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1

Advancing Reactive Tracer Methods for Measuring Thermal Evolution in CO2-  

Open Energy Info (EERE)

Advancing Reactive Tracer Methods for Measuring Thermal Evolution in CO2- Advancing Reactive Tracer Methods for Measuring Thermal Evolution in CO2- and Water-Based Geothermal Reservoirs Geothermal Lab Call Project Jump to: navigation, search Last modified on July 22, 2011. Project Title Advancing Reactive Tracer Methods for Measuring Thermal Evolution in CO2- and Water-Based Geothermal Reservoirs Project Type / Topic 1 Laboratory Call for Submission of Applications for Research, Development and Analysis of Geothermal Technologies Project Type / Topic 2 Tracers and Tracer Interpretation Project Description The concepts and theory behind the use of heat-sensitive tracers to study the thermal evolution of geothermal reservoirs was developed in the late 1980's under the Hot Dry Rock Project. Those studies described-conceptually and mathematically-the application of reactive tracers to tracking thermal fronts and to reservoir sizing. Later mathematical treatments focused on application of a single reactive tracer test to recover the temperature profile of a single streamtube. Previous tracer work has mainly focused on identifying conservative tracers. In these studies, chemicals that degraded at reservoir temperatures were discarded. Benzoic acids and dicarboxylic acids, which were found by Adams to degrade, may be useful as reactive tracers. Organic esters and amide tracers that undergo hydrolysis have been investigated and their use as reactive tracers appears feasible over a temperature range of 100ºC to 275ºC. However their reaction rates are pH dependent and sorption reactions have not been evaluated. While reactive tracer parameters have been measured in the lab, reactive tracers have not been extensively tested in the field. Thus, while reactive tracers appear to be a promising means of monitoring the thermal evolution of a geothermal reservoir, the concept has yet to be tested at the scale necessary for successful implementation, and tools for analyzing results of such tracer tests under the non-ideal conditions of an actual geothermal system have yet to be developed.

2

Advancing Reactive Tracer Methods for Measurement of Thermal Evolution in Geothermal Reservoirs: Final Report  

SciTech Connect (OSTI)

The injection of cold fluids into engineered geothermal system (EGS) and conventional geothermal reservoirs may be done to help extract heat from the subsurface or to maintain pressures within the reservoir (e.g., Rose et al., 2001). As these injected fluids move along fractures, they acquire heat from the rock matrix and remove it from the reservoir as they are extracted to the surface. A consequence of such injection is the migration of a cold-fluid front through the reservoir (Figure 1) that could eventually reach the production well and result in the lowering of the temperature of the produced fluids (thermal breakthrough). Efficient operation of an EGS as well as conventional geothermal systems involving cold-fluid injection requires accurate and timely information about thermal depletion of the reservoir in response to operation. In particular, accurate predictions of the time to thermal breakthrough and subsequent rate of thermal drawdown are necessary for reservoir management, design of fracture stimulation and well drilling programs, and forecasting of economic return. A potential method for estimating migration of a cold front between an injection well and a production well is through application of reactive tracer tests, using chemical whose rate of degradation is dependent on the reservoir temperature between the two wells (e.g., Robinson 1985). With repeated tests, the rate of migration of the thermal front can be determined, and the time to thermal breakthrough calculated. While the basic theory behind the concept of thermal tracers has been understood for some time, effective application of the method has yet to be demonstrated. This report describes results of a study that used several methods to investigate application of reactive tracers to monitoring the thermal evolution of a geothermal reservoir. These methods included (1) mathematical investigation of the sensitivity of known and hypothetical reactive tracers, (2) laboratory testing of novel tracers that would improve method sensitivity, (3) development of a software tool for design and interpretation of reactive tracer tests and (4) field testing of the reactive tracer temperature monitoring concept.

Mitchell A. Plummer; Carl D. Palmer; Earl D. Mattson; Laurence C. Hull; George D. Redden

2011-07-01T23:59:59.000Z

3

Advancing reactive tracer methods for measuring thermal evolution in CO2-and water-based geothermal reservoirs  

Broader source: Energy.gov [DOE]

DOE Geothermal Peer Review 2010 - Presentation. This project aims to develop reactive tracer method for monitoring thermal drawdown in enhanced geothermal systems.

4

Thermomechanical measurements on thermal microactuators.  

SciTech Connect (OSTI)

Due to the coupling of thermal and mechanical behaviors at small scales, a Campaign 6 project was created to investigate thermomechanical phenomena in microsystems. This report documents experimental measurements conducted under the auspices of this project. Since thermal and mechanical measurements for thermal microactuators were not available for a single microactuator design, a comprehensive suite of thermal and mechanical experimental data was taken and compiled for model validation purposes. Three thermal microactuator designs were selected and fabricated using the SUMMiT V{sup TM} process at Sandia National Laboratories. Thermal and mechanical measurements for the bent-beam polycrystalline silicon thermal microactuators are reported, including displacement, overall actuator electrical resistance, force, temperature profiles along microactuator legs in standard laboratory air pressures and reduced pressures down to 50 mTorr, resonant frequency, out-of-plane displacement, and dynamic displacement response to applied voltages.

Baker, Michael Sean; Epp, David S.; Serrano, Justin Raymond; Gorby, Allen D.; Phinney, Leslie Mary

2009-01-01T23:59:59.000Z

5

Energy Partitions and Evolution in a Purely Thermal Solar Flare  

E-Print Network [OSTI]

This paper presents a solely thermal flare, which we detected in the microwave range from the thermal gyro- and free-free emission it produced. An advantage of analyzing thermal gyro emission is its unique ability to precisely yield the magnetic field in the radiating volume. When combined with observationally-deduced plasma density and temperature, these magnetic field measurements offer a straightforward way of tracking evolution of the magnetic and thermal energies in the flare. For the event described here, the magnetic energy density in the radio-emitting volume declines over the flare rise phase, then stays roughly constant during the extended peak phase, but recovers to the original level over the decay phase. At the stage where the magnetic energy density decreases, the thermal energy density increases; however, this increase is insufficient, by roughly an order of magnitude, to compensate for the magnetic energy decrease. When the magnetic energy release is over, the source parameters come back to ne...

Fleishman, Gregory D; Gary, Dale E

2015-01-01T23:59:59.000Z

6

Measuring 0 using cluster evolution  

Science Journals Connector (OSTI)

......this estimate. An alternative method that uses...this estimate. An alternative method that uses...low-redshift studies car- ried out by Edge...specific galaxy kinetic energy equals the specific gas thermal energy within the virial......

Vincent R. Eke; Shaun Cole; Carlos S. Frenk; J. Patrick Henry

1998-08-21T23:59:59.000Z

7

Measurements of the Thermal Neutron Scattering Kernel  

E-Print Network [OSTI]

Measurements of the Thermal Neutron Scattering Kernel Li (Emily) Liu, Yaron Danon, Bjorn Becker and discussions Problems and Future study Questions #12;3 M. Mattes and J. Keinert, Thermal Neutron Scattering experimental data used was from 1973-1974! M. Mattes and J. Keinert, Thermal Neutron Scattering Data

Danon, Yaron

8

Thermal Dosimetry and Temperature Measurements  

Science Journals Connector (OSTI)

...Saptem ber 15 and 16, 1978, San Diego, Calif. 2 The abbreviations used are: RF, radiofrequency; LED, light-emitting diode. gross temperature measurement errors when the probes are used to monitor tissue or phantom material in an electromag...

D. A. Christensen

1979-06-01T23:59:59.000Z

9

Statistical theory of thermal evolution of neutron stars  

E-Print Network [OSTI]

Thermal evolution of neutron stars is known to depend on the properties of superdense matter in neutron star cores. We suggest a statistical analysis of isolated cooling middle-aged neutron stars and old transiently accreting quasi-stationary neutron stars warmed up by deep crustal heating in low-mass X-ray binaries. The method is based on simulations of the evolution of stars of different masses and on averaging the results over respective mass distributions. This gives theoretical distributions of isolated neutron stars in the surface temperature--age plane and of accreting stars in the photon thermal luminosity--mean mass accretion rate plane to be compared with observations. This approach permits to explore not only superdense matter but also the mass distributions of isolated and accreting neutron stars. We show that the observations of these stars can be reasonably well explained by assuming the presence of the powerful direct Urca process of neutrino emission in the inner cores of massive stars, introd...

Beznogov, M V

2014-01-01T23:59:59.000Z

10

Quasi-static thermal evolution of compact objects  

E-Print Network [OSTI]

We study under what conditions the thermal peeling is present for dissipative local and quasi-local anisotropic spherical matter configurations. The thermal peeling occurs when different signs in the velocity of fluid elements appears, giving rise to the splitting of the matter configuration. The evolution is considered in the quasi-static approximation and the matter contents are radiant, anisotropic (unequal stresses) spherical local and quasi-local fluids. The heat flux and the associated temperature profiles are described by causal thermodynamics consistent with this approximation. It is found some particular, local and quasi-local equation of state for ultra-dense matter configurations exhibit thermal peeling when most of the radiated energy is concentrated at the middle of the distribution. This effect, which appears to be associated with extreme astrophysical scenarios (highly relativistic and very luminous gravitational system expelling its outer mass shells), is very sensible to energy flux profile and to the shape of the luminosity emitted by the compact object.

L. Becerra; H. Hernandez; L. A. Nunez

2014-06-22T23:59:59.000Z

11

Report on workshop on thermal property measurements  

SciTech Connect (OSTI)

Results of thermogravimetric analysis of basalt is discussed. Heat capacity, thermal conductivity and thermal expansion are specifically addressed. (CBS)

Robertson, E.C.

1987-01-01T23:59:59.000Z

12

Thermal evolution of neutron stars with global and local neutrality  

E-Print Network [OSTI]

Globally neutral neutron stars, obtained from the solution of the called Einstein-Maxwell-Thomas-Fermi equations that account for all the fundamental interactions, have been recently introduced. These configurations have a more general character than the ones obtained with the traditional Tolman-Oppenheimer-Volkoff, which impose the condition of local charge neutrality. The resulting configurations have a less massive and thinner crust, leading to a new mass-radius relation. Signatures of this new structure of the neutron star on the thermal evolution might be a potential test for this theory. We compute the cooling curves by integrating numerically the energy balance and transport equations in general relativity, for globally neutral neutron stars with crusts of different masses and sizes, according to this theory for different core-crust transition interfaces. We compare and contrast our study with known results for local charge neutrality. We found a new behavior for the relaxation time, depending upon the...

de Carvalho, S M; Rueda, Jorge A; Ruffini, Remo

2014-01-01T23:59:59.000Z

13

Measurement of thermal conductivity P t BPart B  

E-Print Network [OSTI]

wave Take the Fourier transform of this frequency domain solution #12;For a low thermal conductivity thin filmFor a low thermal conductivity thin film on a high thermal conductivity substrate (Factor of 2Measurement of thermal conductivity Part A: P t BPart B: · Time domain thermoreflectance #12

Braun, Paul

14

Morphological Evolution of Thermal Plumes in Turbulent Rayleigh-Bnard Convection  

Science Journals Connector (OSTI)

An experimental study of the morphological evolution of thermal plumes in turbulent thermal convection is presented. Individual sheetlike plumes are extracted and their area, circumference, and heat content are found to all exhibit log-normal distributions. As the sheetlike plumes move across the plate they collide and convolute into spiraling swirls. These swirls then spiral away from the plates to become mushroomlike plumes which are accompanied by strong vertical vorticity. The measured profiles of plume numbers and of vertical vorticity quantify the morphological transition of sheetlike plumes to mushroomlike ones and the mixing and merging or clustering of mushroomlike plumes. The fluctuating vorticity is found to have the same exponential distribution and scaling behavior as the fluctuating temperature.

Quan Zhou; Chao Sun; Ke-Qing Xia

2007-02-12T23:59:59.000Z

15

Marketing performance measurement: evolution of research and practice  

Science Journals Connector (OSTI)

This article reviews the evolution of marketing performance measurement from both research and practitioner perspectives. We find four historical research stages that have evolved in sequence but now continue concurrently, and explore how firms evolve their use of marketing performance measures. Practitioners increasingly regard effectiveness as more important than efficiency in marketing performance. The paper extrapolates that evolution to suggest future directions for practitioners. Identifying the impact of performance measurement systems over time is a critical issue for both research and improved practice.

Bruce H. Clark; Tim Ambler

2001-01-01T23:59:59.000Z

16

Thermal Behavior of As-Recovered (Unneutralized) Aspigel (Pressure Measurements)  

SciTech Connect (OSTI)

This brief report provides unreported pressures measured in accelerating rate calorimeter experiments performed to determine the thermal sensitivity of as-recovered and unneutralized Aspigel.

Scheele, Randall D.

2010-07-02T23:59:59.000Z

17

A simplified model for thermal-wave cavity self-consistent measurement of thermal diffusivity  

SciTech Connect (OSTI)

A simplified theoretical model was developed for the thermal-wave cavity (TWC) technique in this study. This model takes thermal radiation into account and can be employed for absolute measurements of the thermal diffusivity of gas and liquid samples without any knowledge of geometrical and thermal parameters of the components of the TWC. Using this model and cavity-length scans, thermal diffusivities of air and distilled water were accurately and precisely measured as (2.191 0.004) 10{sup ?5} and (1.427 0.009) 10{sup ?7} m{sup 2}?s{sup ?1}, respectively, in very good agreement with accepted literature values.

Shen, Jun, E-mail: jun.shen@nrc-cnrc.gc.ca; Zhou, Jianqin; Gu, Caikang [Energy, Mining and Environment Portfolio, National Research Council Canada, 4250 East Mall, Vancouver, British Columbia V6T 1W5 (Canada)] [Energy, Mining and Environment Portfolio, National Research Council Canada, 4250 East Mall, Vancouver, British Columbia V6T 1W5 (Canada); Neill, Stuart [Energy, Mining and Environment Portfolio, National Research Council Canada, 1200 Montreal Road, Building M-9, Ottawa, Ontario K1A 0R6 (Canada)] [Energy, Mining and Environment Portfolio, National Research Council Canada, 1200 Montreal Road, Building M-9, Ottawa, Ontario K1A 0R6 (Canada); Michaelian, Kirk H.; Fairbridge, Craig [CanmetENERGY, Natural Resources Canada, One Oil Drive Patch, Devon, Alberta T9G 1A8 (Canada)] [CanmetENERGY, Natural Resources Canada, One Oil Drive Patch, Devon, Alberta T9G 1A8 (Canada); Astrath, Nelson G. C.; Baesso, Mauro L. [Departamento de Fsica, Universidade Estadual de Maring, Av. Colombo 5790, Maring, Paran 87020-900 (Brazil)] [Departamento de Fsica, Universidade Estadual de Maring, Av. Colombo 5790, Maring, Paran 87020-900 (Brazil)

2013-12-15T23:59:59.000Z

18

Effects of Thermal Exposure and Test Temperature on Structure Evolution and Hardness/Viscosity  

E-Print Network [OSTI]

Effects of Thermal Exposure and Test Temperature on Structure Evolution and Hardness/Viscosity the physical and mechanical properties (i.e., viscosity, flow, and fracture). In some cases, the thermal coating techniques (e.g., high velocity oxygen fuel (HVOF), plasma spray, cold spray, etc.) have been used

Rollins, Andrew M.

19

Camera-based reflectivity measurement for solar thermal applications  

E-Print Network [OSTI]

Tubular receivers for solar thermal power plants, specifically tower plants, are in common use, in plantsCamera-based reflectivity measurement for solar thermal applications John D. Pye1 , Clifford K. Ho2 of the solar-weighted reflectivity of the receiver component in CSP systems. Such reflectivity measurement

20

Front surface thermal property measurements of air plasma spray coatings  

SciTech Connect (OSTI)

A front-surface measurement for determining the thermal properties of thermal barrier coatings has been applied to air plasma spray coatings. The measurement is used to determine all independent thermal properties of the coating simultaneously. Furthermore, with minimal requirements placed on the sample and zero sample preparation, measurements can be made under previously impossible conditions, such as on serviceable engine parts. Previous application of this technique was limited to relatively thin coatings, where a one-dimensional heat transfer model is applied. In this paper, the influence of heat spreading on the measurement of thicker coatings is investigated with the development of a two-dimensional heat transfer model.

Bennett, Ted; Kakuda, Tyler [University of California, Santa Barbara, California 93106-5070 (United States); Kulkarni, Anand [Siemens Energy, Orlando, Florida 32826-2399 (United States)

2009-04-15T23:59:59.000Z

Note: This page contains sample records for the topic "measuring thermal evolution" 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

Measuring the thermal diffusivity in a student laboratory  

E-Print Network [OSTI]

The paper describes a method for measuring the thermal diffusivity of materials having a high thermal conductivity. The apparatus is rather simple and low-cost, being therefore suitable in a laboratory for undergraduate students of engineering schools, where several set-ups are often required. A recurrence numerical approach solves the thermal field in the specimen, which is depending on the thermal diffusivity of its material. The numerical method requires the temperature data from two different positions in the specimen, measured by two thermocouples connected to a temperature logger.

Sparavigna, Amelia Carolina

2012-01-01T23:59:59.000Z

22

Thermal diffusivity measurement system applied to polymers  

Science Journals Connector (OSTI)

In the search for cleaner energy sources the improvement of the efficiency of the actual ones appears as a primary objective. In this way thermoelectric materials which are able to convert wasted heat into electricity are reveal as an interesting way to improve efficiency of car engines for example. Cost-effective energy harvesting from thermoelectric devices requires materials with high electrical conductivities and Seebeck coefficient but low thermal conductivity. Conductive polymers can fulfil these conditions if they are doped appropriately. One of the most promising polymers is Polyaniline. In this work the thermal conductivity of the polyaniline and mixtures of polyaniline with nanoclays has been studied using a new experimental set-up developed in the lab. The novel system is based on the steady-state method and it is used to obtain the thermal diffusivity of the polymers and the nanocomposites.

2012-01-01T23:59:59.000Z

23

Calculation of TMD Evolution for Transverse Single Spin Asymmetry Measurements  

E-Print Network [OSTI]

The Sivers transverse single spin asymmetry (TSSA) is calculated and compared at different scales using the TMD evolution equations applied to previously existing extractions. We apply the Collins-Soper-Sterman (CSS) formalism, using the version recently developed by Collins. Our calculations rely on the universality properties of TMD-functions that follow from the TMD-factorization theorem. Accordingly, the non-perturbative input is fixed by earlier experimental measurements, including both polarized semi-inclusive deep inelastic scattering (SIDIS) and unpolarized Drell-Yan (DY) scattering. It is shown that recent COMPASS measurements are consistent with the suppression prescribed by TMD evolution.

S. Mert Aybat; Alexei Prokudin; Ted C. Rogers

2012-06-27T23:59:59.000Z

24

Temperature measurements using multicolor pyrometry in thermal radiation heating environments  

SciTech Connect (OSTI)

Temperature measurements are important for thermal-structural experiments in the thermal radiation heating environments such as used for thermal-structural stress analyses. This paper describes the use of multicolor pyrometry for the measurements of diffuse surfaces in thermal radiation environments that eliminates the effects of background radiation reflections and unknown emissivities based on a least-squares algorithm. The near-infrared multicolor pyrometer had a spectral range of 11002400 nm, spectrum resolution of 6 nm, maximum sampling frequency of 2 kHz, working distance of 0.6 m to infinity, temperature range of 7001700 K. The pyrometer wavelength response, nonlinear intensity response, and spectral response were all calibrated. The temperature of a graphite sample irradiated by quartz lamps was then measured during heating and cooling using the least-squares algorithm based on the calibrated irradiation data. The experiments show that higher temperatures and longer wavelengths are more suitable for the thermal measurements in the quartz lamp radiation heating system. This analysis provides a valuable method for temperature measurements of diffuse surfaces in thermal radiation environments.

Fu, Tairan, E-mail: trfu@mail.tsinghua.edu.cn [Key Laboratory for Thermal Science and Power Engineering of Ministry of Education, Department of Thermal Engineering, Tsinghua University, Beijing 100084 (China) [Key Laboratory for Thermal Science and Power Engineering of Ministry of Education, Department of Thermal Engineering, Tsinghua University, Beijing 100084 (China); Beijing Key Laboratory of CO2 Utilization and Reduction Technology, Beijing 100084 (China); Liu, Jiangfan; Duan, Minghao; Zong, Anzhou [Key Laboratory for Thermal Science and Power Engineering of Ministry of Education, Department of Thermal Engineering, Tsinghua University, Beijing 100084 (China)] [Key Laboratory for Thermal Science and Power Engineering of Ministry of Education, Department of Thermal Engineering, Tsinghua University, Beijing 100084 (China)

2014-04-15T23:59:59.000Z

25

Femtosecond-tunable measurement of electron thermalization in gold  

Science Journals Connector (OSTI)

Femtosecond electron thermalization in metals was investigated using transient thermomodulation transmissivity and reflectivity. Studies were performed using a tunable multiple-wavelength femtosecond pump-probe technique in optically thin gold films in the low perturbation limit. An IR pump beam is used to heat the electron distribution and changes in electron temperature are measured with a visible probe beam at the d band to Fermi-surface transition. We show that the subpicosecond optical response of gold is dominated by delayed thermalization of the electron gas. This effect is particularly important far off the spectral peak of the reflectivity or transmissivity changes, permitting a direct and sensitive access to the internal thermalization of the electron gas. Using a simple rate-equation model, line-shape analysis of the transient reflectivity and transmissivity indicates a thermalization time of the order of 500 fs. At energies close to the Fermi surface, longer thermalization times ?12 ps are observed. These results are in agreement with a more sophisticated model based on calculations of the electron-thermalization dynamics by numerical solutions of the Boltzmann equation. This model quantitatively describes the measured transient optical response during the full thermalization time of electron gas, of the order of 1.5 ps, and gives new insight into electron thermalization in metals.

C.-K. Sun; F. Valle; L. H. Acioli; E. P. Ippen; J. G. Fujimoto

1994-11-15T23:59:59.000Z

26

Evolution of seismic velocities in heavy oil sand reservoirs during thermal recovery process  

E-Print Network [OSTI]

1 Evolution of seismic velocities in heavy oil sand reservoirs during thermal recovery process localiser la chambre à vapeur. INTRODUCTION [1] Huge quantities of heavy oils (heavy oil, extra heavy oil. Larribau 64018 Pau Cedex, France Oil and Gas Science and Technology 2012, 67 (6), 1029-1039, doi:10

Paris-Sud XI, Université de

27

Thermal evolution of Mercury as constrained by MESSENGER observations  

E-Print Network [OSTI]

observations have constrained the rate of radiogenic heat production via measurement of uranium, thorium melting, consistent with MESSENGER observations of the planet's surface chemistry and geology. Citation, provides cru- cial context for interpreting a planet's geological history [e.g., Schubert et al., 2001

Zuber, Maria

28

Kinetic evolution of the glasma and thermalization in heavy ion collisions  

E-Print Network [OSTI]

In relativistic heavy ion collisions, a highly occupied gluonic matter is created shortly after initial impact, which is in a non-thermal state and often referred to as the Glasma. Successful phenomenology suggests that the glasma evolves rather quickly toward the thermal quark-gluon plasma and a hydrodynamic behavior emerges at very early time $\\sim \\hat{o}(1)$ fm/c. Exactly how such "apparent thermalization" occurs and connects the initial conditions to the hydrodynamic onset, remains a significant challenge for theory as well as phenomenology. We briefly review various ideas and recent progress in understanding the approach of the glasma to the thermalized quark-gluon plasma, with an emphasis on the kinetic theory description for the evolution of such far-from-equilibrium and highly overpopulated, thus weakly-coupled yet strongly interacting glasma.

Xu-Guang Huang; Jinfeng Liao

2014-03-29T23:59:59.000Z

29

Advancing reactive tracer methods for measuring thermal evolution...  

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

et al. (2003) - Use simplified geometry of hypothetical fracture system - Develop in MATLAB, to allow distribution to industry via the MATLAB compiler * Conducted 2-D finite...

30

Thin-film aerogel thermal conductivity measurements via 3?  

Science Journals Connector (OSTI)

The limiting constraint in a growing number of nano systems is the inability to thermally tune devices. Silica aerogel is widely accepted as the best solid thermal insulator in existence and offers a promising solution for microelectronic systems needing superior thermal isolation. In this study, thin-film silica aerogel films varying in thickness from 250 to 1280nm were deposited on SiO2 substrates under a variety of deposition conditions. These samples were then thermally characterized using the 3? technique. Deposition processes for depositing the 3? testing mask to the sample were optimized and it was demonstrated that thin-film aerogel can maintain its structure in common fabrication processes for microelectromechanical systems. Results indicate that thin-film silica aerogel can maintain the unique, ultra-low thermal conductivity commonly observed in bulk aerogel, with a directly measured thermal conductivity as low as 0.024W/m-K at temperature of 295K and pressure between 0.1 and 1Pa.

M.L. Bauer; C.M. Bauer; M.C. Fish; R.E. Matthews; G.T. Garner; A.W. Litchenberger; P.M. Norris

2011-01-01T23:59:59.000Z

31

THE INFLUENCE OF PRESSURE-DEPENDENT VISCOSITY ON THE THERMAL EVOLUTION OF SUPER-EARTHS  

SciTech Connect (OSTI)

We study the thermal evolution of super-Earths with a one-dimensional (1D) parameterized convection model that has been adopted to account for a strong pressure dependence of the viscosity. A comparison with a 2D spherical convection model shows that the derived parameterization satisfactorily represents the main characteristics of the thermal evolution of massive rocky planets. We find that the pressure dependence of the viscosity strongly influences the thermal evolution of super-Earths-resulting in a highly sluggish convection regime in the lower mantles of those planets. Depending on the effective activation volume and for cooler initial conditions, we observe with growing planetary mass even the formation of a conductive lid above the core-mantle boundary (CMB), a so-called CMB-lid. For initially molten planets our results suggest no CMB-lids but instead a hot lower mantle and core as well as sluggish lower mantle convection. This implies that the initial interior temperatures, especially in the lower mantle, become crucial for the thermal evolution-the thermostat effect suggested to regulate the interior temperatures in terrestrial planets does not work for massive planets if the viscosity is strongly pressure dependent. The sluggish convection and the potential formation of the CMB-lid reduce the convective vigor throughout the mantle, thereby affecting convective stresses, lithospheric thicknesses, and heat fluxes. The pressure dependence of the viscosity may therefore also strongly affect the propensity of plate tectonics, volcanic activity, and the generation of a magnetic field of super-Earths.

Stamenkovic, Vlada; Noack, Lena; Spohn, Tilman [Institute of Planetology, Westfaelische Wilhelms-Universitaet Muenster, Wilhelm-Klemm-Str. 10, 48149 Muenster (Germany); Breuer, Doris, E-mail: Vlada.Stamenkovic@dlr.de, E-mail: Lena.Noack@dlr.de, E-mail: Doris.Breuer@dlr.de, E-mail: Tilman.Spohn@dlr.de [Institute of Planetary Research, German Aerospace Center DLR, Rutherfordstrasse 2, 12489 Berlin (Germany)

2012-03-20T23:59:59.000Z

32

The evolution of solid density within a thermal explosion II. Dynamic proton radiography of cracking and solid consumption by burning  

SciTech Connect (OSTI)

We report proton transmission images obtained subsequent to the laser assisted thermal ignition of a sample of PBX 9501 (a plastic bonded formulation of the explosive nitramine octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX)). We describe the laser assisted thermal ignition technique as a means to synchronize a non-linear thermal ignition event while preserving the subsequent post-ignition behavior. We have obtained dynamic proton transmission images at two spatial magnifications and viewed both the radial and transverse axis of a solid cylindrical sample encased in aluminum. Images have been obtained with 3 to 15 {mu}s temporal resolution and approximately 100 {mu}m spatial resolution at the higher magnification. We observe case expansion from very early in the experiment, until case fragmentation. We observe spatially anisotropic features in the transmission which we attribute to cracking in the solid explosive, in agreement with previous measurements conducted on two dimensional samples with optical viewing. Digital analysis of the images also reveals spatially isotropic features which we attribute to the evolution of the loss of density by burning subsequent to thermal ignition.

Smilowitz, L.; Henson, B. F.; Romero, J. J.; Asay, B. W.; Saunders, A.; Merrill, F. E.; Morris, C. L.; Kwiatkowski, K.; Grim, G.; Mariam, F.; Schwartz, C. L.; Hogan, G.; Nedrow, P.; Murray, M. M.; Thompson, T. N.; Espinoza, C.; Lewis, D.; Bainbridge, J.; McNeil, W.; Rightley, P. [Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States); and others

2012-05-15T23:59:59.000Z

33

MEASUREMENT OF WIND SPEED FROM COOLING LAKE THERMAL IMAGERY  

SciTech Connect (OSTI)

The Savannah River National Laboratory (SRNL) collected thermal imagery and ground truth data at two commercial power plant cooling lakes to investigate the applicability of laboratory empirical correlations between surface heat flux and wind speed, and statistics derived from thermal imagery. SRNL demonstrated in a previous paper [1] that a linear relationship exists between the standard deviation of image temperature and surface heat flux. In this paper, SRNL will show that the skewness of the temperature distribution derived from cooling lake thermal images correlates with instantaneous wind speed measured at the same location. SRNL collected thermal imagery, surface meteorology and water temperatures from helicopters and boats at the Comanche Peak and H. B. Robinson nuclear power plant cooling lakes. SRNL found that decreasing skewness correlated with increasing wind speed, as was the case for the laboratory experiments. Simple linear and orthogonal regression models both explained about 50% of the variance in the skewness - wind speed plots. A nonlinear (logistic) regression model produced a better fit to the data, apparently because the thermal convection and resulting skewness are related to wind speed in a highly nonlinear way in nearly calm and in windy conditions.

Garrett, A; Robert Kurzeja, R; Eliel Villa-Aleman, E; Cary Tuckfield, C; Malcolm Pendergast, M

2009-01-20T23:59:59.000Z

34

THERMAL PERFORMANCE MEASUREMENTS ON ULTIMATE HEAT SINKS - COOLING PONDS  

Office of Scientific and Technical Information (OSTI)

THERMAL PERFORMANCE MEASUREMENTS THERMAL PERFORMANCE MEASUREMENTS ON ULTIMATE HEAT SINKS - COOLING PONDS R. K. Hadlock 0 . B. Abbey Battelle Pacific Northwest Laboratories Prepared for U. S. Nuclear Regulatory Commission b + NOTICE This report was prepared as an account of work sponsored by the United States Government. Neither the United States nor the United States Nuclear Regulatory Commission, nor any of their employees, nor any of their contractors, subcontractors, or their employees, makes any warranty, express or implied, nor assumes any legal liability or responsibility for the accuracy, completeness or usefulness of any information, apparatus, pro- duct or process disclosed, nor represents that its use would not infringe privately owned rights. F Available from National Technical Information Service

35

Thermal Imaging Technique for Measuring Mixing of Fluids - Energy...  

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

Solar Thermal Solar Thermal Energy Analysis Energy Analysis Building Energy Efficiency Building Energy Efficiency Find More Like This Return to Search Thermal Imaging Technique for...

36

Evolution of seismic velocities in heavy oil sand reservoirs during thermal recovery process  

E-Print Network [OSTI]

In thermally enhanced recovery processes like cyclic steam stimulation (CSS) or steam assisted gravity drainage (SAGD), continuous steam injection entails changes in pore fluid, pore pressure and temperature in the rock reservoir, that are most often unconsolidated or weakly consolidated sandstones. This in turn increases or decreases the effective stresses and changes the elastic properties of the rocks. Thermally enhanced recovery processes give rise to complex couplings. Numerical simulations have been carried out on a case study so as to provide an estimation of the evolution of pressure, temperature, pore fluid saturation, stress and strain in any zone located around the injector and producer wells. The approach of Ciz and Shapiro (2007) - an extension of the poroelastic theory of Biot-Gassmann applied to rock filled elastic material - has been used to model the velocity dispersion in the oil sand mass under different conditions of temperature and stress. A good agreement has been found between these pre...

Nauroy, Jean-Franois; Guy, N; Baroni, Axelle; Delage, Pierre; Mainguy, Marc; 10.2516/ogst/2012027

2013-01-01T23:59:59.000Z

37

Measuring oxygen reduction/evolution reactions on the nanoscale  

SciTech Connect (OSTI)

The efficiency of fuel cells and metal-air batteries is significantly limited by the activation of oxygen reduction and evolution reactions (ORR/OER). Despite the well-recognized role of oxygen reaction kinetics on the viability of energy technologies, the governing mechanisms remain elusive and until now addressable only by macroscopic studies. This lack of nanoscale understanding precludes optimization of material architecture. Here we report direct measurements of oxygen reduction/evolution reactions and oxygen vacancy diffusion on oxygen-ion conductive solid surfaces with sub-10 nanometer resolution. In electrochemical strain microscopy (ESM), the biased scanning probe microscopy tip acts as a moving, electrocatalytically active probe exploring local electrochemical activity. The probe concentrates an electric field in a nanometer-scale volume of material, and bias-induced, picometer-level surface displacements provide information on local electrochemical processes. Systematic mapping of oxygen activity on bare and Pt-functionalized yttria-stabilized zirconia (YSZ) surfaces is demonstrated. This approach allows directly visualization of ORR/OER activation process at the triple-phase boundary, and can be extended to broad spectrum of oxygen-conductive and electrocatalytic materials.

Kalinin, Sergei V [ORNL; Jesse, Stephen [ORNL; Kumar, Amit [ORNL; Morozovska, A. N. [National Academy of Science of Ukraine, Kiev, Ukraine; Ciucci, Francesco [Harvard-Smithsonian Center for Astrophysics

2011-01-01T23:59:59.000Z

38

The Envelope Thermal Test Unit (ETTU): Full Measurement of Wall Perform ance  

E-Print Network [OSTI]

Energy Conservation in the Built Environment, Dublin, Ireland, March 30-April THE ENVELOPE THERMAL TEST UNIT (ETTU): FIELD MEASUREMENT

Sonderegger, R.C.; Sherman, M.H.; Adams, J.W.

2008-01-01T23:59:59.000Z

39

The Envelope Thermal Test Unit (ETTU): Full Measurement of Wall Perform ance  

E-Print Network [OSTI]

Energy Conservation in the Built Environment, Dublin, Ireland, March 30-April THE ENVELOPE THERMAL TEST UNIT (ETTU): FIELD MEASUREMENT

Adams, J.W.

2010-01-01T23:59:59.000Z

40

Measurement of Thermal Dependencies of PBG Fiber Properties  

SciTech Connect (OSTI)

Photonic crystal fibers (PCFs) represent a class of optical fibers which have a wide spectrum of applications in the telecom and sensing industries. Currently, the Advanced Accelerator Research Department at SLAC is developing photonic bandgap particle accelerators, which are photonic crystal structures with a central defect used to accelerate electrons and achieve high longitudinal electric fields. Extremely compact and less costly than the traditional accelerators, these structures can support higher accelerating gradients and will open a new era in high energy physics as well as other fields of science. Based on direct laser acceleration in dielectric materials, the so called photonic band gap accelerators will benefit from mature laser and semiconductor industries. One of the key elements to direct laser acceleration in hollow core PCFs, is maintaining thermal and structural stability. Previous simulations demonstrate that accelerating modes are sensitive to the geometry of the defect region and the variations in the effective index. Unlike the telecom modes (for which over 95% of the energy propagates in the hollow core) most of the power of these modes is located in the glass at the periphery of the central hole which has a higher thermal constant than air ({gamma}{sub SiO{sub 2}} = 1.19 x 10{sup -6} 1/K, {gamma}{sub air} = -9 x 10{sup -7} 1/K with {gamma} = dn/dT). To fully control laser driven acceleration, we need to evaluate the thermal and structural consequences of such modes on the PCFs. We are conducting series of interferometric tests to quantify the dependencies of the HC-633-02 (NKT Photonics) propagation constant (k{sub z}) on temperature, vibration amplitude, stress and electric field strength. In this paper we will present the theoretical principles characterizing the thermal behavior of a PCF, the measurements realized for the fundamental telecom mode (TE{sub 00}), and the experimental demonstration of TM-like mode propagation in the HC-633-02 fiber.

Laouar, Rachik

2011-07-06T23:59:59.000Z

Note: This page contains sample records for the topic "measuring thermal evolution" 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

The role of impact and radiogenic heating in the early thermal evolution of Mars  

E-Print Network [OSTI]

The planetary differentiation models of Mars are proposed that take into account core-mantle and core-mantle-crust differentiation. The numerical simulations are presented for the early thermal evolution of Mars spanning up to the initial 25 million years (Ma) of the early solar system, probably for the first time, by taking into account the radiogenic heating due to the short-lived nuclides, 26Al and 60Fe. The influence of impact heating during the accretion of Mars is also incorporated in the simulations. The early accretion of Mars would necessitate a substantial role played by the short-lived nuclides in its heating. 26Al along with impact heating could have provided sufficient thermal energy to the entire body to substantially melt and trigger planetary scale differentiation. This is contrary to the thermal models based exclusively on the impact heating that could not produce widespread melting and planetary differentiation. The early onset of the accretion of Mars perhaps within the initial ~1.5 Ma in t...

Sahijpal, S

2014-01-01T23:59:59.000Z

42

Lifetime Assessment for Thermal Barrier Coatings: Tests for Measuring Mixed Mode Delamination Toughness  

E-Print Network [OSTI]

the thermally grown oxide (TGO), and a porous ceramic topcoat which serves as the thermal insulation. DetailsLifetime Assessment for Thermal Barrier Coatings: Tests for Measuring Mixed Mode Delamination Mechanisms leading to degradation of the adherence of thermal barrier coatings (TBC) used in aircraft

Hutchinson, John W.

43

Ultra-sensitive and Wide Bandwidth Thermal Measurements of Graphene at Low Temperatures  

E-Print Network [OSTI]

exhibits one of the highest thermal conductivities of all measured materials[3, 4]. However at lowUltra-sensitive and Wide Bandwidth Thermal Measurements of Graphene at Low Temperatures K.C. Fong. This paper is organized as follows. We first present the thermal model of the electron gas of graphene at low

44

Measuring the Influence of Grain-Boundary Misorientation on Thermal Groove Geometry in Ceramic Polycrystals  

E-Print Network [OSTI]

Measuring the Influence of Grain-Boundary Misorientation on Thermal Groove Geometry in Ceramic. The width and depth of the thermal grooves formed by these same grain bound- aries were also measured of the grain-boundary misorientation and thermal groove ge- ometry leads to the observation that grain

Rohrer, Gregory S.

45

Solar wind electron temperature and density measurements on the Solar Orbiter with thermal noise spectroscopy  

E-Print Network [OSTI]

Solar wind electron temperature and density measurements on the Solar Orbiter with thermal noise of the plasma thermal noise analysis for the Solar Orbiter, in order to get accurate measurements of the total of their small mass and therefore large thermal speed, the solar wind electrons are expected to play a major role

California at Berkeley, University of

46

Structure Evolution of Graphene Oxide during Thermally Driven Phase Transformation: Is the Oxygen Content Really Preserved?  

E-Print Network [OSTI]

A mild annealing procedure was recently proposed for the scalable enhancement of graphene oxide (GO) properties with the oxygen content preserved, which was demonstrated to be attributed to the thermally driven phase separation. In this work, the structure evolution of GO with mild annealing is closely investigated. It reveals that in addition to phase separation, the transformation of oxygen functionalities also occurs, which leads to the slight reduction of GO membranes and further the enhancement of GO properties. These results are further supported by the density functional theory based calculations. The results also show that the amount of chemically bonded oxygen atoms on graphene decreases gradually and we propose that the strongly physisorbed oxygen species constrained in the holes and vacancies on GO lattice might be responsible for the preserved oxygen content during the mild annealing procedure. The present experimental results and calculations indicate that both the diffusion and transformation of...

Sun, Pengzhan; Liu, He; Wang, Kunlin; Wu, Dehai; Xu, Zhiping; Zhu, Hongwei

2014-01-01T23:59:59.000Z

47

Model Studies of Pore Stability and Evolution in Thermal Barrier Coatings (TBCs)  

E-Print Network [OSTI]

N. Katz, Advanced Ceramics: Thermal Barrier Coatings BeatConductivity of Advanced Ceramic Thermal Barrier CoatingsFatigue Testing of Ceramic Thermal Barrier Coatings, NASA/

Glaeser, A M

2008-01-01T23:59:59.000Z

48

Thermal evolution of boron irradiation induced defects in predoped Si revealed by positron annihilation experiments  

SciTech Connect (OSTI)

The isochronal annealing behavior of high energy (25-72 MeV) boron ion irradiation induced defects in boron-doped silicon is monitored through measurements of positron lifetimes and three distinct defect-evolution stages are identified. The initial boron doping created a defect environment where positrons could sensitively annihilate with the boron electrons, suggesting boron-decorated Si monovacancies as potential trapping sites. The irradiation results in the dissolution of boron from these sites and positrons are then trapped by the empty divacancies of Si. Charge neutralization of divacancies through interaction with boron atoms leads to enhanced positron trapping in the initial stages of isochronal annealing. The divacancies start annealing above 673 K. However, a remarkable defect evolution stage due to the diffusion of the boron atoms beyond their initial depths of penetration is seen above 873 K and it leaves the sample with defects still present even at the highest annealing temperature 1273 K used in this work.

Nambissan, P. M. G.; Bhagwat, P. V.; Kurup, M. B. [Nuclear and Atomic Physics Division, Saha Institute of Nuclear Physics, 1/AF Bidhannagar, Kolkata 700064 (India); Nuclear Physics Division, Bhabha Atomic Research Centre, Trombay, Mumbai 400085 (India); Tata Institute of Fundamental Research, Homi Bhabha Road, Colaba, Mumbai 400005 (India)

2007-06-01T23:59:59.000Z

49

Pump-probe measurements of the thermal conductivity tensor for materials lacking in-plane symmetry  

E-Print Network [OSTI]

1 Pump-probe measurements of the thermal conductivity tensor for materials lacking in conductivity corresponding to the scanning direction. Also, we demonstrate Nb- V as a low thermal conductivity thermal conductivity tensor and the illuminating spots have arbitrary intensity profiles

Cahill, David G.

50

ENS'07 Paris, France, 3-4 December 2007 MEASUREMENTS OF THERMAL CONDUCTIVITY OF ALUMINUM NANOPOWDERS  

E-Print Network [OSTI]

ENS'07 Paris, France, 3-4 December 2007 MEASUREMENTS OF THERMAL CONDUCTIVITY OF ALUMINUM spectroscopy (PAS) as a powerful technique to estimate thermal properties of aluminum nanosized powders. Aluminum nanopowders are considered as effective constituents of energetic materials. Thermal conductivity

Paris-Sud XI, Université de

51

Calculation of TMD Evolution for Transverse Single Spin Asymmetry Measurements  

SciTech Connect (OSTI)

In this letter, we show that it is necessary to include the full treatment of QCD evolution of Transverse Momentum Dependent parton densities to explain discrepancies between HERMES data and recent COMPASS data on a proton target for the Sivers transverse single spin asymmetry in Semi-Inclusive Deep Inelastic Scattering (SIDIS). Calculations based on existing fits to TMDs in SIDIS, and including evolution within the Collins-Soper-Sterman with properly defined TMD PDFs are shown to provide a good explanation for the discrepancy. The non-perturbative input needed for the implementation of evolution is taken from earlier analyses of unpolarized Drell-Yan (DY) scattering at high energy. Its success in describing the Sivers function in SIDIS data at much lower energies is strong evidence in support of the unifying aspect of the QCD TMD-factorization formalism.

Mert Aybat, Ted Rogers, Alexey Prokudin

2012-06-01T23:59:59.000Z

52

The evolution of thermal barrier coatings in gas turbine engine applications  

SciTech Connect (OSTI)

Thermal barrier coatings (TBCs) have been used for almost three decades to extend the life of combustors and augmentors and, more recently, stationary turbine components. Plasma-sprayed yttria-stabilized zirconia TBC currently is bill-of-material on many commercial jet engine parts. A more durable electron beam-physical vapor deposited (EB-PVD) ceramic coating recently has been developed for more demanding rotating as well as stationary turbine components. This ceramic EB-PVD is bill-of-material on turbine blades and vanes in current high thrust engine models and is being considered for newer developmental engines as well. To take maximum advantage of potential TBC benefits, the thermal effect of the TBC ceramic layer must become an integral element of the hot section component design system. To do this with acceptable reliability requires a suitable analytical life prediction model calibrated to engine experience. The latest efforts in thermal barrier coatings are directed toward correlating such models to measured engine performance.

Meier, S.M.; Gupta, D.K. (Pratt and Whitney, East Hartford, CT (United States))

1994-01-01T23:59:59.000Z

53

ThermalPhysicsLaboratory,VanderbiltUniversity Thermal Measurement of harsh environments using  

E-Print Network [OSTI]

PhysicsLaboratory,VanderbiltUniversity Problem/Tests Cook-off Live test on MK45 Mod 4 (NSWC) ) 3/11 #12;Thermal

Walker, D. Greg

54

A comparison between conventional hotothermal frequency scan and the lock-in rate window method in measuring thermal diffirsivity  

E-Print Network [OSTI]

that for thick materials with long thermal transport times across the sample where low-frequency measurements to measure thermal conductivity of materials by steady-state heat flow methods and thermal diffusivity for thermal diffusivity measurements of materials, is presented. In this comparison, a completely noncontact

Mandelis, Andreas

55

Results of actinometric measurements at location of LSF with thermal capacity of 1000 kW  

Science Journals Connector (OSTI)

The paper considers the methods of measuring solar radiation and analyzes the long-term data obtained by actinometric measurements of solar radiation at the location of the LSF with a thermal capacity of 1000 kW ...

A. A. Abdurakhmanov; Yu. B. Sobirov; M. S. Paizullakhonov

2012-07-01T23:59:59.000Z

56

Simultaneous measurement of the thermal conductivity and thermal diffusivity of unconsolidated materials by the transient hot wire method  

Science Journals Connector (OSTI)

This paper describes a new design for the transient hot wire method that can obtain the thermal conductivity and thermal diffusivity of unconsolidated materials. In this method the thermal conductivity is determined from the slope of the temperature rise versus time of an electrically heated wire. The temperature rise is detected as the unbalanced voltage of a precision Wheatstone bridge. This voltage is read by a microcomputer via a high?speed analog?to?digital converter. The instrument was designed so that measurements can be taken over a temperature range of 20200?C and a pressure range of atmospheric down to 10 mTorr. Tests using glycerin indicate an accuracy of 1% for the conductivity and 6% for the diffusivity and a precision of 0.4% for the conductivity and 4.5% for the diffusivity. Measurements have also been made on materials such as 50?? glass beads and unconsolidated spent oil shale.

Greg C. Glatzmaier; W. Fred Ramirez

1985-01-01T23:59:59.000Z

57

Modelling the thermal evolution of enzyme-created bubbles in DNA  

Science Journals Connector (OSTI)

...dependence of these oscillating bubbles. To this aim, the underlying...attention is paid to the stability of the oscillating bubbles under the imposed thermal...attention is paid to the stability of the oscillating bubbles under the imposed thermal...

2005-01-01T23:59:59.000Z

58

Thermal Transport Measurement of Silicon-Germanium Nanowires  

E-Print Network [OSTI]

to the enhanced boundary scattering. Among the nanoscale semiconductor materials, Silicon-Germanium(SiGe) alloy nanowire is a promising candidate for thermoelectric materials The thermal conductivities of SiGe core-shell nanowires with core diameters of 96nm, 129...

Gwak, Yunki

2010-10-12T23:59:59.000Z

59

Measurements of thermal properties of insulation materials by using transient plane source technique  

Science Journals Connector (OSTI)

The paper reports on the measuring technique and values of the measured thermal properties of some commonly used insulation materials produced by local manufacturers in Saudi Arabia. Among the thermal properties of insulation materials, the thermal conductivity (k) is regarded to be the most important since it affects directly the resistance to transmission of heat (R-value) that the insulation material must offer. Other thermal properties, like the specific heat capacity (c) and density (?), are also important only under transient conditions. A well-suited and accurate method for measuring the thermal conductivity and diffusivity of materials is the transient plane source (TPS) technique, which is also called the hot disk (HD). This new technique is used in the present study to measure the thermal conductivity of some insulation materials at room temperature as well as at different elevated temperature levels expected to be reached in practice when these insulations are used in air-conditioned buildings in hot climates. Besides, thermal conductivity values of the same type of insulation material are measured for samples with different densities; generally, higher density insulations are used in building roofs than in walls. The results show that the thermal conductivity increases with increasing temperature and decreases with increasing density over the temperature and density ranges considered in the present investigation.

Saleh A. Al-Ajlan

2006-01-01T23:59:59.000Z

60

Bond strength and stress measurements in thermal barrier coatings  

SciTech Connect (OSTI)

Thermal barrier coatings have been used extensively in aircraft gas turbines for more than 15 years to insulate combustors and turbine vanes from the hot gas stream. Plasma sprayed thermal barrier coatings (TBCs) provide metal temperature reductions as much as 300{degrees}F, with improvements in durability of two times or more being achieved. The introduction of TBCs deposited by electron beam physical vapor deposition (EB-PVD) processes in the last five years has provided a major improvement in durability and also enabled TBCs to be applied to turbine blades for improved engine performance. This program evaluates the bond strength of yttria stabilized zirconia coatings with MCrAlY and Pt-Al bond coats utilizing diffraction and fluorescence methods.

Gell, M.; Jordan, E.

1995-12-31T23:59:59.000Z

Note: This page contains sample records for the topic "measuring thermal evolution" 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

On-line ultrasonic velocity measurements for characterisation of microstructural evaluation during thermal aging of ?-quenched zircaloy-2  

Science Journals Connector (OSTI)

Ultrasonic non-destructive evaluation (NDE) technique has been used for characterisation of evolution of microstructure in ?-quenched and thermally aged zircaloy-2 specimens. On-line ultrasonic velocity measurements have been made in ?-quenched state of zircaloy-2 (A specimen) during heating at different heating rates up to 573K (B specimen), 603K (C specimen) and 623K (D specimen) with holding time periods of 5h for specimens B and C, and 2h for specimen D, at the corresponding maximum temperature, by employing a specially designed experimental set-up. The observed change in velocity at room temperature (298K) before and after ageing for specimens B and D is 0.52% and 0.48%, respectively, and this reveals that intermetallic precipitates are formed during the aging treatment. Ultrasonic measurements are correlated with the hardness, density and microstructural changes.

A. Nishara Begum; V. Rajendran; T. Jayakumar; P. Palanichamy; N. Priyadharsini; S. Aravindan; Baldev Raj

2007-01-01T23:59:59.000Z

62

Ultra-sensitive thermal conductance measurement of one-dimensional nanostructures enhanced by differential bridge  

Science Journals Connector (OSTI)

Thermal conductivity of one-dimensional nanostructures such as nanowires nanotubes and polymer chains is of significant interest for understanding nanoscale thermal transport phenomena as well as for practical applications in nanoelectronics energy conversion and thermal management. Various techniques have been developed during the past decade for measuring this fundamental quantity at the individual nanostructure level. However the sensitivity of these techniques is generally limited to 1 10?9 W/K which is inadequate for small diameter nanostructures that potentially possess thermal conductance ranging between 10?11 and 10?10 W/K. In this paper we demonstrate an experimental technique which is capable of measuring thermal conductance of ?10?11 W/K. The improved sensitivity is achieved by using an on-chip Wheatstone bridge circuit that overcomes several instrumentation issues. It provides a more effective method of characterizing the thermal properties of smaller and less conductive one-dimensional nanostructures. The best sensitivity experimentally achieved experienced a noise equivalent temperature below 0.5 mK and a minimum conductancemeasurement of 1 10?11 W/K. Measuring the temperature fluctuation of both the four-point and bridge measurements over a 4 h time period shows a reduction in measured temperature fluctuation from 100 mK to 0.6 mK. Measurement of a 15 nm Genanowire and background conductance signal with no wire present demonstrates the increased sensitivity of the bridge method over the traditional four-point I-V measurement. This ultra-sensitive measurement platform allows for thermal measurements of materials at new size scales and will improve our understanding of thermal transport in nanoscale structures.

Matthew C. Wingert; Zack C. Y. Chen; Shooshin Kwon; Jie Xiang; Renkun Chen

2012-01-01T23:59:59.000Z

63

Measurements of an ARS DE204S Cryocooler's Thermal and Vibration Characteristics  

SciTech Connect (OSTI)

This document describes measurements that characterize an Advanced Research Systems DE204S cryocooler system. The data is relevant to the thermal performance and vibration characteristics of the cold-head. The thermal measurements include heat load mapping of the 1st and 2nd stage, and temperature fluctuation measurement of the 2nd stage heat station. A comparison of fluctuation measurements by four different sensors is also included to support the 2nd stage fluctuation results. Finally, optical measurement of the cyclic 2nd stage heat station deflection is described.

Haid, B

2004-08-24T23:59:59.000Z

64

Effective thermal conductivity measurements relevant to deep borehole nuclear waste disposal  

E-Print Network [OSTI]

The objective of this work was to measure the effective thermal conductivity of a number of materials (particle beds, and fluids) proposed for use in and around canisters for disposal of high level nuclear waste in deep ...

Shaikh, Samina

2007-01-01T23:59:59.000Z

65

Development of a nanostructure thermal property measurement platform compatible with a transmission electron microscope  

E-Print Network [OSTI]

Measurements of the electrical and thermal transport properties of one-dimensional nanostructures (e.g., nanotubes and nanowires) typically are obtained without detailed knowledge of the specimen's atomicscale structure ...

Harris, C. Thomas (Charles Thomas)

2010-01-01T23:59:59.000Z

66

Thermal hypersensitisation and grating evolution in Ge-doped optical fibre  

Science Journals Connector (OSTI)

Low temperature (sub 1000C) thermal hypersensitisation is reported in germanosilicate optical waveguides. Gratings are written using a CW 266nm laser source. In contrast to laser...

Srensen, H; Canning, J; Kristensen, M

2005-01-01T23:59:59.000Z

67

Time dependent evolution of RF-generated non-thermal particle distributions in fusion plasmas  

Science Journals Connector (OSTI)

We describe fully self-consistent time-dependent simulations of radio frequency (RF) generated ion distributions in the ion cyclotron range of frequencies and RF-generated electron distributions in the lower hybrid range of frequencies using combined FokkerPlanck and full wave electromagnetic field solvers. In each regime, the non-thermal particle distributions have been used in synthetic diagnostic codes to compare with diagnostic measurements from experiment, thus providing validation of the simulation capability. The computational intensive simulations require multiple full wave code runs that iterate with a FokkerPlanck code. We will discuss advanced algorithms that have been implemented to accelerate both the massively parallel full wave simulations as well as the iteration with the distribution code. A vector extrapolation method (Sidi A 2008 Comput. Math. Appl. 56) that permits Jacobian-free acceleration of the traditional fixed point iteration technique is used to reduce the number of iterations needed between the distribution and wave codes to converge to self-consistency. The computational burden of the parallel full wave codes has been reduced by using a more efficient two level parallel decomposition that improves the strong scaling of the codes and reduces the communication overhead.

J C Wright; A Bader; L A Berry; P T Bonoli; R W Harvey; E F Jaeger; J-P Lee; A Schmidt; E D'Azevedo; I Faust; C K Phillips; E Valeo

2014-01-01T23:59:59.000Z

68

Efficient finite-time measurements under thermal regimes  

E-Print Network [OSTI]

Contrary to conventional quantum mechanics, which treats measurement as instantaneous, here we explore a model for finite-time measurement. The main two-level system interacts with the measurement apparatus in a Markovian way described by the Lindblad equation, and with an environment, which does not include the measuring apparatus. To analyse the environmental effects on the final density operator, we use the Redfield approach, allowing us to consider a non-Markovian noise. In the present hybrid theory, to trace out the environmental degrees of freedom, we use a previously-developed analytic method based on superoperator algebra and Nakajima-Zwanzig superoperators. Here, we analyse two types of system-environment interaction, phase and amplitude damping, which allows us to conclude that, in general, a finite-time quantum measurement performed during a certain period is more efficient than an instantaneous measurement performed at the end of it, because the rate of change of the populations is attenuated by the system-measurement apparatus interaction.

Carlos Alexandre Brasil; Leonardo Andreta de Castro; Reginaldo de Jesus Napolitano

2014-07-11T23:59:59.000Z

69

G-Plus report to Owens Corning-thermal conductivity Measurements of Fiberglass  

SciTech Connect (OSTI)

Fiberglass made by Owens Corning is being used in noise reduction of automobile exhaust system. Specifically, the glass fibers are packed inside the muffler to achieve the desired acoustic effect. A secondary benefit of the fibers is to serve as a thermal insulation. Because of this insulating property, the glass fibers can serve to reduce the temperature of the muffler shell. This in turn reduces the need for heat shields around mufflers and reduces the amount of exterior temperature accelerated corrosion of the muffler shell, especially in the winter ''salt belts'' where large amounts of salt are placed on highways to minimize the safety impact of snow and ice. In addition, for some applications the use of the fiberglass could allow the use of lighter weight carbon based polymer composite materials in place of steel for muffler shells. However, in order to properly design exhaust systems without heat shields or to take advantage of new materials, the thermal conductivity of the fiberglass material at operating temperatures (for some applications above 750 C) must be known. We selected two types of Owens Corning glass fibers, 17 {micro}m and 24 {micro}m in diameter, for this study. There are some room temperature thermal conductivity data for the fiberglass, but high temperature data are not available. Based on the thermal radiation model, thermal conductivity should increase rapidly at high temperature, providing less thermal insulation. In addition, thermal conductivity depends on packing density of the glass fibers. We will study the effect of packing density on thermal conductivity. Another issue is that the glass fiber conducts heat better along the fiber, while the conduction across the fibers is poor, because thermal conduction from one fiber to another has to go through an interface with thermal resistance. In fiberglass, most fibers are not in good contact with the surrounding fibers, thus, most heat transfer is dependent on the thermal radiation effect. Among the many methods of measuring thermal conductivity, only a few can be used for glass fibers. The traditional heat flow meter is used in testing thermal insulations near room temperature. At higher temperatures this method cannot be used due to material and instrument limitations. Our plan is to use a transient plane source (TPS) method to measure thermal conductivity directly. The advantage of the TPS method is that measurements can be taken at over 700 C, and covers the temperature of the automobile exhausts. The following is a report for the G-Plus project conducted at ORNL to apply the TPS method to characterizing the thermal conductivity of two types of fiberglass and also the effect of packing density.

Wang, H

2003-04-15T23:59:59.000Z

70

The performance check between whole building thermal performance criteria and exterior wall measured clear wall R-value, thermal bridging, thermal mass, and airtightness  

SciTech Connect (OSTI)

At the last IEA Annex 32 meeting it was proposed that the annex develop the links between level 1 (the whole building performance) and level 2 (the envelope system). This paper provides a case study of just that type of connection. An exterior wall mockup is hot box tested and modeled in the laboratory. Measurements of the steady state and dynamic behavior of this mockup are used as the basis to define the thermal bridging, thermal mass benefit and air tightness of the whole wall system. These level two performance characteristics are related to the whole building performance. They can be analyzed by a finite difference modeling of the wall assembly. An equivalent wall theory is used to convert three dimensional heat flow to one dimensional terms that capture thermal mass effects, which in turn are used in a common whole building simulation model. This paper illustrates a performance check between the thermal performance of a Massive ICF (Insulating Concrete Form) wall system mocked up (level 2) and Whole Building Performance criteria (level 1) such as total space heating and cooling loads (thermal comfort).

Kosny, J.; Christian, J.E.; Desjarlais, A.O. [Oak Ridge National Lab., TN (United States). Buildings Technology Center; Kossecka, E. [Polish Academy of Sciences (Poland); Berrenberg, L. [American Polysteel Forms (United States)

1998-06-01T23:59:59.000Z

71

Transient Non-linear Thermal FEM Simulation of Smart Power Switches and Verification by Measurements  

E-Print Network [OSTI]

Thermal FEM (Finite Element Method) simulations can be used to predict the thermal behavior of power semiconductors in application. Most power semiconductors are made of silicon. Silicon thermal material properties are significantly temperature dependent. In this paper, validity of a common non-linear silicon material model is verified by transient non-linear thermal FEM simulations of Smart Power Switches and measurements. For verification, over-temperature protection behavior of Smart Power Switches is employed. This protection turns off the switch at a pre-defined temperature which is used as a temperature reference in the investigation. Power dissipation generated during a thermal overload event of two Smart Power devices is measured and used as an input stimulus to transient thermal FEM simulations. The duration time of the event together with the temperature reference is confronted with simulation results and thus the validity of the silicon model is proved. In addition, the impact of non-linear thermal properties of silicon on the thermal impedance of power semiconductors is shown.

V. Kosel; R. Sleik; M. Glavanovics

2008-01-07T23:59:59.000Z

72

The thermal conductivity of rock under hydrothermal conditions: measurements and applications  

SciTech Connect (OSTI)

The thermal conductivities of most major rock-forming minerals vary with both temperature and confining pressure, leading to substantial changes in the thermal properties of some rocks at the high temperatures characteristic of geothermal systems. In areas with large geothermal gradients, the successful use of near-surface heat flow measurements to predict temperatures at depth depends upon accurate corrections for varying thermal conductivity. Previous measurements of the thermal conductivity of dry rock samples as a function of temperature were inadequate for porous rocks and susceptible to thermal cracking effects in nonporous rocks. We have developed an instrument for measuring the thermal conductivity of water-saturated rocks at temperatures from 20 to 350 C and confining pressures up to 100 MPa. A transient line-source of heat is applied through a needle probe centered within the rock sample, which in turn is enclosed within a heated pressure vessel with independent controls on pore and confining pressure. Application of this technique to samples of Franciscan graywacke from The Geysers reveals a significant change in thermal conductivity with temperature. At reservoir-equivalent temperatures of 250 C, the conductivity of the graywacke decreases by approximately 25% relative to the room temperature value. Where heat flow is constant with depth within the caprock overlying the reservoir, this reduction in conductivity with temperature leads to a corresponding increase in the geothermal gradient. Consequently, reservoir temperature are encountered at depths significantly shallower than those predicted by assuming a constant temperature gradient with depth. We have derived general equations for estimating the thermal conductivity of most metamorphic and igneous rocks and some sedimentary rocks at elevated temperature from knowledge of the room temperature thermal conductivity. Application of these equations to geothermal exploration should improve estimates of subsurface temperatures derived from heat flow measurements.

Williams, Colin F.; Sass, John H.

1996-01-24T23:59:59.000Z

73

Solar Thermal Energy Use in EU-27 Countries: Evolution and Promotion  

Science Journals Connector (OSTI)

Growth in the use of renewable energies in the 27 European Union (EU-27 ... past decade has been remarkable. Among these energies is solar thermal energy (STE). The average annual growth rate ... has reached almo...

Mara P. del Pablo-Romero; Antonio Snchez-Braza; Enrique Lerma

2013-01-01T23:59:59.000Z

74

A Measurement Method of Actual Thermal Performance of Detached Houses  

E-Print Network [OSTI]

of residential houses based on field measurement (In Japanese), AIJ Report on Environmental engineering Vol.3, 1981 2) Martin Sandberg, J?rgen Eriksson: Commissioning of residential buildings in Sweden, IEA ECBCS Annex40 meetings held in Quebec, 2001/9, Doc...

Iwamae, A.; Nagai, H.; Miura, H.

2004-01-01T23:59:59.000Z

75

Measurement on the thermal neutron capture cross section of w-180  

E-Print Network [OSTI]

We have measured the thermal neutron capture cross section for w-180 nucleus. There is only one previous data on this cross section with a value of 30 $^{+300%}_{-100%}$ barn. To consider w-181 as a low energy neutrino source, the thermal neutron capture cross section should be measured more precisely to estimate the production rate of w-181 inside a nuclear reactor. We measured the cross section of w-180 with a natural tungsten foil and obtained a new value of 21.9 $\\pm$ 2.5 barn

W. G. Kang; Y. D. Kim; J. I. Lee; I. S. Hahn; A. R. Kim; H. J. Kim

2007-04-24T23:59:59.000Z

76

A robust and well shielded thermal conductivity device for low temperature measurements  

SciTech Connect (OSTI)

We present a compact mechanically robust thermal conductivity measurement apparatus for measurements at low temperatures (<1 K) and high magnetic fields on small high-purity single crystal samples. A high-conductivity copper box is used to enclose the sample and all the components. The box provides protection for the thermometers, heater, and most importantly the sample increasing the portability of the mount. In addition to physical protection, the copper box is also effective at shielding radio frequency electromagnetic interference and thermal radiation, which is essential for low temperature measurements. A printed circuit board in conjunction with a braided ribbon cable is used to organize the delicate wiring and provide mechanical robustness.

Toews, W. H.; Hill, R. W. [GWPI and Department of Physics and Astronomy, University of Waterloo, Waterloo, Ontario N2L 3G1 (Canada)] [GWPI and Department of Physics and Astronomy, University of Waterloo, Waterloo, Ontario N2L 3G1 (Canada)

2014-04-15T23:59:59.000Z

77

An apparatus for the measurement of thermal conductivity of liquid neon  

E-Print Network [OSTI]

) ~ 4 Lochtermann, Cryog nics Q, 45 (1963) ~ conductivity of liquid neon. The thermal conductivity measurements will be made using the "hot plate" method used by Grenier for measurements in liquid helium. The test cell to be used is shown 1n figure... for the experiment shown in figure 1 follows the basic design used by Grenier f' or measure- 5 ments of' the thermal conductivity of liquid. helium. The hot plate, Pl, is supported within the guard ring, P , by means of a stainless steel tube. The guard ring...

Jensen, Jerald Norman

2012-06-07T23:59:59.000Z

78

Vision-based Cutaneous Sensor to Measure Both Tactile and Thermal Information for Telexistence  

E-Print Network [OSTI]

-shaped GelForce and a thermo-sensitive paint. The finger- shaped GelForce enables us to measure tactile inside the sensor body. The thermo- sensitive paint is employed to measure thermal information System]: User Interfaces-- Haptic I/O; I.2.9 [Computing Methodologies]: Robotics--Sensors 1 INTRODUCTION

Tachi, Susumu

79

Pressure Wave Measurements from Thermal Cook-Off of an HMX Based High Explosive PBX 9501  

SciTech Connect (OSTI)

A better understanding of thermal cook-off is important for safe handling and storing explosive devices. A number of safety issues exist about what occurs when a cased explosive thermally cooks off. For example, violence of the events as a function of confinement are important for predictions of collateral damage. This paper demonstrates how adjacent materials can be gauged to measure the resulting pressure wave and how this wave propagates in this adjacent material. The output pulse from the thermal cook-off explosive containing fixture is of obvious interest for assessing many scenarios.

Garcia, F; Forbes, J W; Tarver, C M; Urtiew, P A; Greenwood, D W; Vandersall, K S

2001-05-31T23:59:59.000Z

80

Pressure wave measurements from thermal cook-off of an HMX based high explosive  

SciTech Connect (OSTI)

A better understanding of thermal cook-off is important for safe handling and storing explosive devices. A number of safety issues exist about what occurs when a cased explosive thermally cooks off. For example, violence of the events as a function of confinement are important for predictions of collateral damage. This paper demonstrates how adjacent materials can be gauged to measure the resulting pressure wave and how this wave propagates in this adjacent material. The output pulse from the thermal cook-off explosive containing fixture is of obvious interest for assessing many scenarios.

Forbes, J W; Tarver, C M; Urtiew, P A; Garcia, F; Greenwood, D W; Vandersall, K S

2000-10-10T23:59:59.000Z

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


81

Pressure Wave Measurements from Thermal Cook-off of an HMX Based Explosive  

SciTech Connect (OSTI)

A better understanding of thermal cook-off is important for safe handling and storing explosive devices. A number of safety issues exist about what occurs when a cased explosive thermally cooks off. For example, violence of the events as a function of confinement are important for predictions of collateral damage. This paper demonstrates how adjacent materials can be gauged to measure the resulting pressure wave and how this wave propagates in this adjacent material. The output pulse from the thermal cook-off explosive containing fixture is of obvious interest for assessing many scenarios.

Forbes, J W; Tarver, C M; Urtiew, P A; Garcia, F; Greenwood, D W; Vandersall, K S

2001-05-09T23:59:59.000Z

82

Proposed experiment to measure {gamma}-rays from the thermal neutron capture of gadolinium  

SciTech Connect (OSTI)

Gadolinium-157 ({sup 157}Gd) has the largest thermal neutron capture cross section among any stable nuclei. The thermal neutron capture yields {gamma}-ray cascade with total energy of about 8 MeV. Because of these characteristics, Gd is applied for the recent neutrino detectors. Here, we propose an experiment to measure the multiplicity and the angular correlation of {gamma}-rays from the Gd neutron capture. With these information, we expect the improved identification of the Gd neutron capture.

Yano, Takatomi; Ou, I.; Izumi, T.; Yamaguchi, R.; Mori, T.; Sakuda, M. [Department of Physics, Okayama University, Okayama, 700-8530 (Japan)

2012-11-12T23:59:59.000Z

83

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

SciTech Connect (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] [ORNL; Sluder, Scott [ORNL] [ORNL; Storey, John Morse [ORNL] [ORNL

2009-01-01T23:59:59.000Z

84

Analysis of the Temporal Evolution of Thermal Conductivity in Alumina-Water Nanofluid  

E-Print Network [OSTI]

be modeled as particles possessing interfacial shells [8] or nanolayers composed of interfacial particles [9] in an effort to explain observed enhancements of fluid thermal conductivity. Fractal models have also been proposed to describe the effect... of nanoparticle-fluid mixture, Int. J. of Heat and Mass Trans. 48 (2005) 2926-2932. [10] B.X. Wang, L.P. Zing, X.F. Peng, A fractal model for predicting the effective thermal conductivity of liquid with suspension of nanoparticles, Int. J. of Heat and Mass...

Fortenberry, Stephen

2009-09-30T23:59:59.000Z

85

In situ measurements of stress evolution in silicon thin films during  

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

In situ measurements of stress evolution in silicon thin films during In situ measurements of stress evolution in silicon thin films during electrochemical lithiation and delithiation Title In situ measurements of stress evolution in silicon thin films during electrochemical lithiation and delithiation Publication Type Journal Article Year of Publication 2010 Authors Sethuraman, Vijay A., Michael J. Chon, Maxwell Shimshak, Venkat Srinivasan, and Pradeep R. Guduru Journal Journal of Power Sources Volume 195 Start Page 5062 Issue 15 Pagination 5062-5066 Date Published 08/2010 Keywords In situ stress measurement, Lithium-ion battery, Mechanical dissipation, Multi-beam optical sensor (MOS), Open-circuit relaxation, Silicon anode Abstract We report in situ measurements of stress evolution in a silicon thin-film electrode during electrochemical lithiation and delithiation by using the multi-beam optical sensor (MOS) technique. Upon lithiation, due to substrate constraint, the silicon electrode initially undergoes elastic deformation, resulting in rapid rise of compressive stress. The electrode begins to deform plastically at a compressive stress of ca. -1.75 GPa; subsequent lithiation results in continued plastic strain, dissipating mechanical energy. Upon delithiation, the electrode first undergoes elastic straining in the opposite direction, leading to a tensile stress of ca. 1 GPa; subsequently, it deforms plastically during the rest of delithiation. The plastic flow stress evolves continuously with lithium concentration. Thus, mechanical energy is dissipated in plastic deformation during both lithiation and delithiation, and it can be calculated from the stress measurements; we show that it is comparable to the polarization loss. Upon current interruption, both the film stress and the electrode potential relax with similar time constants, suggesting that stress contributes significantly to the chemical potential of lithiated silicon.

86

Determination of thermal accommodation coefficients from heat transfer measurements between parallel plates.  

SciTech Connect (OSTI)

Thermal accommodation coefficients have been derived for a variety of gas-surface combinations using an experimental apparatus developed to measure the pressure dependence of the conductive heat flux between parallel plates at unequal temperature separated by a gas-filled gap. The heat flux is inferred from temperature-difference measurements across the plates in a configuration where the plate temperatures are set with two carefully controlled thermal baths. Temperature-controlled shrouds provide for environmental isolation of the opposing test plates. Since the measured temperature differences in these experiments are very small (typically 0.3 C or less over the entire pressure range), high-precision thermistors are used to acquire the requisite temperature data. High-precision components have also been utilized on the other control and measurement subsystems in this apparatus, including system pressure, gas flow rate, plate alignment, and plate positions. The apparatus also includes the capability for in situ plasma cleaning of the installed test plates. Measured heat-flux results are used in a formula based on Direct Simulation Monte Carlo (DSMC) code calculations to determine the thermal accommodation coefficients. Thermal accommodation coefficients have been determined for three different gases (argon, nitrogen, helium) in contact with various surfaces. Materials include metals and alloys such as aluminum, gold, platinum, and 304 stainless steel. A number of materials important to fabrication of Micro Electro Mechanical Systems (MEMS) devices have also been examined. For most surfaces, coefficient values are near 0.95, 0.85, and 0.45 for argon, nitrogen, and helium, respectively. Only slight differences in accommodation as a function of surface roughness have been seen. Surface contamination appears to have a more significant effect: argon plasma treatment has been observed to reduce thermal accommodation by as much as 0.10 for helium. Mixtures of argon and helium have also been examined, and the results have been compared to DSMC simulations incorporating thermal-accommodation values from single-species experiments.

Gallis, Michail A.; Castaneda, Jaime N.; Rader, Daniel John; Torczynski, John Robert; Trott, Wayne Merle

2010-10-01T23:59:59.000Z

87

Pump-probe measurements of the thermal conductivity tensor for materials lacking in-plane symmetry  

SciTech Connect (OSTI)

We previously demonstrated an extension of time-domain thermoreflectance (TDTR) which utilizes offset pump and probe laser locations to measure in-plane thermal transport properties of multilayers. However, the technique was limited to systems of transversely isotropic materials studied using axisymmetric laser intensities. Here, we extend the mathematics so that data reduction can be performed on non-transversely isotropic systems. An analytic solution of the diffusion equation for an N-layer system is given, where each layer has a homogenous but otherwise arbitrary thermal conductivity tensor and the illuminating spots have arbitrary intensity profiles. As a demonstration, we use both TDTR and time-resolved magneto-optic Kerr effect measurements to obtain thermal conductivity tensor elements of <110> ?-SiO{sub 2}. We show that the out-of-phase beam offset sweep has full-width half-maxima that contains nearly independent sensitivity to the in-plane thermal conductivity corresponding to the scanning direction. Also, we demonstrate a Nb-V alloy as a low thermal conductivity TDTR transducer layer that helps improve the accuracy of in-plane measurements.

Feser, Joseph P. [Department of Mechanical Engineering, University of Delaware, Newark, Delaware 19716 (United States); Liu, Jun; Cahill, David G. [Department of Materials Science and Engineering, and Frederick-Seitz Materials Research Laboratory, University of Illinois, Urbana, Illinois 61801 (United States)

2014-10-15T23:59:59.000Z

88

MEMS test structure for measuring thermal conductivity of thin films L. La Spina, N. Nenadovi*, A. W. van Herwaarden**,  

E-Print Network [OSTI]

from handbook values for the corresponding bulk materials. This is because the thermal transport the one is patterned with the film-to- analyze (FTA). In this case, the thermal resistance can be regarded as a parallel between the thermal resistances of the supporting membrane and of the FTA. Thus, the measured

Technische Universiteit Delft

89

Fusion product measurements of the local ion thermal diffusivity in the PLT tokamak  

SciTech Connect (OSTI)

Measurement of the gradient of the d-d fusion rate profile in an ohmic PLT plasma is used to deduce the gradient of the ion temperature and, thus, the local ion thermal diffusivity through an energy balance analysis. The inferred ion diffusivity is consistent with neoclassical theory.

Heidbrink, W.W.; Lovberg, J.; Strachan, J.D.; Bell, R.E.

1986-03-01T23:59:59.000Z

90

Solar wind electron density and temperature over solar cycle 23: Thermal noise measurements on Wind  

E-Print Network [OSTI]

Solar wind electron density and temperature over solar cycle 23: Thermal noise measurements on Wind; received in revised form 6 April 2005; accepted 25 April 2005 Abstract We present the solar wind plasma parameters obtained from the Wind spacecraft during more than nine years, encompassing almost the whole solar

California at Berkeley, University of

91

The tectonic evolution of the Southern Alps, New Zealand: insights from fully thermally coupled dynamical modelling  

Science Journals Connector (OSTI)

......The possible contribution of frictional heating to the geothermal regime of the Southern...is well established from measurements in oil exploration drillholes, only two measurements...Nappe Tectonics, eds McClay, K.R. Price, N.J., Spec. Publ. Geol. Soc......

Geoffrey E. Batt; Jean Braun

1999-02-01T23:59:59.000Z

92

Measurement of concrete E-modulus evolution since casting: A novel method based on ambient vibration  

SciTech Connect (OSTI)

The use of ambient vibration tests to characterize the evolution of E-modulus of concrete right after casting is investigated in this paper. A new methodology is proposed, which starts by casting a concrete cylindrical beam inside a hollow acrylic formwork. This beam is then placed horizontally, simply supported at both extremities, and vertical accelerations resulting from ambient vibration are measured at mid-span. Processing these mid-span acceleration time series using power spectral density functions allows a continuous identification of the first flexural frequency of vibration of the composite beam, which in turn is correlated with the evolutive E-modulus of concrete since casting. Together with experiments conducted with the proposed methodology, a complementary validation campaign for concrete E-modulus determination was undertaken by static loading tests performed on the composite beam, as well as by standard compressive tests of concrete cylinders of the same batch loaded at different ages.

Azenha, Miguel, E-mail: miguel.azenha@civil.uminho.p [LABEST - Laboratory for the Concrete Technology and Structural Behaviour, Faculdade de Engenharia da Universidade do Porto, Rua Dr. Roberto Frias, 4200-465 Porto (Portugal); ISISE - Institute for Sustainability and Innovation in Structural Engineering, Universidade do Minho, Escola de Engenharia, Campus de Azurem, 4800-058 Guimaraes (Portugal); Magalhaes, Filipe [VIBEST - Laboratory of Vibrations and Structural Monitoring, Faculdade de Engenharia da Universidade do Porto, Rua Dr. Roberto Frias, 4200-465 Porto (Portugal); Faria, Rui [LABEST - Laboratory for the Concrete Technology and Structural Behaviour, Faculdade de Engenharia da Universidade do Porto, Rua Dr. Roberto Frias, 4200-465 Porto (Portugal); Cunha, Alvaro [VIBEST - Laboratory of Vibrations and Structural Monitoring, Faculdade de Engenharia da Universidade do Porto, Rua Dr. Roberto Frias, 4200-465 Porto (Portugal)

2010-07-15T23:59:59.000Z

93

Thermal-Equilibrium Properties of Vacancies in Metals through Current-Noise Measurements  

Science Journals Connector (OSTI)

We report a new method of measuring thermal-equilibrium properties of vacancies in metals through current-noise measurements. Aluminum noise spectra taken at 435 and 475C directly yield vacancy lifetimes ?0=4.710-3and2.810-3 sec, respectively, corresponding to a migration energy Em=0.6 eV, and permit estimation of a unit vacancy resistivity ??v=1.910-8 ?m/at.% from the measured product (??v)2?v, ?v being the vacancy concentration taken from literature data.

M. Celasco; F. Fiorillo; P. Mazzetti

1976-01-05T23:59:59.000Z

94

Thermal history sensors for non-destructive temperature measurements in harsh environments  

Science Journals Connector (OSTI)

The operating temperature is a critical physical parameter in many engineering applications however can be very challenging to measure in certain environments particularly when access is limited or on rotating components. A new quantitative non-destructive temperature measurement technique has been proposed which relies on thermally induced permanent changes in ceramic phosphors. This technique has several distinct advantages over current methods for many different applications. The robust ceramic material stores the temperature information allowing long term thermal exposures in harsh environment to be measured at a convenient time. Additionally rare earth dopants make the ceramic phosphorescent so that the temperature information can be interpreted by automated interrogation of the phosphorescent light. This technique has been demonstrated by application of YAG doped with dysprosium and europium as coatings through the air-plasma spray process. Either material can be used to measure temperature over a wide range namely between 300C and 900C. Furthermore results show that the material records the peak exposure temperature and prolonged exposure at lower temperatures would have no effect on the temperature measurement. This indicates that these materials could be used to measure peak operating temperatures in long-term testing.

2014-01-01T23:59:59.000Z

95

Thermal history sensors for non-destructive temperature measurements in harsh environments  

SciTech Connect (OSTI)

The operating temperature is a critical physical parameter in many engineering applications, however, can be very challenging to measure in certain environments, particularly when access is limited or on rotating components. A new quantitative non-destructive temperature measurement technique has been proposed which relies on thermally induced permanent changes in ceramic phosphors. This technique has several distinct advantages over current methods for many different applications. The robust ceramic material stores the temperature information allowing long term thermal exposures in harsh environment to be measured at a convenient time. Additionally, rare earth dopants make the ceramic phosphorescent so that the temperature information can be interpreted by automated interrogation of the phosphorescent light. This technique has been demonstrated by application of YAG doped with dysprosium and europium as coatings through the air-plasma spray process. Either material can be used to measure temperature over a wide range, namely between 300C and 900C. Furthermore, results show that the material records the peak exposure temperature and prolonged exposure at lower temperatures would have no effect on the temperature measurement. This indicates that these materials could be used to measure peak operating temperatures in long-term testing.

Pilgrim, C. C. [Mechanical Engineering, Imperial College London, London, SW7 2AZ, UK and Sensor Coating Systems, Imperial Incubator, Bessemer Building, Level 1 and 2, Imperial College London, London SW7 2AZ (United Kingdom); Heyes, A. L. [Energy Technology and Innovation Initiative, University of Leeds, Leeds, LS2 9JT (United Kingdom); Feist, J. P. [Sensor Coating Systems, Imperial Incubator, Bessemer Building, Level 1 and 2, Imperial College London, London SW7 2AZ (United Kingdom)

2014-02-18T23:59:59.000Z

96

The measurement of absolute thermal neutron flux using liquid scintillation counting techniques  

E-Print Network [OSTI]

was computed as the square root of the sum of the squares of the individual errors . The flux at the same location in the core and at the same reactor power level was measured by the conventional technique of gold foil 34 activation. This measurement... back to 1932 when the neutron was discovered by Chadwick. With the advent of the nuclear reactor in 1942 the problem of absolute neutron flux determination became increasingly important. Since the operating power of a thermal reactor is directly...

Walker, Jack Vernon

2012-06-07T23:59:59.000Z

97

Measurement of neutron capture on $^{48}$Ca at thermal and thermonuclear energies  

E-Print Network [OSTI]

At the Karlsruhe pulsed 3.75\\,MV Van de Graaff accelerator the thermonuclear $^{48}$Ca(n,$\\gamma$)$^{49}$Ca(8.72\\,min) cross section was measured by the fast cyclic activation technique via the 3084.5\\,keV $\\gamma$-ray line of the $^{49}$Ca-decay. Samples of CaCO$_3$ enriched in $^{48}$Ca by 77.87\\,\\% were irradiated between two gold foils which served as capture standards. The capture cross-section was measured at the neutron energies 25, 151, 176, and 218\\,keV, respectively. Additionally, the thermal capture cross-section was measured at the reactor BR1 in Mol, Belgium, via the prompt and decay $\\gamma$-ray lines using the same target material. The $^{48}$Ca(n,$\\gamma$)$^{49}$Ca cross-section in the thermonuclear and thermal energy range has been calculated using the direct-capture model combined with folding potentials. The potential strengths are adjusted to the scattering length and the binding energies of the final states in $^{49}$Ca. The small coherent elastic cross section of $^{48}$Ca+n is explained through the nuclear Ramsauer effect. Spectroscopic factors of $^{49}$Ca have been extracted from the thermal capture cross-section with better accuracy than from a recent (d,p) experiment. Within the uncertainties both results are in agreement. The non-resonant thermal and thermonuclear experimental data for this reaction can be reproduced using the direct-capture model. A possible interference with a resonant contribution is discussed. The neutron spectroscopic factors of $^{49}$Ca determined from shell-model calculations are compared with the values extracted from the experimental cross sections for $^{48}$Ca(d,p)$^{49}$Ca and $^{48}$Ca(n,$\\gamma$)$^{49}$Ca.

H. Beer; C. Coceva; P. V. Sedyshev; Yu. P. Popov; H. Herndl; R. Hofinger; P. Mohr; H. Oberhummer

1996-08-07T23:59:59.000Z

98

New contactless method for thermal diffusivity measurements using modulated photothermal radiometry  

SciTech Connect (OSTI)

Modulated photothermal radiometry is a non-destructive and contactless technique for the characterization of materials. It has two major advantages: a good signal-to-noise ratio through a synchronous detection and a low dependence on the heating power and the optical properties of the sample surface. This paper presents a new method for characterizing the thermal diffusivity of a material when the phase shift between a modulated laser power signal and the thermal signal of a plate sample is known at different frequencies. The method is based on a three-dimensional analytical model which is used to determine the temperature amplitude and the phase in the laser heating of the plate. A new simple formula was developed through multi-parametric analysis to determine the thermal diffusivity of the plate with knowledge of the frequency at the minimum phase shift, the laser beam radius r{sub 0} and the sample thickness L. This method was developed to control the variation of the thermal diffusivity of nuclear components and it was first applied to determine the thermal diffusivity of different metals: 304 L stainless steel, nickel, titanium, tungsten, molybdenum, zinc, and iron. The experimental results were obtained with 5%10% accuracy and corresponded well with the reference values. The present paper also demonstrates the limit of application of this method for plate with thickness r{sub 0}/100 ? L ? r{sub 0}/2. The technique is deemed interesting for the characterization of barely accessible components that require a contactless measurement.

Pham Tu Quoc, S., E-mail: sang.phamtuquoc@cea.fr; Cheymol, G.; Semerok, A. [French Alternative Energies and Atomic Energy Commission, Division of Nuclear Energy, DEN/DANS/DPC/SEARS/LISL, 91191 Gif/Yvette (France)] [French Alternative Energies and Atomic Energy Commission, Division of Nuclear Energy, DEN/DANS/DPC/SEARS/LISL, 91191 Gif/Yvette (France)

2014-05-15T23:59:59.000Z

99

A review of recent measurements of optical and thermal properties of. alpha. -mercuric iodide  

SciTech Connect (OSTI)

The knowledge of the physical properties of a crystal and their relation to the nature and content of defects are essential for both applications and fundamental reasons. Alpha-mercuric iodide ({alpha}-HgI{sub 2}) is a material which was found important applications as room temperature X-ray and gamma ray detectors. Some recent thermal and optical measurements of this material, using the samples of improved crystallinity which are now available, are reviewed below. Heretofore, these properties have received less attention than the mechanical and electrical properties, particularly at elevated temperatures. In the technology of {alpha}-HgI{sub 2} where there is a continuing motivation to obtain larger single crystals without compromising the material quality, a better knowledge of the thermal and optical properties may lead to improvements in the processes of material purification, crystal growth and device fabrication.

Burger, A.; Morgan, S.H.; Silberman, E. (Fisk Univ., Nashville, TN (United States). Dept. of Physics); Nason, D.; Cheng, A.Y. (EG and G Energy Measurements, Inc., Goleta, CA (United States). Santa Barbara Operations)

1991-01-01T23:59:59.000Z

100

Gamma-gamma directional correlation measurements in 84Kr following thermal neutron capture by natural krypton  

Science Journals Connector (OSTI)

Directional correlations of gamma-ray cascades in 84Kr have been measured following thermal neutron capture by a pressurised natural krypton gas target. Gamma-ray singles spectra were measured up to 5.5 MeV and the correlation data were obtained for the energy range 0.2-2.5 MeV. A decay scheme was developed on the basis of coincidence measurements. The data allow spin-parity assignments to be made to most levels lying below 3.5 MeV and multipole mixing ratios to be evaluated for the more intense transitions. The results are fitted to the SU(5) limit of the IBM-1 and to the IBM-2 and are also compared with the predictions of the dynamic deformation model which indicates that 84Kr is the only krypton isotope with a prolate equilibrium shape. A possible mixed symmetry 2+ state at 2.623 MeV is identified.

S A Hamada; W D Hamilton; F Hoyler

1987-01-01T23:59:59.000Z

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


101

A thermal method for measuring the rate of water movement in plants  

E-Print Network [OSTI]

L?BP A 8 V a L ?BPA8B8 op A THERMAL METHOD FOR MEASURING THE RATE OF WATER MOVEMENT IN PLANTS A Dissertation By Morris Elkins Bloodworth Vao Submitted to the Graduate School of the Agricultural and Mechanical College of Texas in Partial... Fulfillment of the Requirements for the Degree of DOCTOR OF PHILOSOPHY May, 1958 TLX Major Subject: Soil Physics p ^i???pP ??^i?? ??? ??p?????? ^i? ?p^? ?? WATER MOVEMENT IN PLANTS A Dissertation By Morris Elkins Bloodworth Approved as to style...

Bloodworth, Morris Elkins

1958-01-01T23:59:59.000Z

102

MULTISCALE THERMAL-INFRARED MEASUREMENTS OF THE MAUNA LOA CALDERA, HAWAII  

SciTech Connect (OSTI)

Until recently, most thermal infrared measurements of natural scenes have been made at disparate scales, typically 10{sup {minus}3}-10{sup {minus}2} m (spectra) and 10{sup 2}-10{sup 3} m (satellite images), with occasional airborne images (10{sup 1} m) filling the gap. Temperature and emissivity fields are spatially heterogeneous over a similar range of scales, depending on scene composition. A common problem for the land surface, therefore, has been relating field spectral and temperature measurements to satellite data, yet in many cases this is necessary if satellite data are to be interpreted to yield meaningful information about the land surface. Recently, three new satellites with thermal imaging capability at the 10{sup 1}-10{sup 2} m scale have been launched: MTI, TERRA, and Landsat 7. MTI acquires multispectral images in the mid-infrared (3-5{micro}m) and longwave infrared (8-10{micro}m) with 20m resolution. ASTER and MODIS aboard TERRA acquire multispectral longwave images at 90m and 500-1000m, respectively, and MODIS also acquires multispectral mid-infrared images. Landsat 7 acquires broadband longwave images at 60m. As part of an experiment to validate the temperature and thermal emissivity values calculated from MTI and ASTER images, we have targeted the summit region of Mauna Loa for field characterization and near-simultaneous satellite imaging, both on daytime and nighttime overpasses, and compare the results to previously acquired 10{sup {minus}1} m airborne images, ground-level multispectral FLIR images, and the field spectra. Mauna Loa was chosen in large part because the 4x6km summit caldera, flooded with fresh basalt in 1984, appears to be spectrally homogeneous at scales between 10{sup {minus}1} and 10{sup 2} m, facilitating the comparison of sensed temperature. The validation results suggest that, with careful atmospheric compensation, it is possible to match ground measurements with measurements from space, and to use the Mauna Loa validation site for cross-comparison of thermal infrared sensors and temperature/emissivity extraction algorithms.

L. BALICK; A. GILLESPIE; ET AL

2001-03-01T23:59:59.000Z

103

Apparatus and method for measurement of weak optical absorptions by thermally induced laser pulsing  

DOE Patents [OSTI]

The thermal lensing phenomenon is used as the basis for measurement of weak optical absorptions when a cell containing the sample to be investigated is inserted into a normally continuous-wave operation laser-pumped dye laser cavity for which the output coupler is deliberately tilted relative to intracavity circulating laser light, and pulsed laser output ensues, the pulsewidth of which can be related to the sample absorptivity by a simple algorithm or calibration curve. A minimum detection limit of less than 10[sup [minus]5] cm[sup [minus]1] has been demonstrated using this technique. 6 figs.

Cremers, D.A.; Keller, R.A.

1985-10-01T23:59:59.000Z

104

Measurement of temperature-dependent thermal conductivity and viscosity of TiO{sub 2}-water nanofluids  

SciTech Connect (OSTI)

Nanofluid is an innovative heat transfer fluid with superior potential for enhancing the heat transfer performance of conventional fluids. Many attempts have been made to investigate its thermal conductivity and viscosity, which are important thermophysical properties. No definitive agreements have emerged, however, about these properties. This article reports the thermal conductivity and dynamic viscosity of nanofluids experimentally. TiO{sub 2} nanoparticles dispersed in water with volume concentration of 0.2-2 vol.% are used in the present study. A transient hot-wire apparatus is used for measuring the thermal conductivity of nanofluids whereas the Bohlin rotational rheometer (Malvern Instrument) is used to measure the viscosity of nanofluids. The data are collected for temperatures ranging from 15 C to 35 C. The results show that the measured viscosity and thermal conductivity of nanofluids increased as the particle concentrations increased and are higher than the values of the base liquids. Furthermore, thermal conductivity of nanofluids increased with increasing nanofluid temperatures and, conversely, the viscosity of nanofluids decreased with increasing temperature of nanofluids. Moreover, the measured thermal conductivity and viscosity of nanofluids are quite different from the predicted values from the existing correlations and the data reported by other researchers. Finally, new thermophysical correlations are proposed for predicting the thermal conductivity and viscosity of nanofluids. (author)

Duangthongsuk, Weerapun; Wongwises, Somchai [Fluid Mechanics, Thermal Engineering and Multiphase Flow Research Lab. (FUTURE), Department of Mechanical Engineering, King Mongkut's University of Technology Thonburi, 126 Bangmod, Bangkok 10140 (Thailand)

2009-04-15T23:59:59.000Z

105

MEASUREMENTS OF ANISOTROPIC ION TEMPERATURES, NON-THERMAL VELOCITIES, AND DOPPLER SHIFTS IN A CORONAL HOLE  

SciTech Connect (OSTI)

We present a new diagnostic allowing one to measure the anisotropy of ion temperatures and non-thermal velocities, as well as Doppler shifts with respect to the ambient magnetic field. This method provides new results, as well as an independent test for previous measurements obtained with other techniques. Our spectral data come from observations of a low-latitude, on-disk coronal hole. A potential field source surface model was used to calculate the angle between the magnetic field lines and the line of sight for each spatial bin of the observation. A fit was performed to determine the line widths and Doppler shifts parallel and perpendicular to the magnetic field. For each line width component we derived ion temperatures T {sub i,} and T {sub i, Parallel-To} and non-thermal velocities v {sub nt,} and v {sub nt, Parallel-To }. T {sub i,} was cooler than off-limb polar coronal hole measurements, suggesting increasing collisional cooling with decreasing height. T {sub i, Parallel-To} is consistent with a uniform temperature of (1.8 {+-} 0.2) Multiplication-Sign 10{sup 6} K for each ion. Since parallel ion heating is expected to be weak, this ion temperature should reflect the proton temperature. A comparison between our results and others implies a large proton temperature gradient around 1.02 R {sub Sun }. The non-thermal velocities are thought to be proportional to the amplitudes of various waves. Our results for v {sub nt,} agree with Alfven wave amplitudes inferred from off-limb polar coronal hole line width measurements. Our v {sub nt, Parallel-To} results are consistent with slow magnetosonic wave amplitudes inferred from Fourier analysis of time-varying intensity fluctuations. Doppler shift measurements yield outflows of Almost-Equal-To 5 km s{sup -1} for ions formed over a broad temperature range. This differs from other studies that found a strong Doppler shift dependence on formation temperature.

Hahn, M.; Savin, D. W. [Columbia Astrophysics Laboratory, Columbia University, MC 5247, 550 West 120th Street, New York, NY 10027 (United States)] [Columbia Astrophysics Laboratory, Columbia University, MC 5247, 550 West 120th Street, New York, NY 10027 (United States)

2013-02-15T23:59:59.000Z

106

Strains in Thermally Growing Alumina Films Measured in-situ usingSynchrotron X-rays  

SciTech Connect (OSTI)

Strains in thermally grown oxides have been measured in-situ, as the oxides develop and evolve. Extensive data have been acquired from oxides grown in air at elevated temperatures on different model alloys that form Al{sub 2}O{sub 3}. Using synchrotron x-rays at the Advanced Photon Source (Beamline 12BM, Argonne National Laboratory), Debye-Scherrer diffraction patterns from the oxidizing specimen were recorded every 5 minutes during oxidation and subsequent cooling. The diffraction patterns were analyzed to determine strains in the oxides, as well as phase changes and the degree of texture. To study a specimen's response to stress perturbation, the oxidizing temperature was quickly cooled from 1100 to 950 C to impose a compressive thermal stress in the scale. This paper describes this new experimental approach and gives examples from oxidized {beta}-NiAl, Fe-20Cr-10Al, Fe-28Al-5Cr and H{sub 2}-annealed Fe-28Al-5Cr (all at. %) alloys to illustrate some current understanding of the development and relaxation of growth stresses in Al{sub 2}O{sub 3}.

Hou, P.Y.; Paulikas, A.P.; Veal, B.W.

2006-01-02T23:59:59.000Z

107

Improved 3-omega measurement of thermal conductivity in liquid, gases, and powders using a metal-coated optical fiber  

Science Journals Connector (OSTI)

A novel 3?thermal conductivitymeasurement technique called metal-coated 3? is introduced for use with liquids gases powders and aerogels. This technique employs a micron-scale metal-coated glass fiber as a heater/thermometer that is suspended within the sample. Metal-coated 3? exceeds alternate 3? based fluid sensing techniques in a number of key metrics enabling rapid measurements of small samples of materials with very low thermal effusivity (gases) using smaller temperature oscillations with lower parasitic conduction losses. Its advantages relative to existing fluid measurement techniques including transient hot-wire steady-state methods and solid-wire 3? are discussed. A generalized n-layer concentric cylindrical periodic heating solution that accounts for thermal boundary resistance is presented. Improved sensitivity to boundary conductance is recognized through this model. Metal-coated 3? was successfully validated through a benchmark study of gases and liquids spanning two-orders of magnitude in thermal conductivity.

Scott N. Schiffres; Jonathan A. Malen

2011-01-01T23:59:59.000Z

108

Thermal Shock Resistance (TSR) and Thermal Fatigue Resistance (TFR) of Refractory Materials. Evaluation Method Based on the Dynamic Elastic Modulus  

Science Journals Connector (OSTI)

The importance of the thermal shock resistance (TSR) of refractory material is discussed. Understanding the evolution of thermal ... undergo repeated thermal cycling. The thermal fatigue resistance (TFR) behavior...

Nicols M. Rendtorff; Esteban F. Aglietti

2014-01-01T23:59:59.000Z

109

Resistivity measurements of halide-salt/MgO separators for thermal cells  

SciTech Connect (OSTI)

Resistivities of 20 compositions of halide-salt/MgO mixtures (various selections and percentages of LiF, LiCl, LiBr, KCl, KBr, CsBr, and MgO) to be used in Li-alloy/metal sulfide cells have been measured at temperatures between the melting point of a particular mixture and 500{degrees}C. The resistivities were determined with cold-pressed electrolyte-binder pellets by using a special cell and DC measuring technique. Temperature, salt composition, and MgO content were found to have a strong influence on resistivity. These factors are listed in decreasing order of the magnitude of the effect. The fabrication density (porosity) of the pellet also has some effect on resistivity. These measured resistivities provide a data base to select optimum compositions of electrolyte-binder pellets for LiSi/FeS{sub 2} thermal batteries and to calculate area-specific resistances of these components for battery modeling and optimization. 5 refs., 7 figs.

Redey, L.; McParland, M. (Argonne National Lab., IL (USA)); Guidotti, R. (Sandia National Labs., Albuquerque, NM (USA))

1990-01-01T23:59:59.000Z

110

Measurement of Reactive Hydroxyl Radical Species Inside the Biosolutions During Non-thermal Atmospheric Pressure Plasma Jet Bombardment onto the Solution  

Science Journals Connector (OSTI)

Non-thermal atmospheric pressure plasma jet could generate various kinds of radicals ... The electron temperature and ion density for this non-thermal plasma jet have been measured to be about...13cm?3 in this e...

Yong Hee Kim; Young June Hong; Ku Youn Baik

2014-05-01T23:59:59.000Z

111

Measurement of thermal properties of select intact and weathered granulites and their relationship to rock properties  

Science Journals Connector (OSTI)

...in hard rock: Renewable Energy, 28 , no.-14...basalt samples in Egypt: Journal of Thermal...in hard rock: Renewable Energy, 28, no. 14...basalt samples in Egypt: Journal of Thermal...parameterization on surface energy fluxes and temperatures...

D. Ramakrishnan; Rishikesh Bharti; M. Nithya; K. N. Kusuma; K. D. Singh

112

Filtered Rayleigh scattering diagnostic for multi-parameter thermal-fluids measurements : LDRD final report.  

SciTech Connect (OSTI)

Simulation-based life-cycle-engineering and the ASCI program have resulted in models of unprecedented size and fidelity. The validation of these models requires high-resolution, multi-parameter diagnostics. Within the thermal-fluids disciplines, the need for detailed, high-fidelity measurements exceeds the limits of current engineering sciences capabilities and severely tests the state of the art. The focus of this LDRD is the development and application of filtered Rayleigh scattering (FRS) for high-resolution, nonintrusive measurement of gas-phase velocity and temperature. With FRS, the flow is laser-illuminated and Rayleigh scattering from naturally occurring sources is detected through a molecular filter. The filtered transmission may be interpreted to yield point or planar measurements of three-component velocities and/or thermodynamic state. Different experimental configurations may be employed to obtain compromises between spatial resolution, time resolution, and the quantity of simultaneously measured flow variables. In this report, we present the results of a three-year LDRD-funded effort to develop FRS combustion thermometry and Aerosciences velocity measurement systems. The working principles and details of our FRS opto-electronic system are presented in detail. For combustion thermometry we present 2-D, spatially correlated FRS results from nonsooting premixed and diffusion flames and from a sooting premixed flame. The FRS-measured temperatures are accurate to within {+-}50 K (3%) in a premixed CH4-air flame and within {+-}100 K for a vortex-strained diluted CH4-air diffusion flame where the FRS technique is severely tested by large variation in scattering cross section. In the diffusion flame work, FRS has been combined with Raman imaging of the CH4 fuel molecule to correct for the local light scattering properties of the combustion gases. To our knowledge, this is the first extension of FRS to nonpremixed combustion and the first use of joint FRS-Raman imaging. FRS has been applied to a sooting C2H4-air flame and combined with LII to assess the upper sooting limit where FRS may be utilized. The results from this sooting flame show FRS temperatures has potential for quantitative temperature imaging for soot volume fractions of order 0.1 ppm. FRS velocity measurements have been performed in a Mach 3.7 overexpanded nitrogen jet. The FRS results are in good agreement with expected velocities as predicted by inviscid analysis of the jet flowfield. We have constructed a second FRS opto-electronic system for measurements at Sandia's hypersonic wind tunnel. The details of this second FRS system are provided here. This facility is currently being used for velocity characterization of these production hypersonic facilities.

Beresh, Steven Jay; Grasser, Thomas W.; Kearney, Sean Patrick; Schefer, Robert W.

2004-01-01T23:59:59.000Z

113

EXPERIMENTAL MEASUREMENTS OF THE INTERFACE THERMAL CONDUCTANCE OF A LITHIUM METATITANATE PEBBLE BED  

E-Print Network [OSTI]

, CA 90095 aliabousena@engineering.ucla.edu The thermal properties of the lithium ceramics pebble beds will help to create a reliable database of the thermal properties of the lithium ceramics pebble beds. I heat is transferred from the hot lithium ceramic pebble beds to the coolant. The thermal properties

Abdou, Mohamed

114

Contamination of Cluster Radio Sources in the Measurement of the Thermal Sunyaev-Zel'dovich Angular Power Spectrum  

E-Print Network [OSTI]

We present a quantitative estimate of the confusion of cluster radio halos and galaxies in the measurement of the angular power spectrum of the thermal Sunyaev-Zel'dovich (SZ) effect. To achieve the goal, we use a purely analytic approach to both radio sources and dark matter of clusters by incorporating empirical models and observational facts together with some theoretical considerations. It is shown that the correction of cluster radio halos and galaxies to the measurement of the thermal SZ angular power spectrum is no more than 20% at $l>2000$ for observing frequencies $\

Wei Zhou; Xiang-Ping Wu

2003-09-26T23:59:59.000Z

115

MONITORING POWER PLANT EFFICIENCY USING THE MICROWAVE-EXCITED THERMAL-ACOUSTIC EFFECT TO MEASURE UNBURNED CARBON  

SciTech Connect (OSTI)

The objective of this project is to explore microwave-excited thermal-acoustic (META) phenomena for quantitative analysis of granular and powdered materials, with the culmination of the research to be an on-line carbon-in-ash monitor for coal-fired power plants. This technique of analyzing unburned carbon in fly ash could be a less tedious and time consuming method as compared to the traditional LOI manual procedure. Phase 1 of the research focused on off-line single-frequency thermal-acoustic measurements where an off-line fly ash monitor was constructed that could operate as analytical tool to explore instrument and methodology parameters for quantifying the microwave-excited thermal-acoustic effect of carbon in fly ash, and it was determined that the off-line thermal-acoustic technique could predict the carbon content of a random collection of fly ashes with a linear correlation constant of R{sup 2} = 0.778. Much higher correlations are expected for fly ashes generated from a single boiler. Phase 2 of the research developing a methodology to generate microwave spectra of various powders, including fly ash, coal, and inorganic minerals, and to determine if these microwave spectra could be used for chemical analyses. Although different minerals produced different responses, higher resolution microwave spectra would be required to be able to distinguish among minerals. Phase 3 of the research focused on the development of an on-line fly ash monitor that could be adapted to measure either a thermal-acoustic or thermal-elastic response to due microwave excitation of fly ash. The thermal-acoustic response was successfully employed for this purpose but the thermal-elastic response was too weak to yield a useful on-line device.

Robert C. Brown; Robert J. Weber; Jeffrey J. Swetelitsch

2005-01-01T23:59:59.000Z

116

Measurement of Thermal Conductivity of PbTe Nanocrystal Coated Glass Fibers by the 3 Method  

E-Print Network [OSTI]

and high aspect ratio result in a significant thermal radiation effect. We simulate the experiment using such as automobile exhaust pipes, power plant steam pipes, manufacturing industry cooling pipes, and so forth. Our the radiation effect and extract the thermal conductivity at the single fiber level. Our simulation method

Ruan, Xiulin

117

Evolution of a double-front Rayleigh-Taylor system using a GPU-based high resolution thermal Lattice-Boltzmann model  

E-Print Network [OSTI]

We study the turbulent evolution originated from a system subjected to a Rayleigh-Taylor instability with a double density at high resolution in a 2 dimensional geometry using a highly optimized thermal Lattice Boltzmann code for GPUs. The novelty of our investigation stems from the initial condition, given by the superposition of three layers with three different densities, leading to the development of two Rayleigh-Taylor fronts that expand upward and downward and collide in the middle of the cell. By using high resolution numerical data we highlight the effects induced by the collision of the two turbulent fronts in the long time asymptotic regime. We also provide details on the optimized Lattice-Boltzmann code that we have run on a cluster of GPUs

Ripesi, P; Schifano, S F; Tripiccione, R

2014-01-01T23:59:59.000Z

118

Simbol-X Mirror Module Thermal Shields: II-Small Angle X-Ray Scattering Measurements  

SciTech Connect (OSTI)

The formation flight configuration of the Simbol-X mission implies that the X-ray mirror module will be open to Space on both ends. In order to reduce the power required to maintain the thermal stability and, therefore, the high angular resolution of the shell optics, a thin foil thermal shield will cover the mirror module. Different options are presently being studied for the foil material of these shields. We report results of an experimental investigation conducted to verify that the scattering of X-rays, by interaction with the thin foil material of the thermal shield, will not significantly affect the performances of the telescope.

Barbera, M. [Universita degli Studi di Palermo, Dip. di Scienze Fisiche ed Astronomiche, Palermo (Italy); Istituto Nazionale di Astrofisica-Osservatorio Astronomico di Palermo G.S. Vaiana, Palermo (Italy); Ayers, T. [Luxel Corporation, Friday Harbor (WA) (United States); Collura, A. [Istituto Nazionale di Astrofisica-Osservatorio Astronomico di Palermo G.S. Vaiana, Palermo (Italy); Nasillo, G. [Universita degli Studi di Palermo, Centro Grandi Apparecchiature, Palermo (Italy); Pareschi, G.; Tagliaferri, G. [Istituto Nazionale di Astrofisica-Osservatorio Astronomico di Brera, Merate (Italy)

2009-05-11T23:59:59.000Z

119

Measurement of the fluence response of the GSI neutron ball dosemeter in the energy range from thermal to 19 MeV  

Science Journals Connector (OSTI)

......the GKSS research reactor FRG-1 in Geesthacht. For the accelerator measurements...thermal neutrons was performed at the Geesthacht Neutron Facility (GeNF) laboratory...the GKSS research reactor FRG-1 in Geesthacht. For the accelerator measurements......

G. Fehrenbacher; E. Kozlova; F. Gutermuth; T. Radon; R. Schtz; R. Nolte; R. Bttger

2007-08-01T23:59:59.000Z

120

Experimentally measured thermal transport properties of aluminumpolytetrafluoroethylene nanocomposites with graphene and carbon nanotube additives  

Science Journals Connector (OSTI)

Reactive materials such as aluminum (Al) and polytetrafluoroethylene (Teflon) are used for energy generation applications and specifically in ordnance technologies. With the advent of nanotechnology various nano-scale additives have become incorporated into reactive material formulations with the hope of enhanced performance. An important component to the study of energy generation is an examination of energy transport through a reactant matrix. This study examines an experimental approach to quantifying thermal properties of an Al/Teflon nanocomposite reactant matrix that has been impregnated with carbon additives. Various structures of carbon are investigated and include amorphous nanoscale carbon spheres (nano C), graphene flakes and unaligned multiwalled carbon nanotubes (CNTs). The additives were selected based on their completely different structures with the hypothesis that the structure of the additive will influence the thermal transport properties of the matrix. Results show graphene has the greatest influence on the thermophysical properties. For example, thermal conductivity of the composites containing graphene increased by 98%. Graphene similarly enhanced the thermal diffusivity and specific heat of the Al/Teflon matrix. Conversely, nano C and \\{CNTs\\} decreased the thermal conductivity and thermal diffusivity of the samples significantly.

Keerti Kappagantula; Michelle L. Pantoya

2012-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "measuring thermal evolution" 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

An optimal guarding scheme for thermal conductivity measurement using a guarded cut-bar technique, part 1 experimental study  

SciTech Connect (OSTI)

In the guarded cut-bar technique, a guard surrounding the measured sample and reference (meter) bars is temperature controlled to carefully regulate heat losses from the sample and reference bars. Guarding is typically carried out by matching the temperature profiles between the guard and the test stack of sample and meter bars. Problems arise in matching the profiles, especially when the thermal conductivitiesof the meter bars and of the sample differ, as is usually the case. In a previous numerical study, the applied guarding condition (guard temperature profile) was found to be an important factor in measurement accuracy. Different from the linear-matched or isothermal schemes recommended in literature, the optimal guarding condition is dependent on the system geometry and thermal conductivity ratio of sample to meter bar. To validate the numerical results, an experimental study was performed to investigate the resulting error under different guarding conditions using stainless steel 304 as both the sample and meter bars. The optimal guarding condition was further verified on a certified reference material, pyroceram 9606, and 99.95% pure iron whose thermal conductivities are much smaller and much larger, respectively, than that of the stainless steel meter bars. Additionally, measurements are performed using three different inert gases to show the effect of the insulation effective thermal conductivity on measurement error, revealing low conductivity, argon gas, gives the lowest error sensitivity when deviating from the optimal condition. The result of this study provides a general guideline for the specific measurement method and for methods requiring optimal guarding or insulation.

Changhu Xing [Utah State Univ., Logan, UT (United States). Dept. of Mechanical and Aerospace Engineering; Colby Jensen [Utah State Univ., Logan, UT (United States). Dept. of Mechanical and Aerospace Engineering; Charles Folsom [Utah State Univ., Logan, UT (United States). Dept. of Mechanical and Aerospace Engineering; Heng Ban [Utah State Univ., Logan, UT (United States). Dept. of Mechanical and Aerospace Engineering; Douglas W. Marshall [Idaho National Laboratory (INL), Idaho Falls, ID (United States)

2014-01-01T23:59:59.000Z

122

A Correction Scheme for Thermal Conductivity Measurement Using the Comparative Cut-bar Technique Based on a 3D Numerical Simulation  

SciTech Connect (OSTI)

As an important factor affecting the accuracy of the thermal conductivity measurement, systematic (bias) error in the guarded comparative axial heat flow (cut-bar) method was mostly neglected by previous researches. This bias is due primarily to the thermal conductivity mismatch between sample and meter bars (reference), which is common for a sample of unknown thermal conductivity. A correction scheme, based on a finite element simulation of the measurement system, was proposed to reduce the magnitude of the overall measurement uncertainty. This scheme was experimentally validated by applying corrections on four types of sample measurements in which the specimen thermal conductivity is much smaller, slightly smaller, equal and much larger than that of the meter bar. As an alternative to the optimum guarding technique proposed before, the correction scheme can be used to minimize uncertainty contribution from the measurement system with non-optimal guarding conditions. It is especially necessary for large thermal conductivity mismatches between sample and meter bars.

Douglas W. Marshall; Changhu Xing; Charles Folsom; Colby Jensen; Heng Ban

2014-05-01T23:59:59.000Z

123

Thermal imaging measurement of lateral diffusivity and non-invasive material defect detection  

DOE Patents [OSTI]

A system and method for determining lateral thermal diffusivity of a material sample using a heat pulse; a sample oriented within an orthogonal coordinate system; an infrared camera; and a computer that has a digital frame grabber, and data acquisition and processing software. The mathematical model used within the data processing software is capable of determining the lateral thermal diffusivity of a sample of finite boundaries. The system and method may also be used as a nondestructive method for detecting and locating cracks within the material sample.

Sun, Jiangang (Westmont, IL); Deemer, Chris (Downers Grove, IL)

2003-01-01T23:59:59.000Z

124

American Institute of Aeronautics and Astronautics Measurements for fuel reforming for scramjet thermal management and  

E-Print Network [OSTI]

of liquid hydrocarbon halved)3 . When heated and pyrolysed, it produces lighter hydrocarbons species thermal management and combustion optimization : 2009 status of the COMPARER project. Gregory. ABRAHAM1. But even CMC materials could not withstand such large heat loads (for example, total temperature

Paris-Sud XI, Université de

125

Building design and thermal renovation measures proposal by means of regression models issued from dynamic simulations  

E-Print Network [OSTI]

comparison between different energy reduction strategies, like improving the insulation levels or increasing the thermal inertia. An example of their use and a data comparison with a dynamic simulation is shown in last;Nowadays, the most reliable solutions to calculate the energy demand are the simulation energy tools

Boyer, Edmond

126

IN-SITU MEASUREMENT OF WALL THERMAL PERFORMANCE: DATA INTERPRETATION AND APPARATUS DESIGN RECOMMENDATIONS  

E-Print Network [OSTI]

Unit (ETTU): Field Measurement of Wall Performance, Presented at Third International Symposium on Energy

Modera, M.P.; Sherman, M.H.; de Vinuesa, S.G.

2008-01-01T23:59:59.000Z

127

Pressure Wave Measurements Resulting from Thermal Cook-Off of the HMX Based High Explosive LX-04  

SciTech Connect (OSTI)

Experiments that investigate thermal and nearby explosion scenarios are needed to provide essential data to models for accurate predictions. A porous LX-04 (85/15 wt% HMX/Viton) sample was heated in a heavily confined donor charge until it thermally exploded. The reaction accelerated a steel cover plate across a 10 cm gap into a preheated gauged acceptor cylinder (near its theoretical maximum density) of LX-04. The carbon resistor gauges in the acceptor measured the resulting multi-dimensional ramp wave as it propagated through the pre-heated LX-04. Detonation of the LX-04 acceptor does not occur. Results are compared to similar experiments with acceptors at room temperature.

Garcia, F; Vandersall, K S; Forbes, J W; Tarver, C M; Greenwood, D

2003-07-11T23:59:59.000Z

128

Measurement and modeling of thermal properties of sorghum and soy flours  

E-Print Network [OSTI]

Kelvin. Figure 1 shows the OSC conventions for presentation of thermal analysis data. When a transition such as melting, boiling, gelatinization or crystallization occurs in the sample material, an endothermic or exothermic reaction takes place... important than the second scan values. The second scan values, however, can tell us whether endothermic or exothermic transitions occurred in the first scan and 1f these transitions are irreversible. The bas1c methodology for determining specific heat...

Gonzalez Palacios, Lazaro

1981-01-01T23:59:59.000Z

129

Proc. Fifteenth IEEE Semiconductor Thermal Measurement and Management Symposium, March 9-11, 1999, San Diego CA, IEEE # 99CH36306.  

E-Print Network [OSTI]

Proc. Fifteenth IEEE Semiconductor Thermal Measurement and Management Symposium, March 9-11, 1999, San Diego CA, IEEE # 99CH36306. 74 THERMAL MANAGEMENT USING "DRY" PHASE CHANGE MATERIALS R.A. Wirtz" PCM unit conductance D Heat sink depth htr Heat of transition H Fin height Hpcm PCM mass depth kal

Wirtz, Richard A.

130

Measurements of continuous mix evolution in a high energy density shear flow  

SciTech Connect (OSTI)

We report on the novel integration of streaked radiography into a counter-flowing High Energy Density (HED) shear environment that continually measures a growing mix layer of Al separating two low-density CH foams. Measurements of the mix width allow us to validate compressible turbulence models and with streaked imaging, make this possible with a minimal number of experiments on large laser facilities. In this paper, we describe how the HED counter-flowing shear layer is created and diagnosed with streaked radiography. We then compare the streaked data to previous two-dimensional, single frame radiography and radiation hydrodynamic simulations of the experiment with inline compressible turbulent mix models.

Loomis, E., E-mail: loomis@lanl.gov; Doss, F.; Flippo, K.; Fincke, J. [Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States)] [Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States)

2014-04-15T23:59:59.000Z

131

Photo-Thermal Transfer Function of Dielectric Mirrors for Precision Measurements  

E-Print Network [OSTI]

The photo-thermal transfer function from absorbed power incident on a dielectric mirror to the effective mirror position is calculated using the coating design as input. The effect is found to change in amplitude and sign for frequencies corresponding to diffusion length comparable to the coating thickness. Transfer functions are calculated for the $Ti$-doped ${\\rm Ta_2O_5:SiO_2}$ coating used in Advanced LIGO and for a crystalline ${\\rm Al_xGa_{1-x}As}$ coating. The shape of the transfer function at high frequencies is shown to be a sensitive indicator of the effective absorption depth, providing a potentially powerful tool to distinguish coating-internal absorption from surface contamination related absorption. The sign change of the photo-thermal effect could also be useful to stabilize radiation pressure-based opto-mechanical systems. High frequency corrections to the previously published thermo-optic noise estimates are also provided. Finally, estimating the quality of the thermo-optic noise cancellation occurring in fine-tuned ${\\rm Al_xGa_{1-x}As}$ coatings requires the detailed heat flow analysis done in this paper.

Stefan W. Ballmer

2014-11-10T23:59:59.000Z

132

Photo-Thermal Transfer Function of Dielectric Mirrors for Precision Measurements  

E-Print Network [OSTI]

The photo-thermal transfer function from absorbed power incident on a dielectric mirror to the effective mirror position is calculated using the coating design as input. The effect is found to change in amplitude and sign for frequencies corresponding to diffusion length comparable to the coating thickness. Transfer functions are calculated for the $Ti$-doped ${\\rm Ta_2O_5:SiO_2}$ coating used in Advanced LIGO and for a crystalline ${\\rm Al_xGa_{1-x}As}$ coating. The shape of the transfer function at high frequencies is shown to be a sensitive indicator of the effective absorption depth, providing a potentially powerful tool to distinguish coating-internal absorption from surface contamination related absorption. The sign change of the photo-thermal effect could also be useful to stabilize radiation pressure-based opto-mechanical systems. High frequency corrections to the previously published thermo-optic noise estimates are also provided. Finally, estimating the quality of the thermo-optic noise cancellation occurring in fine-tuned ${\\rm Al_xGa_{1-x}As}$ coatings requires the detailed heat flow analysis done in this paper.

Stefan W. Ballmer

2015-01-07T23:59:59.000Z

133

Cryogenic measurements of mechanical loss of high-reflectivity coating and estimation of thermal noise  

Science Journals Connector (OSTI)

We report on low-frequency measurements of the mechanical loss of a high-quality (transmissivity T<5??ppm at ?0=1064??nm, absorption...

Granata, Massimo; Craig, Kieran; Cagnoli, Gianpietro; Carcy, Ccile; Cunningham, William; Degallaix, Jrme; Flaminio, Raffaele; Forest, Danile; Hart, Martin; Hennig, Jan-Simon; Hough, James; MacLaren, Ian; Martin, Iain William; Michel, Christophe; Morgado, Nazario; Otmani, Salim; Pinard, Laurent; Rowan, Sheila

2013-01-01T23:59:59.000Z

134

Measuring the evolution of the most stable optical clock G 117-B15A  

E-Print Network [OSTI]

We report our measurement of the rate of change of period with time dP/dt for the 215 s periodicity in the pulsating white dwarf G 117-B15A, the most stable optical clock known. After 31 years of observations, we have finally obtained a 4 sigma measurement dP/dt_observed = (4.27 +/- 0.80) x 10^{-15} s/s. Taking into account the proper-motion effect of dP/dt_pm = (7.0 +/- 2.0) x 10^{-16} s/s, we obtain a rate of change of period with time of dP/dt = (3.57 +/- 0.82) x 10^{-15} s/s. This value is consistent with the cooling rate in our white dwarf models only for cores of C or C/O. With the refinement of the models, the observed rate of period change can be used to accurately measure the ratio of C/O in the core of the white dwarf.

S. O. Kepler; J. E. S. Costa; B. G. Castanheira; D. E. Winget; Fergal Mullally; R. E. Nather; Mukremin Kilic; Ted von Hippel; Anjum S. Mukadam; Denis J. Sullivan

2005-07-20T23:59:59.000Z

135

Calculations of thermal-reactor spent-fuel nuclide inventories and comparisons with measurements  

SciTech Connect (OSTI)

Comparisons with integral measurements have demonstrated the accuracy of CINDER codes and libraries in calculating aggregate fission-product properties, including neutron absorption, decay power, and decay spectra. CINDER calculations have, alternatively, been used to supplement measured integral data describing fission-product decay power and decay spectra. Because of the incorporation of the extensive actinide library and the use of ENDF/B-V data, it is desirable to compare the inventory of individual nuclides obtained from tandem EPRI-CELL/CINDER-2 calculations with those determined in documented benchmark inventory measurements of spent reactor fuel. The development of the popular /sup 148/Nd burnup measurement procedure is outlined, and areas of uncertainty in it and lack of clarity in its interpretation are indicated. Six inventory samples of varying quality and completeness are examined. The power histories used in the calculations have been listed for other users.

Wilson, W.B.; LaBauve, R.J.; England, T.R.

1982-01-01T23:59:59.000Z

136

American Institute of Aeronautics and Astronautics Measurements for fuel reforming for scramjet thermal management and  

E-Print Network [OSTI]

American Institute of Aeronautics and Astronautics 1 Measurements for fuel reforming for scramjet, since even composite materials can't withstand the large heat load found in a Scramjet combustion

Paris-Sud XI, Université de

137

Measurements of the spatial and energy distribution of thermal neutrons in uranium, heavy water lattices  

E-Print Network [OSTI]

Intracell activity distributions were measured in three natural uranium, heavy water lattices of 1. 010 inch diameter, aluminum clad rods on triangular spacings of 4. 5 inches, 5. 0 inches, and 5. 75 inches, respectively, ...

Brown, Paul S. (Paul Sherman)

1962-01-01T23:59:59.000Z

138

Structure and thermal regime beneath the South Pole region, East Antarctica, from magnetotelluric measurements  

Science Journals Connector (OSTI)

......Figure B2 Recordings of electric fields on parallel...a superposition of elementary volumes (e.g. Stratton...spherical distribution of electric charge over the Earth's...of electrode contact resistance on electric field measurements......

Philip E. Wannamaker; John A. Stodt; Louise Pellerin; Steven L. Olsen; Darrell B. Hall

2004-04-01T23:59:59.000Z

139

Thermalization through parton transport  

E-Print Network [OSTI]

A radiative transport model is used to study kinetic equilibration during the early stage of a relativistic heavy ion collision. The parton system is found to be able to overcome expansion and move toward thermalization via parton collisions. Scaling behaviors show up in both the pressure anisotropy and the energy density evolutions. In particular, the pressure anisotropy evolution shows an approximate alpha_s scaling when radiative processes are included. It approaches an asymptotic time evolution on a time scale of 1 to 2 fm/c. The energy density evolution shows an asymptotic time evolution that decreases slower than the ideal hydro evolution. These observations indicate that partial thermalization can be achieved and viscosity is important for the evolution during the early longitudinal expansion stage of a relativistic heavy ion collision.

Bin Zhang

2009-09-03T23:59:59.000Z

140

Rotational Corrections to Neutron-Star Radius Measurements from Thermal Spectra  

E-Print Network [OSTI]

We calculate the rotational broadening in the observed thermal spectra of neutron stars spinning at moderate rates in the Hartle-Thorne approximation. These calculations accurately account for the effects of the second-order Doppler boosts as well as for the oblate shapes and the quadrupole moments of the neutron stars. We find that fitting the spectra and inferring the bolometric fluxes under the assumption that a star is not rotating causes an underestimate of the inferred fluxes and, thus, radii. The correction depends on the stellar spin, radius, and observer's inclination. For a 10 km neutron star spinning at 600 Hz, the rotational correction to the flux is ~1-4%, while for a 15 km neutron star with the same spin period, the correction ranges from 2% for pole-on sources to 12% for edge-on sources. We calculate the inclination-averaged corrections to inferred radii as a function of the neutron-star radius and mass and provide an empirical formula for the corrections. For realistic neutron star parameters (1.4 M$_\\odot$, 12 km, 600 Hz), the stellar radius is on the order of 4% larger than the radius inferred under the assumption that the star is not spinning.

Michi Baubock; Feryal Ozel; Dimitrios Psaltis; Sharon M. Morsink

2014-07-11T23:59:59.000Z

Note: This page contains sample records for the topic "measuring thermal evolution" 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

Rotational Corrections to Neutron-Star Radius Measurements from Thermal Spectra  

E-Print Network [OSTI]

We calculate the rotational broadening in the observed thermal spectra of neutron stars spinning at moderate rates in the Hartle-Thorne approximation. These calculations accurately account for the effects of the second-order Doppler boosts as well as for the oblate shapes and the quadrupole moments of the neutron stars. We find that fitting the spectra and inferring the bolometric fluxes under the assumption that a star is not rotating causes an underestimate of the inferred fluxes and, thus, radii. The correction depends on the stellar spin, radius, and observer's inclination. For a 10 km neutron star spinning at 600 Hz, the rotational correction to the flux is ~1-4%, while for a 15 km neutron star with the same spin period, the correction ranges from 2% for pole-on sources to 12% for edge-on sources. We calculate the inclination-averaged corrections to inferred radii as a function of the neutron-star radius and mass and provide an empirical formula for the corrections. For realistic neutron star parameters ...

Baubock, Michi; Psaltis, Dimitrios; Morsink, Sharon M

2014-01-01T23:59:59.000Z

142

Measurement of the electronic thermal conductance channels and heat capacity of graphene at low temperature  

E-Print Network [OSTI]

opto-electronics, plasmonics, and ultra-sensitive bolometry. Here we present measurements of bipolar con- ductance over a temperature range of 300 mK to 100 K, using three different sample configurations of 10-20 J/K at 300 mK, which is 9 times smaller than the previous record[15]. For higher temperatures

143

First Measurements of the Inclined Boron Layer Thermal-Neutron Detector for Reflectometry  

SciTech Connect (OSTI)

A prototype detector based on the inclined boron layer principle is introduced. For typical measurement conditions at the Liquids Reflectometer at the Spallation Neutron Source, its count rate capability is shown to be superior to that of the current detector by nearly two orders of magnitude.

Clonts, Lloyd G [ORNL; Crow, Lowell [ORNL; Van Vuure, Thorwald L [ORNL; Robertson, Lee [ORNL; Riedel, Richard A [ORNL; Richards, John D [ORNL; Cooper, Ronald G [ORNL; Remec, Igor [ORNL; Ankner, John Francis [ORNL; Browning, Jim [ORNL

2010-01-01T23:59:59.000Z

144

COMBINED THERMAL MEASUREMENT AND SIMULATION FOR THE DETAILED ANALYSIS OF FOUR OCCUPIED LOW-ENERGY BUILDINGS  

E-Print Network [OSTI]

-ENERGY BUILDINGS U.D.J. Gieseler, F.D. Heidt1 , W. Bier Division of Building Physics and Solar Energy, University energy and temperature measurements of occupied buildings very well. These buildings repre- sent small to medium size residential low-energy buildings of different construction type, which are typical for mid

Gieseler, Udo D. J.

145

MULTI-WAVELENGTH OBSERVATIONS OF THE SPATIO-TEMPORAL EVOLUTION OF SOLAR FLARES WITH AIA/SDO. II. HYDRODYNAMIC SCALING LAWS AND THERMAL ENERGIES  

SciTech Connect (OSTI)

In this study we measure physical parameters of the same set of 155 M- and X-class solar flares observed with AIA/SDO as analyzed in Paper I, by performing a differential emission measure analysis to determine the flare peak emission measure EM{sub p} , peak temperature T{sub p} , electron density n{sub p} , and thermal energy E{sub th}, in addition to the spatial scales L, areas A, and volumes V measured in Paper I. The parameter ranges for M- and X-class flares are log (EM{sub p}) = 47.0-50.5, T{sub p} = 5.0-17.8 MK, n{sub p} = 4 10{sup 9}-9 10{sup 11} cm{sup 3}, and thermal energies of E{sub th} = 1.6 10{sup 28}-1.1 10{sup 32} erg. We find that these parameters obey the Rosner-Tucker-Vaiana (RTV) scaling law T{sub p}{sup 2}?n{sub p} L and H?T {sup 7/2} L {sup 2} during the peak time t{sub p} of the flare density n{sub p} , when energy balance between the heating rate H and the conductive and radiative loss rates is achieved for a short instant and thus enables the applicability of the RTV scaling law. The application of the RTV scaling law predicts power-law distributions for all physical parameters, which we demonstrate with numerical Monte Carlo simulations as well as with analytical calculations. A consequence of the RTV law is also that we can retrieve the size distribution of heating rates, for which we find N(H)?H {sup 1.8}, which is consistent with the magnetic flux distribution N(?)??{sup 1.85} observed by Parnell et al. and the heating flux scaling law F{sub H} ?HL?B/L of Schrijver et al.. The fractal-diffusive self-organized criticality model in conjunction with the RTV scaling law reproduces the observed power-law distributions and their slopes for all geometrical and physical parameters and can be used to predict the size distributions for other flare data sets, instruments, and detection algorithms.

Aschwanden, Markus J. [Lockheed Martin Advanced Technology Center, Org. ADBS, Bldg. 252, 3251 Hanover St., Palo Alto, CA 94304 (United States); Shimizu, Toshifumi, E-mail: aschwanden@lmsal.com, E-mail: shimizu.toshifumi@isas.jaxa.jp [Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency, 3-1-1 Yoshinodai, Chuo, Sagamihara, Kanagawa 252-5210 (Japan)

2013-10-20T23:59:59.000Z

146

Note: A simple model for thermal management in solenoids  

SciTech Connect (OSTI)

We describe a model of the dynamical temperature evolution in a solenoid winding. A simple finite element analysis is calibrated by accurately measuring the thermally induced resistance change of the solenoid, thus obviating the need for accurate knowledge of the mean thermal conductivity of the windings. The model predicts quasi thermal runaway for relatively modest current increases from the normal operating conditions. We demonstrate the application of this model to determine the maximum current that can be safely applied to solenoids used for helium spin-echo measurements.

McIntosh, E. M., E-mail: emb56@cam.ac.uk; Ellis, J. [The Cavendish Laboratory, JJ Thomson Avenue, Cambridge CB3 0HE (United Kingdom)] [The Cavendish Laboratory, JJ Thomson Avenue, Cambridge CB3 0HE (United Kingdom)

2013-11-15T23:59:59.000Z

147

Measurements of thermal-hydraulic parameters in liquid-metal-cooled fast-breeder reactors  

SciTech Connect (OSTI)

This paper discusses instrumentation for liquid-metal-cooled fast breeder reactors (LMFBR's). Included is instrumentation to measure sodium flow, pressure, temperature, acoustic noise, sodium purity, and leakage. The paper identifies the overall instrumentation requirements for LMFBR's and those aspects of instrumentation which are unique or of special concern to LMFBR systems. It also gives an overview of the status of instrument design and performance.

Sackett, J.I.

1983-01-01T23:59:59.000Z

148

Research options for the development of sensors to measure the thermal state of solid steel bodies.  

SciTech Connect (OSTI)

The purpose of the study reported here is to assist Battelle's Pcacific Northwest Laboratory (PNL) in planning a research and development program to develop temperature sensors for metal and ceramic industries. This study focuses on sensors to measure internal temperatures within bodies of hot steel. A series of literature surveys, interviews, field visits, and meetings with steel-industry organizations was conducted in seeking answers to questions posed by PNL. These questions, with responses, are summarized.

Gaspar, T.A.; Lownie, H.W. Jr.

1983-02-01T23:59:59.000Z

149

Gamma-gamma directional correlation measurements in 130,132Xe following thermal neutron capture by natural xenon  

Science Journals Connector (OSTI)

Directional correlations of gamma-ray cascades in 130,132Xe have been measured following thermal n capture by a pressurised natural xenon gas target. Gamma-ray singles spectra were measured up to 5.5 MeV and the coincidence correlation data were obtained for the energy range 0.2-2.5 MeV. Decay schemes were developed on the basis of the coincidence measurements. The data spin-parity assignments to be made to most levels lying below 3.5 MeV in the 132Xe and the multiple mixing ratios to be evaluated for the more intense transitions. The results are fitted to IBM-1 and IBM-2 and are also compared with the prediction of the dynamic deformation model of Kumar (1983). The 23+ level at 1985 keV in 132Xe is considered to be a mixed-symmetry state with B(M1; 23+ to 21+)=0.29 mu N2.

S A Hamada; W D Hamilton; B More

1988-01-01T23:59:59.000Z

150

High-resolution thermal-expansion measurements of tetrathiafulvalenetetracyanoquinodimethane (TTF-TCNQ)  

Science Journals Connector (OSTI)

An analysis of our measurements of the b-axis expansivity ?b of tetrathiafulvalene-tetracyanoquinodimethane (TTF-TCNQ) within the Debye approximation suggests an unexpectedly high effective Debye temperature (?b=20030 K) and a large anharmonicity (?=51.5) for the low-lying b-axis polarized acoustic phonons. These values for ? and ?b indicate substantial softening of the lattice above 100 K and also suggest an expansivity contribution from intramolecular vibrational modes. No anomalous length changes were observed in the region of the metal-semiconductor transition (45-65 K) to within ?LbLb?310-5.

D. E. Schafer; G. A. Thomas; F. Wudl

1975-12-15T23:59:59.000Z

151

Measuring the Optical Performance of Evacuated Receivers via an Outdoor Thermal Transient Test: Preprint  

SciTech Connect (OSTI)

Modern parabolic trough solar collectors operated at high temperatures to provide the heat input to Rankine steam power cycles employ evacuated receiver tubes along the collector focal line. High performance is achieved via the use of a selective surface with a high absorptance for incoming short-wave solar radiation and a low emittance for outgoing long-wave infrared radiation, as well as the use of a hard vacuum to essentially eliminate convective and conductive heat losses. This paper describes a new method that determines receiver overall optical efficiency by exposing a fluid-filled, pre-cooled receiver to one sun outdoors and measuring the slope of the temperature curve at the point where the receiver temperature passes the glass envelope temperature (that is, the point at which there is no heat gain or loss from the absorber). This transient test method offers the potential advantages of simplicity, high accuracy, and the use of the actual solar spectrum.

Kutscher, C.; Burkholder, F.; Netter, J.

2011-08-01T23:59:59.000Z

152

Observation and Measurement of Temperature Rise and Distribution on GaAs Photo-cathode Wafer with a 532nm Drive Laser and a Thermal Imaging Camera  

SciTech Connect (OSTI)

Significant temperature rise and gradient are observed from a GaAs photo-cathode wafer irradiated at various power levels with over 20W laser power at 532nm wavelength. The laser power absorption and dissipated thermal distribution are measured. The result shows a clear indication that proper removal of laser induced heat from the cathode needs to be considered seriously when designing a high average current or low quantum efficiency photo-cathode electron gun. The measurement method presented here provides a useful way to obtain information about both temperature and thermal profiles, it also applies to cathode heating study with other heating devices such as electrical heaters.

Shukui Zhang, Stephen Benson, Carlos Hernandez-Garcia

2011-03-01T23:59:59.000Z

153

Evolution of microstructure and residual stress in disc-shape EB-PVD thermal barrier coatings and temperature profile of high pressure turbine blade.  

E-Print Network [OSTI]

??A detailed understanding of failure mechanisms in thermal barrier coatings (TBCs) can help develop reliable and durable TBCs for advanced gas turbine engines. One of (more)

Mukherjee, Sriparna

2011-01-01T23:59:59.000Z

154

Comparison of the effects of long-term thermal aging and HFIR irradiation on the microstructural evolution of 9Cr-1MoVNb steel  

SciTech Connect (OSTI)

Both thermal aging at 482--704{degree}C for up to 25,000h and HFIR irradiation at 300--600{degree}C for up to 39 dpa produce substantial changes in the as-tempered microstructure of 9Cr-1MoVNb martensitic/ferritic steel. However, the changes in the dislocation/subgrain boundary and the precipitate structures caused by thermal aging or neutron irradiation are quite different in nature. During thermal aging, the as-tempered lath/subgrain boundary and carbide precipitate structures remain stable below 650{degree}C, but coarsen and recover somewhat at 650--704{degree}C. The formation of abundant intergranular Laves phase, intra-lath dislocation networks, and fine dispersions of VC needles are thermal aging effects that are superimposed upon the as-tempered microstructure at 482--593{degree}C. HFIR irradiation produces dense dispersions of very small black-dot'' dislocations loops at 300{degree}C and produces helium bubbles and voids at 400{degree}C At 300--500{degree}C, there is considerable recovery of the as-tempered lath/subgrain boundary structure and microstructural/microcompositional instability of the as-tempered carbide precipitates during irradiation. By contrast, the as-tempered microstructure remains essentially unchanged during irradiation at 600{degree}C. Comparison of thermally aged with irradiation material suggests that the instabilities of the as-tempered lath/subgrain boundary and precipitate structures at lower irradiation temperatures are radiation-induced effects, whereas the absence of both Laves phase and fine VC needles during irradiation is a radiation-retarded thermal effect.

Maziasz, P.J.; Klueh, R.L.

1990-01-01T23:59:59.000Z

155

Feasibility study for measurement of insulation compaction in the cryogenic rocket fuel storage tanks at Kennedy Space Center by fast/thermal neutron techniques  

SciTech Connect (OSTI)

The liquid hydrogen and oxygen cryogenic storage tanks at John F. Kennedy Space Center (KSC) use expanded perlite as thermal insulation. Some of the perlite may have compacted over time, compromising the thermal performance and also the structural integrity of the tanks. Neutrons can readily penetrate through the 1.75 cm outer steel shell and through the entire 120 cm thick perlite zone. Neutrons interactions with materials produce characteristic gamma rays which are then detected. In compacted perlite the count rates in the individual peaks in the gamma ray spectrum will increase. Portable neutron generators can produce neutron simultaneous fluxes in two energy ranges: fast (14 MeV) and thermal (25 meV). Fast neutrons produce gamma rays by inelastic scattering which is sensitive to Si, Al, Fe and O. Thermal neutrons produce gamma rays by radiative capture in prompt gamma neutron activation (PGNA), which is sensitive to Si, Al, Na, K and H among others. The results of computer simulations using the software MCNP and measurements on a test article suggest that the most promising approach would be to operate the system in time-of-flight mode by pulsing the neutron generator and observing the subsequent die away curve in the PGNA signal.

Livingston, R. A. [Materials Science and Engineering Dept., U. of Maryland, College Park, MD (United States); Schweitzer, J. S. [Physics Dept., U. of Connecticut, Storrs (United States); Parsons, A. M. [Goddard Space Flight Center, Greenbelt (United States); Arens, E. E. [John F. Kennedy Space Center, FL (United States)

2014-02-18T23:59:59.000Z

156

Thermal neutron detection system  

DOE Patents [OSTI]

According to the present invention, a system for measuring a thermal neutron emission from a neutron source, has a reflector/moderator proximate the neutron source that reflects and moderates neutrons from the neutron source. The reflector/moderator further directs thermal neutrons toward an unmoderated thermal neutron detector.

Peurrung, Anthony J. (Richland, WA); Stromswold, David C. (West Richland, WA)

2000-01-01T23:59:59.000Z

157

Measurements of gamma dose and thermal neutron fluence in phantoms exposed to a BNCT epithermal beam with TLD-700  

Science Journals Connector (OSTI)

......epithermal neutron beam for boron neutron capture therapy...separation. INTRODUCTION Boron neutron capture therapy...accumulation of the isotope 10B in tumour tissue...necessary and that for the determination of the ratio R n, a...Carrara M., Borroni M. Determination of gamma dose and thermal......

G. Gambarini; D. Magni; V. Regazzoni; M. Borroni; M. Carrara; E. Pignoli; J. Burian; M. Marek; V. Klupak; L. Viererbl

2014-10-01T23:59:59.000Z

158

Measurement of Three Critical Parameters as a Basis for a Simple Thermal Barrier Coating Life Prediction Methodology  

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

Three Critical Parameters Three Critical Parameters As A Basis for A Simple Thermal Barrier Coating Life Prediction Methodology University of Connecticut Eric Jordan and Maurice Gell SCIES Project 02- 01- SR 097 DOE COOPERATIVE AGREEMENT DE-FC26-02NT41431 Tom J. George, Program Manager, DOE/NETL Richard Wenglarz, Manager of Research, SCIES Project Awarded (05/01/02, 36 Month Duration) $ 478,495 Total Contract Value ($ 478,495 DOE) Gas Turbine Need * Industrial Gas Turbine Performance & Durability Depend Strongly On Use Of Thermal Barrier Coatings * Aggressive Application of TBCs Limited By Lack of NDI And Lifing Methods University of Connecticut Gas Turbine Need Non-Destructive Assessment of Remaining Life Strongly Impacts Operating Cost * Reduce occurrence of unplanned shut down * Reduce wasteful precautionary part replacement

159

Fission Product Data Measured at Los Alamos for Fission Spectrum and Thermal Neutrons on {sup 239}Pu, {sup 235}U, {sup 238}U  

SciTech Connect (OSTI)

We describe measurements of fission product data at Los Alamos that are important for determining the number of fissions that have occurred when neutrons are incident on plutonium and uranium isotopes. The fission-spectrum measurements were made using a fission chamber designed by the National Institute for Standards and Technology (NIST) in the BIG TEN critical assembly, as part of the Inter-laboratory Liquid Metal Fast Breeder Reactor (LMFBR) Reaction Rate (ILRR) collaboration. The thermal measurements were made at Los Alamos' Omega West Reactor. A related set of measurements were made of fission-product ratios (so-called R-values) in neutron environments provided by a number of Los Alamos critical assemblies that range from having average energies causing fission of 400-600 keV (BIG TEN and the outer regions of the Flattop-25 assembly) to higher energies (1.4-1.9 MeV) in the Jezebel, and in the central regions of the Flattop-25 and Flattop-Pu, critical assemblies. From these data we determine ratios of fission product yields in different fuel and neutron environments (Q-values) and fission product yields in fission spectrum neutron environments for {sup 99}Mo, {sup 95}Zr, {sup 137}Cs, {sup 140}Ba, {sup 141,143}Ce, and {sup 147}Nd. Modest incident-energy dependence exists for the {sup 147}Nd fission product yield; this is discussed in the context of models for fission that include thermal and dynamical effects. The fission product data agree with measurements by Maeck and other authors using mass-spectrometry methods, and with the ILRR collaboration results that used gamma spectroscopy for quantifying fission products. We note that the measurements also contradict earlier 1950s historical Los Alamos estimates by {approx}5-7%, most likely owing to self-shielding corrections not made in the early thermal measurements. Our experimental results provide a confirmation of the England-Rider ENDF/B-VI evaluated fission-spectrum fission product yields that were carried over to the ENDF/B-VII.0 library, except for {sup 99}Mo where the present results are about 4%-relative higher for neutrons incident on {sup 239}Pu and {sup 235}U. Additionally, our results illustrate the importance of representing the incident energy dependence of fission product yields over the fast neutron energy range for high-accuracy work, for example the {sup 147}Nd from neutron reactions on plutonium. An upgrade to the ENDF library, for ENDF/B-VII.1, based on these and other data, is described in a companion paper to this work.

Selby, H.D., E-mail: hds@lanl.go [Los Alamos National Laboratory, Los Alamos, NM 87545 (United States); Mac Innes, M.R.; Barr, D.W.; Keksis, A.L.; Meade, R.A.; Burns, C.J.; Chadwick, M.B.; Wallstrom, T.C. [Los Alamos National Laboratory, Los Alamos, NM 87545 (United States)

2010-12-15T23:59:59.000Z

160

Crystallization Behavior of Virgin TR-55 Silicone Rubber Measured Using Dynamic Mechanical Thermal Analysis with Liquid Nitrogen Cooling  

SciTech Connect (OSTI)

Dynamic mechanical thermal analysis (DMTA) of virgin TR-55 silicone rubber specimens was conducted. Two dynamic temperature sweep tests, 25 to -100 C and 25 to -70 to 0 C (ramp rate = 1 C/min), were conducted at a frequency of 6.28 rad/s (1 Hz) using a torsion rectangular test geometry. A strain of 0.1% was used, which was near the upper limit of the linear viscoelastic region of the material based on an initial dynamic strain sweep test. Storage (G{prime}) and loss (G{double_prime}) moduli, the ratio G{double_prime}/G{prime} (tan {delta}), and the coefficient of linear thermal expansion ({alpha}) were determined as a function of temperature. Crystallization occurred between -40 and -60 C, with G{prime} increasing from {approx}6 x 10{sup 6} to {approx}4 x 10{sup 8} Pa. The value of {alpha} was fairly constant before ({approx}4 x 10{sup -4} mm/mm- C) and after ({approx}3 x 10{sup -4} mm/mm- C) the transition, and peaked during the transition ({approx}3 x 10{sup -3} mm/mm- C). Melting occurred around -30 C upon heating.

Small IV, W; Wilson, T S

2010-02-11T23:59:59.000Z

Note: This page contains sample records for the topic "measuring thermal evolution" 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

Measurement of thermally induced vibrations of microelectronic devices by use of a heterodyne electronic speckle pattern interferometry imaging technique  

Science Journals Connector (OSTI)

An imaging technique to measure modulated surface displacements on microelectronic devices is presented. A device is supplied by a sinusoidal current that creates a modulated variation...

Grauby, Stphane; Dilhaire, Stefan; Jorez, Sbastien; Lopez, Luis David Patino; Rampnoux, Jean-Michel; Claeys, Wilfrid

2003-01-01T23:59:59.000Z

162

Silicon nucleation and film evolution on silicon dioxide using disilane: Rapid thermal chemical vapor deposition of very smooth silicon at high deposition rates  

SciTech Connect (OSTI)

An investigation of Si{sub 2}H{sub 6} and H{sub 2} for rapid thermal chemical vapor deposition (RTCVD) of silicon on SiO{sub 2} has been performed at temperatures ranging from 590 to 900 C and pressures ranging from 0.1 to 1.5 Torr. Deposition at 590 C yields amorphous silicon films with the corresponding ultrasmooth surface with a deposition rate of 68 nm/min. Cross-sectional transmission electron microscopy of a sample deposited at 625 C and 1 Torr reveals a bilayer structure which is amorphous at the growth surface and crystallized at the oxide interface. Higher temperatures yield polycrystalline films where the surface roughness depends strongly on both deposition pressure and temperature. Silane-based amorphous silicon deposition in conventional systems yields the expected ultrasmooth surfaces, but at greatly reduced deposition rates unsuitable for single-wafer processing. However, disilane, over the process window considered here, yields growth rates high enough to be appropriate for single-wafer manufacturing, thus providing a viable means for deposition of very smooth silicon films on SiO{sub 2} in a single-wafer environment.

Violette, K.E.; Oeztuerk, M.C.; Christensen, K.N.; Maher, D.M. [North Carolina State Univ., Raleigh, NC (United States)

1996-02-01T23:59:59.000Z

163

Development of a compact thermal lithium atom beam source for measurements of electron velocity distribution function anisotropy in electron cyclotron resonance plasmas  

SciTech Connect (OSTI)

The anisotropy of the electron velocity distribution function (EVDF) in plasmas can be deduced from the polarization of emissions induced by anisotropic electron-impact excitation. In this paper, we develop a compact thermal lithium atom beam source for spatially resolved measurements of the EVDF anisotropy in electron cyclotron resonance (ECR) plasmas. The beam system is designed such that the ejected beam has a slab shape, and the beam direction is variable. The divergence and flux of the beam are evaluated by experiments and calculations. The developed beam system is installed in an ECR plasma device with a cusp magnetic field, and the LiI 2s2p emission (670.8 nm) is observed in low-pressure helium plasma. The two-dimensional distributions of the degree and direction of the polarization in the LiI emission are measured by a polarization imaging system. The evaluated polarization distribution suggests the spatial variation of the EVDF anisotropy.

Nishioka, T.; Shikama, T.; Nagamizo, S.; Fujii, K.; Hasuo, M. [Department of Mechanical Engineering and Science, Graduate School of Engineering, Kyoto University, Kyoto 615-8540 (Japan)] [Department of Mechanical Engineering and Science, Graduate School of Engineering, Kyoto University, Kyoto 615-8540 (Japan); Zushi, H. [Research Institute for Applied Mechanics, Kyushu University, Fukuoka 816-8580 (Japan)] [Research Institute for Applied Mechanics, Kyushu University, Fukuoka 816-8580 (Japan); Uchida, M.; Tanaka, H.; Maekawa, T. [Department of Fundamental Energy Science, Graduate School of Energy Science, Kyoto University, Kyoto 606-8502 (Japan)] [Department of Fundamental Energy Science, Graduate School of Energy Science, Kyoto University, Kyoto 606-8502 (Japan); Iwamae, A. [Research Center for Development of Far-Infrared Region, Fukui University, Fukui 910-8507 (Japan)] [Research Center for Development of Far-Infrared Region, Fukui University, Fukui 910-8507 (Japan)

2013-07-15T23:59:59.000Z

164

Burial history and thermal evolution of the southern and western Saharan basins: Synthesis and comparison with the eastern and northern Saharan basins  

Science Journals Connector (OSTI)

...the wells without measured T and Ro data. Figure 2 Map of geothermic degrees gamma (in mC), Saharan platform, contoured at 2...georef;2003074875 2003-074875 Economic geology, geology of energy sources Applied geophysics American Association of Petroleum...

M. Makhous; Yu. I. Galushkin

165

Fast scanning heterodyne receiver for the measurement of the time evolution of the electron temperature profile on TFTR  

SciTech Connect (OSTI)

Two fast scanning heterodyne receivers, swept between 75 to 110 GHz and 110 to 170 GHz in 2 msec every 4 msec, were developed to measure the electron cyclotron emission on the horizontal midplane of the Tokamak Fusion Test Reactor (TFTR) plasma. An absolute, in situ calibration technique enables the determination of the profile of the plasma electron temperature from the cyclotron emission intensity. The 4 msec repetition rate of the receiver allowed the resolution of sawtooth fluctuations of temperature, whose period was 10 to 100 msec, in profiles with central temperatures of 1 to 2.5 keV.

Taylor, G.; Efthimion, P.; McCarthy, M.; Arunasalam, V.; Bitzer, R.; Bryer, J.; Cutler, R.; Fredd, E.; Goldman, M.A.; Kaufman, D.

1984-06-01T23:59:59.000Z

166

Measurement of the thermal conductance of the graphene/SiO2 interface Kin Fai Mak, Chun Hung Lui, and Tony F. Heinz  

E-Print Network [OSTI]

, 043112 (2012) Opposite ReD-dependencies of nanofluid (Al2O3) thermal conductivities between heating and cooling modes Appl. Phys. Lett. 101, 083111 (2012) Thermal transport in graphene supported on copper J of thermal transport in this material system2­4 is currently less advanced. The thermal transport properties

Heinz, Tony F.

167

Bacterial evolution.  

Science Journals Connector (OSTI)

...valid one ructure (75), is vital to the future development of microbiology. als a resem...macro- evolution, megaevolution, or quantum evolution (192). Ini- tially, global...Implications for Bacterial Taxonomy If future findings support the above conclusions...

C R Woese

1987-06-01T23:59:59.000Z

168

Measurement of natural radioactivity and radon exhalation rate in fly ash samples from a thermal power plant and estimation of radiation doses  

Science Journals Connector (OSTI)

Fly ash produced by coal-burning in thermal power station has become a subject of world wide interest in recent years because of its diverse uses in construction activities and considerable economic and environmental importance. Fly ash is used in the production of bricks, sheets, cement and also in land filling etc. Indian coals used in thermal power plants are found to have high ash contents, resulting in the production of large amount of fly ash. Coal contains radionuclides including uranium (the source of inert gas radon), Th and K. Thus coal combustion results in enhanced concentration of natural radionuclides 226Ra, 232Th and 40K. Since these radionuclides concentration in fly ash plays an important role in health physics it is important to measure radionuclides concentration in fly ash. In the present work enhanced radioactivity and radon exhalation rate from fly ash samples collected from a thermal power plant of NTPC (National Thermal Power Corporation), Dadri (U.P.) India, have been measured. A high resolution gamma ray spectroscopic system has been used for the measurement of natural radioactivity (226Ra, 232Th and 40K). Gamma spectrometric measurements were carried out at Inter-University Accelerator Centre, New Delhi using a coaxial n-type \\{HPGe\\} detector (EG&G, ORTEC, Oak Ridge, USA). Activity concentration of 226Ra varies from 81.82.2 to 177.310.0Bqkg?1 with an average value of 118.67.4Bqkg?1 and of 232Th from 111.63.2 to 178.53.9Bqkg?1 with an average value of 147.03.4Bqkg?1. 40K activity was found to be below detection limit in some samples while other samples have shown potassium activity to vary from 365.94.8 to 495.96.2Bqkg?1 with an average value of 352.04.5Bqkg?1. Surface radon exhalation rates (EA) and Mass exhalation rates (EM) in these samples were measured by Sealed can technique using LR-115 type II track detectors. EA is found to vary from 80.19.3 to 242.716.3mBqm?2h?1 with an average value 155.512.8mBqm?2h?1, while EM varies from 3.10.4 to 9.30.6mBqkg?1h?1 with an average value of 6.00.5mBqkg?1h?1. Radium equivalent activity (Raeq), related to the external gamma dose and internal dose due to radon and its daughters range from 283.2 to 422.4Bqkg?1 with an average value of 353.9Bqkg?1. The calculated values of external hazard index (Hex) vary from 0.77 to 1.87 with an average value of 1.03. Most of the samples show the value of Raeq close to the allowed upper limit of 370Bqkg?1 and Hex close to unity respectively except in two samples. Annual effective dose varies from 0.15 to 0.23mSvy?1 with an average value 0.19mSvy?1.

Mamta Gupta; Ajay Kumar Mahur; Rati Varshney; R.G. Sonkawade; K.D. Verma; Rajendra Prasad

2013-01-01T23:59:59.000Z

169

Nonlocal probes of thermalization in holographic quenches with spectral methods  

E-Print Network [OSTI]

We describe the application of pseudo-spectral methods to problems of holographic thermal quenches of relevant couplings in strongly coupled gauge theories. We focus on quenches of a fermionic mass term in a strongly coupled N=4 supersymmetric Yang-Mills plasma, and the subsequent equilibration of the system. From the dual gravitational perspective, we study gravitational collapse of a massive scalar field in asymptotically anti-de-Sitter geometry with a prescribed boundary condition for its non-normalizable mode. Access to the full background geometry of the gravitational collapse allows for the study of nonlocal probes of the thermalization process. We discuss the evolution of the apparent and the event horizons, the two-point correlation functions of operators of large conformal dimensions, and the evolution of the entanglement entropy of the system. We compare the thermalization process from the viewpoint of local (the one-point) correlation functions and these nonlocal probes, finding that the thermalization time as measured by the probes is length dependent, and can exceed that of the one-point function. We further discuss how the different energy scales of the problem contribute to its thermalization.

Alex Buchel; Robert C. Myers; Anton van Niekerk

2014-10-22T23:59:59.000Z

170

Thermal Energy Measurement with Tangential Paddlewheel Flow Meters: Summary of Experimental Results and in-situ Diagnostics  

E-Print Network [OSTI]

paddlewheel flow meters, and several new methods for in-situ diagnostic measures for ascertaining whether or not a flow meter is experiencing fluctuating flow conditions or if a flow meter is suffering a degraded signal due to shaft wear. INTRODUCTION Flow... section where it passes across the candidate sensor that is placed in the inter-changeable test section, through the orifice plate and finally into the is combined with Btu meter the threshold can be much higher than the published threshold of the flow...

Haberl, J. S.; Watt, J. B.

1994-01-01T23:59:59.000Z

171

Measurement of the Anisotropic Thermal Conductivity of Molybdenum Disulfide Single Crystal by the Time-resolved Magneto-optic Kerr Effect  

E-Print Network [OSTI]

with perpendicular magnetization serves as the heater and thermometer in the experiment. The low thermal conductivity for determining the thermal conductivity of materials but the sensitivity of TDTR to the lateral or in-plane thermal conductivity of a sample is low when conventional choices are made for laser spot sizes, #12

Cahill, David G.

172

Measurement  

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

localization that limits the present measurements. The knowledge thus gained will have input not only to fusion research, but to may ques- tions of basic plasma physics....

173

Measurement  

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

in the Department of Physics & Astronomy. Chapel Hill 2005 Approved: A. E. Champagne, Advisor J. C. Blackmon, Reader C. Iliadis, Reader ABSTRACT Ryan P. Fitzgerald: Measurement of...

174

Preliminary requirements for thermal storage subsystems in solar thermal applications  

SciTech Connect (OSTI)

Methodologies for the analysis of value and comparing thermal storage concepts are presented. Value is a measure of worth and is determined by the cost of conventional fuel systems. Value data for thermal storage in large solar thermal electric power applications are presented. Thermal storage concepts must be compared when all are performing the same mission. A method for doing that analysis, called the ranking index, is derived. Necessary data to use the methodology are included.

Copeland, R.J.

1980-04-01T23:59:59.000Z

175

Thermal Dosimetry and Temperature Measurements  

Science Journals Connector (OSTI)

...CCD camera (Cascade:512F, Photometrics, Tucson, AZ). The microscope is composed of (a) 455-nm blue light-emitting diode (Luxeon LXHL-MRRC, Lumileds Lighting, San Jose, CA), (b) exciter filter (455/70, Chroma Technology...

D. A. Christensen

1979-06-01T23:59:59.000Z

176

Thermal Dosimetry and Temperature Measurements  

Science Journals Connector (OSTI)

...N-acetyl-dihydrosphingosine; DAG, diacylglycerol; DETAPAC, diethylenetriamine pentaacetic acid; LED, light-emitting diode; LSM, low-serum medium; LY-R, L5178Y-R; PDT, photodynamic treatment; SAPK, stress-activated protein...

D. A. Christensen

1979-06-01T23:59:59.000Z

177

Mechanical AGN feedback: controlling the thermodynamical evolution of elliptical galaxies  

Science Journals Connector (OSTI)

......to the galactic core often overheat the central ISM, an effect...always maintains an acceptable thermal structure (Kim Fabbiano 2003...are able to regulate the thermal evolution of the ISM, suppressing...being linearly stable against thermal instability (e.g. Balbus......

M. Gaspari; F. Brighenti; P. Temi

2012-07-21T23:59:59.000Z

178

LoCuSS: A COMPARISON OF CLUSTER MASS MEASUREMENTS FROM XMM-NEWTON AND SUBARU-TESTING DEVIATION FROM HYDROSTATIC EQUILIBRIUM AND NON-THERMAL PRESSURE SUPPORT  

SciTech Connect (OSTI)

We compare X-ray hydrostatic and weak-lensing mass estimates for a sample of 12 clusters that have been observed with both XMM-Newton and Subaru. At an over-density of DELTA = 500, we obtain 1 - M {sup X}/M {sup WL} = 0.01 +- 0.07 for the whole sample. We also divided the sample into undisturbed and disturbed sub-samples based on quantitative X-ray morphologies using asymmetry and fluctuation parameters, obtaining 1 - M {sup X}/M {sup WL} = 0.09 +- 0.06 and -0.06 +- 0.12 for the undisturbed and disturbed clusters, respectively. In addition to non-thermal pressure support, there may be a competing effect associated with adiabatic compression and/or shock heating which leads to overestimate of X-ray hydrostatic masses for disturbed clusters, for example, in the famous merging cluster A1914. Despite the modest statistical significance of the mass discrepancy, on average, in the undisturbed clusters, we detect a clear trend of improving agreement between M {sup X} and M {sup WL} as a function of increasing over-density, M{sup X}/M{sup WL}=(0.908+-0.004)+(0.187+-0.010){center_dot} log{sub 10}(DELTA/500). We also examine the gas mass fractions, f{sub gas} = M {sup gas}/M {sup WL}, finding that they are an increasing function of cluster radius, with no dependence on dynamical state, in agreement with predictions from numerical simulations. Overall, our results demonstrate that XMM-Newton and Subaru are a powerful combination for calibrating systematic uncertainties in cluster mass measurements.

Zhang, Yu-Ying [Argelander-Institut fuer Astronomie, Universitaet Bonn, Auf dem Huegel 71, 53121 Bonn (Germany); Okabe, Nobuhiro [Academia Sinica Institute of Astronomy and Astrophysics, P.O. Box 23-141, 10617 Taipei, Taiwan (China); Finoguenov, Alexis [Max-Planck-Institut fuer extraterrestrische Physik, Giessenbachstrasse, 85748 Garching (Germany); Smith, Graham P.; Sanderson, Alastair J. R. [School of Physics and Astronomy, University of Birmingham, Edgbaston, Birmingham, B152TT (United Kingdom); Piffaretti, Rocco [CEA, CEA-Saclay, 91191 Gif-sur-Yvette Cedex (France); Valdarnini, Riccardo [SISSA/ISAS, via Beirut 4, 34014 Trieste (Italy); Babul, Arif [Department of Physics and Astronomy, University of Victoria, 3800 Finnerty Road, Victoria, BC (Canada); Evrard, August E. [Department of Physics and Michigan Center for Theoretical Physics, University of Michigan, Ann Arbor, MI 48109 (United States); Mazzotta, Pasquale [Dipartimento di Fisica, Universita di Roma 'Tor Vergata', Via della Ricerca Scientifica 1, I-00133 Rome (Italy); Marrone, Daniel P., E-mail: yyzhang@astro.uni-bonn.d [Kavli Institute for Cosmological Physics, Department of Astronomy and Astrophysics, University of Chicago, Chicago, IL 60637 (United States)

2010-03-10T23:59:59.000Z

179

Thermalization of isolated quantum systems  

E-Print Network [OSTI]

Understanding the evolution towards thermal equilibrium of an isolated quantum system is at the foundation of statistical mechanics and a subject of interest in such diverse areas as cold atom physics or the quantum mechanics of black holes. Since a pure state can never evolve into a thermal density matrix, the Eigenstate Thermalization Hypothesis (ETH) has been put forward by Deutsch and Srednicki as a way to explain this apparent thermalization, similarly to what the ergodic theorem does in classical mechanics. In this paper this hypothesis is tested numerically. First, it is observed that thermalization happens in a subspace of states (the Krylov subspace) with dimension much smaller than that of the total Hilbert space. We check numerically the validity of ETH in such a subspace, for a system of hard core bosons on a two-dimensional lattice. We then discuss how well the eigenstates of the Hamiltonian projected on the Krylov subspace represent the true eigenstates. This discussion is aided by bringing the projected Hamiltonian to the tridiagonal form and interpreting it as an Anderson localization problem for a finite one-dimensional chain. We also consider thermalization of a subsystem and argue that generation of a large entanglement entropy can lead to a thermal density matrix for the subsystem well before the whole system thermalizes. Finally, we comment on possible implications of ETH in quantum gravity.

Sergei Khlebnikov; Martin Kruczenski

2014-03-12T23:59:59.000Z

180

Thermal Decomposition Mechanism of Disilane  

Science Journals Connector (OSTI)

Thermal Decomposition Mechanism of Disilane ... Thermal decomposition of disilane was investigated using time-of-flight (TOF) mass spectrometry coupled with vacuum ultraviolet single-photon ionization (VUV-SPI) at a temperature range of 675?740 K and total pressure of 20?40 Torr. ... Concentrations of disilane and trisilane during thermal decomposition of disilane were quantitatively measured using the VUV-SPI method. ...

Kazumasa Yoshida; Keiji Matsumoto; Tatsuo Oguchi; Kenichi Tonokura; Mitsuo Koshi

2006-03-18T23:59:59.000Z

Note: This page contains sample records for the topic "measuring thermal evolution" 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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181

Investigation and Analysis of Winter Classroom Thermal Environment in Chongqing  

E-Print Network [OSTI]

the thermal sense value of the occupants, the winter classroom thermal environment was evaluated. Measures for improving the classroom indoor thermal environmental quality were also given. The lower limit air temperature of the non-air conditioned classrooms...

Liu, J.; Li, B.; Yao, R.

2006-01-01T23:59:59.000Z

182

1 000 000 "C/s thin film electrical heater: ln situ resistivity measurements of Al and Ti/Si thin films during ultra rapid thermal annealing  

E-Print Network [OSTI]

introduce a new technique for rapidly heating (10' "C/s) thin films using an electrical thermal annealing- ently, most commercial RTA systems use radiation-heating techniques via tungsten-halogen lamps. These systems typi- cally have a maximum heating rate of 100-300 "C/s. We introduce an alternative methodfor

Allen, Leslie H.

183

Thermal treatment  

Science Journals Connector (OSTI)

Thermal treatment can be regarded as either a pre-treatment of waste prior to final disposal, or as a means of valorising waste by recovering energy. It includes both the burning of mixed MSW in municipal inciner...

Dr. P. White; Dr. M. Franke; P. Hindle

1995-01-01T23:59:59.000Z

184

Thermal Processes  

Broader source: Energy.gov [DOE]

Some thermal processes use the energy in various resources, such as natural gas, coal, or biomass, to release hydrogen, which is part of their molecular structure. In other processes, heat, in...

185

Skin Evolution  

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

Skin Evolution Skin Evolution Name: Olga Location: N/A Country: N/A Date: N/A Question: Do you think it is possible that our ancestors were actually black, and that a gene mutation for an enzyme in the metabollic pathway of melanin meant that not enough melanin was produced some of us ended up with white skin. Primitive apes have black skin, and we evolved from them, so doesn't this mean that humans orginally had black skin??? Replies: Most likely, yes, humans probably evolved from dark-skinned ancestors. I will take issue, however, with your statement that "primitive apes have black skin;" we can't say that for absolute certain, because we have no primitive apes to compare to. All we have now are modern apes. All modern apes - homo sapiens, pan troglodytes, gorilla gorilla - are highly, probably equally, evolved. (One could make an argument that homo sapiens is in many ways more generalized - note the generalized dentition, fragile skeleton, etc. - than other modern apes, and thus could be said to be more primitive.) As far as that goes, the only modern apes with white skin I know of are a color variant of homo sapiens.

186

PCM energy storage during defective thermal cycling:.  

E-Print Network [OSTI]

??Incomplete thermal cycling affects storage capacities of phase change materials (PCMs). Existing PCM measuring methods are presented with their drawbacks. A new device named the (more)

Koekenbier, S.F.

2011-01-01T23:59:59.000Z

187

Electron density measurements of atmospheric-pressure non-thermal N2 plasma jet by Stark broadening and irradiance intensity methods  

Science Journals Connector (OSTI)

An atmospheric-pressure non-thermal plasma jet excited by high frequency alternating current using nitrogen is developed and the electron density in the active region of this plasma jet is investigated by two different methods using optical emission spectroscopy Stark broadening and irradiance intensity method. The irradiance intensity method shows that the average electron density is about 1020/m3 which is slightly smaller than that by the Stark broadening method. However the trend of the change in the electron density with input power obtained by these two methods is consistent.

2014-01-01T23:59:59.000Z

188

High-resolution measurements of the spatial and temporal evolution of megagauss magnetic fields created in intense short-pulse laser-plasma interactions  

SciTech Connect (OSTI)

A pump-probe polarimetric technique is demonstrated, which provides a complete, temporally and spatially resolved mapping of the megagauss magnetic fields generated in intense short-pulse laser-plasma interactions. A normally incident time-delayed probe pulse reflected from its critical surface undergoes a change in its ellipticity according to the magneto-optic Cotton-Mouton effect due to the azimuthal nature of the ambient self-generated megagauss magnetic fields. The temporal resolution of the magnetic field mapping is typically of the order of the pulsewidth, limited by the laser intensity contrast, whereas a spatial resolution of a few ?m is achieved by this optical technique. High-harmonics of the probe can be employed to penetrate deeper into the plasma to even near-solid densities. The spatial and temporal evolution of the megagauss magnetic fields at the target front as well as at the target rear are presented. The ?m-scale resolution of the magnetic field mapping provides valuable information on the filamentary instabilities at the target front, whereas probing the target rear mirrors the highly complex fast electron transport in intense laser-plasma interactions.

Chatterjee, Gourab, E-mail: gourab@tifr.res.in; Singh, Prashant Kumar; Adak, Amitava; Lad, Amit D.; Kumar, G. Ravindra, E-mail: grk@tifr.res.in [Tata Institute of Fundamental Research, 1 Homi Bhabha Road, Mumbai 400 005 (India)

2014-01-15T23:59:59.000Z

189

Thermal Storage and Advanced Heat Transfer Fluids (Fact Sheet)  

SciTech Connect (OSTI)

Fact sheet describing NREL CSP Program capabilities in the area of thermal storage and advanced heat transfer fluids: measuring thermophysical properties, measuring fluid flow and heat transfer, and simulating flow of thermal energy and fluid.

Not Available

2010-08-01T23:59:59.000Z

190

AQUIFER THERMAL ENERGY STORAGE  

E-Print Network [OSTI]

using aquifers for thermal energy storage. Problems outlinedmatical Modeling of Thermal Energy Storage in Aquifers,"ings of Aquifer Thermal Energy Storage Workshop, Lawrence

Tsang, C.-F.

2011-01-01T23:59:59.000Z

191

Measuring the Impact of Experimental Parameters upon the Estimated Thermal Conductivity of Closed-Cell Foam Insulation Subjected to an Accelerated Aging Protocol ? Two Year Results  

SciTech Connect (OSTI)

The thermal conductivity of many closed-cell foam insulation products changes over time as production gases diffuse out of the cell matrix and atmospheric gases diffuse into the cells. Thin slicing has been shown to be an effective means of accelerating this process in such a way as to produce meaningful results. Efforts to produce a more prescriptive version of the ASTM C 1303 standard test method have led to a broad ruggedness test. This test includes the aging of full size insulation specimens for time periods up to five years for later comparison to the predicted results. Experimental parameters under investigation include: slice thickness, slice origin (at the surface or from the core of the slab), thin slice stack composition, product facings, original product thickness, product density, and product type. This paper will compare the results after two years of full-thickness aging.

Stovall, Therese K [ORNL] [ORNL

2009-01-01T23:59:59.000Z

192

Measuring the Impact of Experimental Parameters upon the Estimated Thermal Conductivity of Closed-Cell Foam Insulation Subjected to an Accelerated Aging Protocol  

SciTech Connect (OSTI)

The thermal conductivity of many closed-cell foam insulation products changes over time as production gases diffuse out of the cell matrix and atmospheric gases diffuse into the cells. Thin slicing has been shown to be an effective means of accelerating this process in such a way as to produce meaningful results. Recent efforts to produce a more prescriptive version of the ASTM standard test method have led to the initiation of a broad ruggedness test. This test includes the aging of full size insulation specimens for time periods up to five years for later comparison to the predicted results. Experimental parameters under investigation include: slice thickness, slice origin (at the surface or from the core of the slab), thin slice stack composition, product facings, original product thickness, product density, and product type. This paper will cover the structure of the ruggedness test and provide a glimpse of some early trends

Stovall, Therese K [ORNL] [ORNL; Bogdan, mary [Honeywell, Inc.] [Honeywell, Inc.

2008-01-01T23:59:59.000Z

193

Thermal Analysis of Novel Underfill Materials with Optimum Processing Characteristics  

E-Print Network [OSTI]

Thermal Analysis of Novel Underfill Materials with Optimum Processing Characteristics Yang Liu,1 Yi evolution. Boron nitride, silica-coated alu- minum nitride, and alumina ceramic powders were used as fillers poly- merization. The effects of the filler type and composition on the thermal and mechanical

Harmon, Julie P.

194

Defect Structure and Evolution in Silicon Carbide Irradiated to 1 dpa-SiC at 1100 C  

SciTech Connect (OSTI)

Transmission electron microscopy (TEM), swelling measurements, isochronal annealing, and thermal diffusivity testing were used to characterize the effects of radiation damage in SiC. Together, these techniques provided a comprehensive set of tools for observing and characterizing the structure and evolution of radiation-induced defects in SiC as a function of irradiation temperature and dose. In this study, two types of dense, crystalline, monolithic SiC were subjected to irradiation doses up to 1 dpa-SiC at a temperature of 1100 C, as well as post-irradiation annealing up to 1500 C. The microscopic defect structures observed by TEM were correlated to changes in the macroscopic dimensions, thermal diffusivity and thermal conductivity. The results demonstrated the value of using ultrapure {beta}SiC as an effective reference material to characterize the nature of expected radiation damage in other, more complex, SiC-based materials such as SiC/SiC composites.

D.J. Senor; G.E. Youngblood; L.R. Greenwood; D.V. Archer; D.L. Alexander; M.C. Chen; G.A. Newsome

2002-05-13T23:59:59.000Z

195

Thermally driven asymmetric responses of grains versus spin-glass related distributions of blocking temperature in exchange biased Co/IrMn bilayers  

SciTech Connect (OSTI)

Controlling ferromagnetic/antiferromagnetic blocking temperatures in exchange biased based devices appears crucial for applications. The blocking temperature is ascribed to the ability of both antiferromagnetic grains and interfacial spin-glass-like phases to withstand ferromagnetic magnetization reversal. To better understand the respective contributions of grains versus spin-glass, blocking temperature distributions were measured after various thermal treatments for cobalt/iridium-manganese bilayers. The high-temperature contribution linked to antiferromagnetic grains shifts towards lower temperatures above a threshold thermal annealing. In contrast, the occurrence and evolution of training effects for the low-temperature contribution only agree with its inferred interfacial spin-glass-like origin.

Baltz, V. [SPINTEC, UMR 8191 CNRS/INAC-CEA/UJF-Grenoble 1/Grenoble-INP, F-38054 Cedex (France)] [SPINTEC, UMR 8191 CNRS/INAC-CEA/UJF-Grenoble 1/Grenoble-INP, F-38054 Cedex (France)

2013-02-11T23:59:59.000Z

196

Thermal Desorption of Water-Ice in the Interstellar Medium  

E-Print Network [OSTI]

Water (H2O) ice is an important solid constituent of many astrophysical environments. To comprehend the role of such ices in the chemistry and evolution of dense molecular clouds and comets, it is necessary to understand the freeze-out, potential surface reactivity, and desorption mechanisms of such molecular systems. Consequently, there is a real need from within the astronomical modelling community for accurate empirical molecular data pertaining to these processes. Here we give the first results of a laboratory programme to provide such data. Measurements of the thermal desorption of H2O ice, under interstellar conditions, are presented. For ice deposited under conditions that realistically mimic those in a dense molecular cloud, the thermal desorption of thin films (~50 molecular layers) is found to occur with zero order kinetics characterised by a surface binding energy, E_{des}, of 5773 +/- 60 K, and a pre-exponential factor, A, of 10^(30 +/- 2) molecules cm^-2 s^-1. These results imply that, in the dense interstellar medium, thermal desorption of H2O ice will occur at significantly higher temperatures than has previously been assumed.

Helen J. Fraser; Mark P. Collings; Martin R. S. McCoustra; David A. Williams

2001-07-25T23:59:59.000Z

197

Measurement of the energy, multiplicity and angular correlation of ?-rays from the thermal neutron capture reaction Gd(n, ?) using JPARC-ANNRI  

SciTech Connect (OSTI)

We conducted an experiment using the JPARC-ANNRI spectrometer to measure the energy, multiplicity and correlation of ?-rays from the neutron capture of natural gadolinium. We incorporated the GEANT4 Monte Carlo (MC) simulation into the detector, and compared the data with the results of the MC simulation. We report our data analysis and compare our data with those obtained by the MC simulation.

Ou, Iwa; Yamada, Yoshiyuki; Yano, Takatomi; Mori, Takaaki; Kayano, Tsubasa; Sakuda, Makoto [Department of Physics, Okayama University, Okayama, 700-8530 (Japan); Kimura, Atsushi; Harada, Hideo [Japan Atomic Energy Agency, 2-4 Shirakata Shirane, Tokai, Naka, Ibaraki 319-1195 (Japan)

2014-05-02T23:59:59.000Z

198

Modified Thermal-Optical Analysis Using Spectral Absorption Selectivity to  

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

Modified Thermal-Optical Analysis Using Spectral Absorption Selectivity to Modified Thermal-Optical Analysis Using Spectral Absorption Selectivity to Distinguish Black Carbon from Pyrolized Organic Carbon Title Modified Thermal-Optical Analysis Using Spectral Absorption Selectivity to Distinguish Black Carbon from Pyrolized Organic Carbon Publication Type Journal Article Year of Publication 2008 Authors Hadley, Odelle L., Craig E. Corrigan, and Thomas W. Kirchstetter Journal Environmental Science and Technology Volume 42 Pagination 8459-8464 Abstract This study presents a method for analyzing the black carbon (BC) mass loading on a quartz fiber filter using a modified thermal-optical analysis method, wherein light transmitted through the sample is measured over a spectral region instead of at a single wavelength. Evolution of the spectral light transmission signal depends on the relative amounts of light-absorbing BC and char, the latter of which forms when organic carbon in the sample pyrolyzes during heating. Absorption selectivities of BC and char are found to be distinct and are used to apportion the amount of light attenuated by each component in the sample. Light attenuation is converted to mass concentration on the basis of derived mass attenuation efficiencies (MAEs) of BC and char. The fractions of attenuation due to each component are scaled by their individual MAE values and added together as the total mass of light absorbing carbon (LAC). An iterative algorithm is used to find the MAE values for both BC and char that provide the best fit to the carbon mass remaining on the filter (derived from direct measurements of thermally evolved CO2) at temperatures higher than 480 degrees C. This method was applied to measure the BC concentration in precipitation samples collected in northern California. The uncertainty in the measured BC concentration of samples that contained a high concentration of organics susceptible to char ranged from 12% to 100%, depending on the mass loading of BC on the filter. The lower detection limit for this method was approximately 0.35 microg of BC, and the uncertainty approached 20% for BC mass loading greater than 1.0 microg of BC.

199

Seasonal thermal energy storage  

SciTech Connect (OSTI)

This report describes the following: (1) the US Department of Energy Seasonal Thermal Energy Storage Program, (2) aquifer thermal energy storage technology, (3) alternative STES technology, (4) foreign studies in seasonal thermal energy storage, and (5) economic assessment.

Allen, R.D.; Kannberg, L.D.; Raymond, J.R.

1984-05-01T23:59:59.000Z

200

Why Granular Media Are, After All, Thermal  

E-Print Network [OSTI]

Granular media are considered "athermal", because the grains are too large to display Brownian type thermal fluctuations. Yet being macroscopic, every grain undergoes thermal expansion, possesses a temperature that may be measured with a thermometer, and consists of many, many internal degrees of freedom that in their sum do affect granular dynamics. Therefore, including them in a comprehensive approach to account for granular behavior entails crucial advantages. The pros and cons of thermal versus athermal descriptions are considered.

Yimin Jiang; Mario Liu

2014-07-27T23:59:59.000Z

Note: This page contains sample records for the topic "measuring thermal evolution" 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

Evolution of Web Systems  

Science Journals Connector (OSTI)

The World Wide Web has led to a new kind of software, web systems, which are based on web technologies. Just like software in other domains, web systems have evolution challenges. This chapter discusses evolution...

Holger M. Kienle; Damiano Distante

2014-01-01T23:59:59.000Z

202

Thermal unobtainiums? The perfect thermal conductor and  

E-Print Network [OSTI]

contribute to thermal resistance · Isotopically pure diamond has highest thermal conductivity of any material materials: disordered layered crystals Conclude with some thoughts on promising, high-risk, research even in a computer model. #12;Thermal resistance is created by Umklapp scattering (U

Braun, Paul

203

Radio Source Evolution on Galactic Scales  

E-Print Network [OSTI]

profile external atmosphere. Key words: galaxies: jets radiation mechanisms: non-thermal galaxies: active 1 INTRODUCTION Understanding the detailed evolution of radio-loud jets and co- coons as they propagate through the intragalactic and intracluster... shocks the IGM/ICM at the hotspot, and once the jet material becomes under-dense, a backflow of material at the hotspot inflates enormous cocoons filled with a plasma of particles and magnetic fields. The jet pushes forward and the co- coon expands...

Maciel, T.; Alexander, P.

2014-01-01T23:59:59.000Z

204

Influence of embedded-carbon nanotubes on the thermal properties of copper matrix nanocomposites processed  

E-Print Network [OSTI]

-level mix- ing, exhibits CNTs homogeneously dispersed in the Cu matrix. Measured thermal conductivity: Metal matrix composites; Nanocomposite; Carbon and graphite; Thermal conductivity Carbon nanotubes (CNTs management applications, due to their extraordinarily low coefficient of thermal expan- sion (CTE) [1

Hong, Soon Hyung

205

Determination of thermal conductivity and formation temperature from cooling history of friction-heated probes  

Science Journals Connector (OSTI)

......of geothermal gradient and thermal conductivity of rocks or sediments...the formation temperature and thermal conductivity. Ideally, to...measurements require extra battery power supply and an additional...cooling curve for deducing the thermal properties has been contemplated......

Tien-Chang Lee; A. D. Duchkov; S. G. Morozov

2003-02-01T23:59:59.000Z

206

Thermal Control & System Integration  

Broader source: Energy.gov [DOE]

The thermal control and system integration activity focuses on issues such as the integration of motor and power control technologies and the development of advanced thermal control technologies....

207

Evolution of fields in a second order phase transition  

Science Journals Connector (OSTI)

We analyze the evolution of scalar and gauge fields during a second order phase transition using a Langevin equation approach. We show that topological defects formed during the phase transition are stable to thermal fluctuations. Our method allows the field evolution to be followed throughout the phase transition, for both expanding and nonexpanding universes. The results verify the Kibble mechanism for defect formation during phase transitions.

Adrian Martin and Anne-Christine Davis

1995-09-15T23:59:59.000Z

208

Chemical preconcentrator with integral thermal flow sensor  

DOE Patents [OSTI]

A chemical preconcentrator with integral thermal flow sensor can be used to accurately measure fluid flow rate in a microanalytical system. The thermal flow sensor can be operated in either constant temperature or constant power mode and variants thereof. The chemical preconcentrator with integral thermal flow sensor can be fabricated with the same MEMS technology as the rest of the microanlaytical system. Because of its low heat capacity, low-loss, and small size, the chemical preconcentrator with integral thermal flow sensor is fast and efficient enough to be used in battery-powered, portable microanalytical systems.

Manginell, Ronald P. (Albuquerque, NM); Frye-Mason, Gregory C. (Cedar Crest, NM)

2003-01-01T23:59:59.000Z

209

Nanoscale thermal transport. II. 20032012  

SciTech Connect (OSTI)

A diverse spectrum of technology drivers such as improved thermal barriers, higher efficiency thermoelectric energy conversion, phase-change memory, heat-assisted magnetic recording, thermal management of nanoscale electronics, and nanoparticles for thermal medical therapies are motivating studies of the applied physics of thermal transport at the nanoscale. This review emphasizes developments in experiment, theory, and computation in the past ten years and summarizes the present status of the field. Interfaces become increasingly important on small length scales. Research during the past decade has extended studies of interfaces between simple metals and inorganic crystals to interfaces with molecular materials and liquids with systematic control of interface chemistry and physics. At separations on the order of ?1?nm, the science of radiative transport through nanoscale gaps overlaps with thermal conduction by the coupling of electronic and vibrational excitations across weakly bonded or rough interfaces between materials. Major advances in the physics of phonons include first principles calculation of the phonon lifetimes of simple crystals and application of the predicted scattering rates in parameter-free calculations of the thermal conductivity. Progress in the control of thermal transport at the nanoscale is critical to continued advances in the density of information that can be stored in phase change memory devices and new generations of magnetic storage that will use highly localized heat sources to reduce the coercivity of magnetic media. Ultralow thermal conductivitythermal conductivity below the conventionally predicted minimum thermal conductivityhas been observed in nanolaminates and disordered crystals with strong anisotropy. Advances in metrology by time-domain thermoreflectance have made measurements of the thermal conductivity of a thin layer with micron-scale spatial resolution relatively routine. Scanning thermal microscopy and thermal analysis using proximal probes has achieved spatial resolution of 10?nm, temperature precision of 50 mK, sensitivity to heat flows of 10 pW, and the capability for thermal analysis of sub-femtogram samples.

Cahill, David G., E-mail: d-cahill@illinois.edu; Braun, Paul V. [Department of Materials Science and Engineering and the Frederick Seitz Materials Research Laboratory, University of Illinois, Urbana, Illinois 61801 (United States); Chen, Gang [Department of Mechanical Engineering, MIT, Cambridge, Massachusetts 02139 (United States); Clarke, David R. [School of Engineering and Applied Sciences, Harvard University, Cambridge, Massachusetts 02138 (United States); Fan, Shanhui [Department of Electrical Engineering, Stanford University, Stanford, California 94305 (United States); Goodson, Kenneth E. [Department of Mechanical Engineering, Stanford University, Stanford, California 94305 (United States); Keblinski, Pawel [Department of Materials Science and Engineering, Rensselaer Polytechnic Institute, Troy, New York 12180 (United States); King, William P. [Department of Mechanical Sciences and Engineering, University of Illinois, Urbana, Illinois 61801 (United States); Mahan, Gerald D. [Department of Physics, Penn State University, University Park, Pennsylvania 16802 (United States); Majumdar, Arun [Department of Mechanical Engineering, University of California, Berkeley, California 94720 (United States); Maris, Humphrey J. [Department of Physics, Brown University, Providence, Rhode Island 02912 (United States); Phillpot, Simon R. [Department of Materials Science and Engineering, University of Florida, Gainseville, Florida 32611 (United States); Pop, Eric [Department of Electrical and Computer Engineering, University of Illinois, Urbana, Illinois 61801 (United States); Shi, Li [Department of Mechanical Engineering, University of Texas, Autin, Texas 78712 (United States)

2014-03-15T23:59:59.000Z

210

Thermal Management of Solar Cells  

E-Print Network [OSTI]

a better thermal conductance and when ceramic particles areor ceramic fillers that enhances thermal conductivity. Solid

Saadah, Mohammed Ahmed

2013-01-01T23:59:59.000Z

211

Geological and thermochronological evolution of the lower crust of southern Africa  

E-Print Network [OSTI]

Geochronological, thermochronological and isotopic studies of kimberlite-borne crustal xenoliths have been used to elucidate the architecture and thermal evolution of the continental lithosphere of southern Africa. U-Pb ...

Schmitz, Mark D. (Mark David), 1972-

2002-01-01T23:59:59.000Z

212

Sandia National Laboratories: Measurements of Thermal Stratification...  

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

and Exhibition (EU PVSC) EC Top Publications Reference Model 5 (RM5): Oscillating Surge Wave Energy Converter Experimental Wave Tank Test for Reference Model 3 Floating- Point...

213

Los Alamos probes mysteries of uranium dioxide's thermal conductivity  

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

of nuclear materials into the hands of terrorists and other non-state actors. The depleted uranium dioxide crystals used for the thermal conductivity measurements were...

214

NREL: Vehicles and Fuels Research - Light-Duty Vehicle Thermal...  

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

and passenger thermal comfort. Analogous to crash-test dummies, these manikins measure heat loss and skin temperature through numerous sensors, making it possible to efficiently...

215

QCD Evolution Workshop: Introduction  

SciTech Connect (OSTI)

The introduction talk given at the beginning of QCD Evolution workshop held in Thomas Jefferson National Accelerator Facility (Jefferson Lab) on May 14 -17, 2012.

Alexey Prokudin

2012-12-01T23:59:59.000Z

216

RESEARCHANDTECHNICALNOTES Thermal contraction of Vespel SP-22 and  

E-Print Network [OSTI]

materials is becoming common in low temperature apparatus. Vespel SP-22 has a thermal conductivity nearly of thermal contraction of such construction materials is often necessary for proper design of low temperature devices. We present here data on the total thermal contraction of these two materials, measured relative

Packard, Richard E.

217

Directed Evolution of Thermus Maltogenic Amylase toward Enhanced Thermal Resistance  

Science Journals Connector (OSTI)

...and T. vulgaris a-amylase II (1JI2) (16...intermediate, which breaks down to yield an a-linked...1995. Oxidation stable amylases for detergents, p...characterization of novel maltogenic amylase that hydrolyzes and transglycosylates...

Young-Wan Kim; Ji-Hye Choi; Jung-Wan Kim; Cheonseok Park; Jung-Woo Kim; Hyunju Cha; Soo-Bok Lee; Byoung-Ha Oh; Tae-Wha Moon; Kwan-Hwa Park

2003-08-01T23:59:59.000Z

218

Thermal Evolution Models for the Valles Caldera with Reference...  

Open Energy Info (EERE)

by commercial interests seeking hydrothermal resources. In addition, a number of test wells have been drilled just outside the calderas west margin by the Los Alamos...

219

Thermal evolution of gene expression profiles in Drosophila subobscura  

Science Journals Connector (OSTI)

Hybridizations and washes were performed using the automatic system Lucidea SlidePro (Amersham, UK). The hybridization was allowed to proceed for 15 h at 25C, and the slides were sequentially washed three tim...

Hafid Laayouni; Francisco Garca-Franco

2007-03-01T23:59:59.000Z

220

Understanding the thermal evolution of deep-water continental margins  

Science Journals Connector (OSTI)

... exploration risks are potentially much higher. The bulk of major hydrocarbon fields located in shallow-water depths (that is, up to 200 m) have probably been located, if one ... Over the past ten years, there has been a relentless drive to explore ever-increasing water depths. This drive has been stimulated by an engineering technology that has allowed us ...

Nicky White; Mark Thompson; Tony Barwise

2003-11-20T23:59:59.000Z

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


221

HEATS: Thermal Energy Storage  

SciTech Connect (OSTI)

HEATS Project: The 15 projects that make up ARPA-Es HEATS program, short for High Energy Advanced Thermal Storage, seek to develop revolutionary, cost-effective ways to store thermal energy. HEATS focuses on 3 specific areas: 1) developing high-temperature solar thermal energy storage capable of cost-effectively delivering electricity around the clock and thermal energy storage for nuclear power plants capable of cost-effectively meeting peak demand, 2) creating synthetic fuel efficiently from sunlight by converting sunlight into heat, and 3) using thermal energy storage to improve the driving range of electric vehicles (EVs) and also enable thermal management of internal combustion engine vehicles.

None

2012-01-01T23:59:59.000Z

222

Holographic thermalization patterns  

E-Print Network [OSTI]

We investigate the behaviour of various correlators in N=4 super Yang Mills theory, taking finite coupling corrections into account. In the thermal limit we investigate the flow of the quasinormal modes as a function of the 't Hooft coupling. Then by using a specific model of holographic thermalization we investigate the deviation of the spectral densities from their thermal limit in an out-of-equilibrium situation. The main focus lies on the thermalization pattern with which the various plasma constituents of different energies approach their final thermal distribution as the coupling constant decreases from the infinite coupling limit. All results point towards the weakening of the usual top down thermalization pattern.

Stefan Stricker

2014-03-11T23:59:59.000Z

223

Holographic thermalization patterns  

E-Print Network [OSTI]

We investigate the behaviour of various correlators in N=4 super Yang Mills theory, taking finite coupling corrections into account. In the thermal limit we investigate the flow of the quasinormal modes as a function of the 't Hooft coupling. Then by using a specific model of holographic thermalization we investigate the deviation of the spectral densities from their thermal limit in an out-of-equilibrium situation. The main focus lies on the thermalization pattern with which the various plasma constituents of different energies approach their final thermal distribution as the coupling constant decreases from the infinite coupling limit. All results point towards the weakening of the usual top down thermalization pattern.

Stricker, Stefan

2014-01-01T23:59:59.000Z

224

Definition: British thermal unit | Open Energy Information  

Open Energy Info (EERE)

thermal unit thermal unit Jump to: navigation, search Dictionary.png British thermal unit The amount of heat required to raise the temperature of one pound of water one degree Fahrenheit; often used as a unit of measure for the energy content of fuels.[1][2] View on Wikipedia Wikipedia Definition The British thermal unit (BTU or Btu) is a traditional unit of energy equal to about 1055 joules. It is the amount of energy needed to cool or heat one pound of water by one degree Fahrenheit. In scientific contexts the BTU has largely been replaced by the SI unit of energy, the joule. The unit is most often used as a measure of power (as BTU/h) in the power, steam generation, heating, and air conditioning industries, and also as a measure of agricultural energy production (BTU/kg). It is still used

225

Experimental and analytical analyses of the thermal conductivities and high-temperature characteristics of silica aerogels based on microstructures  

Science Journals Connector (OSTI)

An analytical heat transfer model based on scanning electron microscopy, BrunauerEmmettTeller and pycnometry measurements and a 3D random diffusion-limited clustercluster aggregation structure is proposed to calculate the temperature-dependent microstructural parameters and thermal conductivities of silica aerogels. This model is a pure prediction model, which does not need experimentally fitted empirical parameters and only needs four measured structural parameters as input parameters. This model can provide high-temperature microstructural and thermophysical properties as well as theoretical guidelines for material designs with optimum parameters. The results show that three stages occur during the thermal evolution processes of the aerogel structure with increasing temperature from 300 to 1500K. The current analytical model is fully validated by experimental data. The constant structure assumptions used in previous heat transfer models are found to cause significant errors at higher temperatures as the temperature-dependent structure deformation significantly increases the aerogel thermal conductivity. The conductive and total thermal conductivities of silica aerogels after high-temperature heat treatments are much larger than those with no heat treatment.

Jun-Jie Zhao; Yuan-Yuan Duan; Xiao-Dong Wang; Bu-Xuan Wang

2013-01-01T23:59:59.000Z

226

Thermal photons as a quark-gluon plasma thermometer revisited  

E-Print Network [OSTI]

Photons are a penetrating probe of the hot medium formed in heavy-ion collisions, but they are emitted from all collision stages. At photon energies below 2-3 GeV, the measured photon spectra are approximately exponential and can be characterized by their inverse logarithmic slope, often called "effective temperature" $T_\\mathrm{eff}$. Modelling the evolution of the radiating medium hydrodynamically, we analyze the factors controlling the value of $T_\\mathrm{eff}$ and how it is related to the evolving true temperature $T$ of the fireball. We find that at RHIC and LHC energies most photons are emitted from fireball regions with $T{\\,\\sim\\,}T_\\mathrm{c}$ near the quark-hadron phase transition, but that their effective temperature is significantly enhanced by strong radial flow. Although a very hot, high pressure early collision stage is required for generating this radial flow, we demonstrate that the experimentally measured large effective photon temperatures $T_\\mathrm{eff}{\\,>\\,}T_\\mathrm{c}$, taken alone, do not prove that any electromagnetic radiation was actually emitted from regions with true temperatures well above $T_\\mathrm{c}$. We explore tools that can help to provide additional evidence for the relative weight of photon emission from the early quark-gluon and late hadronic phases. We find that the recently measured centrality dependence of the total thermal photon yield requires a larger contribution from late emission than presently encoded in our hydrodynamic model.

Chun Shen; Ulrich W. Heinz; Jean-Francois Paquet; Charles Gale

2014-03-28T23:59:59.000Z

227

Utility of transient testing to characterize thermal interface materials  

E-Print Network [OSTI]

This paper analyzes a transient method for the characterization of low-resistance thermal interfaces of microelectronic packages. The transient method can yield additional information about the package not available with traditional static methods at the cost of greater numerical complexity, hardware requirements, and sensitivity to noise. While the method is established for package-level thermal analysis of mounted and assembled parts, its ability to measure the relatively minor thermal impedance of thin thermal interface material (TIM) layers has not yet been fully studied. We combine the transient thermal test with displacement measurements of the bond line thickness to fully characterize the interface.

Smith, B; Michel, B

2008-01-01T23:59:59.000Z

228

Utility of transient testing to characterize thermal interface materials  

E-Print Network [OSTI]

This paper analyzes a transient method for the characterization of low-resistance thermal interfaces of microelectronic packages. The transient method can yield additional information about the package not available with traditional static methods at the cost of greater numerical complexity, hardware requirements, and sensitivity to noise. While the method is established for package-level thermal analysis of mounted and assembled parts, its ability to measure the relatively minor thermal impedance of thin thermal interface material (TIM) layers has not yet been fully studied. We combine the transient thermal test with displacement measurements of the bond line thickness to fully characterize the interface.

B. Smith; T. Brunschwiler; B. Michel

2008-01-07T23:59:59.000Z

229

A coupled THC model of the FEBEX in situ test with bentonite swelling and chemical and thermal osmosis  

SciTech Connect (OSTI)

The performance assessment of a geological repository for radioactive waste requires quantifying the geochemical evolution of the bentonite engineered barrier. This barrier will be exposed to coupled thermal (T), hydrodynamic (H), mechanical (M) and chemical (C) processes. This paper presents a coupled THC model of the FEBEX (Full-scale Engineered Barrier EXperiment) in situ test which accounts for bentonite swelling and chemical and thermal osmosis. Model results attest the relevance of thermal osmosis and bentonite swelling for the geochemical evolution of the bentonite barrier while chemical osmosis is found to be almost irrelevant. The model has been tested with data collected after the dismantling of heater 1 of the in situ test. The model reproduces reasonably well the measured temperature, relative humidity, water content and inferred geochemical data. However, it fails to mimic the solute concentrations at the heater-bentonite and bentonite-granite interfaces because the model does not account for the volume change of bentonite, the CO{sub 2}(g) degassing and the transport of vapor from the bentonite into the granite. The inferred HCO{sub 3}{sup -} and pH data cannot be explained solely by solute transport, calcite dissolution and protonation/deprotonation by surface complexation, suggesting that such data may be affected also by other reactions.

Zheng, L.; Samper, J.; Montenegro, L.

2011-04-01T23:59:59.000Z

230

Non-thermal Plasma Chemistry Non-thermal Thermal  

E-Print Network [OSTI]

automotive industry optics biomedical technology environmental technology Plasma Technology Quote from: Pla-thermal Plasma Chemical Flow Reactor #12;Werner von Siemens ,, ... construction of an apparatus generation (1857) pollution control volatile organic components, NOx reforming, ... radiation sources excimer

Greifswald, Ernst-Moritz-Arndt-Universität

231

Simulating Microstructural Evolution and Electrical Transport in Ceramic Gas Sensors  

E-Print Network [OSTI]

. In this paper, using the example of the thermal processing of ceramic gas sensors, an integrated compu- tationalSimulating Microstructural Evolution and Electrical Transport in Ceramic Gas Sensors Yunzhi Wang in ceramic gas sensors has been proposed. First, the particle-flow model and the continuum-phase-field method

Ciobanu, Cristian

232

A field study for understanding thermally driven coupled processesin partially saturated fractured welded tuff  

SciTech Connect (OSTI)

As part of a multi-laboratory team, we are carrying out two in situ thermal tests--the single Heater Test and Drift Scale Test, in an underground facility at Yucca Mountain, Nevada, USA, the proposed site for a high-level nuclear waste repository. Our objective in these tests is to gain a more in-depth understanding of the coupled thermal-hydrological-mechanical-chemical processes likely to exist in the fractured rock mass around a geological repository. These coupled processes are monitored continuously by numerous sensors emplaced in boreholes, while cross-hole radar tomography, neutron logging, electrical resistivity tomography, and interference air-permeability tests all serve to measure moisture change in the rock mass. Thermal-hydrological processes for both tests have been simulated (using a 3-D numerical model) and compared to the extensive data set. In this paper, we present examples to illustrate how an iterative approach requiring close integration of modeling and measurements enables us to track the complex coupled processes we seek to understand. The main manifestation of coupled thermal-hydrological processes is in the time evolution of the drying and condensation zones. Good agreement exists between model predictions and measurements, specifically the decrease in air-permeability values within zones of increased liquid saturation in the fractures and the increase of radar velocity in cross-hole radar survey in zones of decreased matrix liquid saturation. A heat-pipe signature in the temperature data arising from liquid-vapor counter-flow occurs in both the measurements and simulated results. The good agreement between predictions from the numerical simulations and measurements in the thermal tests indicates that our basic understanding of the thermal-hydrological processes in a potential repository at Yucca Mountain is sound. However, detailed behavior is impacted by site-specific heterogeneity, in the form of discrete fractures that are not likely to be predictable a priori. One emphasis of the on-going Drift Scale Test is to build on the present understanding and to assess the impact of heterogeneity to the repository performance.

Tsang, Yvonne

1998-12-01T23:59:59.000Z

233

Thermal contact resistance  

E-Print Network [OSTI]

This work deals with phenomena of thermal resistance for metallic surfaces in contact. The main concern of the work is to develop reliable and practical methods for prediction of the thermal contact resistance for various ...

Mikic, B. B.

1966-01-01T23:59:59.000Z

234

Solar Thermal Processes  

Science Journals Connector (OSTI)

The use of solar energy for desalination purposes was one of ... The process is based on the use of solar thermal energy to evaporate water, thus separating pure ... brine. In this chapter an overview of solar thermal

M.T. Chaibi; Ali M. El-Nashar

2009-01-01T23:59:59.000Z

235

Thermal Neutron Scattering  

Science Journals Connector (OSTI)

... of its title. It is not for the nuclear physicist, nor even for the neutron physicist, but for the student of solids and liquids. "Thermal ... physicist, but for the student of solids and liquids. "Thermal neutron ...

G. E. BACON

1968-11-09T23:59:59.000Z

236

Density measurements Viscosity measurements  

E-Print Network [OSTI]

Density measurements Viscosity measurements Temperature measurements Pressure measurements Flow rate measurements Velocity measurements Sensors How to measure fluid flow properties ? Am´elie Danlos Ravelet Experimental methods for fluid flows: an introduction #12;Density measurements Viscosity

Ravelet, Florent

237

Time dependent quantum thermodynamics of a coupled quantum oscillator system in a small thermal environment  

SciTech Connect (OSTI)

Simulations are performed of a small quantum system interacting with a quantum environment. The system consists of various initial states of two harmonic oscillators coupled to give normal modes. The environment is designed by its level pattern to have a thermodynamic temperature. A random coupling causes the system and environment to become entangled in the course of time evolution. The approach to a Boltzmann distribution is observed, and effective fitted temperatures close to the designed temperature are obtained. All initial pure states of the system are driven to equilibrium at very similar rates, with quick loss of memory of the initial state. The time evolution of the von Neumann entropy is calculated as a measure of equilibration and of quantum coherence. It is pointed out using spatial density distribution plots that quantum interference is eliminated only with maximal entropy, which corresponds thermally to infinite temperature. Implications of our results for the notion of classicalizing behavior in the approach to thermal equilibrium are briefly considered.

Barnes, George L. [Department of Chemistry and Biochemistry, Siena College, Loudonville, New York 12211 (United States)] [Department of Chemistry and Biochemistry, Siena College, Loudonville, New York 12211 (United States); Kellman, Michael E. [Department of Chemistry and Institute of Theoretical Science, University of Oregon, Eugene, Oregon 97403 (United States)] [Department of Chemistry and Institute of Theoretical Science, University of Oregon, Eugene, Oregon 97403 (United States)

2013-12-07T23:59:59.000Z

238

Models of magnetic field evolution and effective viscosity in weakly collisional extragalactic plasmas  

Science Journals Connector (OSTI)

......evolution of the magnetic field is the thermal stability of the ICM and hence the existence...This means that whatever determines the thermal stability of the ICM in this scenario...Description of Plasma-Galeev A. A., Sudan R. N., eds. (1983) North-Holland......

Federico Mogavero; Alexander A. Schekochihin

2014-01-01T23:59:59.000Z

239

Thermal Performance Benchmarking (Presentation)  

SciTech Connect (OSTI)

This project will benchmark the thermal characteristics of automotive power electronics and electric motor thermal management systems. Recent vehicle systems will be benchmarked to establish baseline metrics, evaluate advantages and disadvantages of different thermal management systems, and identify areas of improvement to advance the state-of-the-art.

Moreno, G.

2014-11-01T23:59:59.000Z

240

Multiwavelength Thermal Emission  

E-Print Network [OSTI]

Multiwavelength Astronomy NASA #12;Thermal Emission #12;Thermal Emission Non-thermal p-p collisions Optical IR Radio/ Microwave sources of emission massive stars, WHIM, Ly many dust, cool objects-ray ~GeV Gamma-ray ~TeV sources of emission AGN, clusters, SNR, binaries, stars AGN (obscured), shocks

California at Santa Cruz, University of

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


241

Improvements of the Variable Thermal Resistance  

E-Print Network [OSTI]

A flat mounting unit with electronically variable thermal resistance [1] has been presented in the last year [2]. The design was based on a Peltier cell and the appropriate control electronics and software. The device is devoted especially to the thermal characterization of packages, e.g. in dual cold plate arrangements. Although this design meets the requirements of the static measurement we are intended to improve its parameters as the settling time and dynamic thermal impedance and the range of realized thermal resistance. The new design applies the heat flux sensor developed by our team as well [3], making easier the control of the device. This development allows even the realization of negative thermal resistances.

V. Szekely; S. Torok; E. Kollar

2008-01-07T23:59:59.000Z

242

Insights From Laboratory Experiments On Simulated Faults With Application To Fracture Evolution In Geothermal Systems  

SciTech Connect (OSTI)

Laboratory experiments provide a wealth of information related to mechanics of fracture initiation, fracture propagation processes, factors influencing fault strength, and spatio-temporal evolution of fracture properties. Much of the existing literature reports on laboratory studies involving a coupling of thermal, hydraulic, mechanical, and/or chemical processes. As these processes operate within subsurface environments exploited for their energy resource, laboratory results provide insights into factors influencing the mechanical and hydraulic properties of geothermal systems. I report on laboratory observations of strength and fluid transport properties during deformation of simulated faults. The results show systematic trends that vary with stress state, deformation rate, thermal conditions, fluid content, and rock composition. When related to geophysical and geologic measurements obtained from engineered geothermal systems (e.g. microseismicity, wellbore studies, tracer analysis), laboratory results provide a means by which the evolving thermal reservoir can be interpreted in terms of physico-chemical processes. For example, estimates of energy release and microearthquake locations from seismic moment tensor analysis can be related to strength variations observed from friction experiments. Such correlations between laboratory and field data allow for better interpretations about the evolving mechanical and fluid transport properties in the geothermal reservoir ultimately leading to improvements in managing the resource.

Stephen L. Karner, Ph.D

2006-06-01T23:59:59.000Z

243

The YNEV stellar evolution and oscillation code  

E-Print Network [OSTI]

We have developed a new stellar evolution and oscillation code YNEV, which calculates the structures and evolutions of stars, taking into account hydrogen and helium burning. A nonlocal turbulent convection theory and an updated overshoot mixing model are optional in this code. The YNEV code can evolve low- and intermediate-mass stars from pre-main sequence (PMS) to thermal pulsing asymptotic branch giant (TP-AGB) or white dwarf. The YNEV oscillation code calculates the eigenfrequencies and eigenfunctions of the adiabatic oscillations of given stellar structure. The input physics and the numerical scheme adopted in the code are introduced in this paper. The examples of solar models, stellar evolutionary tracks of low- and intermediate-mass stars with different convection theory (i.e., mixing-length theory (MLT) and the nonlocal turbulent convection theory), and stellar oscillations are shown.

Zhang, Q S

2014-01-01T23:59:59.000Z

244

Thermal Insulation in Solar Thermal Devices  

Science Journals Connector (OSTI)

Thermal Insulation is a device or a practice which is used in a system for minimising heat losses caused due to transfer of heat from hotter to colder regions. It is one of the cheapest methods of energy conse...

B. C. Raychaudhuri

1986-01-01T23:59:59.000Z

245

Thermal well-test method  

DOE Patents [OSTI]

A well-test method involving injection of hot (or cold) water into a groundwater aquifer, or injecting cold water into a geothermal reservoir is disclosed. By making temperature measurements at various depths in one or more observation wells, certain properties of the aquifer are determined. These properties, not obtainable from conventional well test procedures, include the permeability anisotropy, and layering in the aquifer, and in-situ thermal properties. The temperature measurements at various depths are obtained from thermistors mounted in the observation wells.

Tsang, C.F.; Doughty, C.A.

1984-02-24T23:59:59.000Z

246

Thermal metamorphism in the lesser Himalaya of Nepal determined from Raman spectroscopy of carbonaceous material  

E-Print Network [OSTI]

Thermal metamorphism in the lesser Himalaya of Nepal determined from Raman spectroscopy of central and far-western Nepal, including data from near the MCT zone, where a comparison with conventional on the thermal evolution of the Himalaya in Nepal using the RSCM method. This emblematic geological setting

Avouac, Jean-Philippe

247

Thermal Conductance of Thin Silicon Nanowires  

Science Journals Connector (OSTI)

The thermal conductance of individual single crystalline silicon nanowires with diameters less than 30nm has been measured from 20to 100K. The observed thermal conductance shows unusual linear temperature dependence at low temperatures, as opposed to the T3 dependence predicted by the conventional phonon transport model. In contrast to previous models, the present study suggests that phonon-boundary scattering is highly frequency dependent, and ranges from nearly ballistic to completely diffusive, which can explain the unexpected linear temperature dependence.

Renkun Chen, Allon I. Hochbaum, Padraig Murphy, Joel Moore, Peidong Yang, and Arun Majumdar

2008-09-02T23:59:59.000Z

248

The Evolution of Epitype  

Science Journals Connector (OSTI)

...Jonathan Arnold, Kristofer Mussar, Wyatt Anderson, Eileen Roy, Benjamin Nelson, and anonymous reviewers contributed useful editorial...107-116. Kusakabe, T. , Araki, I., Satoh, N., and Jeffery, W.R. (1997). Evolution of chordate actin genes: Evidence...

Richard B. Meagher

2010-06-15T23:59:59.000Z

249

Collisional Thermalization of Hydrogen and Helium in Solar Wind Plasma  

E-Print Network [OSTI]

In situ observations of the solar wind frequently show the temperature of $\\alpha$-particles (fully ionized helium), $T_\\alpha$, to significantly differ from that of protons (ionized hydrogen), $T_p$. Many heating processes in the plasma act preferentially on $\\alpha$-particles, even as collisions among ions act to gradually establish thermal equilibrium. Measurements from the $\\textit{Wind}$ spacecraft's Faraday cups reveal that, at $r=1.0\\ \\textrm{AU}$ from the Sun, the observed values of the $\\alpha$-proton temperature ratio, $\\theta_{\\alpha p} \\equiv T_\\alpha\\,/\\,T_p$ has a complex, bimodal distribution. This study applied a simple model for the radial evolution of $\\theta_{\\alpha p}$ to these data to compute expected values of $\\theta_{\\alpha p}$ at $r=0.1\\ \\textrm{AU}$. These inferred $\\theta_{\\alpha p}$-values have no trace of the bimodality seen in the $\\theta_{\\alpha p}$-values measured at $r=1.0\\ \\textrm{AU}$ but are instead consistent with the actions of the known mechanisms for $\\alpha$-particle p...

Maruca, Bennett A; Sorriso-Valvo, Luca; Kasper, Justin C; Stevens, Michael L

2013-01-01T23:59:59.000Z

250

The Thermal Insulation Properties for Wall Material with Various Water Contents  

Science Journals Connector (OSTI)

The thermal conductivities of wall material were measured under various water contents to investigate the effect of water content on the thermal insulation properties. The results show that water contents have adverse impact to heat insulation of wall ... Keywords: the thermal conductivity, water contents, the thermal insulation properties

Zhang Chuancheng; Lu Haijun

2010-05-01T23:59:59.000Z

251

Nonlocal probes of thermalization in holographic quenches with spectral methods  

E-Print Network [OSTI]

We describe the application of pseudo-spectral methods to problems of holographic thermal quenches of relevant couplings in strongly coupled gauge theories. We focus on quenches of a fermionic mass term in a strongly coupled N=4 supersymmetric Yang-Mills plasma, and the subsequent equilibration of the system. From the dual gravitational perspective, we study gravitational collapse of a massive scalar field in asymptotically anti-de-Sitter geometry with a prescribed boundary condition for its non-normalizable mode. Access to the full background geometry of the gravitational collapse allows for the study of nonlocal probes of the thermalization process. We discuss the evolution of the apparent and the event horizons, the two-point correlation functions of operators of large conformal dimensions, and the evolution of the entanglement entropy of the system. We compare the thermalization process from the viewpoint of local (the one-point) correlation functions and these nonlocal probes, finding that the thermaliza...

Buchel, Alex; van Niekerk, Anton

2014-01-01T23:59:59.000Z

252

Thermal comfort during surgery  

E-Print Network [OSTI]

THERMAL COMFORT DURING SURGERY A Thesis by DAVID HAROLD MANNING Submitted to the Graduate College of Texas A&M University in partial fulfillment of the requirement for the degree of MASTER OF SCIENCE December 1978 Major Subject: Industrial... Engineering THERMAL COMFORT DURING SURGERY A Thesis by DAVID HAROLD MANNING Approved as to style and content by: airman of C it ee Head of Department Member Me er December 1978 ABSTRACT Thermal Comfort During Surgery (December 1978) David Harold...

Manning, David Harold

1978-01-01T23:59:59.000Z

253

A Unified Approach for the Measurement of Individual or Total Volatile Organic Sulfur Compounds in Hydrocarbon Matrices by Dual-Plasma Chemiluminescence Detector and Low Thermal Mass Gas Chromatography  

Science Journals Connector (OSTI)

......ozone (6). In the case of the DP-SCD, a quartz-based heater is enclosed in a low thermal mass metal housing to form the...61: 12681271 (1989). 7. R. Shearer. Development of flameless sulfur chemiluminescence detection: applications to gas chromatography......

Ronda Gras; Jim Luong; Randy Shearer

254

Variable pressure thermal insulating jacket  

DOE Patents [OSTI]

A device for controlled insulation of a thermal device is disclosed. The device includes a thermal jacket with a closed volume able to be evacuated to form an insulating jacket around the thermal source. A getter material is in communication with the closed volume of the thermal jacket. The getter material can absorb and desorb a control gas to control gas pressure in the volume of the thermal jacket to control thermal conductivity in the thermal jacket. 10 figs.

Nelson, P.A.; Malecha, R.F.; Chilenskas, A.A.

1994-09-20T23:59:59.000Z

255

NANO REVIEW Open Access Thermal conductivity and thermal boundary  

E-Print Network [OSTI]

NANO REVIEW Open Access Thermal conductivity and thermal boundary resistance of nanostructures and the thermal transport prop- erties is a key point to design materials with preferred thermal properties with the heat dissipation on them. The influence of the interfacial roughness on the thermal conductivity

Boyer, Edmond

256

Interface and nanostructure evolution of cobalt germanides on Ge(001)  

SciTech Connect (OSTI)

Cobalt germanide (Co{sub x}Ge{sub y}) is a candidate system for low resistance contact modules in future Ge devices in Si-based micro and nanoelectronics. In this paper, we present a detailed structural, morphological, and compositional study on Co{sub x}Ge{sub y} formation on Ge(001) at room temperature metal deposition and subsequent annealing. Scanning tunneling microscopy and low energy electron diffraction clearly demonstrate that room temperature deposition of approximately four monolayers of Co on Ge(001) results in the Volmer Weber growth mode, while subsequent thermal annealing leads to the formation of a Co-germanide continuous wetting layer which evolves gradually towards the growth of elongated Co{sub x}Ge{sub y} nanostructures. Two types of Co{sub x}Ge{sub y} nanostructures, namely, flattop- and ridge-type, were observed and a systematic study on their evolution as a function of temperature is presented. Additional transmission electron microscopy and x-ray photoemission spectroscopy measurements allowed us to monitor the reaction between Co and Ge in the formation process of the Co{sub x}Ge{sub y} continuous wetting layer as well as the Co{sub x}Ge{sub y} nanostructures.

Grzela, T., E-mail: grzela@ihp-microelectronics.com; Schubert, M. A. [IHP, Im Technologiepark 25, 15236 Frankfurt (Oder) (Germany); Koczorowski, W. [London Centre for Nanotechnology, University College London, 17-19 Gordon Street, London, WC1H 0AH,United Kingdom (United Kingdom); Institute of Physics, Poznan University of Technology, Nieszawska 13A, 60-965 Poznan (Poland); Capellini, G. [IHP, Im Technologiepark 25, 15236 Frankfurt (Oder) (Germany); Dipartimento di Scienze, Universit degli Studi Roma Tre, I-00146 Roma (Italy); Czajka, R. [Institute of Physics, Poznan University of Technology, Nieszawska 13A, 60-965 Poznan (Poland); Radny, M. W. [Institute of Physics, Poznan University of Technology, Nieszawska 13A, 60-965 Poznan (Poland); School of Mathematical and Physical Sciences, The University of Newcastle, University Drive, Callaghan NSW, 2308 (Australia); Curson, N.; Schofield, S. R. [London Centre for Nanotechnology, University College London, 17-19 Gordon Street, London, WC1H 0AH,United Kingdom (United Kingdom); Schroeder, T. [IHP, Im Technologiepark 25, 15236 Frankfurt (Oder) (Germany); BTU Cottbus, Konrad-Zuse Str. 1, 03046 Cottbus (Germany)

2014-02-21T23:59:59.000Z

257

Three dimensional fabric evolution of sheared sand  

SciTech Connect (OSTI)

Granular particles undergo translation and rolling when they are sheared. This paper presents a three-dimensional (3D) experimental assessment of fabric evolution of sheared sand at the particle level. F-75 Ottawa sand specimen was tested under an axisymmetric triaxial loading condition. It measured 9.5 mm in diameter and 20 mm in height. The quantitative evaluation was conducted by analyzing 3D high-resolution x-ray synchrotron micro-tomography images of the specimen at eight axial strain levels. The analyses included visualization of particle translation and rotation, and quantification of fabric orientation as shearing continued. Representative individual particles were successfully tracked and visualized to assess the mode of interaction between them. This paper discusses fabric evolution and compares the evolution of particles within and outside the shear band as shearing continues. Changes in particle orientation distributions are presented using fabric histograms and fabric tensor.

Hasan, Alsidqi; Alshibli, Khalid (UWA)

2012-10-24T23:59:59.000Z

258

Thermal history sensing with thermographic phosphors  

Science Journals Connector (OSTI)

The ability to measure temperatures on high thermal loaded components in gas turbines and similar prime movers is critical during the design phase if the performance of cooling strategies is to be confirmed. Restricted access and the extreme environment mean that on-line temperature measurement is not always possible and that off-line temperature techniques employing thermal history sensors are sometimes necessary. The authors have developed a new type of sensor based on ceramic phosphors. These show bright narrow band emission that is easily detected and distinguished from the background. Crystallization phase change and diffusion are all temperature dependent processes that affect the emission characteristics and that with proper calibration can be used to form a phosphor based thermal history sensor. Results from the calibration of crystallization in Y 2 SiO 5 :Tb and its application in the form of a temperature indicating paint are reviewed. A new embodiment of the phosphor thermal history sensor concept is then presented comprising a YSZ/YAG:Dy composite applied using air plasma spraying in the form of a thermal barrier coating. The coating is shown to function as a thermal history sensor albeit with a limited dynamic range.

A. L. Heyes; A. Rabhiou; J. P. Feist; A. Kempf

2013-01-01T23:59:59.000Z

259

E-Print Network 3.0 - adiabatic quantum evolution Sample Search...  

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

Chinese Academy of Sciences Collection: Physics 34 Quantum measurement via Born-Oppenheimer adiabatic dynamics C. P. Sun,1,2 Summary: , the adiabatic evolution of the system...

260

Evolution Vs. Thermodynamics  

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

Evolution Vs. Thermodynamics Evolution Vs. Thermodynamics Name: Murphy iii Status: N/A Age: N/A Location: N/A Country: N/A Date: Around 1993 Question: Does the THEORY of evolution contradict the Second Law of thermodynamics? If not, how can an organic system grow in complexity in light of that law? Do not even try to tell me that hot methane soup has less chaos than cool DNA. Replies: The second law only says that the entropy (disorder) of a complete closed system must increase with time, not that the orderliness of one part of that system cannot increase. Increasing complexity of life must be balanced with more increase of disorder somewhere else in the system. Life itself increases order, but only of a small part of the overall system, whose entropy, when all parts are added up, must always be increasing

Note: This page contains sample records for the topic "measuring thermal evolution" 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

Thermal Insulation of Houses  

Science Journals Connector (OSTI)

... THE Thermal Insulation (Dwellings) Bill which Mr. G. Nabarro introduced into the House of Commons on ... , sponsored by members of both major political parties, extends the principle of the Thermal Insulation (Industrial Buildings) Act of July 1957 to all new dwelling houses built in the ...

1958-02-22T23:59:59.000Z

262

Mechanical Engineering & Thermal Group  

E-Print Network [OSTI]

Mechanical Engineering & Thermal Group The Mechanical Engineering (ME) & Thermal Group at LASP has, and ground- based mechanical systems. Instrument Design Building on decades of design experience that has evolved with the complexity of instrument design demands, LASP mechanical engineers develop advanced

Mojzsis, Stephen J.

263

Ambient variation-tolerant and inter components aware thermal management for mobile system on chips  

E-Print Network [OSTI]

, such as thermal conductivity and heat capacity of the package including cover, display and battery are measuredAmbient variation-tolerant and inter components aware thermal management for mobile system on chips:josephz@qti.qualcomm.com Abstract-- In this work we measure and study two key aspects of the thermal behavior of smartphones: 1

Simunic, Tajana

264

Thermal Recovery Methods  

SciTech Connect (OSTI)

Thermal Recovery Methods describes the basic concepts of thermal recovery and explains the injection patterns used to exploit reservoir conditions. Basic reservoir engineering is reviewed with an emphasis on changes in flow characteristics caused by temperature. The authors discuss an energy balance for steam and combustion drive, and they explain in situ reactions. Heat loss, combustion drive, and steam displacement also are examined in detail, as well as cyclic steam injection, downhole ignition, well heating, and low-temperature oxidation. Contents: Thermal processes; Formation and reservoir evaluations; Well patterns and spacing; Flow and process equations; Laboratory simulation of thermal recovery; Heat loss and transmission; Displacement and production; Equipment; Basic data for field selection; Laboratory evaluation of combustion characteristics; Thermal properties of reservoirs and fluids.

White, P.D.; Moss, J.T.

1983-01-01T23:59:59.000Z

265

Tunable thermal link  

DOE Patents [OSTI]

Disclosed is a device whereby the thermal conductance of a multiwalled nanostructure such as a multiwalled carbon nanotube (MWCNT) can be controllably and reversibly tuned by sliding one or more outer shells with respect to the inner core. As one example, the thermal conductance of an MWCNT dropped to 15% of the original value after extending the length of the MWCNT by 190 nm. The thermal conductivity returned when the tube was contracted. The device may comprise numbers of multiwalled nanotubes or other graphitic layers connected to a heat source and a heat drain and various means for tuning the overall thermal conductance for applications in structure heat management, heat flow in nanoscale or microscale devices and thermal logic devices.

Chang, Chih-Wei; Majumdar, Arunava; Zettl, Alexander K.

2014-07-15T23:59:59.000Z

266

Solar thermal aircraft  

DOE Patents [OSTI]

A solar thermal powered aircraft powered by heat energy from the sun. A heat engine, such as a Stirling engine, is carried by the aircraft body for producing power for a propulsion mechanism, such as a propeller. The heat engine has a thermal battery in thermal contact with it so that heat is supplied from the thermal battery. A solar concentrator, such as reflective parabolic trough, is movably connected to an optically transparent section of the aircraft body for receiving and concentrating solar energy from within the aircraft. Concentrated solar energy is collected by a heat collection and transport conduit, and heat transported to the thermal battery. A solar tracker includes a heliostat for determining optimal alignment with the sun, and a drive motor actuating the solar concentrator into optimal alignment with the sun based on a determination by the heliostat.

Bennett, Charles L. (Livermore, CA)

2007-09-18T23:59:59.000Z

267

Comparison of thermal neutron distributions within shield materials obtained by experiments, SN and monte carlo code calculations  

Science Journals Connector (OSTI)

......The TLDs for thermal neutrons, which consist...measurements of induced activity of gold...measurement of thermal neutron fluence was...region of the energy range 5.04...Watt neutron fission spectrum of 252Cf and......

Yoshihiro Asano; Takeshi Sugita; Takenori Suzaki; Hideyuki Hirose

2005-12-20T23:59:59.000Z

268

Thermal Stability Of Formohydroxamic Acid  

SciTech Connect (OSTI)

The thermal stability of formohydroxamic acid (FHA) was evaluated to address the potential for exothermic decomposition during storage and its use in the uranium extraction process. Accelerating rate calorimetry showed rapid decomposition at a temperature above 65 {degree}?C; although, the rate of pressure rise was greater than two orders of magnitude less than the lower bound for materials which have no explosive properties with respect to transportation. FHA solutions in water and nitric acid did not reach runaway conditions until 150 {degree}?C. Analysis by differential scanning calorimetry showed that FHA melted at 67 {degree}?C and thermally decomposed at 90 {degree}?C with an enthalpy of -1924 J/g. The energics of the FHA thermal decomposition are comparable to those measured for aqueous solutions of hydroxylamine nitrate. Solid FHA should be stored in a location where the temperature does not exceed 20-25 {degree}?C. As a best practice, the solid material should be stored in a climate-controlled environment such as a refrigerator or freezer. FHA solutions in water are not susceptible to degradation by acid hydrolysis and are the preferred way to handle FHA prior to use.

Fondeur, F. F.; Rudisill, T. S.

2011-10-21T23:59:59.000Z

269

High-Temperature Thermal Array for Next Generation Solar Thermal...  

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

Thermal Array for Next Generation Solar Thermal Power Production Award Number: DE-EE00025828 Report Date: March 15, 2013 PI: Stephen Obrey * Technical approach is focused on...

270

Thermal Modeling and Device Noise Properties of Three-Dimensional-SOI Technology  

E-Print Network [OSTI]

Thermal test structures and ring oscillators (ROs) are fabricated in 0.18-mum three-dimensional (3-D)-SOI technology. Measurements and electrothermal simulations show that thermal and parasitic effects due to 3-D packaging ...

Chen, Tze Wee

271

Numerical Modeling of the Transient Thermal Interference of Vertical U-Tube Haet Exchangers  

E-Print Network [OSTI]

installation separation range. Non-homogenous media were modeled by varying backfill thermal conductivity. Maximum heat transfer was achieved with a fictitious backfill thermal conductivity of 1,000 W/m-K, while measured bentonite backfill conductivities were...

Muraya, Norman K.

272

Thermal Conductivity of Certain Rock Types and its Relevance to the Storage of Nuclear Waste  

Science Journals Connector (OSTI)

Nine rocks selected from the surface of three plutons have been examined petrographically and their thermal conductivities measured in the temperature range of 100 to 500C. The thermal conductivities of differe...

V. V. Mirkovich; J. A. Soles

1978-01-01T23:59:59.000Z

273

Locality, entanglement, and thermalization of isolated quantum systems  

Science Journals Connector (OSTI)

A way to understand thermalization in an isolated system is to interpret it as an increase in entanglement between subsystems. Here we test this idea through a combination of analytical and Krylov-subspace-based numerical methods applied to a quantum gas of bosons. We find that the entanglement entropy of a subsystem is rapidly generated at the initial state of the evolution, to quickly approach the thermal value. Our results also provide an accurate numerical test of the eigenstate thermalization hypothesis (ETH), according to which a single energy eigenstate of an isolated system behaves in certain respects as a thermal state. In the context of quantum black holes, we propose that the ETH is a quantum version of the classical no-hair theorem.

S. Khlebnikov and M. Kruczenski

2014-11-03T23:59:59.000Z

274

ECOLOGY & EVOLUTION CONSERVATION BIOLOGY  

E-Print Network [OSTI]

.arlettaz@iee.unibe.ch www.conservation.unibe.ch Grassland management: designing tomorrow's farmland for biodiversity 1ECOLOGY & EVOLUTION CONSERVATION BIOLOGY Prof. Dr Raphaël Arlettaz Head of the division of Conservation Biology Office: Erlachstrasse 9a Mail: Baltzerstrasse 6 CH­3012 Bern +41 31 631 31 61 +41 79 637

Richner, Heinz

275

Thermal and electrostrictive expansion characteristics of MLC (Multilayer Ceramic) capacitors  

SciTech Connect (OSTI)

We have measured by strain gauge technique, in-plane thermal expansivity (coefficient of thermal expansion) as a function of temperature and electrostrictive expansion as a function of applied DC voltage for ceramic capacitors with X7R, NPO and N1500 dielectrics. Multilayer Ceramic (MLC) capacitor materials from two commercial suppliers were evaluated. Thermal expansivities of these materials were compared to polyimide-quartz boards and alumina ceramic substrates. 4 refs., 9 figs., 1 tab.

Chanchani, R.; Hall, C.A.

1991-01-01T23:59:59.000Z

276

Interaction between Thermal Phonons and Dislocations in LiF  

Science Journals Connector (OSTI)

Thermal conductivity measurements on deformed LiF crystals from 0.04 to 0.8 K have indicated a strong polarization- and frequency-dependent dynamic scattering of thermal phonons by mobile dislocations. Heat-pulse experiments at 3.6 K have verified both the strength and polarization dependence of the scattering mechanism. The scattering of thermal phonons by sessile dislocations was too weak to be detected.

A. C. Anderson and M. E. Malinowski

1972-04-15T23:59:59.000Z

277

Operating temperatures of recessed fluorescent fixtures with thermal insulation  

SciTech Connect (OSTI)

Tests were performed to determine steady state surface temperatures for recessed fluorescent fixtures operated with and without thermal insulation on the top side of the fixture and to identify potential problems associated with the installation of thermal insulation. In addition to measuring temperatures, means were sought by which the fixtures can be thermally insulated and operated without fire hazards or damage to the fixture. (MCW)

Yarbrough, D.W.; Toor, I.A.

1981-05-01T23:59:59.000Z

278

Evolution of Life on Earth EVOLUTION OF LIFE ON EARTH  

E-Print Network [OSTI]

Evolution of Life on Earth #12;EVOLUTION OF LIFE ON EARTH #12;Earth ~4.5 billion years ago A bad day .... #12;Old (Archean) Rocks #12;4.4 Billion year old Zircon Earth was temperate and had water 4.4 billion years ago! #12;#12;EVOLUTION OF LIFE ON EARTH #12;Making Organic Molecules : Miller & Urey Famous

Shirley, Yancy

279

Definition: Thermal energy | Open Energy Information  

Open Energy Info (EERE)

Definition Definition Edit with form History Facebook icon Twitter icon » Definition: Thermal energy Jump to: navigation, search Dictionary.png Thermal energy The kinetic energy associated with the random motions of the molecules of a material or object; often used interchangeably with the terms heat and heat energy. Measured in joules, calories, or Btu.[1][2][3] View on Wikipedia Wikipedia Definition Thermal energy is the part of the total potential energy and kinetic energy of an object or sample of matter that results in the system temperature. It is represented by the variable Q, and can be measured in Joules. This quantity may be difficult to determine or even meaningless unless the system has attained its temperature only through warming (heating), and not been subjected to work input or output, or any other

280

1 Time evolution of observed JulySeptember sea surface 2 temperatureSahel climate teleconnection with removed  

E-Print Network [OSTI]

are synchronous of inphase rainfall excess over the whole Sudan 19 Sahel due to a strengthening of the convergence departure from midlevels above 10°N­18°N associated with air ascents above the Saharan 24 thermal lows, (2 the global warming effect. In this work 46we have chosen to separate thermal evolutions observed in 47the

Boyer, Edmond

Note: This page contains sample records for the topic "measuring thermal evolution" from the National Library of EnergyBeta (NLEBeta).
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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

Early maturation processes in coal.1 Part 1: Pyrolysis mass balances and structural evolution of coalified wood from the2  

E-Print Network [OSTI]

Early maturation processes in coal.1 Part 1: Pyrolysis mass balances and structural evolution of coalified wood from the2 Morwell Brown Coal seam3 4 Elodie Salmon a, c , Françoise Behar a , François Lorant force21 field to simulate the thermal stress. The Morwell coal has been selected to study the thermal22

Paris-Sud XI, Université de

282

REACTOR GROUT THERMAL PROPERTIES  

SciTech Connect (OSTI)

Savannah River Site has five dormant nuclear production reactors. Long term disposition will require filling some reactor buildings with grout up to ground level. Portland cement based grout will be used to fill the buildings with the exception of some reactor tanks. Some reactor tanks contain significant quantities of aluminum which could react with Portland cement based grout to form hydrogen. Hydrogen production is a safety concern and gas generation could also compromise the structural integrity of the grout pour. Therefore, it was necessary to develop a non-Portland cement grout to fill reactors that contain significant quantities of aluminum. Grouts generate heat when they set, so the potential exists for large temperature increases in a large pour, which could compromise the integrity of the pour. The primary purpose of the testing reported here was to measure heat of hydration, specific heat, thermal conductivity and density of various reactor grouts under consideration so that these properties could be used to model transient heat transfer for different pouring strategies. A secondary purpose was to make qualitative judgments of grout pourability and hardened strength. Some reactor grout formulations were unacceptable because they generated too much heat, or started setting too fast, or required too long to harden or were too weak. The formulation called 102H had the best combination of characteristics. It is a Calcium Alumino-Sulfate grout that contains Ciment Fondu (calcium aluminate cement), Plaster of Paris (calcium sulfate hemihydrate), sand, Class F fly ash, boric acid and small quantities of additives. This composition afforded about ten hours of working time. Heat release began at 12 hours and was complete by 24 hours. The adiabatic temperature rise was 54 C which was within specification. The final product was hard and displayed no visible segregation. The density and maximum particle size were within specification.

Steimke, J.; Qureshi, Z.; Restivo, M.; Guerrero, H.

2011-01-28T23:59:59.000Z

283

Enhanced performance of high temperature aluminate cementitious materials incorporated with Cu powders for thermal energy storage  

Science Journals Connector (OSTI)

Abstract Cementitious materials have been extensively developed in thermal energy storage system of solar thermal power. This paper deals with the volume heat capacity, thermal conductivity, thermal expansion coefficient, and compressive strength of aluminate cementitious thermal energy storage materials with the addition of metal Cu powders. The specimens were subjected to heat-treatment at 105, 350, and 900C, respectively. In the heating process, Cu powders gradually oxidized to Cu2O and CuO, providing a so-called mass compensation mechanism for the composite paste. Meanwhile, it indicates that volume heat capacity and thermal conductivity both increase with increasing Cu powders content and decrease with the rising temperature. The optimum thermal properties were obtained at 15wt% Cu powders loading. In addition, Calorimetric Test, XRD, TGDSC, and MIP are performed for characterizing the hydration rates, the phases, the mass/heat evolution, and the pore distribution, respectively.

Huiwen Yuan; Yu Shi; Chunhua Lu; Zhongzi Xu; Yaru Ni; Xianghui Lan

2015-01-01T23:59:59.000Z

284

Power Grid Growth and Evolution  

Science Journals Connector (OSTI)

This chapter models and analyzes in detail the slow dynamics in power grids. The driving forces for power grid evolutions are identified and then utilized to construct the general evolution model for complex power grids

Shengwei Mei; Xuemin Zhang; Ming Cao

2011-01-01T23:59:59.000Z

285

Theory of delayed thermal fluorescence  

Science Journals Connector (OSTI)

A theory of nonradiative thermal activation involved in delayed thermal fluorescence has been developed from the viewpoint of the breakdown of the Born-Oppenheimer adiabatic approximation.

S. H. Lin

1971-01-01T23:59:59.000Z

286

Thermal insulations using vacuum panels  

DOE Patents [OSTI]

Thermal insulation vacuum panels are formed of an inner core of compressed low thermal conductivity powders enclosed by a ceramic/glass envelope evaluated to a low pressure.

Glicksman, Leon R. (Lynnfield, MA); Burke, Melissa S. (Pittsburgh, PA)

1991-07-16T23:59:59.000Z

287

Thermally driven circulation  

E-Print Network [OSTI]

Several problems connected by the theme of thermal forcing are addressed herein. The main topic is the stratification and flow field resulting from imposing a specified heat flux on a fluid that is otherwise confined to a ...

Nelken, Haim

1987-01-01T23:59:59.000Z

288

Manipulation of Thermal Phonons  

E-Print Network [OSTI]

to manipulate the behavior of phonons is crucial for both energy applications and the cooling of integrated circuits. A novel class of artificially periodic structured materials phononic crystals might make manipulation of thermal phonons possible. In many...

Hsu, Chung-Hao

2013-03-28T23:59:59.000Z

289

Solar Thermal Energy Storage  

Science Journals Connector (OSTI)

Various types of thermal energy storage systems are introduced and their importance and desired characteristics are outlined. Sensible heat storage, which is one of the most commonly used storage systems in pract...

E. Payko; S. Kaka

1987-01-01T23:59:59.000Z

290

Contact thermal lithography  

E-Print Network [OSTI]

Contact thermal lithography is a method for fabricating microscale patterns using heat transfer. In contrast to photolithography, where the minimum achievable feature size is proportional to the wavelength of light used ...

Schmidt, Aaron Jerome, 1979-

2004-01-01T23:59:59.000Z

291

Neutron stars - thermal emitters  

E-Print Network [OSTI]

Confronting theoretical models with observations of thermal radiation emitted by neutron stars is one of the most important ways to understand the properties of both, superdense matter in the interiors of the neutron stars and dense magnetized plasmas in their outer layers. Here we review the theory of thermal emission from the surface layers of strongly magnetized neutron stars, and the main properties of the observational data. In particular, we focus on the nearby sources for which a clear thermal component has been detected, without being contaminated by other emission processes (magnetosphere, accretion, nebulae). We also discuss the applications of the modern theoretical models of the formation of spectra of strongly magnetized neutron stars to the observed thermally emitting objects.

Potekhin, A Y; Pons, J A

2014-01-01T23:59:59.000Z

292

Thermal Stability of Chelated Indium Activable Tracers  

SciTech Connect (OSTI)

The thermal stability of indium tracer chelated with organic ligands ethylenediaminetetraacetic acid (EDTA) and nitrilotriacetic acid (NTA) was measured for reservoir temperatures of 150, 200, and 240 C. Measurements of the soluble indium concentration was made as a function of time by neutron activation analysis. From the data, approximate thermal decomposition rates were estimated. At 150 C, both chelated tracers were stable over the experimental period of 20 days. At 200 C, the InEDTA concentration remained constant for 16 days, after which the thermal decomposition occurred at a measured rate constant of k = 0.09 d{sup -1}. The thermal decomposition of InNTA at 200 C showed a first order reaction with a measured rate constant of k = 0.16 d{sup -1}. At 240 C, both indium chelated tracers showed rapid decomposition with rate constants greater than 1.8 d{sup -1}. The data indicate that for geothermal reservoir with temperatures up to about 200 C, indium chelated tracers can be used effectively for transit times of at least 20 days. These experiments were run without reservoir rock media, and do not account for concomitant loss of indium tracer by adsorption processes.

Chrysikopoulos, Costas; Kruger, Paul

1986-01-21T23:59:59.000Z

293

Thermal conductivity of low density carbon aerogels  

Science Journals Connector (OSTI)

Carbon aerogels with densities ranging from 0.182 to 0.052g/cm3, pore sizes ranging from 88 to 227nm, and particle diameters ranging from 20 to 13nm were prepared. Thermal conductivity measurements by laser fl...

Junzong Feng; Jian Feng; Changrui Zhang

2012-10-01T23:59:59.000Z

294

Texas Thermal Comfort Report  

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

thermal comfort thermal comfort Too often, the systems in our houses are both physically and intellectually inaccessible. In the SNAP House, HVAC components are integrated into the overall structure, and act as an experiential threshold between public and private spaces. They are located in a central, structural chase that supports the clerestory and gives the systems a functional presence within the interior. Each individual component is contained within a single chase

295

Photovoltaic-thermal collectors  

DOE Patents [OSTI]

A photovoltaic-thermal solar cell including a semiconductor body having antireflective top and bottom surfaces and coated on each said surface with a patterned electrode covering less than 10% of the surface area. A thermal-absorbing surface is spaced apart from the bottom surface of the semiconductor and a heat-exchange fluid is passed between the bottom surface and the heat-absorbing surface.

Cox, III, Charles H. (Carlisle, MA)

1984-04-24T23:59:59.000Z

296

Thermal Transport in Suspended and Supported Few-Layer Graphene  

E-Print Network [OSTI]

Thermal Transport in Suspended and Supported Few-Layer Graphene Ziqian Wang,, Rongguo Xie,,,§, Cong few-layer graphene using a thermal-bridge configuration. The room temperature value of is comparable transport of the suspended graphene. The measured values of are generally lower than those from theoretical

Li, Baowen

297

Evolution of fast magnetoacoustic pulses in randomly structured coronal plasmas  

E-Print Network [OSTI]

Magnetohydrodynamic waves interact with structured plasmas and reveal the internal magnetic and thermal structures therein, thereby having seismological applications in the solar atmosphere. We investigate the evolution of fast magnetoacoustic pulses in randomly structured plasmas, in the context of large-scale propagating waves in the solar atmosphere. We perform one dimensional numerical simulations of fast wave pulses propagating perpendicular to a constant magnetic field in a low-$\\beta$ plasma with a random density profile across the field. Both linear and nonlinear regimes are considered. We study how the evolution of the pulse amplitude and width depends on their initial values and the parameters of the random structuring. A randomly structured plasma acts as a dispersive medium for a fast magnetoacoustic pulse, causing amplitude attenuation and broadening of the pulse width. After the passage of the main pulse, secondary propagating and standing fast waves appear in the plasma. Width evolution of both...

Yuan, D; Nakariakov, V M; Li, B; Keppens, R

2014-01-01T23:59:59.000Z

298

Ultrafast thermalization of photoexcited carriers in polar semiconductors  

Science Journals Connector (OSTI)

We present a combined experimental and theoretical study of ultrafast thermalization of high-energy carriers photogenerated by femtosecond laser excitation in GaAs and InP. Luminescence up-conversion is used to monitor the spectral and temporal evolution of the carrier distribution with a time resolution of about 100 fs. A rapid redistribution of electrons and holes over a wide energy range is found within the first 100 fs after excitation. The experimental results are analyzed by Monte Carlo simulations including a molecular-dynamics scheme to describe the carrier kinetics. We show that the Coulomb interaction among carriers is responsible for the initial ultrafast thermalization.

Lucio Rota; Paolo Lugli; Thomas Elsaesser; Jagdeep Shah

1993-02-15T23:59:59.000Z

299

Dynamic modelling for thermal micro-actuators using thermal networks  

E-Print Network [OSTI]

Dynamic modelling for thermal micro-actuators using thermal networks Beatriz L´opez-Wallea,1 and analytical calculations. Key words: Micro-actuators, Thermal modelling, Electrical analogy, Thermal network 1 and MicroMechatronic Systems Department (AS2M), 24 rue Alain Savary, 25000 Besan¸con, France Abstract

Paris-Sud XI, Université de

300

Environment and Protostellar Evolution  

E-Print Network [OSTI]

Even today in our Galaxy, stars form from gas cores in a variety of environments, which may affect the properties of resulting star and planetary systems. Here we study the role of pressure, parameterized via ambient clump mass surface density, on protostellar evolution and appearance, focussing on low-mass, Sun-like stars and considering a range of conditions from relatively low pressure filaments in Taurus, to intermediate pressures of cluster-forming clumps like the Orion Nebula Cluster (ONC), to very high pressures that may be found in the densest Infrared Dark Clouds (IRDCs) or in the Galactic Center (GC). We present unified analytic and numerical models for collapse of prestellar cores, accretion disks, protostellar evolution and bipolar outflows, coupled to radiative transfer (RT) calculations and a simple astrochemical model to predict CO gas phase abundances. Prestellar cores in high pressure environments are smaller and denser and thus collapse with higher accretion rates and efficiencies, resulting...

Zhang, Yichen

2014-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "measuring thermal evolution" 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

Derivation of quantum probabilities from deterministic evolution  

E-Print Network [OSTI]

The predictions of quantum mechanics are probabilistic. Quantum probabilities are extracted using a postulate of the theory called the Born rule, the status of which is central to the "measurement problem" of quantum mechanics. Efforts to justify the Born rule from other physical principles, and thus elucidate the measurement process, have involved lengthy statistical or information-theoretic arguments. Here we show that Bohm's deterministic formulation of quantum mechanics allows the Born rule for measurements on a single system to be derived, without any statistical assumptions. We solve a simple example where the creation of an ensemble of identical quantum states, together with position measurements on those states, are described by Bohm's quantum dynamics. The calculated measurement outcomes agree with the Born-rule probabilities, which are thus a consequence of deterministic evolution. Our results demonstrate that quantum probabilities can emerge from simple dynamical laws alone, and they support the view that there is no underlying indeterminism in quantum phenomena.

T. G. Philbin

2014-10-15T23:59:59.000Z

302

Measurement-Measurement-  

E-Print Network [OSTI]

Internet Measurement- System A Measurement- System B Control System GPS Satellite GPS Satellite GPS Receiver GPS Receiver 2) measurement 3) data1) command Methodology for One-way IP Performance Measurement This paper proposes a methodology for measurement of one-way IP performance metrics such as one-way delay

Jeong, Jaehoon "Paul"

303

Designing a Thermal Energy Storage Program for Electric Utilities  

E-Print Network [OSTI]

Electric utilities are looking at thermal energy storage technology as a viable demand side management (DSM) option. In order for this DSM measure to be effective, it must be incorporated into a workable, well-structured utility program. This paper...

Niehus, T. L.

1994-01-01T23:59:59.000Z

304

Abstract --The influence on the thermal resistance of emitter design parameters like emitter area, aspect ratio, and distance to  

E-Print Network [OSTI]

Abstract -- The influence on the thermal resistance of emitter design parameters like emitter area-state) thermal resistance, but also in a faster thermal transient of the transistors. Accurate RC networks are extracted by measurements in order to model the thermal impedance transient of devices with or without Al

Technische Universiteit Delft

305

Effect of Thermal Hydrolysis on Rheological Behavior of Municipal Sludge  

Science Journals Connector (OSTI)

Effect of Thermal Hydrolysis on Rheological Behavior of Municipal Sludge ... Fenton oxidation facilitated sludge filterability resulting in capillary suction time values which were approximately 50% of the raw sludges, whereas ultrasonication with high input energy deteriorated the filterability. ... Bingham's parameters seem to be able to detect the evolution in sludges quality and in floc strength even at low total suspended solid as the one's usually found in activated sludge processes (less than 10 g l-1). ...

Guohong Feng; Liyan Liu; Wei Tan

2014-06-12T23:59:59.000Z

306

Thermal Gradient Holes At Coso Geothermal Area (1976) | Open Energy  

Open Energy Info (EERE)

Thermal Gradient Holes At Coso Geothermal Area (1976) Thermal Gradient Holes At Coso Geothermal Area (1976) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Thermal Gradient Holes At Coso Geothermal Area (1976) Exploration Activity Details Location Coso Geothermal Area Exploration Technique Thermal Gradient Holes Activity Date 1976 Usefulness useful DOE-funding Unknown Notes Temperatures have been obtained to depths up to 133 m in 22 boreholes with measurements being made at least four times in each borehole. Geothermal gradients ranged from 240C/km to 450 0C/km. References Combs, J. (1 December 1976) Heat flow determinations and implied thermal regime of the Coso geothermal area, California Retrieved from "http://en.openei.org/w/index.php?title=Thermal_Gradient_Holes_At_Coso_Geothermal_Area_(1976)&oldid=511217"

307

CML: Evolution and Design  

E-Print Network [OSTI]

in chemistry. [http://openbabel.org/] Accessed 2011-04-20 #2; http://en.wikipedia.org/wiki/Molecular_graphics ; now the Molecular Graphics and Modelling Society [http://www.mgms.org/] Accessed 2011-04-20 #2; ORTEP: Oak Ridge Thermal Ellipsoid Plot Program... for Crystal Structure Illustrations. Dr. Michael N. Burnett & Dr. Carroll K. Johnson, Oak Ridge National Laboratory, USA. [http://www.ornl.gov/sci/ortep/] Accessed 2011-04-20 #2; Tektronix 4000 text and graphics computer terminals. [http...

Murray-Rust, Peter; Rzepa, Henry S

2011-07-04T23:59:59.000Z

308

Thermal properties for the thermal-hydraulics analyses of the BR2 maximum nominal heat flux.  

SciTech Connect (OSTI)

This memo describes the assumptions and references used in determining the thermal properties for the various materials used in the BR2 HEU (93% enriched in {sup 235}U) to LEU (19.75% enriched in {sup 235}U) conversion feasibility analysis. More specifically, this memo focuses on the materials contained within the pressure vessel (PV), i.e., the materials that are most relevant to the study of impact of the change of fuel from HEU to LEU. This section is regrouping all of the thermal property tables. Section 2 provides a summary of the thermal properties in form of tables while the following sections present the justification of these values. Section 3 presents a brief background on the approach used to evaluate the thermal properties of the dispersion fuel meat and specific heat capacity. Sections 4 to 7 discuss the material properties for the following materials: (i) aluminum, (ii) dispersion fuel meat (UAlx-Al and U-7Mo-Al), (iii) beryllium, and (iv) stainless steel. Section 8 discusses the impact of irradiation on material properties. Section 9 summarizes the material properties for typical operating temperatures. Appendix A elaborates on how to calculate dispersed phase's volume fraction. Appendix B shows the evolution of the BR2 maximum heat flux with burnup.

Dionne, B.; Kim, Y. S.; Hofman, G. L. (Nuclear Engineering Division) [Nuclear Engineering Division

2011-05-23T23:59:59.000Z

309

Leakage Minimization Using Self Sensing and Thermal Alireza Vahdatpour  

E-Print Network [OSTI]

architecture, measuring and modeling techniques, and algorithms for on-line power and energy optimization that can be used for real-time and low overhead measurement of temperature on chip positions where our Measurement, Design Keywords Leakage Energy, Thermal Management, Delay 1. INTRODUCTION There are two principal

Potkonjak, Miodrag

310

THERMAL NEUTRON BACKSCATTER IMAGING.  

SciTech Connect (OSTI)

Objects of various shapes, with some appreciable hydrogen content, were exposed to fast neutrons from a pulsed D-T generator, resulting in a partially-moderated spectrum of backscattered neutrons. The thermal component of the backscatter was used to form images of the objects by means of a coded aperture thermal neutron imaging system. Timing signals from the neutron generator were used to gate the detection system so as to record only events consistent with thermal neutrons traveling the distance between the target and the detector. It was shown that this time-of-flight method provided a significant improvement in image contrast compared to counting all events detected by the position-sensitive {sup 3}He proportional chamber used in the imager. The technique may have application in the detection and shape-determination of land mines, particularly non-metallic types.

VANIER,P.; FORMAN,L.; HUNTER,S.; HARRIS,E.; SMITH,G.

2004-10-16T23:59:59.000Z

311

Thermal conductance of metal-metal interfaces  

Science Journals Connector (OSTI)

The thermal conductance of interfaces between Al and Cu is measured in the temperature range 78thermal conductance of the as-deposited Al-Cu interface is 4GWm?2K?1 at room temperature, an order-of-magnitude larger than the phonon-mediated thermal conductance of typical metal-dielectric interfaces. The magnitude and the linear temperature dependence of the conductance are described well by a diffuse-mismatch model for electron transport at interfaces.

Bryan C. Gundrum; David G. Cahill; Robert S. Averback

2005-12-30T23:59:59.000Z

312

Thermal ignition combustion system  

DOE Patents [OSTI]

The thermal ignition combustion system comprises means for providing walls defining an ignition chamber, the walls being made of a material having a thermal conductivity greater than 20 W/m C and a specific heat greater than 480 J/kg C with the ignition chamber being in constant communication with the main combustion chamber, means for maintaining the temperature of the walls above a threshold temperature capable of causing ignition of a fuel, and means for conducting fuel to the ignition chamber. 8 figs.

Kamo, R.; Kakwani, R.M.; Valdmanis, E.; Woods, M.E.

1988-04-19T23:59:59.000Z

313

Scattering Solar Thermal Concentrators  

Broader source: Energy.gov [DOE]

"This fact sheet describes a scattering solar thermal concentrators project awarded under the DOE's 2012 SunShot Concentrating Solar Power R&D award program. The team, led by the Pennsylvania State University, is working to demonstrate a new, scattering-based approach to concentrating sunlight that aims to improve the overall performance and reliability of the collector field. The research team aims to show that scattering solar thermal collectors are capable of achieving optical performance equal to state-of-the-art parabolic trough systems, but with the added benefits of immunity to wind-load tracking error, more efficient land use, and utilization of stationary receivers."

314

Thermal ignition combustion system  

SciTech Connect (OSTI)

The thermal ignition combustion system comprises means for providing walls defining an ignition chamber, the walls being made of a material having a thermal conductivity greater than 20 W/m.degree. C. and a specific heat greater than 480 J/kg.degree. C. with the ignition chamber being in constant communication with the main combustion chamber, means for maintaining the temperature of the walls above a threshold temperature capable of causing ignition of a fuel, and means for conducting fuel to the ignition chamber.

Kamo, Roy (Columbus, IN); Kakwani, Ramesh M. (Columbus, IN); Valdmanis, Edgars (Columbus, IN); Woods, Melvins E. (Columbus, IN)

1988-01-01T23:59:59.000Z

315

Thermal ignition combustion system  

SciTech Connect (OSTI)

A thermal ignition combustion system adapted for use with an internal combustion engine is described comprising: (a) means for providing ignition chamber walls defining an ignition chamber, the chamber walls being made of a material having a thermal conductivity greater than 20 W/m/sup 0/C. and a specific heat greater than 480J/kg/sup 0/C., the ignition chamber being in constant communication with the main combustion chamber; (b) means for maintaining the temperature of the chamber walls above a threshold temperature capable of causing ignition of a fuel; and (c) means for conducting fuel to the ignition chamber.

Kamo, R.; Kakwani, R.M.; Valdmanis, E.; Woods, M.E.

1988-04-19T23:59:59.000Z

316

Thermal test options  

SciTech Connect (OSTI)

Shipping containers for radioactive materials must be qualified to meet a thermal accident environment specified in regulations, such at Title 10, Code of Federal Regulations, Part 71. Aimed primarily at the shipping container design, this report discusses the thermal testing options available for meeting the regulatory requirements, and states the advantages and disadvantages of each approach. The principal options considered are testing with radiant heat, furnaces, and open pool fires. The report also identifies some of the facilities available and current contacts. Finally, the report makes some recommendations on the appropriate use of these different testing methods.

Koski, J.A.; Keltner, N.R.; Sobolik, K.B.

1993-02-01T23:59:59.000Z

317

Mechanisms Underpinning Degradation of Protective Oxides and Thermal Barrier Coatings in High Hydrogen Content (HHC) - Fueled Turbines  

SciTech Connect (OSTI)

The overarching goal of this research program has been to evaluate the potential impacts of coal-derived syngas and high-hydrogen content fuels on the degradation of turbine hot-section components through attack of protective oxides and thermal barrier coatings. The primary focus of this research program has been to explore mechanisms underpinning the observed degradation processes, and connections to the combustion environments and characteristic non-combustible constituents. Based on the mechanistic understanding of how these emerging fuel streams affect materials degradation, the ultimate goal of the program is to advance the goals of the Advanced Turbine Program by developing materials design protocols leading to turbine hot-section components with improved resistance to service lifetime degradation under advanced fuels exposures. This research program has been focused on studying how: (1) differing combustion environments relative to traditional natural gas fired systems affect both the growth rate of thermally grown oxide (TGO) layers and the stability of these oxides and of protective thermal barrier coatings (TBCs); and (2) how low levels of fuel impurities and characteristic non-combustibles interact with surface oxides, for instance through the development of molten deposits that lead to hot corrosion of protective TBC coatings. The overall program has been comprised of six inter-related themes, each comprising a research thrust over the program period, including: (i) evaluating the role of syngas and high hydrogen content (HHC) combustion environments in modifying component surface temperatures, heat transfer to the TBC coatings, and thermal gradients within these coatings; (ii) understanding the instability of TBC coatings in the syngas and high hydrogen environment with regards to decomposition, phase changes and sintering; (iii) characterizing ash deposition, molten phase development and infiltration, and associated corrosive/thermo-chemical attack mechanisms; (iv) developing a mechanics-based analysis of the driving forces for crack growth and delamination, based on molten phase infiltration, misfit upon cooling, and loss of compliance; (v) understanding changes in TGO growth mechanisms associated with these emerging combustion product streams; and (vi) identifying degradation resistant alternative materials (including new compositions or bi-layer concepts) for use in mitigating the observed degradation modes. To address the materials stability concerns, this program integrated research thrusts aimed at: (1) Conducting tests in simulated syngas and HHC environments to evaluate materials evolution and degradation mechanisms; assessing thermally grown oxide development unique to HHC environmental exposures; carrying out high-resolution imaging and microanalysis to elucidate the evolution of surface deposits (molten phase formation and infiltration); exploring thermo-chemical instabilities; assessing thermo-mechanical drivers and thermal gradient effects on degradation; and quantitatively measuring stress evolution due to enhanced sintering and thermo-chemical instabilities induced in the coating. (2) Executing experiments to study the melting and infiltration of simulated ash deposits, and identifying reaction products and evolving phases associated with molten phase corrosion mechanisms; utilizing thermal spray techniques to fabricate test coupons with controlled microstructures to study mechanisms of instability and degradation; facilitating thermal gradient testing; and developing new materials systems for laboratory testing; (3) Correlating information on the resulting combustion environments to properly assess materials exposure conditions and guide the development of lab-scale simulations of material exposures; specification of representative syngas and high-hydrogen fuels with realistic levels of impurities and contaminants, to explore differences in heat transfer, surface degradation, and deposit formation; and facilitating combustion rig testing of materials test coupons.

Mumm, Daniel

2013-08-31T23:59:59.000Z

318

Thermal distribution systems in commercial buildings  

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

Thermal distribution systems in commercial buildings Thermal distribution systems in commercial buildings Title Thermal distribution systems in commercial buildings Publication Type Journal Article LBNL Report Number LBNL-51860 Year of Publication 2003 Authors Diamond, Richard C., Craig P. Wray, Darryl J. Dickerhoff, Nance Matson, and Duo Wang Start Page Chapter Abstract Previous research suggests that HVAC thermal distribution systems in commercial buildings suffer from thermal losses, such as those caused by duct air leakage and poor duct location. Due to a lack of metrics and data showing the potentially large energy savings from reducing these losses, the California building industry has mostly overlooked energy efficiency improvements in this area. The purpose of this project is to obtain the technical knowledge needed to properly measure and understand the energy efficiency of these systems. This project has three specific objectives: to develop metrics and diagnostics for determining system efficiencies, to develop design and retrofit information that the building industry can use to improve these systems, and to determine the energy impacts associated with duct leakage airflows in an existing large commercial building. The primary outcome of this project is the confirmation that duct leakage airflows can significantly impact energy use in large commercial buildings: our measurements indicate that adding 15% duct leakage at operating conditions leads to an increase in fan power of about 25 to 35%. This finding is consistent with impacts of increased duct leakage airflows on fan power that have been predicted by previous simulations. Other project outcomes include the definition of a new metric for distribution system efficiency, the demonstration of a reliable test for determining duct leakage airflows, and the development of new techniques for duct sealing. We expect that the project outcomes will lead to new requirements for commercial thermal distribution system efficiency in future revisions of California's Title 24.

319

Shallow Drilling In The Salton Sea Region, The Thermal Anomaly  

SciTech Connect (OSTI)

During two shallow thermal drilling programs, thermal measurements were obtained in 56 shallow (76.2 m) and one intermediate (457.3 m) depth holes located both onshore and offshore along the southern margin of the Salton Sea in the Imperial Valley, California. These data complete the surficial coverage of the thermal anomaly, revealing the shape and lateral extent of the hydrothermal system. The thermal data show the region of high thermal gradients to extend only a short distance offshore to the north of the Quaternary volcanic domes which are exposed along the southern shore of the Salton Sea. The thermal anomaly has an arcuate shape, about 4 km wide and 12 km long. Across the center of the anomaly, the transition zone between locations exhibiting high thermal gradients and those exhibiting regional thermal gradients is quite narrow. Thermal gradients rise from near regional (0.09 C/m) to extreme (0.83 C/m) in only 2.4 km. The heat flow in the central part of the anomaly is >600 mW/m{sup 2} and in some areas exceeds 1200 mW/m{sup 2}. The shape of the thermal anomaly is asymmetric with respect to the line of volcanoes previously thought to represent the center of the field, with its center line offset south of the volcanic buttes. There is no broad thermal anomaly associated with the magnetic high that extends offshore to the northeast from the volcanic domes. These observations of the thermal anomaly provide important constraints for models of the circulation of the hydrothermal system. Thermal budgets based on a simple model for this hydrothermal system indicate that the heat influx rate for local ''hot spots'' in the region may be large enough to account for the rate of heat flux from the entire Salton Trough.

Newmark, R. L.; Kasameyer, P. W.; Younker, L. W.

1987-01-01T23:59:59.000Z

320

Characterization of Thermal Properties and Interface Development in Cu-In Liquid Phase  

E-Print Network [OSTI]

and thermal resistance in order to determine the relative importance of interfacial resistance and material number DMR-1062898 and Intel Corporation. ApparatusObjectives ·Measure the effective thermal resistance of next generation Copper-Indium composite thermal interface materials ·Adapt the ASTM D5470-06 standard

Collins, Gary S.

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


321

Experimental investigations of plasma perturbation in Thomson scattering applied to thermal plasma diagnostics  

E-Print Network [OSTI]

of TS measurements of electron and ion tem- peratures in atmospheric-pressure thermal plasmas have beenExperimental investigations of plasma perturbation in Thomson scattering applied to thermal plasma ns laser pulses were performed on argon thermal discharge plasma with electron temperature Te 10 000

322

IEEE TRANSACTIONS ON CONTROL SYSTEM TECHNOLOGY 1 Online Parameterization of Lumped Thermal  

E-Print Network [OSTI]

thermal monitoring is indispens- able. Since only the surface temperature of the battery can be measured, a thermal model is needed to estimate the core temperature of the battery, which can be higher and more to automatically identify the parameters of the battery thermal model needed for the onboard estimation

Stefanopoulou, Anna

323

Phase Change Materials for Thermal Energy Storage in Concentrated Solar Thermal Power Plants  

E-Print Network [OSTI]

ENERGY STORAGE FOR CONCENTRATING SOLAR POWER PLANTS,Thermal Energy Storage in Concentrated Solar Thermal PowerThermal Energy Storage in Concentrated Solar Thermal Power

Hardin, Corey Lee

2011-01-01T23:59:59.000Z

324

Phase Change Materials for Thermal Energy Storage in Concentrated Solar Thermal Power Plants  

E-Print Network [OSTI]

CHANGE THERMAL ENERGY STORAGE FOR CONCENTRATING SOLAR POWERfor Thermal Energy Storage in Concentrated Solar Thermalfor Thermal Energy Storage in Concentrated Solar Thermal

Hardin, Corey Lee

2011-01-01T23:59:59.000Z

325

Phase Change Materials for Thermal Energy Storage in Concentrated Solar Thermal Power Plants  

E-Print Network [OSTI]

and Background Solar thermal energy collection is anCHANGE THERMAL ENERGY STORAGE FOR CONCENTRATING SOLAR POWERfor Thermal Energy Storage in Concentrated Solar Thermal

Hardin, Corey Lee

2011-01-01T23:59:59.000Z

326

Cerebellar evolution in Darwin's Finches  

E-Print Network [OSTI]

CEREBELLAR EVOLUTION IN DARWIN' S FINCHES A Thesis by ROBERT SHERMAN ST. JULES Submitted to the Graduate College of Texas MM University in partial fulfillment of roe reouiremert for the degree of MASTER OF SCIENCE May 1977 Major Subject...: Zoology CEREBELLAR EVOLUTION IN DARWIN'S FINCHES A Thesis by ROBERT SHERMAN ST. JULES Approved as to style and content by: Chairman of Committee Head of p'artment Member May 1977 ABSTRACT Cerebellar Evolution in Darwin's Finches. (Hay 1977...

St. Jules, Robert Sherman

2012-06-07T23:59:59.000Z

327

Concrete Chemical Evolution  

SciTech Connect (OSTI)

The objectives of this analysis are to discuss and evaluate testing results that were performed for the M&O by the Pennsylvania State University (PSU) to evaluate the potential long-term evolution of organic admixtures in cementitious materials at elevated temperatures. The testing was designed to help provide a basis for a determination by the Performance Assessment group (PA) of the long-term acceptability and longevity of cementitious materials for repository use. The main purpose of the testing was to assess the evolution of gases (especially CO{sub 2}) from hydrated cement paste at elevated temperatures and to determine the impact on alkalinity, i.e., the pH value of cement paste pore solution. This information in turn can be used as scoping information to determine if further tests of this nature are needed to support PA. As part of this discussion and evaluation of the PSU results, an assessment of alkalinity in a ''cementitious repository'' and an evaluation of organic materials are presented.

D.H. Tang

1998-07-31T23:59:59.000Z

328

Thermal barrier coating  

DOE Patents [OSTI]

A thermal barrier coating for hot gas path components of a combustion turbine based on a zirconia-scandia system. A layer of zirconium scandate having the hexagonal Zr.sub.3 Sc.sub.4 O.sub.12 structure is formed directly on a superalloy substrate or on a bond coat formed on the substrate.

Bowker, Jeffrey Charles (Gibsonia, PA); Sabol, Stephen M. (Orlando, FL); Goedjen, John G. (Oviedo, FL)

2001-01-01T23:59:59.000Z

329

Thermal management of nanoelectronics  

E-Print Network [OSTI]

-state thermoelectric on- spot cooling, requiring efficient thermoelectric materials that can be integrated with the IC are further complicated by the fact that the material's ability to conduct heat deteriorates when at the packaging level but also at the nanoscale materials and device levels. THERMAL CHALLENGES AT NANOSCALE One

330

Thermal Reactor Safety  

SciTech Connect (OSTI)

Information is presented concerning fire risk and protection; transient thermal-hydraulic analysis and experiments; class 9 accidents and containment; diagnostics and in-service inspection; risk and cost comparison of alternative electric energy sources; fuel behavior and experiments on core cooling in LOCAs; reactor event reporting analysis; equipment qualification; post facts analysis of the TMI-2 accident; and computational methods.

Not Available

1980-06-01T23:59:59.000Z

331

IEEE TRANSACTIONS ON CONTROL SYSTEMS TECHNOLOGY, VOL. 21, NO. 5, SEPTEMBER 2013 1745 Online Parameterization of Lumped Thermal  

E-Print Network [OSTI]

Parameterization of Lumped Thermal Dynamics in Cylindrical Lithium Ion Batteries for Core Temperature Estimation the surface temperature of the battery can be measured, a thermal model is needed to estimate the core measurement. A battery thermal model with constant internal resistance is explored first. The identification

Stefanopoulou, Anna

332

High-Temperature Thermal Array for Next Generation Solar Thermal...  

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

3 Q1 High-Temperature Thermal Array for Next Generation Solar Thermal Power Production - FY13 Q1 This document summarizes the progress of this Los Alamos National Laboratory...

333

Impact of Ageing on Thermal Efficiency of Solar Thermal Collectors  

Science Journals Connector (OSTI)

Today it is common practice to calculate the performance of solar thermal systems or solar collectors based on the results of a thermal performance test carried out with a new solar collector. However, for an int...

Elke Streicher; Stephan Fischer

2009-01-01T23:59:59.000Z

334

Global Surface Temperature Measurement for Hypersonic Flight Vehicles.  

E-Print Network [OSTI]

??This dissertation describes the use of permanent-change thermal paints as a technique for global surface temperature measurements on short-duration hypersonic flight vehicles. The thermal paints (more)

Choudhury, Rishabh

2014-01-01T23:59:59.000Z

335

PROTOPLANETARY DISK STRUCTURE WITH GRAIN EVOLUTION: THE ANDES MODEL  

SciTech Connect (OSTI)

We present a self-consistent model of a protoplanetary disk: 'ANDES' ('AccretioN disk with Dust Evolution and Sedimentation'). ANDES is based on a flexible and extendable modular structure that includes (1) a 1+1D frequency-dependent continuum radiative transfer module, (2) a module to calculate the chemical evolution using an extended gas-grain network with UV/X-ray-driven processes and surface reactions, (3) a module to calculate the gas thermal energy balance, and (4) a 1+1D module that simulates dust grain evolution. For the first time, grain evolution and time-dependent molecular chemistry are included in a protoplanetary disk model. We find that grain growth and sedimentation of large grains onto the disk midplane lead to a dust-depleted atmosphere. Consequently, dust and gas temperatures become higher in the inner disk (R {approx}< 50 AU) and lower in the outer disk (R {approx}> 50 AU), in comparison with the disk model with pristine dust. The response of disk chemical structure to the dust growth and sedimentation is twofold. First, due to higher transparency a partly UV-shielded molecular layer is shifted closer to the dense midplane. Second, the presence of big grains in the disk midplane delays the freeze-out of volatile gas-phase species such as CO there, while in adjacent upper layers the depletion is still effective. Molecular concentrations and thus column densities of many species are enhanced in the disk model with dust evolution, e.g., CO{sub 2}, NH{sub 2}CN, HNO, H{sub 2}O, HCOOH, HCN, and CO. We also show that time-dependent chemistry is important for a proper description of gas thermal balance.

Akimkin, V.; Wiebe, D.; Pavlyuchenkov, Ya. [Institute of Astronomy of the RAS, Pyatnitskaya str. 48, Moscow (Russian Federation)] [Institute of Astronomy of the RAS, Pyatnitskaya str. 48, Moscow (Russian Federation); Zhukovska, S.; Semenov, D.; Henning, Th. [Max-Planck-Institute for Astronomy, Koenigstuhl 17, D-69117 Heidelberg (Germany)] [Max-Planck-Institute for Astronomy, Koenigstuhl 17, D-69117 Heidelberg (Germany); Vasyunin, A. [Department of Chemistry, The University of Virginia, VA (United States)] [Department of Chemistry, The University of Virginia, VA (United States); Birnstiel, T., E-mail: akimkin@inasan.ru, E-mail: dwiebe@inasan.ru, E-mail: pavyar@inasan.ru, E-mail: zhukovska@mpia.de, E-mail: semenov@mpia.de, E-mail: henning@mpia.de, E-mail: anton.vasyunin@gmail.com, E-mail: tbirnstiel@cfa.harvard.edu [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States)

2013-03-20T23:59:59.000Z

336

Final Report: Thermal Conductance of Solid-Liquid Interfaces  

SciTech Connect (OSTI)

Research supported by this grant has significantly advanced fundamental understanding of the thermal conductance of solid-liquid interfaces, and the thermal conductivity of nanofluids and nanoscale composite materials. The thermal conductance of interfaces between carbon nanotubes and a surrounding matrix of organic molecules is exceptionally small and this small value of the interface conductance limits the enhancement in thermal conductivity that can be achieved by loading a fluid or a polymer with nanotubes. The thermal conductance of interfaces between metal nanoparticles coated with hydrophilic surfactants and water is relatively high and surprisingly independent of the details of the chemical structure of the surfactant. We extended our experimental methods to enable studies of planar interfaces between surfactant-coated metals and water where the chemical functionalization can be varied between strongly hydrophobic and strongly hydrophilic. The thermal conductance of hydrophobic interfaces establishes an upper-limit of 0.25 nm on the thickness of the vapor-layer that is often proposed to exist at hydrophobic interfaces. Our high-precision measurements of fluid suspensions show that the thermal conductivity of fluids is not significantly enhanced by loading with a small volume fraction of spherical nanoparticles. These experimental results directly contradict some of the anomalous results in the recent literature and also rule-out proposed mechanisms for the enhanced thermal conductivity of nanofluids that are based on modification of the fluid thermal conductivity by the coupling of fluid motion and the Brownian motion of the nanoparticles.

Cahil, David, G.; Braun, Paul, V.

2006-05-31T23:59:59.000Z

337

Thermal Storage of Solar Energy  

Science Journals Connector (OSTI)

Thermal storage is needed to improve the efficiency and usefulness of solar thermal systems. The paper indicates the main storage ... which would greatly increase the practical use of solar energy is more diffi...

H. Tabor

1984-01-01T23:59:59.000Z

338

Vacuum energy and cosmological evolution  

E-Print Network [OSTI]

An expanding universe is not expected to have a static vacuum energy density. The so-called cosmological constant $\\Lambda$ should be an approximation, certainly a good one for a fraction of a Hubble time, but it is most likely a temporary description of a true dynamical vacuum energy variable that is evolving from the inflationary epoch to the present day. We can compare the evolving vacuum energy with a Casimir device where the parallel plates slowly move apart ("expand"). The total vacuum energy density cannot be measured, only the effect associated to the presence of the plates, and then also their increasing separation with time. In the universe there is a nonvanishing spacetime curvature $R$ as compared to Minkowskian spacetime that is changing with the expansion. The vacuum energy density must change accordingly, and we naturally expect $\\delta\\Lambda\\sim R\\sim H^2$. A class of dynamical vacuum models that trace such rate of change can be constructed. They are compatible with the current cosmological data, and conveniently extended can account for the complete cosmic evolution from the inflationary epoch till the present days. These models are very close to the $\\Lambda$CDM model for the late universe, but very different from it at the early times. Traces of the inherent vacuum dynamics could be detectable in our recent past.

Joan Sola

2014-03-03T23:59:59.000Z

339

Cosmological Evolution of Fundamental Constants: From Theory to Experiment  

E-Print Network [OSTI]

In this paper we discuss a possible cosmological time evolution of fundamental constants from the theoretical and experimental point of views. On the theoretical side, we explain that such a cosmological time evolution is actually something very natural which can be described by mechanisms similar to those used to explain cosmic inflation. We then discuss implications for grand unified theories, showing that the unification condition of the gauge coupling could evolve with cosmological time. Measurements of the electron-to-proton mass ratio can test grand unified theories using low energy data. Following the theoretical discussion, we review the current status of precision measurements of fundamental constants and their potential cosmological time dependence.

Xavier Calmet; Matthias Keller

2014-12-05T23:59:59.000Z

340

Characterization of thermally degraded energetic materials  

SciTech Connect (OSTI)

Characterization of the damage state of a thermally degraded energetic material (EM) is a critical first step in understanding and predicting cookoff behavior. Unfortunately, the chemical and mechanical responses of heated EMs are closely coupled, especially if the EM is confined. The authors have examined several EMs in small-scale experiments (typically 200 mg) heated in both constant-volume and constant-load configurations. Fixtures were designed to minimize free volume and to contain gas pressures to several thousand psi. The authors measured mechanical forces or displacements that correlated to thermal expansion, phase transitions, material creep and gas pressurization as functions of temperature and soak time. In addition to these real-time measurements, samples were recovered for postmortem examination, usually with scanning electron microscopy (SEM) and chemical analysis. The authors present results on EMs (HMX and TATB), with binders (e.g., PBX 9501, PBX 9502, LX-14) and propellants (Al/AP/HTPB).

Renlund, A.M.; Miller, J.C.; Trott, W.M.; Erickson, K.L.; Hobbs, M.L.; Schmitt, R.G.; Wellman, G.W.; Baer, M.R.

1997-12-31T23:59:59.000Z

Note: This page contains sample records for the topic "measuring thermal evolution" 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

THERMAL ENERGY STORAGE IN AQUIFERS WORKSHOP  

E-Print Network [OSTI]

Survey of Thermal Energy Storage in Aquifers Coupled withLow Temperature Thermal Energy Storage Program of Oak Ridgefor Seasonal Thermal Energy Storage: An Overview of the DOE-

Authors, Various

2011-01-01T23:59:59.000Z

342

Electric Motor Thermal Management | Department of Energy  

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

Merit Review and Peer Evaluation ape030bennion2011o.pdf More Documents & Publications Motor Thermal Control Electric Motor Thermal Management Electric Motor Thermal Management...

343

Power Electronic Thermal System Performance and Integration ...  

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

More Documents & Publications Motor Thermal Control Thermal Stress and Reliability for Advanced Power Electronics and Electric Machines Integrated Vehicle Thermal Management...

344

THERMAL ENERGY STORAGE IN AQUIFERS WORKSHOP  

E-Print Network [OSTI]

Scale Thermal Energy Storage for Cogeneration and Solarsolar captors, thermal effluents, low cost energy duringSeale Thermal Energy Storage for Cogeneration and Solar

Authors, Various

2011-01-01T23:59:59.000Z

345

Ocean Thermal Extractable Energy Visualization: Final Technical...  

Office of Environmental Management (EM)

Ocean Thermal Extractable Energy Visualization: Final Technical Report Ocean Thermal Extractable Energy Visualization: Final Technical Report Report about the Ocean Thermal...

346

THERMAL ENERGY STORAGE IN AQUIFERS WORKSHOP  

E-Print Network [OSTI]

Survey of Thermal Energy Storage in Aquifers Coupled withconcept of thermal energy storage in aquifers was suggestedAnnual Thermal Energy Storage Contractors' Information

Authors, Various

2011-01-01T23:59:59.000Z

347

Thermal behavior of nickelmetal hydride battery during charging at a wide range of ambient temperatures  

Science Journals Connector (OSTI)

The thermal behavior of D-type NiMH battery during charging was investigated at a wide ... this work. The temperature measurement of the battery was conducted by using a thermal infrared imager put in a highlow...

Kai Zheng Fang; Dao Bin Mu; Shi Chen

2011-07-01T23:59:59.000Z

348

Fire tests on defective tank-car thermal protection systems  

Science Journals Connector (OSTI)

Many railway tank-cars carrying hazardous materials are thermally protected from fire impingement by thermal insulation and a steel jacket applied to the outside of the tank-car shell. Over time, it is possible that the thermal insulation will sag, rip, degrade, or be crushed under the steel jacket. A thermographic technique to determine whether or not a tank has insulation deficiencies has been developed, but it is necessary to determine which thermal deficiencies do not affect a tanks survivability in a fire and which thermal deficiencies must be repaired. In order to develop a guideline in assessing thermal defects, a thermal model and experimental data would be beneficial. A series of fire tests were performed on a quarter-section tank-car mock-up to assist in developing a guideline and to provide validation data for a thermal model. Twelve fire tests, with constant, credible, simulated pool fire conditions, were performed on the tank-car mock-up with various insulation deficiencies. An infrared thermal imaging camera was used to measure the tank wall temperature. The thermal images were useful in determining the temperature profiles across the defects at different times and the transient temperature behaviour at different locations. It was seen that the properly installed thermal protection system significantly reduced the heat transfer from the fire to the tank wall. It was also seen that the steel jacket alone (i.e. 100% defect) acted as a radiation shield and provided a significant level of protection. With small defects, it was observed that the surrounding protected material provided a cooling effect by thermal conduction. A square defect greater than about 40 cm on each side should be considered significant, because unlike smaller defects, there is little benefit from the surrounding material as far as the peak defect temperature is concerned.

J.D.J VanderSteen; A.M Birk

2003-01-01T23:59:59.000Z

349

Liquid metal thermal electric converter  

DOE Patents [OSTI]

A liquid metal thermal electric converter which converts heat energy to electrical energy. The design of the liquid metal thermal electric converter incorporates a unique configuration which directs the metal fluid pressure to the outside of the tube which results in the structural loads in the tube to be compressive. A liquid metal thermal electric converter refluxing boiler with series connection of tubes and a multiple cell liquid metal thermal electric converter are also provided.

Abbin, Joseph P. (Albuquerque, NM); Andraka, Charles E. (Albuquerque, NM); Lukens, Laurance L. (Albuquerque, NM); Moreno, James B. (Albuquerque, NM)

1989-01-01T23:59:59.000Z

350

Chemical Evolution in Sersic 159-03 Observed with Xmm-Newton  

SciTech Connect (OSTI)

Using a new long X-ray observation of the cluster of galaxies Sersic 159-03 with XMM-Newton, we derive radial temperature and abundance profiles using single- and multi-temperature models. The fits to the EPIC and RGS spectra prefer multi-temperature models especially in the core. The radial profiles of oxygen and iron measured with EPIC/RGS and the line profiles in RGS suggest that there is a dip in the O/Fe ratio in the centre of the cluster compared to its immediate surroundings. A possible explanation for the large scale metallicity distribution is that SNIa and SNII products are released in the ICM through ram-pressure stripping of in-falling galaxies. This causes a peaked metallicity distribution. In addition, SNIa in the central cD galaxy enrich mainly the centre of the cluster with iron. This excess of SNIa products is consistent with the low O/Fe ratio we detect in the centre of the cluster. We fit the abundances we obtain with yields from SNIa, SNII and Population-III stars to derive the clusters chemical evolution. We find that the measured abundance pattern does not require a Population-III star contribution. The relative contribution of the number of SNIa with respect to the total number of SNe which enrich the ICM is about 25-50%. Furthermore, we discuss the possible presence of a non-thermal component in the EPIC spectra. A potential source of this non-thermal emission can be inverse-Compton scattering between Cosmic Microwave Background (CMB) photons and relativistic electrons, which are accelerated in bow shocks associated with ram-pressure stripping of in-falling galaxies.

de Plaa, Jelle; Werner, N.; Bykov, A.M.; Kaastra, J.S.; Mendez, M.; Vink, J.; Bleeker, J.A.M.; Bonamente, M.; Peterson, J.R.; /SRON, Utrecht /Utrecht, Astron. Inst.

2006-03-10T23:59:59.000Z

351

Low Conductivity Thermal Barrier Coatings  

E-Print Network [OSTI]

Low Conductivity Thermal Barrier Coatings A Dissertation Presented to The Faculty of the School conductivity of the coatings. The minimum thermal conductivity occurs at a low rotation rate and is 0.8 W intrinsic thermal conductivity, good phase stability and greater resistance to sintering and CMAS attack

Wadley, Haydn

352

LSPE Interim Stowage Thermal Constraints  

E-Print Network [OSTI]

-arm and thermal battery timers require operating temperatures at or above +40°F for reliable starting when·, ' LSPE Interim Stowage Thermal Constraints· Nl,;. ATM1080 PAGE 1 OF 13 DATE 15 December l97l constraints required for thermal integrity are defined. Prepared by:.:Z4·:..=..-~31!::..--.::..·~-:·::....-c

Rathbun, Julie A.

353

Reactor Thermal-Hydraulics  

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

Thermal-Hydraulics Thermal-Hydraulics Dr. Tanju Sofu, Argonne National Laboratory In a power reactor, the energy produced in fission reaction manifests itself as heat to be removed by a coolant and utilized in a thermodynamic energy conversion cycle to produce electricity. A simplified schematic of a typical nuclear power plant is shown in the diagram below. Primary coolant loop Steam Reactor Heat exchanger Primary pump Secondary pump Condenser Turbine Water Although this process is essentially the same as in any other steam plant configuration, the power density in a nuclear reactor core is typically four orders of magnitude higher than a fossil fueled plant and therefore it poses significant heat transfer challenges. Maximum power that can be obtained from a nuclear reactor is often limited by the

354

Enhancing Thermal Conductivity and Reducing Friction  

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

Laboratory currently has several projects underway to develop advanced fluids, films, coatings, and Laboratory currently has several projects underway to develop advanced fluids, films, coatings, and processes to improve thermal conductivity and reduce friction. These measures are helping to increase energy efficiency for next-generation transportation applications. Superhard and Slick Coating (SSC) Opportunity: Friction, wear, and lubrication strongly affect the energy efficiency, durability, and environmental compatibility of

355

Small solar (thermal) water-pumping system  

SciTech Connect (OSTI)

A small solar (thermal) water pump phototype was tested. The pump works on an organic Rankine cycle using refrigerant R113. The design of the pump is described. Detailed temperature and pressure measurements of the working fluid for different operating conditions are performed. The behaviour of the cycle is analysed to get a clear picture of the thermodynamic process. Power-characteristic curves are obtained by a systematic variation of water temperature, pumping head and heat input. 10 refs., 13 figs., 2 tabs.

Spindler, K.; Hahne, E. [Universitaet Stuttgart (Germany)] [Universitaet Stuttgart (Germany); Chandwalker, K. [Stiletto Engineers, Hyderabad (India)] [Stiletto Engineers, Hyderabad (India)

1996-07-01T23:59:59.000Z

356

Thermal energy storage  

Science Journals Connector (OSTI)

Various types of thermal stares for solar systems are surveyed which include: long-term water stores for solar systems; ground storage using soil as an interseasonal energy store; ground-water aquifers; pebble or rock bed storage; phase change storage; solar ponds; high temperature storage; and cold stores for solar air conditioning system. The use of mathematical models for analysis of the storage systems is considered

W.E.J. Neal

1981-01-01T23:59:59.000Z

357

Cylindrical thermal contact conductance  

E-Print Network [OSTI]

of the Mahr-Federal, Inc. respectively facilitated and provided the necessary surface metrology data of the test pieces. Mr. Claude Davis of Corning, Inc. obtained the thermophysical properties of the Ultra Low Expansion Titanium Silicate glass used... as thermal expansion standard. The engineers at National Instruments provided some much-needed advice and software for programming the data acquisition system. The TAMU Physics Machine Shop provided design advice and a couple of last...

Ayers, George Harold

2004-09-30T23:59:59.000Z

358

Thermally actuated thermionic switch  

DOE Patents [OSTI]

A thermally actuated thermionic switch which responds to an increase of temperature by changing from a high impedance to a low impedance at a predictable temperature set point. The switch has a bistable operation mode switching only on temperature increases. The thermionic material may be a metal which is liquid at the desired operation temperature and held in matrix in a graphite block reservoir, and which changes state (ionizes, for example) so as to be electrically conductive at a desired temperature.

Barrus, D.M.; Shires, C.D.

1982-09-30T23:59:59.000Z

359

Mobile Window Thermal Test  

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

Mobile Window Thermal Test (MoWiTT) Facility Mobile Window Thermal Test (MoWiTT) Facility winter.jpg (469135 bytes) The window has come a long way since the days when it was a single pane of glass in a wood frame. Low-emissivity windows were designed to help buildings retain some of the energy that would have leaked out of less efficient windows. Designing efficient window-and-frame systems is one strategy for reducing the energy use of buildings. But the net energy flowing through a window is a combination of temperature- driven thermal flows and transmission of incident solar energy, both of which vary with time. U-factor and solar heat gain coefficient (SHGC), the window properties that control these flows, depend partly on ambient conditions. Window energy flows can affect how much energy a building uses, depending on when the window flows are available to help meet other energy demands within the building, and when they are adverse, adding to building energy use. This leads to a second strategy for reducing building energy use: using the beneficial solar gain available through a window, either for winter heating or for daylighting, while minimizing adverse flows.

360

Planet Formation: Planet Formation: Evolution of The Solar NebulaEvolution of The Solar Nebula  

E-Print Network [OSTI]

Planet Formation: Planet Formation: Evolution of The Solar NebulaEvolution of The Solar Nebula #12;Evolution of the Solar NebulaEvolution of the Solar Nebula 1.1. Nebula collapses into a disk 2000 KTemperatures near the Sun reach 2000 K #12;Evolution of the Solar NebulaEvolution of the Solar

Herrick, Robert R.

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


361

Thermal Diffusivity and Viscosity of Suspensions of Disc Shaped Nanoparticles  

E-Print Network [OSTI]

In this work we conduct a transient heat conduction experiment with an aqueous suspension of nanoparticle disks of Laponite JS, a sol forming grade, using laser light interferometry. The image sequence in time is used to measure thermal diffusivity and thermal conductivity of the suspension. Imaging of the temperature distribution is facilitated by the dependence of refractive index of the suspension on temperature itself. We observe that with the addition of 4 volume % of nano-disks in water, thermal conductivity of the suspension increases by around 30%. A theoretical model for thermal conductivity of the suspension of anisotropic particles by Fricke as well as by Hamilton and Crosser explains the trend of data well. In turn, it estimates thermal conductivity of the Laponite nanoparticle itself, which is otherwise difficult to measure in a direct manner. We also measure viscosity of the nanoparticle suspension using a concentric cylinder rheometer. Measurements are seen to follow quite well, the theoretical relation for viscosity of suspensions of oblate particles that includes up to two particle interaction. This result rules out the presence of clusters of particles in the suspension. The effective viscosity and thermal diffusivity data show that the shape of the particle has a role in determining enhancement of thermophysical properties of the suspension.

Susheel S. Bhandari; K. Muralidhar; Yogesh M Joshi

2014-03-05T23:59:59.000Z

362

Thermal characterization of submicron polyacrylonitrile fibers based on optical heating and electrical thermal sensing  

SciTech Connect (OSTI)

In this work, the thermal diffusivity of single submicron ({approx}800 nm) polyacrylonitrile (PAN) fibers is characterized using the recently developed optical heating and electrical thermal sensing technique. In the experiment, a thin Au film (approximately in the nanometer range) is coated on the surface of nonconductive PAN fibers. A periodically modulated laser beam is used to irradiate suspended individual fibers to achieve noncontact periodical heating. The periodical temperature response of the sample is monitored by measuring the electrical resistance variation of the thin Au coating. The experimental results for three different synthesized PAN fibers with varying Au coating thickness are presented and discussed.

Hou Jinbo; Wang Xinwei; Zhang Lijun [Department of Mechanical Engineering, N104 Walter Scott Engineering Center, University of Nebraska-Lincoln, Lincoln, Nebraska 68588-0656 (United States)

2006-10-09T23:59:59.000Z

363

Spectroscopic measurement of ion temperature and ion velocity distributions in the flux-coil generated FRC  

SciTech Connect (OSTI)

One aim of the flux-coil generated field reversed configuration at Tri Alpha Energy (TAE) is to establish the plasma where the ion rotational energy is greater than the ion thermal energy. To verify this, an optical diagnostic was developed to simultaneously measure the Doppler velocity-shift and line-broadening using a 0.75 m, 1800 groves/mm, spectrometer. The output spectrum is magnified and imaged onto a 16-channel photomultiplier tube (PMT) array. The individual PMT outputs are coupled to high-gain, high-frequency, transimpedance amplifiers, providing fast-time response. The Doppler spectroscopy measurements, along with a survey spectrometer and photodiode-light detector, form a suite of diagnostics that provide insights into the time evolution of the plasma-ion distribution and current when accelerated by an azimuthal-electric field.

Gupta, D.; Gota, H.; Hayashi, R.; Kiyashko, V.; Morehouse, M.; Primavera, S. [Tri Alpha Energy, Inc., Rancho Santa Margarita, California 92688 (United States); Bolte, N. [Tri Alpha Energy, Inc., Rancho Santa Margarita, California 92688 (United States); Department of Physics and Astronomy, University of California, Irvine, California 92697 (United States); Marsili, P. [Department of Physics, University of Pisa, Largo B. Pontecorvo 3, 56127 Pisa (Italy); Roche, T. [Department of Physics and Astronomy, University of California, Irvine, California 92697 (United States); Wessel, F. [Department of Physics and Astronomy, University of California, Irvine, California 92697 (United States); Tri Alpha Energy, Inc., Rancho Santa Margarita, California 92688 (United States)

2010-10-15T23:59:59.000Z

364

Bionics in textiles: flexible and translucent thermal insulations for solar thermal applications  

Science Journals Connector (OSTI)

...translucent thermal insulations for solar thermal applications Thomas Stegmaier...Denkendorf73770 Denkendorf, Germany Solar thermal collectors used at present consist...transparent thermal insulation|solar thermal collector| 1. Introduction...

2009-01-01T23:59:59.000Z

365

THERMAL PROPERTIES OF FIBERBOARD OVERPACK MATERIALS IN THE 9975 SHIPPING PACKAGE  

SciTech Connect (OSTI)

The 9975 shipping package incorporates a cane fiberboard overpack for thermal insulation and impact resistance. Thermal properties (thermal conductivity and specific heat capacity) have been measured on cane fiberboard and a similar wood fiber-based product at several temperatures representing potential storage conditions. While the two products exhibit similar behavior, the measured specific heat capacity varies significantly from prior data. The current data are being developed as the basis to verify that this material remains acceptable over the extended storage time period.

VORMELKER, PHILLIP; DAUGHERTY, W. L.

2005-06-10T23:59:59.000Z

366

PROPERTIES OF FIBERBOARD OVERPACK MATERIAL IN THE 9975 SHIPPING PACKAGE FOLLOWING THERMAL AGING  

SciTech Connect (OSTI)

Many radioactive material shipping packages incorporate cane fiberboard overpacks for thermal insulation and impact resistance. Mechanical, thermal and physical properties have been measured on cane fiberboard following thermal aging in several temperature/humidity environments. Several of the measured properties change significantly over time in the more severe environments, while other properties are relatively constant. These properties continue to be tracked, with the goal of developing a model for predicting a service life under long-term storage conditions.

Daugherty, W

2007-01-10T23:59:59.000Z

367

CALIFORNIA SOLAR INITIATIVE-THERMAL PROGRAMHANDBOOK  

E-Print Network [OSTI]

CALIFORNIA SOLAR INITIATIVE-THERMAL PROGRAMHANDBOOK CALIFORNIA PUBLIC UTILITIES California Solar Initiative Thermal Program Handbook i 1. Introduction to CSI-Thermal Program ..........................................................................3 2.1 Participants in the CSI-Thermal Program

368

Continuous quantum measurement of a light-matter system  

SciTech Connect (OSTI)

Continuous measurements on correlated quantum systems, in addition to providing information on the state vector of the system in question, induce evolution in the unmeasured degrees of freedom conditioned on the measurement outcome. However, experimentally accessing these nontrivial regimes requires high-efficiency measurements over time scales much longer than the temporal resolution of the measurement apparatus. We report the observation of such a continuous conditioned evolution in the state of a light-collective atomic excitation system undergoing photoelectric measurement.

Zhao, R.; Jenkins, S. D.; Campbell, C. J.; Kennedy, T. A. B.; Kuzmich, A. [School of Physics, Georgia Institute of Technology, Atlanta, Georgia 30332-0430 (United States); Matsukevich, D. N. [JQI and Department of Physics, University of Maryland, College Park, Maryland 20742 (United States); Chaneliere, T. [Laboratoire Aime Cotton, CNRS-UPR 3321, Batiment 505, Campus Universitaire, F-91405 Orsay Cedex (France)

2010-03-15T23:59:59.000Z

369

Thermal conductivity of rigid foam insulations for aerospace vehicles  

Science Journals Connector (OSTI)

The present work describes measurements of the effective thermal conductivity of NCFI 24-124 foam, a spray-on foam insulation used formerly on the Space Shuttle external fuel tank. A novel apparatus to measure the effective thermal conductivity of rigid foam at temperatures ranging from 20K to 300K was developed and used to study three samples of NCFI 24-124 foam insulation. In preparation for measurement, the foam samples were either treated with a uniquely designed moisture absorption apparatus or different residual gases to study their impact on the effective thermal conductivity of the foam. The resulting data are compared to other measurements and mathematical models reported in the literature.

M. Barrios; S.W. Van Sciver

2013-01-01T23:59:59.000Z

370

Modeling Solar Energy Technology Evolution breakout session ...  

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

Modeling Solar Energy Technology Evolution breakout session Modeling Solar Energy Technology Evolution breakout session This presentation summarizes the information given on the...

371

A Climatological Study of Thermally Driven Wind Systems of the U.S. Intermountain West  

Science Journals Connector (OSTI)

This paper investigates the diurnal evolution of thermally driven plain-mountain winds, up- and down-valley winds, up- and downslope winds, and land-lake breezes for summer fair weather conditions in four regions of the Intermountain West where ...

Jebb Q. Stewart; C. David Whiteman; W. James Steenburgh; Xindi Bian

2002-05-01T23:59:59.000Z

372

A sintering model for thermal barrier coatings R.G. Hutchinson a  

E-Print Network [OSTI]

Turbine blades in the high-pressure, high-temperature stages of gas turbines are manufactured from creep model is developed for the progressive sintering of ceramic columns in a thermal barrier coating made. Explicit calculations are reported for the evolution of sintering within an array of mud-cracked columns

Fleck, Norman A.

373

Thermal and non-thermal energies in solar flares  

E-Print Network [OSTI]

The energy of the thermal flare plasma and the kinetic energy of the non-thermal electrons in 14 hard X-ray peaks from 9 medium-sized solar flares have been determined from RHESSI observations. The emissions have been carefully separated in the spectrum. The turnover or cutoff in the low-energy distribution of electrons has been studied by simulation and fitting, yielding a reliable lower limit to the non-thermal energy. It remains the largest contribution to the error budget. Other effects, such as albedo, non-uniform target ionization, hot target, and cross-sections on the spectrum have been studied. The errors of the thermal energy are about equally as large. They are due to the estimate of the flare volume, the assumption of the filling factor, and energy losses. Within a flare, the non-thermal/thermal ratio increases with accumulation time, as expected from loss of thermal energy due to radiative cooling or heat conduction. Our analysis suggests that the thermal and non-thermal energies are of the same magnitude. This surprising result may be interpreted by an efficient conversion of non-thermal energy to hot flare plasma.

Pascal Saint-Hilaire; Arnold O. Benz

2005-03-03T23:59:59.000Z

374

Transformer Thermal Modeling: Improving Reliability Using Data Quality Control  

E-Print Network [OSTI]

1 Transformer Thermal Modeling: Improving Reliability Using Data Quality Control Daniel J. Tylavsky--Eventually all large transformers will be dynamically loaded using models updated regularly from field measured data. Models obtained from measured data give more accurate results than models based on transformer

375

Evolution of Low-Mass Population III Stars  

E-Print Network [OSTI]

We present the evolutionary models of metal-free stars in the mass range from 0.8 to 1.2 Msun with up-to-date input physics. The evolution is followed to the onset of hydrogen mixing into a convection, driven by the helium flash at red giant or asymptotic giant branch phase. The models of mass M >= 0.9 Msun undergo the central hydrogen flash, triggered by the carbon production due to the 3-alpha reactions. We find that the border of the off-center and central ignition of helium core flash falls between 1.1 and 1.2 Msun; the models of mass M hydrogen mixing at the tip of red giant branch while the models of M = 1.2 Msun during the helium shell flashes on the asymptotic giant branch. The equation of state for the Coulomb liquid region, where electron conduction and radiation compete, is shown to be important since it affects the thermal state in the helium core and influences the red giant branch evolution. It is also found that the non-resonant term of 3-alpha reactios plays an important role, although it has negligible effect in the evolution of stars of younger populations. We compare our models with the computations by several other sets of authors, to confirm the good agreement except for one study which finds the helium ignition much closer to the center with consequences important for subsequent evolution.

Takuma Suda; Masayuki Y. Fujimoto; Naoki Itoh

2005-04-25T23:59:59.000Z

376

Integrated Vehicle Thermal Management Systems (VTMS) Analysis...  

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

Integrated Vehicle Thermal Management Power Electronic Thermal System Performance and Integration Characterization and Development of Advanced Heat Transfer Technologies...

377

Ultratough, Thermally Stable Polycrystalline Diamond/Silicon...  

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

Ultratough, Thermally Stable Polycrystalline DiamondSilicon Carbide Nanocomposites for Drill Bits Ultratough, Thermally Stable Polycrystalline DiamondSilicon Carbide...

378

Research program of determination of geological age by thermal analysis method  

Science Journals Connector (OSTI)

On the basis of previous research achievements of measuring the solid state nuclear track in apatite by thermal analysis method, the author further proposes the research program to measure the energy deposited by...

Tongsuo Yang ???; Duqiang Xin ???; Tuanbu Wang ???

2013-08-01T23:59:59.000Z

379

Spectroscopy of infrared emission characteristics of thermal power plant boiler coal ash deposits  

Science Journals Connector (OSTI)

Thermal radiation characteristics of ash deposits on a coal combustion boiler of an electric power plant are investigated. Normal emittance spectra in 2.5-25 m wavelength region and total normal emittance are measured on four kinds of ash at 600-1100K ... Keywords: ash deposit, emittance, pulverized coal combustion boiler furnace, spectroscopic measurement, thermal radiation

Aleksandar Saljnikov; Darko Goricanec; Danijela Dobersek; Dorde Kozic

2007-05-01T23:59:59.000Z

380

Abstract--Eventually, prediction of transformer thermal performance for dynamic loading will be made using models  

E-Print Network [OSTI]

1 Abstract--Eventually, prediction of transformer thermal performance for dynamic loading will be made using models distilled from measure data, rather than models derived from transformer heat for measuring the acceptability of transformer thermal models. For a model to be acceptable, it must have

Note: This page contains sample records for the topic "measuring thermal evolution" 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

STUDY OF THERMAL SENSITIVITY AND THERMAL EXPLOSION VIOLENCE OF ENERGETIC MATERIALS IN THE LLNL ODTX SYSTEM  

SciTech Connect (OSTI)

Some energetic materials may explode at fairly low temperatures and the violence from thermal explosion may cause a significant damage. Thus it is important to understand the response of energetic materials to thermal insults for safe handling and storage of energetic materials. The One Dimensional Time to Explosion (ODTX) system at the Lawrence Livermore National Laboratory can measure times to explosion, lowest explosion temperatures, and determine kinetic parameters of energetic materials. Samples of different configurations can be tested in the system. The ODTX testing can also generate useful data for determining thermal explosion violence of energetic materials. We also performed detonation experiments of LX-10 in aluminum anvils to determine the detonation violence and validated the Zerilli Armstrong aluminum model. Results of the detonation experiments agreed well with the model prediction.

HSU, P C; Hust, G; May, C; Howard, M; Chidester, S K; Springer, H K; Maienschein, J L

2011-08-03T23:59:59.000Z

382

Crystallographic texture evolution in high-density polyethylene during uniaxial tension  

E-Print Network [OSTI]

Crystallographic texture evolution in high-density polyethylene during uniaxial tension D. Lia , H experimental measurements of crystallographic texture evolution in high-density polyethylene subjected to very straining of high-density polyethylene to large strains. There are at least three distinct preferred

Garmestani, Hamid

383

Evolution Securities Ltd formerly Evolution Beeson Gregory | Open Energy  

Open Energy Info (EERE)

Securities Ltd formerly Evolution Beeson Gregory Securities Ltd formerly Evolution Beeson Gregory Jump to: navigation, search Name Evolution Securities Ltd (formerly Evolution Beeson Gregory) Place London, United Kingdom Zip EC2V 7AN Product Evolution Securities is the investment banking business of Evolution Group plc providing equity research, institutional sales and trading and corporate finance advice. Coordinates 51.506325°, -0.127144° 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":51.506325,"lon":-0.127144,"alt":0,"address":"","icon":"","group":"","inlineLabel":"","visitedicon":""}]}

384

Constraining the intra-cluster pressure profile from the thermal SZ power spectrum  

E-Print Network [OSTI]

The angular power spectrum of the thermal Sunyaev-Zel'dovich (tSZ) effect is highly sensitive to cosmological parameters such as sigma8 and OmegaM, but its use as a precision cosmological probe is hindered by the astrophysical uncertainties in modeling the gas pressure profile in galaxy groups and clusters. In this paper we assume that the relevant cosmological parameters are accurately known, and explore the ability of current and future tSZ power spectrum measurements to constrain the intra-cluster gas pressure or the evolution of the gas mass fraction, f_gas. We use the CMB bandpower measurements from the South Pole Telescope and a Bayesian MCMC method to quantify deviations from the standard, universal gas pressure model. We explore analytical model extensions that bring the predictions for the tSZ power in agreement with experimental data. We find that a steeper pressure profile in the cluster outskirts or an evolving f_gas have mild to severe conflicts with experimental data or simulations. Varying more...

Ramos-Ceja, M E; Pacaud, F; Bertoldi, F

2014-01-01T23:59:59.000Z

385

Thermally switchable dielectrics  

DOE Patents [OSTI]

Precursor polymers to conjugated polymers, such as poly(phenylene vinylene), poly(poly(thiophene vinylene), poly(aniline vinylene), and poly(pyrrole vinylene), can be used as thermally switchable capacitor dielectrics that fail at a specific temperature due to the non-conjugated precursor polymer irreversibly switching from an insulator to the conjugated polymer, which serves as a bleed resistor. The precursor polymer is a good dielectric until it reaches a specific temperature determined by the stability of the leaving groups. Conjugation of the polymer backbone at high temperature effectively disables the capacitor, providing a `built-in` safety mechanism for electronic devices.

Dirk, Shawn M.; Johnson, Ross S.

2013-04-30T23:59:59.000Z

386

Constraining Solar Flare Differential Emission Measures with EVE and RHESSI  

E-Print Network [OSTI]

Deriving a well-constrained differential emission measure (DEM) distribution for solar flares has historically been difficult, primarily because no single instrument is sensitive to the full range of coronal temperatures observed in flares, from $\\lesssim$2 to $\\gtrsim$50 MK. We present a new technique, combining extreme ultraviolet (EUV) spectra from the EUV Variability Experiment (EVE) onboard the Solar Dynamics Observatory with X-ray spectra from the Reuven Ramaty High Energy Solar Spectroscopic Imager (RHESSI), to derive, for the first time, a self-consistent, well-constrained DEM for jointly-observed solar flares. EVE is sensitive to ~2-25 MK thermal plasma emission, and RHESSI to $\\gtrsim$10 MK; together, the two instruments cover the full range of flare coronal plasma temperatures. We have validated the new technique on artificial test data, and apply it to two X-class flares from solar cycle 24 to determine the flare DEM and its temporal evolution; the constraints on the thermal emission derived from ...

Caspi, Amir; Warren, Harry P

2014-01-01T23:59:59.000Z

387

Thermal and non-thermal energies in solar flares  

E-Print Network [OSTI]

The energy of the thermal flare plasma and the kinetic energy of the non-thermal electrons in 14 hard X-ray peaks from 9 medium-sized solar flares have been determined from RHESSI observations. The emissions have been carefully separated in the spectrum. The turnover or cutoff in the low-energy distribution of electrons has been studied by simulation and fitting, yielding a reliable lower limit to the non-thermal energy. It remains the largest contribution to the error budget. Other effects, such as albedo, non-uniform target ionization, hot target, and cross-sections on the spectrum have been studied. The errors of the thermal energy are about equally as large. They are due to the estimate of the flare volume, the assumption of the filling factor, and energy losses. Within a flare, the non-thermal/thermal ratio increases with accumulation time, as expected from loss of thermal energy due to radiative cooling or heat conduction. Our analysis suggests that the thermal and non-thermal energies are of the same m...

Saint-Hilaire, P; Saint-Hilaire, Pascal; Benz, Arnold O.

2005-01-01T23:59:59.000Z

388

High Temperature Thermal Array for Next Generation Solar Thermal...  

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

A 10% increase in shaft work is directly attributable to modified thermal heat capacity Engineering HTF Specific heat yields modified power output. 27 127 227 327 427 527...

389

Paleomagnetic Measurements | Open Energy Information  

Open Energy Info (EERE)

Paleomagnetic Measurements Paleomagnetic Measurements Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Technique: Paleomagnetic Measurements Details Activities (1) Areas (1) Regions (0) NEPA(0) Exploration Technique Information Exploration Group: Lab Analysis Techniques Exploration Sub Group: Rock Lab Analysis Parent Exploration Technique: Rock Lab Analysis Information Provided by Technique Lithology: Can determine detailed information about rock composition and morphology Stratigraphic/Structural: Historic structure and deformation of land Hydrological: Thermal: Dictionary.png Paleomagnetic Measurements: Paleomagnetism is the study of remnant magnetization in rocks. Paleomagnetic measurements are measurements of the magnetic properties in rocks; these properties are locked in during the formation of the rock. A

390

TMX-U thermal-barrier experiments  

SciTech Connect (OSTI)

This review of thermal-barrier experiments in the Tandem Mirror Experiment Upgrade (TMX-U) describes our progress at Lawrence Livermore National Laboratory in plasma confinement and central-cell heating. Thermal barriers in TMX-U improved axial confinement by two orders of magnitude over a limited range of densities, compared with confinement in single-cell mirrors at the same ion temperature. Our study shows that central-cell radial nonambipolar confinement scales as neoclassical theory and can be eliminated by floating the end walls. Radial ambipolar losses can also be measured and reduced. The electron energy balance is improved in tandem mirrors to near classical, resulting in T/sub e/ up to 0.28 keV. Electron cyclotron heating (ECH) efficiencies up to 42 percent, with low levels of electron microinstability, were achieved when hot electrons in the thermal barrier were heated to average betas as large as 15 percent. The hot-electron distribution is measured from X rays and is modeled by a Fokker-Planck code that includes heating from cavity radio-frequency (RF) fields. Neutral-beam injection in the central cell created average ion betas up to 5 percent with radial profiles of hot ions that are modeled accurately by a radial Fokker-Planck code. Gas fueling between two fundamental ion cyclotron heating (ICH) resonances resulted in symmetrical heating of passing ions toward both ends.

Simonen, T.C.; Allen, S.L.; Barter, J.D.; Casper, T.A.; Correll, D.L.; Carter, M.R.; Clauser, J.F.; Dimonte, G.; Foote, J.H.; Futch, A.H.

1988-02-01T23:59:59.000Z

391

High-brightness electron beam evolution following laser-based cleaning of a photocathode  

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

Laser-based techniques have been widely used for cleaning metal photocathodes to increase quantum efficiency (QE). However, the impact of laser cleaning on cathode uniformity and thereby on electron beam quality are less understood. We are evaluating whether this technique can be applied to revive photocathodes used for high-brightness electron sources in advanced x-ray free-electron laser (FEL) facilities, such as the Linac Coherent Light Source (LCLS) at the SLAC National Accelerator Laboratory. The laser-based cleaning was applied to two separate areas of the current LCLS photocathode on July 4 and July 26, 2011, respectively. The QE was increased by 810 times upon the laser cleaning. Since the cleaning, routine operation has exhibited a slow evolution of the QE improvement and comparatively rapid improvement of transverse emittance, with a factor of 3 QE enhancement over five months, and a significant emittance improvement over the initial 23 weeks following the cleaning. Currently, the QE of the LCLS photocathode is holding constant at about 1.210?4 , with a normalized injector emittance of about 0.3???m for a 150-pC bunch charge. With the proper procedures, the laser-cleaning technique appears to be a viable tool to revive the LCLS photocathode. We present observations and analyses for the QE and emittance evolution in time following the laser-based cleaning of the LCLS photocathode, and comparison to the previous studies, the measured thermal emittance versus the QE and comparison to the theoretical model.

Zhou, F.; Brachmann, A.; Decker, F-J.; Emma, P.; Gilevich, S.; Iverson, R.; Stefan, P.; Turner, J.

2012-09-01T23:59:59.000Z

392

Thermal plasmonic interconnects in graphene  

Science Journals Connector (OSTI)

As one emerging plasmonic material, graphene can support surface plasmons at infrared and terahertz frequencies with unprecedented properties due to the strong interactions between graphene and low-frequency photons. Since graphene surface plasmons exist in the infrared and terahertz regime, they can be thermally pumped (excited) by the infrared evanescent waves emitted from an object. Here we show that thermal graphene plasmons can be efficiently excited and have monochromatic and tunable spectra, thus paving a way to harness thermal energy for graphene plasmonic devices. We further demonstrate that thermal information communication via graphene surface plasmons can be potentially realized by effectively harnessing thermal energy from various heat sources, e.g., the waste heat dissipated from nanoelectronic devices. These findings open up an avenue of thermal plasmonics based on graphene for different applications ranging from infrared emission control, to information processing and communication, to energy harvesting.

Baoan Liu; Yongmin Liu; Sheng Shen

2014-11-10T23:59:59.000Z

393

Sandia National Laboratories: Improved Method to Measure Glare...  

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

to Measure Glare and Reflected Solar Irradiance On February 27, 2013, in Concentrating Solar Power, Energy, Facilities, National Solar Thermal Test Facility, News, News &...

394

Thermal desorption for passive dosimeter  

E-Print Network [OSTI]

~ ~ ~ \\ ~ ~ ~ ~ Flare Tubes for Thermal Desorber . . . . . ~. . . . . . ~ ~ . 27 4. 5 ~ Thermal Desorber Manufactured by Century System Sample Flow from Thermal Desorber to Gas Chromatograph 29 6. Direct Injection Port for Therma1 Desorber . . . . . $2... the gas badges and. providing additional guidance in conducting the study. DEDICATZOil This thesis is cedicated to my parents and my wife, Unice, for their support during the last t', o years AHSTHACT ACKI;ODL DG~~. 'ITS D' DICATICI'. LIST OF TABL...

Liu, Wen-Chen

1981-01-01T23:59:59.000Z

395

Actively driven thermal radiation shield  

DOE Patents [OSTI]

A thermal radiation shield for cooled portable gamma-ray spectrometers. The thermal radiation shield is located intermediate the vacuum enclosure and detector enclosure, is actively driven, and is useful in reducing the heat load to mechanical cooler and additionally extends the lifetime of the mechanical cooler. The thermal shield is electrically-powered and is particularly useful for portable solid-state gamma-ray detectors or spectrometers that dramatically reduces the cooling power requirements. For example, the operating shield at 260K (40K below room temperature) will decrease the thermal radiation load to the detector by 50%, which makes possible portable battery operation for a mechanically cooled Ge spectrometer.

Madden, Norman W. (Livermore, CA); Cork, Christopher P. (Pleasant Hill, CA); Becker, John A. (Alameda, CA); Knapp, David A. (Livermore, CA)

2002-01-01T23:59:59.000Z

396

Enhanced Thermal Conductivity Oxide Fuels  

SciTech Connect (OSTI)

the purpose of this project was to investigate the feasibility of increasing the thermal conductivity of oxide fuels by adding small fractions of a high conductivity solid phase.

Alvin Solomon; Shripad Revankar; J. Kevin McCoy

2006-01-17T23:59:59.000Z

397

Measuring Cosmological Distances Scale Factor Evolution: a(t)  

E-Print Network [OSTI]

" Model : CDM 0 = 71, m = 0.27 = 0.73 #12;Dark Matter in the 1840s: Neptune Discovery Uranus orbit #12;#12;#12;#12;#12;#12;Equation of State of Dark Energy: w w ~ P/ #12;) Mass-Energy = Curvature Spacetime (1/a2) d2a/dt2 = -4/3G ( + 3P/c2) + c2/3 #12;Derivation: Critical

Shirley, Yancy

398

VarPetrRef 1 VARIETY AND THE EVOLUTION OF REFINERY PROCESSING  

E-Print Network [OSTI]

VarPetrRef 1 VARIETY AND THE EVOLUTION OF REFINERY PROCESSING Phuong NGUYEN*, Pier-Paolo SAVIOTTI, refinery processes, variety, niche theory, Weitzman measure. JEL classification : L15 -L93 -O3 1

Paris-Sud XI, Université de

399

Time evolution of entangled biatomic states in a cavity  

SciTech Connect (OSTI)

We study the time evolution of entangled states of a pair of identical atoms, considered in the harmonic approximation, coupled to an environment represented by an infinite set of free oscillators, with the whole system confined within a spherical cavity of radius R. Taking the center-of-mass and the relative-position coordinates, and using the dressed-state approach, we present the time evolution of some quantities measuring the entanglement for both limits of a very large and a small cavity; the chosen examples are simple and illustrate these very distinct behaviors.

Figueiredo, E. G. [Instituto de Fisica, Universidade Federal da Bahia, 40210-340, Salvador, BA (Brazil); Centro de Cie circumflex ncias Exatas e Tecnologicas, Universidade Federal do Reco circumflex ncavo da Bahia, 44380-000, Cruz das Almas, BA (Brazil); Linhares, C. A. [Instituto de Fisica, Universidade do Estado do Rio de Janeiro, 20559-900, Rio de Janeiro, RJ (Brazil); Malbouisson, A. P. C. [Centro Brasileiro de Pesquisas Fisicas/MCT, 22290-180, Rio de Janeiro, RJ (Brazil); Malbouisson, J. M. C. [Instituto de Fisica, Universidade Federal da Bahia, 40210-340, Salvador, BA (Brazil)

2011-10-15T23:59:59.000Z

400

Underground Coal Thermal Treatment  

SciTech Connect (OSTI)

The long-term objective of this work is to develop a transformational energy production technology by insitu thermal treatment of a coal seam for the production of substitute natural gas (SNG) while leaving much of the coal??s carbon in the ground. This process converts coal to a high-efficiency, low-GHG emitting gas fuel. It holds the potential of providing environmentally acceptable access to previously unusable coal resources. This topical report discusses the development of experimental capabilities, the collection of available data, and the development of simulation tools to obtain process thermo-chemical and geo-thermal parameters in preparation for the eventual demonstration in a coal seam. It also includes experimental and modeling studies of CO{sub 2} sequestration. Efforts focused on: ? Constructing a suite of three different coal pyrolysis reactors. These reactors offer the ability to gather heat transfer, mass transfer and kinetic data during coal pyrolysis under conditions that mimic in situ conditions (Subtask 6.1). ? Studying the operational parameters for various underground thermal treatment processes for oil shale and coal and completing a design matrix analysis for the underground coal thermal treatment (UCTT). This analysis yielded recommendations for terms of targeted coal rank, well orientation, rubblization, presence of oxygen, temperature, pressure, and heating sources (Subtask 6.2). ? Developing capabilities for simulating UCTT, including modifying the geometry as well as the solution algorithm to achieve long simulation times in a rubblized coal bed by resolving the convective channels occurring in the representative domain (Subtask 6.3). ? Studying the reactive behavior of carbon dioxide (CO{sub 2}) with limestone, sandstone, arkose (a more complex sandstone) and peridotite, including mineralogical changes and brine chemistry for the different initial rock compositions (Subtask 6.4). Arkose exhibited the highest tendency of participating in mineral reactions, which can be attributed to the geochemical complexity of its initial mineral assemblage. In experiments with limestone, continuous dissolution was observed with the release of CO{sub 2} gas, indicated by the increasing pressure in the reactor (formation of a gas chamber). This occurred due to the lack of any source of alkali to buffer the solution. Arkose has the geochemical complexity for permanent sequestration of CO{sub 2} as carbonates and is also relatively abundant. The effect of including NH{sub 3} in the injected gas stream was also investigated in this study. Precipitation of calcite and trace amounts of ammonium zeolites was observed. A batch geochemical model was developed using Geochemists Workbench (GWB). Degassing effect in the experiments was corrected using the sliding fugacity model in GWB. Experimental and simulation results were compared and a reasonable agreement between the two was observed.

P. Smith; M. Deo; E. Eddings; A. Sarofim; K. Gueishen; M. Hradisky; K. Kelly; P. Mandalaparty; H. Zhang

2011-10-30T23:59:59.000Z

Note: This page contains sample records for the topic "measuring thermal evolution" 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

Thermally induced photon splitting  

E-Print Network [OSTI]

We calculate thermal corrections to the non-linear QED effective action for low-energy photon interactions in a background electromagnetic field. The high-temperature expansion shows that at $T \\gg m$ the vacuum contribution is exactly cancelled to all orders in the external field except for a non-trivial two-point function contribution. The high-temperature expansion derived reveals a remarkable cancellation of infrared sensitive contributions. As a result photon-splitting in the presence of a magnetic field is suppressed in the presence of an electron-positron QED-plasma at very high temperatures. In a cold and dense plasma a similar suppression takes place. At the same time Compton scattering dominates for weak fields and the suppression is rarely important in physical situations.

Per Elmfors; Bo-Sture Skagerstam

1998-02-23T23:59:59.000Z

402

Thermal barrier coatings  

DOE Patents [OSTI]

This disclosure addresses the issue of providing a metallic-ceramic overlay coating that potentially serves as an interface or bond coat layer to provide enhanced oxidation resistance to the underlying superalloy substrate via the formation of a diffusion barrier regime within the supporting base material. Furthermore, the metallic-ceramic coating is expected to limit the growth of a continuous thermally grown oxide (TGO) layer that has been primarily considered to be the principal cause for failure of existing TBC systems. Compositional compatibility of the metallic-ceramic with traditional yttria-stabilized zirconia (YSZ) top coats is provided to further limit debond or spallation of the coating during operational use. A metallic-ceramic architecture is disclosed wherein enhanced oxidation resistance is imparted to the surface of nickel-based superalloy or single crystal metal substrate, with simultaneous integration of the yttria stabilized zirconia (YSZ) within the metallic-ceramic overlayer.

Alvin, Mary Anne (Pittsburg, PA)

2010-06-22T23:59:59.000Z

403

Phase Change Materials for Thermal Energy Storage in Concentrated Solar Thermal Power Plants  

E-Print Network [OSTI]

OF CALIFORNIA RIVERSIDE Phase Change Materials for ThermalOF THE THESIS Phase Change Materials for Thermal Energyto utilize phase change materials (PCMs) to enhance thermal

Hardin, Corey Lee

2011-01-01T23:59:59.000Z

404

Phase Change Materials for Thermal Energy Storage in Concentrated Solar Thermal Power Plants  

E-Print Network [OSTI]

PHASE CHANGE THERMAL ENERGY STORAGE FOR CONCENTRATING SOLARChange Materials for Thermal Energy Storage in ConcentratedChange Materials for Thermal Energy Storage in Concentrated

Hardin, Corey Lee

2011-01-01T23:59:59.000Z

405

NUMERICAL, EXPERIMENTAL AND ANALYTICAL STUDY OF THERMAL HEATING OF SPHERE AND DISK SHAPED BIOCRYSTALS EXPOSED TO 3 RDGENERATION SYNCHROTON SOURCES.  

E-Print Network [OSTI]

??The thesis is broadly divided into three major parts. In the first part, thermal imaging is used to experimentally measure temperature and a numerical model (more)

SAMPATH KUMAR, RAGHAV

2006-01-01T23:59:59.000Z

406

Thermal-Hydrological Sensitivity Analysis of Underground Coal Gasification  

SciTech Connect (OSTI)

This paper presents recent work from an ongoing project at Lawrence Livermore National Laboratory (LLNL) to develop a set of predictive tools for cavity/combustion-zone growth and to gain quantitative understanding of the processes and conditions (natural and engineered) affecting underground coal gasification (UCG). We discuss the application of coupled thermal-hydrologic simulation capabilities required for predicting UCG cavity growth, as well as for predicting potential environmental consequences of UCG operations. Simulation of UCG cavity evolution involves coupled thermal-hydrological-chemical-mechanical (THCM) processes in the host coal and adjoining rockmass (cap and bedrock). To represent these processes, the NUFT (Nonisothermal Unsaturated-saturated Flow and Transport) code is being customized to address the influence of coal combustion on the heating of the host coal and adjoining rock mass, and the resulting thermal-hydrological response in the host coal/rock. As described in a companion paper (Morris et al. 2009), the ability to model the influence of mechanical processes (spallation and cavity collapse) on UCG cavity evolution is being developed at LLNL with the use of the LDEC (Livermore Distinct Element Code) code. A methodology is also being developed (Morris et al. 2009) to interface the results of the NUFT and LDEC codes to simulate the interaction of mechanical and thermal-hydrological behavior in the host coal/rock, which influences UCG cavity growth. Conditions in the UCG cavity and combustion zone are strongly influenced by water influx, which is controlled by permeability of the host coal/rock and the difference between hydrostatic and cavity pressure. In this paper, we focus on thermal-hydrological processes, examining the relationship between combustion-driven heat generation, convective and conductive heat flow, and water influx, and examine how the thermal and hydrologic properties of the host coal/rock influence those relationships. Specifically, we conducted a parameter sensitivity analysis of the influence of thermal and hydrological properties of the host coal, caprock, and bedrock on cavity temperature and steam production.

Buscheck, T A; Hao, Y; Morris, J P; Burton, E A

2009-10-05T23:59:59.000Z

407

Thermal effects on the stability of excited atoms in cavities  

SciTech Connect (OSTI)

An atom, coupled linearly to an environment, is considered in a harmonic approximation in thermal equilibrium inside a cavity. The environment is modeled by an infinite set of harmonic oscillators. We employ the notion of dressed states to investigate the time evolution of the atom initially in the first excited level. In a very large cavity (free space) for a long elapsed time, the atom decays and the value of its occupation number is the physically expected one at a given temperature. For a small cavity the excited atom never completely decays and the stability rate depends on temperature.

Khanna, F. C.; Malbouisson, A. P. C.; Malbouisson, J. M. C.; Santana, A. E. [Department of Physics, University of Alberta, Edmonton, Alberta T6G 2J1 (Canada) and TRIUMF, Vancouver, British Columbia V6T 2A3 (Canada); Centro Brasileiro de Pesquisas Fisicas/MCT, 22290-180 Rio de Janeiro, Rio de Janeiro (Brazil); Instituto de Fisica, Universidade Federal da Bahia, 40.210-310 Salvador, Bahia (Brazil); Instituto de Fisica, Universidade de Brasilia, 70910-900 Brasilia, Distrito Federal (Brazil) and Department of Physics, University of Alberta, Edmonton, Alberta T6G 2J1 (Canada)

2010-03-15T23:59:59.000Z

408

Peg supported thermal insulation panel  

DOE Patents [OSTI]

A thermal insulation panel which is lightweight, load bearing, accommodates thermal stress, and has excellent high temperature insulation capability comprises high performance insulation between thin metal walls supported by high density, high strength glass pegs made in compliance with specified conditions of time, temperature and pressure. 2 figs.

Nowobilski, J.J.; Owens, W.J.

1985-04-30T23:59:59.000Z

409

Peg supported thermal insulation panel  

DOE Patents [OSTI]

A thermal insulation panel which is lightweight, load bearing, accommodates thermal stress, and has excellent high temperature insulation capability comprising high performance insulation between thin metal walls supported by high density, high strength glass pegs made in compliance with specified conditions of time, temperature and pressure.

Nowobilski, Jeffert J. (Orchard Park, NY); Owens, William J. (Kenmore, NY)

1985-01-01T23:59:59.000Z

410

Influence of nano-ZrO2 on the mechanical and thermal properties of high temperature cementitious thermal energy storage materials  

Science Journals Connector (OSTI)

Abstract The mechanical and thermal properties of high temperature aluminate cementitious thermal energy storage materials modified with nano-ZrO2 are investigated. The influence of nano-ZrO2 amounts on the performance, such as compressive strength, thermal conductivity, volume heat capacity, and thermal expansion coefficient, of hardened composite cement pastes were studied for future solar thermal energy materials with better performance. It is observed that before heating the pore structure and compressive strength are both optimized at the optimum nano-ZrO2 amount of 1wt%. At the same time, thermal conductivity and volume heat capacity of the composite paste enriched with nano-ZrO2 improved after heating at 350 and 900C compared with that of pure paste, which is very favorable for high thermal storage materials application. XRD, TGDSC, FTIR, and MIP were used to characterize the mineral phases, the hydration/dehydration evolution, the chemical bonding, and the pore structures of the hydration products, respectively.

Huiwen Yuan; Yu Shi; Zhongzi Xu; Chunhua Lu; Yaru Ni; Xianghui Lan

2013-01-01T23:59:59.000Z

411

Heat Loss Measurement Using Infrared Imaging  

E-Print Network [OSTI]

in various applications. Examples of two applications are presented. The first describes the development of heat balance data for a solvent refined coal processing unit. The second describes the measurement of heat loss and thermal resistance in a double...

Seeber, S. A.

1983-01-01T23:59:59.000Z

412

Geochemical Sampling of Thermal Waters in Nevada | Open Energy Information  

Open Energy Info (EERE)

Geochemical Sampling of Thermal Waters in Nevada Geochemical Sampling of Thermal Waters in Nevada Jump to: navigation, search OpenEI Reference LibraryAdd to library Conference Paper: Geochemical Sampling of Thermal Waters in Nevada Abstract There are 1000 thermal springs in Nevada for which a location is known, but for which there are no available temperature (or chemical) measurements. Although many of these sites are within known geothermal areas and are located near springs for which temperature and/or geochemical data are available for one of the springs, many of these sites are not so located and require evaluation before the geothermal potential of the area can be assessed. In order to begin filling in data gaps, water sampling commenced in 2002 when over 70 analyses were obtained from springs with previously

413

Thermal Conductivity and Noise Attenuation in  

E-Print Network [OSTI]

.3.4 Corrosion-resistant and high-temperature filters 9 1.3.5 Acoustic Applications 9 2. THERMAL CONDUCTIVITY 2.1 THERMAL RESISTANCE 2.1.1 Thermal Conductors in Series 12 2.1.2 Thermal conductors in parallel 13 2 difference RTH Thermal resistance of conductor sb Stefan's constant T4 Temperature difference K* Total

Cambridge, University of

414

Nanoscale Thermal Transport andMicrorefrigeratorsonaChip  

E-Print Network [OSTI]

are promising candidates as thermal vias and thermal interface materials due to their inherently high thermal; superlattices; thermal boundary resistance; thermionics; thermotunneling; thermoelectrics I. INTRODUCTIONINVITED P A P E R Nanoscale Thermal Transport andMicrorefrigeratorsonaChip Devices for cooling high

415

MODELING THE RED SEQUENCE: HIERARCHICAL GROWTH YET SLOW LUMINOSITY EVOLUTION  

SciTech Connect (OSTI)

We explore the effects of mergers on the evolution of massive early-type galaxies by modeling the evolution of their stellar populations in a hierarchical context. We investigate how a realistic red sequence population set up by z {approx} 1 evolves under different assumptions for the merger and star formation histories, comparing changes in color, luminosity, and mass. The purely passive fading of existing red sequence galaxies, with no further mergers or star formation, results in dramatic changes at the bright end of the luminosity function and color-magnitude relation. Without mergers there is too much evolution in luminosity at a fixed space density compared to observations. The change in color and magnitude at a fixed mass resembles that of a passively evolving population that formed relatively recently, at z {approx} 2. Mergers among the red sequence population ('dry mergers') occurring after z = 1 build up mass, counteracting the fading of the existing stellar populations to give smaller changes in both color and luminosity for massive galaxies. By allowing some galaxies to migrate from the blue cloud onto the red sequence after z = 1 through gas-rich mergers, younger stellar populations are added to the red sequence. This manifestation of the progenitor bias increases the scatter in age and results in even smaller changes in color and luminosity between z = 1 and z = 0 at a fixed mass. The resultant evolution appears much slower, resembling the passive evolution of a population that formed at high redshift (z {approx} 3-5), and is in closer agreement with observations. We conclude that measurements of the luminosity and color evolution alone are not sufficient to distinguish between the purely passive evolution of an old population and cosmologically motivated hierarchical growth, although these scenarios have very different implications for the mass growth of early-type galaxies over the last half of cosmic history.

Skelton, Rosalind E. [Department of Astronomy, Yale University, 260 Whitney Avenue, New Haven, CT 06511 (United States); Bell, Eric F. [Department of Astronomy, University of Michigan, 500 Church Street, Ann Arbor, MI 48109-1042 (United States); Somerville, Rachel S., E-mail: ros.skelton@yale.edu [Department of Physics and Astronomy, Rutgers, State University of New Jersey, 136 Frelinghuysen Road, Piscataway, NJ 08854 (United States)

2012-07-01T23:59:59.000Z

416

Thermal Conductivity of Thermally-Isolating Polymeric and Composite Structural Support Materials Between 0.3 and 4 K  

E-Print Network [OSTI]

We present measurements of the low-temperature thermal conductivity of a number of polymeric and composite materials from 0.3 to 4 K. The materials measured are Vespel SP-1, Vespel SP-22, unfilled PEEK, 30% carbon fiber-filled PEEK, 30% glass-filled PEEK, carbon fiber Graphlite composite rod, Torlon 4301, G-10/FR-4 fiberglass, pultruded fiberglass composite, Macor ceramic, and graphite rod. These materials have moderate to high elastic moduli making them useful for thermally-isolating structural supports.

M. C. Runyan; W. C. Jones

2008-06-11T23:59:59.000Z

417

Thermal Conductivity of Thermally-Isolating Polymeric and Composite Structural Support Materials Between 0.3 and 4 K  

E-Print Network [OSTI]

We present measurements of the low-temperature thermal conductivity of a number of polymeric and composite materials from 0.3 to 4 K. The materials measured are Vespel SP-1, Vespel SP-22, unfilled PEEK, 30% carbon fiber-filled PEEK, 30% glass-filled PEEK, carbon fiber Graphlite composite rod, Torlon 4301, G-10/FR-4 fiberglass, pultruded fiberglass composite, Macor ceramic, and graphite rod. These materials have moderate to high elastic moduli making them useful for thermally-isolating structural supports.

Runyan, M C

2008-01-01T23:59:59.000Z

418

Missing Thermal Energy of the Intracluster Medium  

E-Print Network [OSTI]

The Sunyaev-Zel'dovich (SZ) effect is a direct probe of thermal energy content of the Universe, induced in the cosmic microwave background (CMB) sky through scattering of CMB photons off hot electrons in the intracluster medium (ICM). We report a 9-sigma detection of the SZ signal in the CMB maps of Wilkinson Microwave Anisotropy Probe (WMAP) 3yr data, through study of a sample of 193 massive galaxy clusters with observed X-ray temperatures greater than 3 keV. For the first time, we make a model-independent measurement of the pressure profile in the outskirts of the ICM, and show that it closely follows the profiles obtained by X-ray observations and numerical simulations. We find that our measurements of the SZ effect would account for only half of the thermal energy of the cluster, if all the cluster baryons were in the hot ICM phase. Our measurements indicate that a significant fraction (35 +/- 8 %) of baryonic mass is missing from the hot ICM, and thus must have cooled to form galaxies, intracluster stars, or an unknown cold phase of the ICM. There does not seem to be enough mass in the form of stars or cold gas in the cluster galaxies or intracluster space, signaling the need for a yet-unknown baryonic component (at 3-sigma level), or otherwise new astrophysical processes in the ICM.

Niayesh Afshordi; Yen-Ting Lin; Daisuke Nagai; Alastair J. R. Sanderson

2006-12-26T23:59:59.000Z

419

Study on thermal performance of high power LED employing aluminum filled epoxy composite as thermal interface material  

Science Journals Connector (OSTI)

Abstract This paper elucidates the thermal behavior of an LED employing metal filled polymer matrix as thermal interface material (TIM) for an enhanced heat dissipation characteristic. Highly thermal conductive aluminum (Al) particles were incorporated in bisphenol A diglycidylether (DGEBA) epoxy matrix to study the effect of filler to polymer ratio on the thermal performance of high power LEDs. The curing behavior of DGEBA was studied by differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA). The dispersion nature of the Al fillers in polymer matrix was verified with Field Emission Scanning Electron Microscope (FESEM). The thermal performance of synthesized Al filled polymer composite as TIM was tested with an LED employing thermal transient measurement technique. Comparing the filler to polymer ratio, the rise in junction temperature for 60wt% Al filled composite was higher by 11.1C than 50wt% Al filled composite at cured state. Observed also from the structure function analysis that the total thermal resistance was 10.96K/W higher for 60wt% Al filled composite compared to 50wt% Al filled composite. On the other hand, a significant rise of 9.5C in the junction temperature between cured and uncured samples of 50wt% Al filled polymer TIM was observed and hence the importance of curing process of metal filled polymer composite for effective heat dissipation is discussed extensively in this work.

P. Anithambigai; S. Shanmugan; D. Mutharasu; T. Zahner; D. Lacey

2014-01-01T23:59:59.000Z

420

MINIMIZING THE BONDLINE THERMAL RESISTANCE IN THERMAL INTERFACE MATERIALS WITHOUT AFFECTING RELIABILITY  

E-Print Network [OSTI]

MINIMIZING THE BONDLINE THERMAL RESISTANCE IN THERMAL INTERFACE MATERIALS WITHOUT AFFECTING microstructure, and bondline thermal resistance with the tradeoffs between material systems, manufacturability of devices to heat sinks using existing commercial thermal interface materials (TIMs). The present study

Paris-Sud XI, Université de

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


421

Universality and Evolution of TMDs  

E-Print Network [OSTI]

In this talk, we summarize how QCD evolution can be exploited to improve the treatment of transverse momentum dependent (TMD) parton distribution and fragmentation functions. The methods allow existing non-perturbative fits to be turned into fully evolved TMDs that are consistent with a complete TMD-factorization formalism over the full range of kT. We argue that evolution is essential to the predictive power of calculations that utilize TMD parton distribution and fragmentation functions, especially TMD observables that are sensitive to transverse spin.

S. Mert Aybat; Ted C. Rogers

2011-10-27T23:59:59.000Z

422

A heavy oil thermal cracking simulation program  

SciTech Connect (OSTI)

Correlations were developed to simulate the thermal cracking reaction of petroleum vacuum distillation residues through pilot plant data analysis. They use charge properties like specific gravity, viscosity, sulphur content and initial boiling point to give the yield and quality of products as a function of conversion, which is measured in terms of wt.% products with normal boiling point below 350{degrees}C. The mixture is represented with 24 lumps, and kinetic parameters for the reaction feed {r_arrow} products were also found as a function of feedstock properties. Finally, a computer program was developed to simulate fired heater operation for visbreaking and delayed coking units. 3 refs., 10 figs., 1 tab.

Maciel, R. [UNICAMP, Campinas (Brazil); Sugaya, M.F. [Petrobrais, Rio de Janeiro (Brazil)

1996-12-31T23:59:59.000Z

423

Thermal to electricity conversion using thermal magnetic properties  

DOE Patents [OSTI]

A system for the generation of Electricity from Thermal Energy using the thermal magnetic properties of a Ferromagnetic, Electrically Conductive Material (FECM) in one or more Magnetic Fields. A FECM is exposed to one or more Magnetic Fields. Thermal Energy is applied to a portion of the FECM heating the FECM above its Curie Point. The FECM, now partially paramagnetic, moves under the force of the one or more Magnetic Fields. The movement of the FECM induces an electrical current through the FECM, generating Electricity.

West, Phillip B [Idaho Falls, ID; Svoboda, John [Idaho Falls, ID

2010-04-27T23:59:59.000Z

424

Generating random thermal momenta  

E-Print Network [OSTI]

Generation of random thermal particle momenta is a basic task in many problems, such as microscopic studies of equilibrium and transport properties of systems, or the conversion of a fluid to particles. In heavy-ion physics, the (in)efficiency of the algorithm matters particularly in hybrid hydrodynamics + hadronic transport calculations. With popular software packages, such as UrQMD 3.3p1 or THERMINATOR, it can still take ten hours to generate particles for a single Pb+Pb "event" at the LHC from fluid dynamics output. Below I describe reasonably efficient simple algorithms using the MPC package, which should help speed momentum generation up by at least one order of magnitude. It is likely that this wheel has been reinvented many times instead of reuse, so there may very well exist older and/or better algorithms that I am not aware of (MPC has been around only since 2000). The main goal here is to encourage practitioners to use available efficient routines, and offer a few practical solutions.

Denes Molnar

2012-12-09T23:59:59.000Z

425

Microelectromechanical (MEM) thermal actuator  

DOE Patents [OSTI]

Microelectromechanical (MEM) buckling beam thermal actuators are disclosed wherein the buckling direction of a beam is constrained to a desired direction of actuation, which can be in-plane or out-of-plane with respect to a support substrate. The actuators comprise as-fabricated, linear beams of uniform cross section supported above the substrate by supports which rigidly attach a beam to the substrate. The beams can be heated by methods including the passage of an electrical current through them. The buckling direction of an initially straight beam upon heating and expansion is controlled by incorporating one or more directional constraints attached to the substrate and proximal to the mid-point of the beam. In the event that the beam initially buckles in an undesired direction, deformation of the beam induced by contact with a directional constraint generates an opposing force to re-direct the buckling beam into the desired direction. The displacement and force generated by the movement of the buckling beam can be harnessed to perform useful work, such as closing contacts in an electrical switch.

Garcia, Ernest J. (Albuquerque, NM); Fulcher, Clay W. G. (Sandia Park, NM)

2012-07-31T23:59:59.000Z

426

Measurement and modeling thermal conductivity of baked products  

E-Print Network [OSTI]

the intercept with the y-sxis (dp) and the error term (e), and adds variables one at a time until a. stopping criterion is satisfied, 0. 1 6 Q 0. 14 8 3 0. 12 g 0. 10 O V 0. 08 0. 06 + + + +y++++ ++ ~ +est~ ~ 4. + ~ c ~ + ~ f ~f, ?, , ey ~ ~ p... FOR DEPENDENT VARIABLE K STATISTICS FOR ENTRY: STEP 1 DF 1. 80 MODEL VARIABLE TOLERANCE R* 2 F PROB&F W 0 POR 1 0. 0373 3. 0995 1 0. 2539 27. 2194 1 0. 0099 0. 8006 0. 0821 0. 0001 0. 3736 STEP 1 VARIABLE D ENTERED R SQUARE = 0. 25386619 C(P) = 2...

Islas Rubio, Alma Rosa

2012-06-07T23:59:59.000Z

427

Measurement of Thermal Neutron Flux in Photo-Neutron Source  

Science Journals Connector (OSTI)

The Photo-Neutron Source (PNS) project is a study ... design, simulation and construction an accelerator based neutron source for Boron Neutron Capture Therapy (BNCT). The system uses ... medical linear accelerat...

A. Taheri; A. Torkamani; A. Pazirandeh

2013-01-01T23:59:59.000Z

428

Measure of Diffusion Model Error for Thermal Radiation Transport  

E-Print Network [OSTI]

cm2 sh keV c Speed of light 2:99 102 cmsh D Di usion coe cient ( 13 t ) cm F Radiation ux jkcm2 sh k Time iteration t Di erence between consecutive time steps shakes(sh) hi Size of spatial cell, i cm ! Direction of photon propagation ster... backward Euler implicit di erencing in time and lumped LD in space to (5.5), we get 1 c t (k+ 12) i;L (k 12) i;L hi 2 + F (k+ 12) i F (k+ 12) i 12 + hi 2 a (k+ 12) i;L = QL hi 2 ; (8.2a) 1 c t (k+ 12) i;R (k...

Kumar, Akansha

2013-04-19T23:59:59.000Z

429

THERMAL PERFORMANCE MEASUREMENTS ON ULTIMATE HEAT SINKS - COOLING...  

Office of Scientific and Technical Information (OSTI)

total down and net radiation are sub- stantially affected by the state of the sky in terms of cloudi- ness. The data volume contains both sets of data and also, in this Chapter,...

430

Measurements of molecular and thermal diffusion coefficients in ternary mixtures  

E-Print Network [OSTI]

of a polymer and a colloid in a water-ethanol solvent, treating the ternary mixture as a pseudobinary; Gans et polymer in a water-ethanol solvent mixture. They reported a sign change in the Soret coefficient

Firoozabadi, Abbas

431

THERMAL ENERGY STORAGE IN AQUIFERS WORKSHOP  

E-Print Network [OSTI]

and J. Schwarz, Survey of Thermal Energy Storage in AquifersLow Temperature Thermal Energy Storage Program of Oak RidgeAquifers for Seasonal Thermal Energy Storage: An Overview of

Authors, Various

2011-01-01T23:59:59.000Z

432

Advanced nanofabrication of thermal emission devices  

E-Print Network [OSTI]

Nanofabricated thermal emission devices can be used to modify and modulate blackbody thermal radiation. There are many areas in which altering thermal radiation is extremely useful, especially in static power conversion, ...

Hurley, Fergus (Fergus Gerard)

2008-01-01T23:59:59.000Z

433

Ceramic thermal barrier coating for rapid thermal cycling applications  

DOE Patents [OSTI]

A thermal barrier coating for metal articles subjected to rapid thermal cycling includes a metallic bond coat deposited on the metal article, at least one MCrAlY/ceramic layer deposited on the bond coat, and a ceramic top layer deposited on the MCrAlY/ceramic layer. The M in the MCrAlY material is Fe, Ni, Co, or a mixture of Ni and Co. The ceramic in the MCrAlY/ceramic layer is mullite or Al.sub.2 O.sub.3. The ceramic top layer includes a ceramic with a coefficient of thermal expansion less than about 5.4.times.10.sup.-6 .degree.C.sup.-1 and a thermal conductivity between about 1 J sec.sup.-1 m.sup.-1 .degree.C.sup.-1 and about 1.7 J sec.sup.-1 m.sup.-1 .degree.C.sup.-1.

Scharman, Alan J. (Hebron, CT); Yonushonis, Thomas M. (Columbus, IN)

1994-01-01T23:59:59.000Z

434

Recycling of wasted energy : thermal to electrical energy conversion  

E-Print Network [OSTI]

heat source can be solar thermal energy, biological thermaland concentrated solar thermal energy farms. They demandsources include solar thermal energy, geo-thermal energy,

Lim, Hyuck

2011-01-01T23:59:59.000Z

435

Thermoelectrics Combined with Solar Concentration for Electrical and Thermal Cogeneration  

E-Print Network [OSTI]

significant challenge for solar thermal energy generation issolar thermal, cogeneration of electrical and thermal energy,for efficient energy production. Solar thermal plants, such

Jackson, Philip Robert

2012-01-01T23:59:59.000Z

436

Determination of heat conductivity and thermal diffusivity of waste glass melter feed: Extension to high temperatures  

SciTech Connect (OSTI)

The heat conductivity ({lambda}) and the thermal diffusivity (a) of reacting glass batch, or melter feed, control the heat flux into and within the cold cap, a layer of reacting material floating on the pool of molten glass in an all-electric continuous waste glass melter. After previously estimating {lambda} of melter feed at temperatures up to 680 deg C, we focus in this work on the {lambda}(T) function at T > 680 deg C, at which the feed material becomes foamy. We used a customized experimental setup consisting of a large cylindrical crucible with an assembly of thermocouples, which monitored the evolution of the temperature field while the crucible with feed was heated at a constant rate from room temperature up to 1100C. Approximating measured temperature profiles by polynomial functions, we used the heat transfer equation to estimate the {lambda}(T) approximation function, which we subsequently optimized using the finite-volume method combined with least-squares analysis. The heat conductivity increased as the temperature increased until the feed began to expand into foam, at which point the conductivity dropped. It began to increase again as the foam turned into a bubble-free glass melt. We discuss the implications of this behavior for the mathematical modeling of the cold cap.

Rice, Jarrett A.; Pokorny, Richard; Schweiger, Michael J.; Hrma, Pavel R.

2014-05-12T23:59:59.000Z

437

Thermal Conversion Process (TCP) Technology  

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

Changing World Technologies' Changing World Technologies' Thermal Conversion Process Commercial Demonstration Plant DOE/EA 1506 Weld County, Colorado December 2004 U.S. DEPARTMENT OF ENERGY GOLDEN FIELD OFFICE 1617 Cole Boulevard Golden, Colorado 80401 Thermal Conversion Process (TCP) Technology Commercial Demonstration - Weld County, CO TABLE OF CONTENTS Environmental Assessment Thermal Conversion Process (TCP) Technology Commercial Demonstration Project Weld County, Colorado SUMMARY............................................................................................................................. S-1 1.0 INTRODUCTION.........................................................................................................1-1 1.1. National Environmental Policy Act and Related Procedures...........................1-1

438

VIRAL EVOLUTION Genomic surveillance elucidates  

E-Print Network [OSTI]

VIRAL EVOLUTION Genomic surveillance elucidates Ebola virus origin and transmission during the 2014,12,13 � Robert F. Garry,8 � S. Humarr Khan,3 � Pardis C. Sabeti1,2 � In its largest outbreak, Ebola virus disease is spreading through Guinea, Liberia, Sierra Leone, and Nigeria. We sequenced 99 Ebola virus genomes from 78

Napp, Nils

439

Convergent evolution of protein structure  

E-Print Network [OSTI]

Convergent evolution of protein structure prediction and computer chess tournaments: CASP, Kasparov, and CAFASP by N. Siew D. Fischer Predicting the three-dimensional structure of a protein from its amino acid of Structure Prediction) blind prediction experiments aim to assess the prediction capabilities in the field

Fischer, Daniel

440

Emerging principles of regulatory evolution  

Science Journals Connector (OSTI)

...principles of regulatory evolution 10.1073/pnas.0700488104 Benjamin Prud'homme Nicolas Gompel Sean B. Carroll *Howard Hughes...1873 . 48 Protas ME Hersey C Kochanek D Zhou Y Wilkens H Jeffery WR Zon LI Borowsky R Tabin CJ ( 2006 ) Nat Genet 38 : 107...

Benjamin Prud'homme; Nicolas Gompel; Sean B. Carroll

2007-01-01T23:59:59.000Z

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


441

Cloud Formation, Evolution and Destruction  

E-Print Network [OSTI]

Chapter 4 Cloud Formation, Evolution and Destruction We now begin to trace the journey towards a star. How long does this take? The answer is surprisingly short: a good many clouds already contain new stars and these stars tend to be young. The typical cloud cannot spend long, if any time at all

Estalella, Robert

442

Requirements-driven software evolution  

Science Journals Connector (OSTI)

It is often the case that stakeholders want to strengthen/weaken or otherwise change their requirements for a system-to-be when certain conditions apply at runtime. For example, stakeholders may decide that if requirement R is violated more ... Keywords: Adaptive systems, Evolution, Modeling, Requirements, Requirements engineering

Vtor E. Souza; Alexei Lapouchnian; Konstantinos Angelopoulos; John Mylopoulos

2013-11-01T23:59:59.000Z

443

Investigation of Thermal Interface Materials Using Phase-Sensitive Transient Thermoreflectance Technique: Preprint  

SciTech Connect (OSTI)

With increasing power density in electronics packages/modules, thermal resistances at multiple interfaces are a bottleneck to efficient heat removal from the package. In this work, the performance of thermal interface materials such as grease, thermoplastic adhesives and diffusion-bonded interfaces are characterized using the phase-sensitive transient thermoreflectance technique. A multi-layer heat conduction model was constructed and theoretical solutions were derived to obtain the relation between phase lag and the thermal/physical properties. This technique enables simultaneous extraction of the contact resistance and bulk thermal conductivity of the TIMs. With the measurements, the bulk thermal conductivity of Dow TC-5022 thermal grease (70 to 75 um bondline thickness) was 3 to 5 W/(m-K) and the contact resistance was 5 to 10 mm2-K/W. For the Btech thermoplastic material (45 to 80 ?m bondline thickness), the bulk thermal conductivity was 20 to 50 W/(m-K) and the contact resistance was 2 to 5 mm2-K/W. Measurements were also conducted to quantify the thermal performance of diffusion-bonded interface for power electronics applications. Results with the diffusion-bonded sample showed that the interfacial thermal resistance is more than one order of magnitude lower than those of traditional TIMs, suggesting potential pathways to efficient thermal management.

Feng, X.; King, C.; DeVoto, D.; Mihalic, M.; Narumanchi, S.

2014-08-01T23:59:59.000Z

444

Fracture Evolution Following a Hydraulic Stimulation within an...  

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

Fracture Evolution Following a Hydraulic Stimulation within an EGS Reservoir Fracture Evolution Following a Hydraulic Stimulation within an EGS Reservoir Fracture Evolution...

445

Using and Measuring the Combined Heat and Power Advantage  

E-Print Network [OSTI]

Combined Heat and Power (CHP), also known as cogeneration, refers to the integration of thermal energy with power generation. CHP is a powerful energy conservation measure that has been identified as an important greenhouse gas reduction measure...

John, T.

2011-01-01T23:59:59.000Z

446

EVALUATION OF THERMAL CONDUCTIVITY OF INSTALLED-IN-PLACE POLYURETHANE FOAM INSULATION BY EXPERIMENT AND ANALYSIS  

SciTech Connect (OSTI)

In the thermal analysis of the 9977 package, it was found that calculated temperatures, determined using a typical thermal analysis code, did not match those measured in the experimental apparatus. The analysis indicated that the thermal resistance of the overpack in the experimental apparatus was less than that expected, based on manufacturer's reported value of thermal conductivity. To resolve this question, the thermal conductivity of the installed foam was evaluated from the experimental results, using a simplified analysis. This study confirmed that the thermal resistance of the experimental apparatus was lower than that which would result from the manufacturer's published values for thermal conductivity of the foam insulation. The test package was sectioned to obtain samples for measurement of material properties. In the course of the destructive examination a large uninsulated region was found at the bottom of the package, which accounted for the anomalous results. Subsequent measurement of thermal conductivity confirmed the manufacturer's published values. The study provides useful insight into the use of simplified, scoping calculations for evaluation of thermal performance of packages.

Smith, A; Bruce Hardy, B; Kurt Eberl, K; Nick Gupta, N

2007-12-05T23:59:59.000Z

447

Materials Selection Considerations for Thermal Process Equipment...  

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

Materials Selection Considerations for Thermal Process Equipment: A BestPractices Process Heating Technical Brief Materials Selection Considerations for Thermal Process Equipment:...

448

NREL: Energy Systems Integration Facility - Thermal Distribution...  

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

thermal distribution bus consists of a thermal water loop connected to a research boiler and chiller that provide precise and efficient control of the water temperature...

449

Integrated External Aerodynamic and Underhood Thermal Analysis...  

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

External Aerodynamic and Underhood Thermal Analysis for Heavy Vehicles Integrated External Aerodynamic and Underhood Thermal Analysis for Heavy Vehicles 2012 DOE Hydrogen and Fuel...

450

Continuous Processing of High Thermal Conductivity Polyethylene...  

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

Processing of High Thermal Conductivity Polyethylene Fibers and Sheets Continuous Processing of High Thermal Conductivity Polyethylene Fibers and Sheets Massachusetts Institute of...

451

Electric Motor Thermal Management | Department of Energy  

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

and Peer Evaluation Meeting ape030bennion2012o.pdf More Documents & Publications Electric Motor Thermal Management Electric Motor Thermal Management Vehicle Technologies...

452

Thermal Regenerator Testing | Department of Energy  

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

Thermal Regenerator Testing Thermal Regenerator Testing Poster presentation at the 2007 Diesel Engine-Efficiency & Emissions Research Conference (DEER 2007). 13-16 August, 2007,...

453

NREL: Energy Storage - Energy Storage Thermal Management  

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

Energy Storage Thermal Management Infrared image of rectangular battery cell. Infrared thermal image of a lithium-ion battery cell with poor terminal design. Graph of relative...

454

Solar Thermal Process Heat | Open Energy Information  

Open Energy Info (EERE)

Solar Thermal Process Heat Incentives Retrieved from "http:en.openei.orgwindex.php?titleSolarThermalProcessHeat&oldid267198" Category: Articles with outstanding TODO tasks...

455

OCEAN THERMAL ENERGY CONVERSION PROGRAMMATIC ENVIRONMENTAL ASSESSMENT  

E-Print Network [OSTI]

Ocean Thermal Energy Conversion (OTEC) Draft Programmaticof ocean thermal energy conversion technology. U.S. Depart~on Ocean TherUial Energy Conversion, June 18, 1979. Ocean

Sands, M.Dale

2013-01-01T23:59:59.000Z

456

Laser Texturing for Solar Thermal Systems  

Science Journals Connector (OSTI)

High solar absorptance and low thermal emittance is desired for absorber surface in solar thermal systems. Molybdenum surface was textured by pulsed fiber laser and...

Shah, Ankit; Gupta, Mool

457

Solar Keymark Testing of Solar Thermal Products  

Science Journals Connector (OSTI)

The Solar Keymark is the official CEN certification scheme for thermal solar collectors and factory made thermal solar systems. The Solar Keymark requires that the products fulfil the...

Harald Drck; Stephan Fischer

2009-01-01T23:59:59.000Z

458

Thermal-Mechanical Technologies | Argonne National Laboratory  

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

Thermal-Mechanical Technologies Thermal-Mechanical Technologies Heat management plays a critical role in almost all energy-related applications. Research topics in this area...

459

Power Electronic Thermal System Performance and Integration ...  

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

Power Electronic Thermal System Performance and Integration Power Electronic Thermal System Performance and Integration 2009 DOE Hydrogen Program and Vehicle Technologies Program...

460

Comparative genomics and genome evolution in yeasts  

Science Journals Connector (OSTI)

...Sternberg and Janet Thornton Comparative genomics and genome evolution in yeasts Kenneth...powerful model system for comparative genomics research. The availability of multiple...cerevisiae |evolution|bioinformatics|genomics| 1. Introduction The rationale put...

2006-01-01T23:59:59.000Z

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


461

Modeling Texture Evolution during Recrystallization in Aluminum  

E-Print Network [OSTI]

Modeling Texture Evolution during Recrystallization in Aluminum Abhijit Brahme1,2 , Joseph Fridy3, Aluminum, Grain Boundary Mobility, Nucleation, Oriented Growth, Oriented Nucleation, Stored Energy, Monte Carlo Modeling. #12;Modeling Texture Evolution during Recrystallization in Aluminum 2 1. Introduction

Rollett, Anthony D.

462

Landscape Evolution at an Active Plate Margin  

E-Print Network [OSTI]

Landscape Evolution at an Active Plate Margin edited and compiled by David R. Jessey and Robert E;32009 Desert Symposium Table of contents Landscape evolution at an active plate margin: a field trip

de Lijser, Peter

463

Domestic Heating and Thermal Insulation  

Science Journals Connector (OSTI)

... DIGEST 133 of the Building Research Station, entitled "Domestic Heating and Thermal Insulation" (Pp. 7. London : H.M. Stationery Office, 1960. 4insulation, the standard of heating, the ventilation-rate and the length of the heating season ...

1960-09-17T23:59:59.000Z

464

Thermal Insulation for Energy Conservation  

Science Journals Connector (OSTI)

The use of thermal insulations to reduce heat flow across the building ... decades. Materials available for use as building insulation include naturally occurring fibers and particles, man ... plastics, evacuated...

Dr. David W. Yarbrough Ph.D.; PE

2012-01-01T23:59:59.000Z

465

Thermal expansion of SOFC materials  

Science Journals Connector (OSTI)

A short overview is given for the thermal expansion of solid oxide fuel cell materials. The thermomechanical compatibility of state-of-the-art materials is compared with alternative, new materials. With these ...

F. Tietz

1999-01-01T23:59:59.000Z

466

Thermal Solar Power Plants Experience  

Science Journals Connector (OSTI)

In parallel with rising interest in solar power generation, several solar thermal facilities of different configuration and size were ... were designed as modest-size experimental or prototype solar power plants ...

W. Grasse; H. P. Hertlein; C.-J. Winter; G. W. Braun

1991-01-01T23:59:59.000Z

467

Thermal neutron flux perturbation due to indium foils in water  

E-Print Network [OSTI]

press) 13. Axford, R. A. , and Day, G. M. , personnel communication. 14. Ritchie, R. H. , Thermal Neutron Flux De ression, Health Physics Division Annual Prog. Rep. July, 1958, ORNL-2806, p. 133. 27 i 5, Walker, J. V. , "The Measurement of Absolute... Fluxes in Water and Graphite, " 'ORNL- 2842, 204 (f959). ...

Stinson, Ronald Calvin

1961-01-01T23:59:59.000Z

468

Thermo-optic noise in coated mirrors for high-precision optical measurements  

E-Print Network [OSTI]

Thermal fluctuations in the coatings used to make high-reflectors are becoming significant noise sources in precision optical measurements and are particularly relevant to advanced gravitational wave detectors. There are two recognized sources of coating thermal noise, mechanical loss and thermal dissipation. Thermal dissipation causes thermal fluctuations in the coating which produce noise via the thermo-elastic and thermo-refractive mechanisms. We treat these mechanisms coherently, give a correction for finite coating thickness, and evaluate the implications for Advanced LIGO.

M. Evans; S. Ballmer; M. Fejer; P. Fritschel; G. Harry; G. Ogin

2008-07-30T23:59:59.000Z

469

Thermal properties of the nuclear surface  

E-Print Network [OSTI]

The thermal evolution of a few thermodynamic properties of the nuclear surface like its thermodynamic potential energy, entropy and the symmetry free energy are examined for both semi-infinite nuclear matter and finite nuclei. The Thomas-Fermi model is employed. Three Skyrme interactions, namely, SkM$^*$, SLy4 and SK255 are used for the calculations to gauge the dependence of the nuclear surface properties on the energy density functionals. For finite nuclei, the surface observables are computed from a global liquid-drop inspired fit of the energies and free energies of a host of nuclei covering the entire periodic table. The hot nuclear system is modelled in a subtracted Thomas-Fermi framework. Compared to semi-infinite nuclear matter, substantial changes in the surface symmetry energy of finite nuclei are indicated; surface thermodynamic potential energies for the two systems are, however, not too different. Analytic expressions to fit the temperature and asymmetry dependence of the surface thermodynamic potential of semi-infinite nuclear matter and the temperature dependence of the surface free energy of finite nuclei are given.

B. K. Agrawal; D. Bandyopadhyay; J. N. De; S. K. Samaddar

2014-04-10T23:59:59.000Z

470

Guiding Architects in Selecting Architectural Evolution Alternatives  

SciTech Connect (OSTI)

Although there exist methods and tools to support architecture evolution, the derivation and evaluation of alternative evolution paths are realized manually. In this paper, we introduce an approach, where architecture specification is converted to a graph representation. Based on this representation, we automatically generate possible evolution paths, evalute quality attributes for different architecture configurations, and optimize the selection of a particular path accordingly. We illustrate our approach by modeling the software architecture evolution of a crisis management system.

Ciraci, Selim; Sozer, Hasan; Aksit, Mehmet

2011-09-09T23:59:59.000Z

471

Thermal Dileptons as Fireball Thermometer and Chronometer  

E-Print Network [OSTI]

Thermal dilepton radiation from the hot fireballs created in high-energy heavy-ion collisions provides unique insights into the properties of the produced medium. We first show how the predictions of hadronic many-body theory for a melting $\\rho$ meson, coupled with QGP emission utilizing a modern lattice-QCD based equation of state, yield a quantitative description of dilepton spectra in heavy-ion collisions at the SPS and the RHIC beam energy scan program. We utilize these results to systematically extract the excess yields and their invariant-mass spectral slopes to predict the excitation function of fireball lifetimes and (early) temperatures, respectively. We thereby demonstrate that future measurements of these quantities can yield unprecedented information on basic fireball properties. Specifically, our predictions quantify the relation between the measured and maximal fireball temperatures, and the proportionality of excess yields and total lifetime. This information can serve as a "caloric" curve to ...

Rapp, Ralf

2014-01-01T23:59:59.000Z

472

Strain compensation in boron-indium coimplanted laser thermal processed silicon  

E-Print Network [OSTI]

Strain compensation in boron-indium coimplanted laser thermal processed silicon Mark H. Clarka Strain in B-implanted laser thermal processed LTP silicon is reduced by coimplantation of In. Strain in the codoped layer is calculated using lattice constants measured by high-resolution x-ray diffraction

Florida, University of

473

Acceptability of Four Transformer Top-Oil Thermal Models: Pt. 2: Comparing Metrics  

E-Print Network [OSTI]

1 Acceptability of Four Transformer Top-Oil Thermal Models: Pt. 2: Comparing Metrics Lida Jauregui transformer top-oil thermal models are examined vis-à-vis training with measured data. Acceptability is unacceptable for model identification purposes. The linear top-oil model is acceptable for FOFA transformers

474

Near-infrared thermal lens spectrometer based on an erbium-doped fiber amplifier and  

E-Print Network [OSTI]

Near-infrared thermal lens spectrometer based on an erbium-doped fiber amplifier and an acousto, guanosine, and thymidine is described. © 1997 Optical Society of America Key words: Near infrared, thermal measurements of absorption in the near-IR region has been developed. In this instrument the near-IR excitation

Reid, Scott A.

475

Thermal Effects on Inverted Pendulum Thrust Stands for Steady-state High-power Plasma Thrusters  

E-Print Network [OSTI]

Thermal Effects on Inverted Pendulum Thrust Stands for Steady-state High-power Plasma Thrusters A and Aerospace Engineering Department Princeton University, Princeton, New Jersey 08544 AIAA-2003-4842§ July 22, 2003 Abstract Thermal effects on direct measurements of the thrust produced by steady-state, high-power

Choueiri, Edgar

476

THE EVOLUTION OF LYMAN LIMIT ABSORPTION SYSTEMS TO REDSHIFT SIX  

SciTech Connect (OSTI)

We have measured the redshift evolution of the density of Lyman limit systems (LLSs) in the intergalactic medium over the redshift range 0 < z < 6. We have used two new quasar samples to (1) improve coverage at z {approx} 1, with GALEX grism spectrograph observations of 50 quasars with 0.8 < z{sub em} < 1.3, and (2) extend coverage to z {approx} 6, with Keck ESI spectra of 25 quasars with 4.17 < z{sub em} < 5.99. Using these samples together with published data, we find that the number density of LLS per unit redshift, n(z), can be well fit by a simple evolution of the form n(z) = n{sub 3.5}[(1 + z)/4.5]{sup {gamma}} with n{sub 3.5} = 2.80 {+-} 0.33 and {gamma} = 1.94{sup +0.36}{sub -0.32} for the entire range 0 < z < 6. We have also reanalyzed the evolution of damped Ly{alpha} systems (DLAs) in the redshift range 4 < z < 5 using our high-redshift quasar sample. We find a total of 17 DLAs and sub-DLAs, which we have analyzed in combination with published data. The DLAs with log H{sub I} column density > 20.3 show the same redshift evolution as the LLS. When combined with previous results, our DLA sample is also consistent with a constant {Omega}{sub DLA} = 9 x 10{sup -4} from z = 2 to z = 5. We have used the LLS number density evolution to compute the evolution in the mean free path (mfp) of ionizing photons. We find a smooth evolution to z {approx} 6, very similar in shape to that of Madau et al. but about a factor of two higher. Recent theoretical models roughly match to the z < 6 data but diverge from the measured power law at z>6 in different ways, cautioning against extrapolating the fit to the mfp outside the measured redshift range.

Songaila, Antoinette; Cowie, Lennox L. [W. M. Keck Observatory, which is jointly operated by the California Institute of Technology, University of California, and National Aeronautics and Space Administration. (United States)

2010-10-01T23:59:59.000Z

477

Thermal Batteries for Electric Vehicles  

SciTech Connect (OSTI)

HEATS Project: UT Austin will demonstrate a high-energy density and low-cost thermal storage system that will provide efficient cabin heating and cooling for EVs. Compared to existing HVAC systems powered by electric batteries in EVs, the innovative hot-and-cold thermal batteries-based technology is expected to decrease the manufacturing cost and increase the driving range of next-generation EVs. These thermal batteries can be charged with off-peak electric power together with the electric batteries. Based on innovations in composite materials offering twice the energy density of ice and 10 times the thermal conductivity of water, these thermal batteries are expected to achieve a comparable energy density at 25% of the cost of electric batteries. Moreover, because UT Austins thermal energy storage systems are modular, they may be incorporated into the heating and cooling systems in buildings, providing further energy efficiencies and positively impacting the emissions of current building heating/cooling systems.

None

2011-11-21T23:59:59.000Z

478

Simple scheme for implementing the Deutsch-Jozsa algorithm in thermal cavity  

E-Print Network [OSTI]

We present a simple scheme to implement the Deutsch-Jozsa algorithm based on two-atom interaction in a thermal cavity. The photon-number-dependent parts in the evolution operator are canceled with the strong resonant classical field added. As a result, our scheme is immune to thermal field, and does not require the cavity to remain in the vacuum state throughout the procedure. Besides, large detuning between the atoms and the cavity is not necessary neither, leading to potential speed up of quantum operation. Finally, we show by numerical simulation that the proposed scheme is equal to demonstrate the Deutsch-Jozsa algorithm with high fidelity.

Wen-Xing Yang; Zhe-Xuan Gong

2006-11-22T23:59:59.000Z

479

Sustainable Evolution in an Ever-Changing Environment: General Characterization  

E-Print Network [OSTI]

A complex interplay between the academic issue about generalization of the thermodynamics and the practical matter about setting standards for a sustainable evolution of both tailored devices and natural systems is considered. It is established that the measure for a sustainable evolution in an ever-changing environment appears as a Boltzmann-Gibbs weight. At the same time, this measure performs as a local thermodynamical potential which, at the expense of being released from the condition of entropy maximization, serves as grounds for a fundamental development of the idea of banning perpetuum mobile. It is proven that the best efficiency of each engine that operates reversibly never exceeds the efficiency of corresponding Carnot heat engine where the engine is free from necessity of a physical coupling to two heat reservoirs.

Maria K. Koleva

2009-02-23T23:59:59.000Z

480

On the Origin of Bias, Scatter and Evolution in Sunyaev-Zel'dovich Effect Scaling Relations  

E-Print Network [OSTI]

The Sunyaev-Zel'dovich effect (SZE) observable-mass (Y-M) scaling relation is a promising technique for obtaining mass estimates for large samples of galaxy clusters and holds a key to studying the nature of dark matter and dark energy. However, cosmological inference based on SZE cluster surveys is limited by our incomplete knowledge of bias, scatter, and evolution in the Y-M relation. In this work, we investigate the effects of galaxy cluster mergers on the scaling relation using the Omega500 high-resolution cosmological hydrodynamic simulation. We show that the non-thermal pressure associated with merger-induced gas motions contributes significantly to the bias, scatter, and evolution of the scaling relation. After the merger, the kinetic energy of merging systems is slowly converted into thermal energy through dissipation of turbulent gas motions, which causes the thermal SZE signal to increase steadily with time. This post-merger evolution is one of the primary source of bias and scatter in the Y-M relat...

Yu, Liang; Nagai, Daisuke

2015-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "measuring thermal evolution" 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.


481

A Detailed Thermal Analysis of the Binospec Spectrograph  

E-Print Network [OSTI]

Refractive optics in astronomical instruments are potentially sensitive to temperature gradients and temperature transients. This sensitivity arises from thermally dependent refractive indices, lens spacings, and lens dimensions. We have therefore undertaken a detailed thermal analysis of Binospec, a wide-field optical spectrograph under development for the converted MMT. Our goals are to predict the temperature gradients that will be present in the Binospec optics and structure under realistic operating conditions and to determine how design choices affect these gradients. We begin our analysis by deriving thermal time constants for instrument subassemblies. We then generate a low-resolution finite difference model of the entire instrument and high-resolution models of sensitive subassemblies. This approach to thermal analysis is applicable to a variety of other instruments. We use measurements of the ambient temperature in the converted MMT's dome to model Binospec's thermal environment. During moderate conditions we find that the Binospec lens groups develop 0.14 C axial and radial temperature gradients and that lens groups of different mass develop 0.5 C temperature differences; these numbers are doubled for the extreme conditions. Internal heat sources do not significantly affect these results; heat flow from the environment dominates. The instrument must be periodically opened to insert new aperture masks, but we find that the resulting temperature gradients and thermal stresses in the optics are small. Image shifts at the detector caused by thermal deflections of the Binospec optical bench structure are approx 0.1 pixel/hr. We conclude that the proposed Binospec design has acceptable thermal properties, and briefly discuss design changes to further reduce temperature gradients.

Warren R. Brown; Daniel G. Fabricant; David A. Boyd

2002-10-28T23:59:59.000Z

482

Report on THMC Modeling of the Near Field Evolution of a Generic Clay  

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

on THMC Modeling of the Near Field Evolution of a Generic on THMC Modeling of the Near Field Evolution of a Generic Clay Repository: Model Validation and Demonstration Rev 2 Report on THMC Modeling of the Near Field Evolution of a Generic Clay Repository: Model Validation and Demonstration Rev 2 Shale and clay-rich rock formations have been considered as potential host rocks for geological disposal of high-level radioactive waste throughout the world. Coupled thermal, hydrological, mechanical, and chemical (THMC) processes have a significant impact on the long-term safety of a repository in this type of rocks. The validity of the two-part Hooke's model (TPHM), a new constitutive relationship, and associated formulations regarding rock hydraulic/mechanical properties is demonstrated by the consistency between observations from a mine-by test at the Mont Terri site

483

Thermal characterisation of a lightweight mortar containing expanded perlite for underground insulation  

Science Journals Connector (OSTI)

This paper aims to investigate the use of expanded perlite in mortar, for further application of shotcrete to thermal insulation of underground mines. Mixes were designed according to the typical proportions of underground shotcrete, with the sand volumetrically substituted by expanded perlite. Tests of samples were conducted at four ages. Transient plane source technique was utilised to measure the thermal properties. The results showed reduced weight, decreased thermal conductivity, deteriorated thermal diffusivity, and sacrificed mechanical strength with perlite addition. Experimental data analysis and explanation in this paper would establish useful fundamentals for further application of expanded perlite to underground shotcrete.

W.V. Liu; D.B. Apel; V. Bindiganavile

2011-01-01T23:59:59.000Z

484

Thermal storage module for solar dynamic receivers  

DOE Patents [OSTI]

A thermal energy storage system comprising a germanium phase change material and a graphite container.

Beatty, Ronald L. (Farragut, TN); Lauf, Robert J. (Oak Ridge, TN)

1991-01-01T23:59:59.000Z

485

NUMERICAL DESIGN TOOLS FOR THERMAL REPLICATION OF  

E-Print Network [OSTI]

by heating Ceramic block Glass workpiece before heating Figure 1: Thermal Replication (after Smith et al. [14NUMERICAL DESIGN TOOLS FOR THERMAL REPLICATION OF OPTICAL­QUALITY SURFACES Y.M. Stokes 1 Department. #12; Thermal replication of optical surfaces 1 1 Introduction Thermal replication is an industrial

Stokes, Yvonne

486

Battery Thermal Management System Design Modeling (Presentation)  

SciTech Connect (OSTI)

Presents the objectives and motivations for a battery thermal management vehicle system design study.

Kim, G-H.; Pesaran, A.

2006-10-01T23:59:59.000Z

487

Melt Rheology and Thermal Stability of Nanoclay Filled Poly(3hydroxybutyrate-co-4hydroxybutyrate) Biocomposites  

Science Journals Connector (OSTI)

Melt apparent shear viscosity for poly(3hydroxybutyrate-co-4hydroxybutyrate) composites filled with nanoclay was measured by means of a capillary...?1..., and thermal stability was conducted on a thermogravimetri...

Jia Yang; Lina Hang; Yahui Dai

2014-09-01T23:59:59.000Z

488

Field Analysis of Thermal Comfort in Two Energy Efficient Office Buildings in Malaysia  

E-Print Network [OSTI]

the effectiveness of tropical passive solar control components in integrating thermal comfort with energy efficiency in office building. Field measurements are carried out in selected workspace of two office buildings that have been practiced the passive solar...

Qahtan, A. T.; Keumala, N.; Rao, S. P.; Samad, Z. A.

2010-01-01T23:59:59.000Z

489

Thermal Bypass Air Barriers in the 2009 International Energy Conservation Code- Building America Top Innovation  

Broader source: Energy.gov [DOE]

This Building America Innovations profile describes Building America research supporting Thermal Bypass Air Barrier requirements. Since these were adopted in the 2009 IECC, close to one million homes have been mandated to include this vitally important energy efficiency measure.

490

Self-reactive rating of thermal runaway hazards on 18650 lithium-ion batteries  

Science Journals Connector (OSTI)

Vent sizing package 2 (VSP2) was used to measure the thermal hazard and runaway characteristics of 18650 lithium-ion batteries, which were manufactured by Sanyo Electric Co ... ., Ltd. Runaway reaction behaviors ...

C.-Y. Jhu; Y.-W. Wang; C.-Y. Wen

2011-10-01T23:59:59.000Z

491

Device for thermal transfer and power generation  

DOE Patents [OSTI]

A system is provided. The system includes a device that includes top and bottom thermally conductive substrates positioned opposite to one another, wherein a top surface of the bottom thermally conductive substrate is substantially atomically flat and a thermal blocking layer disposed between the top and bottom thermally conductive substrates. The device also includes top and bottom electrodes separated from one another between the top and bottom thermally conductive substrates to define a tunneling path, wherein the top electrode is disposed on the thermal blocking layer and the bottom electrode is disposed on the bottom thermally conductive substrate.

Weaver, Stanton Earl (Northville, NY); Arik, Mehmet (Niskayuna, NY)

2011-04-19T23:59:59.000Z

492

Diamond/aluminium nitride composites for efficient thermal management applications  

SciTech Connect (OSTI)

Synthetic diamond/AlN composite materials have been fabricated by a combination of microwave plasma-assisted chemical vapor deposition and molecular beam epitaxy. These wide band gap semiconductor heterojunctions show promises for many applications, including thermal management, deep ultraviolet light emitting devices, and high power and high temperature electronics. Here, we report results of an interface study of polycrystalline diamond layers grown on single crystal AlN(0001). High resolution transmission microscopy revealed atomically sharp interfaces between diamond and AlN. Temperature dependent Raman spectroscopy measurements showed reduced thermal resistance on diamond-coated AlN substrates compared to uncoated AlN at temperatures above 330 K.

Cervenka, J.; Dontschuk, N.; Prawer, S. [School of Physics, University of Melbourne, VIC (Australia); Ladouceur, F. [School of Electrical Engineering and Telecommunications, University of New South Wales, Sydney, NSW (Australia); Duvall, S. G. [Silanna Semiconductor Pty Ltd., Sydney, NSW (Australia)

2012-07-30T23:59:59.000Z

493

Density dependence of reactor performance with thermal confinement scalings  

SciTech Connect (OSTI)

Energy confinement scalings for the thermal component of the plasma published thus far have a different dependence on plasma density and input power than do scalings for the total plasma energy. With such thermal scalings, reactor performance (measured by Q, the ratio of the fusion power to the sum of the ohmic and auxiliary input powers) worsens with increasing density. This dependence is the opposite of that found using scalings based on the total plasma energy, indicating that reactor operation concepts may need to be altered if this density dependence is confirmed in future research.

Stotler, D.P.

1992-03-01T23:59:59.000Z

494

Thermal calibration of photodiode sensitivity for atomic force microscopy  

SciTech Connect (OSTI)

The photodiode sensitivity in the atomic force microscope is calibrated by relating the voltage noise to the thermal fluctuations of the cantilever angle. The method accounts for the ratio of the thermal fluctuations measured in the fundamental vibration mode to the total, and also for the tilt and extended tip of the cantilever. The method is noncontact and is suitable for soft or deformable surfaces where the constant compliance method cannot be used. For hard surfaces, the method can also be used to calibrate the cantilever spring constant.

Attard, Phil; Pettersson, Torbjoern; Rutland, Mark W. [School of Chemistry F11, University of Sydney, NSW 2006 Australia (Australia); Department of Chemistry, Royal Institute of Technology, SE-100 44 Stockholm, Sweden and Institute for Surface Chemistry, Box 5607, SE-114 86 Stockholm (Sweden)

2006-11-15T23:59:59.000Z

495

The CNOC2 Field Galaxy Luminosity Function I: A Description of Luminosity Function Evolution  

E-Print Network [OSTI]

We examine the evolution of the galaxy luminosity function (LF) using a sample of over 2000 galaxies, with 0.12 < z < 0.55 and 17.0 < Rc < 21.5, drawn from the Canadian Network for Observational Cosmology Field Galaxy Redshift Survey (CNOC2), at present the largest such sample at intermediate redshifts. We use UBVRcIc photometry to classify our galaxies into early, intermediate, and late types, for which we compute luminosity functions in the rest-frame B, Rc, and U bandpasses. In particular, we adopt a parameterization of LF evolution including luminosity and number density evolution, and take care to quantify correlations among our LF evolution parameters. Our principal result is a clear quantitative separation of luminosity and density evolution for different galaxy populations, and the finding that the character of the LF evolution is strongly dependent on galaxy type. Specifically, the early- and intermediate-type LF's show primarily brightening at higher redshifts and only modest density evolution, while the late-type LF is best f