National Library of Energy BETA

Sample records for loss torque converter

  1. Torque/Moab vs. SLURM Comparisons

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

    Users TorqueMoab vs. SLURM Comparisons TorqueMoab vs. SLURM Comparisons TORQUE vs. SLURM Comparison Tables MoabTorque vs. Slurm Environment Variables Description MoabTorque ...

  2. Spin-Torque

    Office of Scientific and Technical Information (OSTI)

    Spin-Torque in Systems with Inhomogeneous Magnetization Grant No. DE-FG02-04ER46170 Final ... I. OVERVIEW The work performed under this grant focused on the phenomenon of spin-transfer ...

  3. Fabricated torque shaft

    SciTech Connect (OSTI)

    Mashey, Thomas Charles

    2002-01-01

    A fabricated torque shaft is provided that features a bolt-together design to allow vane schedule revisions with minimal hardware cost. The bolt-together design further facilitates on-site vane schedule revisions with parts that are comparatively small. The fabricated torque shaft also accommodates stage schedules that are different one from another in non-linear inter-relationships as well as non-linear schedules for a particular stage of vanes.

  4. DSA torque test robot

    SciTech Connect (OSTI)

    McMillan, D.E.

    1990-11-01

    A rotary solenoid used in the Dual Strong-Link Assembly (DSA) has a housing diameter of 0.67 inches, and overall length of approximately 1.37 inches. The rotor and housing each have four poles. When the coil is energized and the shaft is rotated, magnetic torque is produced which completes four nominally identical cycles during each revolution of the shaft. At zero and 90 degrees of shaft rotation, the poles are aligned and the rotor is stable. The mid-point between poles is unstable; any displacement produces a torque toward one of the stable points. A torque measurement is performed on each solenoid produced. The measurement technique used previously was labor intensive and required that analog torque plots be manually interpreted to determine compliance with the torque specification. This paper describes a robotically assisted torque measurement system that was developed and placed into production. This system reduces cycle time from approximately 6 minutes per part to a little more than 1 minute per part.

  5. Beam converter

    DOE Patents [OSTI]

    Poulsen, Peter

    2003-05-06

    A converter and method for converting electron energy to irradiative energy comprising foam and/or foil. Foam and foil optionally comprise a high-Z material, such as, but not limited to, tantalum.

  6. XTL Converter

    Energy Science and Technology Software Center (OSTI)

    2015-10-07

    "XTL Converter" is a short Python script for electron microscopy simulation. The program takes an input crystal file in the VESTA *.XTL format and converts it to a text format readable by the multislice simulation program ìSTEM. The process of converting a crystal *.XTL file to the format used by the ìSTEM simulation program is quite tedious; it generally requires the user to select dozens or hundreds of atoms, rearranging and reformatting their position. Headermore » information must also be reformatted to a specific style to be read by ìSTEM. "XTL Converter" simplifies this process, saving the user time and allowing for easy batch processing of crystals.« less

  7. Thermionic converter

    DOE Patents [OSTI]

    Fitzpatrick, G.O.

    1987-05-19

    A thermionic converter is set forth which includes an envelope having an electron collector structure attached adjacent to a wall. An electron emitter structure is positioned adjacent the collector structure and spaced apart from opposite wall. The emitter and collector structures are in a common chamber. The emitter structure is heated substantially only by thermal radiation. Very small interelectrode gaps can be maintained utilizing the thermionic converter whereby increased efficiency results. 10 figs.

  8. NovaTorque | Open Energy Information

    Open Energy Info (EERE)

    NovaTorque Jump to: navigation, search Logo: NovaTorque Name: NovaTorque Address: 145 N. Wolfe Road Place: Sunnyvale, California Zip: 94086 Region: Bay Area Sector: Efficiency...

  9. Thermionic converter

    DOE Patents [OSTI]

    Fitzpatrick, Gary O.

    1987-05-19

    A thermionic converter (10) is set forth which includes an envelope (12) having an electron collector structure (22) attached adjacent to a wall (16). An electron emitter structure (24) is positioned adjacent the collector structure (22) and spaced apart from opposite wall (14). The emitter (24) and collector (22) structures are in a common chamber (20). The emitter structure (24) is heated substantially only by thermal radiation. Very small interelectrode gaps (28) can be maintained utilizing the thermionic converter (10) whereby increased efficiency results.

  10. Quick torque coupling

    DOE Patents [OSTI]

    Luft, Peter A.

    2009-05-12

    A coupling for mechanically connecting modular tubular struts of a positioning apparatus or space frame, comprising a pair of toothed rings (10, 12) attached to separate strut members (16), the teeth (18, 20) of the primary rings (10, 12) mechanically interlocking in both an axial and circumferential manner, and a third part comprising a sliding, toothed collar (14) the teeth (22) of which interlock the teeth (18, 20) of the primary rings (10, 12), preventing them from disengaging, and completely locking the assembly together. A secondary mechanism provides a nesting force for the collar, and/or retains it. The coupling is self-contained and requires no external tools for installation, and can be assembled with gloved hands in demanding environments. No gauging or measured torque is required for assembly. The assembly can easily be visually inspected to determine a "go" or "no-go" status. The coupling is compact and relatively light-weight. Because of it's triply interlocking teeth, the connection is rigid. The connection does not primarily rely on clamps, springs or friction based fasteners, and is therefore reliable in fail-safe applications.

  11. Robot-assisted torque measurement

    SciTech Connect (OSTI)

    Lembke, J.R.

    1986-03-01

    An Intelledex 605T robot was used to evaluate the feasibility of automating the measurement of rotary solenoid torque, with the goal of improving productivity. The solenoid chosen for the evaluation is expected to be produced in relatively large quantities for several programs. A new measurement concept was devised, in which the robot connects the solenoid shaft to a torque sensor, rotates the solenoid housing, and correlates rotational data with digitized torque measurements. Prototype tooling was designed and fabricated, and the measurement concept was evaluated in comparison with the manual method which is presently used. The automatic robot-based measurement system was shown to yield results that are in good agreement with manual measurements. The technique automatically performs all necessary operations once the solenoids have been placed into a part loading fixture, with a cycle time significantly reduced from the manual method. Manual interpretation of chart data is not required, because the results are digitized. The system can compare the measured torque to specification limits and can provide a printed report of acceptance or rejection. 12 figs.

  12. Thermionic converter

    DOE Patents [OSTI]

    Rasor, Ned S.; Britt, Edward J.

    1976-01-01

    A gas-filled thermionic converter is provided with a collector and an emitter having a main emitter region and an auxiliary emitter region in electrical contact with the main emitter region. The main emitter region is so positioned with respect to the collector that a main gap is formed therebetween and the auxiliary emitter region is so positioned with respect to the collector that an auxiliary gap is formed therebetween partially separated from the main gap with access allowed between the gaps to allow ionizable gas in each gap to migrate therebetween. With heat applied to the emitter the work function of the auxiliary emitter region is sufficiently greater than the work function of the collector so that an ignited discharge occurs in the auxiliary gap and the work function of the main emitter region is so related to the work function of the collector that an unignited discharge occurs in the main gap sustained by the ions generated in the auxiliary gap. A current flows through a load coupled across the emitter and collector due to the unignited discharge in the main gap.

  13. Torque/Moab vs. SLURM Comparisons

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

    Users » Torque/Moab vs. SLURM Comparisons Torque/Moab vs. SLURM Comparisons TORQUE vs. SLURM Comparison Tables Moab/Torque vs. Slurm Environment Variables Description Moab/Torque Slurm Job Id $PBS_JOBID $SLURM_JOB_ID Job Name $PBS_JOBNAME $SLURM_JOB_NAME Submit Directory $PBS_O_WORKDIR $SLURM_SUBMIT_DIR Node List $PBS_NODEFILE $SLURM_NODELIST Host submitted from $PBS_O_HOST $SLURM_SUBMIT_HOST Nodes allocated $PBS_NUM_NODES $SLURM_JOB_NUM_NODES Number cores/nodes $PBS_NUM_PPN $SLURM_CPUS_ON_NODE

  14. Clustering of cycloidal wave energy converters

    DOE Patents [OSTI]

    Siegel, Stefan G.

    2016-03-29

    A wave energy conversion system uses a pair of wave energy converters (WECs) on respective active mountings on a floating platform, so that the separation of the WECs from each other or from a central WEC can be actively adjusted according to the wavelength of incident waves. The adjustable separation facilitates operation of the system to cancel reactive forces, which may be generated during wave energy conversion. Modules on which such pairs of WECs are mounted can be assembled with one or more central WECs to form large clusters in which reactive forces and torques can be made to cancel. WECs of different sizes can be employed to facilitate cancelation of reactive forces and torques.

  15. Torque limited drive for manual valves

    DOE Patents [OSTI]

    Elliott, Philip G.; Underwood, Daniel E.

    1989-01-01

    The present invention is directed to a torque-limiting handwheel device for preventing manual valves from being damaged due to the application of excessive torque during the opening or closing operation of the valves. Torque can only be applied when ridges in the handwheel assembly engage in channels machined in the face of the baseplate. The amount of torque required for disengagement of the ridges from the channels is determined by the force exerted by various Bellville springs and the inclination of the side faces of the channels.

  16. Torque limited drive for manual valves

    DOE Patents [OSTI]

    Elliott, Philip G.; Underwood, Daniel E.

    1989-06-06

    The present invention is directed to a torque-limiting handwheel device for preventing manual valves from being damaged due to the application of excessive torque during the opening or closing operation of the valves. Torque can only be applied when ridges in the handwheel assembly engage in channels machined in the face of the baseplate. The amount of torque required for disengagement of the ridges from the channels is determined by the force exerted by various Bellville springs and the inclination of the side faces of the channels.

  17. In-line rotating capacitive torque sensor

    DOE Patents [OSTI]

    Kronberg, James W.

    1991-01-01

    A method and apparatus for measuring torques developed along a rotating mechanical assembly comprising a rotating inner portion and a stationary outer portion. The rotating portion has an electrically-conductive flexing section fitted between two coaxial shafts in a configuration which varies radially in accordance with applied torque. The stationary portion comprises a plurality of conductive plates forming a surface concentric with and having a diameter slightly larger than the diameter of the rotating portion. The capacitance between the outer, nonrotating and inner, rotating portion varies with changes in the radial configuration of the rotating portion. Signal output varies approximately linearly with torque for small torques, nonlinearly for larger torques. The sensor is preferably surrounded by a conductive shell to minimize electrical interference from external sources.

  18. In-line rotating capacitive torque sensor

    DOE Patents [OSTI]

    Kronberg, J.W.

    1991-09-10

    Disclosed are a method and apparatus for measuring torques developed along a rotating mechanical assembly comprising a rotating inner portion and a stationary outer portion. The rotating portion has an electrically-conductive flexing section fitted between two coaxial shafts in a configuration which varies radially in accordance with applied torque. The stationary portion comprises a plurality of conductive plates forming a surface concentric with and having a diameter slightly larger than the diameter of the rotating portion. The capacitance between the outer, nonrotating and inner, rotating portion varies with changes in the radial configuration of the rotating portion. Signal output varies approximately linearly with torque for small torques, nonlinearly for larger torques. The sensor is preferably surrounded by a conductive shell to minimize electrical interference from external sources. 18 figures.

  19. RADIOACTIVE MATERIAL PACKAGING TORQUE REQUIREMENTS COMPLIANCE

    SciTech Connect (OSTI)

    Watkins, R.; Leduc, D.

    2011-03-24

    Shipping containers used to transport radioactive material (RAM) in commerce employ a variety of closure mechanisms. Often, these closure mechanisms require a specific amount of torque be applied to a bolt, nut or other threaded fastener. It is important that the required preload is achieved so that the package testing and analysis is not invalidated for the purpose of protecting the public. Torque compliance is a means of ensuring closure preload, is a major factor in accomplishing the package functions of confinement/containment, sub-criticality, and shielding. This paper will address the importance of applying proper torque to package closures, discuss torque value nomenclature, and present one methodology to ensure torque compliance is achieved.

  20. Hybrid switch for resonant power converters

    DOE Patents [OSTI]

    Lai, Jih-Sheng; Yu, Wensong

    2014-09-09

    A hybrid switch comprising two semiconductor switches connected in parallel but having different voltage drop characteristics as a function of current facilitates attainment of zero voltage switching and reduces conduction losses to complement reduction of switching losses achieved through zero voltage switching in power converters such as high-current inverters.

  1. Large amplitude oscillation of magnetization in spin-torque oscillator stabilized by field-like torque

    SciTech Connect (OSTI)

    Taniguchi, Tomohiro Kubota, Hitoshi; Imamura, Hiroshi; Tsunegi, Sumito

    2015-05-07

    Oscillation frequency of spin torque oscillator with a perpendicularly magnetized free layer and an in-plane magnetized pinned layer is theoretically investigated by taking into account the field-like torque. It is shown that the field-like torque plays an important role in finding the balance between the energy supplied by the spin torque and the dissipation due to the damping, which results in a steady precession. The validity of the developed theory is confirmed by performing numerical simulations based on the Landau-Lifshitz-Gilbert equation.

  2. Interleaved power converter

    DOE Patents [OSTI]

    Zhu, Lizhi

    2007-11-13

    A power converter architecture interleaves full bridge converters to alleviate thermal management problems in high current applications, and may, for example, double the output power capability while reducing parts count and costs. For example, one phase of a three phase inverter is shared between two transformers, which provide power to a rectifier such as a current doubler rectifier to provide two full bridge DC/DC converters with three rather than four high voltage inverter legs.

  3. Universal thermochemical energy converter

    DOE Patents [OSTI]

    Labinov, Solomon Davidovich; Sand, James R.; Conklin, James C.; VanCoevering, James; Courville, George E.

    2001-01-01

    Disclosed are methods and apparatus for a thermochemical closed cycle employing a polyatomic, chemically active working fluid for converting heat energy into useful work.

  4. Self-oscillation in spin torque oscillator stabilized by field-like torque

    SciTech Connect (OSTI)

    Taniguchi, Tomohiro; Tsunegi, Sumito; Kubota, Hitoshi; Imamura, Hiroshi

    2014-04-14

    The effect of the field-like torque on the self-oscillation of the magnetization in spin torque oscillator with a perpendicularly magnetized free layer was studied theoretically. A stable self-oscillation at zero field is excited for negative β while the magnetization dynamics stops for β = 0 or β > 0, where β is the ratio between the spin torque and the field-like torque. The reason why only the negative β induces the self-oscillation was explained from the view point of the energy balance between the spin torque and the damping. The oscillation power and frequency for various β were also studied by numerical simulation.

  5. Torque shudder protection device and method

    DOE Patents [OSTI]

    King, Robert D.; De Doncker, Rik W. A. A.; Szczesny, Paul M.

    1997-01-01

    A torque shudder protection device for an induction machine includes a flux command generator for supplying a steady state flux command and a torque shudder detector for supplying a status including a negative status to indicate a lack of torque shudder and a positive status to indicate a presence of torque shudder. A flux adapter uses the steady state flux command and the status to supply a present flux command identical to the steady state flux command for a negative status and different from the steady state flux command for a positive status. A limiter can receive the present flux command, prevent the present flux command from exceeding a predetermined maximum flux command magnitude, and supply the present flux command to a field oriented controller. After determining a critical electrical excitation frequency at which a torque shudder occurs for the induction machine, a flux adjuster can monitor the electrical excitation frequency of the induction machine and adjust a flux command to prevent the monitored electrical excitation frequency from reaching the critical electrical excitation frequency.

  6. Torque shudder protection device and method

    DOE Patents [OSTI]

    King, R.D.; Doncker, R.W.A.A. De.; Szczesny, P.M.

    1997-03-11

    A torque shudder protection device for an induction machine includes a flux command generator for supplying a steady state flux command and a torque shudder detector for supplying a status including a negative status to indicate a lack of torque shudder and a positive status to indicate a presence of torque shudder. A flux adapter uses the steady state flux command and the status to supply a present flux command identical to the steady state flux command for a negative status and different from the steady state flux command for a positive status. A limiter can receive the present flux command, prevent the present flux command from exceeding a predetermined maximum flux command magnitude, and supply the present flux command to a field oriented controller. After determining a critical electrical excitation frequency at which a torque shudder occurs for the induction machine, a flux adjuster can monitor the electrical excitation frequency of the induction machine and adjust a flux command to prevent the monitored electrical excitation frequency from reaching the critical electrical excitation frequency. 5 figs.

  7. Torque limit of PM motors for field-weakening region operation

    DOE Patents [OSTI]

    Royak, Semyon; Harbaugh, Mark M.

    2012-02-14

    The invention includes a motor controller and technique for controlling a permanent magnet motor. In accordance with one aspect of the present technique, a permanent magnet motor is controlled by receiving a torque command, determining a physical torque limit based on a stator frequency, determining a theoretical torque limit based on a maximum available voltage and motor inductance ratio, and limiting the torque command to the smaller of the physical torque limit and the theoretical torque limit. Receiving the torque command may include normalizing the torque command to obtain a normalized torque command, determining the physical torque limit may include determining a normalized physical torque limit, determining a theoretical torque limit may include determining a normalized theoretical torque limit, and limiting the torque command may include limiting the normalized torque command to the smaller of the normalized physical torque limit and the normalized theoretical torque limit.

  8. Microminiature thermionic converters

    DOE Patents [OSTI]

    King, Donald B.; Sadwick, Laurence P.; Wernsman, Bernard R.

    2001-09-25

    Microminiature thermionic converts (MTCs) having high energy-conversion efficiencies and variable operating temperatures. Methods of manufacturing those converters using semiconductor integrated circuit fabrication and micromachine manufacturing techniques are also disclosed. The MTCs of the invention incorporate cathode to anode spacing of about 1 micron or less and use cathode and anode materials having work functions ranging from about 1 eV to about 3 eV. Existing prior art thermionic converter technology has energy conversion efficiencies ranging from 5-15%. The MTCs of the present invention have maximum efficiencies of just under 30%, and thousands of the devices can be fabricated at modest costs.

  9. SPIN-TORQUE IN SYSTEMS WITH INHOMOGENEOUS MAGETIZATION (Technical...

    Office of Scientific and Technical Information (OSTI)

    Title: SPIN-TORQUE IN SYSTEMS WITH INHOMOGENEOUS MAGETIZATION The work performed during the grant period focused on the phenomenon of spin-transfer torque. This is a quantum ...

  10. Torque-balanced vibrationless rotary coupling

    DOE Patents [OSTI]

    Miller, Donald M. (Sunnyside, WA)

    1980-01-01

    This disclosure describes a torque-balanced vibrationless rotary coupling for transmitting rotary motion without unwanted vibration into the spindle of a machine tool. A drive member drives a driven member using flexible connecting loops which are connected tangentially and at diametrically opposite connecting points through a free floating ring.

  11. Digital scale converter

    DOE Patents [OSTI]

    Upton, Richard G.

    1978-01-01

    A digital scale converter is provided for binary coded decimal (BCD) conversion. The converter may be programmed to convert a BCD value of a first scale to the equivalent value of a second scale according to a known ratio. The value to be converted is loaded into a first BCD counter and counted down to zero while a second BCD counter registers counts from zero or an offset value depending upon the conversion. Programmable rate multipliers are used to generate pulses at selected rates to the counters for the proper conversion ratio. The value present in the second counter at the time the first counter is counted to the zero count is the equivalent value of the second scale. This value may be read out and displayed on a conventional seven-segment digital display.

  12. ARM - Temperature Converter

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

    CalculatorsTemperature Converter Outreach Home Room News Publications Traditional Knowledge Kiosks Barrow, Alaska Tropical Western Pacific Site Tours Contacts Students Study Hall About ARM Global Warming FAQ Just for Fun Meet our Friends Cool Sites Teachers Teachers' Toolbox Lesson Plans Temperature Converter The Fahrenheit scale, invented by German physicist Daniel Gabriel Fahrenheit (1686-1736), is based on 32 °F for the freezing point of water and 212 °F for the boiling point of water. The

  13. Torque ripple in a Darrieus, vertical axis wind turbine

    SciTech Connect (OSTI)

    Reuter, R.C. Jr.

    1980-09-01

    Interaction between a steady wind and a rotating, Darrieus, vertical axis wind turbine produces time periodic aerodynamic loads which cause time dependent torque variations, referred to as torque ripple, to occur in the mechanical link between the turbine and the electrical generator. There is concern for the effect of torque ripple upon fatigue life of drive train components and upon power quality. An analytical solution characterizing the phenomenon of torque ripple has been obtained which is based upon a Fourier expansion of the time dependent features of the problem. Numerical results for torque ripple, some experimental data, determination of acceptable levels and methods of controlling it, are presented and discussed.

  14. Vector generator scan converter

    DOE Patents [OSTI]

    Moore, J.M.; Leighton, J.F.

    1988-02-05

    High printing speeds for graphics data are achieved with a laser printer by transmitting compressed graphics data from a main processor over an I/O channel to a vector generator scan converter which reconstructs a full graphics image for input to the laser printer through a raster data input port. The vector generator scan converter includes a microprocessor with associated microcode memory containing a microcode instruction set, a working memory for storing compressed data, vector generator hardware for drawing a full graphic image from vector parameters calculated by the microprocessor, image buffer memory for storing the reconstructed graphics image and an output scanner for reading the graphics image data and inputting the data to the printer. The vector generator scan converter eliminates the bottleneck created by the I/O channel for transmitting graphics data from the main processor to the laser printer, and increases printer speed up to thirty fold. 7 figs.

  15. Vector generator scan converter

    DOE Patents [OSTI]

    Moore, James M.; Leighton, James F.

    1990-01-01

    High printing speeds for graphics data are achieved with a laser printer by transmitting compressed graphics data from a main processor over an I/O (input/output) channel to a vector generator scan converter which reconstructs a full graphics image for input to the laser printer through a raster data input port. The vector generator scan converter includes a microprocessor with associated microcode memory containing a microcode instruction set, a working memory for storing compressed data, vector generator hardward for drawing a full graphic image from vector parameters calculated by the microprocessor, image buffer memory for storing the reconstructed graphics image and an output scanner for reading the graphics image data and inputting the data to the printer. The vector generator scan converter eliminates the bottleneck created by the I/O channel for transmitting graphics data from the main processor to the laser printer, and increases printer speed up to thirty fold.

  16. Spin-torque switching of a nano-magnet using giant spin hall effect

    SciTech Connect (OSTI)

    Penumatcha, Ashish V. Das, Suprem R.; Chen, Zhihong; Appenzeller, Joerg

    2015-10-15

    The Giant Spin Hall Effect(GSHE) in metals with high spin-orbit coupling is an efficient way to convert charge currents to spin currents, making it well-suited for writing information into magnets in non-volatile magnetic memory as well as spin-logic devices. We demonstrate the switching of an in-plane CoFeB magnet using a combination of GSHE and an external magnetic field. The magnetic field dependence of the critical current is used to estimate the spin hall angle with the help of a thermal activation model for spin-transfer torque switching of a nanomagnet.

  17. Liquid metal thermal electric converter

    DOE Patents [OSTI]

    Abbin, Joseph P.; Andraka, Charles E.; Lukens, Laurance L.; Moreno, James B.

    1989-01-01

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

  18. Linear corotation torques in non-barotropic disks

    SciTech Connect (OSTI)

    Tsang, David

    2014-02-20

    A fully analytic expression for the linear corotation torque to first order in eccentricity for planets in non-barotropic protoplanetary disks is derived, taking into account the effect of disk entropy gradients. This torque formula is applicable to both the co-orbital, corotation torques and the non-co-orbital, corotation torques—for planets in orbits with non-zero eccentricity—in disks where the thermal diffusivity and viscosity are sufficient to maintain the linearity of these interactions. While the co-orbital, corotation torque is important for migration of planets in Type I migration, the non-co-orbital, corotation torque plays an important role in the eccentricity evolution of giant planets that have opened gaps in the disk. The presence of an entropy gradient in the disk can significantly modify the corotation torque in both these cases.

  19. Greenhouse Gases Converted to Fuel

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

    Greenhouse Gases Converted to Fuel Greenhouse Gases Converted to Fuel carbon-conversion-fig-1.jpg Key Challenges: An important strategy for reducing global CO2 emissions calls for...

  20. Cycloidal Wave Energy Converter

    SciTech Connect (OSTI)

    Stefan G. Siegel, Ph.D.

    2012-11-30

    This program allowed further advancing the development of a novel type of wave energy converter, a Cycloidal Wave Energy Converter or CycWEC. A CycWEC consists of one or more hydrofoils rotating around a central shaft, and operates fully submerged beneath the water surface. It operates under feedback control sensing the incoming waves, and converts wave power to shaft power directly without any intermediate power take off system. Previous research consisting of numerical simulations and two dimensional small 1:300 scale wave flume experiments had indicated wave cancellation efficiencies beyond 95%. The present work was centered on construction and testing of a 1:10 scale model and conducting two testing campaigns in a three dimensional wave basin. These experiments allowed for the first time for direct measurement of electrical power generated as well as the interaction of the CycWEC in a three dimensional environment. The Atargis team successfully conducted two testing campaigns at the Texas A&M Offshore Technology Research Center and was able to demonstrate electricity generation. In addition, three dimensional wave diffraction results show the ability to achieve wave focusing, thus increasing the amount of wave power that can be extracted beyond what was expected from earlier two dimensional investigations. Numerical results showed wave cancellation efficiencies for irregular waves to be on par with results for regular waves over a wide range of wave lengths. Using the results from previous simulations and experiments a full scale prototype was designed and its performance in a North Atlantic wave climate of average 30kW/m of wave crest was estimated. A full scale WEC with a blade span of 150m will deliver a design power of 5MW at an estimated levelized cost of energy (LCOE) in the range of 10-17 US cents per kWh. Based on the new results achieved in the 1:10 scale experiments these estimates appear conservative and the likely performance at full scale will

  1. Bidirectional buck boost converter

    DOE Patents [OSTI]

    Esser, A.A.M.

    1998-03-31

    A bidirectional buck boost converter and method of operating the same allows regulation of power flow between first and second voltage sources in which the voltage level at each source is subject to change and power flow is independent of relative voltage levels. In one embodiment, the converter is designed for hard switching while another embodiment implements soft switching of the switching devices. In both embodiments, first and second switching devices are serially coupled between a relatively positive terminal and a relatively negative terminal of a first voltage source with third and fourth switching devices serially coupled between a relatively positive terminal and a relatively negative terminal of a second voltage source. A free-wheeling diode is coupled, respectively, in parallel opposition with respective ones of the switching devices. An inductor is coupled between a junction of the first and second switching devices and a junction of the third and fourth switching devices. Gating pulses supplied by a gating circuit selectively enable operation of the switching devices for transferring power between the voltage sources. In the second embodiment, each switching device is shunted by a capacitor and the switching devices are operated when voltage across the device is substantially zero. 20 figs.

  2. Bidirectional buck boost converter

    DOE Patents [OSTI]

    Esser, Albert Andreas Maria

    1998-03-31

    A bidirectional buck boost converter and method of operating the same allows regulation of power flow between first and second voltage sources in which the voltage level at each source is subject to change and power flow is independent of relative voltage levels. In one embodiment, the converter is designed for hard switching while another embodiment implements soft switching of the switching devices. In both embodiments, first and second switching devices are serially coupled between a relatively positive terminal and a relatively negative terminal of a first voltage source with third and fourth switching devices serially coupled between a relatively positive terminal and a relatively negative terminal of a second voltage source. A free-wheeling diode is coupled, respectively, in parallel opposition with respective ones of the switching devices. An inductor is coupled between a junction of the first and second switching devices and a junction of the third and fourth switching devices. Gating pulses supplied by a gating circuit selectively enable operation of the switching devices for transferring power between the voltage sources. In the second embodiment, each switching device is shunted by a capacitor and the switching devices are operated when voltage across the device is substantially zero.

  3. Spin-transfer torque magnetoresistive random-access memory technologies for normally off computing (invited)

    SciTech Connect (OSTI)

    Ando, K. Yuasa, S.; Fujita, S.; Ito, J.; Yoda, H.; Suzuki, Y.; Nakatani, Y.; Miyazaki, T.

    2014-05-07

    Most parts of present computer systems are made of volatile devices, and the power to supply them to avoid information loss causes huge energy losses. We can eliminate this meaningless energy loss by utilizing the non-volatile function of advanced spin-transfer torque magnetoresistive random-access memory (STT-MRAM) technology and create a new type of computer, i.e., normally off computers. Critical tasks to achieve normally off computers are implementations of STT-MRAM technologies in the main memory and low-level cache memories. STT-MRAM technology for applications to the main memory has been successfully developed by using perpendicular STT-MRAMs, and faster STT-MRAM technologies for applications to the cache memory are now being developed. The present status of STT-MRAMs and challenges that remain for normally off computers are discussed.

  4. Array Converter | Open Energy Information

    Open Energy Info (EERE)

    Converter Place: Sunnyvale, California Zip: 94086 Product: US manufacturer of micro-inverters. Coordinates: 32.780338, -96.547405 Show Map Loading map......

  5. Self-powered microthermionic converter

    DOE Patents [OSTI]

    Marshall, Albert C.; King, Donald B.; Zavadil, Kevin R.; Kravitz, Stanley H.; Tigges, Chris P.; Vawter, Gregory A.

    2004-08-10

    A self-powered microthermionic converter having an internal thermal power source integrated into the microthermionic converter. These converters can have high energy-conversion efficiencies over a range of operating temperatures. Microengineering techniques are used to manufacture the converter. The utilization of an internal thermal power source increases potential for mobility and incorporation into small devices. High energy efficiency is obtained by utilization of micron-scale interelectrode gap spacing. Alpha-particle emitting radioisotopes can be used for the internal thermal power source, such as curium and polonium isotopes.

  6. Spin torque and Nernst effects in Dzyaloshinskii-Moriya ferromagnets

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

    Kovalev, Alexey A.; Zyuzin, Vladimir

    2016-04-11

    Here, we predict that a temperature gradient can induce a magnon-mediated intrinsic torque in systems with a nontrivial magnon Berry curvature. With the help of a microscopic linear response theory of nonequilibrium magnon-mediated torques and spin currents we identify the interband and intraband components that manifest in ferromagnets with Dzyaloshinskii-Moriya interactions and magnetic textures. To illustrate and assess the importance of such effects, we apply the linear response theory to the magnon-mediated spin Nernst and torque responses in a kagome lattice ferromagnet.

  7. Spin orbit torque based electronic neuron

    SciTech Connect (OSTI)

    Sengupta, Abhronil Choday, Sri Harsha; Kim, Yusung; Roy, Kaushik

    2015-04-06

    A device based on current-induced spin-orbit torque (SOT) that functions as an electronic neuron is proposed in this work. The SOT device implements an artificial neuron's thresholding (transfer) function. In the first step of a two-step switching scheme, a charge current places the magnetization of a nano-magnet along the hard-axis, i.e., an unstable point for the magnet. In the second step, the SOT device (neuron) receives a current (from the synapses) which moves the magnetization from the unstable point to one of the two stable states. The polarity of the synaptic current encodes the excitatory and inhibitory nature of the neuron input and determines the final orientation of the magnetization. A resistive crossbar array, functioning as synapses, generates a bipolar current that is a weighted sum of the inputs. The simulation of a two layer feed-forward artificial neural network based on the SOT electronic neuron shows that it consumes ?3 lower power than a 45?nm digital CMOS implementation, while reaching ?80% accuracy in the classification of 100 images of handwritten digits from the MNIST dataset.

  8. Effects of q -profile structures on intrinsic torque reversals...

    Office of Scientific and Technical Information (OSTI)

    Title: Effects of q -profile structures on intrinsic torque reversals Authors: Lu, Z. X. ; Wang, W. X. ; Diamond, P. H. ; Tynan, G. ; Ethier, S. ; Chen, J. ; Gao, C. ; Rice, J. E. ...

  9. Cycling firing method for bypass operation of bridge converters

    DOE Patents [OSTI]

    Zabar, Zivan

    1982-01-01

    The bridge converter comprises a number of switching elements and an electronic logic system which regulated the electric power levels by controlling the firing, i.e., the initiation of the conduction period of the switching elements. Cyclic firing of said elements allows the direct current to bypass the alternating current system with high power factor and negligible losses.

  10. Boron nitride converted carbon fiber

    DOE Patents [OSTI]

    Rousseas, Michael; Mickelson, William; Zettl, Alexander K.

    2016-04-05

    This disclosure provides systems, methods, and apparatus related to boron nitride converted carbon fiber. In one aspect, a method may include the operations of providing boron oxide and carbon fiber, heating the boron oxide to melt the boron oxide and heating the carbon fiber, mixing a nitrogen-containing gas with boron oxide vapor from molten boron oxide, and converting at least a portion of the carbon fiber to boron nitride.

  11. Heat engine and electric motor torque distribution strategy for a hybrid electric vehicle

    DOE Patents [OSTI]

    Boberg, Evan S.; Gebby, Brian P.

    1999-09-28

    A method is provided for controlling a power train system for a hybrid electric vehicle. The method includes a torque distribution strategy for controlling the engine and the electric motor. The engine and motor commands are determined based upon the accelerator position, the battery state of charge and the amount of engine and motor torque available. The amount of torque requested for the engine is restricted by a limited rate of rise in order to reduce the emissions from the engine. The limited engine torque is supplemented by motor torque in order to meet a torque request determined based upon the accelerator position.

  12. Charge-pump voltage converter

    DOE Patents [OSTI]

    Brainard, John P.; Christenson, Todd R.

    2009-11-03

    A charge-pump voltage converter for converting a low voltage provided by a low-voltage source to a higher voltage. Charge is inductively generated on a transfer rotor electrode during its transit past an inductor stator electrode and subsequently transferred by the rotating rotor to a collector stator electrode for storage or use. Repetition of the charge transfer process leads to a build-up of voltage on a charge-receiving device. Connection of multiple charge-pump voltage converters in series can generate higher voltages, and connection of multiple charge-pump voltage converters in parallel can generate higher currents. Microelectromechanical (MEMS) embodiments of this invention provide a small and compact high-voltage (several hundred V) voltage source starting with a few-V initial voltage source. The microscale size of many embodiments of this invention make it ideally suited for MEMS- and other micro-applications where integration of the voltage or charge source in a small package is highly desirable.

  13. Closed-loop torque feedback for a universal field-oriented controller

    DOE Patents [OSTI]

    De Doncker, R.W.A.A.; King, R.D.; Sanza, P.C.; Haefner, K.B.

    1992-11-24

    A torque feedback system is employed in a universal field-oriented (UFO) controller to tune a torque-producing current command and a slip frequency command in order to achieve robust torque control of an induction machine even in the event of current regulator errors and during transitions between pulse width modulated (PWM) and square wave modes of operation. 1 figure.

  14. Closed-loop torque feedback for a universal field-oriented controller

    DOE Patents [OSTI]

    De Doncker, Rik W. A. A.; King, Robert D.; Sanza, Peter C.; Haefner, Kenneth B.

    1992-01-01

    A torque feedback system is employed in a universal field-oriented (UFO) controller to tune a torque-producing current command and a slip frequency command in order to achieve robust torque control of an induction machine even in the event of current regulator errors and during transitions between pulse width modulated (PWM) and square wave modes of operation.

  15. Portable convertible blast effects shield

    DOE Patents [OSTI]

    Pastrnak, John W.; Hollaway, Rocky; Henning, Carl D.; Deteresa, Steve; Grundler, Walter; Hagler,; Lisle B.; Kokko, Edwin; Switzer, Vernon A

    2010-10-26

    A rapidly deployable portable convertible blast effects shield/ballistic shield includes a set two or more telescoping cylindrical rings operably connected to each other to convert between a telescopically-collapsed configuration for storage and transport, and a telescopically-extended upright configuration forming an expanded inner volume. In a first embodiment, the upright configuration provides blast effects shielding, such as against blast pressures, shrapnel, and/or fire balls. And in a second embodiment, the upright configuration provides ballistic shielding, such as against incoming weapons fire, shrapnel, etc. Each ring has a high-strength material construction, such as a composite fiber and matrix material, capable of substantially inhibiting blast effects and impinging projectiles from passing through the shield. And the set of rings are releasably securable to each other in the telescopically-extended upright configuration, such as by click locks.

  16. Portable convertible blast effects shield

    DOE Patents [OSTI]

    Pastrnak, John W.; Hollaway, Rocky; Henning, Carl D.; Deteresa, Steve; Grundler, Walter; Hagler, Lisle B.; Kokko, Edwin; Switzer, Vernon A.

    2011-03-15

    A rapidly deployable portable convertible blast effects shield/ballistic shield includes a set two or more frusto-conically-tapered telescoping rings operably connected to each other to convert between a telescopically-collapsed configuration for storage and transport, and a telescopically-extended upright configuration forming an expanded inner volume. In a first embodiment, the upright configuration provides blast effects shielding, such as against blast pressures, shrapnel, and/or fire balls. And in a second embodiment, the upright configuration provides ballistic shielding, such as against incoming weapons fire, shrapnel, etc. Each ring has a high-strength material construction, such as a composite fiber and matrix material, capable of substantially inhibiting blast effects and impinging projectiles from passing through the shield. And the set of rings are releasably securable to each other in the telescopically-extended upright configuration by the friction fit of adjacent pairs of frusto-conically-tapered rings to each other.

  17. Portable convertible blast effects shield

    DOE Patents [OSTI]

    Pastrnak, John W.; Hollaway, Rocky; Henning, Carl D.; Deteresa, Steve; Grundler, Walter; Hagler, Lisle B.; Kokko, Edwin; Switzer, Vernon A

    2007-05-22

    A rapidly deployable portable convertible blast effects shield/ballistic shield includes a set two or more telescoping cylindrical rings operably connected to each other to convert between a telescopically-collapsed configuration for storage and transport, and a telescopically-extended upright configuration forming an expanded inner volume. In a first embodiment, the upright configuration provides blast effects shielding, such as against blast pressures, shrapnel, and/or fire balls. And in a second embodiment, the upright configuration provides ballistic shielding, such as against incoming weapons fire, shrapnel, etc. Each ring has a high-strength material construction, such as a composite fiber and matrix material, capable of substantially inhibiting blast effects and impinging projectiles from passing through the shield. And the set of rings are releasably securable to each other in the telescopically-extended upright configuration, such as by click locks.

  18. Speed And Power Control Of An Engine By Modulation Of The Load Torque

    SciTech Connect (OSTI)

    Ziph, Benjamin; Strodtman, Scott; Rose, Thomas K

    1999-01-26

    A system and method of speed and power control for an engine in which speed and power of the engine is controlled by modulation of the load torque. The load torque is manipulated in order to cause engine speed, and hence power to be changed. To accomplish such control, the load torque undergoes a temporary excursion in the opposite direction of the desired speed and power change. The engine and the driven equipment will accelerate or decelerate accordingly as the load torque is decreased or increased, relative to the essentially fixed or constant engine torque. As the engine accelerates or decelerates, its power increases or decreases in proportion.

  19. Enhancement of Spin-transfer torque switching via resonant tunneling

    SciTech Connect (OSTI)

    Chatterji, Niladri; Tulapurkar, Ashwin A.; Muralidharan, Bhaskaran

    2014-12-08

    We propose the use of resonant tunneling as a route to enhance the spin-transfer torque switching characteristics of magnetic tunnel junctions. The proposed device structure is a resonant tunneling magnetic tunnel junction based on a MgO-semiconductor heterostructure sandwiched between a fixed magnet and a free magnet. Using the non-equilibrium Green's function formalism coupled self consistently with the Landau-Lifshitz-Gilbert-Slonczewski equation, we demonstrate enhanced tunnel magneto-resistance characteristics as well as lower switching voltages in comparison with traditional trilayer devices. Two device designs based on MgO based heterostructures are presented, where the physics of resonant tunneling leads to an enhanced spin transfer torque thereby reducing the critical switching voltage by up to 44%. It is envisioned that the proof-of-concept presented here may lead to practical device designs via rigorous materials and interface studies.

  20. Avoidance of Tearing Mode Locking and Disruption with Electro-Magnetic Torque Introduced by Feedback-based Mode Rotation Control in DIII-D and RFX-mod

    SciTech Connect (OSTI)

    Okabayashi, M.; Zanca, P.; Strait, E. J.

    2014-09-01

    Disruptions caused by tearing modes (TMs) are considered to be one of the most critical roadblocks to achieving reliable, steady-state operation of tokamak fusion reactors. Here we have demonstrated a very promising scheme to avoid such disruptions by utilizing the electro-magnetic (EM) torque produced with 3D coils that are available in many tokamaks. In this scheme, the EM torque to the modes is created by a toroidal phase shift between the externally-applied field and the excited TM fields, compensating for the mode momentum loss due to the interaction with the resistive wall and uncorrected error fields. Fine control of torque balance is provided by a feedback scheme. We have explored this approach in two vastly different devices and plasma conditions: DIII-D and RFX-mod operated in tokamak mode. In DIII-D, the plasma target was high βN plasmas in a non-circular divertor tokamak. In RFX-mod, the plasma was ohmically-heated plasma with ultralow safety factor in a circular limiter discharge of active feedback coils outside the thick resistive shell. The DIII-D and RFX-mod experiments showed remarkable consistency with theoretical predictions of torque balance. The application to ignition-oriented devices such as International Thermonuclear Experimental Reactor (ITER) would expand the horizon of its operational regime. The internal 3D coil set currently under consideration for edge localized mode suppression in ITER would be well suited to this purpose.

  1. Angular momentum and torque described with the complex octonion

    SciTech Connect (OSTI)

    Weng, Zi-Hua

    2014-08-15

    The paper aims to adopt the complex octonion to formulate the angular momentum, torque, and force etc in the electromagnetic and gravitational fields. Applying the octonionic representation enables one single definition of angular momentum (or torque, force) to combine some physics contents, which were considered to be independent of each other in the past. J. C. Maxwell used simultaneously two methods, the vector terminology and quaternion analysis, to depict the electromagnetic theory. It motivates the paper to introduce the quaternion space into the field theory, describing the physical feature of electromagnetic and gravitational fields. The spaces of electromagnetic field and of gravitational field can be chosen as the quaternion spaces, while the coordinate component of quaternion space is able to be the complex number. The quaternion space of electromagnetic field is independent of that of gravitational field. These two quaternion spaces may compose one octonion space. Contrarily, one octonion space can be separated into two subspaces, the quaternion space and S-quaternion space. In the quaternion space, it is able to infer the field potential, field strength, field source, angular momentum, torque, and force etc in the gravitational field. In the S-quaternion space, it is capable of deducing the field potential, field strength, field source, current continuity equation, and electric (or magnetic) dipolar moment etc in the electromagnetic field. The results reveal that the quaternion space is appropriate to describe the gravitational features, including the torque, force, and mass continuity equation etc. The S-quaternion space is proper to depict the electromagnetic features, including the dipolar moment and current continuity equation etc. In case the field strength is weak enough, the force and the continuity equation etc can be respectively reduced to that in the classical field theory.

  2. Key-and-keyway coupling for transmitting torque

    DOE Patents [OSTI]

    Blue, S.C.; Curtis, M.T.; Orthwein, W.C.; Stitt, D.H.

    1975-11-18

    The design of an improved key-and-keyway coupling for the transmission of torque is given. The coupling provides significant reductions in stress concentrations in the vicinity of the key and keyway. The keyway is designed with a flat-bottomed u-shaped portion whose inboard end terminates in a ramp which is dished transversely, so that the surface of the ramp as viewed in transverse section defines an outwardly concave arc.

  3. Auxiliary resonant DC tank converter

    DOE Patents [OSTI]

    Peng, Fang Z.

    2000-01-01

    An auxiliary resonant dc tank (ARDCT) converter is provided for achieving soft-switching in a power converter. An ARDCT circuit is coupled directly across a dc bus to the inverter to generate a resonant dc bus voltage, including upper and lower resonant capacitors connected in series as a resonant leg, first and second dc tank capacitors connected in series as a tank leg, and an auxiliary resonant circuit comprising a series combination of a resonant inductor and a pair of auxiliary switching devices. The ARDCT circuit further includes first clamping means for holding the resonant dc bus voltage to the dc tank voltage of the tank leg, and second clamping means for clamping the resonant dc bus voltage to zero during a resonant period. The ARDCT circuit resonantly brings the dc bus voltage to zero in order to provide a zero-voltage switching opportunity for the inverter, then quickly rebounds the dc bus voltage back to the dc tank voltage after the inverter changes state. The auxiliary switching devices are turned on and off under zero-current conditions. The ARDCT circuit only absorbs ripples of the inverter dc bus current, thus having less current stress. In addition, since the ARDCT circuit is coupled in parallel with the dc power supply and the inverter for merely assisting soft-switching of the inverter without participating in real dc power transmission and power conversion, malfunction and failure of the tank circuit will not affect the functional operation of the inverter; thus a highly reliable converter system is expected.

  4. Enterprise converting buses to biodiesel

    Broader source: Energy.gov [DOE]

    Rental car customers may be able to breathe a little easier during their next trip to the airport. Alamo Rent A Car, Enterprise Rent-A-Car, and National Car Rental, all brands operated by the subsidiaries of Enterprise Holdings, are converting their airport shuttle buses to run on biodiesel fuel. The move is a good one for the environment, and will ultimately reduce the company’s carbon emissions. “We are saving 420,000 gallons of petroleum diesel,”  says Lee Broughton, director of corporate identity and sustainability for Enterprise Holdings.    

  5. Design of a high efficiency 30 kW boost composite converter

    SciTech Connect (OSTI)

    Kim, Hyeokjin; Chen, Hua; Maksimovic, Dragan; Erickson, Robert W.

    2015-09-20

    An experimental 30 kW boost composite converter is described in this paper. The composite converter architecture, which consists of a buck module, a boost module, and a dual active bridge module that operates as a DC transformer (DCX), leads to substantial reductions in losses at partial power points, and to significant improvements in weighted efficiency in applications that require wide variations in power and conversion ratio. A comprehensive loss model is developed, accounting for semiconductor conduction and switching losses, capacitor losses, as well as dc and ac losses in magnetic components. Based on the developed loss model, the module and system designs are optimized to maximize efficiency at a 50% power point. Experimental results for the 30 kW prototype demonstrate 98.5%peak efficiency, very high efficiency over wide ranges of power and voltage conversion ratios, as well as excellent agreements between model predictions and measured efficiency curves.

  6. Non-linear mode interaction between spin torque driven and damped modes in spin torque nano-oscillators

    SciTech Connect (OSTI)

    Romera, M.; Monteblanco, E.; Garcia-Sanchez, F.; Buda-Prejbeanu, L. D.; Ebels, U.; Delaët, B.

    2015-05-11

    The influence of dynamic coupling in between magnetic layers of a standard spin torque nano-oscillator composed of a synthetic antiferromagnet (SyF) as a polarizer and an in-plane magnetized free layer has been investigated. Experiments on spin valve nanopillars reveal non-continuous features such as kinks in the frequency field dependence that cannot be explained without such interactions. Comparison of experiments to numerical macrospin simulations shows that this is due to non-linear interaction between the spin torque (STT) driven mode and a damped mode that is mediated via the third harmonics of the STT mode. It only occurs at large applied currents and thus at large excitation amplitudes of the STT mode. Under these conditions, a hybridized mode characterized by a strong reduction of the linewidth appears. The reduced linewidth can be explained by a reduction of the non-linear contribution to the linewidth via an enhanced effective damping. Interestingly, the effect depends also on the exchange interaction within the SyF. An enhancement of the current range of reduced linewidth by a factor of two and a reduction of the minimum linewidth by a factor of two are predicted from simulation when the exchange interaction strength is reduced by 30%. These results open directions to optimize the design and microwave performances of spin torque nano-oscillators taking advantage of the coupling mechanisms.

  7. Thermionic converter emitter support arrangement

    SciTech Connect (OSTI)

    Allen, D.T.

    1990-05-22

    This patent describes a support provided for use in a therminonic converter to support an end of an emitter to keep it out of contact with a surrounding collector while allowing the emitter end to move axially as its temperature changes. The emitter end is supported by a spring structure that includes a pair of Belleville springs, and the spring structure is supported by a support structure fixed to the housing that includes the collector. The support structure is in the form of a sandwich with a small metal spring-engaging element at the front end, a larger metal main support at the rear end that is attached to the housing, and with a ceramic layer between them that is bonded by hot isostatic pressing to the metal element and metal main support. The spring structure can include a loose wafer captured between the Belleville springs.

  8. Thermionic converter emitter support arrangement

    SciTech Connect (OSTI)

    Allen, D.T.

    1989-07-06

    This document discusses a support provided for use in a thermionic converter to support an end of an emitter to keep it out of contact with a surrounding collector while allowing the emitter end to move axially as its temperature changes. The emitter end is supported by a spring structure that includes a pair of Belleville springs, and the spring structure is supported by a support structure fixed to the housing that includes the collector. The support structure is in the form of a sandwich with a small metal spring-engaging element at the front end, a larger metal main support at the rear end that is attached to the housing, and with a ceramic layer between them that is bonded by hot isostatic pressing to the metal element and metal main support. The spring structure can include a loose wafer captured between the Belleville springs. 7 figs.

  9. Thermionic converter emitter support arrangement

    SciTech Connect (OSTI)

    Allen, Daniel T.

    1990-01-01

    A support is provided for use in a thermionic converter to support an end an emitter to keep it out of contact with a surrounding collector while allowing the emitter end to move axially at its temperatures changes. The emitter end (34) is supported by a spring structure (44) that includes a pair of Belleville springs, and the spring structure is supported by a support structure (42) fixed to the housing that includes the collector. The support structure is in the form of a sandwich with a small metal spring-engaging element (74) at the front end, a larger metal main support (76) at the rear end that is attached to the housng, and with a ceramic layer (80) between them that is bonded by hot isostatic pressing to the metal element and metal main support. The spring structure can include a loose wafer (120) captured between the Belleville springs.

  10. Thermionic converter emitter support arrangement

    SciTech Connect (OSTI)

    Allen, Daniel T.

    1990-01-01

    A support is provided for use in a therminonic converter to support an end of an emitter to keep it out of contact with a surrounding collector while allowing the emitter end to move axially as its temperature changes. The emitter end (34) is supported by a spring structure (44) that includes a pair of Belleville springs, and the spring structure is supported by a support structure (42) fixed to the housing that includes the collector. The support structure is in the form of a sandwich with a small metal spring-engaging element (74) at the front end, a larger metal main support (76) at the rear end that is attached to the housing, and with a ceramic layer (80) between them that is bonded by hot isostatic pressing to the metal element and metal main support. The spring structure can include a loose wafer (120) captured between the Belleville springs.

  11. Thermionic converter emitter support arrangement

    SciTech Connect (OSTI)

    Allen, D.T.

    1990-10-16

    A support is presented for use in a thermionic converted to support an end of an emitter to keep it out of contact with a surrounding collector while allowing the emitter end to move axially at its temperatures changes. The emitter end is supported by a spring structure that includes a pair of Belleville springs, and the spring structure is supported by a support structure fixed to the housing that includes the collector. The support structure is in the form of a sandwich with a small metal spring-engaging element at the front end, a large metal main support at the rear end that is attached to the housing, and metal main support. The spring structure can include a loose wafer captured between the Belleville springs.

  12. Torque for electron spin induced by electron permanent electric dipole moment

    SciTech Connect (OSTI)

    Senami, Masato E-mail: akitomo@scl.kyoto-u.ac.jp; Fukuda, Masahiro E-mail: akitomo@scl.kyoto-u.ac.jp; Ogiso, Yoji E-mail: akitomo@scl.kyoto-u.ac.jp; Tachibana, Akitomo E-mail: akitomo@scl.kyoto-u.ac.jp

    2014-10-06

    The spin torque of the electron is studied in relation to the electric dipole moment (EDM) of the electron. The spin dynamics is known to be given by the spin torque and the zeta force in quantum field theory. The effect of the EDM on the torque of the spin brings a new term in the equation of motion of the spin. We study this effect for a solution of the Dirac equation with electromagnetic field.

  13. Sandia Energy - WEC-Sim (Wave Energy Converter SIMulator)

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

    WEC-Sim (Wave Energy Converter SIMulator) Home Stationary Power Energy Conversion Efficiency Water Power WEC-Sim (Wave Energy Converter SIMulator) WEC-Sim (Wave Energy Converter...

  14. In-line rotating torque sensor with on-board amplifier

    DOE Patents [OSTI]

    Kronberg, James W.

    1990-01-01

    A rotating torque sensor apparatus and method for measuring small torques comprising a shaft, a platform having a circuit board and a first moment arm attached to the shaft, a rotatable wheel coaxial with the shaft and having a second moment arm spaced apart from the first moment arm with a load cell therebetween for generating an electric signal as the torque is applied to the shaft and transferred through the moment arms to the load cell. The electrical signal is conducted from the load cell to the circuit board for filtering and amplification before being extracted from the torque assembly through a slip ring.

  15. Multi-Axis Foot Reaction Force/Torque Sensor for Biomedical Applicatio...

    Office of Scientific and Technical Information (OSTI)

    Sponsoring Org: ORNL work for others Country of Publication: United States Language: English Subject: 60 APPLIED LIFE SCIENCES; ROBOTS; FEET; PROSTHESES; SENSORS; DESIGN; TORQUE ...

  16. Universal adaptive torque control for PM motors for field-weakening region operation

    DOE Patents [OSTI]

    Royak, Semyon; Harbaugh, Mark M.; Breitzmann, Robert J.; Nondahl, Thomas A.; Schmidt, Peter B.; Liu, Jingbo

    2011-03-29

    The invention includes a motor controller and method for controlling a permanent magnet motor. In accordance with one aspect of the present technique, a permanent magnet motor is controlled by, among other things, receiving a torque command, determining a normalized torque command by normalizing the torque command to a characteristic current of the motor, determining a normalized maximum available voltage, determining an inductance ratio of the motor, and determining a direct-axis current based upon the normalized torque command, the normalized maximum available voltage, and the inductance ratio of the motor.

  17. Negative space charge effects in photon-enhanced thermionic emission solar converters

    SciTech Connect (OSTI)

    Segev, G.; Weisman, D.; Rosenwaks, Y.; Kribus, A.

    2015-07-06

    In thermionic energy converters, electrons in the gap between electrodes form a negative space charge and inhibit the emission of additional electrons, causing a significant reduction in conversion efficiency. However, in Photon Enhanced Thermionic Emission (PETE) solar energy converters, electrons that are reflected by the electric field in the gap return to the cathode with energy above the conduction band minimum. These electrons first occupy the conduction band from which they can be reemitted. This form of electron recycling makes PETE converters less susceptible to negative space charge loss. While the negative space charge effect was studied extensively in thermionic converters, modeling its effect in PETE converters does not account for important issues such as this form of electron recycling, nor the cathode thermal energy balance. Here, we investigate the space charge effect in PETE solar converters accounting for electron recycling, with full coupling of the cathode and gap models, and addressing conservation of both electric and thermal energy. The analysis shows that the negative space charge loss is lower than previously reported, allowing somewhat larger gaps compared to previous predictions. For a converter with a specific gap, there is an optimal solar flux concentration. The optimal solar flux concentration, the cathode temperature, and the efficiency all increase with smaller gaps. For example, for a gap of 3 μm the maximum efficiency is 38% and the optimal flux concentration is 628, while for a gap of 5 μm the maximum efficiency is 31% and optimal flux concentration is 163.

  18. New Catalyst Converts CO₂ to Fuel

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

    New Catalyst Converts CO₂ to Fuel New Catalyst Converts CO₂ to Fuel Calculations run at NERSC help confirm University of Illinois breakthrough September 5, 2014 Contact: Kathy Kincade, +1 510 495 2124, kkincade@lbl.gov Scientists from the University of Illinois at Chicago have synthesized a catalyst that improves their system for converting waste carbon dioxide (CO₂) into syngas, a precursor of gasoline and other energy-rich products, bringing the process closer to commercial viability.

  19. Ocean floor mounting of wave energy converters

    DOE Patents [OSTI]

    Siegel, Stefan G

    2015-01-20

    A system for mounting a set of wave energy converters in the ocean includes a pole attached to a floor of an ocean and a slider mounted on the pole in a manner that permits the slider to move vertically along the pole and rotate about the pole. The wave energy converters can then be mounted on the slider to allow adjustment of the depth and orientation of the wave energy converters.

  20. Vacuum-insulated catalytic converter

    DOE Patents [OSTI]

    Benson, David K.

    2001-01-01

    A catalytic converter has an inner canister that contains catalyst-coated substrates and an outer canister that encloses an annular, variable vacuum insulation chamber surrounding the inner canister. An annular tank containing phase-change material for heat storage and release is positioned in the variable vacuum insulation chamber a distance spaced part from the inner canister. A reversible hydrogen getter in the variable vacuum insulation chamber, preferably on a surface of the heat storage tank, releases hydrogen into the variable vacuum insulation chamber to conduct heat when the phase-change material is hot and absorbs the hydrogen to limit heat transfer to radiation when the phase-change material is cool. A porous zeolite trap in the inner canister absorbs and retains hydrocarbons from the exhaust gases when the catalyst-coated substrates and zeolite trap are cold and releases the hydrocarbons for reaction on the catalyst-coated substrate when the zeolite trap and catalyst-coated substrate get hot.

  1. Webinar Recording Available: Advanced Wave Energy Converters...

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

    Webinar Recording Available: Advanced Wave Energy Converters (WEC) Dynamics and Controls - ... Secure & Sustainable Energy Future Stationary Power Energy Conversion Efficiency Solar ...

  2. Innovative Catalytic Converter Wins National Award

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

    Golden, Colo., July 25, 1996A new catalytic converter design that could dramatically reduce automobile emissions and urban air pollution has been named one of the years most ...

  3. Controller for a wave energy converter

    SciTech Connect (OSTI)

    Wilson, David G.; Bull, Diana L.; Robinett, III, Rush D.

    2015-09-22

    A wave energy converter (WEC) is described, the WEC including a power take off (PTO) that converts relative motion of bodies of the WEC into electrical energy. A controller controls operation of the PTO, causing the PTO to act as a motor to widen a wave frequency spectrum that is usable to generate electrical energy.

  4. RF digital-to-analog converter

    DOE Patents [OSTI]

    Conway, P.H.; Yu, D.U.L.

    1995-02-28

    A digital-to-analog converter is disclosed for producing an RF output signal proportional to a digital input word of N bits from an RF reference input, N being an integer greater or equal to 2. The converter comprises a plurality of power splitters, power combiners and a plurality of mixers or RF switches connected in a predetermined configuration. 18 figs.

  5. RF digital-to-analog converter

    DOE Patents [OSTI]

    Conway, Patrick H.; Yu, David U. L.

    1995-01-01

    A digital-to analogue converter for producing an RF output signal proportional to a digital input word of N bits from an RF reference input, N being an integer greater or equal to 2. The converter comprises a plurality of power splitters, power combiners and a plurality of mixers or RF switches connected in a predetermined configuration.

  6. Distributed electrical leads for thermionic converter

    DOE Patents [OSTI]

    Fitzpatrick, Gary O.; Britt, Edward J.

    1979-01-01

    In a thermionic converter, means are provided for coupling an electrical lead to at least one of the electrodes thereof. The means include a bus bar and a plurality of distributed leads coupled to the bus bar each of which penetrates through one electrode and are then coupled to the other electrode of the converter in spaced apart relation.

  7. Magnetization reversal driven by a spin torque oscillator

    SciTech Connect (OSTI)

    Sbiaa, R.

    2014-09-01

    Magnetization reversal of a magnetic free layer under spin transfer torque (STT) effect from a magnetic hard layer with a fixed magnetization direction and an oscillating layer is investigated. By including STT from the oscillating layer with in-plane anisotropy and orthogonal polarizer, magnetization-time dependence of free layer is determined. The results show that the frequency and amplitude of oscillations can be varied by adjusting the current density and magnetic properties. For an optimal oscillation frequency (f{sub opt}), a reduction of the switching time (t{sub 0}) of the free layer is observed. Both f{sub opt} and t{sub 0} increase with the anisotropy field of the free layer.

  8. Spin-orbit torque induced spike-timing dependent plasticity

    SciTech Connect (OSTI)

    Sengupta, Abhronil Al Azim, Zubair; Fong, Xuanyao; Roy, Kaushik

    2015-03-02

    Nanoelectronic devices that mimic the functionality of synapses are a crucial requirement for performing cortical simulations of the brain. In this work, we propose a ferromagnet-heavy metal heterostructure that employs spin-orbit torque to implement spike-timing dependent plasticity. The proposed device offers the advantage of decoupled spike transmission and programming current paths, thereby leading to reliable operation during online learning. Possible arrangement of such devices in a crosspoint architecture can pave the way for ultra-dense neural networks. Simulation studies indicate that the device has the potential of achieving pico-Joule level energy consumption (maximum 2 pJ per synaptic event) which is comparable to the energy consumption for synaptic events in biological synapses.

  9. Low torque hydrodynamic lip geometry for rotary seals

    DOE Patents [OSTI]

    Dietle, Lannie L.; Schroeder, John E.

    2015-07-21

    A hydrodynamically lubricating geometry for the generally circular dynamic sealing lip of rotary seals that are employed to partition a lubricant from an environment. The dynamic sealing lip is provided for establishing compressed sealing engagement with a relatively rotatable surface, and for wedging a film of lubricating fluid into the interface between the dynamic sealing lip and the relatively rotatable surface in response to relative rotation that may occur in the clockwise or the counter-clockwise direction. A wave form incorporating an elongated dimple provides the gradual convergence, efficient impingement angle, and gradual interfacial contact pressure rise that are conducive to efficient hydrodynamic wedging. Skewed elevated contact pressure zones produced by compression edge effects provide for controlled lubricant movement within the dynamic sealing interface between the seal and the relatively rotatable surface, producing enhanced lubrication and low running torque.

  10. WEC-Sim (Wave Energy Converter SIMulator)

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

    ... Social Twitter Google + Vimeo Newsletter Signup SlideShare WEC-Sim (Wave Energy Converter SIMulator) HomeStationary PowerEnergy Conversion EfficiencyWater PowerTechnology ...

  11. Waveguide mode converter and method using same

    DOE Patents [OSTI]

    Moeller, Charles P.

    1990-01-01

    A waveguide mode converter converts electromagnetic power being transmitted in a TE.sub.0n or a TM.sub.0n mode, where n is an integer, to an HE.sub.11 mode. The conversion process occurs in a single stage without requiring the power to pass through any intermediate modes. The converter comprises a length of circular corrugated waveguide formed in a multiperiod periodic curve. The period of the curve is selected to couple the desired modes and decouple undesired modes. The corrugation depth is selected to control the phase propagation constant, or wavenumbers, of the input and output modes, thereby preventing coherent coupling to competing modes. In one embodiment, both the period and amplitude of the curve may be selectively adjusted, thereby allowing the converter to be tuned to maximize the conversion efficiency.

  12. MULTILEVEL CONVERTERS - A NEW BREED OF POWER CONVERTERS Jih-Sheng...

    Office of Scientific and Technical Information (OSTI)

    ... All these converters have been completely analyzed and simulated. Two hardware models have been built and tested to verify the concept. Both simulation and experimental results ...

  13. Electromagnetic analysis of forces and torques on the ITER shield modules due to plasma disruption.

    SciTech Connect (OSTI)

    Kotulski, Joseph Daniel; Coats, Rebecca Sue; Pasik, Michael Francis; Ulrickson, Michael Andrew

    2009-06-01

    An electromagnetic analysis is performed on the ITER shield modules under different plasma disruption scenarios using the OPERA-3d software. The modeling procedure is explained, electromagnetic torques are presented, and results of the modeling are discussed.

  14. Continuum resonance induced electromagnetic torque by a rotating plasma response to static resonant magnetic perturbation field

    SciTech Connect (OSTI)

    Liu Yueqiang; Connor, J. W.; Cowley, S. C.; Ham, C. J.; Hastie, R. J.; Hender, T. C.

    2012-10-15

    A numerical study is carried out, based on a simple toroidal tokamak equilibrium, to demonstrate the radial re-distribution of the electromagnetic torque density, as a result of a rotating resistive plasma (linear) response to a static resonant magnetic perturbation field. The computed electromagnetic torque peaks at several radial locations even in the presence of a single rational surface, due to resonances between the rotating response, in the plasma frame, and both Alfven and sound continuum waves. These peaks tend to merge together to form a rather global torque distribution, when the plasma resistivity is large. The continuum resonance induced net electromagnetic torque remains finite even in the limit of an ideal plasma.

  15. Voltage induced magnetostrictive switching of nanomagnets: Strain assisted strain transfer torque random access memory

    SciTech Connect (OSTI)

    Khan, Asif Nikonov, Dmitri E.; Manipatruni, Sasikanth; Ghani, Tahir; Young, Ian A.

    2014-06-30

    A spintronic device, called the “strain assisted spin transfer torque (STT) random access memory (RAM),” is proposed by combining the magnetostriction effect and the spin transfer torque effect which can result in a dramatic improvement in the energy dissipation relative to a conventional STT-RAM. Magnetization switching in the device which is a piezoelectric-ferromagnetic heterostructure via the combined magnetostriction and STT effect is simulated by solving the Landau-Lifshitz-Gilbert equation incorporating the influence of thermal noise. The simulations show that, in such a device, each of these two mechanisms (magnetostriction and spin transfer torque) provides in a 90° rotation of the magnetization leading a deterministic 180° switching with a critical current significantly smaller than that required for spin torque alone. Such a scheme is an attractive option for writing magnetic RAM cells.

  16. Concentric ring flywheel with hooked ring carbon fiber separator/torque coupler

    DOE Patents [OSTI]

    Kuklo, T.C.

    1999-07-20

    A concentric ring flywheel with expandable separators, which function as torque couplers, between the rings to take up the gap formed between adjacent rings due to differential expansion between different radius rings during rotation of the flywheel. The expandable separators or torque couplers include a hook-like section at an upper end which is positioned over an inner ring and a shelf-like or flange section at a lower end onto which the next adjacent outer ring is positioned. As the concentric rings are rotated the gap formed by the differential expansion there between is partially taken up by the expandable separators or torque couplers to maintain torque and centering attachment of the concentric rings. 2 figs.

  17. Concentric ring flywheel with hooked ring carbon fiber separator/torque coupler

    DOE Patents [OSTI]

    Kuklo, Thomas C.

    1999-01-01

    A concentric ring flywheel with expandable separators, which function as torque couplers, between the rings to take up the gap formed between adjacent rings due to differential expansion between different radius rings during rotation of the flywheel. The expandable separators or torque couplers include a hook-like section at an upper end which is positioned over an inner ring and a shelf-like or flange section at a lower end onto which the next adjacent outer ring is positioned. As the concentric rings are rotated the gap formed by the differential expansion there between is partially taken up by the expandable separators or torque couplers to maintain torque and centering attachment of the concentric rings.

  18. Oscillation characteristics of zero-field spin transfer oscillators with field-like torque

    SciTech Connect (OSTI)

    Guo, Yuan-Yuan; Xue, Hai-Bin; Liu, Zhe-Jie

    2015-05-15

    We theoretically investigate the influence of the field-like spin torque term on the oscillation characteristics of spin transfer oscillators, which are based on MgO magnetic tunnel junctions (MTJs) consisting of a perpendicular magnetized free layer and an in-plane magnetized pinned layer. It is demonstrated that the field-like torque has a strong impact on the steady-state precession current region and the oscillation frequency. In particular, the steady-state precession can occur at zero applied magnetic field when the ratio between the field-like torque and the spin transfer torque takes up a negative value. In addition, the dependence of the oscillation properties on the junction sizes has also been analyzed. The results indicate that this compact structure of spin transfer oscillator without the applied magnetic field is practicable under certain conditions, and it may be a promising configuration for the new generation of on-chip oscillators.

  19. Ultrafast spin exchange-coupling torque via photo-excited charge...

    Office of Scientific and Technical Information (OSTI)

    Title: Ultrafast spin exchange-coupling torque via photo-excited charge-transfer processes In this study, optical control of spin is of central importance in the research of ...

  20. Cogging Torque Reduction in a Permanent Magnet Wind Turbine Generator: Preprint

    SciTech Connect (OSTI)

    Muljadi, E.; Green, J.

    2002-01-01

    In this paper, we investigate three design options to minimize cogging torque: uniformity of air gap, pole width, and skewing. Although the design improvement is intended for small wind turbines, it is also applicable to larger wind turbines.

  1. Method and apparatus for monitoring motor operated valve motor output torque and power at valve seating

    DOE Patents [OSTI]

    Casada, D.A.

    1996-01-16

    A method and apparatus are provided for monitoring a motor operated valve during the brief period when the valve seats and the torque switch trips to deenergize the valve motor. The method uses voltage measurements on the load side of a deenergizing switch that opens to deenergize the motor to determine, among other things, final motor rotational speed and the decelerating torque at motor deenergization. 14 figs.

  2. Method and apparatus for monitoring motor operated valve motor output torque and power at valve seating

    DOE Patents [OSTI]

    Casada, Donald A.

    1996-01-01

    A method and apparatus are provided for monitoring a motor operated valve during the brief period when the valve seats and the torque switch trips to deenergize the valve motor. The method uses voltage measurements on the load side of a deenergizing switch that opens to deenergize the motor to determine, among other things, final motor rotational speed and the decelerating torque at motor deenergization.

  3. Isolated and soft-switched power converter

    DOE Patents [OSTI]

    Peng, Fang Zheng; Adams, Donald Joe

    2002-01-01

    An isolated and soft-switched power converter is used for DC/DC and DC/DC/AC power conversion. The power converter includes two resonant tank circuits coupled back-to-back through an isolation transformer. Each resonant tank circuit includes a pair of resonant capacitors connected in series as a resonant leg, a pair of tank capacitors connected in series as a tank leg, and a pair of switching devices with anti-parallel clamping diodes coupled in series as resonant switches and clamping devices for the resonant leg. The power converter is well suited for DC/DC and DC/DC/AC power conversion applications in which high-voltage isolation, DC to DC voltage boost, bidirectional power flow, and a minimal number of conventional switching components are important design objectives. For example, the power converter is especially well suited to electric vehicle applications and load-side electric generation and storage systems, and other applications in which these objectives are important. The power converter may be used for many different applications, including electric vehicles, hybrid combustion/electric vehicles, fuel-cell powered vehicles with low-voltage starting, remote power sources utilizing low-voltage DC power sources, such as photovoltaics and others, electric power backup systems, and load-side electric storage and generation systems.

  4. Converting energy to medical progress [nuclear medicine] (Technical...

    Office of Scientific and Technical Information (OSTI)

    Converting energy to medical progress nuclear medicine Citation Details In-Document Search Title: Converting energy to medical progress nuclear medicine You are accessing a ...

  5. MHK Technologies/The Crestwing Wave Energy Converter | Open Energy...

    Open Energy Info (EERE)

    Crestwing Wave Energy Converter < MHK Technologies Jump to: navigation, search << Return to the MHK database homepage The Crestwing Wave Energy Converter.jpg Technology Profile...

  6. Hybrid switch for resonant power converters (Patent) | SciTech...

    Office of Scientific and Technical Information (OSTI)

    Patent: Hybrid switch for resonant power converters Citation Details In-Document Search Title: Hybrid switch for resonant power converters A hybrid switch comprising two ...

  7. NNSA Successfully Converts Third Domestic Research Reactor in...

    National Nuclear Security Administration (NNSA)

    Successfully Converts Third Domestic Research Reactor in the Last Year September 13, 2007 ... converted the 1-kilowatt materials test reactor (PUR-1) at Purdue University in Indiana ...

  8. Intrinsic torque reversals induced by magnetic shear effects on the turbulence spectrum in tokamak plasmas

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

    Lu, Z. X.; Wang, W. X.; Diamond, P. H.; Tynan, G.; Ethier, S.; Gao, C.; Rice, J.

    2015-05-04

    We report that intrinsic torque, which can be generated by turbulent stresses, can induce toroidal rotation in a tokamak plasma at rest without direct momentum injection. Reversals in intrinsic torque have been inferred from the observation of toroidal velocity changes in recent lower hybrid current drive (LHCD) experiments. Here we focus on understanding the cause of LHCD-induced intrinsic torque reversal using gyrokinetic simulations and theoretical analyses. A new mechanism for the intrinsic torque reversal linked to magnetic shear (sˆ) effects on the turbulence spectrum is identified. This reversal is a consequence of the ballooning structure at weak sˆ . Basedmore » on realistic profiles from the Alcator C-Mod LHCD experiments, simulations demonstrate that the intrinsic torque reverses for weak sˆ discharges and that the value of sˆ crit is consistent with the experimental results sˆ expcrit [Rice et al., Phys. Rev. Lett. 111, 125003 (2013)]. In conclusion, the consideration of this intrinsic torque feature in our work is important for the understanding of rotation profile generation at weak and its consequent impact on macro-instability stabilization and micro-turbulence reduction, which is crucial for ITER. It is also relevant to internal transport barrier formation at negative or weakly positive sˆ .« less

  9. Perpendicular spin transfer torque magnetic random access memories with high spin torque efficiency and thermal stability for embedded applications (invited)

    SciTech Connect (OSTI)

    Thomas, Luc Jan, Guenole; Zhu, Jian; Liu, Huanlong; Lee, Yuan-Jen; Le, Son; Tong, Ru-Ying; Pi, Keyu; Wang, Yu-Jen; Shen, Dongna; He, Renren; Haq, Jesmin; Teng, Jeffrey; Lam, Vinh; Huang, Kenlin; Zhong, Tom; Torng, Terry; Wang, Po-Kang

    2014-05-07

    Magnetic random access memories based on the spin transfer torque phenomenon (STT-MRAMs) have become one of the leading candidates for next generation memory applications. Among the many attractive features of this technology are its potential for high speed and endurance, read signal margin, low power consumption, scalability, and non-volatility. In this paper, we discuss our recent results on perpendicular STT-MRAM stack designs that show STT efficiency higher than 5?k{sub B}T/?A, energy barriers higher than 100?k{sub B}T at room temperature for sub-40?nm diameter devices, and tunnel magnetoresistance higher than 150%. We use both single device data and results from 8?Mb array to demonstrate data retention sufficient for automotive applications. Moreover, we also demonstrate for the first time thermal stability up to 400?C exceeding the requirement of Si CMOS back-end processing, thus opening the realm of non-volatile embedded memory to STT-MRAM technology.

  10. Saybolt universal viscosity converted to kinematic

    SciTech Connect (OSTI)

    Anaya, C.; Bermudez, O.

    1987-09-21

    This article describes a program for personal and handheld computers, written in Basic, which has been developed for the conversion of Saybolt universal viscosity in Saybolt Universal Seconds (SSU or SUS) to kinematic viscosity in centistokes (cSt), at any selected temperature. It was developed using the mathematical relationship presented in the American Society for Testing and Materials (ASTM) standard D2161-82. In the standard, an equation is presented to convert kinematic viscosity to Saybolt universal viscosity, but nothing is presented to convert from Saybolt to kinematic because it is necessary to find the roots of a nonexplicit function. There are several numerical methods that can be used to determine the roots of the nonexplicit function, and therefore, convert Saybolt universal viscosity to kinematic viscosity. In the program, the first iteration of the second-order Newton-Raphson method is followed by the Wegstein method as a convergence accelerator.

  11. Power system applications for PASC converter systems

    SciTech Connect (OSTI)

    Donnelly, M.K.; Johnson, R.M.

    1994-04-01

    This paper shows, using computer EMTP simulations, some preliminary results of applying pulse amplitude synthesis and control (PASC) technology to single-source level voltage converter system. The method can be applied to any single terminal pair source with appropriate modifications in power extraction interface and computer control program to match source and load impedance characteristics. The PASC realization as discussed here employs banks of transformers, one bank per phase, in which the primaries are connected in parallel through a switch matrix to the dc source. Two opposite polarity primaries per transformer are pulsed alternatively in time to produce an oscillatory sinusoidal output waveform. PASC conversion system capabilities to produce both leading and lagging power factor power output in single-phase and three-phase {Delta} or Y configurations are illustrated. EMTP simulations are used to demonstrate the converter capabilities. Also included are discussions regarding harmonics and potential control strategies to adapt the converter to an application or to minimize harmonics.

  12. WEC-Sim (Wave Energy Converter - SIMulator)

    SciTech Connect (OSTI)

    2014-11-26

    WEC-Sim (Wave Energy Converter SIMulator) is a code developed by Sandia National Laboratories and the National Renewable Energy Laboratory to model wave energy converters (WECs) when they are subject to operational waves. The code is a time-domain modeling tool developed in MATLAB/Simulink using the multi-body dynamics solver SimMechanics. In WEC-Sim, WECs are modeled by connecting rigid bodies to one another with joint or constraint blocks from the WEC-Sim library. WEC-Sim is a publicly available, open-source code to model WECs.

  13. WEC-Sim (Wave Energy Converter - SIMulator)

    Energy Science and Technology Software Center (OSTI)

    2014-11-26

    WEC-Sim (Wave Energy Converter SIMulator) is a code developed by Sandia National Laboratories and the National Renewable Energy Laboratory to model wave energy converters (WECs) when they are subject to operational waves. The code is a time-domain modeling tool developed in MATLAB/Simulink using the multi-body dynamics solver SimMechanics. In WEC-Sim, WECs are modeled by connecting rigid bodies to one another with joint or constraint blocks from the WEC-Sim library. WEC-Sim is a publicly available, open-sourcemore » code to model WECs.« less

  14. Loan Loss Reserve Agreement

    Broader source: Energy.gov [DOE]

    Loan Loss Reserve Agreement, from the Tool Kit Framework: Small Town University Energy Program (STEP).

  15. Performance of Mismatched PV Systems With Submodule Integrated Converters

    SciTech Connect (OSTI)

    Olalla, C; Deline, C; Maksimovic, D

    2014-01-01

    Mismatch power losses in photovoltaic (PV) systems can be reduced by the use of distributed power electronics at the module or submodule level. This paper presents an experimentally validated numerical model that can be used to predict power production with distributed maximum power point tracking (DMPPT) down to the cell level. The model allows the investigations of different DMPPT architectures, as well as the impact of conversion efficiencies and power constraints. Results are presented for annual simulations of three representative partial shading scenarios and two scenarios where mismatches are due to aging over a period of 25 years. It is shown that DMPPT solutions that are based on submodule integrated converters offer 6.9-11.1% improvements in annual energy yield relative to a baseline centralized MPPT scenario.

  16. Utilizing zero-sequence switchings for reversible converters

    DOE Patents [OSTI]

    Hsu, John S.; Su, Gui-Jia; Adams, Donald J.; Nagashima, James M.; Stancu, Constantin; Carlson, Douglas S.; Smith, Gregory S.

    2004-12-14

    A method for providing additional dc inputs or outputs (49, 59) from a dc-to-ac inverter (10) for controlling motor loads (60) comprises deriving zero-sequence components (V.sub.ao, V.sub.bo, and V.sub.co) from the inverter (10) through additional circuit branches with power switching devices (23, 44, 46), transforming the voltage between a high voltage and a low voltage using a transformer or motor (42, 50), converting the low voltage between ac and dc using a rectifier (41, 51) or an H-bridge (61), and providing at least one low voltage dc input or output (49, 59). The transformation of the ac voltage may be either single phase or three phase. Where less than a 100% duty cycle is acceptable, a two-phase modulation of the switching signals controlling the inverter (10) reduces switching losses in the inverter (10). A plurality of circuits for carrying out the invention are also disclosed.

  17. Method of making a catalytic converter

    SciTech Connect (OSTI)

    Bailey, C.H.; De Palma, T.V.; Dillon, J.E.

    1982-08-10

    Arrangement for resiliently mounting a ceramic monolithic type catalytic converter element in a metal housing with a blanket of knit wire mesh material includes at least one circumferential band of high temperature intumescent material containing ceramic fibers positioned within the wire mesh blanket which prevents virtually all bypass leakage around the element and substantially reduces the temperature of the wire mesh.

  18. High-frequency matrix converter with square wave input

    SciTech Connect (OSTI)

    Carr, Joseph Alexander; Balda, Juan Carlos

    2015-03-31

    A device for producing an alternating current output voltage from a high-frequency, square-wave input voltage comprising, high-frequency, square-wave input a matrix converter and a control system. The matrix converter comprises a plurality of electrical switches. The high-frequency input and the matrix converter are electrically connected to each other. The control system is connected to each switch of the matrix converter. The control system is electrically connected to the input of the matrix converter. The control system is configured to operate each electrical switch of the matrix converter converting a high-frequency, square-wave input voltage across the first input port of the matrix converter and the second input port of the matrix converter to an alternating current output voltage at the output of the matrix converter.

  19. Alternative Fuels Data Center: Lancaster Co., Pennsylvania, Converts Trash

    Alternative Fuels and Advanced Vehicles Data Center [Office of Energy Efficiency and Renewable Energy (EERE)]

    to Energy Lancaster Co., Pennsylvania, Converts Trash to Energy to someone by E-mail Share Alternative Fuels Data Center: Lancaster Co., Pennsylvania, Converts Trash to Energy on Facebook Tweet about Alternative Fuels Data Center: Lancaster Co., Pennsylvania, Converts Trash to Energy on Twitter Bookmark Alternative Fuels Data Center: Lancaster Co., Pennsylvania, Converts Trash to Energy on Google Bookmark Alternative Fuels Data Center: Lancaster Co., Pennsylvania, Converts Trash to Energy on

  20. Alternative Fuels Data Center: Landfills Convert Biogas Into Renewable

    Alternative Fuels and Advanced Vehicles Data Center [Office of Energy Efficiency and Renewable Energy (EERE)]

    Natural Gas Landfills Convert Biogas Into Renewable Natural Gas to someone by E-mail Share Alternative Fuels Data Center: Landfills Convert Biogas Into Renewable Natural Gas on Facebook Tweet about Alternative Fuels Data Center: Landfills Convert Biogas Into Renewable Natural Gas on Twitter Bookmark Alternative Fuels Data Center: Landfills Convert Biogas Into Renewable Natural Gas on Google Bookmark Alternative Fuels Data Center: Landfills Convert Biogas Into Renewable Natural Gas on

  1. Alternative Fuels Data Center: Veolia Transportation Converts Taxi Fleet to

    Alternative Fuels and Advanced Vehicles Data Center [Office of Energy Efficiency and Renewable Energy (EERE)]

    Propane Veolia Transportation Converts Taxi Fleet to Propane to someone by E-mail Share Alternative Fuels Data Center: Veolia Transportation Converts Taxi Fleet to Propane on Facebook Tweet about Alternative Fuels Data Center: Veolia Transportation Converts Taxi Fleet to Propane on Twitter Bookmark Alternative Fuels Data Center: Veolia Transportation Converts Taxi Fleet to Propane on Google Bookmark Alternative Fuels Data Center: Veolia Transportation Converts Taxi Fleet to Propane on

  2. SATURATED TORQUE FORMULA FOR PLANETARY MIGRATION IN VISCOUS DISKS WITH THERMAL DIFFUSION: RECIPE FOR PROTOPLANET POPULATION SYNTHESIS

    SciTech Connect (OSTI)

    Masset, F. S. [Instituto de Ciencias Fisicas, Universidad Nacional Autonoma de Mexico (UNAM), Apdo. Postal 48-3, 62251-Cuernavaca, Morelos (Mexico); Casoli, J., E-mail: masset@fis.unam.m, E-mail: jules.casoli@cea.f, E-mail: masset@fis.unam.m [Laboratoire AIM, CEA/DSM, CNRS, Universite Paris Diderot, Irfu/Service d'Astrophysique, Bat. 709, CEA/Saclay, 91191 Gif-sur-Yvette (France)

    2010-11-10

    We provide torque formulae for low-mass planets undergoing type I migration in gaseous disks. These torque formulae put special emphasis on the horseshoe drag, which is prone to saturation: the asymptotic value reached by the horseshoe drag depends on a balance between coorbital dynamics (which tends to cancel out or saturate the torque) and diffusive processes (which tend to restore the unperturbed disk profiles, thereby desaturating the torque). We entertain the question of this asymptotic value and derive torque formulae that give the total torque as a function of the disk's viscosity and thermal diffusivity. The horseshoe drag features two components: one that scales with the vortensity gradient and another that scales with the entropy gradient and constitutes the most promising candidate for halting inward type I migration. Our analysis, which is complemented by numerical simulations, recovers characteristics already noted by numericists, namely, that the viscous timescale across the horseshoe region must be shorter than the libration time in order to avoid saturation and that, provided this condition is satisfied, the entropy-related part of the horseshoe drag remains large if the thermal timescale is shorter than the libration time. Side results include a study of the Lindblad torque as a function of thermal diffusivity and a contribution to the corotation torque arising from vortensity viscously created at the contact discontinuities that appear at the horseshoe separatrices. For the convenience of the reader mostly interested in the torque formulae, Section 8 is self-contained.

  3. MULTILEVEL CONVERTERS - A NEW BREED OF POWER CONVERTERS Jih-Sheng...

    Office of Scientific and Technical Information (OSTI)

    ... a power converter needs to transfer real power from ac to dc (rectifier) or dc to ac (inverter operation). When operating at unity power factor, the charging time for ...

  4. Optical analog-to-digital converter

    DOE Patents [OSTI]

    Vawter, G. Allen; Raring, James; Skogen, Erik J.

    2009-07-21

    An optical analog-to-digital converter (ADC) is disclosed which converts an input optical analog signal to an output optical digital signal at a sampling rate defined by a sampling optical signal. Each bit of the digital representation is separately determined using an optical waveguide interferometer and an optical thresholding element. The interferometer uses the optical analog signal and the sampling optical signal to generate a sinusoidally-varying output signal using cross-phase-modulation (XPM) or a photocurrent generated from the optical analog signal. The sinusoidally-varying output signal is then digitized by the thresholding element, which includes a saturable absorber or at least one semiconductor optical amplifier, to form the optical digital signal which can be output either in parallel or serially.

  5. Thyristor converter for capacitive laser accumulators

    SciTech Connect (OSTI)

    Benediktov, G.L.

    1983-12-01

    Theoretical and experimental investigations showed the possibility of construction of a thyristor converter for power supply of capacitive accumulators of gas-discharge lamps for a laser with provision for constancy of power consumed from the power source. The curves given for the law of change of energy depending on voltage on the accumulator capacitance and the expressions for current and voltage in the charging circuit make it possible to make an engineer calculation of the circuit of the thyristor converter. The proposed method of calculating the process of charging of a capacitive accumulator can be used for the calculation of a circuit, providing other laws of change of power in time which differ from the law P const.

  6. Converting DYNAMO simulations to Powersim Studio simulations

    SciTech Connect (OSTI)

    Walker, La Tonya Nicole; Malczynski, Leonard A.

    2014-02-01

    DYNAMO is a computer program for building and running 'continuous' simulation models. It was developed by the Industrial Dynamics Group at the Massachusetts Institute of Technology for simulating dynamic feedback models of business, economic, and social systems. The history of the system dynamics method since 1957 includes many classic models built in DYANMO. It was not until the late 1980s that software was built to take advantage of the rise of personal computers and graphical user interfaces that DYNAMO was supplanted. There is much learning and insight to be gained from examining the DYANMO models and their accompanying research papers. We believe that it is a worthwhile exercise to convert DYNAMO models to more recent software packages. We have made an attempt to make it easier to turn these models into a more current system dynamics software language, Powersim Studio produced by Powersim AS2 of Bergen, Norway. This guide shows how to convert DYNAMO syntax into Studio syntax.

  7. Component technology for Stirling power converters

    SciTech Connect (OSTI)

    Thieme, L.G.

    1994-09-01

    NASA Lewis Research Center has organized a component technology program as part of the efforts to develop Stirling converter technology for space power applications. The Stirling space power program is part of the NASA High Capacity Power Project of the Civil Space Technology Initiative (CSTI). NASA Lewis is also providing technical management for a DOE/Sandia program to develop Stirling converters for solar terrestrial power producing electricity for the utility grid. The primary contractors for the space power and solar terrestrial programs develop component technologies directly related to their program goals. This Lewis component technology effort, while coordinated with the main programs, aims at longer term issues, advanced technologies, and independent assessments. This paper will present an overview of work on linear alternators, engine/alternator/load interactions and controls, heat exchangers, materials, life and reliability, and bearings.

  8. convert program | National Nuclear Security Administration

    National Nuclear Security Administration (NNSA)

    convert program Material Management and Minimization The Office of Material Management and Minimization (M3) presents an integrated approach to addressing the persistent threat posed by nuclear materials through a full cycle of materials management and minimization efforts. Consistent with the President's highly enriched uranium (HEU) and... Conversion A key starting point for material management and minimization is reducing the civilian use of and demands for weapon-grade nuclear material. The

  9. APPARATUS FOR CONVERTING HEAT INTO ELECTRICITY

    DOE Patents [OSTI]

    Crouthamel, C.E.; Foster, M.S.

    1964-01-28

    This patent shows an apparatus for converting heat to electricity. It includes a galvanic cell having an anodic metal anode, a fused salt electrolyte, and a hydrogen cathode having a diffusible metal barrier of silver-- palladium alloy covered with sputtered iron on the side next to the fused electrolyte. Also shown is a regenerator for regenerating metal hydride produced by the galvanic cell into hydrogen gas and anodic metal, both of which are recycled. (AEC)

  10. Coastal land loss in Texas - An overview

    SciTech Connect (OSTI)

    Morton, R.A.; Paine, J.G. )

    1990-09-01

    Each year in Texas more than 1,500 acres of prime real estate and productive wetlands are destroyed along the Gulf shoreline and near the bay margins primarily as a result of coastal erosion and submergence. Wetland losses constitute about half of the total land losses. Historical analyses of maps and aerial photographs since the mid-1800s indicate that land losses are accelerating and that human activities are either directly or indirectly responsible for the increased losses, Natural decreases in sediment supply since the modern sea-level stillstand have been exacerbated by (1) river basin projects that reduce the volume of sediment transported to the coast and (2) coastal structures and navigation projects that prevent redistribution of littoral sediments along the coast. Erosion is primarily caused by high wave and current energy combined with an inadequate supply of sediment. Erosion is responsible for higher local rates of land loss than submergence, and the erosion losses are more perceptible, especially after major storms when the greatest losses occur. The principal components of submergence are subsidence and the eustatic rise in sea level. Together these components are recorded by tide gauges as a relative rise in sea level. Submergence converts uplands to wetlands and wetlands to open water. These surficial changes occur mostly on the coastal plain but are also observed on barrier islands and bayhead deltas and within entrenched valleys. Although compactional subsidence is a natural process operating in the Gulf Coast basin, most of the accelerated land-surface subsidence in Texas is attributed to extraction of shallow ground water or production of hydrocarbons at moderate depths. Faults activated by the withdrawal of these fluids concentrate the subsidence near the fault planes. Coastal land losses caused by dredging are less than those caused by erosion and submergence, but they constitute a growing percentage of total land losses.

  11. Research update: Spin transfer torques in permalloy on monolayer MoS2

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

    Zhang, Wei; Sklenar, Joseph; Hsu, Bo; Jiang, Wanjun; Jungfleisch, Matthias B.; Xiao, Jiao; Fradin, Frank Y.; Liu, Yaohua; Pearson, John E.; Ketterson, John B.; et al

    2016-03-03

    We observe current induced spin transfertorque resonance in permalloy (Py) grown on monolayer MoS2. By passing rf current through the Py/MoS2 bilayer, field-like and damping-like torques are induced which excite the ferromagnetic resonance of Py. The signals are detected via a homodyne voltage from anisotropic magnetoresistance of Py. In comparison to other bilayer systems with strong spin-orbit torques, the monolayer MoS2 cannot provide bulk spin Hall effects and thus indicates the purely interfacial nature of the spin transfer torques. Furthermore, our results indicate the potential of two-dimensional transition-metal dichalcogenide for the use of interfacial spin-orbitronics applications.

  12. Large voltage-induced modification of spin-orbit torques in Pt/Co/GdOx

    SciTech Connect (OSTI)

    Emori, Satoru Bauer, Uwe; Woo, Seonghoon; Beach, Geoffrey S. D.

    2014-12-01

    We report on large modifications of current-induced spin-orbit torques in a gated Pt/Co/Gd-oxide microstrip due to voltage-driven O{sup 2−} migration. The Slonczewski-like and field-like torques are quantified using a low-frequency harmonic technique based on the polar magneto-optical Kerr effect. Voltage-induced oxidation of Co enhances the Slonczewski-like torque by as much as an order of magnitude and simultaneously reduces the anisotropy energy barrier by a factor of ∼5. Such magneto-ionic tuning of interfacial spin-orbit effects may significantly enhance the efficiency of magnetization switching and provide additional degrees of freedom in spintronic devices.

  13. Thermally activated switching of perpendicular magnet by spin-orbit spin torque

    SciTech Connect (OSTI)

    Lee, Ki-Seung; Lee, Seo-Won; Min, Byoung-Chul; Lee, Kyung-Jin

    2014-02-17

    We theoretically investigate the threshold current for thermally activated switching of a perpendicular magnet by spin-orbit spin torque. Based on the Fokker-Planck equation, we obtain an analytic expression of the switching current, in agreement with numerical result. We find that thermal energy barrier exhibits a quasi-linear dependence on the current, resulting in an almost linear dependence of switching current on the log-scaled current pulse-width even below 10 ns. This is in stark contrast to standard spin torque switching, where thermal energy barrier has a quadratic dependence on the current and the switching current rapidly increases at short pulses. Our results will serve as a guideline to design and interpret switching experiments based on spin-orbit spin torque.

  14. Zero field high frequency oscillations in dual free layer spin torque oscillators

    SciTech Connect (OSTI)

    Braganca, P. M. Pi, K.; Zakai, R.; Childress, J. R.; Gurney, B. A.

    2013-12-02

    We observe microwave oscillations in relatively simple spin valve spin torque oscillators consisting of two in-plane free layers without spin polarizing layers. These devices exhibit two distinct modes which can reach frequencies >25?GHz in the absence of an applied magnetic field. Macrospin simulations identify these two modes as optical and acoustic modes excited by the coupling of the two layers through dipole field and spin torque effects. These results demonstrate the potential of this system as a large output power, ultrahigh frequency signal generator that can operate without magnetic field.

  15. Local spin torque induced by electron electric dipole moment in the YbF molecule

    SciTech Connect (OSTI)

    Fukuda, Masahiro; Senami, Masato; Ogiso, Yoji; Tachibana, Akitomo

    2014-10-06

    In this study, we show the modification of the equation of motion of the electronic spin, which is derived by the quantum electron spin vorticity principle, by the effect of the electron electric dipole moment (EDM). To investigate the new contribution to spin torque by EDM, using first principle calculations, we visualize distributions of the local spin angular momentum density and local spin torque density of the YbF molecule on which the static electric field and magnetic field are applied at t = 0.

  16. Numerical analysis of thermally assisted spin-transfer torque magnetization reversal in synthetic ferrimagnetic free layers

    SciTech Connect (OSTI)

    Shen, J.; Shi, M.; Tanaka, T. Matsuyama, K.

    2015-05-07

    The spin transfer torque magnetization reversal of synthetic ferrimagnetic free layers under pulsed temperature rise was numerically studied by solving the LandauLifshitzGilbert equation, taking into account the stochastic random fields, the temperature dependence of magnetic parameters, and the spin torque terms. The anti-parallel magnetization configuration was retained at the elevated temperature, due to interlayer dipole coupling. A significant thermal assistance effect, resulting in a 40% reduction in the switching current, was demonstrated during a nanosecond pulsed temperature rise up to 77% of the Curie temperature.

  17. One Man's Trash, Another Man's Fuel: BMW Plant Converts Landfill...

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

    One Man's Trash, Another Man's Fuel: BMW Plant Converts Landfill Gas to Hydrogen Fuel One Man's Trash, Another Man's Fuel: BMW Plant Converts Landfill Gas to Hydrogen Fuel August ...

  18. Research Reactor at University of Florida Has Been Converted...

    National Nuclear Security Administration (NNSA)

    Research Reactor at University of Florida Has Been Converted October 18, 2006 By End of ... has successfully converted a research reactor at the University of Florida from the use ...

  19. Idaho Application for Permit to Convert a Geothermal Injection...

    Open Energy Info (EERE)

    Convert a Geothermal Injection Well - Form 4003-3 Jump to: navigation, search OpenEI Reference LibraryAdd to library Form: Idaho Application for Permit to Convert a Geothermal...

  20. DOE Announces Webinars on the Wave Energy Converter Prize, the...

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

    the Wave Energy Converter Prize, the Best of the Clean Cities Tools and Resources, and More DOE Announces Webinars on the Wave Energy Converter Prize, the Best of the Clean Cities...

  1. Heat Pump Water Heater using Solid-State Energy Converters |...

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

    Water Heater using Solid-State Energy Converters Heat Pump Water Heater using Solid-State Energy Converters Sheetak will work on developing a full scale prototype of its low cost ...

  2. Voltage balanced multilevel voltage source converter system

    DOE Patents [OSTI]

    Peng, F.Z.; Lai, J.S.

    1997-07-01

    Disclosed is a voltage balanced multilevel converter for high power AC applications such as adjustable speed motor drives and back-to-back DC intertie of adjacent power systems. This converter provides a multilevel rectifier, a multilevel inverter, and a DC link between the rectifier and the inverter allowing voltage balancing between each of the voltage levels within the multilevel converter. The rectifier is equipped with at least one phase leg and a source input node for each of the phases. The rectifier is further equipped with a plurality of rectifier DC output nodes. The inverter is equipped with at least one phase leg and a load output node for each of the phases. The inverter is further equipped with a plurality of inverter DC input nodes. The DC link is equipped with a plurality of rectifier charging means and a plurality of inverter discharging means. The plurality of rectifier charging means are connected in series with one of the rectifier charging means disposed between and connected in an operable relationship with each adjacent pair of rectifier DC output nodes. The plurality of inverter discharging means are connected in series with one of the inverter discharging means disposed between and connected in an operable relationship with each adjacent pair of inverter DC input nodes. Each of said rectifier DC output nodes are individually electrically connected to the respective inverter DC input nodes. By this means, each of the rectifier DC output nodes and each of the inverter DC input nodes are voltage balanced by the respective charging and discharging of the rectifier charging means and the inverter discharging means. 15 figs.

  3. Voltage balanced multilevel voltage source converter system

    DOE Patents [OSTI]

    Peng, Fang Zheng; Lai, Jih-Sheng

    1997-01-01

    A voltage balanced multilevel converter for high power AC applications such as adjustable speed motor drives and back-to-back DC intertie of adjacent power systems. This converter provides a multilevel rectifier, a multilevel inverter, and a DC link between the rectifier and the inverter allowing voltage balancing between each of the voltage levels within the multilevel converter. The rectifier is equipped with at least one phase leg and a source input node for each of the phases. The rectifier is further equipped with a plurality of rectifier DC output nodes. The inverter is equipped with at least one phase leg and a load output node for each of the phases. The inverter is further equipped with a plurality of inverter DC input nodes. The DC link is equipped with a plurality of rectifier charging means and a plurality of inverter discharging means. The plurality of rectifier charging means are connected in series with one of the rectifier charging means disposed between and connected in an operable relationship with each adjacent pair of rectifier DC output nodes. The plurality of inverter discharging means are connected in series with one of the inverter discharging means disposed between and connected in an operable relationship with each adjacent pair of inverter DC input nodes. Each of said rectifier DC output nodes are individually electrically connected to the respective inverter DC input nodes. By this means, each of the rectifier DC output nodes and each of the inverter DC input nodes are voltage balanced by the respective charging and discharging of the rectifier charging means and the inverter discharging means.

  4. Solid state transport-based thermoelectric converter

    DOE Patents [OSTI]

    Hu, Zhiyu

    2010-04-13

    A solid state thermoelectric converter includes a thermally insulating separator layer, a semiconducting collector and an electron emitter. The electron emitter comprises a metal nanoparticle layer or plurality of metal nanocatalyst particles disposed on one side of said separator layer. A first electrically conductive lead is electrically coupled to the electron emitter. The collector layer is disposed on the other side of the separator layer, wherein the thickness of the separator layer is less than 1 .mu.m. A second conductive lead is electrically coupled to the collector layer.

  5. Converting urban tree maintenance residue to energy

    SciTech Connect (OSTI)

    Murphey, W.K.; Massey, J.G.; Sumrall, A.

    1980-01-01

    Three methods of utilizing urban wood waste collected by a tree maintenance firm in Houston, Texas (handling 30,000 ton waste/year) are examined: (a) hauling to a remote landfill; (b) chipping and hauling to a (local) power plant and converting to electricity; and (c) chipping and selling to an outside firm for use as boiler fuel. Breakdown of costs are given for each method in monetary and energy terms. Method (b) was the cheapest, producing a net energy gain (870 million Btu/day), but the firm chose method (c), since it realized a direct monetary return.

  6. survival analysis of wave energy converters

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

    supplemental directives Supplemental Directives NA-1 SD 226.1-1A Headquarters Biennial Review of Nuclear Safety Performance December 16, 2011 NNSA SD 226.1B NNSA Site Governance August 12, 2016 NNSA SD 243.1 Admin Change 1 Records Management Program March 21, 2016 NA SD 251.1 NNSA Policies, Supplemental Directives, and Business Operating

    survival analysis of wave energy converters - Sandia Energy Energy Search Icon Sandia Home Locations Contact Us Employee Locator Energy & Climate Secure

  7. Alternative Fuels Data Center: City of Hendersonville Converts Vehicles to

    Alternative Fuels and Advanced Vehicles Data Center [Office of Energy Efficiency and Renewable Energy (EERE)]

    Natural Gas in North Carolina City of Hendersonville Converts Vehicles to Natural Gas in North Carolina to someone by E-mail Share Alternative Fuels Data Center: City of Hendersonville Converts Vehicles to Natural Gas in North Carolina on Facebook Tweet about Alternative Fuels Data Center: City of Hendersonville Converts Vehicles to Natural Gas in North Carolina on Twitter Bookmark Alternative Fuels Data Center: City of Hendersonville Converts Vehicles to Natural Gas in North Carolina on

  8. CEBAF beam loss accounting

    SciTech Connect (OSTI)

    Ursic, R.; Mahoney, K.; Hovater, C.; Hutton, A.; Sinclair, C.

    1995-12-31

    This paper describes the design and implementation of a beam loss accounting system for the CEBAF electron accelerator. This system samples the beam curent throughout the beam path and measures the beam current accurately. Personnel Safety and Machine Protection systems use this system to turn off the beam when hazardous beam losses occur.

  9. Mechanical vibration to electrical energy converter

    DOE Patents [OSTI]

    Kellogg, Rick Allen; Brotz, Jay Kristoffer

    2009-03-03

    Electromechanical devices that generate an electrical signal in response to an external source of mechanical vibrations can operate as a sensor of vibrations and as an energy harvester for converting mechanical vibration to electrical energy. The devices incorporate a magnet that is movable through a gap in a ferromagnetic circuit, wherein a coil is wound around a portion of the ferromagnetic circuit. A flexible coupling is used to attach the magnet to a frame for providing alignment of the magnet as it moves or oscillates through the gap in the ferromagnetic circuit. The motion of the magnet can be constrained to occur within a substantially linear range of magnetostatic force that develops due to the motion of the magnet. The devices can have ferromagnetic circuits with multiple arms, an array of magnets having alternating polarity and, encompass micro-electromechanical (MEM) devices.

  10. Modular Power Converters for PV Applications

    SciTech Connect (OSTI)

    Ozpineci, Burak; Tolbert, Leon M

    2012-05-01

    This report describes technical opportunities to serve as parts of a technological roadmap for Shoals Technologies Group in power electronics for PV applications. There are many different power converter circuits that can be used for solar inverter applications. The present applications do not take advantage of the potential for using common modules. We envision that the development of a power electronics module could enable higher reliability by being durable and flexible. Modules would have fault current limiting features and detection circuits such that they can limit the current through the module from external faults and can identify and isolate internal faults such that the remaining modules can continue to operate with only minimal disturbance to the utility or customer. Development of a reliable, efficient, low-cost, power electronics module will be a key enabling technology for harnessing more power from solar panels and enable plug and play operation. Power electronics for computer power supplies, communication equipment, and transportation have all targeted reliability and modularity as key requirements and have begun concerted efforts to replace monolithic components with collections of common smart modules. This is happening on several levels including (1) device level with intelligent control, (2) functional module level, and (3) system module. This same effort is needed in power electronics for solar applications. Development of modular units will result in standard power electronic converters that will have a lower installed and operating cost for the overall system. These units will lead to increased adaptability and flexibility of solar inverters. Incorporating autonomous fault current limiting and reconfiguration capabilities into the modules and having redundant modules will lead to a durable converter that can withstand the rigors of solar power generation for more than 30 years. Our vision for the technology roadmap is that there is no need

  11. Catalytic converter for automotive exhaust system

    SciTech Connect (OSTI)

    Merry, R.P.

    1986-10-14

    This patent describes a catalytic converter having a metallic casing, a unitary, solid ceramic catalytic element disposed within the casing, and resilient means disposed between the catalytic element and the metallic casing for positioning the catalytic element and for absorbing mechanical and thermal shock. The improvement described here comprises: the resilient means being a flexible intumescent planar sheet corrugated with a generally sinusoidal wave pattern along both its lengthwise edges. The corrugations are generally parallel and regular and are comprised of substantially equal ridges and hollows having a perimeter to frequency ratio in a range of 2.44 to 4.88 and amplitude in a range of 12 to 50% of the width of the sheet.

  12. Detrimental effect of interfacial Dzyaloshinskii-Moriya interaction on perpendicular spin-transfer-torque magnetic random access memory

    SciTech Connect (OSTI)

    Jang, Peong-Hwa; Lee, Seo-Won E-mail: kj-lee@korea.ac.kr; Song, Kyungmi; Lee, Seung-Jae; Lee, Kyung-Jin E-mail: kj-lee@korea.ac.kr

    2015-11-16

    Interfacial Dzyaloshinskii-Moriya interaction in ferromagnet/heavy metal bilayers is recently of considerable interest as it offers an efficient control of domain walls and the stabilization of magnetic skyrmions. However, its effect on the performance of perpendicular spin transfer torque memory has not been explored yet. We show based on numerical studies that the interfacial Dzyaloshinskii-Moriya interaction decreases the thermal energy barrier while increases the switching current. As high thermal energy barrier as well as low switching current is required for the commercialization of spin torque memory, our results suggest that the interfacial Dzyaloshinskii-Moriya interaction should be minimized for spin torque memory applications.

  13. Integrated Solar Power Converters: Wafer-Level Sub-Module Integrated DC/DC Converter

    SciTech Connect (OSTI)

    2012-02-09

    Solar ADEPT Project: CU-Boulder is developing advanced power conversion components that can be integrated into individual solar panels to improve energy yields. The solar energy that is absorbed and collected by a solar panel is converted into useable energy for the grid through an electronic component called an inverter. Many large, conventional solar energy systems use one, central inverter to convert energy. CU-Boulder is integrating smaller, microinverters into individual solar panels to improve the efficiency of energy collection. The University’s microinverters rely on electrical components that direct energy at high speeds and ensure that minimal energy is lost during the conversion process—improving the overall efficiency of the power conversion process. CU-Boulder is designing its power conversion devices for use on any type of solar panel.

  14. An integrated flyback converter for DC uninterruptible power supply

    SciTech Connect (OSTI)

    Ma, K.W.; Lee, Y.S.

    1996-03-01

    An integrated flyback converter performing the combined functions of uninterruptible power supply (UPS) and switch-mode power supply (SMPS) is presented. This converter has a high voltage main power input and a low voltage backup battery input. DC output is obtained form the main input via a flyback converter during normal operation and from the backup battery via another flyback converter when input power fails. High conversion efficiency is achieved in normal, backup, and charging modes as there is only a single dc-dc conversion in each mode. The converter circuit is very simple, with two switching transistors, a relay for mode switching, and a single magnetic structure only. This new design offers substantial improvement in efficiency, size, and cost over the conventional cascade of UPS and SMPS due to single voltage conversion, high frequency switching, and removal of design redundancy. The operation, design, analysis, and experimental results of the converter are presented.

  15. Current dependence of spin torque switching rate based on Fokker-Planck approach

    SciTech Connect (OSTI)

    Taniguchi, Tomohiro Imamura, Hiroshi

    2014-05-07

    The spin torque switching rate of an in-plane magnetized system in the presence of an applied field is derived by solving the Fokker-Planck equation. It is found that three scaling currents are necessary to describe the current dependence of the switching rate in the low-current limit. The dependences of these scaling currents on the applied field strength are also studied.

  16. Method and system for determining the torque required to launch a vehicle having a hybrid drive-train

    DOE Patents [OSTI]

    Hughes, Douglas A.

    2006-04-04

    A method and system are provided for determining the torque required to launch a vehicle having a hybrid drive-train that includes at least two independently operable prime movers. The method includes the steps of determining the value of at least one control parameter indicative of a vehicle operating condition, determining the torque required to launch the vehicle from the at least one determined control parameter, comparing the torque available from the prime movers to the torque required to launch the vehicle, and controlling operation of the prime movers to launch the vehicle in response to the comparing step. The system of the present invention includes a control unit configured to perform the steps of the method outlined above.

  17. Converter Topologies for Wired and Wireless Battery Chargers | Department

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

    of Energy Converter Topologies for Wired and Wireless Battery Chargers Converter Topologies for Wired and Wireless Battery Chargers 2011 DOE Hydrogen and Fuel Cells Program, and Vehicle Technologies Program Annual Merit Review and Peer Evaluation ape033_su_2011_o.pdf (384.8 KB) More Documents & Publications Converter Topologies for Wired and Wireless Battery Chargers Inverter Using Current Source Topology Wireless Plug-in Electric Vehicle (PEV) Charging

  18. Process for Converting Algal Oil to Alternative Aviation Fuel - Energy

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

    Innovation Portal Process for Converting Algal Oil to Alternative Aviation Fuel Los Alamos National Laboratory Contact LANL About This Technology The conversion process uses a Kolbe-based method of converting the fatty acids from the algal lipid triglycerides to fuel. The conversion process uses a Kolbe-based method of converting the fatty acids from the algal lipid triglycerides to fuel. Technology Marketing Summary Conversion of triglyceride oils extracted from algae-derived lipids into

  19. Dynamic Simulation of Shipping Package Subjected to Torque Load and Sequential Impacts

    SciTech Connect (OSTI)

    Wu, T

    2006-04-17

    A numerical technique has been developed to simulate the structural responses of radioactive material packaging components requiring closure-tightening torque to the scenarios of the hypothetical accident conditions (HAC) defined in the Code of Federal Regulations Title 10 part 71 (10CFR 71). A rigorous solution to this type of problem poses a considerable mathematical challenge. Conventional methods for evaluating the residue stresses due to the torque load are either inaccurate or not applicable to dynamic analyses. In addition, the HAC events occur sequentially and the cumulative damage to the package needs to be evaluated. Commonly, individual HAC events are analyzed separately and the cumulative damage is not addressed. As a result, strict compliance of the package with the requirements specified in 10CFR 71 is usually demonstrated by physical testing. The proposed technique utilizes the combination of kinematic constraints, rigid-body motions and structural deformations to overcome some of the difficulties encountered in modeling the effect of cumulative damage in numerical solutions. The analyses demonstrating use of this technique were performed to determine the cumulative damage of torque preload, a 30-foot drop, a 30-foot dynamic crush and a 40-inch free fall onto a mild steel pipe.

  20. Sandia National Laboratories Uses Its Wave Energy Converter ...

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

    Uses Its Wave Energy Converter (WEC) to Harness the Motion of the Ocean - Sandia Energy ... Secure & Sustainable Energy Future Stationary Power Energy Conversion Efficiency Solar ...

  1. WEC-Sim (Wave Energy Converter SIMulator) Code Development and...

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

    (Wave Energy Converter SIMulator) Code Development and Training Class - Sandia Energy ... Secure & Sustainable Energy Future Stationary Power Energy Conversion Efficiency Solar ...

  2. Sandia, NREL Release Wave Energy Converter Modeling and Simulation...

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

    NREL Release Wave Energy Converter Modeling and Simulation Code: WEC-Sim - Sandia Energy ... Secure & Sustainable Energy Future Stationary Power Energy Conversion Efficiency Solar ...

  3. MHK Technologies/WAVE ENERGY CONVERTER | Open Energy Information

    Open Energy Info (EERE)

    WAVE ENERGY CONVERTER < MHK Technologies Jump to: navigation, search << Return to the MHK database homepage Technology Profile Technology Resource Click here Wave Technology Type...

  4. MHK Technologies/Magnetohydrodynamic MHD Wave Energy Converter...

    Open Energy Info (EERE)

    Magnetohydrodynamic MHD Wave Energy Converter MWEC < MHK Technologies Jump to: navigation, search << Return to the MHK database homepage Magnetohydrodynamic MHD Wave Energy...

  5. Multilevel Converters for Power System Applications J. S. Lai...

    Office of Scientific and Technical Information (OSTI)

    ... All these converters have been completely analyzed and simulated. One hardware model has been built and tested to verify the concept. Both simulation and experimental results prove ...

  6. NREL: Wind Power Research - NREL Research Helps Convert Overabundant...

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

    NREL Research Helps Convert Overabundant Methane into Useful Products March 18, 2016 Photo of a fermentation vessel cultivating our bacteria to produce lactic acid. Using ...

  7. Wave Energy Converter System Requirements and Performance Metrics

    Broader source: Energy.gov [DOE]

    The Energy Department and Wave Energy Scotland are holding a joint workshop on wave energy converter (WEC) system requirements and performance metrics on Friday, February 26.

  8. Wave Energy Converter Effects on Nearshore Wave Propagation

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

    Energy Converter Effects on Nearshore Wave Propagation Jesse Roberts 1 , Grace Chang *2 , Craig Jones *3 Sandia National Laboratories 1515 Eubank SE, Albuquerque, NM 87123 USA 1...

  9. MHK Technologies/Multi Absorbing Wave Energy Converter MAWEC...

    Open Energy Info (EERE)

    Wave Surge Converter Technology Readiness Level Click here TRL 1-3: Discovery Concept Definition Early Stage Development & Design & Engineering Technology Description MAWEC...

  10. MHK Technologies/OCEANTEC Wave Energy Converter | Open Energy...

    Open Energy Info (EERE)

    Energy Converter.jpg Technology Profile Primary Organization OCEANTEC Energias Marinas S L Technology Resource Click here Wave Technology Type Click here Attenuator Technology...

  11. Sandia Energy - Advanced Controls of Wave Energy Converters May...

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

    Advanced Controls of Wave Energy Converters May Increase Power Capture Up to 330% Home Renewable Energy Energy Water Power Partnership News News & Events Computational Modeling &...

  12. Heat Pump Water Heater Using Solid-State Energy Converters

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

    Heat Pump Water Heater Using Solid-State Energy Converters 2016 Building Technologies ... Project Goal: Demonstrate a home water heater product with affordable and reliable ...

  13. Heat Pump Water Heater Using Solid-State Energy Converters

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

    Heat Pump Water Heater Using Solid-State Energy Converters 2015 Building Technologies ... Home Water Heaters with Affordable, Reliable Solid-State Heat Pumps Key Partners: ...

  14. Method and apparatus for effecting light-off of a catalytic converter in a hybrid powertrain system

    DOE Patents [OSTI]

    Roos, Bryan Nathaniel; Spohn, Brian L

    2013-07-02

    A powertrain system includes a hybrid transmission and an internal combustion engine coupled to an exhaust aftertreatment device. A method for operating the powertrain system includes operating the hybrid transmission to generate tractive torque responsive to an operator torque request with the internal combustion engine in an engine-off state so long as the tractive torque is less than a threshold. The internal combustion engine is operated in an engine-on state at preferred operating conditions to effect light-off of the exhaust aftertreatment device and the hybrid transmission is coincidentally operated to generate tractive torque responsive to the operator torque request when the operator torque request exceeds the threshold. The internal combustion engine is then operated in the engine-on state to generate tractive torque responsive to the operator torque request.

  15. Magnet Technology for Power Converters: Nanocomposite Magnet Technology for High Frequency MW-Scale Power Converters

    SciTech Connect (OSTI)

    2012-02-27

    Solar ADEPT Project: CMU is developing a new nanoscale magnetic material that will reduce the size, weight, and cost of utility-scale PV solar power conversion systems that connect directly to the grid. Power converters are required to turn the energy that solar power systems create into useable energy for the grid. The power conversion systems made with CMUs nanoscale magnetic material have the potential to be 150 times lighter and significantly smaller than conventional power conversion systems that produce similar amounts of power.

  16. Optimal Driving Force for Converting Excitons into Free Carriers in Excitonic Solar Cells

    SciTech Connect (OSTI)

    Coffey, D. C.; Larson, B. W.; Hains, A. W.; Whitaker, J. B.; Kopidakis, N.; Boltalina, O. V.; Strauss, S. H.; Rumbles, G.

    2012-04-26

    A general but limiting characteristic in excitonic photovoltaics is that a portion of the incident photon energy appears necessary for converting excitons into electrical charges, resulting in a loss of efficiency. Currently, the mechanism underlying this process is unclear. Here, we describe the development of an experimental method for measuring charge creation yields in organic solar cell materials. We use this method to examine a series of conjugated polymer:fullerene blend films and observe two unexpected features: the existence of an optimal driving force and a loss in conversion efficiency if this force is exceeded. These observations have implications for the design of excitonic photovoltaic devices and can be explained by a simple Marcus formulation that introduces the importance of reorganization energy.

  17. A 1 MEGAWATT POLYPHASE BOOST CONVERTER-MODULATOR FOR KLYSTRON PULSE APPLICATION

    SciTech Connect (OSTI)

    W.A. REASS; J.D. DOSS; R.F. GRIBBLE

    2001-06-01

    This paper describes electrical design criteria and first operational results a 140 kV, 1 MW average, 11 MW peak, zero-voltage-switching 20 kHz polyphase bridge, boost converter/modulator for klystron pulse application. The DC-DC converter derives the buss voltages from a standard 13.8 kV to 2300 Y substation cast-core transformer. Energy storage and filtering is provided by self-clearing metallized hazy polypropylene traction capacitors. Three ''H-Bridge'' Insulated Gate Bipolar Transistor (IGBT) switching networks are used to generate the polyphase 20 kHz transformer primary drive waveforms. The 20 kHz drive waveforms are chirped the appropriate duration to generate the desired klystron pulse width. PWM (pulse width modulation) of the individual 20 kHz pulses is utilized to provide regulated output waveforms with adaptive feedforward and feedback techniques. The boost transformer design utilizes amorphous nanocrystalline material that provides the required low core loss at design flux levels and switching frequencies. Resonant shunt-peaking is used on the transformer secondary to boost output voltage and resonate transformer leakage inductance. With the appropriate transformer leakage inductance and peaking capacitance, zero-voltage-switching of the IGBT's is attained, minimizing switching losses. A review of these design parameters and the first results of the performance characteristics will be presented.

  18. Spin-transfer-torque efficiency enhanced by edge-damage of perpendicular magnetic random access memories

    SciTech Connect (OSTI)

    Song, Kyungmi; Lee, Kyung-Jin

    2015-08-07

    We numerically investigate the effect of magnetic and electrical damages at the edge of a perpendicular magnetic random access memory (MRAM) cell on the spin-transfer-torque (STT) efficiency that is defined by the ratio of thermal stability factor to switching current. We find that the switching mode of an edge-damaged cell is different from that of an undamaged cell, which results in a sizable reduction in the switching current. Together with a marginal reduction of the thermal stability factor of an edge-damaged cell, this feature makes the STT efficiency large. Our results suggest that a precise edge control is viable for the optimization of STT-MRAM.

  19. Optimization of spin-torque switching using AC and DC pulses

    SciTech Connect (OSTI)

    Dunn, Tom; Kamenev, Alex

    2014-06-21

    We explore spin-torque induced magnetic reversal in magnetic tunnel junctions using combined AC and DC spin-current pulses. We calculate the optimal pulse times and current strengths for both AC and DC pulses as well as the optimal AC signal frequency, needed to minimize the Joule heat lost during the switching process. The results of this optimization are compared against numeric simulations. Finally, we show how this optimization leads to different dynamic regimes, where switching is optimized by either a purely AC or DC spin-current, or a combination AC/DC spin-current, depending on the anisotropy energies and the spin-current polarization.

  20. Development of an ion-to-electron converter

    SciTech Connect (OSTI)

    Rachev, Mikhail; Srama, Ralf; Fettig, Rainer; Koehler, Uwe; Maas, Dieter; Gruen, Eberhard

    2005-06-15

    This article describes the design aspects of an ion-to-electron converter with a large area detector (approximately 450 cm{sup 2}). This converter was designed for a large area mass analyzer for the detection of cosmic dust particles. The design is based on the MM1 electron multiplier and the simulations were carried out using the software package SIMION 3D for the calculations of the electric field. Several dynode profiles were investigated in order to compare the time resolution and particle transmission. It is shown that the converter properties strongly depend on the dynode profile. Potential manufacturing processes are discussed briefly.

  1. Method for converting uranium oxides to uranium metal

    DOE Patents [OSTI]

    Duerksen, Walter K.

    1988-01-01

    A process is described for converting scrap and waste uranium oxide to uranium metal. The uranium oxide is sequentially reduced with a suitable reducing agent to a mixture of uranium metal and oxide products. The uranium metal is then converted to uranium hydride and the uranium hydride-containing mixture is then cooled to a temperature less than -100.degree. C. in an inert liquid which renders the uranium hydride ferromagnetic. The uranium hydride is then magnetically separated from the cooled mixture. The separated uranium hydride is readily converted to uranium metal by heating in an inert atmosphere. This process is environmentally acceptable and eliminates the use of hydrogen fluoride as well as the explosive conditions encountered in the previously employed bomb-reduction processes utilized for converting uranium oxides to uranium metal.

  2. Advanced Wave Energy Converters (WEC) Dynamics and Controls Webinar...

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

    Wave Energy Converters (WEC) Dynamics and Controls Webinar: June 6, 2016 at 2:00 p.m. EDT ... Secure & Sustainable Energy Future Stationary Power Energy Conversion Efficiency Solar ...

  3. Sensitivity of a Wave Energy Converter Dynamics Model to Nonlinear...

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

    surface in- tegral based method. NOMENCLATURE WEC Wave energy converter. T3R2 "Three-translation, two-rotation" WEC studied here. PCC Power-conversion-chain. PMT...

  4. Non-synchronous control of self-oscillating resonant converters

    DOE Patents [OSTI]

    Glaser, John Stanley (Niskayuna, NY); Zane, Regan Andrew (Scotia, NY)

    2002-01-01

    A self-oscillating switching power converter has a controllable reactance including an active device connected to a reactive element, wherein the effective reactance of the reactance and the active device is controlled such that the control waveform for the active device is binary digital and is not synchronized with the switching converter output frequency. The active device is turned completely on and off at a frequency that is substantially greater than the maximum frequency imposed on the output terminals of the active device. The effect is to vary the average resistance across the active device output terminals, and thus the effective output reactance, thereby providing converter output control, while maintaining the response speed of the converter.

  5. Vehicle Technologies Office Merit Review 2014: WBG Converters and Chargers

    Broader source: Energy.gov [DOE]

    Presentation given by Oak Ridge National Laboratory at 2014 DOE Hydrogen and Fuel Cells Program and Vehicle Technologies Office Annual Merit Review and Peer Evaluation Meeting about WBG converters...

  6. Magnetic rogue wave in a perpendicular anisotropic ferromagnetic nanowire with spin-transfer torque

    SciTech Connect (OSTI)

    Zhao, Fei; Li, Zai-Dong; Li, Qiu-Yan; Wen, Lin; Fu, Guangsheng; Liu, W.M.

    2012-09-15

    We present the current controlled motion of a dynamic soliton embedded in spin wave background in ferromagnetic nanowire. With the stronger breather character we get the novel magnetic rogue wave and clarify its formation mechanism. The generation of magnetic rogue wave mainly arises from the accumulation of energy and magnons toward to its central part. We also observe that the spin-polarized current can control the exchange rate of magnons between the envelope soliton and the background, and the critical current condition is obtained analytically. Even more interesting is that the spin-transfer torque plays the completely opposite role for the cases below and above the critical value. - Highlights: Black-Right-Pointing-Pointer We get the current controlled motion of a dynamic soliton embedded in spin wave background. Black-Right-Pointing-Pointer We get the novel magnetic rogue wave and clarify its formation mechanism. Black-Right-Pointing-Pointer The generation of magnetic rogue wave arises from the accumulation of energy and magnons. Black-Right-Pointing-Pointer The spin-polarized current controls exchange rate of magnons between the envelope soliton and the background. Black-Right-Pointing-Pointer The spin-transfer torque plays the completely opposite role below and above the critical value.

  7. Ultrafast spin exchange-coupling torque via photo-excited charge-transfer processes

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

    Ma, X.; Fang, F.; Li, Q.; Zhu, J.; Yang, Y.; Wu, Y. Z.; Zhao, H. B.; Lüpke, G.

    2015-10-28

    In this study, optical control of spin is of central importance in the research of ultrafast spintronic devices utilizing spin dynamics at short time scales. Recently developed optical approaches such as ultrafast demagnetization, spin-transfer and spin-orbit torques open new pathways to manipulate spin through its interaction with photon, orbit, charge or phonon. However, these processes are limited by either the long thermal recovery time or the low-temperature requirement. Here we experimentally demonstrate ultrafast coherent spin precession via optical charge-transfer processes in the exchange-coupled Fe/CoO system at room temperature. The efficiency of spin precession excitation is significantly higher and the recoverymore » time of the exchange-coupling torque is much shorter than for the demagnetization procedure, which is desirable for fast switching. The exchange coupling is a key issue in spin valves and tunnelling junctions, and hence our findings will help promote the development of exchange-coupled device concepts for ultrafast coherent spin manipulation.« less

  8. Ultrafast spin exchange-coupling torque via photo-excited charge-transfer processes

    SciTech Connect (OSTI)

    Ma, X.; Fang, F.; Li, Q.; Zhu, J.; Yang, Y.; Wu, Y. Z.; Zhao, H. B.; Lüpke, G.

    2015-10-28

    In this study, optical control of spin is of central importance in the research of ultrafast spintronic devices utilizing spin dynamics at short time scales. Recently developed optical approaches such as ultrafast demagnetization, spin-transfer and spin-orbit torques open new pathways to manipulate spin through its interaction with photon, orbit, charge or phonon. However, these processes are limited by either the long thermal recovery time or the low-temperature requirement. Here we experimentally demonstrate ultrafast coherent spin precession via optical charge-transfer processes in the exchange-coupled Fe/CoO system at room temperature. The efficiency of spin precession excitation is significantly higher and the recovery time of the exchange-coupling torque is much shorter than for the demagnetization procedure, which is desirable for fast switching. The exchange coupling is a key issue in spin valves and tunnelling junctions, and hence our findings will help promote the development of exchange-coupled device concepts for ultrafast coherent spin manipulation.

  9. DYNAMIC ANALYSIS OF THE BULK TRITIUM SHIPPING PACKAGE SUBJECTED TO CLOSURE TORQUES AND SEQUENTIAL IMPACTS

    SciTech Connect (OSTI)

    Wu, T; Paul Blanton, P; Kurt Eberl, K

    2007-07-09

    This paper presents a finite-element technique to simulate the structural responses and to evaluate the cumulative damage of a radioactive material packaging requiring bolt closure-tightening torque and subjected to the scenarios of the Hypothetical Accident Conditions (HAC) defined in the Code of Federal Regulations Title 10 part 71 (10CFR71). Existing finite-element methods for modeling closure stresses from bolt pre-load are not readily adaptable to dynamic analyses. The HAC events are required to occur sequentially per 10CFR71 and thus the evaluation of the cumulative damage is desirable. Generally, each HAC event is analyzed separately and the cumulative damage is partially addressed by superposition. This results in relying on additional physical testing to comply with 10CFR71 requirements for assessment of cumulative damage. The proposed technique utilizes the combination of kinematic constraints, rigid-body motions and structural deformations to overcome some of the difficulties encountered in modeling the effect of cumulative damage. This methodology provides improved numerical solutions in compliance with the 10CFR71 requirements for sequential HAC tests. Analyses were performed for the Bulk Tritium Shipping Package (BTSP) designed by Savannah River National Laboratory to demonstrate the applications of the technique. The methodology proposed simulates the closure bolt torque preload followed by the sequential HAC events, the 30-foot drop and the 30-foot dynamic crush. The analytical results will be compared to the package test data.

  10. Converter Topologies for Wired and Wireless Battery Chargers | Department

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

    of Energy 2 DOE Hydrogen and Fuel Cells Program and Vehicle Technologies Program Annual Merit Review and Peer Evaluation Meeting ape033_su_2012_o.pdf (655.46 KB) More Documents & Publications Converter Topologies for Wired and Wireless Battery Chargers Utilizing the Traction Drive Power Electronics System to Provide Plug-in Capability for PHEVs Vehicle Technologies Office Merit Review 2014: WBG Converters and Chargers

  11. Microsoft PowerPoint - Converting Sustainable Forest Products into Fuel

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

    Converting Sustainable Forest Products into Fuel: What it takes to have a successful wood pellet manufacturing business Presented at The Biomass Renewable Energy Opportunities and Strategies Forum July 9, 2014 Converting Sustainable Forest Products into Fuel: What it takes to have a successful wood pellet manufacturing business Presented at The Biomass Renewable Energy Opportunities and Strategies Forum July 9, 2014 Presented by Dr. William Strauss President, FutureMetrics Director, Maine Energy

  12. Converting energy to medical progress [nuclear medicine] (Technical Report)

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

    | SciTech Connect Converting energy to medical progress [nuclear medicine] Citation Details In-Document Search Title: Converting energy to medical progress [nuclear medicine] × You are accessing a document from the Department of Energy's (DOE) SciTech Connect. This site is a product of DOE's Office of Scientific and Technical Information (OSTI) and is provided as a public service. Visit OSTI to utilize additional information resources in energy science and technology. A paper copy of this

  13. Bi-directional power control system for voltage converter

    DOE Patents [OSTI]

    Garrigan, N.R.; King, R.D.; Schwartz, J.E.

    1999-05-11

    A control system for a voltage converter includes: a power comparator for comparing a power signal on input terminals of the converter with a commanded power signal and producing a power comparison signal; a power regulator for transforming the power comparison signal to a commanded current signal; a current comparator for comparing the commanded current signal with a measured current signal on output terminals of the converter and producing a current comparison signal; a current regulator for transforming the current comparison signal to a pulse width modulator (PWM) duty cycle command signal; and a PWM for using the PWM duty cycle command signal to control electrical switches of the converter. The control system may further include: a command multiplier for converting a voltage signal across the output terminals of the converter to a gain signal having a value between zero (0) and unity (1), and a power multiplier for multiplying the commanded power signal by the gain signal to provide a limited commanded power signal, wherein power comparator compares the limited commanded power signal with the power signal on the input terminals. 10 figs.

  14. Bi-directional power control system for voltage converter

    DOE Patents [OSTI]

    Garrigan, Neil Richard; King, Robert Dean; Schwartz, James Edward

    1999-01-01

    A control system for a voltage converter includes: a power comparator for comparing a power signal on input terminals of the converter with a commanded power signal and producing a power comparison signal; a power regulator for transforming the power comparison signal to a commanded current signal; a current comparator for comparing the commanded current signal with a measured current signal on output terminals of the converter and producing a current comparison signal; a current regulator for transforming the current comparison signal to a pulse width modulator (PWM) duty cycle command signal; and a PWM for using the PWM duty cycle command signal to control electrical switches of the converter. The control system may further include: a command multiplier for converting a voltage signal across the output terminals of the converter to a gain signal having a value between zero (0) and unity (1), and a power multiplier for multiplying the commanded power signal by the gain signal to provide a limited commanded power signal, wherein power comparator compares the limited commanded power signal with the power signal on the input terminals.

  15. 3-Port Single-Stage PV & Battery Converter Improves Efficiency and Cost in Combined PV/Battery Systems

    SciTech Connect (OSTI)

    Bundschuh, Paul

    2013-03-23

    Due to impressive cost reductions in recent years, photovoltaic (PV) generation is now able to produce electricity at highly competitive prices, but PV’s inherent intermittency reduces the potential value of this energy. The integration of battery storage with PV will be transformational by increasing the value of solar. Utility scale systems will benefit by firming intermittency including PV ramp smoothing, grid support and load shifting, allowing PV to compete directly with conventional generation. For distributed grid-tied PV adding storage will reduce peak demand utility charges, as well as providing backup power during power grid failures. The largest long term impact of combined PV and battery systems may be for delivering reliable off-grid power to the billions of individuals globally without access to conventional power grids, or for billions more that suffer from daily power outages. PV module costs no longer dominate installed PV system costs. Balance-of-System (BOS) costs including the PV inverter and installation now contribute the majority of installed system costs. Battery costs are also dropping faster than installation and battery power converter systems. In each of these separate systems power converters have become a bottleneck for efficiency, cost and reliability. These bottlenecks are compounded in hybrid power conversion systems that combine separate PV and battery converters. Hybrid power conversion systems have required multiple power converters hardware units and multiple power conversion steps adding to efficiency losses, product and installation costs, and reliability issues. Ideal Power Converters has developed and patented a completely new theory of operation for electronic power converters using its indirect EnergyPacket Switching™ topology. It has established successful power converter products for both PV and battery systems, and its 3-Port Hybrid Converter is the first product to exploit the topology’s capability for the

  16. Minimizing Energy Losses in Ducts

    Broader source: Energy.gov [DOE]

    Insulating, air sealing, and placing ducts within the conditioned space of your home will reduce energy losses.

  17. Motor torque compensation of an induction electric motor by adjusting a slip command during periods of supposed change in motor temperature

    DOE Patents [OSTI]

    Kelledes, William L.; St. John, Don K.

    1992-01-01

    The present invention maintains constant torque in an inverter driven AC induction motor during variations in rotor temperature. It is known that the torque output of a given AC induction motor is dependent upon rotor temperature. At rotor temperatures higher than the nominal operating condition the rotor impedance increases, reducing the rotor current and motor torque. In a similar fashion, the rotor impedance is reduced resulting in increased rotor current and motor torque when the rotor temperature is lower than the nominal operating condition. The present invention monitors the bus current from the DC supply to the inverter and adjusts the slip frequency of the inverter drive to maintain a constant motor torque. This adjustment is based upon whether predetermined conditions implying increased rotor temperature or decreased rotor temperature exist for longer that a predetermined interval of time.

  18. Probing CP Violation in $h\\rightarrow\\gamma\\gamma$ with Converted...

    Office of Scientific and Technical Information (OSTI)

    CP Violation in hrightarrowgammagamma with Converted Photons Citation Details In-Document Search Title: Probing CP Violation in hrightarrowgammagamma with Converted...

  19. DOE-TSPP-8-2013, Converting DOE Technical Standards to Voluntary...

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

    8-2013, Converting DOE Technical Standards to Voluntary Consensus Standards DOE-TSPP-8-2013, Converting DOE Technical Standards to Voluntary Consensus Standards Technical Standards ...

  20. Mode-hopping mechanism generating colored noise in a magnetic tunnel junction based spin torque oscillator

    SciTech Connect (OSTI)

    Sharma, Raghav; Drrenfeld, P.; Iacocca, E.; Heinonen, O. G.; kerman, J.; Muduli, P. K.

    2014-09-29

    The frequency noise spectrum of a magnetic tunnel junction based spin torque oscillator is examined where multiple modes and mode-hopping events are observed. The frequency noise spectrum is found to consist of both white noise and 1/f frequency noise. We find a systematic and similar dependence of both white noise and 1/f frequency noise on bias current and the relative angle between the reference and free layers, which changes the effective damping and hence the mode-hopping behavior in this system. The frequency at which the 1/f frequency noise changes to white noise increases as the free layer is aligned away from the anti-parallel orientation w.r.t the reference layer. These results indicate that the origin of 1/f frequency noise is related to mode-hopping, which produces both white noise as well as 1/f frequency noise similar to the case of ring lasers.

  1. Enhancement of the anti-damping spin torque efficacy of platinum by interface modification

    SciTech Connect (OSTI)

    Nguyen, Minh-Hai; Pai, Chi-Feng; Nguyen, Kayla X.; Buhrman, R. A.; Muller, David A.; Ralph, D. C.

    2015-06-01

    We report a strong enhancement of the efficacy of the spin Hall effect (SHE) of Pt for exerting anti-damping spin torque on an adjacent ferromagnetic layer by the insertion of ≈0.5 nm layer of Hf between a Pt film and a thin, ≤2 nm, Fe{sub 60}Co{sub 20}B{sub 20} ferromagnetic layer. This enhancement is quantified by measurement of the switching current density when the ferromagnetic layer is the free electrode in a magnetic tunnel junction. The results are explained as the suppression of spin pumping through a substantial decrease in the effective spin-mixing conductance of the interface, but without a concomitant reduction of the ferromagnet's absorption of the SHE generated spin current.

  2. Spin orbital torque driven magnetization switching in magnetic tunnel junction with inter-layer exchange coupling

    SciTech Connect (OSTI)

    Xu, Lei; Ma, Zhongshui; Wei, Dan

    2015-01-14

    The switching processes of elliptically shaped magnetic tunnel junction bits with the structure Ta/CoFeB/MgO/CoFeB have been studied by the micromagnetic models. By comparing the tunneling magneto-resistance minor and major loops calculated by our model with related experimental results, we found that the inter-layer exchange coupling between the two CoFeB layers and a reduced saturation magnetization M{sub s} distribution at the edge of the elliptical bit should be included. The chosen strength of the inter-layer exchange coupling also matches well with experimental observations. The current induced magnetization switching is generated from the spin Hall effect in the Ta layer. The critical switching currents calculated by our model are coincident with experiment. This shows the reliability of our micromagnetic model with the spin orbital torque term.

  3. Quantification of the spin-Hall anti-damping torque with a resonance spectrometer

    SciTech Connect (OSTI)

    Emori, Satoru Nan, Tianxiang; Oxholm, Trevor M.; Boone, Carl T.; Sun, Nian X.; Jones, John G.; Howe, Brandon M.; Brown, Gail J.; Budil, David E.

    2015-01-12

    We present a simple technique using a cavity-based resonance spectrometer to quantify the anti-damping torque due to the spin Hall effect. Modification of ferromagnetic resonance is observed as a function of small DC current in sub-mm-wide strips of bilayers, consisting of magnetically soft FeGaB and strong spin-Hall metal Ta. From the detected current-induced linewidth change, we obtain an effective spin Hall angle of 0.08–0.09 independent of the magnetic layer thickness. Our results demonstrate that a sensitive resonance spectrometer can be a general tool to investigate spin Hall effects in various material systems, even those with vanishingly low conductivity and magnetoresistance.

  4. Fast deterministic switching in orthogonal spin torque devices via the control of the relative spin polarizations

    SciTech Connect (OSTI)

    Park, Junbo; Buhrman, R. A.; Ralph, D. C.; Kavli Institute at Cornell, Ithaca, New York 14853

    2013-12-16

    We model 100 ps pulse switching dynamics of orthogonal spin transfer (OST) devices that employ an out-of-plane polarizer and an in-plane polarizer. Simulation results indicate that increasing the spin polarization ratio, C{sub P}?=?P{sub IPP}/P{sub OPP}, results in deterministic switching of the free layer without over-rotation (360 rotation). By using spin torque asymmetry to realize an enhanced effective P{sub IPP}, we experimentally demonstrate this behavior in OST devices in parallel to anti-parallel switching. Modeling predicts that decreasing the effective demagnetization field can substantially reduce the minimum C{sub P} required to attain deterministic switching, while retaining low critical switching current, I{sub p}???500??A.

  5. Low torque hydrodynamic lip geometry for bi-directional rotation seals

    DOE Patents [OSTI]

    Dietle, Lannie L.; Schroeder, John E.

    2009-07-21

    A hydrodynamically lubricating geometry for the generally circular dynamic sealing lip of rotary seals that are employed to partition a lubricant from an environment. The dynamic sealing lip is provided for establishing compressed sealing engagement with a relatively rotatable surface, and for wedging a film of lubricating fluid into the interface between the dynamic sealing lip and the relatively rotatable surface in response to relative rotation that may occur in the clockwise or the counter-clockwise direction. A wave form incorporating an elongated dimple provides the gradual convergence, efficient impingement angle, and gradual interfacial contact pressure rise that are conducive to efficient hydrodynamic wedging. Skewed elevated contact pressure zones produced by compression edge effects provide for controlled lubricant movement within the dynamic sealing interface between the seal and the relatively rotatable surface, producing enhanced lubrication and low running torque.

  6. Low torque hydrodynamic lip geometry for bi-directional rotation seals

    DOE Patents [OSTI]

    Dietle, Lannie L.; Schroeder, John E.

    2011-11-15

    A hydrodynamically lubricating geometry for the generally circular dynamic sealing lip of rotary seals that are employed to partition a lubricant from an environment. The dynamic sealing lip is provided for establishing compressed sealing engagement with a relatively rotatable surface, and for wedging a film of lubricating fluid into the interface between the dynamic sealing lip and the relatively rotatable surface in response to relative rotation that may occur in the clockwise or the counter-clockwise direction. A wave form incorporating an elongated dimple provides the gradual convergence, efficient impingement angle, and gradual interfacial contact pressure rise that are conducive to efficient hydrodynamic wedging. Skewed elevated contact pressure zones produced by compression edge effects provide for controlled lubricant movement within the dynamic sealing interface between the seal and the relatively rotatable surface, producing enhanced lubrication and low running torque.

  7. Auxiliary quasi-resonant dc tank electrical power converter

    DOE Patents [OSTI]

    Peng, Fang Z.

    2006-10-24

    An auxiliary quasi-resonant dc tank (AQRDCT) power converter with fast current charging, voltage balancing (or charging), and voltage clamping circuits is provided for achieving soft-switched power conversion. The present invention is an improvement of the invention taught in U.S. Pat. No. 6,111,770, herein incorporated by reference. The present invention provides faster current charging to the resonant inductor, thus minimizing delay time of the pulse width modulation (PWM) due to the soft-switching process. The new AQRDCT converter includes three tank capacitors or power supplies to achieve the faster current charging and minimize the soft-switching time delay. The new AQRDCT converter further includes a voltage balancing circuit to charge and discharge the three tank capacitors so that additional isolated power supplies from the utility line are not needed. A voltage clamping circuit is also included for clamping voltage surge due to the reverse recovery of diodes.

  8. Methods for degrading or converting plant cell wall polysaccharides

    DOE Patents [OSTI]

    Berka, Randy; Cherry, Joel

    2008-08-19

    The present invention relates to methods for converting plant cell wall polysaccharides into one or more products, comprising: treating the plant cell wall polysaccharides with an effective amount of a spent whole fermentation broth of a recombinant microorganism, wherein the recombinant microorganism expresses one or more heterologous genes encoding enzymes which degrade or convert the plant cell wall polysaccharides into the one or more products. The present invention also relates to methods for producing an organic substance, comprising: (a) saccharifying plant cell wall polysaccharides with an effective amount of a spent whole fermentation broth of a recombinant microorganism, wherein the recombinant microorganism expresses one or more heterologous genes encoding enzymes which degrade or convert the plant cell wall polysaccharides into saccharified material; (b) fermenting the saccharified material of step (a) with one or more fermenting microoganisms; and (c) recovering the organic substance from the fermentation.

  9. Reducing cold-start emissions by catalytic converter thermal management

    SciTech Connect (OSTI)

    Burch, S D; Potter, T F; Keyser, M A; Brady, M J; Michaels, K F

    1995-01-01

    Vacuum insulation and phase-change thermal storage have been used to enhance the heat retention of a prototype catalytic converter. Storing heat in the converter between trips allows exhaust gases to be converted more quickly, significantly reducing cold-start emissions. Using a small metal hydride, the thermal conductance of the vacuum insulation can be varied continuously between 0.49 and 27 W/m{sup 2}K (R-12 to R-0.2 insulation) to prevent overheating of the catalyst. A prototype was installed in a Dodge Neon with a 2.0-liter engine. Following a standard preconditioning and a 23-hour cold soak, an FTP (Federal Test Procedure) emissions test was performed. Although exhaust temperatures during the preconditioning were not hot enough to melt the phase-change material, the vacuum insulation performed well, resulting in a converter temperature of 146{degrees}C after the 23-hour cold soak at 27{degrees}C. Compared to the same converter at ambient conditions, overall emissions of CO and HC were reduced by 52 % and 29 %, to 0.27 and 0.037 g/mile, respectively. The maximum converter temperature during the FTP cycle was 720{degrees}C. This limited testing was performed with a nearly-fresh palladium-only catalyst, but demonstrates the potential of this vacuum insulation approach for emissions reduction and thermal control. Further testing is ongoing. An initial assessment of several production issues is made, including high-volume fabrication challenges, durability, and cost.

  10. Process for converting cellulosic materials into fuels and chemicals

    DOE Patents [OSTI]

    Scott, Charles D.; Faison, Brendlyn D.; Davison, Brian H.; Woodward, Jonathan

    1994-01-01

    A process for converting cellulosic materials, such as waste paper, into fuels and chemicals utilizing enzymatic hydrolysis of the major constituent of paper, cellulose. A waste paper slurry is contacted by cellulase in an agitated hydrolyzer. The cellulase is produced from a continuous, columnar, fluidized-bed bioreactor utilizing immobilized microorganisms. An attritor and a cellobiase reactor are coupled to the agitated hydrolyzer to improve reaction efficiency. The cellulase is recycled by an adsorption process. The resulting crude sugars are converted to dilute product in a fluidized-bed bioreactor utilizing microorganisms. The dilute product is concentrated and purified by utilizing distillation and/or a biparticle fluidized-bed bioreactor system.

  11. Method for converting sucrose to .beta.-D-glucose

    DOE Patents [OSTI]

    Simmons, Blake A.; Volponi, Joanne V.; Ingersoll, David; Walker, Andrew

    2009-07-07

    Disclosed is an apparatus and method for continuously converting sucrose to .beta.-D-glucose. The method comprises a three-stage enzymatic reactor in which an aqueous solution of sucrose is first converted into a solution of fructose and .alpha.-D-glucose by passing it through a porous, packed column containing an inert media on which invertase is immobilized. This solution is then sent through a second packed column containing glucose isomerase and finally a third packed column containing mutarotase. Solution temperature and pH are adjusted to maximize glucose output.

  12. Method for reducing energy losses in laser crystals

    DOE Patents [OSTI]

    Atherton, L.J.; DeYoreo, J.J.; Roberts, D.H.

    1992-03-24

    A process for reducing energy losses in crystals is disclosed which comprises: a. heating a crystal to a temperature sufficiently high as to cause dissolution of microscopic inclusions into the crystal, thereby converting said inclusions into point-defects, and b. maintaining said crystal at a given temperature for a period of time sufficient to cause said point-defects to diffuse out of said crystal. Also disclosed are crystals treated by the process, and lasers utilizing the crystals as a source of light. 12 figs.

  13. Method for reducing energy losses in laser crystals

    DOE Patents [OSTI]

    Atherton, L. Jeffrey; DeYoreo, James J.; Roberts, David H.

    1992-01-01

    A process for reducing energy losses in crystals is disclosed which comprises: a. heating a crystal to a temperature sufficiently high as to cause dissolution of microscopic inclusions into the crystal, thereby converting said inclusions into point-defects, and b. maintaining said crystal at a given temperature for a period of time sufficient to cause said point-defects to diffuse out of said crystal. Also disclosed are crystals treated by the process, and lasers utilizing the crystals as a source of light.

  14. Minimize Boiler Short Cycling Losses

    Office of Energy Efficiency and Renewable Energy (EERE)

    This tip sheet on minimizing boiler short cycling losses provides how-to advice for improving industrial steam systems using low-cost, proven practices and technologies.

  15. Everything Digital: Converting the world in 2 Exabytes

    SciTech Connect (OSTI)

    Lesk, Michael

    2003-11-05

    Nearly everything created today is in digital format: music is on digital CDs, documents come from word processing, still photography is switching to digital cameras and even movies are now edited digitally. What about the past? We have projects like the Million Book Project scanning one million books, and we know technically how to convert everything: the problems are legal, economic and organizational.

  16. Energy Savings Assessment for Digital-to-Analog Converter Boxes

    SciTech Connect (OSTI)

    Cheung, Hoi Ying Iris; Meier, Alan; Brown, Richard

    2011-01-18

    The Digital Television (DTV) Converter Box Coupon Program was administered by the U.S. government to subsidize purchases of digital-to-analog converter boxes, with up to two $40 coupons for each eligible household. In order to qualify as Coupon Eligible Converter Boxes (CECBs), these devices had to meet a number of minimum performance specifications, including energy efficiency standards. The Energy Star Program also established voluntary energy efficiency specifications that are more stringent than the CECB requirements. In this study, we measured the power and energy consumptions for a sample of 12 CECBs (including 6 Energy Star labeled models) in-use in homes and estimated aggregate energy savings produced by the energy efficiency policies. Based on the 35 million coupons redeemed through the end of the program, our analysis indicates that between 2500 and 3700 GWh per year are saved as a result of the energy efficiency policies implemented on digital-to-analog converter boxes. The energy savings generated are equivalent to the annual electricity use of 280,000 average US homes.

  17. Pre-converted nitric oxide gas in catalytic reduction system

    DOE Patents [OSTI]

    Hsiao, Mark C.; Merritt, Bernard T.; Penetrante, Bernardino M.; Vogtlin, George E.

    1999-01-01

    A two-stage catalyst comprises an oxidative first stage and a reductive second stage. The first stage is intended to convert NO to NO.sub.2 in the presence of O.sub.2. The second stage serves to convert NO.sub.2 to environmentally benign gases that include N2, CO2, and H.sub.2 O. By preconverting NO to NO.sub.2 in the first stage, the efficiency of the second stage for NO.sub.x reduction is enhanced. For example, an internal combustion engine exhaust is connected by a pipe to a first chamber. An oxidizing first catalyst converts NO to NO.sub.2 in the presence of O.sub.2 and includes platinum/alumina, e.g., Pt/Al.sub.2 O.sub.3 catalyst. A flow of hydrocarbons (C.sub.x H.sub.y) is input from a pipe into a second chamber. For example, propene can be used as a source of hydrocarbons. The NO.sub.2 from the first catalyst mixes with the hydrocarbons in the second chamber. The mixture proceeds to a second reduction catalyst that converts NO.sub.2 to N2, CO2, and H.sub.2 O, and includes a gamma-alumina .gamma.-Al.sub.2 O.sub.3. The hydrocarbons and NO.sub.x are simultaneously reduced while passing through the second catalyst.

  18. Apparatus for converting biomass to a pumpable slurry

    DOE Patents [OSTI]

    Ergun, Sabri; Schaleger, Larry L.; Wrathall, James A.; Yaghoubzadeh, Nasser

    1986-01-01

    An apparatus used in the pretreatment of wood chips in a process for converting biomass to a liquid hydrocarbonaceous fuel. The apparatus functions to break down the wood chips to a size distribution that can be readily handled in a slurry form. Low maintenance operation is obtained by hydrolyzing the chips in a pressure vessel having no moving parts.

  19. Pre-converted nitric oxide gas in catalytic reduction system

    DOE Patents [OSTI]

    Hsiao, M.C.; Merritt, B.T.; Penetrante, B.M.; Vogtlin, G.E.

    1999-04-06

    A two-stage catalyst comprises an oxidative first stage and a reductive second stage. The first stage is intended to convert NO to NO{sub 2} in the presence of O{sub 2}. The second stage serves to convert NO{sub 2} to environmentally benign gases that include N{sub 2}, CO{sub 2}, and H{sub 2}O. By preconverting NO to NO{sub 2} in the first stage, the efficiency of the second stage for NO{sub x} reduction is enhanced. For example, an internal combustion engine exhaust is connected by a pipe to a first chamber. An oxidizing first catalyst converts NO to NO{sub 2} in the presence of O{sub 2} and includes platinum/alumina, e.g., Pt/Al{sub 2}O{sub 3} catalyst. A flow of hydrocarbons (C{sub x}H{sub y}) is input from a pipe into a second chamber. For example, propene can be used as a source of hydrocarbons. The NO{sub 2} from the first catalyst mixes with the hydrocarbons in the second chamber. The mixture proceeds to a second reduction catalyst that converts NO{sub 2} to N{sub 2}, CO{sub 2}, and H{sub 2}O, and includes a {gamma}-Al{sub 2}O{sub 3}. The hydrocarbons and NO{sub x} are simultaneously reduced while passing through the second catalyst. 9 figs.

  20. Northwest Energy Innovations (TRL 5 6 System)- WETNZ MtiMode Wave Energy Converter Advancement Project

    Office of Energy Efficiency and Renewable Energy (EERE)

    Northwest Energy Innovations (TRL 5 6 System) - WETNZ MtiMode Wave Energy Converter Advancement Project

  1. Alternative Fuels Data Center: Yellow Cab Converts Taxis to Propane in

    Alternative Fuels and Advanced Vehicles Data Center [Office of Energy Efficiency and Renewable Energy (EERE)]

    Columbus, Ohio Yellow Cab Converts Taxis to Propane in Columbus, Ohio to someone by E-mail Share Alternative Fuels Data Center: Yellow Cab Converts Taxis to Propane in Columbus, Ohio on Facebook Tweet about Alternative Fuels Data Center: Yellow Cab Converts Taxis to Propane in Columbus, Ohio on Twitter Bookmark Alternative Fuels Data Center: Yellow Cab Converts Taxis to Propane in Columbus, Ohio on Google Bookmark Alternative Fuels Data Center: Yellow Cab Converts Taxis to Propane in

  2. Observations of thermally excited ferromagnetic resonance on spin torque oscillators having a perpendicularly magnetized free layer

    SciTech Connect (OSTI)

    Tamaru, S. Kubota, H.; Yakushiji, K.; Konoto, M.; Nozaki, T.; Fukushima, A.; Imamura, H.; Taniguchi, T.; Arai, H.; Tsunegi, S.; Yuasa, S.; Suzuki, Y.

    2014-05-07

    Measurements of thermally excited ferromagnetic resonance were performed on spin torque oscillators having a perpendicularly magnetized free layer and in-plane magnetized reference layer (abbreviated as PMF-STO in the following) for the purpose of obtaining magnetic properties in the PMF-STO structure. The measured spectra clearly showed a large main peak and multiple smaller peaks on the high frequency side. A Lorentzian fit on the main peak yielded Gilbert damping factor of 0.0041. The observed peaks moved in proportion to the out-of-plane bias field. From the slope of the main peak frequency as a function of the bias field, Lande g factor was estimated to be about 2.13. The mode intervals showed a clear dependence on the diameter of the PMF-STOs, i.e., intervals are larger for a smaller diameter. These results suggest that the observed peaks should correspond to eigenmodes of lateral spin wave resonance in the perpendicularly magnetized free layer.

  3. Dependence of the colored frequency noise in spin torque oscillators on current and magnetic field

    SciTech Connect (OSTI)

    Eklund, Anders Sani, Sohrab R.; Chung, Sunjae; Amir Hossein Banuazizi, S.; stling, Mikael; Gunnar Malm, B.; Bonetti, Stefano; Majid Mohseni, S.; Persson, Johan; Iacocca, Ezio; kerman, Johan

    2014-03-03

    The nano-scale spin torque oscillator (STO) is a compelling device for on-chip, highly tunable microwave frequency signal generation. Currently, one of the most important challenges for the STO is to increase its longer-time frequency stability by decreasing the 1/f frequency noise, but its high level makes even its measurement impossible using the phase noise mode of spectrum analyzers. Here, we present a custom made time-domain measurement system with 150?MHz measurement bandwidth making possible the investigation of the variation of the 1/f as well as the white frequency noise in a STO over a large set of operating points covering 1825?GHz. The 1/f level is found to be highly dependent on the oscillation amplitude-frequency non-linearity and the vicinity of unexcited oscillation modes. These findings elucidate the need for a quantitative theoretical treatment of the low-frequency, colored frequency noise in STOs. Based on the results, we suggest that the 1/f frequency noise possibly can be decreased by improving the microstructural quality of the metallic thin films.

  4. Electromagnetic analysis of forces and torques on the baseline and enhanced ITER shield modules due to plasma disruption.

    SciTech Connect (OSTI)

    Kotulski, Joseph Daniel; Coats, Rebecca Sue; Pasik, Michael Francis; Ulrickson, Michael Andrew

    2009-08-01

    An electromagnetic analysis is performed on the ITER shield modules under different plasma-disruption scenarios using the OPERA-3d software. The models considered include the baseline design as provided by the International Organization and an enhanced design that includes the more realistic geometrical features of a shield module. The modeling procedure is explained, electromagnetic torques are presented, and results of the modeling are discussed.

  5. Discharging a DC bus capacitor of an electrical converter system

    DOE Patents [OSTI]

    Kajouke, Lateef A; Perisic, Milun; Ransom, Ray M

    2014-10-14

    A system and method of discharging a bus capacitor of a bidirectional matrix converter of a vehicle are presented here. The method begins by electrically shorting the AC interface of the converter after an AC energy source is disconnected from the AC interface. The method continues by arranging a plurality of switching elements of a second energy conversion module into a discharge configuration to establish an electrical current path from a first terminal of an isolation module, through an inductive element, and to a second terminal of the isolation module. The method also modulates a plurality of switching elements of a first energy conversion module, while maintaining the discharge configuration of the second energy conversion module, to at least partially discharge a DC bus capacitor.

  6. CONVERTING PYROLYSIS OILS TO RENEWABLE TRANSPORT FUELS: PROCESSING CHALLENGES & OPPORTUNITIES

    SciTech Connect (OSTI)

    Holmgren, Jennifer; Nair, Prabhakar N.; Elliott, Douglas C.; Bain, Richard; Marinangelli, Richard

    2008-03-11

    To enable a sustained supply of biomass-based transportation fuels, the capability to process feedstocks outside the food chain must be developed. Significant industry efforts are underway to develop these new technologies, such as converting cellulosic wastes to ethanol. UOP, in partnership with U.S. Government labs, NREL and PNNL, is developing an alternate route using cellulosic feedstocks. The waste biomass is first subjected to a fast pyrolysis operation to generate pyrolysis oil (pyoil for short). Current efforts are focused on developing a thermochemical platform to convert pyoils to renewable gasoline, diesel and jet fuel. The fuels produced will be indistinguishable from their fossil fuel counterparts and, therefore, will be compatible with existing transport and distribution infrastructure.

  7. Ultrafast transient grating radiation to optical image converter

    DOE Patents [OSTI]

    Stewart, Richard E; Vernon, Stephen P; Steel, Paul T; Lowry, Mark E

    2014-11-04

    A high sensitivity transient grating ultrafast radiation to optical image converter is based on a fixed transmission grating adjacent to a semiconductor substrate. X-rays or optical radiation passing through the fixed transmission grating is thereby modulated and produces a small periodic variation of refractive index or transient grating in the semiconductor through carrier induced refractive index shifts. An optical or infrared probe beam tuned just below the semiconductor band gap is reflected off a high reflectivity mirror on the semiconductor so that it double passes therethrough and interacts with the radiation induced phase grating therein. A small portion of the optical beam is diffracted out of the probe beam by the radiation induced transient grating to become the converted signal that is imaged onto a detector.

  8. Process for converting cellulosic materials into fuels and chemicals

    DOE Patents [OSTI]

    Scott, C.D.; Faison, B.D.; Davison, B.H.; Woodward, J.

    1994-09-20

    A process is described for converting cellulosic materials, such as waste paper, into fuels and chemicals utilizing enzymatic hydrolysis of the major constituent of paper, cellulose. A waste paper slurry is contacted by cellulase in an agitated hydrolyzer. The cellulase is produced from a continuous, columnar, fluidized-bed bioreactor utilizing immobilized microorganisms. An attrition mill and a cellobiase reactor are coupled to the agitated hydrolyzer to improve reaction efficiency. The cellulase is recycled by an adsorption process. The resulting crude sugars are converted to dilute product in a fluidized-bed bioreactor utilizing microorganisms. The dilute product is concentrated and purified by utilizing distillation and/or a biparticle fluidized-bed bioreactor system. 1 fig.

  9. Low work function material development for the microminiature thermionic converter.

    SciTech Connect (OSTI)

    Zavadil, Kevin Robert; Battaile, Corbett Chandler; Marshall, Albert Christian; King, Donald Bryan; Jennison, Dwight Richard

    2004-03-01

    Thermionic energy conversion in a miniature format shows potential as a viable, high efficiency, micro to macro-scale power source. A microminiature thermionic converter (MTC) with inter-electrode spacings on the order of microns has been prototyped and evaluated at Sandia. The remaining enabling technology is the development of low work function materials and processes that can be integrated into these converters to increase power production at modest temperatures (800 - 1300 K). The electrode materials are not well understood and the electrode thermionic properties are highly sensitive to manufacturing processes. Advanced theoretical, modeling, and fabrication capabilities are required to achieve optimum performance for MTC diodes. This report describes the modeling and fabrication efforts performed to develop micro dispenser cathodes for use in the MTC.

  10. Preliminary Wave Energy Converters Extreme Load Analysis: Preprint

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

    Preliminary Wave Energy Converters Extreme Load Analysis Preprint Y-H. Yu, J. Van Rij, and M. Lawson National Renewable Energy Laboratory R. Coe Sandia National Laboratories To be presented at the 34 th International Conference on Ocean, Offshore and Arctic Engineering (OMAE 2015) St. John's, Newfoundland, Canada May 31-June 5, 2015 Conference Paper NREL/CP-5000-63677 March 2015 NOTICE The submitted manuscript has been offered by an employee of the Alliance for Sustainable Energy, LLC

  11. Catalyst for converting synthesis gas to liquid motor fuels

    DOE Patents [OSTI]

    Coughlin, Peter K.

    1986-01-01

    The addition of an inert metal component, such as gold, silver or copper, to a Fischer-Tropsch catalyst comprising cobalt enables said catalyst to convert synthesis gas to liquid motor fuels at about 240.degree.-370.degree. C. with advantageously reduced selectivity of said cobalt for methane in said conversion. The catalyst composition can advantageously include a support component, such as a molecular sieve, co-catalyst/support component or a combination of such support components.

  12. GTRI's Convert Program: Minimizing the Use of Highly Enriched Uranium |

    National Nuclear Security Administration (NNSA)

    National Nuclear Security Administration | (NNSA) GTRI's Convert Program: Minimizing the Use of Highly Enriched Uranium May 29, 2014 Mission In 2004 NNSA established the Global Threat Reduction Initiative (GTRI) in the Office of Defense Nuclear Nonproliferation to, as quickly as possible, identify, secure, remove and/or facilitate the disposition of high risk vulnerable nuclear and radiological materials around the world that pose a threat to the United States and the international

  13. Webinar Recording Available: Advanced Wave Energy Converters (WEC) Dynamics

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

    and Controls Webinar Recording Available: Advanced Wave Energy Converters (WEC) Dynamics and Controls - Sandia Energy Energy Search Icon Sandia Home Locations Contact Us Employee Locator Energy & Climate Secure & Sustainable Energy Future Stationary Power Energy Conversion Efficiency Solar Energy Wind Energy Water Power Supercritical CO2 Geothermal Natural Gas Safety, Security & Resilience of the Energy Infrastructure Energy Storage Nuclear Power & Engineering Grid

  14. Sandia, NREL Release Wave Energy Converter Modeling and Simulation Code:

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

    WEC-Sim NREL Release Wave Energy Converter Modeling and Simulation Code: WEC-Sim - Sandia Energy Energy Search Icon Sandia Home Locations Contact Us Employee Locator Energy & Climate Secure & Sustainable Energy Future Stationary Power Energy Conversion Efficiency Solar Energy Wind Energy Water Power Supercritical CO2 Geothermal Natural Gas Safety, Security & Resilience of the Energy Infrastructure Energy Storage Nuclear Power & Engineering Grid Modernization Battery Testing

  15. NREL Research Helps Convert Overabundant Methane into Useful Products |

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

    Bioenergy | NREL Research Helps Convert Overabundant Methane into Useful Products March 18, 2016 Photo of a fermentation vessel cultivating our bacteria to produce lactic acid. Using fermentation vessels such as the one pictured here, NREL researchers have discovered how to cultivate genetically engineered methanotrophic bacteria to produce lactic acid, a high-value precursor to bioplastics. Photo by Holly Smith, NREL Methane is Earth's second most abundant greenhouse gas (GHG) after carbon

  16. NREL Research Helps Convert Overabundant Methane into Useful Products -

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

    News Releases | NREL Research Helps Convert Overabundant Methane into Useful Products March 18, 2016 Photo of a fermentation vessel cultivating our bacteria to produce lactic acid. Using fermentation vessels such as the one pictured here, NREL researchers have discovered how to cultivate genetically engineered methanotrophic bacteria to produce lactic acid, a high-value precursor to bioplastics. Photo by Holly Smith, NREL Methane is Earth's second most abundant greenhouse gas (GHG) after

  17. Low current plasmatron fuel converter having enlarged volume discharges

    DOE Patents [OSTI]

    Rabinovich, Alexander; Alexeev, Nikolai; Bromberg, Leslie; Cohn, Daniel R.; Samokhin, Andrei

    2005-04-19

    A novel apparatus and method is disclosed for a plasmatron fuel converter (""plasmatron"") that efficiently uses electrical energy to produce hydrogen rich gas. The volume and shape of the plasma discharge is controlled by a fluid flow established in a plasma discharge volume. A plasmatron according to this invention produces a substantially large effective plasma discharge volume allowing for substantially greater volumetric efficiency in the initiation of chemical reactions within a volume of bulk fluid reactant flowing through the plasmatron.

  18. Low current plasmatron fuel converter having enlarged volume discharges

    DOE Patents [OSTI]

    Rabinovich, Alexander; Alexeev, Nikolai; Bromberg, Leslie; Cohn, Daniel R.; Samokhin, Andrei

    2009-10-06

    A novel apparatus and method is disclosed for a plasmatron fuel converter ("plasmatron") that efficiently uses electrical energy to produce hydrogen rich gas. The volume and shape of the plasma discharge is controlled by a fluid flow established in a plasma discharge volume. A plasmatron according to this invention produces a substantially large effective plasma discharge volume allowing for substantially greater volumetric efficiency in the initiation of chemical reactions within a volume of bulk fluid reactant flowing through the plasmatron.

  19. Advanced Wave Energy Converters (WEC) Dynamics and Controls Webinar: June

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

    6, 2016 at 2:00 p.m. EDT Wave Energy Converters (WEC) Dynamics and Controls Webinar: June 6, 2016 at 2:00 p.m. EDT - Sandia Energy Energy Search Icon Sandia Home Locations Contact Us Employee Locator Energy & Climate Secure & Sustainable Energy Future Stationary Power Energy Conversion Efficiency Solar Energy Wind Energy Water Power Supercritical CO2 Geothermal Natural Gas Safety, Security & Resilience of the Energy Infrastructure Energy Storage Nuclear Power & Engineering

  20. Successful testing of Sandia Labs' Wave Energy Converter (WEC) system

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

    Successful testing of Sandia Labs' Wave Energy Converter (WEC) system - Sandia Energy Energy Search Icon Sandia Home Locations Contact Us Employee Locator Energy & Climate Secure & Sustainable Energy Future Stationary Power Energy Conversion Efficiency Solar Energy Wind Energy Water Power Supercritical CO2 Geothermal Natural Gas Safety, Security & Resilience of the Energy Infrastructure Energy Storage Nuclear Power & Engineering Grid Modernization Battery Testing Nuclear Energy

  1. Converting sugars to sugar alcohols by aqueous phase catalytic hydrogenation

    DOE Patents [OSTI]

    Elliott, Douglas C.; Werpy, Todd A.; Wang, Yong; Frye, Jr., John G.

    2003-05-27

    The present invention provides a method of converting sugars to their corresponding sugar alcohols by catalytic hydrogenation in the aqueous phase. It has been found that surprisingly superior results can be obtained by utilizing a relatively low temperature (less than 120.degree. C.), selected hydrogenation conditions, and a hydrothermally stable catalyst. These results include excellent sugar conversion to the desired sugar alcohol, in combination with long life under hydrothermal conditions.

  2. Sandia National Laboratories Uses Its Wave Energy Converter (WEC) to

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

    Harness the Motion of the Ocean Uses Its Wave Energy Converter (WEC) to Harness the Motion of the Ocean - Sandia Energy Energy Search Icon Sandia Home Locations Contact Us Employee Locator Energy & Climate Secure & Sustainable Energy Future Stationary Power Energy Conversion Efficiency Solar Energy Wind Energy Water Power Supercritical CO2 Geothermal Natural Gas Safety, Security & Resilience of the Energy Infrastructure Energy Storage Nuclear Power & Engineering Grid

  3. Experimental testing of wave energy converter (WEC) controls

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

    testing of wave energy converter (WEC) controls - Sandia Energy Energy Search Icon Sandia Home Locations Contact Us Employee Locator Energy & Climate Secure & Sustainable Energy Future Stationary Power Energy Conversion Efficiency Solar Energy Wind Energy Water Power Supercritical CO2 Geothermal Natural Gas Safety, Security & Resilience of the Energy Infrastructure Energy Storage Nuclear Power & Engineering Grid Modernization Battery Testing Nuclear Energy Defense Waste

  4. Converting Methane to Methanol: Structural Insight into the Reaction Center

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

    of Particulate Methane Monooxygenase 3 Raquel L. Lieberman,* Amy C. Rosenzweig,* and Timothy L. Stemmler# *Depts. of Biochemistry, Molecular Biology, and Cell Biology and of Chemistry, Northwestern University, Evanston, Illinois 60208, USA #Dept. of Biochemistry and Molecular Biology, Wayne State University, School of Medicine, Detroit, Michigan 48201, USA. Methane-oxidizing bacteria (methanotrophs) are extremely attractive from a chemist's perspective because these organisms convert methane

  5. Magnetization switching in a CoFeB/MgO magnetic tunnel junction by combining spin-transfer torque and electric field-effect

    SciTech Connect (OSTI)

    Kanai, S.; Nakatani, Y.; Yamanouchi, M.; Ikeda, S.; Sato, H.; Matsukura, F.; Ohno, H.

    2014-05-26

    We propose and demonstrate a scheme for magnetization switching in magnetic tunnel junctions, in which two successive voltage pulses are applied to utilize both spin-transfer torque and electric field effect. Under this switching scheme, a CoFeB/MgO magnetic tunnel junction with perpendicular magnetic easy axis is shown to switch faster than by spin-transfer torque alone and more reliably than that by electric fields alone.

  6. Status of NASA`s Stirling Space Power Converter Program

    SciTech Connect (OSTI)

    Dudenhoefer, J.E.; Winter, J.M.

    1994-09-01

    An overview is presented of the NASA Lewis Research Center Free-Piston Stirling Space Power Converter Technology Program. This work is being conducted under NASA`s Civil Space Technology Initiative. The goal of the CSTI High Capacity Power Element is to develop the technology base needed to meet the long duration, high capacity power requirements for future NASA space initiatives. Efforts are focused upon increasing system power output and system thermal and electric energy conversion efficiency at least fivefold over current SP-100 technology, and on achieving systems that are compatible with space nuclear reactors. This paper will discuss Stirling experience in Space Power Converters. Fabrication is nearly completed for the 1050 K Component Test Power Converter (CTPC); results of motoring tests of the cold end (525 K), are presented. The success of these and future designs is dependent upon supporting research and technology efforts including heat pipes, bearings, superalloy joining technologies, high efficiency alternators, life and reliability testing and predictive methodologies. This paper provides an update of progress in some of these technologies leading off with a discussion of free-piston Stirling experience in space.

  7. Mathematical modeling of postcombustion in a KOBM converter

    SciTech Connect (OSTI)

    Gou, H.; Irons, G.A.; Lu, W.-K. )

    1993-02-01

    A mathematical model has been developed to describe gas flow, combustion reactions, and heat transfer in converter-type steelmaking processes. The k-[epsilon] two-equation turbulent model, a finite reaction model, and the DeMarco-Lockwood flux model have been incorporated in this model to deal with the turbulent flow, postcombustion reactions, and radiation heat transfer. Local gaseous flow patterns, temperature, and heat flux distributions were calculated for a 300 tonne Kloeckner Oxygen Blowing Maximillanshuette (KOBM) converter. Comparison between the heat-transfer fluxes calculated based on the model and those measured industrially indicates the validity of the model in this application. The postcombustion has been found to be determined by the decarburization rate (DCR) which is directly related to the hardness of blowing not by the entrainment of surrounding gas to the oxygen jet as previously reported. The model revealed that about 20 pct of what is normally considered to be recovered heat has actually been lost through the vessel wall and to the lance. It is shown that this model is useful in studying the detailed mechanisms of postcombustion to optimize operations in converter-type steelmaking processes.

  8. Ecological measures for converter steelmaking emphasizing process integration

    SciTech Connect (OSTI)

    Wiesinger, H.A.; Patuzzi, A.A.; Gara, S.P. )

    1994-09-01

    Integrated technological and environmental solutions have become a key challenge, particularly for the iron and steel industry. End of pipe thinking, or the approach to solve all emission-related problems solely by exp-process cleaning systems is neither a long-term economic solution nor a satisfactory environmental answer. In addition, dealing with the problem of emissions must be redirected to the source. Optimized technologies and systems must be increasingly employed which not only maximizes production and product quality, but also minimizes the overall environmental impact for converter steelmaking. This presentation focuses on state of the art technologies emphasizing process integration. Various technological alternatives for converter steelmaking are discussed in terms of best available solutions for minimized overall environmental impact. Effective implementation of ecological measures for converter steelmaking are to be achieved through total view strategies which take into account the entire production process route from raw material preparation to steelmaking, including by-product management up to the final and safe disposal of waste. Future-oriented technologies include: Airfine for integrated gas cleaning and waste management for sinter plants; Corex featuring the lowest rate of environmental emissions for the production of hot metal; LT (Lurgi-Thyssen) steel gas process for emission control, energy recovery and dust recycling in BOF vessels.

  9. Minimize Boiler Short Cycling Losses

    SciTech Connect (OSTI)

    Not Available

    2006-01-01

    This revised ITP tip sheet on minimizing boiler short cycling losses provides how-to advice for improving industrial steam systems using low-cost, proven practices and technologies.

  10. OPERATIONAL RESULTS OF THE SPALLATION NEUTRON SOURCE (SNS) POLYPHASE CONVERTER-MODULATOR FOR THE 140 KV KLYSTRON RF SYSTEMS

    SciTech Connect (OSTI)

    W.A. REASS; J.D. DOSS; ET AL

    2001-06-01

    This paper describes the first operational results of the 140 kV, 1 MW average, 11 MW peak, zero-voltage-switching, 20 kHz polyphase bridge, boost converter-modulator for klystron pulse application. The DC-DC converter derives the buss voltages from a standard 13.8 kV to 2100 Y substation cast-core transformer. Energy storage and filtering is provided by self-clearing metallized hazy polypropylene traction capacitors. Three ''H-Bridge'' Insulated Gate Bipolar Transistor (IGBT) switching networks are used to generate the polyphase 20 kHz transformer primary drive waveforms. The 20 kHz drive waveforms are chirped the appropriate duration to generate the desired klystron pulse width. Pulse-Width Modulation (PWM) of the individual 20 kHz pulses is utilized to provide regulated output waveforms with adaptive feedforward and feedback techniques. The boost transformer design utilizes amorphous nanocrystalline material that provides the required low core loss at design flux levels and switching frequencies. Resonant shunt peaking is used on the transformer secondary to boost output voltage and resonate transformer leakage inductance. With the appropriate transformer leakage inductance and peaking capacitance, zero-voltage-switching of the IGBT's is attained, minimizing switching losses. Reviews of these design parameters and an examination of the first operational results will be performed.