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Effect of Growth Interruption on Surface Recombination Velocity in GaInAsSb/AlGaAsSb Heterostructures Grown by Organometallic Vapor Phase Epitaxy

Effect of Growth Interruption on Surface Recombination Velocity in GaInAsSb/AlGaAsSb Heterostructures Grown by Organometallic Vapor Phase Epitaxy

Date: April 29, 2004
Creator: Wang, CA; Shiau, DA; Donetsky, D; Anikeev, S; Belenky, G & Luryi, S
Description: The effects of growth interruption on the quality of GaInAsSb/AlGaAsSb heterostructures grown by organometallic vapor phase epitaxy are reported. In-situ reflectance monitoring and ex-situ characterization by high-resolution x-ray diffraction, 4K photoluminescence (PL), and time-resolved PL indicate that GaInAsSb is extremely sensitive to growth interruption time as well as the ambient atmosphere during interruption. By optimizing the interruption sequence, surface recombination velocity as low as 20 cm/s was achieved for GaInAsSb/AlGaAsSb double heterostructures.
Contributing Partner: UNT Libraries Government Documents Department
The Effect of H and He on Irradiation Performance of Fe and Ferritic Alloys

The Effect of H and He on Irradiation Performance of Fe and Ferritic Alloys

Date: January 22, 2010
Creator: Stubbins, James F.
Description: This research program was designed to look at basic radiation damage and effects and mechanical properties in Fe and ferritic alloys. The program scope included a number of materials ranging from pure single crystal Fe to more complex Fe-Cr-C alloys. The range of materials was designed to examine materials response and performance on ideal/model systems and gradually move to more complex systems. The experimental program was coordinated with a modeling effort. The use of pure and model alloys also facilitated the ability to develop and employ atomistic-scale modeling techniques to understand the inherent physics underlying materials performance
Contributing Partner: UNT Libraries Government Documents Department
Effect of H2S on performance of Pd4Pt alloy membranes

Effect of H2S on performance of Pd4Pt alloy membranes

Date: January 1, 2008
Creator: Howard, B.H. & Morreale, B.D.
Description: The effect of H2S on the performance of a hydrogen separation membrane with the composition Pd4Pt was evaluated at 350, 400 and 450°C. Exposure to hydrogen containing 1000 ppm H2S and 10%He resulted in two performance trends. At 350°C, a continuous decline in flux was observed which was attributed to the growth of sulphide corrosion on the membrane surface linked to surface contamination by stainless steel derived particles. At 400 and 450°C, the H2 flux decreased sharply followed by a slow recovery. This trend was attributed to Pt enrichment of the surface resulting from extraction of Pd through the formation of Pd4Pt. Also at 400 and 450°C, stainless steel based particle contamination was found to modify and/or enhance the corrosive effects of the H2S containing test gas. The implications of the metallic and/or metal sulphide surface contaminant effects are significant in that these contaminants could result in severe performance degradation and ultimately even mechanical failure.
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Effect of habitat and foraging height on bat activity in the coastal plain of South Carolina.

Effect of habitat and foraging height on bat activity in the coastal plain of South Carolina.

Date: July 1, 2005
Creator: Menzel, Jennifer, M.; Menzel, Michael A.; Kilgo, John C.; Ford, W. Mark; Edwards, John W. & McCracken, Gary F.
Description: A comparison of bat activity levels in the Coastal Plain of South Carolina among 5 habitat types: forested riparian areas, clearcuts, young pine plantations, mature pine plantations and pine savannas, using time expansion radio-microphones and integrated detectors to simultaneously monitor bat activity at three heights in each habitat type.
Contributing Partner: UNT Libraries Government Documents Department
Effect of hadron dynamics on the proton lifetime

Effect of hadron dynamics on the proton lifetime

Date: January 1, 2002
Creator: Silbar, R. R.; Goldhaber, A. S. (Alfred S.) & Goldman, T. (Terry)
Description: A detailed, quantitative re-examination of the effect of hadron dynamics on baryon decay, modeled in terms of Skyrme-field tunneling, indicates that any hadronic suppression should be quite mild. This appears to be another illustration of the 'Cheshire-cat' phenomenon, that variation of the apportionment between description of the nucleon as a bag of quarks and description as a Skyrme field configuration has little influence on many nucleon properties. Perhaps the largest remaining uncertainty in evaluating the decay rate has to do with the overlap between a specified quark-antiquark configuration and a final meson state.
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EFFECT OF HANFORD PLANT OPERATIONS ON THE TEMPERATURE OF THE COLUMBIA RIVER 1964 TO PRESENT.

EFFECT OF HANFORD PLANT OPERATIONS ON THE TEMPERATURE OF THE COLUMBIA RIVER 1964 TO PRESENT.

Date: January 1, 1970
Creator: Jaske, R.T. & Synoground, M.O.
Description: None
Contributing Partner: UNT Libraries Government Documents Department
The effect of head-on beam-beam compensation on the stochastic boundaries and particle diffusion in RHIC.

The effect of head-on beam-beam compensation on the stochastic boundaries and particle diffusion in RHIC.

Date: June 23, 2008
Creator: Abreu,N.; Beebe-Wang, J.; FischW; Luo, Y. & Robert-Demolaize, G.
Description: To compensate the effects from the head-on beam-beam interactions in the polarized proton operation in the Relativistic Heavy Ion Collider (RHIC), an electron lens (elens) is proposed to collide head-on with the proton beam. We used an extended version of SixTrack for multiparticle beam-beam simulation in order to study the effect of the e-lens on the stochastic boundary and also on diffusion. The stochastic boundary was analyzed using Lyapunov exponents and the diffusion was characterized as the increase in the rms spread of the action. For both studies the simulations were performed with and without the e-lens and with full and partial compensation. Using the simulated values of the diffusion an attempt to calculate the emittance growth rate is presented.
Contributing Partner: UNT Libraries Government Documents Department
Effect of Heat and Electricity Storage and Reliability on Microgrid Viability:A Study of Commercial Buildings in California and New York States

Effect of Heat and Electricity Storage and Reliability on Microgrid Viability:A Study of Commercial Buildings in California and New York States

Date: December 1, 2008
Creator: Stadler, Michael; Marnay, Chris; Siddiqui, Afzal; Lai, Judy; Coffey, Brian & Aki, Hirohisa
Description: In past work, Berkeley Lab has developed the Distributed Energy Resources Customer Adoption Model (DER-CAM). Given end-use energy details for a facility, a description of its economic environment and a menu of available equipment, DER-CAM finds the optimal investment portfolio and its operating schedule which together minimize the cost of meeting site service, e.g., cooling, heating, requirements. Past studies have considered combined heat and power (CHP) technologies. Methods and software have been developed to solve this problem, finding optimal solutions which take simultaneity into account. This project aims to extend on those prior capabilities in two key dimensions. In this research storage technologies have been added as well as power quality and reliability (PQR) features that provide the ability to value the additional indirect reliability benefit derived from Consortium for Electricity Reliability Technology Solutions (CERTS) Microgrid capability. This project is intended to determine how attractive on-site generation becomes to a medium-sized commercial site if economical storage (both electrical and thermal), CHP opportunities, and PQR benefits are provided in addition to avoiding electricity purchases. On-site electrical storage, generators, and the ability to seamlessly connect and disconnect from utility service would provide the facility with ride-through capability for minor grid disturbances. Three ...
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Effect of Heat and Electricity Storage and Reliability on Microgrid Viability: A Study of Commercial Buildings in California and New York States

Effect of Heat and Electricity Storage and Reliability on Microgrid Viability: A Study of Commercial Buildings in California and New York States

Date: March 10, 2009
Creator: Stadler, Michael; Marnay, Chris; Siddiqui, Afzal; Lai, Judy; Coffey, Brian & Aki, Hirohisa
Description: Berkeley Lab has for several years been developing methods for selection of optimal microgrid systems, especially for commercial building applications, and applying these methods in the Distributed Energy Resources Customer Adoption Model (DER-CAM). This project began with 3 major goals: (1) to conduct detailed analysis to find the optimal equipment combination for microgrids at a few promising commercial building hosts in the two favorable markets of California and New York, (2) to extend the analysis capability of DER-CAM to include both heat and electricity storage, and (3) to make an initial effort towards adding consideration of power quality and reliability (PQR) to the capabilities of DER-CAM. All of these objectives have been pursued via analysis of the attractiveness of a Consortium for Electric Reliability Technology Solutions (CERTS) Microgrid consisting of multiple nameplate 100 kW Tecogen Premium Power Modules (CM-100). This unit consists of an asynchronous inverter-based variable speed internal combustion engine genset with combined heat and power (CHP) and power surge capability. The essence of CERTS Microgrid technology is that smarts added to the on-board power electronics of any microgrid device enables stable and safe islanded operation without the need for complex fast supervisory controls. This approach allows plug and ...
Contributing Partner: UNT Libraries Government Documents Department
Effect of heat and power extraction on turbojet-engine performance I : analytical method of performance evaluation with compressor-outlet air bleed

Effect of heat and power extraction on turbojet-engine performance I : analytical method of performance evaluation with compressor-outlet air bleed

Date: March 1, 1950
Creator: Hensley, Reece V; Rom, Frank E & Koutz, Stanley L
Description: None
Contributing Partner: UNT Libraries Government Documents Department
Effect of heat and power extraction on turbojet-engine performance II : effect of compressor-outlet air bleed for specific modes of engine operation

Effect of heat and power extraction on turbojet-engine performance II : effect of compressor-outlet air bleed for specific modes of engine operation

Date: August 1, 1950
Creator: Rom, Frank E & Koutz, Stanley L
Description: None
Contributing Partner: UNT Libraries Government Documents Department
Effect of heat and power extraction on turbojet-engine performance III : analytical determination of effects of shaft-power extraction

Effect of heat and power extraction on turbojet-engine performance III : analytical determination of effects of shaft-power extraction

Date: October 1, 1950
Creator: Koutz, Stanley L; Hensley, Reece V & Rom, Frank E
Description: None
Contributing Partner: UNT Libraries Government Documents Department
Effect of heat-capacity lag on a variety of turbine-nozzle flow processes

Effect of heat-capacity lag on a variety of turbine-nozzle flow processes

Date: October 1, 1950
Creator: Spooner, Robert B
Description: None
Contributing Partner: UNT Libraries Government Documents Department
Effect of heat-capacity lag on the flow through oblique shock waves

Effect of heat-capacity lag on the flow through oblique shock waves

Date: October 1, 1950
Creator: Ivey, H Reese & Cline, Charles W
Description: None
Contributing Partner: UNT Libraries Government Documents Department
EFFECT OF HEAT FLUX ON THE CORROSION OF ALUMINUM BY WATER. PART IV. TESTS RELATIVE TO THE ADVANCED TEST REACTOR AND CORRELATION WITH PREVIOUS RESULTS

EFFECT OF HEAT FLUX ON THE CORROSION OF ALUMINUM BY WATER. PART IV. TESTS RELATIVE TO THE ADVANCED TEST REACTOR AND CORRELATION WITH PREVIOUS RESULTS

Date: February 1, 1964
Creator: Griess, J.C.; Savage, H.C. & English, J.L.
Description: The corrosion of 8081 and X-8001 aluminum alloys and the resultant formation of an adherent corrosion product on the corroding surface were investigated under conditions (except radiation) comparable to those that will exist on the surface of fuel-element cladding during operation of the Advanced Test Reactor. Since previous experiments indicated that corrosion penetration of the aluminum clad was unlikely during a reactor cycle provided the water chemistry is properly controlled, most of the studies in this investigation were concerned with the effect of variables on the rate of formation of corrosion- product films. These films have low thermal conductivity and can be a major factor in producing high fuel-element temperatures which lead to fuel-plate instabilities. The experimental procedures were the same as used in a similar study for the High Flux Isotope Reactor, but the ranges of variables investigated were greater than in previous studies. The 6061 and X-8001 alloys corroded to the same extent under the same test conditions until the corrosion product (boehmite) that formed on the surface bccame thick enough to spall spontaneously from the surface, usually about 2 mils thick. Spallation from the surface of the 6061 alloy was always accompanled by localized attack of the ...
Contributing Partner: UNT Libraries Government Documents Department
Effect of heat treatment and heat-to-heat variations in the fatigue-crack growth response of Alloy 718. Part 2. Microscopic observation

Effect of heat treatment and heat-to-heat variations in the fatigue-crack growth response of Alloy 718. Part 2. Microscopic observation

Date: April 1, 1980
Creator: Mills, W.J. & James, L.A.
Description: The microstructural aspects that influenced the room temperature and elevated temperature fatigue-crack propagation response of annealed, conventional, and modified heat-treated Alloy 718 were studied. Electron fractographic examination of Alloy 718 fatigue fracture surfaces revealed that operative crack growth mechanisms were dependent on heat treatment, heat-to-heat variations, temperature, and prevailing crack tip stress intensity level. In the low temperature regime (below 538{sup 0}C), all fracture surfaces exhibited a faceted appearance at low {Delta} levels, which is indicative of crystallographic fracture along intense inhomogeneous slip bands. The facets in the modified Alloy 718, however, were found to be rather poorly defined since the modified heat treatment tends to promote more homogeneous slip processes. Under progressively higher stress intensity levels, the room temperature and elevated temperature fatigue fracture surfaces exhibited striations, followed by a combination of striations and dimple rupture at the highest {Delta} values. Striation spacing measurements in all three heat-treated conditions were generally found to be in agreement with macroscopic growth rates at 24 and 538{sup 0}C. Under high temperature conditions (above 538{sup 0}C), evidence of intergranular fracture was also detected on the fatigue fracture surfaces, particularly at low stress intensity levels. This intergranular failure mechanism was found to be more ...
Contributing Partner: UNT Libraries Government Documents Department
Effect of heat treatment at 1,150 C on creep rupture properties of a Fe{sub 3}Al-based alloy

Effect of heat treatment at 1,150 C on creep rupture properties of a Fe{sub 3}Al-based alloy

Date: December 31, 1994
Creator: McKamey, C.G.; Maziasz, P.J. & Marrero-Santos, Y.
Description: The effects of heat treatment at 1,150 C on the creep-rupture properties of a Fe{sub 3}Al-based alloy were studied. Tests were conducted in air using various test temperatures and stresses. By plotting the data to a power-law equation, the activation energy for creep was determined to be approximately 150 kcal/mole and the creep exponent to be about 8. Optical metallography and scanning electron microscopy of ruptured specimens indicated that failure was in a ductile manner by microvoid coalescence at grain boundaries and triple points. Analytical electron microscopy was used to study characteristics of the microstructure and to identify Zr-rich precipitates that formed during heat treatment or creep testing. These precipitates were found to provide strengthening by pinning dislocations and grain boundaries.
Contributing Partner: UNT Libraries Government Documents Department
Effect of heat treatment at 1150 C on creep-rupture properties of alloy FA-180

Effect of heat treatment at 1150 C on creep-rupture properties of alloy FA-180

Date: August 1, 1996
Creator: McKamey, C.G. & Maziasz, P.J.
Description: The alloy FA-180, with a composition of Fe-28Al-5Cr-0.5Nb-0.8Mo-0.025Zr-0.05C-0.005B (at.%), is of interest because of its improved creep-rupture resistance when compared to alloy FA-129 (Fe-28Al-5Cr-0.5Nb-0.2C). At a temperature of 593 C and under a stress of 207 MPa, the creep-rupture life of FA-129 heat treated for 1 h at 750 C is about 20 h while the FA-180 alloy lasts approximately 100 h. Heat treatment at 1,150 C has been shown to further improve the creep life of FA-180 and creep-rupture lives of approximately 2,000 h have been attained. This strengthening was attributed to the presence of fine matrix and grain boundary Zr-rich MC precipitates that were produced by the heat treatment. The current study continues the investigation of the effect of heat treatment at 1,150 C on the improvement of creep-rupture life in alloy FA-180. As part of the effort to understand the strengthening mechanisms involved with heat treatment at 1,150 C, transmission electron microscopy was used to correlate the microstructure with the improved creep resistance. Results indicate that heat treatment at 1,150 C for 1 h, followed by rapid quenching in water or mineral oil, produces even further improvements in the creep-rupture life of this alloy. A specimen being ...
Contributing Partner: UNT Libraries Government Documents Department
Effect of heat treatment temperature on binder thermal conductivities

Effect of heat treatment temperature on binder thermal conductivities

Date: December 1, 1975
Creator: Wagner, P.
Description: The effect of heat treatment on the thermal conductivities of a pitch and a polyfurfuryl alcohol binder residue was investigated. Graphites specially prepared with these two binders were used for the experiments. Measured thermal conductivities were treated in terms of a two-component system, and the binder thermal conductivities were calculated. Both binder residues showed increased thermal conductivity with increased heat treatment temperature. (auth)
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Effect of heat treatment upon the microstructure and hardness of a wrought cobalt-base alloy stellite 21 (AMS 5385)

Effect of heat treatment upon the microstructure and hardness of a wrought cobalt-base alloy stellite 21 (AMS 5385)

Date: March 1, 1954
Creator: Clauss, F J & Weeton, J W
Description: None
Contributing Partner: UNT Libraries Government Documents Department
The Effect of Heat Treatments and Coatings on the Outgassing Rate of Stainless Steel Chambers

The Effect of Heat Treatments and Coatings on the Outgassing Rate of Stainless Steel Chambers

Date: March 1, 2014
Creator: Mamum, Md Abdullah A.; Elmustafa, Abdelmageed A,; Stutzman, Marcy L.; Adderley, Philip A. & Poelker, Matthew
Description: The outgassing rates of four nominally identical 304L stainless steel vacuum chambers were measured to determine the effect of chamber coatings and heat treatments. One chamber was coated with titanium nitride (TiN) and one with amorphous silicon (a-Si) immediately following fabrication. One chamber remained uncoated throughout, and the last chamber was first tested without any coating, and then coated with a-Si following a series of heat treatments. The outgassing rate of each chamber was measured at room temperatures between 15 and 30 deg C following bakes at temperatures between 90 and 400 deg C. Measurements for bare steel showed a significant reduction in the outgassing rate by more than a factor of 20 after a 400 deg C heat treatment (3.5 x 10{sup 12} TorrL s{sup -1}cm{sup -2} prior to heat treatment, reduced to 1.7 x 10{ sup -13} TorrL s{sup -1}cm{sup -2} following heat treatment). The chambers that were coated with a-Si showed minimal change in outgassing rates with heat treatment, though an outgassing rate reduced by heat treatments prior to a-Si coating was successfully preserved throughout a series of bakes. The TiN coated chamber exhibited remarkably low outgassing rates, up to four orders of magnitude lower than the ...
Contributing Partner: UNT Libraries Government Documents Department
EFFECT OF HEATING RATE ON THE THERMODYNAMIC PROPERTIES OF PULVERIZED COAL

EFFECT OF HEATING RATE ON THE THERMODYNAMIC PROPERTIES OF PULVERIZED COAL

Date: October 27, 1998
Creator: SAMPATH, RAMANATHAN
Description: This semi-annual technical progress report describes work performed under DOE Grant No. DE-FG22-96PC96224 during the period March 24, 1998 to September 23, 1998 which covers the fourth six months of the project. Existing laser heating set-up at the Single Particle Laboratory, Federal Energy Technology Center, Morgantown, WV would work only in the range of 10 to 10 4 5 K/s. During this reporting period, appropriate changes were made to the laser heating system to heat particles in the range of 10 to 10 K/s. Also, calibration for all the components of the 4 7 electrodynamic balance measurement system including single-color pyrometer and heating laser was successfully completed. Following the calibration, a large number of single coal particles were caught in the electrodynamic balance and their volume, external surface area, mass, and density were measured. The same single particles were then heated bidirectionally with a pulsed (10 ms pulse width) Nd:YAG laser beams of equal intensity. The temporal power variation in the laser pulse was monitored for use in the heat transfer analysis by an ultra-fast fiber optic uv light transmitter included in the beam path and coupled to a silicon photodiode. Measurements of changes in particle size that accompanied rapid ...
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EFFECT OF HEATING RATE ON THE THERMODYNAMIC PROPERTIES OF PULVERIZED COAL

EFFECT OF HEATING RATE ON THE THERMODYNAMIC PROPERTIES OF PULVERIZED COAL

Date: November 2, 1999
Creator: Sampath, Ramanathan
Description: This semi-annual technical progress report describes work performed under DOE Grant No. DE-FG22-96PC96224 during the period March 24, 1999 to September 23, 1999 which covers the last (sixth) six months of the project. During this reporting period, extraction of devolatilization time-scales and temperature data at these time-scales analyzing the high-speed films taken during the experiments was complete. Also a new thermodynamic model was developed to predict the heat transfer behavior for coal particles subjected to a range of heating rates using one approach based on the analogy of polymers. Sensitivity analyses of this model suggest that bituminous coal particles behave like polymers during rapid heating on the order of 10{sup 4}-10{sup 7} K/s. At these heating rates during the early stages within the first few milliseconds of heating time, the vibrational part of the heat capacity of the coal molecules appears to be still frozen but during the transition from heat-up to devolatization, the heat capacity appears to attain a sudden jump in its value as in the case of polymers. There are few data available in the coal literature for 10{sup 2}-10{sup 3} K/s obtained by UTRC in their previous studies. These data were obtained for a longer heating ...
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EFFECT OF HEATING RATE ON THE THERMODYNAMIC PROPERTIES OF PULVERIZED COAL

EFFECT OF HEATING RATE ON THE THERMODYNAMIC PROPERTIES OF PULVERIZED COAL

Date: January 1, 2000
Creator: Sampath, Ramanathan
Description: This final technical report describes work performed under DOE Grant No. DE-FG22-96PC96224 during the period September 24, 1996 to September 23, 1999 which covers the entire performance period of the project. During this period, modification, alignment, and calibration of the measurement system, measurement of devolatilization time-scales for single coal particles subjected to a range of heating rates and temperature data at these time-scales, and analysis of the temperature data to understand the effect of heating rates on coal thermal properties were carried out. A new thermodynamic model was developed to predict the heat transfer behavior for single coal particles using one approach based on the analogy for thermal property of polymers. Results of this model suggest that bituminous coal particles behave like polymers during rapid heating on the order of 10{sup 4}-10{sup 5} K/s. At these heating rates during the early stages of heating, the vibrational part of the heat capacity of the coal molecules appears to be still frozen but during the transition from heat-up to devolatilization, the heat capacity appears to attain a sudden jump in its value as in the case of polymers. There are a few data available in the coal literature for low heating rate ...
Contributing Partner: UNT Libraries Government Documents Department