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Sample records for microearthquake shear-wave splitting

  1. Shear-wave splitting and reservoir crack characterization: the...

    Open Energy Info (EERE)

    of its geothermal potential and day-to-day production. To detect the geometry and density of fracture systems we applied the shear-wave splitting technique to a large number...

  2. Micro-Earthquake At Coso Geothermal Area (2005) | Open Energy...

    Open Energy Info (EERE)

    at The Geysers and Coso Geothermal Reservoirs by Shear-wave Splitting, Rial, Elkibbi, Yang and Pereyra. The raw data for the project consists of seismographic recordings of...

  3. Micro-Earthquake At Geysers Area (Laney, 2005) | Open Energy...

    Open Energy Info (EERE)

    at The Geysers and Coso Geothermal Reservoirs by Shear-wave Splitting, Rial, Elkibbi, Yang and Pereyra. The raw data for the project consists of seismographic recordings of...

  4. Shear waves in acoustic anisotropic media (Journal Article) ...

    Office of Scientific and Technical Information (OSTI)

    Shear waves in acoustic anisotropic media Citation Details In-Document Search Title: Shear waves in acoustic anisotropic media Acoustic transversely isotropic (TI) media are ...

  5. Microearthquake Technology for EGS Fracture Characterization...

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

    Microearthquake Technology for EGS Fracture Characterization; 2010 Geothermal Technology Program Peer Review Report Microearthquake Technology for EGS Fracture Characterization; ...

  6. Anomalous shear wave attenuation in the shallow crust beneath...

    Open Energy Info (EERE)

    volcanic region, California Jump to: navigation, search OpenEI Reference LibraryAdd to library Journal Article: Anomalous shear wave attenuation in the shallow crust beneath the...

  7. Micro-Earthquake At Coso Geothermal Area (1992-1997) | Open Energy...

    Open Energy Info (EERE)

    processed. From the delay time of split shear waves, it was estimated that the crack density in the most active geothermal reservoir area (above 3 km depth) ranges between 0.030...

  8. Micro-Earthquake At Coso Geothermal Area (2002-2005) | Open Energy...

    Open Energy Info (EERE)

    reservoir crack characterization: the Coso geothermal field Rial, J.A.; Elkibbi, M.; Yang, M. (1 January 2005) Shear-wave splitting as a tool for the characterization of...

  9. Piezoelectric shear wave resonator and method of making same

    DOE Patents [OSTI]

    Wang, J.S.; Lakin, K.M.; Landin, A.R.

    1985-05-20

    An acoustic shear wave resonator comprising a piezoelectric film having its C-axis substantially inclined from the film normal such that the shear wave coupling coefficient significantly exceeds the longitudinal wave coupling coefficient, whereby the film is capable of shear wave resonance, and means for exciting said film to resonate. The film is prepared by deposition in a dc planar magnetron sputtering system to which a supplemental electric field is applied. The resonator structure may also include a semiconductor material having a positive temperature coefficient of resonance such that the resonator has a temperature coefficient of resonance approaching 0 ppM//sup 0/C.

  10. Piezoelectric shear wave resonator and method of making same

    DOE Patents [OSTI]

    Wang, J.S.; Lakin, K.M.; Landin, A.R.

    1983-10-25

    An acoustic shear wave resonator comprising a piezoelectric film having its C-axis substantially inclined from the film normal such that the shear wave coupling coefficient significantly exceeds the longitudinal wave coupling coefficient, whereby the film is capable of shear wave resonance, and means for exciting said film to resonate. The film is prepared by deposition in a dc planar magnetron sputtering system to which a supplemental electric field is applied. The resonator structure may also include a semiconductor material having a positive temperature coefficient of resonance such that the resonator has a temperature coefficient of resonance approaching 0 ppM//sup 0/C.

  11. Piezoelectric shear wave resonator and method of making same

    DOE Patents [OSTI]

    Wang, Jin S.; Lakin, Kenneth M.; Landin, Allen R.

    1988-01-01

    An acoustic shear wave resonator comprising a piezoelectric film having its C-axis substantially inclined from the film normal such that the shear wave coupling coefficient significantly exceeds the longitudinal wave coupling coefficient, whereby the film is capable of shear wave resonance, and means for exciting said film to resonate. The film is prepared by deposition in a dc planar magnetron sputtering system to which a supplemental electric field is applied. The resonator structure may also include a semiconductor material having a positive temperature coefficient of resonance such that the resonator has a temperature coefficient of resonance approaching 0 ppm/.degree.C.

  12. Method of making a piezoelectric shear wave resonator

    DOE Patents [OSTI]

    Wang, Jin S.; Lakin, Kenneth M.; Landin, Allen R.

    1987-02-03

    An acoustic shear wave resonator comprising a piezoelectric film having its C-axis substantially inclined from the film normal such that the shear wave coupling coefficient significantly exceeds the longitudinal wave coupling coefficient, whereby the film is capable of shear wave resonance, and means for exciting said film to resonate. The film is prepared by deposition in a dc planar magnetron sputtering system to which a supplemental electric field is applied. The resonator structure may also include a semiconductor material having a positive temperature coefficient of resonance such that the resonator has a temperature coefficient of resonance approaching 0 ppm/.degree.C.

  13. Conducting a 3D Converted Shear Wave Project to Reduce Exploration...

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

    Conducting a 3D Converted Shear Wave Project to Reduce Exploration Risk at Wister, CA Conducting a 3D Converted Shear Wave Project to Reduce Exploration Risk at Wister, CA DOE ...

  14. Micro-Earthquake At Snake River Plain Geothermal Region (1976...

    Open Energy Info (EERE)

    Micro-Earthquake At Snake River Plain Geothermal Region (1976) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Micro-Earthquake At Snake River...

  15. Micro-Earthquake At Northwest Basin and Range Geothermal Region...

    Open Energy Info (EERE)

    Micro-Earthquake At Northwest Basin and Range Geothermal Region (1976) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Micro-Earthquake At...

  16. Micro-Earthquake At Geysers Area (Erten & Rial, 1999) | Open...

    Open Energy Info (EERE)

    Micro-Earthquake At Geysers Area (Erten & Rial, 1999) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Micro-Earthquake At Geysers Area (Erten &...

  17. Conducting a 3D Converted Shear Wave Project to Reduce Exploration Risk at

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

    Wister, CA | Department of Energy Conducting a 3D Converted Shear Wave Project to Reduce Exploration Risk at Wister, CA Conducting a 3D Converted Shear Wave Project to Reduce Exploration Risk at Wister, CA DOE Geothermal Technologies Peer Review 2010 - Presentation. The primary objective of this project is to conduct a 3C 3D (converted shear wave) seismic survey to reduce exploration risk by characterizing fault and fracture geometrics at Wister, CA.The intent of the proposed program is to

  18. Microearthquake Technology for EGS Fracture Characterization; 2010

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

    Geothermal Technology Program Peer Review Report | Department of Energy Microearthquake Technology for EGS Fracture Characterization; 2010 Geothermal Technology Program Peer Review Report Microearthquake Technology for EGS Fracture Characterization; 2010 Geothermal Technology Program Peer Review Report DOE 2010 Geothermal Technologies Program Peer Review seismic_021_foulger.pdf (194.38 KB) More Documents & Publications Monitoring and Modeling Fluid Flow in a Developing Enhanced

  19. Microearthquake surveys of Snake River plain and Northwest Basin...

    Open Energy Info (EERE)

    microearthquakes; Nevada; North America; passive systems; Pershing County Nevada; Raft River; reservoir rocks; seismic methods; seismicity; seismology; Snake River plain;...

  20. Shear-wave splitting as a tool for the characterization of geothermal...

    Open Energy Info (EERE)

    extensions, from nearly a decade of practice. Authors Rial, J.A.; Elkibbi, M.; Yang and M. Published Journal Geothermics, 112005 DOI http:dx.doi.org10.1016...

  1. Apparatus for checking the direction of polarization of shear-wave ultrasonic transducers

    DOE Patents [OSTI]

    Karplus, H.H.B.; Forster, G.A.

    An apparatus for checking the direction of polarization of shear-wave ultrasonic transducers comprises a first planar surface for mounting the shear-wave transducer, a second planar surface inclined at a predetermined angle to the first surface to generate longitudinal waves by mode conversion, and a third planar surface disposed at a second predetermined angle to the first for mounting a longitudinal-wave ultransonic transducer. In an alternate embodiment, two second planar surfaces at the predetermined angle are placed at an angle to each other. The magnitude of the shear wave is a function of the angle between the direction of polarization of the transducer and the mode-conversion surface.

  2. Apparatus for checking the direction of polarization of shear-wave ultrasonic transducers

    DOE Patents [OSTI]

    Karplus, Henry H. B.

    1980-01-01

    An apparatus for checking the direction of polarization of shear-wave ultrasonic transducers comprises a first planar surface for mounting the shear-wave transducer, a second planar surface inclined at a predetermined angle to the first surface to generate longitudinal waves by mode conversion, and a third planar surface disposed at a second predetermined angle to the first for mounting a longitudinal-wave ultrasonic transducer. In an alternate embodiment, two second planar surfaces at the predetermined angle are placed at an angle to each other. The magnitude of the shear wave is a function of the angle between the direction of polarization of the transducer and the mode-conversion surface.

  3. Data interpretation of joint compressional and shear wave survey in mountainous region

    SciTech Connect (OSTI)

    Fugiu, D. )

    1992-01-01

    The join utilization of compressional and shear wave data leads one to discover nonstructural hydrocarbon traps such as stratigraphic trap, lithologic trap, fracture trap, etc. and to ascertain fluid situation in formation, lithologic variation and fracture zone, so that the accuracy of seismic data interpretation is improved greatly. In this paper, the author describes how to determine shear wave horizon, how to interpret carbonate reservoir and how to discover gas accumulation zone in HBC area in Sichuan Province. It is very important to pay more attention to analyzing the ratio between compressional wave amplitude and shear wave amplitude, and the ratio between compressional wave velocity and shear wave velocity in data interpretation. The amplitude ratio anomaly and the velocity ratio anomaly in HBC area can be usually seen at anticlinal axis areas and small noses. Generally speaking, the amplitude ratio anomaly area reflects gas accumulation and the velocity ratio anomaly area exhibits dense fracture zone. Good results have been obtained from exploratory wells in the areas where there occur the two anomalies simultaneously.

  4. Micro-Earthquake At Kilauea East Rift Geothermal Area (Thomas...

    Open Energy Info (EERE)

    At Kilauea East Rift Geothermal Area (Thomas, 1986) Exploration Activity Details Location Kilauea East Rift Geothermal Area Exploration Technique Micro-Earthquake Activity...

  5. Micro-Earthquake At Raft River Geothermal Area (1979) | Open...

    Open Energy Info (EERE)

    search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Micro-Earthquake At Raft River Geothermal Area (1979) Exploration Activity Details Location Raft River...

  6. Micro-Earthquake At Raft River Geothermal Area (2011) | Open...

    Open Energy Info (EERE)

    search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Micro-Earthquake At Raft River Geothermal Area (2011) Exploration Activity Details Location Raft River...

  7. Micro-Earthquake At Brady Hot Springs Geothermal Area (2011)...

    Open Energy Info (EERE)

    At Brady Hot Springs Geothermal Area (2011) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Micro-Earthquake At Brady Hot Springs Geothermal Area...

  8. Micro-Earthquake At Coso Geothermal Area (2007) | Open Energy...

    Open Energy Info (EERE)

    area Julian, B.R.; Foulger, G.R. (1 January 2010) IMPROVED METHODS FOR MAPPING PERMEABILITY AND HEAT SOURCES IN GEOTHERMAL AREAS USING MICROEARTHQUAKE DATA Additional...

  9. Micro-Earthquake At Dixie Valley Geothermal Area (Katz & J.,...

    Open Energy Info (EERE)

    Dixie Valley Geothermal Area (Katz & J., 1984) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Micro-Earthquake At Dixie Valley Geothermal Area...

  10. Micro-Earthquake At Long Valley Caldera Geothermal Area (Stroujkova...

    Open Energy Info (EERE)

    Micro-Earthquake At Long Valley Caldera Geothermal Area (Stroujkova & Malin, 2001) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity:...

  11. Micro-Earthquake At Under Steamboat Springs Area (Warpinski,...

    Open Energy Info (EERE)

    Technique Micro-Earthquake Activity Date Usefulness useful DOE-funding Unknown Notes Update to Warpinski, et al., 2002 References N. R. Warpinski, A. R. Sattler, R. Fortuna, D....

  12. Micro-Earthquake At Marysville Mt Area (Blackwell) | Open Energy...

    Open Energy Info (EERE)

    observed in the geothermal areas in the Salton Sea between 1-10 Hz (in units of power density). Because of this very low background noise the micro-earthquake survey was possible...

  13. Measurement of sound speed vs. depth in South Pole ice: pressure waves and shear waves

    SciTech Connect (OSTI)

    IceCube Collaboration; Klein, Spencer

    2009-06-04

    We have measured the speed of both pressure waves and shear waves as a function of depth between 80 and 500 m depth in South Pole ice with better than 1% precision. The measurements were made using the South Pole Acoustic Test Setup (SPATS), an array of transmitters and sensors deployed in the ice at the South Pole in order to measure the acoustic properties relevant to acoustic detection of astrophysical neutrinos. The transmitters and sensors use piezoceramics operating at {approx}5-25 kHz. Between 200 m and 500 m depth, the measured profile is consistent with zero variation of the sound speed with depth, resulting in zero refraction, for both pressure and shear waves. We also performed a complementary study featuring an explosive signal propagating vertically from 50 to 2250 m depth, from which we determined a value for the pressure wave speed consistent with that determined for shallower depths, higher frequencies, and horizontal propagation with the SPATS sensors. The sound speed profile presented here can be used to achieve good acoustic source position and emission time reconstruction in general, and neutrino direction and energy reconstruction in particular. The reconstructed quantities could also help separate neutrino signals from background.

  14. Microearthquake Studies at the Salton Sea Geothermal Field

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

    Templeton, Dennise

    The objective of this project is to detect and locate microearthquakes to aid in the characterization of reservoir fracture networks. Accurate identification and mapping of the large numbers of microearthquakes induced in EGS is one technique that provides diagnostic information when determining the location, orientation and length of underground crack systems for use in reservoir development and management applications. Conventional earthquake location techniques often are employed to locate microearthquakes. However, these techniques require labor-intensive picking of individual seismic phase onsets across a network of sensors. For this project we adapt the Matched Field Processing (MFP) technique to the elastic propagation problem in geothermal reservoirs to identify more and smaller events than traditional methods alone.

  15. Microearthquake Studies at the Salton Sea Geothermal Field

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

    Templeton, Dennise

    2013-10-01

    The objective of this project is to detect and locate microearthquakes to aid in the characterization of reservoir fracture networks. Accurate identification and mapping of the large numbers of microearthquakes induced in EGS is one technique that provides diagnostic information when determining the location, orientation and length of underground crack systems for use in reservoir development and management applications. Conventional earthquake location techniques often are employed to locate microearthquakes. However, these techniques require labor-intensive picking of individual seismic phase onsets across a network of sensors. For this project we adapt the Matched Field Processing (MFP) technique to the elastic propagation problem in geothermal reservoirs to identify more and smaller events than traditional methods alone.

  16. Micro-Earthquake At New River Area (DOE GTP) | Open Energy Information

    Open Energy Info (EERE)

    River Area (DOE GTP) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Micro-Earthquake At New River Area (DOE GTP) Exploration Activity Details...

  17. Micro-Earthquake At Newberry Caldera Area (DOE GTP) | Open Energy...

    Open Energy Info (EERE)

    Area (DOE GTP) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Micro-Earthquake At Newberry Caldera Area (DOE GTP) Exploration Activity Details...

  18. Shear Wave Velocity Structure of Southern African Crust: Evidence for Compositional Heterogeneity within Archaean and Proterozoic Terrains

    SciTech Connect (OSTI)

    Kgaswane, E M; Nyblade, A A; Julia, J; Dirks, P H H M; Durrheim, R J; Pasyanos, M E

    2008-11-11

    Crustal structure in southern Africa has been investigated by jointly inverting receiver functions and Rayleigh wave group velocities for 89 broadband seismic stations spanning much of the Precambrian shield of southern Africa. 1-D shear wave velocity profiles obtained from the inversion yield Moho depths that are similar to those reported in previous studies and show considerable variability in the shear wave velocity structure of the lower part of the crust between some terrains. For many of the Archaean and Proterozoic terrains in the shield, S velocities reach 4.0 km/s or higher over a substantial part of the lower crust. However, for most of the Kimberley terrain and adjacent parts of the Kheis Province and Witwatersrand terrain, as well as for the western part of the Tokwe terrain, mean shear wave velocities of {le} 3.9 km/s characterize the lower part of the crust along with slightly ({approx}5 km) thinner crust. These findings indicate that the lower crust across much of the shield has a predominantly mafic composition, except for the southwest portion of the Kaapvaal Craton and western portion of the Zimbabwe Craton, where the lower crust is intermediate-to-felsic in composition. The parts of the Kaapvaal Craton underlain by intermediate-to-felsic lower crust coincide with regions where Ventersdorp rocks have been preserved, and thus we suggest that the intermediate-to-felsic composition of the lower crust and the shallower Moho may have resulted from crustal melting during the Ventersdorp tectonomagmatic event at c. 2.7 Ga and concomitant crustal thinning caused by rifting.

  19. Integrated test plan for crosswell compressional and shear wave seismic tomography for site characterization at the VOC Arid Site

    SciTech Connect (OSTI)

    Elbring, G.J.; Narbutovskih, S.M.

    1994-02-01

    This integrated test plan describes the demonstration of the crosswell acoustic tomography technique as part of the Volatile Organic Compounds-Arid Integrated Demonstration (VOC-Arid ID). The purpose of this demonstration is to image the subsurface seismic velocity structure and to relate the resulting velocity model to lithology and saturation. In fiscal year (FY) 1994 an initial fielding will test three different downhole sources at two different sites at the Hanford US Department of Energy facility to identify which sources will provide the energy required to propagate between existing steel-cased wells at these two sites. Once this has been established, a second fielding will perform a full compressional and shear wave tomographic survey at the most favorable site. Data reduction, analysis, and interpretation of this full data set will be completed by the end of this fiscal year. Data collection for a second survey will be completed by the end of the fiscal year, and data reduction for this data set will be completed in FY 1995. The specific need is detailed subsurface characterization with minimum intrusion. This technique also has applications for long term vadose zone monitoring for both Resource Conservation and Recovery Act (RCRA) waste storage facilities and for remediation monitoring. Images produced are continuous between boreholes. This is a significant improvement over the single point data derived solely from core information. Saturation changes, either naturally occurring (e.g., perched water tables) or remediation induced (e.g., water table mounding from injection wells or during inwell air sparging) could be imaged. These crosswell data allow optimal borehole placement for groundwater remediation, associated monitoring wells and possibly evaluation of the effective influence of a particular remediation technique.

  20. Reservoir fracture mapping using microearthquakes: Austin chalk, Giddings field, TX and 76 field, Clinton Co., KY

    SciTech Connect (OSTI)

    Phillips, W.S.; Rutledge, J.T.; Gardner, T.L.; Fairbanks, T.D.; Miller, M.E.; Schuessler, B.K.

    1996-11-01

    Patterns of microearthquakes detected downhole defined fracture orientation and extent in the Austin chalk, Giddings field, TX and the 76 field, Clinton Co., KY. We collected over 480 and 770 microearthquakes during hydraulic stimulation at two sites in the Austin chalk, and over 3200 during primary production in Clinton Co. Data were of high enough quality that 20%, 31% and 53% of the events could be located, respectively. Reflected waves constrained microearthquakes to the stimulated depths at the base of the Austin chalk. In plan view, microearthquakes defined elongate fracture zones extending from the stimulation wells parallel to the regional fracture trend. However, widths of the stimulated zones differed by a factor of five between the two Austin chalk sites, indicating a large difference in the population of ancillary fractures. Post-stimulation production was much higher from the wider zone. At Clinton Co., microearthquakes defined low-angle, reverse-fault fracture zones above and below a producing zone. Associations with depleted production intervals indicated the mapped fractures had been previously drained. Drilling showed that the fractures currently contain brine. The seismic behavior was consistent with poroelastic models that predicted slight increases in compressive stress above and below the drained volume.

  1. Split gland

    DOE Patents [OSTI]

    Petranto, Joseph J.

    1982-01-01

    The disclosure relates to a split gland laterally fittable over tubing. Two essentially mirror image half glands are juxtaposed, held together by a spring clip and aligned by a retainer.

  2. Characterization and application of microearthquake clusters to problems of scaling, fault zone dynamics, and seismic monitoring at Parkfield, California

    SciTech Connect (OSTI)

    Nadeau, R.M.

    1995-10-01

    This document contains information about the characterization and application of microearthquake clusters and fault zone dynamics. Topics discussed include: Seismological studies; fault-zone dynamics; periodic recurrence; scaling of microearthquakes to large earthquakes; implications of fault mechanics and seismic hazards; and wave propagation and temporal changes.

  3. Split gland

    DOE Patents [OSTI]

    Petranto, Joseph J. (Los Alamos, NM)

    1989-01-01

    A split gland having only three parts is described. The gland has substantially the same stability to the relative motion of the constituent half-gland members during the attachment process to a female fitting as have more complicated designs. Ease of manufacture and use result from the reduction in complexity of the present invention.

  4. Split gland

    DOE Patents [OSTI]

    Petranto, J.J.

    1989-09-05

    A split gland having only three parts is described. The gland has substantially the same stability to the relative motion of the constituent half-gland members during the attachment process to a female fitting as have more complicated designs. Ease of manufacture and use result from the reduction in complexity of the present invention. 15 figs.

  5. Microearthquakes induced by a hydraulic injection in sedimentary rock, East Texas

    SciTech Connect (OSTI)

    House, L.; Flores, R.; Withers, R.

    1996-08-01

    In October, 1993, ARCO carried out a hydraulic injection near Beaumont, TX, into an unconsolidated sand, the Frio Formation. Fluid was injected into a 55m long zone at a depth of 1350 m. Four separate injections were done during 5 days. A total of more than 2.1 million gallons of bentonite slurry was injected, along with more than 3 million pounds of sand. Downhole fluid injection pressures ranged between about 3000 and 3500 psi. Induced microearthquakes were monitored by a set of 25 geophone packages situated in each of two monitoring well. More than 2400 microearthquakes were recorded during the injection, although most were too small to locate reliably using arrival times. A total of 54 microearthquakes were selected for detailed study. They were precisely located using arrival times of P and S phases from both of the monitoring boreholes. These locations are distributed non-uniformly, with a cluster near the injection borehole, a linear distribution about 200 m from the injection borehole, and a relatively quiet zone in between. The relatively nonseismic behavior in the middle zone compared to the other two zones suggests that this zone represent a discontinuity in the Frio Formation, although no obvious discontinuity has been identified from logs or nearby seismic reflection profiles. The large vertical extent of the geophone packages allowed an inversion of the arrival times for transverse isotropic elastic parameters, which yielded Vp anisotropy of about -13% and Vs of about -2%. Since these anisotropy values indicate that the vertical Vp and Vs are larger than the horizontal, they are surprising for this well bedded formation. Single-event focal mechanisms could be determined for 47 of the microearthquakes, and all are shear slip type. They show a large range of mechanisms, ranging from normal to reverse slip. Normal or oblique-normal slip predominant though, with T (tensional) axes generally nearly horizontal and approximately N-S. 3 refs., 4 figs., 1 tab.

  6. Microearthquake Study of the Salton Sea Geothermal Field, California: Evidence of Stress Triggering - Masters Thesis

    SciTech Connect (OSTI)

    Holland, Austin Adams

    2002-02-01

    A digital network of 24 seismograph stations was operated from September 15, 1987 to September 30, 1988, by Lawrence Livermore National Laboratory and Unocal as part of the Salton Sea Scientific Drilling Project to study seismicity related to tectonics and geothermal activity near the drilling site. More than 2001 microearthquakes were relocated in this study in order to image any pervasive structures that may exist within the Salton Sea geothermal field. First, detailed velocity models were obtained through standard 1-D inversion techniques. These velocity models were then used to relocate events using both single event methods and Double-Differencing, a joint hypocenter location method. An anisotropic velocity model was built from anisotropy estimates obtained from well logs within the study area. During the study period, the Superstition wills sequence occurred with two moderate earthquakes of MS 6.2 and MS 6.6. These moderate earthquakes caused a rotation of the stress field as observed from the inversion of first motion data from microearthquakes at the Salton Sea geothermal field. Coulomb failure analysis also indicates that microearthquakes occurring after the Superstition Hills sequence are located within a region of stress increase suggesting stress triggering caused by the moderate earthquakes.

  7. Thermocouple split follower

    DOE Patents [OSTI]

    Howell, deceased, Louis J.

    1980-01-01

    Thermoelectric generator assembly accommodating differential thermal expansion between thermoelectric elements by means of a cylindrical split follower forming a slot and having internal spring loaded wedges that permit the split follower to open and close across the slot.

  8. Shear wave transducer for boreholes

    DOE Patents [OSTI]

    Mao, N.H.

    1984-08-23

    A technique and apparatus is provided for estimating in situ stresses by measuring stress-induced velocity anisotropy around a borehole. Two sets each of radially and tangentially polarized transducers are placed inside the hole with displacement directions either parallel or perpendicular to the principal stress directions. With this configuration, relative travel times are measured by both a pulsed phase-locked loop technique and a cross correlation of digitized waveforms. The biaxial velocity data are used to back-calculate the applied stress.

  9. Real-time fracture monitoring in Engineered Geothermal Systems with seismic waves

    SciTech Connect (OSTI)

    Jose A. Rial; Jonathan Lees

    2009-03-31

    As proposed, the main effort in this project is the development of software capable of performing real-time monitoring of micro-seismic activity recorded by an array of sensors deployed around an EGS. The main milestones are defined by the development of software to perform the following tasks: • Real-time micro-earthquake detection and location • Real-time detection of shear-wave splitting • Delayed-time inversion of shear-wave splitting These algorithms, which are discussed in detail in this report, make possible the automatic and real-time monitoring of subsurface fracture systems in geothermal fields from data collected by an array of seismic sensors. Shear wave splitting (SWS) is parameterized in terms of the polarization of the fast shear wave and the time delay between the fast and slow shear waves, which are automatically measured and stored. The measured parameters are then combined with previously measured SWS parameters at the same station and used to invert for the orientation (strike and dip) and intensity of cracks under that station. In addition, this grant allowed the collection of seismic data from several geothermal regions in the US (Coso) and Iceland (Hengill) to use in the development and testing of the software.

  10. Final technical report

    SciTech Connect (OSTI)

    J.A. Rial; J. Lees

    2009-03-31

    As proposed, the main effort in this project is the development of software capable of performing real-time monitoring of micro-seismic activity recorded by an array of sensors deployed around an EGS. The main milestones are defined by the development of software to perform the following tasks: • Real-time micro-earthquake detection and location • Real-time detection of shear-wave splitting • Delayed-time inversion of shear-wave splitting These algorithms, which are discussed in detail in this report, make possible the automatic and real-time monitoring of subsurface fracture systems in geothermal fields from data collected by an array of seismic sensors. Shear wave splitting (SWS) is parameterized in terms of the polarization of the fast shear wave and the time delay between the fast and slow shear waves, which are automatically measured and stored. The measured parameters are then combined with previously measured SWS parameters at the same station and used to invert for the orientation (strike and dip) and intensity of cracks under that station. In addition, this grant allowed the collection of seismic data from several geothermal regions in the US (Coso) and Iceland (Hengill) to use in the development and testing of the software.

  11. Split University | Open Energy Information

    Open Energy Info (EERE)

    Name: Split University Place: Zagreb, Croatia Sector: Hydro, Solar Product: Croatia-based electrical engineering faculty of Split University. Involved in developing small hydro and...

  12. Split image optical display

    DOE Patents [OSTI]

    Veligdan, James T.

    2005-05-31

    A video image is displayed from an optical panel by splitting the image into a plurality of image components, and then projecting the image components through corresponding portions of the panel to collectively form the image. Depth of the display is correspondingly reduced.

  13. Split image optical display

    DOE Patents [OSTI]

    Veligdan, James T.

    2007-05-29

    A video image is displayed from an optical panel by splitting the image into a plurality of image components, and then projecting the image components through corresponding portions of the panel to collectively form the image. Depth of the display is correspondingly reduced.

  14. Application of the Split Hopkinson Resonant Bar Test for Seismic Property Characterization of Hydrate-bearing Sand Undergoing Water Saturation

    SciTech Connect (OSTI)

    Nakagawa, S.; Kneafsey, T.J.

    2011-05-03

    Conventional resonant bar tests allow the measurement of seismic properties of rocks and sediments at low frequencies (several kilohertz). However, the tests require a long, slender sample which is often difficult to obtain from the deep subsurface and weak and fractured formations. We present an alternative low-frequency measurement technique to the conventional resonant bar tests. This technique involves a jacketed core sample placed between a pair of long, metal extension rods with attached seismic source and receiver—the same geometry as the split Hopkinson pressure bar test for large-strain, dynamic impact experiments. Because of the added length and mass to the sample, the resonance frequency of the entire system can be lowered significantly, compared to the sample alone. The proposed “Split Hopkinson Resonant Bar (SHRB)” test is applied in two steps. In the first step, extension and torsion-mode resonance frequencies and attenuation of the system are measured. Then, numerical inversions for the compressional and shear wave velocities and attenuation are performed. We initially applied the SHRB test to synthetic materials (plastics) for testing its accuracy, then used it for measuring the seismic velocities and attenuation of a rock core containing supercritical CO{sub 2}, and a sediment core while methane hydrate formed in the pore space.

  15. Analysis of Injection-Induced Micro-Earthquakes in a Geothermal Steam Reservoir, The Geysers Geothermal Field, California

    SciTech Connect (OSTI)

    Rutqvist, Jonny; Rutqvist, J.; Oldenburg, C.M.

    2008-05-15

    In this study we analyze relative contributions to the cause and mechanism of injection-induced micro-earthquakes (MEQs) at The Geysers geothermal field, California. We estimated the potential for inducing seismicity by coupled thermal-hydrological-mechanical analysis of the geothermal steam production and cold water injection to calculate changes in stress (in time and space) and investigated if those changes could induce a rock mechanical failure and associated MEQs. An important aspect of the analysis is the concept of a rock mass that is critically stressed for shear failure. This means that shear stress in the region is near the rock-mass frictional strength, and therefore very small perturbations of the stress field can trigger an MEQ. Our analysis shows that the most important cause for injection-induced MEQs at The Geysers is cooling and associated thermal-elastic shrinkage of the rock around the injected fluid that changes the stress state in such a way that mechanical failure and seismicity can be induced. Specifically, the cooling shrinkage results in unloading and associated loss of shear strength in critically shear-stressed fractures, which are then reactivated. Thus, our analysis shows that cooling-induced shear slip along fractures is the dominant mechanism of injection-induced MEQs at The Geysers.

  16. Advanced Water Splitting Materials EMN Workshop

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

    Advanced Water Splitting Materials EMN Workshop Stanford, CA April 14 th , 2016 Dr. Eric ... Laying a Foundation.. ...for an Advanced Water Splitting Materials EMN for renewable H 2 ...

  17. Hydrogen Production: Photoelectrochemical Water Splitting

    Broader source: Energy.gov [DOE]

    In photoelectrochemical (PEC) water splitting, hydrogen is produced from water using sunlight and specialized semiconductors called photoelectrochemical materials, which use light energy to directly dissociate water molecules into hydrogen and oxygen.

  18. Split ring containment attachment device

    DOE Patents [OSTI]

    Sammel, Alfred G.

    1996-01-01

    A containment attachment device 10 for operatively connecting a glovebag 200 to plastic sheeting 100 covering hazardous material. The device 10 includes an inner split ring member 20 connected on one end 22 to a middle ring member 30 wherein the free end 21 of the split ring member 20 is inserted through a slit 101 in the plastic sheeting 100 to captively engage a generally circular portion of the plastic sheeting 100. A collar potion 41 having an outer ring portion 42 is provided with fastening means 51 for securing the device 10 together wherein the glovebag 200 is operatively connected to the collar portion 41.

  19. Cool covered sky-splitting spectrum-splitting FK

    SciTech Connect (OSTI)

    Mohedano, Rubén; Chaves, Julio; Falicoff, Waqidi; Hernandez, Maikel; Sorgato, Simone; Miñano, Juan C.; Benitez, Pablo; Buljan, Marina

    2014-09-26

    Placing a plane mirror between the primary lens and the receiver in a Fresnel Köhler (FK) concentrator gives birth to a quite different CPV system where all the high-tech components sit on a common plane, that of the primary lens panels. The idea enables not only a thinner device (a half of the original) but also a low cost 1-step manufacturing process for the optics, automatic alignment of primary and secondary lenses, and cell/wiring protection. The concept is also compatible with two different techniques to increase the module efficiency: spectrum splitting between a 3J and a BPC Silicon cell for better usage of Direct Normal Irradiance DNI, and sky splitting to harvest the energy of the diffuse radiation and higher energy production throughout the year. Simple calculations forecast the module would convert 45% of the DNI into electricity.

  20. Advanced Water Splitting Materials Workshop Agenda

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

    Water Splitting Materials Workshop Agenda Thursday, April 14, 2016 Room 8:00 am Check-in Outside Clubhouse Ballroom Renewable H 2 Production and the Advanced Water Splitting EMN ...

  1. EA-225 Split Rock Energy LLC | Department of Energy

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

    5 Split Rock Energy LLC EA-225 Split Rock Energy LLC Order authorizing Split Rock Energy LLC to export electric energy to Canada. EA-225 Split Rock Energy LLC (34.81

  2. Algebraic techniques for diagonalization of a split quaternion matrix in split quaternionic mechanics

    SciTech Connect (OSTI)

    Jiang, Tongsong; Jiang, Ziwu; Zhang, Zhaozhong

    2015-08-15

    In the study of the relation between complexified classical and non-Hermitian quantum mechanics, physicists found that there are links to quaternionic and split quaternionic mechanics, and this leads to the possibility of employing algebraic techniques of split quaternions to tackle some problems in complexified classical and quantum mechanics. This paper, by means of real representation of a split quaternion matrix, studies the problem of diagonalization of a split quaternion matrix and gives algebraic techniques for diagonalization of split quaternion matrices in split quaternionic mechanics.

  3. Minimal Doubling and Point Splitting

    SciTech Connect (OSTI)

    Creutz, M.

    2010-06-14

    Minimally-doubled chiral fermions have the unusual property of a single local field creating two fermionic species. Spreading the field over hypercubes allows construction of combinations that isolate specific modes. Combining these fields into bilinears produces meson fields of specific quantum numbers. Minimally-doubled fermion actions present the possibility of fast simulations while maintaining one exact chiral symmetry. They do, however, introduce some peculiar aspects. An explicit breaking of hyper-cubic symmetry allows additional counter-terms to appear in the renormalization. While a single field creates two different species, spreading this field over nearby sites allows isolation of specific states and the construction of physical meson operators. Finally, lattice artifacts break isospin and give two of the three pseudoscalar mesons an additional contribution to their mass. Depending on the sign of this mass splitting, one can either have a traditional Goldstone pseudoscalar meson or a parity breaking Aoki-like phase.

  4. Precision aligned split V-block

    DOE Patents [OSTI]

    George, Irwin S.

    1984-01-01

    A precision aligned split V-block for holding a workpiece during a milling operation having an expandable frame for allowing various sized workpieces to be accommodated, is easily secured directly to the mill table and having key lugs in one base of the split V-block that assures constant alignment.

  5. Ductless, Mini-Split Heat Pump Basics

    Broader source: Energy.gov [DOE]

    Ductless, mini-split-system heat pumps (mini splits), as their name implies, do not have ducts. Therefore, they make good retrofit add-ons to houses or buildings with "non-ducted" heating systems, such as hydronic (hot water heat), radiant panels, and space heaters (wood, kerosene, propane).

  6. Innovative solar thermochemical water splitting.

    SciTech Connect (OSTI)

    Hogan, Roy E. Jr.; Siegel, Nathan P.; Evans, Lindsey R.; Moss, Timothy A.; Stuecker, John Nicholas; Diver, Richard B., Jr.; Miller, James Edward; Allendorf, Mark D.; James, Darryl L.

    2008-02-01

    Sandia National Laboratories (SNL) is evaluating the potential of an innovative approach for splitting water into hydrogen and oxygen using two-step thermochemical cycles. Thermochemical cycles are heat engines that utilize high-temperature heat to produce chemical work. Like their mechanical work-producing counterparts, their efficiency depends on operating temperature and on the irreversibility of their internal processes. With this in mind, we have invented innovative design concepts for two-step solar-driven thermochemical heat engines based on iron oxide and iron oxide mixed with other metal oxides (ferrites). The design concepts utilize two sets of moving beds of ferrite reactant material in close proximity and moving in opposite directions to overcome a major impediment to achieving high efficiency--thermal recuperation between solids in efficient counter-current arrangements. They also provide inherent separation of the product hydrogen and oxygen and are an excellent match with high-concentration solar flux. However, they also impose unique requirements on the ferrite reactants and materials of construction as well as an understanding of the chemical and cycle thermodynamics. In this report the Counter-Rotating-Ring Receiver/Reactor/Recuperator (CR5) solar thermochemical heat engine and its basic operating principals are described. Preliminary thermal efficiency estimates are presented and discussed. Our ferrite reactant material development activities, thermodynamic studies, test results, and prototype hardware development are also presented.

  7. Extremely stable bare hematite photoanode for solar water splitting...

    Office of Scientific and Technical Information (OSTI)

    Extremely stable bare hematite photoanode for solar water splitting Prev Next Title: Extremely stable bare hematite photoanode for solar water splitting Authors: Dias, Paula ; ...

  8. Strategies to Overcome Split Incentive Tenant / Landlord Issues...

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

    Strategies to Overcome Split Incentive Tenant Landlord Issues Better Buildings Residential Network Multifamily and Low-Income Peer Exchange Call: Strategies to Overcome Split ...

  9. Two Electron Holes in Hematite Facilitate Water Splitting

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

    A molecular glance at water splitting. Hematite could play an important role in the generation of hydrogen by solar-powered water splitting, resulting in a truly...

  10. Field Monitoring Protocol: Mini-Split Heat Pumps

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

    ... Introduction The mini-split heat pump ... is termed a multi-split heat pump, and ... replacement system for electric resistance heating where natural gas is not available. ...

  11. Solar Water Splitting: Putting an Extra "Eye" on Surface Reactions...

    Office of Science (SC) Website

    Solar Water Splitting: Putting an Extra "Eye" on Surface Reactions that Store Sunlight as ... Solar Water Splitting: Putting an Extra "Eye" on Surface Reactions that Store Sunlight as ...

  12. Two Electron Holes in Hematite Facilitate Water Splitting

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

    Two Electron Holes in Hematite Facilitate Water Splitting Two Electron Holes in Hematite Facilitate Water Splitting Print Wednesday, 26 September 2012 00:00 Hydrogen is an...

  13. Strategies to Address Split Incentives in Multifamily Buildings...

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

    to Address Split Incentives in Multifamily Buildings Strategies to Address Split Incentives in Multifamily Buildings Better Buildings Neighborhood Program Multifamily Low-Income ...

  14. White Papers on Materials for Photoelectrochemical Water Splitting

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

    White Papers on Materials for Photoelectrochemical Water Splitting CONTENTS III-V Semiconductor Systems for High-Efficiency Solar Water Splitting Applications Todd Deutsch, Heli ...

  15. Advanced Water Splitting Materials Workshop | Department of Energy

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

    and Stanford University held the Advanced Water Splitting Materials Workshop on April ... and deployment of advanced water splitting technologies for renewable hydrogen production. ...

  16. Fossil analysis pushes back human split from other primates by...

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

    Fossil analysis pushes back human split from other primates Fossil analysis pushes back human split from other primates by two million years C. abyssinicus revealed answers about ...

  17. Quantum chaos in systems with ray splitting

    SciTech Connect (OSTI)

    Couchman, L. (Acoustics Division, Naval Research Laboratory, Washington, D.C. 20375 (United States)); Ott, E.; Antonsen, T.M. Jr. (Laboratory for Plasma Research, Department of Electrical Engineering, Department of Physics, University of Maryland, College Park, Maryland 20742 (United States))

    1992-11-15

    We consider wave systems in which rays split on reflection from sharp boundaries. Examples include the Schroedinger equation with the potential changing discontinuously across a surface, electromagnetic waves in a region with a discontinuous dielectric constant, elastic media with a clamped or free boundary, etc. By introducing a Monte Carlo treatment of the rays, it is possible to define chaotic rays via the standard Lyapunov number criterion. Numerical implementation of the Monte Carlo ray technique is carried out for the example of elastic media, and is utilized to investigate the extent to which these systems are globally ergodic. It is suggested that results from previous extensive work on quantum chaos without ray splitting can be extended to these ray splitting problems. In particular, we indicate a generalization of the Gutzwiller trace formula to cover ray splitting.

  18. Excitonic exchange splitting in bulk semiconductors

    SciTech Connect (OSTI)

    Fu, H.; Wang, L.; Zunger, A.

    1999-02-01

    We present an approach to calculate the excitonic fine-structure splittings due to electron-hole short-range exchange interactions using the local-density approximation pseudopotential method, and apply it to bulk semiconductors CdSe, InP, GaAs, and InAs. Comparing with previous theoretical results, the current calculated splittings agree well with experiments. Furthermore, we provide an approximate relationship between the short-range exchange splitting and the exciton Bohr radius, which can be used to estimate the exchange splitting for other materials. The current calculation indicates that a commonly used formula for exchange splitting in quantum dot is not valid. Finally, we find a very large pressure dependence of the exchange splitting: a factor of 4.5 increase as the lattice constant changes by 3.5{percent}. This increase is mainly due to the decrease of the Bohr radius via the change of electron effective mass. {copyright} {ital 1999} {ital The American Physical Society}

  19. DOE's Gasoline/Diesel PM Split Study | Department of Energy

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

    Gasoline/Diesel PM Split Study DOE's Gasoline/Diesel PM Split Study 2005 Diesel Engine Emissions Reduction (DEER) Conference Presentations and Posters 2005_deer_fujita.pdf (187.6 KB) More Documents & Publications DOE's Gasoline/Diesel PM Split Study DOE's Gasoline/Diesel PM Split Study Weekend/Weekday Ozone Study in the South Coast Air Basin

  20. Shear wave transducer for stress measurements in boreholes

    DOE Patents [OSTI]

    Mao, Nai-Hsien

    1987-01-01

    A technique and apparatus for estimating in situ stresses by measuring stress-induced velocity anisotropy around a borehole. Two sets each of radially and tangentially polarized transducers are placed inside the hole with displacement directions either parallel or perpendicular to the principal stress directions. With this configuration, relative travel times are measured by both a pulsed phase-locked loop technique and a cross correlation of digitized waveforms. The biaxial velocity data is used to back-calculate the applied stress.

  1. Ductless Mini-Split Air Conditioners | Department of Energy

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

    Ductless Mini-Split Air Conditioners Ductless Mini-Split Air Conditioners A ductless mini-split air conditioner is one solution to cooling part of a house. | Photo courtesy of ©iStockphoto/LUke1138. A ductless mini-split air conditioner is one solution to cooling part of a house. | Photo courtesy of ©iStockphoto/LUke1138. Ductless, mini split-system air-conditioners (mini splits) have numerous potential applications in residential, commercial, and institutional buildings. The most common

  2. Ductless, Mini-Split Heat Pumps | Department of Energy

    Energy Savers [EERE]

    Heat Pump Systems Ductless, Mini-Split Heat Pumps Ductless, Mini-Split Heat Pumps ... Learn More Heat pump systems Air-source heat pumps Geothermal heat pumps Absorption heat ...

  3. Ductless, Mini-Split Heat Pumps | Department of Energy

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

    remodel and your home does not have heating and cooling ducts, a ductless mini-split heat pump may be a cost-effective, energy-efficient choice. Ductless, mini-split-system heat...

  4. DOE's Gasoline/Diesel PM Split Study | Department of Energy

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

    More Documents & Publications DOE's GasolineDiesel PM Split Study DOE's GasolineDiesel PM Split Study Long-Term Changes in Gas- and Particle-Phase Emissions from On-Road Diesel ...

  5. Ductless Mini-Split Air Conditioners | Department of Energy

    Office of Environmental Management (EM)

    Mini-Split Air Conditioners A ductless mini-split air conditioner is one solution to cooling part of a house. | Photo courtesy of iStockphotoLUke1138. A ductless...

  6. A Novel Split-Cycle Engine | Department of Energy

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

    Splitting the Cycle the Right Way Splitting the Cycle the Right Way Improving Diesel Engine Sweet-spot Efficiency and Adapting it to Improve Duty-cycle MPG - plus Increasing ...

  7. Hydrogen Production: Thermochemical Water Splitting | Department of Energy

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

    Thermochemical Water Splitting Hydrogen Production: Thermochemical Water Splitting Thermochemical water splitting uses high temperatures-from concentrated solar power or from the waste heat of nuclear power reactions-and chemical reactions to produce hydrogen and oxygen from water. This is a long-term technology pathway, with potentially low or no greenhouse gas emissions. How Does It Work? Thermochemical water splitting processes use high-temperature heat (500°-2,000°C) to drive a series of

  8. Distributed Reforming of Renewable Liquids via Water Splitting...

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

    using Oxygen Transport Membrane (OTM) (Presentation) Distributed Reforming of Renewable Liquids via Water Splitting using Oxygen Transport Membrane (OTM) (Presentation) ...

  9. Two Electron Holes in Hematite Facilitate Water Splitting

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

    Two Electron Holes in Hematite Facilitate Water Splitting Two Electron Holes in Hematite Facilitate Water Splitting Print Wednesday, 26 September 2012 00:00 Hydrogen is an attractive form of fuel because its only by-product is nonpolluting water vapor. The problem, however, is that the production of hydrogen-via the process of water splitting-currently requires the burning of traditional fossil fuels. Therefore, water splitting by photoelectrochemical cells (PECs) fueled by solar power has long

  10. Heating and Cooling with Mini Splits in the Northeast

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

    buildingscience.com Heating and Cooling with Mini Splits in the Northeast Kohta Ueno October 23, 2014 2014 BA Webinar Mini Splits in Northeast 2 © buildingscience.com Background 2014 BA Webinar Mini Splits in Northeast 3 © buildingscience.com Overview  Transformations, Inc. currently building net-zero homes in Massachusetts  Mini split heat pumps (MSHPs) part of builder's strategy: tradeoff package  Single point of heating/ cooling on each floor  BA study of temperatures throughout

  11. DOE's Gasoline/Diesel PM Split Study

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

    DOE's Gasoline/Diesel PM Split Study Eric M. Fujita, David E. Campbell, William P. Arnott, Barbara Zielinska and Judith C. Chow Division of Atmospheric Sciences Desert Research Institute Reno, NV Douglas R. Lawson National Renewable Energy Laboratory Golden, CO 9 th Diesel Engine Emission Reduction (DEER) Workshop Newport, RI August 24-28, 2003 1 Acknowledgments Sponsor DOE's Office of FreedomCAR and Vehicle Technologies Dr. James Eberhardt Additional Support U.S. Environmental Protection Agency

  12. DOE's Gasoline/Diesel PM Split Study

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

    Gasoline/Diesel PM Split Study Douglas R. Lawson, National Renewable Energy Laboratory, Golden, CO Peter Gabele (retired), U.S. Environmental Protection Agency, Research Triangle Park, NC Richard Snow, BKI, Inc., Research Triangle Park, NC Nigel Clark, W. Scott Wayne, Ralph D. Nine, West Virginia University, Morgantown, WV Eric M. Fujita, Barbara Zielinska, William P. Arnott, David E. Campbell, John W. Walker, Hans Moosmüller, Desert Research Institute, Reno, NV Jamie Schauer, Charles

  13. TEMPORAL VARIATIONS OF FRACTURE DIRECTIONS AND FRACTURE DENSITIES...

    Open Energy Info (EERE)

    COSO GEOTHERMAL FIELD FROM ANALYSES OF SHEAR-WAVE SPLITTING. Proceedings of () ; () : PROCEEDINGS, Twenty-Seventh Workshop on Geothermal Reservoir Engineering Stanford...

  14. Flow Split Venturi, Axially-Rotated Valve

    DOE Patents [OSTI]

    Walrath, David E.; Lindberg, William R.; Burgess, Robert K.; LaBelle, James

    2000-02-22

    The present invention provides an axially-rotated valve which permits increased flow rates and lower pressure drop (characterized by a lower loss coefficient) by using an axial eccentric split venturi with two portions where at least one portion is rotatable with respect to the other portion. The axially-rotated valve typically may be designed to avoid flow separation and/or cavitation at full flow under a variety of conditions. Similarly, the valve is designed, in some embodiments, to produce streamlined flow within the valve. An axially aligned outlet may also increase the flow efficiency. A typical cross section of the eccentric split venturi may be non-axisymmetric such as a semicircular cross section which may assist in both throttling capabilities and in maximum flow capacity using the design of the present invention. Such a design can include applications for freeze resistant axially-rotated valves and may be fully-opened and fully-closed in one-half of a complete rotation. An internal wide radius elbow typically connected to a rotatable portion of the eccentric venturi may assist in directing flow with lower friction losses. A valve actuator may actuate in an axial manner yet be uniquely located outside of the axial flow path to further reduce friction losses. A seal may be used between the two portions that may include a peripheral and diametrical seal in the same plane. A seal separator may increase the useful life of the seal between the fixed and rotatable portions.

  15. Split Venturi, Axially-Rotated Valve

    DOE Patents [OSTI]

    Walrath, David E.; Lindberg, William R.; Burgess, Robert K.

    2000-08-29

    The present invention provides an axially-rotated valve which permits increased flow rates and lower pressure drop (characterized by a lower loss coefficient) by using an axial eccentric split venturi with two portions where at least one portion is rotatable with respect to the other portion. The axially-rotated valve typically may be designed to avoid flow separation and/or cavitation at full flow under a variety of conditions. Similarly, the valve is designed, in some embodiments, to produce streamlined flow within the valve. A typical cross section of the eccentric split venturi may be non-axisymmetric such as a semicircular cross section which may assist in both throttling capabilities and in maximum flow capacity using the design of the present invention. Such a design can include applications for freeze resistant axially-rotated valves and may be fully-opened and fully-closed in one-half of a complete rotation. An internal wide radius elbow typically connected to a rotatable portion of the eccentric venturi may assist in directing flow with lower friction losses. A valve actuator may actuate in an axial manner yet be uniquely located outside of the axial flow path to further reduce friction losses. A seal may be used between the two portions that may include a peripheral and diametrical seal in the same plane.

  16. Splitting of the Pygmy Dipole Resonance

    SciTech Connect (OSTI)

    Endres, J.; Zilges, A.; Butler, P.; Herzberg, R.-D.; Scheck, M.; Harakeh, M. N.; Harissopulos, S.; Lagoyannis, A.; Kruecken, R.; Ring, P.; Litvinova, E.; Pietralla, N.; Ponomarev, V. Yu.; Sonnabend, K.; Popescu, L.; Savran, D.; Stoica, V. I.; Woertche, H. J.

    2011-10-28

    In recent years investigations have been made to study the electric Pygmy Dipole Resonance (PDR) systematically, mainly in semi-magic nuclei. For this purpose the well understood high resolution ({gamma},{gamma}') photon scattering method is used. In complementary ({alpha},{alpha}'{gamma}) coincidence experiments at E{sub {alpha}} = 136 MeV a similar {gamma}-energy resolution and a high selectivity to E1 transitions can be obtained at the Big-Bite Spectrometer (BBS) at KVI, Groningen. In comparison to the ({gamma},{gamma}') method a structural splitting of the PDR is observed in the N = 82 nuclei {sup 138}Ba and {sup 140}Ce and in the Z = 50 nucleus {sup 124}Sn. The low energy part is excited in ({gamma},{gamma}') as well as in ({alpha},{alpha}'{gamma}) while the high energy part is observed in ({gamma},{gamma}') only. The experimental results together with theoretical QPM and RQTBA calculations on {sup 124}Sn which are able to reproduce the splitting of the PDR qualitatively are presented. The low-lying group of J{sup {pi}} = 1{sup -} states seem to represent the more isoscalar neutron-skin oscillation of the PDR while the energetically higher-lying states seemingly belong to the transitional region between the PDR and the isovector Giant Dipole Resonance (IVGDR).

  17. Strategies to Address Split Incentives in Multifamily Buildings |

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

    Department of Energy to Address Split Incentives in Multifamily Buildings Strategies to Address Split Incentives in Multifamily Buildings Better Buildings Neighborhood Program Multifamily / Low-Income Peer Exchange Call: Strategies to Address Split Incentives in Multifamily Buildings, Call Slides and Discussion Summary, April 26, 2012. Call Slides and Discussion Summary (546.02 KB) More Documents & Publications Outreach to Multifamily Landlords and Tenants Stewards of Affordable Housing

  18. Two Electron Holes in Hematite Facilitate Water Splitting

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

    Two Electron Holes in Hematite Facilitate Water Splitting Print Hydrogen is an attractive form of fuel because its only by-product is nonpolluting water vapor. The problem, however, is that the production of hydrogen-via the process of water splitting-currently requires the burning of traditional fossil fuels. Therefore, water splitting by photoelectrochemical cells (PECs) fueled by solar power has long been a primary goal of sustainable energy research. One roadblock to this goal is that the

  19. Two Electron Holes in Hematite Facilitate Water Splitting

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

    Two Electron Holes in Hematite Facilitate Water Splitting Print Hydrogen is an attractive form of fuel because its only by-product is nonpolluting water vapor. The problem, however, is that the production of hydrogen-via the process of water splitting-currently requires the burning of traditional fossil fuels. Therefore, water splitting by photoelectrochemical cells (PECs) fueled by solar power has long been a primary goal of sustainable energy research. One roadblock to this goal is that the

  20. Two Electron Holes in Hematite Facilitate Water Splitting

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

    Two Electron Holes in Hematite Facilitate Water Splitting Print Hydrogen is an attractive form of fuel because its only by-product is nonpolluting water vapor. The problem, however, is that the production of hydrogen-via the process of water splitting-currently requires the burning of traditional fossil fuels. Therefore, water splitting by photoelectrochemical cells (PECs) fueled by solar power has long been a primary goal of sustainable energy research. One roadblock to this goal is that the

  1. Two Electron Holes in Hematite Facilitate Water Splitting

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

    Two Electron Holes in Hematite Facilitate Water Splitting Print Hydrogen is an attractive form of fuel because its only by-product is nonpolluting water vapor. The problem, however, is that the production of hydrogen-via the process of water splitting-currently requires the burning of traditional fossil fuels. Therefore, water splitting by photoelectrochemical cells (PECs) fueled by solar power has long been a primary goal of sustainable energy research. One roadblock to this goal is that the

  2. Two Electron Holes in Hematite Facilitate Water Splitting

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

    Two Electron Holes in Hematite Facilitate Water Splitting Print Hydrogen is an attractive form of fuel because its only by-product is nonpolluting water vapor. The problem, however, is that the production of hydrogen-via the process of water splitting-currently requires the burning of traditional fossil fuels. Therefore, water splitting by photoelectrochemical cells (PECs) fueled by solar power has long been a primary goal of sustainable energy research. One roadblock to this goal is that the

  3. Enforcement Policy: Split-System Central Air Conditioners Without HSVC |

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

    Department of Energy Split-System Central Air Conditioners Without HSVC Enforcement Policy: Split-System Central Air Conditioners Without HSVC December 16, 2015 DOE issued an enforcement policy that it would begin investigating the methods manufacturers are using to rate split-system central air conditioners that do not have a highest sales volume combination (HSVC) to test as required by the applicable regulations and that it would assess penalties for units manufactured after February 1,

  4. Learning How Nature Uses Sunlight to Split Water

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

    Mn4Ca Structure. (click on image for diagram portraying the water-splitting catalytic cycle) Scientific Highlight LBNL Press Release Physical Biosciences, LBNL 30 November 2006 Learning How Nature Splits Water (Condensed by Brad Plummer from a press release issued by Lawrence Berkeley National Laboratory) Billions of years ago, primitive bacteria developed a way to harness sunlight to split water molecules into protons, electrons and oxygen-the cornerstone of photosynthesis. Now, a team of

  5. DOE - Office of Legacy Management -- WNI Split Rock Site - 043

    Office of Legacy Management (LM)

    Split Rock Site - 043 FUSRAP Considered Sites Site: WNI Split Rock Site (043) Active UMTRCA Title II site; when complete, site will be managed by LM Designated Name: Not Designated under FUSRAP Alternate Name: Split Rock, WY, Disposal Site Location: Fremont County, Wyoming Evaluation Year: Not considered for FUSRAP - in another program Site Operations: Disposal site Site Disposition: Remediation under UMTRCA Title II - site not ready to transition Radioactive Materials Handled: Yes Primary

  6. DOE - Office of Legacy Management -- WNI Split Rock Site - 043

    Office of Legacy Management (LM)

    Radioactive Materials Handled: Primary Radioactive Materials Handled: Radiological Survey(s): Site Status: The Western Nuclear, Inc. (WNI) Split Rock site is a Uranium Mill ...

  7. Designing spectrum-splitting dichroic filters to optimize current...

    Office of Scientific and Technical Information (OSTI)

    Title: Designing spectrum-splitting dichroic filters to optimize current-matched photovoltaics Authors: Miles, Alexander ; Cocilovo, Byron ; Wheelwright, Brian ; Pan, Wei ; Tweet, ...

  8. San Andreas Split Geothermal Region | Open Energy Information

    Open Energy Info (EERE)

    ENERGYGeothermal Home San Andreas Split Geothermal Region Details Areas (0) Power Plants (0) Projects (0) Techniques (0) Assessment of Moderate- and High-Temperature...

  9. Distributed Reforming of Renewable Liquids via Water Splitting...

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

    Water Splitting using Oxygen Transport Membrane (OTM) * U. (Balu) Balachandran, T. H. ... Objective & Rationale Objective: Develop compact dense ceramic membrane reactors that ...

  10. Two Electron Holes in Hematite Facilitate Water Splitting

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

    been suspected that in hematite, two different holes are formed with different water-splitting power. The existence of different types of holes with disparate reactivity...

  11. Enforcement Policy Statement: Split-System Central Air Conditioners...

    Energy Savers [EERE]

    Split-System Central Air Conditioners Without HSVC December 16, 2015 In the November 9, 2015 central air conditioner test procedure supplemental notice of proposed rulemaking (80 ...

  12. Two Electron Holes in Hematite Facilitate Water Splitting

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

    Two Electron Holes in Hematite Facilitate Water Splitting Print Hydrogen is an attractive form of fuel because its only by-product is nonpolluting water vapor. The problem,...

  13. Strategies to Overcome Split Incentive Tenant / Landlord Issues

    Broader source: Energy.gov [DOE]

    Better Buildings Residential Network Multifamily and Low-Income Peer Exchange Call: Strategies to Overcome Split Incentive Tenant / Landlord Issues, call slides and discussion summary, September 25, 2014.

  14. NREL Demonstrates Efficient Solar Water Splitting by Metal Oxide...

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

    Reference: Seabold, J.A.; Zhu, K.; Neale. N.R. (2014). "Efficient Solar Photoelectrolysis ... NRELFS-5900-61070 | January 2014 NREL Demonstrates Efficient Solar Water Splitting by ...

  15. Fast, Efficient Isothermal Redox to Split Water or Carbon Dioxide...

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

    Fast, Efficient Isothermal Redox to Split Water or Carbon Dioxide using Solar Energy ... the hercynite cycle allows faster, more efficient cycling and less wear on the equipment ...

  16. Ductless, Mini-Split Heat Pumps | Department of Energy

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

    Heat & Cool » Heat Pump Systems » Ductless, Mini-Split Heat Pumps Ductless, Mini-Split Heat Pumps Ductless, mini-split-system heat pumps (mini splits) make good retrofit add-ons to houses with "non-ducted" heating systems, such as hydronic (hot water heat), radiant panels, and space heaters (wood, kerosene, propane). They can also be a good choice for room additions where extending or installing distribution ductwork is not feasible, and very efficient new homes that require only

  17. Chapter 4, Small Commercial and Residential Unitary and Split...

    Office of Environmental Management (EM)

    Commercial and Residential Unitary and Split System HVAC Cooling Equipment-Efficiency Upgrade Evaluation Protocol David Jacobson, Jacobson Energy Research Subcontract Report NREL...

  18. Split-field pupil plane determination apparatus

    DOE Patents [OSTI]

    Salmon, Joseph T.

    1996-01-01

    A split-field pupil plane determination apparatus (10) having a wedge assembly (16) with a first glass wedge (18) and a second glass wedge (20) positioned to divide a laser beam (12) into a first laser beam half (22) and a second laser beam half (24) which diverge away from the wedge assembly (16). A wire mask (26) is positioned immediately after the wedge assembly (16) in the path of the laser beam halves (22, 24) such that a shadow thereof is cast as a first shadow half (30) and a second shadow half (32) at the input to a relay telescope (14). The relay telescope (14) causes the laser beam halves (22, 24) to converge such that the first shadow half (30) of the wire mask (26) is aligned with the second shadow half (32) at any subsequent pupil plane (34).

  19. Split driveshaft pump for hazardous fluids

    DOE Patents [OSTI]

    Evans, II, Thomas P.; Purohit, Jwalit J.; Fazio, John M.

    1995-01-01

    A pump having a split driveshaft for use in pumping hazardous fluids wherein only one driveshaft becomes contaminated by the fluid while the second remains isolated from the fluid. The pump has a first portion and a second portion. The first portion contains a pump motor, the first driveshaft, a support pedestal, and vapor barriers and seals. The second portion contains a second, self-lubricating driveshaft and an impeller. The first and second driveshafts are connected together by a releasable coupling. A shield and a slinger deployed below the coupling prevent fluid from the second portion from reaching the first portion. In operation, only the second assembly comes into contact with the fluid being pumped, so the risk of contamination of the first portion by the hazardous fluid is reduced. The first assembly can be removed for repairs or routine maintenance by decoupling the first and second driveshafts and disconnecting the motor from the casing.

  20. DOE's Gasoline/Diesel PM Split Study | Department of Energy

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

    4 Diesel Engine Emissions Reduction (DEER) Conference Presentation: National Renewable Energy Laboratory 2004_deer_lawson.pdf (275.38 KB) More Documents & Publications DOE's Gasoline/Diesel PM Split Study DOE's Gasoline/Diesel PM Split Study Collaborative Lubricating Oil Study on Emissions (CLOSE) Project

  1. Open-split interface for mass spectrometers

    DOE Patents [OSTI]

    Diehl, John W.

    1991-01-01

    An open-split interface includes a connector body having four leg members projecting therefrom within a single plane, the first and third legs being coaxial and the second and fourth legs being coaxial. A tubular aperture extends through the first and third legs and a second tubular aperture extends through the second and fourth legs, connecting at a juncture within the center of the connector body. A fifth leg projects from the connector body and has a third tubular aperture extending therethrough to the juncture of the first and second tubular apertures. A capillary column extends from a gas chromatograph into the third leg with its end adjacent the juncture. A flow restrictor tube extends from a mass spectrometer through the first tubular aperture in the first and third legs and into the capillary columnm end, so as to project beyond the end of the third leg within the capillary column. An annular gap between the tube and column allows excess effluent to pass to the juncture. A pair of short capillary columns extend from separate detectors into the second tubular aperture in the second and fourth legs, and are oriented with their ends spaced slightly from the first capillary column end. A sweep flow tube is mounted in the fifth leg so as to supply a helium sweep flow to the juncture.

  2. Thermoelectric-induced unitary Cooper pair splitting efficiency

    SciTech Connect (OSTI)

    Cao, Zhan; Fang, Tie-Feng; Li, Lin; Luo, Hong-Gang

    2015-11-23

    Thermoelectric effect is exploited to optimize the Cooper pair splitting efficiency in a Y-shaped junction, which consists of two normal leads coupled to an s-wave superconductor via double noninteracting quantum dots. Here, utilizing temperature difference rather than bias voltage between the two normal leads, and tuning the two dot levels such that the transmittance of elastic cotunneling process is particle-hole symmetric, we find current flowing through the normal leads are totally contributed from the splitting of Cooper pairs emitted from the superconductor. Such a unitary splitting efficiency is significantly better than the efficiencies obtained in experiments so far.

  3. Field Monitoring Protocol: Mini-Split Heat Pumps

    SciTech Connect (OSTI)

    Christensen, D.; Fang, X.; Tomerlin, J.; Winkler, J.; Hancock, E.

    2011-03-01

    The report provides a detailed method for accurately measuring and monitoring performance of a residential Mini-Split Heat Pump. It will be used in high-performance retrofit applications, and as part of DOE's Building America residential research program.

  4. Field Monitoring Protocol. Mini-Split Heat Pumps

    SciTech Connect (OSTI)

    Christensen, Dane; Fang, Xia; Tomerlin, Jeff; Winkler, Jon; Hancock, E.

    2011-03-01

    This Building America program report provides a detailed method for accurately measuring and monitoring performance of a residential mini-split heat pump, which will be used in high-performance retrofit applications.

  5. Towards a Design of a Complete Solar Water Splitting System

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

    Towards a Design of a Complete Solar Water Splitting System 1 Feb 2013 BISfuel : A team of Bisfuel researchers led by Devens Gust, Ana Moore and Tom Moore has designed and ...

  6. Two Electron Holes in Hematite Facilitate Water Splitting

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

    by-product is nonpolluting water vapor. The problem, however, is that the production of hydrogen-via the process of water splitting-currently requires the burning of traditional...

  7. Splitting the Cycle the Right Way | Department of Energy

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

    The unique opposed-cylinder configuration of the TourEngine allows superior thermal management and efficient gas transfer compared to other split-cycle designs. p-19_tour.pdf (239.27

  8. Mini-Split Heat Pumps Multifamily Retrofit Feasibility Study

    SciTech Connect (OSTI)

    Dentz, Jordan; Podorson, David; Varshney, Kapil

    2014-05-01

    Mini-split heat pumps can provide space heating and cooling in many climates and are relatively affordable. These and other features make them potentially suitable for retrofitting into multifamily buildings in cold climates to replace electric resistance heating or other outmoded heating systems. This report investigates the suitability of mini-split heat pumps for multifamily retrofits. Various technical and regulatory barriers are discussed and modeling was performed to compare long-term costs of substituting mini-splits for a variety of other heating and cooling options. A number of utility programs have retrofit mini-splits in both single family and multifamily residences. Two such multifamily programs are discussed in detail.

  9. White Papers on Materials for Photoelectrochemical Water Splitting |

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

    Department of Energy White Papers on Materials for Photoelectrochemical Water Splitting White Papers on Materials for Photoelectrochemical Water Splitting Series of white papers from the U.S. Department of Energy Photoelectrochemical Working Group (Revision: October 2013). These white papers are intended as concise living documents summarizing the unique potential and challenges faced in the R&D of promising materials classes. pec_white_papers.pdf (4.26 MB) More Documents &

  10. Distributed Reforming of Renewable Liquids via Water Splitting using Oxygen

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

    Transport Membrane (OTM) (Presentation) | Department of Energy Renewable Liquids via Water Splitting using Oxygen Transport Membrane (OTM) (Presentation) Distributed Reforming of Renewable Liquids via Water Splitting using Oxygen Transport Membrane (OTM) (Presentation) Presented at the 2007 Bio-Derived Liquids to Hydrogen Distributed Reforming Working Group held November 6, 2007 in Laurel, Maryland. 11_anl_distributed_reforming_using_otm.pdf (809.59 KB) More Documents & Publications Cost

  11. Enabling unassisted solar water splitting by iron oxide and silicon

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

    Jang, Ji-Wook; Du, Chun; Ye, Yifan; Lin, Yongjing; Yao, Xiahui; Thorne, James; Liu, Erik; McMahon, Gregory; Zhu, Junfa; Javey, Ali; et al

    2015-06-16

    A solution for large-scale solar energy storage is photoelectrochemical (PEC) water splitting. However, its development has been impeded by the poor performance of photoanodes, particularly in their capability for photovoltage generation. Many examples employing photovoltaic modules to correct the deficiency for unassisted solar water splitting have been reported to-date. We show that, by using the prototypical photoanode material of haematite as a study tool, structural disorders on or near the surfaces are important causes of the low photovoltages. We develop a facile re-growth strategy to reduce surface disorders and as a consequence, a turn-on voltage of 0.45 V (versus reversiblemore » hydrogen electrode) is achieved. In conclusion, this result permits us to construct a photoelectrochemical device with a haematite photoanode and Si photocathode to split water at an overall efficiency of 0.91%, with NiFeOx and TiO2/Pt overlayers, respectively.« less

  12. Crystal Splitting in the Growth of Bi2S3

    SciTech Connect (OSTI)

    Tang, Jing; Alivisatos, A. Paul

    2006-06-15

    Novel Bi{sub 2}S{sub 3} nanostructures with a sheaf-like morphology are obtained via reaction of bismuth acetate-oleic acid complex with elemental sulfur in 1-octadecence. We propose these structures form by the splitting crystal growth mechanism, which is known to account for the morphology some mineral crystals assume in nature. By controlling the synthetic parameters, different forms of splitting, analogous to observed in minerals, are obtained in our case of Bi{sub 2}S{sub 3}. These new and complex Bi{sub 2}S{sub 3} nanostructures are characterized by TEM, SEM, XRD and ED.

  13. Higgs, Binos and Gluinos: Split Susy within Reach

    SciTech Connect (OSTI)

    Alves, Daniele S.M.; Izaguirre, Eder; Wacker, Jay G.; /SLAC /Stanford U., ITP

    2012-09-14

    Recent results from the LHC for the Higgs boson with mass between 142 GeV {approx}< m{sub h{sup 0}} {approx}< 147 GeV points to PeV-scale Split Supersymmetry. This article explores the consequences of a Higgs mass in this range and possible discovery modes for Split Susy. Moderate lifetime gluinos, with decay lengths in the 25 {micro}m to 10 yr range, are its imminent smoking gun signature. The 7TeV LHC will be sensitive to the moderately lived gluinos and trilepton signatures from direct electroweakino production. Moreover, the dark matter abundance may be obtained from annihilation through an s-channel Higgs resonance, with the LSP almost purely bino and mass m{sub {chi}{sub 1}{sup 0}} {approx_equal} 70 GeV. The Higgs resonance region of Split Susy has visible signatures in dark matter direct and indirect detection and electric dipole moment experiments. If the anomalies go away, the majority of Split Susy parameter space will be excluded.

  14. Ductless Mini-Split Heat Pump Comfort Evaluation

    SciTech Connect (OSTI)

    Roth, K.; Sehgal, N.; Akers, C.

    2013-03-01

    Field tests were conducted in two homes in Austin, TX to evaluate the comfort performance of ductless mini-split heat pumps (DMSHPs), measuring temperature and relative humidity measurements in four rooms in each home before and after retrofitting a central HVAC system with DMSHPs.

  15. DOE Technical Targets for Hydrogen Production from Photoelectrochemical Water Splitting

    Broader source: Energy.gov [DOE]

    These tables list the U.S. Department of Energy (DOE) technical targets and example cost and performance parameter values that achieve the targets for hydrogen production from photoelectrochemical water splitting. The tables are organized into separate sections for photoelectrode systems and dual bed photocatalyst systems.

  16. Protein subcellular localization assays using split fluorescent proteins

    DOE Patents [OSTI]

    Waldo, Geoffrey S.; Cabantous, Stephanie

    2009-09-08

    The invention provides protein subcellular localization assays using split fluorescent protein systems. The assays are conducted in living cells, do not require fixation and washing steps inherent in existing immunostaining and related techniques, and permit rapid, non-invasive, direct visualization of protein localization in living cells. The split fluorescent protein systems used in the practice of the invention generally comprise two or more self-complementing fragments of a fluorescent protein, such as GFP, wherein one or more of the fragments correspond to one or more beta-strand microdomains and are used to "tag" proteins of interest, and a complementary "assay" fragment of the fluorescent protein. Either or both of the fragments may be functionalized with a subcellular targeting sequence enabling it to be expressed in or directed to a particular subcellular compartment (i.e., the nucleus).

  17. Optimization of the main parameters of miniature split Stirling cooler

    SciTech Connect (OSTI)

    Tsesarsky, J.

    1995-12-01

    Unlike other modern industrial products Stirling refrigerators development is based mainly on experimental methods. Newly developed high accuracy numerical model for Stirling refrigerators analysis provides good approximation of gas stream process assured by large number of nodes placed in regenerator (300) and large number of time steps (240 per one machine turn). Confidence in accuracy of equations solution makes possible Stirling coolers optimization. In addition to information about refrigerator temperature field the model provides information about driving force of split cooler displacer for computer aided design of displacer driver. In this paper, four parameters of split Stirling refrigerator are optimized: compressor-expander swept volume ratio; phase angle; regenerator length; and regenerator diameter. In each program run power delivered to gas was kept constant by continuous correction of compressor and expander strokes without changing their ratio. Collection of the results produce the optimum cooler structure. Driving displacer force-theta function is also available.

  18. Permanent split capacitor single phase electric motor system

    DOE Patents [OSTI]

    Kirschbaum, Herbert S.

    1984-01-01

    A permanent split capacitor single phase electric motor achieves balanced operation at more than one operating point by adjusting the voltage supplied to the main and auxiliary windings and adjusting the capacitance in the auxiliary winding circuit. An intermediate voltage tap on an autotransformer supplies voltage to the main winding for low speed operation while a capacitive voltage divider is used to adjust the voltage supplied to the auxiliary winding for low speed operation.

  19. Permanent split capacitor single phase electric motor system

    DOE Patents [OSTI]

    Kirschbaum, H.S.

    1984-08-14

    A permanent split capacitor single phase electric motor achieves balanced operation at more than one operating point by adjusting the voltage supplied to the main and auxiliary windings and adjusting the capacitance in the auxiliary winding circuit. An intermediate voltage tap on an autotransformer supplies voltage to the main winding for low speed operation while a capacitive voltage divider is used to adjust the voltage supplied to the auxiliary winding for low speed operation. 4 figs.

  20. Internal/External Split Field Generator - Energy Innovation Portal

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

    Internal/External Split Field Generator Oak Ridge National Laboratory Contact ORNL About This Technology Technology Marketing SummaryThese technologies are designs and methods that boost the efficiency of electric generators by decoupling the magnetic polarity of the driving mechanism while increasing the operational frequency of the machine. Both are unique, low cost methods to develop a generator with a higher power density.DescriptionCommercial applications include stationary, rotational or

  1. Rational design of a split-Cas9 enzyme complex

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

    Wright, Addison V.; Sternberg, Samuel H.; Taylor, David W.; Staahl, Brett T.; Bardales, Jorge A.; Kornfeld, Jack E.; Doudna, Jennifer A.

    2015-02-23

    Cas9, an RNA-guided DNA endonuclease found in clustered regularly interspaced short palindromic repeats (CRISPR) bacterial immune systems, is a versatile tool for genome editing, transcriptional regulation, and cellular imaging applications. Structures of Streptococcus pyogenes Cas9 alone or bound to single-guide RNA (sgRNA) and target DNA revealed a bilobed protein architecture that undergoes major conformational changes upon guide RNA and DNA binding. To investigate the molecular determinants and relevance of the interlobe rearrangement for target recognition and cleavage, we designed a split-Cas9 enzyme in which the nuclease lobe and α-helical lobe are expressed as separate polypeptides. The lobes do not interactmore » on their own, the sgRNA recruits them into a ternary complex that recapitulates the activity of full-length Cas9 and catalyzes site-specific DNA cleavage. The use of a modified sgRNA abrogates split-Cas9 activity by preventing dimerization, allowing for the development of an inducible dimerization system. We propose that split-Cas9 can act as a highly regulatable platform for genome-engineering applications.« less

  2. Rational design of a split-Cas9 enzyme complex

    SciTech Connect (OSTI)

    Wright, Addison V.; Sternberg, Samuel H.; Taylor, David W.; Staahl, Brett T.; Bardales, Jorge A.; Kornfeld, Jack E.; Doudna, Jennifer A.

    2015-02-23

    Cas9, an RNA-guided DNA endonuclease found in clustered regularly interspaced short palindromic repeats (CRISPR) bacterial immune systems, is a versatile tool for genome editing, transcriptional regulation, and cellular imaging applications. Structures of Streptococcus pyogenes Cas9 alone or bound to single-guide RNA (sgRNA) and target DNA revealed a bilobed protein architecture that undergoes major conformational changes upon guide RNA and DNA binding. To investigate the molecular determinants and relevance of the interlobe rearrangement for target recognition and cleavage, we designed a split-Cas9 enzyme in which the nuclease lobe and ?-helical lobe are expressed as separate polypeptides. The lobes do not interact on their own, the sgRNA recruits them into a ternary complex that recapitulates the activity of full-length Cas9 and catalyzes site-specific DNA cleavage. The use of a modified sgRNA abrogates split-Cas9 activity by preventing dimerization, allowing for the development of an inducible dimerization system. We propose that split-Cas9 can act as a highly regulatable platform for genome-engineering applications.

  3. Nanoscale Strontium Titanate Photocatalysts for Overall Water Splitting

    SciTech Connect (OSTI)

    Townsend, Troy K.; Browning, Nigel D.; Osterloh, Frank

    2012-08-28

    SrTiO3 (STO) is a large band gap (3.2 eV) semiconductor that catalyzes the overall water splitting reaction under UV light irradiation in the presence of a NiO cocatalyst. As we show here, the reactivity persists in nanoscale particles of the material, although the process is less effective at the nanoscale. To reach these conclusions, Bulk STO, 30 5 nm STO, and 6.5 1 nm STO were synthesized by three different methods, their crystal structures verified with XRD and their morphology observed with HRTEM before and after NiO deposition. In connection with NiO, all samples split water into stoichiometric mixtures of H2 and O2, but the activity is decreasing from 28 ?mol H2 g1 h1 (bulk STO), to 19.4 ?mol H2 g1 h1 (30 nm STO), and 3.0 ?mol H2 g1 h1 (6.5 nm STO). The reasons for this decrease are an increase of the water oxidation overpotential for the smaller particles and reduced light absorption due to a quantum size effect. Overall, these findings establish the first nanoscale titanate photocatalyst for overall water splitting.

  4. Microearthquake Technology for EGS Fracture Characterization

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

    ... Application of hypocc with absolute constraints to data from Coso * February 2005 MEQs near injection well 34-9RD2 3 iterations 9 iterations 9 iter + absolute 13 | US DOE ...

  5. Micro-Earthquake | Open Energy Information

    Open Energy Info (EERE)

    as well as fluid expansioncompression. Measurement of microseismicity can aid in the management of reinjection during the production of the geothermal field. Levels of...

  6. Microearthquake Technology for EGS Fracture Characterization...

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

    Engineered Geothermal System through Hydraulic and Thermal Stimulation Integration of Noise and Coda Correlation Data into Kinematic and Waveform Inversions Newberry EGS...

  7. Microearthquake Technology for EGS Fracture Characterization

    Broader source: Energy.gov [DOE]

    Project objectives: To understand how EGS fracture networks develop; To develop technology to determine accurate absolute three-dimensional positions of EGS fracture networks.

  8. Preconceptual design of a salt splitting process using ceramic membranes

    SciTech Connect (OSTI)

    Kurath, D.E.; Brooks, K.P.; Hollenberg, G.W.; Clemmer, R.; Balagopal, S.; Landro, T.; Sutija, D.P.

    1997-01-01

    Inorganic ceramic membranes for salt splitting of radioactively contaminated sodium salt solutions are being developed for treating U. S. Department of Energy tank wastes. The process consists of electrochemical separation of sodium ions from the salt solution using sodium (Na) Super Ion Conductors (NaSICON) membranes. The primary NaSICON compositions being investigated are based on rare- earth ions (RE-NaSICON). Potential applications include: caustic recycling for sludge leaching, regenerating ion exchange resins, inhibiting corrosion in carbon-steel tanks, or retrieving tank wastes; reducing the volume of low-level wastes volume to be disposed of; adjusting pH and reducing competing cations to enhance cesium ion exchange processes; reducing sodium in high-level-waste sludges; and removing sodium from acidic wastes to facilitate calcining. These applications encompass wastes stored at the Hanford, Savannah River, and Idaho National Engineering Laboratory sites. The overall project objective is to supply a salt splitting process unit that impacts the waste treatment and disposal flowsheets and meets user requirements. The potential flowsheet impacts include improving the efficiency of the waste pretreatment processes, reducing volume, and increasing the quality of the final waste disposal forms. Meeting user requirements implies developing the technology to the point where it is available as standard equipment with predictable and reliable performance. This report presents two preconceptual designs for a full-scale salt splitting process based on the RE-NaSICON membranes to distinguish critical items for testing and to provide a vision that site users can evaluate.

  9. Split ring floating air riding seal for a turbine

    SciTech Connect (OSTI)

    Mills, Jacob A

    2015-11-03

    A floating air riding seal for a gas turbine engine with a rotor and a stator, an annular piston chamber with an axial moveable annular piston assembly within the annular piston chamber, an annular cavity formed on the annular piston assembly that faces a seal surface on the rotor, and a central passage connecting the annular cavity to the annular piston chamber to supply compressed air to the seal face, where the annular piston assembly is a split piston assembly to maintain a tight seal as coning of the rotor disk occurs.

  10. Systems and methods for displaying data in split dimension levels

    DOE Patents [OSTI]

    Stolte, Chris; Hanrahan, Patrick

    2015-07-28

    Systems and methods for displaying data in split dimension levels are disclosed. In some implementations, a method includes: at a computer, obtaining a dimensional hierarchy associated with a dataset, wherein the dimensional hierarchy includes at least one dimension and a sub-dimension of the at least one dimension; and populating information representing data included in the dataset into a visual table having a first axis and a second axis, wherein the first axis corresponds to the at least one dimension and the second axis corresponds to the sub-dimension of the at least one dimension.

  11. AN ARECIBO SURVEY FOR ZEEMAN SPLITTING IN OH MEGAMASER GALAXIES

    SciTech Connect (OSTI)

    McBride, James; Heiles, Carl E-mail: heiles@astro.berkeley.edu

    2013-01-20

    We present the results of a comprehensive survey using the Arecibo Observatory for Zeeman splitting of OH lines in OH megamasers (OHMs). A total of 77 sources were observed with the Arecibo telescope. Of these, maser emission could not be detected for eight sources, and two sources were only ambiguously detected. Another 27 sources were detected at low signal-to-noise ratios or with interference that prevented placing any useful limits on the presence of magnetic fields. In 26 sources, it was possible to place upper limits on the magnitude of magnetic fields, typically between 10 and 30 mG. For 14 sources, the Stokes V spectra exhibit features consistent with Zeeman splitting. Eleven of these 14 are new detections, and the remaining three are re-detections of Stokes V detections in Robishaw et al. Among confident new detections, we derive magnetic fields associated with maser regions with magnitudes ranging from 6.1 to 27.6 mG. The distribution of magnetic field strengths suggests the magnetic fields in OH masing clouds in OHMs are larger than those in Galactic OH masers. The results are consistent with magnetic fields playing a dynamically important role in OH masing clouds in OHMs.

  12. Closing the Circle on the Splitting of the Atom | Department of Energy

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

    Closing the Circle on the Splitting of the Atom Closing the Circle on the Splitting of the Atom This report was the first report published in the new Departmental era of openness that described existing environmental, safety, and health problems throughout the nuclear weapons complex and the cleanup challenges that DOE faced. It also provided initial plans for what DOE was doing to address these problems. Closing the Circle on the Splitting of the Atom (4.77 MB) More Documents & Publications

  13. Spin rotators and split Siberian Snakes (Journal Article) | SciTech...

    Office of Scientific and Technical Information (OSTI)

    Journal Article: Spin rotators and split Siberian Snakes Citation Details In-Document ... DOE Contract Number: AC02-98CH10886 Resource Type: Journal Article Resource Relation: ...

  14. Process and apparatus for split feed of spent catalyst to high...

    Office of Scientific and Technical Information (OSTI)

    Title: Process and apparatus for split feed of spent catalyst to high efficiency catalyst regenerator This patent describes a fluidized catalytic cracking process for catalytic ...

  15. Isoscalar and Isovector Splitting of Pygmy Dipole Structures

    SciTech Connect (OSTI)

    Paar, N.; Vretenar, D.; Niu, Y. F.; Meng, J.

    2009-07-17

    The electric-dipole response of {sup 140}Ce is investigated using the fully consistent relativistic quasiparticle random phase approximation. By analyzing the isospin structure of the E1 response, it is shown that the low-energy (pygmy) strength separates into two segments with different isospin character. The more pronounced pygmy structure at lower energy is composed of predominantly isoscalar states with surface-peaked transition densities. At somewhat higher energy the calculated E1 strength is primarily of isovector character, as expected for the low-energy tail of the giant dipole resonance. The results are in qualitative agreement with those obtained in recent (gamma, gamma{sup '}) and (alpha, alpha{sup '}gamma) experiments, and provide a simple explanation for the splitting of low-energy E1 strength into two groups of states with different isospin structure and radial dependence of the corresponding transition densities.

  16. Conducting a 3D Converted Shear Wave Project to Reduce Exploration Risk at Wister, CA

    SciTech Connect (OSTI)

    Matlick, Skip; Walsh, Patrick; Rhodes, Greg; Fercho, Steven

    2015-06-30

    Ormat sited 2 full-size exploration wells based on 3D seismic interpretation of fractures, prior drilling results, and temperature anomaly. The wells indicated commercial temperatures (>300 F), but almost no permeability, despite one of the wells being drilled within 820 ft of an older exploration well with reported indications of permeability. Following completion of the second well in 2012, Ormat undertook a lengthy program to 1) evaluate the lack of observed permeability, 2) estimate the likelihood of finding permeability with additional drilling, and 3) estimate resource size based on an anticipated extent of permeability.

  17. Shear wave experiments at the US site at the Grimsel laboratory

    SciTech Connect (OSTI)

    Majer, E.L.; Peterson, J.E. Jr. ); Bluemling, P.; Sattel, G. )

    1990-07-01

    As part of the United States Department of Energy (USDOE) cooperative project with the National Cooperative for the Storage of Radioactive Waste (Nagra) of Switzerland, there have been a series of studies carried out at the Nagra underground test facility at Grimsel. The Grimsel test facility is several 3.5 meter diameter tunnels excavated with a tunnel boring machine in the southern Swiss Alps. The rock type is granitic, although there is a large variation in the granitic fabric throughout the facility. The work described here was the first phase of a multiyear project to evaluate and develop seismic imaging techniques for fracture detection and characterization for the use in siting underground nuclear waste facilities. Data from a crosshole tomographic survey in the Underground Seismic (US) site at the Nagra Grimsel test facility in Switzerland and successfully reprocessed to enhance the S-wave arrivals. The results indicate that in a saturated granite Vp/Vs ratios approach 2.0 in the fractured rock. These results indicate that S-wave data would be very useful for fracture detection, especially in detecting thinner fractures.

  18. New experimental techniques with the split Hopkinson pressure bar

    SciTech Connect (OSTI)

    Frantz, C.E.; Follansbee, P.S.; Wright, W.J.

    1984-01-01

    The split Hopkinson pressure bar or Kolsky bar has provided for many years a technique for performing compression tests at strain rates approaching 10/sup 4/ s/sup -1/. At these strain rates, the small dimensions possible in a compression test specimen give an advantage over a dynamic tensile test by allowing the stress within the specimen to equilibrate within the shortest possible time. The maximum strain rates possible with this technique are limited by stress wave propagation in the elastic pressure bars as well as in the deforming specimen. This subject is reviewed in this paper, and it is emphasized that a slowly rising excitation is preferred to one that rises steeply. Experimental techniques for pulse shaping and a numerical procedure for correcting the raw data for wave dispersion in the pressure bars are presented. For tests at elevated temperature a bar mover apparatus has been developed which effectively brings the cold pressure bars into contact with the specimen, which is heated with a specially designed furnace, shortly before the pressure wave arrives. This procedure has been used successfully in tests at temperatures as high as 1000/sup 0/C.

  19. Electro-optic voltage sensor with beam splitting

    DOE Patents [OSTI]

    Woods, Gregory K.; Renak, Todd W.; Davidson, James R.; Crawford, Thomas M.

    2002-01-01

    The invention is a miniature electro-optic voltage sensor system capable of accurate operation at high voltages without use of the dedicated voltage dividing hardware typically found in the prior art. The invention achieves voltage measurement without significant error contributions from neighboring conductors or environmental perturbations. The invention employs a transmitter, a sensor, a detector, and a signal processor. The transmitter produces a beam of electromagnetic radiation which is routed into the sensor. Within the sensor the beam undergoes the Pockels electro-optic effect. The electro-optic effect produces a modulation of the beam's polarization, which is in turn converted to a pair of independent conversely-amplitude-modulated signals, from which the voltage of the E-field is determined by the signal processor. The use of converse AM signals enables the signal processor to better distinguish signal from noise. The sensor converts the beam by splitting the beam in accordance with the axes of the beam's polarization state (an ellipse) into at least two AM signals. These AM signals are fed into a signal processor and processed to determine the voltage between a ground conductor and the conductor on which voltage is being measured.

  20. Electro-optic voltage sensor with Multiple Beam Splitting

    DOE Patents [OSTI]

    Woods, Gregory K.; Renak, Todd W.; Crawford, Thomas M.; Davidson, James R.

    2000-01-01

    A miniature electro-optic voltage sensor system capable of accurate operation at high voltages without use of the dedicated voltage dividing hardware. The invention achieves voltage measurement without significant error contributions from neighboring conductors or environmental perturbations. The invention employs a transmitter, a sensor, a detector, and a signal processor. The transmitter produces a beam of electromagnetic radiation which is routed into the sensor. Within the sensor the beam undergoes the Pockels electro-optic effect. The electro-optic effect produces a modulation of the beam's polarization, which is in turn converted to a pair of independent conversely-amplitude-modulated signals, from which the voltage of the E-field is determined by the signal processor. The use of converse AM signals enables the signal processor to better distinguish signal from noise. The sensor converts the beam by splitting the beam in accordance with the axes of the beam's polarization state (an ellipse) into at least two AM signals. These AM signals are fed into a signal processor and processed to determine the voltage between a ground conductor and the conductor on which voltage is being measured.

  1. Laboratory Test Report for Fujitsu 12RLS and Mitsubishi FE12NA Mini-Split Heat Pumps

    SciTech Connect (OSTI)

    Winkler, Jon

    2011-09-01

    Mini-split heat pumps are being proposed as a new retrofit option to replace resistance heating in the Pacific Northwest. NREL has previously developed a field test protocol for mini-split systems to ensure consistent results from field tests. This report focuses on the development of detailed system performance maps for mini-split heat pumps so that the potential benefits of mini-split systems can be accurately analyzed for different climate regions and housing types.

  2. TEMPORAL SPECTRAL SHIFT AND POLARIZATION OF A BAND-SPLITTING SOLAR TYPE II RADIO BURST

    SciTech Connect (OSTI)

    Du, Guohui; Chen, Yao; Lv, Maoshui; Kong, Xiangliang; Feng, Shiwei; Guo, Fan; Li, Gang

    2014-10-01

    In many type II solar radio bursts, the fundamental and/or the harmonic branches of the bursts can split into two almost parallel bands with similar spectral shapes and frequency drifts. However, the mechanisms accounting for this intriguing phenomenon remain elusive. In this study, we report a special band-splitting type II event in which spectral features appear systematically earlier on the upper band (with higher frequencies) than on the lower band (with lower frequencies) by several seconds. Furthermore, the emissions carried by the splitting band are moderately polarized with the left-hand polarized signals stronger than the right-hand ones. The polarization degree varies in a range of 0.3 to 0.6. These novel observational findings provide important constraints on the underlying physical mechanisms of band-splitting of type II radio bursts.

  3. Design and demonstration of a spectrum-splitting photovoltaic concentrator module

    SciTech Connect (OSTI)

    Borden, P.G.; Gregory, P.E.; Moore, O.E.

    1982-11-01

    A spectrum splitting, concentrating photovoltaic module has been designed and fabricated that uses point focus curved facet Fresnel lenses to concentrate incident sunlight. The concentrated sunlight beam spectrum is split into a high and low energy part by a dichroic filter. The high energy part of the spectrum is transmitted to an AlGaAs solar cell and the low energy part is reflected to a Si cell. Spectrum splitting and using cells that respond best to the two parts of the spectrum splitting and using cells that respond best to the two parts of the spectrum gives a higher efficiency than the use of either cell alone. The experimental module has been tested which consists of 10 AlGaAs and 10 Si cells, and a sunlight to electricity conversion efficiency of 20% has been measured.

  4. Giant and tunable valley degeneracy splitting in MoTe 2 (Journal...

    Office of Scientific and Technical Information (OSTI)

    This content will become publicly available on September 7, 2016 Title: Giant and tunable valley degeneracy splitting in MoTe 2 Authors: Qi, Jingshan ; Li, Xiao ; Niu, Qian ; Feng, ...

  5. Replacing Resistance Heating with Mini-Split Heat Pumps, Sharon, Connecticut (Fact Sheet)

    SciTech Connect (OSTI)

    Not Available

    2014-05-01

    Mini-split heat pumps can provide space heating and cooling in many climates and are relatively affordable. These and other features make them potentially suitable for retrofitting into multifamily buildings in cold climates to replace electric resistance heating or other outmoded heating systems. This report investigates the suitability of mini-split heat pumps for multifamily retrofits. Various technical and regulatory barriers are discussed and modeling was performed to compare long-term costs of substituting mini-splits for a variety of other heating and cooling options. A number of utility programs have retrofit mini-splits in both single family and multifamily residences. Two such multifamily programs are discussed in detail.

  6. Solar High Temperature Water-Splitting Cycle with Quantum Boost

    SciTech Connect (OSTI)

    Taylor, Robin; Davenport, Roger; Talbot, Jan; Herz, Richard; Genders, David; Symons, Peter; Brown, Lloyd

    2014-04-25

    A sulfur family chemical cycle having ammonia as the working fluid and reagent was developed as a cost-effective and efficient hydrogen production technology based on a solar thermochemical water-splitting cycle. The sulfur ammonia (SA) cycle is a renewable and sustainable process that is unique in that it is an all-fluid cycle (i.e., with no solids handling). It uses a moderate temperature solar plant with the solar receiver operating at 800°C. All electricity needed is generated internally from recovered heat. The plant would operate continuously with low cost storage and it is a good potential solar thermochemical hydrogen production cycle for reaching the DOE cost goals. Two approaches were considered for the hydrogen production step of the SA cycle: (1) photocatalytic, and (2) electrolytic oxidation of ammonium sulfite to ammonium sulfate in aqueous solutions. Also, two sub-cycles were evaluated for the oxygen evolution side of the SA cycle: (1) zinc sulfate/zinc oxide, and (2) potassium sulfate/potassium pyrosulfate. The laboratory testing and optimization of all the process steps for each version of the SA cycle were proven in the laboratory or have been fully demonstrated by others, but further optimization is still possible and needed. The solar configuration evolved to a 50 MW(thermal) central receiver system with a North heliostat field, a cavity receiver, and NaCl molten salt storage to allow continuous operation. The H2A economic model was used to optimize and trade-off SA cycle configurations. Parametric studies of chemical plant performance have indicated process efficiencies of ~20%. Although the current process efficiency is technically acceptable, an increased efficiency is needed if the DOE cost targets are to be reached. There are two interrelated areas in which there is the potential for significant efficiency improvements: electrolysis cell voltage and excessive water vaporization. Methods to significantly reduce water evaporation are

  7. Quantum-splitting oxide-based phosphors, method of producing, and rules for designing the same

    DOE Patents [OSTI]

    Setlur, Anant Achyut; Comanzo, Holly Ann; Srivastava, Alok Mani

    2003-09-16

    Strontium and strontium calcium aluminates and lanthanum and lanthanum magnesium borates activated with Pr.sup.3+ and Mn.sup.2+ exhibit characteristics of quantum-splitting phosphors. Improved quantum efficiency may be obtained by further doping with Gd.sup.3+. Refined rules for designing quantum-splitting phosphors include the requirement of incorporation of Gd.sup.3+ and Mn.sup.2+ in the host lattice for facilitation of energy migration.

  8. Spin polarized current from multiply-coupled rings with Zeeman-split quantum dots

    SciTech Connect (OSTI)

    Hedin, Eric R.; Joe, Yong S.

    2014-03-21

    We investigate transmission resonances and conductance properties of multiple, serially connected, direct-contact nanoscale rings using the tight-binding model. Quantum dots (QDs) are embedded in the two arms of each ring, and Zeeman-splitting of the QD energy levels is incorporated into the system Hamiltonian. Transmission bands develop as the number of rings in series increases, with a band-gap which is sensitive to the degree of Zeeman splitting and the initial settings of the QD site energy values. The current vs. voltage characteristics of the system can be modulated between Ohmic and semiconducting as a function of the Zeeman splitting. In addition, spin-polarized current results for selected ranges of the Fermi energy.

  9. The splitted laser beam filamentation in interaction of laser and an exponential decay inhomogeneous underdense plasma

    SciTech Connect (OSTI)

    Xia Xiongping; Yi Lin; Xu Bin; Lu Jianduo

    2011-10-15

    The splitted beam filamentation in interaction of laser and an exponential decay inhomogeneous underdense plasma is investigated. Based on Wentzel-Kramers-Brillouin (WKB) approximation and paraxial/nonparaxial ray theory, simulation results show that the steady beam width and single beam filamentation along the propagation distance in paraxial case is due to the influence of ponderomotive nonlinearity. In nonparaxial case, the influence of the off-axial of {alpha}{sub 00} and {alpha}{sub 02} (the departure of the beam from the Gaussian nature) and S{sub 02} (the departure from the spherical nature) results in more complicated ponderomotive nonlinearity and changing of the channel density and refractive index, which led to the formation of two/three splitted beam filamentation and the self-distortion of beam width. In addition, influence of several parameters on two/three splitted beam filamentation is discussed.

  10. Ions confined in spherical dielectric cavities modeled by a splitting field-theory

    SciTech Connect (OSTI)

    Lue, Leo; Linse, Per

    2015-04-14

    The properties of ions confined within spherical dielectric cavities are examined by a splitting field-theory and Monte Carlo simulations. Three types of cavities are considered: one possessing a uniform surface charge density, one with a uniform volume charge density, and one containing mobile ions. In all cases, mobile counterions are present within the dielectric sphere. The splitting theory is based on dividing the electrostatic interaction into long- and short-wavelength contributions and applying different approximations on the two contributions. The splitting theory works well for the case where the dielectric constant of the confining sphere is equal to or less than that of the medium external to the sphere. Nevertheless, by extending the theory with a virial expansion, the predictions are improved. However, when the dielectric constant of the confining sphere is greater than that of the medium outside the sphere, the splitting theory performs poorly, only qualitatively agreeing with the simulation data. In this case, the strong-coupling expansion does not seem to work well, and a modified mean-field theory where the counterions interact directly with only their own image charge gives improved predictions. The splitting theory works best for the system with a uniform surface charge density and worst for the system with a uniform volume charge density. Increasing the number of ions within the sphere, at a fixed radius, tends to increase the ion density near the surface of the sphere and leads to a depletion region in the sphere interior; however, varying the ion number does not lead to any qualitative changes in the performance of the splitting theory.

  11. Quantum-splitting oxide-based phosphors and method of producing the same

    DOE Patents [OSTI]

    Setlur, Anant Achyut; Srivastava, Alok Mani

    2003-09-02

    Strontium, calcium, strontium calcium, strontium calcium magnesium, calcium magnesium aluminates, and strontium borates activated with Pr.sup.3+ exhibit characteristics of quantum-splitting phosphors under VUV excitation. A large emission peak at about 405 nm under VUV excitation is used conveniently to identify quantum-splitting phosphors. Improvements may be achieved with addition of fluorides or boric acid as a flux during the preparation of the phosphors. It is also possible to predict improvement in quantum efficiency by observing the ratio of emission intensities at about 480 nm and about 610 nm.

  12. THERMODYNAMIC CONSIDERATIONS FOR THERMAL WATER SPLITTING PROCESSES AND HIGH TEMPERATURE ELECTROLYSIS

    SciTech Connect (OSTI)

    J. E. O'Brien

    2008-11-01

    A general thermodynamic analysis of hydrogen production based on thermal water splitting processes is presented. Results of the analysis show that the overall efficiency of any thermal water splitting process operating between two temperature limits is proportional to the Carnot efficiency. Implications of thermodynamic efficiency limits and the impacts of loss mechanisms and operating conditions are discussed as they pertain specifically to hydrogen production based on high-temperature electrolysis. Overall system performance predictions are also presented for high-temperature electrolysis plants powered by three different advanced nuclear reactor types, over their respective operating temperature ranges.

  13. Defect-engineered GaN:Mg nanowire arrays for overall water splitting under violet light

    SciTech Connect (OSTI)

    Kibria, M. G.; Chowdhury, F. A.; Zhao, S.; Mi, Z.; Trudeau, M. L.; Guo, H.

    2015-03-16

    We report that by engineering the intra-gap defect related energy states in GaN nanowire arrays using Mg dopants, efficient and stable overall neutral water splitting can be achieved under violet light. Overall neutral water splitting on Rh/Cr{sub 2}O{sub 3} co-catalyst decorated Mg doped GaN nanowires is demonstrated with intra-gap excitation up to 450?nm. Through optimized Mg doping, the absorbed photon conversion efficiency of GaN nanowires reaches ?43% at 375450?nm, providing a viable approach to extend the solar absorption of oxide and non-oxide photocatalysts.

  14. Influence of dense quantum plasmas on fine-structure splitting of Lyman doublets of hydrogenic systems

    SciTech Connect (OSTI)

    De, Madhab Ray, Debasis

    2015-05-15

    Relativistic calculations are performed to study the effects of oscillatory quantum plasma screening on the fine-structure splitting between the components of Lyman-? and ? line doublets of atomic hydrogen and hydrgen-like argon ion within dense quantum plasmas, where the effective two-body (electronnucleus) interaction is modeled by the ShuklaEliasson oscillatory exponential cosine screened-Coulomb potential. The numerical solutions of the radial Dirac equation for the quantum plasma-embedded atomic systems reveal that the oscillatory quantum screening effect suppresses the doublet (energy) splitting substantially and the suppression becomes more prominent at large quantum wave number k{sub q}. In the absence of the oscillatory cosine screening term, much larger amount of suppression is noticed at larger values of k{sub q}, and the corresponding results represent the screening effect of an exponential screened-Coulomb two-body interaction. The Z{sup 4} scaling of the Lyman doublet splitting in low-Z hydrogen isoelectronic series of ions in free space is violated in dense quantum plasma environments. The relativistic data for the doublet splitting in the zero screening (k{sub q}?=?0) case are in very good agreement with the NIST reference data, with slight discrepancies (?0.2%) arising from the neglect of the quantum electrodynamic effects.

  15. High Efficiency Spectrum Splitting Prototype Submodule Using Commercial CPV Cells (Presentation)

    SciTech Connect (OSTI)

    Keevers, M.; Lau, J.; Green, M.; Thomas, I.; Lasich, J.; King, R.; Emery, K.

    2014-11-01

    This presentation summarizes progress on the design, fabrication and testing of a proof-of-concept, prototype spectrum splitting CPV submodule using commercial CPV cells, aimed at demonstrating an independently confirmed efficiency above 40% at STC (1000 W/m2, AM1.5D ASTM G173-03, 25 degrees C).

  16. DOE NSF Partnership to Address Critical Challenges in Hydrogen Production from Solar Water Splitting

    Broader source: Energy.gov [DOE]

    EERE and the National Science Foundation (NSF) announce a funding opportunity in the area of renewable hydrogen technology research and development, specifically addressing discovery and development of advanced materials systems and chemical proceesses for direct photochemical and/or thermochemical water splitting for application in the solar production of hydrogen fuel.

  17. Tuning magnetic splitting of zigzag graphene nanoribbons by edge functionalization with hydroxyl groups

    SciTech Connect (OSTI)

    Zhang, Huizhen; Yang, Haifang; Li, Lin; Fu, Huixia; Ma, Wei; Niu, Chunyao; Sun, Jiatao; Meng, Sheng; Gu, Changzhi

    2015-03-21

    The electronic properties and relative stability of zigzag graphene nanoribbons are studied by varying the percentage of hydroxyl radicals for edge saturation using first principle calculations. The passivated structures of zigzag graphene nanoribbon have spin-polarized ground state with antiferromagnetic exchange coupling across the edge and ferromagnetic coupling along the edges. When the edges are specially passivated by hydroxyl, the potentials of spin exchange interaction across the two edges shift accordingly, resulting into a spin-semiconductor. Varying the concentration of hydroxyl groups can alter the maximum magnetization splitting. When the percentage of asymmetrically adsorbed hydroxyl reaches 50%, the magnetization splitting can reach a value as high as 275 meV due to the asymmetrical potential across the nanoribbon edges. These results would favor spintronic device applications based on zigzag graphene nanoribbons.

  18. Mechanism of cathode spot splitting in vacuum arcs in an oblique magnetic field

    SciTech Connect (OSTI)

    Beilis, I. I.

    2015-10-15

    Experiments in the last decade showed that for cathode spots in a magnetic field that obliquely intercepts the cathode surface, the current per spot increased with the transverse component of the magnetic field and decreased with the normal component. The present work analyzes the nature of cathode spot splitting in an oblique magnetic field. A physical model for cathode spot current splitting was developed, which considered the relation between the plasma kinetic pressure, self-magnetic pressure, and applied magnetic pressure in a current carrying cathode plasma jet. The current per spot was calculated, and it was found to increase with the tangential component of the magnetic field and to decrease with the normal component, which agrees well with the experimental dependence.

  19. A split-electrode for clearing scattered electrons in the RHIC e-lens

    SciTech Connect (OSTI)

    Gu X.; Pikin, A.; Thieberger, P.; Fischer, W.; Hock, J.; Hamdi, K.; Gassner,D.; Luo, Y.; Montag, C.; Okamura, M.

    2012-05-20

    We are designing two electron lenses that will be installed at RHIC IR10 to compensate for the head-on beam-beam effect. To clear accumulated scattered electrons from 100 GeV proton-electron head-on collisions in the e-lens, a clearing split electrode may be constructed. The feasibility of this proposed electrode was demonstrated via the CST Particle Studio and Opera program simulations. By splitting one of the drift tubes in the e-lens and applying {approx} 380 V across the two parts, the scattered electrons can be cleared out within several hundred micro-seconds. At the same time we can restrict the unwanted shift of the primary electron-beam that already passed the 2-m interaction region in e-lens, to less than 15um.

  20. Method and split cavity oscillator/modulator to generate pulsed particle beams and electromagnetic fields

    DOE Patents [OSTI]

    Clark, M.C.; Coleman, P.D.; Marder, B.M.

    1993-08-10

    A compact device called the split cavity modulator whose self-generated oscillating electromagnetic field converts a steady particle beam into a modulated particle beam. The particle beam experiences both signs of the oscillating electric field during the transit through the split cavity modulator. The modulated particle beam can then be used to generate microwaves at that frequency and through the use of extractors, high efficiency extraction of microwave power is enabled. The modulated beam and the microwave frequency can be varied by the placement of resistive wires at nodes of oscillation within the cavity. The short beam travel length through the cavity permit higher currents because both space charge and pinching limitations are reduced. The need for an applied magnetic field to control the beam has been eliminated.

  1. Method and split cavity oscillator/modulator to generate pulsed particle beams and electromagnetic fields

    DOE Patents [OSTI]

    Clark, M. Collins; Coleman, P. Dale; Marder, Barry M.

    1993-01-01

    A compact device called the split cavity modulator whose self-generated oscillating electromagnetic field converts a steady particle beam into a modulated particle beam. The particle beam experiences both signs of the oscillating electric field during the transit through the split cavity modulator. The modulated particle beam can then be used to generate microwaves at that frequency and through the use of extractors, high efficiency extraction of microwave power is enabled. The modulated beam and the microwave frequency can be varied by the placement of resistive wires at nodes of oscillation within the cavity. The short beam travel length through the cavity permit higher currents because both space charge and pinching limitations are reduced. The need for an applied magnetic field to control the beam has been eliminated.

  2. Realization of tunable spin-dependent splitting in intrinsic photonic spin Hall effect

    SciTech Connect (OSTI)

    Ling, Xiaohui; Yi, Xunong; Zhou, Xinxing; Liu, Yachao; Shu, Weixing; Wen, Shuangchun; Luo, Hailu

    2014-10-13

    We report the realization of tunable spin-dependent splitting in intrinsic photonic spin Hall effect. By breaking the rotational symmetry of a cylindrical vector beam, the intrinsic vortex phases that the two spin components of the vector beam carries, which is similar to the geometric Pancharatnam-Berry phase, are no longer continuous in the azimuthal direction, and leads to observation of spin accumulation at the opposite edge of the beam. Due to the inherent nature of the phase and independency of light-matter interaction, the observed photonic spin Hall effect is intrinsic. Modulating the topological charge of the vector beam, the spin-dependent splitting can be enhanced and the direction of spin accumulation is switchable. Our findings may provide a possible route for generation and manipulation of spin-polarized photons, and enables spin-based photonics applications.

  3. Millimeter wave detection via Autler-Townes splitting in rubidium Rydberg atoms

    SciTech Connect (OSTI)

    Gordon, Joshua A. Holloway, Christopher L.; Schwarzkopf, Andrew; Anderson, Dave A.; Miller, Stephanie; Thaicharoen, Nithiwadee; Raithel, Georg

    2014-07-14

    In this paper, we demonstrate the detection of millimeter waves via Autler-Townes splitting in {sup 85}Rb Rydberg atoms. This method may provide an independent, atom-based, SI-traceable method for measuring mm-wave electric fields, which addresses a gap in current calibration techniques in the mm-wave regime. The electric-field amplitude within a rubidium vapor cell in the WR-10 wave guide band is measured for frequencies of 93.71 GHz and 104.77?GHz. Relevant aspects of Autler-Townes splitting originating from a four-level electromagnetically induced transparency scheme are discussed. We measured the E-field generated by an open-ended waveguide using this technique. Experimental results are compared to a full-wave finite element simulation.

  4. Two for the Price of One: Water and Carbon Dioxide Splitting via a Single

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

    Catalyst | U.S. DOE Office of Science (SC) 2 » Two for the Price of One: Water and Carbon Dioxide Splitting via a Single Catalyst Basic Energy Sciences (BES) BES Home About Research Facilities Science Highlights Benefits of BES Funding Opportunities Basic Energy Sciences Advisory Committee (BESAC) Community Resources Contact Information Basic Energy Sciences U.S. Department of Energy SC-22/Germantown Building 1000 Independence Ave., SW Washington, DC 20585 P: (301) 903-3081 F: (301)

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

    SciTech Connect (OSTI)

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

    2012-03-01

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

  6. Spin orbit splitting of the photon induced Fano resonance in an oscillating graphene electrostatic barrier

    SciTech Connect (OSTI)

    Biswas, R.; Sinha, C.

    2014-04-07

    We investigate theoretically the effect of a time dependent oscillating potential on the transport property of the Dirac Fermion through a monolayer graphene electrostatic barrier under the influence of the Rashba spin orbit interaction. The time dependent problem is solved in the frame work of the non-perturbative Floquet approach. It is noted that the dynamic condition of the barrier may be controlled by tuning the Rashba parameter. Introduction of the spin orbit interaction causes splitting of the Fano resonance (FR), a characteristic feature in photon assisted tunneling. The separation between the spin split FR's gives an indirect measure of the fine structure of the quasi-hole bound state inside the barrier. The present findings on the Rashba splitting of the FR and its external control by tuning the oscillating field parameters might have potential for applications in spintronic devices, especially in the spin field effect transistors. The spin polarization of different Floquet sidebands is found to be quite sensitive to the spin-pseudospin interaction.

  7. Semiconductor-based photoelectrochemical water splitting at the limit of very wide depletion region

    SciTech Connect (OSTI)

    Liu, Mingzhao; Lyons, John L.; Yan, Danhua H.; Hybertsen, Mark S.

    2015-11-23

    In semiconductor-based photoelectrochemical (PEC) water splitting, carrier separation and delivery largely relies on the depletion region formed at the semiconductor/water interface. As a Schottky junction device, the trade-off between photon collection and minority carrier delivery remains a persistent obstacle for maximizing the performance of a water splitting photoelectrode. Here, it is demonstrated that the PEC water splitting efficiency for an n-SrTiO3 (n-STO) photoanode is improved very significantly despite its weak indirect band gap optical absorption (α < 10⁴ cm⁻¹), by widening the depletion region through engineering its doping density and profile. Graded doped n-SrTiO3 photoanodes are fabricated with their bulk heavily doped with oxygen vacancies but their surface lightly doped over a tunable depth of a few hundred nanometers, through a simple low temperature re-oxidation technique. The graded doping profile widens the depletion region to over 500 nm, thus leading to very efficient charge carrier separation and high quantum efficiency (>70%) for the weak indirect transition. As a result, this simultaneous optimization of the light absorption, minority carrier (hole) delivery, and majority carrier (electron) transport by means of a graded doping architecture may be useful for other indirect band gap photocatalysts that suffer from a similar problem of weak optical absorption.

  8. Semiconductor-based photoelectrochemical water splitting at the limit of very wide depletion region

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

    Liu, Mingzhao; Lyons, John L.; Yan, Danhua H.; Hybertsen, Mark S.

    2015-11-23

    In semiconductor-based photoelectrochemical (PEC) water splitting, carrier separation and delivery largely relies on the depletion region formed at the semiconductor/water interface. As a Schottky junction device, the trade-off between photon collection and minority carrier delivery remains a persistent obstacle for maximizing the performance of a water splitting photoelectrode. Here, it is demonstrated that the PEC water splitting efficiency for an n-SrTiO3 (n-STO) photoanode is improved very significantly despite its weak indirect band gap optical absorption (α < 10⁴ cm⁻¹), by widening the depletion region through engineering its doping density and profile. Graded doped n-SrTiO3 photoanodes are fabricated with their bulkmore » heavily doped with oxygen vacancies but their surface lightly doped over a tunable depth of a few hundred nanometers, through a simple low temperature re-oxidation technique. The graded doping profile widens the depletion region to over 500 nm, thus leading to very efficient charge carrier separation and high quantum efficiency (>70%) for the weak indirect transition. As a result, this simultaneous optimization of the light absorption, minority carrier (hole) delivery, and majority carrier (electron) transport by means of a graded doping architecture may be useful for other indirect band gap photocatalysts that suffer from a similar problem of weak optical absorption.« less

  9. Vibrational dynamics of zero-field-splitting hamiltonian in gadolinium-based MRI contrast agents from ab initio molecular dynamics

    SciTech Connect (OSTI)

    Lasoroski, Aurélie; Vuilleumier, Rodolphe; Pollet, Rodolphe

    2014-07-07

    The electronic relaxation of gadolinium complexes used as MRI contrast agents was studied theoretically by following the short time evolution of zero-field-splitting parameters. The statistical analysis of ab initio molecular dynamics trajectories provided a clear separation between static and transient contributions to the zero-field-splitting. For the latter, the correlation time was estimated at approximately 0.1 ps. The influence of the ligand was also probed by replacing one pendant arm of our reference macrocyclic complex by a bulkier phosphonate arm. In contrast to the transient contribution, the static zero-field-splitting was significantly influenced by this substitution.

  10. Characterizing Fractures in Geysers Geothermal Field by Micro-seismic Data, Using Soft Computing, Fractals, and Shear Wave Anisotropy

    SciTech Connect (OSTI)

    Aminzadeh, Fred; Sammis, Charles; Sahimi, Mohammad; Okaya, David

    2015-04-30

    The ultimate objective of the project was to develop new methodologies to characterize the northwestern part of The Geysers geothermal reservoir (Sonoma County, California). The goal is to gain a better knowledge of the reservoir porosity, permeability, fracture size, fracture spacing, reservoir discontinuities (leaky barriers) and impermeable boundaries.

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

    DOE Patents [OSTI]

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

    1998-02-17

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

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

    DOE Patents [OSTI]

    Hall, Maclin S.; Jackson, Theodore G.; Knerr, Christopher

    1998-02-17

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

  13. Splitting of magnetic dipole modes in anisotropic TiO 2 micro-spheres: Splitting of magnetic dipole modes in anisotropic TiO 2 micro-spheres

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

    Khromova, Irina; Kužel, Petr; Brener, Igal; Reno, John L.; Chung Seu, U-Chan; Elissalde, Catherine; Maglione, Mario; Mounaix, Patrick; Mitrofanov, Oleg

    2016-06-27

    Monocrystalline titanium dioxide (TiO2) micro-spheres support two orthogonal magnetic dipole modes at terahertz (THz) frequencies due to strong dielectric anisotropy. For the first time, we experimentally detected the splitting of the first Mie mode in spheres of radii inline imagem through near-field time-domain THz spectroscopy. By fitting the Fano lineshape model to the experimentally obtained spectra of the electric field detected by the sub-wavelength aperture probe, we found that the magnetic dipole resonances in TiO2 spheres have narrow linewidths of only tens of gigahertz. Lastly, anisotropic TiO2 micro-resonators can be used to enhance the interplay of magnetic and electric dipolemore » resonances in the emerging THz all-dielectric metamaterial technology.« less

  14. Micro-Earthquake At Chena Geothermal Area (Holdmann, Et Al.,...

    Open Energy Info (EERE)

    Activity Date 2006 - 2007 Usefulness not indicated DOE-funding Unknown Exploration Basis Microseismic- Exploration program undertaken by the DOE-funded Geothermal Resource...

  15. Micro-Earthquake At Coso Geothermal Area (2011) | Open Energy...

    Open Energy Info (EERE)

    DOE-funding Unknown Exploration Basis To analyze temporal velocity variations Notes Microseismic data recorded between 1996 and 2008 was used to determine the temporally...

  16. Micro-Earthquake At Under Steamboat Springs Area (Warpinski,...

    Open Energy Info (EERE)

    running orthogonal to each other which are presumably related to the fault system. The microseismic survey resulted in the detection of a number of shallow microseisms that...

  17. Heat flow and microearthquake studies, Coso Geothermal Area,...

    Open Energy Info (EERE)

    The sites for ten heat flow boreholes were located primarily using the available seismic ground noise and electrical resistivity data. Difficulty was encountered in the drilling...

  18. Micro-Earthquake At Neal Hot Springs Geothermal Area (Nichols...

    Open Energy Info (EERE)

    seismic sensor, a data acquisition system that records information onto flash drives, a solar panel and battery, and a fence to keep cows out. References Scott Nichols, David...

  19. Anomalous distribution of microearthquakes in the Newberry Geothermal...

    Office of Scientific and Technical Information (OSTI)

    Additional Journal Information: Journal Volume: 63; Journal Issue: C; Related Information: CHORUS Timestamp: 2016-06-26 20:29:56; Journal ID: ISSN 0375-6505 Publisher: Elsevier ...

  20. Micro-Earthquake At Roosevelt Hot Springs Geothermal Area (Ward...

    Open Energy Info (EERE)

    Area. References S. H. Ward, W. T. Parry, W. P. Nash, W. R. Sill, K. L. Cook, R. B. Smith, D. S. Chapman, F. H. Brown, J. A. Whelan, J. R. Bowman (1978) A Summary of the...

  1. Micro-Earthquake At Kilauea East Rift Geothermal Area (Gardner...

    Open Energy Info (EERE)

    of faults as well as produce an accurate velocity model of the region. References Murray C. Gardner, James R. McNitt, Christopher W. Klein, James B. Koenig, Dean Nakano (1995)...

  2. Micro-Earthquake At Coso Geothermal Area (1996) | Open Energy...

    Open Energy Info (EERE)

    at 0.5 to 1.2 km in depth below Devil's Kitchen, Nicol Prospects, and Coso Hot Springs. A vertical, low Q ( 36 in contrast with surrounding rock of 80) region is interpreted as...

  3. Micro-Earthquake At Kilauea East Rift Geothermal Area (FURUMOTO...

    Open Energy Info (EERE)

    potential as part of the coordinated exploration program for geothermal sources on the Big Island of Hawaii. Notes A two week micro-seismic study in the Puna district was...

  4. Micro-Earthquake At Raft River Geothermal Area (1982) | Open...

    Open Energy Info (EERE)

    Zandt, G.; Mcpherson, L.; Schaff, S.; Olsen, S. (1 May 1982) Seismic baseline and induction studies- Roosevelt Hot Springs, Utah and Raft River, Idaho Additional References...

  5. Micro-Earthquake At Roosevelt Hot Springs Geothermal Area (Zandt...

    Open Energy Info (EERE)

    Zandt, G.; Mcpherson, L.; Schaff, S.; Olsen, S. (1 May 1982) Seismic baseline and induction studies- Roosevelt Hot Springs, Utah and Raft River, Idaho Additional References...

  6. Microearthquake moment tensors from the Coso Geothermal area...

    Open Energy Info (EERE)

    which propagated to the NNE and upward. Co-injection focal mechanisms reveal combined crack-opening and shear motion. Stress release and mode of failure differed between the...

  7. Micro-Earthquake At Waunita Hot Springs Geothermal Area (Lange...

    Open Energy Info (EERE)

    assess the extent of active fault failure and the potential importance of fracture permeability in the subsurface surrounding the hot springs. Notes The first documented...

  8. Non-Double-Couple Microearthquakes At Long Valley Caldera, California...

    Open Energy Info (EERE)

    shear and extensional faulting with a volume-compensating process, such as rapid flow of water, steam, or CO2 into opening tensile cracks. Source orientations of earthquakes in...

  9. Micro-Earthquake At Long Valley Caldera Geothermal Area (Foulger...

    Open Energy Info (EERE)

    shear and extensional faulting with a volume-compensating process, such as rapid flow of water, steam, or CO2 into opening tensile cracks. Source orientations of earthquakes in...

  10. Micro-Earthquake At Coso Geothermal Area (2000) | Open Energy...

    Open Energy Info (EERE)

    5 km. It was calculate that there are 375 good quality mini-array beamed receiver functions for teleseismic events. References Gilbert, H.J.; Wilson, C.K. ; Jones, C.H.;...

  11. Micro-Earthquake At New York Canyon Geothermal Area (2011) |...

    Open Energy Info (EERE)

    Rock, D.; Peterson, J.; Jarpe, S. (1 January 2011) DOE REAL-TIME SEISMIC MONITORING AT ENHANCED GEOTHERMAL SYSTEM SITES Additional References Retrieved from "http:...

  12. Micro-Earthquake At Desert Peak Geothermal Area (2011) | Open...

    Open Energy Info (EERE)

    Rock, D.; Peterson, J.; Jarpe, S. (1 January 2011) DOE REAL-TIME SEISMIC MONITORING AT ENHANCED GEOTHERMAL SYSTEM SITES Additional References Retrieved from "http:...

  13. Micro-Earthquake At Newberry Caldera Geothermal Area (2011) ...

    Open Energy Info (EERE)

    Rock, D.; Peterson, J.; Jarpe, S. (1 January 2011) DOE REAL-TIME SEISMIC MONITORING AT ENHANCED GEOTHERMAL SYSTEM SITES Additional References Retrieved from "http:...

  14. Micro-Earthquake At Geysers Geothermal Area (2011) | Open Energy...

    Open Energy Info (EERE)

    Rock, D.; Peterson, J.; Jarpe, S. (1 January 2011) DOE REAL-TIME SEISMIC MONITORING AT ENHANCED GEOTHERMAL SYSTEM SITES Additional References Retrieved from "http:...

  15. Micro-Earthquake At Coso Geothermal Area (1974) | Open Energy...

    Open Energy Info (EERE)

    as many as 100 or more distinct local events; more than two thousand events with S-P times of less than three seconds were detected; observed low value for Poisson's ratio which...

  16. Micro-Earthquake At Coso Geothermal Area (1987) | Open Energy...

    Open Energy Info (EERE)

    variations in the Coso region, California, derived from local earthquake travel times Additional References Retrieved from "http:en.openei.orgwindex.php?titleMicro-Ear...

  17. Multiple Ruptures For Long Valley Microearthquakes- A Link To...

    Open Energy Info (EERE)

    located and analyzed as a function of azimuth, offset, and source characteristics. Eight prime examples lie within two, 7 km-deep clusters of seismicity separated by about 1 km,...

  18. Micro-Earthquake At Roosevelt Hot Springs Geothermal Area (Faulder...

    Open Energy Info (EERE)

    Unknown Exploration Basis Faulder 1991 Conceptual Geological Model compilation and literature review of the Roosevelt Hot Springs Geothermal Area. Notes P-wave passive seismic...

  19. Micro-Earthquake At Kilauea East Rift Geothermal Area (Kenedi...

    Open Energy Info (EERE)

    identify fault and fracture orientations, and locate zones of high and low velocities. Based on earthquake sizes, locations, and depths the evidence from this study suggests...

  20. Micro-Earthquake At North Brawley Geothermal Area (Hauksson,...

    Open Energy Info (EERE)

    data is available to be used for a more localized studies. References E. Hauksson, W. Yang, P. M. Shearer (2012) Waveform Relocated Earthquake Catalog for Southern California...

  1. Micro-Earthquake (Majer, 2003) | Open Energy Information

    Open Energy Info (EERE)

    DOE-funding Unknown Notes The goal of this work is to evaluate the most promising methods and approaches that may be used for improved geothermal exploration and reservoir...

  2. Impacts of urban transportation mode split on CO{sub 2} emissions in Jinan, China.

    SciTech Connect (OSTI)

    He, D.; Meng, F.; Wang, M.; He, K.

    2011-04-01

    As the world's largest developing country, China currently is undergoing rapid urbanization and motorization, which will result in far-reaching impacts on energy and the environment. According to estimates, energy use and carbon emissions in the transportation sector will comprise roughly 30% of total emissions by 2030. Since the late 1990s, transportation-related issues such as energy, consumption, and carbon emissions have become a policy focus in China. To date, most research and policies have centered on vehicle technologies that promote vehicle efficiency and reduced emissions. Limited research exists on the control of greenhouse gases through mode shifts in urban transportation - in particular, through the promotion of public transit. The purpose of this study is to establish a methodology to analyze carbon emissions from the urban transportation sector at the Chinese city level. By using Jinan, the capital of China's Shandong Province, as an example, we have developed an analytical model to simulate energy consumption and carbon emissions based on the number of trips, the transportation mode split, and the trip distance. This model has enabled us to assess the impacts of the transportation mode split on energy consumption and carbon emissions. Furthermore, this paper reviews a set of methods for data collection, estimation, and processing for situations where statistical data are scarce in China. This paper also describes the simulation of three transportation system development scenarios. The results of this study illustrate that if no policy intervention is implemented for the transportation mode split (the business-as-usual (BAU) case), then emissions from Chinese urban transportation systems will quadruple by 2030. However, a dense, mixed land-use pattern, as well as transportation policies that encourage public transportation, would result in the elimination of 1.93 million tons of carbon emissions - approximately 50% of the BAU scenario emissions.

  3. Light-splitting photovoltaic system utilizing two dual-junction solar cells

    SciTech Connect (OSTI)

    Xiong, Kanglin; Yang, Hui; Lu, Shulong; Dong, Jianrong; Zhou, Taofei; Wang, Rongxin; Jiang, Desheng

    2010-12-15

    There are many difficulties limiting the further development of monolithic multi-junction solar cells, such as the growth of lattice-mismatched material and the current matching constraint. As an alternative approach, the light-splitting photovoltaic system is investigated intensively in different aspects, including the energy loss mechanism and the choice of energy bandgaps of solar cells. Based on the investigation, a two-dual junction system has been implemented employing lattice-matched GaInP/GaAs and InGaAsP/InGaAs cells grown epitaxially on GaAs and InP substrates, respectively. (author)

  4. Traveling wave device for combining or splitting symmetric and asymmetric waves

    DOE Patents [OSTI]

    Möbius, Arnold; Ives, Robert Lawrence

    2005-07-19

    A traveling wave device for the combining or splitting of symmetric and asymmetric traveling wave energy includes a feed waveguide for traveling wave energy, the feed waveguide having an input port and a launching port, a reflector for coupling wave energy between the feed waveguide and a final waveguide for the collection and transport of wave energy to or from the reflector. The power combiner has a launching port for symmetrical waves which includes a cylindrical section coaxial to the feed waveguide, and a launching port for asymmetric waves which includes a sawtooth rotated about a central axis.

  5. Work Together or Go It Alone? Microbes Are Split on the Answer | U.S. DOE

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

    Work Plans & Manuals Work Plans & Manuals This list contains audit and inspections manuals and a list of planned reviews to be conducted by the Office of Audits and Inspections. Documents Available for Download November 20, 2014 Work Plan FY 2016 Planned Audits and Inspections for FY 2016 December 23, 2014 Audit Manual 2014 Office of Inspector General Audit Manual Office of Science (SC)

    Work Together or Go It Alone? Microbes Are Split on the Answer Biological and Environmental

  6. NREL Documents Efficiency of Mini-Split Heat Pumps (Fact Sheet)

    SciTech Connect (OSTI)

    Not Available

    2012-06-01

    A new report delivers mini-split heat pump (MSHP) performance data for use in whole-building simulation tools. Mini-split heat pumps (MSHPs) are highly efficient refrigerant-based air conditioning and heating systems that permit room-by-room conditioning and control in homes. Because of their size, efficiency, and price, MSHPs are very popular overseas and are gaining market share in energy-efficient home upgrades in the United States. They are a good option for retrofitting older homes that lack ductwork. To evaluate MSHP cost effectiveness and performance in U.S. homes, National Renewable Energy Laboratory (NREL) researchers are studying these systems in the laboratory, simulated buildings, and field test settings. A new NREL report describes an innovative laboratory approach to testing MSHPs and includes experimental performance maps for use in whole-building simulation tools. Most public information on MSHP performance is provided by equipment manufacturers, and is typically limited to performance at a single operating speed for heating and cooling. Mini-split heat pumps use variable speed components that spin up and down to continuously meet the heating or cooling need, significantly improving a system's operating efficiency. Measuring that efficiency in a laboratory is challenging and required new approaches to performance testing. NREL researchers worked with colleagues at Purdue University's Herrick Labs and Ecotope, Inc. to refine and apply this new approach to a suite of MSHP products. Researchers measured the performance of two MSHPs across a variety of operating conditions, which allowed, for the first time, development of accurate building simulation MSHP models. In the laboratory tests, researchers found that both MSHPs achieved manufacturer-reported performance at rating conditions. However, at other temperature and humidity conditions, the heat pumps capacity ranged from 40% above to 54% below the manufacturer-reported values. Knowing how

  7. Sunlight-Driven Hydrogen Formation by Membrane-Supported Photoelectrochemical Water Splitting

    SciTech Connect (OSTI)

    Lewis, Nathan S.

    2014-03-26

    This report describes the significant advances in the development of the polymer-supported photoelectrochemical water-splitting system that was proposed under DOE grant number DE-FG02-05ER15754. We developed Si microwire-array photoelectrodes, demonstrated control over the material and light-absorption properties of the microwire-array photoelectrodes, developed inexpensive processes for synthesizing the arrays, and doped the arrays p-type for use as photocathodes. We also developed techniques for depositing metal-nanoparticle catalysts of the hydrogen-evolution reaction (HER) on the wire arrays, investigated the stability and catalytic performance of the nanoparticles, and demonstrated that Ni-Mo alloys are promising earth-abundant catalysts of the HER. We also developed methods that allow reuse of the single-crystalline Si substrates used for microwire growth and methods of embedding the microwire photocathodes in plastic to enable large-scale processing and deployment of the technology. Furthermore we developed techniques for controlling the structure of WO3 films, and demonstrated that structural control can improve the quantum yield of photoanodes. Thus, by the conclusion of this project, we demonstrated significant advances in the development of all components of a sunlight-driven membrane-supported photoelectrochemical water-splitting system. This final report provides descriptions of some of the scientific accomplishments that were achieved under the support of this project and also provides references to the peer-reviewed publications that resulted from this effort.

  8. Baryon mass splittings and strong CP violation in SU(3) chiral perturbation theory

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

    de Vries, Jordy; Mereghetti, Emanuele; Walker-Loud, Andre P.

    2015-10-08

    We study SU(3) flavor breaking corrections to the relation between the octet baryon masses and the nucleon-meson CP-violating interactions induced by the QCD theta term. We also work within the framework of SU(3) chiral perturbation theory and work through next-to-next-to-leading order in the SU(3) chiral expansion, which is O(m2q). At lowest order, the CP-odd couplings induced by the QCD θ- term are determined by mass splittings of the baryon octet, the classic result of Crewther et al. We show that for each isospin-invariant CP-violating nucleon-meson interaction there exists one relation which is respected by loop corrections up to the ordermore » we work, while other leading-order relations are violated. With these relations we extract a precise value of the pion-nucleon coupling g-0 by using recent lattice QCD evaluations of the proton-neutron mass splitting. Additionally, we derive semi-precise values for CP-violating coupling constants between heavier mesons and nucleons and discuss their phenomenological impact on electric dipole moments of nucleons and nuclei.« less

  9. Magnetic thin-film split-domain current sensor-recorder

    DOE Patents [OSTI]

    Hsieh, Edmund J.

    1979-01-01

    A sensor-recorder for recording a representation of the direction and peak amplitude of a transient current. A magnetic thin film is coated on a glass substrate under the influence of a magnetic field so that the finished film is magnetically uniaxial and anisotropic. The film is split into two oppositely magnetized contiguous domains with a central boundary by subjecting adjacent portions of the film simultaneously to magnetic fields that are opposed 180.degree.. With the split-domain sensor-recorder placed with the film plane and domain boundary either perpendicular or parallel to the expected conductive path of a transient current, the occurrence of the transient causes switching of a portion of one domain to the direction of the other domain. The amount of the switched domain portion is indicative of the amplitude of the peak current of the transient, while the particular domain that is switched is indicative of the direction of the current. The resulting domain patterns may be read with a passive magnetic tape viewer.

  10. Synthesis and characterization of ferrite materials for thermochemical CO2 splitting using concentrated solar energy.

    SciTech Connect (OSTI)

    Stechel, Ellen Beth; Ambrosini, Andrea; Coker, Eric Nicholas; Rodriguez, Mark Andrew; Miller, James Edward; Evans, Lindsey R.; Livers, Stephanie

    2010-07-01

    The Sunshine to Petrol effort at Sandia aims to convert carbon dioxide and water to precursors for liquid hydrocarbon fuels using concentrated solar power. Significant advances have been made in the field of solar thermochemical CO{sub 2}-splitting technologies utilizing yttria-stabilized zirconia (YSZ)-supported ferrite composites. Conceptually, such materials work via the basic redox reactions: Fe{sub 3}O{sub 4} {yields} 3FeO + 0.5O{sub 2} (Thermal reduction, >1350 C) and 3FeO + CO{sub 2} {yields} Fe{sub 3}O{sub 4} + CO (CO{sub 2}-splitting oxidation, <1200 C). There has been limited fundamental characterization of the ferrite-based materials at the high temperatures and conditions present in these cycles. A systematic study of these composites is underway in an effort to begin to elucidate microstructure, structure-property relationships, and the role of the support on redox behavior under high-temperature reducing and oxidizing environments. In this paper the synthesis, structural characterization (including scanning electron microscopy and room temperature and in-situ x-ray diffraction), and thermogravimetric analysis of YSZ-supported ferrites will be reported.

  11. Synthesis and characterization of metal oxide materials for thermochemical CO2 splitting using concentrated solar energy.

    SciTech Connect (OSTI)

    Stechel, Ellen Beth; Ambrosini, Andrea; Coker, Eric Nicholas; Rodriguez, Mark Andrew; Miller, James Edward; Evans, Lindsey R.; Livers, Stephanie

    2010-07-01

    The Sunshine to Petrol effort at Sandia aims to convert carbon dioxide and water to precursors for liquid hydrocarbon fuels using concentrated solar power. Significant advances have been made in the field of solar thermochemical CO{sub 2}-splitting technologies utilizing yttria-stabilized zirconia (YSZ)-supported ferrite composites. Conceptually, such materials work via the basic redox reactions: Fe{sub 3}O{sub 4} {yields} 3FeO + 0.5O{sub 2} (Thermal reduction, >1350 C) and 3FeO + CO{sub 2} {yields} Fe{sub 3}O{sub 4} + CO (CO{sub 2}-splitting oxidation, <1200 C). There has been limited fundamental characterization of the ferrite-based materials at the high temperatures and conditions present in these cycles. A systematic study of these composites is underway in an effort to begin to elucidate microstructure, structure-property relationships, and the role of the support on redox behavior under high-temperature reducing and oxidizing environments. In this paper the synthesis, structural characterization (including scanning electron microscopy and room temperature and in-situ x-ray diffraction), and thermogravimetric analysis of YSZ-supported ferrites will be reported.

  12. Statistical assessment of fish behavior from split-beam hydro-acoustic sampling

    SciTech Connect (OSTI)

    McKinstry, Craig A.; Simmons, Mary Ann; Simmons, Carver S.; Johnson, Robert L.

    2005-04-01

    Statistical methods are presented for using echo-traces from split-beam hydro-acoustic sampling to assess fish behavior in response to a stimulus. The data presented are from a study designed to assess the response of free-ranging, lake-resident fish, primarily kokanee (Oncorhynchus nerka) and rainbow trout (Oncorhynchus mykiss) to high intensity strobe lights, and was conducted at Grand Coulee Dam on the Columbia River in Northern Washington State. The lights were deployed immediately upstream from the turbine intakes, in a region exposed to daily alternating periods of high and low flows. The study design included five down-looking split-beam transducers positioned in a line at incremental distances upstream from the strobe lights, and treatments applied in randomized pseudo-replicate blocks. Statistical methods included the use of odds-ratios from fitted loglinear models. Fish-track velocity vectors were modeled using circular probability distributions. Both analyses are depicted graphically. Study results suggest large increases of fish activity in the presence of the strobe lights, most notably at night and during periods of low flow. The lights also induced notable bimodality in the angular distributions of the fish track velocity vectors. Statistical summaries are presented along with interpretations on fish behavior.

  13. Porous SiC nanowire arrays as stable photocatalyst for water splitting under UV irradiation

    SciTech Connect (OSTI)

    Liu, Hailong; She, Guangwei; Mu, Lixuan; Shi, Wensheng

    2012-03-15

    Highlights: Black-Right-Pointing-Pointer Arrays of porous SiC nanowires prepared by a facile in situ carbonizing method. Black-Right-Pointing-Pointer Utilizing the SiC nanowire arrays as photocatalysis for water splitting. Black-Right-Pointing-Pointer Excellent photocatalytic performance under the UV irradiation. Black-Right-Pointing-Pointer Very high stability of the SiC nanowire photocatalyst. -- Abstract: In this study, we report the fabrication and photocatalytic properties of the oriented arrays of SiC nanowires on the Si substrate. The SiC nanowire arrays were prepared by carbonizing the Si nanowire arrays with the graphite powder at 1250 Degree-Sign C. The as-prepared SiC nanowires are highly porous, which endows them with a high surface-to-volume ratio. Considering the large surface areas and the high stability, the porous SiC nanowire arrays were used as photocatalyst for water splitting under UV irradiation. It was found that such porous SiC structure exhibited an enhanced and extremely stable photocatalytic performance.

  14. Charge transfer mechanism in titanium-doped microporous silica for photocatalytic water-splitting applications

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

    Sapp, Wendi; Koodali, Ranjit; Kilin, Dmitri

    2016-02-29

    Solar energy conversion into chemical form is possible using artificial means. One example of a highly-efficient fuel is solar energy used to split water into oxygen and hydrogen. Efficient photocatalytic water-splitting remains an open challenge for researchers across the globe. Despite significant progress, several aspects of the reaction, including the charge transfer mechanism, are not fully clear. Density functional theory combined with density matrix equations of motion were used to identify and characterize the charge transfer mechanism involved in the dissociation of water. A simulated porous silica substrate, using periodic boundary conditions, with Ti4+ ions embedded on the inner poremore » wall was found to contain electron and hole trap states that could facilitate a chemical reaction. A trap state was located within the silica substrate that lengthened relaxation time, which may favor a chemical reaction. A chemical reaction would have to occur within the window of photoexcitation; therefore, the existence of a trapping state may encourage a chemical reaction. Furthermore, this provides evidence that the silica substrate plays an integral part in the electron/hole dynamics of the system, leading to the conclusion that both components (photoactive materials and support) of heterogeneous catalytic systems are important in optimization of catalytic efficiency.« less

  15. Excitonic splitting and coherent electronic energy transfer in the gas-phase benzoic acid dimer

    SciTech Connect (OSTI)

    Ottiger, Philipp; Leutwyler, Samuel

    2012-11-28

    The benzoic acid dimer, (BZA){sub 2}, is a paradigmatic symmetric hydrogen bonded dimer with two strong antiparallel hydrogen bonds. The excitonic S{sub 1}/S{sub 2} state splitting and coherent electronic energy transfer within supersonically cooled (BZA){sub 2} and its {sup 13}C-, d{sub 1}-, d{sub 2}-, and {sup 13}C/d{sub 1}- isotopomers have been investigated by mass-resolved two-color resonant two-photon ionization spectroscopy. The (BZA){sub 2}-(h-h) and (BZA){sub 2}-(d-d) dimers are C{sub 2h} symmetric, hence only the S{sub 2} Leftwards-Arrow S{sub 0} transition can be observed, the S{sub 1} Leftwards-Arrow S{sub 0} transition being strictly electric-dipole forbidden. A single {sup 12}C/{sup 13}C or H/D isotopic substitution reduces the symmetry of the dimer to C{sub s}, so that the isotopic heterodimers (BZA){sub 2}-{sup 13}C, (BZA){sub 2}-(h-d), (BZA){sub 2}-(h{sup 13}C-d), and (BZA){sub 2}-(h-d{sup 13}C) show both S{sub 1} Leftwards-Arrow S{sub 0} and S{sub 2} Leftwards-Arrow S{sub 0} bands. The S{sub 1}/S{sub 2} exciton splitting inferred is {Delta}{sub exc}= 0.94 {+-} 0.1 cm{sup -1}. This is the smallest splitting observed so far for any H-bonded gas-phase dimer. Additional isotope-dependent contributions to the splittings, {Delta}{sub iso}, arise from the change of the zero-point vibrational energy upon electronic excitation and range from {Delta}{sub iso}= 3.3 cm{sup -1} upon {sup 12}C/{sup 13}C substitution to 14.8 cm{sup -1} for carboxy H/D substitution. The degree of excitonic localization/delocalization can be sensitively measured via the relative intensities of the S{sub 1} Leftwards-Arrow S{sub 0} and S{sub 2} Leftwards-Arrow S{sub 0} origin bands; near-complete localization is observed even for a single {sup 12}C/{sup 13}C substitution. The S{sub 1}/ S{sub 2} energy gap of (BZA){sub 2} is {Delta}{sub calc}{sup exc}=11 cm{sup -1} when calculated by the approximate second-order perturbation theory (CC2) method. Upon correction for vibronic

  16. Laboratory Test Report for Fujitsu 12RLS and Mitsubishi FE12NA Mini-Split Heat Pumps

    SciTech Connect (OSTI)

    Winkler, J.

    2011-09-01

    Mini-split heat pumps are being proposed as a new retrofit option to replace resistance heating in the Pacific Northwest. NREL has previously developed a field test protocol for mini-split systems to ensure consistent results from field tests. This report focuses on the development of detailed system performance maps for mini-split heat pumps so that the potential benefits of mini-split systems can be accurately analyzed for different climate regions and housing types. This report presents laboratory test results for two mini-split heat pumps. Steady-state heating and cooling performance for the Fujitsu 12RLS and Mitsubishi FE12NA was tested under a wide range of outdoor and indoor temperatures at various compressor and fan speeds. Cycling performance for each unit was also tested under both modes of operation. Both systems performed quite well under low loads and the experimental test data aligned with manufacturer reported values. Adequate datasets were attained to promote performance modeling of these two systems in the future.

  17. Energy levels and zero field splitting parameter for Fe{sup 2+} doped in ZnS

    SciTech Connect (OSTI)

    Ivaşcu, Simona

    2013-11-13

    The aim of present paper is to report the results on the modeling of the crystal field parameters of Fe{sup 2+} doped in host matrix ZnS, simulate the energy levels scheme and calculate the zero field splitting parameter D of such system. The crystal field parameters were modeled in the frame of the superposition model of crystal field and the simulation of the energy levels scheme and calculation of the zero field splitting parameters done by diagonalization the Hamiltonian of Fe{sup 2+}:ZnS system. The obtained results were disscused and compared with experimental data. Satisfactory agreement have been obtained.

  18. High Efficiency Hydrogen Production from Nuclear Energy: Laboratory Demonstration of S-I Water-Splitting

    SciTech Connect (OSTI)

    Buckingham, R.; Russ, B.; Brown, L.; Besenbruch, G.E.; Gelbard, F.; Pickard F.S.; Leybros, J.; Le Duigou, A.; Borgard, J.M.

    2004-11-30

    The objective of the French CEA, US-DOE INERI project is to perform a lab scale demonstration of the sulfur iodine (S-I) water splitting cycle, and assess the potential of this cycle for application to nuclear hydrogen production. The project will design, construct and test the three major component reaction sections that make up the S-I cycle. The CEA will design and test the prime (Bunsen) reaction section. General Atomics will develop and test the HI decomposition section, and SNL will develop and test the H2SO4 decomposition section. Activities for this period included initial program coordination and information exchange, the development of models and analyses that will support the design of the component sections, and preliminary designs for the component reaction sections. The sections are being designed to facilitate integration into a closed loop demonstration in a later stage of the program.

  19. Long-Term Monitoring of Mini-Split Ductless Heat Pumps in the Northeast

    SciTech Connect (OSTI)

    Ueno, K.; Loomis, H.

    2015-06-01

    Transformations, Inc. has extensive experience building their high performance housing at a variety of Massachusetts locations, in both a production and custom home setting. The majority of their construction uses mini-split heat pumps (MSHPs) for space conditioning. This research covered the long-term performance of MSHPs in Zone 5A; it is the culmination of up to 3 years' worth of monitoring in a set of eight houses. This research examined electricity use of MSHPs, distributions of interior temperatures and humidity when using simplified (two-point) heating systems in high-performance housing, and the impact of open-door/closed-door status on temperature distributions. The use of simplified space conditioning distribution (through use of MSHPs) provides significant first cost savings, which are used to offset the increased investment in the building enclosure.

  20. The mass splittings of SU(3) baryons within a chiral soliton model

    SciTech Connect (OSTI)

    Yang, Ghil-Seok; Kim, Hyun-Chul

    2011-10-21

    In the framework of a chiral soliton model ({sub {chi}S}M), the complete mass splittings of SU(3) baryons are investigated, the isospin and SU(3) flavor symmetry breaking being simultaneously considered with a 'model-independent approach'. The dynamical quantities appearing in the expressions for the masses are adjusted to the masses of the baryon octet, the decuplet baryon {Sigma}* and the masses of {Theta}{sup +} and N{sup *} as inputs rather than by extracting them from a calculated self-consistent soliton profile. We estimate the masses of the baryon decuplet and antidecuplet without any further adjustable free parameter and it turns out that calculated mass values of the baryon decuplet are in very good agreement with experimental data.

  1. Circuit model optimization of a nano split ring resonator dimer antenna operating in infrared spectral range

    SciTech Connect (OSTI)

    Gneiding, N.; Zhuromskyy, O.; Peschel, U.; Shamonina, E.

    2014-10-28

    Metamaterials are comprised of metallic structures with a strong response to incident electromagnetic radiation, like, for example, split ring resonators. The interaction of resonator ensembles with electromagnetic waves can be simulated with finite difference or finite elements algorithms, however, above a certain ensemble size simulations become inadmissibly time or memory consuming. Alternatively a circuit description of metamaterials, a well developed modelling tool at radio and microwave frequencies, allows to significantly increase the simulated ensemble size. This approach can be extended to the IR spectral range with an appropriate set of circuit element parameters accounting for physical effects such as electron inertia and finite conductivity. The model is verified by comparing the coupling coefficients with the ones obtained from the full wave numerical simulations, and used to optimize the nano-antenna design with improved radiation characteristics.

  2. First-principles thermodynamic screening approach to photo-catalytic water splitting with co-catalysts

    SciTech Connect (OSTI)

    Oberhofer, Harald; Reuter, Karsten

    2013-07-28

    We adapt the computational hydrogen electrode approach to explicitly account for photo-generated charges and use it to computationally screen for viable catalyst/co-catalyst combinations for photo-catalytic water splitting. The hole energy necessary to thermodynamically drive the reaction is employed as descriptor for the screening process. Using this protocol and hybrid-level density-functional theory, we show that water oxidation on bare TiO{sub 2} surfaces is thermodynamically more complex than previously thought. This motivates a screening for suitable co-catalysts for this half-reaction, which we carry out for Au particles down to the non-scalable size regime. We find that almost all small Au clusters studied are better suited for water photo-oxidation than an extended Au(111) surface or bare TiO{sub 2} facets.

  3. A Fully Integrated Nanosystem of Semiconductor Nanowires for Direct Solar Water Splitting

    SciTech Connect (OSTI)

    Liu, Chong; Tang, Jinyao; Chen, HaoMing; Liu, Bin; Yang, Peidong

    2013-02-21

    Artificial photosynthesis, the biomimetic approach to converting sunlight?s energy directly into chemical fuels, aims to imitate nature by using an integrated system of nanostructures, each of which plays a specific role in the sunlight-to-fuel conversion process. Here we describe a fully integrated system of nanoscale photoelectrodes assembled from inorganic nanowires for direct solar water splitting. Similar to the photosynthetic system in a chloroplast, the artificial photosynthetic system comprises two semiconductor light absorbers with large surface area, an interfacial layer for charge transport, and spatially separated cocatalysts to facilitate the water reduction and oxidation. Under simulated sunlight, a 0.12percent solar-to-fuel conversion efficiency is achieved, which is comparable to that of natural photosynthesis. The result demonstrates the possibility of integrating material components into a functional system that mimics the nanoscopic integration in chloroplasts. It also provides a conceptual blueprint of modular design that allows incorporation of newly discovered components for improved performance.

  4. Antiferromagnetic resonance excitation by terahertz magnetic field resonantly enhanced with split ring resonator

    SciTech Connect (OSTI)

    Mukai, Y.; Hirori, H.; Yamamoto, T.; Kageyama, H.; Tanaka, K.

    2014-07-14

    Excitation of antiferromagnetic resonance (AFMR) in a HoFeO{sub 3} crystal combined with a split ring resonator (SRR) is studied using terahertz (THz) electromagnetic pulses. The magnetic field in the vicinity of the SRR is induced by the incident THz electric field component and excites spin oscillations that correspond to the AFMR, which are directly probed by the Faraday rotation of the polarization of a near-infrared probe pulse. The good agreement of the temperature-dependent magnetization dynamics with the calculation using the two-lattice Landau-Lifshitz-Gilbert equation confirms that the AFMR is excited by the THz magnetic field, which is enhanced at the SRR resonance frequency by a factor of 20 compared to the incident magnetic field.

  5. Flux-vector splitting algorithm for chain-rule conservation-law form

    SciTech Connect (OSTI)

    Shih, T.I.-P.; Nguyen, H.L.; Willis, E.A.; Steinthorsson, E.; Li, Z. NASA, Lewis Research Center, Cleveland, OH )

    1991-07-01

    A flux-vector splitting algorithm with Newton-Raphson iteration was developed for the 'full compressible' Navier-Stokes equations cast in chain-rule conservation-law form. The algorithm is intended for problems with deforming spatial domains and for problems whose governing equations cannot be cast in strong conservation-law form. The usefulness of the algorithm for such problems was demonstrated by applying it to analyze the unsteady, two- and three-dimensional flows inside one combustion chamber of a Wankel engine under nonfiring conditions. Solutions were obtained to examine the algorithm in terms of conservation error, robustness, and ability to handle complex flows on time-dependent grid systems. 16 refs.

  6. Splitting of magnetic dipole modes in anisotropic TiO2 micro-spheres

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

    Khromova, Irina; Kuzel, Petr; Brener, Igal; Reno, John L.; Chung Seu, U-Chan; Elissalde, Catherine; Maglione, Mario; Mounaix, Patrick; Mitrofanov, Oleg

    2016-06-27

    Monocrystalline titanium dioxide (TiO2) micro-spheres support two orthogonal magnetic dipole modes at terahertz (THz) frequencies due to strong dielectric anisotropy. For the first time, we experimentally detected the splitting of the first Mie mode in spheres of radii inline imagem through near-field time-domain THz spectroscopy. By fitting the Fano lineshape model to the experimentally obtained spectra of the electric field detected by the sub-wavelength aperture probe, we found that the magnetic dipole resonances in TiO2 spheres have narrow linewidths of only tens of gigahertz. Lastly, anisotropic TiO2 micro-resonators can be used to enhance the interplay of magnetic and electric dipolemore » resonances in the emerging THz all-dielectric metamaterial technology.« less

  7. Interface-induced heavy-hole/light-hole splitting of acceptors in silicon

    SciTech Connect (OSTI)

    Mol, J. A.; Salfi, J.; Simmons, M. Y.; Rogge, S.; Rahman, R.; Hsueh, Y.; Klimeck, G.; Miwa, J. A.

    2015-05-18

    The energy spectrum of spin-orbit coupled states of individual sub-surface boron acceptor dopants in silicon have been investigated using scanning tunneling spectroscopy at cryogenic temperatures. The spatially resolved tunnel spectra show two resonances, which we ascribe to the heavy- and light-hole Kramers doublets. This type of broken degeneracy has recently been argued to be advantageous for the lifetime of acceptor-based qubits [R. Ruskov and C. Tahan, Phys. Rev. B 88, 064308 (2013)]. The depth dependent energy splitting between the heavy- and light-hole Kramers doublets is consistent with tight binding calculations, and is in excess of 1?meV for all acceptors within the experimentally accessible depth range (<2?nm from the surface). These results will aid the development of tunable acceptor-based qubits in silicon with long coherence times and the possibility for electrical manipulation.

  8. Strain-driven growth of GaAs(111) quantum dots with low fine structure splitting

    SciTech Connect (OSTI)

    Yerino, Christopher D.; Jung, Daehwan; Lee, Minjoo Larry; Simmonds, Paul J.; Liang, Baolai; Huffaker, Diana L.; Schneider, Christian; Unsleber, Sebastian; Vo, Minh; Kamp, Martin; Hfling, Sven

    2014-12-22

    Symmetric quantum dots (QDs) on (111)-oriented surfaces are promising candidates for generating polarization-entangled photons due to their low excitonic fine structure splitting (FSS). However, (111) QDs are difficult to grow. The conventional use of compressive strain to drive QD self-assembly fails to form 3D nanostructures on (111) surfaces. Instead, we demonstrate that (111) QDs self-assemble under tensile strain by growing GaAs QDs on an InP(111)A substrate. Tensile GaAs self-assembly produces a low density of QDs with a symmetric triangular morphology. Coherent, tensile QDs are observed without dislocations, and the QDs luminescence at room temperature. Single QD measurements reveal low FSS with a median value of 7.6??eV, due to the high symmetry of the (111) QDs. Tensile self-assembly thus offers a simple route to symmetric (111) QDs for entangled photon emitters.

  9. A study of shock mitigating materials in a split Hopkinson bar configuration

    SciTech Connect (OSTI)

    Bateman, V.I.; Bell, R.G. III; Brown, F.A.; Hansen, N.R.

    1996-12-31

    Sandia National Laboratories (SNL) designs mechanical systems with electronics that must survive high shock environments. These mechanical systems include penetrators that must survive soil, rock, and ice penetration, nuclear transportation casks that must survive transportation environments, and laydown weapons that must survive delivery impact of 125-fps. These mechanical systems contain electronics that may operate during and after the high shock environment and that must be protected from the high shock environments. A study has been started to improve the packaging techniques for the advanced electronics utilized in these mechanical systems because current packaging techniques are inadequate for these more sensitive electronics. In many cases, it has been found that the packaging techniques currently used not only do not mitigate the shock environment but actually amplify the shock environment. An ambitious goal for this packaging study is to avoid amplification and possibly attenuate the shock environment before it reaches the electronics contained in the various mechanical system. As part of the investigation of packaging techniques, a two part study of shock mitigating materials is being conducted. This paper reports the first part of the shock mitigating materials study. A study to compare three thicknesses (0.125, 0.250, and 0.500 in.) of seventeen, unconfined materials for their shock mitigating characteristics has been completed with a split Hopkinson bar configuration. The nominal input as measured by strain gages on the incident Hopkinson bar is 50 fps {at} 100 {micro}s for these tests. It is hypothesized that a shock mitigating material has four purposes: to lengthen the shock pulse, to attenuate the shock pulse, to mitigate high frequency content in the shock pulse, and to absorb energy. Both time domain and frequency domain analyses of the split Hopkinson bar data have been performed to compare the materials` achievement of these purposes.

  10. A study of shock mitigating materials in a split Hopkins bar configuration. Phase 2

    SciTech Connect (OSTI)

    Bateman, V.I.; Brown, F.A.; Hansen, N.R.

    1997-12-31

    Sandia National Laboratories (SNL) designs mechanical systems with electronics that must survive high shock environments. These mechanical systems include penetrators that must survive soil and rock penetration, nuclear transportation casks that must survive transportation environments, and laydown weapons that must survive delivery impact. These mechanical systems contain electronics that may operate during and after the high shock environment and that must be protected from the high shock environments. A study has been started to improve the packaging techniques for the advanced electronics utilized in these mechanical systems because current packaging techniques are inadequate for these sensitive electronics. In many cases, it has been found that the packaging techniques currently used not only do not mitigate the shock environment but actually amplify the shock environment. An ambitious goal for this packaging study is to avoid amplification and possibly attenuate the shock environment before it reached the electronics contained in the various mechanical systems. Here, a study to compare two thickness values, 0.125 and 0.250 in. of five materials, GE RTV 630, HS II Silicone, Polysulfide Rubber, Sylgard 184, and Teflon for their shock mitigating characteristics with a split Hopkinson bar configuration has been completed. The five materials have been tested in both unconfined and confined conditions at ambient temperature and with two applied loads of 750 {mu}{epsilon} peak (25 fps peak) with a 100 {micro}s duration, measured at 10% amplitude, and 1500 {mu}{epsilon} peak (50 fps peak) with a 100 {micro}s duration, measured at 10% amplitude. The five materials have been tested at ambient, cold ({minus}65 F), and hot (+165 F) for the unconfined condition with the 750 {mu}{epsilon} peak (25 fps peak) applied load. Time domain and frequency domain analyses of the split Hopkinson bar data have been performed to compare how these materials lengthen the shock pulse