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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

Solubility of carbon dioxide in tar sand bitumen; Experimental determination and modeling  

SciTech Connect (OSTI)

This paper reports on an understanding of the solubility of carbon dioxide (CO{sub 2}) in tar sand bitumen that is essential for the development of in situ processes in the recovery of bitumen from tar and deposits. The solubility of CO{sub 2} in the Tar Sand Triangle (Utah), the PR Spring Rainbow I (Utah), and the Athabasca (Canada) tar sand bitumens was determined with the use of a high-pressure microbalance at temperatures of 358.2 and 393.2 K and pressures up to 6.2 MPa. As expected, the solubilities increased with pressure at a given temperature and decreased with increases in temperature. The Peng--Robinson and the Schmidt--Wenzel equations of state were used to match the experimentally observed solubilities. Correlations for the interaction parameters between CO{sub 2} and the bitumen were developed for both equations of state, wherein the interaction parameter could be obtained by using specific gravity and the UOP {ital K} factor for the bitumen. The correlations were developed with the optimum interaction parameters obtained for each of the samples at each temperature.

Deo, M.D.; Wang, C.J.; Hanson, F.V. (Dept. of Fuels Engineering, Univ. of Utah, Salt Lake City, UT (US))

1991-03-01T23:59:59.000Z

2

RELATIVE CHIRAL ABUNDANCES OF CARBON NANOTUBES DETERMINED BYRELATIVE CHIRAL ABUNDANCES OF CARBON NANOTUBES DETERMINED BYRELATIVE CHIRAL ABUNDANCES OF CARBON NANOTUBES DETERMINED BYRELATIVE CHIRAL ABUNDANCES OF CARBON NANOTUBES DETERMINED BY RESONANT RAMAN  

E-Print Network [OSTI]

RELATIVE CHIRAL ABUNDANCES OF CARBON NANOTUBES DETERMINED BYRELATIVE CHIRAL ABUNDANCES OF CARBON NANOTUBES DETERMINED BYRELATIVE CHIRAL ABUNDANCES OF CARBON NANOTUBES DETERMINED BYRELATIVE CHIRAL ABUNDANCES OF CARBON NANOTUBES DETERMINED BY RESONANT RAMAN SPECTROSCOPY USING A TUNABLE DYE LASERRESONANT

Mellor-Crummey, John

3

Use of molecular modeling to determine the interaction and competition of gases within coal for carbon dioxide sequestration  

SciTech Connect (OSTI)

Molecular modeling was employed to both visualize and probe our understanding of carbon dioxide sequestration within a bituminous coal. A large-scale (>20,000 atoms) 3D molecular representation of Pocahontas No. 3 coal was generated. This model was constructed based on a the review data of Stock and Muntean, oxidation and decarboxylation data for aromatic clustersize frequency of Stock and Obeng, and the combination of Laser Desorption Mass Spectrometry data with HRTEM, enabled the inclusion of a molecular weight distribution. The model contains 21,931 atoms, with a molecular mass of 174,873 amu, and an average molecular weight of 714 amu, with 201 structural components. The structure was evaluated based on several characteristics to ensure a reasonable constitution (chemical and physical representation). The helium density of Pocahontas No. 3 coal is 1.34 g/cm{sup 3} (dmmf) and the model was 1.27 g/cm{sup 3}. The structure is microporous, with a pore volume comprising 34% of the volume as expected for a coal of this rank. The representation was used to visualize CO{sub 2}, and CH{sub 4} capacity, and the role of moisture in swelling and CO{sub 2}, and CH{sub 4} capacity reduction. Inclusion of 0.68% moisture by mass (ash-free) enabled the model to swell by 1.2% (volume). Inclusion of CO{sub 2} enabled volumetric swelling of 4%.

Jeffrey D. Evanseck; Jeffry D. Madura; Jonathan P. Mathews

2006-04-21T23:59:59.000Z

4

4, 1367, 2007 Modelling carbon  

E-Print Network [OSTI]

BGD 4, 13­67, 2007 Modelling carbon overconsumption and extracellular POC formation M. Schartau et carbon overconsumption and the formation of extracellular particulate organic carbon M. Schartau1 , A Correspondence to: M. Schartau (markus.schartau@gkss.de) 13 #12;BGD 4, 13­67, 2007 Modelling carbon

Paris-Sud XI, Université de

5

Carbon Mineralizability Determines Interactive Effects onMineralizatio...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Determines Interactive Effects onMineralization of Pyrogenic Organic Matter and Soil Organic Carbon. Carbon Mineralizability Determines Interactive Effects onMineralization...

6

Simple ocean carbon cycle models  

SciTech Connect (OSTI)

Simple ocean carbon cycle models can be used to calculate the rate at which the oceans are likely to absorb CO{sub 2} from the atmosphere. For problems involving steady-state ocean circulation, well calibrated ocean models produce results that are very similar to results obtained using general circulation models. Hence, simple ocean carbon cycle models may be appropriate for use in studies in which the time or expense of running large scale general circulation models would be prohibitive. Simple ocean models have the advantage of being based on a small number of explicit assumptions. The simplicity of these ocean models facilitates the understanding of model results.

Caldeira, K. [Lawrence Livermore National Lab., CA (United States); Hoffert, M.I. [New York Univ., NY (United States). Dept. of Earth System Sciences; Siegenthaler, U. [Bern Univ. (Switzerland). Inst. fuer Physik

1994-02-01T23:59:59.000Z

7

Determination of the atherogenic potential of inhaled carbon monoxide  

SciTech Connect (OSTI)

he effects of chronic exposure to moderate levels of carbon monoxide upon the augmentation of arteriosclerotic plaque development were investigated in a series of in vivo studies in the cockerel (young rooster). This animal model has been well characterized, especially regarding the role of environmental agents in exacerbating early stages of plaque development. Cockerels injected with subtumorigenic doses of carcinogens exhibit markedly accelerated development of aortic arteriosclerotic plaques. Inhalation of mainstream smoke from two packs of cigarettes (100 minutes/day for 16 weeks) causes small but statistically significant increases in plaque size. As is the case with many animal models of plaque development, raised fat-proliferative plaques also appear in these animals following cholesterol feeding. Carbon monoxide is a ubiquitous pollutant in urban environments, where it is derived largely from mobile sources and cigarette smoke. Exposure to chronically elevated carbon monoxide levels has been implicated in a number of health-related problems. Whether such exposure plays a role in the development of arteriosclerosis has not been determined conclusively. In the present study, three questions were posed: 1. Will inhaled carbon monoxide at levels of 50 to 200 parts per million (ppm)* (two hours/day for 16 weeks) be sufficient to augment arteriosclerotic plaque development in cockerels, in the absence of other plaque-promoting agents 2. Will the inhalation of 100 ppm carbon monoxide (two hours/day for 16 weeks), concomitant with the feeding of low levels (0.1%) of cholesterol, yield larger plaques than those obtained with either of these agents administered alone 3. Will inhalation of 100 ppm carbon monoxide (two hours/day for 11 or 22 weeks), by cockerels in whom plaques have already appeared, further augment plaque development Cockerels were exposed to carefully regulated levels of carbon monoxide in stainless-steel and Plexiglas dynamic exposure chambers.

Penn, A. (New York Univ. Medical Center, NY (United States))

1993-05-01T23:59:59.000Z

8

Low Cost Carbon Fiber Production Carbon Fiber Manufacturing Cost Modeling  

E-Print Network [OSTI]

to bond with composite matrix material. It is important that a carbon fiber manufacturing cost model manufactured with carbon fiber as opposed to traditional materials such as steel, automotive parts are able associated with both the manufacture of carbon fibers themselves as well as their composites. Traditional

9

Multiscale Modeling with Carbon Nanotubes  

SciTech Connect (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 such materials can range from equilibrium and nonequilibrium Quantum Mechanics, to force-field-based Molecular Mechanics and kinetic Monte Carlo, to Mesoscale simulation of evolving morphology, to Finite-Element computation of physical properties. This brief review illustrates some of the above modeling techniques through a number of recent applications with carbon nanotubes: nano electromechanical sensors (NEMS), chemical sensors, metal-nanotube contacts, and polymer-nanotube composites.

Maiti, A

2006-02-21T23:59:59.000Z

10

Determination of carbon, nitrogen, and oxygen in high purity magnesium  

E-Print Network [OSTI]

DETERMINATION OF CARBON, NITROGEN, AND OXYGEN IN HIGH PURITY MAGNESIUM A Thesis by NEIL GERARD ROCHE Submitted to the Graduate College of Texas A8cM University in partial i'ulfillment of the requirement for the degree of MASTER OF SCIENCE... December 1981 Major Subject: Chemistry DETERMINATION OF CARBON, NITROGEN, AND OXYGEN IN HIGH PURITY MAGNESIUM A Thesis by NEIL GERARD ROCHE Approved as to style and content by: E. A. Schweikert (Chairman of Committee) G. J. Bastiaans (Member) L...

Roche, Neil Gerard

2012-06-07T23:59:59.000Z

11

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

SciTech Connect (OSTI)

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

12

Determination of Organophosphate Pesticides at a Carbon  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmospheric Optical Depth7-1D: Vegetation Proposed Newcatalyst phasesData FilesShape, Density,TiO2(110). | EMSLDetermination

13

EB2012-MS-43 ADVANCES IN THE MODELLING OF CARBON/CARBON  

E-Print Network [OSTI]

, the Carbon-Carbon composites (C/C) are materials frequently used in industrial applications such as planeEB2012-MS-43 ADVANCES IN THE MODELLING OF CARBON/CARBON COMPOSITE UNDER TRIBOLOGICAL CONSTRAINTS 1, homogenization, carbon ABSTRACT Thermo mechanical properties of Carbon-Carbon composite (C/C) allow them

Paris-Sud XI, Université de

14

A new carbon-13 method for determining aromatic, naphthenic and paraffinic carbon  

SciTech Connect (OSTI)

The determination of the relative percentages of aromatic, naphthenic and paraffinic carbon in samples of natural origin is important for many petroleum related studies including processing, geological studies, and certain product specifications. The normal method is the n-d-M method which requires the measurement of refractive index, density and molecular weight and a ternary correlation diagram to obtain the relative carbon percentages. It is difficult or inconvenient to make n-d-M measurements of very heavy products and the presence of significant amounts of polar materials makes n-d-M results inaccurate. The average molecular parameters determinable by a number of NMR techniques are directly or indirectly related to the percentage of various carbon types present in the mixture. Unfortunately, all the standard techniques we have examined have some built-in assumption which does not allow the accurate calculation of relative carbon percentages. For example, any proton technique applicable to aromatic fractions will give potentially low values for naphthenic carbon because naphthenic carbon is normally determined from the ..beta..-CH/sub 2/ region of tetralin-type structures (1.65-1.9 ppm). This is a very specific kind of naphthenic structure and to the extent that more than one saturate ring is asymmetrically condensed to the aromatic ring or that the saturate rings are not directly condensed to the aromatic rings, the method will fail.

Galya, L.G.; Young, D.C.

1983-09-01T23:59:59.000Z

15

New Computer Model Pinpoints Prime Materials for Carbon Capture  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Model Pinpoints Prime Materials for Carbon Capture New Computer Model Pinpoints Prime Materials for Carbon Capture July 17, 2012 | Tags: Dirac, Energy Technologies, Materials...

16

Three phase carbon EOS model with electronic excitation  

SciTech Connect (OSTI)

A simple and rapid way for computing EOS data of multiphase solids with a liquid phase is described with emphasis on carbon. The method uses a scaling model for the liquid phase and includes a provision for electronic effects. The free energy minimum determines the stable phase.

van Thiel, M.; Ree, F.H.; Grover, R.

1987-07-01T23:59:59.000Z

17

Monitoring Forest Carbon Sequestration with Remote Sensing and Carbon Cycle Modeling  

E-Print Network [OSTI]

America, forest carbon sinks are be- lieved to offset a significant proportion of carbon emis- sionsMonitoring Forest Carbon Sequestration with Remote Sensing and Carbon Cycle Modeling DAVID P University Corvallis, Oregon 97331-5752, USA ABSTRACT / Sources and sinks of carbon associated with forests

Lefsky, Michael

18

Carbon Dioxide Corrosion: Modelling and Experimental Work  

E-Print Network [OSTI]

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

19

Effective models for excitons in carbon nanotubes  

E-Print Network [OSTI]

We analyse the low lying spectrum of a model of excitons in carbon nanotubes. Consider two particles with an attractive Coulomb self-interaction, placed on an infinitely long cylinder. If the cylinder radius becomes small, the low lying spectrum is well described by a one-dimensional effective Hamiltonian which is exactly solvable.

Horia D. Cornean; Pierre Duclos; Benjamin Ricaud

2006-05-04T23:59:59.000Z

20

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

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

Linking Numerical and Analytical Models of Carbon Leakage By Jared C. Carbone  

E-Print Network [OSTI]

Linking Numerical and Analytical Models of Carbon Leakage By Jared C. Carbone Carbon leakage describes the economy- wide response in carbon emission levels caused by abatement in one part efforts will be offset by emis- sion increases (a positive net leakage effect) elsewhere in the world

22

Modelling Correlation in Carbon and Energy Markets  

E-Print Network [OSTI]

prices are also used in optimization of power generation plant portfolios. Roques et al. (2008) use cross-correlations and standard deviations of UK quarter-ahead fuel, power and carbon prices in a Monte-Carlo simulation of power plant net present values... plant portfolio, which may contain nu- clear, gas and coal plants as well as generation from renewable sources such as wind and hydro. Relative marginal power generation costs determine which plant will serve to produce baseload electricity and which...

Koenig, Philipp

2011-02-10T23:59:59.000Z

23

Theoretical Model for Nanoporous Carbon Supercapacitors  

SciTech Connect (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 (< 2 nm pore size). Our analysis of the available experimental data in the micropore regime is confirmed by 1st principles density functional theory calculations and reveals significant curvature effects for carbon capacitance. The EDCC (and/or 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. 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

24

Systematic determination of absolute absorption cross-section of individual carbon nanotubes  

E-Print Network [OSTI]

Systematic determination of absolute absorption cross-section of individual carbon nanotubes Kaihui of optical contrast from individual carbon nanotubes has been successfully achieved with a polarization-sensitivity absorption spectros- copy for individual single-walled carbon nanotubes by combining the polarization

Wang, Feng

25

Estimation of Parameters in Carbon Sequestration Models from Net Ecosystem  

E-Print Network [OSTI]

Estimation of Parameters in Carbon Sequestration Models from Net Ecosystem Exchange Data Luther in the context of a deterministic com- partmental carbon sequestration system. Sensitivity and approximation usefulness in the estimation of parameters within a compartmental carbon sequestration model. Previously we

White, Luther

26

Economic Modeling of Carbon Capture and Sequestration Technologies  

E-Print Network [OSTI]

Economic Modeling of Carbon Capture and Sequestration Technologies Jim McFarland (jrm1@mit.edu; +1 explores the economics of carbon capture and sequestration technologies as applied to electric generating of the world economy, is used to model two of the most promising carbon capture and sequestration (CCS

27

Numerical simulation and modeling of carbon nanotubes.  

E-Print Network [OSTI]

??The discovery of carbon nanotubes has triggered a significant amount of interest. Since then, much research has been done on these new forms of carbon (more)

Wong, Chee How.

2008-01-01T23:59:59.000Z

28

Silicon Carbide Derived Carbons: Experiments and Modeling  

SciTech Connect (OSTI)

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

29

Modelling Heat Transfer of Carbon Nanotubes  

E-Print Network [OSTI]

Modelling heat transfer of carbon nanotubes is important for the thermal management of nanotube-based composites and nanoelectronic device. By using a finite element method for three-dimensional anisotropic heat transfer, we have simulated the heat conduction and temperature variations of a single nanotube, a nanotube array and a part of nanotube-based composite surface with heat generation. The thermal conductivity used is obtained from the upscaled value from the molecular simulations or experiments. Simulations show that nanotube arrays have unique cooling characteristics due to its anisotropic thermal conductivity.

Yang, Xin-She

2010-01-01T23:59:59.000Z

30

Ab Initio Thermodynamic Model for Magnesium Carbonates and Hydrates  

SciTech Connect (OSTI)

An ab initio thermodynamic framework for predicting properties of hydrated magnesium carbonate minerals has been developed using density-functional theory linked to macroscopic thermodynamics through the experimental chemical potentials for MgO, water, and CO2. Including semiempirical dispersion via the Grimme method and small corrections to the generalized gradient approximation of Perdew, Burke, and Ernzerhof for the heat of formation yields a model with quantitative agreement for the benchmark minerals brucite, magnesite, nesquehonite, and hydromagnesite. The model shows how small differences in experimental conditions determine whether nesquehonite, hydromagnesite, or magnesite is the result of laboratory synthesis from carbonation of brucite, and what transformations are expected to occur on geological time scales. Because of the reliance on parameter-free first principles methods, the model is reliably extensible to experimental conditions not readily accessible to experiment and to any mineral composition for which the structure is known or can be hypothesized, including structures containing defects, substitutions, or transitional structures during solid state transformations induced by temperature changes or processes such as water, CO2, or O2 diffusion. Demonstrated applications of the ab initio thermodynamic framework include an independent means to evaluate differences in thermodynamic data for lansfordite, predicting the properties of Mg analogs of Ca-based hydrated carbonates monohydrocalcite and ikaite which have not been observed in nature, and an estimation of the thermodynamics of barringtonite from the stoichiometry and a single experimental observation.

Chaka, Anne M.; Felmy, Andrew R.

2014-03-28T23:59:59.000Z

31

A model of carbon evasion and sedimentation in temperate lakes  

E-Print Network [OSTI]

A model of carbon evasion and sedimentation in temperate lakes PA U L C . H A N S O N *, A M I N., Madison, WI 53726, USA Abstract Lakes process terrigenous carbon. The carbon load processed by lakes may partially offset estimates made for terrestrial net ecosystem exchange (NEE). The balance within lakes

Turner, Monica G.

32

Validation of Material Models for Automotive Carbon Fiber Composite...  

Broader source: Energy.gov (indexed) [DOE]

Validation of Material Models for Automotive Carbon Fiber Composite Structures (VMM) Libby Berger (General Motors), Omar Faruque (Ford) Co-Principal Investigators US Automotive...

33

Determination of the Effect of Geological Reservoir Variability on Carbon Dioxide Storage  

E-Print Network [OSTI]

Determination of the Effect of Geological Reservoir Variability on Carbon Dioxide Storage Using'expriences -- Dans le contexte de l'tude du stockage gologique du dioxyde de carbone dans les rservoirs al. (2007) Energy Convers. Manage. 48, 1782-1797; Gunter et al. (1999) Appl. Geochem. 4, 1

Paris-Sud XI, Universit de

34

Random vs realistic amorphous carbon models for high resolution microscopy and electron diffraction  

SciTech Connect (OSTI)

Amorphous carbon and amorphous materials in general are of particular importance for high resolution electron microscopy, either for bulk materials, generally covered with an amorphous layer when prepared by ion milling techniques, or for nanoscale objects deposited on amorphous substrates. In order to quantify the information of the high resolution images at the atomic scale, a structural modeling of the sample is necessary prior to the calculation of the electron wave function propagation. It is thus essential to be able to reproduce the carbon structure as close as possible to the real one. The approach we propose here is to simulate a realistic carbon from an energetic model based on the tight-binding approximation in order to reproduce the important structural properties of amorphous carbon. At first, we compare this carbon with the carbon obtained by randomly generating the carbon atom positions. In both cases, we discuss the limit thickness of the phase object approximation. In a second step, we show the influence of both carbons models on (i) the contrast of Cu, Ag, and Au single atoms deposited on carbon and (ii) the determination of the long-range order parameter in CoPt bimetallic nanoalloys.

Ricolleau, C., E-mail: Christian.Ricolleau@univ-paris-diderot.fr; Alloyeau, D. [Laboratoire Matriaux et Phnomnes Quantiques, CNRS-UMR 7162, Universit Paris Diderot-Paris 7, Case 7021, 75205 Paris Cedex 13 (France); Le Bouar, Y.; Amara, H.; Landon-Cardinal, O. [Laboratoire d'Etude des Microstructures, UMR CNRS/Onera, 29, avenue de la Division Leclerc, 92322 Chtillon (France)

2013-12-07T23:59:59.000Z

35

CX-002611: Categorical Exclusion Determination | Department of...  

Broader source: Energy.gov (indexed) [DOE]

Exclusion Determination CX-002611: Categorical Exclusion Determination Modeling Carbon Dioxide Sequestration in Saline Aquifer and Depleted Oil Reservoir to Evaluate...

36

CX-000462: Categorical Exclusion Determination | Department of...  

Broader source: Energy.gov (indexed) [DOE]

Exclusion Determination CX-000462: Categorical Exclusion Determination Modeling Carbon Dioxide Sequestration in Saline Aquifer and Depleted Oil Reservoir to Evaluate...

37

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

Broader source: Energy.gov (indexed) [DOE]

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

38

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

Broader source: Energy.gov (indexed) [DOE]

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

39

Carbon Mineralizability Determines Interactive Effects onMineralization of  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmospheric Optical Depth7-1D: Vegetation Proposed New Substation Sites Proposed Route BTRICGEGR-N-CapturePortal Carbon

40

Kinetic viscoelasticity modeling applied to degradation during carboncarbon 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.

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

Carbon accumulation of tropical peatlands over millennia: a modeling approach  

E-Print Network [OSTI]

in the global carbon cycle by storing about 4090 Gt C in peat. Over the past several decades, tropical with lowering the water table and peat burning, releasing large amounts of carbon stored in peat the Holocene Peat Model (HPM), which has been successfully applied to northern temperate peatlands. Tropical

42

Slow bainite: an opportunity to determine the carbon content of the bainitic ferrite during growth  

SciTech Connect (OSTI)

The amount of carbon in solid solution in bainitic ferrite at the early stage of transformation has been directly determined by atom probe tomography at 200 C, taking advantage of the extremely slow transformation kinetics of a novel nanocrystalline steel. Results demonstrated that the original bainitic ferrite retains much of the carbon content of the parent austenite providing strong evidence that bainite transformation is essentially displacive in nature. In this work, the carbon content of the bainitic ferrite away from any carbon-enriched regions has been determined by atom probe tomography as the bainite transformation progresses at 200 C in this nanocrystalline steel. Results provide experimental evidence for the mechanism controlling bainitic ferrite growth in steels.

Caballero, Francesca G. [CENIM-CSIC, Madrid, Spain; Miller, Michael K [ORNL; Garcia-Mateo, C. [CENIM-CSIC, Madrid, Spain

2011-01-01T23:59:59.000Z

43

Statistical Correlation and Modelling of Carbonate Heterogeneity  

E-Print Network [OSTI]

In many carbonate reservoirs, much of the porosity is in the form of micropores (with diameter 1-10 microns). This porosity lies far below the resolution of any conventional wireline logging tools and can only be observed ...

Price, David P

2009-01-01T23:59:59.000Z

44

A method for the determination of dissolved organic carbon in sea water by gas chromatography  

E-Print Network [OSTI]

of organic matter was carried out at elevated temperature and pressure after collection of a large number of samples. The resulting carbon dioxide was flushed through a gas chromatograph with helium as the carrier gas and the signal was recorded on a strip... chart recorder. Chromatographic analysis time was approximately eleven minutes per sample with a precision of + Q. 1 mg C/l. The organic carbon content of the sample was determined by measurement of the peak area using an appropriate carbon dioxide...

Fredericks, Alan D

1965-01-01T23:59:59.000Z

45

Modeling Carbon Nanotubes in Injection Molding | ornl.gov  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Modeling Carbon Nanotubes in Injection Molding Feb 03 2015 11:00 AM - 11:30 AM Lukas Bystricky, Florida State University Computer Science and Mathematics Division Computational and...

46

A Continuum Model for Carbon Nanotube-Infused Polyimides  

E-Print Network [OSTI]

A Continuum Model for Carbon Nanotube-Infused Polyimides Heather Wilson1 , Sumanth Banda2 , Ralph C, the materials need to withstand this process. The nanotube-infused polyimides are flexible enough to withstand

47

Substrate and environmental controls on microbial assimilation of soil organic carbon: a framework for Earth System Models  

SciTech Connect (OSTI)

Microbial assimilation of soil organic carbon is one of the fundamental processes of global carbon cycling and it determines the magnitude of microbial biomass in soils. Mechanistic understanding of microbial assimilation of soil organic carbon and its controls is important for to improve Earth system models ability to simulate carbon-climate feedbacks. Although microbial assimilation of soil organic carbon is broadly considered to be an important parameter, it really comprises two separate physiological processes: one-time assimilation efficiency and time-dependent microbial maintenance energy. Representing of these two mechanisms is crucial to more accurately simulate carbon cycling in soils. In this study, a simple modeling framework was developed to evaluate the substrate and environmental controls on microbial assimilation of soil organic carbon using a new term: microbial annual active period (the length of microbes remaining active in one year). Substrate quality has a positive effect on microbial assimilation of soil organic carbon: higher substrate quality (lower C:N ratio) leads to higher ratio of microbial carbon to soil organic carbon and vice versa. Increases in microbial annual active period from zero stimulate microbial assimilation of soil organic carbon; however, when microbial annual active period is longer than an optimal threshold, increasing this period decreases microbial biomass. The simulated ratios of soil microbial biomass to soil organic carbon are reasonably consistent with a recently compiled global dataset at the biome-level. The modeling framework of microbial assimilation of soil organic carbon and its controls developed in this study offers an applicable ways to incorporate microbial contributions to the carbon cycling into Earth system models for simulating carbon-climate feedbacks and to explain global patterns of microbial biomass.

Xu, Xiaofeng [ORNL] [ORNL; Schimel, Joshua [University of California, Santa Barbara] [University of California, Santa Barbara; Thornton, Peter E [ORNL] [ORNL; Song, Xia [ORNL] [ORNL; Yuan, Fengming [ORNL] [ORNL; Goswami, Santonu [ORNL] [ORNL

2014-01-01T23:59:59.000Z

48

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

SciTech Connect (OSTI)

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

49

Determination and mapping of diameter and helicity for single-walled carbon nanotubes using nanobeam electron diffraction  

E-Print Network [OSTI]

of the formation energy of carbon nanotubes, while the growth prefers slightly the structure with helicity 15Determination and mapping of diameter and helicity for single-walled carbon nanotubes using June 2005 The atomic structures of 124 single-walled carbon nanotubes, described by their diameter

Qin, Lu-Chang

50

Deep-Sea Research II 50 (2003) 655674 Determining true particulate organic carbon: bottles, pumps  

E-Print Network [OSTI]

Deep-Sea Research II 50 (2003) 655­674 Determining true particulate organic carbon: bottles, pumps or by in situ filtration with pumps and analyzing the filters. The concentrations measured by these two methods-latitude waters. Here we report that the ratio of bottle POC to pump POC ranged between 20 and 200 in the Ross Sea

Hansell, Dennis

51

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...

Pickle, Brent Durrell

2005-02-17T23:59:59.000Z

52

Temperature determination from the lattice gas model  

E-Print Network [OSTI]

Determination of temperature from experimental data has become important in searches for critical phenomena in heavy ion collisions. Widely used methods are ratios of isotopes (which rely on chemical and thermal equilibrium), population ratios of excited states etc. Using the lattice gas model we propose a new observable: $n_{ch}/Z$ where $n_{ch}$ is the charge multiplicity and $Z$ is the charge of the fragmenting system. We show that the reduced multiplicity is a good measure of the average temperature of the fragmenting system.

S. Das Gupta; J. Pan; M. B. Tsang

1996-09-30T23:59:59.000Z

53

THE CARBON-LAND MODEL INTERCOMPARISON PROJECT (C-LAMP): A PROTOTYPE FOR COUPLED BIOSPHERE-ATMOSPHERE MODEL  

E-Print Network [OSTI]

often referred to as Earth System Models (ESMs). While a number of terrestrial and ocean carbon models

Hoffman, Forrest M.

54

Soil carbon sensitivity to temperature and carbon use efficiency compared across microbial-ecosystem models of varying complexity  

SciTech Connect (OSTI)

Global ecosystem models may require microbial components to accurately predict feedbacks between climate warming and soil decomposition, but it is unclear what parameters and levels of complexity are ideal for scaling up to the globe. Here we conducted a model comparison using a conventional model with first-order decay and three microbial models of increasing complexity that simulate short- to long-term soil carbon dynamics. We focused on soil carbon responses to microbial carbon use efficiency (CUE) and temperature. Three scenarios were implemented in all models: constant CUE (held at 0.31), varied CUE ( 0.016 C 1), and 50 % acclimated CUE ( 0.008 C 1). Whereas the conventional model always showed soil carbon losses with increasing temperature, the microbial models each predicted a temperature threshold above which warming led to soil carbon gain. The location of this threshold depended on CUE scenario, with higher temperature thresholds under the acclimated and constant scenarios. This result suggests that the temperature sensitivity of CUE and the structure of the soil carbon model together regulate the long-term soil carbon response to warming. Equilibrium soil carbon stocks predicted by the microbial models were much less sensitive to changing inputs compared to the conventional model. Although many soil carbon dynamics were similar across microbial models, the most complex model showed less pronounced oscillations. Thus, adding model complexity (i.e. including enzyme pools) could improve the mechanistic representation of soil carbon dynamics during the transient phase in certain ecosystems. This study suggests that model structure and CUE parameterization should be carefully evaluated when scaling up microbial models to ecosystems and the globe.

Li, Jianwei [University of Oklahoma] [University of Oklahoma; Wang, Gangsheng [ORNL] [ORNL; Allison, Steven D. [University of California, Irvine] [University of California, Irvine; Mayes, Melanie [ORNL] [ORNL; Luo, Yiqi [University of Oklahoma] [University of Oklahoma

2014-01-01T23:59:59.000Z

55

Modeling of Acid Fracturing in Carbonate Reservoirs  

E-Print Network [OSTI]

The acid fracturing process is a thermal, hydraulic, mechanical, and geochemical (THMG)-coupled phenomena in which the behavior of these variables are interrelated. To model the flow behavior of an acid into a fracture, mass and momentum balance...

Al Jawad, Murtada s

2014-06-05T23:59:59.000Z

56

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

SciTech Connect (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

57

Kinetic model of catalytic oxidation of carbon monoxide on nickel  

SciTech Connect (OSTI)

A mechanism is proposed for describing the previous disclosed multiplicity of equilibrium states in the oxidation of carbon monoxide on metallic nickel. In contrast to the known mechanism for oxidation of CO on platinum metals it includes a nonlinear stage of carbon monoxide adsorption and a linear stage of oxygen adsorption. A kinetic model has been obtained and stage velocity constants have been found, providing a basis for obtaining a quantitative agreement between the calculated and experimental relations between the reaction velocity and the reagent concentrations. Opinions are stated in relation to the causes for evolution of the CO oxidation reaction from platinum metals to nickel.

Pyatnitskii, Yu.I.; Ostapyuk, V.A.

1986-07-01T23:59:59.000Z

58

Increase of Carbon Cycle Feedback with Climate Sensitivity: Results from a coupled Climate and Carbon Cycle Model  

SciTech Connect (OSTI)

Coupled climate and carbon cycle modeling studies have shown that the feedback between global warming and the carbon cycle, in particular the terrestrial carbon cycle, could accelerate climate change and result in larger warming. In this paper, we investigate the sensitivity of this feedback for year-2100 global warming in the range of 0 K to 8 K. Differing climate sensitivities to increased CO{sub 2} content are imposed on the carbon cycle models for the same emissions. Emissions from the SRES A2 scenario are used. We use a fully-coupled climate and carbon cycle model, the INtegrated Climate and CArbon model (INCCA) the NCAR/DOE Parallel Coupled Model coupled to the IBIS terrestrial biosphere model and a modified-OCMIP ocean biogeochemistry model. In our model, for scenarios with year-2100 global warming increasing from 0 to 8 K, land uptake decreases from 47% to 29% of total CO{sub 2} emissions. Due to competing effects, ocean uptake (16%) shows almost no change at all. Atmospheric CO{sub 2} concentration increases were 48% higher in the run with 8 K global climate warming than in the case with no warming. Our results indicate that carbon cycle amplification of climate warming will be greater if there is higher climate sensitivity to increased atmospheric CO{sub 2} content; the carbon cycle feedback factor increases from 1.13 to 1.48 when global warming increases from 3.2 to 8 K.

Govindasamy, B; Thompson, S; Mirin, A; Wickett, M; Caldeira, K; Delire, C

2004-04-01T23:59:59.000Z

59

Macro scale physical model of nanoindentation on vertically aligned carbon nanotube forests  

E-Print Network [OSTI]

Currently the process of nanoindentation is being explored as a reliable means of determining the mechanical properties of carbon nanotubes (CNTs) and the constituent tubes of vertically aligned carbon nanotube (VACNT) ...

Ebeling, Geoffrey F. (Geoffrey Foster), 1981-

2004-01-01T23:59:59.000Z

60

18 Use of Satellite Remote Sensing Data for Modeling Carbon Emissions from Fires: A Perspective in  

E-Print Network [OSTI]

18 Use of Satellite Remote Sensing Data for Modeling Carbon Emissions from Fires: A Perspective of the accurate estimation of carbon emissions from fires. So far, the continental-scale estimates of carbon conventional and satellite data to maximize their utility for fire emission estimation. 18.2 Carbon Emission

Li, Zhanqing

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

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

SciTech Connect (OSTI)

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

62

THE FIRST FLUORINE ABUNDANCE DETERMINATIONS IN EXTRAGALACTIC ASYMPTOTIC GIANT BRANCH CARBON STARS  

SciTech Connect (OSTI)

Fluorine ({sup 19}F) abundances (or upper limits) are derived in six extragalactic asymptotic giant branch (AGB) carbon stars from the HF(1-0) R9 line at 2.3358 {mu}m in high-resolution spectra. The stars belong to the Local Group galaxies, Large Magellanic Cloud, Small Magellanic Cloud, and Carina dwarf spheroidal, spanning more than a factor of 50 in metallicity. This is the first study to probe the behavior of F with metallicity in intrinsic extragalactic C-rich AGB stars. Fluorine could be measured only in four of the target stars, showing a wide range in F enhancements. Our F abundance measurements together with those recently derived in Galactic AGB carbon stars show a correlation with the observed carbon and s-element enhancements. The observed correlations, however, display a different dependence on the stellar metallicity with respect to theoretical predictions in low-mass, low-metallicity AGB models. We briefly discuss the possible reasons for this discrepancy. If our findings are confirmed in a larger number of metal-poor AGBs, the issue of F production in AGB stars will need to be revisited.

Abia, C.; Cristallo, S.; Dominguez, I. [Dpto. Fisica Teorica y del Cosmos, Universidad de Granada, 18071 Granada (Spain); Cunha, K.; Smith, V. V. [National Optical Astronomy Observatory, P.O. Box 26732, Tucson, AZ 85726 (United States); De Laverny, P.; Recio-Blanco, A. [University of Nice-Sophia Antipolis, CNRS (UMR 6202), Cassiopee, Observatoire de la Cote d'Azur, B.P. 4229, 06304 Nice Cedex 4 (France); Straniero, O., E-mail: cabia@ugr.es [INAF-Osservatorio di Collurania, 64100 Teramo (Italy)

2011-08-10T23:59:59.000Z

63

Rippling and a phase-transforming mesoscopic model for multiwalled carbon nanotubes  

E-Print Network [OSTI]

Rippling and a phase-transforming mesoscopic model for multiwalled carbon nanotubes M. Arroyo I 08034, Spain Abstract We propose to model thick multiwalled carbon nanotubes as beams with non- convex transformation, B. beams and columns, B. finite strain, B. multiwalled carbon nanotubes 1 Introduction Since

Huerta, Antonio

64

An XFEM Model for Carbon Sequestration Journal: International Journal for Numerical Methods in Engineering  

E-Print Network [OSTI]

PeerReview Only An XFEM Model for Carbon Sequestration Journal: International Journal for Numerical method, Carbon Sequestration, Multiphase flow, XFEM, Multifield systems, Petrov-Galerkin httpScience (www.interscience.wiley.com). DOI: 10.1002/nme An XFEM Model for Carbon Sequestration Chris Ladubec

Gracie, Robert

65

ECONOMIC MODELING OF THE GLOBAL ADOPTION OF CARBON CAPTURE AND SEQUESTRATION TECHNOLOGIES  

E-Print Network [OSTI]

ECONOMIC MODELING OF THE GLOBAL ADOPTION OF CARBON CAPTURE AND SEQUESTRATION TECHNOLOGIES J. R. Mc of carbon capture and sequestration technologies as applied to electric generating plants. The MIT Emissions, is used to model carbon capture and sequestration (CCS) technologies based on a natural gas combined cycle

66

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

SciTech Connect (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

67

Atomistic Modeling of Hydrogen Storage in Nanostructured Carbons.  

E-Print Network [OSTI]

??Nanoporous carbons are among the widely studied and promising materials on hydrogen storage for on-board vehicles. However, the nature of nanoporous carbon structures, as well (more)

Peng, Lujian

2011-01-01T23:59:59.000Z

68

Integrated Assessment Modeling of Carbon Sequestration and Land Use Emissions Using Detailed Model Results and Observations  

SciTech Connect (OSTI)

This report outlines the progress on the development and application of Integrated Assessment Modeling of Carbon Sequestrations and Land Use Emissions supported by the DOE Office of Biological and Environmental Research (OBER), U.S. Department of Energy, Grant No. DOE-DE-FG02-01ER63069. The overall objective of this collaborative project between the University of Illinois at Urbana-Champaign (UIUC), Oak Ridge National Laboratory (ORNL), Lawrence Livermore National Laboratory (LLNL), and Pacific Northwest National Laboratory (PNNL) was to unite the latest advances in carbon cycle research with scientifically based models and policy-related integrated assessment tools that incorporate computationally efficient representations of the latest knowledge concerning science and emission trajectories, and their policy implications. As part of this research we accomplished the following tasks that we originally proposed: (1) In coordination with LLNL and ORNL, we enhanced the Integrated Science Assessment Model's (ISAM) parametric representation of the ocean and terrestrial carbon cycles that better represent spatial and seasonal variations, which are important to study the mechanisms that influence carbon sequestration in the ocean and terrestrial ecosystems; (2) Using the MiniCAM modeling capability, we revised the SRES (IPCC Special Report on Emission Scenarios; IPCC, 2000) land use emission scenarios; and (3) On the application front, the enhanced version of ISAM modeling capability is applied to understand how short- and long-term natural carbon fluxes, carbon sequestration, and human emissions contribute to the net global emissions (concentrations) trajectories required to reach various concentration (emission) targets. Under this grant, 21 research publications were produced. In addition, this grant supported a number of graduate and undergraduate students whose fundamental research was to learn a disciplinary field in climate change (e.g., ecological dynamics and ocean circulations) and then complete research on how this field could be linked to the other factors we need to consider in its dynamics (e.g., land use, ocean and terrestrial carbon sequestration and climate change).

Dr. Atul Jain

2005-04-17T23:59:59.000Z

69

DOUBLE SHELL TANK (DST) HYDROXIDE DEPLETION MODEL FOR CARBON DIOXIDE ABSORPTION  

SciTech Connect (OSTI)

This document generates a supernatant hydroxide ion depletion model based on mechanistic principles. The carbon dioxide absorption mechanistic model is developed in this report. The report also benchmarks the model against historical tank supernatant hydroxide data and vapor space carbon dioxide data. A comparison of the newly generated mechanistic model with previously applied empirical hydroxide depletion equations is also performed.

OGDEN DM; KIRCH NW

2007-10-31T23:59:59.000Z

70

States of Carbon-12 in the Skyrme Model  

E-Print Network [OSTI]

The Skyrme model has two Skyrmion solutions of baryon number $12$, with $D_{3h}$ and $D_{4h}$ symmetries. The first has an equilateral triangular shape and the second an extended linear shape, analogous to the triangle and linear chain structures of three alpha particles. We recalculate the moments of inertia of these Skyrmions, and deduce the energies and spins of their quantized rotational excitations. There is a good match with the ground-state band of Carbon-12, and with the recently established rotational band of the Hoyle state. The ratio of the root mean square matter radii also matches the experimental value.

P. H. C. Lau; N. S. Manton

2014-11-28T23:59:59.000Z

71

Carbon Nanotube Mats and Fibers with Irradiation-Improved Mechanical Characteristics: ATheoretical Model  

E-Print Network [OSTI]

Carbon Nanotube Mats and Fibers with Irradiation-Improved Mechanical Characteristics: ATheoretical model to calculate mechanical characteristics of macroscopic mats and fibers of single-walled carbon-flow technique [4]. The SWNT fibers, which in contrast to most ordinary carbon fibers could be strongly bent with

Krasheninnikov, Arkady V.

72

Shielding-Effectiveness Modeling of Carbon-Fiber/Nylon-6,6 Composites  

E-Print Network [OSTI]

Shielding-Effectiveness Modeling of Carbon-Fiber/Nylon- 6,6 Composites Nicholas B. Janda,1 Jason M for various amounts of Thermal- Graph DKD X carbon fiber within nylon 6,6. The theory predicts that the most important parameters for the shield- ing effectiveness of a sample are the carbon-fiber volume percentage

Perger, Warren F.

73

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-making that accounts for both cost and carbon footprint. We examine how the values of these parameters as well or shareholders, are undertaking initiatives to reduce their carbon footprint. However, these initiatives have

Benjaafar, Saifallah

74

Evaluating carbon sequestration efficiency in an ocean circulation model by adjoint sensitivity analysis  

E-Print Network [OSTI]

Evaluating carbon sequestration efficiency in an ocean circulation model by adjoint sensitivity the application of the adjoint method to develop three-dimensional maps of carbon sequestration efficiency. Sequestration efficiency (the percentage of carbon injected at a continuous point source that remains

Follows, Mick

75

Back to Exploration 2008 CSPG CSEG CWLS Convention 1 A Computational Model of Catalyzed Carbon Sequestration  

E-Print Network [OSTI]

explores the feasibility of catalysis-based carbon sequestration by efficiently and accurately modeling that this method can be scaled to accurately predict the efficacy of such systems for carbon sequestration to help find the most cost effective methods possible. Most carbon sequestration methods are capture

Spiteri, Raymond J.

76

Modeling impacts of carbon sequestration on net greenhouse gas emissions from agricultural soils in China  

E-Print Network [OSTI]

Modeling impacts of carbon sequestration on net greenhouse gas emissions from agricultural soils impacts of carbon sequestration on net greenhouse gas emissions from agricultural soils in China, Global Biogeochem. Cycles, 23, GB1007, doi:10.1029/2008GB003180. 1. Introduction [2] Carbon (C) sequestration has

77

January 2, 2008 Numerical modeling of the effect of carbon dioxide  

E-Print Network [OSTI]

January 2, 2008 Numerical modeling of the effect of carbon dioxide sequestration on the rate souterrain de dioxyde de carbone sur la dformation des calcaires par dissolution sous contrainte: rsultats;Abstract When carbon dioxide (CO2) is injected into an aquifer or a depleted geological reservoir, its

Boyer, Edmond

78

Predicting the net carbon exchanges of crop rotations in Europe with an agro-ecosystem model  

E-Print Network [OSTI]

Predicting the net carbon exchanges of crop rotations in Europe with an agro-ecosystem model S.Lehuger@art.admin.ch. Fax: (+41) 44 377 72 01. Phone: (+41) 44 377 75 13. hal-00414342,version2-1Sep2010 #12;Abstract Carbon and measuring land-atmosphere carbon exchanges from arable lands are important tasks to predict the influence

Boyer, Edmond

79

Changes in soil organic carbon storage predicted by Earth system models during the 21st century  

E-Print Network [OSTI]

carbon changes in Earth system models K. E. O. Todd-Brown etcarbon changes in Earth system models K. E. O. Todd-Brown etcarbon changes in Earth system models K. E. O. Todd-Brown et

2013-01-01T23:59:59.000Z

80

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

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

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

SciTech Connect (OSTI)

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

82

Forest cover, carbon sequestration, and wildlife habitat: policy review and modeling of tradeoffs among land-use  

E-Print Network [OSTI]

Forest cover, carbon sequestration, and wildlife habitat: policy review and modeling of tradeoffs and services, including timber production, carbon sequestration and storage, scenic amenities, and wildlife habitat. International efforts to mitigate climate change through forest carbon sequestration

Rissman, Adena

83

AN INTEGRATED MODELING FRAMEWORK FOR CARBON MANAGEMENT TECHNOLOGIES  

SciTech Connect (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

84

Determination of iridium in industrial concentrates by controlled-potential coulometry with a glassy-carbon electrode  

SciTech Connect (OSTI)

The authors present a coulometric method for determining iridium without separating nonferrous and noble metals using a glassy-carbon (GC) crucible instead of the expensive platinum electrode. The crucible also serves as the electrochemical cell for the coulometric determination and as a vessel in which an aliquot weight of the analyzed solution is taken. The KP-3 concentrate contains several metals that accompany iridium. The main metals which interfere in the electrochemical determination of iridium with the use of a platinum electrode are iron and ruthenium. This paper describes the authors' proposed procedure for determining iridium in hydrochloric acid solutions with the GC crucible-electrode.

Stril'chenko, T.G.; Kabanova, O.L.; Danilova, F.I.

1987-02-01T23:59:59.000Z

85

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

SciTech Connect (OSTI)

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 Darcys 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

2012-05-15T23:59:59.000Z

86

CARBON DEFLAGRATION IN TYPE Ia SUPERNOVA. I. CENTRALLY IGNITED MODELS  

SciTech Connect (OSTI)

A leading model for Type Ia supernovae (SNe Ia) begins with a white dwarf near the Chandrasekhar mass that ignites a degenerate thermonuclear runaway close to its center and explodes. In a series of papers, we shall explore the consequences of ignition at several locations within such dwarfs. Here we assume central ignition, which has been explored before, but is worth revisiting, if only to validate those previous studies and to further elucidate the relevant physics for future work. A perturbed sphere of hot iron ash with a radius of {approx}100 km is initialized at the middle of the star. The subsequent explosion is followed in several simulations using a thickened flame model in which the flame speed is either fixed-within the range expected from turbulent combustion-or based on the local turbulent intensity. Global results, including the explosion energy and bulk nucleosynthesis (e.g., {sup 56}Ni of 0.48-0.56 M{sub Sun }) turn out to be insensitive to this speed. In all completed runs, the energy released by the nuclear burning is adequate to unbind the star, but not enough to give the energy and brightness of typical SNe Ia. As found previously, the chemical stratification observed in typical events is not reproduced. These models produce a large amount of unburned carbon and oxygen in central low velocity regions, which is inconsistent with spectroscopic observations, and the intermediate mass elements and iron group elements are strongly mixed during the explosion.

Ma, H.; Woosley, S. E.; Malone, C. M. [Department of Astronomy and Astrophysics, University of California, Santa Cruz, CA 95064 (United States); Almgren, A.; Bell, J. [Center for Computational Sciences and Engineering, Lawrence Berkeley National Lab, Berkeley, CA 94720 (United States)

2013-07-01T23:59:59.000Z

87

A Finite Element Model for Simulation of Carbon Dioxide Sequestration  

SciTech Connect (OSTI)

We present a hydro-mechanical model, followed by stress, deformation, and shear-slip failure analysis for geological sequestration of carbon dioxide (CO2). The model considers the poroelastic effects by taking into account of the two-way coupling between the geomechanical response and the fluid flow process. Analytical solutions for pressure and deformation fields were derived for a typical geological sequestration scenario in our previous work. A finite element approach is introduced here for numerically solving the hydro-mechanical model with arbitrary boundary conditions. The numerical approach was built on an open-source finite element code Elmer, and results were compared to the analytical solutions. The shear-slip failure analysis was presented based on the numerical results, where the potential failure zone is identified. Information is relevant to the prediction of the maximum sustainable injection rate or pressure. The effects of caprock permeability on the fluid pressure, deformation, stress, and the shear-slip failure zone were also quantitatively studied. It was shown that a larger permeability in caprock and base rock leads to a larger uplift but a smaller shear-slip failure zone.

Bao, Jie; Xu, Zhijie; Fang, Yilin

2013-11-02T23:59:59.000Z

88

Using tracer experiments to determine deep saline aquifers caprocks transport characteristics for carbon dioxide storage  

E-Print Network [OSTI]

for carbon dioxide storage P. Bachaud1,2 , Ph. Berne1 , P. Boulin1,3,4 , F. Renard5,6 , M. Sardin2 , J

Boyer, Edmond

89

A Mathematical Model of OxideCarbon Composite Electrode for Supercapacitors  

E-Print Network [OSTI]

A Mathematical Model of Oxide?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.

90

Determination of the permeability of carbon aerogels by gas flow measurements  

SciTech Connect (OSTI)

Carbon aerogels are synthesized via the polycondensation of resorcinol and formaldehyde, followed by supercritical drying and pyrolysis at 1050{degree}C in nitrogen. Because of their interconnected porosity, ultrafine cell structure and high surface area, carbon aerogels have many potential applications, such as in supercapacitors, battery electrodes, catalyst supports, and gas filters. The performance of carbon aerogels in the latter two applications depends on the permeability or gas flow conductance in these materials. By measuring the pressure differential across a thin specimen and the nitrogen gas flow rate in the viscous regime, we calculated the permeability of carbon aerogels from equations based upon Darcy`s law. Our measurements show that carbon aerogels have apparent permeabilities on the order of 10{sup {minus}12}to 10{sup {minus}10} cm{sup 2} for densities ranging from 0.44 to 0.05 g/cm{sup 3}. Like their mechanical properties, the permeability of carbon aerogels follows a power law relationship with density and average pore size. Such findings help us to estimate the average pore sizes of carbon aerogels once their densities are known. This paper reveals the relationships among permeability, pore size and density in carbon aerogels.

Kong, F.M.; Hulsey, S.S.; Alviso, C.T.; Pekala, R.W.

1992-04-01T23:59:59.000Z

91

Determination of the permeability of carbon aerogels by gas flow measurements  

SciTech Connect (OSTI)

Carbon aerogels are synthesized via the polycondensation of resorcinol and formaldehyde, followed by supercritical drying and pyrolysis at 1050{degree}C in nitrogen. Because of their interconnected porosity, ultrafine cell structure and high surface area, carbon aerogels have many potential applications, such as in supercapacitors, battery electrodes, catalyst supports, and gas filters. The performance of carbon aerogels in the latter two applications depends on the permeability or gas flow conductance in these materials. By measuring the pressure differential across a thin specimen and the nitrogen gas flow rate in the viscous regime, we calculated the permeability of carbon aerogels from equations based upon Darcy's law. Our measurements show that carbon aerogels have apparent permeabilities on the order of 10{sup {minus}12}to 10{sup {minus}10} cm{sup 2} for densities ranging from 0.44 to 0.05 g/cm{sup 3}. Like their mechanical properties, the permeability of carbon aerogels follows a power law relationship with density and average pore size. Such findings help us to estimate the average pore sizes of carbon aerogels once their densities are known. This paper reveals the relationships among permeability, pore size and density in carbon aerogels.

Kong, F.M.; Hulsey, S.S.; Alviso, C.T.; Pekala, R.W.

1992-04-01T23:59:59.000Z

92

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

2012-01-27T23:59:59.000Z

93

Multi-century Changes to Global Climate and Carbon Cycle: Results from a Coupled Climate and Carbon Cycle Model  

SciTech Connect (OSTI)

In this paper, we use a coupled climate and carbon cycle model to investigate the global climate and carbon cycle changes out to year 2300 that would occur if CO{sub 2} emissions from all the currently estimated fossil fuel resources were released to the atmosphere. By year 2300, the global climate warms by about 8 K and atmospheric CO{sub 2} reaches 1423 ppmv. The warming is higher than anticipated because the sensitivity to radiative forcing increases as the simulation progresses. In our simulation, the rate of emissions peak at over 30 PgC yr{sup -1} early in the 22nd century. Even at year 2300, nearly 50% of cumulative emissions remain in the atmosphere. In our simulations both soils and living biomass are net carbon sinks throughout the simulation. Despite having relatively low climate sensitivity and strong carbon uptake by the land biosphere, our model projections suggest severe long-term consequences for global climate if all the fossil-fuel carbon is ultimately released to the atmosphere.

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

2005-02-17T23:59:59.000Z

94

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...

Johnston, Travis Wayne 1987-

2012-11-01T23:59:59.000Z

95

ORNL/CDIAC-150 DETERMINATION OF CARBON DIOXIDE, HYDROGRAPHIC, AND CHEMICAL  

E-Print Network [OSTI]

Center Oak Ridge National Laboratory Oak Ridge, Tennessee, USA Date Published: March 2006 Prepared by the Carbon Dioxide Information Analysis Center OAK RIDGE NATIONAL LABORATORY Oak Ridge, Tennessee 37831

96

Ecosystem carbon storage capacity as affected by disturbance regimes: A general theoretical model  

SciTech Connect (OSTI)

Disturbances have been recognized as a key factor shaping terrestrial ecosystem states and dynamics. A general model that quantitatively describes the relationship between carbon storage and disturbance regime is critical for better understanding large scale terrestrial ecosystem carbon dynamics. We developed a model (REGIME) to quantify ecosystem carbon storage capacities (E[x]) under varying disturbance regimes with an analytical solution E[x] = U {center_dot} {tau}{sub E} {center_dot} {lambda}{lambda} + s {tau} 1, where U is ecosystem carbon influx, {tau}{sub E} is ecosystem carbon residence time, and {tau}{sub 1} is the residence time of the carbon pool affected by disturbances (biomass pool in this study). The disturbance regime is characterized by the mean disturbance interval ({lambda}) and the mean disturbance severity (s). It is a Michaelis-Menten-type equation illustrating the saturation of carbon content with mean disturbance interval. This model analytically integrates the deterministic ecosystem carbon processes with stochastic disturbance events to reveal a general pattern of terrestrial carbon dynamics at large scales. The model allows us to get a sense of the sensitivity of ecosystems to future environmental changes just by a few calculations. According to the REGIME model, for example, approximately 1.8 Pg C will be lost in the high-latitude regions of North America (>45{sup o} N) if fire disturbance intensity increases around 5.7 time the current intensity to the end of the twenty-first century, which will require around 12% increases in net primary productivity (NPP) to maintain stable carbon stocks. If the residence time decreased 10% at the same time additional 12.5% increases in NPP are required to keep current C stocks. The REGIME model also lays the foundation for analytically modeling the interactions between deterministic biogeochemical processes and stochastic disturbance events.

Weng, Ensheng [University of Oklahoma, Norman; Luo, Yiqi [University of Oklahoma; Wang, Weile [NASA Ames Research Center; Wang, Han [University of Oklahoma, Norman; Hayes, Daniel J [ORNL; McGuire, A. David [University of Alaska; Hastings, Alan [University of California, Davis; Schimel, David [NEON Inc.

2012-01-01T23:59:59.000Z

97

Electrical utilities model for determining electrical distribution capacity  

SciTech Connect (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

98

Carbon-nitrogen interactions regulate climate-carbon cycle feedbacks: results from an atmosphere-ocean general circulation model  

E-Print Network [OSTI]

2009 P. E. Thornton et al. : Carbon-nitrogen interactionsregulate climate-carbon cycle feedbacks Monfray, P. ,T. H. : A global ocean carbon climatology: Results from

2009-01-01T23:59:59.000Z

99

Continuum Models of Carbon Nanotube-Based Composites Using the Boundary Element Method  

E-Print Network [OSTI]

Continuum Models of Carbon Nanotube-Based Composites Using the Boundary Element Method Y.J. Liu)-based composites. Carbon nanotubes, formed conceptually by rolling thin graphite sheets, have been found to be extremely stiff, strong and resilient, and therefore may be ideal for reinforcing composite materials

Liu, Yijun

100

"How Can Earth Observation Data Be Implemented To Improve Parameterisation of Carbon Models"  

E-Print Network [OSTI]

"How Can Earth Observation Data Be Implemented To Improve Parameterisation of Carbon Models practices, afforestation and reforestation. The quantification of the strength of carbon uptake by forests is therefore important if we intend to offset emissions by the management of forests for sequestration. Current

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 modelling approach to carbon, water and energy feedbacks and interactions across the  

E-Print Network [OSTI]

) Advanced Very High Resolution Radiometer BOREAS - (the) BOReal Ecosystem-Atmosphere Study C - Carbon CABi A modelling approach to carbon, water and energy feedbacks and interactions across the land partitioning of energy, the evapotranspiration of water and if the land-surface is a sink or a source of CO2

102

A mixed finite element discretization scheme for a concrete carbonation model with concentration-dependent porosity  

E-Print Network [OSTI]

A mixed finite element discretization scheme for a concrete carbonation model with concentration/unsaturated porous media. The special features of our problem are twofold: the reaction produces water and therefore for the case of concrete carbonation ­ one of the most important physico-chemical processes affecting

Suciu, Nicolae

103

Non-parametric regression and neural-network inll drilling recovery models for carbonate reservoirs  

E-Print Network [OSTI]

, and operations e- ciency. Consequent to the primary recovery, water- ¯ood is often used as a secondary recoveryNon-parametric regression and neural-network in®ll drilling recovery models for carbonate ultimate oil recovery from reservoirs in San Andres and Clearfork carbonate formations in West Texas

Valkó, Peter

104

Evaluating variable switching and flash methods in modeling carbon sequestration in deep geologic formations  

E-Print Network [OSTI]

Evaluating variable switching and flash methods in modeling carbon sequestration in deep geologic performance computing to assess the risks involved in carbon sequestration in deep geologic formations-thermal- chemical processes in variably saturated, non-isothermal porous media is applied to sequestration

Mills, Richard

105

Mathematical Modeling of Carbon Dioxide Injection in the Subsurface for Improved Hydrocarbon Recovery and Sequestration  

E-Print Network [OSTI]

Mathematical Modeling of Carbon Dioxide Injection in the Subsurface for Improved Hydrocarbon Recovery and Sequestration Philip C. Myint, Laurence Rongy, Kjetil B. Haugen, Abbas Firoozabadi Department. Combustion of fossil fuels contributes to rising atmospheric carbon dioxide (CO2) levels that have been

Firoozabadi, Abbas

106

The impact of the Self-Determined Learning Model of Instruction on student self-determination  

E-Print Network [OSTI]

multifaceted construct and interventions that achieve the best outcomes are multicomponent interventions. The SDLMI (Wehmeyer et al., 2000) is a model of teaching (i.e., intended for teachers as end users to guide and direct instruction) that supports teachers... the impact of the SDLMI (Wehmeyer et al., 2000) on self-determination. Project personnel contacted school districts, and districts that agreed to participate ( < 20) identi- fied high school campuses {n < 39) to participate. Next, the primary district...

Wehmeyer, Michael L.; Shogren, Karrie A.; Palmer, Susan B.; Williams-Diehm, Kendra; Little, Todd D.; Boulton, Aaron Jacob

2012-01-01T23:59:59.000Z

107

Global Biogeochemistry Models and Global Carbon Cycle Research at Lawrence Livermore National Laboratory  

SciTech Connect (OSTI)

The climate modeling community has long envisioned an evolution from physical climate models to ''earth system'' models that include the effects of biology and chemistry, particularly those processes related to the global carbon cycle. The widely reproduced Box 3, Figure 1 from the 2001 IPCC Scientific Assessment schematically describes that evolution. The community generally accepts the premise that understanding and predicting global and regional climate change requires the inclusion of carbon cycle processes in models to fully simulate the feedbacks between the climate system and the carbon cycle. Moreover, models will ultimately be employed to predict atmospheric concentrations of CO{sub 2} and other greenhouse gases as a function of anthropogenic and natural processes, such as industrial emissions, terrestrial carbon fixation, sequestration, land use patterns, etc. Nevertheless, the development of coupled climate-carbon models with demonstrable quantitative skill will require a significant amount of effort and time to understand and validate their behavior at both the process level and as integrated systems. It is important to consider objectively whether the currently proposed strategies to develop and validate earth system models are optimal, or even sufficient, and whether alternative strategies should be pursued. Carbon-climate models are going to be complex, with the carbon cycle strongly interacting with many other components. Off-line process validation will be insufficient. As was found in coupled atmosphere-ocean GCMs, feedbacks between model components can amplify small errors and uncertainties in one process to produce large biases in the simulated climate. The persistent tropical western Pacific Ocean ''double ITCZ'' and upper troposphere ''cold pole'' problems are examples. Finding and fixing similar types of problems in coupled carbon-climate models especially will be difficult, given the lack of observations required for diagnosis and validation of biogeochemical processes.

Covey, C; Caldeira, K; Guilderson, T; Cameron-Smith, P; Govindasamy, B; Swanston, C; Wickett, M; Mirin, A; Bader, D

2005-05-27T23:59:59.000Z

108

Modeling of Seismic Signatures of Carbonate Rock Types  

E-Print Network [OSTI]

Carbonate reservoirs of different rock types have wide ranges of porosity and permeability, creating zones with different reservoir quality and flow properties. This research addresses how seismic technology can be used to identify different...

Jan, Badr H.

2011-02-22T23:59:59.000Z

109

Sensitivity of injection costs to input petrophysical parameters in numerical geologic carbon sequestration models  

SciTech Connect (OSTI)

Numerical simulations are widely used in feasibility studies for geologic carbon sequestration. Accurate estimates of petrophysical parameters are needed as inputs for these simulations. However, relatively few experimental values are available for CO2-brine systems. Hence, a sensitivity analysis was performed using the STOMP numerical code for supercritical CO2 injected into a model confined deep saline aquifer. The intrinsic permeability, porosity, pore compressibility, and capillary pressure-saturation/relative permeability parameters (residual liquid saturation, residual gas saturation, and van Genuchten alpha and m values) were varied independently. Their influence on CO2 injection rates and costs were determined and the parameters were ranked based on normalized coefficients of variation. The simulations resulted in differences of up to tens of millions of dollars over the life of the project (i.e., the time taken to inject 10.8 million metric tons of CO2). The two most influential parameters were the intrinsic permeability and the van Genuchten m value. Two other parameters, the residual gas saturation and the residual liquid saturation, ranked above the porosity. These results highlight the need for accurate estimates of capillary pressure-saturation/relative permeability parameters for geologic carbon sequestration simulations in addition to measurements of porosity and intrinsic permeability.

Cheng, C. L.; Gragg, M. J.; Perfect, E.; White, Mark D.; Lemiszki, P. J.; McKay, L. D.

2013-08-24T23:59:59.000Z

110

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...

Gaddamanugu, Dhatri

2010-07-14T23:59:59.000Z

111

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

E-Print Network [OSTI]

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...

Tran, Hau

2013-05-07T23:59:59.000Z

112

Modelling Urban scale Retrofit, Pathways to 2050 Low Carbon Residential Building Stock  

E-Print Network [OSTI]

A bottom up engineering modelling approach has been used to investigate the pathways to 2050 low carbon residential building stock. The impact of housing retrofit, renewable technologies, occupant behaviour, and grid decarbonisation is measured at a...

Lannon, Simon; Georgakaki, Aliki; Macdonald, Stuart

113

A model of light interception and carbon balance for a sweet chestnut coppice (Castanea sativa Mill.)  

E-Print Network [OSTI]

A model of light interception and carbon balance for a sweet chestnut coppice (Castanea sativa Mill photosynthesis, wood respiration and aerial growth in a sweet chestnut (Castanea sativa Mill.) coppice

Paris-Sud XI, Université de

114

Carbon-nitrogen interactions regulate climate-carbon cycle feedbacks: results from an atmosphere-ocean general circulation model  

E-Print Network [OSTI]

forests indi- cates that the model representation of competition between plants and microbes for new mineral nitrogen resources is reasonable. Our results suggest a weaker dependence of net land carbon flux on soil moisture changes in tropical regions... National Laboratory, Oak Ridge, TN 37831-6335, USA 2Department of Marine Chemistry and Geochemistry, Woods Hole Oceanographic Institution, Woods Hole, MA 02543-1543, USA 3Climate and Global Dynamics Division, National Center for Atmospheric Research...

Thornton, P. E.; Doney, S. C.; Lindsay, Keith; Moore, J. K.; Mahowald, N. M.; Randerson, J. T.; Fung, I.; Lamarque, J. F.; Feddema, Johannes J.

2009-01-01T23:59:59.000Z

115

A mathematical model for countercurrent moving-bed activated carbon adsorption  

E-Print Network [OSTI]

the column. There was insufficient data taken to verify this model. The testing procedure was limited by the approximate uniformity of the influent concentrations in the pilot plant and the effect of the activated carbon concentration and initial solute...A MATHEMATICAL MODEL FOR COUNTERCURRENT MOVING-BED ACTIVATED CARBON ADSORPTION A Thesis by DOUGLAS HAROLD ANDERSON Submitted to the Graduate College of Texas ASM University in partial fulfillment of the requirement for the degree of MASTER...

Anderson, Douglas Harold

1976-01-01T23:59:59.000Z

116

Molecular Modelling of Adsorption and Transport in Nanoporous Carbons: From the Simple Slit Pore Model to Virtual Porous Carbons  

E-Print Network [OSTI]

of energy derived from solar and other intermittent renewable sources, water remediation and desalination, South Australia, Australia, 5005. mark.biggs@adelaide.edu.au Nanoporous carbons are relatively inert

Adler, Joan

117

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

118

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

SciTech Connect (OSTI)

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

119

A validation of heat and carbon fluxes from highresolution land surface and regional models  

E-Print Network [OSTI]

) or regional climate models (RCMs) [Alessandri et al., 2007; Steiner et al., 2009]. [3., 2006; Alessandri et al., 2007; Jarlan et al., 2008; Steiner et al., 2009]. However, the SVAT models models do not account for the role of terrestrial vegetation in the carbon cycle variability [Alessandri

D'Andrea, Fabio

120

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

SciTech Connect (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

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

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

SciTech Connect (OSTI)

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

122

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

DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

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

123

Soil carbon sensitivity to temperature and carbon use efficiency compared across microbial-ecosystem models  

E-Print Network [OSTI]

, accounting for the response of microbial communities to environmental parameters in Earth system models may

German, Donovan P.

124

Multi-Phase CFD Modeling of Solid Sorbent Carbon Capture System  

SciTech Connect (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

125

Multi-phase CFD modeling of solid sorbent carbon capture system  

SciTech Connect (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 EulerianEulerian and EulerianLagrangian 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 EulerianLagrangian simulations (DDPM) are unstable for the given reactor design; while the BARRACUDA EulerianLagrangian model is able to simulate the system given appropriate simplifying assumptions. FLUENT EulerianEulerian simulations also provide a stable solution for the carbon capture reactor given the appropriate simplifying assumptions.

Ryan, E. M.; DeCroix, D.; Breault, Ronald W. [U.S. DOE; Xu, W.; Huckaby, E. David [U.S. DOE

2013-01-01T23:59:59.000Z

126

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

E-Print Network [OSTI]

and not a safety hazard. During the summer of 1999, emissions from local waste-incinerators added 14C-CO2 established in 2000 at each of the four sites shown above. Time-zero sampling of organic and mineral horizons and TVA) demonstrate the potential for ecosystem of carbon recycling (S. Trumbore). Objectives 1. Quantify

127

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

E-Print Network [OSTI]

research in the field of carbon capture and storage (CCS)heightened interest in carbon capture and storage (CCS) as areservoirs. To be sure, carbon capture and sequestration is

McCollum, David L; Ogden, Joan M

2006-01-01T23:59:59.000Z

128

Recent Site-Wide Transport Modeling Related to the Carbon Tetrachloride Plume at the Hanford Site  

SciTech Connect (OSTI)

Carbon tetrachloride transport in the unconfined aquifer system at the Hanford Site has been the subject of follow-on studies since the Carbon Tetrachloride Innovative Treatment Remediation Demonstration (ITRD) Program was completed in FY 2002. These scoping analyses were undertaken to provide support for strategic planning and guidance for the more robust modeling needed to obtain a final record of decision (ROD) for the carbon tetrachloride plume in the 200 West Area. This report documents the technical approach and the results of these follow-on, site-wide scale-modeling efforts. The existing site-wide groundwater model was used in this effort. The work extended that performed as part of the ITRD modeling study in which a 200 West Area scale submodel was developed to examine arrival concentrations at an arbitrary boundary between the 200 E and 200 W areas. These scoping analyses extended the analysis to predict the arrival of the carbon tetrachloride plume at the Columbia River. The results of these analyses illustrate the importance of developing field-scale estimates of natural attenuation parameters, abiotic degradation rate and soil/water equilibrium sorption coefficient, for carbon tetrachloride. With these parameters set to zero, carbon tetrachloride concentrations will exceed the compliance limit of 5 ?g/L outside the 200 Area Plateau Waste Management Area, and the aquifer source loading and area of the aquifer affected will continue to grow until arrival rates of carbon tetrachloride equal source release rates, estimated at 33 kg/yr. Results of this scoping analysis show that the natural attenuation parameters are critical in predicting the future movement of carbon tetrachloride from the 200 West Area. Results also show the significant change in predictions between continual source release from the vadose zone and complete source removal.

Bergeron, Marcel P.; Cole, C R.

2005-11-01T23:59:59.000Z

129

Fullerene-like models for microporous carbon Peter J. F. Harris  

E-Print Network [OSTI]

REVIEW Fullerene-like models for microporous carbon Peter J. F. Harris Received: 8 June 2012 with Franklin's original models, which were based on cross-linked graphitic P. J. F. Harris (&) Centre, UK e-mail: p.j.f.harris@reading.ac.uk 123 J Mater Sci DOI 10.1007/s10853-012-6788-1 Author's personal

Harris, Peter J F

130

Peatland carbon cycle responses to hydrological change at time scales from years to centuries: Impacts on model  

E-Print Network [OSTI]

Peatland carbon cycle responses to hydrological change at time scales from years to centuries: Impacts on model simulations and regional carbon budgets By Benjamin N. Sulman A dissertation submitted to the long-term storage of carbon in peat, these ecosystems contain a significant fraction of the global

Wisconsin at Madison, University of

131

Low-Lying Exciton States Determine the Photophysics of Semiconducting Single Wall Carbon Nanotubes  

E-Print Network [OSTI]

, Garry Rumbles, and Michael J. Heben a National Renewable Energy Laboratory, MS 3216, 1617 Cole Boule excited states are strongly bound excitons, with transition energies determined by the SWNT diameter.12 fluorescence quantum yield of the material20 (f * Corresponding author. National Renewable Energy Laboratory

Tretiak, Sergei

132

REACTIVE FLOW IN VUGGY CARBONATES: METHODS AND MODELS APPLIED TO MATRIX ACIDIZING OF CARBONATES  

E-Print Network [OSTI]

and its effect on fluid flow is numerical simulation. A 3D finite difference numerical model is developed based on Darcy-Brinkman formulation (DBF). Using the developed simulator a flow-based inversion approach is implemented to understand the connectivity...

Izgec, Omer

2010-07-14T23:59:59.000Z

133

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

SciTech Connect (OSTI)

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

Development of a coupled thermo-hydro-mechanical model in discontinuous media for carbon sequestration  

SciTech Connect (OSTI)

Geomechanical alteration of porous media is generally ignored for most shallow subsurface applications, whereas CO2 injection, migration, and trapping in deep saline aquifers will be controlled by coupled multifluid flow, energy transfer, and geomechanical processes. The accurate assessment of the risks associated with potential leakage of injected CO2 and the design of effective injection systems requires that we represent these coupled processes within numerical simulators. The objectives of this study were to develop a coupled thermal-hydro-mechanical model into a single software, and to examine the coupling of thermal, hydrological, and geomechanical processes for simulation of CO2 injection into the subsurface for carbon sequestration. A numerical model is developed to couple nonisothermal multiphase hydrological and geomechanical processes for prediction of multiple interconnected processes for carbon sequestration in deep saline aquifers. The geomechanics model was based on Rigid Body-Spring Model (RBSM), one of the discrete methods to model discontinuous rock system. Poissons effect that was often ignored by RBSM was considered in the model. The simulation of large-scale and long-term coupled processes in carbon capture and storage projects requires large memory and computational performance. Global Array Toolkit was used to build the model to permit the high performance simulations of the coupled processes. The model was used to simulate a case study with several scenarios to demonstrate the impacts of considering coupled processes and Poissons effect for the prediction of CO2 sequestration.

Fang, Yilin; Nguyen, Ba Nghiep; Carroll, Kenneth C.; Xu, Zhijie; Yabusaki, Steven B.; Scheibe, Timothy D.; Bonneville, Alain

2013-09-12T23:59:59.000Z

135

A Carbon Corrosion Model to Evaluate the Effect of Steady State and Transient Operation of a Polymer Electrolyte Membrane Fuel Cell  

E-Print Network [OSTI]

A carbon corrosion model is developed based on the formation of surface oxides on carbon and platinum of the polymer electrolyte membrane fuel cell electrode. The model predicts the rate of carbon corrosion under potential hold and potential cycling conditions. The model includes the interaction of carbon surface oxides with transient species like OH radicals to explain observed carbon corrosion trends under normal PEM fuel cell operating conditions. The model prediction agrees qualitatively with the experimental data supporting the hypothesis that the interplay of surface oxide formation on carbon and platinum is the primary driver of carbon corrosion.

Pandy, Arun; Gummalla, Mallika; Atrazhev, Vadim V; Kuzminyh, Nikolay Yu; Sultanov, Vadim I; Burlatsky, Sergei F

2014-01-01T23:59:59.000Z

136

Early Standard Model Measurement and Determination of Standard Model Background for Searches  

E-Print Network [OSTI]

The Large Hadron Collider (LHC) at CERN in Geneva (Switzerland) will go in operation in the coming months and will soon enable us to analyze the highest energy collisions ever produced at an accelerator. Beyond Standard Model searches at LHC require a detailed understanding of the detector performance, reconstruction algorithms and triggering. Precision measurements of Standard Model processes are also mandatory to acquire the necessary knowledge of Standard Model background. Both ATLAS and CMS efforts are hence addressed to determine the best calibration candles and to design a realistic plan for the initial period of data taking.

S. Beauceron

2008-08-27T23:59:59.000Z

137

Comparative Metabolism of Carbon Tetrachloride in Rats, Mice and Hamsters Using Gas Uptake and PBPK Modeling  

SciTech Connect (OSTI)

No study has comprehensively compared the rate of metabolism of carbon tetrachloride (CCl4) across species. Therefore, the in vivo metabolism of CCl4 was evaluated using groups of male animals (F344 rats, B6C3F1 mice, and Syrian hamsters) exposed to 40-1800 ppm CCl4 in a closed, recirculating gas-uptake system. For each species, an optimal fit of the family of uptake curves was obtained by adjusting Michaelis-Menten metabolic constants Km (affinity) and Vmax (capacity) using a physiologically based pharmacokinetic (PBPK) model. The results show that the mouse has a slightly higher capacity and lower affinity for metabolizing CCl4 compared to the rat, while the hamster has a higher capacity and lower affinity than either rat or mouse. A comparison of the Vmax to Km ratio, normalized for mg of liver protein (L/hr/mg) across species indicates that hamsters metabolize more CCl4 than either rats or mice, and should be more susceptible to CCl4-induced hepatotoxicity. These species comparisons were evaluated against toxicokinetic studies conducted in animals exposed by nose-only inhalation to 20 ppm 14C-labeled CCl4 for 4 hours. The toxicokinetic study results are consistent with the in vivo rates of metabolism, with rats eliminating less radioactivity associated with metabolism (14CO2 and urine/feces) and more radioactivity associated with the parent compound (radioactivity trapped on charcoal) compared to either hamsters or mice. The in vivo metabolic constants determined here, together with in vitro constants determined using rat, mouse, hamster and human liver microsomes, were used to estimate human in vivo metabolic rates of 1.49 mg/hr/kg body weight and 0.25 mg/L for Vmax and Km, respectively. Normalizing the rate of metabolism (Vmax/Km) by mg liver protein, the rate of metabolism of CCl4 differs across species, with hamster > mouse& > rat > human.

Thrall, Karla D. (BATTELLE (PACIFIC NW LAB)); Vucelick, Mark E. (FLUOR HANFORD, INC); Gies, Richard A. (BATTELLE (PACIFIC NW LAB)); Zangar, Richard C. (BATTELLE (PACIFIC NW LAB)); Weitz, Karl K. (BATTELLE (PACIFIC NW LAB)); Poet, Torka S. (BATTELLE (PACIFIC NW LAB)); Springer, David L. (BATTELLE (PACIFIC NW LAB)); Grant, Donna M. (BATTELLE (PACIFIC NW LAB)); Benson, Janet M. (Inhalation Toxicology Research Institute)

2000-08-25T23:59:59.000Z

138

MECHANICAL MODELING OF GLASS AND CARBON EPOXY COMPOSITES Barzin Mobasher 1  

E-Print Network [OSTI]

MECHANICAL MODELING OF GLASS AND CARBON EPOXY COMPOSITES Barzin Mobasher 1 , Associate Member ASCE and flexural loading. INTRODUCTION In order to commercially utilize new composite materials in civil of composite laminates. The proposed methodology can be used as a new composite material or used

Mobasher, Barzin

139

Seismic modelling of a fractured carbonate reservoir in Abu Dhabi, United Arab Emirates  

E-Print Network [OSTI]

Seismic modelling of a fractured carbonate reservoir in Abu Dhabi, United Arab Emirates Mohammed Y is required to optimize hydrocarbon production. A rock containing parallel fractures can be seismically to the seismic wavelength. Seismic anisotropy may be detectable from attributes of pre-stack 3-D seismic data

Ali, Mohammed

140

Carbon pools in Mediterranean forests: comparing eddy covariance and GOTILWA+ model results.  

E-Print Network [OSTI]

of water stress on ecosystem function leads to big discrepancies when modelling under these conditions. Recent advances allow us to successfully reproduce water and carbon balances during periods of stress ilex, Pinus ponderosa, and Fagus sylvatica, and varying degrees of water stress and ecosystem responses

Gracia, Carlos

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141

Comparison of multivariate methods for inferential modeling of soil carbon using visible/near-infrared spectra  

E-Print Network [OSTI]

Comparison of multivariate methods for inferential modeling of soil carbon using visible/near-infrared Diffuse reflectance spectroscopy Visible/near-infrared spectroscopy Multivariate calibration Pre-processing transformations In order to reduce costs and time in the analysis of soil properties, visible/near-infrared

Grunwald, Sabine

142

Multiphysics modeling of carbon gasification processes in a well-stirred reactor with detailed gas-phase chemistry  

E-Print Network [OSTI]

Multiphysics modeling of carbon gasification processes in a well-stirred reactor with detailed gas: Coal gasification Carbon gasification Detailed chemistry Heterogeneous surface reactions Radiation Multi-physics numerical modeling a b s t r a c t Fuel synthesis through coal and biomass gasification

Qiao, Li

143

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.

144

The Impact of Carbon Pricing on Wholesale Electricity Prices, Carbon Pass-Through Rates and Retail Electricity Tariffs in Australia.1  

E-Print Network [OSTI]

1 The Impact of Carbon Pricing on Wholesale Electricity Prices, Carbon Pass-Through Rates that the introduction of a carbon price signal will have on wholesale electricity prices, carbon-pass-through rates is used to determine optimal dispatch of generation plant and wholesale prices within the ANEM model. We

Tesfatsion, Leigh

145

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

SciTech Connect (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

146

Kinetic models for uncatalyzed and potassium-catalyzed gasification of char by carbon dioxide  

SciTech Connect (OSTI)

A differential packed-bed reactor has been employed to study the gasification of uncatalyzed and 7.5 wt% K/sub 2/CO/sub 3/-catalyzed Saran char in carbon dioxide/carbon monoxide mixtures at a total pressure near 1 atm (101.3 kPa). The gasification temperature was varied between 1131 and 1229 K for the uncatalyzed case, and between 922 and 1046 K for the catalyzed case. Gasification rate data were tested with a model which involves two-site adsorption and subsequent dissociation of CO/sub 2/ on the char surface. The results indicate that this model adequately explains both the uncatalyzed and catalyzed gasification data. However, higher concentrations of carbon-oxygen complex, (C(O)), exist on the surface during catalyzed gasification. The increase in (C(O)) weakens carbon-carbon bonds and thus lowers the activation energy for desorption of the C(O) complex. Adsorption of CO and CO/sub 2/ on both catalyzed and uncatalyzed chars was also followed with a volumetric adsorption apparatus at pressures between 1 and 100 kPa and temperatures from 273 to 725 K. The catalyzed char adsorbed an order of magnitude more CO/sub 2/ at 559 K than the uncatalyzed char. Subsequent dissociation of CO/sub 2/ on the carbon surface does not appear to be catalyzed by potassium. Thus, the catalysts' role is to augment the efficiency and/or number of sites for CO/sub 2/ adsorption, thereby creating more oxygen on the surface. The higher rate during catalyzed gasification can be attributed to a combination of increased (C(O)) and a smaller activation energy for desorption of C(O).

Koenig, P.C.

1985-01-01T23:59:59.000Z

147

Low Cost Carbon Fibre: Applications, Performance and Cost Models - Chapter 17  

SciTech Connect (OSTI)

Weight saving in automotive applications has a major bearing on fuel economy. It is generally accepted that, typically, a 10% weight reduction in an automobile will lead to a 6-8% improvement in fuel economy. In this respect, carbon fibre composites are extremely attractive in their ability to provide superlative mechanical performance per unit weight. That is why they are specified for high-end uses such as Formula 1 racing cars and the latest aircraft (e.g. Boeing 787, Airbus A350 and A380), where they comprise over 50% by weight of the structure However, carbon fibres are expensive and this renders their composites similarly expensive. Research has been carried out at Oak Ridge National Laboratories (ORNL), Tennessee, USA for over a decade with the aim of reducing the cost of carbon fibre such that it becomes a cost-effective option for the automotive industry. Aspects of this research relating to the development of low cost carbon fibre have been reported in Chapter 3 of this publication. In this chapter, the practical industrial applications of low-cost carbon fibre are presented, together with considerations of the performance and cost models which underpin the work.

Warren, Charles David [ORNL; Wheatley, Dr. Alan [University of Sunderland; Das, Sujit [ORNL

2014-01-01T23:59:59.000Z

148

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

SciTech Connect (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 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

149

The North American Carbon Program Multi-scale synthesis and Terrestrial Model Intercomparison Project Part 1: Overview and experimental design  

SciTech Connect (OSTI)

Terrestrial biosphere models (TBMs) have become an integral tool for extrapolating local observations and understanding of land-atmosphere carbon exchange to larger regions. The North American Carbon Program (NACP) Multi-scale synthesis and Terrestrial Model Intercomparison Project (MsTMIP) is a formal model intercomparison and evaluation effort focused on improving the diagnosis and attribution of carbon exchange at regional and global scales. MsTMIP builds upon current and past synthesis activities, and has a unique framework designed to isolate, interpret, and inform understanding of how model structural differences impact estimates of carbon uptake and release. Here we provide an overview of the MsTMIP effort and describe how the MsTMIP experimental design enables the assessment and quantification of TBM structural uncertainty. Model structure refers to the types of processes considered (e.g. nutrient cycling, disturbance, lateral transport of carbon), and how these processes are represented (e.g. photosynthetic formulation, temperature sensitivity, respiration) in the models. By prescribing a common experimental protocol with standard spin-up procedures and driver data sets, we isolate any biases and variability in TBM estimates of regional and global carbon budgets resulting from differences in the models themselves (i.e. model structure) and model-specific parameter values. An initial intercomparison of model structural differences is represented using hierarchical cluster diagrams (a.k.a. dendrograms), which highlight similarities and differences in how models account for carbon cycle, vegetation, energy, and nitrogen cycle dynamics. We show that, despite the standardized protocol used to derive initial conditions, models show a high degree of variation for GPP, total living biomass, and total soil carbon, underscoring the influence of differences in model structure and parameterization on model estimates.

Huntzinger, D.N. [Northern Arizona University] [Northern Arizona University; Schwalm, C. [Northern Arizona University] [Northern Arizona University; Michalak, A.M [Carnegie Institution for Science, Stanford] [Carnegie Institution for Science, Stanford; Schaefer, K. [National Snow and Ice Data Center] [National Snow and Ice Data Center; King, A.W. [Oak Ridge National Laboratory (ORNL)] [Oak Ridge National Laboratory (ORNL); Wei, Y. [Oak Ridge National Laboratory (ORNL)] [Oak Ridge National Laboratory (ORNL); Jacobson, A. [National Snow and Ice Data Center] [National Snow and Ice Data Center; Liu, S. [Oak Ridge National Laboratory (ORNL)] [Oak Ridge National Laboratory (ORNL); Cook, R. [Oak Ridge National Laboratory (ORNL)] [Oak Ridge National Laboratory (ORNL); Post, W.M. [Oak Ridge National Laboratory (ORNL)] [Oak Ridge National Laboratory (ORNL); Berthier, G. [Laboratoire des Sciences du Climat et de l'Environnement (LSCE)] [Laboratoire des Sciences du Climat et de l'Environnement (LSCE); Hayes, D. [Oak Ridge National Laboratory (ORNL)] [Oak Ridge National Laboratory (ORNL); Huang, M. [Pacific Northwest National Laboratory (PNNL)] [Pacific Northwest National Laboratory (PNNL); Ito, A. [National Institute for Environmental Studies, Tsukuba, Japan] [National Institute for Environmental Studies, Tsukuba, Japan; Lei, H. [Pacific Northwest National Laboratory (PNNL)] [Pacific Northwest National Laboratory (PNNL); Lu, C. [International Center for Climate and Global Change Research and School of Forestry and Wildlife Sci.] [International Center for Climate and Global Change Research and School of Forestry and Wildlife Sci.; Mao, J. [Oak Ridge National Laboratory (ORNL)] [Oak Ridge National Laboratory (ORNL); Peng, C.H. [University of Quebec at Montreal, Institute of Environment Sciences] [University of Quebec at Montreal, Institute of Environment Sciences; Peng, S. [Laboratoire des Sciences du Climat et de l'Environnement (LSCE)] [Laboratoire des Sciences du Climat et de l'Environnement (LSCE); Poulter, B. [Laboratoire des Sciences du Climat et de l'Environnement (LSCE)] [Laboratoire des Sciences du Climat et de l'Environnement (LSCE); Riccuito, D. [Oak Ridge National Laboratory (ORNL)] [Oak Ridge National Laboratory (ORNL); Shi, X. [Oak Ridge National Laboratory (ORNL)] [Oak Ridge National Laboratory (ORNL); Tian, H. [International Center for Climate and Global Change Research and School of Forestry and Wildlife Sci.] [International Center for Climate and Global Change Research and School of Forestry and Wildlife Sci.; Wang, W. [National Aeronautics and Space Administration (NASA), Ames Research Center, Moffett Field] [National Aeronautics and Space Administration (NASA), Ames Research Center, Moffett Field; Zeng, N. [University of Maryland] [University of Maryland; Zhao, F. [University of Maryland] [University of Maryland; Zhu, Q. [Laboratory for Ecological Forecasting and Northwest Agriculture and Forestry University] [Laboratory for Ecological Forecasting and Northwest Agriculture and Forestry University

2013-01-01T23:59:59.000Z

150

Modeling the water-carbon-energy cycle | EMSL  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr May JunDatastreamsmmcrcalgovInstrumentsrucLas Conchas recovery challenge fundProject8Mistakes to Avoid MistakesResponse Times.Modeling

151

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

152

Model comparisons for estimating carbon emissions from North American wildland fire  

E-Print Network [OSTI]

Hirsch (2001), Direct carbon emissions from Canadian forestin estimating carbon emissions from boreal forest fires, J.Law (2007), Pyrogenic carbon emission from a large wildfire

2011-01-01T23:59:59.000Z

153

Optimization of carbon capture systems using surrogate models of simulated processes.  

SciTech Connect (OSTI)

With increasing demand placed on power generation plants to reduce carbon dioxide (CO2) emissions, processes to separate and capture CO2 for eventual sequestration are highly sought after. Carbon capture processes impart a parasitic load on the power plants; it is estimated that this would increase the cost of electricity from existing pulverized coal plants anywhere from 71-85 percent [1]. The National Energy and Technology Lab (NETL) is working to lower this to below a 30 percent increase. To reach this goal, work is being done not only to accurately simulate these processes, but also to leverage those accurate and detailed simulations to design optimal carbon capture processes. The major challenges include the lack of accurate algebraic models of the processes, computationally costly simulations, and insufficiently robust simulations. The first challenge bars the use of provable derivative-based optimization algorithms. The latter two can either lead to difficult or impossible direct derivative-free optimization. To overcome these difficulties, we take a more indirect method to solving this problem by, first, generating an accurate set of algebraic surrogate models from the simulation then using derivative-based solvers to optimize the surrogate models. We developed a method that uses derivative-based and derivative-free optimization alongside machine learning and statistical techniques to generate the set of low-complexity surrogate models using data sampled from detailed simulations. The models are validated and improved through the use of derivative-free solvers to adaptively sample new simulation points. The resulting surrogate models can then be used in a superstructure-based process synthesis and solved using derivative-based methods to optimize carbon capture processes.

Cozad, A.; Chang, Y.; Sahinidis, N.; Miller, D.

2011-01-01T23:59:59.000Z

154

A Three-Dimensional Ocean-Seaice-Carbon Cycle Model and its Coupling to a Two-Dimensional Atmospheric Model: Uses in Climate Change Studies  

E-Print Network [OSTI]

We describe the coupling of a three-dimensional ocean circulation model, with explicit thermodynamic seaice and ocean carbon cycle representations, to a two-dimensional atmospheric/land model. This coupled system has been ...

Dutkiewicz, Stephanie.

155

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

SciTech Connect (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 temperatures in the range of 50C to 100C 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

156

Exploration model for shallow Silurian (Kankakee) carbonate reservoirs in western Illinois  

SciTech Connect (OSTI)

Reservoirs in shallow (600-650 ft deep) basal Silurian Kankakee carbonates at Buckhorn consolidated, Siloam, and Kellerville oil fields in western Illinois have produced nearly 2 million bbl of oil, but were developed essentially by random drilling. A new exploration model that combines lithologic studies and isopach mapping has been developed at the Illinois State Geological Survey. Isopach mapping of Silurian and Devonian rocks between an organic facies in the Mississippian-Devonian New Albany Shale and the top of the Ordovician Maquoketa Shale reveals thickened sequences that coincide with most of the oil fields. These thickened intervals apparently reflect subtle paleovalleys eroded into the Maquoketa shale during the Ordovician-Silurian hiatus. During the initial Silurian marine transgression, these paleovalleys at the base of the Kankakee were filled with carbonates to form the thickened sequences. Differential erosion at the top of the Kankakee does not satisfactorily explain the locally thickened sequences in the Kankakee. Lithologic studies suggest that subsurface fluid flows concentrated along these paleovalleys contributed to subsequent diagenesis of valleyfill carbonates. Diagenetic alteration of these carbonates resulted in development of basal Kankakee reservoirs within the paleovalleys. This concept of Kankakee reservoirs occurring within paleovalleys at the Ordovician-Silurian unconformity is a new exploration model that can aid in the search for similar traps in western Illinois.

Crockett, J.E.; Seyler, B.J.; Whitaker, S.

1987-09-01T23:59:59.000Z

157

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

158

The Carbon-Land Model Intercomparison Project (C-LAMP): A Model-Data Comparison System for Evaluation of Coupled Biosphere-Atmosphere Models  

SciTech Connect (OSTI)

The need to capture important climate feebacks in general circulation models (GCMs) has resulted in new efforts to include atmospheric chemistry and land and ocean biogeochemistry into the next generation of production climate models, now often referred to as Earth System Models (ESMs). While many terrestrial and ocean carbon models have been coupled to GCMs, recent work has shown that such models can yield a wide range of results, suggesting that a more rigorous set of offline and partially coupled experiments, along with detailed analyses of processes and comparisons with measurements, are warranted. The Carbon-Land Model Intercomparison Project (C-LAMP) provides a simulation protocol and model performance metrics based upon comparisons against best-available satellite- and ground-based measurements (Hoffman et al., 2007). C-LAMP provides feedback to the modeling community regarding model improvements and to the measurement community by suggesting new observational campaigns. C-LAMP Experiment 1 consists of a set of uncoupled simulations of terrestrial carbon models specifically designed to examine the ability of the models to reproduce surface carbon and energy fluxes at multiple sites and to exhibit the influence of climate variability, prescribed atmospheric carbon dioxide (CO{sub 2}), nitrogen (N) deposition, and land cover change on projections of terrestrial carbon fluxes during the 20th century. Experiment 2 consists of partially coupled simulations of the terrestrial carbon model with an active atmosphere model exchanging energy and moisture fluxes. In all experiments, atmospheric CO{sub 2} follows the prescribed historical trajectory from C{sup 4}MIP. In Experiment 2, the atmosphere model is forced with prescribed sea surface temperatures (SSTs) and corresponding sea ice concentrations from the Hadley Centre; prescribed CO{sub 2} is radiatively active; and land, fossil fuel, and ocean CO{sub 2} fluxes are advected by the model. Both sets of experiments have been performed using two different terrestrial biogeochemistry modules coupled to the Community Land Model version 3 (CLM3) in the Community Climate System Model version 3 (CCSM3): The CASA model of Fung, et al., and the carbon-nitrogen (CN) model of Thornton. Comparisons against Ameriflus site measurements, MODIS satellite observations, NOAA flask records, TRANSCOM inversions, and Free Air CO{sub 2} Enrichment (FACE) site measurements, and other datasets have been performed and are described in Randerson et al. (2009). The C-LAMP diagnostics package was used to validate improvements to CASA and CN for use in the next generation model, CLM4. It is hoped that this effort will serve as a prototype for an international carbon-cycle model benchmarking activity for models being used for the Inter-governmental Panel on Climate Change (IPCC) Fifth Assessment Report. More information about C-LAMP, the experimental protocol, performance metrics, output standards, and model-data comparisons from the CLM3-CASA and CLM3-CN models are available at http://www.climatemodeling.org/c-lamp.

Hoffman, Forrest M [ORNL; Randerson, Jim [University of California, Irvine; Thornton, Peter E [ORNL; Mahowald, Natalie [Cornell University; Bonan, Gordon [National Center for Atmospheric Research (NCAR); Running, Steven [University of Montana, Missoula; Fung, Inez [University of California, Berkeley

2009-01-01T23:59:59.000Z

159

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-

160

Results from the Carbon-Land Model Intercomparison Project (C-LAMP) and Availability of the Data on the Earth System Grid (ESG)  

SciTech Connect (OSTI)

This paper describes the Carbon-Land Model Intercomparison Project (C-LAMP) being carried out through a collaboration between the Community Climate System Model (CCSM) Biogeochemistry Working Group, a DOE SciDAC-2 project, and the DOE Program for Climate Model Diagnosis and Intercomparison (PCMDI). The goal of the project is to intercompare terrestrial biogeochemistry models running within the CCSM framework to determine the best set of processes to include in future versions of CCSM. As a part of the project, observational datasets are being collected and used to score the scientific performance of these models following a well-defined set of metrics. In addition, metadata standards for terrestrial biosphere models are being developed to support archival and distribution of the C-LAMP model output via the Earth System Grid (ESG). Progress toward completion of this project and preliminary results from the first set of experiments are reported.

Hoffman, Forrest M [ORNL; Covey, Curtis [Lawrence Livermore National Laboratory (LLNL); Fung, Inez [University of California, Berkeley; Randerson, Jim [University of California, Irvine; Thornton, Peter [National Center for Atmospheric Research (NCAR); Lee, Jeff [National Center for Atmospheric Research (NCAR); Rosenbloom, Nan [National Center for Atmospheric Research (NCAR); Stockli, Reto [Colorado State University, Fort Collins; Running, Steven [University of Montana, Missoula; Bernholdt, David E [ORNL; Williams, Dean [Lawrence Livermore National Laboratory (LLNL)

2007-01-01T23:59:59.000Z

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.


161

Modeling Electrochemical Decomposition of Fluoroethylene Carbonate on Silicon Anode Surfaces in Lithium Ion Batteries  

E-Print Network [OSTI]

Fluoroethylene carbonate (FEC) shows promise as an electrolyte additive for improving passivating solid-electrolyte interphase (SEI) films on silicon anodes used in lithium ion batteries (LIB). We apply density functional theory (DFT), ab initio molecular dynamics (AIMD), and quantum chemistry techniques to examine excess-electron-induced FEC molecular decomposition mechanisms that lead to FEC-modified SEI. We consider one- and two-electron reactions using cluster models and explicit interfaces between liquid electrolyte and model Li(x)Si(y) surfaces, respectively. FEC is found to exhibit more varied reaction pathways than unsubstituted ethylene carbonate. The initial bond-breaking events and products of one- and two-electron reactions are qualitatively similar, with a fluoride ion detached in both cases. However, most one-electron products are charge-neutral, not anionic, and may not coalesce to form effective Li+-conducting SEI unless they are further reduced or take part in other reactions. The implication...

Leung, Kevin; Foster, Michael E; Ma, Yuguang; del la Hoz, Julibeth M Martinez; Sai, Na; Balbuena, Perla B

2014-01-01T23:59:59.000Z

162

The surface carbon and nitrogen abundances in models of ultra metal-poor stars  

E-Print Network [OSTI]

We investigate whether the observed high number of carbon- and nitrogen-enhanced extremely metal-poor stars could be explained by peculiar evolutionary properties during the core He flash at the tip of the red giant branch. For this purpose we compute a series of detailed stellar models expanding upon our previous work; in particular, we investigate if during the major He flash the penetration of the helium convective zone into the overlying hydrogen-rich layers can produce carbon- and nitrogen-rich abundances in agreement with current spectroscopic observations. The dependence of this phenomenon on selected model input parameters, such as initial metallicity and treatment of convection is examined in detail.

H. Schlattl; M. Salaris; S. Cassisi; A. Weiss

2002-05-20T23:59:59.000Z

163

Carbon dioxide, argon, nitrogen and methane clathrate hydrates:1 thermodynamic modelling, investigation of their stability in Martian2  

E-Print Network [OSTI]

1 Carbon dioxide, argon, nitrogen and methane clathrate hydrates:1 thermodynamic modelling-4Dec2012 #12;3 Keywords: Mars, clathrate hydrate, nitrogen, carbon dioxide, argon, methane, equilibrium and allows to simulating a Martian gas, CO2 dominated (95.3%) plus nitrogen6 (2.7%) and argon (2

Paris-Sud XI, Université de

164

Calculating the Social Cost of Carbon  

E-Print Network [OSTI]

The paper1 discusses the determination of the social cost of carbon (SCC) using the PAGE2002 model used in the Stern Review. The SCC depends sensitively on assumptions about future economic development, the range and likelihood of economic...

Hope, Chris; Newbery, David

165

Soil Carbon Change and Net Energy Associated with Biofuel Production on Marginal Lands: A Regional Modeling Perspective  

SciTech Connect (OSTI)

The use of marginal lands (MLs) for biofuel production has been contemplated as a promising solution for meeting biofuel demands. However, there have been concerns with spatial location of MLs, their inherent biofuel potential, and possible environmental consequences with the cultivation of energy crops. Here, we developed a new quantitative approach that integrates high-resolution land cover and land productivity maps and uses conditional probability density functions for analyzing land use patterns as a function of land productivity to classify the agricultural lands. We subsequently applied this method to determine available productive croplands (P-CLs) and non-crop marginal lands (NC-MLs) in a nine-county Southern Michigan. Furthermore, Spatially Explicit Integrated Modeling Framework (SEIMF) using EPIC (Environmental Policy Integrated Climate) was used to understand the net energy (NE) and soil organic carbon (SOC) implications of cultivating different annual and perennial production systems.

Bandaru, Varaprasad; Izaurralde, Roberto C.; Manowitz, David H.; Link, Robert P.; Zhang, Xuesong; Post, W. M.

2013-12-01T23:59:59.000Z

166

A comparison of alumina, carbon, and carbon-covered alumina as supports for Ni-Mo-F additives: Carbon deposition and model compound reaction studies  

SciTech Connect (OSTI)

Fluoride-promoted Ni-Mo catalysts supported on alumina, carbon, and carbon-coveres alumina have been investigated for their activity in cumene cracking, hydrocracking (reduced and sulfided forms), and thiophene HDS. The carbon-covered alumina was prepared by pyrolysis of cyclohexene over either {gamma}-alumina or boehmite and the carbon deposition followed adsorption isotherm-type behavior. The cumene reaction studies indicate that the resulting support system successfully merges the properties of carbon and alumina, possessing improved dehydrogenation-hydrogenation functionality due to carbon and acidic properties due to alumina, such as the generation of Broensted acidity upon fluoride impregnation. In the thiophene HDS reaction the catalyst activities followed the order Al{sub 2} > C-Al{sub 2}O{sub 3} > C, suggesting that alumina, and not carbon, is the superior HDS support at atmospheric H{sub 2} pressure and at the metal loadings used in this study. Carbon deposition onto Ni-Mo-F/Al{sub 2}O{sub 3} catalysts revealed that cyclohexene polymerization is promoted by the metal centers, resulting in multilayer islands on these sites, and not by the fluoride-associated Broensted acid sites. However, the Broensted acid sites do promote coke formation when the polymerization reaction is easier such as for {alpha}-methylstyrene.

Boorman, P.M.; Chong, K.; Kydd, R.A.; Lewis, J.M. (Univ. of Calgary, Alberta (Canada))

1991-04-01T23:59:59.000Z

167

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

SciTech Connect (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

168

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

SciTech Connect (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

169

Causes and Implications of Persistent Atmospheric Carbon Dioxide Biases in Earth System Models  

SciTech Connect (OSTI)

The strength of feedbacks between a changing climate and future CO2 concentrations are uncertain and difficult to predict using Earth System Models (ESMs). We analyzed emission-driven simulations--in which atmospheric CO2 levels were computed prognostically--for historical (1850-2005) and future periods (RCP 8.5 for 2006-2100) produced by 15 ESMs for the Fifth Phase of the Coupled Model Intercomparison Project (CMIP5). Comparison of ESM prognostic atmospheric CO2 over the historical period with observations indicated that ESMs, on average, had a small positive bias in predictions of contemporary atmospheric CO2. Weak ocean carbon uptake in many ESMs contributed to this bias, based on comparisons with observations of ocean and atmospheric anthropogenic carbon inventories. We found a significant linear relationship between contemporary atmospheric CO2 biases and future CO2 levels for the multi-model ensemble. We used this relationship to create a contemporary CO2 tuned model (CCTM) estimate of the atmospheric CO2 trajectory for the 21st century. The CCTM yielded CO2 estimates of 600 {plus minus} 14 ppm at 2060 and 947 {plus minus} 35 ppm at 2100, which were 21 ppm and 32 ppm below the multi-model mean during these two time periods. Using this emergent constraint approach, the likely ranges of future atmospheric CO2, CO2-induced radiative forcing, and CO2-induced temperature increases for the RCP 8.5 scenario were considerably narrowed compared to estimates from the full ESM ensemble. Our analysis provided evidence that much of the model-to-model variation in projected CO2 during the 21st century was tied to biases that existed during the observational era, and that model differences in the representation of concentration-carbon feedbacks and other slowly changing carbon cycle processes appear to be the primary driver of this variability. By improving models to more closely match the long-term time series of CO2 from Mauna Loa, our analysis suggests uncertainties in future climate projections can be reduced.

Hoffman, Forrest M [ORNL] [ORNL; Randerson, James T. [University of California, Irvine] [University of California, Irvine; Arora, Vivek K. [Canadian Centre for Climate Modelling and Analysis, Meteorological Service of Canada] [Canadian Centre for Climate Modelling and Analysis, Meteorological Service of Canada; Bao, Qing [State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics] [State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics; Cadule, Patricia [Institut Pierre Simon Laplace, Laboratoire des Sciences du Climat et de l'Environment] [Institut Pierre Simon Laplace, Laboratoire des Sciences du Climat et de l'Environment; Ji, Duoying [State Key Laboratory of Earth Surface Processes and Resource Ecology, Beijing] [State Key Laboratory of Earth Surface Processes and Resource Ecology, Beijing; Jones, Chris D. [Hadley Centre, U.K. Met Office] [Hadley Centre, U.K. Met Office; Kawamiya, Michio [Japan Agency for Marine-Earth Science and Technology (JAMSTEC)] [Japan Agency for Marine-Earth Science and Technology (JAMSTEC); Khatiwala, Samar [Lamont-Doherty Earth Observatory, Columbia University, Palisades, NY] [Lamont-Doherty Earth Observatory, Columbia University, Palisades, NY; Lindsay, Keith [National Center for Atmospheric Research (NCAR)] [National Center for Atmospheric Research (NCAR); Obata, Atsushi [Meteorological Research Institute, Japan] [Meteorological Research Institute, Japan; Shevliakova, Elena [Princeton University] [Princeton University; Six, Katharina D. [Max Planck Institute for Meteorology, Hamburg, Germany] [Max Planck Institute for Meteorology, Hamburg, Germany; Tjiputra, Jerry F. [Uni Climate, Uni Research] [Uni Climate, Uni Research; Volodin, Evgeny M. [Institute of Numerical Mathematics, Russian Academy of Science, Moscow] [Institute of Numerical Mathematics, Russian Academy of Science, Moscow; Wu, Tongwen [China Meteorological Administration (CMA), Beijing] [China Meteorological Administration (CMA), Beijing

2014-01-01T23:59:59.000Z

170

Climate Determinism Revisited: Multiple Equilibria in a Complex Climate Model  

E-Print Network [OSTI]

Multiple equilibria in a coupled oceanatmospheresea 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

171

Benchmarking GEANT4 nuclear models for hadron therapy with 95 MeV/nucleon carbon ions  

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

2014-05-30T23:59:59.000Z

172

Model for corrosion of carbon steel in lithium bromide absorption refrigeration systems  

SciTech Connect (OSTI)

A comprehensive model has been developed for the computation of corrosion rates of carbon steels in the presence of lithium bromide (LiBr)-based brines that are used as working fluids for absorption refrigeration cycles. The model combines a thermophysical module that provides realistic speciation of aqueous systems with an electrochemical module for partial cathodic and anodic processes on the metal surface. The electrochemical module includes the absorption of halides, which strongly influences the corrosion process. Also, the model takes into account the formation of passive films and their interactions with solution species. The model has been verified by comparing calculated corrosion rates with laboratory data for carbon steels in LiBr solutions. Good agreement between calculated and experimental corrosion rates has been obtained. In particular, the model is capable of reproducing effects of pH-adjusting components and selected inhibitors on the rates of general corrosion. The model has been incorporated into a program that makes it possible to analyze effects of various conditions such as temperature, pressure, solution composition, or flow velocity on corrosion rates.

Anderko, A.; Young, R.D.

2000-05-01T23:59:59.000Z

173

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

SciTech Connect (OSTI)

We have developed a framework for assessing the leakage risk of geologic carbon sequestration sites. This framework, known as the Certification Framework (CF), emphasizes wells and faults as the primary potential leakage conduits. Vulnerable resources are grouped into compartments, and impacts due to leakage are quantified by the leakage flux or concentrations that could potentially occur in compartments under various scenarios. The CF utilizes several model components to simulate leakage scenarios. One model component is a catalog of results of reservoir simulations that can be queried to estimate plume travel distances and times, rather than requiring CF users to run new reservoir simulations for each case. Other model components developed for the CF and described here include fault characterization using fault-population statistics; fault connection probability using fuzzy rules; well-flow modeling with a drift-flux model implemented in TOUGH2; and atmospheric dense-gas dispersion using a mesoscale weather prediction code.

Oldenburg, Curtis M.; Bryant, Steven L.; Nicot, Jean-Philippe; Kumar, Navanit; Zhang, Yingqi; Jordan, Preston; Pan, Lehua; Granvold, Patrick; Chow, Fotini K.

2009-06-01T23:59:59.000Z

174

Extinction properties of single-walled carbon nanotubes: Two-fluid model  

SciTech Connect (OSTI)

The extinction spectra of a single-walled carbon nanotube are investigated, within the framework of the vector wave function method in conjunction with the hydrodynamic model. Both polarizations of the incident plane wave (TE and TM with respect to the x-z plane) are treated. Electronic excitations on the nanotube surface are modeled by an infinitesimally thin layer of a two-dimensional electron gas represented by two interacting fluids, which takes into account the different nature of the ? and ? electrons. Numerical results show that strong interaction between the fluids gives rise to the splitting of the extinction spectra into two peaks in quantitative agreement with the ? and ? + ? plasmon energies.

Moradi, Afshin, E-mail: a.moradi@kut.ac.ir [Department of Basic Sciences, Kermanshah University of Technology, Kermanshah, Iran and Department of Nano Science, Institute for Studies in Theoretical Physics and Mathematics (IPM), Tehran (Iran, Islamic Republic of)] [Department of Basic Sciences, Kermanshah University of Technology, Kermanshah, Iran and Department of Nano Science, Institute for Studies in Theoretical Physics and Mathematics (IPM), Tehran (Iran, Islamic Republic of)

2014-03-15T23:59:59.000Z

175

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.

176

Model Development Development of a system emulating the global carbon cycle in Earth system models  

E-Print Network [OSTI]

developed a loosely coupled model (LCM) which can represent the outputs of a GCMbased Earth system model

K. Tachiiri; J. C. Hargreaves; J. D. Annan; A. Oka; A. Abe-ouchi; M. Kawamiya

2010-01-01T23:59:59.000Z

177

A parametric study of factors affecting oil recovery efficiency from carbon dioxide injection using a compositional reservoir model  

E-Print Network [OSTI]

Factors Affecting Oil Recovery Estimating Oil Recovery From Carbon Dioxide Flooding 15 33 CHAPTER III ? FIELD CASE ANALYSIS 38 3. 1 3. 2 3. 3 3. 4 Background Laboratory Analysis Reservoir Analysis Estimates of Injection Recovery and Project... to estimate the recovery of oil from continuous injection of carbon dioxide. Finally, the results of the sensitivity analysis were compared to published laboratory and theoretical models and documented field results to test the correlation model. CHAPTER...

Barnes, Gregory Allen.

1991-01-01T23:59:59.000Z

178

Application of computer modeling techniques to the kinetics of the reaction of carbon with oxygen  

SciTech Connect (OSTI)

Computer modeling techniques are applied to the kinetics of the reaction of carbon with oxygen. The rates of disappearance of oxygen, of formation of CO, CO/sub 2/ and the surface complex, measured over the temperature range 748-1173 K and the pressure range 0.5-400 Pa may be described by a mechanism involving adsorption of oxygen, formation of the strongly-bound complex, desorption of the complex and reaction of the complex with a gas-phase molecule of oxygen. The latter is shown to be an important source of CO/sub 2/ at low temperatures and higher pressures of oxygen. An important feature of the mechanism is the existence of at least two distinct types of active sites for the binding of the complex on the carbon surface, each with a characteristic reactivity. Most of the results on which the model is based were obtained using thin films of pyrolytic carbon, but some results from the oxidation of graphon are also consistent with the mechanism.

Ahmed, S.; Back, M.H.; Roscoe, J.M.

1989-01-01T23:59:59.000Z

179

Climate determinism revisited: multiple equilibria in a complex climate model  

E-Print Network [OSTI]

by incoming solar radiation at the top of the atmosphere. We demonstrate that the multiple equilibria owe `snowball' state. Although low-order energy balance models of the climate are known to exhibit-640 Ma ago, e.g. Hoffmann et al. 1998), to a warm-house (no-ice) in the Cretaceous (e.g. Zachos et al

Marshall, John

180

Determining Sources of Dissolved Organic Carbon and Nutrients in an Urban Basin Using Novel and Traditional Methods  

E-Print Network [OSTI]

Water quality in urban ecosystems is sensitive to localized disturbances potentially affecting those mechanisms which influence nutrient cycles. The Carters Creek Basin has been reported to have elevated concentrations of dissolved organic carbon...

Govil, Krittika

2014-01-03T23:59:59.000Z

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

Selective Detection of Ethylene Gas Using Carbon Nanotube-based Devices: Utility in Determination of Fruit Ripeness  

E-Print Network [OSTI]

Comparing apples and oranges: A chemoresistive sensor for ethylene can be obtained simply by mixing copper complex 1 with single-walled carbon nanotubes. The resulting devices show sub-ppm sensitivity and high selectivity ...

Swager, Timothy Manning

182

Can reductions in logging damage increase carbon storage over time? Evaluation of a simulation model for a pilot carbon offset project in Malaysia  

SciTech Connect (OSTI)

Selective timber harvesting operations, if uncontrolled, can severely degrade a forest. Although techniques for reducing logging damage are well-known and inexpensive to apply, incentives to adopt these techniques are generally lacking. Power companies and other emitters of {open_quotes}greenhouse{close_quotes} gases soon may be forced to reduce or otherwise offset their net emissions; one offset option is to fund programs aimed at reducing logging damage. To investigate the consequences of reductions in logging damage for ecosystem carbon storage, I constructed a model to simulate changes in biomass and carbon pools following logging of primary dipterocarp forests in southeast Asia. I adapted a physiologically-driven, tree-based model of natural forest gap dynamics (FORMIX) to simulate forest recovery following logging. Input variables included stand structure, volume extracted, stand damage (% stems), and soil disturbance (% area compacted). Output variables included total biomass, tree density, and total carbon storage over time. Assumptions of the model included the following: (1) areas with soil disturbances have elevated probabilities of vine colonization and reduced rates of tree establishment, (2) areas with broken canopy but no soil disturbance are colonized initially by pioneer tree species and 20 yr later by persistent forest species, (3) damaged trees have reduced growth and increased mortality rates. Simulation results for two logging techniques, conventional and reduced-impact logging, are compared with data from field studies conducted within a pilot carbon offset project in Sabah, Malaysia.

Pinard, M.A. [Univ. of Florida, Gainesville, FL (United States)

1995-09-01T23:59:59.000Z

183

Scalar products in models with GL(3) trigonometric R-matrix. Determinant representation  

E-Print Network [OSTI]

We study quantum integrable models with the GL(3) trigonometric R-matrix solvable by the nested algebraic Bethe ansatz. We derive a determinant representation for a special case of scalar products of Bethe vectors. This representation allows one to find a determinant formula for form factor of one of the monodromy matrix entries. We also point out essential difference between form factors in the models with the Gl(3) trigonometric R-matrix and their analogs in GL(3)-invariant models.

N. A. Slavnov

2015-01-26T23:59:59.000Z

184

Modeling high-pressure adsorption of gas mixtures on activated carbon and coal using a simplified local-density model  

SciTech Connect (OSTI)

The simplified local-density (SLD) theory was investigated regarding its ability to provide accurate representations and predictions of high-pressure supercritical adsorption isotherms encountered in coalbed methane (CBM) recovery and CO{sub 2} sequestration. Attention was focused on the ability of the SLD theory to predict mixed-gas adsorption solely on the basis of information from pure gas isotherms using a modified Peng-Robinson (PR) equation of state (EOS). An extensive set of high-pressure adsorption measurements was used in this evaluation. These measurements included pure and binary mixture adsorption measurements for several gas compositions up to 14 MPa for Calgon F-400 activated carbon and three water-moistened coals. Also included were ternary measurements for the activated carbon and one coal. For the adsorption of methane, nitrogen, and CO{sub 2} on dry activated carbon, the SLD-PR can predict the component mixture adsorption within about 2.2 times the experimental uncertainty on average solely on the basis of pure-component adsorption isotherms. For the adsorption of methane, nitrogen, and CO{sub 2} on two of the three wet coals, the SLD-PR model can predict the component adsorption within the experimental uncertainties on average for all feed fractions (nominally molar compositions of 20/80, 40/60, 60/40, and 80/20) of the three binary gas mixture combinations, although predictions for some specific feed fractions are outside of their experimental uncertainties.

Fitzgerald, J.E.; Robinson, R.L.; Gasem, K.A.M. [Oklahoma State University, Stillwater, OK (United States). School of Chemical Engineering

2006-11-07T23:59:59.000Z

185

A Finite-Element Model for Simulation of Carbon Dioxide Sequestration  

SciTech Connect (OSTI)

Herein, we present a coupled thermal-hydro-mechanical model for geological sequestration of carbon dioxide followed by the stress, deformation, and shear-slip failure analysis. This fully coupled model considers the geomechanical response, fluid flow, and thermal transport relevant to geological sequestration. Both analytical solutions and numerical approach via finite element model are introduced for solving the thermal-hydro-mechanical model. Analytical solutions for pressure, temperature, deformation, and stress field were obtained for a simplified typical geological sequestration scenario. The finite element model is more general and can be used for arbitrary geometry. It was built on an open-source finite element code, Elmer, and was designed to simulate the entire period of CO2 injection (up to decades) both stably and accuratelyeven for large time steps. The shear-slip failure analysis was implemented based on the numerical results from the finite element model. The analysis reveals the potential failure zone caused by the fluid injection and thermal effect. From the simulation results, the thermal effect is shown to enhance well injectivity, especially at the early time of the injection. However, it also causes some side effects, such as the appearance of a small failure zone in the caprock. The coupled thermal-hydro-mechanical model improves prediction of displacement, stress distribution, and potential failure zone compared to the model that neglects non-isothermal effects, especially in an area with high geothermal gradient.

Bao, Jie; Xu, Zhijie; Fang, Yilin

2014-09-01T23:59:59.000Z

186

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.

Jakubsky, Vit; Negro, Javier

2013-01-01T23:59:59.000Z

187

A model to determine financial indicators for organic solar cells  

SciTech Connect (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

188

Modeling Electrochemical Decomposition of Fluoroethylene Carbonate on Silicon Anode Surfaces in Lithium Ion Batteries  

E-Print Network [OSTI]

Fluoroethylene carbonate (FEC) shows promise as an electrolyte additive for improving passivating solid-electrolyte interphase (SEI) films on silicon anodes used in lithium ion batteries (LIB). We apply density functional theory (DFT), ab initio molecular dynamics (AIMD), and quantum chemistry techniques to examine excess-electron-induced FEC molecular decomposition mechanisms that lead to FEC-modified SEI. We consider one- and two-electron reactions using cluster models and explicit interfaces between liquid electrolyte and model Li(x)Si(y) surfaces, respectively. FEC is found to exhibit more varied reaction pathways than unsubstituted ethylene carbonate. The initial bond-breaking events and products of one- and two-electron reactions are qualitatively similar, with a fluoride ion detached in both cases. However, most one-electron products are charge-neutral, not anionic, and may not coalesce to form effective Li+-conducting SEI unless they are further reduced or take part in other reactions. The implications of these reactions to silicon-anode based LIB are discussed.

Kevin Leung; Susan B. Rempe; Michael E. Foster; Yuguang Ma; Julibeth M. Martinez del la Hoz; Na Sai; Perla B. Balbuena

2014-01-17T23:59:59.000Z

189

Summary Gross canopy photosynthesis (Pg) can be simu-lated with canopy models or retrieved from turbulent carbon  

E-Print Network [OSTI]

turbulent carbon dioxide (CO2) flux measurements above the forest canopy. We compare the two estimates Pg of two spruce forests differing in age and structure. Model parameter acquisition and model sen flux estimates. Despite higher photon fluxes at the site, an older German Norway spruce (Picea abies L

190

An analytical model to predict curvature effects of the carbon nanotube on the overall behavior of nanocomposites  

SciTech Connect (OSTI)

In this study, analytical expressions are introduced to provide a better understanding of carbon nanotubes (CNTs) curvature on the overall behavior of nanocomposites. The curviness of CNT is modeled as the wave geometries, and the transformed physical characteristics are applied to micromechanical framework. Since five independent elastic constants of CNTs are essential to derive the waviness effect, atomistic molecular statics simulations with varying nanotube radii are conducted. Influences of CNT curviness on the effective stiffness of the nanocomposites are analyzed, noting that the curvature effect is significantly influential on the effective stiffness of the nanocomposites, and it may improve or reduce the reinforcing effect depending on the orientation of CNTs. In addition, the predictions are compared with experimental data of the CNT-reinforced nanocomposites to assess the reliability of the proposed method. The developed constitutive model is expected to be used to determine the volume concentration of the reinforcing CNTs and mechanical responses of CNT-reinforced composites under various CNT curvature, radius, and orientation conditions.

Yang, B. J.; Souri, H.; Lee, H. K., E-mail: leeh@kaist.ac.kr [Department of Civil and Environmental Engineering, Korea Advanced Institute of Science and Technology (KAIST), 291 Daehak-ro, Yuseong-gu, Daejeon 305-701 (Korea, Republic of); Kim, Sunghwan; Ryu, Seunghwa [Department of Mechanical Engineering, Korea Advanced Institute of Science and Technology (KAIST), 291 Daehak-ro, Yuseong-gu, Daejeon 305-701 (Korea, Republic of)

2014-07-21T23:59:59.000Z

191

Universal field-emission model for carbon nanotubes on a metal tip D. Y. Zhong, G. Y. Zhang, and S. Liu  

E-Print Network [OSTI]

Universal field-emission model for carbon nanotubes on a metal tip D. Y. Zhong, G. Y. Zhang, and S Electron-field-emission properties have been investigated systematically for carbon nanotubes CNTs.1063/1.1430507 Carbon nanotubes CNTs have excellent electron-field- emission properties because of their electronic

Zhang, Guangyu

192

A conceptual model for determining yield loss due to drought stress in sorghum  

E-Print Network [OSTI]

A CONCEPTUAL MODEL FOR DETERMINING YIELD LOSS DUE TO DROUGHT STRESS IN SORGHUM A Thesis by PAUL ROBERT KOCH Submitted to the Graduate College of Texas AkM University in partial fulfillment of the requirements for the degree of MASTER... OF SCIENCE May 1987 Major Subject: Agricultural Engineering A CONCEPTUAL MODEL FOR DETERMINING YIELD LOSS DUE TO DROUGHT STRESS IN SORGHUM A thesis by PAUL ROBERT KOCH Approved as to style and content by: Marshall J. McFarland (Chair of Committee...

Koch, Paul Robert

1987-01-01T23:59:59.000Z

193

Radiometric Modeling of Cavernous Targets to Assist in the Determination of Absolute Temperature  

E-Print Network [OSTI]

Radiometric Modeling of Cavernous Targets to Assist in the Determination of Absolute Temperature108, Aiken, SC, USA ABSTRACT Determining the temperature of an internal surface within cavernous of these internal surfaces. The cavernous target has often been assumed to be a blackbody, but in field experiments

Salvaggio, Carl

194

Model-data Fusion Approaches for Retrospective and Predictive Assessment of the Pan-Arctic Scale Permafrost Carbon Feedback to Global Climate  

E-Print Network [OSTI]

representation of the Arctic system carbon cycle in Earth System Modeling frameworks. This proposed study of permafrost carbon processes in terrestrial biogeochemistry models, to operate within coupled Earth system modeling frameworks. PROJECT SIGNIFICANCE This work will provide a critical bridge between the abundant

195

A Micromechanical Constitutive Model of Progressive Crushing in Random Carbon Fiber Polymer Matrix Composites  

SciTech Connect (OSTI)

A micromechanical damage constitutive model is presented to predict the overall elastoplastic behavior and damage evolution in random carbon fiber polymer matrix composites (RFPCs).To estimate the overall elastoplastic damage responses,an effective yield criterion is derived based on the ensemble-volume averaging process and first-order effects of eigenstrains due to the existence of spheroidal (prolate) fibers.The proposed effective yield criterion,to ether with the assumed overall associative plastic flow rule and hardening law, constitutes the analytical foundation for the estimation of effective elastoplastic behavior of ductile matrix composites.First,an effective elastoplastic constitutive dama e model for aligned fiber-reinforced composites is proposed.A micromechanical damage constitutive model for RFPCs is then developed.The average process over all orientations upon overning constitutive field equations and overall yield function for aligned fiber-reinforced composites i s performed to obtain the constitutive relations and effective yield function of RFPCs.The discrete numerical integration algorithms and the continuum tan ent operator are also presented to implement the proposed dama e constitutive model.The dama e constitutive model forms the basis for the pro ressive crushing in composite structures under impact loading.

Lee, H.K.; Simunovic, S.

1999-09-01T23:59:59.000Z

196

EDGE2D-EIRENE Modelling of Divertor Detachment in JET High Triangularity L-mode Plasmas in Carbon and Be/W Environment  

E-Print Network [OSTI]

EDGE2D-EIRENE Modelling of Divertor Detachment in JET High Triangularity L-mode Plasmas in Carbon and Be/W Environment

197

Recovery Boiler Modeling: An Improved Char Burning Model Including Sulfate Reduction and Carbon Removal  

E-Print Network [OSTI]

gasification, reactions between oxygen and combustibles in the boundary layer, and integration of sulfate reduction and sulfide reoxidation into the char burning process. Simulations using the model show that for typical recovery boiler conditions, char burning...

Grace, T. M.; Wag, K. J.; Horton, R. R.; Frederick, W. J.

198

Determinant representations for form factors in quantum integrable models with GL(3)-invariant R-matrix  

E-Print Network [OSTI]

We obtain determinant representations for the form factors of the monodromy matrix entries in quantum integrable models solvable by the nested algebraic Bethe ansatz and possessing $GL(3)$-invariant $R$-matrix. These representations can be used for the calculation of correlation functions in the models of physical interest.

S. Pakuliak; E. Ragoucy; N. A. Slavnov

2014-06-19T23:59:59.000Z

199

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

SciTech Connect (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

200

Exploration applications of a transgressive tidal flats model to Mississippian Midale carbonates, eastern Williston Basin  

SciTech Connect (OSTI)

Midale (Mississippian) production was first established in 1953 in Saskatchewan, Canada. The unit was initially defined in the subsurface as the carbonate interval between the top of the Frobisher Anhydrite and the base of the Midale Anhydrite. That nomenclature is used in this report. During 1953, Midale production was found in the United States portion of the Williston basin in Bottineau County, North Dakota. Later exploration extended Midale production westward into Burke County, North Dakota. Cumulative production from the Midale is approximately 660 million bbl, of which 640 million bbl are from Canadian fields. Initially, hydrocarbon entrapment in the Midale was believed to be controlled by the Mississippian subcrop, with the Burke County production controlled by low-relief structural closure. Petrographic examination of cores and cuttings from the Midale in both Saskatchewan, Canada, and Burke and Bottineau Counties, North Dakota, indicates that production is controlled by facies changes within the unit. Stratigraphic traps are formed by the lateral and vertical changes from grain-supported facies deposited in tidal channel, subtidal bar, or beach settings; seals are formed by mud-rich sediments. Use of a transgressive carbonate tidal flats model best explains current production patterns and indicates substantial potential for additional production in eastern North Dakota and South Dakota.

Porter, L.A.; Reid, R.S.R.

1985-05-01T23:59:59.000Z

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201

Exploration applications of a transgressive tidal-flats model to Mississippian Midale carbonates, eastern Williston Basin  

SciTech Connect (OSTI)

Midale (Mississippian) production was first indicated in 1953 in Saskatchewan, Canada. The unit was initially defined in the subsurface as the carbonate interval between the top of the Frobisher Anhydrite and the base of the Midale Anhydrite. This same nomenclature is used in this paper. In 1953, Midale production was found on the US side of the Williston basin in Bottineau County, North Dakota. Later exploration extended Midale production westward into Burke County, North Dakota, in 1955. Cumulative production from the Midale is approximately 660 million bbl with 640 million from the Canadian side of the Williston basin. Initially, hydrocarbon entrapment in the Midale was believed to be controlled by the Mississippian subcrop, with the Burke County production controlled by low-relief structural closure. Petrographic examination of cores and cuttings from the Midale in both Saskatchewan, Canada, and Burke and Bottineau Counties, North Dakota, indicates that production is controlled by facies changes within the unit. Stratigraphic traps are formed by the lateral and vertical changes from grain-supported facies deposited in tidal-channel, subtidal-bar, or beach settings; seals are formed by mud-rich sediments. Use of a transgressive carbonate tidal-flats model best explains current production patterns and indicates substantial potential for additional production in eastern North Dakota and South Dakota.

Porter, L.A.; Reid, F.S.

1985-02-01T23:59:59.000Z

202

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...

Truong, Hieu 1990-

2012-12-04T23:59:59.000Z

203

Carbon nanotube mats and fibers with irradiationimproved mechanical characteristics: a theoretical model  

E-Print Network [OSTI]

1 Carbon nanotube mats and fibers with irradiation­improved mechanical characteristics characteristics of macroscopic mats and fibers of single­walled carbon nanotubes. We further investigate, which in contrast to most ordinary carbon fibers could be strongly bent without breaking, had much

Nordlund, Kai

204

Carbon nanotube mats and fibers with irradiation-improved mechanical characteristics: a theoretical model  

E-Print Network [OSTI]

1 Carbon nanotube mats and fibers with irradiation-improved mechanical characteristics characteristics of macroscopic mats and fibers of single-walled carbon nanotubes. We further investigate]. The SWNT fibers, which in contrast to most ordinary carbon fibers could be strongly bent without breaking

Nordlund, Kai

205

Distant origins of Arctic black carbon: A Goddard Institute for Space Studies ModelE experiment  

E-Print Network [OSTI]

[Wallace and Thompson, 2002]. The Arctic climate is especially sensitive to changes in the hydrological005296. 1. Introduction [2] The Arctic is a particularly sensitive region to global climate change. Observations and models indicate that as the climate warms, the Arctic warms most and fastest [e.g., Manabe et

206

Modifying the Soil and Water Assessment Tool to Simulate Cropland Carbon Flux: Model Development and Initial Evaluation  

SciTech Connect (OSTI)

Climate change is one of the most compelling modern issues and has important implications for almost every aspect of natural and human systems. The Soil and Water Assessment Tool (SWAT) model has been applied worldwide to support sustainable land and water management in a changing climate. However, the inadequacies of the existing carbon algorithm in SWAT limit its application in assessing impacts of human activities on CO2 emission, one important source of greenhouse gases (GHGs) that traps heat in the earth system and results in global warming. In this research, we incorporate a revised version of the CENTURY carbon model into SWAT to describe dynamics of soil organic matter (SOM)- residue and simulate land-atmosphere carbon exchange.

Zhang, Xuesong; Izaurralde, Roberto C.; Arnold, Jeffrey; Williams, Jimmy R.; Srinivasan, Raghavan

2013-10-01T23:59:59.000Z

207

1994 conceptual model of the carbon tetrachloride contamination in the 200 West Area at the Hanford Site  

SciTech Connect (OSTI)

Between 1955 and 1973, a total of 363,000 to 580,000 L (577,000 to kg) of liquid carbon tetrachloride, in mixtures with other organic and aqueous, actinide-bearing fluids, were discharged to the soil column at three disposal facilities -- the 216-Z-9 Trench, the 216-Z-lA TiTe Field, and the 216-Z-18 Crib -- in the 200 West Area at the Hanford Site. In the mid-1980`s, dissolved carbon tetrachloride was found in the uppermost aquifer beneath the disposal facilities, and in late 1990, the US Environmental Protection Agency and the Washington State Department of Ecology requested that the US Department of Energy proceed with planning and implementation of an expedited response action (ERA) to minimize additional carbon tetrachloride contamination of the groundwater. In February 1992, soil vapor extraction was initiated to remove carbon tetrachloride from the unsaturated zone beneath these disposal facilities. By May 1994, a total of 10,560 L (16,790 kg) of carbon tetrachloride had been removed, amounting to an estimated 2% of the discharged inventory. In the spring of 1991, the Volatile Organic Compounds -- Arid Integrated Demonstration (VOC-Arid ID) program selected the carbon tetrachloride-contaminated site for demonstration and deployment of new technologies for evaluation and cleanup of volatile organic compounds and associated contaminants in soils and groundwater at arid sites. Site investigations conducted in support of both the ERA and the VOC-Arid ID have been integrated because of their shared objective to refine the conceptual model of the site and to promote efficiency. Site characterization data collected in fiscal year 1993 have supported and led to refinement of the conceptual model of the carbon tetrachloride site.

Rohay, V.J.

1994-08-01T23:59:59.000Z

208

Modeling Mud-Filtrate Invasion Effects on Resistivity Logs to Estimate Permeability of Vuggy and Fractured Carbonate Formations  

E-Print Network [OSTI]

SPE 121136 Modeling Mud-Filtrate Invasion Effects on Resistivity Logs to Estimate Permeability to diagnose and estimate secondary porosity and absolute permeability of fractured and vuggy carbonate-connected) and fractured porosity, all embedded in a tight matrix. Rock-core data and wellbore resistivity images indicate

Torres-Verdín, Carlos

209

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

E-Print Network [OSTI]

High-resolution modeling of the western North American power system demonstrates low-cost and low energy Carbon emissions a b s t r a c t Decarbonizing electricity production is central to reducing of resource cost scenarios, most coal power plants would be replaced by solar, wind, gas, and/or nuclear

Kammen, Daniel M.

210

A Model of Transient Thermal Transport Phenomena Applied to the Carbonation and Calcination of a Sorbent Particle for Calcium Oxide Looping CO2 Capture  

E-Print Network [OSTI]

looping is selected as the model cycle because of its suitability for solar-driven carbon dioxide captureA Model of Transient Thermal Transport Phenomena Applied to the Carbonation and Calcination of a Sorbent Particle for Calcium Oxide Looping CO2 Capture Lindsey Yue and Wojciech Lipi´nski, The Australian

211

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

E-Print Network [OSTI]

Ogden models use capital cost estimates from Skovholts 1993are below average but estimate capital costs that are abovediameter, it estimates capital cost below the average.

McCollum, David L; Ogden, Joan M

2006-01-01T23:59:59.000Z

212

ISSUES IN EVALUATING CARBON SEQUESTRATION AND ATTRIBUTING CARBON CREDITS TO GRASSLAND RESTORATION EFFORTS  

E-Print Network [OSTI]

ISSUES IN EVALUATING CARBON SEQUESTRATION AND ATTRIBUTING CARBON CREDITS TO GRASSLAND RESTORATION examines biological carbon sequestration using a grassland restoration as a model system. Chapter 1 for biological carbon sequestration. In this analysis, we found that significantly greater soil carbon

Wisconsin at Madison, University of

213

Regional scale cropland carbon budgets: evaluating a geospatial agricultural modeling system using inventory data  

SciTech Connect (OSTI)

Accurate quantification and clear understanding of regional scale cropland carbon (C) cycling is critical for designing effective policies and management practices that can contribute toward stabilizing atmospheric CO2 concentrations. However, extrapolating site-scale observations to regional scales represents a major challenge confronting the agricultural modeling community. This study introduces a novel geospatial agricultural modeling system (GAMS) exploring the integration of the mechanistic Environmental Policy Integrated Climate model, spatially-resolved data, surveyed management data, and supercomputing functions for cropland C budgets estimates. This modeling system creates spatially-explicit modeling units at a spatial resolution consistent with remotely-sensed crop identification and assigns cropping systems to each of them by geo-referencing surveyed crop management information at the county or state level. A parallel computing algorithm was also developed to facilitate the computationally intensive model runs and output post-processing and visualization. We evaluated GAMS against National Agricultural Statistics Service (NASS) reported crop yields and inventory estimated county-scale cropland C budgets averaged over 20002008. We observed good overall agreement, with spatial correlation of 0.89, 0.90, 0.41, and 0.87, for crop yields, Net Primary Production (NPP), Soil Organic C (SOC) change, and Net Ecosystem Exchange (NEE), respectively. However, we also detected notable differences in the magnitude of NPP and NEE, as well as in the spatial pattern of SOC change. By performing crop-specific annual comparisons, we discuss possible explanations for the discrepancies between GAMS and the inventory method, such as data requirements, representation of agroecosystem processes, completeness and accuracy of crop management data, and accuracy of crop area representation. Based on these analyses, we further discuss strategies to improve GAMS by updating input data and by designing more efficient parallel computing capability to quantitatively assess errors associated with the simulation of C budget components. The modularized design of the GAMS makes it flexible to be updated and adapted for different agricultural models so long as they require similar input data, and to be linked with socio-economic models to understand the effectiveness and implications of diverse C management practices and policies.

Zhang, Xuesong; Izaurralde, Roberto C.; Manowitz, David H.; Sahajpal, Ritvik; West, Tristram O.; Thomson, Allison M.; Xu, Min; Zhao, Kaiguang; LeDuc, Stephen D.; Williams, Jimmy R.

2015-01-01T23:59:59.000Z

214

Atmospheric Carbon Dioxide Variability in the Community Earth System Model: Evaluation and Transient Dynamics during the Twentieth and Twenty-First Centuries  

E-Print Network [OSTI]

Atmospheric Carbon Dioxide Variability in the Community Earth System Model: Evaluation pathways (RCPs 4.5 and 8.5) using the Community Earth System Model­Biogeochemistry (CESM1- BGC). CO2

Hoffman, Forrest M.

215

Modeling geologic storage of carbon dioxide: Comparison ofnon-hysteretic chracteristic curves  

SciTech Connect (OSTI)

TOUGH2 models of geologic storage of carbon dioxide (CO2) in brine-bearing formations use characteristic curves to represent the interactions of non-wetting-phase CO2 and wetting-phase brine. When a problem includes both injection of CO2 (a drainage process) and its subsequent post-injection evolution (a combination of drainage and wetting), hysteretic characteristic curves are required to correctly capture the behavior of the CO2 plume. In the hysteretic formulation, capillary pressure and relative permeability depend not only on the current grid-block saturation, but also on the history of the saturation in the grid block. For a problem that involves only drainage or only wetting, a nonhysteretic formulation, in which capillary pressure and relative permeability depend only on the current value of the grid-block saturation, is adequate. For the hysteretic formulation to be robust computationally, care must be taken to ensure the differentiability of the characteristic curves both within and beyond the turning-point saturations where transitions between branches of the curves occur. Two example problems involving geologic CO2 storage are simulated using non-hysteretic and hysteretic models, to illustrate the applicability and limitations of non-hysteretic methods: the first considers leakage of CO2 from the storage formation to the ground surface, while the second examines the role of heterogeneity within the storage formation.

Doughty, Christine

2006-04-28T23:59:59.000Z

216

Model Independent Determination of the Solar Neutrino Spectrum with and without MSW  

E-Print Network [OSTI]

Besides the opportunity for discovering new neutrino physics, solar neutrino measurements provide a sensitive probe of the solar interior, and thus a rigorous test of solar model predictions. We present model independent determinations of the neutrino spectrum by using relevant flux components as free parameters subject only to the luminosity constraint. (1) Without the Mikheyev-Smirnov-Wolfenstein (MSW) effect, the best fit for the combined data is poor. Furthermore, the data indicate a severe suppression of the $^7$Be flux relative to the $^8$B, contradicting both standard and nonstandard solar models in general; the $pp$ flux takes its maximum value allowed by the luminosity constraint. This pathology consistently appears even if we ignore any one of the three data. (2) In the presence of the two-flavor MSW effect, the current constraint on the initial $^8$B flux is weak, but consistent with the SSM and sufficient to exclude nonstandard models with small $^8$B fluxes. No meaningful constraint is obtained for the other fluxes. In the future, even allowing MSW, the $^8$B and $^7$Be fluxes can be determined at the $\\pm$(15 -- 20)\\% level, making competing solar models distinguishable. We emphasize that the neutral current sensitivity for $^7$Be neutrinos in BOREXINO, HELLAZ, and HERON is essential for determining the initial fluxes. The constraints on the MSW parameters in the model independent analysis are also discussed.

Naoya Hata; Paul Langacker

1994-09-21T23:59:59.000Z

217

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

E-Print Network [OSTI]

Costs to Estimate Hydrogen Pipeline Costs, UCD-ITS-RR-04-predict the costs of hydrogen pipelines, all of the modelspredict the costs of hydrogen pipelines, all of the models

McCollum, David L; Ogden, Joan M

2006-01-01T23:59:59.000Z

218

TEXIN2: a model for predicting carbon monoxide concentrations near intersections  

E-Print Network [OSTI]

reduction caused by congestion 49 10 Application of impedance factors Carbon monoxide emissions for vehicular speed changes 59 12 Pasquill stability classes, A-G, as related to wind speed and incoming solar radiation 77 13 Regression lines... The prediction of carbon monoxide concentrations near roadway intersections represents a serious and challenging problem in air pollution research. In many geographical regions, the major portion of carbon monoxide in the environment is attributable...

Korpics, J. J

1985-01-01T23:59:59.000Z

219

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

E-Print Network [OSTI]

marine carbon uptake, Biogeosciences, 6, 16031613, doi:10.5194/bg- 6-1603-2009, 2009. www.biogeosciences.net/

2011-01-01T23:59:59.000Z

220

Carbonation Mechanism of Reservoir Rock by Supercritical Carbon...  

Open Energy Info (EERE)

from reservoir rock formation. - Task 2: Carbonation study of minerals. - Task 3: Mechanical behaviors of carbonated minerals. - Task 4: Modeling of CO2- reservoir rock...

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

Determination of structural characteristics of saturates from diesel and kerosene fuels by carbon-13 nuclear magnetic resonance spectrometry  

SciTech Connect (OSTI)

Two saturated hydrocarbon fractions, one mainly consisting of n-alkanes and the other containing only branched plus cyclic saturates, have been separated from each of a variety of diesel fuels (approximate boiling range 230-320/sup 0/C) and kerosene fuels (approximately 190-230/sup 0/C) using silica chromatography and urea clathration. The n-alkane fractions have been simply characterized by using conventional /sup 13/C NMR spectrometry, yielding average carbon chain lengths. The branched plus cyclic saturates fractions have been characterized by using the gated spin echo (GASPE) /sup 13/C NMR subspectra for each CH/sub n/ group type (n = 0 to 3) and allows the fractional abundances of CH/sub n/ groups to be measured. These data have been employed in devising and calculating a number of novel average structure parameters which report on the extent of branching and occurrence of ring structures in the fractions investigated. Spectral data are also used to identify some specific submolecular structures. 29 references, 7 figures, 4 tables.

Cookson, D.J.; Smith, B.E.

1985-04-01T23:59:59.000Z

222

Modelling and development of carbon molecular sieve membrane for gas separation.  

E-Print Network [OSTI]

??The objective of the research project was to investigate the feasibility of preparing carbon molecular sieve membranes from Kapton polyimide film. The effects of carbonisation (more)

Su, Jincai.

2008-01-01T23:59:59.000Z

223

Determination of Non{Adiabatic Scattering Wave Functions in a Born{Oppenheimer Model  

E-Print Network [OSTI]

Determination of Non{Adiabatic Scattering Wave Functions in a Born{Oppenheimer Model George A for the time dependent molecular Schrodinger equation in the Born{Oppenheimer limit. We assume the elec- tron. This component is shown to be exponentially small in the square of the Born{Oppenheimer parameter, due

Hagedorn, George A.

224

Determination of Non--Adiabatic Scattering Wave Functions in a Born--Oppenheimer Model  

E-Print Network [OSTI]

Determination of Non--Adiabatic Scattering Wave Functions in a Born--Oppenheimer Model George A molecular Schr?odinger equation in the Born--Oppenheimer limit. We assume the elec­ tron Hamiltonian has to be exponentially small in the square of the Born--Oppenheimer parameter, due to the Landau­Zener mechanism

225

Determination of Peptide Amide Configuration in a Model Amyloid Fibril by Solid-State NMR  

E-Print Network [OSTI]

-42, with sequence LMVGGVVIA) forms a structured aggregate which is classified as an amyloid fibril based primarilyDetermination of Peptide Amide Configuration in a Model Amyloid Fibril by Solid-State NMR P. R these aggregates form. The primary constituent of the amyloid plaques characteristic of AD are a family of 39

Griffin, Robert G.

226

An Ontology-based Model to Determine the Automation Level of an Automated Vehicle for  

E-Print Network [OSTI]

An Ontology-based Model to Determine the Automation Level of an Automated Vehicle for Co). In addition, an automated vehicle should also self-assess its own perception abilities, and not only perceive this idea, cybercars were designed as fully automated vehicles [3], thought since its inception as a new

Paris-Sud XI, Université de

227

Pacific Northwest rangeland carbon sequestration.  

E-Print Network [OSTI]

??This paper models the supply curve of carbon sequestration on Pacific Northwest rangelands. Rangeland managers have the ability to sequester carbon in agricultural soils by (more)

Wiggins, Seth T.

2012-01-01T23:59:59.000Z

228

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

229

Modeling of Water-rock interaction in the Mackenzie Basin: competition between sulfuric and carbonic acids  

E-Print Network [OSTI]

sulfuric and carbonic acids E. Beaulieu, Y. Godd´eris, D. Labat, C. Roelandt, D. Calmels, J. Gail- lardet of the resulting proof before it is published in its final form. Please note that during the production process in the Mackenzie Basin: competition between sulfuric and carbonic acids. E. Beaulieu1 , Y. Goddéris1 , D. Labat1

230

Reduced-Order Model for the Geochemical Impacts of Carbon Dioxide, Brine and Trace Metal Leakage into an Unconfined, Oxidizing Carbonate Aquifer, Version 2.1  

SciTech Connect (OSTI)

The National Risk Assessment Partnership (NRAP) consists of 5 U.S DOE national laboratories collaborating to develop a framework for predicting the risks associated with carbon sequestration. The approach taken by NRAP is to divide the system into components, including injection target reservoirs, wellbores, natural pathways including faults and fractures, groundwater and the atmosphere. Next, develop a detailed, physics and chemistry-based model of each component. Using the results of the detailed models, develop efficient, simplified models, termed reduced order models (ROM) for each component. Finally, integrate the component ROMs into a system model that calculates risk profiles for the site. This report details the development of the Groundwater Geochemistry ROM for the Edwards Aquifer at PNNL. The Groundwater Geochemistry ROM for the Edwards Aquifer uses a Wellbore Leakage ROM developed at LANL as input. The detailed model, using the STOMP simulator, covers a 5x8 km area of the Edwards Aquifer near San Antonio, Texas. The model includes heterogeneous hydraulic properties, and equilibrium, kinetic and sorption reactions between groundwater, leaked CO2 gas, brine, and the aquifer carbonate and clay minerals. Latin Hypercube sampling was used to generate 1024 samples of input parameters. For each of these input samples, the STOMP simulator was used to predict the flux of CO2 to the atmosphere, and the volume, length and width of the aquifer where pH was less than the MCL standard, and TDS, arsenic, cadmium and lead exceeded MCL standards. In order to decouple the Wellbore Leakage ROM from the Groundwater Geochemistry ROM, the response surface was transformed to replace Wellbore Leakage ROM input parameters with instantaneous and cumulative CO2 and brine leakage rates. The most sensitive parameters proved to be the CO2 and brine leakage rates from the well, with equilibrium coefficients for calcite and dolomite, as well as the number of illite and kaolinite sorption sites proving to be of secondary importance. The Groundwater Geochemistry ROM was developed using nonlinear regression to fit the response surface with a quadratic polynomial. The goodness of fit was excellent for the CO2 flux to the atmosphere, and very good for predicting the volumes of groundwater exceeding the pH, TDS, As, Cd and Pb threshold values.

Bacon, Diana H.

2013-03-31T23:59:59.000Z

231

ATOMIC-LEVEL MODELING OF CO2 DISPOSAL AS A CARBONATE MINERAL: A SYNERGETIC APPROACH TO OPTIMIZING REACTION PROCESS DESIGN  

SciTech Connect (OSTI)

Fossil fuels, especially coal, can support the energy demands of the world for centuries to come, if the environmental problems associated with CO{sub 2} emissions can be overcome. Permanent and safe methods for CO{sub 2} capture and disposal/storage need to be developed. Mineralization of stationary-source CO{sub 2} emissions as carbonates can provide such safe capture and long-term sequestration. Mg-rich lamellar hydroxide mineral carbonation is a leading process candidate, which generates the stable naturally occurring mineral magnesite (MgCO{sub 3}) and water. Key to process cost and viability are the carbonation reaction rate and its degree of completion. This process, which involves simultaneous dehydroxylation and carbonation is very promising, but far from optimized. In order to optimize the dehydroxylation/carbonation process, an atomic-level understanding of the mechanisms involved is needed. In this investigation Mg(OH){sub 2} was selected as a model Mg-rich lamellar hydrocide carbonation feedstock material due to its chemical and structural simplicity. Since Mg(OH){sub 2} dehydroxylation is intimately associated with the carbonation process, its mechanisms are also of direct interest in understanding and optimizing the process. The aim of the current innovative concepts project is to develop a specialized advanced computational methodology to complement the ongoing experimental inquiry of the atomic level processes involved in CO{sub 2} mineral sequestration. The ultimate goal is to integrate the insights provided by detailed predictive simulations with the data obtained from optical microscopy, FESEM, ion beam analysis, SIMS, TGA, Raman, XRD, and C and H elemental analysis. The modeling studies are specifically designed to enhance the synergism with, and complement the analysis of, existing mineral-CO{sub 2} reaction process studies being carried out under DOE UCR Grant DE-FG2698-FT40112. Direct contact between the simulations and the experimental measurements is provided by computing, from first principles, the equilibrium structures, elastic, optical, and vibrational properties of Mg(OH){sub 2} (brucite), MgO (periclase), MgCO{sub 3} (magnesite), as well as the energetics of the dehydroxylation reaction (Mg(OH){sub 2} {yields} MgO + H{sub 2}O), and the reactivity of CO{sub 2} with MgO and Mg(OH){sub 2}. From these calculations, thermodynamic characteristics of the reaction conditions can be inferred. This kind of information, when integrated with the atomic level data obtained from experimental gas-solid dehydroxylation/carbonation studies, will be used to design optimized reaction processes leading to the practical and cost-effective sequestration of CO{sub 2} in mineral form.

A.V.G. Chizmeshya; M.J. McKelvy; J.B. Adams

2001-11-01T23:59:59.000Z

232

Predicting the oceanic input of organic carbon by continental erosion  

SciTech Connect (OSTI)

Empirical models were developed to describe relationships between the climatic, biologic, and geomorphologic characteristics of major world rivers and the observed dissolved and particulate carbon fluxes. The main purpose of the study was to determine the best regression models to describe river carbon flux at a global scale. Model parameters were grouped in all possible combinations and in a way to minimize the effects of multicollinearity. All parameter combinations were then tested individually. A model was developed with parameters which corresponded well to field results and global carbon fluxes which were close to previous estimates. The model was also used to relate the variability of annual carbon fluxes to the environmental variability of river basins. The statistical approach allows only a general view, but is capable of identifying the principal factors controlling global organic carbon flux. 111 refs., 5 figs., 4 tabs.

Ludwig, W.; Probst, J.C. [Centre National de la Recherche Scientifique, Strasbourg (France)] [Centre National de la Recherche Scientifique, Strasbourg (France); Kempe, S. [Technische Hochschule Darmstadt (Germany)] [Technische Hochschule Darmstadt (Germany)

1996-03-01T23:59:59.000Z

233

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

234

Historical and future black carbon deposition on the three ice caps: Ice core measurements and model simulations from 1850 to 2100  

E-Print Network [OSTI]

Historical and future black carbon deposition on the three ice caps: Ice core measurements black carbon deposition on the three ice caps: Ice core measurements and model simulations from 1850 tends to enhance snow and ice melting due to the absorption caused by the increased BC deposition

235

CARBON-CARBON COMPOSITE ALLCOMP Carbon-Carbon Composite  

E-Print Network [OSTI]

materials. MATERIALS AND DESIRED DATA Carbon-Carbon Composites(T300 & SWB): Crush Resistance, Bend StrengthCARBON-CARBON COMPOSITE ALLCOMP Carbon-Carbon Composite · C-C supplied in two forms · T300: C strength 4340 steel, carbon-carbon composite, and Carbon-Silicon Carbide composite were tested to examine

Rollins, Andrew M.

236

Model independent determination of the spin of the {sup 180}Ta naturally occurring isomer  

SciTech Connect (OSTI)

The hyperfine structures of the 33715.27 cm{sup -1} and 33706.47 cm{sup -1} transitions from the ground state of singly ionized Ta have been measured by collinear laser spectroscopy. The structures were found to contain a large second order contribution. From fitting the observed hyperfine components for both {sup 181}Ta and the {sup 180}Ta naturally occurring isomer it was possible to determine the first and second order hyperfine structure coefficients. As no model independent determination of the nuclear spin of the {sup 180}Ta isomer has been performed, fitting was attempted for a range of spins. A clear chi-squared minimum is obtained for a nuclear spin of 9, in agreement with model dependent measurements.

Bissell, M. L.; Baczynska, K.; Forest, D. H.; Gardner, M. D.; Tungate, G. [School of Physics and Astronomy, The University of Birmingham, Edgbaston, Birmingham B15 2TT (United Kingdom); Billowes, J.; Campbell, P.; Cheal, B.; Tordoff, B. [Schuster Laboratory, The University of Manchester, Manchester M13 9PL (United Kingdom); Eronen, T.; Moore, I. D.; Aeystoe, J. [Department of Physics, University of Jyvaeskylae, PB 35 (YFL), FIN-40014 Jyvaeskylae (Finland)

2006-10-15T23:59:59.000Z

237

Reversible jump Markov chain Monte Carlo computation and Bayesian model determination  

E-Print Network [OSTI]

Markov chain Monte Carlo methods for Bayesian computation have until recently been restricted to problems where the joint distribution of all variables has a density with respect to some xed standard underlying measure. They have therefore not been available for application to Bayesian model determination, where the dimensionality of the parameter vector is typically not xed. This article proposes a new framework for the construction of reversible Markov chain samplers that jump between parameter subspaces of di ering dimensionality, which is exible and entirely constructive. It should therefore have wide applicability in model determination problems. The methodology is illustrated with applications to multiple change-point analysis in one and two dimensions, and toaBayesian comparison of binomial experiments.

Peter J. Green

1995-01-01T23:59:59.000Z

238

Kinetics of hydrogenation of aromatics determined by carbon-13 NMR for Athabasca bitumen-derived middle distillates  

SciTech Connect (OSTI)

High aromatics content in middle distillates is detrimental to fuel quality, as shown in such properties as smoke point of jet fuel and cetane number of diesel fuel. In the petroleum and petrochemical industries the yields from fluid catalytic cracking or steam cracking units are adversely affected by high aromatics content in the feedstock. Distillates obtained from oil sand bitumen, heavy oils, or coal liquefaction products are particularly high in aromatics. Reducing the concentration of this class of compounds is important. Aromatics hydrogenation (AHYD) is one option to achieve this result. In the current Syncrude operation a primary objective of hydrotreating is to reduce product sulfur and nitrogen contents; reducing aromatics content is an incidental result. However, the expansion plan currently under study by Syncrude includes further AHYD to improve cetane number. Predicting the product aromatics content is an important issue for this study. In the present study, hydrotreating of five Athabasca-bitumen-derived gas oils was conducted in pilot scale trickle-bed reactors using alumina-based commercial NiMo catalysts. Feedstocks originated from the distillation of virgin bitumen, and from distillates derived from treating bitumen in a fluid coker and hydrocracking pilot plant. Aromatics content was determined by the {sup 13}C NMR method. The previously developed rate equation for AHYD was modified by including power terms for space velocity and hydrogen partial pressure. The data were analyzed using the modified equation.

Yui, S.M.; Sanford, E.C. (Syncrude Canada Ltd., Edmonton, Alberta (Canada))

1987-04-01T23:59:59.000Z

239

Supersymmetric twisting of carbon nanotubes  

E-Print Network [OSTI]

We construct exactly solvable models of twisted carbon nanotubes via supersymmetry, by applying the matrix Darboux transformation. We derive the Green's function for these systems and compute the local density of states. Explicit examples of twisted carbon nanotubes are produced, where the back-scattering is suppressed and bound states are present. We find that the local density of states decreases in the regions where the bound states are localized. Dependence of bound-state energies on the asymptotic twist of the nanotubes is determined. We also show that each of the constructed unextended first order matrix systems possesses a proper nonlinear hidden supersymmetric structure with a nontrivial grading operator.

Vit Jakubsky; Mikhail S. Plyushchay

2012-02-28T23:59:59.000Z

240

Electrical and Thermal Experimental Characterization and Modeling of Carbon Nanotube/Epoxy Composites  

E-Print Network [OSTI]

The present work investigates the effect of carbon nanotube (CNT) inclusions on the electrical and thermal conductivity of a thermoset epoxy resin. The characterization of electrical and thermal conductivity of CNT/epoxy composites is presented...

Gardea, Frank

2012-10-19T23:59:59.000Z

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.


241

Micromechanics modeling of the multifunctional nature of carbon nanotube-polymer nanocomposites  

E-Print Network [OSTI]

The present work provides a micromechanics approach based on the generalized self-consistent composite cylinders method as a non-Eshelby approach towards for assessing the impact of carbon nanotubes on the multi-functional nature of nanocom...

Seidel, Gary Don

2009-06-02T23:59:59.000Z

242

Modelling the convenience yield in carbon prices using daily and realized measures  

E-Print Network [OSTI]

for carbon spot and futures prices, which are exchanged since 2005 on the European Union Emissions Trading Scheme (EU ETS). The EU emissions trading system has been created by the Directive 2003/87/CE. Across 27

Paris-Sud XI, Université de

243

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.

244

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

245

Modeling of Gas Phase Transport and Composition Evolution during the Initial Stage Sintering of Boron Carbide with Carbon Additions  

E-Print Network [OSTI]

1 Modeling of Gas Phase Transport and Composition Evolution during the Initial Stage Sintering the pores close. This process is examined using a computational model based on co-diffusion of multiple gas is to model the gas diffusion to determine the needed hold time as a function of key parameters

Matthewson, M. John

246

Enterprise Audit Modeling of Large-Scale Agencies' Energy and Carbon Dioxide Accounting  

E-Print Network [OSTI]

, and corporations as it has a broad impact on industries, societies, and global communities. The concept is extremely catchy and thus has been promoted and outside the research community. (Weidema et al, 2008) Even though carbon accounting frameworks has been... information. The economic method is more reasonable, but the cost is still limited by its planned cost savings. (Mishan & Quah, 2007) 1.3 ECA AND EEA IN DESIGN Tracking and understanding how each element in Figure 1 impacts the overall carbon total...

Wade, Brigitta Alexandra Anne

2011-12-31T23:59:59.000Z

247

Carbon monoxide in the solar atmosphere I. Numerical method and two-dimensional models  

E-Print Network [OSTI]

The radiation hydrodynamic code CO5BOLD has been supplemented with the time-dependent treatment of chemical reaction networks. Advection of particle densities due to the hydrodynamic flow field is also included. The radiative transfer is treated frequency-independently, i.e. grey, so far. The upgraded code has been applied to two-dimensional simulations of carbon monoxide (CO) in the non-magnetic solar photosphere and low chromosphere. For this purpose a reaction network has been constructed, taking into account the reactions which are most important for the formation and dissociation of CO under the physical conditions of the solar atmosphere. The network has been strongly reduced to 27 reactions, involving the chemical species H, H2, C, O, CO, CH, OH, and a representative metal. The resulting CO number density is highest in the cool regions of the reversed granulation pattern at mid-photospheric heights and decreases strongly above. There, the CO abundance stays close to a value of 8.3 on the usual logarithmic abundance scale with [H]=12 but is reduced in hot shock waves which are a ubiquitous phenomenon of the model atmosphere. For comparison, the corresponding equilibrium densities have been calculated, based on the reaction network but also under assumption of instantaneous chemical equilibrium by applying the Rybicki & Hummer (RH) code by Uitenbroek (2001). Owing to the short chemical timescales, the assumption holds for a large fraction of the atmosphere, in particular the photosphere. In contrast, the CO number density deviates strongly from the corresponding equilibrium value in the vicinity of chromospheric shock waves. Simulations with altered reaction network clearly show that the formation channel via hydroxide (OH) is the most important one under the conditions of the solar atmosphere.

S. Wedemeyer-Boehm; I. Kamp; J. Bruls; B. Freytag

2005-03-23T23:59:59.000Z

248

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

SciTech Connect (OSTI)

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

249

Modelled effects of precipitation on ecosystem carbon and water dynamics in different climatic zones  

SciTech Connect (OSTI)

The ongoing changes in the global climate expose the world s ecosystems not only to increasing CO2 concentrations and temperatures but also to altered precipitation (P) regimes. Using four well-established process-based ecosystem models (LPJ, DayCent, ORCHIDEE, TECO), we explored effects of potential P changes on water limitation and net primary production (NPP) in seven terrestrial ecosystems with distinctive vegetation types in different hydroclimatic zones. We found that NPP responses to P changes differed not only among sites but also within a year at a given site. The magnitudes of NPP change were basically determined by the degree of ecosystem water limitation, which was quantified here using the ratio between atmospheric transpirational demand and soil water supply. Humid sites and/or periods were least responsive to any change in P as compared with moderately humid or dry sites/periods. We also found that NPP responded more strongly to doubling or halving of P amount and a seasonal shift in P occurrence than that to altered P frequency and intensity at constant annual amounts. The findings were highly robust across the four models especially in terms of the direction of changes and largely consistent with earlier P manipulation experiments and modelling results. Overall, this study underscores the widespread importance of P as a driver of change in ecosystems, although the ultimate response of a particular site will depend on the detailed nature and seasonal timing of P change.

Gerten, Dieter [Potsdam Institute for Climate Impact Research, Potsdam, Germany; Luo, Yiqi [University of Oklahoma; Le Maire, Guerric [Laboratoire des Sciences du Climat et de l'Environement, France; Parton, William [University of Colorado, Fort Collins; Keough, Cindy [University of Colorado, Fort Collins; Weng, Ensheng [University of Oklahoma, Norman; Beier, Claus [Riso National Laboratory, Roskilde, Denmark; Ciais, Philippe [Laboratoire des Sciences du Climat et de l'Environement, France; Cramer, Wolfgang [Potsdam Institute for Climate Impact Research, Potsdam, Germany; Dukes, Jeff [University of Massachusetts, Boston; Hanson, Paul J [ORNL; Knapp, Alan [Colorado State University, Fort Collins; Linder, Sune [Swedish University of Agricultural Sciences, Upsalla, Sweden; Nepstad, Daniel [Woods Hole Oceanographic Institution (WHOI), Woods Hole, MA; Rustad, Lindsey [USDA Forest Service; Sowerby, ALWYN [Centre for Ecology and Hydrology, Bangor, Gwynedd, United Kingdom

2008-01-01T23:59:59.000Z

250

The identification of HCN and HNC in Carbon Stars: Model Atmospheres, Synthetic Spectra and Fits to Observations in the 2.7-4.0 micron Region  

E-Print Network [OSTI]

Model carbon star atmospheres and synthetic spectra have been calculated using the recent HCN/HNC vibration rotation linelist of Harris et al. (2002) ApJ, 578, 657. The calculations are repeated using only HCN lines and show that HNC has a significant effect upon the temperature, density and optical depth of a stellar atmosphere. We fit synthetic spectra in the 2.7-4.0 micron region to observed ISO spectra of the carbon stars WZ Cas and TX Psc obtained by Aoki et al. (1998), A&A, 340, 222. These fits allow us to identify absorption by HNC in the spectrum of WZ Cas at 2.8-2.9 microns, and to determine new independent estimates of effective temperature and log(Nc)/log(No). The findings reported here indicate that absorption by both HCN and HNC is needed to fully explain the observed stellar spectra and represent the first identification of HNC in a star. Q branch absorption by the HCN $\\Delta v_2=1$, $\\Delta v_3=1$ and $\\Delta v_1=1$, $\\Delta v_2=-1$ bands at 3.55 and 3.86 microns respectively, are identified in the spectrum of WZ Cas.

G. J. Harris; Ya. V. Pavlenko; H. R. A. Jones; J. Tennyson

2003-06-06T23:59:59.000Z

251

EXPERIMENTAL DESIGN APPLICATIONS FOR MODELING AND ASSESSING CARBON DIOXIDE SEQUESTRATION IN SALINE AQUIFERS  

SciTech Connect (OSTI)

This project was a computer modeling effort to couple reservoir simulation and ED/RSM using Sensitivity Analysis, Uncertainty Analysis, and Optimization Methods, to assess geologic, geochemical, geomechanical, and rock-fluid effects and factors on CO2 injectivity, capacity, and plume migration. The project objective was to develop proxy models to simplify the highly complex coupled geochemical and geomechanical models in the utilization and storage of CO2 in the subsurface. The goals were to investigate and prove the feasibility of the ED/RSM processes and engineering development, and bridge the gaps regarding the uncertainty and unknowns of the many geochemical and geomechanical interacting parameters in the development and operation of anthropogenic CO2 sequestration and storage sites. The bottleneck in this workflow is the high computational effort of reactive transport simulation models and large number of input variables to optimize with ED/RSM techniques. The project was not to develop the reactive transport, geomechanical, or ED/RSM software, but was to use what was commercially and/or publically available as a proof of concept to generate proxy or surrogate models. A detailed geologic and petrographic mineral assemblage and geologic structure of the doubly plunging anticline was defined using the USDOE RMOTC formations of interest data (e.g., Lower Sundance, Crow Mountain, Alcova Limestone, and Red Peak). The assemblage of 23 minerals was primarily developed from literature data and petrophysical (well log) analysis. The assemblage and structure was input into a commercial reactive transport simulator to predict the effects of CO2 injection and complex reactions with the reservoir rock. Significant impediments were encountered during the execution phase of the project. The only known commercial reactive transport simulator was incapable of simulating complex geochemistry modeled in this project. Significant effort and project funding was expended to determine the limitations of both the commercial simulator and the Lawrence Berkeley National Laboratory (LBNL) R&D simulator, TOUGHREACT available to the project. A simplified layer cake model approximating the volume of the RMOTC targeted reservoirs was defined with 1-3 minerals eventually modeled with limited success. Modeling reactive transport in porous media requires significant computational power. In this project, up to 24 processors were used to model a limited mineral set of 1-3 minerals. In addition, geomechanical aspects of injecting CO2 into closed, semi-open, and open systems in various well completion methods was simulated. Enhanced Oil Recovery (EOR) as a storage method was not modeled. A robust and stable simulation dataset or base case was developed and used to create a master dataset with embedded instructions for input to the ED/RSM software. Little success was achieved toward the objective of the project using the commercial simulator or the LBNL simulator versions available during the time of this project. Several hundred realizations were run with the commercial simulator and ED/RSM software, most having convergence problems and terminating prematurely. A proxy model for full field CO2 injection sequestration utilization and storage was not capable of being developed with software available for this project. Though the chemistry is reasonably known and understood, based on the amount of effort and huge computational time required, predicting CO2 sequestration storage capacity in geologic formations to within the program goals of 30% proved unsuccessful.

Rogers, John

2014-08-31T23:59:59.000Z

252

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

SciTech Connect (OSTI)

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.

Cohen, Warren [USDA Forest Service] [USDA Forest Service

2014-07-03T23:59:59.000Z

253

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 (OSTI)

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

254

Assimilation of satellite reflecance dataa into a dynamical leaf model to infer seasonally varying leaf area for climate and carbon models  

SciTech Connect (OSTI)

Leaf area index is an important input for many climate and carbon models. The widely used leaf area products derived from satellite-observed surface reflectances contain substantial erratic fluctuations in time due to inadequate atmospheric corrections and observational and retrieval uncertainties. These fluctuations are inconsistent with the seasonal dynamics of leaf area, known to be gradual. Their use in process-based terrestrial carbon models corrupts model behavior, making diagnosis of model performance difficult. We propose a data assimilation approach that combines the satellite observations of Moderate Resolution Imaging Spectroradiometer (MODIS) albedo with a dynamical leaf model. Its novelty is that the seasonal cycle of the directly retrieved leaf areas is smooth and consistent with both observations and current understandings of processes controlling leaf area dynamics. The approach optimizes the dynamical model parameters such that the difference between the estimated surface reflectances based on the modeled leaf area and those of satellite observations is minimized. We demonstrate the usefulness and advantage of our new approach at multiple deciduous forest sites in the United States.

Liu, Qing [Georgia Institute of Technology; Gu, Lianhong [ORNL; Dickinson, Robert E. [Georgia Institute of Technology; Tian, Y [Georgia Institute of Technology; Zhou, L [Georgia Institute of Technology; Post, Wilfred M [ORNL

2007-01-01T23:59:59.000Z

255

Combustion modeling of mono-carbon fuels using the rate-controlled constrained-equilibrium method  

SciTech Connect (OSTI)

The rate-controlled constrained-equilibrium (RCCE) method for simplifying the kinetics of complex reacting systems is reviewed. This method is based on the maximum entropy principle of thermodynamics and involves the assumption that the evolution of a system can be described using a relatively small set of slowly changing constraints imposed by the external and internal dynamics of the system. As a result, the number of differential and algebraic equations required to determine the constrained-equilibrium state of a system can be very much smaller than the number of species in the system. It follows that only reactions which change constraints are required to determine the dynamic evolution of the system and all other reactions are in equilibrium. The accuracy of the method depends on both the character and number of constraints employed and issues involved in the selection and transformation of the constraints are discussed. A method for determining the initial conditions for highly non-equilibrium systems is also presented. The method is illustrated by applying it to the oxidation of methane (CH{sub 4}), methanol (CH{sub 3}OH), and formaldehyde (CH{sub 2}O) in a constant volume adiabatic chamber over a wide range of initial temperatures, pressures, and equivalence ratios. The RCCE calculations were carried out using 8-12 constraints and 133 reactions. Good agreement with ''Detailed Kinetic Model'' (DMK) calculations using 29 species and 133 reactions was obtained. The number of reactions in the RCCE calculations could be reduced to 20 for CH{sub 4}, 16 for CH{sub 3}OH, and 12 for CH{sub 2}O without changing the results significantly affecting the agreement. It may be noted that a DKM with 29 species requires a minimum of 29 reactions. (author)

Janbozorgi, Mohammad; Ugarte, Sergio; Metghalchi, Hameed [Mechanical and Industrial Engineering Department, Northeastern University, Boston, MA 02115 (United States); Keck, James. C. [Mechanical Engineering Department, Massachusetts Institute of Technology, Cambridge, MA 02139 (United States)

2009-10-15T23:59:59.000Z

256

Determinant representation of correlation functions for the U{sub q}(gl(1 vertical bar 1)) free Fermion model  

SciTech Connect (OSTI)

With the help of the factorizing F-matrix, the scalar products of the U{sub q}(gl(1 vertical bar 1)) free fermion model are represented by determinants. By means of these results, we obtain the determinant representations of correlation functions of the model.

Zhao Shaoyou; Yang Wenli; Zhang Yaozhong [Department of Mathematics, University of Queensland, Brisbane, QLD 4072 (Australia); Department of Physics, Beijing Institute of Technology, Beijing 100081 (China); Department of Mathematics, University of Queensland, Brisbane, QLD 4072 (Australia); Institute of Modern Physics, Northwest University, Xian 710069 (China); Department of Mathematics, University of Queensland, Brisbane, QLD 4072 (Australia)

2006-01-15T23:59:59.000Z

257

CX-001459: Categorical Exclusion Determination | Department of...  

Broader source: Energy.gov (indexed) [DOE]

Categorical Exclusion Determination CX-001459: Categorical Exclusion Determination Air Quality VIII: An International Conference on Carbon Management, Mercury, Trace Elements,...

258

CX-012136: Categorical Exclusion Determination | Department of...  

Broader source: Energy.gov (indexed) [DOE]

Exclusion Determination CX-012136: Categorical Exclusion Determination Distributed Fiber Optic Arrays: Integrated Temperature and Seismic Sensing for Detection of Carbon...

259

CX-011016: Categorical Exclusion Determination | Department of...  

Broader source: Energy.gov (indexed) [DOE]

Exclusion Determination CX-011016: Categorical Exclusion Determination Distributed Fiber Optic Arrays: Integrated Temperature and Seismic Sensing for Detection of Carbon...

260

CX-011013: Categorical Exclusion Determination | Department of...  

Broader source: Energy.gov (indexed) [DOE]

Exclusion Determination CX-011013: Categorical Exclusion Determination Distributed Fiber Optic Arrays: Integrated Temperature and Seismic Sensing for Detection of Carbon...

Note: This page contains sample records for the topic "determination modeling carbon" from the National Library of EnergyBeta (NLEBeta).
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We encourage you to perform a real-time search of NLEBeta
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261

CX-011017: Categorical Exclusion Determination | Department of...  

Broader source: Energy.gov (indexed) [DOE]

Exclusion Determination CX-011017: Categorical Exclusion Determination Distributed Fiber Optic Arrays: Integrated Temperature and Seismic Sensing for Detection of Carbon...

262

The thin section rock physics: Modeling and measurement of seismic wave velocity on the slice of carbonates  

SciTech Connect (OSTI)

This paper discusses a new approach for investigating the seismic wave velocity of rock, specifically carbonates, as affected by their pore structures. While the conventional routine of seismic velocity measurement highly depends on the extensive laboratory experiment, the proposed approach utilizes the digital rock physics view which lies on the numerical experiment. Thus, instead of using core sample, we use the thin section image of carbonate rock to measure the effective seismic wave velocity when travelling on it. In the numerical experiment, thin section images act as the medium on which wave propagation will be simulated. For the modeling, an advanced technique based on artificial neural network was employed for building the velocity and density profile, replacing image's RGB pixel value with the seismic velocity and density of each rock constituent. Then, ultrasonic wave was simulated to propagate in the thin section image by using finite difference time domain method, based on assumption of an acoustic-isotropic medium. Effective velocities were drawn from the recorded signal and being compared to the velocity modeling from Wyllie time average model and Kuster-Toksoz rock physics model. To perform the modeling, image analysis routines were undertaken for quantifying the pore aspect ratio that is assumed to represent the rocks pore structure. In addition, porosity and mineral fraction required for velocity modeling were also quantified by using integrated neural network and image analysis technique. It was found that the Kuster-Toksoz gives the closer prediction to the measured velocity as compared to the Wyllie time average model. We also conclude that Wyllie time average that does not incorporate the pore structure parameter deviates significantly for samples having more than 40% porosity. Utilizing this approach we found a good agreement between numerical experiment and theoretically derived rock physics model for estimating the effective seismic wave velocity of rock.

Wardaya, P. D., E-mail: pongga.wardaya@utp.edu.my; Noh, K. A. B. M., E-mail: pongga.wardaya@utp.edu.my; Yusoff, W. I. B. W., E-mail: pongga.wardaya@utp.edu.my [Petroleum Geosciences Department, Universiti Teknologi PETRONAS, Tronoh, Perak, 31750 (Malaysia); Ridha, S. [Petroleum Engineering Department, Universiti Teknologi PETRONAS, Tronoh, Perak, 31750 (Malaysia); Nurhandoko, B. E. B. [Wave Inversion and Subsurface Fluid Imaging Research Laboratory (WISFIR), Dept. of Physics, Institute of Technology Bandung, Bandung, Indonesia and Rock Fluid Imaging Lab, Bandung (Indonesia)

2014-09-25T23:59:59.000Z

263

Causes and implications of persistent atmospheric carbon dioxide biases in Earth System Models  

E-Print Network [OSTI]

2013), The Community Earth System Model: A framework forsimu- lations from 15 Earth System Models (ESMs) Most ESMsdioxide biases in Earth System Models, J. Geophys. Res.

2014-01-01T23:59:59.000Z

264

Causes of variation in soil carbon simulations from CMIP5 Earth system models and comparison with observations  

E-Print Network [OSTI]

and capture more of the spa- tial variation in soil carbon.carbon stocks (Table 3). ESMs varied in their ability to capture

2013-01-01T23:59:59.000Z

265

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

266

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

SciTech Connect (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

267

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

E-Print Network [OSTI]

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...

Chapman, Ian

2012-10-19T23:59:59.000Z

268

anchored carbon fiber: Topics by E-print Network  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

material. It is important that a carbon fiber manufacturing cost model 4 Carbon Fiber Composite Cellular A Dissertation Materials Science Websites Summary: Carbon Fiber Composite...

269

Yucca Mountain Area Saturated Zone Dissolved Organic Carbon Isotopic Data  

SciTech Connect (OSTI)

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

270

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

SciTech Connect (OSTI)

GOAL: To develop and apply an approach to quantify and understand the regional carbon balance of the west coast states for the North American Carbon Program. OBJECTIVE: 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. APPROACH: In performing the regional analysis, the research plan for the bottom-up approach uses a nested hierarchy of observations that include AmeriFlux data (i.e., net ecosystem exchange (NEE) from eddy covariance and associated biometric data), intermediate intensity inventories from an extended plot array partially developed from the PI's previous research, Forest Service FIA and CVS inventory data, time since disturbance, disturbance type, and cover type from Landsat developed in this study, and productivity estimates from MODIS algorithms. The BIOME-BGC model is used to integrate information from these sources and quantify C balance across the region. The inverse modeling approach assimilates flux data from AmeriFlux sites, high precision CO2 concentration data from AmeriFlux towers and four new calibrated CO2 sites, reanalysis meteorology and various remote sensing products to generate statewide estimates of biosphere carbon exchange from the atmospheric point of view.

B.E. Law; D. Turner; M. Goeckede

2010-06-01T23:59:59.000Z

271

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

SciTech Connect (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

272

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...

Guarneri, Christine E.

2011-08-08T23:59:59.000Z

273

CX-000591: Categorical Exclusion Determination | Department of...  

Broader source: Energy.gov (indexed) [DOE]

Exclusion Determination 25A2936 - Carbon Nanotube Membranes for Energy-Efficient Carbon Sequestration CX(s) Applied: B3.6 Date: 12152009 Location(s): California...

274

A model for determining shelf life, estimating terminal body composition, yield grade and quality grade of feedlot cattle  

E-Print Network [OSTI]

as to style and content by: F. M. Byers (Chairman of Co m ttee) James McGrann (Member) ~&~& G. T. Schelling (Member) December 1986 ABSRACT A Model for Determining Shelf Life, Estimating Terminal Body Composition, Yield Grade and Quality Grade... of Feedlot Cattle. (December 1985) Richard Jay Perry, B, S. , Texas AlkM University Chairman of Advisory Committee: Dr. F, M. Byers A model for determining shelf life and estimating carcass fat (kg), yield grade and quality grade was developed. Shelf...

Perry, Richard Jay

1985-01-01T23:59:59.000Z

275

Dynamical coupled-channels model of $K^- p$ reactions (I): Determination of partial-wave amplitudes  

E-Print Network [OSTI]

We develop a dynamical coupled-channels model of K^- p reactions, aiming at extracting the parameters associated with hyperon resonances and providing the elementary antikaon-nucleon scattering amplitudes that can be used for investigating various phenomena in the strangeness sector such as the production of hypernuclei from kaon-nucleus reactions. The model consists of (a) meson-baryon (MB) potentials v_{M'B',MB} derived from the phenomenological SU(3) Lagrangian, and (b) vertex interactions Gamma_{MB,Y*} for describing the decays of the bare excited hyperon states (Y*) into MB states. The model is defined in a channel space spanned by the two-body barK N, pi Sigma, pi Lambda, eta Lambda, and K Xi states and also the three-body pi pi Lambda and pi barK N states that have the resonant pi Sigma* and barK* N components, respectively. The resulting coupled-channels scattering equations satisfy the multichannel unitarity conditions and account for the dynamical effects arising from the off-shell rescattering processes. The model parameters are determined by fitting the available data of the unpolarized and polarized observables of the K^- p --> barK N, pi Sigma, pi Lambda, eta Lambda, K Xi reactions in the energy region from the threshold to invariant mass W=2.1 GeV. Two models with equally good chi^2 fits to the data have been constructed. The partial-wave amplitudes obtained from the constructed models are compared with the results from a recent partial-wave analysis by the Kent State University group. We discuss the differences between these three analysis results. Our results at energies near the threshold suggest that the higher partial waves should be treated on the same footing as the S wave if one wants to understand the nature of Lambda(1405)1/2^- using the data below the barK N threshold, as will be provided by the J-PARC E31 experiment.

H. Kamano; S. X. Nakamura; T. -S. H. Lee; T. Sato

2014-12-12T23:59:59.000Z

276

Carbon taxes and India  

SciTech Connect (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

277

Carbon in detonations  

SciTech Connect (OSTI)

We review three principal results from a five year study of carbon and its properties in detonations and discuss the implications of these results to the behavior of explosives. We first present a new determination of the carbon melt line from release wave velocity measurements in the shocked state. We then outline a colloidal theory of carbon clustering which from diffusion limited coagulation predicts a slow energy release rate for the carbon chemistry. Finally, we show the results from the examination of recovered soot. Here we see support for the colloid theory and find the diamond phase of carbon. The main theme of this paper is that the carbon in detonation products is in the form of a colloidal suspension of carbon clusters which grow through diffusion limited collisions. Even the final state is not bulk graphite or diamond, but is a collection of small, less than 100 /angstrom/A, diamond and graphitic clusters. 23 refs., 4 figs.

Johnson, J.D.

1989-01-01T23:59:59.000Z

278

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

SciTech Connect (OSTI)

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

279

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

SciTech Connect (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

280

Fractal model for estimating fracture toughness of carbon nanotube reinforced aluminum oxide  

SciTech Connect (OSTI)

The current work focuses on predicting the fracture toughness of Al{sub 2}O{sub 3} ceramic matrix composites using a modified Mandelbrot's fractal approach. The first step confirms that the experimental fracture toughness values fluctuate within the fracture toughness range predicted as per the modified fractal approach. Additionally, the secondary reinforcements [such as carbon nanotubes (CNTs)] have shown to enhance the fracture toughness of Al{sub 2}O{sub 3}. Conventional fractural toughness evaluation via fractal approach underestimates the fracture toughness by considering the shortest crack path. Hence, the modified Mandelbrot's fractal approach considers the crack propagation along the CNT semicircumferential surface (three-dimensional crack path propagation) for achieving an improved fracture toughness estimation of Al{sub 2}O{sub 3}-CNT composite. The estimations obtained in the current approach range within 4% error regime of the experimentally measured fracture toughness values of the Al{sub 2}O{sub 3}-CNT composite.

Rishabh, Abhishek; Joshi, Milind R.; Balani, Kantesh [Department of Materials and Metallurgical Engineering, Indian Institute of Technology Kanpur, Kanpur 208016 (India)

2010-06-15T23:59:59.000Z

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.


281

Carbonic Acid Pretreatment of Biomass  

SciTech Connect (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 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

282

Model ecosystem determination of the metabolic and environmental fate of tetrachloro-DDT  

SciTech Connect (OSTI)

A potential hazardous waste site investigation was conducted by the Environmental Protection Agency to determine whether ground water, surface water, or area soils and sediments were contaminated as a result of waster water discharges or improper solid waste disposal practices of a pesticide manufacturer. One of the compounds discharged into the environment was 1,1,1,2-tetrachloro-2,2-bis(p-chlorophenyl)ethane, commonly referred to as tetrachloro-DDT. Unlike a great many of the DDT analogs, tetrachloro-DDT has come under only limited scrutiny, mainly because it was dismissed as having poor insecticidal properties relative to DDT and other analogs. Its metabolism in ingesting organisms, and degradative pathways in the environment have consequently been left uncertain. This model ecosystem study was undertaken to examine the unanswered questions concerning the metabolic and environmental fate of tetrachloro-DDT. The relevance of this study pertains to disposal practices of pesticide manufacturers who use tetrachloro-DDT as a product precursor.

Cole, R.B.; Metcalf, R.L.

1987-01-01T23:59:59.000Z

283

ReaxFF Study of the Oxidation of Lignin Model Compounds for the Most Common Linkages in Softwood in View of Carbon Fiber Production  

SciTech Connect (OSTI)

Lignin is an underused but major component of biomass. One possible area of utilization is the production of carbon fiber. A necessary processing step is the stabilization of lignin fiber (typically in an oxygen environment) before high temperature treatment. We investigate oxidative, thermal conversion of lignin using computational methods. Dilignol model compounds for the most common (seven) linkages in softwood are chosen to represent the diverse structure of lignin. We perform molecular dynamics simulation where the potential energy surface is described by a reactive force field (ReaxFF). We calculate overall activation energies for model conversion and reveal initial mechanisms of formaldehyde formation. We record fragmentation patterns and average carbon oxidation numbers at various temperatures. Most importantly, we identify mechanisms for stabilizing reactions that result in cyclic, and rigid connections in softwood lignin fibers that are necessary for further processing into carbon fibers.

Beste, Ariana [ORNL] [ORNL

2014-01-01T23:59:59.000Z

284

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

SciTech Connect (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

285

A Sensitivity Study on Modeling Black Carbon in Snow and its Radiative Forcing over the Arctic and Northern China  

SciTech Connect (OSTI)

Black carbon in snow (BCS) simulated in the Community Atmosphere Model (CAM5) is evaluated against measurements over Northern China and the Arctic, and its sensitivity to atmospheric deposition and two parameters that affect post-depositional enrichment is explored. The BCS concentration is overestimated (underestimated) by a factor of two in Northern China (Arctic) in the default model, but agreement with observations is good over both regions in the simulation with improvements in BC transport and deposition. Sensitivity studies indicate that uncertainty in the melt-water scavenging efficiency (MSE) parameter substantially affects BCS and its radiative forcing (by a factor of 2-7) in the Arctic through post-depositional enrichment. The MSE parameter has a relatively small effect on the magnitude of BCS seasonal cycle but can alter its phase in Northern China. The impact of the snow aging scaling factor (SAF) on BCS, partly through the post-depositional enrichment effect, shows more complex latitudinal and seasonal dependence. Similar to MSE, SAF affects more significantly the magnitude (phase) of BCS season cycle over the Arctic (Northern China). While uncertainty associated with the representation of BC transport and deposition processes in CAM5 is more important than that associated with the two snow model parameters in Northern China, the two uncertainties have comparable effect in the Arctic.

Qian, Yun; Wang, Hailong; Zhang, Rudong; Flanner, M. G.; Rasch, Philip J.

2014-06-02T23:59:59.000Z

286

Modelled Black Carbon Radiative Forcing and Atmospheric Lifetime in AeroCom Phase II Constrained by Aircraft Observations  

SciTech Connect (OSTI)

Black carbon (BC) aerosols absorb solar radiation, and are generally held to exacerbate global warming through exerting a positive radiative forcing1. However, the total contribution of BC to the ongoing changes in global climate is presently under debate2-8. Both anthropogenic BC emissions and the resulting spatial and temporal distribution of BC concentration are highly uncertain2,9. In particular, long range transport and processes affecting BC atmospheric lifetime are poorly understood, leading to large estimated uncertainty in BC concentration at high altitudes and far from emission sources10. These uncertainties limit our ability to quantify both the historical, present and future anthropogenic climate impact of BC. Here we compare vertical profiles of BC concentration from four recent aircraft measurement campaigns with 13 state of the art aerosol models, and show that recent assessments may have overestimated present day BC radiative forcing. Further, an atmospheric lifetime of BC of less than 5 days is shown to be essential for reproducing observations in transport dominated remote regions. Adjusting model results to measurements in remote regions, and at high altitudes, leads to a 25% reduction in the multi-model median direct BC forcing from fossil fuel and biofuel burning over the industrial era.

Samset, B. H.; Myhre, G.; Herber, Andreas; Kondo, Yutaka; Li, Shao-Meng; Moteki, N.; Koike, Makoto; Oshima, N.; Schwarz, Joshua P.; Balkanski, Y.; Bauer, S.; Bellouin, N.; Berntsen, T.; Bian, Huisheng; Chin, M.; Diehl, Thomas; Easter, Richard C.; Ghan, Steven J.; Iversen, T.; Kirkevag, A.; Lamarque, Jean-Francois; Lin, Guang; Liu, Xiaohong; Penner, Joyce E.; Schulz, M.; Seland, O.; Skeie, R. B.; Stier, P.; Takemura, T.; Tsigaridis, Kostas; Zhang, Kai

2014-11-27T23:59:59.000Z

287

Vehicle Technologies Office Merit Review 2014: Validation of Material Models for Automotive Carbon Fiber Composite Structures  

Broader source: Energy.gov [DOE]

Presentation given by General Motors at 2014 DOE Hydrogen and Fuel Cells Program and Vehicle Technologies Office Annual Merit Review and Peer Evaluation Meeting about validation of material models...

288

Modeled Interactive Effects of Precipitation, temperature, and [CO2] on Ecosystem Carbon and Water Dynamics in Different Climatic Zones  

SciTech Connect (OSTI)

Interactive effects of multiple global change factors on ecosystem processes are complex. It is relatively expensive to explore those interactions in manipulative experiments. We conducted a modeling analysis to identify potentially important interactions and to stimulate hypothesis formulation for experimental research. Four models were used to quantify interactive effects of climate warming (T), altered precipitation amounts [doubled (DP) and halved (HP)] and seasonality (SP, moving precipitation in July and August to January and February to create summer drought), and elevated [CO2] (C) on net primary production (NPP), heterotrophic respiration (Rh), net ecosystem production (NEP), transpiration, and runoff.We examined those responses in seven ecosystems, including forests, grasslands, and heathlands in different climate zones. The modeling analysis showed that none of the threeway interactions among T, C, and altered precipitation was substantial for either carbon or water processes, nor consistent among the seven ecosystems. However, two-way interactive effects on NPP, Rh, and NEP were generally positive (i.e. amplification of one factor s effect by the other factor) between T and C or between T and DP. A negative interaction (i.e. depression of one factor s effect by the other factor) occurred for simulated NPP between T and HP. The interactive effects on runoff were positive between T and HP. Four pairs of two-way interactive effects on plant transpiration were positive and two pairs negative. In addition, wet sites generally had smaller relative changes in NPP, Rh, runoff, and transpiration but larger absolute changes in NEP than dry sites in response to the treatments. The modeling results suggest new hypotheses to be tested in multifactor global change experiments. Likewise, more experimental evidence is needed for the further improvement of ecosystem models in order to adequately simulate complex interactive processes.

Luo, Yiqi [University of Oklahoma; Gerten, Dieter [Potsdam Institute for Climate Impact Research, Potsdam, Germany; Le Maire, Guerric [Laboratoire des Sciences du Climat et de l'Environement, France; Parton, William [University of Colorado, Fort Collins; Weng, Ensheng [University of Oklahoma, Norman; Zhou, Xuhuui [University of Oklahoma; Keough, Cindy [University of Colorado, Fort Collins; Beier, Claus [Riso National Laboratory, Roskilde, Denmark; Ciais, Philippe [Laboratoire des Sciences du Climat et de l'Environement, France; Cramer, Wolfgang [Potsdam Institute for Climate Impact Research, Potsdam, Germany; Dukes, Jeff [University of Massachusetts, Boston; Emmett, Bridget [Centre for Ecology and Hydrology, Bangor, Gwynedd, United Kingdom; Hanson, Paul J [ORNL; Knapp, Alan [Colorado State University, Fort Collins; Linder, Sune [Swedish University of Agricultural Sciences, Upsalla, Sweden; Nepstad, Daniel [Woods Hole Oceanographic Institution (WHOI), Woods Hole, MA; Rustad, Lindsey [USDA Forest Service

2008-01-01T23:59:59.000Z

289

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

290

Using NASA Remote Sensing Data to Reduce Uncertainty of Land-Use Transitions in Global Carbon-Climate Models: Data Management Plan  

E-Print Network [OSTI]

-use transitions and their inherent uncertainty. Our plan for managing these datasets includes quality assessmentUsing NASA Remote Sensing Data to Reduce Uncertainty of Land-Use Transitions in Global Carbon-Climate Models: Data Management Plan L. Chini, G.C. Hurtt, M. Hansen, and P. Potapov Department of Geography

291

Economic and Physical Modeling of Land Use in GCAM 3.0 and an Application to Agricultural Productivity, Land, and Terrestrial Carbon  

SciTech Connect (OSTI)

We explore the impact of changes in agricultural productivity on global land use and terrestrial carbon using the new agriculture and land use modeling approach developed for Global Change Assessment Model (GCAM) version 3.0. This approach models economic land use decisions with regional, physical, and technological specificity while maintaining economic and physical integration with the rest of the GCAM model. Physical land characteristics and quantities are tracked explicitly, and crop production practices are modeled discretely to facilitate coupling with physical models. Economic land allocation is modeled with non-linear functions in a market equilibrium rather than through a constrained optimization. In this paper, we explore three scenarios of future agriculture productivity in all regions of the globe over this century, ranging from a high growth to a zero growth level. The higher productivity growth scenario leads to lower crop prices, increased production of crops in developing nations, preservation of global forested lands and lower terrestrial carbon emissions. The scenario with no productivity improvement results in higher crop prices, an expansion of crop production in the developed world, loss of forested lands globally, and higher terrestrial carbon emissions.

Wise, Marshall A.; Calvin, Katherine V.; Kyle, G. Page; Luckow, Patrick; Edmonds, James A.

2014-09-01T23:59:59.000Z

292

Review of models used for determining consequences of UF{sub 6} release: Development of model evaluation criteria. Volume 1  

SciTech Connect (OSTI)

The objective of this study is to examine the usefulness and effectiveness of currently existing models that simulate the release of uranium hexafluoride from UF{sub 6}-handling facilities, subsequent reactions of UF{sub 6} with atmospheric moisture, and the dispersion of UF{sub 6} and reaction products in the atmosphere. The study evaluates screening-level and detailed public-domain models that were specifically developed for UF{sub 6} and models that were originally developed for the treatment of dense gases but are applicable to UF{sub 6} release, reaction, and dispersion. The model evaluation process is divided into three specific tasks: model-component evaluation; applicability evaluation; and user interface and quality assurance and quality control (QA/QC) evaluation. Within the model-component evaluation process, a model`s treatment of source term, thermodynamics, and atmospheric dispersion are considered and model predictions are compared with actual observations. Within the applicability evaluation process, a model`s applicability to Integrated Safety Analysis, Emergency Response Planning, and Post-Accident Analysis, and to site-specific considerations are assessed. Finally, within the user interface and QA/QC evaluation process, a model`s user-friendliness, presence and clarity of documentation, ease of use, etc. are assessed, along with its handling of QA/QC. This document presents the complete methodology used in the evaluation process.

Nair, S.K.; Chambers, D.B.; Park, S.H.; Hoffman, F.O. [Senes Oak Ridge, Inc., TN (United States). Center for Risk Analysis

1997-11-01T23:59:59.000Z

293

Carbon Capture  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Carbon Capture Pre-Combustion Post-Combustion CO2 Compression Systems Analysis Regulatory Drivers Program Plan Capture Handbook Carbon capture involves the separation of CO2 from...

294

Edinburgh Research Explorer Modelling Urban scale Retrofit, Pathways to 2050 Low Carbon  

E-Print Network [OSTI]

electricity consumption in Wales with power generated from renewable sources by 2025 (WAG, 2009) which would to engage with the modelling process. INTRODUCTION The UK government has set an ambitious target of 80 retrofit design process need to be researched further. The Welsh Government have committed to achieving

Millar, Andrew J.

295

Carbon and Nitrogen Dynamics in Agricultural Soils  

E-Print Network [OSTI]

support in a precision farming context. Keywords: Carbon balances, carbon sequestration, decompositionCarbon 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

296

Study of behavior and determination of customer lifetime value(CLV) using Markov chain model  

SciTech Connect (OSTI)

Customer Lifetime Value or CLV is a restriction on interactive marketing to help a company in arranging financial for the marketing of new customer acquisition and customer retention. Additionally CLV can be able to segment customers for financial arrangements. Stochastic models for the fairly new CLV used a Markov chain. In this model customer retention probability and new customer acquisition probability play an important role. This model is originally introduced by Pfeifer and Carraway in 2000 [1]. They introduced several CLV models, one of them only involves customer and former customer. In this paper we expand the model by adding the assumption of the transition from former customer to customer. In the proposed model, the CLV value is higher than the CLV value obtained by Pfeifer and Caraway model. But our model still requires a longer convergence time.

Permana, Dony, E-mail: donypermana@students.itb.ac.id [Statistics Research Division, Faculty of Mathematics and Natural Science, Bandung Institute of Technology, Indonesia and Statistics Study Program, Faculty of Mathematics and Natural Sciences, Padang State University (Indonesia); Indratno, Sapto Wahyu; Pasaribu, Udjianna S. [Statistics Research Division, Faculty of Mathematics and Natural Science, Bandung Institute of Technology (Indonesia)

2014-03-24T23:59:59.000Z

297

Geosynchronous orbit determination using space surveillance network observations and improved radiative force modeling  

E-Print Network [OSTI]

Correct modeling of the space environment, including radiative forces, is an important aspect of space situational awareness for geostationary (GEO) spacecraft. Solar radiation pressure has traditionally been modeled using ...

Lyon, Richard Harry, 1981-

2004-01-01T23:59:59.000Z

298

Review of models used for determining consequences of UF{sub 6} release: Model evaluation report. Volume 2  

SciTech Connect (OSTI)

Three uranium hexafluoride-(UF{sub 6}-) specific models--HGSYSTEM/UF{sub 6}, Science Application International Corporation, and RTM-96; three dense-gas models--DEGADIS, SLAB, and the Chlorine Institute methodology; and one toxic chemical model--AFTOX--are evaluated on their capabilities to simulate the chemical reactions, thermodynamics, and atmospheric dispersion of UF{sub 6} released from accidents at nuclear fuel-cycle facilities, to support Integrated Safety Analysis, Emergency Response Planning, and Post-Accident Analysis. These models are also evaluated for user-friendliness and for quality assurance and quality control features, to ensure the validity and credibility of the results. Model performance evaluations are conducted for the three UF{sub 6}-specific models, using field data on releases of UF{sub 6} and other heavy gases. Predictions from the HGSYSTEM/UF{sub 6} and SAIC models are within an order of magnitude of the field data, but the SAIC model overpredicts beyond an order of magnitude for a few UF{sub 6}-specific data points. The RTM-96 model provides overpredictions within a factor of 3 for all data points beyond 400 m from the source. For one data set, however, the RTM-96 model severely underpredicts the observations within 200 m of the source. Outputs of the models are most sensitive to the meteorological parameters at large distances from the source and to certain source-specific and meteorological parameters at distances close to the source. Specific recommendations are being made to improve the applicability and usefulness of the three models and to choose a specific model to support the intended analyses. Guidance is also provided on the choice of input parameters for initial dilution, building wake effects, and distance to completion of UF{sub 6} reaction with water.

Nair, S.K.; Chambers, D.B.; Park, S.H.; Radonjic, Z.R.; Coutts, P.T.; Lewis, C.J.; Hammonds, J.S.; Hoffman, F.O. [Senes Oak Ridge, Inc., TN (United States). Center for Risk Analysis

1997-11-01T23:59:59.000Z

299

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

300

A continuum model with a percolation threshold and tunneling-assisted interfacial conductivity for carbon nanotube-based nanocomposites  

SciTech Connect (OSTI)

A continuum model that possesses several desirable features of the electrical conduction process in carbon-nanotube (CNT) based nanocomposites is developed. Three basic elements are included: (i) percolation threshold, (ii) interface effects, and (iii) tunneling-assisted interfacial conductivity. We approach the first one through the selection of an effective medium theory. We approach the second one by the introduction of a diminishing layer of interface with an interfacial conductivity to build a 'thinly coated' CNT. The third one is introduced through the observation that interface conductivity can be enhanced by electron tunneling which in turn can be facilitated with the formation of CNT networks. We treat this last issue in a continuum fashion by taking the network formation as a statistical process that can be represented by Cauchy's probability density function. The outcome is a simple and yet widely useful model that can simultaneously capture all these fundamental characteristics. It is demonstrated that, without considering the interface effect, the predicted conductivity would be too high, and that, without accounting for the additional contribution from the tunneling-assisted interfacial conductivity, the predicted conductivity beyond the percolation threshold would be too low. It is with the consideration of all three elements that the theory can fully account for the experimentally measured data. We further use the developed model to demonstrate that, despite the anisotropy of the intrinsic CNT conductivity, it is its axial component along the CNT direction that dominates the overall conductivity. This theory is also proved that, even with a totally insulating matrix, it is still capable of delivering non-zero conductivity beyond the percolation threshold.

Wang, Yang; Weng, George J., E-mail: weng@jove.rutgers.edu [Department of Mechanical and Aerospace Engineering, Rutgers University, New Brunswick, New Jersey 08903 (United States); Meguid, Shaker A. [Department of Mechanical and Industrial Engineering, University of Toronto, Toronto, Ontario M5S 3G8 (Canada); Hamouda, Abdel Magid [Department of Mechanical and Industrial Engineering, Qatar University, Doha (Qatar)

2014-05-21T23:59:59.000Z

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 Retrofit Savings Using a Calibrated Building Energy Simulation Model  

E-Print Network [OSTI]

This paper presents the development of a methodology to determine retrofit energy savings in buildings when few measured preretrofit data are available. Calibration of the DOE-2 building energy analysis computer program for a 250,000 ft2 building...

Reddy, S. N.; Hunn, B. D.; Hood, D. B.

1994-01-01T23:59:59.000Z

302

Determination of fluid viscosities from biconical annular geometries: Experimental and modeling studies  

E-Print Network [OSTI]

Knowledge of viscosity of flow streams is essential for the design and operation of production facilities, drilling operations and reservoir engineering calculations. The determination of the viscosity of a reservoir fluid at downhole conditions...

Rondon, Nolys Javier

2009-05-15T23:59:59.000Z

303

Where do fossil fuel carbon dioxide emissions from California go? An analysis based on radiocarbon observations and an atmospheric transport model  

E-Print Network [OSTI]

do fossil fuel carbon dioxide emissions from California go?do fossil fuel carbon dioxide emissions from California go?1 distribution of carbon dioxide emissions from fossil fuel

2008-01-01T23:59:59.000Z

304

CARBON NANOTUBE TRANSISTORS: AN EVALUATION  

E-Print Network [OSTI]

CARBON NANOTUBE TRANSISTORS: AN EVALUATION L.C. Castro, D.L. John, and D.L. Pulfrey Department A simple, non-equilibrium model is used to evaluate the likely DC performance of carbon nanotube field and transcon- ductance close to the low-quantum-capacitance limit. Keywords: Carbon nanotubes, field

Pulfrey, David L.

305

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

306

Carbon Smackdown: Carbon Capture  

SciTech Connect (OSTI)

In this July 9, 2010 Berkeley Lab summer lecture, Lab scientists Jeff Long of the Materials Sciences and Nancy Brown of the Environmental Energy Technologies Division discuss their efforts to fight climate change by capturing carbon from the flue gas of power plants, as well as directly from the air

Jeffrey Long

2010-07-12T23:59:59.000Z

307

Carbon Smackdown: Carbon Capture  

ScienceCinema (OSTI)

In this July 9, 2010 Berkeley Lab summer lecture, Lab scientists Jeff Long of the Materials Sciences and Nancy Brown of the Environmental Energy Technologies Division discuss their efforts to fight climate change by capturing carbon from the flue gas of power plants, as well as directly from the air

Jeffrey Long

2010-09-01T23:59:59.000Z

308

Development of carbon-carbon composites from solvent extracted pitch  

SciTech Connect (OSTI)

There are several methods used to fabricate carbon-carbon composites. One used extensively in the fabrication of aerospace components such as rocket nozzles and reentry vehicle nosetips, as well as commercial components for furnace fixturing and glass manufacturing, is the densification of a woven preform with molten pitch, and the subsequent conversion of the pitch to graphite through heat treatment. Two types of pitch are used in this process; coal tar pitch and petroleum pitch. The objective of this program was to determine if a pitch produced by the direct extraction of coal could be used as a substitute for these pitches in the fabrication of carbon-carbon composites. The program involved comparing solvent extracted pitch with currently accepted pitches and rigidizing a carbon-carbon preform with solvent extracted pitch for comparison with carbon-carbon fabricated with currently available pitch.

NONE

1996-06-24T23:59:59.000Z

309

Greenhouse Gas Mitigation Options in ISEEM Global Energy Model: 2010-2050 Scenario Analysis for Least-Cost Carbon Reduction in Iron and Steel Sector  

SciTech Connect (OSTI)

The goal of the modeling work carried out in this project was to quantify long-term scenarios for the future emission reduction potentials in the iron and steel sector. The main focus of the project is to examine the impacts of carbon reduction options in the U.S. iron and steel sector under a set of selected scenarios. In order to advance the understanding of carbon emission reduction potential on the national and global scales, and to evaluate the regional impacts of potential U.S. mitigation strategies (e.g., commodity and carbon trading), we also included and examined the carbon reduction scenarios in Chinas and Indias iron and steel sectors in this project. For this purpose, a new bottom-up energy modeling framework, the Industrial Sector Energy Efficiency Modeling (ISEEM), (Karali et al. 2012) was used to provide detailed annual projections starting from 2010 through 2050. We used the ISEEM modeling framework to carry out detailed analysis, on a country-by-country basis, for the U.S., Chinas, and Indias iron and steel sectors. The ISEEM model applicable to iron and steel section, called ISEEM-IS, is developed to estimate and evaluate carbon emissions scenarios under several alternative mitigation options - including policies (e.g., carbon caps), commodity trading, and carbon trading. The projections will help us to better understand emission reduction potentials with technological and economic implications. The database for input of ISEEM-IS model consists of data and information compiled from various resources such as World Steel Association (WSA), the U.S. Geological Survey (USGS), China Steel Year Books, India Bureau of Mines (IBM), Energy Information Administration (EIA), and recent LBNL studies on bottom-up techno-economic analysis of energy efficiency measures in the iron and steel sector of the U.S., China, and India, including long-term steel production in China. In the ISEEM-IS model, production technology and manufacturing details are represented, in addition to the extensive data compiled from recent studies on bottom-up representation of efficiency measures for the sector. We also defined various mitigation scenarios including long-term production trends to project country-specific production, energy use, trading, carbon emissions, and costs of mitigation. Such analyses can provide useful information to assist policy-makers when considering and shaping future emissions mitigation strategies and policies. The technical objective is to analyze the costs of production and CO{sub 2} emission reduction in the U.S, China, and Indias iron and steel sectors under different emission reduction scenarios, using the ISEEM-IS as a cost optimization model. The scenarios included in this project correspond to various CO{sub 2} emission reduction targets for the iron and steel sector under different strategies such as simple CO{sub 2} emission caps (e.g., specific reduction goals), emission reduction via commodity trading, and emission reduction via carbon trading.

Karali, Nihan; Xu, Tengfang; Sathaye, Jayant

2013-12-01T23:59:59.000Z

310

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

SciTech Connect (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

311

PHYSICAL REVIEW B 86, 165414 (2012) Acoustic energy dissipation and thermalization in carbon nanotubes: Atomistic modeling and  

E-Print Network [OSTI]

PHYSICAL REVIEW B 86, 165414 (2012) Acoustic energy dissipation and thermalization in carbon in carbon nanotubes (CNTs) is a process that plays an important role in a range of dynamic phenomena of buckling is reproduced by incorporating a hysteresis loop into the strain energy that accounts

Zhigilei, Leonid V.

312

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

SciTech Connect (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

313

The socioeconomic determinants of correlations between stock market returns as revealed by a gravity model.  

E-Print Network [OSTI]

??Economic variants of Newton's law of universal gravitation have been used to model the flow of trade between two countries as proportional to the attraction (more)

Yang, Danni

2009-01-01T23:59:59.000Z

314

CX-000586: Categorical Exclusion Determination | Department of...  

Broader source: Energy.gov (indexed) [DOE]

Determination CX-000586: Categorical Exclusion Determination 25A1455 - Carbon Dioxide Capture with Enzyme Synthetic Analogue Date: 12152009 Location(s): Connecticut Office(s):...

315

CX-003463: Categorical Exclusion Determination | Department of...  

Broader source: Energy.gov (indexed) [DOE]

Exclusion Determination CX-003463: Categorical Exclusion Determination Carbon Dioxide Capture by Sub-Ambient Membrane Operation CX(s) Applied: A9, B3.6 Date: 08232010...

316

CX-006395: Categorical Exclusion Determination | Department of...  

Broader source: Energy.gov (indexed) [DOE]

Categorical Exclusion Determination CX-006395: Categorical Exclusion Determination Corrosion Tests on Carbon Steel Exposed to Oxalic Acid and a Sludge Simulant CX(s) Applied:...

317

CX-003937: Categorical Exclusion Determination | Department of...  

Broader source: Energy.gov (indexed) [DOE]

Determination CX-003937: Categorical Exclusion Determination Hawaii Energy Sustainability Program (Subtask 2.4.1: Evaluate Carbonized Biomass Samples) CX(s) Applied: A9,...

318

CX-008294: Categorical Exclusion Determination | Department of...  

Broader source: Energy.gov (indexed) [DOE]

4: Categorical Exclusion Determination CX-008294: Categorical Exclusion Determination Waste Heat Integration with Solvent Process for More Efficient Carbon Dioxide Removal from...

319

CX-008293: Categorical Exclusion Determination | Department of...  

Broader source: Energy.gov (indexed) [DOE]

93: Categorical Exclusion Determination CX-008293: Categorical Exclusion Determination Waste Heat Integration with Solvent Process for More Efficient Carbon Dioxide Removal from...

320

CX-008295: Categorical Exclusion Determination | Department of...  

Broader source: Energy.gov (indexed) [DOE]

5: Categorical Exclusion Determination CX-008295: Categorical Exclusion Determination Waste Heat Integration with Solvent Process for More Efficient Carbon Dioxide Removal from...

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

CX-008292: Categorical Exclusion Determination | Department of...  

Broader source: Energy.gov (indexed) [DOE]

2: Categorical Exclusion Determination CX-008292: Categorical Exclusion Determination Waste Heat Integration with Solvent Process for More Efficient Carbon Dioxide Removal from...

322

CX-001161: Categorical Exclusion Determination | Department of...  

Broader source: Energy.gov (indexed) [DOE]

Determination CX-001161: Categorical Exclusion Determination An Evaluation of the Carbon Sequestration Potential of the Cambro-Ordovician Strata of the Illinois and...

323

CX-001163: Categorical Exclusion Determination | Department of...  

Broader source: Energy.gov (indexed) [DOE]

Determination CX-001163: Categorical Exclusion Determination An Evaluation of the Carbon Sequestration Potential of the Cambro-Ordovician Strata of the Illinois and...

324

CX-007111: Categorical Exclusion Determination | Department of...  

Broader source: Energy.gov (indexed) [DOE]

Exclusion Determination CX-007111: Categorical Exclusion Determination Shallow Carbon Sequestration Demonstration Project (Iatan Generating Station) CX(s) Applied: B3.1...

325

CX-011434: Categorical Exclusion Determination | Department of...  

Broader source: Energy.gov (indexed) [DOE]

Exclusion Determination CX-011434: Categorical Exclusion Determination Midwest Regional Carbon Sequestration Partnership - Phase III (Categorical Exclusion (CX)-A Tasks) CX(s)...

326

CX-009326: Categorical Exclusion Determination | Department of...  

Broader source: Energy.gov (indexed) [DOE]

Exclusion Determination CX-009326: Categorical Exclusion Determination Midwest Regional Carbon Sequestration Partnership - Subtask 1.7 CX(s) Applied: B3.1 Date: 09282012...

327

CX-007118: Categorical Exclusion Determination | Department of...  

Broader source: Energy.gov (indexed) [DOE]

Exclusion Determination CX-007118: Categorical Exclusion Determination Shallow Carbon Sequestration Demonstration Project CX(s) Applied: B3.1 Date: 10042011...

328

CX-001159: Categorical Exclusion Determination | Department of...  

Broader source: Energy.gov (indexed) [DOE]

Determination CX-001159: Categorical Exclusion Determination An Evaluation of the Carbon Sequestration Potential of the Cambro-Ordovician Strata of the Illinois and...

329

CX-012261: Categorical Exclusion Determination | Department of...  

Broader source: Energy.gov (indexed) [DOE]

Determination CX-012261: Categorical Exclusion Determination An Evaluation of the Carbon Sequestration Potential of the Cambro-Ordovician Strata of the Illinois CX(s)...

330

CX-008507: Categorical Exclusion Determination | Department of...  

Broader source: Energy.gov (indexed) [DOE]

Exclusion Determination CX-008507: Categorical Exclusion Determination Midwest Regional Carbon Sequestration Partnership - Phase Three CX(s) Applied: B3.1, B5.3 Date: 07162012...

331

CX-003877: Categorical Exclusion Determination | Department of...  

Broader source: Energy.gov (indexed) [DOE]

Determination CX-003877: Categorical Exclusion Determination Hybrid MembraneAbsorption Process for Post-Combustion Carbon Dioxide Capture CX(s) Applied: B3.6 Date: 0910...

332

CX-010910: Categorical Exclusion Determination | Department of...  

Broader source: Energy.gov (indexed) [DOE]

Determination CX-010910: Categorical Exclusion Determination Hybrid Membrane-Absorption Carbon Dioxide (CO2) Capture Process CX(s) Applied: B3.6 Date: 09252013...

333

CX-003876: Categorical Exclusion Determination | Department of...  

Broader source: Energy.gov (indexed) [DOE]

Determination CX-003876: Categorical Exclusion Determination Hybrid MembraneAbsorption Process for Post-Combustion Carbon Dioxide Capture CX(s) Applied: B3.6 Date: 0910...

334

CX-004394: Categorical Exclusion Determination | Department of...  

Broader source: Energy.gov (indexed) [DOE]

Determination CX-004394: Categorical Exclusion Determination Hybrid MembraneAbsorption Process for Post-Combustion Carbon Dioxide Capture CX(s) Applied: B3.6 Date: 1105...

335

CX-010911: Categorical Exclusion Determination | Department of...  

Broader source: Energy.gov (indexed) [DOE]

Determination CX-010911: Categorical Exclusion Determination Hybrid Membrane-Absorption Carbon Dioxide (CO2) Capture Process CX(s) Applied: B3.6 Date: 09252013...

336

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 (OSTI)

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

337

Industrial Carbon Management Initiative (ICMI)  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

heat in a combustion process while producing a concentrated CO 2 stream to facilitate carbon capture. Chemical looping research efforts can be categorized as: modeling tool...

338

Multi-scale geospatial agroecosystem modeling: a case study on the influence of soil data resolution on carbon budget estimates  

SciTech Connect (OSTI)

The development of effective measures to stabilize atmospheric CO2 concentration and mitigate negative impacts of climate change requires accurate quantification of the spatial variation and magnitude of the terrestrial carbon (C) flux. However, the spatial pattern and strength of terrestrial C sinks and sources remain uncertain. In this study, we designed a spatially-explicit agroecosystem modeling system by integrating the Environmental Policy Integrated Climate (EPIC) model with multiple sources of geospatial and surveyed datasets (including crop type map, elevation, climate forcing, fertilizer application, tillage type and distribution, and crop planting and harvesting date), and applied it to examine the sensitivity of cropland C flux simulations to two widely used soil databases (i.e. State Soil Geographic-STATSGO of a scale of 1:250,000 and Soil Survey Geographic-SSURGO of a scale of 1:24,000) in Iowa, USA. To efficiently execute numerous EPIC runs resulting from the use of high resolution spatial data (56m), we developed a parallelized version of EPIC. Both STATSGO and SSURGO led to similar simulations of crop yields and Net Ecosystem Production (NEP) estimates at the State level. However, substantial differences were observed at the county and sub-county (grid) levels. In general, the fine resolution SSURGO data outperformed the coarse resolution STATSGO data for county-scale crop-yield simulation, and within STATSGO, the area-weighted approach provided more accurate results. Further analysis showed that spatial distribution and magnitude of simulated NEP were more sensitive to the resolution difference between SSURGO and STATSGO at the county or grid scale. For over 60% of the cropland areas in Iowa, the deviations between STATSGO- and SSURGO-derived NEP were larger than 1MgCha(-1)yr(-1), or about half of the average cropland NEP, highlighting the significant uncertainty in spatial distribution and magnitude of simulated C fluxes resulting from differences in soil data resolution.

Zhang, Xuesong; Sahajpal, Ritvik; Manowitz, D.; Zhao, Kaiguang; LeDuc, Stephen D.; Xu, Min; Xiong, Wei; Zhang, Aiping; Izaurralde, Roberto C.; Thomson, Allison M.; West, Tristram O.; Post, W. M.

2014-05-01T23:59:59.000Z

339

Carbon Capture and Storage, 2008  

SciTech Connect (OSTI)

The U.S. Department of Energy is researching the safe implementation of a technology called carbon sequestration, also known as carbon capture and storage, or CCS. Based on an oilfield practice, this approach stores carbon dioxide, or CO2 generated from human activities for millennia as a means to mitigate global climate change. In 2003, the Department of Energys National Energy Technology Laboratory formed seven Regional Carbon Sequestration Partnerships to assess geologic formations suitable for storage and to determine the best approaches to implement carbon sequestration in each region. This video describes the work of these partnerships.

2009-03-19T23:59:59.000Z

340

Carbon Capture and Storage, 2008  

ScienceCinema (OSTI)

The U.S. Department of Energy is researching the safe implementation of a technology called carbon sequestration, also known as carbon capture and storage, or CCS. Based on an oilfield practice, this approach stores carbon dioxide, or CO2 generated from human activities for millennia as a means to mitigate global climate change. In 2003, the Department of Energys National Energy Technology Laboratory formed seven Regional Carbon Sequestration Partnerships to assess geologic formations suitable for storage and to determine the best approaches to implement carbon sequestration in each region. This video describes the work of these partnerships.

None

2010-01-08T23:59:59.000Z

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

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

342

Ab-initio coupled-cluster effective interactions for the shell model: Application to neutron-rich oxygen and carbon isotopes  

E-Print Network [OSTI]

We derive and compute effective valence-space shell-model interactions from ab-initio coupled-cluster theory and apply them to open-shell and neutron-rich oxygen and carbon isotopes. Our shell-model interactions are based on nucleon-nucleon and three-nucleon forces from chiral effective-field theory. We compute the energies of ground and low-lying states, and find good agreement with experiment. In particular our calculations are consistent with the N=14, 16 shell closures in oxygen-22 and oxygen-24, while for carbon-20 the corresponding N=14 closure is weaker. We find good agreement between our coupled-cluster effective-interaction results with those obtained from standard single-reference coupled-cluster calculations for up to eight valence neutrons.

G. R. Jansen; J. Engel; G. Hagen; P. Navratil; A. Signoracci

2014-02-11T23:59:59.000Z

343

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

344

Numerical model to determine the composition of H2ONaClCaCl2 fluid inclusions based on  

E-Print Network [OSTI]

Numerical model to determine the composition of H2O­NaCl­CaCl2 fluid inclusions based 2010 Abstract Natural fluids approximated by the H2O­NaCl­CaCl2 system are common in a wide range the compositions of fluid inclusions in the H2O­NaCl­CaCl2 sys- tem based on microthermometric and microanalytical

Bodnar, Robert J.

345

Technosocial Modeling for Determining the Status and Nature of a States Nuclear Activities  

SciTech Connect (OSTI)

The International Atomic Energy Agency State Evaluation Process: The Role of Information Analysis in Reaching Safeguards Conclusions (Mathews et al. 2008), several examples of nonproliferation models using analytical software were developed that may assist the IAEA with collecting, visualizing, analyzing, and reporting information in support of the State Evaluation Process. This paper focuses on one of the examples a set of models developed in the Proactive Scenario Production, Evidence Collection, and Testing (ProSPECT) software that evaluates the status and nature of a states nuclear activities. The models use three distinct subject areas to perform this assessment: the presence of nuclear activities, the consistency of those nuclear activities with national nuclear energy goals, and the geopolitical context in which those nuclear activities are taking place. As a proof-of-concept for the models, a crude case study was performed. The study, which attempted to evaluate the nuclear activities taking place in Syria prior to September 2007, yielded illustrative, yet inconclusive, results. Due to the inconclusive nature of the case study results, changes that may improve the models efficiency and accuracy are proposed.

Gastelum, Zoe N.; Harvey, Julia B.

2009-09-25T23:59:59.000Z

346

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

SciTech Connect (OSTI)

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

347

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

SciTech Connect (OSTI)

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

348

9, 1443714473, 2012 Soil carbon drivers  

E-Print Network [OSTI]

BGD 9, 14437­14473, 2012 Soil carbon drivers and benchmarks in Earth system models K. E. O. Todd if available. Causes of variation in soil carbon predictions from CMIP5 Earth system models and comparison #12;BGD 9, 14437­14473, 2012 Soil carbon drivers and benchmarks in Earth system models K. E. O. Todd

Ickert-Bond, Steffi

349

Atmospheric three-dimensional inverse modeling of regional industrial emissions and global oceanic uptake of carbon tetrachloride  

E-Print Network [OSTI]

Carbon tetrachloride (CCl4) has substantial stratospheric ozone depletion potential and its consumption is controlled under the Montreal Protocol and its amendments. We implement a Kalman filter using atmospheric CCl4 ...

Xiao, X.

350

Assessment of carbon sequestration and timber production of Scots pine across Scotland using the process-based model 3-PGN  

E-Print Network [OSTI]

detailed eco-physiological interpretation of the environmental factors affecting Scots pine growth and it provided an assessment of carbon sequestration under the scenario of sustainable, normal production and its effects from the environment. Finally...

Xenakis, Georgios

2007-11-27T23:59:59.000Z

351

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.

352

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

353

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

SciTech Connect (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

354

Model independent determination of the light-cone wave functions for exclusive processes  

E-Print Network [OSTI]

We present a method to compute, by numerical simulations of lattice QCD, the light-cone wave functions which enter exclusive processes at large momentum transfer, such as electromagnetic elastic scatterings, or exclusive semi-leptonic decays as B -> pi (B -> rho) and radiative decays as B -> K* gamma. The method is based on first principles and does not require any model assumption.

Aglietti, U; Corb, G; Franco, E; Martinelli, G; Silvestrini, L

1998-01-01T23:59:59.000Z

355

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

SciTech Connect (OSTI)

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

356

Reservoir Characterization, Formation Evaluation, and 3D Geologic Modeling of the Upper Jurassic Smackover Microbial Carbonate Reservoir and Associated Reservoir Facies at Little Cedar Creek Field, Northeastern Gulf of Mexico  

E-Print Network [OSTI]

characterization, formation evaluation, and 3D geologic modeling provides a sound framework in the establishment of a field/reservoir-wide development plan for optimal primary and enhanced recovery for these Upper Jurassic microbial carbonate and associated...

Al Haddad, Sharbel

2012-10-19T23:59:59.000Z

357

Transport parameter determination and modeling of sodium and strontium plumes at the Idaho National Engineering Laboratory  

E-Print Network [OSTI]

finite-element method to model a case of chromium contamination with some success. Bobcrtson, '1974~ used au iterative, alternating- direction. inrplicit finite-difference scheme to solve the groundwater flow equation and a. nrodified method... the location of the INEL and generalized groundwater flow lines of the Snake River Plain aquifer [from Barraclough et al. , 1981). . 12 3. Map showing the major facilities and surface water features at the INEL [from Robertson et al. , 1974]. 4. Volcanic...

Londergan, John Thomas

1987-01-01T23:59:59.000Z

358

Quantification and utilization of subjectively determined data in the construction of mathematical models  

E-Print Network [OSTI]

on Justification of the Use of Expertise Previous Uses of Expertise in Fore- casting The DELPHI Method PATTERN Improvement of Existing Methods. A NEW METHOD . Introduction Collection of Data. Analysis of Data and Decision Conclusion. 1 I 2 3 4 6 7... III. A SAMPLE PROBLEM 54 REFERENCES 85 CHAPTER I THE STATE OF THE ART Introduction The building of models designed to assist in the description of future events has often encountered a very serious limitation. This is due to the methods...

Haynes, Grady Lee

1966-01-01T23:59:59.000Z

359

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

SciTech Connect (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 850C 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

360

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

SciTech Connect (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 850C 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

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

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

SciTech Connect (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

362

Modeling LIDAR Detection of Biological Aerosols to Determine Optimum Implementation Strategy  

SciTech Connect (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

363

Determining SUSY model parameters and masses at the LHC using cross-sections, kinematic edges and other observables.  

E-Print Network [OSTI]

ar X iv :h ep -p h/ 05 08 14 3v 2 3 0 A ug 2 00 5 Preprint typeset in JHEP style - HYPER VERSION CAV-HEP-2005-15 ATL-PHYS-PUB-2005-013 ATL-COM-PHYS-2005-033 Determining SUSY model parameters and masses at the LHC using cross-sections, kinematic... with the endpoint mea- surements. Note that p(m|eobs) is the equivalent of the P ?(x) defined later on in equation (A.2), as it is defined only up to an unknown normalisation constant. So, in order to plot the probability distribution, one follows the following...

Lester, Christopher G; Parker, Michael A; White, Martin J

364

Numerical determination of OPE coefficients in the 3D Ising model from off-critical correlators  

E-Print Network [OSTI]

We propose a general method for the numerical evaluation of OPE coefficients in three dimensional Conformal Field Theories based on the study of the conformal perturbation of two point functions in the vicinity of the critical point. We test our proposal in the three dimensional Ising Model, looking at the magnetic perturbation of the $$, $$ and $$ correlators from which we extract the values of $C^{\\sigma}_{\\sigma\\epsilon}=1.07(3)$ and $C^{\\epsilon}_{\\epsilon\\epsilon}=1.45(30)$. Our estimate for $C^{\\sigma}_{\\sigma\\epsilon}$ agrees with those recently obtained using conformal bootstrap methods, while $C^{\\epsilon}_{\\epsilon\\epsilon}$, as far as we know, is new and could be used to further constrain conformal bootstrap analyses of the 3d Ising universality class.

Caselle, M; Magnoli, N

2015-01-01T23:59:59.000Z

365

Determining Plutonium Mass in Spent Fuel with Nondestructive Assay Techniques -- Preliminary Modeling Results Emphasizing Integration among Techniques  

SciTech Connect (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

366

Radiological Modeling for Determination of Derived Concentration Levels of an Area with Uranium Residual Material - 13533  

SciTech Connect (OSTI)

As a result of a pilot project developed at the old Spanish 'Junta de Energia Nuclear' to extract uranium from ores, tailings materials were generated. Most of these residual materials were sent back to different uranium mines, but a small amount of it was mixed with conventional building materials and deposited near the old plant until the surrounding ground was flattened. The affected land is included in an area under institutional control and used as recreational area. At the time of processing, uranium isotopes were separated but other radionuclides of the uranium decay series as Th-230, Ra-226 and daughters remain in the residue. Recently, the analyses of samples taken at different ground's depths confirmed their presence. This paper presents the methodology used to calculate the derived concentration level to ensure that the reference dose level of 0.1 mSv y-1 used as radiological criteria. In this study, a radiological impact assessment was performed modeling the area as recreational scenario. The modelization study was carried out with the code RESRAD considering as exposure pathways, external irradiation, inadvertent ingestion of soil, inhalation of resuspended particles, and inhalation of radon (Rn-222). As result was concluded that, if the concentration of Ra-226 in the first 15 cm of soil is lower than, 0.34 Bq g{sup -1}, the dose would not exceed the reference dose. Applying this value as a derived concentration level and comparing with the results of measurements on the ground, some areas with a concentration of activity slightly higher than latter were found. In these zones the remediation proposal has been to cover with a layer of 15 cm of clean material. This action represents a reduction of 85% of the dose and ensures compliance with the reference dose. (authors)

Perez-Sanchez, Danyl [CIEMAT, Avenida Complutense 40, 28040, Madrid (Spain)] [CIEMAT, Avenida Complutense 40, 28040, Madrid (Spain)

2013-07-01T23:59:59.000Z

367

Coupled Flow and Deformation Modeling of Carbon Dioxide Migration in the Presence of a Caprock Fracture during Injection  

SciTech Connect (OSTI)

Understanding the transport of carbon dioxide (CO{sub 2}) during long-term CO{sub 2} injection into a typical geologic reservoir, such as a saline aquifer, could be complicated because of changes in geochemical, hydrogeological, and hydromechanical behavior. While the caprock layer overlying the target aquifer is intended to provide a tight, impermeable seal in securing injected CO{sub 2}, the presence of geologic uncertainties, such as a caprock fracture or fault, may provide a channel for CO{sub 2} leakage. There could also be a possibility of the activation of a new or existing dormant fault or fracture, which could act as a leakage pathway. Such a leakage event during CO{sub 2} injection may lead to a different pressure and ground response over a period of time. In the present study, multiphase fluid flow simulations in porous media coupled with geomechanics were used to investigate the overburden geologic response and plume behavior during CO{sub 2} injection in the presence of a hypothetical permeable fractured zone in a caprock, existing or activated. Both single-phase and multiphase fluid flow simulations were performed. The CO{sub 2} migration through an existing fractured zone leads to changes in the fluid pressure in the overburden geologic layers and could have a significant impact on ground deformation behavior. Results of the study show that pressure signatures and displacement patterns are significantly different in the presence of a fractured zone in the caprock layer. The variation in pressure and displacement signatures because of the presence of a fractured zone in the caprock at different locations may be useful in identifying the presence of a fault/fractured zone in the caprock. The pressure signatures can also serve as a mechanism to identify the activation of leakage pathways through the caprock during CO{sub 2} injection. Pressure response and ground deformation behavior from sequestration modeling could be useful in the development of smart technologies to monitor safe CO{sub 2} storage and understand CO{sub 2} transport, with limited field instrumentation.

Siriwardane, Hema J.; Gondle, Raj K.; Bromhal, Grant S.

2013-08-01T23:59:59.000Z

368

Causes of variation in soil carbon simulations from CMIP5 Earth system models and comparison with observations  

E-Print Network [OSTI]

and benchmarks in Earth system models sitivity of the Amazonand benchmarks in Earth system models Thornton, P. E. ,simulations from CMIP5 Earth system models and comparison

2013-01-01T23:59:59.000Z

369

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

SciTech Connect (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

370

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

Broader source: Energy.gov (indexed) [DOE]

Exclusion Determination Development of Novel Carbon Sorbents for Carbon Dioxide Capture CX(s) Applied: B3.6 Date: 01302013 Location(s): Alabama Offices(s): National Energy...

371

Enhanced terrestrial carbon uptake in the Northern High Latitudes in the 21st century from the Coupled Carbon  

E-Print Network [OSTI]

the Coupled Carbon Cycle Climate Model Intercomparison Project model projections H A I F E N G Q I A N *, R E Carbon Cycle Climate Model Intercomparison Project. Our analysis suggests that the NHL will be a carbon the intense warming there enhances SOM decomposition, soil organic carbon (SOC) storage continues to increase

Zeng, Ning

372

REGIONAL IMPACTS OF THE GLOBAL CARBON STAKES: LONG-TERM PROSPECTIVE WITH THE TIMES INTEGRATED ASSESSMENT MODEL  

E-Print Network [OSTI]

, the progress of primary energy consumption and the energy mix. This paper compares global efforts on CO2 and Nadia Maïzi 33rd IAEE International Conference: "The future of energy: global challenges, diverse the carbon constraints. JEL O21, Q29, Q4, Q54, Q58 Keywords Global energy system, CO2 mitigation targets

Paris-Sud XI, Université de

373

INTEGRATED GEOLOGIC-ENGINEERING MODEL FOR REEF AND CARBONATE SHOAL RESERVOIRS ASSOCIATED WITH PALEOHIGHS: UPPER JURASSIC SMACKOVER FORMATION, NORTHEASTERN GULF OF MEXICO  

SciTech Connect (OSTI)

The University of Alabama, in cooperation with Texas A&M University, McGill University, Longleaf Energy Group, Strago Petroleum Corporation, and Paramount Petroleum Company, has undertaken an integrated, interdisciplinary geoscientific and engineering research project. The project is designed to characterize and model reservoir architecture, pore systems and rock-fluid interactions at the pore to field scale in Upper Jurassic Smackover reef and carbonate shoal reservoirs associated with varying degrees of relief on pre-Mesozoic basement paleohighs in the northeastern Gulf of Mexico. The project effort includes the prediction of fluid flow in carbonate reservoirs through reservoir simulation modeling which utilizes geologic reservoir characterization and modeling and the prediction of carbonate reservoir architecture, heterogeneity and quality through seismic imaging. The primary goal of the project is to increase the profitability, producibility and efficiency of recovery of oil from existing and undiscovered Upper Jurassic fields characterized by reef and carbonate shoals associated with pre-Mesozoic basement paleohighs. Geoscientific reservoir property, geophysical seismic attribute, petrophysical property, and engineering property characterization has shown that reef (thrombolite) and shoal reservoir lithofacies developed on the flanks of high-relief crystalline basement paleohighs (Vocation Field example) and on the crest and flanks of low-relief crystalline basement paleohighs (Appleton Field example). The reef thrombolite lithofacies have higher reservoir quality than the shoal lithofacies due to overall higher permeabilities and greater interconnectivity. Thrombolite dolostone flow units, which are dominated by dolomite intercrystalline and vuggy pores, are characterized by a pore system comprised of a higher percentage of large-sized pores and larger pore throats. Rock-fluid interactions (diagenesis) studies have shown that although the primary control on reservoir architecture and geographic distribution of Smackover reservoirs is the fabric and texture of the depositional lithofacies, diagenesis (chiefly dolomitization) is a significant factor that preserves and enhances reservoir quality. The evaporative pumping mechanism is favored to explain the dolomitization of the thrombolite doloboundstone and dolostone reservoir flow units at Appleton and Vocation Fields. Geologic modeling, reservoir simulation, and the testing and applying the resulting integrated geologic-engineering models have shown that little oil remains to be recovered at Appleton Field and a significant amount of oil remains to be recovered at Vocation Field through a strategic infill drilling program. The drive mechanisms for primary production in Appleton and Vocation Fields remain effective; therefore, the initiation of a pressure maintenance program or enhanced recovery project is not required at this time. The integrated geologic-engineering model developed for a low-relief paleohigh (Appleton Field) was tested for three scenarios involving the variables of present-day structural elevation and the presence/absence of potential reef thrombolite lithofacies. In each case, the predictions based upon the model were correct. From this modeling, the characteristics of the ideal prospect in the basement ridge play include a low-relief paleohigh associated with dendroidal/chaotic thrombolite doloboundstone and dolostone that has sufficient present-day structural relief so that these carbonates rest above the oil-water contact. Such a prospect was identified from the modeling, and it is located northwest of well Permit No. 3854B (Appleton Field) and south of well No. Permit No.11030B (Northwest Appleton Field).

Ernest A. Mancini

2004-02-25T23:59:59.000Z

374

Carbon Nanotubes.  

E-Print Network [OSTI]

?? Carbon nanotubes have extraordinary mechanical, electrical, thermal andoptical properties. They are harder than diamond yet exible, have betterelectrical conductor than copper, but can also (more)

Fredriksson, Tore

2014-01-01T23:59:59.000Z

375

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 footprint for their processing facility and products. The importance of establishing a carbon footprint

Balasundaram, Balabhaskar "Baski"

376

A conceptual model of the roles of price, quality, and intermediary constructs in determining behavioral intention to visit a festival  

E-Print Network [OSTI]

Model 1???????.... 96 The Second Revised Structural Model 1??????? 99 The Final Revised Structural Model 1???????... 102 Initial Structural Model 2????????????... 106 The Revised Structural Model 2??????????. 109... The Initial Structural Model 2?...???????????... 105 FIGURE 12 The Revised Structural Model 2????????????... 108 FIGURE 13 Final Structural Model and Standardized Parameter Estimates of Model 1??????????????.?????.?.. 115 FIGURE 14 Final...

Lee, So Yon

2006-08-16T23:59:59.000Z

377

The CPA Equation of State and an Activity Coefficient Model for Accurate Molar Enthalpy Calculations of Mixtures with Carbon Dioxide and Water/Brine  

E-Print Network [OSTI]

Thermodynamic property calculations of mixtures containing carbon dioxide (CO$_2$) and water, including brines, are essential in theoretical models of many natural and industrial processes. The properties of greatest practical interest are density, solubility, and enthalpy. Many models for density and solubility calculations have been presented in the literature, but there exists only one study, by Spycher and Pruess, that has compared theoretical molar enthalpy predictions with experimental data. In this report, we recommend two different models for enthalpy calculations: the CPA equation of state by Li and Firoozabadi, and the CO$_2$ activity coefficient model by Duan and Sun. We show that the CPA equation of state, which has been demonstrated to provide good agreement with density and solubility data, also accurately calculates molar enthalpies of pure CO$_2$, pure water, and both CO$_2$-rich and aqueous (H$_2$O-rich) mixtures of the two species. It is applicable to a wider range of conditions than the Spycher and Pruess model. In aqueous sodium chloride (NaCl) mixtures, we show that Duan and Sun's model yields accurate results for the partial molar enthalpy of CO$_2$. It can be combined with another model for the brine enthalpy to calculate the molar enthalpy of H$_2$O-CO$_2$-NaCl mixtures. We conclude by explaining how the CPA equation of state may be modified to further improve agreement with experiments. This generalized CPA is the basis of our future work on this topic.

P. C. Myint; Y. Hao; A. Firoozabadi

2015-04-20T23:59:59.000Z

378

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

379

Total Organic Carbon Analyzer | EMSL  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Total Organic Carbon Analyzer Total Organic Carbon Analyzer The carbon analyzer is used to analyze total carbon (TC), inorganic carbon (IC), total organic carbon (TOC), purgeable...

380

Carbonation Mechanism of Reservoir Rock by Supercritical Carbon Dioxide  

Broader source: Energy.gov [DOE]

Project Objectives: Elucidate comprehensively the carbonation reaction mechanisms between supercritical carbon dioxide (scCO2) and reservoir rocks consisting of different mineralogical compositions in aqueous and non-aqueous environments at temperatures of up to 250C, and to develop chemical modeling of CO2-reservior rock interactions.

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

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 (OSTI)

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

382

SCENARIOS FOR DEEP CARBON EMISSION REDUCTIONS FROM ELECTRICITY BY 2050 IN WESTERN NORTH AMERICA USING THE SWITCH ELECTRIC POWER SECTOR PLANNING MODEL California's Carbon Challenge Phase II Volume II  

SciTech Connect (OSTI)

This study used a state-of-the-art planning model called SWITCH for the electric power system to investigate the evolution of the power systems of California and western North America from present-day to 2050 in the context of deep decarbonization of the economy. Researchers concluded that drastic power system carbon emission reductions were feasible by 2050 under a wide range of possible futures. The average cost of power in 2050 would range between $149 to $232 per megawatt hour across scenarios, a 21 to 88 percent increase relative to a business-as-usual scenario, and a 38 to 115 percent increase relative to the present-day cost of power. The power system would need to undergo sweeping change to rapidly decarbonize. Between present-day and 2030 the evolution of the Western Electricity Coordinating Council power system was dominated by implementing aggressive energy efficiency measures, installing renewable energy and gas-fired generation facilities and retiring coal-fired generation. Deploying wind, solar and geothermal power in the 2040 timeframe reduced power system emissions by displacing gas-fired generation. This trend continued for wind and solar in the 2050 timeframe but was accompanied by large amounts of new storage and long-distance high-voltage transmission capacity. Electricity storage was used primarily to move solar energy from the daytime into the night to charge electric vehicles and meet demand from electrified heating. Transmission capacity over the California border increased by 40 - 220 percent by 2050, implying that transmission siting, permitting, and regional cooperation will become increasingly important. California remained a net electricity importer in all scenarios investigated. Wind and solar power were key elements in power system decarbonization in 2050 if no new nuclear capacity was built. The amount of installed gas capacity remained relatively constant between present-day and 2050, although carbon capture and sequestration was installed on some gas plants by 2050.

Collaboration/ University of California, Berkeley; Nelson, James; Mileva, Ana; Johnston, Josiah; Kammen, Daniel; Wei, Max; Greenblatt, Jeffrey

2014-01-01T23:59:59.000Z

383

Use of ARM observations and numerical models to determine radiative and latent heating profiles of mesoscale convective systems for general circulation models  

SciTech Connect (OSTI)

We examined cloud radar data in monsoon climates, using cloud radars at Darwin in the Australian monsoon, on a ship in the Bay of Bengal in the South Asian monsoon, and at Niamey in the West African monsoon. We followed on with a more in-depth study of the continental MCSs over West Africa. We investigated whether the West African anvil clouds connected with squall line MCSs passing over the Niamey ARM site could be simulated in a numerical model by comparing the observed anvil clouds to anvil structures generated by the Weather Research and Forecasting (WRF) mesoscale model at high resolution using six different ice-phase microphysical schemes. We carried out further simulations with a cloud-resolving model forced by sounding network budgets over the Niamey region and over the northern Australian region. We have devoted some of the effort of this project to examining how well satellite data can determine the global breadth of the anvil cloud measurements obtained at the ARM ground sites. We next considered whether satellite data could be objectively analyzed to so that their large global measurement sets can be systematically related to the ARM measurements. Further differences were detailed between the land and ocean MCS anvil clouds by examining the interior structure of the anvils with the satellite-detected the CloudSat Cloud Profiling Radar (CPR). The satellite survey of anvil clouds in the Indo-Pacific region was continued to determine the role of MCSs in producing the cloud pattern associated with the MJO.

Houze, Jr., Robert A. [University of Washington Dept. of Atmospheric Sciences

2013-11-13T23:59:59.000Z

384

Selection of coals of different maturities for CO2 Storage by modelling of CH4 and CO2 adsorption isotherms  

E-Print Network [OSTI]

of this study is to compare and model pure gas sorption isotherms (CO2 and CH4) for well-characterised coals of different maturities to determine the most suitable coal for CO2 storage. Carbon dioxide and methane; Coals; Methane and carbon dioxide adsorption; Modelling isotherms 1. Introduction CO2 is a greenhouse

Paris-Sud XI, Université de

385

Climate Modeling using High-Performance Computing The Center for Applied Scientific Computing (CASC) and the LLNL Climate and Carbon  

E-Print Network [OSTI]

and NCAR in the development of a comprehensive, earth systems model. This model incorporates the most-performance climate models. Through the addition of relevant physical processes, we are developing an earth systems modeling capability as well. Our collaborators in climate research include the National Center

386

Determining Columbia and Snake River Project Tailrace and Forebay Zones of Hydraulic Influence using MASS2 Modeling  

SciTech Connect (OSTI)

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

387

Carbon nanotube IR detectors (SV)  

SciTech Connect (OSTI)

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

388

Determining the Mechanical Constitutive Properties of Metals as Function of Strain Rate and temperature: A Combined Experimental and Modeling Approach  

SciTech Connect (OSTI)

Development and validation of constitutive models for polycrystalline materials subjected to high strain-rate loading over a range of temperatures are needed to predict the response of engineering materials to in-service type conditions. To account accurately for the complex effects that can occur during extreme and variable loading conditions, requires significant and detailed computational and modeling efforts. These efforts must be integrated fully with precise and targeted experimental measurements that not only verify the predictions of the models, but also provide input about the fundamental processes responsible for the macroscopic response. Achieving this coupling between modeling and experiment is the guiding principle of this program. Specifically, this program seeks to bridge the length scale between discrete dislocation interactions with grain boundaries and continuum models for polycrystalline plasticity. Achieving this goal requires incorporating these complex dislocation-interface interactions into the well-defined behavior of single crystals. Despite the widespread study of metal plasticity, this aspect is not well understood for simple loading conditions, let alone extreme ones. Our experimental approach includes determining the high-strain rate response as a function of strain and temperature with post-mortem characterization of the microstructure, quasi-static testing of pre-deformed material, and direct observation of the dislocation behavior during reloading by using the in situ transmission electron microscope deformation technique. These experiments will provide the basis for development and validation of physically-based constitutive models. One aspect of the program involves the direct observation of specific mechanisms of micro-plasticity, as these indicate the boundary value problem that should be addressed. This focus on the pre-yield region in the quasi-static effort (the elasto-plastic transition) is also a tractable one from an experimental and modeling viewpoint. In addition, our approach will minimize the need to fit model parameters to experimental data to obtain convergence. These are critical steps to reach the primary objective of simulating and modeling material performance under extreme loading conditions. During this project, the following achievements have been obtained: 1. Twins have been observed to act as barriers to dislocation propagation and as sources of and sinks to dislocations. 2. Nucleation of deformation twins in nitrogen strengthened steel is observed to be closely associated with planar slip bands. The appearance of long twins through heavily dislocated microstructures occurs by short twins nucleating at one slip band, propagating through the dislocation-free region, and terminating at the next slip band. This process is repeated throughout the entire grain. 3. A tamped-laser ablation loading technique has been developed to introduce high strain rate, high stress and low strains. 4. Both dislocation slip and twinning are present in high strain-rate deformed zirconium, with the relative contribution of each mode to the deformation depending on the initial texture. 5. In situ IR thermal measurements have been used to show that the majority of plastic work is dissipated as heat even under conditions in which twinning is the dominant deformation mode.

Ian Robertson

2007-04-28T23:59:59.000Z

389

CX-011443: Categorical Exclusion Determination | Department of...  

Broader source: Energy.gov (indexed) [DOE]

Categorical Exclusion Determination Sorbent Based Post-Combustion Carbon Dioxide (CO2) Slipstream Testing CX(s) Applied: B3.6 Date: 11132013 Location(s): Alabama...

390

CX-011441: Categorical Exclusion Determination | Department of...  

Broader source: Energy.gov (indexed) [DOE]

Categorical Exclusion Determination Sorbent Based Post-Combustion Carbon Dioxide (CO2) Slipstream Testing CX(s) Applied: B3.6 Date: 11132013 Location(s): Colorado...

391

CX-011442: Categorical Exclusion Determination | Department of...  

Broader source: Energy.gov (indexed) [DOE]

Categorical Exclusion Determination Sorbent Based Post-Combustion Carbon Dioxide (CO2) Slipstream Testing CX(s) Applied: B3.6 Date: 11132013 Location(s): Colorado...

392

CX-011785: Categorical Exclusion Determination | Department of...  

Broader source: Energy.gov (indexed) [DOE]

CX-011785: Categorical Exclusion Determination Ion Advanced Solvent Carbon Dioxide Capture Pilot Project CX(s) Applied: A9, A11 Date: 02192014 Location(s): Colorado...

393

CX-011274: Categorical Exclusion Determination | Department of...  

Broader source: Energy.gov (indexed) [DOE]

CX-011274: Categorical Exclusion Determination Ion Advanced Solvent Carbon Dioxide Capture Pilot Project CX(s) Applied: A9, A11 Date: 09262013 Location(s): North Dakota...

394

CX-003442: Categorical Exclusion Determination | Department of...  

Broader source: Energy.gov (indexed) [DOE]

CX-003442: Categorical Exclusion Determination Post-Combustion Carbon Dioxide Capture for Existing Post-Combustion Boilers by Self-Concentrating Amine Absorbent CX(s)...

395

CX-012279: Categorical Exclusion Determination | Department of...  

Broader source: Energy.gov (indexed) [DOE]

CX-012279: Categorical Exclusion Determination Vertically Aligned Carbon-Nanotubes Embedded in Ceramic Matrices for Hot Electrode Applications CX(s) Applied: B3.6...

396

CX-011005: Categorical Exclusion Determination | Department of...  

Broader source: Energy.gov (indexed) [DOE]

CX-011005: Categorical Exclusion Determination Scalable, Automated, Semi permanent Seismic Method for Detecting Carbon Dioxide Plume Extent During Geological... CX(s) Applied:...

397

CX-011006: Categorical Exclusion Determination | Department of...  

Broader source: Energy.gov (indexed) [DOE]

CX-011006: Categorical Exclusion Determination Scalable, Automated, Semi Permanent Seismic Method for Detecting Carbon Dioxide Plume Extent During Geological... CX(s) Applied:...

398

CX-005037: Categorical Exclusion Determination | Department of...  

Broader source: Energy.gov (indexed) [DOE]

CX-005037: Categorical Exclusion Determination Field Test of Carbon Dioxide-Methane Method for Production of Gas Hydrate CX(s) Applied: B3.7 Date: 01142011...

399

CX-002604: Categorical Exclusion Determination | Department of...  

Broader source: Energy.gov (indexed) [DOE]

CX-002604: Categorical Exclusion Determination Characterization of Most Promising Carbon Capture and Sequestration Formations in the Central Rocky Mountain Region CX(s)...

400

CX-002605: Categorical Exclusion Determination | Department of...  

Broader source: Energy.gov (indexed) [DOE]

CX-002605: Categorical Exclusion Determination Characterization of Most Promising Carbon Capture and Sequestration Formations in the Central Rocky Mountain Region 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.


401

CX-000413: Categorical Exclusion Determination | Department of...  

Broader source: Energy.gov (indexed) [DOE]

CX-000413: Categorical Exclusion Determination Characterization of Most Promising Carbon Capture and Sequestration Formations in the Central Rocky Mountain Region CX(s)...

402

CX-000416: Categorical Exclusion Determination | Department of...  

Broader source: Energy.gov (indexed) [DOE]

CX-000416: Categorical Exclusion Determination Characterization of Most Promising Carbon Capture and Sequestration Formations in the Central Rocky Mountain Region CX(s)...

403

CX-000415: Categorical Exclusion Determination | Department of...  

Broader source: Energy.gov (indexed) [DOE]

CX-000415: Categorical Exclusion Determination Characterization of Most Promising Carbon Capture and Sequestration Formations in the Central Rocky Mountain Region CX(s)...

404

Scale Up of Novel, Low-Cost Carbon Fibers Leading to High-Volume...  

Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

More Documents & Publications CX-009154: Categorical Exclusion Determination Low Cost Carbon Fiber Research in the LM Materials Program Overview Carbon Fiber Technology...

405

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

SciTech Connect (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

406

Carbon Fiber  

ScienceCinema (OSTI)

Lee McGetrick leads ORNL's effort to produce light, durable carbon fiber at lower cost -- a key to improvements in manufacturing that will produce more fuel-efficient vehicles and other advances.

McGetrick, Lee

2014-07-23T23:59:59.000Z

407

Carbon Fiber  

SciTech Connect (OSTI)

Lee McGetrick leads ORNL's effort to produce light, durable carbon fiber at lower cost -- a key to improvements in manufacturing that will produce more fuel-efficient vehicles and other advances.

McGetrick, Lee

2014-04-17T23:59:59.000Z

408

Carbon Sequestration  

SciTech Connect (OSTI)

Carbon Sequestration- the process of capturing the CO2 released by the burning of fossil fuels and storing it deep withing the Earth, trapped by a non-porous layer of rock.

None

2013-05-06T23:59:59.000Z

409

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

SciTech Connect (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

410

Refined conceptual model for the Volatile Organic Compounds-Arid Integrated Demonstration and 200 West Area Carbon Tetrachloride Expedited Response Action  

SciTech Connect (OSTI)

This report presents a refined geohydrologic and geochemical conceptual model of the host site (Hanford Reservation) for the Volatile Organic Compounds -- Arid Integrated Demonstration (VOC-Arid ID) and 200 West Area Carbon Tetrachloride (CCl{sub 4}) Expedited Response Action (ERA), based on the results from fiscal year 1992 site characterization activities. The ERA was initiated in December 1990 to minimize or stabilize CCl{sub 4} migration within the unsaturated (vadose) zone in the vicinity of three CCl{sub 4} disposal sites in the 200 West Area (216-Z-1A tile field, 216-Z-9 trench, and 216-Z-18 crib). Implementation of this ERA was based on concerns that CCl{sub 4} residing in the soils was continuing to spread to the groundwater and, if left unchecked, would significantly increase the area of groundwater contamination. A soil-vapor-extraction system began operating at the site in February 1992.

Last, G.V. [Pacific Northwest Lab., Richland, WA (United States); Rohay, V.J. [Westinghouse Hanford Co., Richland, WA (United States)

1993-03-01T23:59:59.000Z

411

Carbon migration in 5Cr-0.5Mo/21Cr-12Ni dissimilar metal welds  

SciTech Connect (OSTI)

The carbon migration between a ferritic steel and an austenitic steel was studied in submerged arc-welded 5Cr-0.5Mo/21Cr-12Ni dissimilar metal welds (DMWs) after aging at 500 C for various times and after long-term service in technical practice. The distribution of carbon, chromium, nickel, and iron in the areas around the weld interface was determined by electron probe microanalysis, and the microstructural aspect in the carbon-depleted/enriched zone was characterized by optical microscopy and transmission electron microscopy (TEM). Furthermore, the precipitation sequences and composition characteristics of the carbides were identified by diffraction pattern microanalysis and energy-dispersive X-ray (EDX) microanalysis. It was found (1) that there exists a coherent relationship between intracrystalline M{sub 23}C{sub 6} and the austenitic matrix; (2) that the composition of M{sub 23}C{sub 6} in the carbon-enriched zone is independent of the duration of aging and service; (3) that the maximum carbon concentration is determined by the carbide type, the composition characteristic of precipitated carbides, and the concentration of carbide-forming Cr adjacent to the weld interface in the carbon-enriched zone; and (4) that the carbon migration in the 5Cr-0.5Mo/21Cr-12Ni DMWs can be described by a diffusion model.

Huang, M.L.; Wang, L. [Dalian Univ. of Technology (China). Dept. of Materials Engineering

1998-12-01T23:59:59.000Z

412

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

E-Print Network [OSTI]

(for water: the SPC-, SPC/E-, and TIP4P-potential models; for carbon dioxide: the EPM2 potential model dioxide are calculated. For water, the SPC- and TIP4P-models give superior results for the vapor pressure when compared to the SPC/E-model. The vapor liquid equilibrium of the binary mixture carbon dioxide

413

Source Term Modeling for Evaluating the Potential Impacts to Groundwater of Fluids Escaping from a Depleted Oil Reservoir Used for Carbon Sequestration  

SciTech Connect (OSTI)

In recent years depleted oil reservoirs have received special interest as carbon storage reservoirs because of their potential to offset costs through collaboration with enhanced oil recovery projects. Modeling is currently being conducted to evaluate potential risks to groundwater associated with leakage of fluids from depleted oil reservoirs used for storage of CO2. Modeling results reported here focused on understanding how toxic organic compounds found in oil will distribute between the various phases within a storage reservoir after introduction of CO2, understanding the migration potential of these compounds, and assessing potential groundwater impacts should leakage occur. Two model scenarios were conducted to evaluate how organic components in oil will distribute among the phases of interest (oil, CO2, and brine). The first case consisted of 50 wt.% oil and 50 wt.% water; the second case was 90 wt.% CO2 and 10 wt.% oil. Several key organic compounds were selected for special attention in this study based upon their occurrence in oil at significant concentrations, relative toxicity, or because they can serve as surrogate compounds for other more highly toxic compounds for which required input data are not available. The organic contaminants of interest (COI) selected for this study were benzene, toluene, naphthalene, phenanthrene, and anthracene. Partitioning of organic compounds between crude oil and supercritical CO2 was modeled using the Peng-Robinson equation of state over temperature and pressure conditions that represent the entire subsurface system (from those relevant to deep geologic carbon storage environments to near surface conditions). Results indicate that for a typical set of oil reservoir conditions (75C, and 21,520 kPa) negligible amounts of the COI dissolve into the aqueous phase. When CO2 is introduced into the reservoir such that the final composition of the reservoir is 90 wt.% CO2 and 10 wt.% oil, a significant fraction of the oil dissolves into the vapor phase. As the vapor phase moves up through the stratigraphic column, pressures and temperatures decrease, resulting in significant condensation of oil components. The heaviest organic components condense early in this process (at higher pressures and temperatures), while the lighter components tend to remain in the vapor phase until much lower pressures and temperatures are reached. Based on the model assumptions, the final concentrations of COI to reach an aquifer at 1,520 kPa and 25C were quite significant for benzene and toluene, whereas the concentrations of polynuclear aromatic hydrocarbons that reach the aquifer were very small. This work demonstrates a methodology that can provide COI source term concentrations in CO2 leaking from a reservoir and entering an overlying aquifer for use in risk assessments.

Cantrell, Kirk J.; Brown, Christopher F.

2014-06-13T23:59:59.000Z

414

Low Carbon Fuel Standards  

E-Print Network [OSTI]

gas, or even coal with carbon capture and sequestration. Afuels that facilitate carbon capture and sequestration. Forenergy and could capture and sequester carbon emissions.

Sperling, Dan; Yeh, Sonia

2009-01-01T23:59:59.000Z

415

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

SciTech Connect (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

416

Carbon supercapacitors  

SciTech Connect (OSTI)

Carbon supercapacitors are represented as distributed RC networks with transmission line equivalent circuits. At low charge/discharge rates and low frequencies these networks approximate a simple series R{sub ESR}C circuit. The energy efficiency of the supercapacitor is limited by the voltage drop across the ESR. The pore structure of the carbon electrode defines the electrochemically active surface area which in turn establishes the volume specific capacitance of the carbon material. To date, the highest volume specific capacitance reported for a supercapacitor electrode is 220F/cm{sup 3} in aqueous H{sub 2}SO{sub 4} (10) and {approximately}60 F/cm{sup 3} in nonaqueous electrolyte (8).

Delnick, F.M.

1993-11-01T23:59:59.000Z

417

CX-004132: Categorical Exclusion Determination | Department of...  

Broader source: Energy.gov (indexed) [DOE]

Exclusion Determination CX-004132: Categorical Exclusion Determination Low Cost Carbon Fiber Composites for Lightweight Vehicle Parts CX(s) Applied: B3.6, B5.1 Date: 09...

418

CX-011464: Categorical Exclusion Determination | Department of...  

Broader source: Energy.gov (indexed) [DOE]

Exclusion Determination CX-011464: Categorical Exclusion Determination Midwest Regional Carbon Sequestration Partnership - Subtask 1.7 CX(s) Applied: B3.1, B3.7 Date: 10312013...

419

CX-008505: Categorical Exclusion Determination | Department of...  

Broader source: Energy.gov (indexed) [DOE]

Exclusion Determination CX-008505: Categorical Exclusion Determination Midwest Regional Carbon Sequestration Partnership - Phase Three CX(s) Applied: B3.1, B5.3, B1.3 Date: 07...

420

CX-008508: Categorical Exclusion Determination | Department of...  

Broader source: Energy.gov (indexed) [DOE]

Exclusion Determination CX-008508: Categorical Exclusion Determination Midwest Regional Carbon Sequestration Partnership - Phase Three CX(s) Applied: B3.1, B5.3, B5.13 Date: 07...

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

CX-011810: Categorical Exclusion Determination | Department of...  

Broader source: Energy.gov (indexed) [DOE]

Exclusion Determination CX-011810: Categorical Exclusion Determination Midwest Regional Carbon Sequestration Partnership Phase III - Subtask 1.7 CX(s) Applied: B3.1, B3.7 Date:...

422

Marine transportation for Carbon Capture and Sequestration (CCS)  

E-Print Network [OSTI]

The objective of this report is to determine whether opportunities to use liquefied carbon dioxide carriers as part of a carbon capture and storage system will exist over the next twenty years. Factors that encourage or ...

Alexandrakis, Mary-Irene

2010-01-01T23:59:59.000Z

423

CX-002610: Categorical Exclusion Determination  

Broader source: Energy.gov [DOE]

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 KansasCX(s) Applied: B3.1, A9Date: 12/11/2009Location(s): Sumner County, KansasOffice(s): Fossil Energy, National Energy Technology Laboratory

424

CX-002613: Categorical Exclusion Determination  

Broader source: Energy.gov [DOE]

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 KansasCX(s) Applied: B3.1, A9Date: 12/11/2009Location(s): Sumner County, KansasOffice(s): Fossil Energy, National Energy Technology Laboratory

425

Carbon microtubes  

DOE Patents [OSTI]

A carbon microtube comprising a hollow, substantially tubular structure having a porous wall, wherein the microtube has a diameter of from about 10 .mu.m to about 150 .mu.m, and a density of less than 20 mg/cm.sup.3. Also described is a carbon microtube, having a diameter of at least 10 .mu.m and comprising a hollow, substantially tubular structure having a porous wall, wherein the porous wall comprises a plurality of voids, said voids substantially parallel to the length of the microtube, and defined by an inner surface, an outer surface, and a shared surface separating two adjacent voids.

Peng, Huisheng (Shanghai, CN); Zhu, Yuntian Theodore (Cary, NC); Peterson, Dean E. (Los Alamos, NM); Jia, Quanxi (Los Alamos, NM)

2011-06-14T23:59:59.000Z

426

Fractionation of stable carbon isotopes by phosphoenopyruvate carboxylase from C4 plants  

E-Print Network [OSTI]

-Slack pathway, the active species of carbon dioxide utilized by phosphoenolpyruvate carboxylase was determined. The initial velocity curves obtained when bicarbonate, carbon dioxide, or carbon dioxide and carbonic anhydrase were used to initiate... the reactions, support the conclusion that the bicarbonate ion is the active species of "C02" used. Initial velocities for bicarbonate, carbon dioxide and carbon dioxide with carbonic anhydrase were 696. 2, 69. 6, and 348. 1 umoles malate produced/min mg...

Reibach, Paul Howard

1976-01-01T23:59:59.000Z

427

Control of carbon balance in a silicon smelting furnace  

DOE Patents [OSTI]

The present invention is a process for the carbothermic reduction of silicon dioxide to form elemental silicon. Carbon balance of the process is assessed by measuring the amount of carbon monoxide evolved in offgas exiting the furnace. A ratio of the amount of carbon monoxide evolved and the amount of silicon dioxide added to the furnace is determined. Based on this ratio, the carbon balance of the furnace can be determined and carbon feed can be adjusted to maintain the furnace in carbon balance.

Dosaj, V.D.; Haines, C.M.; May, J.B.; Oleson, J.D.

1992-12-29T23:59:59.000Z

428

Carbon Storage Program  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Carbon Sequestration Partnership MSU . . . . . . . . . . . . . . . . . . . . . . . Montana State University MVA . . . . . . . . . . . . . . . . . . . . . . . Monitoring,...

429

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

E-Print Network [OSTI]

of existing generation technologies. Under a range of resource cost scenarios, most coal power plants would. We use a mixed-integer linear programming model ­ SWITCH ­ to analyze least- cost generation, storage be replaced by solar, wind, gas, and/or nuclear generation, with intermittent renewable sources providing

Kammen, Daniel M.

430

Carbon Additionality: Discussion Paper  

E-Print Network [OSTI]

ahead, and identifying the carbon pools and other green house gas emissions sources and savings coveredCarbon Additionality: A review Discussion Paper Gregory Valatin November 2009 Forest Research. Voluntary Carbon Standards American Carbon Registry Forest Carbon Project Standard (ACRFCPS) 27 Carbon

431

A Model for Parent-Teacher Collaboration to Promote Self-Determination in Young Children With Disabilities  

E-Print Network [OSTI]

(Powers et al., 1996; Warger, 2001). Provide parents with opportuni- ties to examine their behefs about self-determination and cultural values for their children (Luft, 2001). Many parents want their children to become more self-determined, so teach- ers...-determination of students with disdhilities. Korean Journal of Special Education, 38(4], 369-390. Luft, P. (2001). Multicultural competence in transition planning processes. In R- W. Flexer, T. J. Simmons, P. Luft, & R. M. Baer (Eds.), TYansition planning for sec- ondary...

Lee, Suk-Hyang; Palmer, Susan B.; Turnbull, Ann P.; Wehmeyer, Michael L.

2006-01-01T23:59:59.000Z

432

CX-011119: Categorical Exclusion Determination  

Broader source: Energy.gov [DOE]

Physics-Based Reliability Models for Supercritical-Carbon Dioxide Turbomachinery Components CX(s) Applied: A9, B3.6 Date: 08/30/2013 Location(s): New York Offices(s): Golden Field Office

433

CX-008441: Categorical Exclusion Determination  

Broader source: Energy.gov [DOE]

Modeling Carbon Dioxide Sequestration in Saline Aquifer and Depleted Oil Reservoir (Task 17 - Office Work) CX(s) Applied: A9, A11 Date: 06/26/2012 Location(s): Kansas Offices(s): National Energy Technology Laboratory

434

CX-008440: Categorical Exclusion Determination  

Broader source: Energy.gov [DOE]

Modeling Carbon Dioxide Sequestration in Saline Aquifer and Depleted Oil Reservoir (Task 17 - Seismic Survey) CX(s) Applied: B3.1 Date: 06/26/2012 Location(s): Kansas Offices(s): National Energy Technology Laboratory

435

E-Print Network 3.0 - activated carbon based Sample Search Results  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

carbon credits, it is absolutely essential... not credit any soil carbon changes to the bioenergy crops. A second ... Source: Argonne National Laboratory - GREET Model Project...

436

E-Print Network 3.0 - assessing soil carbon Sample Search Results  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

of potential soil carbon change with an Integrated Assessment model... change on soil carbon sequestration Contact: Tris West, westto@ornl.gov, 865-574-7322 Field...

437

Carbon and carbon monoxide hydrogenation on nickel: support effects  

SciTech Connect (OSTI)

Hydrogenation of carbon, deposited on nickel catalysts by CO disproportionation, was investigated by temperature-programmed surface reaction (TPSR) for four oxide supports, alumina (Al/sub 2/O/sub 3/), silica (SiO/sub 2/), titanium oxide (TiO/sub 2/), and SiO/sub 2/.Al/sub 2/O/sub 3/. The rate of carbon monoxide hydrogenation was measured by temperature-programmed reaction (TPR) for comparison. The rate of carbon hydrogenation to methane was found to be independent of the support and an average activation energy of 42 kJ/mol was estimated. In contrast, the rate of carbon monoxide hydrogenation was very sensitive to the catalyst support. Nickel (Ni) supported on TiO/sub 2/ exhibited the highest specific activity, and two distinct sites for methanation were observed on Ni/TiO/sub 2/ and Ni/Al/sub 2/O/sub 3/. The lowest specific activities were observed for Ni/SiO/sub 2/ and Ni/SiO/sub 2/.Al/sub 2/O/sub 3/. For all catalysts, carbon hydrogenation occurred at a lower temperature than carbon monoxide hydrogenation. For both TPR and TPSR, small amounts of ethane were formed and at a lower temperature than methane. The amount of less-active, ..beta..-carbon observed in TPSR experiments was very small on all catalysts. These results indicate that at high coverages, carbon hydrogenation does not depend on the support, and thus it is not rate-determining for CO hydrogenation in excess hydrogen. The support is also shown to change the specific rate of carbon monoxide methanation; activity differences seen in steady-state experiments are not just due to differences in site densities. 5 figures, 5 tables.

Ozdogan, S.Z.; Gochis, P.D.; Falconer, J.L.

1983-10-01T23:59:59.000Z

438

Carbon Trading, Carbon Taxes and Social Discounting  

E-Print Network [OSTI]

Carbon Trading, Carbon Taxes and Social Discounting Elisa Belfiori belf0018@umn.edu University of Minnesota Abstract This paper considers the optimal design of policies to carbon emissions in an economy, such as price or quantity controls on the net emissions of carbon, are insufficient to achieve the social

Weiblen, George D

439

Dynamic Jiles-Atherton Model for Determining the Magnetic Power Loss at High Frequency in Permanent Magnet Machines  

E-Print Network [OSTI]

BH curves at frequencies up to several kilohertz. B. Application of the Dynamic Jiles-Atherton Model to the Magnetic Loss of a PMSM (BLDC motor) According to Guos review paper, empirical formulae have been derived to model the magnetic properties... of the conventional time stepped FEM [11], [26], [27] to utilize the proposed dynamic Jiles-Atherton model to estimate the magnetic power loss in a PMSM. More mathematical work needs to be done to make the dynamic Jiles-Atherton model and time stepped FEM...

Du, Ruoyang; Student Member; IEEE; Robertson, Paul

2014-12-18T23:59:59.000Z

440

The determination of regionalised wind roses for the UK, for use with the HARM acid depositional model.  

E-Print Network [OSTI]

Metcalfe Dr. Claire Jarvis & Dr. Jim Nicholson #12;Abstract- The Hull acid rain (HARM) depositional model of Geography) is not permitted. #12;1 INTRODUCTION The Hull acid rain (HARM) Lagrangian receptor depositional, 2002, p1 & 6). Other acid rain models that use the Lagrangian receptor technique such as the original

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

QUANTIFYING FOREST ABOVEGROUND CARBON POOLS AND FLUXES USING MULTI-TEMPORAL LIDAR A report on field monitoring, remote sensing MMV, GIS integration, and modeling results for forestry field validation test to quantify aboveground tree biomass and carbon  

SciTech Connect (OSTI)

Sound policy recommendations relating to the role of forest management in mitigating atmospheric carbon dioxide (CO{sub 2}) depend upon establishing accurate methodologies for quantifying forest carbon pools for large tracts of land that can be dynamically updated over time. Light Detection and Ranging (LiDAR) remote sensing is a promising technology for achieving accurate estimates of aboveground biomass and thereby carbon pools; however, not much is known about the accuracy of estimating biomass change and carbon flux from repeat LiDAR acquisitions containing different data sampling characteristics. In this study, discrete return airborne LiDAR data was collected in 2003 and 2009 across {approx}20,000 hectares (ha) of an actively managed, mixed conifer forest landscape in northern Idaho, USA. Forest inventory plots, established via a random stratified sampling design, were established and sampled in 2003 and 2009. The Random Forest machine learning algorithm was used to establish statistical relationships between inventory data and forest structural metrics derived from the LiDAR acquisitions. Aboveground biomass maps were created for the study area based on statistical relationships developed at the plot level. Over this 6-year period, we found that the mean increase in biomass due to forest growth across the non-harvested portions of the study area was 4.8 metric ton/hectare (Mg/ha). In these non-harvested areas, we found a significant difference in biomass increase among forest successional stages, with a higher biomass increase in mature and old forest compared to stand initiation and young forest. Approximately 20% of the landscape had been disturbed by harvest activities during the six-year time period, representing a biomass loss of >70 Mg/ha in these areas. During the study period, these harvest activities outweighed growth at the landscape scale, resulting in an overall loss in aboveground carbon at this site. The 30-fold increase in sampling density between the 2003 and 2009 did not affect the biomass estimates. Overall, LiDAR data coupled with field reference data offer a powerful method for calculating pools and changes in aboveground carbon in forested systems. The results of our study suggest that multitemporal LiDAR-based approaches are likely to be useful for high quality estimates of aboveground carbon change in conifer forest systems.

Lee Spangler; Lee A. Vierling; Eva K. Stand; Andrew T. Hudak; Jan U.H. Eitel; Sebastian Martinuzzi

2012-04-01T23:59:59.000Z

442

Computational Geosciences Improved Semi-Analytical Simulation of Geological Carbon Sequestration  

E-Print Network [OSTI]

Computational Geosciences Improved Semi-Analytical Simulation of Geological Carbon Sequestration of Geological Carbon Sequestration Article Type: Manuscript Keywords: Semi-Analytical Modeling; Iterative Methods; Geological Carbon Sequestration; Injection Site Assessment Corresponding Author: Brent Cody

Bau, Domenico A.

443

Public Review Draft: A Method for Assessing Carbon Stocks, Carbon  

E-Print Network [OSTI]

Public Review Draft: A Method for Assessing Carbon Stocks, Carbon Sequestration, and Greenhouse, and Zhu, Zhiliang, 2010, Public review draft; A method for assessing carbon stocks, carbon sequestration

444

Carbon-Optimal and Carbon-Neutral Supply Chains  

E-Print Network [OSTI]

Li, M. Daskin. 2009. Carbon Footprint and the Management ofThe Importance of Carbon Footprint Estimation Boundaries.Carbon accounting and carbon footprint - more than just

Caro, F.; Corbett, C. J.; Tan, T.; Zuidwijk, R.

2011-01-01T23:59:59.000Z

445

Enhanced Performance Assessment System (EPAS) for carbon sequestration.  

SciTech Connect (OSTI)

Carbon capture and sequestration (CCS) is an option to mitigate impacts of atmospheric carbon emission. Numerous factors are important in determining the overall effectiveness of long-term geologic storage of carbon, including leakage rates, volume of storage available, and system costs. Recent efforts have been made to apply an existing probabilistic performance assessment (PA) methodology developed for deep nuclear waste geologic repositories to evaluate the effectiveness of subsurface carbon storage (Viswanathan et al., 2008; Stauffer et al., 2009). However, to address the most pressing management, regulatory, and scientific concerns with subsurface carbon storage (CS), the existing PA methodology and tools must be enhanced and upgraded. For example, in the evaluation of a nuclear waste repository, a PA model is essentially a forward model that samples input parameters and runs multiple realizations to estimate future consequences and determine important parameters driving the system performance. In the CS evaluation, however, a PA model must be able to run both forward and inverse calculations to support optimization of CO{sub 2} injection and real-time site monitoring as an integral part of the system design and operation. The monitoring data must be continually fused into the PA model through model inversion and parameter estimation. Model calculations will in turn guide the design of optimal monitoring and carbon-injection strategies (e.g., in terms of monitoring techniques, locations, and time intervals). Under the support of Laboratory-Directed Research & Development (LDRD), a late-start LDRD project was initiated in June of Fiscal Year 2010 to explore the concept of an enhanced performance assessment system (EPAS) for carbon sequestration and storage. In spite of the tight time constraints, significant progress has been made on the project: (1) Following the general PA methodology, a preliminary Feature, Event, and Process (FEP) analysis was performed for a hypothetical CS system. Through this FEP analysis, relevant scenarios for CO{sub 2} release were defined. (2) A prototype of EPAS was developed by wrapping an existing multi-phase, multi-component reservoir simulator (TOUGH2) with an uncertainty quantification and optimization code (DAKOTA). (3) For demonstration, a probabilistic PA analysis was successfully performed for a hypothetical CS system based on an existing project in a brine-bearing sandstone. The work lays the foundation for the development of a new generation of PA tools for effective management of CS activities. At a top-level, the work supports energy security and climate change/adaptation by furthering the capability to effectively manage proposed carbon capture and sequestration activities (both research and development as well as operational), and it greatly enhances the technical capability to address this national problem. The next phase of the work will include (1) full capability demonstration of the EPAS, especially for data fusion, carbon storage system optimization, and process optimization of CO{sub 2} injection, and (2) application of the EPAS to actual carbon storage systems.

Wang, Yifeng; Sun, Amy Cha-Tien; McNeish, Jerry A. (Sandia National Laboratories, Livermore, CA); Dewers, Thomas A.; Hadgu, Teklu; Jove-Colon, Carlos F.

2010-09-01T23:59:59.000Z

446

Vibration, buckling and impact of carbon nanotubes.  

E-Print Network [OSTI]

??Natural frequencies of the double and triple-walled carbon nanotubes are determined exactly and approximately for both types. Approximate solutions are found by using Bubnov-Galerkin and (more)

Pentaras, Demetris.

2009-01-01T23:59:59.000Z

447

Implementation and Evaluation of the Virtual Fields Method: Determining Constitutive Model Parameters From Full-Field Deformation Data.  

SciTech Connect (OSTI)

The Virtual Fields Method (VFM) is an inverse method for constitutive model parameter identication that relies on full-eld experimental measurements of displacements. VFM is an alternative to standard approaches that require several experiments of simple geometries to calibrate a constitutive model. VFM is one of several techniques that use full-eld exper- imental data, including Finite Element Method Updating (FEMU) techniques, but VFM is computationally fast, not requiring iterative FEM analyses. This report describes the im- plementation and evaluation of VFM primarily for nite-deformation plasticity constitutive models. VFM was successfully implemented in MATLAB and evaluated using simulated FEM data that included representative experimental noise found in the Digital Image Cor- relation (DIC) optical technique that provides full-eld displacement measurements. VFM was able to identify constitutive model parameters for the BCJ plasticity model even in the presence of simulated DIC noise, demonstrating VFM as a viable alternative inverse method. Further research is required before VFM can be adopted as a standard method for constitu- tive model parameter identication, but this study is a foundation for ongoing research at Sandia for improving constitutive model calibration.

Kramer, Sharlotte Lorraine Bolyard; Scherzinger, William M.

2014-09-01T23:59:59.000Z

448

Risk-Informed Monitoring, Verification and Accounting (RI-MVA). An NRAP White Paper Documenting Methods and a Demonstration Model for Risk-Informed MVA System Design and Operations in Geologic Carbon Sequestration  

SciTech Connect (OSTI)

This white paper accompanies a demonstration model that implements methods for the risk-informed design of monitoring, verification and accounting (RI-MVA) systems in geologic carbon sequestration projects. The intent is that this model will ultimately be integrated with, or interfaced with, the National Risk Assessment Partnership (NRAP) integrated assessment model (IAM). The RI-MVA methods described here apply optimization techniques in the analytical environment of NRAP risk profiles to allow systematic identification and comparison of the risk and cost attributes of MVA design options.

Unwin, Stephen D.; Sadovsky, Artyom; Sullivan, E. C.; Anderson, Richard M.

2011-09-30T23:59:59.000Z

449

Belowground Carbon Cycling Processes at the Molecular Scale: An EMSL Science Theme Advisory Panel Workshop  

SciTech Connect (OSTI)

As part of the Belowground Carbon Cycling Processes at the Molecular Scale workshop, an EMSL Science Theme Advisory Panel meeting held in February 2013, attendees discussed critical biogeochemical processes that regulate carbon cycling in soil. The meeting attendees determined that as a national scientific user facility, EMSL can provide the tools and expertise needed to elucidate the molecular foundation that underlies mechanistic descriptions of biogeochemical processes that control carbon allocation and fluxes at the terrestrial/atmospheric interface in landscape and regional climate models. Consequently, the workshop's goal was to identify the science gaps that hinder either development of mechanistic description of critical processes or their accurate representation in climate models. In part, this report offers recommendations for future EMSL activities in this research area. The workshop was co-chaired by Dr. Nancy Hess (EMSL) and Dr. Gordon Brown (Stanford University).

Hess, Nancy J.; Brown, Gordon E.; Plata, Charity

2014-02-21T23:59:59.000Z

450

A Risk-Based System Analysis Framework for Geological Carbon Sequestration.  

SciTech Connect (OSTI)

The purpose of this project was to characterize existing carbon capture and sequestration technologies at a high level, develop an analytical framework to help assess the technologies, and implement the framework in a system dynamics model. The first year of this project succeeded in characterizing existing technologies to help focus the analysis on power plants. The assessment also helped determine which technologies are largely accepted by the carbon capture research community as relatively proven technologies, discuss the salient performance metrics, and assess the associated economics. With this information, an analytical framework was developed to assess the technologies from a systems view perspective. With this framework, the Carbon Sequestration and Risk Model (CSR) was developed to assess performance and economic risk issues as they relate to global atmospheric CO2 concentration goals and single plant scale projects to characterize the economics of these systems.

Kobos, Peter H.; Klotz, Richard

2006-10-01T23:59:59.000Z

451

Semi-analytical model of brine and CO2 leakage through an abandoned plugged well. Applications for determining an Area of Review and CO2 leakage rate  

E-Print Network [OSTI]

Semi-analytical model of brine and CO2 leakage through an abandoned plugged well. Applications for determining an Area of Review and CO2 leakage rate Arnaud Réveillère, Jérémy Rohmer, Frédéric Wertz / contact the leak, and of CO2,g as a first approach. Compared to the state of the art, it adds the possibility

Paris-Sud XI, Université de

452

Determining Greenland Ice Sheet sensitivity to regional climate change: one-way coupling of a 3-D thermo-mechanical ice sheet model with a mesoscale climate model  

E-Print Network [OSTI]

in running RCMs over Greenland to produce high-qualityoutlet glaciers. For Greenland, this detail is specificallyCurrently, no coupled Greenland Ice Sheet model experiment

Schlegel, Nicole-Jeanne

2011-01-01T23:59:59.000Z

453

DEVELOPING A SET OF REGULATORY ANALOGS FOR CARBON SEQUESTRATION  

E-Print Network [OSTI]

DEVELOPING A SET OF REGULATORY ANALOGS FOR CARBON SEQUESTRATION D.M. Reiner1 , H.J. Herzog2 1 Judge Avenue, Cambridge, MA 02139, USA, email: hjherzog@mit.edu ABSTRACT Carbon capture and sequestration variables critical for determining the success of carbon sequestration as a viable climate policy option

454

A SEARCH FOR REGULATORY ANALOGS TO CARBON SEQUESTRATION  

E-Print Network [OSTI]

A SEARCH FOR REGULATORY ANALOGS TO CARBON SEQUESTRATION D.M. Reiner and H.J. Herzog1 1 Laboratory for Energy and the Environment, M.I.T., Cambridge, MA. 02139, USA ABSTRACT Carbon capture and sequestration for determining the success of carbon sequestration as a viable climate policy option. INTRODUCTION To date

455

Analysis of Strategies of Companies under Carbon Constraint: Relationship between Profit Structure of Companies and Carbon/Fuel Price Uncertainty  

E-Print Network [OSTI]

This paper examines the relationship between future carbon prices and the expected profit of companies by case studies with model companies. As the future carbon price will vary significantly in accordance with the political ...

Hashimoto, Susumu

456

Comprehensive model to determine the effects of temperature and species fluctuations on reaction rates in turbulent reaction flows  

SciTech Connect (OSTI)

The use of silane (SiH4) as an effective ignitor and flame stabilizing pilot fuel is well documented. A reliable chemical kinetic mechanism for prediction of its behavior at the conditions encountered in the combustor of a SCRAMJET engine was calculated. The effects of hydrogen addition on hydrocarbon ignition and flame stabilization as a means for reduction of lengthy ignition delays and reaction times were studied. The ranges of applicability of chemical kinetic models of hydrogen-air combustors were also investigated. The CHARNAL computer code was applied to the turbulent reaction rate modeling.

Magnotti, F.; Diskin, G.; Matulaitis, J.; Chinitz, W.

1984-01-01T23:59:59.000Z

457

PUBLISHED ONLINE: XX MONTH XXXX | DOI: 10.1038/NCLIMATE1951 Global soil carbon projections are improved by  

E-Print Network [OSTI]

Society relies on Earth system models (ESMs) to project future climate and carbon cycle feedbacks. However

German, Donovan P.

458

PUBLISHED ONLINE: 28 JULY 2013 | DOI: 10.1038/NCLIMATE1951 Global soil carbon projections are improved by  

E-Print Network [OSTI]

Society relies on Earth system models (ESMs) to project future climate and carbon (C) cycle feedbacks

Saleska, Scott

459

Integrated thermal-microstructure model to predict the property gradients in resistance spot steel welds  

SciTech Connect (OSTI)

An integrated model approach was proposed for relating resistance welding parameters to weldment properties. An existing microstructure model was used to determine the microstructural and property gradients in resistance spot welds of plain carbon steel. The effect of these gradients on the weld integrity was evaluated with finite element analysis. Further modifications to this integrated thermal-microstructure model are discussed.

Babu, S.S.; Riemer, B.W.; Santella, M.L. [Oak Ridge National Lab., TN (United States); Feng, Z. [Edison Welding Inst., Columbus, OH (United States)

1998-11-01T23:59:59.000Z

460

CX-001424: Categorical Exclusion Determination | Department of...  

Broader source: Energy.gov (indexed) [DOE]

Determination CX-001424: Categorical Exclusion Determination Thermal-Hydrological-Mechanical-Chemical Modeling of Enhanced Geothermal System Reservoirs - Continuum through...

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.


461

Photophysics of carbon nanotubes  

E-Print Network [OSTI]

This thesis reviews the recent advances made in optical studies of single-wall carbon nanotubes. Studying the electronic and vibrational properties of carbon nanotubes, we find that carbon nanotubes less than 1 nm in ...

Samsonidze, Georgii G

2007-01-01T23:59:59.000Z

462

CALIFORNIA CARBON SEQUESTRATION THROUGH  

E-Print Network [OSTI]

CALIFORNIA ENERGY COMMISSION CARBON SEQUESTRATION THROUGH CHANGES IN LAND USE IN WASHINGTON. Carbon Sequestration Through Changes in Land Use in Washington: Costs and Opportunities. California for Terrestrial Carbon Sequestration in Oregon. Report to Winrock International. #12;ii #12;iii Preface

463

Where do fossil fuel carbon dioxide emissions from California go? An analysis based on radiocarbon observations and an atmospheric transport model  

E-Print Network [OSTI]

independent budgeting of fossil fuel CO 2 over Europe by (CO2008), Where do fossil fuel carbon dioxide emissions from2004), Estimates of annual fossil-fuel CO 2 emitted for each

2008-01-01T23:59:59.000Z

464

Where do fossil fuel carbon dioxide emissions from California go? An analysis based on radiocarbon observations and an atmospheric transport model  

E-Print Network [OSTI]

independent budgeting of fossil fuel CO 2 over Europe by (CO2008 Where do fossil fuel carbon dioxide emissions frompatterns and mixing of fossil fuel-derived CO 2 is important

2008-01-01T23:59:59.000Z

465

Method of making carbon-carbon composites  

DOE Patents [OSTI]

A process for making 2D and 3D carbon-carbon composites having a combined high crystallinity, high strength, high modulus and high thermal and electrical conductivity. High-modulus/high-strength mesophase derived carbon fibers are woven into a suitable cloth. Layers of this easily graphitizible woven cloth are infiltrated with carbon material to form green composites. The carbonized composite is then impregnated several times with pitch by covering the composite with hot pitch under pressure. The composites are given a heat treatment between each impregnant step to crack up the infiltrated carbon and allow additional pitch to enter the microstructure during the next impregnation cycle. The impregnated composites are then given a final heat treatment in the range 2500.degree. to 3100.degree. C. to fully graphitize the fibers and the matrix carbon. The composites are then infiltrated with pyrolytic carbon by chemical vapor deposition in the range 1000.degree. C. to 1300.degree. C. at a reduced. pressure.

Engle, Glen B. (16716 Martincoit Rd., Poway, CA 92064)

1993-01-01T23:59:59.000Z

466

A novel method to develop an otolith microchemistry model to determine striped bass habitat use in the San Francisco Estuary  

SciTech Connect (OSTI)

Otolith Sr/Ca has become a popular tool for hind casting habitat utilization and migration histories of euryhaline fish. It can readily identify habitat shifts of diadromous fish in most systems. Inferring movements of fish within estuarine habitat, however, requires a model of that accounts of the local water chemistry and the response of individual species to that water chemistry, which is poorly understood. Modeling is further complicated by the fact that high marine Sr and Ca concentrations results in a rapid, nonlinear increase in water Sr/Ca and {sup 87}Sr/{sup 86}Sr between fresh and marine waters. Here we demonstrate a novel method for developing a salinity-otolith Sr/Ca model for the purpose of reconstructing striped bass (Morone saxatilis) habitat use in the San Francisco Bay estuary. We used correlated Sr/Ca and {sup 87}Sr/{sup 86}Sr ratios measurements from adult otoliths from striped bass that experienced a range of salinities to infer striped bass otolith Sr/Ca response to changes in salinity and water Sr/Ca ratio. Otolith {sup 87}Sr/{sup 86}Sr can be assumed to accurately record water {sup 87}Sr/{sup 86}Sr because there is no biological fractionation of Sr isotopes. Water {sup 87}Sr/{sup 86}Sr can in turn be used to estimate water salinity based on the mixing of fresh and marine water with known {sup 87}Sr/{sup 86}Sr ratios. The relationship between adjacent analyses on otoliths of Sr/Ca and {sup 87}Sr/{sup 86}Sr by LA-ICP-MS and MC-ICP-MS (r{sup 2} = 0.65, n = 66) is used to predict water salinity from a measured Sr/Ca ratio. The nature of this non-linear model lends itself well to identifying residence in the Delta and to a lesser extent Suisun Bay, but does not do well locating residence within the more saline bays west of Carquinez Strait. An increase in the number of analyses would improve model confidence, but ultimately the precision of the model is limited by the variability in the response of individual fish to water Sr/Ca.

Phillis, C C; Ostrach, D J; Gras, M; Yin, Q; Ingram, B L; Zinkl, J G; Weber, P K

2006-06-14T23:59:59.000Z

467

Toward Zero Carbon Energy Production Toward Zero Carbon Energy Production  

E-Print Network [OSTI]

#12;Toward Zero Carbon Energy Production Toward Zero Carbon Energy Production Toward Zero Carbon Energy Production Toward Zero Carbon Energy Production Toward Zero Carbon Energy Production Toward Zero Carbon Energy Production Toward Zero Carbon Energy Production Toward Zero Carbon Energy Production Toward

Narasayya, Vivek

468

Carbon Code Requirements for voluntary carbon sequestration projects  

E-Print Network [OSTI]

Woodland Carbon Code Requirements for voluntary carbon sequestration projects ® Version 1.2 July trademark 10 3. Carbon sequestration 11 3.1 Units of carbon calculation 11 3.2 Carbon baseline 11 3.3 Carbon leakage 12 3.4 Project carbon sequestration 12 3.5 Net carbon sequestration 13 4. Environmental quality 14

469

Low Carbon Fuel Standards  

E-Print Network [OSTI]

in 1990. These many alternative-fuel initiatives failed tolow-cost, low-carbon alternative fuels would thrive. Theto introduce low-carbon alternative fuels. Former Federal

Sperling, Dan; Yeh, Sonia

2009-01-01T23:59:59.000Z

470

Vacancy diffusion in colloidal crystals as determined by dynamical density-functional theory and the phase-field-crystal model  

E-Print Network [OSTI]

A two-dimensional crystal of repulsive dipolar particles is studied in the vicinity of its melting transition by using Brownian dynamics computer simulation, dynamical density functional theory and phase-field crystal modelling. A vacancy is created by taking out a particle from an equilibrated crystal and the relaxation dynamics of the vacancy is followed by monitoring the time-dependent one-particle density. We find that the vacancy is quickly filled up by diffusive hopping of neighbouring particles towards the vacancy center. We examine the temperature dependence of the diffusion constant and find that it decreases with decreasing temperature in the simulations. This trend is reproduced by the dynamical density functional theory. Conversely, the phase field crystal calculations predict the opposite trend. Therefore, the phase-field model needs a temperature-dependent expression for the mobility to predict trends correctly.

Sven van Teeffelen; Cristian Vasile Achim; Hartmut Lwen

2013-02-05T23:59:59.000Z

471

Carbon Capture (Carbon Cycle 2.0)  

ScienceCinema (OSTI)

Berend Smit speaks at the Carbon Cycle 2.0 kick-off symposium Feb. 3, 2010. We emit more carbon into the atmosphere than natural processes are able to remove - an imbalance with negative consequences. Carbon Cycle 2.0 is a Berkeley Lab initiative to provide the science needed to restore this balance by integrating the Labs diverse research activities and delivering creative solutions toward a carbon-neutral energy future. http://carboncycle2.lbl.gov/

Smit, Berend

2011-06-08T23:59:59.000Z

472

Structure of middle distillate fuels on the atomic carbon and hydrogen to carbon ratio at alpha position to aromatic rings  

SciTech Connect (OSTI)

The alkyl, naphthenic, or total carbon atoms of the functional groups at alpha position to aromatic rings and their hydrogen to carbon ratio are some of the important parameters for structural analysis of fossil fuel products. In this paper, the authors present a number of novel formula-structure relationships for precise determination of different carbon atom types at alpha position to aromatic rings and the average number of hydrogens per alpha-carbon.

Glavincevski, B.; Gulder, O.L.; Gardner, L

1988-01-01T23:59:59.000Z

473

ASSESSMENT OF HOUSEHOLD CARBON FOOTPRINT REDUCTION POTENTIALS  

SciTech Connect (OSTI)

The term ?household carbon footprint? refers to the total annual carbon emissions associated with household consumption of energy, goods, and services. In this project, Lawrence Berkeley National Laboratory developed a carbon footprint modeling framework that characterizes the key underlying technologies and processes that contribute to household carbon footprints in California and the United States. The approach breaks down the carbon footprint by 35 different household fuel end uses and 32 different supply chain fuel end uses. This level of end use detail allows energy and policy analysts to better understand the underlying technologies and processes contributing to the carbon footprint of California households. The modeling framework was applied to estimate the annual home energy and supply chain carbon footprints of a prototypical California household. A preliminary assessment of parameter uncertainty associated with key model input data was also conducted. To illustrate the policy-relevance of this modeling framework, a case study was conducted that analyzed the achievable carbon footprint reductions associated with the adoption of energy efficient household and supply chain technologies.

Kramer, Klaas Jan; Homan, Gr