nondestructive Assay Techniques -- Preliminary Modeling Results Emphasizing Integration among Techniques  

E-Print Network (OSTI)

LBNL- Determining Plutonium Mass in Spent Fuel withSwinhoe. “Determination of Plutonium Content in Spent FuelS. Tobin, “Measurement of Plutonium in Spent Nuclear Fuel by

Tobin, S. J.

2010-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "determination modeling carbon" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


441

CX-007107: Categorical Exclusion Determination | Department of...  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

CX-007107: Categorical Exclusion Determination Development of Novel Carbon Sorbents for Carbon Dioxide Capture CX(s) Applied: B3.6 Date: 10122011 Location(s): Toledo, Ohio...

442

CX-004238: Categorical Exclusion Determination | Department of...  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Categorical Exclusion Determination Carbon Dioxide-Water Emulsions for Enhanced Oil Recovery and Permanent Sequestration of Carbon Dioxide CX(s) Applied: A1, A9, A11 Date:...

443

Categorical Exclusion Determinations: National Energy Technology...  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Categorical Exclusion Determination Carbon Dioxide-Water Emulsions For Enhanced Oil Recovery And Permanent Sequestration Of Carbon Dioxide CX(s) Applied: A9, A11, B3.6...

444

Categorical Exclusion Determinations: American Recovery and Reinvestme...  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Categorical Exclusion Determination Carbon Dioxide-Water Emulsions for Enhanced Oil Recovery and Permanent Sequestration of Carbon Dioxide CX(s) Applied: A1, A9, A11 Date:...

445

An Analysis of Fuel Demand and Carbon Emissions in China  

E-Print Network (OSTI)

Under the Kyoto Protocol to the United Nations Framework Convention on Climate Change, targets have been set for various developed countries to reduce their carbon emissions. China's share of carbon emissions ranked the second highest in the world in 1996, only after the United States. Although China was not formally required to achieve a reduction in its carbon emissions under the protocol, pressures were mounting, especially from the United States, for China to address the issue seriously. Some recent research on China's carbon emissions has largely been carried out in the framework of computable general equilibrium models. For example, Fisher-Vanden (2003) used such models to assess the impact of market reforms on shaping the level and composition of carbon emissions; Garbaccio et al. (1999) and Zhang (1998) studied macroeconomic and sectoral effects of policies and instruments, such as, a carbon tax, on achieving predefined targets of carbon emissions. A common omission in these studies is the role of fuel price changes in determining the amount of carbon emissions. This paper first shows China's total CO2 emissions from burning all types of fossil fuels over the 50 years or so to 2001, with those from burning coal singled out for the purpose of illustrating coal as the major CO2 emitter. Then, using annual data for the period 1985-2000, the study investigates whether changes in the relative prices of various fuels reduce coal consumption. Four sectors in the Chinese economy are selected for the study, namely, the chemical industry, the metal industry, the non-metal materials industry and the residential sector, which are top energy as well as top coal consumers. Five fuels are considered, namely, coal, crude oil, electricity, natural gas and petroleum products, ...

Baiding Hu Department; Baiding Hu

2004-01-01T23:59:59.000Z

446

The Carbon Cycle  

NLE Websites -- All DOE Office Websites (Extended Search)

Carbon Cycle Print E-mail U.S. Carbon Cycle Science Program U.S. Carbon Cycle Science Program The U.S. Carbon Cycle Science Program, in consultation with the Carbon Cycle...

447

Determination of Thermodynamic Data for Modeling Corrosion: Volume 3: CO2-NaOH-H2O System  

Science Conference Proceedings (OSTI)

Preventing or diminishing corrosion in PWR steam generators requires an understanding of chemical reactions that occur at the metal-water interface. Tests performed with a high-temperature, corrosion-resistant flow calorimeter yielded important thermodynamic properties of several reactions involving potentially corrosive sodium ions and carbon dioxide.

1992-03-01T23:59:59.000Z

448

Carbon Sequestration  

NLE Websites -- All DOE Office Websites (Extended Search)

David a. Lang David a. Lang Project Manager National Energy Technology Laboratory 626 Cochrans Mill Road P.O. Box 10940 Pittsburgh, PA 15236 412-386-4881 david.lang@netl.doe.gov andrew chizmeshya Arizona State University Center for Solid State Science Tempe, AZ 85287-1704 480-965-6072 chizmesh@asu.edu A Novel ApproAch to MiNerAl cArboNAtioN: eNhANciNg cArboNAtioN While AvoidiNg MiNerAl pretreAtMeNt process cost Background Carbonation of the widely occurring minerals of the olivine group, such as forsterite (Mg 2 SiO 4 ), is a potential large-scale sequestration process that converts CO 2 into the environmentally benign mineral magnesite (MgCO 3 ). Because the process is exothermic, it inherently offers low-cost potential. Enhancing carbonation reactivity is the key to economic viability. Previous

449

Biogeochemistry of Carbon in the Amazonian Floodplains over a 2000-km Reach: Insights from a Process-Based Model  

Science Conference Proceedings (OSTI)

The influence of Amazonian floodplains on the hydrological, sedimentary, and biogeochemical river budget was investigated over a 2000-km reach. A process-based model relying on the closure of chemical fluxes and isotopic signals was implemented. ...

Vincent Bustillo; Reynaldo Luiz Victoria; Jose Mauro Sousa de Moura; Daniel de Castro Victoria; Andre Marcondes Andrade Toledo; Erich Colicchio

2011-01-01T23:59:59.000Z

450

Response of a Coupled Ocean–Atmosphere Model to Increasing Atmospheric Carbon Dioxide: Sensitivity to the Rate of Increase  

Science Conference Proceedings (OSTI)

The influence of differing rates of increase of the atmospheric CO2 concentration on the climatic response is investigated using a coupled ocean–atmosphere model. Five transient integrations are performed each using a different constant ...

Ronald J. Stouffer; Syukuro Manabe

1999-08-01T23:59:59.000Z

451

DEVELOPMENT OF A VALIDATED MODEL FOR USE IN MINIMIZING NOx EMISSIONS AND MAXIMIZING CARBON UTILIZATION WHEN CO-FIRING BIOMASS WITH COAL  

DOE Green Energy (OSTI)

This is the eighth Quarterly Technical Report for DOE Cooperative Agreement No. DE-FC26-00NT40895. A statement of the project objectives is included in the Introduction of this report. The final biomass co-firing test burn was conducted during this quarter. In this test (Test 14), up to 20% by weight dry switchgrass was comilled with Jim Walters No.7 mine coal and injected through the single-register burner. Jim Walters No.7 coal is a low-volatility, low-sulfur ({approx}0.7% S) Eastern bituminous coal. The results of this test are presented in this quarterly report. Progress has continued to be made in implementing a modeling approach to combine reaction times and temperature distributions from computational fluid dynamic models of the pilot-scale combustion furnace with char burnout and chemical reaction kinetics to predict NO{sub x} emissions and unburned carbon levels in the furnace exhaust. The REI Configurable Fireside Simulator (CFS) is now in regular use. Presently, the CFS is being used to generate CFD calculations for completed tests with Powder River Basin coal and low-volatility (Jim Walters No.7 Mine) coal. Niksa Energy Associates will use the results of these CFD simulations to complete their validation of the NOx/LOI predictive model. Work has started on the project final report.

Larry G. Felix; P. Vann Bush

2002-10-26T23:59:59.000Z

452

Building A Simulation Model For The Prediction Of Temperature Distribution In Pulsed Laser Spot Welding Of Dissimilar Low Carbon Steel 1020 To Aluminum Alloy 6061  

Science Conference Proceedings (OSTI)

This paper describes the development of a computer model used to analyze the heat flow during pulsed Nd: YAG laser spot welding of dissimilar metal; low carbon steel (1020) to aluminum alloy (6061). The model is built using ANSYS FLUENT 3.6 software where almost all the environments simulated to be similar to the experimental environments. A simulation analysis was implemented based on conduction heat transfer out of the key hole where no melting occurs. The effect of laser power and pulse duration was studied.Three peak powers 1, 1.66 and 2.5 kW were varied during pulsed laser spot welding (keeping the energy constant), also the effect of two pulse durations 4 and 8 ms (with constant peak power), on the transient temperature distribution and weld pool dimension were predicated using the present simulation. It was found that the present simulation model can give an indication for choosing the suitable laser parameters (i.e. pulse durations, peak power and interaction time required) during pulsed laser spot welding of dissimilar metals.

Yousef, Adel K. M. [Faculty of Engineering , University of Diyala, Diyala-Baqouba (Iraq); Taha, Ziad A.; Shehab, Abeer A. [Institute of laser for postgraduate studies, Baghdad University, Baghdad (Iraq)

2011-01-17T23:59:59.000Z

453

DEVELOPMENT OF A VALIDATED MODEL FOR USE IN MINIMIZING NOx EMISSIONS AND MAXIMIZING CARBON UTILIZATION WHEN CO-FIRING BIOMASS WITH COAL  

SciTech Connect

This is the third Quarterly Technical Report for DOE Cooperative Agreement No. DE-FC26-00NT40895. A statement of the project objectives is included in the Introduction of this report. Three additional biomass co-firing test burns have been conducted. In the first test (Test 3), up to 20% by weight dry hardwood sawdust and dry switchgrass was injected through the center of the burner. In the second test (Test 4), 100% Pratt seam coal was burned in a repeat of the initial test condition of Test 1, to reconcile irregularities in the data from the first test. In the third test (Test 5), up to 20% by weight dry hardwood sawdust and dry switchgrass was injected through an external pipe directed toward the exit of the burner. Progress has continued in developing a modeling approach to synthesize the reaction time and temperature distributions that will be produced by computational fluid dynamic models of the pilot-scale combustion furnace and the char burnout and chemical reaction kinetics that will predict NOx emissions and unburned carbon levels in the furnace exhaust. Additional results of CFD modeling efforts have been received and Preparations are under way for continued pilot-scale combustion experiments. Finally, a presentation was made at a Biomass Cofiring Project Review Meeting held at the NETL in Pittsburgh, PA on June 20-21.

Larry G. Felix; P. Vann Bush

2001-07-17T23:59:59.000Z

454

DEVELOPMENT OF A VALIDATED MODEL FOR USE IN MINIMIZING NOx EMISSIONS AND MAXIMIZING CARBON UTILIZATION WHEN CO-FIRING BIOMASS WITH COAL  

DOE Green Energy (OSTI)

In full-scale boilers, the effect of biomass cofiring on NO{sub x} and unburned carbon (UBC) emissions has been found to be site-specific. Few sets of field data are comparable and no consistent database of information exists upon which cofiring fuel choice or injection system design can be based to assure that NOX emissions will be minimized and UBC be reduced. This report presents the results of a comprehensive project that generated an extensive set of pilot-scale test data that were used to validate a new predictive model for the cofiring of biomass and coal. All testing was performed at the 3.6 MMBtu/hr (1.75 MW{sub t}) Southern Company Services/Southern Research Institute Combustion Research Facility where a variety of burner configurations, coals, biomasses, and biomass injection schemes were utilized to generate a database of consistent, scalable, experimental results (422 separate test conditions). This database was then used to validate a new model for predicting NO{sub x} and UBC emissions from the cofiring of biomass and coal. This model is based on an Advanced Post-Processing (APP) technique that generates an equivalent network of idealized reactor elements from a conventional CFD simulation. The APP reactor network is a computational environment that allows for the incorporation of all relevant chemical reaction mechanisms and provides a new tool to quantify NOx and UBC emissions for any cofired combination of coal and biomass.

Larry G. Felix; P. Vann Bush; Stephen Niksa

2003-04-30T23:59:59.000Z

455

DEVELOPMENT OF A VALIDATED MODEL FOR USE IN MINIMIZING NOx EMISSIONS AND MAXIMIZING CARBON UTILIZATION WHEN CO-FIRING BIOMASS WITH COAL  

DOE Green Energy (OSTI)

This is the fifth Quarterly Technical Report for DOE Cooperative Agreement No. DE-FC26-00NT40895. A statement of the project objectives is included in the Introduction of this report. One additional biomass co-firing test burn was conducted during this quarter. In this test (Test 9), up to 20% by weight dry hardwood sawdust and switchgrass was injected through the center of the single-register burner with Jacobs Ranch coal. Jacobs Ranch coal is a low-sulfur Powder River Basin coal ({approx} 0.5% S). The results from Test 9 as well as for Test 8 (conducted late last quarter) are presented in this quarterly report. Significant progress has been made in implementing a modeling approach to combine reaction times and temperature distributions from computational fluid dynamic models of the pilot-scale combustion furnace with char burnout and chemical reaction kinetics to predict NO{sub x} emissions and unburned carbon levels in the furnace exhaust. Additional results of CFD modeling efforts have been received and preparations are under way for continued pilot-scale combustion experiments with the dual-register burner. Finally, a project review was held at NETL in Pittsburgh, on November 13, 2001.

Larry G. Felix; P. Vann Bush

2002-01-31T23:59:59.000Z

456

DEVELOPMENT OF A VALIDATED MODEL FOR USE IN MINIMIZING NOx EMISSIONS AND MAXIMIZING CARBON UTILIZATION WHEN CO-FIRING BIOMASS WITH COAL  

DOE Green Energy (OSTI)

This is the second Quarterly Technical Report for DOE Cooperative Agreement No. DE-FC26-00NT40895. A statement of the project objectives is included in the Introduction of this report. Two biomass co-firing test burns have been conducted. In the first test, up to 20% by weight dry hardwood sawdust and dry switchgrass was co-milled Pratt seam coal. In the second test, also with Pratt seam coal, up to 10% by weight dry hardwood sawdust was injected through the center of the burner. Progress has continued in developing a modeling approach to synthesize the reaction time and temperature distributions that will be produced by computational fluid dynamic models of the pilot-scale combustion furnace and the char burnout and chemical reaction kinetics that will predict NOx emissions and unburned carbon levels in the furnace exhaust. Preliminary results of CFD modeling efforts have been received and Preparations are under way for continued pilot-scale combustion experiments.

Larry G. Felix; P. Vann Bush

2001-04-30T23:59:59.000Z

457

Three Dimensional CFD Model of a Planar Solid Oxide Electrolysis Cell for Co-Electrolysis of Steam and Carbon-Dioxide  

SciTech Connect

A three-dimensional computational fluid dynamics (CFD) model has been created to model high temperature co-electrolysis of steam and carbon dioxide in a planar solid oxide electrolyzer (SOE). A research program is under way at the Idaho National Laboratory (INL) to simultaneously address the research and scale-up issues associated with the implementation of planar solid-oxide electrolysis cell technology for syn-gas production from CO2 and steam. Various runs have been performed under different run conditions to help assess the performance of the SOE. An experimental study is also being performed at the INL to assess the SOE. Model results provide detailed profiles of temperature, Nernst potential, operating potential, anode-side gas composition, cathode-side gas composition, current density and syn-gas production over a range of stack operating conditions. Typical results of current density versus cell potential, cell current versus H2 and CO production, temperature, and voltage potential are all presented within this paper. Plots of mole fraction of CO2, CO, H2, H2O, O2, are presented. Currently there is strong interest in the large-scale production of syn-gas from CO2 and steam to be reformed into a usable transportation fuel. This process takes the carbon-neutral approach where the amount of CO2 in the atmosphere does not increase. Consequently, there is a high level of interest in production of syn-gas from CO2 and steam electrolysis. Worldwide, the demand for light hydrocarbon fuels like gasoline and diesel oil is increasing. To satisfy this demand, oil companies have begun to utilize oil deposits of lower hydrogen. In the mean time, with the price of oil currently over $70 / barrel, synthetically-derived hydrocarbon fuels (synfuels) have become economical. Synfuels are typically produced from syngas – hydrogen (H2) and carbon monoxide (CO) -- using the Fischer-Tropsch process, discovered by Germany before World War II. South Africa has used synfuels to power a significant number of their buses, trucks, and taxicabs. The Idaho National Laboratory (INL), in conjunction with Ceramatec Inc. (Salt Lake City, USA) has been researching for several years the use of solid-oxide fuel cell technology to electrolyze steam for large-scale nuclear-powered hydrogen production. Now, an experimental research project is underway at the INL to investigate the feasibility of producing syngas by simultaneously electrolyzing at high-temperature steam and carbon dioxide (CO2) using solid oxide fuel cell technology. High-temperature nuclear reactors have the potential for substantially increasing the efficiency of syn-gas production from CO2 and water, with no consumption of fossil fuels, and no production of greenhouse gases. Thermal CO2-splitting and water splitting for syn-gas production can be accomplished via high-temperature electrolysis or thermochemical processes, using high-temperature nuclear process heat. In order to achieve competitive efficiencies, both processes require high-temperature operation (~850°C). High-temperature electrolytic CO2 and water splitting supported by nuclear process heat and electricity has the potential to produce syn-gas with an overall system efficiency near those of the thermochemical processes. Specifically, a high-temperature advanced nuclear reactor coupled with a high-efficiency high-temperature electrolyzer could achieve a competitive thermal-to-syn-gas conversion efficiency of 45 to

G. Hawkes; J. O' Brien; C. Stoots; S. Herring; R. Jones

2006-11-01T23:59:59.000Z