National Library of Energy BETA

Sample records for kinetic en ergy

  1. SunErgy AE | Open Energy Information

    Open Energy Info (EERE)

    expanding it. SunErgy AE is a company located in Thessaloniki, Greece . http:www.rtl-hessen.devideos.php?video7202&kategorie25 http:www.giessener-allgemeine.deHomeStadt...

  2. MinnErgy LLC | Open Energy Information

    Open Energy Info (EERE)

    Winona, Minnesota Zip: 55987 Product: MinnErgy is a development stage Minnesota-based firm created for a planned ethanol project. Coordinates: 38.046946, -80.992255 Show Map...

  3. ErgyCapital Beghelli JV | Open Energy Information

    Open Energy Info (EERE)

    & Beghelli JV Place: Italy Product: Italy-based JV, formed to design and install photovoltaic systems. References: ErgyCapital & Beghelli JV1 This article is a stub. You can...

  4. ErgyCapital SpA formerly Greenergy Capital | Open Energy Information

    Open Energy Info (EERE)

    SpA formerly Greenergy Capital Jump to: navigation, search Name: ErgyCapital SpA (formerly Greenergy Capital) Place: Milan, Italy Zip: 20121 Sector: Efficiency, Renewable Energy...

  5. Inverse Kinetics

    Energy Science and Technology Software Center (OSTI)

    2000-03-20

    Given the space-independent, one energy group reactor kinetics equations and the initial conditions, this prgram determines the time variation of reactivity required to produce the given input of flux-time data.

  6. Combustion Kinetics

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

    Kinetics - Sandia Energy Energy Search Icon Sandia Home Locations Contact Us Employee Locator Energy & Climate Secure & Sustainable Energy Future Stationary Power Energy Conversion Efficiency Solar Energy Wind Energy Water Power Supercritical CO2 Geothermal Natural Gas Safety, Security & Resilience of the Energy Infrastructure Energy Storage Nuclear Power & Engineering Grid Modernization Battery Testing Nuclear Energy Defense Waste Management Programs Advanced Nuclear Energy

  7. AAMMo

    Gasoline and Diesel Fuel Update (EIA)

    "Nuclear Power Plant Performance: The Post-Three-Mile-Island Era," En- 67Jon Healey, "Panel Shifts Course on Nuclear Fund," Congressional ergyEconomics (July 1992), pp....

  8. A B

    U.S. Energy Information Administration (EIA) Indexed Site

    Consumption Survey: Consumption of Energy, 1985 This report, the first of a series based on the 1985 MECS, provides a comprehensive description of en ergy consumption by...

  9. Creating an Energy Awareness Campaign - A Handbook for Federal...

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

    n t li b a f Creating an EnErgy AwArEnEss ProgrAm A HAnDBooK For FEDErAL EnErgy mAnAgErs Energy Efficiency Renewable Energy is c ean, abu U.S. Department of Energy and Bringing you ...

  10. Chemical Kinetic Modelling

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

    Kinetic Modelling for Combustion Prof. Henry Curran 1 Copyright ©2016 by Prof Henry Curran. This material is not to be sold, reproduced or distributed without prior written permission of the owner, Prof Henry Curran. 2 Overview/Aims 5 days / 15 lectures Day 1 (1-3) Basic thermodynamic principles Day 2 (4) Basic kinetic principles (5,6) Experimental JSR, FR, RCM & ST contribution to kinetics Day 3 (7-9) Small species mechanism development 3 Overview/Aims 5 days /

  11. Eco Kinetics | Open Energy Information

    Open Energy Info (EERE)

    Kinetics Jump to: navigation, search Name: eco-Kinetics Place: Stapylton, Queensland, Australia Zip: 4207 Sector: Renewable Energy Product: Queensland-based renewable energy...

  12. 2. Chemical Kinetics

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

    1 Lecture) Chung K. Law Robert H. Goddard Professor Princeton University Princeton-CEFRC-Combustion Institute Summer School on Combustion June 20-24, 2016 1 Day 1: Chemical Thermodynamics and Kinetics 1. Chemical Thermodynamics * Chemical equilibrium * Energy conservation & adiabatic flame temp., T ad 2. Chemical Kinetics * Reaction rates and approximations * Theories of reaction rates * Straight and branched chain reactions 3. Oxidation Mechanisms of Fuels * Hydrogen, CO, hydrocarbons 2 1.

  13. Erbium hydride decomposition kinetics.

    SciTech Connect (OSTI)

    Ferrizz, Robert Matthew

    2006-11-01

    Thermal desorption spectroscopy (TDS) is used to study the decomposition kinetics of erbium hydride thin films. The TDS results presented in this report are analyzed quantitatively using Redhead's method to yield kinetic parameters (E{sub A} {approx} 54.2 kcal/mol), which are then utilized to predict hydrogen outgassing in vacuum for a variety of thermal treatments. Interestingly, it was found that the activation energy for desorption can vary by more than 7 kcal/mol (0.30 eV) for seemingly similar samples. In addition, small amounts of less-stable hydrogen were observed for all erbium dihydride films. A detailed explanation of several approaches for analyzing thermal desorption spectra to obtain kinetic information is included as an appendix.

  14. Paint decontamination kinetics

    SciTech Connect (OSTI)

    Thornton, E.W.

    1984-04-01

    Decontamination kinetics of a high-gloss polyurethane paint have been investigated using a novel flow cell experiment where the sample was counted in situ during decontamination. The /sup 134/Cs, /sup 137/Cs, and /sup 90/Y decontaminations follow a rate law that can be predicted theoretically for contaminant ion desorption from weakly heterogeneous random surface adsorption sites. Paint surfaces show the same decontamination kinetics after damage by abrasion or ultraviolet irradiation prior to contamination. The systems investigated exhibit Freundlich adsorption isotherm behavior during contamination; this is also characteristic of weakly heterogeneous random surfaces and is very commonly observed in ion adsorption studies at low concentrations.

  15. LLNL Chemical Kinetics Modeling Group

    SciTech Connect (OSTI)

    Pitz, W J; Westbrook, C K; Mehl, M; Herbinet, O; Curran, H J; Silke, E J

    2008-09-24

    The LLNL chemical kinetics modeling group has been responsible for much progress in the development of chemical kinetic models for practical fuels. The group began its work in the early 1970s, developing chemical kinetic models for methane, ethane, ethanol and halogenated inhibitors. Most recently, it has been developing chemical kinetic models for large n-alkanes, cycloalkanes, hexenes, and large methyl esters. These component models are needed to represent gasoline, diesel, jet, and oil-sand-derived fuels.

  16. 2. Chemical Kinetics

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

    Chung K. Law Robert H. Goddard Professor Princeton University Princeton-CEFRC-Combustion Institute Summer School on Combustion June 20-24, 2016 1 What is Combustion? * Study of chemically reacting flows with highly exothermic, temperature-sensitive reactions A Laminar Bunsen Flame A Turbulent Jet Flame Combustion is A Multi-physics & Multi-scale Science * Combustion is a multi- physics science, embodying two major branches of nonlinear science: - Chemical kinetics - Fluid mechanics *

  17. Multidimensional simulation and chemical kinetics development...

    Office of Environmental Management (EM)

    Multidimensional simulation and chemical kinetics development for high efficiency clean combustion engines Multidimensional simulation and chemical kinetics development for high ...

  18. CLEERS Coordination & Joint Development of Benchmark Kinetics...

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

    More Documents & Publications CLEERS Coordination & Joint Development of Benchmark Kinetics for LNT & SCR CLEERS Coordination & Development of Catalyst Process Kinetic...

  19. Chemical kinetics modeling

    SciTech Connect (OSTI)

    Westbrook, C.K.; Pitz, W.J.

    1993-12-01

    This project emphasizes numerical modeling of chemical kinetics of combustion, including applications in both practical combustion systems and in controlled laboratory experiments. Elementary reaction rate parameters are combined into mechanisms which then describe the overall reaction of the fuels being studied. Detailed sensitivity analyses are used to identify those reaction rates and product species distributions to which the results are most sensitive and therefore warrant the greatest attention from other experimental and theoretical research programs. Experimental data from a variety of environments are combined together to validate the reaction mechanisms, including results from laminar flames, shock tubes, flow systems, detonations, and even internal combustion engines.

  20. Kinetics of coal pyrolysis

    SciTech Connect (OSTI)

    Seery, D.J.; Freihaut, J.D.; Proscia, W.M. ); Howard, J.B.; Peters, W.; Hsu, J.; Hajaligol, M.; Sarofim, A. ); Jenkins, R.; Mallin, J.; Espindola-Merin, B. ); Essenhigh, R.; Misra, M.K. )

    1989-07-01

    This report contains results of a coordinated, multi-laboratory investigation of coal devolatilization. Data is reported pertaining to the devolatilization for bituminous coals over three orders of magnitude in apparent heating rate (100 to 100,000 + {degree}C/sec), over two orders of magnitude in particle size (20 to 700 microns), final particle temperatures from 400 to 1600{degree}C, heat transfer modes ranging from convection to radiative, ambient pressure ranging from near vacuum to one atmosphere pressure. The heat transfer characteristics of the reactors are reported in detail. It is assumed the experimental results are to form the basis of a devolatilization data base. Empirical rate expressions are developed for each phase of devolatilization which, when coupled to an awareness of the heat transfer rate potential of a particular devolatilization reactor, indicate the kinetics emphasized by a particular system reactor plus coal sample. The analysis indicates the particular phase of devolatilization that will be emphasized by a particular reactor type and, thereby, the kinetic expressions appropriate to that devolatilization system. Engineering rate expressions are developed from the empirical rate expressions in the context of a fundamental understanding of coal devolatilization developed in the course of the investigation. 164 refs., 223 figs., 44 tabs.

  1. Amber Kinetics | Open Energy Information

    Open Energy Info (EERE)

    search Name: Amber Kinetics Product: Start-up company developing a novel flywheel energy storage system with the Lawrence Livermore National Laboratory. References: Amber...

  2. Updated Eastern Interconnect Wind Power Output and Forecasts for ERGIS: July 2012

    SciTech Connect (OSTI)

    Pennock, K.

    2012-10-01

    AWS Truepower, LLC (AWST) was retained by the National Renewable Energy Laboratory (NREL) to update wind resource, plant output, and wind power forecasts originally produced by the Eastern Wind Integration and Transmission Study (EWITS). The new data set was to incorporate AWST's updated 200-m wind speed map, additional tall towers that were not included in the original study, and new turbine power curves. Additionally, a primary objective of this new study was to employ new data synthesis techniques developed for the PJM Renewable Integration Study (PRIS) to eliminate diurnal discontinuities resulting from the assimilation of observations into mesoscale model runs. The updated data set covers the same geographic area, 10-minute time resolution, and 2004?2006 study period for the same onshore and offshore (Great Lakes and Atlantic coast) sites as the original EWITS data set.

  3. Department of energy oak riDge office

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

    present risk and hinder the Department's missions. 2 DEpaRTMEnT Of EnERgy Oak RiDgE ... Technology Park (ETTP)-evolved and conducted different missions for the Department. ...

  4. Energy Northwest

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

    of interest on, the Series 2015-C Bonds. See "TAX MATTERS" herein. 109,205,000 EnErgy northwEst 44,005,000 Project 1 Electric revenue refunding Bonds, series 2015-C...

  5. ContaCt

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

    Time-dependent experiments have been successfully performed using a broad-spectrum neutron beam. EnErgy-rESoLvEd nEUtron iMaging Tungsten (red) diffused into UO 2 rod. Fuel pellets ...

  6. Energy Storage Research and Development 2008 Progress Report

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

    EnErgy StoragE rESEarch and dEvElopmEnt annual progress report 2008 V e h i c l e T e c h ......... 3 II.A System Development ......

  7. Nonlinear

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

    ... to zonal modes on the damped eigenmode branch. 23 Other channels, e.g., en- ergy ... Controlled Fusion 47, B195 2005. 9 D. R. Baker and M. N. Rosenbluth, Phys. Plasmas 5, ...

  8. CLEERS Coordination & Joint Development of Benchmark Kinetics...

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

    of Catalyst Process Kinetic Data CLEERS Coordination & Joint Development of Benchmark Kinetics for LNT & SCR Functionality of Commercial NOx Storage-Reduction Catalysts...

  9. On the relationships between Michaelis–Menten kinetics, reverse Michaelis–Menten kinetics, Equilibrium Chemistry Approximation kinetics and quadratic kinetics

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Tang, J. Y.

    2015-09-03

    The Michaelis–Menten kinetics and the reverse Michaelis–Menten kinetics are two popular mathematical formulations used in many land biogeochemical models to describe how microbes and plants would respond to changes in substrate abundance. However, the criteria of when to use which of the two are often ambiguous. Here I show that these two kinetics are special approximations to the Equilibrium Chemistry Approximation kinetics, which is the first order approximation to the quadratic kinetics that solves the equation of enzyme-substrate complex exactly for a single enzyme single substrate biogeochemical reaction with the law of mass action and the assumption of quasi-steady-state formore » the enzyme-substrate complex and that the product genesis from enzyme-substrate complex is much slower than the equilibration between enzyme-substrate complexes, substrates and enzymes. In particular, I showed that the derivation of the Michaelis–Menten kinetics does not consider the mass balance constraint of the substrate, and the reverse Michaelis–Menten kinetics does not consider the mass balance constraint of the enzyme, whereas both of these constraints are taken into account in the Equilibrium Chemistry Approximation kinetics. By benchmarking against predictions from the quadratic kinetics for a wide range of substrate and enzyme concentrations, the Michaelis–Menten kinetics was found to persistently under-predict the normalized sensitivity ∂ ln v / ∂ ln k2+ of the reaction velocity v with respect to the maximum product genesis rate k2+, persistently over-predict the normalized sensitivity ∂ ln v / ∂ ln k1+ of v with respect to the intrinsic substrate affinity k1+, persistently over-predict the normalized sensitivity ∂ ln v / ∂ ln [ E ]T of v with respect the total enzyme concentration [ E ]T and persistently under-predict the normalized sensitivity ∂ ln v / ∂ ln [ S ]T of v with respect to the total substrate concentration [ S ]T. Meanwhile, the

  10. Nuclear Reactor Kinetics and Control.

    Energy Science and Technology Software Center (OSTI)

    2009-07-27

    Version 00 Dr. J.D. Lewins has now released the following legacy book for free distribution: Nuclear Reactor Kinetics and Control, Pergamon Press, London, 275 pages, 1978. 1. Introductory Review 2. Neutron and Precursor Equations 3. Elementary Solutions of the Kinetics Equations at Low Power 4. Linear Reactor Process Dynamics with Feedback 5. Power Reactor Control Systems 6. Fluctuations and Reactor Noise 7. Safety and Reliability 8. Non Linear Systems; Stability and Control 9. Analogue Computingmore » Addendum: Jay Basken and Jeffery D. Lewins: Power Series Solution of the Reactor Kinetics Equations, Nuclear Science and Engineering: 122, 407-436 (1996) (authorized for distribution with the book: courtesy of the American Nuclear Society)« less

  11. Stochastic Parallel PARticle Kinetic Simulator

    Energy Science and Technology Software Center (OSTI)

    2008-07-01

    SPPARKS is a kinetic Monte Carlo simulator which implements kinetic and Metropolis Monte Carlo solvers in a general way so that they can be hooked to applications of various kinds. Specific applications are implemented in SPPARKS as physical models which generate events (e.g. a diffusive hop or chemical reaction) and execute them one-by-one. Applications can run in paralle so long as the simulation domain can be partitoned spatially so that multiple events can be invokedmore » simultaneously. SPPARKS is used to model various kinds of mesoscale materials science scenarios such as grain growth, surface deposition and growth, and reaction kinetics. It can also be used to develop new Monte Carlo models that hook to the existing solver and paralle infrastructure provided by the code.« less

  12. Chemical kinetics and combustion modeling

    SciTech Connect (OSTI)

    Miller, J.A.

    1993-12-01

    The goal of this program is to gain qualitative insight into how pollutants are formed in combustion systems and to develop quantitative mathematical models to predict their formation rates. The approach is an integrated one, combining low-pressure flame experiments, chemical kinetics modeling, theory, and kinetics experiments to gain as clear a picture as possible of the process in question. These efforts are focused on problems involved with the nitrogen chemistry of combustion systems and on the formation of soot and PAH in flames.

  13. Kinetics, Mechanics and Microstructure Changes in Storage Media...

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

    Kinetics, Mechanics and Microstructure Changes in Storage Media Kinetics, Mechanics and Microstructure Changes in Storage Media Presentation on the Kinetics, Mechanics and ...

  14. AER NY Kinetics LLC | Open Energy Information

    Open Energy Info (EERE)

    AER NY Kinetics LLC Jump to: navigation, search Name: AER NY Kinetics LLC Address: PO Box 585 21 Entrance Avenue Place: Ogdensburg Zip: 13669 Region: United States Sector: Marine...

  15. On fast reactor kinetics studies

    SciTech Connect (OSTI)

    Seleznev, E. F.; Belov, A. A.; Matveenko, I. P.; Zhukov, A. M.; Raskach, K. F.

    2012-07-01

    The results and the program of fast reactor core time and space kinetics experiments performed and planned to be performed at the IPPE critical facility is presented. The TIMER code was taken as computation support of the experimental work, which allows transient equations to be solved in 3-D geometry with multi-group diffusion approximation. The number of delayed neutron groups varies from 6 to 8. The code implements the solution of both transient neutron transfer problems: a direct one, where neutron flux density and its derivatives, such as reactor power, etc, are determined at each time step, and an inverse one for the point kinetics equation form, where such a parameter as reactivity is determined with a well-known reactor power time variation function. (authors)

  16. Kinetic studies of ICF implosions

    SciTech Connect (OSTI)

    Kagan, Grigory; Herrmann, H. W.; Kim, Y. -H.; Schmitt, M. J.; Hakel, P.; Hsu, S. C.; Hoffman, N. M.; Svyatsky, D.; Baalrud, S. D.; Daligault, J. O.; Sio, H.; Zylstra, A. B.; Rosenberg, M. J.; Rinderknecht, H. G.; Johnson, M. Gatu; Frenje, J. A.; Seguin, F. H.; Li, C. K.; Petrasso, R. D.; Albright, B. J.; Taitano, W.; Kyrala, G. A.; Bradley, P. A.; Huang, C. -K.; McDevitt, C. J.; Chacon, L.; Srinivasan, B.; McEvoy, A. M.; Joshi, T. R.; Adams, C. S.

    2016-01-01

    Here, kinetic effects on inertial confinement fusion have been investigated. In particular, inter-ion-species diffusion and suprathermal ion distribution have been analyzed. The former drives separation of the fuel constituents in the hot reacting core and governs mix at the shell/fuel interface. The latter underlie measurements obtained with nuclear diagnostics, including the fusion yield and inferred ion burn temperatures. Basic mechanisms behind and practical consequences from these effects are discussed.

  17. Multiflow approach to plasma kinetics

    SciTech Connect (OSTI)

    Ignatov, A. M.

    2015-10-15

    Instead of the commonly used Vlasov equation, one is able to treat kinetic phenomena in collisionless plasma with the help of the infinite set of hydrodynamic equations. The present paper deals with the linear approximation of multiflow hydrodynamics. It is shown that single-particle and collective excitations analogous to Van Kampen waves are explicitly separated. Expressions for the energy of all eigenmodes are obtained.

  18. Nonlinear theory of drift-cyclotron kinetics and the possible breakdown of gyro-kinetics

    SciTech Connect (OSTI)

    Waltz, R. E.; Deng Zhao

    2013-01-15

    A nonlinear theory of drift-cyclotron kinetics (termed cyclo-kinetics here) is formulated to test the breakdown of the gyro-kinetic approximations. Six dimensional cyclo-kinetics can be regarded as an extension of five dimensional gyro-kinetics to include high-frequency cyclotron waves, which can interrupt the low-frequency gyro-averaging in the (sixth velocity grid) gyro-phase angle. Nonlinear cyclo-kinetics has no limit on the amplitude of the perturbations. Formally, there is no gyro-averaging when all cyclotron (gyro-phase angle) harmonics of the perturbed distribution function (delta-f) are retained. Retaining only the (low frequency) zeroth cyclotron harmonic in cyclo-kinetics recovers both linear and nonlinear gyro-kinetics. Simple recipes are given for converting continuum nonlinear delta-f gyro-kinetic transport simulation codes to cyclo-kinetics codes by retaining (at least some) higher cyclotron harmonics.

  19. Kinetic Modeling of Microbiological Processes

    SciTech Connect (OSTI)

    Liu, Chongxuan; Fang, Yilin

    2012-09-17

    Kinetic description of microbiological processes is vital for the design and control of microbe-based biotechnologies such as waste water treatment, petroleum oil recovery, and contaminant attenuation and remediation. Various models have been proposed to describe microbiological processes. This editorial article discusses the advantages and limiation of these modeling approaches in cluding tranditional, Monod-type models and derivatives, and recently developed constraint-based approaches. The article also offers the future direction of modeling researches that best suit for petroleum and environmental biotechnologies.

  20. Electron kinetic effects on interferometry,

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

    kinetic effects on interferometry, polarimetry and Thomson scattering measurements in burning plasmas (invited)a) V. V. Mirnov, D. L. Brower, D. J. Den Hartog, W. X. Ding, J. Duff, and E. Parke Citation: Review of Scientific Instruments 85, 11D302 (2014); doi: 10.1063/1.4891176 View online: http://dx.doi.org/10.1063/1.4891176 View Table of Contents: http://scitation.aip.org/content/aip/journal/rsi/85/11?ver=pdfcov Published by the AIP Publishing Articles you may be interested in First

  1. Combustion kinetics and reaction pathways

    SciTech Connect (OSTI)

    Klemm, R.B.; Sutherland, J.W.

    1993-12-01

    This project is focused on the fundamental chemistry of combustion. The overall objectives are to determine rate constants for elementary reactions and to elucidate the pathways of multichannel reactions. A multitechnique approach that features three independent experiments provides unique capabilities in performing reliable kinetic measurements over an exceptionally wide range in temperature, 300 to 2500 K. Recent kinetic work has focused on experimental studies and theoretical calculations of the methane dissociation system (CH{sub 4} + Ar {yields} CH{sub 3} + H + Ar and H + CH{sub 4} {yields} CH{sub 3} + H{sub 2}). Additionally, a discharge flow-photoionization mass spectrometer (DF-PIMS) experiment is used to determine branching fractions for multichannel reactions and to measure ionization thresholds of free radicals. Thus, these photoionization experiments generate data that are relevant to both reaction pathways studies (reaction dynamics) and fundamental thermochemical research. Two distinct advantages of performing PIMS with high intensity, tunable vacuum ultraviolet light at the National Synchrotron Light Source are high detection sensitivity and exceptional selectivity in monitoring radical species.

  2. Kinetic Wave Power | Open Energy Information

    Open Energy Info (EERE)

    Wave Power Jump to: navigation, search Name: Kinetic Wave Power Address: 2861 N Tupelo St Place: Midland Zip: 48642 Region: United States Sector: Marine and Hydrokinetic Phone...

  3. Spectral method for a kinetic swarming model

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Gamba, Irene M.; Haack, Jeffrey R.; Motsch, Sebastien

    2015-04-28

    Here we present the first numerical method for a kinetic description of the Vicsek swarming model. The kinetic model poses a unique challenge, as there is a distribution dependent collision invariant to satisfy when computing the interaction term. We use a spectral representation linked with a discrete constrained optimization to compute these interactions. To test the numerical scheme we investigate the kinetic model at different scales and compare the solution with the microscopic and macroscopic descriptions of the Vicsek model. Lastly, we observe that the kinetic model captures key features such as vortex formation and traveling waves.

  4. Direct Kinetic Measurements of a Criegee Intermediate

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

    Direct Kinetic Measurements of a Criegee Intermediate Print In the earth's troposphere, which blankets the planet surface where we live and breathe, dust particles, gas molecules,...

  5. CLEERS Coordination & Development of Catalyst Process Kinetic...

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

    & Joint Development of Benchmark Kinetics for LNT & SCR Measurement and Characterization of Lean NOx Adsorber Regeneration and Desulfation and Controlling NOx from Multi-mode

  6. Chemical kinetics and oil shale process design

    SciTech Connect (OSTI)

    Burnham, A.K.

    1993-07-01

    Oil shale processes are reviewed with the goal of showing how chemical kinetics influences the design and operation of different processes for different types of oil shale. Reaction kinetics are presented for organic pyrolysis, carbon combustion, carbonate decomposition, and sulfur and nitrogen reactions.

  7. Kinetic advantage of controlled intermediate nuclear fusion

    SciTech Connect (OSTI)

    Guo Xiaoming

    2012-09-26

    The dominated process of controlled fusion is to let nuclei gain enough kinetic energy to overcome Coulomb barrier. As a result, a fusion scheme can consider two factors in its design: to increase kinetic energy of nuclei and to alter the Coulomb barrier. Cold Fusion and Hot fusion are all one-factor schemes while Intermediate Fusion is a twofactors scheme. This made CINF kinetically superior. Cold Fusion reduces deuteron-deuteron distance, addressing Coulomb barrier, and Hot Fusion heat up plasma into extreme high temperature, addressing kinetic energy. Without enough kinetic energy made Cold Fusion skeptical. Extreme high temperature made Hot Fusion very difficult to engineer. Because CIFN addresses both factors, CIFN is a more promising technique to be industrialized.

  8. Modeling of Reactor Kinetics and Dynamics

    SciTech Connect (OSTI)

    Matthew Johnson; Scott Lucas; Pavel Tsvetkov

    2010-09-01

    In order to model a full fuel cycle in a nuclear reactor, it is necessary to simulate the short time-scale kinetic behavior of the reactor as well as the long time-scale dynamics that occur with fuel burnup. The former is modeled using the point kinetics equations, while the latter is modeled by coupling fuel burnup equations with the kinetics equations. When the equations are solved simultaneously with a nonlinear equation solver, the end result is a code with the unique capability of modeling transients at any time during a fuel cycle.

  9. Liquefaction chemistry and kinetics: Hydrogen utilization studies

    SciTech Connect (OSTI)

    Rothenberger, K.S.; Warzinski, R.P.; Cugini, A.V.

    1995-12-31

    The objectives of this project are to investigate the chemistry and kinetics that occur in the initial stages of coal liquefaction and to determine the effects of hydrogen pressure, catalyst activity, and solvent type on the quantity and quality of the products produced. The project comprises three tasks: (1) preconversion chemistry and kinetics, (2) hydrogen utilization studies, and (3) assessment of kinetic models for liquefaction. The hydrogen utilization studies work will be the main topic of this report. However, the other tasks are briefly described.

  10. Large kinetic asymmetry in the metal-insulator transition nucleated...

    Office of Scientific and Technical Information (OSTI)

    Journal Article: Large kinetic asymmetry in the metal-insulator transition nucleated at localized and extended defects Citation Details In-Document Search Title: Large kinetic...

  11. Microfluidics: Kinetics of Hybridized DNA With Fluid Flow Variations...

    Office of Scientific and Technical Information (OSTI)

    Microfluidics: Kinetics of Hybridized DNA With Fluid Flow Variations. Citation Details In-Document Search Title: Microfluidics: Kinetics of Hybridized DNA With Fluid Flow ...

  12. Global kinetics for a commercial diesel oxidation catalyst with...

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

    kinetics for a commercial diesel oxidation catalyst with two exhaust hydrocarbons Global kinetics for a commercial diesel oxidation catalyst with two exhaust hydrocarbons ...

  13. Evaluation of Thermal Evolution Profiles and Estimation of Kinetic...

    Office of Scientific and Technical Information (OSTI)

    of Kinetic Parameters for Pyrolysis of CoalCorn Stover Blends Using Thermogravimetric ... of Kinetic Parameters for Pyrolysis of CoalCorn Stover Blends Using Thermogravimetric ...

  14. Microscale Electrode Design Using Coupled Kinetic, Thermal and...

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

    Microscale Electrode Design Using Coupled Kinetic, Thermal and Mechanical Modeling Microscale Electrode Design Using Coupled Kinetic, Thermal and Mechanical Modeling 2009 DOE ...

  15. Spin-selective recombination kinetics of a model chemical magnetorecep...

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

    Spin-selective recombination kinetics of a model chemical magnetoreceptor Authors: Maeda, ... recombination kinetics of a model chemical magnetoreceptor Source: Chemical ...

  16. Mechanism and Kinetic Modeling of Hydrogenation in The Organic...

    Office of Scientific and Technical Information (OSTI)

    Mechanism and Kinetic Modeling of Hydrogenation in The Organic GetterPd CatalystActivated Carbon Systems Citation Details In-Document Search Title: Mechanism and Kinetic Modeling ...

  17. On the relationships between the Michaelis–Menten kinetics, reverse Michaelis–Menten kinetics, equilibrium chemistry approximation kinetics, and quadratic kinetics

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Tang, J. Y.

    2015-12-01

    The Michaelis–Menten kinetics and the reverse Michaelis–Menten kinetics are two popular mathematical formulations used in many land biogeochemical models to describe how microbes and plants would respond to changes in substrate abundance. However, the criteria of when to use either of the two are often ambiguous. Here I show that these two kinetics are special approximations to the equilibrium chemistry approximation (ECA) kinetics, which is the first-order approximation to the quadratic kinetics that solves the equation of an enzyme–substrate complex exactly for a single-enzyme and single-substrate biogeochemical reaction with the law of mass action and the assumption of a quasi-steadymore » state for the enzyme–substrate complex and that the product genesis from enzyme–substrate complex is much slower than the equilibration between enzyme–substrate complexes, substrates, and enzymes. In particular, I show that the derivation of the Michaelis–Menten kinetics does not consider the mass balance constraint of the substrate, and the reverse Michaelis–Menten kinetics does not consider the mass balance constraint of the enzyme, whereas both of these constraints are taken into account in deriving the equilibrium chemistry approximation kinetics. By benchmarking against predictions from the quadratic kinetics for a wide range of substrate and enzyme concentrations, the Michaelis–Menten kinetics was found to persistently underpredict the normalized sensitivity ∂ ln v / ∂ ln k2+ of the reaction velocity v with respect to the maximum product genesis rate k2+, persistently overpredict the normalized sensitivity ∂ ln v / ∂ ln k1+ of v with respect to the intrinsic substrate affinity k1+, persistently overpredict the normalized sensitivity ∂ ln v / ∂ ln [E]T of v with respect the total enzyme concentration [E]T, and persistently underpredict the normalized sensitivity ∂ ln v / ∂ ln [S]T of v with respect to the total substrate concentration

  18. Kinetics of heavy oil/coal coprocessing

    SciTech Connect (OSTI)

    Szladow, A.J.; Chan, R.K. ); Foudu, S.; Kelly, J.F. )

    1988-06-01

    A number of studies have been reported on coprocessing of coal and oil sand bitumen, petroleum residues and distillate fractions in catalytic and non-catalytic processes. The studies described the effects of feedstock characteristics, process chemistry and operating variables on the product yield and distribution; however, very few kinetic data were reported in these investigations. This paper presents the kinetic data and modelling of the CANMET coal/heavy oil coprocessing process. CANMET has been conducting research and process development work on coprocessing of Canadian heavy oil/bitumen and coal since 1979 including studies of the kinetics and mechanisms of coprocessing. As a continuation of the program, CANMET and Lobbe Technologies undertook a project on mathematical modelling of coprocessing kinetics with emphasis on the development of reaction engineering models for improved process performance and operation.

  19. Direct Kinetic Measurements of a Criegee Intermediate

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

    Direct Kinetic Measurements of a Criegee Intermediate Direct Kinetic Measurements of a Criegee Intermediate Print Wednesday, 25 January 2012 00:00 In the earth's troposphere, which blankets the planet surface where we live and breathe, dust particles, gas molecules, water vapor, and sunlight provide the ingredients for a multitude of chemical reactions that can generate effects ranging from clouds and smog to acid rain and climate change. In 1949, chemist Rudolf Criegee proposed a novel chemical

  20. Mechanisms and kinetics of coal hydrogenation

    SciTech Connect (OSTI)

    Baldwin, R M; Furlong, M W

    1981-05-01

    Colorado School of Mines is engaged in an experimental program to develop comprehensive models for the effects of coal composition upon the kinetics and mechanisms of coal hydrogenation, for the effects of mineral matter additives (disposable catalysts) upon kinetics and mechanisms of coal hydrogenation, and for the kinetics and mechanisms of the hydrogenation of coal derived products such as preasphaltenes, and asphaltenes. Experimental work was completed on a suite of bituminous coals, thus completing the initial phase of the coal reactivity study. Eleven of the 14 coals of the suite were successfully run in duplicate. Conversion to THF solubles was correlated well by pseudo-second order kinetics. The resulting kinetic rate constants correlated with H/C ratio, mean-max vitrinite reflectance, and a specially-defined fraction of reactive macerals. The data did not correlate well with O/C ratios of the parent coals. Computer-derived statistical fits of various kinetic models were limited in their effectiveness at fitting the experimental data. Experimental work on the first phase of the disposal catalyst studies was completed. Statistical significance testing of the experimental data showed: fractional conversion and yield of light hydrocarbon products increased with time; and mineral properties of the additives were more significant in increasing overall conversion than the additive surface areas. The relative effects of the additives are given.

  1. Diffusion In Confinement: Kinetic Simulations of Self- andCollective...

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

    Diffusion In Confinement: Kinetic Simulations of Self- and Collective-Diffusion Behavior of Adsorbed Gases...

  2. Chemical Kinetic Modeling of Advanced Transportation Fuels

    SciTech Connect (OSTI)

    PItz, W J; Westbrook, C K; Herbinet, O

    2009-01-20

    Development of detailed chemical kinetic models for advanced petroleum-based and nonpetroleum based fuels is a difficult challenge because of the hundreds to thousands of different components in these fuels and because some of these fuels contain components that have not been considered in the past. It is important to develop detailed chemical kinetic models for these fuels since the models can be put into engine simulation codes used for optimizing engine design for maximum efficiency and minimal pollutant emissions. For example, these chemistry-enabled engine codes can be used to optimize combustion chamber shape and fuel injection timing. They also allow insight into how the composition of advanced petroleum-based and non-petroleum based fuels affect engine performance characteristics. Additionally, chemical kinetic models can be used separately to interpret important in-cylinder experimental data and gain insight into advanced engine combustion processes such as HCCI and lean burn engines. The objectives are: (1) Develop detailed chemical kinetic reaction models for components of advanced petroleum-based and non-petroleum based fuels. These fuels models include components from vegetable-oil-derived biodiesel, oil-sand derived fuel, alcohol fuels and other advanced bio-based and alternative fuels. (2) Develop detailed chemical kinetic reaction models for mixtures of non-petroleum and petroleum-based components to represent real fuels and lead to efficient reduced combustion models needed for engine modeling codes. (3) Characterize the role of fuel composition on efficiency and pollutant emissions from practical automotive engines.

  3. Viral kinetic modeling: state of the art

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Canini, Laetitia; Perelson, Alan S.

    2014-06-25

    Viral kinetic modeling has led to increased understanding of the within host dynamics of viral infections and the effects of therapy. Here we review recent developments in the modeling of viral infection kinetics with emphasis on two infectious diseases: hepatitis C and influenza. We review how viral kinetic modeling has evolved from simple models of viral infections treated with a drug or drug cocktail with an assumed constant effectiveness to models that incorporate drug pharmacokinetics and pharmacodynamics, as well as phenomenological models that simply assume drugs have time varying-effectiveness. We also discuss multiscale models that include intracellular events in viralmore » replication, models of drug-resistance, models that include innate and adaptive immune responses and models that incorporate cell-to-cell spread of infection. Overall, viral kinetic modeling has provided new insights into the understanding of the disease progression and the modes of action of several drugs. In conclusion, we expect that viral kinetic modeling will be increasingly used in the coming years to optimize drug regimens in order to improve therapeutic outcomes and treatment tolerability for infectious diseases.« less

  4. Neptunium Binding Kinetics with Arsenazo(III)

    SciTech Connect (OSTI)

    Leigh R. Martin; Aaron T. Johnson; Stephen P. Mezyk

    2014-08-01

    This document has been prepared to meet FCR&D level 2 milestone M2FT-14IN0304021, Report on the results of actinide binding kinetics with aqueous phase complexants This work was carried out under the auspices of the Thermodynamics and Kinetics of Advanced Separations Systems FCR&D work package. The report details kinetics experiments that were performed to measure rates of aqueous phase complexation for pentavalent neptunium with the chromotropic dye Arsenazo III (AAIII). The studies performed were designed to determine how pH, ionic strength and AAIII concentration may affect the rate of the reaction. A brief comparison with hexavalent neptunium is also made. It was identified that as pH was increased the rate of reaction also increased, however increasing the ionic strength and concentration of AAIII had the opposite effect. Interestingly, the rate of reaction of Np(VI) with AAIII was found to be slower than that of the Np(V) reaction.

  5. Kinetic studies of elementary chemical reactions

    SciTech Connect (OSTI)

    Durant, J.L. Jr.

    1993-12-01

    This program concerning kinetic studies of elementary chemical reactions is presently focussed on understanding reactions of NH{sub x} species. To reach this goal, the author is pursuing experimental studies of reaction rate coefficients and product branching fractions as well as using electronic structure calculations to calculate transition state properties and reaction rate calculations to relate these properties to predicted kinetic behavior. The synergy existing between the experimental and theoretical studies allow one to gain a deeper insight into more complex elementary reactions.

  6. Kinetics of heavy oil/coal coprocessing

    SciTech Connect (OSTI)

    Szladow, A.J.; Chan, R.K.; Fouda, S.; Kelly, J.F. )

    1988-01-01

    A number of studies have been reported on coprocessing of coal and oil sand bitumen, petroleum residues and distillate fractions in catalytic and non-catalytic processes. The studies described the effects of feedstock characteristics, process chemistry and operating variables on the product yield and distribution; however, very few kinetic data were reported in these investigations. This paper presents the kinetic data and modeling of the CANMET coal/heavy oil coprocessing process. A number of reaction networks were evaluated for CANMET coprocessing. The final choice of model was a parallel model with some sequential characteristics. The model explained 90.0 percent of the total variance, which was considered satisfactory in view of the difficulties of modeling preasphaltenes. The models which were evaluated showed that the kinetic approach successfully applied to coal liquefaction and heavy oil upgrading can be also applied to coprocessing. The coal conversion networks and heavy oil upgrading networks are interrelated via the forward reaction paths of preasphaltenes, asphaltenes, and THFI and via the reverse kinetic paths of an adduct formation between preasphaltenes and heavy oil.

  7. Direct Kinetic Measurements of a Criegee Intermediate

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

    J.D. Savee, D.L. Osborn, S.S. Vasu, C.J. Percival, D.E. Shallcross, and C.A. Taatjes, "Direct Kinetic Measurements of Criegee Intermediate (CH2OO) Formed by Reaction of CH2I...

  8. From kinetic MHD in stellarators to a fully kinetic description of wave particle interaction

    SciTech Connect (OSTI)

    Koenies, Axel; Mishchenko, Alexey; Hatzky, Roman

    2008-11-01

    We use a linearized model of kinetic MHD for the perturbative calculation of growth rates of Alfven eigenmodes.The numerical model, a code called CAS3D-K, is based on the three-dimensional ideal MHD stability code CAS3D and a numeric solution of the drift kinetic equation which avoids approximations to the magnetic geometry but neglects the drifts of the particles away from the flux surface.The approach is used to discuss stability boundaries in W7-X and W7-AS and considers both, passing and reflected particles. The limits of the applicability of the model will be discussed as well.It will be shown that gyro-kinetic PIC codes offer a very promising way to improve the model. The two-dimensional linear PIC code GYGLES is used to calculate gyro-kinetic counterparts of ideal MHD modes in cylindrical and in tokamak geometry.

  9. Reflected kinetics model for nuclear space reactor kinetics and control scoping calculations

    SciTech Connect (OSTI)

    Washington, K.E.

    1986-05-01

    The objective of this research is to develop a model that offers an alternative to the point kinetics (PK) modelling approach in the analysis of space reactor kinetics and control studies. Modelling effort will focus on the explicit treatment of control drums as reactivity input devices so that the transition to automatic control can be smoothly done. The proposed model is developed for the specific integration of automatic control and the solution of the servo mechanism problem. The integration of the kinetics model with an automatic controller will provide a useful tool for performing space reactor scoping studies for different designs and configurations. Such a tool should prove to be invaluable in the design phase of a space nuclear system from the point of view of kinetics and control limitations.

  10. The LANL atomic kinetics modeling effort and its application...

    Office of Scientific and Technical Information (OSTI)

    An on-line version of the codes is available at http:aphysics2.lanl.govtempweb. ATOMIC kinetics modelling code uses the atomic data for LTE or NLTE population kinetics models ...

  11. Investigation of NO2 Oxidation Kinetics and Burning Mode for...

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

    NO2 Oxidation Kinetics and Burning Mode for Medium Duty Diesel Particulate: Contrasting O2 and NO2 Oxidation Investigation of NO2 Oxidation Kinetics and Burning Mode for Medium ...

  12. Chemical Kinetics Research on HCCI and Diesel Fuels

    Broader source: Energy.gov [DOE]

    Discusses detailed chemical kinetics mechanisms for complex hydrocarbon fuels and computationally efficiecnt, accurate methodologies for modeling advanced combustion strategies.

  13. Laboratory support for in situ gasification reaction kinetics...

    Office of Scientific and Technical Information (OSTI)

    CARBONACEOUS MATERIALS; CHALCOGENIDES; DECOMPOSITION; ENERGY SOURCES; FOSSIL FUELS; FUELS; IN-SITU PROCESSING; KINETICS; OXIDES; OXYGEN COMPOUNDS; PROCESSING; REACTION ...

  14. Laboratory support for in situ gasification reaction kinetics...

    Office of Scientific and Technical Information (OSTI)

    COMPOUNDS; CARBONACEOUS MATERIALS; CHALCOGENIDES; DECOMPOSITION; ENERGY SOURCES; FOSSIL FUELS; FUELS; IN-SITU PROCESSING; KINETICS; OXIDES; OXYGEN COMPOUNDS; PROCESSING; REACTION ...

  15. Multidimensional simulation and chemical kinetics development for high

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

    efficiency clean combustion engines | Department of Energy Multidimensional simulation and chemical kinetics development for high efficiency clean combustion engines Multidimensional simulation and chemical kinetics development for high efficiency clean combustion engines Developing chemical kinetic mechanisms and applying them to simulating engine combustion processes. deer09_aceves.pdf (3.04 MB) More Documents & Publications Chemical Kinetic Research on HCCI & Diesel Fuels Chemical

  16. Direct Kinetic Measurements of a Criegee Intermediate

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

    Direct Kinetic Measurements of a Criegee Intermediate Print In the earth's troposphere, which blankets the planet surface where we live and breathe, dust particles, gas molecules, water vapor, and sunlight provide the ingredients for a multitude of chemical reactions that can generate effects ranging from clouds and smog to acid rain and climate change. In 1949, chemist Rudolf Criegee proposed a novel chemical pathway for one such reaction, known as ozonolysis: the destruction of alkenes (a type

  17. Direct Kinetic Measurements of a Criegee Intermediate

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

    Direct Kinetic Measurements of a Criegee Intermediate Print In the earth's troposphere, which blankets the planet surface where we live and breathe, dust particles, gas molecules, water vapor, and sunlight provide the ingredients for a multitude of chemical reactions that can generate effects ranging from clouds and smog to acid rain and climate change. In 1949, chemist Rudolf Criegee proposed a novel chemical pathway for one such reaction, known as ozonolysis: the destruction of alkenes (a type

  18. Direct Kinetic Measurements of a Criegee Intermediate

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

    Direct Kinetic Measurements of a Criegee Intermediate Print In the earth's troposphere, which blankets the planet surface where we live and breathe, dust particles, gas molecules, water vapor, and sunlight provide the ingredients for a multitude of chemical reactions that can generate effects ranging from clouds and smog to acid rain and climate change. In 1949, chemist Rudolf Criegee proposed a novel chemical pathway for one such reaction, known as ozonolysis: the destruction of alkenes (a type

  19. Direct Kinetic Measurements of a Criegee Intermediate

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

    Direct Kinetic Measurements of a Criegee Intermediate Print In the earth's troposphere, which blankets the planet surface where we live and breathe, dust particles, gas molecules, water vapor, and sunlight provide the ingredients for a multitude of chemical reactions that can generate effects ranging from clouds and smog to acid rain and climate change. In 1949, chemist Rudolf Criegee proposed a novel chemical pathway for one such reaction, known as ozonolysis: the destruction of alkenes (a type

  20. Direct Kinetic Measurements of a Criegee Intermediate

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

    Direct Kinetic Measurements of a Criegee Intermediate Print In the earth's troposphere, which blankets the planet surface where we live and breathe, dust particles, gas molecules, water vapor, and sunlight provide the ingredients for a multitude of chemical reactions that can generate effects ranging from clouds and smog to acid rain and climate change. In 1949, chemist Rudolf Criegee proposed a novel chemical pathway for one such reaction, known as ozonolysis: the destruction of alkenes (a type

  1. Direct Kinetic Measurements of a Criegee Intermediate

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

    Direct Kinetic Measurements of a Criegee Intermediate Print In the earth's troposphere, which blankets the planet surface where we live and breathe, dust particles, gas molecules, water vapor, and sunlight provide the ingredients for a multitude of chemical reactions that can generate effects ranging from clouds and smog to acid rain and climate change. In 1949, chemist Rudolf Criegee proposed a novel chemical pathway for one such reaction, known as ozonolysis: the destruction of alkenes (a type

  2. Direct Kinetic Measurements of a Criegee Intermediate

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

    Direct Kinetic Measurements of a Criegee Intermediate Print In the earth's troposphere, which blankets the planet surface where we live and breathe, dust particles, gas molecules, water vapor, and sunlight provide the ingredients for a multitude of chemical reactions that can generate effects ranging from clouds and smog to acid rain and climate change. In 1949, chemist Rudolf Criegee proposed a novel chemical pathway for one such reaction, known as ozonolysis: the destruction of alkenes (a type

  3. Detailed Chemical Kinetic Modeling of Cyclohexane Oxidation

    SciTech Connect (OSTI)

    Silke, E J; Pitz, W J; Westbrook, C K; Ribaucour, M

    2006-11-10

    A detailed chemical kinetic mechanism has been developed and used to study the oxidation of cyclohexane at both low and high temperatures. Reaction rate constant rules are developed for the low temperature combustion of cyclohexane. These rules can be used for in chemical kinetic mechanisms for other cycloalkanes. Since cyclohexane produces only one type of cyclohexyl radical, much of the low temperature chemistry of cyclohexane is described in terms of one potential energy diagram showing the reaction of cyclohexyl radical + O{sub 2} through five, six and seven membered ring transition states. The direct elimination of cyclohexene and HO{sub 2} from RO{sub 2} is included in the treatment using a modified rate constant of Cavallotti et al. Published and unpublished data from the Lille rapid compression machine, as well as jet-stirred reactor data are used to validate the mechanism. The effect of heat loss is included in the simulations, an improvement on previous studies on cyclohexane. Calculations indicated that the production of 1,2-epoxycyclohexane observed in the experiments can not be simulated based on the current understanding of low temperature chemistry. Possible 'alternative' H-atom isomerizations leading to different products from the parent O{sub 2}QOOH radical were included in the low temperature chemical kinetic mechanism and were found to play a significant role.

  4. Kinetics of coal combustion: Part 2, Mechanisms and kinetics of coal volatiles combustion

    SciTech Connect (OSTI)

    Essenhigh, R.H.; Bailey, E.G.; Shaw, D.W. )

    1988-12-01

    Values of global kinetic constants for the combustion of coal volatiles have been determined for the first time for volatiles from three coals (two bituminous coals and a Texas lignite). Global kinetic constants for methane and propane were also measured in the same apparatus to allow comparison with reference gases. Comparisons have also been made with values of global kinetics for pure hydrocarbons from a range of experiments as found in the literature. The volatiles were pyrolyzed from crushed coal drawn on weighed trays through a gas-fired muffle furnace, and they were burned at the top of a tube in an intense back-mix volume treated theoretically as a stirred reactor. Two types of experiment were carried out: partial combustion measurements near the stoichiometric for all coals from which the global kinetics were determined; and extinction limits for the Pittsburgh {number sign}8 coal volatiles to determine the extinction loop. The near stoichiometric generated kinetic data were used to predict the extinction limits with substantial agreement. Extinction loops for methane, propane and carbon monoxide were also measured for comparison.

  5. Kinetic evidence for protein clustering at a surface

    SciTech Connect (OSTI)

    Ramsden, J.J. ); Bachmanova, G.I.; Archakov, A.I. )

    1994-12-01

    The molecules designated 1A2 and 2B4 belong to the cytochrome P450 protein superfamily. They can interact specifically with lipid bilayers via the penetration of part of their amino acid chains into the bilayer. The kinetics of their irreversible adsorption from solution to phospholipid bilayers, accurately measured in the low to intermediate coverage range using an integrated optics reflectance technique, differ significantly: at intermediate bulk solution concentrations, 2B4 shows typical random sequential adsorption (RSA) kinetics, whereas 1A2 shows Langmuir kinetics. At higher bulk concentration the behavior of 1[ital A]2 switches to RSA kinetics, and at very low concentrations 2[ital B]4 switches to Langmuir kinetics. The Langmuir kinetics provides strong evidence for clustering of the molecules at the bilayer surface, and the observed concentration dependence of the kinetics is consistent with the clusters arising through lateral diffusion of the proteins on the surface.

  6. Vlasov simulations of kinetic Alfvén waves at proton kinetic scales

    SciTech Connect (OSTI)

    Vásconez, C. L.; Valentini, F.; Veltri, P.; Camporeale, E.

    2014-11-15

    Kinetic Alfvén waves represent an important subject in space plasma physics, since they are thought to play a crucial role in the development of the turbulent energy cascade in the solar wind plasma at short wavelengths (of the order of the proton gyro radius ρ{sub p} and/or inertial length d{sub p} and beyond). A full understanding of the physical mechanisms which govern the kinetic plasma dynamics at these scales can provide important clues on the problem of the turbulent dissipation and heating in collisionless systems. In this paper, hybrid Vlasov-Maxwell simulations are employed to analyze in detail the features of the kinetic Alfvén waves at proton kinetic scales, in typical conditions of the solar wind environment (proton plasma beta β{sub p} = 1). In particular, linear and nonlinear regimes of propagation of these fluctuations have been investigated in a single-wave situation, focusing on the physical processes of collisionless Landau damping and wave-particle resonant interaction. Interestingly, since for wavelengths close to d{sub p} and β{sub p} ≃ 1 (for which ρ{sub p} ≃ d{sub p}) the kinetic Alfvén waves have small phase speed compared to the proton thermal velocity, wave-particle interaction processes produce significant deformations in the core of the particle velocity distribution, appearing as phase space vortices and resulting in flat-top velocity profiles. Moreover, as the Eulerian hybrid Vlasov-Maxwell algorithm allows for a clean almost noise-free description of the velocity space, three-dimensional plots of the proton velocity distribution help to emphasize how the plasma departs from the Maxwellian configuration of thermodynamic equilibrium due to nonlinear kinetic effects.

  7. Pedestal Fueling Simulations with a Coupled Kinetic-kinetic Plasma-neutral Transport Code

    SciTech Connect (OSTI)

    D.P. Stotler, C.S. Chang, S.H. Ku, J. Lang and G.Y. Park

    2012-08-29

    A Monte Carlo neutral transport routine, based on DEGAS2, has been coupled to the guiding center ion-electron-neutral neoclassical PIC code XGC0 to provide a realistic treatment of neutral atoms and molecules in the tokamak edge plasma. The DEGAS2 routine allows detailed atomic physics and plasma-material interaction processes to be incorporated into these simulations. The spatial pro le of the neutral particle source used in the DEGAS2 routine is determined from the uxes of XGC0 ions to the material surfaces. The kinetic-kinetic plasma-neutral transport capability is demonstrated with example pedestal fueling simulations.

  8. Energy Conservation Tests of a Coupled Kinetic-kinetic Plasma-neutral Transport Code

    SciTech Connect (OSTI)

    Stotler, D. P.; Chang, C. S.; Ku, S. H.; Lang, J.; Park, G.

    2012-08-29

    A Monte Carlo neutral transport routine, based on DEGAS2, has been coupled to the guiding center ion-electron-neutral neoclassical PIC code XGC0 to provide a realistic treatment of neutral atoms and molecules in the tokamak edge plasma. The DEGAS2 routine allows detailed atomic physics and plasma-material interaction processes to be incorporated into these simulations. The spatial pro le of the neutral particle source used in the DEGAS2 routine is determined from the uxes of XGC0 ions to the material surfaces. The kinetic-kinetic plasma-neutral transport capability is demonstrated with example pedestal fueling simulations.

  9. Pyrolysis kinetics for the Bakken shale

    SciTech Connect (OSTI)

    Burnham, A.K.

    1992-01-01

    Pyrolysis kinetics are reported and compared for rapid open pyrolysis experiments: Py-TG-FTIR, Py-FID, and Py-MS. Where the type of information obtained overlapped, the results were very similar. The principal activation energy for total hydrocarbon generation using a parallel reaction model is 52 kcal/mol. As with most petroleum source rocks, carbon dioxide generation tends to lead oil formation while ethene and methane generation tend to lag oil generation. The midpoint of oil generation for a geological heating rate of 3 {degrees}C/m.y. is predicted to be between 130 and 140{degrees}C. 5 refs., 4 figs., 1 tab.

  10. Studies of combustion kinetics and mechanisms

    SciTech Connect (OSTI)

    Gutman, D.

    1993-12-01

    The objective of the current research is to gain new quantitative knowledge of the kinetics and mechanisms of polyatomic free radicals which are important in hydrocarbon combustion processes. The special facility designed and built for these (which includes a heatable tubular reactor coupled to a photoionization mass spectrometer) is continually being improved. Where possible, these experimental studies are coupled with theoretical ones, sometimes conducted in collaboration with others, to obtain an improved understanding of the factors determining reactivity. The decomposition of acetyl radicals, isopropyl radicals, and n-propyl radicals have been studied as well as the oxidation of methylpropargyl radicals.

  11. The Hydriding Kinetics of Organic Hydrogen Getters

    SciTech Connect (OSTI)

    Powell, G. L.

    2002-02-11

    The aging of hermetically sealed systems is often accompanied by the gradual production of hydrogen gas that is a result of the decay of environmental gases and the degradation of organic materials. In particular, the oxygen, water, hydrogen ''equilibrium'' is affected by the removal of oxygen due the oxidation of metals and organic materials. This shift of the above ''equilibrium'' towards the formation of hydrogen gas, particularly in crevices, may eventually reach an explosive level of hydrogen gas or degrade metals by hydriding them. The latter process is generally delayed until the oxidizing species are significantly reduced. Organic hydrogen getters introduced by Allied Signal Aerospace Company, Kansas City Division have proven to be a very effective means of preventing hydrogen gas accumulation in sealed containers. These getters are relatively unaffected by air and environmental gases. They can be packaged in a variety of ways to fit particular needs such as porous pellets, fine or coarse [gravel] powder, or loaded into silicone rubber. The hydrogen gettering reactions are extremely irreversible since the hydrogen gas is converted into an organic hydrocarbon. These getters are based on the palladium-catalyzed hydrogenation of triple bonds to double and then single bonds in aromatic aryl compounds. DEB (1,4 bis (phenyl ethynyl) benzene) typically mixed with 25% by weight carbon with palladium (1% by weight of carbon) is one of the newest and best of these organic hydrogen getters. The reaction mechanisms are complex involving solid state reaction with a heterogeneous catalyst leading to the many intermediates, including mixed alkyl and aryl hydrocarbons with the possibilities of many isomers. The reaction kinetics mechanisms are also strongly influenced by the form in which they are packaged. For example, the hydriding rates for pellets and gravel have a strong dependence on reaction extent (i.e., DEB reduction) and a kinetic order in pressure of 0

  12. Kinetics of iodine hydrolysis in unbuffered solutions

    SciTech Connect (OSTI)

    Palmer, D.A.; Lyons, L.J.

    1988-01-01

    The kinetics of hydrolysis or disproportionation of hypoiodite were studied spectrophotometrically in basic solution at an ionic strength of 0.2 M as a function of pH, iodide and total iodine concentration, and temperature. The existence of three independent pathways for this second-order process was confirmed. The pH-stat method was used to monitor the corresponding reaction of hypoiodous acid in weakly alkaline solution. The generalized rate law for the disproportionation is: /minus/d((HOI) + (OI/sup /minus//))dt = k /sub a/(HOI)/sup 2/ + k/sub b/(HOI) (OI/sup /minus//) + k/sub c/(OI/sup /minus//)/sup 2/ + k/sub d/(I/sub 2/OH/sup /minus//) (OI/sup /minus//). The values of k/sub a/ and k/sub b/ are substantially smaller than previously reported. However, an unexplained contribution to the rate law resulting from the pH-stat measurements was also obtained. The rapid recombination of iodide and iodate in HClO/sub 4/ solutions was followed by stopped-flow spectrophotometry at three ionic strengths, and over a range of iodide and hydrogen ion concentrations, and at eight temperatures. Fifth-order kinetics were observed with no detectable induction period. 14 refs., 4 figs., 1 tab.

  13. PBXN-9 Ignition Kinetics and Deflagration Rates

    SciTech Connect (OSTI)

    Glascoe, E; Maienschein, J; Burnham, A; Koerner, J; Hsu, P; Wemhoff, A

    2008-04-24

    The ignition kinetics and deflagration rates of PBXN-9 were measured using specially designed instruments at LLNL and compared with previous work on similar HMX based materials. Ignition kinetics were measured based on the One Dimensional Time-to-Explosion combined with ALE3D modeling. Results of these experiments indicate that PBXN-9 behaves much like other HMX based materials (i.e. LX-04, LX-07, LX-10 and PBX-9501) and the dominant factor in these experiments is the type of explosive, not the type of binder/plasticizer. In contrast, the deflagration behavior of PBXN-9 is quite different from similar high weight percent HMX based materials (i.e LX-10, LX-07 and PBX-9501). PBXN-9 burns in a laminar manner over the full pressure range studied (0-310 MPa) unlike LX-10, LX-07, and PBX-9501. The difference in deflagration behavior is attributed to the nature of the binder/plasticizer alone or in conjunction with the volume of binder present in PBXN-9.

  14. Kinetics, Mechanics and Microstructure Changes in Storage Media |

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

    Department of Energy Kinetics, Mechanics and Microstructure Changes in Storage Media Kinetics, Mechanics and Microstructure Changes in Storage Media Presentation on the Kinetics, Mechanics and Microstructure Changes in Storage Media given at the DOE Theory Focus Session on Hydrogen Storage Materials on May 18, 2006. storage_theory_session_eiazab.pdf (1.21 MB) More Documents & Publications Summary Report from Theory Focus Session on Hydrogen Storage Materials Documentation of Hybrid

  15. Confined martensitic phase transformation kinetics and lattice dynamics in

    Office of Scientific and Technical Information (OSTI)

    Ni-Co-Fe-Ga shape memory alloys (Journal Article) | SciTech Connect Confined martensitic phase transformation kinetics and lattice dynamics in Ni-Co-Fe-Ga shape memory alloys Citation Details In-Document Search Title: Confined martensitic phase transformation kinetics and lattice dynamics in Ni-Co-Fe-Ga shape memory alloys Here we describe insights into the phase transformation kinetics and lattice dynamics associated with the newly discovered confined martensitic transformation, which are

  16. Uranium and Strontium Batch Sorption and Diffusion Kinetics into...

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

    Uranium and Strontium Batch Sorption and Diffusion Kinetics into Mesoporous Silica Friday, ... and fate of radioactive material such as uranium (U) and strontium (Sr) in the environment ...

  17. Multiscale Mathematics For Plasma Kinetics Spanning Multiple Collisionality Regimes

    SciTech Connect (OSTI)

    Caflisch, Russel E.

    2015-02-17

    This is the Final Technical Report on this grant. The subject of this grant is accelerated simulation for plasma kinetics, in particular for Coulomb collisions in a plasma.

  18. Desorption Kinetics of Methanol, Ethanol, and Water from Graphene...

    Office of Scientific and Technical Information (OSTI)

    desorption kinetics would be readily apparent in the experimental TPD spectra. Authors: Smith, R. Scott ; Matthiesen, Jesper ; Kay, Bruce D. Publication Date: 2014-09-18 OSTI...

  19. Micro Hydro Kinetic Turbines from Smart Hydro Power | Open Energy...

    Open Energy Info (EERE)

    Hydro Kinetic Turbines from Smart Hydro Power Jump to: navigation, search << Return to the MHK database homepage Tauchturbine.jpg Technology Profile Project(s) where this...

  20. Ultrafast kinetics subsequent to shock compression in an oxygen...

    Office of Scientific and Technical Information (OSTI)

    to shock compression in an oxygen-balanced mixture of nitromethane and hydrogen peroxide Citation Details In-Document Search Title: Ultrafast kinetics subsequent to shock ...

  1. Ultrafast kinetics subsequent to shock in an unreacted, oxygen...

    Office of Scientific and Technical Information (OSTI)

    shock in an unreacted, oxygen balanced mixture of nitromethane and hydrogen peroxide Citation Details In-Document Search Title: Ultrafast kinetics subsequent to shock in an ...

  2. Coupled Kinetic, Thermal, and Mechanical Modeling of FIB Micro...

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

    Kinetics and Ion Mobility in Electrode Materials for Advanced Lithium Ion Batteries Materials Characterization Capabilities at the High Temperature Materials Laboratory and...

  3. Kinetics of the Hydrogen Atom Abstraction Reactions from 1-Butanol...

    Office of Scientific and Technical Information (OSTI)

    Theory Matches Experiment and More Citation Details In-Document Search Title: Kinetics of the Hydrogen Atom Abstraction Reactions from 1-Butanol by Hydroxyl Radical: Theory ...

  4. Transport Phenomena and Interfacial Kinetics in Planar Microfluidic

    Office of Scientific and Technical Information (OSTI)

    Transport Phenomena and Interfacial Kinetics in Planar Microfluidic Membraneless Fuel Cells Abruna, Hector Daniel Cornell University 30 DIRECT ENERGY CONVERSION Our work is...

  5. A Comparison of HCCI Engine Performance Data and Kinetic Modeling...

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

    Kinetic models of fuels are needed to allow the simulation of engine performance for research, design, or verification purposes. PDF icon deer09bunting.pdf More Documents &...

  6. MHK Projects/Ogdensburg Kinetic Energy Project | Open Energy...

    Open Energy Info (EERE)

    Project Phase Phase 1 Main Overseeing Organization AER NY Kinetics LLC Project Licensing Environmental Monitoring and Mitigation Efforts See Tethys << Return to the MHK database...

  7. Vehicle Technologies Office Merit Review 2016: Chemical Kinetic...

    Office of Environmental Management (EM)

    Vehicle Technologies Office Merit Review 2016: Chemical Kinetic Models for Advanced Engine Combustion Presentation given by Lawrence Livermore National Laboratory (LLNL) at the ...

  8. Transport Phenomena and Interfacial Kinetics in Planar Microfluidic...

    Office of Scientific and Technical Information (OSTI)

    Technical Report: Transport Phenomena and Interfacial Kinetics in Planar Microfluidic Membraneless Fuel Cells Citation Details In-Document Search Title: Transport Phenomena and ...

  9. Diffusion in confinement: kinetic simulations of self- and collective...

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

    confinement: kinetic simulations of self- and collective diffusion behavior of adsorbed gases Previous Next List M. K. F. Abouelnasr and B. Smit, PCCP 14 (33), 11600 (2012) DOI:...

  10. Simulations of Kinetic Events at the Atomic Scale

    Broader source: Energy.gov [DOE]

    Presentation on the Simulations of Kinetic Events at the Atomic Scale given at the DOE Theory Focus Session on Hydrogen Storage Materials on May 18, 2006.

  11. Microscale Electrode Design Using Coupled Kinetic, Thermal and...

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

    Documents & Publications track 3: enhanced geothermal systems (EGS) | geothermal 2015 peer review Coupled Kinetic, Thermal, and Mechanical Modeling of FIB Micro-machined...

  12. Pressure Dependent Decomposition Kinetics of the Energetic Material...

    Office of Scientific and Technical Information (OSTI)

    Sponsoring Org: USDOE Country of Publication: United States Language: English Subject: 37 INORGANIC, ORGANIC, PHYSICAL AND ANALYTICAL CHEMISTRY; ACCELERATION; DIAMONDS; KINETICS;...

  13. Incorporation of aqueous reaction and sorption kinetics andbiodegradat...

    Office of Scientific and Technical Information (OSTI)

    A 1-D reactive transport problem with kinetic biodegradation and sorption was investigated, which models the processes when a pulse of water containing NTA (nitrylotriacetate) and ...

  14. Kinetic performance of CO2 absorption into a potassium carbonate...

    Office of Scientific and Technical Information (OSTI)

    Title: Kinetic performance of CO2 absorption into a potassium carbonate solution ... Type: Publisher's Accepted Manuscript Journal Name: Chemical Engineering Journal (Print) ...

  15. Brittle failure kinetics model for concrete

    SciTech Connect (OSTI)

    Silling, S.A.

    1997-03-01

    A new constitutive model is proposed for the modeling of penetration and large stress waves in concrete. Rate effects are incorporated explicitly into the damage evolution law, hence the term brittle failure kinetics. The damage variable parameterizes a family of Mohr-Coulomb strength curves. The model, which has been implemented in the CTH code, has been shown to reproduce some distinctive phenomena that occur in penetration of concrete targets. Among these are the sharp spike in deceleration of a rigid penetrator immediately after impact. Another is the size scale effect, which leads to a nonlinear scaling of penetration depth with penetrator size. This paper discusses the theory of the model and some results of an extensive validation effort.

  16. Detailed Kinetic Modeling of Gasoline Surrogate Mixtures

    SciTech Connect (OSTI)

    Mehl, M; Curran, H J; Pitz, W J; Westbrook, C K

    2009-03-09

    Real fuels are complex mixtures of thousands of hydrocarbon compounds including linear and branched paraffins, naphthenes, olefins and aromatics. It is generally agreed that their behavior can be effectively reproduced by simpler fuel surrogates containing a limited number of components. In this work, a recently revised version of the kinetic model by the authors is used to analyze the combustion behavior of several components relevant to gasoline surrogate formulation. Particular attention is devoted to linear and branched saturated hydrocarbons (PRF mixtures), olefins (1-hexene) and aromatics (toluene). Model predictions for pure components, binary mixtures and multi-component gasoline surrogates are compared with recent experimental information collected in rapid compression machine, shock tube and jet stirred reactors covering a wide range of conditions pertinent to internal combustion engines. Simulation results are discussed focusing attention on the mixing effects of the fuel components.

  17. Spectroscopy, Kinetics, and Dynamics of Combustion Radicals

    SciTech Connect (OSTI)

    Nesbitt, David J.

    2013-08-06

    Spectroscopy, kinetics and dynamics of jet cooled hydrocarbon transients relevant to the DOE combustion mission have been explored, exploiting i) high resolution IR lasers, ii) slit discharge sources for formation of jet cooled radicals, and iii) high sensitivity detection with direct laser absorption methods and near the quantum shot noise limit. What makes this combination powerful is that such transients can be made under high concentrations and pressures characteristic of actual combustion conditions, and yet with the resulting species rapidly cooled (T ≈10-15K) in the slit supersonic expansion. Combined with the power of IR laser absorption methods, this provides novel access to spectral detection and study of many critical combustion species.

  18. Kinetics of wet sodium vapor complex plasma

    SciTech Connect (OSTI)

    Mishra, S. K., E-mail: nishfeb@rediffmail.com [Institute for Plasma Research (IPR), Gandhinagar 382428 (India); Sodha, M. S. [Centre of Energy Studies, Indian Institute of Technology Delhi (IITD), New Delhi 110016 (India)] [Centre of Energy Studies, Indian Institute of Technology Delhi (IITD), New Delhi 110016 (India)

    2014-04-15

    In this paper, we have investigated the kinetics of wet (partially condensed) Sodium vapor, which comprises of electrons, ions, neutral atoms, and Sodium droplets (i) in thermal equilibrium and (ii) when irradiated by light. The formulation includes the balance of charge over the droplets, number balance of the plasma constituents, and energy balance of the electrons. In order to evaluate the droplet charge, a phenomenon for de-charging of the droplets, viz., evaporation of positive Sodium ions from the surface has been considered in addition to electron emission and electron/ion accretion. The analysis has been utilized to evaluate the steady state parameters of such complex plasmas (i) in thermal equilibrium and (ii) when irradiated; the results have been graphically illustrated. As a significant outcome irradiated, Sodium droplets are seen to acquire large positive potential, with consequent enhancement in the electron density.

  19. Code System for 2-Group, 3D Neutronic Kinetics Calculations Coupled to Core Thermal Hydraulics.

    Energy Science and Technology Software Center (OSTI)

    2000-05-12

    Version 00 QUARK is a combined computer program comprising a revised version of the QUANDRY three-dimensional, two-group neutron kinetics code and an upgraded version of the COBRA transient core analysis code (COBRA-EN). Starting from either a critical steady-state (k-effective or critical dilute Boron problem) or a subcritical steady-state (fixed source problem) in a PWR plant, the code allows one to simulate the neutronic and thermal-hydraulic core transient response to reactivity accidents initiated both inside themore » vessel (such as a control rod ejection) and outside the vessel (such as the sudden change of the Boron concentration in the coolant). QUARK output can be used as input to PSR-470/NORMA-FP to perform a subchannel analysis from converged coarse-mesh nodal solutions.« less

  20. Fully kinetic simulations of megajoule-scale dense plasma focus

    SciTech Connect (OSTI)

    Schmidt, A.; Link, A.; Tang, V.; Halvorson, C.; May, M.; Welch, D.; Meehan, B. T.; Hagen, E. C.

    2014-10-15

    Dense plasma focus (DPF) Z-pinch devices are sources of copious high energy electrons and ions, x-rays, and neutrons. Megajoule-scale DPFs can generate 10{sup 12} neutrons per pulse in deuterium gas through a combination of thermonuclear and beam-target fusion. However, the details of the neutron production are not fully understood and past optimization efforts of these devices have been largely empirical. Previously, we reported on the first fully kinetic simulations of a kilojoule-scale DPF and demonstrated that both kinetic ions and kinetic electrons are needed to reproduce experimentally observed features, such as charged-particle beam formation and anomalous resistivity. Here, we present the first fully kinetic simulation of a MegaJoule DPF, with predicted ion and neutron spectra, neutron anisotropy, neutron spot size, and time history of neutron production. The total yield predicted by the simulation is in agreement with measured values, validating the kinetic model in a second energy regime.

  1. HIGH PRESSURE COAL COMBUSTON KINETICS PROJECT

    SciTech Connect (OSTI)

    Stefano Orsino

    2005-03-30

    As part of the U.S. Department of Energy (DoE) initiative to improve the efficiency of coal-fired power plants and reduce the pollution generated by these facilities, DOE has funded the High-Pressure Coal Combustion Kinetics (HPCCK) Projects. A series of laboratory experiments were conducted on selected pulverized coals at elevated pressures with the specific goals to provide new data for pressurized coal combustion that will help extend to high pressure and validate models for burnout, pollutant formation, and generate samples of solid combustion products for analyses to fill crucial gaps in knowledge of char morphology and fly ash formation. Two series of high-pressure coal combustion experiments were performed using SRI's pressurized radiant coal flow reactor. The first series of tests characterized the near burner flame zone (NBFZ). Three coals were tested, two high volatile bituminous (Pittsburgh No.8 and Illinois No.6), and one sub-bituminous (Powder River Basin), at pressures of 1, 2, and 3 MPa (10, 20, and 30 atm). The second series of experiments, which covered high-pressure burnout (HPBO) conditions, utilized a range of substantially longer combustion residence times to produce char burnout levels from 50% to 100%. The same three coals were tested at 1, 2, and 3 MPa, as well as at 0.2 MPa. Tests were also conducted on Pittsburgh No.8 coal in CO2 entrainment gas at 0.2, 1, and 2 MPa to begin establishing a database of experiments relevant to carbon sequestration techniques. The HPBO test series included use of an impactor-type particle sampler to measure the particle size distribution of fly ash produced under complete burnout conditions. The collected data have been interpreted with the help of CFD and detailed kinetics simulation to extend and validate devolatilization, char combustion and pollutant model at elevated pressure. A global NOX production sub-model has been proposed. The submodel reproduces the performance of the detailed chemical reaction

  2. Solitary kinetic Alfven waves in dusty plasmas

    SciTech Connect (OSTI)

    Li Yangfang; Wu, D. J.; Morfill, G. E.

    2008-08-15

    Solitary kinetic Alfven waves in dusty plasmas are studied by considering the dust charge variation. The effect of the dust charge-to-mass ratio on the soliton solution is discussed. The Sagdeev potential is derived analytically with constant dust charge and then calculated numerically by taking the dust charge variation into account. We show that the dust charge-to-mass ratio plays an important role in the soliton properties. The soliton solutions are comprised of two branches. One branch is sub-Alfvenic and the soliton velocity is obviously smaller than the Alfven speed. The other branch is super-Alfvenic and the soliton velocity is very close to or greater than the Alfven speed. Both compressive and rarefactive solitons can exist. For the sub-Alfvenic branch, the rarefactive soliton is bell-shaped and it is much narrower than the compressive one. However, for the super-Alfvenic branch, the compressive soliton is bell-shaped and narrower, and the rarefactive one is broadened. When the charge-to-mass ratio of the dust grains is sufficiently high, the width of the rarefactive soliton, in the super-Alfvenic branch, will broaden extremely and a electron depletion will be observed. It is also shown that the bell-shaped soliton can transition to a cusped structure when the velocity is sufficiently high.

  3. Advances in electron kinetics and theory of gas discharges

    SciTech Connect (OSTI)

    Kolobov, Vladimir I.; The University of Alabama in Huntsville, Huntsville, Alabama 35899

    2013-10-15

    “Electrons, like people, are fertile and infertile: high-energy electrons are fertile and able to reproduce.”—Lev TsendinModern physics of gas discharges increasingly uses physical kinetics for analysis of non-equilibrium plasmas. The description of underlying physics at the kinetic level appears to be important for plasma applications in modern technologies. In this paper, we attempt to grasp the legacy of Professor Lev Tsendin, who advocated the use of the kinetic approach for understanding fundamental problems of gas discharges. We outline the fundamentals of electron kinetics in low-temperature plasmas, describe elements of the modern kinetic theory of gas discharges, and show examples of the theoretical approach to gas discharge problems used by Lev Tsendin. Important connections between electron kinetics in gas discharges and semiconductors are also discussed. Using several examples, we illustrate how Tsendin's ideas and methods are currently being developed for the implementation of next generation computational tools for adaptive kinetic-fluid simulations of gas discharges used in modern technologies.

  4. Kinetic model for anaerobic digestion of biogas biological sludge

    SciTech Connect (OSTI)

    Pavlostathis, S.G.; Gossett, J.M.

    1986-10-01

    The principal objective of this study was the development and evaluation of a comprehensive kinetic model capable of predicting digester performance when fed biological sludge. Preliminary conversion mechanisms such as cell deaths, lysis, and hydrolysis responsible for rendering viable biological sludge organisms to available substrate were studied in depth. The results of this study indicate that hydrolysis of the dead, particulate biomass - primarily consisting of protein - is the slowest step, and therefore kinetically controls the overall process of an anaerobic digestion of biological sludge. A kinetic model was developed which could accurately describe digester performance and predict effluent quality.

  5. Zero kinetic energy photoelectron spectroscopy of triphenylene

    SciTech Connect (OSTI)

    Harthcock, Colin; Zhang, Jie; Kong, Wei

    2014-06-28

    We report vibrational information of both the first electronically excited state and the ground cationic state of jet-cooled triphenylene via the techniques of resonantly enhanced multiphoton ionization (REMPI) and zero kinetic energy (ZEKE) photoelectron spectroscopy. The first excited electronic state S{sub 1} of the neutral molecule is of A{sub 1}? symmetry and is therefore electric dipole forbidden in the D{sub 3h} group. Consequently, there are no observable Franck-Condon allowed totally symmetric a{sub 1}? vibrational bands in the REMPI spectrum. All observed vibrational transitions are due to Herzberg-Teller vibronic coupling to the E? third electronically excited state S{sub 3}. The assignment of all vibrational bands as e? symmetry is based on comparisons with calculations using the time dependent density functional theory and spectroscopic simulations. When an electron is eliminated, the molecular frame undergoes Jahn-Teller distortion, lowering the point group to C{sub 2v} and resulting in two nearly degenerate electronic states of A{sub 2} and B{sub 1} symmetry. Here we follow a crude treatment by assuming that all e? vibrational modes resolve into b{sub 2} and a{sub 1} modes in the C{sub 2v} molecular frame. Some observed ZEKE transitions are tentatively assigned, and the adiabatic ionization threshold is determined to be 63?365 7 cm{sup ?1}. The observed ZEKE spectra contain a consistent pattern, with a cluster of transitions centered near the same vibrational level of the cation as that of the intermediate state, roughly consistent with the propensity rule. However, complete assignment of the detailed vibrational structure due to Jahn-Teller coupling requires much more extensive calculations, which will be performed in the future.

  6. Kinetic and Performance Studies of the Regeneration Phase of...

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

    Phase of Model PtRhBa NOx Traps for Design and Optimization Kinetic and Performance Studies of the Regeneration Phase of Model PtRhBa NOx Traps for Design and ...

  7. Elucidating Hydrogen Oxidation/Evolution Kinetics in Base and...

    Office of Scientific and Technical Information (OSTI)

    Elucidating Hydrogen OxidationEvolution Kinetics in Base and Acid by Enhanced Activities at the Optimized Pt Shell Thickness on the Ru Core Citation Details In-Document Search...

  8. Explicit integration with GPU acceleration for large kinetic networks

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Brock, Benjamin; Belt, Andrew; Billings, Jay Jay; Guidry, Mike W.

    2015-09-15

    In this study, we demonstrate the first implementation of recently-developed fast explicit kinetic integration algorithms on modern graphics processing unit (GPU) accelerators. Taking as a generic test case a Type Ia supernova explosion with an extremely stiff thermonuclear network having 150 isotopic species and 1604 reactions coupled to hydrodynamics using operator splitting, we demonstrate the capability to solve of order 100 realistic kinetic networks in parallel in the same time that standard implicit methods can solve a single such network on a CPU. In addition, this orders-of-magnitude decrease in computation time for solving systems of realistic kinetic networks implies thatmore » important coupled, multiphysics problems in various scientific and technical fields that were intractable, or could be simulated only with highly schematic kinetic networks, are now computationally feasible.« less

  9. The LANL atomic kinetics modeling effort and its application...

    Office of Scientific and Technical Information (OSTI)

    effort and its application to W plasmas Citation Details In-Document Search Title: The LANL atomic kinetics modeling effort and its application to W plasmas This is the work of ...

  10. Benchmark Reaction Mechanisms and Kinetics for Lean NOx Traps...

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

    and Peer Evaluation Meeting, May 18-22, 2009 -- Washington D.C. PDF icon acep01larson.pdf More Documents & Publications Development of Chemical Kinetic Models for Lean NOx ...

  11. Pressure Dependent Decomposition Kinetics of the Energetic Material...

    Office of Scientific and Technical Information (OSTI)

    Kinetics of the Energetic Material HMX up to 3.6 GPa The effect of pressure on the thermal decomposition rate of the energetic material HMX was studied. HMX was...

  12. Intercalation Kinetics and Ion Mobility in Electrode Materials...

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

    es093daniel2011o.pdf More Documents & Publications Coupled Kinetic, Thermal, and Mechanical Modeling of FIB Micro-machined Electrodes In-Situ Electron Microscopy of Electrical ...

  13. Vehicle Technologies Office Merit Review 2016: Chemical Kinetic Models for

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

    Advanced Engine Combustion | Department of Energy Chemical Kinetic Models for Advanced Engine Combustion Vehicle Technologies Office Merit Review 2016: Chemical Kinetic Models for Advanced Engine Combustion Presentation given by Lawrence Livermore National Laboratory (LLNL) at the 2016 DOE Vehicle Technologies Office and Hydrogen and Fuel Cells Program Annual Merit Review and Peer Evaluation Meeting about Combustion Engines ace013_pitz_2016_o_web.pdf (1.99 MB) More Documents &

  14. Exploring Competing Kinetic Processes in Quantum Dots Linked to Electrode

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

    Surfaces | MIT-Harvard Center for Excitonics Competing Kinetic Processes in Quantum Dots Linked to Electrode Surfaces March 14, 2012 at 2:30pm/4-349 Mark Hybertsen Brookhaven National Laboratory, Columbia University Mark_Hybertsen001_000 Abstract: Exploiting the unique properties of nanostructured chromophores for light harvesting applications relies on the balance between competing kinetic processes including energy transfer, carrier relaxation and carrier tunneling. In the first part of

  15. Extraction of Equilibrium Energy and Kinetic Parameters from Single

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

    Molecule Force Spectroscopy Data Alex Noy is the Principal Investigator for the Extraction of Equilibrium Energy and Kinetic Parameters from Single Molecule Force Spectroscopy Data. LLNL BES Programs Highlight Extraction of Equilibrium Energy and Kinetic Parameters from Single Molecule Force Spectroscopy Data Dynamic strength data for 10 different biological bonds fitted by the model R.W. Friddle, A. Noy, J.J. De Yoreo, Interpreting the widespread nonlinear force spectra of intermolecular

  16. Point kinetics calculations with fully coupled thermal fluids reactivity feedback

    SciTech Connect (OSTI)

    Zhang, H.; Zou, L.; Andrs, D.; Zhao, H.; Martineau, R.

    2013-07-01

    The point kinetics model has been widely used in the analysis of the transient behavior of a nuclear reactor. In the traditional nuclear reactor system safety analysis codes such as RELAP5, the reactivity feedback effects are calculated in a loosely coupled fashion through operator splitting approach. This paper discusses the point kinetics calculations with the fully coupled thermal fluids and fuel temperature feedback implemented into the RELAP-7 code currently being developed with the MOOSE framework. (authors)

  17. Ultrafast kinetics subsequent to shock in an unreacted, oxygen balanced

    Office of Scientific and Technical Information (OSTI)

    mixture of nitromethane and hydrogen peroxide (Conference) | SciTech Connect kinetics subsequent to shock in an unreacted, oxygen balanced mixture of nitromethane and hydrogen peroxide Citation Details In-Document Search Title: Ultrafast kinetics subsequent to shock in an unreacted, oxygen balanced mixture of nitromethane and hydrogen peroxide Authors: Armstrong, M R ; Zaug, J M ; Grant, C D ; Crowhurst, J C ; Bastea, S Publication Date: 2014-06-24 OSTI Identifier: 1149544 Report Number(s):

  18. Kinetic Theory of Turbulent Multiphase Flow | The Ames Laboratory

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

    Kinetic Theory of Turbulent Multiphase Flow FWP/Project Description: Project Leader(s): Rodney Fox It is proposed to further the present understanding of turbulent gas-solid fluidized-bed reactors from the conceptual standpoint of kinetic theory and turbulence modeling. The primary purpose is to provide a theoretical underpinning for the construction of computer codes to better understand and predict multiphase flow behavior in polydisperse gas-solid fluidized-bed reactors and risers. In

  19. Consistent description of kinetics and hydrodynamics of dusty plasma

    SciTech Connect (OSTI)

    Markiv, B.; Tokarchuk, M.; National University Lviv Polytechnic, 12 Bandera St., 79013 Lviv

    2014-02-15

    A consistent statistical description of kinetics and hydrodynamics of dusty plasma is proposed based on the Zubarev nonequilibrium statistical operator method. For the case of partial dynamics, the nonequilibrium statistical operator and the generalized transport equations for a consistent description of kinetics of dust particles and hydrodynamics of electrons, ions, and neutral atoms are obtained. In the approximation of weakly nonequilibrium process, a spectrum of collective excitations of dusty plasma is investigated in the hydrodynamic limit.

  20. Doc...~En.

    Office of Legacy Management (LM)

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  1. Peptide concentration alters intermediate species in amyloid ? fibrillation kinetics

    SciTech Connect (OSTI)

    Garvey, M., E-mail: megan.garvey@molbiotech.rwth-aachen.de [Max-Planck Research Unit for Enzymology of Protein Folding, Weinbergweg 22, 06120 Halle (Saale) (Germany); Morgado, I., E-mail: immorgado@ualg.pt [Max-Planck Research Unit for Enzymology of Protein Folding, Weinbergweg 22, 06120 Halle (Saale) (Germany)

    2013-04-12

    Highlights: ? A?(140) aggregation in vitro has been monitored at different concentrations. ? A?(140) fibrillation does not always follow conventional kinetic mechanisms. ? We demonstrate non-linear features in the kinetics of A?(140) fibril formation. ? At high A?(140) concentrations secondary processes dictate fibrillation speed. ? Intermediate species may play significant roles on final amyloid fibril development. -- Abstract: The kinetic mechanism of amyloid aggregation remains to be fully understood. Investigations into the species present in the different kinetic phases can assist our comprehension of amyloid diseases and further our understanding of the mechanism behind amyloid ? (A?) (140) peptide aggregation. Thioflavin T (ThT) fluorescence and transmission electron microscopy (TEM) have been used in combination to monitor A?(140) aggregation in vitro at both normal and higher than standard concentrations. The observed fibrillation behaviour deviates, in several respects, from standard concepts of the nucleationpolymerisation models and shows such features as concentration-dependent non-linear effects in the assembly mechanism. A?(140) fibrillation kinetics do not always follow conventional kinetic mechanisms and, specifically at high concentrations, intermediate structures become populated and secondary processes may further modify the fibrillation mechanism.

  2. The Impact of Alternative Fuels on Combustion Kinetics

    SciTech Connect (OSTI)

    Pitz, W J; Westbrook, C K

    2009-07-30

    The research targets the development of detailed kinetic models to quantitatively characterize the impact of alternative fuels on the performance of Navy turbines and diesel engines. Such impacts include kinetic properties such as cetane number, flame speed, and emissions as well as physical properties such as the impact of boiling point distributions on fuel vaporization and mixing. The primary focus will be Fischer-Tropsch liquids made from natural gas, coal or biomass. The models will include both the effects of operation with these alternative fuels as well as blends of these fuels with conventional petroleum-based fuels. The team will develop the requisite kinetic rules for specific reaction types and incorporate these into detailed kinetic mechanisms to predict the combustion performance of neat alternative fuels as well as blends of these fuels with conventional fuels. Reduced kinetic models will be then developed to allow solution of the coupled kinetics/transport problems. This is a collaboration between the Colorado School of Mines (CSM) and the Lawrence Livermore National Laboratory (LLNL). The CSM/LLNL team plans to build on the substantial progress made in recent years in developing accurate detailed chemical mechanisms for the oxidation and pyrolysis of conventional fuels. Particular emphasis will be placed upon reactions of the isoalkanes and the daughter radicals, especially tertiary radicals, formed by abstraction from the isoalkanes. The various components of the program are described. We have been developing the kinetic models for two iso-dodecane molecules, using the same kinetic modeling formalisms that were developed for the gasoline and diesel primary reference fuels. These mechanisms, and the thermochemical and transport coefficient submodels for them, are very close to completion at the time of this report, and we expect them to be available for kinetic simulations early in the coming year. They will provide a basis for prediction and

  3. Chemical kinetic modeling of H{sub 2} applications

    SciTech Connect (OSTI)

    Marinov, N.M.; Westbrook, C.K.; Cloutman, L.D.

    1995-09-01

    Work being carried out at LLNL has concentrated on studies of the role of chemical kinetics in a variety of problems related to hydrogen combustion in practical combustion systems, with an emphasis on vehicle propulsion. Use of hydrogen offers significant advantages over fossil fuels, and computer modeling provides advantages when used in concert with experimental studies. Many numerical {open_quotes}experiments{close_quotes} can be carried out quickly and efficiently, reducing the cost and time of system development, and many new and speculative concepts can be screened to identify those with sufficient promise to pursue experimentally. This project uses chemical kinetic and fluid dynamic computational modeling to examine the combustion characteristics of systems burning hydrogen, either as the only fuel or mixed with natural gas. Oxidation kinetics are combined with pollutant formation kinetics, including formation of oxides of nitrogen but also including air toxics in natural gas combustion. We have refined many of the elementary kinetic reaction steps in the detailed reaction mechanism for hydrogen oxidation. To extend the model to pressures characteristic of internal combustion engines, it was necessary to apply theoretical pressure falloff formalisms for several key steps in the reaction mechanism. We have continued development of simplified reaction mechanisms for hydrogen oxidation, we have implemented those mechanisms into multidimensional computational fluid dynamics models, and we have used models of chemistry and fluid dynamics to address selected application problems. At the present time, we are using computed high pressure flame, and auto-ignition data to further refine the simplified kinetics models that are then to be used in multidimensional fluid mechanics models. Detailed kinetics studies have investigated hydrogen flames and ignition of hydrogen behind shock waves, intended to refine the detailed reactions mechanisms.

  4. Performance of non-conventional factorization approaches for neutron kinetics

    SciTech Connect (OSTI)

    Bulla, S.; Nervo, M.

    2013-07-01

    The use of factorization techniques provides a interesting option for the simulation of the time-dependent behavior of nuclear systems with a reduced computational effort. While point kinetics neglects all spatial and spectral effects, quasi-statics and multipoint kinetics allow to produce results with a higher accuracy for transients involving relevant modifications of the neutron distribution. However, in some conditions these methods can not work efficiently. In this paper, we discuss some possible alternative formulations for the factorization process for neutron kinetics, leading to mathematical models of reduced complications that can allow an accurate simulation of transients involving spatial and spectral effects. The performance of these innovative approaches are compared to standard techniques for some test cases, showing the benefits and shortcomings of the method proposed. (authors)

  5. Kinetics of the carbon monoxide oxidation reaction under microwave heating

    SciTech Connect (OSTI)

    Perry, W.L.; Katz, J.D.; Rees, D.; Paffett, M.T. [Los Alamos National Lab., NM (United States); Datye, A. [Univ. of New Mexico, Albuquerque, NM (United States)

    1996-06-01

    915 MHz microwave heating has been used to drive the CO oxidation reaction over Pd/Al{sub 2}O{sub 3} with out significantly affecting the reaction kinetics. As compared to an identical conventionally heated system, the activation energy, pre-exponential factor, and reaction order with respect to CO were unchanged. Temperature was measured using a thermocouple extrapolation technique. Microwave-induced thermal gradients were found to play a significant role in kinetic observations. The authors chose the CO oxidation reaction over a supported metal catalyst because the reaction kinetics are well known, and because of the diverse dielectric properties of the various elements in the system: CO is a polar molecule, O{sub 2} and CO{sub 2} are non-polar, Al{sub 2}O{sub 3} is a dielectric, and Pt and Pd are conductors.

  6. Global limits on kinetic Alfvenon speed in quasineutral plasmas

    SciTech Connect (OSTI)

    Akbari-Moghanjoughi, M.

    2011-04-15

    Large-amplitude kinetic Alfvenon (exact Alfven soliton) matching condition is investigated in quasineutral electron-ion and electron-positron-ion plasmas immersed in a uniform magnetic field. Using the standard pseudopotential method, the magnetohydrodynamics equations are exactly solved, and a global allowed matching condition for propagation of kinetic solitary waves is derived. It is remarked that, depending on the plasma parameters, the kinetic solitons can be sub-Alfvenic or super-Alfvenic, in general. It is further revealed that, either upper or lower soliton speed-limit is independent of fractional plasma parameters. Furthermore, the soliton propagation angle with respect to that of the uniform magnetic field is found to play a fundamental role in controlling the soliton matching speed-range.

  7. Chemical Kinetic Models for HCCI and Diesel Combustion

    SciTech Connect (OSTI)

    Pitz, W J; Westbrook, C K; Mehl, M; Sarathy, S M

    2010-11-15

    Predictive engine simulation models are needed to make rapid progress towards DOE's goals of increasing combustion engine efficiency and reducing pollutant emissions. These engine simulation models require chemical kinetic submodels to allow the prediction of the effect of fuel composition on engine performance and emissions. Chemical kinetic models for conventional and next-generation transportation fuels need to be developed so that engine simulation tools can predict fuel effects. The objectives are to: (1) Develop detailed chemical kinetic models for fuel components used in surrogate fuels for diesel and HCCI engines; (2) Develop surrogate fuel models to represent real fuels and model low temperature combustion strategies in HCCI and diesel engines that lead to low emissions and high efficiency; and (3) Characterize the role of fuel composition on low temperature combustion modes of advanced combustion engines.

  8. Kinetics of high-conversion hydrocracking of bitumen

    SciTech Connect (OSTI)

    Nagaishi, H.; Gray, M.R.; Chan, E.W.; Sanford, E.C.

    1995-12-31

    Residues are complex mixtures of thousands of components. This mixture will change during hydrocracking, so that high conversion may result in a residue material with different characteristics from the starting material. Our objective is to determine the kinetics of residue conversion and yields of distillates at high conversions, and to relate these observations to the underlying chemical reactions. Athabasca bitumen was reacted in a 1-L CSTR in a multipass operation. Product from the first pass was collected, then run through the reactor again and so on, giving kinetic data under conditions that simulated a multi-reactor or packed-bed operation. Experiments were run both with hydrocracking catalyst and without added catalyst. Products were analyzed by distillation, elemental analysis, NMR, and GPC. These data will be used to derive a kinetic model for hydrocracking of bitumen residue covering a wide range of conversion (from 30% to 95%+), based on the underlying chemistry.

  9. Kinetic Alfvn wave turbulence and formation of localized structures

    SciTech Connect (OSTI)

    Sharma, R. P.; Modi, K. V.; Mechanical Engineering Department, Government Engineering College Valsad, Gujarat 396001

    2013-08-15

    This work presents non-linear interaction of magnetosonic wave with kinetic Alfvn wave for intermediate ?-plasma (m{sub e}/m{sub i}???1). A set of dimensionless equations have been developed for analysis by considering ponderomotive force due to pump kinetic Alfvn wave in the dynamics of magnetosonic wave. Stability analysis has been done to study modulational instability or linear growth rate. Further, numerical simulation has been carried out to study the nonlinear stage of instability and resulting power spectrum applicable to solar wind around 1 AU. Due to the nonlinearity, background density of magnetosonic wave gets modified which results in localization of kinetic Alfvn wave. From the obtained results, we observed that spectral index follows k{sup ?3.0}, consistent with observation received by Cluster spacecraft for the solar wind around 1 AU. The result shows the steepening of power spectrum which may be responsible for heating and acceleration of plasma particles in solar wind.

  10. Computer-Aided Construction of Chemical Kinetic Models

    SciTech Connect (OSTI)

    Green, William H.

    2014-12-31

    The combustion chemistry of even simple fuels can be extremely complex, involving hundreds or thousands of kinetically significant species. The most reasonable way to deal with this complexity is to use a computer not only to numerically solve the kinetic model, but also to construct the kinetic model in the first place. Because these large models contain so many numerical parameters (e.g. rate coefficients, thermochemistry) one never has sufficient data to uniquely determine them all experimentally. Instead one must work in predictive mode, using theoretical rather than experimental values for many of the numbers in the model, and as appropriate refining the most sensitive numbers through experiments. Predictive chemical kinetics is exactly what is needed for computer-aided design of combustion systems based on proposed alternative fuels, particularly for early assessment of the value and viability of proposed new fuels before those fuels are commercially available. This project was aimed at making accurate predictive chemical kinetics practical; this is a challenging goal which requires a range of science advances. The project spanned a wide range from quantum chemical calculations on individual molecules and elementary-step reactions, through the development of improved rate/thermo calculation procedures, the creation of algorithms and software for constructing and solving kinetic simulations, the invention of methods for model-reduction while maintaining error control, and finally comparisons with experiment. Many of the parameters in the models were derived from quantum chemistry calculations, and the models were compared with experimental data measured in our lab or in collaboration with others.

  11. Benchmarking kinetic calculations of resistive wall mode stability

    SciTech Connect (OSTI)

    Berkery, J. W.; Sabbagh, S. A.; Liu, Y. Q.; Betti, R.

    2014-05-15

    Validating the calculations of kinetic resistive wall mode (RWM) stability is important for confidently predicting RWM stable operating regions in ITER and other high performance tokamaks for disruption avoidance. Benchmarking the calculations of the Magnetohydrodynamic Resistive SpectrumKinetic (MARS-K) [Y. Liu et al., Phys. Plasmas 15, 112503 (2008)], Modification to Ideal Stability by Kinetic effects (MISK) [B. Hu et al., Phys. Plasmas 12, 057301 (2005)], and Perturbed Equilibrium Nonambipolar Transport (PENT) [N. Logan et al., Phys. Plasmas 20, 122507 (2013)] codes for two Solov'ev analytical equilibria and a projected ITER equilibrium has demonstrated good agreement between the codes. The important particle frequencies, the frequency resonance energy integral in which they are used, the marginally stable eigenfunctions, perturbed Lagrangians, and fluid growth rates are all generally consistent between the codes. The most important kinetic effect at low rotation is the resonance between the mode rotation and the trapped thermal particle's precession drift, and MARS-K, MISK, and PENT show good agreement in this term. The different ways the rational surface contribution was treated historically in the codes is identified as a source of disagreement in the bounce and transit resonance terms at higher plasma rotation. Calculations from all of the codes support the present understanding that RWM stability can be increased by kinetic effects at low rotation through precession drift resonance and at high rotation by bounce and transit resonances, while intermediate rotation can remain susceptible to instability. The applicability of benchmarked kinetic stability calculations to experimental results is demonstrated by the prediction of MISK calculations of near marginal growth rates for experimental marginal stability points from the National Spherical Torus Experiment (NSTX) [M. Ono et al., Nucl. Fusion 40, 557 (2000)].

  12. Recent advances in the kinetics of oxygen reduction

    SciTech Connect (OSTI)

    Adzic, R.

    1996-07-01

    Oxygen reduction is considered an important electrocatalytic reaction; the most notable need remains improvement of the catalytic activity of existing metal electrocatalysts and development of new ones. A review is given of new advances in the understanding of reaction kinetics and improvements of the electrocatalytic properties of some surfaces, with focus on recent studies of relationship of the surface properties to its activity and reaction kinetics. The urgent need is to improve catalytic activity of Pt and synthesize new, possibly non- noble metal catalysts. New experimental techniques for obtaining new level of information include various {ital in situ} spectroscopies and scanning probes, some involving synchrotron radiation. 138 refs, 18 figs, 2 tabs.

  13. Spectroscopy and kinetics of combustion gases at high temperatures

    SciTech Connect (OSTI)

    Hanson, R.K.; Bowman, C.T.

    1993-12-01

    This program involves two complementary activities: (1) development and application of cw ring dye laser absorption methods for sensitive detection of radical species and measurement of fundamental spectroscopic parameters at high temperatures; and (2) shock tube studies of reaction kinetics relevant to combustion. Species currently under investigation in the spectroscopic portion of the research include NO and CH{sub 3}; this has necessitated the continued operated at wavelengths in the range 210-230 nm. Shock tube studies of reaction kinetics currently are focussed on reactions involving CH{sub 3} radicals.

  14. Infrared absorption spectroscopy and chemical kinetics of free radicals

    SciTech Connect (OSTI)

    Curl, R.F.; Glass, G.P.

    1993-12-01

    This research is directed at the detection, monitoring, and study of chemical kinetic behavior by infrared absorption spectroscopy of small free radical species thought to be important intermediates in combustion. During the last year, infrared kinetic spectroscopy using excimer laser flash photolysis and color-center laser probing has been employed to study the high resolution spectrum of HCCN, the rate constant of the reaction between ethynyl (C{sub 2}H) radical and H{sub 2} in the temperature region between 295 and 875 K, and the recombination rate of propargyl (CH{sub 2}CCH) at room temperature.

  15. General non-minimal kinetic coupling to gravity

    SciTech Connect (OSTI)

    Granda, L.N.; Cardona, W. E-mail: wilalbca@univalle.edu.co

    2010-07-01

    We study a model of scalar field with a general non-minimal kinetic coupling to itself and to the curvature, as a source of dark energy, and analyze the cosmological dynamics of this model and the issue of accelerated expansion. Solutions giving rise to power-law expansion have been found. The dynamical equation of state is studied for the two cases, without and with free kinetic term . In the first case, a behavior very close to that of the cosmological constant was found. In the second case, a solution was found, which match the current phenomenology of the dark energy. The model shows a rich variety of dynamical scenarios.

  16. A coke oven model including thermal decomposition kinetics of tar

    SciTech Connect (OSTI)

    Munekane, Fuminori; Yamaguchi, Yukio; Tanioka, Seiichi

    1997-12-31

    A new one-dimensional coke oven model has been developed for simulating the amount and the characteristics of by-products such as tar and gas as well as coke. This model consists of both heat transfer and chemical kinetics including thermal decomposition of coal and tar. The chemical kinetics constants are obtained by estimation based on the results of experiments conducted to investigate the thermal decomposition of both coal and tar. The calculation results using the new model are in good agreement with experimental ones.

  17. Kinetic Activation-Relaxation Technique and Self-Evolving Atomistic Kinetic Monte Carlo: Comparison of on-the-fly kinetic Monte Carlo algorithms

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Beland, Laurent Karim; Osetskiy, Yury N.; Stoller, Roger E.; Xu, Haixuan

    2015-02-07

    Here, we present a comparison of the Kinetic Activation–Relaxation Technique (k-ART) and the Self-Evolving Atomistic Kinetic Monte Carlo (SEAKMC), two off-lattice, on-the-fly Kinetic Monte Carlo (KMC) techniques that were recently used to solve several materials science problems. We show that if the initial displacements are localized the dimer method and the Activation–Relaxation Technique nouveau provide similar performance. We also show that k-ART and SEAKMC, although based on different approximations, are in agreement with each other, as demonstrated by the examples of 50 vacancies in a 1950-atom Fe box and of interstitial loops in 16,000-atom boxes. Generally speaking, k-ART’s treatment ofmore » geometry and flickers is more flexible, e.g. it can handle amorphous systems, and rigorous than SEAKMC’s, while the later’s concept of active volumes permits a significant speedup of simulations for the systems under consideration and therefore allows investigations of processes requiring large systems that are not accessible if not localizing calculations.« less

  18. Kinetics of steel slag leaching: Batch tests and modeling

    SciTech Connect (OSTI)

    De Windt, Laurent; Chaurand, Perrine; Rose, Jerome

    2011-02-15

    Reusing steel slag as an aggregate for road construction requires to characterize the leaching kinetics and metal releases. In this study, basic oxygen furnace (BOF) steel slag were subjected to batch leaching tests at liquid to solid ratios (L/S) of 10 and 100 over 30 days; the leachate chemistry being regularly sampled in time. A geochemical model of the steel slag is developed and validated from experimental data, particularly the evolution with leaching of mineralogical composition of the slag and trace element speciation. Kinetics is necessary for modeling the primary phase leaching, whereas a simple thermodynamic equilibrium approach can be used for secondary phase precipitation. The proposed model simulates the kinetically-controlled dissolution (hydrolysis) of primary phases, the precipitation of secondary phases (C-S-H, hydroxide and spinel), the pH and redox conditions, and the progressive release of major elements as well as the metals Cr and V. Modeling indicates that the dilution effect of the L/S ratio is often coupled to solubility-controlled processes, which are sensitive to both the pH and the redox potential. A sensitivity analysis of kinetic uncertainties on the modeling of element releases is performed.

  19. Desorption Kinetics of Methanol, Ethanol, and Water from Graphene

    SciTech Connect (OSTI)

    Smith, R. Scott; Matthiesen, Jesper; Kay, Bruce D.

    2014-09-18

    The desorption kinetics of methanol, ethanol, and water from graphene covered Pt(111) are investigated. The temperature programmed desorption (TPD) spectra for both methanol and ethanol have well-resolved first, second, third, and multilayer layer desorption peaks. The alignment of the leading edges is consistent with zero-order desorption kinetics from all layers. In contrast, for water the first and second layers are not resolved. At low water coverages (< 1 ML) the initial desorption leading edges are aligned but then fall out of alignment at higher temperatures. For thicker water layers (10 to 100 ML), the desorption leading edges are in alignment throughout the desorption of the film. The coverage dependence of the desorption behavoir suggests that at low water coverages the non-alignment of the desorption leading edges is due to water dewetting from the graphene substrate. Kinetic simulations reveal that the experimental results are consistent with zero-order desorption. The simulations also show that fractional order desorption kinetics would be readily apparent in the experimental TPD spectra.

  20. Detailed chemical kinetic oxidation mechanism for a biodiesel surrogate

    SciTech Connect (OSTI)

    Herbinet, O; Pitz, W J; Westbrook, C K

    2007-09-17

    A detailed chemical kinetic mechanism has been developed and used to study the oxidation of methyl decanoate, a surrogate for biodiesel fuels. This model has been built by following the rules established by Curran et al. for the oxidation of n-heptane and it includes all the reactions known to be pertinent to both low and high temperatures. Computed results have been compared with methyl decanoate experiments in an engine and oxidation of rapeseed oil methyl esters in a jet stirred reactor. An important feature of this mechanism is its ability to reproduce the early formation of carbon dioxide that is unique to biofuels and due to the presence of the ester group in the reactant. The model also predicts ignition delay times and OH profiles very close to observed values in shock tube experiments fueled by n-decane. These model capabilities indicate that large n-alkanes can be good surrogates for large methyl esters and biodiesel fuels to predict overall reactivity, but some kinetic details, including early CO2 production from biodiesel fuels, can be predicted only by a detailed kinetic mechanism for a true methyl ester fuel. The present methyl decanoate mechanism provides a realistic kinetic tool for simulation of biodiesel fuels.

  1. Detailed chemical kinetic oxidation mechanism for a biodiesel surrogate

    SciTech Connect (OSTI)

    Herbinet, O; Pitz, W J; Westbrook, C K

    2007-09-20

    A detailed chemical kinetic mechanism has been developed and used to study the oxidation of methyl decanoate, a surrogate for biodiesel fuels. This model has been built by following the rules established by Curran et al. for the oxidation of n-heptane and it includes all the reactions known to be pertinent to both low and high temperatures. Computed results have been compared with methyl decanoate experiments in an engine and oxidation of rapeseed oil methyl esters in a jet stirred reactor. An important feature of this mechanism is its ability to reproduce the early formation of carbon dioxide that is unique to biofuels and due to the presence of the ester group in the reactant. The model also predicts ignition delay times and OH profiles very close to observed values in shock tube experiments fueled by n-decane. These model capabilities indicate that large n-alkanes can be good surrogates for large methyl esters and biodiesel fuels to predict overall reactivity, but some kinetic details, including early CO{sub 2} production from biodiesel fuels, can be predicted only by a detailed kinetic mechanism for a true methyl ester fuel. The present methyl decanoate mechanism provides a realistic kinetic tool for simulation of biodiesel fuels.

  2. Detailed chemical kinetic oxidation mechanism for a biodiesel surrogate

    SciTech Connect (OSTI)

    Herbinet, Olivier; Pitz, William J.; Westbrook, Charles K.

    2008-08-15

    A detailed chemical kinetic mechanism has been developed and used to study the oxidation of methyl decanoate, a surrogate for biodiesel fuels. This model has been built by following the rules established by Curran and co-workers for the oxidation of n-heptane and it includes all the reactions known to be pertinent to both low and high temperatures. Computed results have been compared with methyl decanoate experiments in an engine and oxidation of rapeseed oil methyl esters in a jet-stirred reactor. An important feature of this mechanism is its ability to reproduce the early formation of carbon dioxide that is unique to biofuels and due to the presence of the ester group in the reactant. The model also predicts ignition delay times and OH profiles very close to observed values in shock tube experiments fueled by n-decane. These model capabilities indicate that large n-alkanes can be good surrogates for large methyl esters and biodiesel fuels to predict overall reactivity, but some kinetic details, including early CO{sub 2} production from biodiesel fuels, can be predicted only by a detailed kinetic mechanism for a true methyl ester fuel. The present methyl decanoate mechanism provides a realistic kinetic tool for simulation of biodiesel fuels. (author)

  3. KINETICS OF SLURRY PHASE FISCHER-TROPSCH SYNTHESIS

    SciTech Connect (OSTI)

    Dragomir B. Bukur; Gilbert F. Froment; Tomasz Olewski

    2006-09-29

    This report covers the fourth year of a research project conducted under the University Coal Research Program. The overall objective of this project is to develop a comprehensive kinetic model for slurry-phase Fischer-Tropsch synthesis (FTS) employing iron-based catalysts. This model will be validated with experimental data obtained in a stirred-tank slurry reactor (STSR) over a wide range of process conditions. The model will be able to predict molar flow rates and concentrations of all reactants and major product species (water, carbon dioxide, linear 1- and 2-olefins, and linear paraffins) as a function of reaction conditions in the STSR. During the fourth year of the project, an analysis of experimental data collected during the second year of this project was performed. Kinetic parameters were estimated utilizing product distributions from 27 mass balances. During the reporting period two kinetic models were employed: a comprehensive kinetic model of Dr. Li and co-workers (Yang et al., 2003) and a hydrocarbon selectivity model of Van der Laan and Beenackers (1998, 1999) The kinetic model of Yang et al. (2003) has 24 parameters (20 parameters for hydrocarbon formation, and 4 parameters for the water-gas-shift (WGS) reaction). Kinetic parameters for the WGS reaction and FTS synthesis were estimated first separately, and then simultaneously. The estimation of these kinetic parameters employed the Levenberg-Marquardt (LM) method and the trust-region reflective Newton large-scale (LS) method. A genetic algorithm (GA) was incorporated into estimation of parameters for FTS reaction to provide initial estimates of model parameters. All reaction rate constants and activation energies were found to be positive, but at the 95% confidence level the intervals were large. Agreement between predicted and experimental reaction rates has been fair to good. Light hydrocarbons are predicted fairly accurately, whereas the model underpredicts values of higher molecular weight

  4. TOTAL SES SL EJ//EK EN IV EN III

    National Nuclear Security Administration (NNSA)

    SL EJEK EN IV EN III NN (Engineering) NQ (ProfTechAdmin) NU (TechAdminSupport) RETIREMENT ELIGIBLE TO RETIRE IMMEDIATELY 11 13.9% ELIGIBLE TO RETIRE BY 3272014 29 36.7%...

  5. Comment on "Kinetic theory for a mobile impurity in a degenerate...

    Office of Scientific and Technical Information (OSTI)

    Comment on "Kinetic theory for a mobile impurity in a degenerate Tonks-Girardeau gas" Citation Details In-Document Search Title: Comment on "Kinetic theory for a mobile impurity in ...

  6. Comment on "Kinetic theory for a mobile impurity in a degenerate...

    Office of Scientific and Technical Information (OSTI)

    Comment on "Kinetic theory for a mobile impurity in a degenerate Tonks-Girardeau gas" Title: Comment on "Kinetic theory for a mobile impurity in a degenerate Tonks-Girardeau gas" ...

  7. UCRL-JC-l20677 PREPRINT Detailed and Global Chemical Kinetics...

    Office of Scientific and Technical Information (OSTI)

    UCRL-JC-l20677 PREPRINT Detailed and Global Chemical Kinetics Model for Hydrogen N. M. ... Detailed and Global Chemical Kinetics Model For Hydrogen N.M. Marinov, C.K. Westbrook and ...

  8. Fully Kinetic Simulations of MegaJoule-Scale Dense Plasma Focus...

    Office of Scientific and Technical Information (OSTI)

    Journal Article: Fully Kinetic Simulations of MegaJoule-Scale Dense Plasma Focus Citation Details In-Document Search Title: Fully Kinetic Simulations of MegaJoule-Scale Dense ...

  9. Kinetics of Slurry Phase Fischer-Tropsch Synthesis

    SciTech Connect (OSTI)

    Dragomir B. Bukur; Gilbert F. Froment; Tomasz Olewski; Lech Nowicki; Madhav Nayapati

    2006-12-31

    The overall objective of this project is to develop a comprehensive kinetic model for slurry-phase Fischer-Tropsch synthesis (FTS) employing iron-based catalysts. This model will be validated with experimental data obtained in a stirred-tank slurry reactor (STSR) over a wide range of process conditions. Three STSR tests of the Ruhrchemie LP 33/81 catalyst were conducted to collect data on catalyst activity and selectivity under 25 different sets of process conditions. The observed decrease in 1-olefin content and increase in 2-olefin and n-paraffin contents with the increase in conversion are consistent with a concept that 1-olefins participate in secondary reactions (e.g. 1-olefin hydrogenation, isomerization and readsorption), whereas 2-olefins and n-paraffins are formed in these reactions. Carbon number product distribution showed an increase in chain growth probability with increase in chain length. Vapor-liquid equilibrium calculations were made to check validity of the assumption that the gas and liquid phases are in equilibrium during FTS in the STSR. Calculated vapor phase compositions were in excellent agreement with experimental values from the STSR under reaction conditions. Discrepancies between the calculated and experimental values for the liquid-phase composition (for some of the experimental data) are ascribed to experimental errors in the amount of wax collected from the reactor, and the relative amounts of hydrocarbon wax and Durasyn 164 oil (start-up fluid) in the liquid samples. Kinetic parameters of four kinetic models (Lox and Froment, 1993b; Yang et al., 2003; Van der Laan and Beenackers, 1998, 1999; and an extended kinetic model of Van der Laan and Beenackers) were estimated from experimental data in the STSR tests. Two of these kinetic models (Lox and Froment, 1993b; Yang et al., 2003) can predict a complete product distribution (inorganic species and hydrocarbons), whereas the kinetic model of Van der Laan and Beenackers (1998, 1999) can

  10. KINETIC MODELING OF FUEL EFFECTS OVER A WIDE RANGE OF CHEMISTRY...

    Office of Scientific and Technical Information (OSTI)

    Methodologies needed for studying fuel effects include development of fuel kinetic ... Resource Relation: Conference: International Conference on Sustainable Automotive ...

  11. Chemical Kinetic Research on HCCI & Diesel Fuels | Department of Energy

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

    Chemical Kinetic Research on HCCI & Diesel Fuels Chemical Kinetic Research on HCCI & Diesel Fuels 2009 DOE Hydrogen Program and Vehicle Technologies Program Annual Merit Review and Peer Evaluation Meeting, May 18-22, 2009 -- Washington D.C. ace_13_pitz.pdf (1.42 MB) More Documents & Publications Multidimensional simulation and chemical kinetics development for high efficiency clean combustion engines Chemical Kinetic Research on HCCI & Diesel Fuels Vehicle Technologies Office

  12. RESOLUTION OF URANIUM ISOTOPES WITH KINETIC PHOSPHORESCENCE ANALYSIS

    SciTech Connect (OSTI)

    Miley, Sarah M.; Hylden, Anne T.; Friese, Judah I.

    2013-04-01

    This study was conducted to test the ability of the Chemchek™ Kinetic Phosphorescence Analyzer Model KPA-11 with an auto-sampler to resolve the difference in phosphorescent decay rates of several different uranium isotopes, and therefore identify the uranium isotope ratios present in a sample. Kinetic phosphorescence analysis (KPA) is a technique that provides rapid, accurate, and precise determination of uranium concentration in aqueous solutions. Utilizing a pulsed-laser source to excite an aqueous solution of uranium, this technique measures the phosphorescent emission intensity over time to determine the phosphorescence decay profile. The phosphorescence intensity at the onset of decay is proportional to the uranium concentration in the sample. Calibration with uranium standards results in the accurate determination of actual concentration of the sample. Different isotopes of uranium, however, have unique properties which should result in different phosphorescence decay rates seen via KPA. Results show that a KPA is capable of resolving uranium isotopes.

  13. Systems engineering analysis of kinetic energy weapon concepts

    SciTech Connect (OSTI)

    Senglaub, M.

    1996-06-01

    This study examines, from a systems engineering design perspective, the potential of kinetic energy weapons being used in the role of a conventional strategic weapon. Within the Department of Energy (DOE) complex, strategic weapon experience falls predominantly in the nuclear weapons arena. The techniques developed over the years may not be the most suitable methodologies for use in a new design/development arena. For this reason a more fundamental approach was pursued with the objective of developing an information base from which design decisions might be made concerning the conventional strategic weapon system concepts. The study examined (1) a number of generic missions, (2) the effects of a number of damage mechanisms from a physics perspective, (3) measures of effectiveness (MOE`s), and (4) a design envelope for kinetic energy weapon concepts. With the base of information a cut at developing a set of high-level system requirements was made, and a number of concepts were assessed against these requirements.

  14. Simulation of the kinetics of precipitation reactions in ferritic steels

    SciTech Connect (OSTI)

    Schneider, A. . E-mail: schneider@mpie.de; Inden, G.

    2005-01-10

    Computer simulations of diffusion-controlled phase transformations in model alloys of Fe-Cr-C, Fe-Cr-W-C, Fe-Cr-Si-C, and Fe-Cr-Co-V-C are presented. The compositions considered are typical for ferritic steels. The simulations are performed using the software DICTRA and the thermodynamic calculations of phase equilibria are performed using Thermo-Calc. The thermodynamic driving forces and the kinetics of diffusion-controlled precipitation reactions of M{sub 23}C{sub 6}, M{sub 7}C{sub 3}, cementite and Laves-phase (Fe, Cr){sub 2}W are discussed. The simultaneous growth of stable and metastable phases is treated in a multi-cell approach. The results show remarkable effects on the growth kinetics due to the competition during simultaneous growth.

  15. PROTON KINETIC EFFECTS IN VLASOV AND SOLAR WIND TURBULENCE

    SciTech Connect (OSTI)

    Servidio, S.; Valentini, F.; Perrone, D.; Veltri, P.; Osman, K. T.; Chapman, S.; Califano, F.; Matthaeus, W. H.

    2014-02-01

    Kinetic plasma processes are investigated in the framework of solar wind turbulence, employing hybrid Vlasov-Maxwell (HVM) simulations. Statistical analysis of spacecraft observation data relates proton temperature anisotropy T /T {sub ∥} and parallel plasma beta β{sub ∥}, where subscripts refer to the ambient magnetic field direction. Here, this relationship is recovered using an ensemble of HVM simulations. By varying plasma parameters, such as plasma beta and fluctuation level, the simulations explore distinct regions of the parameter space given by T /T {sub ∥} and β{sub ∥}, similar to solar wind sub-datasets. Moreover, both simulation and solar wind data suggest that temperature anisotropy is not only associated with magnetic intermittent events, but also with gradient-type structures in the flow and in the density. This connection between non-Maxwellian kinetic effects and various types of intermittency may be a key point for understanding the complex nature of plasma turbulence.

  16. Complexity reduction of collisional-radiative kinetics for atomic plasma

    SciTech Connect (OSTI)

    Le, Hai P.; Karagozian, Ann R.; Cambier, Jean-Luc

    2013-12-15

    Thermal non-equilibrium processes in partially ionized plasmas can be most accurately modeled by collisional-radiative kinetics. This level of detail is required for an accurate prediction of the plasma. However, the resultant system of equations can be prohibitively large, making multi-dimensional and unsteady simulations of non-equilibrium radiating plasma particularly challenging. In this paper, we present a scheme for model reduction of the collisional-radiative kinetics, by combining energy levels into groups and deriving the corresponding macroscopic rates for all transitions. Although level-grouping is a standard approach to this type of problem, we provide here a mechanism for achieving higher-order accuracy by accounting for the level distribution within a group. The accuracy and benefits of the scheme are demonstrated for the generic case of atomic hydrogen by comparison with the complete solution of the master rate equations and other methods.

  17. On consistent kinetic and derivative interactions for gravitons

    SciTech Connect (OSTI)

    Noller, Johannes

    2015-04-17

    The only known fully ghost-free and consistent Lorentz-invariant kinetic term for a graviton (or indeed for any spin-2 field) is the Einstein-Hilbert term. Here we propose and investigate a new candidate family of kinetic interactions and their extensions to derivative interactions involving several spin-2 fields. These new terms generically break diffeomorphism invariance(s) and as a result can lead to the propagation of 5 degrees of freedom for a single spin-2 field — analogous to ghost-free Massive Gravity. We discuss under what circumstances these new terms can be used to build healthy effective field theories and in the process establish the ‘Jordan’ and ‘Einstein’ frame pictures for Massive-, Bi- and Multi-Gravity.

  18. Elucidating the Complex Recombination Kinetics in Organic-Inorganic

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

    Trihalide Perovskites* | MIT-Harvard Center for Excitonics Elucidating the Complex Recombination Kinetics in Organic-Inorganic Trihalide Perovskites* December 8, 2015 at 4:30pm/36-428 Dane de Quilettes University of Washington deQuilettes-2 Solution processed semiconductors are often plagued by performance limiting defects, surprisingly organometal trihalide perovskites (e.g. CH3NH3PbI3) have exhibited excellent photovoltaic power conversion efficiencies comparable to meticulously refined

  19. Chemical Kinetic Research on HCCI & Diesel Fuels

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

    Laboratory Chemical Kinetic Research on HCCI & Diesel Fuels William J. Pitz (PI), Charles K. Westbrook, Marco Mehl, M. Lee Davisson Lawrence Livermore National Laboratory May 12, 2009 DOE National Laboratory Advanced Combustion Engine R&D Merit Review and Peer Evaluation Washington, DC This presentation does not contain any proprietary or confidential information This work performed under the auspices of the U.S. Department of Energy by Lawrence Livermore National Laboratory under

  20. Kinetics, Mechanics and Microstructure Changes in Storage Media

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

    Focus Session on Hydrogen Storage DOE Hydrogen Program Review Crystal Gateway Marriott, Crystal City, VA May 18, 2006 Kinetics, Mechanics and Microstructure Changes in Storage Media Anter El-Azab Tel: 850-410-6655, E-mail address: anter@eng.fsu.edu Materials Theory Group School of Computational science and Mechanical Engineering Department Florida State University Tallahassee, FL 32310 Florida State University Materials Theory Group Objective The objective of this talk is to expose a number of

  1. Deflection by kinetic impact: Sensitivity to asteroid properties

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Bruck Syal, Megan; Michael Owen, J.; Miller, Paul L.

    2016-05-01

    Impacting an asteroid with a spacecraft traveling at high speed delivers an impulsive change in velocity to the body. In certain circumstances, this strategy could be used to deflect a hazardous asteroid, moving its orbital path off of an Earth-impacting course. However, the efficacy of momentum delivery to asteroids by hypervelocity impact is sensitive to both the impact conditions (particularly velocity) and specific characteristics of the target asteroid. We numerically model asteroid response to kinetic impactors under a wide range of initial conditions, using an Adaptive Smoothed Particle Hydrodynamics code. Impact velocities spanning 1–30 km/s were investigated, yielding, for amore » particular set of assumptions about the modeled target material, a power-law dependence consistent with a velocity-scaling exponent of μ = 0.44. Target characteristics including equation of state, strength model, porosity, rotational state, and shape were varied, and corresponding changes in asteroid response were documented. Moreover, the kinetic-impact momentum-multiplication factor, β, decreases with increasing asteroid cohesion and increasing porosity. Although increased porosity lowers β, larger porosities result in greater deflection velocities, as a consequence of reduced target masses for asteroids of fixed size. Porosity also lowers disruption risk for kinetic impacts near the threshold of disruption. Including fast (P = 2.5 h) and very fast (P = 100 s) rotation did not significantly alter β but did affect the risk of disruption by the impact event. Asteroid shape is found to influence the efficiency of momentum delivery, as local slope conditions can change the orientation of the crater ejecta momentum vector. Our results emphasize the need for asteroid characterization studies to bracket the range of target conditions expected at near-Earth asteroids while also highlighting some of the principal uncertainties associated with the kinetic-impact deflection

  2. Kinetic Simulations of Fusion Energy Dynamics at the Extreme Scale |

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

    Argonne Leadership Computing Facility Kinetic Simulations of Fusion Energy Dynamics at the Extreme Scale PI Name: William Tang PI Email: tang@pppl.gov Institution: Princeton Plasma Physics Laboratory Allocation Program: INCITE Allocation Hours at ALCF: 40 Million Year: 2013 Research Domain: Physics To build the scientific foundations needed to develop fusion power as a clean and sustainable energy source, the timely development of a high-physics-fidelity predictive simulation capability for

  3. TOTAL SES EJ/EK EN V EN IV EN III

    National Nuclear Security Administration (NNSA)

    EJEK EN V EN IV EN III NN (Engineering) NQ (ProfTechAdmin) NU (TechAdmin Support) ELIGIBLE TO RETIRE IMMEDIATELY 9 11.8% ELIGIBLE TO RETIRE BY 3272014 23 30.3% Males 50 65.8%...

  4. Kinetic and reactor models for HDT of middle distillates

    SciTech Connect (OSTI)

    Cotta, R.M.; Filho, R.M.

    1996-12-31

    Hydrodesulfurization (HDS) and hydrodenitrogenation (HDN) of middle distillates over a commercial Ni-Mo/y-Al{sub 2}O{sub 3} has been studied under wide operating conditions just as 340 to 380{degrees}C and 38 to 98 atm. A Power Law model was presented to each one of those reactions. The parameters of kinetic equations were estimated solving the ordinary differential equations by the 4 order Runge-Kutta-Gill algorithm and Marquardt method for searching of set of kinetic parameters (kinetic constants as well as the orders of reactions). An adiabatic diesel hydrotreating trickle-bed reactor packed with the same catalyst was simulated numerically in order to check up the behavior of this specific reaction system. One dimensional pseudo-homogeneous model was used in this work. For each feed, the mass and energy balance equations were integrated along the length of the catalytic bed using the 4th Runge-Kutta-Gill method. The performance of two industrial reactors was checked. 5 refs., 2 tabs.

  5. Effect of morphology of hydrophobic surfaces on cavitation kinetics

    SciTech Connect (OSTI)

    LUZAR,ALENKA; LEUNG,KEVIN

    2000-04-24

    Cavitation has been suggested to be a possible source of long range interactions between mesoscopic hydrophobic surfaces. While evaporation is predicted by thermodynamics, little is known about its kinetics. Glauber dynamics Monte Carlo simulations of a lattice gas close to liquid-gas coexistence and confined between partially drying surfaces are used to model the effect of water confinement on the dynamics of surface-induced phase transition. Specifically, they examine how kinetics of induced evaporation change as the texture of hydrophobic surfaces is varied. Evaporation rates are considerably slowed with relatively small amount of hydrophilic coverage. However, the distribution of hydrophilic patches is found to be crucial, with the homogeneous one being much more effective in slowing the formation of vapor tubes which triggers the evaporation process. They estimate the free energy barrier of vapor tube formation via transition state theory, using a constrained forward-backward umbrella sampling technique applied to the metastable, confined liquid. Furthermore, to relate simulation rates to experimental ones, they perform simulations using the mass-conserving Kawasaki algorithm. They predict evaporation time scales that range from hundreds of picoseconds in the case of mesoscopic surfaces {approximately} 10{sup 4} nm{sup 2} to tens of nanoseconds for smaller surfaces {approximately} 40 nm{sup 2}, when the two surfaces are {approximately} 10 solvent layers apart. The present study demonstrates that cavitation is kinetically viable in real systems and should be considered in studies of processes at confined geometry.

  6. Kinetic temperatures of heavy ions in the solar wind

    SciTech Connect (OSTI)

    Bochsler, P.; Geiss, J.; Joos, R.

    1990-11-01

    From a refined analysis of 4 years of data of the ion composition instrument on board ISEE 3 we find that in the overwhelming majority of observations kinetic temperatures of ions are approximately proportional to their masses. The logarithmic average for T(/sup 4/He/sup + +/) is 5.363; for T(O/sup 6 +/) and T(O/sup 7 +/) it is 5.978 and 6.000, respectively, corresponding to T(O)/T(He) = 4.2. For we find 6.52, corresponding to T(Fe)/T(He) = 14. The correlation coefficients between oxygen and helium kinetic temperatures are high (approx.0.78 or above), whereas for the correlation log T(Fe) versus log T(He) we find a value of only 0.44 due to the large measurement uncertainties of T(He). Significant deviations from the mass/temperature proportionality are found at occasions of cool and dense solar wind flow when Coulomb collisions succeed to equilibrate kinetic temperatures of different ions species.

  7. Accelerating quantum instanton calculations of the kinetic isotope effects

    SciTech Connect (OSTI)

    Karandashev, Konstantin; Vaníček, Jiří

    2015-11-21

    Path integral implementation of the quantum instanton approximation currently belongs among the most accurate methods for computing quantum rate constants and kinetic isotope effects, but its use has been limited due to the rather high computational cost. Here, we demonstrate that the efficiency of quantum instanton calculations of the kinetic isotope effects can be increased by orders of magnitude by combining two approaches: The convergence to the quantum limit is accelerated by employing high-order path integral factorizations of the Boltzmann operator, while the statistical convergence is improved by implementing virial estimators for relevant quantities. After deriving several new virial estimators for the high-order factorization and evaluating the resulting increase in efficiency, using ⋅H{sub α} + H{sub β}H{sub γ} → H{sub α}H{sub β} + ⋅ H{sub γ} reaction as an example, we apply the proposed method to obtain several kinetic isotope effects on CH{sub 4} + ⋅ H ⇌ ⋅ CH{sub 3} + H{sub 2} forward and backward reactions.

  8. NO sub x -char reactions: Kinetics and transport aspects

    SciTech Connect (OSTI)

    Calo, J.M.; Suuberg, E.M.

    1990-01-01

    The present project is motivated by the need to reduce NO{sub x} emissions from combustors, especially coal combustors. Reactions with carbon are known to be effective at reducing No to N{sub 2}, and remain interesting candidates in a wide variety of possible applications. These reactions are known to be important in reducing NO{sub x} emissions from fluidized bed coal combustors, in which the coal char itself serves as the reducing agent. The principal goal of this project is to develop a mechanistic understanding of the processes by which carbons reduce NO to N{sub 2}. The carbon was a char derived from phenol-formaldehyde resin. This material has been noted to be a reasonable model for coal chars in most respects, expect that its gasification behavior is not complicated by catalytic processes due to minerals. In the first phases of the project, the global kinetics of the process were established. In more recent work, attention has been turned to the individual steps in the mechanism. Recent quarterly reports have detailed the role of both chemisorption and desorption processes in determining the course and kinetics of the process. This report continues the reporting of results obtained along these lines, and draws an important new conclusion concerning the number of separate processes involved in determining the kinetics. 40 refs., 3 figs., 2 tabs.

  9. Kinetic theory of nonlinear transport phenomena in complex plasmas

    SciTech Connect (OSTI)

    Mishra, S. K. [Institute for Plasma Research (IPR), Gandhinagar 382428 (India); Sodha, M. S. [Centre for Energy Studies (CES), Indian Institute of Technology Delhi (IITD), New Delhi 110016 (India)

    2013-03-15

    In contrast to the prevalent use of the phenomenological theory of transport phenomena, a number of transport properties of complex plasmas have been evaluated by using appropriate expressions, available from the kinetic theory, which are based on Boltzmann's transfer equation; in particular, the energy dependence of the electron collision frequency has been taken into account. Following the recent trend, the number and energy balance of all the constituents of the complex plasma and the charge balance on the particles is accounted for; the Ohmic loss has also been included in the energy balance of the electrons. The charging kinetics for the complex plasma comprising of uniformly dispersed dust particles, characterized by (i) uniform size and (ii) the Mathis, Rumpl, and Nordsieck power law of size distribution has been developed. Using appropriate expressions for the transport parameters based on the kinetic theory, the system of equations has been solved to investigate the parametric dependence of the complex plasma transport properties on the applied electric field and other plasma parameters; the results are graphically illustrated.

  10. A Pore Scale Evaluation of the Kinetics of Mineral Dissolution and Precipitation Reactions (EMSI)

    SciTech Connect (OSTI)

    Steefel, Carl I.

    2006-06-01

    The chief goals for CEKA are to (1) collect and synthesize molecular-level kinetic data into a coherent framework that can be used to predict time evolution of environmental processes over a range of temporal and spatial scales; (2) train a cohort of talented and diverse students to work on kinetic problems at multiple scales; (3) develop and promote the use of new experimental techniques in environmental kinetics; (4) develop and promote the use of new modeling tools to conceptualize reaction kinetics in environmental systems; and (5) communicate our understanding of issues related to environmental kinetics and issues of scale to the broader scientific community and to the public.

  11. LOW-LEVEL RADIOACTIVE & MIXED WASTE SHIPMENTS TO THE NEVADA NATIONAL SECURITY SITE

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

    NV NY NY NV OH TN TN TN, WA, CA TN TN TN TX y ct 2 Plant Perma-Fix LOW-LEVEL RADIOACTIVE & MIXED WASTE SHIPMENTS TO THE NEVADA NATIONAL SECURITY SITE FIRST QUARTER REPORT, FY 2011 (OCTOBER, NOVEMBER, DECEMBER 2010) Livermore National Laboratory ergy Alliance onal Laboratory Mixed Waste Treatment Project gonne National Laboratory ational Laboratory Gaseous Diffusion Plant Proving Ground terra, LLC en National Laboratory y Environmental Services ecurity Technologies, Inc. h Gaseous Diffusion

  12. KINETICS OF SLURRY PHASE FISCHER-TROPSCH SYSTHESIS

    SciTech Connect (OSTI)

    Dragomir B. Bukur; Gilbert F. Froment; Tomasz Olewski

    2005-09-29

    This report covers the third year of this research grant under the University Coal Research program. The overall objective of this project is to develop a comprehensive kinetic model for slurry phase Fischer-Tropsch synthesis (FTS) on iron catalysts. This model will be validated with experimental data obtained in a stirred tank slurry reactor (STSR) over a wide range of process conditions. The model will be able to predict molar flow rates and concentrations of all reactants and major product species (H{sub 2}O, CO{sub 2}, linear 1- and 2-olefins, and linear paraffins) as a function of reaction conditions in the STSR. During the reporting period we utilized experimental data from the STSR, that were obtained during the first two years of the project, to perform vapor-liquid equilibrium (VLE) calculations and estimate kinetic parameters. We used a modified Peng-Robinson (PR) equation of state (EOS) with estimated values of binary interaction coefficients for the VLE calculations. Calculated vapor phase compositions were in excellent agreement with experimental values from the STSR under reaction conditions. Occasional discrepancies (for some of the experimental data) between calculated and experimental values of the liquid phase composition were ascribed to experimental errors. The VLE calculations show that the vapor and the liquid are in thermodynamic equilibrium under reaction conditions. Also, we have successfully applied the Levenberg-Marquardt method (Marquardt, 1963) to estimate parameters of a kinetic model proposed earlier by Lox and Froment (1993b) for FTS on an iron catalyst. This kinetic model is well suited for initial studies where the main goal is to learn techniques for parameter estimation and statistical analysis of estimated values of model parameters. It predicts that the chain growth parameter ({alpha}) and olefin to paraffin ratio are independent of carbon number, whereas our experimental data show that they vary with the carbon number

  13. Kinetics and mechanisms of reactions involving small aromatic reactive intermediates

    SciTech Connect (OSTI)

    Lin, M.C.

    1993-12-01

    Small aromatic radicals such as C{sub 6}H{sub 5}, C{sub 6}H{sub 5}O and C{sub 6}H{sub 4} are key prototype species of their homologs. C{sub 6}H{sub 5} and its oxidation product, C{sub 6}H{sub 5}O are believed to be important intermediates which play a pivotal role in hydrocarbon combustion, particularly with regard to soot formation. Despite their fundamental importance, experimental data on the reaction mechanisms and reactivities of these species are very limited. For C{sub 6}H{sub 5}, most kinetic data except its reactions with NO and NO{sub 2}, were obtained by relative rate measurements. For C{sub 6}H{sub 5}O, the authors have earlier measured its fragmentation reaction producing C{sub 5}H{sub 5} + CO in shock waves. For C{sub 6}H{sub 4}, the only rate constant measured in the gas phase is its recombination rate at room temperature. The authors have proposed to investigate systematically the kinetics and mechanisms of this important class of molecules using two parallel laser diagnostic techniques--laser resonance absorption (LRA) and resonance enhanced multiphoton ionization mass spectrometry (REMPI/MS). In the past two years, study has been focused on the development of a new multipass adsorption technique--the {open_quotes}cavity-ring-down{close_quotes} technique for kinetic applications. The preliminary results of this study appear to be quite good and the sensitivity of the technique is at least comparable to that of the laser-induced fluorescence method.

  14. Kinetic Theory of Plasma Waves - Part I: Introduction

    SciTech Connect (OSTI)

    Lamalle, P.U

    2004-03-15

    The kinetic description of linear waves in plasmas is succinctly presented, with emphasis on applications to high-frequency (hf) wave heating and current drive. The Maxwell-Vlasov system of equations is introduced. Its two-timescale analysis yields the linearized Vlasov and the quasilinear Fokker-Planck equations. The standard guiding centre and Hamiltonian formalisms are presented. Two formulations of the hf plasma wave equation are given: as a partial differential equation to hold at each position, and as a global Galerkin ('variational') form.

  15. Evaluation of kinetic phosphorescence analysis for the determination of uranium

    SciTech Connect (OSTI)

    Croatto, P.V.; Frank, I.W.; Johnson, K.D.; Mason, P.B.; Smith, M.M.

    1997-12-01

    In the past, New Brunswick Laboratory (NBL) has used a fluorometric method for the determination of sub-microgram quantities of uranium. In its continuing effort to upgrade and improve measurement technology, NBL has evaluated the commercially-available KPA-11 kinetic phosphorescence analyzer (Chemchek, Richland, WA). The Chemchek KPA-11 is a bench-top instrument which performs single-measurement, quench-corrected analyses for trace uranium. It incorporates patented kinetic phosphorimetry techniques to measure and analyze sample phosphorescence as a function of time. With laser excitation and time-corrected photon counting, the KPA-11 has a lower detection limit than conventional fluorometric methods. Operated with a personal computer, the state-of-the-art KPA-11 offers extensive time resolution and phosphorescence lifetime capabilities for additional specificity. Interferences are thereby avoided while obtaining precise measurements. Routine analyses can be easily and effectively accomplished, with the accuracy and precision equivalent to the pulsed-laser fluorometric method presently performed at NBL, without the need for internal standards. Applications of kinetic phosphorimetry at NBL include the measurement of trace level uranium in retention tank, waste samples, and low-level samples. It has also been used to support other experimental activities at NBL by the measuring of nanogram amounts of uranium contamination (in blanks) in isotopic sample preparations, and the determining of elution curves of different ion exchange resins used for uranium purification. In many cases, no pretreatment of samples was necessary except to fume them with nitric acid, and then to redissolve and dilute them to an appropriate concentration with 1 M HNO{sub 3} before measurement. Concentrations were determined on a mass basis ({micro}g U/g of solution), but no density corrections were needed since all the samples (including the samples used for calibration) were in the same

  16. Bio-butanol: Combustion properties and detailed chemical kinetic model

    SciTech Connect (OSTI)

    Black, G.; Curran, H.J.; Pichon, S.; Simmie, J.M.; Zhukov, V.

    2010-02-15

    Autoignition delay time measurements were performed at equivalence ratios of 0.5, 1 and 2 for butan-1-ol at reflected shock pressures of 1, 2.6 and 8 atm at temperatures from 1100 to 1800 K. High-level ab initio calculations were used to determine enthalpies of formation and consequently bond dissociation energies for each bond in the alcohol. A detailed chemical kinetic model consisting of 1399 reactions involving 234 species was constructed and tested against the delay times and also against recent jet-stirred reactor speciation data with encouraging results. The importance of enol chemistry is highlighted. (author)

  17. Thermodynamic and kinetic control of the lateral Si wire growth

    SciTech Connect (OSTI)

    Dedyulin, Sergey N. Goncharova, Lyudmila V.

    2014-03-24

    Reproducible lateral Si wire growth has been realized on the Si (100) surface. In this paper, we present experimental evidence showing the unique role that carbon plays in initiating lateral growth of Si wires on a Si (100) substrate. Once initiated in the presence of ?5 ML of C, lateral growth can be achieved in the range of temperatures, T?=?450650?C, and further controlled by the interplay of the flux of incoming Si atoms with the size and areal density of Au droplets. Critical thermodynamic and kinetic aspects of the growth are discussed in detail.

  18. Non-minimal Kinetic coupling to gravity and accelerated expansion

    SciTech Connect (OSTI)

    Granda, L.N.

    2010-07-01

    We study a scalar field with kinetic term coupled to itself and to the curvature, as a source of dark energy, and analyze the role of this new coupling in the accelerated expansion at large times. In the case of scalar field dominance, the scalar field and potential giving rise to power-law expansion are found in some cases, and a dynamical equation of state is calculated for a given solution of the field equations. A behavior very close to that of the cosmological constant was found.

  19. Convergent synthesis of proteins by kinetically controlled ligation

    DOE Patents [OSTI]

    Kent, Stephen; Pentelute, Brad; Bang, Duhee; Johnson, Erik; Durek, Thomas

    2010-03-09

    The present invention concerns methods and compositions for synthesizing a polypeptide using kinetically controlled reactions involving fragments of the polypeptide for a fully convergent process. In more specific embodiments, a ligation involves reacting a first peptide having a protected cysteyl group at its N-terminal and a phenylthioester at its C-terminal with a second peptide having a cysteine residue at its N-termini and a thioester at its C-termini to form a ligation product. Subsequent reactions may involve deprotecting the cysteyl group of the resulting ligation product and/or converting the thioester into a thiophenylester.

  20. Chemical Kinetics in Support of Syngas Turbine Combustion

    SciTech Connect (OSTI)

    Dryer, Frederick

    2007-07-31

    This document is the final report on an overall program formulated to extend our prior work in developing and validating kinetic models for the CO/hydrogen/oxygen reaction by carefully analyzing the individual and interactive behavior of specific elementary and subsets of elementary reactions at conditions of interest to syngas combustion in gas turbines. A summary of the tasks performed under this work are: 1. Determine experimentally the third body efficiencies in H+O{sub 2}+M = HO{sub 2}+M (R1) for CO{sub 2} and H{sub 2}O. 2. Using published literature data and the results in this program, further develop the present H{sub 2}/O{sub 2}/diluent and CO/H{sub 2}/O{sub 2}/diluent mechanisms for dilution with CO{sub 2}, H{sub 2}O and N{sub 2} through comparisons with new experimental validation targets for H{sub 2}-CO-O{sub 2}-N{sub 2} reaction kinetics in the presence of significant diluent fractions of CO{sub 2} and/or H{sub 2}O, at high pressures. (task amplified to especially address ignition delay issues, see below). 3. Analyze and demonstrate issues related to NOx interactions with syngas combustion chemistry (task amplified to include interactions of iron pentacarbonyl with syngas combustion chemistry, see below). 4. Publish results, including updated syngas kinetic model. Results are summarized in this document and its appendices. Three archival papers which contain a majority of the research results have appeared. Those results not published elsewhere are highlighted here, and will appear as part of future publications. Portions of the work appearing in the above publications were also supported in part by the Department of Energy under Grant No. DE-FG02-86ER-13503. As a result of and during the research under the present contract, we became aware of other reported results that revealed substantial differences between experimental characterizations of ignition delays for syngas mixtures and ignition delay predictions based upon homogenous kinetic modeling. We

  1. Kinetics and mechanisms of NO{sub x}: Char reduction

    SciTech Connect (OSTI)

    Suuberg, E.M.; Lilly, W.D.; Aarna, I.

    1996-09-01

    This report conveys recent progress on two issues. The first concerns the prediction on char-NO reactivity in general. The work has been performed upon a literature review, supplemented by our own recent results. The second part has to do with more detailed issues related to the mechanism of the reaction. Specifically, it is concerned with how oxide desorption can affect the observed kinetics. The report is divided into two stand-alone sections, on each of the above two topics. This material recently served as a basis for two manuscripts prepared for presentation at an American Chemical Society National meeting.

  2. En Neo | Open Energy Information

    Open Energy Info (EERE)

    of services includes development, planning, construction and operation of wind power plants and photovoltaic plants. References: En-Neo1 This article is a stub. You can help...

  3. Solar kinetics` photovoltaic concentrator module and tracker development

    SciTech Connect (OSTI)

    White, D.L.; Howell, B. [Solar Kinetics, Inc., Dallas, TX (United States)

    1995-11-01

    Solar Kinetics, Inc., has been developing a point-focus concentrating photovoltaic module and tracker system under contract to Sandia National Laboratories. The primary focus of the contract was to achieve a module design that was manufacturable and passed Sandia`s environmental testing. Nine modules of two variations were assembled, tested, and characterized in Phase 1, and results of these tests were promising, with module efficiency approaching the theoretical limit achievable with the components used. The module efficiency was 11.9% at a solar irradiance of 850 W/m{sup 2} and an extrapolated cell temperature of 25{degrees}C. Improvements in module performance are anticipated as cell efficiencies meet their expectations. A 2-kW tracker and controller accommodating 20 modules was designed, built, installed, and operated at Solar Kinetics` test site. The drive used many commercially available components in an innovative arrangement to reduce cost and increase reliability. Backlash and bearing play were controlled by use of preloaded, low slip-stick, synthetic slide bearings. The controller design used a standard industrial programmable logic controller to perform ephemeris calculations, operate the actuators, and monitor encoders.

  4. Single Molecule Kinetics of ENTH Binding to Lipid Membranes

    SciTech Connect (OSTI)

    Rozovsky, Sharon; Forstner, Martin B.; Sondermann, Holger; Groves, Jay T.

    2012-04-03

    Transient recruitment of proteins to membranes is a fundamental mechanism by which the cell exerts spatial and temporal control over proteins’ localization and interactions. Thus, the specificity and the kinetics of peripheral proteins’ membrane residence are an attribute of their function. In this article, we describe the membrane interactions of the interfacial epsin N-terminal homology (ENTH) domain with its target lipid phosphatidylinositol (4,5)-bisphosphate (PtdIns(4,5)P2). The direct visualization and quantification of interactions of single ENTH molecules with supported lipid bilayers is achieved using total internal reflection fluorescence microscopy (TIRFM) with a time resolution of 13 ms. This enables the recording of the kinetic behavior of ENTH interacting with membranes with physiologically relevant concentrations of PtdIns(4,5)P2 despite the low effective binding affinity. Subsequent single fluorophore tracking permits us to build up distributions of residence times and to measure ENTH dissociation rates as a function of membrane composition. In addition, due to the high time resolution, we are able to resolve details of the motion of ENTH associated with a simple, homogeneous membrane. In this case ENTH’s diffusive transport appears to be the result of at least three different diffusion processes.

  5. The kinetic energy interceptor: Shooting a bullet with a bullet

    SciTech Connect (OSTI)

    1995-04-01

    Although the Cold War has ended, the threat of proliferation with chemical, biological, and nuclear warheads continues. Two factors further increase the threat from these weapons of mass destruction: knowledge of missile technology has spread extensively, and, in recent years, many countries - some of them unfriendly to the US and its allies - have obtained short- and intermediate-range missiles. The threat posed by such missiles was amply demonstrated during the Gulf War. Thus, the need to protect US and allied forces from these weapons has never been greater. When nuclear-tipped defensive missiles, such as Sprint and Spartan, were phased out years ago, the US turned for its defense to kinetic-energy {open_quotes}kill{close_quotes} interceptors - missiles that destroy an enemy missile by striking it with lethal force and accuracy at some point in its trajectory. The Patriot missile is probably the best-known kinetic-energy (KE) interceptor in the US defensive arsenal. To counter the spreading threat of proliferation, LLNL and other laboratories have been participating in a joint program funded by the Ballistic Missile Defense Organization (BMDO), within the Department of Defense, to develop defensive missile systems. Participants are designing, testing, and certifying KE interceptors to defend against current and future missile threats. These research efforts are described.

  6. Adding kinetics and hydrodynamics to the CHEETAH thermochemical code

    SciTech Connect (OSTI)

    Fried, L.E., Howard, W.M., Souers, P.C.

    1997-01-15

    In FY96 we released CHEETAH 1.40, which made extensive improvements on the stability and user friendliness of the code. CHEETAH now has over 175 users in government, academia, and industry. Efforts have also been focused on adding new advanced features to CHEETAH 2.0, which is scheduled for release in FY97. We have added a new chemical kinetics capability to CHEETAH. In the past, CHEETAH assumed complete thermodynamic equilibrium and independence of time. The addition of a chemical kinetic framework will allow for modeling of time-dependent phenomena, such as partial combustion and detonation in composite explosives with large reaction zones. We have implemented a Wood-Kirkwood detonation framework in CHEETAH, which allows for the treatment of nonideal detonations and explosive failure. A second major effort in the project this year has been linking CHEETAH to hydrodynamic codes to yield an improved HE product equation of state. We have linked CHEETAH to 1- and 2-D hydrodynamic codes, and have compared the code to experimental data. 15 refs., 13 figs., 1 tab.

  7. Kinetics and deactivation of sulfated zirconia catalysts for butane isomerization

    SciTech Connect (OSTI)

    Fogash, K.B.; Larson, R.B.; Gonzalez, M.R.

    1996-09-15

    Reaction kinetics studies were conducted of n-butane and isobutane isomerization over sulfated zirconia at 423 K. The kinetic data can be described well by a rate expression based on a reversible, bimolecular surface reaction between two adsorbed n-C{sub 4} species, probably through a C{sub 8} intermediate, to produce one i-C{sub 4} species, as well as surface reaction between two adsorbed i-C{sub 4} species to produce one n-C{sub 4} species. This reaction sequence also describes well the rates of C{sub 4}-disproportionation reactions to produce C{sub 3} and C{sub 5} species. The initial rate of catalyst deactivation is faster during n-butane isomerization than during isobutane isomerization, and the longer-term rate of deactivation during n-butane isomerization increases with the pressures of n-butane. The more rapid catalyst deactivation during n-butane isomerization may be related to the formation of n-C{sub 4}-diene species. 25 refs., 10 figs., 4 tabs.

  8. Kinetic neoclassical transport in the H-mode pedestal

    SciTech Connect (OSTI)

    Battaglia, D. J.; Chang, C. S.; Ku, S.; Grierson, B. A.; Burrell, K. H.; Grassie, J. S. de

    2014-07-15

    Multi-species kinetic neoclassical transport through the QH-mode pedestal and scrape-off layer on DIII-D is calculated using XGC0, a 5D full-f particle-in-cell drift-kinetic solver with self-consistent neutral recycling and sheath potentials. Quantitative agreement between the flux-driven simulation and the experimental electron density, impurity density, and orthogonal measurements of impurity temperature and flow profiles is achieved by adding random-walk particle diffusion to the guiding-center drift motion. The radial electric field (E{sub r}) that maintains ambipolar transport across flux surfaces and to the wall is computed self-consistently on closed and open magnetic field lines and is in excellent agreement with experiment. The E{sub r} inside the separatrix is the unique solution that balances the outward flux of thermal tail deuterium ions against the outward neoclassical electron flux and inward pinch of impurity and colder deuterium ions. Particle transport in the pedestal is primarily due to anomalous transport, while the ion heat and momentum transport are primarily due to the neoclassical transport. The full-f treatment quantifies the non-Maxwellian energy distributions that describe a number of experimental observations in low-collisionallity pedestals on DIII-D, including intrinsic co-I{sub p} parallel flows in the pedestal, ion temperature anisotropy, and large impurity temperatures in the scrape-off layer.

  9. Development of Kinetic Mechanisms for Next-Generation Fuels and CFD Simulation of Advanced Combustion Engines

    SciTech Connect (OSTI)

    Pitz, William J.; McNenly, Matt J.; Whitesides, Russell; Mehl, Marco; Killingsworth, Nick J.; Westbrook, Charles K.

    2015-12-17

    Predictive chemical kinetic models are needed to represent next-generation fuel components and their mixtures with conventional gasoline and diesel fuels. These kinetic models will allow the prediction of the effect of alternative fuel blends in CFD simulations of advanced spark-ignition and compression-ignition engines. Enabled by kinetic models, CFD simulations can be used to optimize fuel formulations for advanced combustion engines so that maximum engine efficiency, fossil fuel displacement goals, and low pollutant emission goals can be achieved.

  10. A Comparison of HCCI Engine Performance Data and Kinetic Modeling Results

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

    over a Wide Rangeof Gasoline Range Surrogate Fuel Blends | Department of Energy A Comparison of HCCI Engine Performance Data and Kinetic Modeling Results over a Wide Rangeof Gasoline Range Surrogate Fuel Blends A Comparison of HCCI Engine Performance Data and Kinetic Modeling Results over a Wide Rangeof Gasoline Range Surrogate Fuel Blends Kinetic models of fuels are needed to allow the simulation of engine performance for research, design, or verification purposes. deer09_bunting.pdf

  11. Hydrolysis of late-washed, irradiated tetraphenylborate slurry simulants I: Phenylboric acid hydrolysis kinetics

    SciTech Connect (OSTI)

    Marek, J.C.

    2000-02-10

    The attached report details the kinetics of phenylboric acid reaction at 90 degrees C during precipitate hydrolysis processing of late-washed, irradiated tetraphenylborate slurry simulants.

  12. Gasdynamics in a coal seam. Part I: Mathematical description of the desorption kinetics

    SciTech Connect (OSTI)

    Kuznetsov, S.V.; Trofimov, V.A.

    2009-01-15

    The authors consider the gas desorption kinetics in the frame of a diffusion model, present alternative models and estimate their compatibility with the traditional.

  13. Structure and Kinetic Analysis of H[subscript 2]S Production...

    Office of Scientific and Technical Information (OSTI)

    of Hsubscript 2S Production by Human Mercaptopyruvate Sulfurtransferase Citation Details In-Document Search Title: Structure and Kinetic Analysis of Hsubscript 2S ...

  14. Shaping the composition profiles in heteroepitaxial quantum dots: Interplay of thermodynamic and kinetic effects

    SciTech Connect (OSTI)

    Georgiou, C.; Leontiou, T.; Kelires, P. C.

    2014-07-15

    Atomistic Monte Carlo simulations, coupling thermodynamic and kinetic effects, resolve a longstanding controversy regarding the origin of composition profiles in heteroepitaxial SiGe quantum dots. It is shown that profiles with cores rich in the unstrained (Si) component derive from near-equilibrium processes and intraisland diffusion. Profiles with cores rich in the strained (Ge) component are of nonequilibrium nature, i.e., they are strain driven but kinetically limited. They are shaped by the distribution of kinetic barriers of atomic diffusion in the islands. The diffusion pathways are clearly revealed for the first time. Geometrical kinetics play a minor role.

  15. KineticsFinal Report Cover Page Bakajin, O 59 BASIC BIOLOGICAL...

    Office of Scientific and Technical Information (OSTI)

    KineticsFinal Report Cover Page Bakajin, O 59 BASIC BIOLOGICAL SCIENCES; 42 ENGINEERING; CONSUMPTION RATES; DEAD TIME; DETECTION; DIFFUSION; DNA; ENERGY TRANSFER; FABRICATION;...

  16. Photoelectrochemical etching of epitaxial InGaN thin films: kinetics...

    Office of Scientific and Technical Information (OSTI)

    films: kinetics and nanostructuring. Abstract not provided. Authors: Xiao, Xiaoyin ; Fischer, Arthur J. ; Coltrin, Michael E. ; Lu, Ping ; Koleske, Daniel ; Wang, George T. ;...

  17. Isopiestic Kinetics of Powdered Pd/C/DPB Composite

    SciTech Connect (OSTI)

    Dinh, L; Saab, A

    2008-05-30

    In a 2006 LLNL internal report, a study of DEB and DPB based hydrogen getter materials was described. The materials, consisting of DEB or DPB physically blended with amorphous carbon on which palladium nanoparticle catalyst was supported, were studied during the course of reaction with fixed aliquots of hydrogen gas in order to observe their hydrogen consumption capacities as a function of ambient hydrogen pressure. The experiments demonstrated that the getter capacity was directly proportional to hydrogen fugacity: the lower the initial hydrogen pressure, the lower the resultant capacity at correspondingly low steady-state pressures. In the course of these experiments, further interesting observations were made of DEB and DPB reduction by hydrogen gas that painted a picture of a complicated reaction mechanism. To summarize, it was determined that reaction rate was controlled partly by diffusion of the organic diacetylene toward the catalyst surface. The results indicated this diffusion was in turn enhanced by phase changes in the course of the reaction that result in a liquid phase of the getter, and also by the heat of reaction, itself being proportional to initial reaction rate. However, these same two terms were speculated to have negative impacts on the net reaction kinetics, as well. It was suggested the liquid phase served to block gas access, and that excessively fast initial rates limited rate and capacity at later times by creating a depletion zone of reactant around the catalyst. Because of the nature of the experiments, whereby both hydrogen pressure and getter activity were changing in time, actual kinetic information could not be gathered. Knowledge of the reaction rate characteristics of these materials as a function of pressure and temperature is crucial to understanding the overall behavior of this material in service. Further, direct observation of the reaction rate can permit estimates of the diffusion of the reactive species. The present work

  18. Kinetics and Mechanisms of Calcite Reactions with Saline Waters

    SciTech Connect (OSTI)

    Gorman, Brian P

    2015-09-02

    Project Description: The general objective of the proposed research is to determine the kinetics and mechanisms of calcite reactions with saline waters over a wide range of saline water composition, pCO2, and modest ranges in T and P. This will be accomplished by studying both reaction rates and solubility from changes in solution chemistry, and making nanoscale observations of calcite precipitate surface morphology and composition at the micro-to-nano-scale to provide an understanding of controlling reaction mechanisms and pathways. The specific objectives necessary to reach the general objective are: a) determination of how pCO2, Ca2+, ionic strength and “foreign” ions influence reaction rates; and b) investigate the influence of these parameters on apparent kinetic solubility from dissolution and precipitation reactions. This information will clearly be central to the construction of reliable reaction-transport models to predict reservoir and formation response to increased CO2 in saline waters. This program was initially collaborative with John Morse at Texas A&M, however his passing shortly after the beginning of this program resulted in abbreviated research time and effort. Summary of Results: Early studies using electron microscopy and spectroscopy indicated that carbonate precipitation from natural seawater (NSW) conditions onto aragonite substrates was mediated by a surface amorphous calcium carbonate layer. It was hypothesized that this ACC layer (observed after < 5days reaction time) was responsible for the abnormal reaction kinetics and also served as a metastable seed layer for growth of epitaxial aragonite. Further studies of the ACC formation mechanism indicated a strong dependence on the Mg concentration in solution. Subsequent studies at shorter times (10 hrs) on calcite substrates and in a wide range of supersaturation conditions did not indicate any ACC layer. Instead, an epitaxial layer by layer

  19. On the nature of kinetic electrostatic electron nonlinear (KEEN) waves

    SciTech Connect (OSTI)

    Dodin, I. Y.; Fisch, N. J.

    2014-03-15

    An analytical theory is proposed for the kinetic electrostatic electron nonlinear (KEEN) waves originally found in simulations by Afeyan et al. [arXiv:1210.8105]. We suggest that KEEN waves represent saturated states of the negative mass instability (NMI) reported recently by Dodin et al. [Phys. Rev. Lett. 110, 215006 (2013)]. Due to the NMI, trapped electrons form macroparticles that produce field oscillations at harmonics of the bounce frequency. At large enough amplitudes, these harmonics can phase-lock to the main wave and form stable nonlinear dissipationless structures that are nonstationary but otherwise similar to Bernstein-Greene-Kruskal modes. The theory explains why the formation of KEEN modes is sensitive to the excitation scenario and yields estimates that agree with the numerical results of Afeyan et al. A new type of KEEN wave may be possible at even larger amplitudes of the driving field than those used in simulations so far.

  20. Mass independent kinetic energy reducing inlet system for vacuum environment

    DOE Patents [OSTI]

    Reilly, Peter T. A. [Knoxville, TN

    2010-12-14

    A particle inlet system comprises a first chamber having a limiting orifice for an incoming gas stream and a micrometer controlled expansion slit. Lateral components of the momentum of the particles are substantially cancelled due to symmetry of the configuration once the laminar flow converges at the expansion slit. The particles and flow into a second chamber, which is maintained at a lower pressure than the first chamber, and then moves into a third chamber including multipole guides for electromagnetically confining the particle. The vertical momentum of the particles descending through the center of the third chamber is minimized as an upward stream of gases reduces the downward momentum of the particles. The translational kinetic energy of the particles is near-zero irrespective of the mass of the particles at an exit opening of the third chamber, which may be advantageously employed to provide enhanced mass resolution in mass spectrometry.

  1. Mass independent kinetic energy reducing inlet system for vacuum environment

    DOE Patents [OSTI]

    Reilly, Peter T.A.

    2013-12-03

    A particle inlet system comprises a first chamber having a limiting orifice for an incoming gas stream and a micrometer controlled expansion slit. Lateral components of the momentum of the particles are substantially cancelled due to symmetry of the configuration once the laminar flow converges at the expansion slit. The particles and flow into a second chamber, which is maintained at a lower pressure than the first chamber, and then moves into a third chamber including multipole guides for electromagnetically confining the particle. The vertical momentum of the particles descending through the center of the third chamber is minimized as an upward stream of gases reduces the downward momentum of the particles. The translational kinetic energy of the particles is near-zero irrespective of the mass of the particles at an exit opening of the third chamber, which may be advantageously employed to provide enhanced mass resolution in mass spectrometry.

  2. Mass independent kinetic energy reducing inlet system for vacuum environment

    DOE Patents [OSTI]

    Reilly, Peter T.A.

    2014-05-13

    A particle inlet system comprises a first chamber having a limiting orifice for an incoming gas stream and a micrometer controlled expansion slit. Lateral components of the momentum of the particles are substantially cancelled due to symmetry of the configuration once the laminar flow converges at the expansion slit. The particles and flow into a second chamber, which is maintained at a lower pressure than the first chamber, and then moves into a third chamber including multipole guides for electromagnetically confining the particle. The vertical momentum of the particles descending through the center of the third chamber is minimized as an upward stream of gases reduces the downward momentum of the particles. The translational kinetic energy of the particles is near-zero irrespective of the mass of the particles at an exit opening of the third chamber, which may be advantageously employed to provide enhanced mass resolution in mass spectrometry.

  3. Structural characteristics and hydration kinetics of modified steel slag

    SciTech Connect (OSTI)

    Li Jianxin; Yu Qijun; Wei Jiangxiong Zhang Tongsheng

    2011-03-15

    This study investigates the structural characteristics and hydration kinetics of modified basic oxygen furnace steel slag. The basic oxygen furnace steel slag (BOFS) was mixed with electric arc furnace steel slag (EAFS) in appropriate ratios and heated again at high temperature in the laboratory. The mineralogical and structural characteristics of both BOFS and modified steel slag (MSS) were characterized by X-ray diffraction, optical microscopy, scanning electron microscopy, Raman and Fourier transform infrared spectroscopies. The results show that modification increases alite content in MSS and decreases alite crystal size with the formation of C{sub 6}AF{sub 2}. One more obvious heat evolution peak appears in MSS's heat-flow rate curves in comparison to BOFS, becoming similar to that of typical Portland cement paste. As a result, its cementitious activity is much improved.

  4. Chemical Kinetic Models for HCCI and Diesel Combustion

    SciTech Connect (OSTI)

    Pitz, W J; Westbook, C K; Mehl, M

    2008-10-30

    Hydrocarbon fuels for advanced combustion engines consist of complex mixtures of hundreds or even thousands of different components. These components can be grouped into a number of chemically distinct classes, consisting of n-paraffins, branched paraffins, cyclic paraffins, olefins, oxygenates, and aromatics. Biodiesel contains its own unique chemical class called methyl esters. The fractional amounts of these chemical classes are quite different in gasoline, diesel fuel, oil-sand derived fuels and bio-derived fuels, which contributes to the very different combustion characteristics of each of these types of combustion systems. The objectives of this project are: (1) Develop detailed chemical kinetic models for fuel components used in surrogate fuels for diesel and HCCI engines; (2) Develop surrogate fuel models to represent real fuels and model low temperature combustion strategies in HCCI and diesel engines that lead to low emissions and high efficiency; and (3) Characterize the role of fuel composition on low temperature combustion modes of advanced combustion engines.

  5. An efficient method for unfolding kinetic pressure driven VISAR data

    SciTech Connect (OSTI)

    Mark Harry Hess; Peterson, Kyle; Harvey-Thompson, Adam James

    2015-08-18

    Velocity Interferometer System for Any Reflector (VISAR) [Barker and Hollenbach, J. Appl. Phys. 43, 4669 (1972)] is a well-known diagnostic that is employed on many shock physics and pulsed-power experiments. With the VISAR diagnostic, the velocity on the surface of any metal flyer can be found. For most experiments employing VISAR, either a kinetic pressure [Grady, Mech. Mater. 29, 181 (1998)] or a magnetic pressure [Lemke et al., Intl J. Impact Eng. 38, 480 (2011)] drives the motion of the flyer. Moreover, reliable prediction of the time-dependent pressure is often a critical component to understanding the physics of these experiments. Although VISAR can provide a precise measurement of a flyer’s surface velocity, the real challenge of this diagnostic implementation is using this velocity to unfold the time-dependent pressure. The purpose of this study is to elucidate a new method for quickly and reliably unfolding VISAR data.

  6. Q-branch Raman scattering and modern kinetic thoery

    SciTech Connect (OSTI)

    Monchick, L.

    1993-12-01

    The program is an extension of previous APL work whose general aim was to calculate line shapes of nearly resonant isolated line transitions with solutions of a popular quantum kinetic equation-the Waldmann-Snider equation-using well known advanced solution techniques developed for the classical Boltzmann equation. The advanced techniques explored have been a BGK type approximation, which is termed the Generalized Hess Method (GHM), and conversion of the collision operator to a block diagonal matrix of symmetric collision kernels which then can be approximated by discrete ordinate methods. The latter method, which is termed the Collision Kernel method (CC), is capable of the highest accuracy and has been used quite successfully for Q-branch Raman scattering. The GHM method, not quite as accurate, is applicable over a wider range of pressures and has proven quite useful.

  7. Chemical Dynamics, Molecular Energetics, and Kinetics at the Synchrotron

    SciTech Connect (OSTI)

    Leone, Stephen R.; Ahmed, Musahid; Wilson, Kevin R.

    2010-03-14

    Scientists at the Chemical Dynamics Beamline of the Advanced Light Source in Berkeley are continuously reinventing synchrotron investigations of physical chemistry and chemical physics with vacuum ultraviolet light. One of the unique aspects of a synchrotron for chemical physics research is the widely tunable vacuum ultraviolet light that permits threshold ionization of large molecules with minimal fragmentation. This provides novel opportunities to assess molecular energetics and reaction mechanisms, even beyond simple gas phase molecules. In this perspective, significant new directions utilizing the capabilities at the Chemical Dynamics Beamline are presented, along with an outlook for future synchrotron and free electron laser science in chemical dynamics. Among the established and emerging fields of investigations are cluster and biological molecule spectroscopy and structure, combustion flame chemistry mechanisms, radical kinetics and product isomer dynamics, aerosol heterogeneous chemistry, planetary and interstellar chemistry, and secondary neutral ion-beam desorption imaging of biological matter and materials chemistry.

  8. High Temperature Chemical Kinetic Combustion Modeling of Lightly Methylated Alkanes

    SciTech Connect (OSTI)

    Sarathy, S M; Westbrook, C K; Pitz, W J; Mehl, M

    2011-03-01

    Conventional petroleum jet and diesel fuels, as well as alternative Fischer-Tropsch (FT) fuels and hydrotreated renewable jet (HRJ) fuels, contain high molecular weight lightly branched alkanes (i.e., methylalkanes) and straight chain alkanes (n-alkanes). Improving the combustion of these fuels in practical applications requires a fundamental understanding of large hydrocarbon combustion chemistry. This research project presents a detailed high temperature chemical kinetic mechanism for n-octane and three lightly branched isomers octane (i.e., 2-methylheptane, 3-methylheptane, and 2,5-dimethylhexane). The model is validated against experimental data from a variety of fundamental combustion devices. This new model is used to show how the location and number of methyl branches affects fuel reactivity including laminar flame speed and species formation.

  9. Kinetics of fluidized bed combustion of wood pellets

    SciTech Connect (OSTI)

    Leckner, B.; Hansson, K.M.; Tullin, C.; Borodulya, A.V.; Dikalenko, V.I.; Palchonok, G.I.

    1999-07-01

    Devolatilization and char combustion of a single wood pellet in a fluidized bed has been studied. The effect of operation parameters (bed temperature, bed particle size, oxygen concentration) and pellet characteristics has been investigated. A simplified analytical model of heat-transfer controlled pyrolysis has been developed to interpret the measured volatiles release time. The model predictions are in a good agreement with the experimental data, provided that the initial physical properties of the pellet are used. The model can be used to estimate the devolatilization times in other combustion systems. Kinetic parameters of char combustion are obtained, based on the measured burnout times and simple model considerations. The physical properties of wood pellets need further study.

  10. Chemical kinetic modeling of component mixtures relevant to gasoline

    SciTech Connect (OSTI)

    Mehl, M; Curran, H J; Pitz, W J; Westbrook, C K

    2009-02-13

    Real fuels are complex mixtures of thousands of hydrocarbon compounds including linear and branched paraffins, naphthenes, olefins and aromatics. It is generally agreed that their behavior can be effectively reproduced by simpler fuel surrogates containing a limited number of components. In this work, a recently revised version of the kinetic model by the authors is used to analyze the combustion behavior of several components relevant to gasoline surrogate formulation. Particular attention is devoted to linear and branched saturated hydrocarbons (PRF mixtures), olefins (1-hexene) and aromatics (toluene). Model predictions for pure components, binary mixtures and multi-component gasoline surrogates are compared with recent experimental information collected in rapid compression machine, shock tube and jet stirred reactors covering a wide range of conditions pertinent to internal combustion engines. Simulation results are discussed focusing attention on the mixing effects of the fuel components.

  11. Utilization of rotor kinetic energy storage for hybrid vehicles

    SciTech Connect (OSTI)

    Hsu, John S.

    2011-05-03

    A power system for a motor vehicle having an internal combustion engine, the power system comprises an electric machine (12) further comprising a first excitation source (47), a permanent magnet rotor (28) and a magnetic coupling rotor (26) spaced from the permanent magnet rotor and at least one second excitation source (43), the magnetic coupling rotor (26) also including a flywheel having an inertial mass to store kinetic energy during an initial acceleration to an operating speed; and wherein the first excitation source is electrically connected to the second excitation source for power cycling such that the flywheel rotor (26) exerts torque on the permanent magnet rotor (28) to assist braking and acceleration of the permanent magnet rotor (28) and consequently, the vehicle. An axial gap machine and a radial gap machine are disclosed and methods of the invention are also disclosed.

  12. Temperature estimates from zircaloy oxidation kinetics and microstructures. [PWR

    SciTech Connect (OSTI)

    Olsen, C.S.

    1982-10-01

    This report reviews state-of-the-art capability to determine peak zircaloy fuel rod cladding temperatures following an abnormal temperature excursion in a nuclear reactor, based on postirradiation metallographic analysis of zircaloy microstructural and oxidation characteristics. Results of a comprehensive literature search are presented to evaluate the suitability of available zircaloy microstructural and oxidation data for estimating anticipated reactor fuel rod cladding temperatures. Additional oxidation experiments were conducted to evaluate low-temperature zircaloy oxidation characteristics for postirradiation estimation of cladding temperature by metallographic examination. Results of these experiments were used to calculate peak cladding temperatures of electrical heater rods and nuclear fuel rods that had been subjected to reactor temperature transients. Comparison of the calculated and measured peak cladding temperatures for these rods indicates that oxidation kinetics is a viable technique for estimating peak cladding temperatures over a broad temperature range. However, further improvement in zircaloy microstructure technology is necessary for precise estimation of peak cladding temperatures by microstructural examination.

  13. An Experimental and Kinetic Modeling Study of Methyl Decanoate Combustion

    SciTech Connect (OSTI)

    Sarathy, S M; Thomson, M J; Pitz, W J; Lu, T

    2010-02-19

    Biodiesel is typically a mixture of long chain fatty acid methyl esters for use in compression ignition engines. Improving biofuel engine performance requires understanding its fundamental combustion properties and the pathways of combustion. This research study presents new combustion data for methyl decanoate in an opposed-flow diffusion flame. An improved detailed chemical kinetic model for methyl decanoate combustion is developed, which serves as the basis for deriving a skeletal mechanism via the direct relation graph method. The novel skeletal mechanism consists of 648 species and 2998 reactions. This mechanism well predicts the methyl decanoate opposed-flow diffusion flame data. The results from the flame simulations indicate that methyl decanoate is consumed via abstraction of hydrogen atoms to produce fuel radicals, which lead to the production of alkenes. The ester moiety in methyl decanoate leads to the formation of low molecular weight oxygenated compounds such as carbon monoxide, formaldehyde, and ketene.

  14. On the kinetic barriers of graphene homo-epitaxy

    SciTech Connect (OSTI)

    Zhang, Wei; Yu, Xinke; Xie, Ya-Hong; Cahyadi, Erica; Ratsch, Christian

    2014-12-01

    The diffusion processes and kinetic barriers of individual carbon adatoms and clusters on graphene surfaces are investigated to provide fundamental understanding of the physics governing epitaxial growth of multilayer graphene. It is found that individual carbon adatoms form bonds with the underlying graphene whereas the interaction between graphene and carbon clusters, consisting of 6 atoms or more, is very weak being van der Waals in nature. Therefore, small carbon clusters are quite mobile on the graphene surfaces and the diffusion barrier is negligibly small (?6?meV). This suggests the feasibility of high-quality graphene epitaxial growth at very low growth temperatures with small carbon clusters (e.g., hexagons) as carbon source. We propose that the growth mode is totally different from 3-dimensional bulk materials with the surface mobility of carbon hexagons being the highest over graphene surfaces that gradually decreases with further increase in cluster size.

  15. Infrared Absorption Spectroscopy and Chemical Kinetics of Free Radicals

    SciTech Connect (OSTI)

    Curl, Robert F; Glass, Graham

    2004-11-01

    This research was directed at the detection, monitoring, and study of the chemical kinetic behavior by infrared absorption spectroscopy of small free radical species thought to be important intermediates in combustion. Work on the reaction of OH with acetaldehyde has been completed and published and work on the reaction of O({sup 1}D) with CH{sub 4} has been completed and submitted for publication. In the course of our investigation of branching ratios of the reactions of O({sup 1}D) with acetaldehyde and methane, we discovered that hot atom chemistry effects are not negligible at the gas pressures (13 Torr) initially used. Branching ratios of the reaction of O({sup 1}D) with CH{sub 4} have been measured at a tenfold higher He flow and fivefold higher pressure.

  16. Alkaline assisted thermal oil recovery: Kinetic and displacement studies

    SciTech Connect (OSTI)

    Saneie, S.; Yortsos, Y.C.

    1993-06-01

    This report deals with two major issues of chemical assisted flooding - the interaction of caustic, one of the proposed additives to steam flood, with the reservoir rock, and the displacement of oil by a chemical flood at elevated temperatures. A mathematical model simulating the kinetics of silica dissolution and hydroxyl ion consumption in a typical alkaline flooding environment is first developed. The model is based on the premise that dissolution occurs via hydrolysis of active sites through the formation of an intermediate complex, which is in equilibrium with the silicic acid in solution. Both static (batch) and dynamic (core flood) processes are simulated to examine the sensitivity of caustic consumption and silica dissolution to process parameters, and to determine rates of propagation of pH values. The model presented provides a quantitative description of the quartz-alkali interaction in terms of pH, salinity, ion exchange properties, temperature and contact time, which are of significant importance in the design of soluble silicate flooding processes. The modeling of an adiabatic hot waterflood assisted by the simultaneous injection of a chemical additive is next presented. The model is also applicable to the hot alkaline flooding under conditions of negligible adsorption of the generated anionic surfactant and of hydroxide adsorption being Langmuirian. The theory of generalized simple waves (coherence ) is used to develop solutions for the temperature, concentration, and oil saturation profiles, as well as the oil recovery curves. It is shown that, for Langmuir adsorption kinetics, the chemical resides in the heated region of the reservoir if its injection concentration is below a critical value, and in the unheated region if its concentration exceeds this critical value. Results for a chemical slug injection in a tertiary recovery process indicate recovery performance is maximized when chemical resides in the heated region of the reservior.

  17. Parameter estimation for models of ligninolytic and cellulolytic enzyme kinetics

    SciTech Connect (OSTI)

    Wang, Gangsheng; Post, Wilfred M; Mayes, Melanie; Frerichs, Joshua T; Jagadamma, Sindhu

    2012-01-01

    While soil enzymes have been explicitly included in the soil organic carbon (SOC) decomposition models, there is a serious lack of suitable data for model parameterization. This study provides well-documented enzymatic parameters for application in enzyme-driven SOC decomposition models from a compilation and analysis of published measurements. In particular, we developed appropriate kinetic parameters for five typical ligninolytic and cellulolytic enzymes ( -glucosidase, cellobiohydrolase, endo-glucanase, peroxidase, and phenol oxidase). The kinetic parameters included the maximum specific enzyme activity (Vmax) and half-saturation constant (Km) in the Michaelis-Menten equation. The activation energy (Ea) and the pH optimum and sensitivity (pHopt and pHsen) were also analyzed. pHsen was estimated by fitting an exponential-quadratic function. The Vmax values, often presented in different units under various measurement conditions, were converted into the same units at a reference temperature (20 C) and pHopt. Major conclusions are: (i) Both Vmax and Km were log-normal distributed, with no significant difference in Vmax exhibited between enzymes originating from bacteria or fungi. (ii) No significant difference in Vmax was found between cellulases and ligninases; however, there was significant difference in Km between them. (iii) Ligninases had higher Ea values and lower pHopt than cellulases; average ratio of pHsen to pHopt ranged 0.3 0.4 for the five enzymes, which means that an increase or decrease of 1.1 1.7 pH units from pHopt would reduce Vmax by 50%. (iv) Our analysis indicated that the Vmax values from lab measurements with purified enzymes were 1 2 orders of magnitude higher than those for use in SOC decomposition models under field conditions.

  18. Energy dynamics and current sheet structure in fluid and kinetic simulations of decaying magnetohydrodynamic turbulence

    SciTech Connect (OSTI)

    Makwana, K. D. Cattaneo, F.; Zhdankin, V.; Li, H.; Daughton, W.

    2015-04-15

    Simulations of decaying magnetohydrodynamic (MHD) turbulence are performed with a fluid and a kinetic code. The initial condition is an ensemble of long-wavelength, counter-propagating, shear-Alfvén waves, which interact and rapidly generate strong MHD turbulence. The total energy is conserved and the rate of turbulent energy decay is very similar in both codes, although the fluid code has numerical dissipation, whereas the kinetic code has kinetic dissipation. The inertial range power spectrum index is similar in both the codes. The fluid code shows a perpendicular wavenumber spectral slope of k{sub ⊥}{sup −1.3}. The kinetic code shows a spectral slope of k{sub ⊥}{sup −1.5} for smaller simulation domain, and k{sub ⊥}{sup −1.3} for larger domain. We estimate that collisionless damping mechanisms in the kinetic code can account for the dissipation of the observed nonlinear energy cascade. Current sheets are geometrically characterized. Their lengths and widths are in good agreement between the two codes. The length scales linearly with the driving scale of the turbulence. In the fluid code, their thickness is determined by the grid resolution as there is no explicit diffusivity. In the kinetic code, their thickness is very close to the skin-depth, irrespective of the grid resolution. This work shows that kinetic codes can reproduce the MHD inertial range dynamics at large scales, while at the same time capturing important kinetic physics at small scales.

  19. CHEMKIN-III: A FORTRAN chemical kinetics package for the analysis of gas-phase chemical and plasma kinetics

    SciTech Connect (OSTI)

    Kee, R.J.; Rupley, F.M.; Meeks, E.; Miller, J.A.

    1996-05-01

    This document is the user`s manual for the third-generation CHEMKIN package. CHEMKIN is a software package whose purpose is to facilitate the formation, solution, and interpretation of problems involving elementary gas-phase chemical kinetics. It provides a flexible and powerful tool for incorporating complex chemical kinetics into simulations of fluid dynamics. The package consists of two major software components: an Interpreter and a Gas-Phase Subroutine Library. The Interpreter is a program that reads a symbolic description of an elementary, user-specified chemical reaction mechanism. One output from the Interpreter is a data file that forms a link to the Gas-Phase Subroutine Library. This library is a collection of about 100 highly modular FORTRAN subroutines that may be called to return information on equations of state, thermodynamic properties, and chemical production rates. CHEMKIN-III includes capabilities for treating multi-fluid plasma systems, that are not in thermal equilibrium. These new capabilities allow researchers to describe chemistry systems that are characterized by more than one temperature, in which reactions may depend on temperatures associated with different species; i.e. reactions may be driven by collisions with electrons, ions, or charge-neutral species. These new features have been implemented in such a way as to require little or no changes to CHEMKIN implementation for systems in thermal equilibrium, where all species share the same gas temperature. CHEMKIN-III now has the capability to handle weakly ionized plasma chemistry, especially for application related to advanced semiconductor processing.

  20. Pattern Formation and Growth Kinetics in Eutectic Systems

    SciTech Connect (OSTI)

    Jing Teng

    2007-12-01

    Growth patterns during liquid/solid phase transformation are governed by simultaneous effects of heat and mass transfer mechanisms, creation of new interfaces, jump of the crystallization units from liquid to solid and their rearrangement in the solid matrix. To examine how the above processes influence the scale of microstructure, two eutectic systems are chosen for the study: a polymeric system polyethylene glycol-p-dibromobenzene (PEG-DBBZ) and a simple molecular system succinonitrile (SCN)-camphor. The scaling law for SCN-camphor system is found to follow the classical Jackson-Hunt model of circular rod eutectic, where the diffusion in the liquid and the interface energy are the main physics governing the two-phase pattern. In contrast, a significantly different scaling law is observed for the polymer system. The interface kinetics of PEG phase and its solute concentration dependence thus have been critically investigated for the first time by directional solidification technique. A model is then proposed that shows that the two-phase pattern in polymers is governed by the interface diffusion and the interface kinetics. In SCN-camphor system, a new branch of eutectic, elliptical shape rodl, is found in thin samples where only one layer of camphor rods is present. It is found that the orientation of the ellipse can change from the major axis in the direction of the thickness to the direction of the width as the velocity and/or the sample thickness is decreased. A theoretical model is developed that predicts the spacing and orientation of the elliptical rods in a thin sample. The single phase growth patterns of SCN-camphor system were also examined with emphasis on the three-dimensional single cell and cell/dendrite transition. For the 3D single cell in a capillary tube, the entire cell shape ahead of the eutectic front can be described by the Saffmann-Taylor finger only at extremely low growth rate. A 3D directional solidification model is developed to

  1. A D O E En

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    power to enhance clean energy production A D O E En e rg y Inn ov ati o n H ub Nuclear Energy Cover photo: 3D visualizations allow a physical walk-through of the top 20% of...

  2. Utilization of Kinetic Isotope Effects for the Concentration of Tritium

    SciTech Connect (OSTI)

    Brown, Gilbert M.; Meyer, Thomas J.; Moyer, Bruce A.

    2000-06-01

    Work is in progress to develop methods for concentrating tritium in water based on large primary isotope effects in catalytic redox processes. Basic research is being conducted to develop the chemistry of a complete cyclic process. The process will remove tritium from H2O by concentrating it with respect to protio-water. This research involves developing chemical cycles that produce high concentration factors for HTO based on the discrimination of CH and C-T bonds in oxidation reactions. Several steps are required in a cyclic process for the concentration of tritium in water. In the first step, the tritium is incorporated in an organic compound. H-T discrimination occurs as the tritium containing compound is oxidized in a step involving a Ru(IV) oxo complex. Strong primary kinetic isotope effects lead to the oxidation of C-H bonds in preference to C-T bonds, and this reaction leads to concentration of tritium in the organic compound. The reduced form of the ruthenium compound can be reoxidized so that the oxidation step can be made catalytic.

  3. Kinetic Effects in Multiple Intra-Beam Scattering

    SciTech Connect (OSTI)

    Zenkevich, P.; Bolshakov, A.; Boine-Frankenheim, O.

    2005-06-08

    The analysis of the evolution in phase space induced by multiple intra-beam scattering (IBS) requires the solution of the Fokker-Planck equation (FPE) or of similar kinetic equations. The FPE is formulated in coordinate-momentum space (6 variables). Using the 'semi-Gaussian model' this equation is reduced to the longitudinal FPE that depends on longitudinal momentum and coordinate; drift and diffusion coefficients in this equation are presented as integrals on distribution function with kernels expressed in analytical form. The number of variables in the FPE can be reduced to three by reformulation in the space of invariants. The invariant-vector has the following components: a longitudinal energy (for the longitudinal degree of freedom) and the Courant-Snyder invariants (for the transverse motion). The coefficients of the FPE in invariant space are in the form of integrals over the distribution function and the invariants with the kernel in the form of many-dimensional integrals over the longitudinal variable and over the oscillation phases. The three-dimensional FPE can be solved numerically by application of macro-particle codes using the different methods: 1) Langevin method; 2) binary collision map. The last method is used in the code 'MOCAC' (MOnte CArlo Code) for IBS simulation. Examples of code validation and application are discussed.

  4. Simulation of carbon gasification kinetics using an edge recession model

    SciTech Connect (OSTI)

    Takashi Kyotani; Leon y Leon, C.A.L.; Radovic, L.R. )

    1993-07-01

    An edge recession modeling method is proposed as a new approach to the prediction of carbon gasification kinetics. Using this method, the variations in reactive surface area (RSA) and specific reactivity (R) with conversion were simulated for several polynuclear aromatic molecules adopted as models of carbon crystallites. The effects of crystallite size and shape, edge site reactivity and vacancies on the changes in RSA and R with conversion were investigated. As a result, RSA and R were found to be essentially independent of crystallite shape, but to depend on crystallite size and the presence of vacancies. Good agreement was obtained between model predictions and experimental data for several kinds of model carbon crystallites. In the case of structurally disordered carbons (such as chars), simultaneous gasification of model crystallites of two different sizes gave better predictions than that of single-size crystallites. The edge recession model is proposed as an alternative, or at least complementary, approach to the more conventional (and, arguably, less physically meaningful) pore structure development models.

  5. Cosmic rays from leptophilic dark matter decay via kinetic mixing

    SciTech Connect (OSTI)

    Ibarra, Alejandro; Tran, David; Ringwald, Andreas; Weniger, Christoph E-mail: andreas.ringwald@desy.de E-mail: christoph.weniger@desy.de

    2009-08-01

    If interpreted in terms of decaying dark matter, the steep rise in the positron fraction of cosmic rays above 10 GeV, as observed by the PAMELA experiment, suggests an underlying production mechanism that favors leptonic channels. We consider a scenario where a portion of the dark matter is made of the gauginos of an unbroken hidden-sector U(1){sub X}, which interact with the visible sector only through a tiny kinetic mixing. The second component of the dark matter is made of neutralinos, and depending on the mass spectrum, either the lightest neutralino or the hidden gaugino becomes unstable and subject to decay. We analyze the cosmic rays, namely the contributions to the positron, the extragalactic gamma-ray and the antiproton flux, which potentially result from these decays and demonstrate that the production of antiprotons can be naturally suppressed. Furthermore, we briefly discuss the apparent double-peak structure of the ATIC data in light of cascade-decaying hidden gauginos, as well as possible signatures at Fermi.

  6. Effect of Dust Grains on Solitary Kinetic Alfven Wave

    SciTech Connect (OSTI)

    Li Yangfang; Wu, D. J.; Morfill, G. E.

    2008-09-07

    Solitary kinetic Alfven wave has been studied in dusty plasmas. The effect of the dust charge-to-mass ratio is considered. We derive the Sagdeev potential for the soliton solutions based on the hydrodynamic equations. A singularity in the Sagdeev potential is found and this singularity results in a bell-shaped soliton. The soliton solutions comprise two branches. One branch is sub-Alfvenic and the soliton velocities are much smaller than the Alfven speed. The other branch is super-Alfvenic and the soliton velocities are very close to or greater than the Alfven speed. Both compressive and rarefactive solitons can exist in each branch. For the sub-Alfvenic branch, the rarefactive soliton is a bell shape curve which is much narrower than the compressive one. In the super-Alfvenic branch, however, the compressive soliton is bell-shaped and the rarefactive one is broadened. We also found that the super-Alfvenic solitons can develop to other structures. When the charge-to-mass ratio of the dust grains is sufficiently high, the width of the rarefactive soliton will increase extremely and an electron density depletion will be observed. When the velocity is much higher than the Alfven speed, the bell-shaped soliton will transit to a cusped structure.

  7. Oxidation kinetics of calcium-doped palladium powders

    SciTech Connect (OSTI)

    Jain, S.; Kodas, T.T.; Hampden-Smith, M. [Univ. of New Mexico, Albuquerque, NM (United States)

    1997-04-01

    The oxidation kinetics of submicron Ca-containing Pd powders produced by spray pyrolysis were studied in the temperature range 600 to 675 C using thermogravimetric analysis. The oxidation of pure Pd powder had an activation energy of {approximately}230 kJ/mol in the region 27% < oxidation < 70% and 65 kJ/mol for oxidation > 70%. The activation energies for Pd particles containing 0.01 weight percent (w/o) and 0.4 w/o Ca in the region 27% < oxidation < 70% were {approximately}230 kJ/mol and {approximately}50 kJ/mol, respectively. Transmission electron microscopy suggested that the conversion of Pd to Pd{sup II}O (stoichiometric PdO) proceeds from the particle surface into the interior and not homogeneously throughout the particle. The predictions of a variety of models and rate laws (shrinking core, parabolic, cubic, logarithmic, and inverse logarithmic) were compared with the data. The comparison suggested a mechanism in which oxidation of pure Pd proceeds by chemisorption and diffusion of oxygen to form a substoichiometric oxide, followed by the conversion of substoichiometric PdO to Pd{sup II}O. Oxidation of pure Pd is then probably limited by the diffusion of oxygen through the substoichiometric PdO and/or Pd{sup II}O. The addition of Ca increased the oxidation resistance of Pd most likely by inhibiting oxygen diffusion through the metal oxide layers surrounding the Pd.

  8. Interface-Driven Phenomena in Solids: Thermodynamics, Kinetics and Chemistry

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Abdeljawad, Fadi; Foiles, Stephen M.

    2016-05-04

    The study of materials interfaces dates back over a century. In solid systems and from an engineering perspective, free surfaces and internal (grain and/or phase) boundaries influence a wide range of properties, such as thermal, electrical and optical transport, and mechanical ones. The properties and the role of interfaces has been discussed extensively in various reviews such as by Sutton and Balluffi. As the characteristic feature size of a materials system (i.e., grain size) is decreased to the nanometer scale, interface-driven physics is expected to dominate due to the increased density of such planar defects. Moreover, interfacial attributes, thermodynamics, andmore » mobility play a key role in phase transformations, such as solidification dynamics and structural transitions in solids, and in homogenization and microstructural evolution processes, such as grain growth, coarsening, and recrystallization. In summary, the set of articles published in this special topic titled: “Interface-Driven Phenomena in Solids: Thermodynamics, Kinetics and Chemistry” covers topics related to microstructure evolution, segregation/adsorption phenomena and interface interactions with other materials defects.« less

  9. KINETICS OF SLURRY PHASE FISCHER-TROPSCH SYNTHESIS

    SciTech Connect (OSTI)

    Dragomir B. Bukur

    2004-09-29

    This report covers the second year of this three-year research grant under the University Coal Research program. The overall objective of this project is to develop a comprehensive kinetic model for slurry phase Fischer-Tropsch synthesis on iron catalysts. This model will be validated with experimental data obtained in a stirred tank slurry reactor (STSR) over a wide range of process conditions. The model will be able to predict concentrations of all reactants and major product species (H{sub 2}O, CO{sub 2}, linear 1- and 2-olefins, and linear paraffins) as a function of reaction conditions in the STSR. During the second year of the project we completed the STSR test SB-26203 (275-343 h on stream), which was initiated during the first year of the project, and another STSR test (SB-28603 lasting 341 h). Since the inception of the project we completed 3 STSR tests, and evaluated catalyst under 25 different sets of process conditions. A precipitated iron catalyst obtained from Ruhrchemie AG (Oberhausen-Holten, Germany) was used in all tests. This catalyst was used initially in commercial fixed bed reactors at Sasol in South Africa. Also, during the second year we performed a qualitative analysis of experimental data from all three STSR tests. Effects of process conditions (reaction temperature, pressure, feed composition and gas space velocity) on water-gas-shift (WGS) activity and hydrocarbon product distribution have been determined.

  10. KINETICS OF SLURRY PHASE FISCHER-TROPSCH SYNTHESIS

    SciTech Connect (OSTI)

    Dragomir B. Bukur; Gilbert F. Froment; Lech Nowicki; Jiang Wang; Wen-Ping Ma

    2003-09-29

    This report covers the first year of this three-year research grant under the University Coal Research program. The overall objective of this project is to develop a comprehensive kinetic model for slurry phase Fischer-Tropsch synthesis on iron catalysts. This model will be validated with experimental data obtained in a stirred tank slurry reactor (STSR) over a wide range of process conditions. The model will be able to predict concentrations of all reactants and major product species (H{sup 2}O, CO{sub 2}, linear 1- and 2-olefins, and linear paraffins) as a function of reaction conditions in the STSR. During the reporting period we have completed one STSR test with precipitated iron catalyst obtained from Ruhrchemie AG (Oberhausen-Holten, Germany). This catalyst was initially in commercial fixed bed reactors at Sasol in South Africa. The catalyst was tested at 13 different sets of process conditions, and had experienced a moderate deactivation during the first 500 h of testing (decrease in conversion from 56% to 50% at baseline process conditions). The second STSR test has been initiated and after 270 h on stream, the catalyst was tested at 6 different sets of process conditions.