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


1

Direct Kinetic Measurements of a Criegee Intermediate  

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

Direct Kinetic Measurements of a Criegee Intermediate Print 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 of hydrocarbon), via reaction with ozone, a key pollutant in the troposphere. Although there has been much indirect evidence supporting Criegee's mechanism, breakthrough research done at the ALS by chemists from Sandia National Laboratories, the University of Manchester, and Bristol University has for the first time directly measured reaction rates for so-called "Criegee intermediates," elusive molecules formed at intermediate stages of ozonolysis. The surprising results may have important implications for subjects ranging from advanced engine design to air quality and climate modeling.

2

MEASUREMENTS, ERRORS, AND NEGATIVE KINETIC ENERGY  

E-Print Network (OSTI)

An analysis of errors in measurement yields new insight into the penetration of quantum particles into classically forbidden regions. In addition to “physical” values, realistic measurements yield “unphysical ” values which, we show, can form a consistent pattern. An experiment to isolate a particle in a classically forbidden region obtains negative values for its kinetic energy. These values realize the concept of a weak value, discussed in previous works. 0

Yakir Aharonov; Sandu Popescu; Daniel Rohrlich; Lev Vaidman

1993-01-01T23:59:59.000Z

3

A Direct Measure of Entrainment  

Science Conference Proceedings (OSTI)

A method is introduced for directly measuring convective entrainment and detrainment in a cloud-resolving simulation. This technique is used to quantify the errors in the entrainment and detrainment estimates obtained using the standard bulk-...

David M. Romps

2010-06-01T23:59:59.000Z

4

Direct measure of quantum correlation  

SciTech Connect

The quantumness of the correlation known as quantum correlation is usually measured by quantum discord. So far various quantum discords can be roughly understood as indirect measure by some special discrepancy of two quantities. We present a direct measure of quantum correlation by revealing the difference between the structures of classically and quantum correlated states. Our measure explicitly includes the contributions of the inseparability and local nonorthogonality of the eigenvectors of a density matrix. Besides its relatively easy computability, our measure can provide a unified understanding of quantum correlation of all the present versions.

Yu, Chang-shui [School of Physics and Optoelectronic Technology, Dalian University of Technology, Dalian 116024 (China); H. H. Wills Physics Laboratory, University of Bristol, Tyndall Avenue, Bristol BS8 1TL (United Kingdom); Zhao, Haiqing [School of Science, Dalian Jiaotong University, Dalian 116028 (China)

2011-12-15T23:59:59.000Z

5

Direct Kinetic Measurements of a Criegee Intermediate  

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

well as enable new detection methods beyond photoionization that might be deployed for in situ atmospheric sensing. Sandia combustion researchers Craig Taatjes and David Osborn...

6

Turbulence Kinetic Energy Budget Profiles Derived from Doppler Sodar Measurements  

Science Conference Proceedings (OSTI)

Doppler sodar wind measurements made in light wind conditions in September 1979 near a power plant in Turbigo, Italy, are used to derive terms in the turbulence kinetic energy (TKE) budget. Measurements on five days are grouped into two classes: ...

Gary K. Greenhut; Giangiuseppe Mastrantonio

1989-02-01T23:59:59.000Z

7

Measuring Dark Matter Distribution in Directional Direct Detection  

E-Print Network (OSTI)

Direct detection of dark matter with directional sensitivity offers not only measurement of both recoil energy and direction of dark matter, but also a way to understand dark matter distribution in the Galaxy. Maxwell distribution is usually supposed as the distribution near the Earth, however, deviation from that, caused by tidal streams in the Galaxy, has been suggested. We explore the possibility of distinguishing the distribution by direct detection using nuclear emulsions.

Keiko I. Nagao

2013-12-11T23:59:59.000Z

8

Direct Measurements of the Luzon Undercurrent  

Science Conference Proceedings (OSTI)

The Luzon Undercurrent (LUC) was discovered about 20 years ago by geostrophic calculation from conductivity–temperature–depth (CTD) data. But it was not directly measured until 2010. From November 2010 to July 2011, the LUC was first directly ...

Dunxin Hu; Shijian Hu; Lixin Wu; Lei Li; Linlin Zhang; Xinyuan Diao; Zhaohui Chen; Yuanlong Li; Fan Wang; Dongliang Yuan

2013-07-01T23:59:59.000Z

9

Worldwide Measurements of Directional Wave Spreading  

Science Conference Proceedings (OSTI)

The directional spreading of waves is important for both theoretical and practical reasons. Enough measurements have now been made to draw conclusions about the behavior of wave spreading at sites in different climatic regimes. The measurements ...

George Z. Forristall; Kevin C. Ewans

1998-04-01T23:59:59.000Z

10

A direct search method for determination of DAEM kinetic parameters from nonisothermal TGA data (note)  

Science Conference Proceedings (OSTI)

In this study, a simple direct search method to be used for the determination of distributed activation energy model (DAEM) kinetic parameters from the nonisothermal thermogravimetric analysis (TGA) data of coals has been introduced. Process steps of ... Keywords: curve fitting, direct search technique, distributed activation energy model (DAEM), thermogravimetric analysis data (TGA)

Mustafa Güne?; Semin Güne?

2002-08-01T23:59:59.000Z

11

ARM - Measurement - Shortwave broadband direct normal irradiance  

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

normal irradiance normal irradiance ARM Data Discovery Browse Data Comments? We would love to hear from you! Send us a note below or call us at 1-888-ARM-DATA. Send Measurement : Shortwave broadband direct normal irradiance The rate at which radiant energy in broad bands of wavelengths shorter than approximately 4{mu}m, that comes directly from the Sun without being scattered or absorbed in the atmosphere, passes through a unit area perpendicular to the direction from the Sun. Categories Radiometric Instruments The above measurement is considered scientifically relevant for the following instruments. Refer to the datastream (netcdf) file headers of each instrument for a list of all available measurements, including those recorded for diagnostic or quality assurance purposes. ARM Instruments

12

ARM - Measurement - Shortwave narrowband direct downwelling irradiance  

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

downwelling irradiance downwelling irradiance ARM Data Discovery Browse Data Comments? We would love to hear from you! Send us a note below or call us at 1-888-ARM-DATA. Send Measurement : Shortwave narrowband direct downwelling irradiance The direct unscattered radiant energy from the Sun, in a narrow band of wavelengths shorter than approximately 4 {mu}m, passing through a horizontal unit area in a downward direction. Categories Radiometric Instruments The above measurement is considered scientifically relevant for the following instruments. Refer to the datastream (netcdf) file headers of each instrument for a list of all available measurements, including those recorded for diagnostic or quality assurance purposes. Field Campaign Instruments SOAR : Shipboard Oceanographic and Atmospheric Radiation

13

KINETICS OF DIRECT OXIDATION OF H2S IN COAL GAS TO ELEMENTAL SULFUR  

DOE Green Energy (OSTI)

The direct oxidation of H{sub 2}S to elemental sulfur in the presence of SO{sub 2} is ideally suited for coal gas from commercial gasifiers with a quench system to remove essentially all the trace contaminants except H{sub 2}S. This direct oxidation process has the potential to produce a super clean coal gas more economically than both conventional amine-based processes and the hot-gas desulfurization using regenerable metal oxide sorbents followed by Direct Sulfur Recovery Process. The objective of this research is to support the near- and long-term process development efforts to commercialize this direct oxidation technology. The objectives of this research are to measure kinetics of direct oxidation of H{sub 2}S to elemental sulfur in the presence of a simulated coal gas mixture containing SO{sub 2}, H{sub 2}, and moisture, using 160-{micro}m C-500-04 alumina catalyst particles and a micro bubble reactor, and to develop kinetic rate equations and model the direct oxidation process to assist in the design of large-scale plants. This heterogeneous catalytic reaction has gaseous reactants such as H{sub 2}S and SO{sub 2}. However, this heterogeneous catalytic reaction has heterogeneous products such as liquid elemental sulfur and steam. To achieve the above-mentioned objectives, experiments on conversion of hydrogen sulfide into liquid elemental sulfur were carried out for the space time range of 1-6 milliseconds at 125-155 C to evaluate effects of reaction temperature, moisture concentration, reaction pressure on conversion of hydrogen sulfide into liquid elemental sulfur. Simulated coal gas mixtures consist of 70 v% hydrogen, 2,500-7,500-ppmv hydrogen sulfide, 1,250-3,750 ppmv sulfur dioxide, and 0-15 vol% moisture, and nitrogen as remainder. Volumetric feed rates of a simulated coal gas mixture to a micro bubble reactor are 100 cm{sup 3}/min at room temperature and atmospheric pressure. The temperature of the reactor is controlled in an oven at 125-155 C. The pressure of the reactor is maintained at 40-170 psia.

K.C. Kwon

2004-01-01T23:59:59.000Z

14

KINETICS OF DIRECT OXIDATION OF H2S IN COAL GAS TO ELEMENTAL SULFUR  

DOE Green Energy (OSTI)

The direct oxidation of H{sub 2}S to elemental sulfur in the presence of SO{sub 2} is ideally suited for coal gas from commercial gasifiers with a quench system to remove essentially all the trace contaminants except H{sub 2}S. This direct oxidation process has the potential to produce a super clean coal gas more economically than both conventional amine-based processes and the hot-gas desulfurization using regenerable metal oxide sorbents followed by Direct Sulfur Recovery Process. The objective of this research is to support the near- and long-term process development efforts to commercialize this direct oxidation technology. The objectives of this research are to measure kinetics of direct oxidation of H{sub 2}S to elemental sulfur in the presence of a simulated coal gas mixture containing SO{sub 2}, H{sub 2}, and moisture, using 160-{micro}m C-500-04 alumina catalyst particles and a micro bubble reactor, and to develop kinetic rate equations and model the direct oxidation process to assist in the design of large-scale plants. This heterogeneous catalytic reaction has gaseous reactants such as H{sub 2}S and SO{sub 2}. However, this heterogeneous catalytic reaction has heterogeneous products such as liquid elemental sulfur and steam. To achieve the above-mentioned objectives, experiments on conversion of hydrogen sulfide into liquid elemental sulfur were carried out for the space time range of 0.059-0.87 seconds at 125-155 C to evaluate effects of reaction temperature, H{sub 2}S concentration, reaction pressure, and catalyst loading on conversion of hydrogen sulfide into liquid elemental sulfur. Simulated coal gas mixtures consist of 62-78 v% hydrogen, 3,000-7,000-ppmv hydrogen sulfide, 1,500-3,500 ppmv sulfur dioxide, and 10 vol % moisture, and nitrogen as remainder. Volumetric feed rates of a simulated coal gas mixture to a micro bubble reactor are 50 cm{sup 3}/min at room temperature and atmospheric pressure. The temperature of the reactor is controlled in an oven at 125-155 C. The pressure of the reactor is maintained at 40-170 psia. The molar ratio of H{sub 2}S to SO{sub 2} in the bubble reactor is maintained at 2 for all the reaction experiment runs.

K.C. Kwon

2005-01-01T23:59:59.000Z

15

Kinetics of Direct Oxidation of H2S in Coal Gas to Elemental Sulfur  

SciTech Connect

Removal of hydrogen sulfide (H{sub 2}S) from coal gasifier gas and sulfur recovery are key steps in the development of Department of Energy's (DOE's) advanced Vision 21 plants that produce electric power and clean transportation fuels with coal and natural gas. These Vision 21 plants will require highly clean coal gas with H{sub 2}S below 1 ppm and negligible amounts of trace contaminants such as hydrogen chloride, ammonia, alkali, heavy metals, and particulate. The conventional method of sulfur removal and recovery employing amine, Claus, and tail-gas treatment is very expensive. A second generation approach developed under DOE's sponsorship employs hot-gas desulfurization (HGD) using regenerable metal oxide sorbents followed by Direct Sulfur Recovery Process (DSRP). However, this process sequence does not remove trace contaminants and is targeted primarily towards the development of advanced integrated gasification combined cycle (IGCC) plants that produce electricity (not both electricity and transportation fuels). There is an immediate as well as long-term need for the development of cleanup processes that produce highly clean coal gas for next generation Vision 21 plants. To this end, a novel process is now under development at several research organizations in which the H{sub 2}S in coal gas is directly oxidized to elemental sulfur over a selective catalyst. Such a process is ideally suited for coal gas from commercial gasifiers with a quench system to remove essentially all the trace contaminants except H{sub 2}S. The direct oxidation of H{sub 2}S to elemental sulfur in the presence of SO{sub 2} is ideally suited for coal gas from commercial gasifiers with a quench system to remove essentially all the trace contaminants except H{sub 2}S. This direct oxidation process has the potential to produce a super clean coal gas more economically than both conventional amine-based processes and HGD/DSRP. The objectives of this research are to measure kinetics of direct oxidation of H{sub 2}S to elemental sulfur in the presence of a simulated coal gas mixture containing SO{sub 2}, H{sub 2}, and moisture, using 160-{micro}m C-500-04 alumina catalyst particles and 400 square cells/inch{sup 2}, {gamma}-Al{sub 2}O{sub 3}-wash-coated monolithic catalyst, and various reactors such as a micro packed-bed reactor, a micro bubble reactor, and a monolithic catalyst reactor, and to develop kinetic rate equations and model the direct oxidation process to assist in the design of large-scale plants. This heterogeneous catalytic reaction has gaseous reactants such as H{sub 2}S and SO{sub 2}. However, this heterogeneous catalytic reaction has heterogeneous products such as liquid elemental sulfur and steam.

K.C. Kwon

2005-11-01T23:59:59.000Z

16

One-dimensional hybrid-direct kinetic simulation of the discharge plasma in a Hall thruster  

SciTech Connect

In order to model the non-equilibrium plasma within the discharge region of a Hall thruster, the velocity distribution functions (VDFs) must be obtained accurately. A direct kinetic (DK) simulation method that directly solves the plasma Boltzmann equation can achieve better resolution of VDFs in comparison to particle simulations, such as the particle-in-cell (PIC) method that inherently include statistical noise. In this paper, a one-dimensional hybrid-DK simulation, which uses a DK simulation for heavy species and a fluid model for electrons, is developed and compared to a hybrid-PIC simulation. Time-averaged results obtained from the hybrid-DK simulation are in good agreement with hybrid-PIC results and experimental data. It is shown from a comparison of using a kinetic simulation and solving the continuity equation that modeling of the neutral atoms plays an important role for simulations of the Hall thruster discharge plasma. In addition, low and high frequency plasma oscillations are observed. Although the kinetic nature of electrons is not resolved due to the use of a fluid model, the hybrid-DK model provides spatially and temporally well-resolved plasma properties and an improved resolution of VDFs for heavy species with less statistical noise in comparison to the hybrid-PIC method.

Hara, Kentaro; Boyd, Iain D. [University of Michigan, Ann Arbor, Michigan 48109 (United States); Kolobov, Vladimir I. [CFD Research Corporation, Huntsville, Alabama 35805 (United States)

2012-11-15T23:59:59.000Z

17

Kinetics of the direct electric heating of a stationary bed of activated charcoal  

SciTech Connect

Direct electric heating by passing an electrical current directly through a bed of adsorbent may prove to be an efficient means of regenerating activated charcoal in continuous and batch adsorption processes. Obvious advantages of this type of regeneration are its almost complete lack of inertia, which makes it possible to reduce the number and dimensions of the adsorbers, and its highly efficient use of energy due to the small number of steps in the conversion of the energy, as well as the reduction of heat losses involved in warming the structure and making up for losses to the surroundings. The authors consider the kinetics of direct electric heating of a stationary bed of activated charcoal not containing adsorbed substances.

Marfin, M.N.; Shumyatskii, Yu.I.

1987-08-20T23:59:59.000Z

18

Airborne Spectral Measurements of Ocean Directional Reflectance  

Science Conference Proceedings (OSTI)

The Cloud Absorption Radiometer (CAR) was flown aboard the University of Washington Convair 580 (CV-580) research aircraft during the Chesapeake Lighthouse and Aircraft Measurements for Satellites (CLAMS) field campaign and obtained measurements ...

Charles K. Gatebe; Michael D. King; Alexei I. Lyapustin; G. Thomas Arnold; Jens Redemann

2005-04-01T23:59:59.000Z

19

On Measuring the Terms of the Turbulent Kinetic Energy Budget from an AUV  

Science Conference Proceedings (OSTI)

The terms of the steady-state, homogeneous turbulent kinetic energy budgets are obtained from measurements of turbulence and fine structure from the small autonomous underwater vehicle (AUV) Remote Environmental Measuring Units (REMUS). The ...

Louis Goodman; Edward R. Levine; Rolf G. Lueck

2006-07-01T23:59:59.000Z

20

Microprocessor Field Impactometer Calibration: Do We Measure Drops’ Momentum or Their Kinetic Energy?  

Science Conference Proceedings (OSTI)

This study presents the construction and calibration of a low-cost piezoelectric microprocessor impactometer designed for the field measurements of the rainfall kinetic energy (KE) flux. Its precise calibration was performed in laboratory ...

Pawe? Licznar; Janusz ?omotowski; S?awomir B?o?ski; Grzegorz J. Ciach

2008-05-01T23:59:59.000Z

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


21

Direct Solar Spectral Irradiance Measurements and Updated Simple Transmittance Models  

Science Conference Proceedings (OSTI)

A set of 509 direct solar irradiance spectra, carefully measured over one year, is checked against spectral irradiances computed from five updated transmittance models. The wavelengths under investigation range from 290 to 900 nm, with a 5- or 10-...

A. de La Casinière; A. I. Bokoye; T. Cabot

1997-05-01T23:59:59.000Z

22

Measurement of Directional Wave Spectra Using Aircraft Laser Altimeters  

Science Conference Proceedings (OSTI)

A remote sensing method to measure directional oceanic surface waves by three laser altimeters on the NOAA LongEZ aircraft is investigated. To examine feasibility and sensitivity of the wavelet analysis method to various waves, aircraft motions, ...

J. Sun; S. P. Burns; D. Vandemark; M. A. Donelan; L. Mahrt; Timothy L. Crawford; T. H. C. Herbers; G. H. Crescenti; J. R. French

2005-07-01T23:59:59.000Z

23

Direct photons measured by the PHENIX experiment at RHIC  

E-Print Network (OSTI)

Results from the PHENIX experiment at RHIC on direct photon production in p+p, d+Au, and Au+Au collisions at sqrt(s_NN) = 200 GeV are presented. In p+p collisions, direct photon production at high p_T behaves as expected from perturbative QCD calculations. The p+p measurement serves as a baseline for direct photon production in Au+Au collisions. In d+Au collisions, no effects of cold nuclear matter are found within the large uncertainty of the measurement. In Au+Au collisions, the production of high p_T direct photons scales as expected for particle production in hard scatterings. This supports jet quenching models, which attribute the suppression of high p_T hadrons to the energy loss of fast partons in the medium produced in the collision. Low p_T direct photons, measured via e+e- pairs with small invariant mass, are possibly related to the production of thermal direct photons.

Stefan Bathe; for the PHENIX Collaboration

2006-09-19T23:59:59.000Z

24

Direct photon-charged hadron coincidence measurements in STAR  

E-Print Network (OSTI)

The multiplicities of charged particle with transverse momentum (3 $direct photons and $\\pi^{0}$ of high transverse momentum (8 $direct $\\gamma$ are extracted. An agreement is observed between the measured suppression for direct $\\gamma$-trigger associated-particle yields in $Au+Au$ compared to that in $p+p$ and theoretical calculations, although the uncertainties are large. Within the current uncertainties, the suppression is similar to the previously observed suppression in single-particle yields as well as in hadron-triggered associated-particle yields.

Ahmed M. Hamed

2009-05-26T23:59:59.000Z

25

Direct photons at low $p_{T}$ measured in PHENIX  

E-Print Network (OSTI)

Direct photon spectra measured at small $p_T$ in p+p, d+Au and Au+Au collisions at $\\sqrt{s_{NN}}=200$ GeV are presented. Several measurement techniques including statistical subtraction, tagging, and internal and external conversion were applied and found to produce consistent results. The p+p and d+Au results are found to be in very good agreement with pQCD predictions over the entire $p_T$ range. No excess of direct photons in Au+Au collisions with respect to binary scaled d+Au data is observed within systematic errors.

D. Peressounko

2007-02-12T23:59:59.000Z

26

Direct gas in mud measurement at the well site  

Science Conference Proceedings (OSTI)

A patented process developed by Datalog provides a direct quantitative gas measurement from the drilling fluid, eliminates the gas trap (degasser) and the conversion to gas-in-air measurements associated with traditional gas detection methods. Quantitative hydrocarbon gas measurement can be performed at the wellsite through the use of this gas detection system called GasWizard. This is achieved with a passive device containing a gas permeable membrane that is immersed in the drilling fluid. The device extracts a gas sample that is directly proportional to the actual gas concentration in the drilling fluid. Through this simple process, the gas measurement is equally effective in conventional water or oil-base drilling muds or in underbalanced drilling fluids such as foam, air or nitrogen.

Hawker, D. [Datalog, Calgary, Alberta (Canada)

1999-09-01T23:59:59.000Z

27

Direct measurement of the negative-kaon form factor  

Science Conference Proceedings (OSTI)

The electromagnetic form factor of the negative kaon has been measured by direct scattering of 250 GeV/c kaons from the stationary electrons of a liquid-hydrogen target. The deviation of the measured elastic scattering cross section from the point cross section may be characterized by a root-mean-square kaon radius of /sup 1/2/=0.53 +- 0.05 fm.

Dally, E.B.; Hauptman, J.M.; Kubic, J.; Stork, D.H.; Watson, A.B.; Guzik, Z.; Nigmanov, T.S.; Riabtsov, V.D.; Tsyganov, E.N.; Vodopianov, A.S.; Beretvas, A.; Grigorian, A.; Tompkins, J.C.; Toohig, T.E.; Wehmann, A.A.; Poirier, J.A.; Rey, C.A.; Volk, J.T.; Rapp, P.D.; Shepard, P.F.

1980-07-28T23:59:59.000Z

28

Scanning delay generator for measurement of kinetic decays using laser-induced fluorescence techniques  

SciTech Connect

An electronic device is described which generates a delayed pulse, where the delay is increased in a step-like manner. This device finds application in the measurement of kinetic decays, particularly when laser-induced fluorescent (LIF) detection of the decaying species is used. The circuit uses 15 low-power Schottky TTL chips and is contained within a dual width NIM module.

Halpern, J.B.; Towns, T.G.

1982-11-01T23:59:59.000Z

29

Coalescence kinetics in surfactant stabilized emulsions: Evolution equations from direct numerical simulations  

Science Conference Proceedings (OSTI)

Lattice Boltzmann simulations were used to study the coalescence kinetics in emulsions with amphiphilic surfactant, under neutrally buoyant conditions, and with a significant kinematic viscosity contrast between the phases (emulating water in oil emulsions). The 3D simulation domain was large enough (256 3rd power -- 10 7th power grid points) to obtain good statistics with droplet numbers ranging from a few thousand at early times to a few hundred near equilibrium. Increased surfactant contents slowed down the coalescence rate between droplets due to the Gibbs-Marangoni effect, and the coalescence was driven by a quasi-turbulent velocity field. The kinetic energy decayed at a relatively slow rate at early times, due to conversion of interfacial energy to kinetic energy in the flow during coalescence. Phenomenological, coupled differential equations for the mean droplet diameter D(t) and the number density nd(t) were obtained from the simulation data and from film draining theories. Local (in time) power law exponents for the growth of the mean diameter (and for the concomitant decrease of nd) were established in terms of the instantaneous values of the kinetic energy, coalescence probability, Gibbs elasticity, and interfacial area. The model studies indicated that true power laws for the growth of the droplet size and decrease of the number of droplets with time may not be justified, since the exponents derived using the phenomenological model were time dependent. In contrast to earlier simulation results for symmetric blends with surfactant, we found no evidence for stretched logarithmic scaling of the formD -- [ln (ct)]a for the morphology length, or exponential scalings associated with arrested growth, on the basis of the phenomenological model.

R. Skartlien; E. Sollum; A. Akselsen; P. Meakin; B. Grimes; J. Sjoblom

2012-12-01T23:59:59.000Z

30

NETL: Emissions Characterization - Direct Measurement of Mercury Reactions  

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

Direct Measurement of Mercury Reactions in Coal Power Plant Plumes: Pleasant Prairie Plant Direct Measurement of Mercury Reactions in Coal Power Plant Plumes: Pleasant Prairie Plant Under DOE-NETL Cooperative Agreement DE-FC26-03NT41724, EPRI, in collaboration with Frontier Geosciences and the University of North Dakota Energy and Environmental Research Center (EERC), will perform precise in-stack and in-plume sampling of mercury emitted from the stack of WE Energies' Pleasant Prairie coal-fired power plant near Kenosha, Wisconsin. The overall objective of the project is to clarify the role, rates and end result of chemical transformations that may occur to mercury that has been emitted from elevated stacks of coal-fired electric power plants. This information is critical in determining the role of coal-fired plants in mercury deposition and in developing cost-effective, environmentally sound policies and strategies for reducing the adverse environmental effects of mercury.

31

Direct Photon-Hadron Correlations Measured with PHENIX  

E-Print Network (OSTI)

Direct photon-hadron correlations greatly improve our ability to perform jet tomography in heavy-ion collisions because the momentum of the direct photon can be used to constrain the initial momentum of the opposing jet. By comparing the spectrum of away-side hadrons observed in heavy ion collisions to the spectrum seen in nucleon collisions we can quantify the medium modification to the fragmentation function due to energy loss of the away-side parton. High $p_{T}$ direct photon-hadron correlations have been measured with the PHENIX detector using a statistical subtraction method to remove the photon contribution from meson decays. The increased integrated luminosity in the most recent Au+Au RHIC run at $\\sqrt{s_{NN}}$ = 200 GeV provides substantially improved statistical precision and enhances the kinematic reach. These measurements are compared to PHENIX p+p results and several theoretical models of energy loss. In addition, we compare direct photon-hadron and $\\pi^{0}$-hadron correlations.

Megan Connors; for the PHENIX Collaboration

2009-07-27T23:59:59.000Z

32

BPA experience in the direct measurement of power system dynamics  

Science Conference Proceedings (OSTI)

Sustained growth of a large power system tends to make the model-based planning of system expansions and operations increasingly difficult. This paper presents a BPA perspective on procedures for extracting supplemental information for the power system itself. These procedures involve disturbance analysis, ambient measurements, and direct tests. Results shown for the western U.S. power system include a response model derived from a recent test energization of BPA's 1400 MW dynamic brake. The model construction illustrated combined use of Fourier analysis, Prony analysis, and optimal fitting to measured frequency response.

Hauer, J.F. (Bonneville Power Administration, Portland, OR (United States))

1990-01-01T23:59:59.000Z

33

Kinetic measurement and prediction of the hydrogen outgassing from the polycrystalline LiH/LiOH system  

DOE Green Energy (OSTI)

In this report, we present the use of temperature programmed reaction/decomposition (TPR) in the isoconversion mode to measure outgassing kinetics and to make kinetic prediction concerning hydrogen release from the polycrystalline LiH/LiOH system in the absence of any external H{sub 2}O source.

Dinh, L N; Grant, D M; Schildbach, M A; Smith, R A; Leckey, J H; Siekhaus, W J; Balazs, B; McLean II, W

2005-03-09T23:59:59.000Z

34

Solar Model Parameters and Direct Measurements of Solar Neutrino Fluxes  

E-Print Network (OSTI)

We explore a novel possibility of determining the solar model parameters, which serve as input in the calculations of the solar neutrino fluxes, by exploiting the data from direct measurements of the fluxes. More specifically, we use the rather precise value of the $^8B$ neutrino flux, $\\phi_B$ obtained from the global analysis of the solar neutrino and KamLAND data, to derive constraints on each of the solar model parameters on which $\\phi_B$ depends. We also use more precise values of $^7Be$ and $pp$ fluxes as can be obtained from future prospective data and discuss whether such measurements can help in reducing the uncertainties of one or more input parameters of the Standard Solar Model.

Abhijit Bandyopadhyay; Sandhya Choubey; Srubabati Goswami; S. T. Petcov

2006-08-30T23:59:59.000Z

35

Tonehole radiation directivity: A comparison of theory to measurements  

E-Print Network (OSTI)

Measurements have been conducted in an anechoic chamber for comparison to current linear acoustic theory for radiation directivity from a cylindrical pipe with toneholes. Time-delay spectrometry using an exponentially swept sine signal was employed to determine impulse responses at points external to the experimental air column. This technique is effective in clearly isolating nonlinear artifacts from the desired linear system response along the time axis, allowing the use of a strong driving signal without fear of nonlinear distortion. The experimental air column was positioned through a wall conduit into the anechoic chamber such that the driver and pipe input were located outside the chamber while the open pipe end and toneholes were inside the chamber, effectively isolating the source from the pickup. Measured results are compared to both frequency-domain, transmissionnetwork simulations, as well as time-domain, digital waveguide calculations. 1

Gary P. Scavone; Matti Karjalainen

2002-01-01T23:59:59.000Z

36

Direct Evidence of an Oceanic Inverse Kinetic Energy Cascade from Satellite Altimetry  

Science Conference Proceedings (OSTI)

Sea surface height measurements from satellites reveal the turbulent properties of the South Pacific Ocean surface geostrophic circulation, both supporting and challenging different aspects of geostrophic turbulence theory. A near-universal shape ...

Robert B. Scott; Faming Wang

2005-09-01T23:59:59.000Z

37

Direct Measurements of Pore Fluid Density by Vibrating Tube Densimetry  

Science Conference Proceedings (OSTI)

The densities of pore-confined fluids were measured for the first time by means of a vibrating tube method. Isotherms of total adsorption capacity were measured directly making the method complementary to the conventional gravimetric or volumetric/piezometric adsorption techniques, which yield the excess adsorption (the Gibbsian surface excess). A custom-made high-pressure, high-temperature vibrating tube densimeter (VTD) was used to measure the densities of subcritical and supercritical propane (between 35 C and 97 C) and supercritical carbon dioxide (between 32 C and 50 C) saturating hydrophobic silica aerogel (0.2 g/cm3, 90% porosity) synthesized inside Hastelloy U-tubes. Additionally, excess adsorption isotherms for supercritical CO2 and the same porous solid were measured gravimetrically using a precise magnetically-coupled microbalance. Pore fluid densities and total adsorption isotherms increased monotonically with increasing density of the bulk fluid, in contrast to excess adsorption isotherms, which reached a maximum at a subcritical density of the bulk fluid, and then decreased towards zero or negative values at supercritical densities. Compression of the confined fluid significantly beyond the density of the bulk liquid at the same temperature was observed at subcritical temperatures. The features of the isotherms of confined fluid density are interpreted to elucidate the observed behavior of excess adsorption. The maxima of excess adsorption were found to occur below the critical density of the bulk fluid at the conditions corresponding to the beginning of the plateau of total adsorption, marking the end of the transition of pore fluid to a denser, liquid-like pore phase. The results for propane and carbon dioxide showed similarity in the sense of the principle of corresponding states. No measurable effect of pore confinement on the liquid-vapor critical point was found. Quantitative agreement was obtained between excess adsorption isotherms determined from VTD total adsorption results and those measured gravimetrically at the same temperature, confirming the validity of the vibrating tube measurements. Vibrating tube densimetry was demonstrated as a novel experimental approach capable of providing the average density of pore-confined fluids.

Gruszkiewicz, Miroslaw {Mirek} S [ORNL; Rother, Gernot [ORNL; Wesolowski, David J [ORNL; Cole, David R [ORNL; Wallacher, Dirk [Helmholtz-Zentrum Berlin

2012-01-01T23:59:59.000Z

38

Direct measurements of the ionization profile in krypton helicon plasmas  

SciTech Connect

Helicons are efficient plasma sources, capable of producing plasma densities of 10{sup 19} m{sup -3} with only 100 s W of input rf power. There are often steep density gradients in both the neutral density and plasma density, resulting in a fully ionized core a few cm wide surrounded by a weakly ionized plasma. The ionization profile is usually not well known because the neutral density is typically inferred from indirect spectroscopic measurements or from edge pressure gauge measurements. We have developed a two photon absorption laser induced fluorescence (TALIF) diagnostic capable of directly measuring the neutral density profile. We use TALIF in conjunction with a Langmuir probe to measure the ionization fraction profile as a function of driving frequency, magnetic field, and input power. It is found that when the frequency of the driving wave is greater than a critical frequency, f{sub c} Almost-Equal-To 3f{sub lh}, where f{sub lh} is the lower hybrid frequency at the antenna, the ionization fraction is small (0.1%) and the plasma density low (10{sup 17} m{sup -3}). As the axial magnetic field is increased, or, equivalently, the driving frequency decreased, a transition is observed. The plasma density increases by a factor of 10 or more, the plasma density profile becomes strongly peaked, the neutral density profile becomes strongly hollow, and the ionization fraction in the core approaches 100%. Neutral depletion in the core can be caused by a number of mechanisms. We find that in these experiments the depletion is due primarily to plasma pressure and neutral pumping.

Magee, R. M.; Galante, M. E.; McCarren, D. W.; Scime, E. E. [Department of Physics, West Virginia University, Morgantown, West Virginia 26506 (United States); Gulbrandsen, N. [Department of Physics and Technology, Faculty of Science, University of Tromso, N-9037 Tromso (Norway)

2012-12-15T23:59:59.000Z

39

Direct measures of mechanical energy for knife mill size reduction  

Science Conference Proceedings (OSTI)

Lengthy straw/stalk of biomass may not be directly fed into grinders such as hammer mills and disc refiners. Hence, biomass needs to be preprocessed using coarse grinders like a knife mill to allow for efficient feeding in refiner mills without bridging and choking. Size reduction mechanical energy was directly measured for switchgrass (Panicum virgatum L.), wheat straw (Triticum aestivum L.), and corn stover (Zea mays L.) in an instrumented knife mill. Direct power inputs were determined for different knife mill screen openings from 12.7 to 50.8 mm, rotor speeds between 250 and 500 rpm, and mass feed rates from 1 to 11 kg/min. Overall accuracy of power measurement was calculated to be 0.003 kW. Total specific energy (kWh/Mg) was defined as size reduction energy to operate mill with biomass. Effective specific energy was defined as the energy that can be assumed to reach the biomass. The difference is parasitic or no-load energy of mill. Total specific energy for switchgrass, wheat straw, and corn stover chopping increased with knife mill speed, whereas, effective specific energy decreased marginally for switchgrass and increased for wheat straw and corn stover. Total and effective specific energy decreased with an increase in screen size for all the crops studied. Total specific energy decreased with increase in mass feed rate, but effective specific energy increased for switchgrass and wheat straw, and decreased for corn stover at increased feed rate. For knife mill screen size of 25.4 mm and optimum speed of 250 rpm, optimum feed rates were 7.6, 5.8, and 4.5 kg/min for switchgrass, wheat straw, and corn stover, respectively, and the corresponding total specific energies were 7.57, 10.53, and 8.87 kWh/Mg and effective specific energies were 1.27, 1.50, and 0.24 kWh/Mg for switchgrass, wheat straw, and corn stover, respectively. Energy utilization ratios were calculated as 16.8%, 14.3%, and 2.8% for switchgrass, wheat straw, and corn stover, respectively. These data will be useful for preparing the feed material for subsequent fine grinding operations and designing new mills.

Bitra, V.S.P. [University of Tennessee; Womac, A.R. [University of Tennessee; Igathinathane, C. [Mississippi State University (MSU); Miu, P.I [University of Tennessee; Yang, Y.T. [University of Tennessee; Smith, D.R. [University of Tennessee; Chevanan, Nehru [University of Tennessee; Sokhansanj, Shahabaddine [ORNL

2009-08-01T23:59:59.000Z

40

Measured and projected performance of plasma direct converters  

DOE Green Energy (OSTI)

Test results from two plasma direct converters and their predicted cost and performance on tandem mirror fusion reactors are present. The tests were done at high power density (approx. 70 W/cm/sup 2/) in steady state to simulate the predicted conditions in a reactor. A single stage unit and a two-stage unit of the Venetian blind type were tested at up to 100 kV and 6 kW for a total time of about 80 hours. Measured efficiencies, when projected to a reactor, are typically about 50% for a single stage unit and 60 to 70% for a two-stage unit, depending on the energy distribution of the ions, the degree of subdivision of the collectors, and on the gas pressure. The high ambipolar potential in tandem mirror devices makes this good efficiency possible. When radiatively cooled grids are used, the incident power density is limited to about 100 W/cm/sup 2/ by the thermionic emission of electrons.

Barr, W.L.; Moir, R.W.

1981-10-22T23:59:59.000Z

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


41

Kinetic Energy Budgets of a Subtropical Squall Line Determined from TAMEX Dual-Doppler Measurements  

Science Conference Proceedings (OSTI)

Dual-Doppler data collected during the Taiwan Area Mesoscale Experiment (TAMEX) are used to study the kinetic energy balance of a subtropical squall line over the Taiwan Straits. Values of each term in the kinetic energy budget equation are ...

Yeong-Jer Lin; Hsi Shen; Robert W. Pasken

1991-11-01T23:59:59.000Z

42

n-Butane: Ignition delay measurements at high pressure and detailed chemical kinetic simulations  

Science Conference Proceedings (OSTI)

Ignition delay time measurements were recorded at equivalence ratios of 0.3, 0.5, 1, and 2 for n-butane at pressures of approximately 1, 10, 20, 30 and 45 atm at temperatures from 690 to 1430 K in both a rapid compression machine and in a shock tube. A detailed chemical kinetic model consisting of 1328 reactions involving 230 species was constructed and used to validate the delay times. Moreover, this mechanism has been used to simulate previously published ignition delay times at atmospheric and higher pressure. Arrhenius-type ignition delay correlations were developed for temperatures greater than 1025 K which relate ignition delay time to temperature and concentration of the mixture. Furthermore, a detailed sensitivity analysis and a reaction pathway analysis were performed to give further insight to the chemistry at various conditions. When compared to existing data from the literature, the model performs quite well, and in several instances the conditions of earlier experiments were duplicated in the laboratory with overall good agreement. To the authors' knowledge, the present paper presents the most comprehensive set of ignition delay time experiments and kinetic model validation for n-butane oxidation in air. (author)

Healy, D.; Curran, H.J. [Combustion Chemistry Centre, School of Chemistry, NUI Galway (Ireland); Donato, N.S.; Aul, C.J.; Petersen, E.L. [Department of Mechanical Engineering, Texas A and M University, College Station, TX (United States); Zinner, C.M. [Mechanical, Materials and Aerospace Engineering, University of Central Florida, Orlando, FL (United States); Bourque, G. [Rolls-Royce Canada Limited, 9500 Cote de Liesse, Lachine, Quebec, H8T 1A2 (Canada)

2010-08-15T23:59:59.000Z

43

The Measure of Human Error: Direct and Indirect Performance Shaping Factors  

Science Conference Proceedings (OSTI)

The goal of performance shaping factors (PSFs) is to provide measures to account for human performance. PSFs fall into two categories—direct and indirect measures of human performance. While some PSFs such as “time to complete a task” are directly measurable, other PSFs, such as “fitness for duty,” can only be measured indirectly through other measures and PSFs, such as through fatigue measures. This paper explores the role of direct and indirect measures in human reliability analysis (HRA) and the implications that measurement theory has on analyses and applications using PSFs. The paper concludes with suggestions for maximizing the reliability and validity of PSFs.

Ronald L. Boring; Candice D. Griffith; Jeffrey C. Joe

2007-08-01T23:59:59.000Z

44

Photo-oxidation of Ge Nanocrystals: Kinetic Measurements by InSitu Raman Spectroscopy  

SciTech Connect

Ge nanocrystals are formed in silica by ion beam synthesis and are subsequently exposed by selective HF etching of the silica. Under ambient conditions, the exposed nanocrystals are stable after formation of a protective native oxide shell of no more than a few monolayers. However, under visible laser illumination at room temperature and in the presence of O{sub 2}, the nanocrystals rapidly oxidize. The oxidation rate was monitored by measuring the Raman spectra of the Ge nanocrystals in-situ. The intensity ratio of the anti-Stokes to the Stokes line indicated that no significant laser-induced heating of illuminated nanocrystals occurs. Therefore, the oxidation reaction rate enhancement is due to a photo-chemical process. The oxidation rate varies nearly linearly with the logarithm of the laser intensity, and at constant laser intensity the rate increases with increasing photon energy. These kinetic measurements, along with the power dependencies, are described quantitatively by an electron active oxidation mechanism involving tunneling of optically excited electrons through the forming oxide skin and subsequent transport of oxygen ions to the Ge nanocrystal surface.

Sharp, I.D.; Xu, Q.; Yuan, C.W.; Beeman, J.W.; Ager III, J.W.; Chrzan, D.C.; Haller, E.E.

2006-11-22T23:59:59.000Z

45

Direct measurements improve estimates of dairy greenhouse-gas emissions  

E-Print Network (OSTI)

small quantity of Greenhouse gases measured enteric nitrousSC, Pain BF. 1994. Greenhouse gas emissions from intensiveE, Brose G. 2001. Greenhouse gas emissions from animal house

Mitloehner, Frank M; Sun, Huawei; Karlik, John F

2009-01-01T23:59:59.000Z

46

A Comparison of Directional Buoy and Fixed Platform Measurements Of Pacific Swell  

Science Conference Proceedings (OSTI)

The performance of the Datawell Directional Waverider and the National Data Buoy Center (NDBC) 3-m discus buoy, widely used to measure the directional properties of surface gravity waves, are evaluated through comparisons to an array of six ...

W. C. O'Reilly; T. H. C. Herbers; R. J. Seymour; R. T. Guza

1996-02-01T23:59:59.000Z

47

Autoignition measurements and a validated kinetic model for the biodiesel surrogate, methyl butanoate  

Science Conference Proceedings (OSTI)

The autoignition of methyl butanoate has been studied at 1 and 4 atm in a shock tube over the temperature range 1250-1760 K at equivalence ratios of 1.5, 1.0, 0.5, and 0.25 at fuel concentrations of 1.0 and 1.5%. These measurements are complemented by autoignition data from a rapid compression machine over the temperature range 640-949 K at compressed gas pressures of 10, 20, and 40 atm and at varying equivalence ratios of 1.0, 0.5, and 0.33 using fuel concentrations of 1.59 and 3.13%. The autoignition of methyl butanoate is observed to follow Arrhenius-like temperature dependence over all conditions studied. These data, together with speciation data reported in the literature in a flow reactor, a jet-stirred reactor, and an opposed-flow diffusion flame, were used to produce a detailed chemical kinetic model. It was found that the model correctly simulated the effect of change in equivalence ratio, fuel fraction, and pressure for shock tube ignition delays. The agreement with rapid compression machine ignition delays is less accurate, although the qualitative agreement is reasonable. The model reproduces most speciation data with good accuracy. In addition, the important reaction pathways over each regime have been elucidated by both sensitivity and flux analyses. (author)

Dooley, S.; Curran, H.J.; Simmie, J.M. [Combustion Chemistry Centre, National University of Ireland, Galway (Ireland)

2008-04-15T23:59:59.000Z

48

Measurement of Turbulent Kinetic Energy Dissipation Rate with a Lagrangian Float  

Science Conference Proceedings (OSTI)

This study tests the ability of a neutrally buoyant float to estimate the dissipation rate of turbulent kinetic energy ? from its vertical acceleration spectrum using an inertial subrange method. A Lagrangian float was equipped with a SonTek ...

Ren-Chieh Lien; Eric A. D'Asaro

2006-07-01T23:59:59.000Z

49

Oxidation kinetics of methylphosphonic acid in supercritical water : experimental measurements and model development  

E-Print Network (OSTI)

(cont.) at well-defined operating conditions and to develop. both microscopic and macroscopic models, ranging from regressed global models to an elementary reaction mechanism, to quantify MPA oxidation kinetics in supercritical ...

Sullivan, Patricia A. (Patricia Ann), 1978-

2004-01-01T23:59:59.000Z

50

Dynamic Response of the Fine Wire Psychrometer for Direct Measurement of Water Vapor Flux  

Science Conference Proceedings (OSTI)

For the measurement of humidity fluctuation in the atmospheric boundary layer, a wet- and dry-bulb ther-mocouple psychrometer has been used traditionally. However, in the direct measurement of water vapor flux with the eddy correlation method, ...

Osamu Tsukamoto

1986-09-01T23:59:59.000Z

51

Field Comparisons of Direct and Component Measurements of Net Radiation under Clear Skies  

Science Conference Proceedings (OSTI)

Accurate measurements of net radiation are basic to all studies of the surface energy budget. In preparation for an energy budget experiment significant differences were found between direct and component measurement of net radiation, which ...

Claude E. Duchon; Gregory E. Wilk

1994-02-01T23:59:59.000Z

52

The Quest for K?—Preliminary Results from Direct Measurements of Turbulent Fluxes in the Ocean  

Science Conference Proceedings (OSTI)

Simultaneous measurements of vertical velocity fluctuations, w?, and temperature fluctuations, T?, on scales of three-dimensional turbulence yield a direct measure of the turbulent heat flux, Jq. The scales contributing most significantly to Jq ...

J. N. Moum

1990-12-01T23:59:59.000Z

53

DIRECT MEASUREMENT OF HEAT FLUX FROM COOLING LAKE THERMAL IMAGERY  

SciTech Connect

Laboratory experiments show a linear relationship between the total heat flux from a water surface to air and the standard deviation of the surface temperature field, {sigma}, derived from thermal images of the water surface over a range of heat fluxes from 400 to 1800 Wm{sup -2}. Thermal imagery and surface data were collected at two power plant cooling lakes to determine if the laboratory relationship between heat flux and {sigma} exists in large heated bodies of water. The heat fluxes computed from the cooling lake data range from 200 to 1400 Wm{sup -2}. The linear relationship between {sigma} and Q is evident in the cooling lake data, but it is necessary to apply band pass filtering to the thermal imagery to remove camera artifacts and non-convective thermal gradients. The correlation between {sigma} and Q is improved if a correction to the measured {sigma} is made that accounts for wind speed effects on the thermal convection. Based on more than a thousand cooling lake images, the correlation coefficients between {sigma} and Q ranged from about 0.8 to 0.9.

Garrett, A; Eliel Villa-Aleman, E; Robert Kurzeja, R; Malcolm Pendergast, M; Timothy Brown, T; Saleem Salaymeh, S

2007-12-19T23:59:59.000Z

54

Beam Energy Dependence of Directed and Elliptic Flow Measurement from the STAR Experiment  

E-Print Network (OSTI)

Measurements of anisotropic flow in heavy-ion collisions provide insight into the early stage of the system's evolution. This proceedings presents directed and elliptic flow for Au+Au collisions at 39, 11.5 and 7.7 GeV, and for Cu+Cu at 22.4 GeV, measured in the STAR Experiment at RHIC. Differential measurements of directed and elliptic flow of charged particles as a function of centrality, transverse momentum and pseudorapidity are discussed.

Yadav Pandit

2011-09-13T23:59:59.000Z

55

Modified Fragmentation Function in Heavy Ion Collisions at RHIC via Direct photon-Jet Measurements  

E-Print Network (OSTI)

The presented results are the first measurements at RHIC for direct $\\gamma$-charged hadron azimuthal correlations in heavy ion collisions. We use these correlations to study the color charge density of the medium through the medium-induced modification of high-p$_T$ parton fragmentation. Azimuthal correlations of direct photons at high transverse energy (8 $direct photons and photons from the decays of high p$_T$ $\\pi^{0}$. The per-trigger away-side yield of direct $\\gamma$ is smaller than from $\\pi^{0}$ trigger at the same centrality class. Within the current uncertainty the I$_{CP}$ of direct $\\gamma$ and $\\pi^{0}$ are similar.

Ahmed M. Hamed

2008-09-08T23:59:59.000Z

56

THE EFFECT OF CIRCUMSOLAR RADIATION ON THE ACCURACY OF PYRHELIOMETER MEASUREMENTS OF THE DIRECT SOLAR RADIATION  

E-Print Network (OSTI)

Diffuse, and Total Solar Radiation," Solar Energy, vol. 4,r Presented at the Solar Radiation workshop of Solar Rising,MEASUREMENTS OF THE DIRECT SOLAR RADIATION D. Grether, D.

Grether, D.

2012-01-01T23:59:59.000Z

57

A Technique for Deducing Wind Direction from Satellite Microwave Measurements of Wind Speed  

Science Conference Proceedings (OSTI)

A technique is presented to deduce wind direction from satellite microwave measurements of wind speed information. The technique, based on simple Ekman boundary layer dynamics, makes use of surface pressure fields routinely analyzed at the ...

Tsann-wang Yu

1987-09-01T23:59:59.000Z

58

On the Results of Measurements of the Direct Sun Radiation Flux...  

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

On the Results of Measurements of the Direct Sun Radiation Flux by Actinometer and of Maximal Polarization of Sky Brightness in the Solar Almucantar A. Kh. Shukurov, K. A....

59

Exploration of jet energy loss via direct $?$-charged particle azimuthal correlation measurements  

E-Print Network (OSTI)

The multiplicities of charged particles azimuthally associated with direct photons and $\\pi^{0}$ have been measured for Au+Au, p+p, and d+Au collisions at $\\sqrt{s_{NN}}$ = 200 GeV in the STAR experiment. Charged particles with transverse momentum 0.5 $direct photons and $\\pi^{0}$ of high transverse momentum 8 $direct $\\gamma$ in central Au+Au relative to p+p and d+Au are similar and constant with direct photon fractional energy $z_{T}$ ($z_{T}=p_{T}^{h^{\\pm}}/p_{T}^{\\gamma}$). The measured suppressions of the associated yields with direct $\\gamma$ are comparable to those with $\\pi^{0}$. The data are compared to theoretical predictions.

A. M. Hamed

2009-07-26T23:59:59.000Z

60

Direct photons in Au+Au collisions measured with the PHENIX detector at RHIC  

E-Print Network (OSTI)

A major goal of experiments in heavy-ion physics is the characterization of the quark gluon plasma (QGP) produced in the collision of heavy ions at high energy. Direct photons are a particularly good probe of the produced medium because they do not interact strongly and so can escape the medium unmodified, carrying information about when the photon was produced. It is expected that direct photon contributions from different sources (QGP radiation, hard scattering, hadron gas radiation) dominate at different transverse momentum ranges. Low momentum direct photons are dominated by thermal radiation (both from the QGP and hadron gas), while high momentum direct photons dominantly come from hard parton scatterings in the initial collision. We present a summary of techniques to measure direct photons with the PHENIX detector, with a focus on low momentum direct photons through their external conversion to dilepton pairs.

Richard Petti

2011-07-27T23:59:59.000Z

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


61

CAD and Graphics: Design and CAD-directed inspection planning of laser-guided measuring robot  

Science Conference Proceedings (OSTI)

A miniature laser-guided measuring robot (LGMR) has been developed based on a novel theory ''laser beam moving and spherical mounted retro-reflector (SMR) tracking'' instead of the traditional method ''SMR moving and laser beam tracking''. A systematic ... Keywords: CAD-directed, Design, Inspection planning, Laser-guided measuring robot (LGMR)

Wanli Liu; Xinghua Qu; Jianfei Ouyang; Zhankui Wang

2008-12-01T23:59:59.000Z

62

Kinetic solvation pressure: a measure of environmental effects on reaction rates. 1. Application to hydrophobic systems  

SciTech Connect

A quantity termed kinetic solvation pressure is defined as (/partial derivative//Delta/G/sup /double dagger////partial derivative//anti/V)/sub T/, where /anti/V is the reactant molar volume. It is identified with the difference in the amount of isothermal work, per unit volume expansion necessary to create a solvation cavity in a particular medium, upon transition-state complex formation. The quantity was evaluated for the hydrolysis of carboxylic esters mediated by different hydrophobic catalysts and was found to be equal to +26 J cm/sup /minus/3/ for the acid-catalyzed hydrolysis of n-alkyl acetates in water solvent; but it becomes negative when macro- or supramolecular acids were used as catalysts: /minus/16 J cm/sup /minus/3/ for Dowex 50W-X2, /minus/43J cm/sup /minus/3/ for poly(styrenesulfonic acid), /minus/64 J cm/sup /minus/3/ for dodecylsulfuric acid micelles. These results suggest the action of hydrophobic forces in enhancing the catalytic power of the supermolecules, relative to aqueous hydrogen ion. No such effect is seen in aqueous acetone or when more hydrophilic acetates are used as substrates. Kinetic solvation pressure for enzyme-catalyzed ester hydrolysis is five times more negative than for the resin system, indicating the full action of hydrophobic forces in the catalytic process.

Mata-Segreda, J.F.

1988-08-31T23:59:59.000Z

63

Isobutane ignition delay time measurements at high pressure and detailed chemical kinetic simulations  

SciTech Connect

Rapid compression machine and shock-tube ignition experiments were performed for real fuel/air isobutane mixtures at equivalence ratios of 0.3, 0.5, 1, and 2. The wide range of experimental conditions included temperatures from 590 to 1567 K at pressures of approximately 1, 10, 20, and 30 atm. These data represent the most comprehensive set of experiments currently available for isobutane oxidation and further accentuate the complementary attributes of the two techniques toward high-pressure oxidation experiments over a wide range of temperatures. The experimental results were used to validate a detailed chemical kinetic model composed of 1328 reactions involving 230 species. This mechanism has been successfully used to simulate previously published ignition delay times as well. A thorough sensitivity analysis was performed to gain further insight to the chemical processes occurring at various conditions. Additionally, useful ignition delay time correlations were developed for temperatures greater than 1025 K. Comparisons are also made with available isobutane data from the literature, as well as with 100% n-butane and 50-50% n-butane-isobutane mixtures in air that were presented by the authors in recent studies. In general, the kinetic model shows excellent agreement with the data over the wide range of conditions of the present study. (author)

Healy, D.; Curran, H.J. [Combustion Chemistry Centre, School of Chemistry, NUI Galway (Ireland); Donato, N.S.; Aul, C.J.; Petersen, E.L. [Department of Mechanical Engineering, Texas A and M University, College Station, TX (United States); Zinner, C.M. [Mechanical, Materials and Aerospace Engineering, University of Central Florida, Orlando, FL (United States); Bourque, G. [Rolls-Royce Canada Limited, 9500 Cote de Liesse, Lachine, Quebec (Canada)

2010-08-15T23:59:59.000Z

64

A Direct Error Measure for Affine Models of Nonlinear Algebraic Systems  

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

A Direct Error Measure for Affine Models of Nonlinear Algebraic Systems A Direct Error Measure for Affine Models of Nonlinear Algebraic Systems Speaker(s): David Lorenzetti Date: June 2, 1999 - 12:00pm Location: Bldg. 90 The Newton-Raphson solution of a nonlinear system iterately linearizes the equations, then steps to the solution of the resulting affine model. When a step exceeds the predictive range of its model, the method can diverge. The traditional response -- aggregating the equations into a cost function, and applying a minimization method -- suppresses information about how each equation model performs. Direct error measures examine the equations individually, allowing finer control over step lengths. The seminar will develop one such measure through the geometry of simple one- and two-dimensional examples, then present results from a suite of larger

65

Comparison of Model Estimated and Measured Direct-Normal Solar Irradiance  

E-Print Network (OSTI)

Direct-normal solar irradiance (DNSI), the total energy in the solar spectrum incident in unit time on a unit area at the earth's surface perpendicular to the direction to the Sun, depends only on atmospheric extinction of solar energy without regard to the details of the extinction - whether absorption or scattering. Here we report a set of closure experiments performed in north-central Oklahoma in April 1996, under cloud-free conditions, wherein measured atmospheric composition and aerosol optical thickness are input to a radiative transfer model, MODTRAN-3, to estimate DNSI, which is then compared with measured values obtained with normal incidence pyrheliometers and absolute cavity radiometers. Uncertainty in aerosol optical thickness (AOT) dominates the uncertainty in DNSI calculation. AOT measured by an independently calibrated sunphotometer and a rotating Direct-Normal Solar Irradiance - A Closure Experiment, Halthore et al. 2 shadow-band radiometer agree to within the uncerta...

Rangasayi Halthore; Schwartz; S. E.; Michalsky; J. J.; Anderson; G. P.; Gail P. Anderson; Ferrare R. A.; ten Brink H. M; Holben B. N.; Harry M. Ten Brink

1997-01-01T23:59:59.000Z

66

Direct measurement of the $^{44}$Ti($\\alpha$,p) reaction of importance to supernovae, using reclaimed $^{44}$Ti  

E-Print Network (OSTI)

Direct measurement of the $^{44}$Ti($\\alpha$,p) reaction of importance to supernovae, using reclaimed $^{44}$Ti

CERN. Geneva; Lindroos, Mats; CERN. Geneva. ISOLDE and Neutron Time-of-Flight Experiments Committee; INTC

2007-01-01T23:59:59.000Z

67

Method for controlling directional drilling in response to horns detected by electromagnetic energy propagation resistivity measurements  

Science Conference Proceedings (OSTI)

For use in conjunction with an earth borehole drilling apparatus that includes: a drilling rig; a drill string operating from said drilling rig for drilling an earth borehole, said drill string including a bottom hole arrangement comprising a drill bit, a downhole resistivity measuring subsystem for measuring downhole formation resistivity near said bit by propagating electromagnetic energy into earth formations near said bit, receiving electromagnetic energy that has propagated through the formations and producing measurement signals that depend on the received signals; a method is described for directing the drilling of a well bore with respect to a geological bed boundary in said earth formations, comprising the steps of: producing from said measurement signals a recording of downhole formation resistivity as a function of borehole depth, determining the presence of a horn in said resistivity recording; and implementing a change in the drilling direction of said drill bit in response to said determination of the presence of a horn.

Luling, M.

1993-08-31T23:59:59.000Z

68

Steady decline of east Asian monsoon winds, 19692000: Evidence from direct ground measurements of wind speed  

E-Print Network (OSTI)

Steady decline of east Asian monsoon winds, 1969­2000: Evidence from direct ground measurements winter monsoon but strengthen the summer monsoon, because of stronger warming over high-latitude land with the east Asian monsoon has significantly weakened in both winter and summer in the recent three decades

Chang, Chih-Pei

69

DIRECT MEASUREMENT OF WATER AND SOLUTE FLUXES USING A PASSIVE SURFACE WATER FLUX METER  

E-Print Network (OSTI)

DIRECT MEASUREMENT OF WATER AND SOLUTE FLUXES USING A PASSIVE SURFACE WATER FLUX METER J Surface Water Flux Meter (PSFM). Current techniques for estimating contaminant mass inputs to impaired flux meter, MS Thesis, UF. This work was supported by the United States Department of Agriculture

Watson, Craig A.

70

IN-LINE MEASUREMENTS BY COLORIMETRY. PART I. MEASUREMENTS OF ABSORPTION SPECTRA FOR THE DIRECT COLORIMETRIC DETERMINATION OF URANIUM.  

SciTech Connect

The absorption spectra of uranium (VI) and uranium (IV) in aqueous nitric acid solutions and in 30% TBP/Shellsol-T solutions were established. The absorbance of the various solutions was measured as a function of the wavelength, uranium concentration and nitric acid concentration. Most of the results obtained are presented in the form of diagrams. On the basis of the present investigation the possibility of using a direct in-line colorimetric determination of uranium in plant solutions can be assessed at each individual measuring point. (auth)

Markl, P.; Humblet, L.; Wichmann, H.; Eschrich, H.

1966-04-15T23:59:59.000Z

71

Improvement of Tornado Warnings by Doppler Radar Measurement of Mesocyclone Rotational Kinetic Energy  

Science Conference Proceedings (OSTI)

A significant improvement in the reliability and timeliness of tornado warnings can be achieved through quantitative measurement by Doppler radar of selected mesocyclone features. The mesocyclone, a midsize circulation found in some of the most ...

Ralph J. Donaldson Jr.; Paul R. Desrochers

1990-06-01T23:59:59.000Z

72

Verification of BLAST by comparison with direct gain test cell measurements  

DOE Green Energy (OSTI)

Comparisons between temperatures measured in a direct solar gain test cell and temperatures predicted by the building energy analysis computer program BLAST are reported. The comparisons were performed for three distinct climate periods; the simulations were driven by weather data collected at the test cell site in Los Alamos, New Mexico. The test cell configurations and weather data manipulations are described; quantitative evaluations of the comparisons between measured and predicted interior temperatures are presented; limitations of the comparisons are discussed; and sensitivities of the simulation results to uncertainties in the measured parameters are examined.

Andersson, B.; Bauman, F.; Kammerud, R.

1980-11-01T23:59:59.000Z

73

An Improved Multipyranometer Array for the Measurement of Direct and Diffuse Solar Radiation  

E-Print Network (OSTI)

This paper describes an improved multipyranometer array (MPA) for the continuous remote measurement of direct and diffuse solar radiation. The MPA described in this paper is an improvement over previously published MPA studies due to the incorporation of an artificial horizon that prevents reflected ground radiation from striking the tilted sensors. In this paper a description of the NIST-traceable calibration facility is provided and preliminary results are presented that compare the MPA predicted beam to beam measurements from a precision normal incidence pyrheliometer and diffuse measurements from a precision shadow-band pyranometer respectively.

Munger, B.; Haberl, J. S.

1994-01-01T23:59:59.000Z

74

Fundamental Kinetics Database Utilizing Shock Tube Measurements (Volume 1 and Volume 2)  

DOE Data Explorer (OSTI)

The data from shock tube experiments generally takes three forms: ignition delay times, species concentration time-histories and reaction rate measurements. Volume 1 focuses on ignition delay time data measured and published by the Shock Tube Group in the Mechanical Engineering Department of Stanford University. The cut-off date for inclusion into this volume was January 2005. Volume 2 focuses on species concentration time-histories and was cut off December 2005. The two volumes are in PDF format and are accompanied by a zipped file of supporting data.

Davidson, D.F.; Hanson, R.K

75

The direct measurement of ablation pressure driven by 351-nm laser radiation  

Science Conference Proceedings (OSTI)

The instantaneous scaling of ablation pressure to laser intensity is directly inferred for ramp compression of diamond targets irradiated by 351-nm light. Continuously increasing pressure profiles from 100 to 970 GPa are produced by direct-drive laser ablation at intensities up to 7 x 10{sup 13} W/cm{sup 2}. The free-surface velocity on the rear of the target is used to directly infer the instantaneous ablation-pressure profile at the front of the target. The laser intensity on target is determined by laser power measurements and fully characterized laser spots. The ablation pressure is found to depend on the laser intensity as P(GPa)=42({+-}3)[I(TW/cm{sup 2})]{sup 0.71({+-}0.01)}.

Fratanduono, D. E. [Laboratory for Laser Energetics, University of Rochester, 250 East River Road, Rochester, New York 14623-1299 (United States); Department of Mechanical Engineering, University of Rochester, 250 East River Road, Rochester, New York 14623-1299 (United States); Lawrence Livermore National Laboratory, Livermore, California 94550 (United States); Boehly, T. R. [Laboratory for Laser Energetics, University of Rochester, 250 East River Road, Rochester, New York 14623-1299 (United States); Celliers, P. M.; Eggert, J. H.; Smith, R. F.; Hicks, D. G.; Collins, G. W. [Lawrence Livermore National Laboratory, Livermore, California 94550 (United States); Barrios, M. A. [Laboratory for Laser Energetics, University of Rochester, 250 East River Road, Rochester, New York 14623-1299 (United States); Department of Physics and Astronomy, University of Rochester, 250 East River Road, Rochester, New York 14623-1299 (United States); Meyerhofer, D. D. [Laboratory for Laser Energetics, University of Rochester, 250 East River Road, Rochester, New York 14623-1299 (United States); Department of Mechanical Engineering, University of Rochester, 250 East River Road, Rochester, New York 14623-1299 (United States); Department of Physics and Astronomy, University of Rochester, 250 East River Road, Rochester, New York 14623-1299 (United States)

2011-10-01T23:59:59.000Z

76

Scanning transmission electron microscopy strain measurement from millisecond frames of a direct electron charge coupled device  

Science Conference Proceedings (OSTI)

A high-speed direct electron detection system is introduced to the field of transmission electron microscopy and applied to strain measurements in semiconductor nanostructures. In particular, a focused electron probe with a diameter of 0.5 nm was scanned over a fourfold quantum layer stack with alternating compressive and tensile strain and diffracted discs have been recorded on a scintillator-free direct electron detector with a frame time of 1 ms. We show that the applied algorithms can accurately detect Bragg beam positions despite a significant point spread each 300 kV electron causes during detection on the scintillator-free camera. For millisecond exposures, we find that strain can be measured with a precision of 1.3 Multiplication-Sign 10{sup -3}, enabling, e.g., strain mapping in a 100 Multiplication-Sign 100 nm{sup 2} region with 0.5 nm resolution in 40 s.

Mueller, Knut; Rosenauer, Andreas [Institut fuer Festkoerperphysik, Universitaet Bremen, Otto-Hahn-Allee 1, 28359 Bremen (Germany); Ryll, Henning; Ordavo, Ivan; Ihle, Sebastian; Soltau, Heike [PNSensor GmbH, Roemerstrasse 28, 80803 Muenchen (Germany); Strueder, Lothar [Max-Planck-Institut Halbleiterlabor, Otto-Hahn-Ring 6, 81739 Muenchen (Germany); Volz, Kerstin [Materials Science Center and Faculty of Physics, Philipps Universitaet Marburg, Hans-Meerwein-Strasse, 35032 Marburg (Germany); Zweck, Josef [Institut fuer Experimentelle und Angewandte Physik, Universitaet Regensburg, Universitaetsstrasse 31, 93040 Regensburg (Germany)

2012-11-19T23:59:59.000Z

77

First Direct Measurement of the {sup 17}F(p,{gamma}){sup 18}Ne Cross Section  

SciTech Connect

The rate of the {sup 17}F(p,{gamma}){sup 18}Ne reaction is important in various astrophysical events. A previous {sup 17}F(p,p){sup 17}F measurement identified a 3{sup +} state providing the strongest resonance contribution, but the resonance strength was unknown. We have directly measured the {sup 17}F(p,{gamma}){sup 18}Ne reaction using a mixed beam of {sup 17}F and {sup 17}O at ORNL. The resonance strength for the 3{sup +} resonance in {sup 18}Ne was found to be {omega}{gamma}=33{+-}14(stat){+-}17(syst) meV, corresponding to a {gamma} width of {gamma}{sub {gamma}}=56{+-}24(stat){+-}30(syst) meV. An upper limit on the direct capture of S(E){<=}65 keV b was determined at an energy of 800 keV.

Chipps, K. A.; Greife, U. [Colorado School of Mines, Golden, Colorado 80401 (United States); Bardayan, D. W.; Smith, M. S. [Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831 (United States); Blackmon, J. C. [Louisiana State University, Baton Rouge, Louisiana 70803 (United States); Chae, K. Y.; Moazen, B. H.; Pittman, S. T. [University of Tennessee, Knoxville, Tennessee 37996 (United States); Hatarik, R.; Peters, W. A. [Rutgers University, New Brunswick, New Jersey 08901 (United States); Kozub, R. L.; Shriner, J. F. Jr. [Tennessee Technological University, Cookeville, Tennessee 38505 (United States); Matei, C. [Oak Ridge Associated Universities, Oak Ridge, Tennessee 37830 (United States); Nesaraja, C. D.; Pain, S. D. [Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831 (United States); University of Tennessee, Knoxville, Tennessee 37996 (United States)

2009-04-17T23:59:59.000Z

78

Measuring of fissile isotopes partial antineutrino spectra in direct experiment at nuclear reactor  

E-Print Network (OSTI)

The direct measuring method is considered to get nuclear reactor antineutrino spectrum. We suppose to isolate partial spectra of the fissile isotopes by using the method of antineutrino spectrum extraction from the inverse beta decay positron spectrum applied at Rovno experiment. This admits to increase the accuracy of partial antineutrino spectra forming the total nuclear reactor spectrum. It is important for the analysis of the reactor core fuel composition and could be applied for non-proliferation purposes.

V. V. Sinev

2009-02-22T23:59:59.000Z

79

Measuring of fissile isotopes partial antineutrino spectra in direct experiment at nuclear reactor  

E-Print Network (OSTI)

The direct measuring method is considered to get nuclear reactor antineutrino spectrum. We suppose to isolate partial spectra of the fissile isotopes by using the method of antineutrino spectrum extraction from the inverse beta decay positron spectrum applied at Rovno experiment. This admits to increase the accuracy of partial antineutrino spectra forming the total nuclear reactor spectrum. It is important for the analysis of the reactor core fuel composition and could be applied for non-proliferation purposes.

Sinev, V V

2009-01-01T23:59:59.000Z

80

Direct measurement of the 14N(p,g)15O S-factor  

E-Print Network (OSTI)

We have measured the 14N(p,g)15O excitation function for energies in the range E_p = 155--524 keV. Fits of these data using R-matrix theory yield a value for the S-factor at zero energy of 1.64(17) keV b, which is significantly smaller than the result of a previous direct measurement. The corresponding reduction in the stellar reaction rate for 14N(p,g)15O has a number of interesting consequences, including an impact on estimates for the age of the Galaxy derived from globular clusters.

R. C. Runkle; A. E. Champagne; C. Angulo; C. Fox; C. Iliadis; R. Longland; J. Pollanen

2004-08-17T23:59:59.000Z

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81

Direct measurement of the quantum state of the electromagnetic field in a superconducting transmission line  

E-Print Network (OSTI)

We propose an experimental procedure to directly measure the state of an electromagnetic field inside a resonator, corresponding to a superconducting transmission line, coupled to a Cooper-pair box (CPB). The measurement protocol is based on the use of a dispersive interaction between the field and the CPB, and the coupling to an external classical field that is tuned to resonance with either the field or the CPB. We present a numerical simulation that demonstrates the feasibility of this protocol, which is within reach of present technology.

F. de Melo; L. Aolita; F. Toscano; L. Davidovich

2006-02-23T23:59:59.000Z

82

Nuclear matrix elements from direct lifetime or cross-section measurements  

SciTech Connect

The method of simultaneous lifetime and g factor measurements using a plunger device and the RDDS and TDRIV techniques is introduced. Results on lifetimes and hyperfine-interaction parameters for 2{sup +}{sub 1} states in {sup 104-108}Pd, {sup 96,98,104}Ru, and {sup 92,94}Zr, using a plunger device. Another method to obtain electromagnetic matrix elements is direct cross section measurements using NRF. The method is outlined, and some recent results on {sup 76}Se are shown.

Werner, V.; Cooper, N.; Hinton, M.; Ilie, G.; Radeck, D. [Wright Nuclear Structure Laboratory, Yale University, P.O. Box 208120, New Haven, CT 06520-8120 (United States); Wright Nuclear Structure Laboratory, Yale University, P.O. Box 208120, New Haven, CT 06520-8120 (United States) and Department of Physics, University of Surrey, Guilford, GU27XH (United Kingdom); Wright Nuclear Structure Laboratory, Yale University, P.O. Box 208120, New Haven, CT 06520-8120 (United States) and National Institute for Physics and Nuclear Engineering, P.O. Box MG-6, Bucharest-Magurele (Romania); Wright Nuclear Structure Laboratory, Yale University, P.O. Box 208120, New Haven, CT 06520-8120 (United States) and Institut fuer Kernphysik, Universitaet zu Koeln, Zuelpicher Str. 77, 50937 Koeln (Germany)

2012-11-20T23:59:59.000Z

83

GUINEVERE experiment: Kinetic analysis of some reactivity measurement methods by deterministic and Monte Carlo codes  

Science Conference Proceedings (OSTI)

The GUINEVERE experiment (Generation of Uninterrupted Intense Neutrons at the lead Venus Reactor) is an experimental program in support of the ADS technology presently carried out at SCK-CEN in Mol (Belgium). In the experiment a modified lay-out of the original thermal VENUS critical facility is coupled to an accelerator, built by the French body CNRS in Grenoble, working in both continuous and pulsed mode and delivering 14 MeV neutrons by bombardment of deuterons on a tritium-target. The modified lay-out of the facility consists of a fast subcritical core made of 30% U-235 enriched metallic Uranium in a lead matrix. Several off-line and on-line reactivity measurement techniques will be investigated during the experimental campaign. This report is focused on the simulation by deterministic (ERANOS French code) and Monte Carlo (MCNPX US code) calculations of three reactivity measurement techniques, Slope ({alpha}-fitting), Area-ratio and Source-jerk, applied to a GUINEVERE subcritical configuration (namely SC1). The inferred reactivity, in dollar units, by the Area-ratio method shows an overall agreement between the two deterministic and Monte Carlo computational approaches, whereas the MCNPX Source-jerk results are affected by large uncertainties and allow only partial conclusions about the comparison. Finally, no particular spatial dependence of the results is observed in the case of the GUINEVERE SC1 subcritical configuration. (authors)

Bianchini, G.; Burgio, N.; Carta, M. [ENEA C.R. CASACCIA, via Anguillarese, 301, 00123 S. Maria di Galeria Roma (Italy); Peluso, V. [ENEA C.R. BOLOGNA, Via Martiri di Monte Sole, 4, 40129 Bologna (Italy); Fabrizio, V.; Ricci, L. [Univ. of Rome La Sapienza, C/o ENEA C.R. CASACCIA, via Anguillarese, 301, 00123 S. Maria di Galeria Roma (Italy)

2012-07-01T23:59:59.000Z

84

PROSPECTS FOR MEASURING THE RELATIVE VELOCITIES OF GALAXY CLUSTERS IN PHOTOMETRIC SURVEYS USING THE KINETIC SUNYAEV-ZEL'DOVICH EFFECT  

SciTech Connect

We consider the prospects for measuring the pairwise kinetic Sunyaev-Zel'dovich (kSZ) signal from galaxy clusters discovered in large photometric surveys such as the Dark Energy Survey (DES). We project that the DES cluster sample will, in conjunction with existing mm-wave data from the South Pole Telescope (SPT), yield a detection of the pairwise kSZ signal at the 8{sigma}-13{sigma} level, with sensitivity peaking for clusters separated by {approx}100 Mpc distances. A next-generation version of SPT would allow for a 18{sigma}-30{sigma} detection and would be limited by variance from the kSZ signal itself and the residual thermal Sunyaev-Zel'dovich (tSZ) signal. Throughout our analysis, we assume photometric redshift errors that wash out the signal for clusters separated by {approx}<50 Mpc; a spectroscopic survey of the DES sample would recover this signal and allow for a 26{sigma}-43{sigma} detection, and would again be limited by kSZ/tSZ variance. Assuming a standard model of structure formation, these high-precision measurements of the pairwise kSZ signal will yield detailed information on the gas content of the galaxy clusters. Alternatively, if the gas can be sufficiently characterized by other means (e.g., using tSZ, X-ray, or weak lensing), then the relative velocities of the galaxy clusters can be isolated, thereby providing a precision measurement of gravity on 100 Mpc scales. We briefly consider the utility of these measurements for constraining theories of modified gravity.

Keisler, Ryan [Kavli Institute for Cosmological Physics, University of Chicago, 5640 South Ellis Avenue, Chicago, IL 60637 (United States); Schmidt, Fabian, E-mail: rkeisler@uchicago.edu, E-mail: fabians@astro.princeton.edu [Department of Astrophysical Sciences, Princeton University, Princeton, NJ 08540 (United States)

2013-03-10T23:59:59.000Z

85

Two-particle Direct Photon-Jet Correlation Measurements in PHENIX  

E-Print Network (OSTI)

Various 2-particle direct photon-hadron correlation strengths and yields in $p+p$ and $Au+Au$ collisions at sqrtsNN= 200 GeV are presented. The per-trigger yield of direct photon hadron pairs from direct-photon-jet correlations in is obtained by a statistical subtraction of the decay photon pairs from inclusive photon-hadron sample. The decay photon per-trigger yields are estimated from the measured $\\pi^0$-hadron by means of a Monte Carlo based calculation which takes into account decay kinematics and detector response. Under the assumption that the suppression is nearly pt independent using a specific averaging scheme, we find an average ratio of Au+Au to p+p per-trigger photon yields, $I_{AA}$, consistent with the single particle suppression level Raa, which can be interpreted as a qualitative confirmation of the basic geometrical picture of jet suppression at RHIC. The application of the event by event photon isolation cuts in $p+p$ results our highest precision measurement yet, and allows for precision studies of the baseline fragmentation function $D(z)$, and well as a variable \\pout which is proportional to the apparent intrinsic $k_T$, or non-zero transverse momentum of the original collision partons. With a model dependent extraction method, the average $sqrt()$ at this center of mass energy in p+p is found to be in the vicinity of 3 GeV, consistent with analysis of di-hadron (di-jet) correlations. This and the improved precision in the isolated yields warrant further comparison with the baseline perturbative QCD (pQCD) calculations used in the various models of jet energy loss. Finally, we present a unique direct measurement of single prompt photons from jet fragmentation.

Justin Frantz

2009-01-10T23:59:59.000Z

86

Prediction and measurement of direct-normal solar irradiance: A closure experiment  

Science Conference Proceedings (OSTI)

Direct-normal solar irradiance (DNSI), the total energy in the solar spectrum incident on a plane perpendicular to the Sun`s direction on a unit area at the earth`s surface in unit time, depends only on the atmospheric extinction of sunlight without regard to the details of extinction--whether absorption or scattering. Here the authors describe a set of closure experiments performed in north-central Oklahoma, wherein measured atmospheric composition is input to a radiative transfer model, MODTRAN-3, to predict DNSI, which is then compared to measured values. Thirty six independent comparisons are presented; the agreement between predicted and measured values falls within the combined uncertainties in the prediction (2%) and measurement (0.2%) albeit with a slight bias ({approximately} 1% overprediction) that is independent of the solar zenith angle. Thus these results establish the adequacy of current knowledge of the solar spectrum and atmospheric extinction as embodied in MODTRAN-3 for use in climate models. An important consequence is the overwhelming likelihood that the atmospheric clear-sky absorption is accurately described to within comparable uncertainties.

Halthore, R.N.; Schwartz, S.E. [Brookhaven National Lab., Upton, NY (United States); Michalsky, J.J. [State Univ. of New York, Albany, NY (United States); Anderson, G.P. [Hanscomb AFB (United States); Ferrare, R.A. [National Aeronautics and Space Administration, Greenbelt, MD (United States). Goddard Space Flight Center; Ten Brink, H.M. [Energy Research Inst. (Netherlands)

1997-03-01T23:59:59.000Z

87

Measurement of the Rates of Production and Dissipation of Turbulent Kinetic Energy in an Energetic Tidal Flow: Red Wharf Bay Revisited  

Science Conference Proceedings (OSTI)

Simultaneous measurements of the rates of turbulent kinetic energy (TKE) dissipation (?) and production (P) have been made over a period of 24 h at a tidally energetic site in the northern Irish Sea in water of 25-m depth. Some ? profiles from 5 ...

Tom P. Rippeth; John H. Simpson; Eirwen Williams; Mark E. Inall

2003-09-01T23:59:59.000Z

88

Direct thrust measurements and modelling of a radio-frequency expanding plasma thruster  

SciTech Connect

It is shown analytically that the thrust from a simple plasma thruster (in the absence of a magnetic field) is given by the maximum upstream electron pressure, even if the plasma diverges downstream. Direct thrust measurements of a thruster are then performed using a pendulum thrust balance and a laser displacement sensor. A maximum thrust of about 2 mN is obtained at 700 W for a thruster length of 17.5 cm and a flow rate of 0.9 mg s{sup -1}, while a larger thrust of 4 mN is obtained at a similar power for a length of 9.5 cm and a flow rate of 1.65 mg s{sup -1}. The measured thrusts are in good agreement with the maximum upstream electron pressure found from measurements of the plasma parameters and in fair agreement with a simple global approach used to model the thruster.

Lafleur, T.; Charles, C.; Boswell, R. W. [Space Plasma, Power and Propulsion Group, Research School of Physics and Engineering, The Australian National University, Canberra ACT 0200 (Australia); Takahashi, K. [Space Plasma, Power and Propulsion Group, Research School of Physics and Engineering, The Australian National University, Canberra ACT 0200 (Australia); Department of Electrical Engineering and Computer Science, Iwate University, Morioka 020-8551 (Japan)

2011-08-15T23:59:59.000Z

89

Comparison of model estimated and measured direct-normal solar irradiance  

SciTech Connect

Direct-normal solar irradiance (DNSI), the energy in the solar spectrum incident in unit time at the Earth{close_quote}s surface on a unit area perpendicular to the direction to the Sun, depends only on atmospheric extinction of solar energy without regard to the details of the extinction, whether absorption or scattering. Here we report a set of closure experiments performed in north central Oklahoma in April 1996 under cloud-free conditions, wherein measured atmospheric composition and aerosol optical thickness are input to a radiative transfer model, MODTRAN 3, to estimate DNSI, which is then compared with measured values obtained with normal incidence pyrheliometers and absolute cavity radiometers. Uncertainty in aerosol optical thickness (AOT) dominates the uncertainty in DNSI calculation. AOT measured by an independently calibrated Sun photometer and a rotating shadow-band radiometer agree to within the uncertainties of each measurement. For 36 independent comparisons the agreement between measured and model-estimated values of DNSI falls within the combined uncertainties in the measurement (0.3{endash}0.7{percent}) and model calculation (1.8{percent}), albeit with a slight average model underestimate ({minus}0.18{plus_minus}0.94){percent}; for a DNSI of 839Wm{sup {minus}2} this corresponds to {minus}1.5{plus_minus}7.9Wm{sup {minus}2}. The agreement is nearly independent of air mass and water-vapor path abundance. These results thus establish the accuracy of the current knowledge of the solar spectrum, its integrated power, and the atmospheric extinction as a function of wavelength as represented in MODTRAN 3. An important consequence is that atmospheric absorption of short-wave energy is accurately parametrized in the model to within the above uncertainties. {copyright} 1997 American Geophysical Union

Halthore, R.N.; Schwartz, S.E. [Department of Applied Science, Brookhaven National Laboratory, Upton, New York (United States)] [Department of Applied Science, Brookhaven National Laboratory, Upton, New York (United States); Michalsky, J.J. [Atmospheric Sciences Research Center, State University of New York at Albany (United States)] [Atmospheric Sciences Research Center, State University of New York at Albany (United States); Anderson, G.P. [Phillips Laboratory/Geophysics Directorate, Hanscom Air Force Base, Massachusetts (United States)] [Phillips Laboratory/Geophysics Directorate, Hanscom Air Force Base, Massachusetts (United States); Ferrare, R.A. [Hughes STX Corporation, Lanham, Maryland (United States)] [Hughes STX Corporation, Lanham, Maryland (United States); Holben, B.N. [NASA Goddard Space Flight Center, Greenbelt, Maryland (United States)] [NASA Goddard Space Flight Center, Greenbelt, Maryland (United States); Ten Brink, H.M. [Netherlands Energy Research Foundation, ECN, Petten (Netherlands)] [Netherlands Energy Research Foundation, ECN, Petten (Netherlands)

1997-12-01T23:59:59.000Z

90

Measurements of the Directional Spectra of Shallow Water Waves Using the Maximum Entropy Principle and a Single Ocean Bottom Seismometer  

Science Conference Proceedings (OSTI)

A new method for measurement of the directional spectra of surface gravity (water) waves is presented here. Measurements are made at a single point by orthogonally mounted seismometers buried 0.5 meters below the seabed surface and a pressure ...

Tom Nye; Tokuo Yamamoto; Mark Trevorrow

1990-10-01T23:59:59.000Z

91

Microreactor for fast chemical kinetics  

E-Print Network (OSTI)

The chemical reaction process in a T-shaped microchannel is studied experimentally through the reaction of Ca++ with a fluorescent tracer, Calcium-green. For thin channels (10 um), diffusion of species is found to behave in a way independent of the thickness direction. In such a situation, simulations of a two-dimensional reaction-diffusion model agree remarkably well with the experimental measurements. The comparison of experiments and simulations is used to measure the chemical kinetic constant, which we find to be k=3.2 x 10^5 dm^3/(mol s). Applications of the analysis to faster reactions and to micro-titration are also discussed.

Baroud, C N; Menetrier, L; Tabeling, P; Baroud, Charles N.; Okkels, Fridolin; Menetrier, Laure; Tabeling, Patrick

2003-01-01T23:59:59.000Z

92

An improved multipyranometer array for the measurement of direct and diffuse solar radiation  

E-Print Network (OSTI)

This thesis describes the development of an improved multipyranometer array (NDA) for the continuous remote measurement of direct and diff-use solar radiation. The NWA described in this thesis is an improvement over previously published MPA studies due to the incorporation of an artificial horizon that prevents reflected ground radiation from striking the tilted sensors, the development of an improved solution scheme for the calculation of the beam and diff-use solar radiation components, and the development of an empirical spectral correction for the photovoltaic-type sensors used in the NWA. In this thesis a description of the NIST-traceable calibration facility is provided and results are presented that compare the NWA predicted beam to beam measurements from a precision normal incidence pyrheliometer.

Munger, Bryce Kirtley

1997-01-01T23:59:59.000Z

93

An Improved Multipyranometer Array for the Measurement of Direct and Diffuse Solar Radiation  

E-Print Network (OSTI)

This thesis describes the development of an improved multipyranometer array (MPA) for the continuous remote measurement of direct and diffuse solar radiation. The MPA described in this thesis is an improvement over previously published MPA studies due to the incorporation of an artificial horizon that prevents reflected ground radiation from striking the tilted sensors, the development of an improved solution scheme for the calculation of the beam and diffuse solar radiation components, and the development of an empirical spectral correction for the photovoltaic-type sensors used in the MPA. In this thesis a description of the NIST-traceable calibration facility is provided and results are presented that compare the MPA predicted beam to beam measurements from a precision normal incidence pyrheliometer.

Munger, Bryce Kirtley

1997-12-01T23:59:59.000Z

94

Lateral Spectrum Splitting Concentrator Photovoltaics: Direct Measurement of Component and Submodule Efficiency  

Science Conference Proceedings (OSTI)

To achieve high energy conversion efficiency, a solar module architecture called lateral spectrum splitting concentrator photovoltaics (LSSCPV) is being developed. LSSCPV can concentrate available sunlight and laterally split a single beam into bands with different spectra for absorption by different solar cells with band gaps matched to the split spectrum. Test assemblies of a sample LSSCPV architecture were constructed, each of which contains four p-n junctions and two optical pieces. Independent experiments or simulations had been implemented on the components but by using optimal assumptions. In order to examine the actual performances of all the components, which are dependent on each other and the light source, direct outdoor measurements were made. A set of self-consistent efficiency definitions was articulated and a test bed was developed to measure the parameters required by the efficiency calculation. By comparing the component efficiency items derived from the outdoor measurement and the expected values based on independent simulations, the potential opportunities for efficiency improvement are determined. In the outdoor measurement at the University of Delaware, the optical component demonstrated 89.1% efficiency. Additional assemblies were tested at the National Renewable Energy Laboratory. One assembly demonstrated 36.7% submodule efficiency, which compares favorably with the 32.6% previously reported verified submodule efficiency.

Xiaoting, W.; Waite, N.; Murcia, P.; Emery, K.; Steiner, M.; Kiamilev, F.; Goossen, K.; Honsberg, C.; Barnett, A.

2012-03-01T23:59:59.000Z

95

Direct measurement of the {ital D}{sub {ital s}} branching fraction to {phi}{pi}  

Science Conference Proceedings (OSTI)

The Beijing Spectrometer (BES) Collaboration has observed exclusive pair production of {ital D}{sub {ital s}} mesons at the Beijing Electron-Positron Collider (BEPC) at a center-of-mass energy of 4.03 GeV. The {ital D}{sub {ital s}} mesons are detected in the {phi}{pi}{sup +}, {ital {bar K}} {sup *0}{ital K}{sup +}, and {ital {bar K}} {sup 0}{ital K}{sup +} decay modes; two fully reconstructed events yield the value (3.9{sub {minus}1.9{minus}1.1}{sup +5.1+1.8})% for the {ital D}{sub {ital s}} branching fraction to {phi}{pi}. This is the first direct, model-independent measurement of this quantity.

Bai, J.Z.; Bardon, O.; Blum, I.; Breakstone, A.; Burnett, T.; Chen, G.P.; Chen, H.F.; Chen, J.; Chen, S.J.; Chen, S.M.; Chen, Y.; Chen, Y.B.; Chen, Y.Q.; Cheng, B.S.; Cowan, R.F.; Cui, H.C.; Cui, X.Z.; Ding, H.L.; Du, Z.Z.; Dunwoodie, W.; Fan, X.L.; Fang, J.; Fero, M.; Gao, C.S.; Gao, M.L.; Gao, S.Q.; Gao, W.X.; Gratton, P.; Gu, J.H.; Gu, S.D.; Gu, W.X.; Gu, Y.F.; Guo, Y.N.; Han, S.W.; Han, Y.; Harris, F.A.; Hatanaka, M.; He, J.; He, K.R.; He, M.; Hitlin, D.G.; Hu, G.Y.; Hu, H.B.; Hu, T.; Hu, X.Q.; Huang, D.Q.; Huang, Y.Z.; Izen, J.M.; Jia, Q.P.; Jiang, C.H.; Jin, Y.; Jones, L.; Kang, S.H.; Kelsey, M.H.; Kim, B.K.; Lai, Y.F.; Lan, H.B.; Lang, P.F.; Lankford, A.; Li, F.; Li, J.; Li, P.Q.; Li, Q.; Li, R.B.; Li, W.; Li, W.D.; Li, W.G.; Li, X.; Li, X.N.; Lin, S.Z.; Liu, H.M.; Liu, J.H.; Liu, Q.; Liu, R.G.; Liu, Y.; Liu, Z.A.; Lou, X.C.; Lowery, B.; Lu, J.G.; Ma, A.M.; Ma, E.C.; Ma, J.M.; Mao, H.S.; Mao, Z.P.; Malchow, R.; Mandelkern, M.; Meng, X.C.; Ni, H.L.; Nie, J.; Olsen, S.L.; Oyang, J.; Paluselli, D.; Pan, L.J.; Panetta, J.; Porter, F.; Prabhakar, E.; Qi, N.D.; Que, Y.K.; Quigley, J.; Rong, G.; Schernau, M.; Schmid, B.; Schultz, J.; Shao, Y.Y.; Shen, D.L.; Shen, H.; Shen, X.Y.; Sheng, H.Y.; Shi, H.Z.; Shi, X.R.; Smith, A.; Soderstrom, E.; Song, X.F.; Standifird, J.; Stoker, D.; Sun, F.; Sun, H.S.; Sun, S.J.; Synodinos, J.; Tan, Y.P.; Tang, S.Q.; Toki, W.; Tong, G.L.; Torrence, E.; Wang, F.; Wang, L.S.; Wang, L.Z.; Wang, M.; Wang, P.; Wang, P.L.; Wang, S.M.; Wang, T.J.; Wang, W.; Wang, Y.Y.; Whittaker, S.; Wilson, R.; Wisniewski, W.J.; Xi, D.M.; Xia, X.M.; Xie, P.P.; Xu, D.Z.; Xu, R.S.; Xu, Z.Q.; Xue, S.T.; Yamamoto, R.; Yan, J.; Yan, W.G.; Yang, C.M.; Yang, C.Y.; Yang, W.; Yao, H.B.; Ye, M.H.; Ye, S.Z.; Yu, C.S.; Yu, C.X.; Yu, Z.Q.; Yuan, C.Z.; Zhang, B.Y.; Zhang, C.C.; Zhang, D.H.; Zhang, H.L.; Zhang, J.; Zhang, J.W.; Zhang, L.S.; Zhang, S.Q.; Zhang, Y.; Zhang, Y.Y.; Zhao, D.X.; Zhao, J.W.; Zhao, M.; Zhao, P.D.; Zhao, W.R.; Zhao, W.X.; Zheng, J.H.; (BES Collabo..

1995-10-01T23:59:59.000Z

96

Direct measurement of the mass difference between top and antitop quarks  

SciTech Connect

We present a direct measurement of the mass difference between top and antitop quarks ({Delta}m) in lepton+jets t{bar t} final states using the 'matrix element' method. The purity of the lepton+jets sample is enhanced for t{bar t} events by identifying at least one of the jet as originating from a b quark. The analyzed data correspond to 3.6 fb{sup -1} of p{bar p} collisions at {radical}s = 1.96 TeV acquired by D0 in Run II of the Fermilab Tevatron Collider. The combination of the e+jets and m+jets channels yields {Delta}m = 0.8 {+-} 1.8 (stat) {+-} 0.5 (syst) GeV, which is in agreement with the standard model expectation of no mass difference.

Abazov, Victor Mukhamedovich; /Dubna, JINR; Abbott, Braden Keim; /Oklahoma U.; Acharya, Bannanje Sripath; /Tata Inst.; Adams, Mark Raymond; /Illinois U., Chicago; Adams, Todd; /Florida State U.; Alexeev, Guennadi D.; /Dubna, JINR; Alkhazov, Georgiy D.; /St. Petersburg, INP; Alton, Andrew K.; /Michigan U. /Augustana Coll., Sioux Falls; Alverson, George O.; /Northeastern U.; Alves, Gilvan Augusto; /Rio de Janeiro, CBPF; Aoki, Masato; /Fermilab /Louisiana Tech. U.

2011-06-01T23:59:59.000Z

97

Anaerobic pyrite oxidation rates determined via direct volume-loss measurements: a Vertical Scanning Interferometric approach  

E-Print Network (OSTI)

determina- tion of dissolution/precipitation kinetic rates. A VSI assessment of pyrite dissolution rates et al., 2008) with applications to oxic ARD processes. Presented here are rate data for the inorganic experiments the bulk chemical changes in the solution composition (e.g. Fe2+ /Fe3+ ) were used to determine

Benning, Liane G.

98

A Direct Measurement of the Total Decay Width of the Top Quark  

E-Print Network (OSTI)

We present a measurement of the total decay width of the top quark using events with top-antitop-quark pair candidates reconstructed in the final state with one charged lepton and four or more hadronic jets. We use the full Tevatron Run II data set of $\\sqrt{s} = 1.96$ TeV proton-antiproton collisions recorded by the CDF II detector. The top-quark mass and the mass of the hadronically-decaying $W$ boson are reconstructed for each event and compared with distributions derived from simulated signal and background samples to extract the top-quark width (\\gmt) and the energy scale of the calorimeter jets with {\\it in-situ} calibration. For a top-quark mass $\\mtop = \\gevcc{172.5}$, we find $1.10<\\gmt<\\gev{4.05}$ at 68% confidence level, which is in agreement with the standard-model expectation of \\gev{1.3} and is the most precise direct measurement of the top-quark width to date.

CDF Collaboration; T. Aaltonen; S. Amerio; D. Amidei; A. Anastassov; A. Annovi; J. Antos; G. Apollinari; J. A. Appel; T. Arisawa; A. Artikov; J. Asaadi; W. Ashmanskas; B. Auerbach; A. Aurisano; F. Azfar; W. Badgett; T. Bae; A. Barbaro-Galtieri; V. E. Barnes; B. A. Barnett; P. Barria; P. Bartos; M. Bauce; F. Bedeschi; S. Behari; G. Bellettini; J. Bellinger; D. Benjamin; A. Beretvas; A. Bhatti; K. R. Bland; B. Blumenfeld; A. Bocci; A. Bodek; D. Bortoletto; J. Boudreau; A. Boveia; L. Brigliadori; C. Bromberg; E. Brucken; J. Budagov; H. S. Budd; K. Burkett; G. Busetto; P. Bussey; P. Butti; A. Buzatu; A. Calamba; S. Camarda; M. Campanelli; F. Canelli; B. Carls; D. Carlsmith; R. Carosi; S. Carrillo; B. Casal; M. Casarsa; A. Castro; P. Catastini; D. Cauz; V. Cavaliere; M. Cavalli-Sforza; A. Cerri; L. Cerrito; Y. C. Chen; M. Chertok; G. Chiarelli; G. Chlachidze; K. Cho; D. Chokheli; A. Clark; C. Clarke; M. E. Convery; J. Conway; M. Corbo; M. Cordelli; C. A. Cox; D. J. Cox; M. Cremonesi; D. Cruz; J. Cuevas; R. Culbertson; N. d'Ascenzo; M. Datta; P. de Barbaro; L. Demortier; L. Marchese; M. Deninno; F. Devoto; M. D'Errico; A. Di Canto; B. Di Ruzza; J. R. Dittmann; M. D'Onofrio; S. Donati; M. Dorigo; A. Driutti; K. Ebina; R. Edgar; A. Elagin; R. Erbacher; S. Errede; B. Esham; S. Farrington; J. P. Fernández Ramos; R. Field; G. Flanagan; R. Forrest; M. Franklin; J. C. Freeman; H. Frisch; Y. Funakoshi; C. Galloni; A. F. Garfinkel; P. Garosi; H. Gerberich; E. Gerchtein; S. Giagu; V. Giakoumopoulou; K. Gibson; C. M. Ginsburg; N. Giokaris; P. Giromini; G. Giurgiu; V. Glagolev; D. Glenzinski; M. Gold; D. Goldin; A. Golossanov; G. Gomez; G. Gomez-Ceballos; M. Goncharov; O. González López; I. Gorelov; A. T. Goshaw; K. Goulianos; E. Gramellini; S. Grinstein; C. Grosso-Pilcher; R. C. Group; J. Guimaraes da Costa; S. R. Hahn; J. Y. Han; F. Happacher; K. Hara; M. Hare; R. F. Harr; T. Harrington-Taber; K. Hatakeyama; C. Hays; J. Heinrich; M. Herndon; A. Hocker; Z. Hong; W. Hopkins; S. Hou; R. E. Hughes; U. Husemann; M. Hussein; J. Huston; G. Introzzi; M. Iori; A. Ivanov; E. James; D. Jang; B. Jayatilaka; E. J. Jeon; S. Jindariani; M. Jones; K. K. Joo; S. Y. Jun; T. R. Junk; M. Kambeitz; T. Kamon; P. E. Karchin; A. Kasmi; Y. Kato; W. Ketchum; J. Keung; B. Kilminster; D. H. Kim; H. S. Kim; J. E. Kim; M. J. Kim; S. B. Kim; S. H. Kim; Y. K. Kim; Y. J. Kim; N. Kimura; M. Kirby; K. Knoepfel; K. Kondo; D. J. Kong; J. Konigsberg; A. V. Kotwal; M. Kreps; J. Kroll; M. Kruse; T. Kuhr; M. Kurata; A. T. Laasanen; S. Lammel; M. Lancaster; K. Lannon; G. Latino; H. S. Lee; J. S. Lee; S. Leo; S. Leone; J. D. Lewis; A. Limosani; E. Lipeles; A. Lister; H. Liu; Q. Liu; T. Liu; S. Lockwitz; A. Loginov; A. Lucà; D. Lucchesi; J. Lueck; P. Lujan; P. Lukens; G. Lungu; J. Lys; R. Lysak; R. Madrak; P. Maestro; S. Malik; G. Manca; A. Manousakis-Katsikakis; F. Margaroli; P. Marino; M. Martínez; K. Matera; M. E. Mattson; A. Mazzacane; P. Mazzanti; R. McNulty; A. Mehta; P. Mehtala; C. Mesropian; T. Miao; D. Mietlicki; A. Mitra; H. Miyake; S. Moed; N. Moggi; C. S. Moon; R. Moore; M. J. Morello; A. Mukherjee; Th. Muller; P. Murat; M. Mussini; J. Nachtman; Y. Nagai; J. Naganoma; I. Nakano; A. Napier; J. Nett; C. Neu; T. Nigmanov; L. Nodulman; S. Y. Noh; O. Norniella; L. Oakes; S. H. Oh; Y. D. Oh; I. Oksuzian; T. Okusawa; R. Orava; L. Ortolan; C. Pagliarone; E. Palencia; P. Palni; V. Papadimitriou; W. Parker; G. Pauletta; M. Paulini; C. Paus; T. J. Phillips; G. Piacentino; E. Pianori; J. Pilot; K. Pitts; C. Plager; L. Pondrom; S. Poprocki; K. Potamianos; F. Prokoshin; A. Pranko; F. Ptohos; G. Punzi; N. Ranjan; I. Redondo Fernández; P. Renton; M. Rescigno; F. Rimondi; L. Ristori; A. Robson; T. Rodriguez; S. Rolli; M. Ronzani; R. Roser; J. L. Rosner; F. Ruffini; A. Ruiz; J. Russ; V. Rusu; W. K. Sakumoto; Y. Sakurai; L. Santi; K. Sato; V. Saveliev; A. Savoy-Navarro; P. Schlabach; E. E. Schmidt; T. Schwarz; L. Scodellaro; F. Scuri; S. Seidel; Y. Seiya; A. Semenov; F. Sforza; S. Z. Shalhout; T. Shears; P. F. Shepard; M. Shimojima; M. Shochet; I. Shreyber-Tecker; A. Simonenko; K. Sliwa; J. R. Smith; F. D. Snider; V. Sorin; H. Song; M. Stancari; R. St. Denis; D. Stentz; J. Strologas; Y. Sudo; A. Sukhanov; I. Suslov; K. Takemasa; Y. Takeuchi; J. Tang; M. Tecchio; P. K. Teng; J. Thom; E. Thomson; V. Thukral; D. Toback; S. Tokar; K. Tollefson; T. Tomura; D. Tonelli; S. Torre; D. Torretta; P. Totaro; M. Trovato; F. Ukegawa; S. Uozumi; F. Vázquez; G. Velev; C. Vellidis; C. Vernieri; M. Vidal; R. Vilar; J. Vizán; M. Vogel; G. Volpi; P. Wagner; R. Wallny; S. M. Wang; D. Waters; W. C. Wester III; D. Whiteson; A. B. Wicklund; S. Wilbur; H. H. Williams; J. S. Wilson; P. Wilson; B. L. Winer; P. Wittich; S. Wolbers; H. Wolfe; T. Wright; X. Wu; Z. Wu; K. Yamamoto; D. Yamato; T. Yang; U. K. Yang; Y. C. Yang; W. -M. Yao; G. P. Yeh; K. Yi; J. Yoh; K. Yorita; T. Yoshida; G. B. Yu

2013-08-19T23:59:59.000Z

99

Direct photon measurement in Au+Au collisions at $\\sqrt{s_{NN}}$=200GeV a t RHIC  

E-Print Network (OSTI)

Direct photon production in Au+Au collisions at $\\sqrt{s_{NN}}$=200 GeV has been measured. The result is compared to several theoretical calculations, and found that it is not inconsistent with ones including thermal radiation from QGP or jet-photon conversion process on top of a NLO pQCD expectation. The direct photon contribution in dilepton measurement is also evaluated.

Takao Sakaguchi

2006-01-03T23:59:59.000Z

100

Ion-Kinetic-Energy Measurements and Energy Balance in a Z-Pinch Plasma at Stagnation E. Kroupp, D. Osin, A. Starobinets, V. Fisher, V. Bernshtam, and Y. Maron  

E-Print Network (OSTI)

allowed for tracking the ion-kinetic-energy history throughout the entire K emission period of the energy balance requires information on the histories of the mass, electron temperature, and ionIon-Kinetic-Energy Measurements and Energy Balance in a Z-Pinch Plasma at Stagnation E. Kroupp, D

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101

Constraining nova observables: direct measurements of resonance strengths in 33S(p,?)34Cl  

E-Print Network (OSTI)

The 33S(p,\\gamma)34Cl reaction is important for constraining predictions of certain isotopic abundances in oxygen-neon novae. Models currently predict as much as 150 times the solar abundance of 33S in oxygen-neon nova ejecta. This overproduction factor may, however, vary by orders of magnitude due to uncertainties in the 33S(p,\\gamma)34Cl reaction rate at nova peak temperatures. Depending on this rate, 33S could potentially be used as a diagnostic tool for classifying certain types of presolar grains. Better knowledge of the 33S(p,\\gamma)34Cl rate would also aid in interpreting nova observations over the S-Ca mass region and contribute to the firm establishment of the maximum endpoint of nova nucleosynthesis. Additionally, the total S elemental abundance which is affected by this reaction has been proposed as a thermometer to study the peak temperatures of novae. Previously, the 33S(p,\\gamma)34Cl reaction rate had only been studied directly down to resonance energies of 432 keV. However, for nova peak temperatures of 0.2-0.4 GK there are 7 known states in 34Cl both below the 432 keV resonance and within the Gamow window that could play a dominant role. Direct measurements of the resonance strengths of these states were performed using the DRAGON recoil separator at TRIUMF. Additionally two new states within this energy region are reported. Several hydrodynamic simulations have been performed, using all available experimental information for the 33S(p,\\gamma)34Cl rate, to explore the impact of the remaining uncertainty in this rate on nucleosynthesis in nova explosions. These calculations give a range of ~ 20-150 for the expected 33S overproduction factor, and a range of ~ 100-450 for the 32S/33S ratio expected in ONe novae.

J. Fallis; A. Parikh; P. F. Bertone; S. Bishop; L. Buchmann; A. A. Chen; G. Christian; J. A. Clark; J. M. D'Auria; B. Davids; C. M. Deibel; B. R. Fulton; U. Greife; B. Guo; U. Hager; C. Herlitzius; D. A. Hutcheon; J. José; A. M. Laird; E. T. Li; Z. H. Li; G. Lian; W. P. Liu; L. Martin; K. Nelson; D. Ottewell; P. D. Parker; S. Reeve; A. Rojas; C. Ruiz; K. Setoodehnia; S. Sjue; C. Vockenhuber; Y. B. Wang; C. Wrede

2013-09-13T23:59:59.000Z

102

Nitrite transport in chloroplast inner envelope vesicles. I. Direct measurement of proton-linked transport  

Science Conference Proceedings (OSTI)

Chloroplast inner envelope membrane vesicles that are loaded with the pH-sensitive fluorophore, pyranine, show rapid internal acidification when nitrite is added. Acidification is dependent upon {Delta}pH, with the inside of vesicles being alkaline with respect to the outside. The rate of vesicle acidification was directly proportional to the concentration of nitrite that was added and the imposed pH difference across the membrane. In contrast, added nitrate had no effect on vesicle acidification. Nitrite also caused acidification of asolectin vesicles that were prepared by extrusion were approximately the same size, allowing them to be compared when the final extent of acidification, measured after the pH gradient had collapsed, was similar. The rate of nitrite-dependent acidification was similar in these two preparations at any single nitrite concentration. These results indicate that nitrite movement occurs by rapid diffusion across membranes as nitrous acid, and this movement is dependent on a proton gradient across the lipid bilayer. Under conditions approximating these in vivo, the rate of diffusion of nitrous acid far exceeds that of nitrite reduction within chloroplasts. 26 refs., 5 figs., 1 tab.

Shingles, R.; Roh, M.H.; McCarty, R.E. [Johns Hopkins Univ., Baltimore, MD (United States)

1996-11-01T23:59:59.000Z

103

Measuring photometric and spectral radiometric bi-directional transmission and reflection in a video-goniospectrometer  

E-Print Network (OSTI)

The effective use of complex fenestration systems (CFS) in buildings requires a detailed knowledge of their optical spectral and directional properties. Bidirectional scattering functions (BSDFs), either in transmission ...

Stokes, Eleanor (Eleanor Catherine)

2008-01-01T23:59:59.000Z

104

Direct measurement of B(D{sub s}{sup +}{r_arrow}{phi}X{sup +})  

Science Conference Proceedings (OSTI)

The absolute inclusive branching fraction of D{sub s}{sup +}{r_arrow}{phi}X{sup +} has been measured from data collected by the BES detector at a center-of-mass energy of 4.03 GeV, corresponding to an integrated luminosity of 22.3 pb{sup {minus}1}. At this energy, direct pair production e{sup +}e{sup {minus}}{r_arrow}D{sub s}{sup +}D{sub s}{sup {minus}} has been observed. We have selected D{sub s} candidate events by reconstructing five hadronic decay modes D{sub s}{sup +}{r_arrow}{phi}{pi}{sup +}, {bar K}{sup 0{asterisk}}K{sup +}, {bar K}{sup 0}K{sup +}, f{sub 0}{pi}{sup +} and K{sup 0}K{sup {minus}}{pi}{sup +}{pi}{sup +} and have searched for inclusive {phi}{close_quote}s in the recoiling D{sub s}{sup {minus}}. We observed three recoiling {phi}{close_quote}s in the 166.4 {plus_minus} 31.8 D{sub s} candidate events, which leads to the absolute branching fraction B(D{sub s}{sup +}{r_arrow}{phi}X{sup +})=(17.8{sub {minus}7.2}{sup +15.1}{sub {minus}6.3}{sup +0.6}) {percent} and B(D{sub s}{sup +}{r_arrow}{phi}{pi}{sup +})=(3.6{sub {minus}1.6}{sup +3.1}{sub {minus}1.3}{sup +0.4}) {percent}. {copyright} {ital 1997} {ital The American Physical Society}

Bai, J.Z.; Chen, G.P.; Chen, S.J.; Chen, S.M.; Chen, Y.; Chen, Y.B.; Chen, Y.Q.; Cheng, B.S.; Cui, X.Z.; Ding, H.L.; Du, Z.Z.; Fan, X.L.; Fang, J.; Gao, C.S.; Gao, M.L.; Gao, S.Q.; Gu, J.H.; Gu, S.D.; Gu, W.X.; Gu, Y.F.; Guo, Y.N.; Han, S.W.; Han, Y.; He, J.; Hu, G.Y.; Hu, T.; Hu, X.Q.; Huang, D.Q.; Huang, Y.Z.; Jiang, C.H.; Jin, S.; Jin, Y.; Kang, S.H.; Ke, Z.J.; Lai, Y.F.; Lan, H.B.; Lang, P.F.; Li, F.; Li, J.; Li, P.Q.; Li, R.B.; Li, W.; Li, W.D.; Li, W.G.; Li, X.H.; Li, X.N.; Lin, S.Z.; Liu, H.M.; Liu, J.; Liu, J.H.; Liu, Q.; Liu, R.G.; Liu, Y.; Liu, Z.A.; Lu, J.G.; Lu, J.Y.; Luo, S.; Luo, Y.; Ma, A.M.; Ma, E.C.; Ma, J.M.; Mao, H.S.; Mao, Z.P.; Meng, X.C.; Ni, H.L.; Nie, J.; Qi, N.D.; Que, Y.K.; Rong, G.; Shao, Y.Y.; Shen, D.L.; Shen, H.; Shen, X.Y.; Sheng, H.Y.; Shi, H.Z.; Song, X.F.; Sun, F.; Sun, H.S.; Sun, S.J.; Tan, Y.P.; Tang, S.Q.; Tong, G.L.; Wang, F.; Wang, L.S.; Wang, L.Z.; Wang, M.; Wang, P.; Wang, P.L.; Wang, S.M.; Wang, T.J.; Wang, Y.Y.; Wei, C.L.; Xi, D.M.; Xia, X.M.; Xie, P.P.; Xu, D.Z.; Xu, R.S.; Xu, Z.Q.; Xue, S.T.; Yan, J.; Yan, W.G.; Yang, C.M.; Yang, C.Y.; Ye, M.H.; Ye, S.Z.; Yu, C.S.; Yu, C.X.; Yu, Z.Q.; Yuan, C.Z.; Zhang, B.Y.; Zhang, C.C.; Zhang, D.H.; Zhang, H.L.; Zhang, J.; Zhang, J.W.; Zhang, L.S.; Zhang, S.Q.; Zhang, Y.; Zhang, Y.Y.; Zhao, D.X.; Zhao, J.W.; Zhao, M.; Zhao, W.R.; Zheng, J.P.; Zheng, L.S.; Zheng, Z.P.; Zhou, G.P.; Zhou, H.S.; Zhou, L.; Zhou, X.F.; Zhou, Y.H.; Zhu, Q.M.; Zhu, Y.C.; Zhu, Y.S.; Zhuang, B.A. [Institute of High Energy Physics, Beijing 100039, Peoples Republic of (China)] [Institute of High Energy Physics, Beijing 100039, Peoples Republic of (China); Hitlin, D.G.; Jones, L.; Kelsey, M.H.; Oyang, J.; Panetta, J.; Porter, F.; Prabhakar, E.; Weaver, M. [California Institute of Technology, Pasadena, California 91125 (United States)] [California Institute of Technology, Pasadena, California 91125 (United States); Chen, H.F. [Chinas University of Science and Technology, Hefei 230026, Peoples Republic of (China)] [Chinas University of Science and Technology, Hefei 230026, Peoples Republic of (China); Chen, J.; Malchow, R.; Toki, W.; Yang, W. [Colorado State University, Fort Collins, Colorado 80523 (United States)] [Colorado State University, Fort Collins, Colorado 80523 (United States); and others

1998-01-01T23:59:59.000Z

105

Airborne Measurements of the Wavenumber Spectra of Ocean Surface Waves. Part II: Directional Distribution  

Science Conference Proceedings (OSTI)

An airborne scanning lidar system acquires three-dimensional (3D) spatial topography of ocean surface waves. From the spatial data, wavenumber spectra are computed directly. The spectral properties in terms of the spectral slope and dimensionless ...

Paul A. Hwang; David W. Wang; Edward J. Walsh; William B. Krabill; Robert N. Swift

2000-11-01T23:59:59.000Z

106

The Effect of Directional Radiation Models on the Interpretation of Earth Radiation Budget Measurements  

Science Conference Proceedings (OSTI)

A parameter estimation technique is presented to estimate the radiative flux density distribution over the earn from a set of radiometer measurements at satellite altitude. The technique analyzes measurements from a wide field of view, horizon to ...

Richard N. Green

1980-10-01T23:59:59.000Z

107

Direct measurement of the cross-shock electric potential at low plasma $?$, quasi-perpendicular bow shocks  

E-Print Network (OSTI)

We use the Cluster EFW experiment to measure the cross-shock electric field at ten low $\\beta$, quasi-perpendicular supercritical bow shock crossings on March 31, 2001. The electric field data are Lorentz-tranformed to a Normal Incidence frame (NIF), in which the incoming solar wind velocity is aligned with the shock normal. In a boundary normal coordinate system, the cross-shock (normal) electric field is integrated to obtain the cross shock potential. Using this technique, we measure the cross-shock potential at each of the four Cluster satellites and using an electric field profile averaged between the four satellites. Typical values are in the range 500-2500 volts. The cross-shock potential measurements are compared with the ion kinetic energy change across the shock. The cross-shock potential is measured to be from 23 to 236% of the ion energy change, with large variations between the four Cluster spacecraft at the same shock. These results indicate that solar wind flow through the shock is likely to be variable in time and space and resulting structure of the shock is therefore nonstationary.

S. D. Bale; F. S. Mozer; V. V. Krasnoselskikh

2008-09-15T23:59:59.000Z

108

A New Method for the Measurement of the Site Errors of a Lightning Direction-Finder: Description and First Results  

Science Conference Proceedings (OSTI)

One of the major limitations in the use of magnetic direction-finders for locating lightning is the presence of systematic angle errors that are due to the local antenna site. An attempt was made to measure this systematic error, by using a ...

Th Schütte; E. Pisler; S. Israelsson

1987-06-01T23:59:59.000Z

109

Seasonal Variation of Aerosol Direct Radiative Forcing and Optical Properties Estimated from Ground-Based Solar Radiation Measurements  

Science Conference Proceedings (OSTI)

The surface direct radiative forcing and optical properties of aerosols have been analyzed from a ground-based solar radiation measurement, which was made under clear-sky conditions in Tsukuba, Japan, over two years from April 1997 to March 1999. ...

Tomoaki Nishizawa; Shoji Asano; Akihiro Uchiyama; Akihiro Yamazaki

2004-01-01T23:59:59.000Z

110

Feasibility of direct reactivity measurement in multi-canister overpacks at the Cold Vacuum Drying Facility  

DOE Green Energy (OSTI)

A proposed method for measuring the chemical reaction rate (power) of breached N-Reactor fuel elements with water in a Multi-canister overpack (MCO) based on hydrogen release rate is evaluated. The reaction rate is measured at 50 C in an oxygen free water by applying a vacuum to boil the water and adding a low, measured flow of helium. The ratio of helium to hydrogen is used to infer the reaction rate. A test duration of less than 8 hours was found to provide sufficient accuracy for confidence in the measurement results. A more rigorous treatment of system measurement accuracy, which may yield shorter test durations, should be performed if this reactivity measurement is to be employed.

Cowan, R.G.

1997-10-02T23:59:59.000Z

111

Measurement of Ocean Wave Directional Spectra Using Doppler Side-Scan Sonar Arrays  

Science Conference Proceedings (OSTI)

A technique is presented for extraction of ocean wave directional spectra using Doppler side-scan sonars. Two 103-kHz steerable side-scan beams from a freely drifting subsurface platform are used to estimate horizontal water surface velocity due ...

Mark V. Trevorrow

1995-06-01T23:59:59.000Z

112

A Comparison of VHF Radar Vertical-Velocity Measurements by a Direct Vertical-Beam Method and by a VAD Technique  

Science Conference Proceedings (OSTI)

Vertical-velocity measurements made by a direct vertical-beam method are compared to vertical velocities derived from VAD (velocity-azimuth display) measurements over a 27-h period. The results indicate that the two types of measurements in ...

M. F. Larsen; S. Fukao; O. Aruga; M. D. Yamanaka; T. Tsuda; S. Kato

1991-12-01T23:59:59.000Z

113

Direct measurement of product of the electron mobility and mean free drift time of CdZnTe semiconductors using position sensitive single  

E-Print Network (OSTI)

Direct measurement of product of the electron mobility and mean free drift time of Cd Institute of Physics. Related Articles A new detector for mass spectrometry: Direct detection of low energy://jap.aip.org/about/rights_and_permissions #12;Direct measurement of product of the electron mobility and mean free drift time of Cd

He, Zhong

114

Direct measurements of heat output by marine microbial and phage communities  

E-Print Network (OSTI)

was simulated by introducing a carefully measured quantity of electrical energy (Djamali 2005). A simplified) Thermochim. Acta, 397: 31. Mukhanov, V.S., Naidanova, O.G., Shadrin, N.V., and Kemp, R.B., (2004) Aquat. Ecol

Salamon, Peter

115

Hydraulic Interpretation of Direct Velocity Measurements in the Bab al Mandab  

Science Conference Proceedings (OSTI)

Acoustic Doppler Current Profiler velocity measurements in the Bab al Mandab during the period June 1995–March 1996 are used to assess the hydraulic character of the exchange flow. The strait is 150 km long and contains two distinct geometrical ...

L. J. Pratt; William Johns; Stephen P. Murray; Katsurou Katsumata

1999-11-01T23:59:59.000Z

116

Eddy Variability and Energetics from Direct Current Measurements in the Antarctic Circumpolar Current South of Australia  

Science Conference Proceedings (OSTI)

Two-year time series measurements of current velocity and temperature in the Subantarctic Front (SAF) south of Australia from 1993 to 1995 provide estimates of eddy fluxes of heat and momentum across the Antarctic Circumpolar Current (ACC) and ...

Helen E. Phillips; Stephen R. Rintoul

2000-12-01T23:59:59.000Z

117

In-situ permeability measurements with direct push techniques: Phase II topical report  

SciTech Connect

This effort designed, fabricated, and field tested the engineering prototype of the Cone Permeameter{trademark} system. The integrated system includes the instrumented penetrometer probe, air and water pumps, flowrate controls, flow sensors, and a laptop-controlled data system. All of the equipment is portable and can be transported as luggage on airlines. The data system acquired and displays the process measurements (pressures, flows, and downhole temperature) in real time and calculates the resulting permeability. The measurement probe is a 2 inch diameter CPT rod section, incorporating a screened injection zone near the lower end of the rod and multiple sensitive absolute pressure sensors embedded in the probe at varying distances from the injection zone. Laboratory tests in a large test cell demonstrated the system's ability to measure nominally 1 Darcy permeability soil (30 to 40 Darcy material had been successfully measured in the Phase 1 effort). These tests also provided a shakedown of the system and identified minor instrument problems, which were resolved. Supplemental numerical modeling was conducted to evaluate the effects of layered permeability (heterogeneity) and anisotropy on the measurement system's performance. The general results of the analysis were that the Cone Permeameter could measure accurately, in heterogeneous media, the volume represented by the sample port radii if the outer pressure ports were used. Anisotropic permeability, while readily analyzed numerically, is more complicated to resolve with the simple analytical approach of the 1-D model, and will need further work to quantify. This phase culminated in field demonstrations at the DOE Savannah River Site. Saturated hydraulic conductivity measurements were completed at the D-Area Coal Pile Runoff Basin, and air permeability measurements were conducted at the M Area Integrated Demonstration Site and the 321 M area. The saturated hydraulic conductivity measurements were the most successful and compared well to relevant existing data. Air permeability measurements were more problematic, primarily due to clay covering pressure measuring ports and preventing pressure communication with the sensors. Very little discreet air permeability data existed for the sites.

Lowry, W.; Mason, N.; Chipman, V.; Kisiel, K.; Stockton, J.

1999-03-01T23:59:59.000Z

118

Direct Measurement of EGR Cooler Deposit Thermal Properties for Improved Understanding of Cooler Fouling  

DOE Green Energy (OSTI)

Exhaust gas recirculation (EGR) cooler fouling has become a significant issue for compliance with NOX emissions standards. This paper reports results of a study of fundamental aspects of EGR cooler fouling. An apparatus and procedure were developed to allow surrogate EGR cooler tubes to be exposed to diesel engine exhaust under controlled conditions. The resulting fouled tubes were removed and analyzed. Volatile and non-volatile deposit mass was measured for each tube. Thermal diffusivity of the deposited soot cake was measured by milling a window into the tube and using the Xenon flash lamp method. The heat capacity of the deposit was measured at temperatures up to 430 C and was slightly higher than graphite, presumably due to the presence of hydrocarbons. These measurements were combined to allow calculation of the deposit thermal conductivity, which was determined to be 0.041 W/mK, only ~1.5 times that of air and much lower than the 304 stainless steel tube (14.7 W/mK). The main determinant of the deposit thermal conductivity is density, which was measured to be just 2% that of the density of the primary soot particles (or 98% porous). The deposit layer thermal resistance was calculated and compared with estimates of the thermal resistance calculated from gas temperature data during the experiment. The deposit properties were also used to further analyze the temperature data collected during the experiment.

Wang, Hsin [ORNL; Sluder, Scott [ORNL; Storey, John Morse [ORNL

2009-01-01T23:59:59.000Z

119

Band-gap measurements of direct and indirect semiconductors using monochromated electrons  

Science Conference Proceedings (OSTI)

With the development of monochromators for transmission electron microscopes, valence electron-energy-loss spectroscopy (VEELS) has become a powerful technique to study the band structure of materials with high spatial resolution. However, artifacts such as Cerenkov radiation pose a limit for interpretation of the low-loss spectra. In order to reveal the exact band-gap onset using the VEELS method, semiconductors with direct and indirect band-gap transitions have to be treated differently. For direct semiconductors, spectra acquired at thin regions can efficiently minimize the Cerenkov effects. Examples of hexagonal GaN (h-GaN) spectra acquired at different thickness showed that a correct band-gap onset value can be obtained for sample thicknesses up to 0.5 t/{lambda}. In addition, {omega}-q maps acquired at different specimen thicknesses confirm the thickness dependency of Cerenkov losses. For indirect semiconductors, the correct band-gap onset can be obtained in the dark-field mode when the required momentum transfer for indirect transition is satisfied. Dark-field VEEL spectroscopy using a star-shaped entrance aperture provides a way of removing Cerenkov effects in diffraction mode. Examples of Si spectra acquired by displacing the objective aperture revealed the exact indirect transition gap E{sub g} of 1.1 eV.

Gu Lin; Srot, Vesna; Sigle, Wilfried; Koch, Christoph; Aken, Peter van; Ruehle, Manfred [Max-Planck Institute for Metals Research, Heisenbergstrasse 3, D-70569 Stuttgart (Germany); Scholz, Ferdinand; Thapa, Sarad B.; Kirchner, Christoph [Institute of Optoelectronics, University of Ulm, Albert-Einstein-Allee 45, D-89069 Ulm (Germany); Jetter, Michael [Institut fuer Strahlenphysik, University of Stuttgart, D-70569 Stuttgart (Germany)

2007-05-15T23:59:59.000Z

120

Direct measurement of the impulse in a magnetic thrust chamber system for laser fusion rocket  

Science Conference Proceedings (OSTI)

An experiment is conducted to measure an impulse for demonstrating a magnetic thrust chamber system for laser fusion rocket. The impulse is produced by the interaction between plasma and magnetic field. In the experiment, the system consists of plasma and neodymium permanent magnets. The plasma is created by a single-beam laser aiming at a polystyrene spherical target. The impulse is 1.5 to 2.2 {mu}Ns by means of a pendulum thrust stand, when the laser energy is 0.7 J. Without magnetic field, the measured impulse is found to be zero. These results indicate that the system for generating impulse is working.

Maeno, Akihiro; Yamamoto, Naoji; Nakashima, Hideki [Interdisciplinary Graduate School of Engineering Science, Kyushu University, 6-1 Kasuga-kouen, Kasuga, Fukuoka 816-8580 (Japan); Fujioka, Shinsuke; Johzaki, Tomoyuki [Institute of Laser Engineering, Osaka University, Suita, Osaka 565-087 (Japan); Mori, Yoshitaka [Graduate School for the Creation of New Photonics Industries, Hamamatsu, Shizuoka 431-1202 (Japan); Sunahara, Atsushi [Institute for Laser Technology, Suita, Osaka 565-087 (Japan)

2011-08-15T23:59:59.000Z

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


121

Charged particle directed flow in Pb-Pb collisions at sqrt{s_NN} = 2.76 TeV measured with ALICE at the LHC  

E-Print Network (OSTI)

Charged particle directed flow at midrapidity, |eta|Directed flow is reported as a function of collision centrality, charged particle transverse momentum, and pseudo-rapidity. Results are compared to measurements at RHIC and recent model calculations for LHC energies.

Ilya Selyuzhenkov; for the ALICE Collaboration

2011-06-27T23:59:59.000Z

122

Kinetics of HEX-BCC Transition in a Triblock Copolymer in a Selective Solvent: Time Resolved Small Angle X-ray Scattering Measurements and Model Calculations  

E-Print Network (OSTI)

Time-resolved small angle x-ray scattering (SAXS) was used to examine the kinetics of the transition from HEX cylinders to BCC spheres at various temperatures in poly(styrene-b- ethylene-co-butylene-b-styrene) (SEBS) in mineral oil, a selective solvent for the middle EB block. Temperature-ramp SAXS and rheology measurements show the HEX to BCC order-order transition (OOT) at ~127 oC and order-disorder transition (ODT) at ~180 oC. We also observed the metastability limit of HEX in BCC with a spinodal temperature, Ts ~ 150 oC. The OOT exhibits 3 stages and occurs via a nucleation and growth mechanism when the final temperature Tf peak into two peaks when the cylinder spacing and modulation wavelength are incommensurate predicted by the model is confirmed by analysis of the SAXS data.

Minghai Li; Yongsheng Liu; Huifen Nie; Rama Bansil; Milos Steinhart

2007-10-24T23:59:59.000Z

123

Direct Measurement of the Free Energy of Aging Hard-Sphere Colloidal Glasses  

E-Print Network (OSTI)

The nature of the glass transition is one of the most important unsolved problems in condensed matter physics. The difference between glasses and liquids is believed to be caused by very large free energy barriers for particle rearrangements; however so far it has not been possible to confirm this experimentally. We provide the first quantitative determination of the free energy for an aging hard-sphere colloidal glass. The determination of the free energy allows for a number of new insights in the glass transition, notably the quantification of the strong spatial and temporal heterogeneity in the free energy. A study of the local minima of the free energy reveals that the observed variations are directly related to the rearrangements of the particles. Our main finding is that the probability of particle rearrangements shows a power law dependence on the free energy changes associated with the rearrangements, similarly to the Gutenberg-Richter law in seismology.

Rojman Zargar; Bernard Nienhuis; Peter Schall; Daniel Bonn

2013-03-17T23:59:59.000Z

124

Comparing Pulsed Doppler LIDAR with SODAR and Direct Measurements for Wind Assessment  

DOE Green Energy (OSTI)

There is a pressing need for good wind-speed measurements at greater and greater heights to assess the availability of the resource in terms of power production and to identify any frequently occurring atmospheric structural characteristics that may create turbulence that impacts the operational reliability and lifetime of wind turbines and their components. In this paper, we summarize the results of a short study that compares the relative accuracies of wind speeds derived from a high-resolution pulsed Doppler LIDAR operated by the National Oceanic and Atmospheric Administration (NOAA) and a midrange Doppler SODAR with wind speeds measured by four levels of tower-based sonic anemometry up to a height of 116 m.

Kelley, N. D.; Jonkman, B. J.; Scott, G. N.; Pichugina, Y. L.

2007-07-01T23:59:59.000Z

125

Measurement of Vertical Kinetic Energy and Vertical Velocity Skewness in Oceanic Boundary Layers by Imperfectly Lagrangian Floats  

Science Conference Proceedings (OSTI)

The effects of upward buoyancy on the accuracy with which Lagrangian floats can measure the Eulerian mean variance wwE and skewness SwE of vertical fluid velocity w in the wind-driven upper-ocean boundary layer is investigated using both ...

Ramsey R. Harcourt; Eric A. D’Asaro

2010-11-01T23:59:59.000Z

126

Direct measurement of concurrence for atomic two-qubit pure states  

Science Conference Proceedings (OSTI)

We propose a general scheme to measure the concurrence of an arbitrary two-qubit pure state in atomic systems. The protocol is based on one- and two-qubit operations acting on two available copies of the bipartite system, and followed by a global qubit readout. We show that it is possible to encode the concurrence in the probability of finding all atomic qubits in the ground state. Two possible scenarios are considered: atoms crossing three-dimensional microwave cavities and trapped ion systems.

Romero, G.; Lopez, C. E.; Lastra, F.; Retamal, J. C. [Departamento de Fisica, Universidad de Santiago de Chile, Casilla 307 Correo 2, Santiago (Chile); Solano, E. [Physics Department, ASC, and CeNS, Ludwig-Maximilians-Universitaet, Theresienstrasse 37, D-80333 Munich (Germany); Seccion Fisica, Departamento de Ciencias, Pontificia Universidad Catolica del Peru, Apartado 1761, Lima (Peru)

2007-03-15T23:59:59.000Z

127

Determination of Optical-Field Ionization Dynamics in Plasmas through the Direct Measurement of the Optical Phase Change  

DOE Green Energy (OSTI)

This is the final report of a three-year Laboratory Directed Research and Development (LDRD) Project at Los Alamos National Laboratory (LANL). The detailed dynamics of an atom in a strong laser field is rich in both interesting physics and potential applications. The goal of this project was to develop a technique for characterizing high-field laser-plasma interactions with femtosecond resolution based on the direct measurement of the phase change of an optical pulse. The authors developed the technique of Multi-pulse Interferometric Frequency Resolved Optical Gating (MI-FROG), which recovers (to all orders) the phase difference between pumped and unpumped probe pulses, enabling the determination of sub-pulsewidth time-resolved phase and frequency shifts impressed by a pump pulse on a weak probe pulse. Using MI-FROG, the authors obtained the first quantitative measurements of high-field ionization rates in noble gases and diatomic molecules. They obtained agreement between the measured ionization rates an d those calculated for the noble gases and diatomic nitrogen and hydrogen using a one-dimensional fluid model and rates derived from tunneling theory. However, much higher rates are measured for diatomic oxygen than predicted by tunneling theory calculations.

Taylor, A.J.; Omenetto, G.; Rodriguez, G.; Siders, C.W.; Siders, J.L.W.; Downer, C.

1999-07-16T23:59:59.000Z

128

The combustion chemistry of a fuel tracer: Measured flame speeds and ignition delays and a detailed chemical kinetic model for the oxidation of acetone  

SciTech Connect

Acetone ignition delay and stretch-free laminar flame speed measurements have been carried out and a kinetic model has been developed to simulate these and literature data for acetone and for ketene, which was found to be an important intermediate in its oxidation. The mechanism has been based on one originally devised for dimethyl ether and modified through validation of the hydrogen, carbon monoxide and methane sub-mechanisms. Acetone oxidation in argon was studied behind reflected shock waves in the temperature range 1340-1930 K, at 1 atm and at equivalence ratios of 0.5, 1 and 2; it is also shown that the addition of up to 15% acetone to a stoichiometric n-heptane mixture has no effect on the measured ignition delay times. Flame speeds at 298 K and 1 atm of pure acetone in air were measured in a spherical bomb; a maximum flame speed of {proportional_to}35 cm s{sup -1} at {phi}=1.15 is indicated. (author)

Pichon, S.; Black, G.; Simmie, J.M.; Curran, H.J. [Combustion Chemistry Centre, National University of Ireland, Galway (Ireland); Chaumeix, N.; Yahyaoui, M. [Institut de Combustion Aerothermique Reactivite et Environnement, CNRS, Orleans (France); Donohue, R. [Information Technology, National University of Ireland, Galway (Ireland)

2009-02-15T23:59:59.000Z

129

Direct measurements of the effects of salt and surfactant on interaction forces between colloidal particles at water-oil interfaces  

E-Print Network (OSTI)

The forces between colloidal particles at a decane-water interface, in the presence of low concentrations of a monovalent salt (NaCl) and of the surfactant sodium dodecylsulfate (SDS) in the aqueous subphase, have been studied using laser tweezers. In the absence of electrolyte and surfactant, particle interactions exhibit a long-range repulsion, yet the variation of the interaction for different particle pairs is found to be considerable. Averaging over several particle pairs was hence found to be necessary to obtain reliable assessment of the effects of salt and surfactant. It has previously been suggested that the repulsion is consistent with electrostatic interactions between a small number of dissociated charges in the oil phase, leading to a decay with distance to the power -4 and an absence of any effect of electrolyte concentration. However, the present work demonstrates that increasing the electrolyte concentration does yield, on average, a reduction of the magnitude of the interaction force with electrolyte concentration. This implies that charges on the water side also contribute significantly to the electrostatic interactions. An increase in the concentration of SDS leads to a similar decrease of the interaction force. Moreover the repulsion at fixed SDS concentrations decreases over longer times. Finally, measurements of three-body interactions provide insight into the anisotropic nature of the interactions. The unique time-dependent and anisotropic interactions between particles at the oil-water interface allow tailoring of the aggregation kinetics and structure of the suspension structure.

B. J. Park; J. P. Pantina; E. Furst; M. Oettel; S. Reynaert; J. Vermant

2007-09-07T23:59:59.000Z

130

A comparison of spanwise aerodynamic loads estimated from measured bending moments versus direct pressure measurements on horizontal axis wind turbine blades  

DOE Green Energy (OSTI)

Two methods can be used to determine aerodynamic loads on a rotating wind turbine blade. The first is to make direct pressure measurements on the blade surface. This is a difficult process requiring costly pressure instrumentation. The second method uses measured flap bending moments in conjunction with analytical techniques to estimate airloads. This method, called ALEST, was originally developed for use on helicopter rotors and was modified for use on horizontal axis wind turbine blades. Estimating airloads using flap bending moments in much simpler and less costly because measurements can be made with conventional strain gages and equipment. This paper presents results of airload estimates obtained using both methods under a variety of operating conditions. Insights on the limitations and usefulness of the ALEST bending moment technique are also included. 10 refs., 6 figs.

Simms, D A; Butterfield, C P

1991-10-01T23:59:59.000Z

131

Towards a direct transition energy measurement of the lowest nuclear excitation in 229Th  

E-Print Network (OSTI)

The isomeric first excited state of the isotope 229Th exhibits the lowest nuclear excitation energy in the whole landscape of known atomic nuclei. For a long time this energy was reported in the literature as 3.5(5) eV, however, a new experiment corrected this energy to 7.6(5) eV, corresponding to a UV transition wavelength of 163(11) nm. The expected isomeric lifetime is $\\tau=$ 3-5 hours, leading to an extremely sharp relative linewidth of Delta E/E ~ 10^-20, 5-6 orders of magnitude smaller than typical atomic relative linewidths. For an adequately chosen electronic state the frequency of the nuclear ground-state transition will be independent from influences of external fields in the framework of the linear Zeeman and quadratic Stark effect, rendering 229mTh a candidate for a reference of an optical clock with very high accuracy. Moreover, in the literature speculations about a potentially enhanced sensitivity of the ground-state transition of $^{229m}$Th for eventual time-dependent variations of fundamental constants (e.g. fine structure constant alpha) can be found. We report on our experimental activities that aim at a direct identification of the UV fluorescence of the ground-state transition energy of 229mTh. A further goal is to improve the accuracy of the ground-state transition energy as a prerequisite for a laser-based optical control of this nuclear excited state, allowing to build a bridge between atomic and nuclear physics and open new perspectives for metrological as well as fundamental studies.

L. v. d. Wense; P. G. Thirolf; D. Kalb; M. Laatiaoui

2012-11-04T23:59:59.000Z

132

Kinetic Economies  

E-Print Network (OSTI)

We study a minimalist kinetic model for economies. A system of agents with local trading rules display emergent demand behaviour. We examine the resulting wealth distribution to look for non-thermal behaviour. We compare and contrast this model with other similar models.

Abdullah, Wan Ahmad Tajuddin Wan

2007-01-01T23:59:59.000Z

133

First direct measurement of resonance strengths in {sup 17}O({alpha},{gamma}){sup 21}Ne  

SciTech Connect

The reaction {sup 17}O({alpha},{gamma}){sup 21}Ne has been measured by in-beam {gamma} spectroscopy for the first time in the energy range E{sub {alpha}=}750-1650 keV using highly enriched anodized Ta{sub 2}({sup 17}O){sub 5} targets. Resonances were found at E{sub {alpha}=} 1002, 1386, and 1619 keV. Their strengths and primary {gamma}-ray branchings are given. The new results exclude the low reaction rate of Descouvemont and support the rate of Caughlan and Fowler. Implications for the neutron poisoning efficiency of {sup 16}O in the weak s-process are discussed.

Best, A.; Goerres, J.; Couder, M.; Boer, R. de; Falahat, S.; Kontos, A.; LeBlanc, P. J.; Li, Q.; O'Brien, S.; Sonnabend, K.; Talwar, R.; Uberseder, E.; Wiescher, M. [Department of Physics, University of Notre Dame, Notre Dame, Indiana 46556 (United States)

2011-05-15T23:59:59.000Z

134

Fuels Performance Technologies: Milestone FY06 9.1 -- Using IQT measurements, develop simplified kinetic expressions for ignition of fuels that could be used in HCCI engine models  

DOE Green Energy (OSTI)

Discusses the development of a new fuel characterization, based on simplified kinetic expression, to quantify ignition quality for low-temperature combustion vehicle applications.

Taylor, J. D.

2006-11-01T23:59:59.000Z

135

Laser-induced fluorescence measurements and kinetic analysis of Si atom formation in a rotating disk chemical vapor deposition reactor  

SciTech Connect

An extensive set of laser-induced fluorescence (LIF) measurements of Si atoms during the chemical vapor deposition (CVD) of silicon from silane and disilane in a research rotating disk reactor are presented. The experimental results are compared in detail with predictions from a numerical model of CVD from silane and disilane that treats the fluid flow coupled to gas-phase and gas-surface chemistry. The comparisons showed that the unimolecular decomposition of SiH[sub 2] could not account for the observed gas-phase Si atom density profiles. The H[sub 3]SiSiH [leftrightarrow] Si + SiH[sub 4] and H[sub 3]SiSiH + SiH[sub 2] [leftrightarrow] Si + Si[sub 2]H[sub 6] reactions are proposed as the primary Si atom production routes. The model is in good agreement with the measured shapes of the Si atom profiles and the trends in Si atom density with susceptor temperature, pressure, and reactant gas mixture. 33 refs., 12 figs., 3 tabs.

Ho, P.; Coltrin, M.E.; Breiland, W.G. (Sandia National Lab., Albuquerque, NM (United States))

1994-10-06T23:59:59.000Z

136

Development of a Standard Methodology for the Quantitative Measurement of Steel Phase Transformation Kinetics and Dilation Strains Using Dilatometric Methods, QMST (TRP 0015)  

Science Conference Proceedings (OSTI)

The purpose of this collaborative project was to develop a standard practice for obtaining and archiving quantitative steel transformation kinetic data and thermal strain data. Two families of dilatometric equipment were employed to develop this standard practice for testing bar product steels. These include high-speed quenching and deformation dilatometers and Gleeble{reg_sign} thermomechanical simulation instruments. Standard measurement, data interpretation and data reporting methods were developed and defined by the cross-industry QMST Consortium members consisting of steel-manufacturers, forgers, heat-treaters, modelers, automotive and heavy vehicle OEMs along with team expert technologists from the National Labs and academia. The team designed phase transformation experiments on two selected steel grades to validate the standard practices--a medium carbon grade SAE 1050 and an alloy steel SAE 8620. A final standard practice document was developed based on the two dilatometry methods, and was submitted to and approved by ASTM (available as A1033-04). The standard practice specifies a method for measuring austenite transformation under no elastic stress or plastic deformation. These methods will be an enabler for the development and electronic archiving of a quantitative database for process modeling using computer simulation software, and will greatly assist endusers in developing accurate process and product simulations during the thermo-mechanical processing of bar and rod product steels.

Dr. Manish Metha; Dr. Tom Oakwood

2004-04-28T23:59:59.000Z

137

Atmospheric Radiation Measurement Program Science Plan Current Status and Future Directions of the ARM Science Program  

SciTech Connect

The Atmospheric Radiation Measurement (ARM) Program has matured into one of the key programs in the U.S. Climate Change Science Program. The ARM Program has achieved considerable scientific success in a broad range of activities, including site and instrument development, atmospheric radiative transfer, aerosol science, determination of cloud properties, cloud modeling, and cloud parameterization testing and development. The focus of ARM science has naturally shifted during the last few years to an increasing emphasis on modeling and parameterization studies to take advantage of the long time series of data now available. During the next 5 years, the principal focus of the ARM science program will be to: • Maintain the data record at the fixed ARM sites for at least the next five years. • Improve significantly our understanding of and ability to parameterize the 3-D cloud-radiation problem at scales from the local atmospheric column to the global climate model (GCM) grid square. • Continue developing techniques to retrieve the properties of all clouds, with a special focus on ice clouds and mixed-phase clouds. • Develop a focused research effort on the indirect aerosol problem that spans observations, physical models, and climate model parameterizations. • Implement and evaluate an operational methodology to calculate broad-band heating rates in the atmospheric columns at the ARM sites. • Develop and implement methodologies to use ARM data more effectively to test atmospheric models, both at the cloud-resolving model scale and the GCM scale. • Use these methodologies to diagnose cloud parameterization performance and then refine these parameterizations to improve the accuracy of climate model simulations. In addition, the ARM Program is actively developing a new ARM Mobile Facility (AMF) that will be available for short deployments (several months to a year or more) in climatically important regions. The AMF will have much of the same instrumentation as the remote facilities at ARM’s Tropical Western Pacific and the North Slope of Alaska sites. Over time, this new facility will extend ARM science to a much broader range of conditions for model testing.

TP Ackerman; AD Del Genio; RG Ellingson; RA Ferrare; SA Klein; GM McFarquhar; PJ Lamb; CN Long; J Verlinde

2004-10-30T23:59:59.000Z

138

Direct measurement of the 15N(p,gamma)16O total cross section at novae energies  

E-Print Network (OSTI)

The 15N(p,gamma)16O reaction controls the passage of nucleosynthetic material from the first to the second carbon-nitrogen-oxygen (CNO) cycle. A direct measurement of the total 15N(p,gamma)16O cross section at energies corresponding to hydrogen burning in novae is presented here. Data have been taken at 90-230 keV center-of-mass energy using a windowless gas target filled with nitrogen of natural isotopic composition and a bismuth germanate summing detector. The cross section is found to be a factor two lower than previously believed.

D Bemmerer; A Caciolli; R Bonetti; C Broggini; F Confortola; P Corvisiero; H Costantini; Z Elekes; A Formicola; Zs Fulop; G Gervino; A Guglielmetti; C Gustavino; Gy Gyurky; M Junker; B Limata; M Marta; R Menegazzo; P Prati; V Roca; C Rolfs; C Rossi Alvarez; E Somorjai; O Straniero

2009-02-04T23:59:59.000Z

139

Development of Simplified Calculations for a Multipyranometer Array for the Measurement of Direct and Diffuse Solar Radiation  

E-Print Network (OSTI)

This paper describes the development of simplified procedures for a multipyranometer array (MPA) for the continuous measurement of direct and diffuse solar radiation. The MPA described in this paper is an improvement over previously published MPA studies due several new features, including: the incorporation of an artificial horizon that prevents reflected ground radiation from striking the tilted sensors, and a routine that corrects the spectral response of photovoltaic-type sensors used in the MPA. An optimal solution procedure has also been developed that eliminates invalid data which are inherent in the simultaneous solution of the solar equations from the four MPA sensors. In this paper a description of the NIST-traceable calibration facility is provided and results are presented that compare the improved MPA-predicted beam to side-by-side measurements from a precision Normal Incidence Pyrheliometer (NIP).

Munger, B. K.; Haberl, J. S.

2000-01-01T23:59:59.000Z

140

Direct measurement of the {sup 18}F(p,{alpha}){sup 15}O reaction at nova temperatures  

SciTech Connect

The {sup 18}F(p,{alpha}){sup 15}O reaction rate is crucial for understanding the final abundance of {sup 18}F predicted by nova models. The {gamma}-ray emission in the first few hours after a nova outburst is expected to be dominated by 511 keV annihilation photons from the decay of {sup 18}F, and so understanding its production can provide important constraints on the conditions during the outburst when compared with observations. Results are presented from the lowest-energy direct measurement to date, performed at the Isotope Separator and Accelerator radioactive beam facility at the TRIUMF laboratory, Canada. Cross section measurements at center-of-mass energies of 250, 330, 453, and 673 keV are obtained and the results compared to previous data and R-matrix calculations. The implications for the overall reaction rate in the context of nova explosions have been discussed.

Beer, C. E.; Laird, A. M.; Bentley, M. A.; Diget, C. A.; Fox, S. P.; Fulton, B. R. [Department of Physics, University of York, York YO10 5DD (United Kingdom); Murphy, A. St. J.; Davinson, T.; Salter, P. [SUPA, School of Physics and Astronomy, University of Edinburgh, Edinburgh EH9 3JZ (United Kingdom); Buchman, L.; Davids, B.; Hager, U.; Howell, D.; Martin, L.; Ruiz, C.; Ruprecht, G.; Vockenhuber, C.; Walden, P. [TRIUMF, Vancouver, British Columbia V6T 2A3 (Canada)

2011-04-15T23:59:59.000Z

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


141

First Direct Measurement of the 17F(p,gamma)18Ne Cross Section  

SciTech Connect

The rate of the 17F(p,gamma)18Ne reaction is of significant importance in astrophysical events like novae and x-ray bursts. A previous 17F(p,p)17F measurement identified the 3+ state in 18Ne predicted to dominate the rate above 0.2 GK at a center of mass energy of 599.8 keV, but the resonance strength for proton capture was unknown. We have directly measured the 17F(p,gamma)18Ne reaction with the Daresbury Recoil Separator, using a mixed beam of radioactive 17F and stable 17O from the HRIBF at ORNL. The resonance strength for the 599.8 keV resonance in 18Ne was found to be = 33 14(stat) 17(sys) meV, corresponding to a width of = 56 24(stat) 30(sys) meV. Additionally, an upper limit on the direct capture S factor of S(E) < 65 keV b was determined at an intermediate energy of 800 keV.

Chipps, K. [Colorado School of Mines, Golden; Bardayan, Daniel W [ORNL; Blackmon, Jeff C [ORNL; Chae, K. Y. [University of Tennessee, Knoxville (UTK); Greife, U. [Colorado School of Mines, Golden; Hatarik, Robert [Rutgers University; Kozub, R. L. [Tennessee Technological University; Matei, Catalin [Oak Ridge Associated Universities (ORAU); Moazen, Brian [University of Tennessee, Knoxville (UTK); Nesaraja, Caroline D [ORNL; Pain, Steven D [ORNL; Peters, W. A. [Rutgers University; Pittman, S. T. [University of Tennessee, Knoxville (UTK); ShrinerJr., J. F. [Tennessee Technological University; Smith, Michael Scott [ORNL

2008-01-01T23:59:59.000Z

142

Electro-osmotic drag of water in ionomeric membranes. New measurements employing a direct methanol fuel cell  

Science Conference Proceedings (OSTI)

A direct methanol fuel cell (DMFC) employing a proton conducting membrane was used to determine the electro-osmotic drag coefficient of water in the ionomeric membrane. Water flux across the membrane in such a cell (operated with 1.0 M aqueous methanol at the anode and dry O{sub 2} at the cathode) is driven by protonic drag exclusively at sufficiently high current densities. This is evidenced experimentally by a linear relationship between cell current and flux of water measured crossing the membrane. Application of the DMFC for such water-drag measurements is significantly simpler experimentally than the approach described by the authors before, particularly so for measurements above room temperature. In measurements the authors performed in the DMFC configuration on Nafion 117 membranes, the water drag coefficient was found to increase with temperature, from 2.0 H{sub 2}O/H{sup +} at 15 C to 5.1 H{sub 2}O/H{sup +} at 130 C. Implications of these new results on water management in DMFCs are briefly discussed.

Ren, X.; Henderson, W.; Gottesfeld, S. [Los Alamos National Lab., NM (United States)

1997-09-01T23:59:59.000Z

143

DIRECT MEASUREMENT OF THE ANGULAR POWER SPECTRUM OF COSMIC MICROWAVE BACKGROUND TEMPERATURE ANISOTROPIES IN THE WMAP DATA  

Science Conference Proceedings (OSTI)

The angular power spectrum of the cosmic microwave background temperature anisotropies is one of the most important characteristics in cosmology that can shed light on the properties of the universe such as its geometry and total density. Using flat sky approximation and Fourier analysis, we estimate the angular power spectrum from an ensemble of the least foreground-contaminated square patches from the Wilkinson Microwave Anisotropy Probe W and V frequency band map. This method circumvents the issue of foreground cleaning and that of breaking orthogonality in spherical harmonic analysis because we are able to mask out the bright Galactic plane region, thereby rendering a direct measurement of the angular power spectrum. We test and confirm the Gaussian statistical characteristic of the selected patches, from which the first and second acoustic peaks of the power spectrum are reproduced, and the third peak is clearly visible, albeit with some noise residual at the tail.

Chiang, Lung-Yih [Institute of Astrophysics, National Taiwan University, 1, Rooservolt Road, Taipei, Taiwan (China); Chen, Fei-Fan, E-mail: lychiang@asiaa.sinica.edu.tw [Institute of Astronomy and Astrophysics, Academia Sinica, P.O. Box 23-141, Taipei 10617, Taiwan (China)

2012-05-20T23:59:59.000Z

144

High temperature thermal conductivity measurements of UO/sub 2/ by Direct Electrical Heating. Final report. [MANTRA-III  

SciTech Connect

High temperature properties of reactor type UO/sub 2/ pellets were measured using a Direct Electrical Heating (DEH) Facility. Modifications to the experimental apparatus have been made so that successful and reproducible DEH runs may be carried out while protecting the pellets from oxidation at high temperature. X-ray diffraction measurements on the UO/sub 2/ pellets have been made before and after runs to assure that sample oxidation has not occurred. A computer code has been developed that will model the experiment using equations that describe physical properties of the material. This code allows these equations to be checked by comparing the model results to collected data. The thermal conductivity equation for UO/sub 2/ proposed by Weilbacher has been used for this analysis. By adjusting the empirical parameters in Weilbacher's equation, experimental data can be matched by the code. From the several runs analyzed, the resulting thermal conductivity equation is lambda = 1/4.79 + 0.0247T/ + 1.06 x 10/sup -3/ exp(-1.62/kT/) - 4410. exp(-3.71/kT/) where lambda is in w/cm K, k is the Boltzman constant, and T is the temperature in Kelvin.

Bassett, B

1980-10-01T23:59:59.000Z

145

Televiewer measurement of in-situ stress direction at the Fenton Hill Hot Dry Rock Site, New Mexico  

DOE Green Energy (OSTI)

The in situ stresses at Fenton Hill has been determined in drill hole EE-3A by observations of wellbore breakouts on imagery obtained with a televiewer logging tool. Wellbore shape, tool offcentering, and tool misalignment cause geometric distortions which have been treated by comparing imagery from two logging runs made six months apart. The comparison establishes that wellbore degradation in drill hole EE-3A is due to breakouts, which grow larger with time. The azimuth of the axis of minimum horizontal principal stress is estimated to be 110.7 +//minus/ 10.3 deg E of true N at a depth of 11,500 ft, increasing with depth at a rate of 1 deg per 50 ft. This method of measuring the orientation of horizontal principal axes is considerably more accurate than previous methods tried at Fenton Hill. The results agree generally with other stress indicators. The results support the concept that direction of reservoir growth during hydraulic stimulation favours the intermediate axis over other principal axes of stress. 11 figs., 1 tab.

Burns, K.L.

1988-01-01T23:59:59.000Z

146

Plasma Kinetic Theory  

Science Conference Proceedings (OSTI)

Kinetic Theory / Proceedings of the Ninth Carolus Magnus Summer School on Plasma and Fusion Energy Physics

B. Weyssow

147

The Vertical Partition of Oceanic Horizontal Kinetic Energy  

Science Conference Proceedings (OSTI)

To produce an interpretation of the surface kinetic energy as measured by altimeters, a survey is made of the vertical structure of kinetic energy profiles in a large number of globally distributed long current meter records. Although the data ...

Carl Wunsch

1997-08-01T23:59:59.000Z

148

Apparatus and method for direct measurement of coal ash sintering and fusion properties at elevated temperatures and pressures  

SciTech Connect

A high-pressure microdilatometer is provided for measuring the sintering and fusion properties of various coal ashes under the influence of elevated pressures and temperatures in various atmospheres. Electrical resistivity measurements across a sample of coal ash provide a measurement of the onset of the sintering and fusion of the ash particulates while the contraction of the sample during sintering is measured with a linear variable displacement transducer for detecting the initiation of sintering. These measurements of sintering in coal ash at different pressures provide a mechanism by which deleterious problems due to the sintering and fusion of ash in various combustion systems can be minimized or obviated.

Khan, M. Rashid (Morgantown, WV)

1990-01-01T23:59:59.000Z

149

Apparatus and method for direct measurement of coal ash sintering and fusion properties at elevated temperatures and pressures  

DOE Patents (OSTI)

A high-pressure microdilatometer is provided for measuring the sintering and fusion properties of various coal ashes under the influence of elevated pressures and temperatures in various atmospheres. Electrical resistivity measurements across a sample of coal ash provide a measurement of the onset of the sintering and fusion of the ash particulates while the contraction of the sample during sintering is measured with a linear variable displacement transducer for detecting the initiation of sintering. These measurements of sintering in coal ash at different pressures provide a mechanism by which deleterious problems due to the sintering and fusion of ash in various combustion systems can be minimized or obviated. 7 figs.

Khan, M.R.

1989-05-12T23:59:59.000Z

150

SWIMSAT: A Real-Aperture Radar to Measure Directional Spectra of Ocean Waves from Space—Main Characteristics and Performance Simulation  

Science Conference Proceedings (OSTI)

The project SWIMSAT aims to measure the directional spectra of waves from space using a real-aperture radar with a low-incidence, conical-scanning beam. This system’s design is based on airborne versions developed in France and the United States. ...

Danièle Hauser; Elbatoul Soussi; Eric Thouvenot; Laurent Rey

2001-03-01T23:59:59.000Z

151

Measuring the relative efficiency of IC design firms using the directional distance function and a meta-frontier approach  

Science Conference Proceedings (OSTI)

This paper presents an alternative approach for evaluating the efficiency of integrated circuit (IC) design firms. In doing so, it accounts for differences between technology groups containing one or more design firms, and input and output factors to ... Keywords: Directional distance function, Group-frontier, IC design firm, Meta-frontier, Performance evaluations

Bo Hsiao; Ching-Chin Chern; Ming-Miin Yu

2012-11-01T23:59:59.000Z

152

Flow Measurement and Instrumentation 24 (2012) 4349 Contents lists available at SciVerse ScienceDirect  

E-Print Network (OSTI)

blends is widely seen in coal and biomass fired power stations. In 1979, the Bayfront plant in the US.elsevier.com/locate/flowmeasinst Concentration measurement of biomass/coal/air three-phase flow by integrating electrostatic and capacitive describes an integrated instrumentation system for the volumetric-concentration measure- ment of biomass/coal

Yan, Yong

153

Plasma Kinetic Theory  

Science Conference Proceedings (OSTI)

Basic and Kinetic Theory / Proceedings of the Tenth Carolus Magnus Summer School on Plasma and Fusion Energy Physics

B. Weyssow

154

Computational Thermodynamics and Kinetics  

Science Conference Proceedings (OSTI)

Jul 31, 2011 ... About this Symposium. Meeting, 2012 TMS Annual Meeting & Exhibition. Symposium, Computational Thermodynamics and Kinetics.

155

Chapter 13. Chemical Kinetics  

E-Print Network (OSTI)

of chemical reactions. · Only gases, for which the kinetic theory of Chapter 4 is applicable, are consideredChapter 13. Chemical Kinetics #12;· Why do some chemical reactions proceed with lighting speed when the way in which molecules combine to form products? · All of these questions involve chemical kinetics

Ihee, Hyotcherl

156

Direct measurement of strontium-90 and uranium-238 in soils on a real-time basis: 1994 summary report  

Science Conference Proceedings (OSTI)

Traditional methodologies for quantitative characterization of radionuclide-contaminated soils over extended areas are often tedious, costly, and non-representative. A rapid characterization methodology was designed that provides reliable output with spatial resolution on the order of a few meters or less. It incorporates an innovative sensor of square plastic scintillating fibers that has been designed to be placed directly on or above a contaminated soil to detect and quantify high-energy beta particles associated with the decay chains of uranium and/or strontium. Under the direction and auspices of the DOE`s Characterization, Monitoring, and Sensor Technology Integrated Program, Pacific Northwest Laboratory (PNL) constructed a high-energy beta scintillation sensor that was optimized for the detection and quantification of uranium and strontium contamination in surface soils (in the presence of potentially interfering natural and anthropogenic radionuclides), demonstrated and evaluated this detector in various field and laboratory scenarios, and provides this document in completion of the aforementioned requirements.

Schilk, A.J.; Hubbard, C.W.; Knopf, M.A.; Thompson, R.C.

1995-04-01T23:59:59.000Z

157

Direct Total Cross Section Measurement of the 16O(?,?)20Ne Reaction at Ec.m. = 2.26 MeV  

Science Conference Proceedings (OSTI)

In stellar helium burning, (16)O represents the endpoint of the helium-burning sequence due to the low rate of (16)O(alpha,gamma)(20)Ne. We present a new direct measurement of the total capture reaction rate of (16)O(alpha,gamma)(20)Ne at E(c.m.) = 2.26MeV employing the DRAGON recoil separator. For the first time, the total S factor and its contributing direct capture transitions could be determined in one experiment.

Hager, Ulrike; Brown, James R.; Buchmann, Lothar R.; Carmona-Gallardo, Mariano; Erikson, Luke E.; Fallis, Jennifer S.; Greife, Uwe; Hutcheon, Dave; Ottewell, Dave; Ruiz, Chris; Sjue, Sky; Vockenhuber, Cristof

2011-08-23T23:59:59.000Z

158

Rainfall Kinetic Energy in Eastern Australia  

Science Conference Proceedings (OSTI)

Rainfall kinetic energy is a commonly used climatic parameter for the prediction of soil erosion by water. Such a parameter is difficult to measure and is usually estimated from relationships established between rainfall energy and rainfall ...

Colin John Rosewell

1986-11-01T23:59:59.000Z

159

Kinetic measurement and prediction of the hydrogen outgassing from the polycrystalline LiH/Li2O/LiOH system  

DOE Green Energy (OSTI)

Due to the exothermic reaction of lithium hydride (LiH) salt with water during transportation and handling, there is always a thin film of lithium hydroxide (LiOH) present on the LiH surface. In dry or vacuum storage, this thin LiOH film slowly decomposes. We have used temperature-programmed reaction/decomposition (TPR) in combination with the isoconversion method of thermal analysis to determine the outgassing kinetics of H{sub 2}O from pure LiOH and H{sub 2} and H{sub 2}O from this thin LiOH film. H{sub 2} production via the reaction of LiH with LiOH, forming a lithium oxide (Li{sub 2}O) interlayer, is thermodynamically favored, with the rate of further reaction limited by diffusion through the Li{sub 2}O and the stability of the decomposing LiOH. Lithium hydroxide at the LiOH/vacuum interface also decomposes easily to Li{sub 2}O, releasing H{sub 2}O which subsequently reacts with LiH in a closed system to form H{sub 2}. At the onset of dry decomposition, where H{sub 2} is the predominant product, the activation energy for outgassing from a thin LiOH film is lower than that for bulk LiOH. However, as the reactions at the LiH/Li{sub 2}O/LiOH and at the LiOH/vacuum interfaces proceed, the overall activation energy barrier for the outgassing approaches that of bulk LiOH decomposition. The kinetics developed here predicts a hydrogen evolution profile in good agreement with hydrogen release observed during long term isothermal storage.

Dinh, L N; Grant, D M; Schildbach, M A; Smith, R A; Siekhaus, W J; Balazs, B; Leckey, J H; Kirkpatrick, J; McLean II, W

2005-04-06T23:59:59.000Z

160

First measurement of the Head-Tail directional nuclear recoil signature at energies relevant to WIMP dark matter searches  

E-Print Network (OSTI)

We present first evidence for the so-called Head-Tail asymmetry signature of neutron-induced nuclear recoil tracks at energies down to 1.5 keV/amu using the 1m^3 DRIFT-IIc dark matter detector. This regime is appropriate for recoils induced by Weakly Interacting Massive Particle (WIMPs) but one where the differential ionization is poorly understood. We show that the distribution of recoil energies and directions induced here by Cf-252 neutrons matches well that expected from massive WIMPs. The results open a powerful new means of searching for a galactic signature from WIMPs.

S. Burgos; E. Daw; J. Forbes; C. Ghag; M. Gold; C. Hagemann; V. A. Kudryavtsev; T. B. Lawson; D. Loomba; P. Majewski; D. Muna; A. StJ. Murphy; G. G. Nicklin; S. M. Paling; A. Petkov; S. J. S. Plank; M. Robinson; N. Sanghi; D. P. Snowden-Ifft; N. J. C. Spooner; J. Turk; E. Tziaferi

2008-09-10T23:59:59.000Z

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


161

Direct Measurements of Current Shear in the Tropical Pacific Ocean and Its Effect on Drift Buoy Performance  

Science Conference Proceedings (OSTI)

Measurements of ocean surface currents derived from drift buoy trajectories are subject to errors caused by slippage of the buoy relative to the surrounding water. This slippage error is caused by a number of forces acting on the buoy and drogue ...

David S. Bitterman; Donald V. Hansen

1989-04-01T23:59:59.000Z

162

Direct Measurements of Vertical-Velocity Power Spectra with the Sousy-VHF-Radar Wind Profiler System  

Science Conference Proceedings (OSTI)

We present power spectra of vertical velocities measured with the SOUSY-VHF-Radax wind profiler.over a 5-day period in October and November 1981. Most of the data consist of hourly vertical velocity profiles based on 12-rain averages, but, for ...

M. F. Larsen; J. Rutger; D. N. Holden

1987-12-01T23:59:59.000Z

163

Direct measurement of the W boson decay width in proton-antiproton collisions at s**(1/2) = 1.96-TeV  

SciTech Connect

This dissertation describes a direct measurement of the W boson total decay width, {Lambda}{sub W}, using the D0 detector at the Fermilab Tevatron Collider. The measurement uses an integrated luminosity of 177.3 pb{sup -1} data, collected during the 2002-2003 run. The width is determined from the shape of the transverse mass distribution, M{sub T}, by fitting the data in the tail region 100 < M{sub T} < 200 GeV. The result if {Lambda}{sub W} = 2.011 {+-} 0.093(stat) {+-} 0.107(syst) GeV.

Zhu, Jun-jie; /Maryland U.

2004-10-01T23:59:59.000Z

164

Magnetically applied pressure-shear : a new technique for direct strength measurement at high pressure (final report for LDRD project 117856).  

SciTech Connect

A new experimental technique to measure material shear strength at high pressures has been developed for use on magneto-hydrodynamic (MHD) drive pulsed power platforms. By applying an external static magnetic field to the sample region, the MHD drive directly induces a shear stress wave in addition to the usual longitudinal stress wave. Strength is probed by passing this shear wave through a sample material where the transmissible shear stress is limited to the sample strength. The magnitude of the transmitted shear wave is measured via a transverse VISAR system from which the sample strength is determined.

Lamppa, Derek C.; Haill, Thomas A.; Alexander, C. Scott; Asay, James Russell

2010-09-01T23:59:59.000Z

165

On fast reactor kinetics studies  

Science Conference Proceedings (OSTI)

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)

Seleznev, E. F.; Belov, A. A. [Nuclear Safety Inst. of the Russian Academy of Sciences IBRAE (Russian Federation); Matveenko, I. P.; Zhukov, A. M.; Raskach, K. F. [Inst. for Physics and Power Engineering IPPE (Russian Federation)

2012-07-01T23:59:59.000Z

166

In-plane ultrasonic velocity measurement of longitudinal and shear waves in the machine direction with transducers in rotating wheels  

DOE Patents (OSTI)

An improved system for measuring the velocity of ultrasonic signals within the plane of moving web-like materials, such as paper, paperboard and the like. In addition to velocity measurements of ultrasonic signals in the plane of the web in the MD and CD, one embodiment of the system in accordance with the present invention is also adapted to provide on-line indication of the polar specific stiffness of the moving web. In another embodiment of the invention, the velocity of ultrasonic signals in the plane of the web are measured by way of a plurality of ultrasonic transducers carried by synchronously driven wheels or cylinders, thus eliminating undue transducer wear due to any speed differences between the transducers and the web. In order to provide relatively constant contact force between the transducers and the webs, the transducers are mounted in a sensor housings which include a spring for biasing the transducer radially outwardly. The sensor housings are adapted to be easily and conveniently mounted to the carrier to provide a relatively constant contact force between the transducers and the moving web.

Hall, Maclin S. (Marietta, GA); Jackson, Theodore G. (Atlanta, GA); Knerr, Christopher (Lawrenceville, GA)

1998-02-17T23:59:59.000Z

167

In-plane ultrasonic velocity measurement of longitudinal and shear waves in the machine direction with transducers in rotating wheels  

DOE Patents (OSTI)

An improved system for measuring the velocity of ultrasonic signals within the plane of moving web-like materials, such as paper, paperboard and the like. In addition to velocity measurements of ultrasonic signals in the plane of the web in the MD and CD, one embodiment of the system in accordance with the present invention is also adapted to provide on-line indication of the polar specific stiffness of the moving web. In another embodiment of the invention, the velocity of ultrasonic signals in the plane of the web are measured by way of a plurality of ultrasonic transducers carried by synchronously driven wheels or cylinders, thus eliminating undue transducer wear due to any speed differences between the transducers and the web. In order to provide relatively constant contact force between the transducers and the webs, the transducers are mounted in a sensor housings which include a spring for biasing the transducer radially outwardly. The sensor housings are adapted to be easily and conveniently mounted to the carrier to provide a relatively constant contact force between the transducers and the moving web. 37 figs.

Hall, M.S.; Jackson, T.G.; Knerr, C.

1998-02-17T23:59:59.000Z

168

The Thermodynamics and Kinetics of Dissolution of Coarse Particles ...  

Science Conference Proceedings (OSTI)

A model of the kinetics of dissolution of Nb-rich and Nb2C particles in .... The Influence of Specimen Fabrication Method on the Measured Tensile ...

169

Chemical Dynamics, Molecular Energetics, and Kinetics at the Synchrotron  

E-Print Network (OSTI)

novel measurements of chemical dynamics for clusters, Chemical Dynamics, Molecular Energetics, and Kinetics at theUniversity of California Chemical Sciences Division,

Leone, Stephen R.

2010-01-01T23:59:59.000Z

170

First Direct Double- Decay Q-Value Measurement of 82Se in Support of Understanding the Nature of the Neutrino  

Science Conference Proceedings (OSTI)

In anticipation of results from current and future double- decay studies, we report a measurement resulting in a 82Se double- decay Q value of 2997.9(3) keV, an order of magnitude more precise than the currently accepted value. We also present preliminary results of a calculation of the 82Se neutrinoless double- decay nuclear matrix element that corrects in part for the small size of the shell model single-particle space. The results of this work are important for designing next generation double- decay experiments and for the theoretical interpretations of their observations.

Lincoln, David L. [NSCL, Michigan State University, East Lansing; Holt, Jason D. [Technische Univ. Darmstadt/GSI/UTK/ORNL; Bollen, Georg [NSCL, Michigan State University, East Lansing; Brodeur, Maxime [NSCL, Michigan State University, East Lansing; Bustabad, Scott [NSCL, Michigan State University, East Lansing; Engel, Jonathan [University of North Carolina, Chapel Hill; Novario, Samuel J. [NSCL, Michigan State University, East Lansing; Redshaw, Matthew [NSCL, Michigan State Univ.,/Central Michigan Univ.-Mt. Pleasant; Ringle, Ryan [NSCL, Michigan State University, East Lansing; Schwarz, Stefan [NSCL, Michigan State University, East Lansing

2013-01-01T23:59:59.000Z

171

Direct measurement of the spin gaps in a gated GaAs two-dimensional electron gas  

E-Print Network (OSTI)

. For the low-field regime where ?s destroyed by the disorder, and there is no spin-splitting for the magnetic field less than Bc. As shown in Figure 7, the ‘spin gap’ measured by the conventional activation energy studies... linearly to zero at a critical magnetic field Bc ~ 3.47 T. The spin gap is expected to have the form ?s = g0?BB + Eex = g * ?BB [12], where Eex is the many-body exchange energy which lifts the g-factor from its bare value (0.44 in GaAs) to its enhanced...

Huang, Tsai-Yu; Liang, Chi-Te; Chen, Yang Fang; Simmons, Michelle Y; Kim, Gil-Ho; Ritchie, David A

2013-03-25T23:59:59.000Z

172

Computational Thermodynamics and Kinetics  

Science Conference Proceedings (OSTI)

A Comprehensive Investigation of Low Angle Grain Boundary Mobility in Pure Al ... A New Treatment for the Kinetics of Isothermal Oxidation of Zinc Powders.

173

Structure and Kinetics  

Science Conference Proceedings (OSTI)

Mar 4, 2013 ... Materials Science in Reduced Gravity: Structure and Kinetics ... Bias fields comprise weak interface energy sources that result from the vector ...

174

A Method for Estimating the Turbulent Kinetic Energy Dissipation Rate from a Vertically Pointing Doppler Lidar, and Independent Evaluation from Balloon-Borne In Situ Measurements  

Science Conference Proceedings (OSTI)

A method of estimating dissipation rates from a vertically pointing Doppler lidar with high temporal and spatial resolution has been evaluated by comparison with independent measurements derived from a balloon-borne sonic anemometer. This method ...

Ewan J. O’Connor; Anthony J. Illingworth; Ian M. Brooks; Christopher D. Westbrook; Robin J. Hogan; Fay Davies; Barbara J. Brooks

2010-10-01T23:59:59.000Z

175

Measurement of critical energy for direct initiation of spherical detonations in stoichiometric high-pressure H{sub 2}-O{sub 2} mixtures  

SciTech Connect

In this study, the critical energy for direct initiation of spherical detonations in stoichiometric high-pressure hydrogen-oxygen mixtures are measured and investigated to look at the effect of explosion limits on the detonation sensitivity. Results up to an initial pressure of 20 atm are obtained. Experiments are carried out in a spherical bomb and direct initiation is achieved via spark ignition from a high-voltage capacitor discharge. A detailed description of different methods to obtain a good estimate of the correct amount of energy deposited into the mixture used to initiate the detonation, including the calorimeter method and current method, is provided. It is demonstrated that at elevated initial pressure, the second explosion limit effect plays a significant role leading to slow-branching reactions and the detonation sensitivity of hydrogen mixtures is comparable to other common hydrocarbon mixtures at such condition. (author)

Kamenskihs, Vsevolods; Lee, John H.S. [Department of Mechanical Engineering, McGill University, Montreal, Quebec (Canada); Ng, Hoi Dick [Department of Mechanical and Industrial Engineering, Concordia University, Montreal, Quebec (Canada)

2010-09-15T23:59:59.000Z

176

Heat transfer and pressure drop measurements in an air/molten salt direct-contact heat exchanger  

SciTech Connect

This paper presents a comparison of experimental data with a recently published model of heat exchange in irrigated packed beds. Heat transfer and pressure drop were measured in a 150 mm (ID) column with a 610-mm bed of metal Pall rings. Molten nitrate salt and preheated air were the working fluids with a salt inlet temperature of approximately 440{degree}C and air inlet temperatures of approximately 230{degree}C. A comparison between the experimental data and the heat transfer model is made on the basis of heat transfer from the salt. For the range of air and salt flow rates tested, 0.3 to 1.2 kg/m{sup 2} s air flow and 6 to 18 kg/m{sup 2} s salt flow, the data agree with the model within 22% standard deviation. In addition, a model for the column pressure drop was validated, agreeing with the experimental data within 18% standard deviation over the range of column pressure drop from 40 to 1250 Pa/m. 25 refs., 7 figs., 2 tabs.

Bohn, M.S.

1988-11-01T23:59:59.000Z

177

Direct Measurement of Initial Enrichment and Burn-up of Spent Fuel Assembly with a Differential Die-Away Technique Based Instrument  

SciTech Connect

A key objective of the Next Generation Safeguards Initiative (NGSI) is to utilize non-destructive assay (NDA) techniques to determine the elemental plutonium (Pu) content in a commercial-grade nuclear spent fuel assembly (SFA). In the third year of the NGSI Spent Fuel NDA project, the research focus is on the integration of a few NDA techniques. One of the reoccurring challenges to the accurate determination of Pu content has been the explicit dependence of the measured signal on the presence of neutron absorbers which build up in the assembly in accordance with its operating and irradiation history. The history of any SFA is often summarized by the parameters of burn-up (BU), initial enrichment (IE) and cooling time (CT). While such parameters can typically be provided by the operator, the ability to directly measure and verify them would significantly enhance the autonomy of the IAEA inspectorate. Within this paper, we demonstrate that an instrument based on a Differential Die-Away technique is in principle capable of direct measurement of IE and, should the CT be known, also the BU.

Henzl, Vladimir [Los Alamos National Laboratory; Swinhoe, Martyn T. [Los Alamos National Laboratory; Tobin, Stephen J. [Los Alamos National Laboratory

2012-07-16T23:59:59.000Z

178

Kinetic Modeling of Microbiological Processes  

Science Conference Proceedings (OSTI)

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.

Liu, Chongxuan; Fang, Yilin

2012-09-17T23:59:59.000Z

179

Development of a chemical kinetic measurement apparatus and the determination of the reaction rate constants for lithium-lead/water interactions. Progress report, October 1990--September 1991  

DOE Green Energy (OSTI)

An experimental set-up for accurate measurement of hydrogen generation rate in Lithium-Lead (Li{sub 17}Pb{sub 83}) Steam or water interactions is being designed. The most important features of the design include a pneumatic actuated quick opening and closing butterfly valve used to control the reaction time and the placement of all measuring devices below a water line to minimize leakage of the hydrogen collected. A PC based data acquisition and control system provides remote process sequencing, acquisition and control of all major components of the set-up.

Biney, P.O.

1991-11-01T23:59:59.000Z

180

Development of a chemical kinetic measurement apparatus and the determination of the reaction rate constants for lithium-lead/water interactions  

DOE Green Energy (OSTI)

An experimental set-up for accurate measurement of hydrogen generation rate in Lithium-Lead (Li{sub 17}Pb{sub 83}) Steam or water interactions is being designed. The most important features of the design include a pneumatic actuated quick opening and closing butterfly valve used to control the reaction time and the placement of all measuring devices below a water line to minimize leakage of the hydrogen collected. A PC based data acquisition and control system provides remote process sequencing, acquisition and control of all major components of the set-up.

Biney, P.O.

1991-11-01T23:59:59.000Z

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We encourage you to perform a real-time search of NLEBeta
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181

Measurement of the Low Energy Nuclear Response in NaI(Tl) Crystals for Use in Dark Matter Direct Detection Experiments  

E-Print Network (OSTI)

The response of low energy nuclear recoil in NaI(Tl) is investigated in the following experiment. Such detectors have been used recently to search for evidence of dark matter in the form of weakly interacting massive particles (WIMPs). NaI(Tl) crystal response to nuclear recoil energy deposition is a key element in these searches. I discuss the cosmological and experimental motivations for these experiments, followed by an overview of the physics of direct detection and current relevant WIMP search experiments. With the experiment motivations covered, the details of NaI(Tl) detectors are reviewed. The specifics of our experiment are laid out including the neutron production, neutron beam calibration, shielding optimization, experimental design and setup. Then the crystal response calibration studies and Geant4 simulations are discussed followed by the final quenching factor values and uncertainties. This experiment measured quenching factors for sodium recoils in the energy range of (9 keV-40 keV) of 19%-27% QF. These results are similar to current published measurements. Interesting features of the QF measurements include an increase at low energies and a dip in the values at 30 keV, the iodine K-shell absorption edge. The goal of this experiment was to add valuable measurements of nuclear recoils at low energies that are relevant to low-mass WIMP experiments. Future plans will improve and expand on these measurements in order to better understand the response of NaI(Tl) at low energies.

Stiegler, Tyana Michele

2013-08-01T23:59:59.000Z

182

Direct Photons at RHIC  

E-Print Network (OSTI)

Abstract. The PHENIX experiment has measured direct photons in ? sNN = 200 GeV Au+Au collisions and p+p collisions. The fraction of photons due to direct

Saskia Mioduszewski; Phenix Collaboration

2004-01-01T23:59:59.000Z

183

Thermodynamic and Kinetic Modeling  

Science Conference Proceedings (OSTI)

Oct 11, 2012... capability of the coating and thus the achievable engine efficiency. ... Aluminide coating of steels enables more efficient power generation through ... and kinetic modeling in order to build a time and temperature dependent ...

184

Higher-order quadrature-based moment methods for kinetic equations  

Science Conference Proceedings (OSTI)

Kinetic equations containing terms for spatial transport, body forces, and particle-particle collisions occur in many applications (e.g., rarefied gases, dilute granular gases, fluid-particle flows). The direct numerical solution of the kinetic equation ... Keywords: Boltzmann equation, Dilute particle flows, Kinetic equation, Quadrature method of moments, Rarefied gas flows, Velocity distribution function

R. O. Fox

2009-11-01T23:59:59.000Z

185

Thermodynamic & Kinetic Data for Sustainable Energy  

Science Conference Proceedings (OSTI)

Thermodynamic & Kinetic Data for Sustainable Energy. Summary: Industry needs thermodynamic and kinetic data for the ...

2012-10-05T23:59:59.000Z

186

A direct measurement of rotatable and frozen CoO spins in exchange bias system of CoO/Fe/Ag(001)  

SciTech Connect

The exchange bias of epitaxially grown CoO/Fe/Ag(001) was investigated using x-ray magnetic circular dichroism and x-ray magnetic linear dichroism (XMLD) techniques. A direct XMLD measurement on the CoO layer during the Fe magnetization reversal shows that the CoO compensated spins are rotatable at thinner thickness and frozen at larger thickness. By a quantitative determination of the rotatable and frozen CoO spins as a function of the CoO film thickness, we find the remarkable result that the exchange bias is well established before frozen spins are detectable in the CoO film. We further show that the rotatable and frozen CoO spins are uniformly distributed in the CoO film.

Wu, J.; Park, J. S.; Kim, W.; Arenholz, E.; Liberati, M.; Scholl, A.; Wu, Y. Z.; Hwang, C.; Qiu, Z. Q.

2010-03-10T23:59:59.000Z

187

JGI - Directions  

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

Map to JGI Directions from Directions from key local start points, public transit Home > About Us > Map to JGI UC logo DOE logo Contact Us Credits Disclaimer Access...

188

Evidence for Direct CP Violation in the Measurement of the Cabibbo-Kobayashi-Maskawa Angle gamma with B-+ to D(*) K(*)-+ Decays  

SciTech Connect

We report the measurement of the Cabibbo-Kobayashi-Maskawa CP-violating angle {gamma} through a Dalitz plot analysis of neutral D meson decays to K{sub S}{sup 0}{pi}{sup +}{pi}{sup -} and K{sub S}{sup 0} K{sup +}K{sup -} produced in the processes B{sup {-+}} {yields} DK{sup {-+}}, B{sup {-+}} {yields} D* K{sup {-+}} with D* {yields} D{pi}{sup 0}, D{gamma}, and B{sup {-+}} {yields} DK*{sup {-+}} with K*{sup {-+}} {yields} K{sub S}{sup 0}{pi}{sup {-+}}, using 468 million B{bar B} pairs collected by the BABAR detector at the PEP-II asymmetric-energy e{sup +}e{sup -} collider at SLAC. We measure {gamma} = (68 {+-} 14 {+-} 4 {+-} 3){sup o} (modulo 180{sup o}), where the first error is statistical, the second is the experimental systematic uncertainty and the third reflects the uncertainty in the description of the neutral D decay amplitudes. This result is inconsistent with {gamma} = 0 (no direct CP violation) with a significance of 3.5 standard deviations.

del Amo Sanchez, P.; Lees, J.P.; Poireau, V.; Prencipe, E.; Tisserand, V.; /Annecy, LAPP; Garra Tico, J.; Grauges, E.; /Barcelona U., ECM; Martinelli, M.; Palano, A.; Pappagallo, M.; /INFN, Bari /Bari U.; Eigen, G.; Stugu, B.; Sun, L.; /Bergen U.; Battaglia, M.; Brown, D.N.; Hooberman, B.; Kerth, L.T.; Kolomensky, Yu.G.; Lynch, G.; Osipenkov, I.L.; Tanabe, T.; /UC, Berkeley /Birmingham U. /Ruhr U., Bochum /British Columbia U. /Brunel U. /Novosibirsk, IYF /UC, Irvine /UC, Riverside /UC, Santa Barbara /UC, Santa Cruz /Caltech /Cincinnati U. /Colorado U. /Colorado State U. /Dortmund U. /Dresden, Tech. U. /Ecole Polytechnique /Edinburgh U. /INFN, Ferrara /Ferrara U. /INFN, Ferrara /INFN, Ferrara /Ferrara U. /INFN, Ferrara /Frascati /INFN, Genoa /Genoa U. /INFN, Genoa /INFN, Genoa /Genoa U. /INFN, Genoa /INFN, Genoa /Genoa U. /Indian Inst. Tech., Guwahati /Harvard U. /Heidelberg U. /Humboldt U., Berlin /Imperial Coll., London /Iowa State U. /Iowa State U. /Johns Hopkins U. /Orsay, LAL /LLNL, Livermore /Liverpool U. /Queen Mary, U. of London /Royal Holloway, U. of London /Louisville U. /Mainz U., Inst. Kernphys. /Manchester U. /Maryland U. /Massachusetts U., Amherst /MIT /McGill U. /INFN, Milan /Milan U. /INFN, Milan /INFN, Milan /Milan U. /Mississippi U. /Montreal U. /INFN, Naples /Naples U. /NIKHEF, Amsterdam /Notre Dame U. /Ohio State U. /Oregon U. /INFN, Padua /Padua U. /INFN, Padua /INFN, Padua /Padua U. /Paris U., VI-VII /INFN, Perugia /Perugia U. /INFN, Pisa /Pisa U. /INFN, Pisa /Pisa, Scuola Normale Superiore /INFN, Pisa /Pisa U. /INFN, Pisa /Princeton U. /INFN, Rome /INFN, Rome /Rome U. /INFN, Rome /INFN, Rome /Rome U. /INFN, Rome /INFN, Rome /Rome U. /INFN, Rome /INFN, Rome /Rome U. /Rostock U. /Rutherford /DAPNIA, Saclay /SLAC /South Carolina U. /Southern Methodist U. /Stanford U., Phys. Dept. /SUNY, Albany /Tel Aviv U. /Tennessee U. /Texas U. /Texas U., Dallas /INFN, Turin /Turin U. /INFN, Trieste /Trieste U. /Valencia U. /Victoria U. /Warwick U. /Wisconsin U., Madison

2011-08-19T23:59:59.000Z

189

Measurements of branching fractions, polarizations, and direct CP-violation asymmetries in B -> rho0 K* and B -> f0(980) K* decays  

SciTech Connect

We present measurements of the branching fractions, longitudinal polarization, and direct CP-violation asymmetries for the decays B{sup +} {yields} {rho}{sup 0}K*{sup +} and B{sup +} f{sub 0}(980)K*{sup +} with a sample of (467 {+-} 5) x 10{sup 6} B{bar B} pairs collected with the BABAR detector at the PEP-II asymmetric-energy e{sup +}e{sup -} collider at the SLAC National Accelerator Laboratory. We observe B{sup +} {yields} {rho}{sup 0}K*{sup +} with a significance of 5.3{sigma} and measure the branching fraction {Beta}(B{sup +} {yields} {rho}{sup 0}K*{sup +}) = (4.6 {+-} 1.0 {+-} 0.4) x 10{sup -6}, the longitudinal polarization f{sub L} = 0.78 {+-} 0.12 {+-} 0.03, and the CP-violation asymmetry A{sub CP} = 0.31 {+-} 0.13 {+-} 0.03. We observe B{sup +} {yields} f{sub 0}(980)K*{sup +} and measure the branching fraction {Beta}(B{sup +} {yields} f{sub 0}(980)K*{sup +}) x {Beta}(f{sub 0}(980) {yields} {pi}{sup +}{pi}{sup -}) = (4.2 {+-} 0.6 {+-} 0.3) x 10{sup -6} and the CP-violation asymmetry A{sub CP} = -0.15 {+-} 0.12 {+-} 0.03. The first uncertainty quoted is statistical and the second is systematic.

del Amo Sanchez, P.; Lees, J.P.; Poireau, V.; Prencipe, E.; Tisserand, V.; /Annecy, LAPP; Garra Tico, J.; Grauges, E.; /Barcelona U., ECM; Martinelli, M.; /INFN, Bari /Bari U.; Milanes, D.A.; /INFN, Bari; Palano, A.; Pappagallo, M.; /INFN, Bari /Bari U.; Eigen, G.; Stugu, B.; Sun, L.; /Bergen U.; Brown, D.N.; Kerth, L.T.; Kolomensky, Yu.G.; Lynch, G.; Osipenkov, I.L.; /UC, Berkeley; Koch, H.; Schroeder, T.; /Ruhr U., Bochum /British Columbia U. /Brunel U. /Novosibirsk, IYF /UC, Irvine /UC, Riverside /UC, Santa Barbara /UC, Santa Cruz /Caltech /Cincinnati U. /Colorado U. /Colorado State U. /Dortmund U. /Dresden, Tech. U. /Ecole Polytechnique /Edinburgh U. /INFN, Ferrara /Ferrara U. /INFN, Ferrara /INFN, Ferrara /Ferrara U. /INFN, Ferrara /Frascati /INFN, Genoa /Genoa U. /INFN, Genoa /INFN, Genoa /Genoa U. /INFN, Genoa /INFN, Genoa /Genoa U. /Indian Inst. Tech., Guwahati /Harvard U. /Harvey Mudd Coll. /Heidelberg U. /Humboldt U., Berlin /Imperial Coll., London /Iowa State U. /Iowa State U. /Johns Hopkins U. /Orsay, LAL /LLNL, Livermore /Liverpool U. /Queen Mary, U. of London /Royal Holloway, U. of London /Louisville U. /Mainz U., Inst. Kernphys. /Manchester U. /Maryland U. /Massachusetts U., Amherst /MIT /McGill U. /INFN, Milan /Milan U. /INFN, Milan /INFN, Milan /Milan U. /Mississippi U. /Montreal U. /INFN, Naples /Naples U. /NIKHEF, Amsterdam /NIKHEF, Amsterdam /Notre Dame U. /Ohio State U. /Oregon U. /INFN, Padua /Padua U. /INFN, Padua /INFN, Padua /Padua U. /Paris U., VI-VII /INFN, Perugia /Perugia U. /INFN, Pisa /Pisa U. /INFN, Pisa /Pisa, Scuola Normale Superiore /INFN, Pisa /Pisa U. /INFN, Pisa /Princeton U. /INFN, Rome /INFN, Rome /Rome U. /INFN, Rome /INFN, Rome /Rome U. /INFN, Rome /INFN, Rome /Rome U. /INFN, Rome /INFN, Rome /Rome U. /Rostock U. /Rutherford /DAPNIA, Saclay /SLAC /South Carolina U. /Southern Methodist U. /Stanford U., Phys. Dept. /SUNY, Albany /Tel Aviv U. /Tennessee U. /Texas Nuclear Corp., Austin /Texas U., Dallas /INFN, Turin /Turin U. /INFN, Trieste /Trieste U. /Valencia U. /Victoria U. /Warwick U. /Wisconsin U., Madison

2011-08-12T23:59:59.000Z

190

Direct Photons at RHIC  

E-Print Network (OSTI)

The PHENIX experiment has measured direct photons in $\\sqrt{s_{NN}} = 200$ GeV Au+Au collisions and p+p collisions. The fraction of photons due to direct production in Au+Au collisions is shown as a function of $p_T$ and centrality. This measurement is compared with expectation from pQCD calculations. Other possible sources of direct photons are discussed.

S. Mioduszewski; for the PHENIX Collaboration

2004-09-29T23:59:59.000Z

191

Erbium hydride decomposition kinetics.  

DOE Green Energy (OSTI)

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.

Ferrizz, Robert Matthew

2006-11-01T23:59:59.000Z

192

Note: Direct measurement of the point-to-point resolution for microns-thick specimens in the ultrahigh-voltage electron microscope  

SciTech Connect

We report on a direct measurement method and results of the point-to-point resolution for microns-thick amorphous specimens in the ultrahigh-voltage electron microscope (ultra-HVEM). We first obtain the ultra-HVEM images of nanometer gold particles with different sizes on the top surfaces of the thick epoxy-resin specimens. Based on the Rayleigh criterion, the point-to-point resolution is then determined as the minimum distance between centers of two resolvable tangent gold particles. Some values of resolution are accordingly acquired for the specimens with different thicknesses at the accelerating voltage of 2 MV, for example, 18.5 nm and 28.4 nm for the 5 {mu}m and 8 {mu}m thick epoxy-resin specimens, respectively. The presented method and results provide a reliable and useful approach to quantifying and comparing the achievable spatial resolution for the thick specimens imaged in the mode of transmission electron including the scanning transmission electron microscope.

Wang Fang; Cao Meng; Zhang Haibo [Key Laboratory for Physical Electronics and Devices of the Ministry of Education, Department of Electronic Science and Technology, Xi'an Jiaotong University, Xi'an 710049 (China); Nishi, Ryuji; Takaoka, Akio [Research Center for Ultrahigh-Voltage Electron Microscopy, Osaka University, 7-1 Mihogaoka, Ibaraki, Osaka 567-0047 (Japan)

2011-06-15T23:59:59.000Z

193

A Novel Approach to Experimental Studies of Mineral DIsoolution Kinetics  

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

Novel ApproAch to experimeNtAl Novel ApproAch to experimeNtAl StudieS of miNerAl diSSolutioN KiNeticS Background DOE is conducting pilot CO 2 injection tests to evaluate the concept of geologic sequestration. One strategy that has the potential to enhance CO 2 solubility and reduce the risk of CO 2 leaking back to the surface is dissolution of indigenous minerals in the geological formation and formation of secondary carbonate precipitates. This both increases the brine pH and immobilizes the CO 2 . Clearly, the rates at which these dissolution and precipitation reactions occur directly determine the efficiency of this option. However, one of the fundamental problems in modern geochemistry is the persistent two to five orders of magnitude discrepancy between laboratory-measured and field-derived

194

Direct Photons at RHIC  

E-Print Network (OSTI)

A brief overview of direct-photon measurements in p+p and Au+Au collisions at sqrt(s_NN) = 200 GeV with the PHENIX experiment at the Relativistic Heavy Ion Collider (RHIC) is given. Direct-photon yields for pT > 4 GeV/c and photon-hadron azimuthal correlations were determined with the aid of an electromagnetic calorimeter. By detecting e+e- pairs from the internal conversion of virtual photons direct-photon yields were measured between 1 direct-photon yield in this range.

Klaus Reygers; for the PHENIX Collaboration

2009-08-17T23:59:59.000Z

195

Kinetic Theory of Plasma Waves  

Science Conference Proceedings (OSTI)

Kinetic Wave Theory / Proceedings of the Tenth Carolus Magnus Summer School on Plasma and Fusion Energy Physics

D. Van Eester; E. Lerche

196

LLNL Chemical Kinetics Modeling Group  

DOE Green Energy (OSTI)

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.

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

2008-09-24T23:59:59.000Z

197

CONSERVATIVE CASCADE OF KINETIC ENERGY IN COMPRESSIBLE TURBULENCE  

SciTech Connect

The physical nature of compressible turbulence is of fundamental importance in a variety of astrophysical settings. We investigate the question: 'At what scales does the mechanism of pressure-dilatation operate?' and present the first direct evidence that mean kinetic energy cascades conservatively beyond a transitional 'conversion' scale range despite not being an invariant of the dynamics. We use high-resolution 1024{sup 3} subsonic and transonic simulations. The key quantity we measure is the pressure-dilatation cospectrum, E{sup PD}(k), where we show that it decays at a rate faster than k{sup -1} in wavenumber in at least the subsonic and transonic regimes. This is sufficient to imply that mean pressure-dilatation acts primarily at large scales and that kinetic and internal energy budgets statistically decouple beyond a transitional scale range. However, we observe that small-scale dynamics remains highly compressible locally in space and that the statistical decoupling in the energy budgets is unrelated to the existence of a subsonic scale range. Our results suggest that an extension of Kolmogorov's inertial-range theory to compressible turbulence is possible.

Aluie, Hussein; Li Shengtai; Li, Hui [Los Alamos National Laboratory, Los Alamos, NM 87545 (United States)

2012-06-01T23:59:59.000Z

198

The conservative cascade of kinetic energy in compressible turbulence  

E-Print Network (OSTI)

The physical nature of compressible turbulence is of fundamental importance in a variety of astrophysical settings. We present the first direct evidence that mean kinetic energy cascades conservatively beyond a transitional "conversion" scale-range despite not being an invariant of the compressible flow dynamics. We use high-resolution three-dimensional simulations of compressible hydrodynamic turbulence on $512^3$ and $1024^3$ grids. We probe regimes of forced steady-state isothermal flows and of unforced decaying ideal gas flows. The key quantity we measure is pressure dilatation cospectrum, $E^{PD}(k)$, where we provide the first numerical evidence that it decays at a rate faster than $k^{-1}$ as a function of wavenumber. This is sufficient to imply that mean pressure dilatation acts primarily at large-scales and that kinetic and internal energy budgets statistically decouple beyond a transitional scale-range. Our results suggest that an extension of Kolmogorov's inertial-range theory to compressible turbulence is possible.

Hussein Aluie; Shengtai Li; Hui Li

2011-07-28T23:59:59.000Z

199

The conservative cascade of kinetic energy in compressible turbulence  

E-Print Network (OSTI)

The physical nature of compressible turbulence is of fundamental importance in a variety of astrophysical settings. We present the first direct evidence that mean kinetic energy cascades conservatively beyond a transitional "conversion" scale-range despite not being an invariant of the compressible flow dynamics. We use high-resolution three-dimensional simulations of compressible hydrodynamic turbulence on $512^3$ and $1024^3$ grids. We probe regimes of forced steady-state isothermal flows and of unforced decaying ideal gas flows. The key quantity we measure is pressure dilatation cospectrum, $E^{PD}(k)$, where we provide the first numerical evidence that it decays at a rate faster than $k^{-1}$ as a function of wavenumber. This is sufficient to imply that mean pressure dilatation acts primarily at large-scales and that kinetic and internal energy budgets statistically decouple beyond a transitional scale-range. Our results suggest that an extension of Kolmogorov's inertial-range theory to compressible turbu...

Aluie, Hussein; Li, Hui

2011-01-01T23:59:59.000Z

200

Kinetic equilibrium and relativistic thermodynamics  

E-Print Network (OSTI)

Relativistic thermodynamics is treated from the point of view of kinetic theory. It is shown that the generalized J\\"uttner distribution suggested in [1] is compatible with kinetic equilibrium. The requirement of compatibility of kinetic and thermodynamic equilibrium reveals several generalizations of the Gibbs relation where the velocity field is an independent thermodynamic variable.

Ván, P

2011-01-01T23:59:59.000Z

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


201

Kinetic equilibrium and relativistic thermodynamics  

E-Print Network (OSTI)

Relativistic thermodynamics is treated from the point of view of kinetic theory. It is shown that the generalized J\\"uttner distribution suggested in [1] is compatible with kinetic equilibrium. The requirement of compatibility of kinetic and thermodynamic equilibrium reveals several generalizations of the Gibbs relation where the velocity field is an independent thermodynamic variable.

P. Ván

2011-02-01T23:59:59.000Z

202

Direct mechanical energy measures of hammer mill comminution of switchgrass, wheat straw, and corn stover and analysis of their particle size distributions  

Science Conference Proceedings (OSTI)

Biomass particle size impacts handling, storage, conversion, and dust control systems. Size reduction mechanical energy was directly measured for switchgrass (Panicum virgatum L.), wheat straw (Triticum aestivum L.), and corn stover (Zea mays L.) in an instrumented hammer mill. Direct energy inputs were determined for hammer mill operating speeds from 2000 to 3600 rpm for 3.2 mm integral classifying screen and mass input rate of 2.5 kg/min with 90 - and 30 -hammers. Overall accuracy of specific energy measurement was calculated as 0.072 MJ/Mg. Particle size distributions created by hammer mill were determined for mill operating factors using ISO sieve sizes from 4.75 to 0.02 mm in conjunction with Ro-Tap sieve analyzer. A wide range of analytical descriptors were examined to mathematically represent the range of particle sizes in the distributions. Total specific energy (MJ/Mg) was defined as size reduction energy to operate the hammer mill plus that imparted to biomass. Effective specific energy was defined as energy imparted to biomass. Total specific energy for switchgrass, wheat straw, and corn stover grinding increased by 37, 30, and 45% from 114.4, 125.1, and 103.7 MJ/Mg, respectively, with an increase in hammer mill speed from 2000 to 3600 rpm for 90 -hammers. Corresponding total specific energy per unit size reduction was 14.9, 19.7, and 13.5 MJ/Mg mm, respectively. Effective specific energy of 90 -hammers decreased marginally for switchgrass and considerably for wheat straw and it increased for corn stover with an increase in speed from 2000 to 3600 rpm. However, effective specific energy increased with speed to a certain extent and then decreased for 30 -hammers. Rosin Rammler equation fitted the size distribution data with R2 > 0.995. Mass relative span was greater than 1, which indicated a wide distribution of particle sizes. Hammer milling of switchgrass, wheat straw, and corn stover with 3.2 mm screen resulted in well-graded fine-skewed mesokurtic particles. Uniformity coefficient was corn stover, which indicated a moderate assortment of particles. Size-related parameters, namely, geometric mean diameter, Rosin Rammler size parameter, median diameter, and effective size had strong correlation among themselves and good negative correlation with speed. Distribution-related parameters, namely, Rosin Rammler distribution parameter, mass relative span, inclusive graphic skewness, graphic kurtosis, uniformity index, uniformity coefficient, coefficient of gradation and distribution geometric standard deviation had strong correlation among themselves and a weak correlation with mill speed. Results of this extensive analysis of specific energy and particle sizes can be applied to selection of hammer mill operating factors to produce a particular size of switchgrass, wheat straw, and corn stover grind, and will serve as a guide for relations among the energy and various analytic descriptors of biomass particle distributions.

Bitra, V.S.P [University of Tennessee; Womac, A.R. [University of Tennessee; Chevanan, Nehru [University of Tennessee; Miu, P.I. [University of Tennessee; Smith, D.R. [University of Tennessee; Igathinathane, C. [Mississippi State University (MSU); Sokhansanj, Shahabaddine [ORNL

2009-07-01T23:59:59.000Z

203

The Track Integrated Kinetic Energy of Atlantic Tropical Cyclones  

Science Conference Proceedings (OSTI)

In this paper the concept of track integrated kinetic energy (TIKE) is introduced as a measure of seasonal Atlantic tropical cyclone activity and applied to seasonal variability in the Atlantic. It is similar in concept to the more commonly used ...

V. Misra; S. DiNapoli; M. Powell

2013-07-01T23:59:59.000Z

204

Kinetic electrocaloric effect and giant net cooling of lead-free ferroelectric refrigerants  

SciTech Connect

The electrocaloric effect of BaTiO{sub 3} multilayer thick film structure was investigated by direct measurement using differential scanning calorimeter. The samples show a giant electrocaloric effect of 0.89 J/g under E=176 kV/cm, which also depends on the varying rate of applied field, following a general power-law relation. Based on the large net-cooling (0.37 J/g) resulting from the difference in the varying rates of rising and falling fields, the kinetic electrocaloric effect provides a solution for the design of refrigeration cycle in ferroelectric microrefrigerator.

Bai Yang [Department of Mechanical Engineering, Hong Kong Polytechnic University, Hung Hom, Kowloon (Hong Kong); Key Laboratory of Environmental Fracture, University of Science and Technology Beijing, Ministry of Education, Beijing 100083 (China); Zheng Guangping; Shi Sanqiang [Department of Mechanical Engineering, Hong Kong Polytechnic University, Hung Hom, Kowloon (Hong Kong)

2010-11-15T23:59:59.000Z

205

JGI - Directions  

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

Directions Address DOE Joint Genome Institute 2800 Mitchell Drive Walnut Creek, CA 94598 From Oakland Airport Follow Airport exit signs onto AIRPORT DR. Turn RIGHT onto HEGENBERGER...

206

Experimental Characterization of a Direct Carbon Solid Oxide Fuel ...  

Science Conference Proceedings (OSTI)

To more rationally guide the design of liquid tin anode SOFCs, research at NETL has focused on measuring the kinetic parameters of the liquid tin anode under ...

207

Our purpose and direction Our purpose and direction  

E-Print Network (OSTI)

1 Our purpose and direction #12;Our purpose and direction Contents MINISTERS' FOREWORD 3 8 Our People 8 Our finances 8 Business sustainability ­ `Greenerways' 9 OUR DIRECTION 10 Our Appendix 2: Business measures 55 Appendix 3: Financial resources 56 2 #12;3 Our purpose and direction

208

Ducted kinetic Alfven waves in plasma with steep density gradients  

SciTech Connect

Given their high plasma density (n {approx} 10{sup 13} cm{sup -3}), it is theoretically possible to excite Alfven waves in a conventional, moderate length (L {approx} 2 m) helicon plasma source. However, helicon plasmas are decidedly inhomogeneous, having a steep radial density gradient, and typically have a significant background neutral pressure. The inhomogeneity introduces regions of kinetic and inertial Alfven wave propagation. Ion-neutral and electron-neutral collisions alter the Alfven wave dispersion characteristics. Here, we present the measurements of propagating kinetic Alfven waves in helium helicon plasma. The measured wave dispersion is well fit with a kinetic model that includes the effects of ion-neutral damping and that assumes the high density plasma core defines the radial extent of the wave propagation region. The measured wave amplitude versus plasma radius is consistent with the pile up of wave magnetic energy at the boundary between the kinetic and inertial regime regions.

Houshmandyar, Saeid [Solar Observatory Department, Prairie View A and M University, Prairie View, Texas 77446 (United States); Department of Physics, West Virginia University, Morgantown, West Virginia 26506-6315 (United States); Scime, Earl E. [Department of Physics, West Virginia University, Morgantown, West Virginia 26506-6315 (United States)

2011-11-15T23:59:59.000Z

209

SHORT CONTACT TIME DIRECT COAL LIQUEFACTION USING A NOVEL BATCH REACTOR  

DOE Green Energy (OSTI)

The overall goal of this research is to develop an understanding of the Direct Coal Liquefaction process at the molecular level. Many approaches have been used to study this process including kinetic studies, study of the liquefaction products, study of the effect of reaction variables, such as temperature, solvent type and composition, the changing nature and composition of the coal during liquefaction, and the distribution in the liquefaction products of the hydrogen consumed. While all these studies have contributed to our growing knowledge of the liquefaction process, an adequate understanding of direct liquefaction still eludes us. This is due to many reasons including: the complexity and variable nature of coal itself and the many different chemical reactions which are occurring simultaneously during direct coal liquefaction. We believe that a study of the liquefaction process at the very early stages will avoid the complexities of secondary reactions associated with free radical high temperature processes that are clearly involved in direct coal liquefaction. This prompted us to devise a reactor system which avoids long heat up and cool-down times associated with previous kinetic studies, and allows kinetic measurements even at as short as the first few seconds of the liquefaction reaction.

Michael T. Klein; William H. Calkins

1997-10-29T23:59:59.000Z

210

Measurement of the Cross Section for Direct-Photon Production in Association with a Heavy Quark in p[¯ over p] Collisions at ?s=1.96??TeV  

E-Print Network (OSTI)

We report on a measurement of the cross section for direct-photon production in association with a heavy quark using the full data set of ?s=1.96??TeV proton-antiproton collisions corresponding to 9.1??fb[superscript -1] ...

Gomez-Ceballos, Guillelmo

211

Kinetics of coal pyrolysis  

Science Conference Proceedings (OSTI)

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.

Seery, D.J.; Freihaut, J.D.; Proscia, W.M. (United Technologies Research Center, East Hartford, CT (USA)); Howard, J.B.; Peters, W.; Hsu, J.; Hajaligol, M.; Sarofim, A. (Massachusetts Inst. of Tech., Cambridge, MA (USA)); Jenkins, R.; Mallin, J.; Espindola-Merin, B. (Pennsylvania State Univ., University Park, PA (USA)); Essenhigh, R.; Misra, M.K. (Ohio State Univ., Columbus, OH (USA))

1989-07-01T23:59:59.000Z

212

INFRARED ABSORPTION SPECTROSCOPY AND CHEMICAL KINETICS OF FREE RADICALS  

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

mNAL PERFORMANCE REPORT mNAL PERFORMANCE REPORT for INFRARED ABSORPTION SPECTROSCOPY AND CHEMICAL KINETICS OF FREE RADICALS DE-FG05-85ER13439 1-AUG-1985 to 31-JUL-1994 Robert F. Curl and Graham P. Glass Principal Investigators Introduction This research was directed at the detection, monitoring, and study (by infrared absorption spectroscopy) of the chemical kinetic behavior of small free radical species thought to be important intermediates in combustion. The work typically progressed from the detection and analysis of the infrared spectrum of combustion radical to the utilization of the infrared spectrum thus obtained in the investigation of chemical kinetics of the radical species. The methodology employed was infrared kinetic spectroscopy. In this technique the radical is produced by UV flash photolysis using an excimer laser and then

213

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...

214

Direct measurements of the nonlinear index of refraction of water at 815 and 407 nm using single-shot supercontinuum spectral interferometry  

E-Print Network (OSTI)

, College Park, Maryland 20742, USA 2 Plasma Physics Division, Naval Research Laboratory, Washington, DC window 2 ps for measurement of the non- linear response of an optical medium. Such measurements can show windows, chosen to minimize self-phase modulation of the pump and cross phase modulation of the probe

Milchberg, Howard

215

Direct total cross section measurement of the {sup 16}O({alpha}, {gamma}){sup 20}Ne reaction at E{sub c.m.}=2.26 MeV  

Science Conference Proceedings (OSTI)

In stellar helium burning, {sup 16}O represents the endpoint of the helium-burning sequence due to the low rate of {sup 16}O({alpha},{gamma}){sup 20}Ne. We present a new direct measurement of the total capture reaction rate of {sup 16}O({alpha},{gamma}){sup 20}Ne at E{sub c.m.}=2.26 MeV employing the DRAGON recoil separator. For the first time, the total S factor and its contributing direct capture transitions could be determined in one experiment.

Hager, U.; Greife, U. [Colorado School of Mines, Golden, Colorado (United States); Brown, J. R. [Department of Physics, University of York, York, YO10 5DD (United Kingdom); Buchmann, L.; Fallis, J.; Hutcheon, D.; Ottewell, D.; Ruiz, C.; Sjue, S. [TRIUMF, Vancouver, Canada V6T 2A3 (Canada); Carmona-Gallardo, M. [Instituto de Estructura de la Materia, CSIC E-28006 Madrid (Spain); Erikson, L. [Pacific Northwest National Laboratory, Richland, WA (United States); Vockenhuber, C. [ETH Zurich, Zurich (Switzerland)

2011-08-15T23:59:59.000Z

216

5, 86898714, 2005 The Kinetic  

E-Print Network (OSTI)

Technical Note: Simulating chemical systems in Fortran90 and Matlab with the Kinetic PreProcessor KPP-2.1 A estimation techniques, and variational chemical data assimilation applications require the development of ef- ficient tools for the computational simulation of chemical kinetics systems. From a numerical point

Paris-Sud XI, Université de

217

Nonlinear effects in kinetic resolutions  

E-Print Network (OSTI)

The impact of nonlinear effects in the asymmetric catalysis of kinetic resolutions is analyzed. It is found with minimal assumptions that the kinetics of homocompetitive reactions should apply generally to kinetic resolutions involving partially resolved catalysts, and this is supported by experimental observations with the Jacobsen hydrolytic kinetic resolution (HKR) of epoxides. The criterion for a nonlinear effect in asymmetric catalysis--a nonlinear correlation between the enantiomeric excess in a choral ligand and the product enantiomeric excess obtained from a reaction--is examined. The nonlinear effect idea is found to be generalizable to kinetic resolutions and other reactions by replacing consideration of the product enantiomeric excess with the quantity (k[]/k[]-1)/(k[]/k[]+1), a differential kinetic enantiomeric enhancement (DKEE). A nonlinear effect may then be defined by a nonlinear correlation between the DKEE and the chiral ligand enantiomeric excess. The application of these ideas to previously reported kinetic resolutions of sulfoxides and to nonlinear effects in the Jacobsen HKR is described. Relatively small nonlinear effects in kinetic resolutions are sufficient to obtain large asymmetric amplifications. A catalyst modification in the Jacobsen HKR also allows for the development of a novel recyclable system for the iterative enhancement of optical activity.

Johnson, Derrell W.

1999-01-01T23:59:59.000Z

218

Direct Photons at RHIC  

E-Print Network (OSTI)

Direct photons are ideal tools to investigate kinematical and thermodynamical conditions of heavy ion collisions since they are emitted from all stages of the collision and once produced they leave the interaction region without further modification by the medium. The PHENIX experiment at RHIC has measured direct photon production in p+p and Au+Au collisions at 200 GeV over a wide transverse momentum ($p_T$) range. The $p$ + $p$ measurements allow a fundamental test of QCD, and serve as a baseline when we try to disentangle more complex mechanisms producing high $p_T$ direct photons in Au+Au. As for thermal photons in Au+Au we overcome the difficulties due to the large background from hadronic decays by measuring "almost real" virtual photons which appear as low invariant mass $e^+e^-$ pairs: a significant excess of direct photons is measured above the above next-to-leading order perturbative quantum chromodynamics calculations. Additional insights on the origin of direct photons can be gained with the study of the azimuthal anisotropy which benefits from the increased statistics and reaction plane resolution achieved in RHIC Year-7 data.

G. David; for the PHENIX Collaboration

2008-10-06T23:59:59.000Z

219

Preprint typeset using L ATEX style emulateapj ON THE KINETIC ENERGY AND RADIATIVE EFFICIENCY OF GAMMA-RAY BURSTS  

E-Print Network (OSTI)

Using measured X-ray luminosities to 17 Gamma-Ray Bursts (GRBs) during the afterglow phase and accounting for radiative losses, we calculate the kinetic energy of these bursts and investigate its relation to other GRB properties. We then use the observed radiated energy during the prompt phase to determine the radiative efficiency of these bursts, and explore how the efficiency relates to other GRB observables. We find that the kinetic energy in the afterglow phase is directly correlated with the radiated energy, total energy as well as possibly the jet opening angle and spectral peak energy. More importantly, we find the intriguing fact that the efficiency is correlated with the radiated energy, and mildly with the total energy, jet opening angle and spectral peak energy. XRF020903 also seems to follow the trends we find for our GRB sample. We discuss the implications of these results for the GRB radiation and jet models. 1.

Nicole M. Lloyd-ronning; Bing Zhang

2008-01-01T23:59:59.000Z

220

Directional Response of Ocean Waves to Changing Wind Direction  

Science Conference Proceedings (OSTI)

When analysing wave measurements in turning winds, one usually assumes that the rate of change of mean wave direction is determined by the angle between ?w, the wind direction, and ?o, the mean wave direction; however, it is well known that this ...

Gao Quanduo; Gerbrand Komen

1993-07-01T23:59:59.000Z

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221

Thermodynamics and Kinetics Information at NIST  

Science Conference Proceedings (OSTI)

... Staff (06/28/2013). Thermodynamic & Kinetic Data for Sustainable Energy (10/05/2012). Thermodynamics and Kinetics Group (07/06/2013 ...

2010-05-24T23:59:59.000Z

222

Determination of cohesive and normal stresses and simulation of fluidization using kinetic theory  

SciTech Connect

The general objective of this study is focused on the solid stresses involved in gas-solid flow. These stresses are generally included in the momentum conservation equations, essentially for stability and to prevent particles from collapsing to unreasonably low values of gas volume fraction. The first half of this work undertakes the measurement of the stresses in various powders by direct means, while the second part uses a newly developed kinetic theory constitutive equation for stress to predict the flow and also the solids viscosity in a CFB. The cohesive or tensile stress found to exist in some classes of powders is measured using a Cohetester, based on which a cohesive force model is derived, which is sensitive to the characteristic properties of the powder material. The normal stress is measured using a Consolidometer, and the powder solids modulus is obtained as a function of the volume fraction. The solids modulus is seen to vary with particle size and particle type, with the smaller size particles being more compressible. The simulation of flow in the CFB using Gidaspow's (1991) extension of Ding's (1990) kinetic theory model to dilute phase flow, predicts realistic values of solids viscosity that are comparable to viscosities obtained experimentally by Miller (1991). However, to obtain a match between the two the value of the restitution coefficient has to be close to unity. The flow behavior showed periodic oscillations of flow (turbulence) as seen in a real system. 26 refs., 51 figs., 1 tab.

Bezbaruah, R.

1991-08-01T23:59:59.000Z

223

Direct measurement of the {sup 11}C({alpha},p){sup 14}N reaction at CRIB: A path from pp-chain to CNO  

SciTech Connect

We determined the total reaction rate of the {sup 11}C({alpha},p){sup 14}N reaction relevant to the nucleosynthesis in explosive hydrogen-burning stars. The measurement was performed by means of the thick target method in inverse kinematics with {sup 11}C RI beams. We performed the identification of the ground-state transition and excited-state transitions using time-of-flight information for the first time.

Hayakawa, S.; Kubono, S.; Kahl, D.; Yamaguchi, H.; Binh, D. N.; Hashimoto, T.; Wakabayashi, Y.; He, J. J.; Iwasa, N.; Kato, S.; Komatsubara, T.; Kwon, Y. K.; Teranishi, T.; Wanajo, S. [Laboratori Nazionali del Sud, Istituto Nazionale di Fisica Nucleare (Italy); Nishina Center, RIKEN (Japan); Center for Nuclear Study, University of Tokyo (Japan)

2012-11-20T23:59:59.000Z

224

Direct measurement of the breakout reaction {sup 11}C({alpha},p){sup 14}N in explosive hydrogen-burning process  

Science Conference Proceedings (OSTI)

We determined the {sup 11}C({alpha},p){sup 14}N reaction rate relevant to the nucleosynthesis in explosive hydrogen-burning stars. The measurement was performed by means of the thick target method in inverse kinematics with {sup 11}C RI beams. We derived the excitation functions for the ground-state transition and excited-state transitions using time-of-flight information for the first time. The present reaction rate is compared to the previous one.

Hayakawa, S.; Kubono, S.; Kahl, D.; Yamaguchi, H.; Binh, Dam N.; Hashimoto, T.; Wakabayashi, Y.; He, J. J.; Iwasa, N.; Kato, S.; Komatsubara, T.; Kwon, Y. K.; Teranishi, T.; Wanajo, S. [Center for Nuclear Study, Graduate of Science, University of Tokyo (Japan) and Institute of Physics (Japan); RCNP, Osaka University (Japan); Japan Atomic Energy Agency (Japan); Institute of Modern Physics (Japan); Department of Physics, Tohoku University (Japan); Department of Physics, Yamagata University (Japan); Department of Physics, University of Tsukuba (Japan); Department of Physics, Chung Ang University (Korea, Republic of); Department of Physics, Kyushu University (Japan); Institute for the Physics and Mathematics of the Universe, University of Tokyo (Japan)

2012-11-12T23:59:59.000Z

225

Asphalt Oxidation Kinetics and Pavement Oxidation Modeling  

E-Print Network (OSTI)

Most paved roads in the United States are surfaced with asphalt. These asphalt pavements suffer from fatigue cracking and thermal cracking, aggravated by the oxidation and hardening of asphalt. This negative impact of asphalt oxidation on pavement performance has not been considered adequately in pavement design. Part of the reason is that the process of asphalt oxidation in pavement is not well understood. This work focused on understanding the asphalt oxidation kinetics and on developing pavement oxidation model that predicts asphalt oxidation and hardening in pavement under environmental conditions. A number of asphalts were studied in laboratory condition. Based on kinetics data, a fast-rate ? constant-rate asphalt oxidation kinetics model was developed to describe the early nonlinear fast-rate aging period and the later constant-rate period of asphalt oxidation. Furthermore, reaction kinetics parameters for the fast-rate and constant-rate reactions were empirically correlated, leading to a simplified model. And the experimental effort and time to obtain these kinetics parameters were significantly reduced. Furthermore, to investigate the mechanism of asphalt oxidation, two antioxidants were studied on their effectiveness. Asphalt oxidation was not significantly affected. It was found that evaluation of antioxidant effectiveness based on viscosity only is not reliable. The asphalt oxidation kinetics model was incorporated into the pavement oxidation model that predicts asphalt oxidation in pavement. The pavement oxidation model mimics the oxidation process of asphalt in real mixture at pavement temperatures. A new parameter, diffusion depth, defined the oxygen diffusion region in the mastic. A field calibration factor accounted for the factors not considered in the model such as the effect of small aggregate particles on oxygen diffusion. Carbonyl area and viscosity of binders recovered from field cores of three pavements in Texas were measured and were used for model calibration and validation. Results demonstrated that the proposed model estimates carbonyl growth over time in pavement, layer-by-layer, quite well. Finally, this work can be useful for incorporating asphalt oxidation into a pavement design method that can predict pavement performance with time and for making strategic decisions such as optimal time for maintenance treatments.

Jin, Xin

2012-05-01T23:59:59.000Z

226

NETL: Mercury Emissions Control Technologies - Bench Scale Kinetics of  

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

Bench Scale Kinetics of Mercury Reactions in FGD Liquors Bench Scale Kinetics of Mercury Reactions in FGD Liquors When research into the measurement and control of Hg emissions from coal-fired power plants began in earnest in the early 1990s, it was observed that oxidized mercury can be scrubbed at high efficiency in wet FGD systems, while elemental mercury can not. In many cases, elemental mercury concentrations were observed to increase slightly across wet FGD systems, but this was typically regarded as within the variability of the measurement methods. However, later measurements have shown substantial re-emissions from some FGD systems. The goal of this project is to develop a fundamental understanding of the aqueous chemistry of mercury (Hg) absorbed by wet flue gas desulfurization (FGD) scrubbing liquors. Specifically, the project will determine the chemical reactions that oxidized mercury undergoes once absorbed, the byproducts of those reactions, and reaction kinetics.

227

Rhodopsin kinetics in the cat retina  

SciTech Connect

The bleaching and regeneration of rhodopsin in the living cat retina was studied by means of fundus reflectometry. Bleaching was effected by continuous light exposures of 1 min or 20 min, and the changes in retinal absorbance were measured at 29 wavelengths. For all of the conditions studied (fractional bleaches of from 65 to 100%), the regeneration of rhodopsin to its prebleach levels required greater than 60 min in darkness. After the 1-min exposures, the difference spectra recorded during the first 10 min of dark adaptation were dominated by photoproduct absorption, and rhodopsin regeneration kinetics were obscured by these intermediate processes. Extending the bleaching duration to 20 min gave the products of photolysis an opportunity to dissipate, and it was possible to follow the regenerative process over its full time-course. It was not possible, however, to fit these data with the simple exponential function predicted by first-order reaction kinetics. Other possible mechanisms were considered and are presented in the text. Nevertheless, the kinetics of regeneration compared favorably with the temporal changes in log sensitivity determined electrophysiologically by other investigators. Based on the bleaching curve for cat rhodopsin, the photosensitivity was determined and found to approximate closely the value obtained for human rhodopsin; i.e., the energy Ec required to bleach 1-e-1 of the available rhodopsin was 7.09 log scotopic troland-seconds (corrected for the optics of the cat eye), as compared with approximately 7.0 in man.

Ripps, H.; Mehaffey, L.; Siegel, I.M.

1981-03-01T23:59:59.000Z

228

Metal reduction kinetics in Shewanella  

Science Conference Proceedings (OSTI)

Motivation: Metal reduction kinetics have been studied in cultures of dissimilatory metal reducing bacteria which include the Shewanella oneidensis strain MR-1. Estimation of system parameters from time-series data faces obstructions in ...

Raman Lall; Julie Mitchell

2007-09-01T23:59:59.000Z

229

Time-resolved broadband cavity-enhanced absorption spectroscopy for chemical kinetics.  

SciTech Connect

Experimental measurements of elementary reaction rate coefficients and product branching ratios are essential to our understanding of many fundamentally important processes in Combustion Chemistry. However, such measurements are often impossible because of a lack of adequate detection techniques. Some of the largest gaps in our knowledge concern some of the most important radical species, because their short lifetimes and low steady-state concentrations make them particularly difficult to detect. To address this challenge, we propose a novel general detection method for gas-phase chemical kinetics: time-resolved broadband cavity-enhanced absorption spectroscopy (TR-BB-CEAS). This all-optical, non-intrusive, multiplexed method enables sensitive direct probing of transient reaction intermediates in a simple, inexpensive, and robust experimental package.

Sheps, Leonid; Chandler, David W.

2013-04-01T23:59:59.000Z

230

Theoretical Studies in Chemical Kinetics  

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

Theoretical Studies in Chemical Kinetics ^ ^ iCi| Theoretical Studies in Chemical Kinetics ^ ^ iCi| under AEC Contract A T (30-1)-3780 " â–  ' Annual Report (1970) Principal In-vestigator: Martin Karpins Institution: Harvard University The research performed under this contract can best be sunmarized under several headings. (a) Alkali-Halideg Alkali-Halide (MX^ M*X*) Exchange Reactions. This project is being continued. A careful study of certain

231

On kinetic description of electromagnetic processes in a quantum plasma  

E-Print Network (OSTI)

A nonlinear kinetic equation for nonrelativistic quantum plasma with electromagnetic interaction of particles is obtained in the Hartree's mean-field approximation. It is cast in a convenient form of Vlasov-Boltzmann-type equation with "quantum interference integral", that allows for relatively straightforward modification of existing classical Vlasov codes to incorporate quantum effects (quantum statistics and quantum interference of overlapping particles wave functions), without changing the bulk of the codes. Such modification (upgrade) of existing Vlasov codes may provide a direct and effective path to numerical simulations of nonlinear electrostatic and electromagnetic phenomena in quantum plasmas, especially of processes where kinetic effects are important (e.g., modulational interactions and stimulated scattering phenomena involving plasma modes at short wavelengths or high-order kinetic modes, dynamical screening and interaction of charges in quantum plasma, etc.) Moreover, numerical approaches involv...

Tyshetskiy, Y O; Kompaneets, R

2011-01-01T23:59:59.000Z

232

Measurement of direct photons in s(NN)**1/2 = 200 GeV p+p and Au+Au collisions with the PHENIX Experiment at RHIC  

E-Print Network (OSTI)

The measurement of direct photons in s(NN)**1/2 = 200 GeV p+p and Au+Au collisions is presented. The signal is compared to NLO pQCD calculations, which, in case of Au+Au, are scaled with the number of underlying nucleon-nucleon collisions. The agreement of the calculation with the data in both cases confirms the scaling of hard processes with the number of nucleon-nucleon collisions and supports the explanation of the earlier-observed pion suppression as a final-state effect.

Stefan Bathe; for the PHENIX Collaboration

2005-11-22T23:59:59.000Z

233

PBXN-9 Ignition Kinetics and Deflagration Rates  

SciTech Connect

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.

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

2008-04-24T23:59:59.000Z

234

A Chemical Kinetic Model of Transcriptional Elongation  

E-Print Network (OSTI)

A chemical kinetic model of the elongation dynamics of RNA polymerase along a DNA sequence is introduced. The proposed model governs the discrete movement of the RNA polymerase along a DNA template, with no consideration given to elastic effects. The model's novel concept is a ``look-ahead'' feature, in which nucleotides bind reversibly to the DNA prior to being incorporated covalently into the nascent RNA chain. Results are presented for specific DNA sequences that have been used in single-molecule experiments of the random walk of RNA polymerase along DNA. By replicating the data analysis algorithm from the experimental procedure, the model produces velocity histograms, enabling direct comparison with these published results.

Yujiro Richard Yamada; Charles S. Peskin

2006-03-12T23:59:59.000Z

235

Kinetics driving high-density chlorine plasmas  

Science Conference Proceedings (OSTI)

A simple fluid model was developed in order to investigate the driving kinetics of neutral and charged species in high-density chlorine plasmas. It was found that the dissociation degree of Cl{sub 2} molecules is directly linked to the power balance of the discharge which controls the electron density. The model was also used to identify those reactions that could be neglected in the particle balance of charged species and those that must be included. Our results further indicate that diffusion losses need to be considered up to a pressure that depends on magnetic-field intensity and reactor aspect ratio. Finally, it is shown that the dominant charged carriers are linked to the dissociation level of Cl{sub 2} molecules.

Stafford, L.; Margot, J.; Vidal, F.; Chaker, M.; Giroux, K.; Poirier, J.-S.; Quintal-Leonard, A.; Saussac, J. [Department de physique, Universite de Montreal, Montreal, Quebec (Canada); INRS-Energie, Materiaux et Telecommunications, Varennes, Quebec (Canada); Department de physique, Universite de Montreal, Montreal, Quebec (Canada)

2005-09-15T23:59:59.000Z

236

Spectroscopy, Kinetics, and Dynamics of Combustion Radicals  

SciTech Connect

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.

Nesbitt, David J. [Research/Professor

2013-08-06T23:59:59.000Z

237

Kinetics of Oxygen Reduction in LSM and LSCF  

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

1.00E-05 1.00E-04 1.00E-03 1.00E-02 1.00E-01 1.00E+00 -30 -25 -20 -15 -10 -5 0 5 LogpO2atm VA''' VB''' VO** MnB* MnBx MnB' Kinetic Measurements Using Polycrystalline...

238

Detailed measurement of the e+e- pair continuum in p+p and Au+Au collisions at sqrt(s_NN)=200 GeV and implications for direct photon production  

E-Print Network (OSTI)

PHENIX has measured the e^+e^- pair continuum in sqrt(s_NN)=200 GeV Au+Au and p+p collisions over a wide range of mass and transverse momenta. The e^+e^- yield is compared to the expectations from hadronic sources, based on PHENIX measurements. In the intermediate mass region, between the masses of the phi and the J/psi meson, the yield is consistent with expectations from correlated c^bar-c production, though other mechanisms are not ruled out. In the low mass region (below the phi) the p+p inclusive mass spectrum is well described by known contributions from light meson decays. In contrast, the Au+Au minimum bias inclusive mass spectrum in this region shows an enhancement by a factor of 4.7+/-0.4(stat)+/-1.5(syst)+/-0.9(model) At low mass (m_eedirect photons. This excess is used to infer the yield of real direct photons. In central Au+Au collisions, the excess of the direct photon yield over the p+p is exponential in p_T, with inverse slope T=221+/-19(stat)+/-19(syst) MeV. Hydrodynamical models with initial temperatures ranging from T_init ~=300--600 MeV at times of 0.6--0.15 fm/c after the collision are in qualitative agreement with the direct photon data in Au+Au. For low p_T<1 GeV/c the low mass region shows a further significant enhancement that increases with centrality and has an inverse slope of T ~=100 MeV. Theoretical models under predict the low mass, low p_T enhancement.

PHENIX Collaboration; A. Adare

2009-12-01T23:59:59.000Z

239

Fragmentation of water by ion impact: Kinetic energy release spectra  

SciTech Connect

The fragmentation of isolated water molecules on collision with 450-keV Ar{sup 9+} has been studied using time-of-flight mass spectrometry employing multihit detection. The kinetic energy release spectrum for the dissociation of [H{sub 2}O]{sup 2+ White-Star} into (H{sup White-Star },H{sup +},O{sup +}) fragments has been measured where H{sup White-Star} is a neutral Rydberg hydrogen atom. Ab initio calculations are carried out for the lowest states of [H{sub 2}O]{sup q+} with q=2 and 3 to help interpret the kinetic energy release spectra.

Rajput, Jyoti; Safvan, C. P. [Department of Physics and Astrophysics, University of Delhi, Delhi 110007 (India); Inter-University Accelerator Centre, Aruna Asaf Ali Marg, New Delhi 110067 (India)

2011-11-15T23:59:59.000Z

240

Molecular beam kinetics  

SciTech Connect

The design of a crossed molecular beam ''supermachine'' for neutral-- neutral collisions is discussed. The universal electron bombardment ionizer, mass filter, and ion detection system of the detector, the supersonic nozzle sources, the differential pumping arrangement for the sources and detector, the time-of-flight detection of scattered products, and the overall configuration of the apparatus are described. The elastic scattering of two systems, CH$sub 4$ + Ar and NH$sub 3$ + Ar, has been measured using the supermachine with two supersonic nozzle sources. The rainbow structure and the interference oscillations are seen in each system. The best fit to the data was found using a Morse--Spline--Van der Waals (MSV) potential. The three potential parameters epsilon, r/sub m/, and $beta$ were found to be 2.20(+-0.04) x 10$sup -14$ ergs, 3.82(+-0.04)A, and 7.05 +- 0.20 for CH$sub 4$ + Ar, and 2.21(+-0.04) x 10$sup - 14$ ergs 3.93 (+-0.05)A, and 8.45 +- 0.30 for NH$sub 3$ + Ar. A new phenomenon in crossed molecular beams of condensation of a molecule on a cluster to form a complex was observed. A bromine molecule condensed on clusters of chlorine (Cl$sub 2$)/sub chi/ and ammonia (NH$sub 3$)/sub chi/. The value of chi for measurements in these experiments ranges from 7 to 40 for chlorine clusters and from 10 to 70 ammonia clusters. (auth)

Behrens, R. Jr.

1975-11-01T23:59:59.000Z

Note: This page contains sample records for the topic "direct kinetic measurements" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
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241

ARM - Measurement - Shortwave narrowband direct normal irradiance  

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

Incidence Multifilter Radiometer External Instruments USDARAD : US Department of Agriculture (USDA) Radiation Monitoring Data Field Campaign Instruments AOD : Aerosol Optical...

242

Kinetics of PBX9404 Aging  

DOE Green Energy (OSTI)

PBX 9404 is an early formulation of HMX from which we can learn about the effects of aging in the weapons stockpile. Of particular interest is the presence of 3% nitrocellulose in PBX 9404 as an energetic binder. Nitrocellulose is used pervasively in smokeless gunpowders and was formerly used extensively in the film and art preservation industries. It is well known that nitrocellulose decomposes autocatalytically, and stabilizers, such as the diphenylamine used in PBX 9404, are used to retard its decomposition. Even so, its lifetime is still limited, and the reactions eventually leading to catastrophic autocatalysis are still not understood well despite years of work. In addition to reducing the available energy in the explosive, degradation of nitrocellulose affects the mechanical properties of the pressed PBX 9404 parts by the associated reduction in molecular weight, which reduces the strength of the binder. A structural formula for a monomer of the nitrocellulose used in PBX 9404 is shown. The initial nitration level is 2.3 of 3.0 possible sites, and they have different reactivities. Degradation of nitrocellulose affects many properties. As an aid in examining historical chemical analysis data, several measures of degradation are given for the simple replacement of a nitro group with a hydrogen. The weight percent of nitrocellulose remaining for an initial concentration of 3% as used in PBX 9404 is also given. Of course, the real degradation reaction is more complicated, including chain scission and crosslinking reactions giving other gas species. During the course of this work, we spent considerable time addressing the question, ''Why is PBX 9404 blue?'' There was actually considerable controversy in the color evolution with aging, and the situation was clarified by Ben Richardson at Pantex. Workers there assured us that PBX 9404 starts with an ivory color. Drying the prill prior to pressing turns it a mottled blue, and well-preserved prill samples retain a blue color decades after formulation. Subsequently, heat and light both send it through a progression of colors from grayish blue, blue-green, green, brown, dirty yellow, mottled tan, and eventually pale tan. The progression is accelerated by oxygen and possibly moisture, as has been shown in several accelerated aging studies. The precise compounds causing the color evolution are uncertain, but they are undoubtedly a progression of quinoidal, nitroso, and nitrated DPA compounds. For example, paranitroso DPA is deep blue. Unfortunately, the location of various nitrated DPAs, which ranged from yellow to orange to red to brown and which were used by Pantex as analytical standards in the 1970s, is not currently known. While the color change is indicative of aging, it is by no means a quantitative measure of the extent of nitrocellulose degradation. Inspection of the literature yielded a variety of kinetic models, and the activation energy typically ranges from 25-35 kcal/mol for T<100 C. This literature qualitatively predicts times for 30% decomposition ranging from a few days at 100 C to 1-2 years at 50 C to 50 years at room temperature. To develop a quantitative model, we used the data of Leider and Seaton, which were collected at conditions most closely matching stockpile conditions for any data set we had available. They used PBX 9404 heated as pressed pellets in closed vessels at temperatures ranging from 50 to 100 C for times up to three years, and they report mass loss, gas yield and composition, and chemical analysis of the residual solid by methods used in stockpile surveillance. Initial kinetic analysis of the weight of remaining nitrocellulose as measured by liquid chromatography and the loss of nitrate esters by a colorimetric technique gave an activation energy of 27 kcal/mol. However, the reaction is complex due to the different stability of the three nitroester positions, and this complexity required either parallel first-order reactions or an nth-order reaction (n=3.6), which is mathematically equivalent to a Gamma distribution of frequency factors

Burnham, A K; Fried, L E

2006-09-11T23:59:59.000Z

243

Kinetic Wave Power | Open Energy Information  

Open Energy Info (EERE)

Kinetic Wave Power Jump to: navigation, search Name Kinetic Wave Power Address 2861 N Tupelo St Place Midland Zip 48642 Sector Marine and Hydrokinetic Phone number 989-839-9757...

244

A new water anomaly: the temperature dependence of the proton mean kinetic energy  

E-Print Network (OSTI)

The mean kinetic energy of protons in water is determined by Deep Inelastic Neutron Scattering experiments, performed above and below the temperature of maximum density and in the supercooled phase. The temperature dependence of this energy shows an anomalous behavior, as it occurs for many water properties. In particular two regions of maximum kinetic energy are identified: the first one, in the supercooled phase in the range 269 K - 272 K, and a second one above 273 K. In both these regions the measured proton kinetic energy exceedes the theoretical prediction based on a semi-classical model. Noteworthy, the proton mean kinetic energy has a maximum at 277 K, the temperature of the maximum density of water. In the supercooled metastable phase the measured mean kinetic energy and the proton momentum distribution clearly indicate proton delocalization between two H-bonded oxygens.

Davide Flammini; Fabio Bruni; Maria Antonietta Ricci

2009-01-27T23:59:59.000Z

245

Oxidation Kinetics Modeling Applying Phase Field Approach  

Science Conference Proceedings (OSTI)

Presentation Title, Oxidation Kinetics Modeling Applying Phase Field Approach ... chemical reaction rates will increase exponentially and environmental attack ...

246

Kinetics of Nano Ti Carbides Precipitation  

Science Conference Proceedings (OSTI)

About this Abstract. Meeting, Materials Science & Technology 2011. Symposium, Steel Product Metallurgy and Applications. Presentation Title, Kinetics of Nano ...

247

Modeling & Characterization of Harvestable Kinetic Energy for ...  

Science Conference Proceedings (OSTI)

... gov 301.975-5479. Modeling & Characterization of Harvestable Kinetic Energy for Wearable Medical Sensors. RF-enabled ...

2011-03-14T23:59:59.000Z

248

Kinetics of zeolite dealumination in steam  

DOE Green Energy (OSTI)

Zeolite dealumination is a well known phenomenon that contributes to the deactivation or activation of catalysts in several different applications. The most obvious effect is in acid catalysis where dealumination under reaction conditions removes the Broensted sites, thus deactivating the catalyst. The authors are interested in the use of cation exchanged zeolites as selective reduction catalysts for removal of NO{sub x} from exhaust streams, particularly from automotive exhaust. In this case, copper exchanged ZSM-5 has been shown to be an effective catalyst for the generic reaction of NO{sub x} with hydrocarbons. However, high temperature and steam in combustion exhaust causes dealumination and consequent migration of copper out of the zeolite structure resulting in rapid deactivation of the catalyst. Dealumination of zeolites has been reported by many authors in uncountable papers and cannot be reviewed here. However, to the authors` knowledge there are no reports on the kinetics of dealumination under varying conditions of temperature and steam. By measuring the kinetics of dealumination with different zeolites and exchange cations they expect to develop working models of the dealumination process that will allow control of zeolite deactivation. This manuscript is a description of the basic techniques used and a progress report on the very beginning of this study.

Hughes, C.D.; Labouriau, A.; Crawford, S.N.; Romero, R.; Quirin, J.; Earl, W.L.

1998-08-01T23:59:59.000Z

249

Aging Effects on the Kinetics of Cesium Desorption from Vermiculite And Contaminated Soil  

E-Print Network (OSTI)

Aging Effects on the Kinetics of Cesium Desorption from Vermiculite And Contaminated Soil A. M), it is important to determine how aging affects 137 Cs desorption. This study uses a batch technique to measure 0

Sparks, Donald L.

250

The Kinetic Energy of Hailfalls. Part IV: Patterns of Hailpad and Radar Data  

Science Conference Proceedings (OSTI)

Ground-and radar-measured patterns of hail kinetic energy from eight hailstorms have been compared. The radar patterns were shifted horizontally in such a way that the correlation coefficient between the ground and radar data reaches a maximum. ...

W. Schmid; H. H. Schiesser; A. Waldvogel

1992-10-01T23:59:59.000Z

251

Millisecond Kinetics of Nanocrystal Cation Exchange Using Microfluidic X-ray Absorption Spectroscopy  

E-Print Network (OSTI)

nanocrystal with DDA, R CdSe was calculated to be 3.4 nm. Rto measure the kinetics of the CdSe-to-Ag 2 Se nanocrystalthe millisecond mixing of CdSe nanocrystal and Ag + reactant

Chan, Emory M.; Marcus, Matthew A.; Fakra, Sirine; Elnaggar, Mariam S.; Mathies, Richard A.; Alivisatos, A. Paul

2007-01-01T23:59:59.000Z

252

The Kinetic Energy of Hailfalls. Part III: Sampling Errors Inferred, from Radar Data  

Science Conference Proceedings (OSTI)

The representativeness of hailfall kinetic energies derived from point measurements of networks is studied by means of radar data of hail cells. The 202 cells were observed within a radius of 60 km from the 10 cm radar. Different Cartesian ...

A. Waldvogel; W. Schmid

1982-09-01T23:59:59.000Z

253

Stepping and crowding: statistical kinetics from an exclusion process perspective  

E-Print Network (OSTI)

Motor enzymes are remarkable molecular machines that use the energy derived from the hydrolysis of a nucleoside triphosphate to generate mechanical movement, achieved through different steps that constitute their kinetic cycle. These macromolecules, nowadays investigated with advanced experimental techniques to unveil their molecular mechanisms and the properties of their kinetic cycles, are implicated in many biological processes, ranging from biopolymerisation (RNA polymerases, ribosomes,...) to intracellular transport (motor proteins such as kinesins or dyneins). Although the kinetics of individual motors is well studied on both theoretical and experimental grounds, the repercussions of their stepping cycle on the collective dynamics is still to be understood. Advances in this direction will improve our comprehension of transport process in the natural intracellular medium, where processive motor enzymes might operate in crowded conditions. In this work, we therefore extend the current statistical kinetic analysis to study collective transport phenomena of motors in terms of lattice gas models belonging to the exclusion process class. Via numerical simulations, we show how to interpret and use the randomness calculated from single particle trajectories in crowded conditions. Importantly, we also show that time fluctuations and non-Poissonian behavior are intrinsically related to spatial correlations and the emergence of large, but finite, clusters of co-moving motors. The properties unveiled by our analysis have important biological implications on the collective transport characteristics of processive motor enzymes in crowded conditions.

Luca Ciandrini; M. Carmen Romano; A. Parmeggiani

2013-12-06T23:59:59.000Z

254

Reduced and Validated Kinetic Mechanisms for Hydrogen-CO-sir Combustion in Gas Turbines  

DOE Green Energy (OSTI)

Rigorous experimental, theoretical, and numerical investigation of various issues relevant to the development of reduced, validated kinetic mechanisms for synthetic gas combustion in gas turbines was carried out - including the construction of new radiation models for combusting flows, improvement of flame speed measurement techniques, measurements and chemical kinetic analysis of H{sub 2}/CO/CO{sub 2}/O{sub 2}/diluent mixtures, revision of the H{sub 2}/O{sub 2} kinetic model to improve flame speed prediction capabilities, and development of a multi-time scale algorithm to improve computational efficiency in reacting flow simulations.

Yiguang Ju; Frederick Dryer

2009-02-07T23:59:59.000Z

255

Kinetically Dominated FRII Radio Sources  

E-Print Network (OSTI)

The existence of FR II objects that are kinetically dominated, the jet kinetic luminosity, $Q$, is larger than the total thermal luminosity (IR to X-ray) of the accretion flow, $L_{bol}$, is of profound theoretical interest. Such objects are not expected in most theoretical models of the central engine of radio loud AGN. Thus, establishing such a class of objects is an important diagnostic for filtering through the myriad of theoretical possibilities. This paper attempts to establish a class of quasars that have existed in a state of kinetic dominance, $R(t)\\equiv Q(t)/L_{bol}(t)>1$, at some epoch, $t$. It is argued that the 10 quasars in this article with a long term time average $Q(t)$, $\\bar{Q}$, that exceed $L_{Edd}$ are likely to have satisfied the condition $R(t)>1$ either presently or in the past based on the rarity of $L_{bol}>L_{Edd}$ quasars. Finally, the existence of these sources is discussed in the context of the theory of the central engine.

Brian Punsly

2006-10-02T23:59:59.000Z

256

Measurement of B(B-->X_s {\\gamma}), the B-->X_s {\\gamma} photon energy spectrum, and the direct CP asymmetry in B-->X_{s+d} {\\gamma} decays  

E-Print Network (OSTI)

The photon spectrum in B --> X_s \\gamma decay, where X_s is any strange hadronic state, is studied using a data sample of (382.8\\pm 4.2) \\times 10^6 e^+ e^- --> Upsilon(4S) --> BBbar events collected by the BABAR experiment at the PEP-II collider. The spectrum is used to measure the branching fraction B(B --> X_s \\gamma) = (3.21 \\pm 0.15 \\pm 0.29 \\pm 0.08)\\times 10^{-4} and the first, second, and third moments = 2.267 \\pm 0.019 \\pm 0.032 \\pm 0.003 GeV, )^2> = 0.0484 \\pm 0.0053 \\pm 0.0077 \\pm 0.0005 GeV^2, and )^3> = -0.0048 \\pm 0.0011 \\pm 0.0011 \\pm 0.0004 GeV^3, for the range E_\\gamma > 1.8 GeV, where E_\\gamma is the photon energy in the B-meson rest frame. Results are also presented for narrower E_\\gamma ranges. In addition, the direct CP asymmetry A_{CP}(B --> X_{s+d} \\gamma) is measured to be 0.057 \\pm 0.063. The spectrum itself is also unfolded to the B-meson rest frame; that is the frame in which theoretical predictions for its shape are made.

,

2012-01-01T23:59:59.000Z

257

EU Metric Directive  

Science Conference Proceedings (OSTI)

... View EU Metric Directive Commission Services Working Document PDF ... of European Union (EU) Meeting on Metric Directives (2005); Packaging ...

2012-12-13T23:59:59.000Z

258

The development of a chemical kinetic measurement apparatus and the determination of the reaction rate constants for lithium-lead/steam interaction. Final report 9-21-90--3-31-95  

Science Conference Proceedings (OSTI)

The objective of this research to experimentally determine the hydrogen generation rate during the beginning and subsequent stages of liquid metal (Li{sub 17}Pb{sub 83}) and water reaction. The experimental set-up has been built. It includes a metal sample preparation apparatus, a reaction system, a measurement system and a PC based data acquisition and control system. The most important feature of the reaction system is a pneumatic actuated quick opening and closing high temperature, all stainless steel valve used the system for reaction time control. The PC system provides remote process sequencing, acquisition and control of all the systems except the metal preparation apparatus. Due to the reactivity of the lithium, all the metal sampling, preparation and loading procedures are executed in a glove box under argon protection. The metal temperature was varied between 350{degrees}C-650{degrees}C and water temperature fixed at 60{degrees}C during the experiments. A set of experimental procedures and two analyses methods: (1) thermodynamics method and (2) heat transfer method are discussed. All the measurements and data collections are executed under the PC system control. A data analysis program is used to calculate both the partial pressure of hydrogen and the hydrogen generation rate. The experiment results indicate that the amount of hydrogen generated is relate to the initial liquid metal temperature when the reaction surface is fixed. The mass of hydrogen generated as a function of initial liquid metal temperature and time of reaction is presented, The hydrogen generation over a time period of 240 seconds and the calculated errors are summarized in Table 1.

Biney, P.O.

1995-03-01T23:59:59.000Z

259

Stochastic kinetic models: Dynamic independence, modularity and graphs  

E-Print Network (OSTI)

The dynamic properties and independence structure of stochastic kinetic models (SKMs) are analyzed. An SKM is a highly multivariate jump process used to model chemical reaction networks, particularly those in biochemical and cellular systems. We identify SKM subprocesses with the corresponding counting processes and propose a directed, cyclic graph (the kinetic independence graph or KIG) that encodes the local independence structure of their conditional intensities. Given a partition $[A,D,B]$ of the vertices, the graphical separation $A\\perp B|D$ in the undirected KIG has an intuitive chemical interpretation and implies that $A$ is locally independent of $B$ given $A\\cup D$. It is proved that this separation also results in global independence of the internal histories of $A$ and $B$ conditional on a history of the jumps in $D$ which, under conditions we derive, corresponds to the internal history of $D$. The results enable mathematical definition of a modularization of an SKM using its implied dynamics. Gra...

Bowsher, Clive G

2010-01-01T23:59:59.000Z

260

Simulations of Kinetic Events at the Atomic Scale  

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

of kinetic events at the atomic scale of kinetic events at the atomic scale Graeme Henkelman UT Austin Al / Al(100) B 3 I / Si Pd / MgO How can we simulate the dynamics of molecular systems over experimental time scales? Objective: To calculate dynamics of a surface over time scales which are much longer than can be calculated with direct classical dynamics. Problem: time scale gap fs ps ns ms ms s mins atomic dynamics thermally activated experimental vibrations simulations reaction dynamics time scales Most interesting transitions are rare 0.5 eV 1000/s events (much slower than vibrations) Simulating a transition for a typical rare event with classical dynamics can require ~10 12 force evaluations Transition state theory A statistical theory for calculating the rate of slow thermal processes

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


261

ESS 2012 Peer Review - Amber Kinetics Flywheel Energy Storage Demo - Ed Chiao, Amber Kinetics  

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

amber_kinetics amber_kinetics DOE Peer Review September 2012 Ed Chiao, CEO amber_kinetics Amber Kinetics: Our Flywheel History Start-up launched in 2009, Stanford University Cleantech Entrepreneurship class Established a technology licensing & flywheel development partnership with LLNL; Amber Kinetics identified new material & lower-cost rotor designs for commercialization Awarded a Smart Grid Energy Storage Demonstration grant award for flywheels Awarded a matching grant for development & demonstration of flywheel technology Stanford University Lawrence Livermore National Laboratory U.S. Department of Energy California Energy Commission World-class institutions | innovative, deep flywheel technology owned by Amber Amber Kinetics, Inc. - Confidential and Proprietary, All Rights Reserved

262

Shale oil cracking. 1. Kinetics  

DOE Green Energy (OSTI)

Experiments were conducted to determine kinetics for thermal cracking of shale oil vapor over shale. Cracking temperatures of 504 to 610/sup 0/C and residence times of 2 to 11 seconds were used. A first-order Arrhenius rate expression and stoichiometry were obtained. Also observed were changes in the oil quality. Cracking decreased the H/C ratio, increased the nitrogen content, and decreased the pour point of the oil. Gas-phase oil cracking is contrasted to liquid-phase oil coking as a loss mechanism in oil-shale retorting.

Burnham, A.K.; Taylor, J.R.

1979-10-01T23:59:59.000Z

263

Method for drilling directional wells  

Science Conference Proceedings (OSTI)

A method is described of locating a substantially horizontal bed of interest in a formation and maintaining a drill string therein during the drilling operation, said drill string including a measurement-while-drilling (MWD) electromagnetic propagation resistivity sensor, comprising the steps of: drilling a substantially vertical offset well in a formation having at least one selected substantially horizontal bed therein; measuring resistivity in the formation at the offset well to provide a first resistivity log as a function of depth; modeling the substantially horizontal bed to provide a modeled resistivity log indicative of the resistivity taken along the substantially horizontal bed, said modeling being based on said first resistivity log; drilling a directional well in said formation near said offset well, a portion of said directional well being disposed in said substantially horizontal bed; measuring resistivity in said directional well using the MWD electromagnetic propagation resistivity sensor to provide a second log of resistivity taken substantially horizontally; comparing said second log to said modeled log to determine the location of said directional well; and adjusting the directional drilling operation so as to maintain said drill string within said substantially horizontal bed during the drilling of said directional well in response to said comparing step.

Wu, Jianwu; Wisler, M.M.

1993-07-27T23:59:59.000Z

264

Measurements of Enhanced Turbulent Mixing near Highways  

Science Conference Proceedings (OSTI)

In August and September of 2010, measurements of turbulent fluxes and turbulent kinetic energy were made on highways in the Toronto area (Ontario, Canada). In situ turbulence measurements were made with a mobile laboratory while driving on the ...

Mark Gordon; Ralf M. Staebler; John Liggio; Paul Makar; Shao-Meng Li; Jeremy Wentzell; Gang Lu; Patrick Lee; Jeffrey R. Brook

2012-09-01T23:59:59.000Z

265

Nanocrystallization Reactions and Kinetics, Chemical Partitioning ...  

Science Conference Proceedings (OSTI)

Primary nanocrystallization reactions and kinetics will be discussed for selected FeCo-based ... Search of Half-Metallic Heusler Alloys and their Applications to ...

266

Aluminium Dissolution Kinetics in Caustic Media  

• Žuti?, V. and Stumm, W. (1984) Effect of organic acids and fluoride on the dissolution kinetics of hydrous alumina. A model study using the rotating disk

267

Investigating Grain Boundary Structure-Kinetic Property ...  

Science Conference Proceedings (OSTI)

Abstract Scope, Grain boundary energy landscapes contain all the information that is required to describe the kinetic behavior of grain boundaries (GBs).

268

Thermodynamic and Kinetic Simulation and Experimental Results ...  

Science Conference Proceedings (OSTI)

Through the use of thermodynamic and kinetic modeling software, NETL has designed a systematic method that has been successfully developed to design an ...

269

Experimental and Kinetic Modeling Study of Extinction and Ignition of Methyl Decanoate in Laminar Nonpremixed Flows  

DOE Green Energy (OSTI)

Methyl decanoate is a large methyl ester that can be used as a surrogate for biodiesel. In this experimental and computational study, the combustion of methyl decanoate is investigated in nonpremixed, nonuniform flows. Experiments are performed employing the counterflow configuration with a fuel stream made up of vaporized methyl decanoate and nitrogen, and an oxidizer stream of air. The mass fraction of fuel in the fuel stream is measured as a function of the strain rate at extinction, and critical conditions of ignition are measured in terms of the temperature of the oxidizer stream as a function of the strain rate. It is not possible to use a fully detailed mechanism for methyl decanoate to simulate the counterflow flames because the number of species and reactions is too large to employ with current flame codes and computer resources. Therefore a skeletal mechanism was deduced from a detailed mechanism of 8555 elementary reactions and 3036 species using 'directed relation graph' method. This skeletal mechanism has only 713 elementary reactions and 125 species. Critical conditions of ignition were calculated using this skeletal mechanism and are found to agree well with experimental data. The predicted strain rate at extinction is found to be lower than the measurements. In general, the methyl decanoate mechanism provides a realistic kinetic tool for simulation of biodiesel fuels.

Seshadri, K; Lu, T; Herbinet, O; Humer, S; Niemann, U; Pitz, W J; Law, C K

2008-01-09T23:59:59.000Z

270

Principles Governing Departmental Directives  

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

ELEMENTS FROM: SAMUEL W. BODMA 4 SUBJECT: Principles Governing Departmental Directives The Department of Energy uses directives as its primary means to establish,...

271

directed acyclic word graph  

Science Conference Proceedings (OSTI)

... and R. Verin, Direct Construction of Compact Directed Acyclic Word Graphs, 8th Annual Symposium, CPM 97, Aarhus, Denmark, 116-129, 1997. ...

2013-08-23T23:59:59.000Z

272

KINETIC STUDIES OF THE TWO LIGHT REACTIONS IN PHOTOSYNTHESIS  

SciTech Connect

The decay kinetics of the photo-induced absorbance changes in red and green algae are very sensitive to the wavelength of the actinic 11ght. A four to twofold increase in half-decay time is noted in going from short wavelength (550-650 mu) to long wavelength (> 700 mu) excitation. The slow decay ratios, produced by long wavelength light can be enhanced with a steady background of short wavelength light. A relationship between initial decay rates and 02 evolution rates is described. This relationship allows a direct correspondence between these spectroscopic studies and the 'red-drop' and 'enhancement' experiments of Emerson.

Kuntz Jr., I.D.; Calvin, Melvin

1964-11-01T23:59:59.000Z

273

Kinetic analysis of two dimensional metallic grating Cerenkov maser  

Science Conference Proceedings (OSTI)

The dispersion relation of two dimensional metallic grating Cerenkov maser has been given by using kinetic analysis, in which the influence of electron movement is directly considered without using an equivalent dielectric medium assumption. The effects of structural parameters and beam state on the interaction gain and synchronous frequency have also been investigated in detail by numerical calculations. To an illustrative case, the quantitative relations produced from varying the gap distance between electron beam and metallic grating, beam current, electron transverse to axial velocity ratio, and electron axial velocity spread have been obtained. The developed method can be used to predict the real interaction system performances.

Zhao Ding [Key Laboratory of High Power Microwave Sources and Technologies, Institute of Electronics, Chinese Academy of Sciences, Beijing 100190 (China)

2011-08-15T23:59:59.000Z

274

Velcro Measurement of Turbulence Kinetic Energy Dissipation Rate ?  

Science Conference Proceedings (OSTI)

Turbulence in the ocean results from many different processes operating over a wide range of space scales and timescales, with spatial and temporal variability particularly extreme in coastal oceans. If the origins and effects of turbulent ...

Ann E. Gargett

1999-12-01T23:59:59.000Z

275

Quantum instanton evaluation of the kinetic isotope effects  

DOE Green Energy (OSTI)

A general quantum-mechanical method for computing kinetic isotope effects is presented. The method is based on the quantum instanton approximation for the rate constant and on the path integral Metropolis Monte-Carlo evaluation of the Boltzmann operator matrix elements. It computes the kinetic isotope effect directly, using a thermodynamic integration with respect to the mass of the isotope, thus avoiding the more computationally expensive process of computing the individual rate constants. The method is more accurate than variational transition-state theories or the semiclassical instanton method since it does not assume a single reaction path and does not use a semiclassical approximation of the Boltzmann operator. While the general Monte-Carlo implementation makes the method accessible to systems with a large number of atoms, we present numerical results for the Eckart barrier and for the collinear and full three-dimensional isotope variants of the hydrogen exchange reaction H+H{sub 2} {yields} H{sub 2}+H. In all seven test cases, for temperatures between 250 K and 600 K, the error of the quantum instanton approximation for the kinetic isotope effects is less than {approx}10%.

Vanicek, Jiri; Miller, William H.; Castillo, Jesus F.; Aoiz, F.Javier

2005-04-19T23:59:59.000Z

276

ERNSTMORITZARNDTUNIVERSITAT Absolute number density and kinetic analysis  

E-Print Network (OSTI)

plasma-chemical reactions. Therefore, from the analysis of their kinetics, one can learn more about of the technical applications, many plasma­chemical processes within the discharges as well as mechanisms determines all electron induced plasma-chemical processes and hence influences the kinetics of species

Greifswald, Ernst-Moritz-Arndt-Universität

277

Kinetics of Enzymatic Depolymerization of Guar Galactomannan  

E-Print Network (OSTI)

is used as a rheology modifier in many of its applications, previous kinetic studies have been limitedKinetics of Enzymatic Depolymerization of Guar Galactomannan Shamsheer Mahammad, Robert K. Prud'homme, George W. Roberts,*, and Saad A. Khan*, Department of Chemical and Biomolecular Engineering, North

Khan, Saad A.

278

Chemical kinetics and oil shale process design  

SciTech Connect

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.

Burnham, A.K.

1993-07-01T23:59:59.000Z

279

Direct process for explosives  

SciTech Connect

A direct process of making ethylenediamine dinitrate through the reaction of ethylenediamine and ammonium nitrate.

Akst, Irving B. (1032 Duncan St., Pampa, TX 79065); Stinecipher, Mary M. (324 Connie St., Los Alamos, NM 87544)

1982-01-01T23:59:59.000Z

280

Kinetic advantage of controlled intermediate nuclear fusion  

SciTech Connect

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.

Guo Xiaoming [Physics and Computer Science Department, Wilfrid Laurier University, Waterloo, Ontario, N2L 3C5 (Canada)

2012-09-26T23:59:59.000Z

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


281

Foreign Direct Investment  

Gasoline and Diesel Fuel Update (EIA)

Investment Investment Foreign Direct Investment Foreign Direct Investment Foreign Direct Investment in U.S. Energy in U.S. Energy in U.S. Energy in U.S. Energy in 1999 in 1999 in 1999 in 1999 June 2001 ii iii Contents Foreign Affiliates' Role in U.S. Energy Industry Operations ..............................................................................1 Foreign Direct Investment: The International Transactions Accounts ..............................................................8 U.S. Companies' Direct Investment Abroad in Energy ......................................................................................14 Conclusion...............................................................................................................................................................19

282

Conformational Analysis of ET Kinetics across Oligoproline Peptides  

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

Analysis of the Electron-Transfer Kinetics across Analysis of the Electron-Transfer Kinetics across Oligoproline Peptides Using N,N-Dimethyl-1,4-benzenediamine Donors and Pyrene-1-sulfonyl Acceptors Joseph B. Issa, Abdu S. Salameh, Edward W. Castner, Jr., James F. Wishart, and Stephan S. Isied J. Phys. Chem. B 111, 6878-6886 (2007). [Find paper at ACS Publications] or use ACS Articles on Request Abstract: Photoinduced intramolecular charge separation across proline-bridged donor-acceptor complexes of the type Pyr-(Pro)n-DMPD (where Pyr = pyrene-1-sulfonyl and DMPD = N,N-dimethyl-1,4-phenylenediamine) was studied. The steady-state emission spectrum for n = 0, 1, 2, 3 showed an increase in emission intensity with the number of proline residues. Time-dependent emission measured by streak camera showed increasing

283

An Independent Derivation of the Oxford Jet Kinetic Luminosity Formula  

E-Print Network (OSTI)

This letter presents a theoretical derivation of an estimate for a radio source jet kinetic luminosity. The expression yields jet powers that are quantitatively similar to a more sophisticated empirical relation published by the Willott, Blundell and Rawlings at Oxford. The formula allows one to estimate the jet kinetic luminosity from the measurement of the optically thin radio lobe emission in quasars and radio galaxies. Motivated by recent X-ray observation, the derivation assumes that most of the energy in the lobes is in plasma thermal energy with a negligible contribution from magnetic energy (not equipartition). The close agreement of the two independent expressions makes the veracity of these estimates seem very plausible.

Brian Punsly

2005-03-11T23:59:59.000Z

284

Reservoir Management in Mediterranean Climates through the European Water Framework Directive  

E-Print Network (OSTI)

the EuropeanWater Framework Directive? ” Elsevier Cabecinha,Under the Water Framework Directive. Conacher, A.J. , Sala,The EU Water Framework Directive: measures and implications.

O'Reilly, Clare; Silberblatt, Rafael

2009-01-01T23:59:59.000Z

285

Model simplification of chemical kinetic systems under uncertainty  

E-Print Network (OSTI)

This thesis investigates the impact of uncertainty on the reduction and simplification of chemical kinetics mechanisms. Chemical kinetics simulations of complex fuels are very computationally expensive, especially when ...

Coles, Thomas Michael Kyte

2011-01-01T23:59:59.000Z

286

HIGH PRESSURE COAL COMBUSTON KINETICS PROJECT  

SciTech Connect

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 mechanism for the NBFZ tests.

Stefano Orsino

2005-03-30T23:59:59.000Z

287

Recent Advances in Detailed Chemical Kinetic Models for Large Hydrocarbon and Biodiesel Transportation Fuels  

DOE Green Energy (OSTI)

n-Hexadecane and 2,2,4,4,6,8,8-heptamethylnonane represent the primary reference fuels for diesel that are used to determine cetane number, a measure of the ignition property of diesel fuel. With the development of chemical kinetics models for these two primary reference fuels for diesel, a new capability is now available to model diesel fuel ignition. Also, we have developed chemical kinetic models for a whole series of large n-alkanes and a large iso-alkane to represent these chemical classes in fuel surrogates for conventional and future fuels. Methyl decanoate and methyl stearate are large methyl esters that are closely related to biodiesel fuels, and kinetic models for these molecules have also been developed. These chemical kinetic models are used to predict the effect of the fuel molecule size and structure on ignition characteristics under conditions found in internal combustion engines.

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

2009-03-30T23:59:59.000Z

288

Modeling of Reactor Kinetics and Dynamics  

SciTech Connect

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.

Matthew Johnson; Scott Lucas; Pavel Tsvetkov

2010-09-01T23:59:59.000Z

289

Direct Loan Program (Connecticut)  

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

The Connecticut Development Authority’s Direct Loan Program provides direct senior and subordinated loans and mezzanine investments to companies creating or maintaining jobs. Up to $20,000 per job...

290

Direct process for explosives  

DOE Patents (OSTI)

A direct process of making ethylenediamine dinitrate through the reaction of ethylenediamine and ammonium nitrate is described.

Akst, I.B.; Stinecipher, M.M.

1982-10-12T23:59:59.000Z

291

Kinetic Energy LLC | Open Energy Information  

Open Energy Info (EERE)

Name Kinetic Energy LLC Place Texas Utility Id 56210 Utility Location Yes Ownership R NERC ERCOT Yes ISO Ercot Yes Activity Retail Marketing Yes References EIA Form EIA-861...

292

AER NY Kinetics LLC | Open Energy Information  

Open Energy Info (EERE)

Database. This company is involved in the following MHK Projects: Ogdensburg Kinetic Energy Project This article is a stub. You can help OpenEI by expanding it. Retrieved...

293

Kinetic Energy and the Equivalence Principle  

E-Print Network (OSTI)

According to the general theory of relativity, kinetic energy contributes to gravitational mass. Surprisingly, the observational evidence for this prediction does not seem to be discussed in the literature. I reanalyze existing experimental data to test the equivalence principle for the kinetic energy of atomic electrons, and show that fairly strong limits on possible violations can be obtained. I discuss the relationship of this result to the occasional claim that ``light falls with twice the acceleration of ordinary matter.''

S. Carlip

1999-09-03T23:59:59.000Z

294

Bench-scale Kinetics Study of Mercury Reactions in FGD Liquors  

SciTech Connect

This document is the final report for Cooperative Agreement DE-FC26-04NT42314, 'Kinetics Study of Mercury Reactions in FGD Liquors'. The project was co-funded by the U.S. DOE National Energy Technology Laboratory and EPRI. The objective of the project has been to determine the mechanisms and kinetics of the aqueous reactions of mercury absorbed by wet flue gas desulfurization (FGD) systems, and develop a kinetics model to predict mercury reactions in wet FGD systems. The model may be used to determine optimum wet FGD design and operating conditions to maximize mercury capture in wet FGD systems. Initially, a series of bench-top, liquid-phase reactor tests were conducted and mercury species concentrations were measured by UV/visible light spectroscopy to determine reactant and byproduct concentrations over time. Other measurement methods, such as atomic absorption, were used to measure concentrations of vapor-phase elemental mercury, that cannot be measured by UV/visible light spectroscopy. Next, a series of bench-scale wet FGD simulation tests were conducted. Because of the significant effects of sulfite concentration on mercury re-emission rates, new methods were developed for operating and controlling the bench-scale FGD experiments. Approximately 140 bench-scale wet FGD tests were conducted and several unusual and pertinent effects of process chemistry on mercury re-emissions were identified and characterized. These data have been used to develop an empirically adjusted, theoretically based kinetics model to predict mercury species reactions in wet FGD systems. The model has been verified in tests conducted with the bench-scale wet FGD system, where both gas-phase and liquid-phase mercury concentrations were measured to determine if the model accurately predicts the tendency for mercury re-emissions. This report presents and discusses results from the initial laboratory kinetics measurements, the bench-scale wet FGD tests, and the kinetics modeling efforts.

Gary Blythe; John Currie; David DeBerry

2008-03-31T23:59:59.000Z

295

A general kinetic model: Kinetics and atomic-scale mechanisms of feldspar dissolution.  

E-Print Network (OSTI)

??This thesis presents a general kinetic model and its application to feldspar dissolution. In the framework of Monte Carlo methods, the model simulates the stochastic… (more)

Zhang, Li

2008-01-01T23:59:59.000Z

296

The Multiplexed Chemical Kinetic Photoionization Mass Spectrometer: A New Approach To Isomer-resolved Chemical Kinetics  

E-Print Network (OSTI)

instruments applied to analysis of complex chemical mixturesrelies on chemical separation (by chromatography) into pureThe multiplexed chemical kinetic photoionization mass

Osborne, David L.

2009-01-01T23:59:59.000Z

297

Kinetic Theory of Plasma Waves - Part III: Inhomogeneous Plasma  

Science Conference Proceedings (OSTI)

Kinetic Theory / Proceedings of the Ninth Carolus Magnus Summer School on Plasma and Fusion Energy Physics

P. U. Lamalle

298

Kinetic Theory of Plasma Waves - Part I: Introduction  

Science Conference Proceedings (OSTI)

Kinetic Theory / Proceedings of the Ninth Carolus Magnus Summer School on Plasma and Fusion Energy Physics

P. U. Lamalle

299

Bio-butanol: Combustion properties and detailed chemical kinetic model  

Science Conference Proceedings (OSTI)

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)

Black, G.; Curran, H.J.; Pichon, S.; Simmie, J.M.; Zhukov, V. [Combustion Chemistry Centre, National University of Ireland, Galway (Ireland)

2010-02-15T23:59:59.000Z

300

Particle Impact and Breakup in Aircraft Measurement  

Science Conference Proceedings (OSTI)

Measurements of cloud particle properties from aircraft by optical and impact techniques are subject to artifacts following particle breakup prior to detection. The impact kinetic energy to surface energy ratio (L) provides a breakup criterion at ...

German Vidaurre; John Hallett

2009-05-01T23:59:59.000Z

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


301

Kinetic instability of drift-Alfven waves in solar corona and stochastic heating  

E-Print Network (OSTI)

The solar atmosphere is structured and inhomogeneous both horizontally and vertically. The omnipresence of coronal magnetic loops implies gradients of the equilibrium plasma quantities like the density, magnetic field and temperature. These gradients are responsible for the excitation of drift waves that grow both within the two-component fluid description (in the presence of collisions and without it) and within the two-component kinetic descriptions (due to purely kinetic effects). In the present work the effects of the density gradient in the direction perpendicular to the magnetic field vector are investigated within the kinetic theory, in both electrostatic and electromagnetic regimes. The electromagnetic regime implies the coupling of the gradient-driven drift wave with the Alfven wave. The growth rates for the two cases are calculated and compared. It is found that, in general, the electrostatic regime is characterized by stronger growth rates, as compared with the electromagnetic perturbations. Also d...

Vranjes, J

2010-01-01T23:59:59.000Z

302

Direct energy conversion systems  

SciTech Connect

The potential importance of direct energy conversion to the long-term development of fusion power is discussed with stress on the possibility of alleviating waste heat problems. This is envisioned to be crucial for any central power station in the 21st century. Two approaches to direct conversion, i.e., direct collection and magnetic expansion, are reviewed. While other techniques may be possible, none have received sufficient study to allow evaluation. It is stressed that, due to the intimate connection between the type of fusion fuel, the confinement scheme, direct conversion, and the coupling technique, all four element must be optimized simultaneously for high overall efficiency.

Miley, G.H.

1978-01-01T23:59:59.000Z

303

A Multiple Direction Radiation Sensor, DIRAM  

Science Conference Proceedings (OSTI)

The Directional Radiance Distribution Measurement (DIRAM) device was designed and built to determine the angular distribution of shortwave radiance as a function of height in cloudy and clear-sky conditions at various surface albedos. The ...

J. C. H. van der Hage; H. van Dop; A. Los; W. Boot; D. van As

2001-12-01T23:59:59.000Z

304

Pseudo-isothermal ice-crystallization kinetics in the gas-diffusion layer  

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

Pseudo-isothermal ice-crystallization kinetics in the gas-diffusion layer Pseudo-isothermal ice-crystallization kinetics in the gas-diffusion layer of a fuel cell from differential scanning calorimetry Title Pseudo-isothermal ice-crystallization kinetics in the gas-diffusion layer of a fuel cell from differential scanning calorimetry Publication Type Journal Article Year of Publication 2013 Authors Dursch, Thomas J., Monica A. Ciontea, Gregory J. Trigub, Clayton J. Radke, and Adam Z. Weber Journal International Journal of Heat and Mass Transfer Volume 60 Pagination 450 - 458 Date Published 5/2013 ISSN 00179310 Keywords crystallization, differential scanning calorimetry, gas-diffusion layer, Heat Transfer, kinetics, melt, nonisothermal crystallization, nucleation, polyesters, polymer crystallization, solidification Abstract Non-isothermal ice-crystallization kinetics in the fibrous gas-diffusion layer (GDL) of a proton-exchange-membrane fuel cell is investigated using differential scanning calorimetry (DSC). Non-isothermal ice-crystallization rates and ice-crystallization temperatures are obtained from heat-flow measurements in a water-saturated commercial GDL at cooling rates of 2.5, 5, 10, and 25 K/min. Our previously developed isothermal ice-crystallization rate expression is extended to non-isothermal crystallization to predict ice-crystallization kinetics in a GDL at various cooling rates. Agreement between DSC experimental results and theory is good. Both show that as the cooling rate increases, ice-crystallization rates increase and crystallization temperatures decrease monotonically. Importantly, we find that the cooling rate during crystallization has a negligible effect on the crystallization rate when crystallization times are much faster than the time to decrease the sample temperature by the subcooling. Based on this finding, we propose a pseudo-isothermal method for obtaining non-isothermal crystallization kinetics using isothermal crystallization kinetics evaluated at the non-isothermal crystallization temperature.

305

Heat Transfer Analysis and Assessment of Kinetics Systems for PBX 9501  

SciTech Connect

The study of thermal decomposition in high explosive (HE) charges has been an ongoing process since the early 1900s. This work is specifically directed towards the analysis of PBX 9501. In the early 1970s, Dwight Jaeger of Los Alamos National Laboratory (LANL) developed a single-step, two-species kinetics system that was used in the development of one of the first finite element codes for thermal analyses known as EXPLO. Jaeger's research focused on unconfined spherical samples of HE charges to determine if varied heating ramps would cause detonation or deflagration. Tarver and McGuire of Lawrence Livermore National Laboratory (LLNL) followed soon after with a three-step, four-species kinetics system that was developed for confined spheres under relatively fast heating conditions. Peter Dickson et al. of LANL then introduced a kinetics system with four steps and five species that included bimolecular products to capture the effects of the endothermic phase change that the HE undergoes. The results of four experiments are examined to study the effectiveness of these kinetics systems. The experiments are: (1) The LLNL scaled thermal explosion (STEX) experiments on confined cylindrical charges with long heating ramps in the range of 90 hours. (2) The LLNL one-dimensional time to explosion (ODTX) experiments on spherical charges that include confined, partially confined, and aged HE experiments. (3) The LANL unconfined one-dimensional experiments for small spheres. (4) The Naval Air Warfare Center Weapons Division at China Lake experiments on small confined cylinders. The three kinetics systems are applied to each of the four experiments with the use of the finite element analysis (FEA) heat conduction solver COYOTE. The numerical results using the kinetics systems are compared to each other and to the experimental data to determine which kinetics systems are best suited for analyzing conditions such as time to ignition, containment, heating time, and location of ignition.

Jeffrey W. Jorenby

2006-07-31T23:59:59.000Z

306

Multiple temperature kinetic model and gas-kinetic method for hypersonic non-equilibrium flow computations  

Science Conference Proceedings (OSTI)

It is well known that for increasingly rarefied flowfields, the predictions from continuum formulation, such as the Navier-Stokes equations lose accuracy. For the high speed diatomic molecular flow in the transitional regime, the inaccuracies are partially ... Keywords: Gas-kinetic method, Hypersonic and rarefied flows, Multiple temperature kinetic model

Kun Xu; Xin He; Chunpei Cai

2008-07-01T23:59:59.000Z

307

Assessment report on the kinetics of radionuclide adsorption on Yucca Mountain tuff  

SciTech Connect

The kinetics of sorption was measured by observing the uptake of radionuclides by tuff wafers and crushed tuff as a function of time. In addition, the broadening of breakthrough curves for cations eluted through crushed-tuff columns was interpreted in terms of adsorption kinetics. The results of these measurements are consistent with a diffusion-limited adsorption mechanism for simple cations, such as strontium, cesium, and barium. The adsorption kinetics for these simple cations is sufficiently fast so that equilibrium can be assumed for the retardation of these chemical species in the groundwater velocities that would be reasonable for most release scenarios. The actinides, in particular plutonium, exhibited a slow time dependence for adsorption. 23 refs., 61 figs., 12 tabs.

Rundberg, R.S.

1987-07-01T23:59:59.000Z

308

Alfvenic Turbulence in the Extended Solar Corona: Kinetic Effects and Proton Heating  

E-Print Network (OSTI)

We present a model of magnetohydrodynamic (MHD) turbulence in the extended solar corona that contains the effects of collisionless dissipation and anisotropic particle heating. Measurements made by UVCS/SOHO have revived interest in the idea that ions are energized by the dissipation of ion cyclotron resonant waves, but such high-frequency (i.e., small wavelength) fluctuations have not been observed. A turbulent cascade is one possible way of generating small-scale fluctuations from a pre-existing population of low-frequency MHD waves. We model this cascade as a combination of advection and diffusion in wavenumber space. The dominant spectral transfer occurs in the direction perpendicular to the background magnetic field. As expected from earlier models, this leads to a highly anisotropic fluctuation spectrum with a rapidly decaying tail in parallel wavenumber. The wave power that decays to high enough frequencies to become ion cyclotron resonant depends on the relative strengths of advection and diffusion in the cascade. For the most realistic values of these parameters, though, there is insufficient power to heat protons and heavy ions. The dominant oblique fluctuations (with dispersion properties of kinetic Alfven waves) undergo Landau damping, which implies strong parallel electron heating. We discuss the probable nonlinear evolution of the electron velocity distributions into parallel beams and discrete phase-space holes (similar to those seen in the terrestrial magnetosphere) which can possibly heat protons via stochastic interactions.

S. R. Cranmer; A. A. van Ballegooijen

2003-05-08T23:59:59.000Z

309

Position and energy-resolved particle detection using phonon-mediated microwave kinetic inductance detectors  

Science Conference Proceedings (OSTI)

We demonstrate position and energy-resolved phonon-mediated detection of particle interactions in a silicon substrate instrumented with an array of microwave kinetic inductance detectors (MKIDs). The relative magnitude and delay of the signal received in each sensor allow the location of the interaction to be determined with < or approx. 1mm resolution at 30 keV. Using this position information, variations in the detector response with position can be removed, and an energy resolution of {sigma}{sub E} = 0.55 keV at 30 keV was measured. Since MKIDs can be fabricated from a single deposited film and are naturally multiplexed in the frequency domain, this technology can be extended to provide highly pixelized athermal phonon sensors for {approx}1 kg scale detector elements. Such high-resolution, massive particle detectors would be applicable to rare-event searches such as the direct detection of dark matter, neutrinoless double-beta decay, or coherent neutrino-nucleus scattering.

Moore, D. C.; Golwala, S. R.; Cornell, B. [Division of Physics, Mathematics and Astronomy, California Institute of Technology, Pasadena, California 91125 (United States); Bumble, B.; Day, P. K.; LeDuc, H. G. [Jet Propulsion Laboratory, California Institute of Technology, Pasadena, California 91109 (United States); Zmuidzinas, J. [Division of Physics, Mathematics and Astronomy, California Institute of Technology, Pasadena, California 91125 (United States); Jet Propulsion Laboratory, California Institute of Technology, Pasadena, California 91109 (United States)

2012-06-04T23:59:59.000Z

310

Chemical Kinetic Modeling of Advanced Transportation Fuels  

DOE Green Energy (OSTI)

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.

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

2009-01-20T23:59:59.000Z

311

direct_deposit_111609  

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

PROTECT YOUR BANKING INFORMATION: PROTECT YOUR BANKING INFORMATION: DO NOT complete this form until you are ready to submit it to the Payroll Department. DIRECT DEPOSIT REQUEST Directions: 1. Provide required information neatly, legibly; 2. If Checking Account Direct Deposit, include a voided check. a. DO NOT submit a deposit slip! 3. If Savings Account Direct Deposit, include a copy of savings card. 4. Sign this form; 5. Inter-office mail it to Craft Payroll at "P238." DIRECT DEPOSITION AUTHORIZATION I hereby authorize Los Alamos National Laboratory, hereinafter called The Laboratory, to initiate credit entries and, if necessary, debit entries and adjustments for any credit entries in error to my account listed on this form. If deposit is for:

312

Directions and Maps  

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

Directions & Maps Directions & Maps Plan Your Visit Visit About the Museum Museum Hours Directions & Maps When to Visit Arrange for a Visit Around Los Alamos Contact Us invisible utility element Directions and Maps Aerial View of Los Alamos Aerial approach to the Los Alamos airport Where we're located Los Alamos (elevation 7,355 feet) is perched high atop the Pajarito Plateau in the Jemez Mountains, 35 miles northwest of Santa Fe. The Bradbury Science Museum is located in downtown Los Alamos at the corner of Central Avenue and 15th Street. If you're driving here and using GPS navigation, our address is 1350 Central Avenue, Los Alamos, NM 87544. How to get here From Albuquerque take I-25 north to Santa Fe (take NM 599 for most direct route), then US 84/285 north to Pojoaque. At Pojoaque take the NM 502 exit

313

THERMOCHEMICAL AND PHOTOCHEMICAL KINETICS IN COOLER HYDROGEN-DOMINATED EXTRASOLAR PLANETS: A METHANE-POOR GJ436b?  

Science Conference Proceedings (OSTI)

We introduce a thermochemical kinetics and photochemical model. We use high-temperature bidirectional reaction rates for important H, C, O, and N reactions (most importantly for CH{sub 4} to CO interconversion), allowing us to attain thermochemical equilibrium, deep in an atmosphere, purely kinetically. This allows the chemical modeling of an entire atmosphere, from deep-atmosphere thermochemical equilibrium to the photochemically dominated regime. We use our model to explore the atmospheric chemistry of cooler (T{sub eff} < 10{sup 3} K) extrasolar giant planets. In particular, we choose to model the nearby hot-Neptune GJ436b, the only planet in this temperature regime for which spectroscopic measurements and estimates of chemical abundances now exist. Recent Spitzer measurements with retrieval have shown that methane is driven strongly out of equilibrium and is deeply depleted on the day side of GJ436b, whereas quenched carbon monoxide is abundant. This is surprising because GJ436b is cooler than many of the heavily irradiated hot Jovians and thermally favorable for CH{sub 4}, and thus requires an efficient mechanism for destroying it. We include realistic estimates of ultraviolet flux from the parent dM star GJ436, to bound the direct photolysis and photosensitized depletion of CH{sub 4}. While our models indicate fairly rich disequilibrium conditions are likely in cooler exoplanets over a range of planetary metallicities, we are unable to generate the conditions for substantial CH{sub 4} destruction. One possibility is an anomalous source of abundant H atoms between 0.01 and 1 bars (which attack CH{sub 4}), but we cannot as yet identify an efficient means to produce these hot atoms.

Line, Michael R.; Yung, Yuk L. [California Institute of Technology, Pasadena, CA 91106 (United States); Vasisht, Gautam; Chen, Pin [Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109 (United States); Angerhausen, D., E-mail: mrl@gps.caltech.edu, E-mail: gv@s383.jpl.nasa.gov [Hamburger Sternwarte, Universitaet Hamburg, 21029 Hamburg (Germany)

2011-09-01T23:59:59.000Z

314

Direct Estimation of Heat Flux in a Seasonal Thermocline  

Science Conference Proceedings (OSTI)

This paper reports on a direct measurement of the turbulent heat flux. The sampling was from a submarine that used a conventional airfoil probe to measure the vertical component of turbulent velocity and a thermistor probe to measure the ...

Hidekatsu Yamazaki; Thomas Osborn

1993-03-01T23:59:59.000Z

315

Philips Color Kinetics | Open Energy Information  

Open Energy Info (EERE)

Color Kinetics Color Kinetics Jump to: navigation, search Name Philips Color Kinetics Address 3 Burlington Woods Drive, 4th Floor Place Burlington, Massachusetts Zip 01803 Sector Efficiency Product LED lighting systems Website http://www.colorkinetics.com/ Coordinates 42.5005723°, -71.2042619° Loading map... {"minzoom":false,"mappingservice":"googlemaps3","type":"ROADMAP","zoom":14,"types":["ROADMAP","SATELLITE","HYBRID","TERRAIN"],"geoservice":"google","maxzoom":false,"width":"600px","height":"350px","centre":false,"title":"","label":"","icon":"","visitedicon":"","lines":[],"polygons":[],"circles":[],"rectangles":[],"copycoords":false,"static":false,"wmsoverlay":"","layers":[],"controls":["pan","zoom","type","scale","streetview"],"zoomstyle":"DEFAULT","typestyle":"DEFAULT","autoinfowindows":false,"kml":[],"gkml":[],"fusiontables":[],"resizable":false,"tilt":0,"kmlrezoom":false,"poi":true,"imageoverlays":[],"markercluster":false,"searchmarkers":"","locations":[{"text":"","title":"","link":null,"lat":42.5005723,"lon":-71.2042619,"alt":0,"address":"","icon":"","group":"","inlineLabel":"","visitedicon":""}]}

316

Chemical kinetic modelling of hydrocarbon ignition  

DOE Green Energy (OSTI)

Chemical kinetic modeling of hydrocarbon ignition is discussed with reference to a range of experimental configurations, including shock tubes, detonations, pulse combustors, static reactors, stirred reactors and internal combustion engines. Important conditions of temperature, pressure or other factors are examined to determine the main chemical reaction sequences responsible for chain branching and ignition, and kinetic factors which can alter the rate of ignition are identified. Hydrocarbon ignition usually involves complex interactions between physical and chemical factors, and it therefore is a suitable and often productive subject for computer simulations. In most of the studies to be discussed below, the focus of the attention is placed on the chemical features of the system. The other physical parts of each application are generally included in the form of initial or boundary conditions to the chemical kinetic parts of the problem, as appropriate for each type of application being addressed.

Westbrook, C.K.; Pitz, W.J.; Curran, H.J.; Gaffuri, P.; Marinov, N.M.

1995-08-25T23:59:59.000Z

317

Wellbore inertial directional surveying system  

DOE Patents (OSTI)

A wellbore inertial directional surveying system for providing a complete directional survey of an oil or gas well borehole to determine the displacement in all three directions of the borehole path relative to the well head at the surface. The information generated by the present invention is especially useful when numerous wells are drilled to different geographical targets from a single offshore platform. Accurate knowledge of the path of the borehole allows proper well spacing and provides assurance that target formations are reached. The tool is lowered down into a borehole on an electrical cable. A computer positioned on the surface communicates with the tool via the cable. The tool contains a sensor block which is supported on a single gimbal, the rotation axis of which is aligned with the cylinder axis of the tool and, correspondingly, the borehole. The gyroscope measurement of the sensor block rotation is used in a null-seeking servo loop which essentially prevents rotation of the sensor block about the gimbal axis. Angular rates of the sensor block about axes which are perpendicular to te gimbal axis are measured by gyroscopes in a manner similar to a strapped-down arrangement. Three accelerometers provide acceleration information as the tool is lowered within the borehole. The uphole computer derives position information based upon acceleration information and angular rate information. Kalman estimation techniques are used to compensate for system errors. 25 figures.

Andreas, R.D.; Heck, G.M.; Kohler, S.M.; Watts, A.C.

1982-09-08T23:59:59.000Z

318

Wellbore inertial directional surveying system  

DOE Patents (OSTI)

A wellbore inertial directional surveying system for providing a complete directional survey of an oil or gas well borehole to determine the displacement in all three directions of the borehole path relative to the well head at the surface. The information generated by the present invention is especially useful when numerous wells are drilled to different geographical targets from a single off-shore platform. Accurate knowledge of the path of the borehole allows proper well spacing and provides assurance that target formations are reached. The tool is lowered down into a borehole on the electrical cable. A computer positioned on the surface communicates with the tool via the cable. The tool contains a sensor block which is supported on a single gimbal, the rotation axis of which is aligned with the cylinder axis of the tool and, correspondingly, the borehole. The gyroscope measurement of the sensor block rotation is used in a null-seeking servo loop which essentially prevents rotation of the sensor block aboutthe gimbal axis. Angular rates of the sensor block about axes which are perpendicular to the gimbal axis are measured by gyroscopes in a manner similar to a strapped-down arrangement. Three accelerometers provide acceleration information as the tool is lowered within the borehole. The uphole computer derives position information based upon acceleration information and anular rate information. Kalman estimation techniques are used to compensate for system errors.

Andreas, Ronald D. (Albuquerque, NM); Heck, G. Michael (Albuquerque, NM); Kohler, Stewart M. (Albuquerque, NM); Watts, Alfred C. (Albuquerque, NM)

1991-01-01T23:59:59.000Z

319

Ionization based multi-directional flow sensor  

SciTech Connect

A method, system, and apparatus for conducting real-time monitoring of flow (airflow for example) in a system (a hybrid power generation system for example) is disclosed. The method, system and apparatus measure at least flow direction and velocity with minimal pressure drop and fast response. The apparatus comprises an ion source and a multi-directional collection device proximate the ion source. The ion source is configured to generate charged species (electrons and ions for example). The multi-directional collection source is configured to determine the direction and velocity of the flow in real-time.

Chorpening, Benjamin T. (Morgantown, WV); Casleton, Kent H. (Morgantown, WV)

2009-04-28T23:59:59.000Z

320

Model Independent Bounds on Kinetic Mixing  

SciTech Connect

New Abelian vector bosons can kinetically mix with the hypercharge gauge boson of the Standard Model. This letter computes the model independent limits on vector bosons with masses from 1 GeV to 1 TeV. The limits arise from the numerous e{sup +}e{sup -} experiments that have been performed in this energy range and bound the kinetic mixing by {epsilon} {approx}< 0.03 for most of the mass range studied, regardless of any additional interactions that the new vector boson may have.

Hook, Anson; Izaguirre, Eder; Wacker, Jay G.; /SLAC

2011-08-22T23:59:59.000Z

Note: This page contains sample records for the topic "direct kinetic measurements" from the National Library of EnergyBeta (NLEBeta).
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they are not comprehensive nor are they the most current set.
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321

Chemical Dynamics, Molecular Energetics, and Kinetics at the Synchrotron  

SciTech Connect

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.

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

2010-03-14T23:59:59.000Z

322

An Experimental and Kinetic Modeling Study of Methyl Decanoate Combustion  

DOE Green Energy (OSTI)

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.

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

2010-02-19T23:59:59.000Z

323

Surface Wind Direction Variability  

Science Conference Proceedings (OSTI)

Common large shifts of wind direction in the weak-wind nocturnal boundary layer are poorly understood and are not adequately captured by numerical models and statistical parameterizations. The current study examines 15 datasets representing a ...

Larry Mahrt

2011-01-01T23:59:59.000Z

324

2013 FCMN Directions  

Science Conference Proceedings (OSTI)

... $100 (one way). Driving directions: Take I-95S to Exit 4B towards Washington.Merge onto I-495 to Exit 27 towards Silver Spring.Slight right onto ...

2013-02-27T23:59:59.000Z

325

Direct nuclear pumped laser  

DOE Patents (OSTI)

There is provided a direct nuclear pumped gas laser in which the lasing mechanism is collisional radiated recombination of ions. The gas laser active medium is a mixture of the gases, with one example being neon and nitrogen.

Miley, George H. (Champagne, IL); Wells, William E. (Urbana, IL); DeYoung, Russell J. (Hampton, VA)

1978-01-01T23:59:59.000Z

326

Maps & Directions | ORNL  

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

Maps & Directions ORNL is located in Roane County, Tennessee, about 7 miles from the center of the city of Oak Ridge and about 25 miles from the McGhee Tyson Airport near...

327

Refrigerant directly cooled capacitors  

DOE Patents (OSTI)

The invention is a direct contact refrigerant cooling system using a refrigerant floating loop having a refrigerant and refrigeration devices. The cooling system has at least one hermetic container disposed in the refrigerant floating loop. The hermetic container has at least one electronic component selected from the group consisting of capacitors, power electronic switches and gating signal module. The refrigerant is in direct contact with the electronic component.

Hsu, John S. (Oak Ridge, TN); Seiber, Larry E. (Oak Ridge, TN); Marlino, Laura D. (Oak Ridge, TN); Ayers, Curtis W. (Kingston, TN)

2007-09-11T23:59:59.000Z

328

Kinetic Model Development for the Combustion of Particulate Matter from Conventional and Soy Methyl Ester Diesel Fuels  

DOE Green Energy (OSTI)

The primary objective of this research has been to investigate how the oxidation characteristics of diesel particulate matter (PM) are affected by blending soy-based biodiesel fuel with conventional ultra low sulfur diesel (ULSD) fuel. PM produced in a light duty engine from different biodiesel-conventional fuel blends was subjected to a range of physical and chemical measurements in order to better understand the mechanisms by which fuel-related changes to oxidation reactivity are brought about. These observations were then incorporated into a kinetic model to predict PM oxidation. Nanostructure of the fixed carbon was investigated by HR-TEM and showed that particulates from biodiesel had a more open structure than particulates generated from conventional diesel fuel, which was confirmed by BET surface area measurements. Surface area evolution with extent of oxidation reaction was measured for PM from ULSD and biodiesel. Biodiesel particulate has a significantly larger surface area for the first 40% of conversion, at which point the samples become quite similar. Oxidation characteristics of nascent PM and the fixed carbon portion were measured by temperature programmed oxidation (TPO) and it was noted that increased biodiesel blending lowered the light-off temperature as well as the temperature where the peak rate of oxidation occurred. A shift in the oxidation profiles of all fuels was seen when the mobile carbon fraction was removed, leaving only the fixed carbon, however the trend in temperature advantage of the biofuel blending remained. The mobile carbon fraction was measured by temperature programmed desorption found to generally increase with increasing biodiesel blend level. The relative change in the light-off temperatures for the nascent and fixed carbon samples was found to be related to the fraction of mobile carbon. Effective Arrhenius parameters for fixed carbon oxidation were directly measured with isothermal, differential oxidation experiments. Normalizing the reaction rate to the total carbon surface area available for reaction allowed for the definition of a single reaction rate with constant activation energy (112.5 {+-} 5.8 kJ/mol) for the oxidation of PM, independent of its fuel source. A kinetic model incorporating the surface area dependence of fixed carbon oxidation rate and the impact of the mobile carbon fraction was constructed and validated against experimental data.

Strzelec, Andrea [ORNL

2009-12-01T23:59:59.000Z

329

Outline Development of Direct PCR Benefits of Direct PCR ...  

Science Conference Proceedings (OSTI)

... 1 Direct PCR Amplification of STR Loci: Protocols and Performance ... Benefits of direct PCR • Collection media: FTA and 903 paper ...

2011-05-31T23:59:59.000Z

330

Solids decomposition kinetics for LASL bismuth sulfate cycle  

DOE Green Energy (OSTI)

The LASL Bismuth Sulfate Cycle includes a solid-decomposition step as an alternative to the high-temperature evaporation and decomposition of concentrated sulfuric acid, with its attendant drying and materials problems. A solids decomposition facility was constructed and used to study the handling of solid sulfates and the kinetics of their decomposition. The decomposition of Bi/sub 2/O(SO/sub 4/)/sub 2/ has been measured as a function of temperature and transit time through a laboratory-scale rotary kiln, constructed from quartz. Temperatures from 973 to 1143/sup 0/K were investigated. The transit time was controlled by varying the slope of the kiln, its rotational speed, and the rate of feed of a bismuth oxysulfate prepared in the prescribed manner. The preparation and characterization of this solid, which has reasonable feeding properties and minimal solution retention, are described. Significant amounts of decomposition were measured in short reaction times at the temperatures investigated.

Peterson, C.L.; Bowman, M.G.

1980-01-01T23:59:59.000Z

331

Kinetics of the Direct Causticizing Reaction between Black Liquor and Titanates During Low Temperature Gasification.  

E-Print Network (OSTI)

??Gasification of kraft black liquor increases the amount of Na2CO3, which needs to be converted into NaOH in the lune cycle because one mole of… (more)

Chen, Xiaowen

2005-01-01T23:59:59.000Z

332

Isopiestic Kinetics of Powdered Pd/C/DPB Composite  

DOE Green Energy (OSTI)

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 centers on the development of an understanding of the kinetics for the hydrogenation of DPB and DEB as a function of temperature and pressure.

Dinh, L; Saab, A

2008-05-30T23:59:59.000Z

333

Kinetics of simultaneous two-phase precipitation in the Fe-C system  

Science Conference Proceedings (OSTI)

A theoretical approach for the interpretation of the kinetics of simultaneous stable and metastable phase precipitation in a binary system is proposed. The model, based on the nucleation and growth theory, defines a critical size different for each phase. The size of the clusters evolves by adding or subtracting a single atom one at a time. A set of coupled differential equations is obtained for the chemical rate whose solution reproduces the kinetics of thermoelectric power measurements in the Fe-C multiphase system. Suppositions about the growing and dissolution rate constants reduce the size of the equation system with a gain in computation time.

Luiggi, N.; Betancourt, A. [Univ. de Oriente, Cumana (Venezuela)

1997-02-01T23:59:59.000Z

334

Radiation from Kinetic Poynting Flux Acceleration  

E-Print Network (OSTI)

We derive analytic formulas for the power output and critical frequency of radiation by electrons accelerated by relativistic kinetic Poynting flux, and validate these results with Particle-In-Cell plasma simulations. We find that the in-situ radiation power output and critical frequency are much below those predicted by the classical synchrotron formulae. We discuss potential astrophysical applications of these results.

Edison Liang; Koichi Noguchi

2007-04-13T23:59:59.000Z

335

Reaction kinetics for remodeling oil shale retorting  

DOE Green Energy (OSTI)

Results from recent laboratory kinetic studies at the Lawrence Livermore Laboratory (LLL) on gasification, pyrolysis, and mineral reactions in oil shale are presented. The specific pyrolysis reactions investigated include the decomposition of kerogen, the evolution of oil, hydrogen and C/sub 2/ plus C/sub 3/ hydrocarbons and the formation of a carbonaceous residue. Data describing the evolution of H/sub 2/ and CH/sub 4/ during secondary pyrolysis of the carbonaceous residue are also presented. The mineral reaction kinetics discussed include the decomposition and/or reaction (with silica or silicates) of calcite, dolomite, dawsonite and nahcolite. Rate equations describing the effects of CO/sub 2/ and steam on the reactions of calcite and dolomite are presented. Finally, kinetics describing gasification of the carbonaceous residue by CO/sub 2/ and H/sub 2/O are examined. The above kinetic data are summarized in a set of rate expressions that can be used in numerical modeling of oil shale retorting. The rate equations are general enough for modeling both in-situ and surface retorting processes.

Campbell, J.H.; Burnham, A.K.

1979-01-01T23:59:59.000Z

336

Ocean Circulation Kinetic Energy: Reservoirs, Sources,  

E-Print Network (OSTI)

. The coupling of the generation of different energy forms in the dynamics (in either balanced or wave motions are almost nonexistent in the ocean. www.annualreviews.org · Ocean Circulation Kinetic Energy 255 Annu.Rev.Fluid processes? Are the seemingly different dynamical ranges coupled? 2. THE OCEANIC ENERGY BUDGET We begin

Ferrari, Raffaele

337

Thermodynamics and Kinetics of a Brownian Motor  

E-Print Network (OSTI)

Thermodynamics and Kinetics of a Brownian Motor R. Dean Astumian Nonequilibrium fluctuations particle separation and the design of molecular motors and pumps. A small particle in a liquid is subject in conjunction with an- isotropy to drive a motor in the context of a "ratchet and pawl" device shrunk to micro

Linke, Heiner

338

KINETICS, STABILITY, AND CONTROL. A Selected Bibliography  

SciTech Connect

References to 529 articles on nuclear reactor control, kinetics, and stability published before autumn 1962 are included. Emphasis is on calculations and theory since the references serve as an aid in analyzing the dynamic behavior of SNAP reactor systems. (D.C.W.)

Johnson, R.L.

1963-03-15T23:59:59.000Z

339

Pattern Formation and Growth Kinetics in Eutectic Systems  

Science Conference Proceedings (OSTI)

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 characterize the cell shape and tip undercooling and the experimental results are compared with the predictions of the model. From the investigation of cell/dendrite transition, a model is proposed, from which the condition for the onset of the transition can be obtained.

Jing Teng

2007-12-01T23:59:59.000Z

340

Chemical Kinetic Modeling of Hydrogen Combustion Limits  

Science Conference Proceedings (OSTI)

A detailed chemical kinetic model is used to explore the flammability and detonability of hydrogen mixtures. In the case of flammability, a detailed chemical kinetic mechanism for hydrogen is coupled to the CHEMKIN Premix code to compute premixed, laminar flame speeds. The detailed chemical kinetic model reproduces flame speeds in the literature over a range of equivalence ratios, pressures and reactant temperatures. A series of calculation were performed to assess the key parameters determining the flammability of hydrogen mixtures. Increased reactant temperature was found to greatly increase the flame speed and the flammability of the mixture. The effect of added diluents was assessed. Addition of water and carbon dioxide were found to reduce the flame speed and thus the flammability of a hydrogen mixture approximately equally well and much more than the addition of nitrogen. The detailed chemical kinetic model was used to explore the detonability of hydrogen mixtures. A Zeldovich-von Neumann-Doring (ZND) detonation model coupled with detailed chemical kinetics was used to model the detonation. The effectiveness on different diluents was assessed in reducing the detonability of a hydrogen mixture. Carbon dioxide was found to be most effective in reducing the detonability followed by water and nitrogen. The chemical action of chemical inhibitors on reducing the flammability of hydrogen mixtures is discussed. Bromine and organophosphorus inhibitors act through catalytic cycles that recombine H and OH radicals in the flame. The reduction in H and OH radicals reduces chain branching in the flame through the H + O{sub 2} = OH + O chain branching reaction. The reduction in chain branching and radical production reduces the flame speed and thus the flammability of the hydrogen mixture.

Pitz, W J; Westbrook, C K

2008-04-02T23:59:59.000Z

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


341

Inertial confinement fusion with direct electric generation by magnetic flux comparession  

DOE Green Energy (OSTI)

A high-power-density laser-fusion-reactor concept in investigated in which directed kinetic enery imparted to a large mass of liquid lithium--in which the fusion target is centrally located--is maximized. In turn, this kinetic energy is converted directly to electricity with, potentially, very high efficiency by work done against a pulsed magnetic field applied exterior to the lithium. Because the concept maximizes the blanket thickness per unit volume of lithium, neutron-induced radioactivities in the reaction chamber wall can be many orders of magnitude less than is typical of D-T fusion reactor concepts.

Lasche, G.P.

1983-01-01T23:59:59.000Z

342

Application of fundamental kinetic modeling to industrial chlorination and partial oxidation processes  

E-Print Network (OSTI)

The Fundamental Kinetic Modeling (FKM) method is able to use a growing amount of elementary kinetic rate constant data to simulate industrial reactions and therefore gain insight and predictive capabilities beyond those of traditional empirical kinetic models. Because traditional empirical kinetic models often simplify the underlying kinetics into a single overall reaction, these recently determined values cannot be used directly. In addition to simulating irreducible chemical events as opposed to an overall reaction, the FKM does not make assumptions about microscopic reversibility. To obtain the reverse rate constants, the thermophysical properties for the species are required. Advances in computing technology have made ab initio quantum chemical calculations feasible for oxygenated and chlorinated hydrocarbons. Thermophysical properties for species that cannot be obtained experimentally are now available with greater accuracy than using prior estimating techniques. The FKM method is able to use these values to obtain information about temperature and concentration profiles as well as product distributions and selectivities for a variety of reactor configurations. The application of the FKM method to industrial reactions could be used to optimize existing operating conditions or to predict novel processes. One such chemistry is the oxychlorination of ethane to vinyl chloride. The problem is most easily solved in three steps: the development of a thermal chlorination model, the development of a partial oxidation model, and the combination of the two models with the necessary additional species and reactions. This work focuses on the first two steps. A thermal chlorination model is verified against two sources of experimental data with good quantitative agreement. In addition, differences in product distributions are explained by examining the kinetic pathways. Also, an existing partial oxidation model is combined with newly calculated thermophysical properties. The agreement with two experimental data sources is not as good quantitatively; however, qualitative agreement is observed. Areas for improvement to obtain quantitative agreement are determined.

Han, Joseph Hsiao-Tien

2000-01-01T23:59:59.000Z

343

Evaluating Mesoscale NWP Models Using Kinetic Energy Spectra  

Science Conference Proceedings (OSTI)

Kinetic energy spectra derived from observations in the free atmosphere possess a wavenumber dependence of k?3 for large scales, characteristic of 2D turbulence, and transition to a k?5/3 dependence in the mesoscale. Kinetic energy spectra ...

William C. Skamarock

2004-12-01T23:59:59.000Z

344

Isothermal Ice Crystallization Kinetics in the Gas-Diffusion...  

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

Isothermal Ice Crystallization Kinetics in the Gas-Diffusion Layer of a Proton-Exchange-Membrane Fuel Cell Title Isothermal Ice Crystallization Kinetics in the Gas-Diffusion Layer...

345

Direct conversion technology  

DOE Green Energy (OSTI)

The overall objective of the Direct Conversion Technology task is to develop an experimentally verified technology base for promising direct conversion systems that have potential application for energy conservation in the end-use sectors. This report contains progress of research on the Alkali Metal Thermal-to-Electric Converter (AMTEC) and on the Two-Phase Liquid-Metal MHD Electrical Generator (LMMHD) for the period January 1, 1991 through December 31, 1991. Research on AMTEC and on LMMHD was initiated during October 1987. Reports prepared on previous occasions (Refs. 1--5) contain descriptive and performance discussions of the following direct conversion concepts: thermoelectric, pyroelectric, thermionic, thermophotovoltaic, thermoacoustic, thermomagnetic, thermoelastic (Nitionol heat engine); and also, more complete descriptive discussions of AMTEC and LMMHD systems.

Massier, P.F.; Back, L.H.; Ryan, M.A.; Fabris, G.

1992-01-07T23:59:59.000Z

346

Direct Conversion Technology  

DOE Green Energy (OSTI)

The overall objective of the Direct Conversion Technology task is to develop an experimentally verified technology base for promising direct conversion systems that have potential application for energy conservation in the end-use sectors. Initially, two systems were selected for exploratory research and advanced development. These are Alkali Metal Thermal-to-Electric Converter (AMTEC) and Two-Phase Liquid Metal MD Generator (LMMHD). This report describes progress that has been made during the first six months of 1992 on research activities associated with these two systems. (GHH)

Back, L.H.; Fabris, G.; Ryan, M.A.

1992-07-01T23:59:59.000Z

347

Kinetic Controls on Cu and Pb Sorption by Ferrihydrite  

E-Print Network (OSTI)

nd ed.; Cambridge University Press: New York, 1993. (51) Sparks, D. L. Kinetics of Soil Chemical Processes; Academic Press: New York, 1989. (52) Espenson, J. H. Chemical Kinetics and Reaction Mechanisms, 2Kinetic Controls on Cu and Pb Sorption by Ferrihydrite A N D R E A S C . S C H E I N O

Sparks, Donald L.

348

Kinetic and stationary point-set embeddability for plane graphs  

Science Conference Proceedings (OSTI)

We investigate a kinetic version of point-set embeddability. Given a plane graph G(V,E) where |V|=n, and a set P of n moving points where the trajectory of each point is an algebraic function of constant ... Keywords: kinetic algorithm, kinetic graph drawing, plane graph, point-set embeddability

Zahed Rahmati; Sue H. Whitesides; Valerie King

2012-09-01T23:59:59.000Z

349

Direct Card. SPECIAL SITUATIONS  

E-Print Network (OSTI)

will be deducted. Rental cars Your Direct Card can be used to pay your final balance. Some companies may require cash at ATMs and banks No checks. No lines. No hassles. 24/7 Customer Support Get Account Information number or your date of birth (mm/dd). By activating your card, you accept the Terms and Conditions

Reynolds, Albert C.

350

Direct fired heat exchanger  

DOE Patents (OSTI)

A gas-to-liquid heat exchanger system which transfers heat from a gas, generally the combustion gas of a direct-fired generator of an absorption machine, to a liquid, generally an absorbent solution. The heat exchanger system is in a counterflow fluid arrangement which creates a more efficient heat transfer.

Reimann, Robert C. (Lafayette, NY); Root, Richard A. (Spokane, WA)

1986-01-01T23:59:59.000Z

351

Directional gamma detector  

DOE Patents (OSTI)

An improved directional gamma radiation detector has a collector sandwiched etween two layers of insulation of varying thicknesses. The collector and insulation layers are contained within an evacuated casing, or emitter, which releases electrons upon exposure to gamma radiation. Delayed electrons and electrons entering the collector at oblique angles are attenuated as they pass through the insulation layers on route to the collector.

LeVert, Francis E. (Downers Grove, Knoxville, TN); Cox, Samson A. (Downers Grove, IL)

1981-01-01T23:59:59.000Z

352

The Atmospheric Boundary Layer during Swell: A Field Study and Interpretation of the Turbulent Kinetic Energy Budget for High Wave Ages  

Science Conference Proceedings (OSTI)

Analysis of the turbulent kinetic energy (TKE) budget for five slightly unstable cases with swell has been performed based on measurements of mechanical production, buoyancy production, turbulent transport, and dissipation at five levels over the ...

U. Högström; A. Smedman; E. Sahleé; W. M. Drennan; K. K. Kahma; H. Pettersson; F. Zhang

2009-09-01T23:59:59.000Z

353

ARM - PI Product - Direct Aerosol Forcing Uncertainty  

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

ProductsDirect Aerosol Forcing Uncertainty ProductsDirect Aerosol Forcing Uncertainty Comments? We would love to hear from you! Send us a note below or call us at 1-888-ARM-DATA. Send PI Product : Direct Aerosol Forcing Uncertainty Site(s) NSA SGP TWP General Description Understanding sources of uncertainty in aerosol direct radiative forcing (DRF), the difference in a given radiative flux component with and without aerosol, is essential to quantifying changes in Earth's radiation budget. We examine the uncertainty in DRF due to measurement uncertainty in the quantities on which it depends: aerosol optical depth, single scattering albedo, asymmetry parameter, solar geometry, and surface albedo. Direct radiative forcing at the top of the atmosphere and at the surface as well as sensitivities, the changes in DRF in response to unit changes in

354

Analysis on kinetic chemotaxis models using a functional analytic approach Analysis on kinetic chemotaxis models using a  

E-Print Network (OSTI)

that are applicable at the molecular level. Copyright # 2004 John Wiley & Sons, Ltd. KEYWORDS: kinetic stability of that system are undergoing constant change. This chemical example of replicator kinetic stability is akin in circumstance may dramatically affect the kinetic stability of physical, chemical and biological, systems. So

Hille, Sander

355

React. Kinet.Catal.Lett., Vol.9, No. 4,377-381 (1978) WHAT IS ESSENTIAL TO EXOTIC KINETIC BEHAVIOR?  

E-Print Network (OSTI)

6= 10'. I = 1 I=I 378 #12;TOTH: EXOTIC KINETIC BEHAVIOR? COROLLARIES Immediate application). REFERENCES 1. M. Feinberg: Mathamatical Aspects of Mass Action Kinetics. Chapter 1 of Chemical Reactor Theory-London-New York 1972. 3. J. T6th, P. ~rdi: Models, Problems and Applications of Formal Reaction Kinetics (in

Tóth, János

356

Kinetic and hydrodynamic models of chemotactic aggregation  

E-Print Network (OSTI)

We derive general kinetic and hydrodynamic models of chemotactic aggregation that describe certain features of the morphogenesis of biological colonies (like bacteria, amoebae, endothelial cells or social insects). Starting from a stochastic model defined in terms of N coupled Langevin equations, we derive a nonlinear mean field Fokker-Planck equation governing the evolution of the distribution function of the system in phase space. By taking the successive moments of this kinetic equation and using a local thermodynamic equilibrium condition, we derive a set of hydrodynamic equations involving a damping term. In the limit of small frictions, we obtain a hyperbolic model describing the formation of network patterns (filaments) and in the limit of strong frictions we obtain a parabolic model which is a generalization of the standard Keller-Segel model describing the formation of clusters (clumps). Our approach connects and generalizes several models introduced in the chemotactic literature. We discuss the anal...

Chavanis, Pierre-Henri

2007-01-01T23:59:59.000Z

357

Auxiliary power supply with kinetic energy storage  

SciTech Connect

Alternating current is supplied to an auxiliary load on a from a power supply comprised of a dc-energized inverter and a synchronous machine coupled to the inverter. The inverter supplies the alternating current requirements of the load up to the normal steady state load current magnitude. The synchronous machine stores kinetic energy when the load current load does not exceed its normal steady state magnitude, and converts kinetic energy into electrical energy to supply the load current requirements in excess of its normal steady-state load magnitude and to supply load current whenever the dc source inverter connection is interrupted. Frequency and amplitude of load voltage are regulated by operator commands through control apparatus coupled to the inverter and the synchronous machine.

Plunkett, A.B.; Turnbull, F.G.

1982-03-23T23:59:59.000Z

358

ET Kinetics of Bifunctional Redox Protein Maquettes  

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

Kinetics of Bifunctional Redox Protein Maquettes Kinetics of Bifunctional Redox Protein Maquettes Mitchell W. Mutz, James F. Wishart and George L. McLendon Adv. Chem Ser. 254, Ch. 10, pp. 145-159 Abstract: We prepared three bifunctional redox protein maquettes based on 12-, 16-, and 20-mer three-helix bundles. In each case, the helix was capped with a Co(III) tris-bipyridyl electron acceptor and also functionalized with a C-terminal viologen (1-ethyl-1'-ethyl-4,4'-bipyridinium) donor. Electron transfer (ET) was initiated by pulse radiolysis and flash photolysis and followed spectrometrically to determined average, concentration-independent, first-order rates for the 16-mer and 20-mer maquettes. For the 16-mer bundle, the alpha-helical content was adjusted by the addition of urea or trifluoroethanol to solutions containing the metalloprotein. This

359

Chemical kinetics models for semiconductor processing  

SciTech Connect

Chemical reactions in the gas-phase and on surfaces are important in the deposition and etching of materials for microelectronic applications. A general software framework for describing homogeneous and heterogeneous reaction kinetics utilizing the Chemkin suite of codes is presented. Experimental, theoretical and modeling approaches to developing chemical reaction mechanisms are discussed. A number of TCAD application modules for simulating the chemically reacting flow in deposition and etching reactors have been developed and are also described.

Coltrin, M.E.; Creighton, J.R. [Sandia National Labs., Albuquerque, NM (United States); Meeks, E.; Grcar, J.F.; Houf, W.G. [Sandia National Labs., Livermore, CA (United States); Kee, R.J. [Colorado School of Mines, Golden, CO (United States)

1997-12-31T23:59:59.000Z

360

Inertial range turbulence in kinetic plasmas  

E-Print Network (OSTI)

The transfer of turbulent energy through an inertial range from the driving scale to dissipative scales in a kinetic plasma followed by the conversion of this energy into heat is a fundamental plasma physics process. A theoretical foundation for the study of this process is constructed, but the details of the kinetic cascade are not well understood. Several important properties are identified: (a) the conservation of a generalized energy by the cascade; (b) the need for collisions to increase entropy and realize irreversible plasma heating; and (c) the key role played by the entropy cascade--a dual cascade of energy to small scales in both physical and velocity space--to convert ultimately the turbulent energy into heat. A strategy for nonlinear numerical simulations of kinetic turbulence is outlined. Initial numerical results are consistent with the operation of the entropy cascade. Inertial range turbulence arises in a broad range of space and astrophysical plasmas and may play an important role in the ther...

Howes, G G

2007-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "direct kinetic measurements" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
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361

Inertial range turbulence in kinetic plasmas  

E-Print Network (OSTI)

The transfer of turbulent energy through an inertial range from the driving scale to dissipative scales in a kinetic plasma followed by the conversion of this energy into heat is a fundamental plasma physics process. A theoretical foundation for the study of this process is constructed, but the details of the kinetic cascade are not well understood. Several important properties are identified: (a) the conservation of a generalized energy by the cascade; (b) the need for collisions to increase entropy and realize irreversible plasma heating; and (c) the key role played by the entropy cascade--a dual cascade of energy to small scales in both physical and velocity space--to convert ultimately the turbulent energy into heat. A strategy for nonlinear numerical simulations of kinetic turbulence is outlined. Initial numerical results are consistent with the operation of the entropy cascade. Inertial range turbulence arises in a broad range of space and astrophysical plasmas and may play an important role in the thermalization of fusion energy in burning plasmas.

G. G. Howes

2007-11-27T23:59:59.000Z

362

Direct insolation models  

DOE Green Energy (OSTI)

Several recently published models of the direct component of the broadband insolation are compared for clear sky conditions. The comparison includes seven simple models and one rigorous model that is used as a basis for determining accuracy. Where possible, the comparison is made between the results of each model for each atmospheric constituent (H/sub 2/O, CO/sub 2/, O/sub 3/, O/sub 2/, aerosol and molecular scattering) separately as well as for the combined effect of all of the constituents. Two optimum simple models of varying degrees of complexity are developed as a result of this comparison. The study indicates: aerosols dominate the attenuation of the direct beam for reasonable atmospheric conditions; molecular scattering is next in importance; water vapor is an important absorber; and carbon dioxide and oxygen are relatively unimportant as attenuators of the broadband solar energy.

Bird, R.; Hulstrom, R.L.

1980-01-01T23:59:59.000Z

363

The Autoignition of iso-Cetane: Shock Tube Experiments and Kinetic Modeling  

DOE Green Energy (OSTI)

Iso-cetane (2,2,4,4,6,8,8-heptamethylnonane, C{sub 16}H{sub 34}) is a highly branched alkane reference compound for determining cetane ratings. It is also a candidate branched alkane representative in surrogate mixtures for diesel and jet fuels. Here new experiments and kinetic modeling results are presented for the autoignition of iso-cetane at elevated temperatures and pressures relevant to combustion in internal combustion engines. Ignition delay time measurements were made in reflected shock experiments in a heated shock tube for {Phi} = 0.5 and 1.0 iso-cetane/air mixtures at temperatures ranging from 953 to 1347 K and pressures from 8 to 47 atm. Ignition delay times were measured using electronically excited OH emission, monitored through the shock tube end wall, and piezoelectric pressure transducer measurements, made at side wall locations. A new kinetic mechanism for the description of the oxidation of iso-cetane is presented that is developed based on a previous mechanism for iso-octane. Computed results from the mechanism are found in good agreement with the experimental measurements. To our knowledge, the ignition time measurements and detailed kinetic mechanism for isocetane presented here are the first of their kind.

Oehlschlaeger, M A; Steinberg, J; Westbrook, C K; Pitz, W J

2009-02-25T23:59:59.000Z

364

Propagation of Chaos for a Thermostated Kinetic Model  

E-Print Network (OSTI)

We consider a system of N point particles moving on a d-dimensional torus. Each particle is subject to a uniform field E and random speed conserving collisions. This model is a variant of the Drude-Lorentz model of electrical conduction. In order to avoid heating by the external field, the particles also interact with a Gaussian thermostat which keeps the total kinetic energy of the system constant. The thermostat induces a mean-field type of interaction between the particles. Here we prove that, starting from a product measure, in the large N limit, the one particle velocity distribution satisfies a self consistent Vlasov-Boltzmann equation.. This is a consequence of "propagation of chaos", which we also prove for this model.

F. Bonetto; E. A. Carlen; R. Esposito; J. L. Lebowitz; R. Marra

2013-05-31T23:59:59.000Z

365

Hybrid fluid/kinetic modeling of Pluto's escaping atmosphere  

E-Print Network (OSTI)

Predicting the rate of escape and thermal structure of Pluto's upper atmosphere in preparation for the New Horizons Spacecraft encounter in 2015 is important for planning and interpreting the expected measurements. Having a moderate Jeans parameter Pluto's atmosphere does not fit the classic definition of Jeans escape for light species escaping from the terrestrial planets, nor does it fit the hydrodynamic outflow from comets and certain exoplanets. It has been proposed for some time that Pluto lies in the region of slow-hydrodynamic escape. Using a hybrid fluid/molecular-kinetic model, we previously demonstrated the typical implementation of this model fails to correctly describe the appropriate temperature structure for the upper atmosphere for solar minimum conditions. Here we used a time-dependent solver to allow us to extend those simulations to higher heating rates and we examined fluid models in which Jeans-like escape expressions are used for the upper boundary conditions. We compare these to our hybr...

Erwin, Justin T; Johnson, Robert E

2012-01-01T23:59:59.000Z

366

Letter: Direction and Guidance for Implementing Direct DOE Relationship &  

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

Letter: Direction and Guidance for Implementing Direct DOE Letter: Direction and Guidance for Implementing Direct DOE Relationship & Funding for EMSSABs Letter: Direction and Guidance for Implementing Direct DOE Relationship & Funding for EMSSABs From: Assistant Secretary, Jessie Hill Roberson (EM-11) To: Mr. Monte Wilson, Chair, INEEL Citizens Advisory Board This letter is in response to a November 21, 2003 letter regarding direction and guidance for implementing direct DOE relationship and funding for Environmental Management Site Specific Advisory Boards. Roberson Letter - December 12, 2003 More Documents & Publications Letter: Progress in Implementing a Direct DOE Relationship & Funding for the EMSSABs Letter: Mission, Objectives & Scope of the Site Specific Advisory Board Memorandum: Direction and Guidance for Implementing Direct DOE Relationship

367

Letter: Direction and Guidance for Implementing Direct DOE Relationship &  

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

Letter: Direction and Guidance for Implementing Direct DOE Letter: Direction and Guidance for Implementing Direct DOE Relationship & Funding for EMSSABs Letter: Direction and Guidance for Implementing Direct DOE Relationship & Funding for EMSSABs From: Assistant Secretary, Jessie Hill Roberson (EM-11) To: Mr. Monte Wilson, Chair, INEEL Citizens Advisory Board This letter is in response to a November 21, 2003 letter regarding direction and guidance for implementing direct DOE relationship and funding for Environmental Management Site Specific Advisory Boards. Roberson Letter - December 12, 2003 More Documents & Publications Letter: Progress in Implementing a Direct DOE Relationship & Funding for the EMSSABs Letter: Mission, Objectives & Scope of the Site Specific Advisory Board Memorandum: Direction and Guidance for Implementing Direct DOE Relationship

368

Our purpose and direction Our purpose and direction  

E-Print Network (OSTI)

1 Our purpose and direction #12;Our purpose and direction Contents MINISTERS' FOREWORD 3 organisation 8 Our People 8 Our finances 8 Business sustainability ­ `Greenerways' 9 OUR DIRECTION 10 Our: Financial resources 56 2 #12;Our purpose and direction Ministers' Foreword I am very pleased to be providing

369

Introduction Direct seeding, also known as direct sowing, is  

E-Print Network (OSTI)

Introduction Direct seeding, also known as direct sowing, is an ancient method of woodland that control of competing vegetation is essential for successful tree establishment using direct sowing. Hand, Willoughby (2002) suggests total overall herbicide inputs may be lower in direct seeded woodland due

370

Breakout Session -- TEC Direction  

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

III: TEC III: TEC Direction and Priorities Presented to: Transportation External Coordination Working Group Presented by: Alex Thrower Office of Logistics Management February 7, 2008 San Antonio, Texas 2 Topics of Discussion * Transportation External Coordination Working Group (TEC) charter and membership * Topic group functions * Meeting format 3 TEC Charter and Membership * Mission - TEC was formed in 1992 to improve coordination among the Department of Energy (DOE) and external groups interested in the Department's transportation activities The Office of Civilian Radioactive Waste Management (OCRWM) co-chairs TEC with DOE's Environmental Management Program Provides an opportunity for broad based input and information exchange from varied organizations - Members meet semi-annually to participate in

371

Omni-directional railguns  

DOE Patents (OSTI)

This invention is comprised of a device for electromagetically accelerating projectiles. The invention features two parallel conducting circular plates, a plurality of electrode connections to both upper and lower plates, a support base, and a projectile magazine. A projectile is spring-loaded into a firing position concentrically located between the parallel plates. A voltage source is applied to the plates to cause current to flow in directions defined by selectable, discrete electrode connections on both upper and lower plates. Repulsive Lorentz forces are generated to eject the projectile in a 360 degree range of fire.

Shahinpoor, M.

1994-12-31T23:59:59.000Z

372

Formatting paragraph numbering for directives  

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

MEASUREMENT SENSITIVE DOE G 440.1-8 12-27-06 IMPLEMENTATION GUIDE for use with 10 CFR PART 851 WORKER SAFETY AND HEALTH PROGRAM [This Guide describes suggested nonmandatory approaches for meeting requirements. Guides are not requirements documents and are not construed as requirements in any audit or appraisal for compliance with the parent Policy, Order, Notice, or Manual.] U.S. Department of Energy Washington, D.C. 20585 AVAILABLE ONLINE AT: INITIATED BY: www.directives.doe.gov Office of Health, Safety and Security DOE G 440.1-8 i (and ii) 12-27-06 FOREWORD This Department of Energy (DOE) Guide is available for use by all DOE components and their contractors. Beneficial comments (recommendations, additions, and deletions) and pertinent data that may

373

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

SciTech Connect

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.

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

2012-08-29T23:59:59.000Z

374

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

Science Conference Proceedings (OSTI)

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.

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

2012-08-29T23:59:59.000Z

375

Direct photon-charged hadron azimuthal correlations  

E-Print Network (OSTI)

Azimuthal correlations of direct photons at high transverse energy (8 $<$ E$_T$ $<$ 16 GeV) with away-side hadrons of transverse momentum (3 $<$ p$_T$ $<$ 6 GeV/c) have been measured over a broad range of centrality for $Au+Au$ collisions and $p+p$ collisions at $\\sqrt{s_{NN}}$ = 200 GeV. The presented results are the first measurements at RHIC for $\\gamma$-hadron azimuthal correlations in $Au+Au$ collisions.

Ahmed M. Hamed

2008-06-13T23:59:59.000Z

376

Direct Solar Energy Conversion by the Reduction of CO2  

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

Direct Solar Energy Conversion by the Reduction of CO2 Direct Solar Energy Conversion by the Reduction of CO2 Speaker(s): Reed Jensen Date: August 25, 2005 - 12:00pm Location: Bldg. 90 Reed Jensen has successfully demonstrated the direct solar reduction of CO2 to CO and O2 using a solar concentrator dish and ceramic converter that grew out of his work at Los Alamos National Laboratory. He will discuss the thermochemical, kinetic and spectral properties of the CO2 /CO/ O2 system that enable this process and how the CO is subsequently converted to useful fuels by a range of catalytic processes. He will also discuss the technical difficulties associated with the design, construction and operation of a multi-component optical system that must operate at high temperatures. Results from a prototype system will be discussed defining the efficiencies

377

Kinetics of Anionic Surfactant Anoxic Degradation  

E-Print Network (OSTI)

The biodegradation kinetics of Geropon TC-42 (trademark) by an acclimated culture was investigated in anoxic batch reactors to determine biokinetic coefficients to be implemented in two biofilm mathematical models. Geropon TC-42 (trademark) is the surfactant commonly used in space habitation. The two biofilm models differ in that one assumes a constant biofilm density and the other allows biofilm density changes based on space occupancy theory. Extant kinetic analysis of a mixed microbial culture using Geropon TC-42 (trademark) as sole carbon source was used to determine cell yield, specific growth rate, and the half-saturation constant for S0/X0 ratios of 4, 12.5, and 34.5. To estimate cell yield, linear regression analysis was performed on data obtained from three sets of simultaneous batch experiments for three S0/X0 ratios. The regressions showed non-zero intercepts, suggesting that cell multiplication is not possible at low substrate concentrations. Non-linear least-squares analysis of the integrated equation was used to estimate the specific growth rate and the half-saturation constant. Net specific growth rate dependence on substrate concentration indicates a self-inhibitory effect of Geropon TC-42 (trademark). The flow rate and the ratio of the concentrations of surfactant to nitrate were the factors that most affected the simulations. Higher flow rates resulted in a shorter hydraulic retention time, shorter startup periods, and faster approach to a steady-state biofilm. At steady-state, higher flow resulted in lower surfactant removal. Higher influent surfactant/nitrate concentration ratios caused a longer startup period, supported more surfactant utilization, and biofilm growth. Both models correlate to the empirical data. A model assuming constant biofilm density is computationally simpler and easier to implement. Therefore, a suitable anoxic packed bed reactor for the removal of the surfactant Geropon TC-42 (trademark) can be designed by using the estimated kinetic values and a model assuming constant biofilm density.

Camacho, Julianna G.

2010-05-01T23:59:59.000Z

378

Inflation by purely kinetic coupled gravity  

E-Print Network (OSTI)

We study a purely kinetic coupled scalar-tensor gravity. We use FRW metric and obtain the modified Friedmann equations subject to an effective perfect fluid including energy density $\\rho_{\\phi}=\\rho_{g}+\\rho_{_G}$ and pressure $p_{\\phi}=p_{g}+p_{_G}$, where $(\\rho_{g}, p_{g})$ and $(\\rho_{_G}, p_{_G})$ define the perfect fluids corresponding to the coupling of scalar field dynamics with metric and Einstein tensors, respectively. We find that the inflation can occur in this model provided that $p_{_G}=-\\rho_{_G}$. We define Hubble slow-role parameters and find that the Hubble slow-role regime means $\\rho_{_{g}}\\ll\\rho_{_{G}}$. It turns out that the energy is not conserved for the scalar field and its kinetic energy is growing exponentially during inflation. It is proposed that this energy may be supplied by the quantum fluctuations of vacuum. This rapid transfer of energy density from vacuum to the scalar field may solve the cosmological constant problem. When $\\rho_{_{g}}$ becomes sufficiently large, the Hubble parameter starts decreasing and $\\rho_{_{g}}$ becomes comparable with $\\rho_{_{G}}$, hence the slow-role approximation is violated, and the inflation is ended. The large energy density of the scalar field may be transformed, partly into the matter, and partly into the radiation, and the universe experiences a reheating phase. At late times, the kinetic energy of the scalar field decreases as $a^{-6}$ and the remnant energy density of the scalar field may become a source of dark matter. Also, we study the cosmological perturbations during the inflation and obtain the behaviors of perturbations inside and outside the horizon. These results are in agreement with those obtained in common inflationary scenarios.

F. Darabi; A. Parsiya

2013-12-04T23:59:59.000Z

379

Direct photon interferometry  

E-Print Network (OSTI)

Abstract. We consider recent developments in the theory of the two-photon interferometry in ultrarelativistic heavy ion collisions with emphasis on the difference between photon and hadron interferometry. We review the available experimental results and discuss possibilities of measurement of the photon Bose-Einstein correlations in ongoing and future experiments.

D. Peressounko

2005-01-01T23:59:59.000Z

380

Direct photon interferometry  

E-Print Network (OSTI)

We consider recent developments in the theory of the two-photon interferometry in ultrarelativistic heavy ion collisions with emphasis on the difference between photon and hadron interferometry. We review the available experimental results and discuss possibilities of measurement of the photon Bose-Einstein correlations in ongoing and future experiments.

D. Peressounko

2005-12-08T23:59:59.000Z

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


381

The Hydriding Kinetics of Organic Hydrogen Getters  

DOE Green Energy (OSTI)

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 0.76. Silicone rubber based DEB getters hydride at a much lower rate, have little dependence on reaction extent, have a higher kinetic order in pressure (0.87), and have a lower activation energy. The kinetics of the reaction as a function of hydrogen pressure, stoichiometry, and temperature for hydrogen and deuterium near ambient temperature (0 to 75 C) for pressures near or below 100 Pa over a wide range (in some cases, the complete) hydrogenation range are presented along with multi-dimensional rate models.

Powell, G. L.

2002-02-11T23:59:59.000Z

382

SPECTRUM OF KINETIC-ALFVEN TURBULENCE  

Science Conference Proceedings (OSTI)

A numerical study of strong kinetic-Alfven turbulence at scales smaller than the ion gyroscale is presented, and a phenomenological model is proposed that argues that magnetic and density fluctuations are concentrated mostly in two-dimensional structures, which leads to their Fourier energy spectra E(k ){proportional_to}k {sup -8/3} , where k is the wavevector component normal to the strong background magnetic field. The results may provide an explanation for recent observations of magnetic and density fluctuations in the solar wind at sub-proton scales.

Boldyrev, Stanislav; Perez, Jean Carlos [Department of Physics, University of Wisconsin, Madison, WI 53706 (United States)

2012-10-20T23:59:59.000Z

383

GEOMETRY, HEAT REMOVAL AND KINETICS SCOPING MODELS FOR HYDROGEN STORAGE SYSTEMS  

DOE Green Energy (OSTI)

It is recognized that detailed models of proposed hydrogen storage systems are essential to gain insight into the complex processes occurring during the charging and discharging processes. Such insight is an invaluable asset for both assessing the viability of a particular system and/or for improving its design. The detailed models, however, require time to develop and run. Clearly, it is much more efficient to begin a modeling effort with a good system design and to progress from that point. To facilitate this approach, it is useful to have simplified models that can quickly estimate optimal loading and discharge kinetics, effective hydrogen capacities, system dimensions and heat removal requirements. Parameters obtained from these models can then be input to the detailed models to obtain an accurate assessment of system performance that includes more complete integration of the physical processes. This report describes three scoping models that assess preliminary system design prior to invoking a more detailed finite element analysis. The three models address the kinetics, the scaling and heat removal parameters of the system, respectively. The kinetics model is used to evaluate the effect of temperature and hydrogen pressure on the loading and discharge kinetics. As part of the kinetics calculations, the model also determines the mass of stored hydrogen per mass of hydride (in a particular reference form). As such, the model can determine the optimal loading and discharge rates for a particular hydride and the maximum achievable loading (over an infinite period of time). The kinetics model developed with the Mathcad{reg_sign} solver, runs in a mater of seconds and can quickly be used to identify the optimal temperature and pressure for either the loading or discharge processes. The geometry scoping model is used to calculate the size of the system, the optimal placement of heat transfer elements, and the gravimetric and volumetric capacities for a particular geometric configuration and hydride. This scoping model is developed in Microsoft Excel{reg_sign} and inputs the mass of hydrogen to be stored, mass of stored hydrogen to mass of hydride (from the kinetics model), component densities, etc. The heat removal scoping model is used to calculate coolant flowrates, pressure drops and temperature increases over the length of the cooling channels. The model also calculates the convection heat transfer coefficient required to remove the heat of reaction associated with hydrogen uptake. The heat removal model inputs dimensions and the mass of hydrogen to be stored directly from the geometry scoping model. Additionally, the model inputs the heats of reaction, the thermal properties of the coolant and the time required to charge the bed.

Hardy, B

2007-11-16T23:59:59.000Z

384

Home: Directives, Delegations, and Requirements  

NLE Websites -- All DOE Office Websites

content. | Skip to navigation content. | Skip to navigation Site Map Contact Us Current Documents Archived Documents Entire Site only in current section Advanced Search... U.S. Department of Energy Office of Management Directives, Delegations, and Requirements Sections Home Directives Current Directives Draft Directives Archives Delegations Current Delegations Current Designations Rescinded Organizations' Assignment of Responsibility Development & Review RevCom Writers' Tools DPC Corner References News and Updates Help Personal tools You are here: Office of Management » Directives, Delegations, and Requirements Info Home Directives are the Department of Energy's primary means of establishing policies, requirements, responsibilities, and procedures for Departmental elements and contractors. Directive

385

SRNL - Directions and Maps  

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

Map of SRS, with Georgia and South Carolina Map of SRS, with Georgia and South Carolina Directions and Maps The Savannah River National Laboratory is located at the Savannah River Site , a 310 square mile site located in the southeastern coastal area of the United States in the state of South Carolina. It is bordered to the west by the Savannah River and Georgia, and is close to several major cities, including Augusta and Savannah (Ga.), Columbia, Greenville, and Charleston (S.C.). It is in an area residents refer to as the Central Savannah River Area, or CSRA. The Aiken County Technology Laboratory (which houses SRNL's biotechnology laboratories and certain waste treatment technology laboratories) and the Center for Hydrogen Research are located at Aiken County's Savannah River Research Campus, located adjacent to SRS.

386

Conclusions and Policy Directions,  

SciTech Connect

This chapter briefly revisits the constraints and opportunities of mitigation and adaptation, and highlights and the multiple linkages, synergies and trade-offs between mitigation, adaptation and urban development. The chapter then presents future policy directions, focusing on local, national and international principles and policies for supporting and enhancing urban responses to climate change. In summary, policy directions for linking climate change responses with urban development offer abundant opportunities; but they call for new philosophies about how to think about the future and how to connect different roles of different levels of government and different parts of the urban community. In many cases, this implies changes in how urban areas operate - fostering closer coordination between local governments and local economic institutions, and building new connections between central power structures and parts of the population who have often been kept outside of the circle of consultation and discourse. The difficulties involved in changing deeply set patterns of interaction and decision-making in urban areas should not be underestimated. Because it is so difficult, successful experiences need to be identified, described and widely publicized as models for others. However, where this challenge is met, it is likely not only to increase opportunities and reduce threats to urban development in profoundly important ways, but to make the urban area a more effective socio-political entity, in general - a better city in how it works day to day and how it solves a myriad of problems as they emerge - far beyond climate change connections alone. It is in this sense that climate change responses can be catalysts for socially inclusive, economically productive and environmentally friendly urban development, helping to pioneer new patterns of stakeholder communication and participation.

Wilbanks, Thomas J [ORNL; Romero-Lankao, Paty [National Center for Atmospheric Research (NCAR); Gnatz, P [National Center for Atmospheric Research (NCAR)

2011-01-01T23:59:59.000Z

387

Fluidized-bed pyrolysis of oil shale: oil yield, composition, and kinetics  

SciTech Connect

A quartz isothermal fluidized-bed reactor has been used to measure kinetics and oil properties relevant to surface processing of oil shale. The rate of oil formation has been described with two sequential first-order rate equations characterized by two rate constants, k/sub 1/ = 2.18 x 10/sup 10/ exp(-41.6 kcal/RT) s/sup -1/ and k/sub 2/ = 4.4 x 10/sup 6/ exp(-29.7 kcal/RT) s/sup -1/. These rate constants together with an expression for the appropriate weighting coefficients describe approximately 97/sup +/% of the total oil produced. A description is given of the results of different attempts to mathematically describe the data in a manner suitable for modeling applications. Preliminary results are also presented for species-selective kinetics of methane, ethene, ethane and hydrogen, where the latter is clearly distinguished as the product of a distinct intermediate. Oil yields from Western oil shale are approximately 100% Fischer assay. Oil composition is as expected based on previous work and the higher heating rates (temperatures) inherent in fluidized-bed pyrolysis. Neither the oil yield, composition nor the kinetics varied with particle size between 0.2 and 2.0 mm within experimental error. The qualitatively expected change in oil composition due to cracking was observed over the temperature range studied (460 to 540/sup 0/C). Eastern shale exhibited significantly faster kinetics and higher oil yields than did Western shale.

Richardson, J H; Huss, E B; Ott, L L; Clarkson, J E; Bishop, M O; Taylor, J R; Gregory, L J; Morris, C J

1982-09-01T23:59:59.000Z

388

Data quality objectives for the reaction kinetics studies of K West fuel samples  

DOE Green Energy (OSTI)

The Data Quality Objectives (DQOs) were established for the reaction kinetics studies of the first group of fuel samples shipped from the K West Basin to the Hanford 327 Building hot cells for examinations. A Thermo-Gravimetric Analysis (TGA) system was selected for these measurements and associated hydrogen release and ignition temperature testing. These examinations are an extension of the conditioning testing of sibling samples described in WHC-SD-SNF-DQO-004, Data Quality Objectives for the Initial Fuel Conditioning Examinations.

Lawrence, L.A. [Westinghouse Hanford Co., Richland, WA (United States); Abrefah, J. [Pacific Northwest National Lab., Richland, WA (United States)

1995-12-01T23:59:59.000Z

389

Chemical Kinetic Reaction Mechanisms for Combustion of Hydrocarbon and Other Types of Chemical Fuels  

DOE Data Explorer (OSTI)

Reaction mechanisms have been tested and validated extensively through comparisons between computed results and measured data from laboratory experiments (e.g., shock tubes, laminar flames, rapid compression machines, flow reactors, stirred reactors) and from practical systems (e.g., diesel engines, spark-ignition engines, homogeneous charge, compression ignition (HCCI) engines). These kinetic models are used to examine a wide range of combustion systems.[Taken from https://www-pls.llnl.gov/?url=science_and_technology-chemistry-combustion

390

Spatial redistribution of turbulent and mean kinetic energy  

Science Conference Proceedings (OSTI)

The turbulent spatial redistribution of turbulent and mean kinetic energy and its exchange is investigated in the framework of an K-{epsilon} model in a magnetized plasma column. The kinetic energy is transferred from the turbulence into the zonal flow around the shear layer. The Reynolds stress profile adjusts to the shear layer, which results in a transport of mean kinetic energy from the region around the shear layer into the shear layer.

Manz, P.; Xu, M.; Fedorczak, N.; Thakur, S. C.; Tynan, G. R. [Center for Momentum Transport and Flow Organization,University of California at San Diego, San Diego, California 92093 (United States); Center for Energy Research, University of California at San Diego, San Diego, California 92093 (United States)

2012-01-15T23:59:59.000Z

391

Thermo -Dynamic & -Kinetic Modeling to Quantify the Evolution of ...  

Science Conference Proceedings (OSTI)

The thermo-kinetic model is applied on various chemical compositions of type ... Application of the Phase-Field Model to Four-Phase Reactions in Ternary Alloys.

392

Kinetic Simulations of Fusion Energy Dynamics at the Extreme...  

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

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...

393

An Integrated CALPHAD Tool for Modeling Precipitation Kinetics ...  

Science Conference Proceedings (OSTI)

Presentation Title, An Integrated CALPHAD Tool for Modeling Precipitation Kinetics and Accelerating Materials Design. Author(s), Qing Chen, Herng-Jeng Jou, ...

394

Dissolution Kinetics of Steelmaking Slag and Its Promotion for the ...  

Science Conference Proceedings (OSTI)

Presentation Title, Dissolution Kinetics of Steelmaking Slag and Its Promotion for the Growth of Algae. Author(s), Chunfang Zi, Kai Huang, Lianyun Liu, Xiaohui ...

395

Kinetics of Supercritical Water Reformation of Ethanol to H  

Science Conference Proceedings (OSTI)

Sep 16, 2007 ... Description Kinetics of the supercritical water reformation of ethanol was experimentally studied in a tubular reactor made of Inconel 625 alloy.

396

Kinetic characterization of enhanced lipase activity on oil bodies  

Science Conference Proceedings (OSTI)

reaction kinetics of oil bodies versus oil emulsions as sub- strates for lipolytic ... of hydrolysis for the oil body system was comparatively very low due to a brief ...

397

Defect Chemistry and Kinetics of Electrons in Ion Conducting Materials  

Science Conference Proceedings (OSTI)

Presentation Title, Defect Chemistry and Kinetics of Electrons in Ion Conducting Materials – Recent Results and Applications. Author(s), Hans D. Wiemhöfer.

398

Particle Size Distribution Model for Leaching Kinetics of Alumina  

Science Conference Proceedings (OSTI)

Presentation Title, Particle Size Distribution Model for Leaching Kinetics of Alumina. Author(s), Li Bao, Ting-an Zhang, Weimin Long, Anh V Nguyen, Guozhi Lv, ...

399

A Kinetic Monte Carlo Model for Material Aging: Simulations of ...  

Science Conference Proceedings (OSTI)

In this paper, we develop a kinetic Monte Carlo framework aiming at ... A Controlled Stress Energy Minimization Method for Coarse-grained Atomistic Simulation.

400

Thermal Stabilization of Nanocrystalline Grain Size by Kinetic and ...  

Science Conference Proceedings (OSTI)

This talk will review both kinetic and thermodynamic mechanisms and ... Basic Criteria for Formation of Growth Twins in High Stacking Fault Energy Metals.

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


401

Oxygen Exchange Kinetics on SOFC Cathode Materials: Importance ...  

Science Conference Proceedings (OSTI)

Presentation Title, Oxygen Exchange Kinetics on SOFC Cathode Materials: Importance of Ionic and Electronic Carriers. Author(s), Rotraut Merkle, Lei Wang,

402

Kinetic Modeling of Esterification of Ethylene Glycol with Acetic Acid  

SciTech Connect

The reaction kinetics of the esterification of ethylene glycol with acetic acid in the presence of cation exchange resin has been studied and kinetic models based on empirical and Langmuir approach has been developed. The Langmuir based model involving eight kinetic parameters fits experimental data much better compared to empirical model involving four kinetic parameters. The effect of temperature and catalyst loading on the reaction system has been analyzed. Further, the activation energy and frequency factor of the rate constants for Langmuir based model has been estimated.

Yadav, Vishnu P.; Maity, Sunil K. [Department of Chemical Engineering, Indian Institute of Technology, Hyderabad, Ordnance Factory Estate, Yeddumailiram-502205, Andhra Pradesh (India); Mukherjee, Rudra Palash [Department of Chemical Engineering, National Institute of Technology, Durgapur, Mahatma Gandhi Avenue, Durgapur-713209, West Bengal (India); Bantraj, Kandi [Department of Chemical Engineering, National Institute of Technology, Rourkela-769008, Orissa (India)

2010-10-26T23:59:59.000Z

403

3.205 Thermodynamics and Kinetics of Materials, Fall 2003  

E-Print Network (OSTI)

Laws of thermodynamics applied to materials and materials processes. Solution theory. Equilibrium diagrams. Overview of fluid transport processes. Kinetics of processes that occur in materials, including diffusion, phase ...

Allen, Samuel M.

404

Kinetics, Transport, and Structure in Hard and Soft Materials - TMS  

Science Conference Proceedings (OSTI)

Jul 25, 2007 ... REVIEWED BY: Stephen Rankin, associate professor, University of Kentucky. In his book Kinetics, Transport, and Structure in Hard and Soft ...

405

Direct measurements improve estimates of dairy greenhouse-gas emissions  

E-Print Network (OSTI)

VOLUME 63 , NUMBER 2 Anaerobic digestion systems could berates (USDA 2004). Anaerobic digestion systems (cov- eredtreatment stand- point, anaerobic digestion systems could be

Mitloehner, Frank M; Sun, Huawei; Karlik, John F

2009-01-01T23:59:59.000Z

406

Direct Aerosol Forcing: Sensitivity to Uncertainty in Measurements...  

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

i.e., single scattering albedo and asymmetry parameter, and situational variables, i.e., solar geometry and surface albedo, and the wavelength dependencies of these quantities....

407

Direct measurement of thin-film thermoelectric figure of merit  

E-Print Network (OSTI)

area. The parasitic heat conduction from the device mesaconsider parasitic heat conduction via the metallead as well as heat conduction in the ?lm and Si 3 N 4

2009-01-01T23:59:59.000Z

408

Direct Measurement of Recirculation In the Alaskan Stream  

Science Conference Proceedings (OSTI)

Three drifting buoys were deployed off Kodiak Island and tracked by satellite in summer 1978; all three veered out of the southwestward flowing Alaskan Stream and moved to the cut and northeast around the Gulf of Alaska gyre. This is the first ...

R. K. Reed

1980-06-01T23:59:59.000Z

409

NCNR Direct Measurement of Reaction Front in Photoresists  

Science Conference Proceedings (OSTI)

... The semiconductor industry is rapidly approaching the need to fabricate sub-100 nano meter structures to continue performance increases in ...

410

Foreign Direct Investment in U  

Gasoline and Diesel Fuel Update (EIA)

Foreign Direct Investment in U.S. Energy in 1998 Foreign Direct Investment in U.S. Energy in 1998 Foreign Direct Investment Foreign Direct Investment Foreign Direct Investment Foreign Direct Investment in U.S. Energy in U.S. Energy in U.S. Energy in U.S. Energy in 1998 in 1998 in 1998 in 1998 November 2000 Energy Information Administration/Foreign Direct Investment in U.S. Energy in 1998 Contacts This report was prepared in the Office of Energy Markets and End Use of the Energy Information Administration, U.S. Department of Energy, under the general direction of W. Calvin Kilgore. The project was directed by Mark E. Rodekohr, Director of the Energy Markets and Contingency Information Division (202) 586-1441, and Mary E. Northup, the Team Leader for Financial Analysis (202) 586-1383. Specific technical information concerning this

411

Memorandum: Direction and Guidance for Implementing Direct DOE Relationship  

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

Direction and Guidance for Implementing Direct DOE Direction and Guidance for Implementing Direct DOE Relationship & Funding for the EMSSAB Memorandum: Direction and Guidance for Implementing Direct DOE Relationship & Funding for the EMSSAB From: Designated Federal Officer, Sandra L. Waisley (EM-11) To: SSAB Members (G. Stegner, J. Reising, G. Bowman, T. Taylor, C. Gertz, B. Murphie, S. McCracken, M. Marvin, J. Rampe, A. Doswell, C. Anderson, B. Wethington, S. Brennan, K. Kozeliski, D. Dollins, P. Halsey, Y. Sherman, L. Bratcher, R. Warther, K. Klein, R. Schepens, F. Lockhart, J. Allison, R. Erickson, E. Sellers, K. Carlson, G. Boyd, R. Butler) The memorandum informs of Assistant Secrectary Roberson's direction and guidance for implementing a DOE direct relationship and funding approach for EM's Site-Specific Advisory Board (EMSSAB).

412

Direct measurements of two-dimensional velocity profiles in direct current glow discharge dusty plasmas  

E-Print Network (OSTI)

´nyi, and E. Gru¨n, Science 280, 88 1998 . 3 D. A. Mendis, Astrophys. Space Sci. 176, 163 1991 . 4 G. S. A. Mendis, Geophys. Res. Lett. 22, 2069 1995 . 11 A. Barkan, R. L. Merlino, and N. D'Angelo, Phys

Thomas Jr., Edward

413

The Response of Wave Directions to Changing Wind Directions  

Science Conference Proceedings (OSTI)

From the premise that the net growth of wave energy induced by wind is centered around the wind direction, a relaxation model for the response of the main wave direction to changes in the wind direction for young sea states is derived. The time ...

L. H. Holthuijsen; A. J. Kuik; E. Mosselman

1987-07-01T23:59:59.000Z

414

Quantitative Measurements of CME-driven Shocks from LASCO Observations  

E-Print Network (OSTI)

In this paper, we demonstrate that CME-driven shocks can be detected in white light coronagraph images and in which properties such as the density compression ratio and shock direction can be measured. Also, their propagation direction can be deduced via simple modeling. We focused on CMEs during the ascending phase of solar cycle 23 when the large-scale morphology of the corona was simple. We selected events which were good candidates to drive a shock due to their high speeds (V>1500 km/s). The final list includes 15 CMEs. For each event, we calibrated the LASCO data, constructed excess mass images and searched for indications of faint and relatively sharp fronts ahead of the bright CME front. We found such signatures in 86% (13/15) of the events and measured the upstream/downstream densities to estimate the shock strength. Our values are in agreement with theoretical expectations and show good correlations with the CME kinetic energy and momentum. Finally, we used a simple forward modeling technique to estimate the 3D shape and orientation of the white light shock features. We found excellent agreement with the observed density profiles and the locations of the CME source regions. Our results strongly suggest that the observed brightness enhancements result from density enhancements due to a bow-shock structure driven by the CME.

Veronica Ontiveros; Angelos Vourlidas

2008-11-24T23:59:59.000Z

415

An experimental and kinetic study of syngas/air combustion at elevated temperatures and the effect of water addition  

E-Print Network (OSTI)

An experimental and kinetic study of syngas/air combustion at elevated temperatures and the effect 20 December 2011 Keywords: Syngas combustion Elevated temperatures Water addition Laminar flame speed a b s t r a c t Laminar flame speeds of premixed syngas/air mixtures were measured at various fuel

Qiao, Li

416

Direct Photons in Heavy-Ion Collisions  

E-Print Network (OSTI)

A brief overview of direct-photon measurements in ultra-relativistic nucleus-nucleus collisions is given. The results for Pb+Pb collisions at sqrt{s_NN} = 17.3 GeV and for Au+Au collisions at sqrt{s_NN} = 200 GeV are compared to estimates of the direct-photon yield from hard scattering. Both results leave room for a significant thermal photon component. A description purely based on hard scattering processes, however, is not ruled out so far.

Klaus Reygers

2006-11-06T23:59:59.000Z

417

Geothermal Technologies Program: Direct Use  

DOE Green Energy (OSTI)

This general publication describes geothermal direct use systems, and how they have been effectively used throughout the country. It also describes the DOE program R&D efforts in this area, and summarizes several projects using direct use technology.

Not Available

2004-08-01T23:59:59.000Z

418

Laser or charged-particle-beam fusion reactor with direct electric generation by magnetic flux compression  

DOE Patents (OSTI)

A high-power-density-laser or charged-particle-beam fusion reactor system maximizes the directed kinetic energy imparted to a large mass of liquid lithium by a centrally located fusion target. A fusion target is embedded in a large mass of lithium, of sufficient radius to act as a tritium breeding blanket, and provided with ports for the access of beam energy to implode the target. The directed kinetic energy is converted directly to electricity with high efficiency by work done against a pulsed magnetic field applied exterior to the lithium. Because the system maximizes the blanket thickness per unit volume of lithium, neutron-induced radioactivities in the reaction chamber wall are several orders of magnitude less than is typical of other fusion reactor systems. 25 figs.

Lasche, G.P.

1987-02-20T23:59:59.000Z

419

Laser or charged-particle-beam fusion reactor with direct electric generation by magnetic flux compression  

SciTech Connect

A high-power-density laser or charged-particle-beam fusion reactor system maximizes the directed kinetic energy imparted to a large mass of liquid lithium by a centrally located fusion target. A fusion target is embedded in a large mass of lithium, of sufficient radius to act as a tritium breeding blanket, and provided with ports for the access of beam energy to implode the target. The directed kinetic energy is converted directly to electricity with high efficiency by work done against a pulsed magnetic field applied exterior to the lithium. Because the system maximizes the blanket thickness per unit volume of lithium, neutron-induced radioactivities in the reaction chamber wall are several orders of magnitude less than is typical of other fusion reactor systems.

Lasche, George P. (Arlington, VA)

1988-01-01T23:59:59.000Z

420

ON THE EMERGENCE OF BIOLOGICAL COMPLEXITY: LIFE AS A KINETIC STATE OF MATTER  

E-Print Network (OSTI)

, whereas for replicating chemical systems selection is effectively kinetic. Building on an extension. Keywords: biological complexification, chemical evolution, kinetic stability, kinetic state of matter that are kinetically more stable. So though all chemical reactions are governed by a combination of kinetic

Pross, Addy

Note: This page contains sample records for the topic "direct kinetic measurements" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
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to obtain the most current and comprehensive results.


421

Kinetic Energy Systems | Open Energy Information  

Open Energy Info (EERE)

Systems Systems Jump to: navigation, search Name Kinetic Energy Systems Place Ocala, Florida Zip 34476 Sector Hydro Product Designs and develops tidal generators. Has notably patented the KESC Tidal Generator which is based on free flow hydrodynamics. Coordinates 29.187525°, -82.140394° Loading map... {"minzoom":false,"mappingservice":"googlemaps3","type":"ROADMAP","zoom":14,"types":["ROADMAP","SATELLITE","HYBRID","TERRAIN"],"geoservice":"google","maxzoom":false,"width":"600px","height":"350px","centre":false,"title":"","label":"","icon":"","visitedicon":"","lines":[],"polygons":[],"circles":[],"rectangles":[],"copycoords":false,"static":false,"wmsoverlay":"","layers":[],"controls":["pan","zoom","type","scale","streetview"],"zoomstyle":"DEFAULT","typestyle":"DEFAULT","autoinfowindows":false,"kml":[],"gkml":[],"fusiontables":[],"resizable":false,"tilt":0,"kmlrezoom":false,"poi":true,"imageoverlays":[],"markercluster":false,"searchmarkers":"","locations":[{"text":"","title":"","link":null,"lat":29.187525,"lon":-82.140394,"alt":0,"address":"","icon":"","group":"","inlineLabel":"","visitedicon":""}]}

422

Detailed Kinetic Modeling of Gasoline Surrogate Mixtures  

DOE Green Energy (OSTI)

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.

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

2009-03-09T23:59:59.000Z

423

Metal Oxidation Kinetics and the Transition from Thin to Thick Films  

SciTech Connect

We report an investigation of growth kinetics and transition from thin to thick films during metal oxidation. In the thin film limit (< 20 nm), Cabrera and Mott’s theory is usually adopted by explicitly considering ionic drift through the oxide in response to electric fields, where the growth kinetics follow an inverse logarithmic law . It is generally accepted that Wagner’s theory, involving self-diffusion, is valid only in the limit of thick film regime (>1?m) and leads to parabolic growth kinetics , where l is the oxide film thickness. Theory presented here unifies the two models and provides a complete description of oxidation including the transition from thin to thick film. The range of validity of Cabrera and Mott’s theory and Wagner’s theory can be well defined in terms of the Debye-Hückel screening length. The transition from drift-dominated ionic transport for thin film to diffusion-dominated transport for thick film is found to strictly follow the direct logarithmic law that is frequently observed in many experiments.

Xu, Zhijie; Rosso, Kevin M.; Bruemmer, Stephen M.

2012-09-01T23:59:59.000Z

424

Thermally driven escape from Pluto's atmosphere: A combined fluid/kinetic model  

E-Print Network (OSTI)

A combined fluid/kinetic model is developed to calculate thermally driven escape of N2 from Pluto's atmosphere for two solar heating conditions: no heating above 1450 km and solar minimum heating conditions. In the combined model, one-dimensional fluid equations are applied for the dense part of the atmosphere, while the exobase region is described by a kinetic model and calculated by the direct simulation Monte Carlo method. Fluid and kinetic parts of the model are iteratively solved in order to maintain constant total mass and energy fluxes through the simulation region. Although the atmosphere was found to be highly extended, with an exobase altitude at ~6000 km at solar minimum, the outflow remained subsonic and the escape rate was within a factor of two of the Jeans rate for the exobase temperatures determined. This picture is drastically different from recent predictions obtained solely using a fluid model which, in itself, requires assumptions about atmospheric density, flow velocity and energy flux ca...

Tucker, O J; Deighan, J I; Volkov, A N; Johnson, R E

2011-01-01T23:59:59.000Z

425

Extracting biochemical reaction kinetics from time series data  

E-Print Network (OSTI)

Abstract. We consider the problem of inferring kinetic mechanisms for biochemical reactions from time series data. Using a priori knowledge about the structure of chemical reaction kinetics we develop global nonlinear models which use elementary reactions as a basis set, and discuss model construction using top-down and bottom-up approaches. 1

Edmund J. Crampin; Patrick E. Mcsharry; Santiago Schnell

2004-01-01T23:59:59.000Z

426

Computing realizations of reaction kinetic networks with given properties  

E-Print Network (OSTI)

engineering­chemical kinetics, chemical thermodynamics, and fluid mechanics­are developed in the second CHEME 3900 Chemical Kinetics and Reactor Design CHEME 4320 Chemical Engineering Laboratory CHEME 4620UndergradUate degree Program as a chemical engineer you'll work with chemical change and chemical

Gorban, Alexander N.

427

Nonlinear adaptive control for bioreactors with unknown kinetics  

Science Conference Proceedings (OSTI)

We consider a control problem for a single bioreaction occurring in a continuous and well-mixed bioreactor, assuming that the bioreaction's kinetics is not represented by a validated model. We develop a nonlinear controller and prove the global asymptotic ... Keywords: Continuous bioprocesses, Nonlinear adaptive control, Unknown kinetics, Wastewater treatment

Ludovic Mailleret; Olivier Bernard; Jean-Philippe Steyer

2004-08-01T23:59:59.000Z

428

Towards cleaner combustion engines through groundbreaking detailed chemical kinetic models  

E-Print Network (OSTI)

Towards cleaner combustion engines through groundbreaking detailed chemical kinetic models of more predictive and more accurate detailed chemical kinetic models for the combustion of fuels that the combustion of liquid fuels will remain the main source of energy for transportation for the next 50 years.1

429

Kinetics of Diuron Adsorption onto Activated Carbon Fiber  

Science Conference Proceedings (OSTI)

A study was conducted on the adsorption kinetics of diuron from aqueous solutions onto activated carbon fiber. The results showed that the formation of hydrogen bonds between diuron and water, and temperature variations may possibly affect the adsorption ... Keywords: activated carbon fiber, diuron adsorption, kinetic models, hydrogen bonds

Jianhua Xu; Yabing Sun; Zhenyu Li; Jingwei Feng

2011-03-01T23:59:59.000Z

430

Pyrolysis kinetics for western and eastern oil shale  

DOE Green Energy (OSTI)

Oil yield and kinetic results are reviewed for Western (Colorado Mahogany zone) and Eastern (Sunbury and Ohio (Cleveland member)) oil shales for conditions ranging from those encountered in in-situ processing to those in fluidized-bed retorting. The authors briefly summarize kinetic models for the pyrolysis reactions. Oil yields from Eastern shale are much more sensitive to pyrolysis conditions than Western shale.

Burnham, A.K.; Coburn, T.T.; Richardson, J.H.

1982-08-01T23:59:59.000Z

431

Reconciling competing models: a case study of wine fermentation kinetics  

Science Conference Proceedings (OSTI)

Mathematical models of wine fermentation kinetics promise early diagnosis of stuck or sluggish winemaking processes as well as better matching of industrial yeast strains to specific vineyards. The economic impact of these challenges is significant: ... Keywords: combined and refined model, fermentation problems, mechanistic kinetic models, statistical comparison with experimental data, wine fermentation

Rodrigo Assar; Felipe A. Vargas; David J. Sherman

2010-07-01T23:59:59.000Z

432

Solubilty and growth kinetics of silver nitrate in ethanol  

Science Conference Proceedings (OSTI)

The solubility of silver nitrate in ethanol was determined at various temperatures. The growth kinetics of silver nitrate in ethanol were then determined using initial derivaties of temperature and desupersaturation in a mixed-batch crystallizer. For ... Keywords: ethanol, growth kinetics, initial derivatives, silver nitrate, solubility

M. Manteghian; A. Ebrahimi

2002-08-01T23:59:59.000Z

433

Presidential Policy Directive / PPD-8 National Preparedness  

Science Conference Proceedings (OSTI)

... Homeland Security Presidential Directives, National Security Presidential Directives, and national ... days from the date of this directive, the Secretary ...

2011-10-20T23:59:59.000Z

434

REACTION KINETICS AND X-RAY ABSORPTION SPECTROSCOPY STUDIES OF YTTRIUM CONTAINING METAL HYDRIDE ELECTRODES  

DOE Green Energy (OSTI)

This was a study of electrode degradation mechanisms and the reaction kinetics of LaNi{sub 4.7}Sn{sub 0.3}, La{sub (1{minus}x)}, (x = 0.1, 0.2, and 0.3) and La{sub 0.7}Y{sub 0.3}Ni{sub 4.6}Sn{sub 0.3}Co{sub 0.1} metal hydride electrodes. Alloy characterization included x-ray diffraction (XRD), x-ray absorption (XAS), hydrogen absorption in a Sieverts apparatus, and electrochemical cycling of alloy electrodes. The atomic volume of H was determined for two of the alloys. Electrochemical kinetic measurements were made using steady state galvanostatic measurements, galvanodynamic sweep, and electrochemical impedance techniques. XAS was used to examine the degree of corrosion of the alloys with cycling. Alloying with Y decreased the corrosion rate. The results are consistent with corrosion inhibition by a Y containing passive film. The increase in the kinetics of the hydrogen oxidation reaction (HOR) with increasing depth of discharge was much greater on the Y containing alloys. This may be due to the dehydriding of the catalytic species on the surface of the metal hydride particles.

TICIANELLI,E.A.; MUKERJEE,S.; MCBREEN,J.; ADZIC,G.D.; JOHNSON,J.R.; REILLY,J.J.

1998-11-01T23:59:59.000Z

435

A Novel Approach to Experimental Studies of Mineral Dissolution Kinetics  

SciTech Connect

Currently, DOE is conducting pilot CO{sub 2} injection tests to evaluate the concept of geological sequestration. The injected CO{sub 2} is expected to react with the host rocks and these reactions can potentially alter the porosity, permeability, and mechanical properties of the host or cap rocks. Reactions can also result in precipitation of carbonate-containing minerals that favorably and permanently trap CO{sub 2} underground. Many numerical models have been used to predict these reactions for the carbon sequestration program. However, a firm experimental basis for predicting silicate reaction kinetics in CO{sub 2} injected geological formations is urgently needed to assure the reliability of the geochemical models used for the assessments of carbon sequestration strategies. The funded experimental and theoretical study attempts to resolve this outstanding scientific issue by novel experimental design and theoretical interpretation of silicate dissolution rates at conditions pertinent to geological carbon sequestration. In this four year research grant (three years plus a one year no cost extension), seven (7) laboratory experiments of CO{sub 2}-rock-water interactions were carried out. An experimental design allowed the collection of water samples during experiments in situ and thus prevented back reactions. Analysis of the in situ samples delineated the temporal evolution of aqueous chemistry because of CO{sub 2}-rock-water interactions. The solid products of the experiments were retrieved at the end of the experimental run, and analyzed with a suite of advanced analytical and electron microscopic techniques (i.e., atomic resolution transmission electron microscopy (TEM), scanning electron microscopy (SEM), electron microprobe, X-ray diffraction, X-ray photoelectron spectroscopy (XPS)). As a result, the research project probably has produced one of the best data sets for CO{sub 2}-rock-water interactions in terms of both aqueous solution chemistry and solid characterization. Three experiments were performed using the Navajo sandstone. Navajo sandstone is geologically equivalent to the Nugget sandstone, which is a target formation for a regional partnership injection project. Our experiments provided the experimental data on the potential CO{sub 2}-rock-water interactions that are likely to occur in the aquifer. Geochemical modeling was performed to interpret the experimental results. Our single mineral (feldspar) experiments addressed a basic research need. i.e., the coupled nature of dissolution and precipitation reactions, which has universal implication to the reaction kinetics as it applied to CO{sub 2} sequestration. Our whole rock experiments (Navajo sandstone) addressed the applied research component, e.g., reacting Navajo sandstone with brine and CO{sub 2} has direct relevance on the activities of a number of regional partnerships. The following are the major findings from this project: (1) The project generated a large amount of experimental data that is central to evaluating CO{sub 2}-water-rock interactions and providing ground truth to predictive models, which have been used and will inevitably be increasingly more used in carbon sequestration. (2) Results from the feldspar experiments demonstrated stronger coupling between dissolution and precipitation reactions. We show that the partial equilibrium assumption did not hold in the feldspar hydrolysis experiments (Zhu and Lu, submitted, Appendix A-2). The precipitation of clay minerals influenced dissolution of primary silicate in a much stronger way as previously envisioned. Therefore, our experimental data indicated a much more complex chemical kinetics as it has been applied to carbon sequestration program in terms of preliminary predictive models of CO{sub 2}-rock-water interactions. Adopting this complexity (strong coupling) may influence estimates of mineral trapping and porosity/permeability for geological carbon sequestration. In general, our knowledge of the coupling of different reactions is poor, and we must consider the uncertainties resultin

Chen Zhu

2008-08-31T23:59:59.000Z

436

Current measurement apparatus  

DOE Patents (OSTI)

Apparatus and methods are provided for a system for measurement of a current in a conductor such that the conductor current may be momentarily directed to a current measurement element in order to maintain proper current without significantly increasing an amount of power dissipation attributable to the current measurement element or adding resistance to assist in current measurement. The apparatus and methods described herein are useful in superconducting circuits where it is necessary to monitor current carried by the superconducting elements while minimizing the effects of power dissipation attributable to the current measurement element.

Umans, Stephen D. (Belmont, MA)

2008-11-11T23:59:59.000Z

437

A KINETIC MODEL OF SOLAR WIND GENERATION BY OBLIQUE ION-CYCLOTRON WAVES  

Science Conference Proceedings (OSTI)

The fast solar wind is generated by extended perpendicular ion heating in coronal holes, but the kinetic mechanism responsible for this heating has not been determined. One long-standing possibility is the resonant-cyclotron dissipation of ion-cyclotron waves, replenished from a turbulent cascade of interacting counter-propagating Alfven waves. We present results of a kinetic model for proton heating by the quasilinear resonant-cyclotron wave-particle interaction in a coronal hole. The resonant wave spectrum is taken as a power law in wavenumber, uniformly distributed in propagation direction between 0 deg. and 60 deg. with respect to the large-scale radial magnetic field. We obtain the steady-state solution of the kinetic guiding-center equation for the proton distribution in an expanding coronal hole, including the effects of large-scale forces of gravity, charge-separation electric field, Alfven wave ponderomotive force, and mirror force, along with the small-scale scattering from the wave dissipation. We find that plausible wave intensities can yield reasonable flow speeds and temperatures in the heliocentric radial range between 2 and 6 solar radii. We address the claim in earlier work that dissipation of parallel-propagating ion-cyclotron waves cannot provide enough acceleration and show that claim to be incorrect. We find that the combined action of the large-scale forces and the resonant-cyclotron scattering produces proton distribution functions with a characteristic structure: compressed in the sunward half of velocity space with a high-density shell separate from the origin, and relatively expanded in the anti-sunward half of velocity space. We suggest that qualitatively similar proton distributions would result from the kinetic evolution of any sufficiently effective perpendicular heating mechanism operating in an expanding coronal hole.

Isenberg, Philip A.; Vasquez, Bernard J. [Institute for the Study of Earth, Oceans and Space and Department of Physics, University of New Hampshire, Durham, NH 03824 (United States)

2011-04-20T23:59:59.000Z

438

Jozso's Legacy Chemical and Kinetic Freeze-out in Heavy-Ion Collisions  

E-Print Network (OSTI)

We review J. Zimanyi's key contributions to the theoretical understanding of dynamical freeze-out in nuclear collisions and their subsequent applications to ultra-relativistic heavy-ion collisions, leading to the discovery of a freeze-out hierarchy where chemical freeze-out of hadron yields precedes the thermal decoupling of their momentum spectra. Following Zimanyi's lines of reasoning we show that kinetic freeze-out necessarily leads to a dependence of the corresponding freeze-out temperature on collision centrality. This centrality dependence can be predicted within hydrodynamic models, and for Au+Au collisions at RHIC this prediction is shown to reproduce the experimentally observed centrality dependence of the thermal decoupling temperature, extracted from hadron momentum spectra. The fact that no such centrality dependence is observed for the chemical decoupling temperature, extracted from the hadron yields measured in these collisions, excludes a similar kinetic interpretation of the chemical decouplin...

Heinz, U

2008-01-01T23:59:59.000Z

439

Influence of the Richtmyer-Meshkov instability on the kinetic energy spectrum.  

Science Conference Proceedings (OSTI)

The fluctuating kinetic energy spectrum in the region near the Richtmyer-Meshkov instability (RMI) is experimentally investigated using particle image velocimetry (PIV). The velocity field is measured at a high spatial resolution in the light gas to observe the effects of turbulence production and dissipation. It is found that the RMI acts as a source of turbulence production near the unstable interface, where energy is transferred from the scales of the perturbation to smaller scales until dissipation. The interface also has an effect on the kinetic energy spectrum farther away by means of the distorted reflected shock wave. The energy spectrum far from the interface initially has a higher energy content than that of similar experiments with a flat interface. These differences are quick to disappear as dissipation dominates the flow far from the interface.

Weber, Christopher R. (University of Wisconsin-Madison, Madison, WI)

2010-09-01T23:59:59.000Z

440

Kinetic Isotope Effects for the Reactions of Muonic Helium and Muonium with H2  

DOE Green Energy (OSTI)

The neutral muonic helium atom may be regarded as the heaviest isotope of the hydrogen atom, with a mass of ~4.1 amu (4.1H), because the negative muon screens one proton charge. We report the reaction rate of 4.1H with 1H2 to produce 4.1H1H + 1H at 295 to 500 K. The experimental rate constants are compared with the predictions of accurate quantum mechanical dynamics calculations carried out on an accurate Born-Huang potential energy surface and with previously measured rate constants of 0.11H (where 0.11H is shorthand for muonium). Kinetic isotope effects can be compared for the unprecedentedly large mass ratio of 36. The agreement with accurate quantum dynamics is quantitative at 500 K, and variational transition state theory is used to interpret the extremely low (large inverse) kinetic isotope effects in the 10-4 to 10-2 range.

Fleming, Donald G.; Arseneau, Donald J.; Sukhorukov, Oleksandr; Brewer, Jess H.; Mielke, Steven L.; Schatz, George C.; Garrett, Bruce C.; Peterson, Kirk A.; Truhlar, Donald G.

2011-01-28T23:59:59.000Z

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441

Detailed Chemical Kinetic Reaction Mechanism for Biodiesel Components Methyl Stearate and Methyl Oleate  

DOE Green Energy (OSTI)

New chemical kinetic reaction mechanisms are developed for two of the five major components of biodiesel fuel, methyl stearate and methyl oleate. The mechanisms are produced using existing reaction classes and rules for reaction rates, with additional reaction classes to describe other reactions unique to methyl ester species. Mechanism capabilities were examined by computing fuel/air autoignition delay times and comparing the results with more conventional hydrocarbon fuels for which experimental results are available. Additional comparisons were carried out with measured results taken from jet-stirred reactor experiments for rapeseed methyl ester fuels. In both sets of computational tests, methyl oleate was found to be slightly less reactive than methyl stearate, and an explanation of this observation is made showing that the double bond in methyl oleate inhibits certain low temperature chain branching reaction pathways important in methyl stearate. The resulting detailed chemical kinetic reaction mechanism includes more approximately 3500 chemical species and more than 17,000 chemical reactions.

Naik, C; Westbrook, C K; Herbinet, O; Pitz, W J; Mehl, M

2010-01-22T23:59:59.000Z

442

Kinetics and dynamics of oxidation reactions involving an adsorbed CO species on bulk and supported platinum and copper-oxide  

DOE Green Energy (OSTI)

The proposed research is an integrated experimental and modeling study of oxidation reactions involving CO as a key player -- be it a reactant, adsorbed intermediate, and/or partial oxidation product -- in the catalytic sequence and chemistry. The reaction systems of interest in the project include CO, formaldehyde, and methanol oxidation by O{sub 2} and CO oxidation by NO, on both Pt and copper oxide catalysts. These reactions are of importance in automobile exhaust catalysis. There is a paucity of rate data in the literature for these important environmental control reactions. The goal of this research is to better understand the catalytic chemistry and kinetics of oxidations reactions involving CO as an adsorbed intermediate. Successfully meeting this goal requires an integration of basic kinetic measurements, in situ catalyst surface monitoring, kinetic modeling, and nonlinear mathematical tools.

Harold, M.P.

1991-07-01T23:59:59.000Z

443

A Detailed Chemical Kinetic Reaction Mechanism for Oxidation of Four Small Alkyl Esters in Laminar Premixed Flames  

Science Conference Proceedings (OSTI)

A detailed chemical kinetic reaction mechanism has been developed for a group of four small alkyl ester fuels, consisting of methyl formate, methyl acetate, ethyl formate and ethyl acetate. This mechanism is validated by comparisons between computed results and recently measured intermediate species mole fractions in fuel-rich, low pressure, premixed laminar flames. The model development employs a principle of similarity of functional groups in constraining the H atom abstraction and unimolecular decomposition reactions in each of these fuels. As a result, the reaction mechanism and formalism for mechanism development are suitable for extension to larger oxygenated hydrocarbon fuels, together with an improved kinetic understanding of the structure and chemical kinetics of alkyl ester fuels that can be extended to biodiesel fuels. Variations in concentrations of intermediate species levels in these flames are traced to differences in the molecular structure of the fuel molecules.

Westbrook, C K; Pitz, W J; Westmoreland, P R; Dryer, F L; Chaos, M; Osswald, P; Kohse-Hoinghaus, K; Cool, T A; Wang, J; Yang, B; Hansen, N; Kasper, T

2008-02-08T23:59:59.000Z

444

Kinetics of an Inverse Temperature Transition Process and Its Application on Supported Lipid Bilayer  

E-Print Network (OSTI)

This dissertation focuses on the study of inverse temperature transition processes of the poly(N-isopropylacrylamide) (PNIPAM) and the elastin-like polypeptides (ELPs). A novel temperature jump microfluidic system is introduced and this system shows the ability to measure the kinetics of the PNIPAM and the ELPs collapse without a heat transfer problem. The conformational change of the ELPs during the phase transition process is utilized as a nanoscale protein filter to modulate ligandreceptor binding events on supported lipid bilayers (SLBs). This research study is divided into three main parts. The first part is the development of the temperature jump microfluidics. The kinetics of PNIPAM collapse is used as a model system to show the capability of this new device to measure millisecond time scale phase transition processes. The effects of salts on the kinetics of PNIPAM collapse are also shown in this part. To our knowledge, this is the first study which shows the effects of salts on PNIPAM collapse kinetics. The second part of this research is the application of the novel temperature jump microfluidics. The hydrophobic collapse of ELPs composed of identical sequence but different chain length is investigated. By controlling the molecular weight of the ELPs, the thermodynamic contributions from intermolecular hydrophobic interactions, and intramolecular hydrophobic interactions could be calculated individually for this unique system. The third part is the application of the phase transition property of ELPs. The ELPs are conjugated on the surface of the SLBs as a nanoscale protein filter. The conformation of the ELPs can be modulated by ionic strength of the buffer solution or ambient temperature. The ELPs conjugated SLBs platform showed the ability to block IgG binding to biotin conjugated on the SLBs when the ELPs were in the extended coil state and open the access for protein to bind to biotin in compact globule conformation.

Chang, Chin-Yuan

2010-08-01T23:59:59.000Z

445

Direct Imaging of Nanoscale Dissolution of Dicalcium Phosphate Dihydrate by an Organic Ligand: Concentration Matters  

SciTech Connect

Unraveling the kinetics and mechanisms of sparingly soluble calcium orthophosphate (Ca!P) dissolution in the presence of organic acids at microscopic levels is important for an improved understanding in determining the effectiveness of organic acids present in most rhizosphere environments. Herein, we use in situ atomic force microscopy (AFM) coupled with a fluid reaction cell to image dissolution on the (010) face of brushite, CaHPO4 2H2O, in citrate- bearing solutions over a broad concentration range. We directly measure the dependence of molecular step retreat rate on citrate concentration at various pH values and ionic strengths, relevant to soil solution conditions. We find that low concentrations of citrate(10!100 M)inducedareductioninstepretreatratesalongboththe[10 0]Ccand[101] Ccdirections.However,at higher concentrations (exceeding 0.1 mM), this inhibitory effect was reversed with step retreat speeds increasing rapidly. These results demonstrate that the concentration-dependent modulation of nanoscale Ca!P phase dissolution by citrate may be applied to analyze the controversial role of organic acids in enhancing Ca!P mineral dissolution in a more complex rhizosphere environment. These in situ observations may contribute to resolving the previously unrecognized interactions of root exudates (low molecular weight organic acids) and sparingly soluble Ca!P minerals.

Qin, Lihong [Huazhong Agricultural University, China] [Huazhong Agricultural University, China; Zhang, Wenjun [Huazhong Agricultural University, China] [Huazhong Agricultural University, China; Lu, Jianwei [Huazhong Agricultural University, China] [Huazhong Agricultural University, China; Stack, Andrew G [ORNL] [ORNL; Wang, Lijun [Huazhong Agricultural University, China] [Huazhong Agricultural University, China

2013-01-01T23:59:59.000Z

446

NREL: Learning - Geothermal Direct Use  

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

Direct Use Direct Use Photo of alligators on a farm. Geothermally heated waters allow alligators to thrive on a farm in Colorado, where temperatures can drop below freezing. Geothermal reservoirs of hot water, which are found a few miles or more beneath the Earth's surface, can be used to provide heat directly. This is called the direct use of geothermal energy. Geothermal direct use has a long history, going back to when people began using hot springs for bathing, cooking food, and loosening feathers and skin from game. Today, hot springs are still used as spas. But there are now more sophisticated ways of using this geothermal resource. In modern direct-use systems, a well is drilled into a geothermal reservoir to provide a steady stream of hot water. The water is brought up through

447

CURRENT SHEETS AND COLLISIONLESS DAMPING IN KINETIC PLASMA TURBULENCE  

SciTech Connect

We present the first study of the formation and dissipation of current sheets at electron scales in a wave-driven, weakly collisional, three-dimensional kinetic turbulence simulation. We investigate the relative importance of dissipation associated with collisionless damping via resonant wave-particle interactions versus dissipation in small-scale current sheets in weakly collisional plasma turbulence. Current sheets form self-consistently from the wave-driven turbulence, and their filling fraction is well correlated to the electron heating rate. However, the weakly collisional nature of the simulation necessarily implies that the current sheets are not significantly dissipated via Ohmic dissipation. Rather, collisionless damping via the Landau resonance with the electrons is sufficient to account for the measured heating as a function of scale in the simulation, without the need for significant Ohmic dissipation. This finding suggests the possibility that the dissipation of the current sheets is governed by resonant wave-particle interactions and that the locations of current sheets correspond spatially to regions of enhanced heating.

TenBarge, J. M.; Howes, G. G., E-mail: jason-tenbarge@uiowa.edu [Department of Physics and Astronomy, University of Iowa, Iowa City, IA 52242 (United States)

2013-07-10T23:59:59.000Z

448

Quality Assurance: Policy and Directives  

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

Policy and Directives The Office of Quality Assurance is responsible for DOE's quality assurance (QA) policy and requirements, and for providing assistance with QA implementation....

449

DOE Directives | Department of Energy  

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

Reports Calendar Year Reports Recovery Act Peer Reviews DOE Directives Performance Strategic Plan Testimony Financial Statements Semiannual Reports Work Plan Mission About Us...

450

Direct cooled power electronics substrate  

DOE Patents (OSTI)

The disclosure describes directly cooling a three-dimensional, direct metallization (DM) layer in a power electronics device. To enable sufficient cooling, coolant flow channels are formed within the ceramic substrate. The direct metallization layer (typically copper) may be bonded to the ceramic substrate, and semiconductor chips (such as IGBT and diodes) may be soldered or sintered onto the direct metallization layer to form a power electronics module. Multiple modules may be attached to cooling headers that provide in-flow and out-flow of coolant through the channels in the ceramic substrate. The modules and cooling header assembly are preferably sized to fit inside the core of a toroidal shaped capacitor.

Wiles, Randy H. (Powell, TN), Wereszczak, Andrew A. (Oak Ridge, TN); Ayers, Curtis W. (Kingston, TN); Lowe, Kirk T. (Knoxville, TN)

2010-09-14T23:59:59.000Z

451

Kinetics and mechanisms of the reactions of alkyl radicals with oxygen and with complexes of Co(III), Ru(III), and Ni(III)  

Science Conference Proceedings (OSTI)

The kinetics of the reactions of C{sub 2}H{sub 5} radical with Co(NH{sub 3}){sub 5}X{sup 2+}, Ru(NH{sub 3}){sub 5}X{sup 2+}, and Co(dmgH){sub 2} (X) (Y) (X = Br, Cl, N{sub 3}, SCN; Y = H{sub 2}O, CH{sub 3}CN) complexes were studied using laser flash photolysis of ethylcobalt complexes. The kinetics were obtained by the kinetic probe method. Some relative rate constants were also determined by a competition method based on ethyl halide product ratios. The kinetics of colligation reactions of a series of alkyl radicals with {beta}-Ni(cyclam){sup 2+} were studied using flaser flash photolysis of alkylcobalt complexes. Again, the kinetics were obtained by employing the kinetic probe competition method. The kinetics of the unimolecular homolysis of a series of RNi(cyclam)H{sub 2}O{sup 2+} were studied. Activation parameters were obtained for the unimolecular homolysis of C{sub 2}H{sub 5}Ni(cyclam)H{sub 2}O{sup 2+}. Kinetic and thermodynamic data obtained from these reactions were compared with those for the {sigma}-bonded organometallic complexes. The kinetics of the unimolecular homolysis of a series of RNi(cyclam)H{sub 2}O{sup 2+} complexes were studied by monitoring the formation of the oxygen insertion product RO{sub 2}Ni(cyclam)H{sub 2}O{sup 2+}. The higher rate constants for the reactions of alkyl radicals with oxygen in solution, as compared with those measured in the gas phase, were discussed. 30 refs.

Kelley, D.

1990-10-08T23:59:59.000Z

452

Reaction Kinetics of CO2 Carbonation with Mg-Rich Minerals  

SciTech Connect

Due to their low price, wide availability, and stability of the resulting carbonates, Mg-rich minerals are promising materials for carbonating CO{sub 2}. Direct carbonation of CO{sub 2} with Mg-rich minerals reported in this research for the first time could be considerably superior to conventional liquid extraction processes from an energy consumption perspective due to its avoidance of the use of a large amount of water with high specific heat capacity and latent heat of vaporization. Kinetic models of the reactions of the direct CO{sub 2} carbonation with Mg-rich minerals and within simulated flue gas environments are important to the scale-up of reactor designs. Unfortunately, such models have not been made available thus far. This research was initiated to fill that gap. Magnesium silicate (Mg{sub 2}SiO{sub 4}), a representative compound in Mg-rich minerals, was used to study CO{sub 2} carbonation reaction kinetics under given simulated flue gas conditions. It was found that the chosen sorbent deactivation model fits well the experimental data collected under given conditions. A reaction order of 1 with respect to CO{sub 2} is obtained from experimental data. The Arrhenius form of CO{sub 2} carbonation with Mg{sub 2}SiO{sub 4} is established based on changes in the rate constants of the chosen deactivation model as a function of temperature.

Kwon, Dr. Soonchul [Georgia Institute of Technology; Fan, Maohong [University of Wyoming, Laramie; DaCosta, Dr. Herbert F.M. [Chem-Innovations Inc; Russell, Dr. Armistead [Georgia Institute of Technology; Tsouris, Costas [ORNL

2011-01-01T23:59:59.000Z

453

Morphology and non-isothermal crystallization kinetics of CuInS{sub 2} nanocrystals synthesized by solvo-thermal method  

Science Conference Proceedings (OSTI)

Nanocrystals of copper indium disulphide (CuInS{sub 2}) were synthesized by a solvo-thermal method. The structure, morphology and non-isothermal crystallization kinetic behavior of samples were investigated using X-ray diffraction, field emission scanning electron microscopy, field emission transmission electron microscopy, thermogravimetric analysis and differential thermal analysis techniques. Non-isothermal measurements at different heating rates were carried out and the crystallization kinetics of samples were analyzed using the most reliable non-isothermal kinetic methods. The kinetic parameters such as glass transition temperature, thermal stability, activation energy, Avrami exponent etc. were evaluated. - Highlights: Black-Right-Pointing-Pointer CuInS{sub 2} nanocrystals have scientific and technological importance. Black-Right-Pointing-Pointer Samples have been prepared by solvo-thermal method. Black-Right-Pointing-Pointer Synthesized samples exhibit excellent morphology and thermal properties. Black-Right-Pointing-Pointer Investigated properties may be utilized in design and fabrication of solar cell devices.

Majeed Khan, M.A., E-mail: majeed_phys@yahoo.co.in [King Abdullah Institute for Nanotechnology, King Saud University, Riyadh 11451 (Saudi Arabia); Kumar, Sushil [Department of Physics, Chaudhary Devi Lal University, Sirsa 125055 (India); Alsalhi, M.S. [King Abdullah Institute for Nanotechnology, King Saud University, Riyadh 11451 (Saudi Arabia); Department of Physics and Astronomy, King Saud University, Riyadh 11451 (Saudi Arabia); Ahamed, Maqusood [King Abdullah Institute for Nanotechnology, King Saud University, Riyadh 11451 (Saudi Arabia); Alhoshan, Mansour [King Abdullah Institute for Nanotechnology, King Saud University, Riyadh 11451 (Saudi Arabia); Chemical Engineering Department, King Saud University, Riyadh 11451 (Saudi Arabia); Alrokayan, Salman A. [King Abdullah Institute for Nanotechnology, King Saud University, Riyadh 11451 (Saudi Arabia); Ahamad, Tansir [Department of Chemistry, King Saud University, Riyadh 11451 (Saudi Arabia)

2012-03-15T23:59:59.000Z

454

Interpretation of Surface and Planetary Directional Albedos for Vegetated Regions  

Science Conference Proceedings (OSTI)

An atmospheric solar radiation model has been coupled with surface reflectance measurements for two vegetation types, pasture land and savannah, in order to address several issues associated with understanding the directional planetary albedo; ...

Inna L. Vulis; Robert D. Cess

1989-09-01T23:59:59.000Z

455

Direct Sampling of Entrainment Events in a Marine Stratocumulus Layer  

Science Conference Proceedings (OSTI)

Entrainment mixing and the stability of a marine stratocumulus layer are investigated using aircraft data gathered during the FIRE marine stratocumulus experiment. Direct measurement of entrainment events is accomplished through conditional ...

Siri Jodha S. Khalsa

1993-06-01T23:59:59.000Z

456

Direct photons ~basis for characterizing heavy ion collisions~  

E-Print Network (OSTI)

After years of experimental and theoretical efforts, direct photons become a strong and reliable tool to establish the basic characteristics of a hot and dense matter produced in heavy ion collisions. The recent direct photon measurements are reviewed and a future prospect is given.

Takao Sakaguchi

2008-05-30T23:59:59.000Z

457

ARM - Measurements  

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

Select below to highlight measurements in specified measurement categories. Aerosols The effect of aerosols is measured by instrument systems and lidars that provide data...

458

Kinetics of the reactions of hydrogen fluoride with calcium oxide  

Science Conference Proceedings (OSTI)

This paper studies the kinetics of interaction of gaseous hydrogen fluoride with calcium oxide at temperatures 300-700 degrees. The experiments were conducted in a laboratory adsorption apparatus modified and adapted for work with corrosive hydrogen fluoride. Calcium oxide samples in granulated form and deposited on gamma-alumina were used in the experiments. Kinetic curves representing variations of the degree of conversion of the solid samples with time are shown. The influence of retardation dure to diffusion was observed in the experiments. The influence of diffusion control on the reaction rate was also observed in a study of the reaction kinetics on supported layers of calcium oxide.

Kossaya, A.M.; Belyakov, B.P.; Kuchma, Z.V.; Sandrozd, M.K.; Vasil'eva, V.G.

1986-08-01T23:59:59.000Z

459

Evidence of critical balance in kinetic Alfven wave turbulence simulations  

Science Conference Proceedings (OSTI)

A numerical simulation of kinetic plasma turbulence is performed to assess the applicability of critical balance to kinetic, dissipation scale turbulence. The analysis is performed in the frequency domain to obviate complications inherent in performing a local analysis of turbulence. A theoretical model of dissipation scale critical balance is constructed and compared to simulation results, and excellent agreement is found. This result constitutes the first evidence of critical balance in a kinetic turbulence simulation and provides evidence of an anisotropic turbulence cascade extending into the dissipation range. We also perform an Eulerian frequency analysis of the simulation data and compare it to the results of a previous study of magnetohydrodynamic turbulence simulations.

TenBarge, J. M.; Howes, G. G. [Department of Physics and Astronomy, University of Iowa, Iowa City, Iowa 52242 (United States)

2012-05-15T23:59:59.000Z

460

ROLES OF THE KINETIC AND DYNAMIC MECHANISMS IN THE L{sub p} -E{sub p} RELATION  

SciTech Connect

The L{sub p} -E{sub p} relation is a well-known relation in gamma-ray bursts (GRBs). Its implication remains unclear. We propose to investigate the underlying mechanisms of this relation by considering the corresponding kinetic and dynamic mechanisms separately. In this way, one can tell how much the kinetic or dynamic mechanism contributes to the index of the relationship. Our analysis gives rise to several conclusions. (1) The index of the kinetic effect in the L{sub p} -E{sub p} relation can simply be derived from the theory of special relativity, which is generally larger than 2, depending on the situation concerned. (2) The index of the dynamic effect in the relation can be deduced from observation once a model of jets is adopted. According to current GRB data, we find that the dynamic effect alone tends to give rise to an anti-correlation between L{sub p} and E{sub p} ; in terms of statistics, the dynamic effect is obviously smaller than the kinetic effect; in the situation of jets with moving discrete radio clouds that move directly toward the observer, the index of the dynamic effect is currently constrained within (- 1.6, -1), while in other situations of jets, the constraints are different; both internal and external shocks can account for the current data.

Qin, Yi-Ping; Chen, Zhi-Fu, E-mail: ypqin@gzhu.edu.cn [Center for Astrophysics, Guangzhou University, Guangzhou 510006 (China)] [Center for Astrophysics, Guangzhou University, Guangzhou 510006 (China)

2013-04-10T23:59:59.000Z