National Library of Energy BETA

Sample records for low pressure sodium

  1. The low-pressure sodium lamp

    SciTech Connect (OSTI)

    Hooker, J.D.

    1997-12-31

    For many years before the introduction of the sodium vapor lamp, scientists had been aware of the remarkably high luminous efficacy of the sodium discharge. However, many technical problems had to be overcome before these lamps could be marketed. The first commercial low pressure sodium lamps were introduced in the early 1930s and to this day they remain the most efficient light sources available. The high efficacy is due partly to the fact that these lamps emit nearly monochromatic yellow light, which is very close to the peak sensitivity of the human eye. Sodium lamps have come a long way since their introduction, and efficacies are now approaching 200 lumens per watt. Despite increasing competition from other types of discharge lamp, low pressure sodium lamps of the SOX type find widespread use in road and security lighting, particularly in Great Britain and many other parts of Europe. This paper reviews the operation and development of the low pressure sodium lamp, and shows what makes it different from the many other types of discharge lamp available.

  2. Synthesis of sodium polyhydrides at high pressures

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

    Struzhkin, Viktor V.; Kim, Duck Young; Stavrou, Elissaios; Muramatsu, Takaki; Mao, Ho-kwang; Pickard, Chris J.; Needs, Richard J.; Prakapenka, Vitali B.; Goncharov, Alexander F.

    2016-07-28

    Archetypal ionic NaH is the only known compound of sodium and hydrogen. Application of high pressure is known to promote states with higher atomic coordination, but extensive searches for polyhydrides with unusual stoichiometry have had only limited success in spite of several theoretical predictions. Here we report the first observation of the formation of polyhydrides of Na (NaH3 and NaH7) above 40 GPa and 2,000 K. Moreover, we combine synchrotron X-ray diffraction and Raman spectroscopy in a laser-heated diamond anvil cell and theoretical random structure searching, which both agree on the stable structures and compositions. Our results support the formationmore » of multicenter bonding in a material with unusual stoichiometry. These results are applicable to the design of new energetic solids and high-temperature superconductors based on hydrogen-rich materials.« less

  3. Low pressure hydrocyclone separator

    SciTech Connect (OSTI)

    Flanigan, D.A.; Stolhand, J.E.

    1989-07-04

    This patent describes a method of separating a dispersed phase liquid from a bulk phase liquid of a liquid-liquid mixture, the dispersed phase and bulk phase liquids having different densities. The method comprises the steps of: providing a supply of the liquid-liquid mixture at a first pressure; providing a pump means including means for minimizing degradation of the volumetric means size of droplets of the dispersed phase further including a pump size for maintaining the pump means at substantially near maximum flow rate capacity; pumping the liquid-liquid mixture with at least one pump means to a second pressure such that a differential between the first and second pressures is not substantially greater than a differential pressure at which the pump means begins to substantially degrade the volumetric mean size of droplets of the dispersed phase liquid passing therethrough, the pumping without substantial droplet degradation being achieved by operating the pump means at relatively near its maximum flow rate capacity to substantially reduce on a percentage basis the effect of fluid slippage within the pump means; directing the liquid-liquid mixture from the pump means to a hydrocyclone; and separating a substantial portion of the dispersed phase liquid from the liquid-liquid mixture in the hydrocyclone.

  4. Low temperature sodium-beta battery

    DOE Patents [OSTI]

    Farmer, Joseph C

    2013-11-19

    A battery that will operate at ambient temperature or lower includes an enclosure, a current collector within the enclosure, an anode that will operate at ambient temperature or lower within the enclosure, a cathode that will operate at ambient temperature or lower within the enclosure, and a separator and electrolyte within the enclosure between the anode and the cathode. The anode is a sodium eutectic anode that will operate at ambient temperature or lower and is made of a material that is in a liquid state at ambient temperature or lower. The cathode is a low melting ion liquid cathode that will operate at ambient temperature or lower and is made of a material that is in a liquid state at ambient temperature or lower.

  5. Low pressure carbonylation of heterocycles

    DOE Patents [OSTI]

    Coates, Geoffrey W.; Kramer, John W.; Schmidt, Joseph A. R.

    2011-01-25

    Heterocycles, e.g., epoxides, are carbonylated at low pressure with high percentage conversion to cyclic, ring expanded products using the catalyst ##STR00001## where L is tetrahydrofuran (THF).

  6. Low pressure carbonylation of heterocycles

    DOE Patents [OSTI]

    Coates, Geoffrey W.; Kramer, John

    2009-08-04

    Heterocycles, e.g., epoxides, are carbonylated at low pressure with high percentage conversion to cyclic, ring expanded products using the catalyst ##STR00001## where L is tetrahydrofuran (THF).

  7. Low-temperature Sodium-Beta Battery - Energy Innovation Portal

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

    Energy Storage Energy Storage Find More Like This Return to Search Low-temperature Sodium-Beta Battery Lawrence Livermore National Laboratory Contact LLNL About This Technology Technology Marketing Summary Rechargeable metallic sodium batteries have application in large-scale energy storage applications such as electric power generation and distribution, in motive applications such as electric vehicles, hybrids, and plug-in hybrids, and for aerospace applications such as powering satellites. So

  8. Low frequency pressure modulation of indium antimonide

    SciTech Connect (OSTI)

    Hallock, Gary A.; Meier, Mark A.

    2012-07-15

    A lumped parameter resonator capable of generating megapascal pressures at low frequency (kilohertz) is described. Accelerometers are used to determine the applied pressure, and are calibrated with a piezoelectric sample. A laser diagnostic was also developed to measure the pressure in semiconductor samples through the band gap pressure dependence. In addition, the laser diagnostic has been used to measure the attenuation coefficient {alpha} of commercially available indium antimonide (InSb) wafers. The resonator and laser diagnostic have been used with InSb samples to verify the pressure response.

  9. Low-pressure injection molding

    SciTech Connect (OSTI)

    Mangels, J.A. (Ceradyne Inc., Costa Mesa, CA (United States))

    1994-05-01

    Ceramic injection molding experienced a revival in the 1970s and 1980s with the application of ceramics for gas turbine components. Concurrently, techniques were being developed for the injection molding of powdered metal compositions into complex shaped articles. The impetus for the development of injection molding as a ceramic fabrication process lay in the potential to produce complex-shaped components to near-net shape. In the ceramic injection molding process, ceramic powders are processed to obtain the desired particle size, distribution and morphology and blended to obtain a homogeneous distribution. These powders are then mixed with the organic binders, generally in a heated, highshear mixer at temperatures above the melting point of the organic binders. The injection molding mix is pelletized, cooled and fed into an injection molding machine. The molding mix is reheated to a fluid state and injected under high pressure (7--70 MPa) into a die cavity. The molded part is removed from the tooling after the molding mix has solidified in the die. The organic binders are then removed from the component at temperatures up to 400 C, generally by some combination of wicking and thermal decomposition. Finally, the component is sintered to obtain its final ceramic properties, using conventional ceramic processes.

  10. Flash High-Pressure Condensate to Regenerate Low-Pressure Steam...

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

    2 Flash High-Pressure Condensate to Regenerate Low-Pressure Steam Low-pressure process steam requirements are usually met by throttling high- pressure steam, but a portion of the ...

  11. VACUUM SEALING MEANS FOR LOW VACUUM PRESSURES

    DOE Patents [OSTI]

    Milleron, N.

    1962-06-12

    S>A vacuum seal is designed in which the surface tension of a thin layer of liquid metal of low vapor pressure cooperates with adjacent surfaces to preclude passages of gases across pressure differentials as low as 10/sup -8/ mm Hg. Mating contiguous surfaces composed of copper, brass, stainless steel, nickel, molybdenum, tungsten, tantalum, glass, quartz, and/or synthetic mica are disposed to provide a maximum tolerance, D, expressed by 2 gamma /P/sub 1/, where gamma is the coefflcient of the surface tension of the metal sealant selected in dynes/cm/sub 2/. Means for heating the surfaces remotely is provided where temperatures drop below about 250 deg C. A sealant consisting of an alloy of gallium, indium, and tin, among other combinations tabulated, is disposed therebetween after treating the surfaces to improve wettability, as by ultrasonic vibrations, the surfaces and sealants being selected according to the anticipated experimental conditions of use. (AEC)

  12. Flash High-Pressure Condensate to Regenerate Low-Pressure Steam...

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

    Use Steam Jet Ejectors or Thermocompressors to Reduce Venting of Low-Pressure Steam Consider Installing High-Pressure Boilers with Backpressure Turbine-Generators Use Vapor ...

  13. Alternative Strategies for Low Pressure End Uses | Department of Energy

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

    Alternative Strategies for Low Pressure End Uses Alternative Strategies for Low Pressure End Uses This tip sheet outlines alternative strategies for low-pressure end uses as a pathway to reduced compressed air energy costs. COMPRESSED AIR TIP SHEET #11 Alternative Strategies for Low Pressure End Uses (August 2004) (246.6 KB) More Documents & Publications Eliminate Inappropriate Uses of Compressed Air Compressed Air System Control Strategies Engineer End Uses for Maximum Efficiency

  14. Low energy high pressure miniature screw valve

    DOE Patents [OSTI]

    Fischer, Gary J.; Spletzer, Barry L.

    2006-12-12

    A low energy high pressure screw valve having a valve body having an upper portion and a lower portion, said lower portion of said valve body defining an inlet flow passage and an outlet flow passage traversing said valve body to a valve seat, said upper portion of said valve body defining a cavity at said valve seat, a diaphragm restricting flow between said upper portion of said valve body and said lower portion, said diaphragm capable of engaging said valve seat to restrict fluid communication between said inlet passage and said outlet passage, a plunger within said cavity supporting said diaphragm, said plunger being capable of engaging said diaphragm with said valve seat at said inlet and outlet fluid passages, said plunger being in point contact with a drive screw having threads engaged with opposing threads within said upper portion of said valve body such engagement allowing motion of said drive screw within said valve body.

  15. Use Vapor Recompression to Recover Low-Pressure Waste Steam

    Broader source: Energy.gov [DOE]

    This tip sheet on recovering low-pressure waste steam provides how-to advice for improving industrial steam systems using low-cost, proven practices and technologies.

  16. How low can you go? Low pressure drop laboratory design

    SciTech Connect (OSTI)

    Weale, John; Rumsey, Peter; Sartor, Dale; Lock, Lee Eng

    2001-12-01

    Laboratory buildings are characterized by the production of potentially hazardous fumes within the occupied space. The primary objective of a laboratory ventilation system is to isolate and protect the occupants from the fumes, as well as provide minimum outside air at a comfortable temperature. Fume removal results in the need for a large volume of conditioned make-up air, typically a significantly greater volume than required for space temperature conditioning purposes. The high quantity of exhaust naturally results in a once through system, which is also often required by codes that prohibit any recirculation in a laboratory space. The high costs associated with high airflow systems are magnified by the 24 hours a day, 356 days a year ventilation operation often seen in laboratory situations. All too often, the common design approach taken to laboratory mechanical systems results in a traditional office ventilation system upsized to meet a laboratory's requirements. Recognizing the unique aspects of laboratory requirements and operation is essential to optimizing the mechanical system. Figure 1 shows a breakdown of a laboratory building's electricity use, based on a DOE 2 model of a baseline laboratory building design for Montana State University (Bozeman, MT). In laboratory buildings, the largest and easiest target for energy use reduction is usually the ventilation energy. At about 50 percent of the buildings total electricity usage, a 15 percent reduction in the power required by the ventilation system would save more energy than eliminating all lighting energy. As the largest component of a laboratory's energy consumption, the ventilation system is the first target to reduce the energy bill. Significantly improving the standard design efficiency of a ventilation system requires a lower air pressure drop system on both the supply and exhaust system. Implementing low-pressure drop design strategies from the early stages of the design process will result in

  17. Collection, transmission of low-pressure Sichuan gas detailed

    SciTech Connect (OSTI)

    Runcang, C.

    1983-09-28

    As a result of fairly long-term exploitation, the gas fields in the Sichuan Basin which were opened quite early now have reduced output and lower wellhead pressures. The wellhead pressure in some gas wells is now lower than the pressure of the collection and transmission pipelines. The technologies for collecting and transmitting low-pressure gas in gas fields are discussed.

  18. Low Temperature Sodium-Sulfur Grid Storage and EV Battery - Energy

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

    Innovation Portal Vehicles and Fuels Vehicles and Fuels Energy Storage Energy Storage Electricity Transmission Electricity Transmission Advanced Materials Advanced Materials Find More Like This Return to Search Low Temperature Sodium-Sulfur Grid Storage and EV Battery Lawrence Berkeley National Laboratory Contact LBL About This Technology Technology Marketing Summary Berkeley Lab researcher Gao Liu has developed an innovative design for a battery, made primarily of sodium and sulfur, that

  19. Solubilities of ethane in aqueous solutions of sodium dodecyl sulfate at elevated pressures

    SciTech Connect (OSTI)

    Li, P.; Han, B.; Yan, H.; Liu, R.

    1995-10-01

    The solubilities of ethane in aqueous solutions of sodium dodecyl sulfate (SDS) were measured at 313.15 K and at pressures up to 3 MPa. The molalities of SDS (m{sub SDS}) in the aqueous solution were 0.0000, 0.0020, 0.0040, 0.0060, 0.0070, 0.0080, 0.0090, 0.0100, 0.0126, 0.0150, 0.0200, and 0.0300. The effect of SDS on the gas solubility in both concentration regions below and above the critical micelle concentration (cmc) was studied. The existence of the micelles of SDS in the solution is favorable to the dissolution of ethane due to the hydrocarbon-like interior of the micelles. The solubilities of ethane in each micelle at different pressures were evaluated based on some assumptions. It was found that the intramicellar solubility of ethane is less than that of the gas in n-dodecane. It was also found that the solubility of ethane in the micelles increases linearly with the partial pressure of ethane. The cmc of SDS was evaluated based on the solubility vs m{sub SDS} curves and the effect of dissolved ethane on the cmc was studied. It was observed that the cmc shifts toward a higher value with the increase in dissolved ethane.

  20. Engine having a high pressure hydraulic system and low pressure lubricating system

    DOE Patents [OSTI]

    Bartley, Bradley E.; Blass, James R.; Gibson, Dennis H.

    2000-01-01

    An engine includes a high pressure hydraulic system having a high pressure pump and at least one hydraulically-actuated device attached to an engine housing. A low pressure engine lubricating system is attached to the engine housing and includes a circulation conduit fluidly connected to an outlet from the high pressure pump.

  1. Low pressure cooling seal system for a gas turbine engine

    SciTech Connect (OSTI)

    Marra, John J

    2014-04-01

    A low pressure cooling system for a turbine engine for directing cooling fluids at low pressure, such as at ambient pressure, through at least one cooling fluid supply channel and into a cooling fluid mixing chamber positioned immediately downstream from a row of turbine blades extending radially outward from a rotor assembly to prevent ingestion of hot gases into internal aspects of the rotor assembly. The low pressure cooling system may also include at least one bleed channel that may extend through the rotor assembly and exhaust cooling fluids into the cooling fluid mixing chamber to seal a gap between rotational turbine blades and a downstream, stationary turbine component. Use of ambient pressure cooling fluids by the low pressure cooling system results in tremendous efficiencies by eliminating the need for pressurized cooling fluids for sealing this gap.

  2. Synthesis of YBCO Superconductors Using Low-Pressure Processing...

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

    Transmission Electricity Transmission Find More Like This Return to Search Synthesis of YBCO Superconductors Using Low-Pressure Processing Brookhaven National Laboratory...

  3. Low tritium partial pressure permeation system for mass transport...

    Office of Scientific and Technical Information (OSTI)

    Low tritium partial pressure permeation system for mass transport measurement in lead lithium eutectic Citation Details In-Document Search This content will become publicly ...

  4. Low-Cost Fiber Optic Pressure Sensor

    DOE Patents [OSTI]

    Sheem, Sang K. (Pleasanton, CA)

    2004-05-18

    The size and cost of fabricating fiber optic pressure sensors is reduced by fabricating the membrane of the sensor in a non-planar shape. The design of the sensors may be made in such a way that the non-planar membrane becomes a part of an air-tight cavity, so as to make the membrane resilient due to the air-cushion effect of the air-tight cavity. Such non-planar membranes are easier to make and attach.

  5. Low-Cost Fiber Optic Pressure Sensor

    DOE Patents [OSTI]

    Sheem, Sang K. (Pleasanton, CA)

    2003-07-22

    The size and cost of fabricating fiber optic pressure sensors is reduced by fabricating the membrane of the sensor in a non-planar shape. The design of the sensors may be made in such a way that the non-planar membrane becomes a part of an air-tight cavity, so as to make the membrane resilient due to the air-cushion effect of the air-tight cavity. Such non-planar membranes are easier to make and attach.

  6. Flash High-Pressure Condensate to Regenerate Low-Pressure - Steam Tip Sheet #12

    SciTech Connect (OSTI)

    2012-01-31

    This revised AMO tip sheet on regenerating low-pressure steam provides how-to advice for improving industrial steam systems using low-cost, proven practices and technologies.

  7. Proton conducting sodium alginate electrolyte laterally coupled low-voltage oxide-based transistors

    SciTech Connect (OSTI)

    Liu, Yang Hui; Wan, Qing; Qiang Zhu, Li; Shi, Yi

    2014-03-31

    Solution-processed sodium alginate electrolyte film shows a high proton conductivity of ?5.5??10{sup ?3} S/cm and a high lateral electric-double-layer (EDL) capacitance of ?2.0??F/cm{sup 2} at room temperature with a relative humidity of 57%. Low-voltage in-plane-gate indium-zinc-oxide-based EDL transistors laterally gated by sodium alginate electrolytes are fabricated on glass substrates. The field-effect mobility, current ON/OFF ratio, and subthreshold swing of such EDL transistors are estimated to be 4.2 cm{sup 2} V{sup ?1} s{sup ?1}, 2.8??10{sup 6}, and 130?mV/decade, respectively. At last, a low-voltage driven resistor-load inverter is also demonstrated. Such in-plane-gate EDL transistors have potential applications in portable electronics and low-cost biosensors.

  8. Method of gettering hydrogen under conditions of low pressure

    DOE Patents [OSTI]

    Mendelsohn, M.H.; Gruen, D.M.

    1983-08-09

    A ternary intermetallic compound having the formula Zr(V[sub 1[minus]x]Cr[sub x])[sub 2] where x is in the range of 0.01 to 0.90 is capable of reversibly sorbing hydrogen at temperatures ranging from room temperature to 200 C, at pressures down to 10[sup [minus]6] Torr. The compound is suitable for use as a hydrogen getter in low pressure, high temperature applications such as magnetic confinement fusion devices. 3 figs.

  9. Method of gettering hydrogen under conditions of low pressure

    DOE Patents [OSTI]

    Mendelsohn, Marshall H.; Gruen, Dieter M.

    1983-01-01

    A ternary intermetallic compound having the formula Zr(V.sub.1-x Cr.sub.x).sub.2 where x is in the range of 0.01 to 0.90 is capable of reversibly sorbing hydrogen at temperatures ranging from room temperature to 200.degree. C., at pressures down to 10.sup.-6 Torr. The compound is suitable for use as a hydrogen getter in low pressure, high temperature applications such as magnetic confinement fusion devices.

  10. THE ABSORPTION OF HYDROGEN ON LOW PRESSURE HYDRIDE MATERIALS

    SciTech Connect (OSTI)

    Morgan, G.; Korinko, P.

    2012-04-03

    For this study, hydrogen getter materials (Zircaloy-4 and pure zirconium) that have a high affinity for hydrogen (and low overpressure) have been investigated to determine the hydrogen equilibrium pressure on Zircaloy-4 and pure zirconium. These materials, as with most getter materials, offered significant challenges to overcome given the low hydrogen equilibrium pressure for the temperature range of interest. Hydrogen-zirconium data exists for pure zirconium at 500 C and the corresponding hydrogen overpressure is roughly 0.01 torr. This manuscript presents the results of the equilibrium pressures for the absorption and desorption of hydrogen on zirconium materials at temperatures ranging from 400 C to 600 C. The equilibrium pressures in this temperature region range from 150 mtorr at 600 C to less than 0.1 mtorr at 400 C. It has been shown that the Zircaloy-4 and zirconium samples are extremely prone to surface oxidation prior to and during heating. This oxidation precludes the hydrogen uptake, and therefore samples must be heated under a minimum vacuum of 5 x 10{sup -6} torr. In addition, the Zircaloy-4 samples should be heated at a sufficiently low rate to maintain the system pressure below 0.5 mtorr since an increase in pressure above 0.5 mtorr could possibly hinder the H{sub 2} absorption kinetics due to surface contamination. The results of this study and the details of the testing protocol will be discussed.

  11. Low pressure high speed Stirling air engine. Final technical report

    SciTech Connect (OSTI)

    Ross, M.A.

    1980-06-16

    The purpose of this project was to design, construct and test a simple, appropriate technology low pressure, high speed, wood-fired Stirling air engine of 100 W output. The final design was a concentric piston/displacer engine of 454 in. bore and 1 in. stroke with a rhombic drive mechanism. The project engine was ultimately completed and tested, using a propane burner for all tests as a matter of convenience. The 100 W aim was exceeded, at atmospheric pressure, over a wide range of engine speed with the maximum power being 112 W at 1150 rpm. A pressure can was constructed to permit pressurization; however the grant funds were running out, and the only pressurized power test attempted was unsuccessful due to seal difficulties. This was a disappointment because numerous tests on the 4 cubic inch engine suggested power would be more than doubled with pressurization at 25 psig. A manifold was designed and constructed to permit operation of the engine over a standard No. 40 pot bellied stove. The engine was run successfully, but at reduced speed and power, over this stove. The project engine started out being rather noisy in operation, but modifications ultimately resulted in a very quiet engine. Various other difficulties and their solutions also are discussed. (LCL)

  12. Single-ring magnetic cusp low gas pressure ion source

    DOE Patents [OSTI]

    Bacon, Frank M.; Brainard, John P.; O'Hagan, James B.; Walko, Robert J.

    1985-01-01

    A single-ring magnetic cusp low gas pressure ion source designed for use in a sealed, nonpumped neutron generator utilizes a cathode and an anode, three electrically floating electrodes (a reflector behind the cathode, a heat shield around the anode, and an aperture plate), together with a single ring-cusp magnetic field, to establish and energy-filtering mechanism for producing atomic-hydrogen ions.

  13. Microlaminate composite structures by low pressure plasma spray deposition

    SciTech Connect (OSTI)

    Castro, R.G.; Stanek, P.W.

    1988-01-01

    The low pressure plasma spray (LPPS) process has been utilized in the development and fabrication of metal/metal, metal/carbide, and metal/oxide composite structures; including particulate dispersion and both continuous and discontinuous laminates. This report describes the LPPS process and the development of copper/tungsten microlaminate structures utilizing this processing method. Microstructures and mechanical properties of the Cu/W composites are compared to conventionally produced constituent material properties. 4 refs., 6 figs., 2 tabs.

  14. LOW-PRESSURE MEMBRANE CONTACTORS FOR CARBON DIOXIDE CAPTURE

    SciTech Connect (OSTI)

    Baker, Richard; Kniep, Jay; Hao, Pingjiao; Chan, Chi Cheng; Nguyen, Vincent; Huang, Ivy; Amo, Karl; Freeman, Brice; Fulton, Don; Ly, Jennifer; Lipscomb, Glenn; Lou, Yuecun; Gogar, Ravikumar

    2014-09-30

    This final technical progress report describes work conducted by Membrane Technology and Research, Inc. (MTR) for the Department of Energy (DOE NETL) on development of low-pressure membrane contactors for carbon dioxide (CO2) capture from power plant flue gas (award number DE-FE0007553). The work was conducted from October 1, 2011 through September 30, 2014. The overall goal of this three-year project was to build and operate a prototype 500 m2 low-pressure sweep membrane module specifically designed to separate CO2 from coal-fired power plant flue gas. MTR was assisted in this project by a research group at the University of Toledo, which contributed to the computational fluid dynamics (CFD) analysis of module design and process simulation. This report details the work conducted to develop a new type of membrane contactor specifically designed for the high-gas-flow, low-pressure, countercurrent sweep operation required for affordable membrane-based CO2 capture at coal power plants. Work for this project included module development and testing, design and assembly of a large membrane module test unit at MTR, CFD comparative analysis of cross-flow, countercurrent, and novel partial-countercurrent sweep membrane module designs, CFD analysis of membrane spacers, design and fabrication of a 500 m2 membrane module skid for field tests, a detailed performance and cost analysis of the MTR CO2 capture process with low-pressure sweep modules, and a process design analysis of a membrane-hybrid separation process for CO2 removal from coal-fired flue gas. Key results for each major task are discussed in the report.

  15. Low pressure stagnation flow reactor with a flow barrier

    DOE Patents [OSTI]

    Vosen, Steven R.

    2001-01-01

    A flow barrier disposed at the periphery of a workpiece for achieving uniform reaction across the surface of the workpiece, such as a semiconductor wafer, in a stagnation flow reactor operating under the conditions of a low pressure or low flow rate. The flow barrier is preferably in the shape of annulus and can include within the annular structure passages or flow channels for directing a secondary flow of gas substantially at the surface of a semiconductor workpiece. The flow barrier can be constructed of any material which is chemically inert to reactive gases flowing over the surface of the semiconductor workpiece.

  16. Performance of Low Smeared Density Sodium-cooled Fast Reactor Metal Fuel

    SciTech Connect (OSTI)

    Porter, D. L.; H. J. M. Chichester; Medvedev, P. G.; Hayes, S. L.; Teague, M. C.

    2015-10-01

    An experiment was performed in the Experimental Breeder Rector-II (EBR-II) in the 1990s to show that metallic fast reactor fuel could be used in reactors with a single, once-through core. To prove the long duration, high burnup, high neutron exposure capability an experiment where the fuel pin was designed with a very large fission gas plenum and very low fuel smeared density (SD). The experiment, X496, operated to only 8.3 at. % burnup because the EBR-II reactor was scheduled for shut-down at that time. Many of the examinations of the fuel pins only funded recently with the resurgence of reactor designs using very high-burnup fuel. The results showed that, despite the low smeared density of 59% the fuel swelled radially to contact the cladding, fission gas release appeared to be slightly higher than demonstrated in conventional 75%SD fuel tests and axial growth was about the same as 75% SD fuel. There were axial positions in some of the fuel pins which showed evidence of fuel restructuring and an absence of fission products with low metaling points and gaseous precursors (Cs and Rb). A model to investigate whether these areas may have overheated due to a loss of bond sodium indicates that it is a possible explanation for the fuel restructuring and something to be considered for fuel performance modeling of low SD fuel.

  17. Performance of low smeared density sodium-cooled fast reactor metal fuel

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

    Porter, D. L.; H. J. M. Chichester; Medvedev, P. G.; Hayes, S. L.; Teague, M. C.

    2015-06-17

    An experiment was performed in the Experimental Breeder Rector-II (EBR-II) in the 1990s to show that metallic fast reactor fuel could be used in reactors with a single, once-through core. To prove the long duration, high burnup, high neutron exposure capability an experiment where the fuel pin was designed with a very large fission gas plenum and very low fuel smeared density (SD). The experiment, X496, operated to only 8.3 at. % burnup because the EBR-II reactor was scheduled for shut-down at that time. Many of the examinations of the fuel pins only funded recently with the resurgence of reactormore » designs using very high-burnup fuel. The results showed that, despite the low smeared density of 59% the fuel swelled radially to contact the cladding, fission gas release appeared to be slightly higher than demonstrated in conventional 75%SD fuel tests and axial growth was about the same as 75% SD fuel. There were axial positions in some of the fuel pins which showed evidence of fuel restructuring and an absence of fission products with low metaling points and gaseous precursors (Cs and Rb). Lastly, a model to investigate whether these areas may have overheated due to a loss of bond sodium indicates that it is a possible explanation for the fuel restructuring and something to be considered for fuel performance modeling of low SD fuel.« less

  18. Performance of low smeared density sodium-cooled fast reactor metal fuel

    SciTech Connect (OSTI)

    Porter, D. L.; H. J. M. Chichester; Medvedev, P. G.; Hayes, S. L.; Teague, M. C.

    2015-06-17

    An experiment was performed in the Experimental Breeder Rector-II (EBR-II) in the 1990s to show that metallic fast reactor fuel could be used in reactors with a single, once-through core. To prove the long duration, high burnup, high neutron exposure capability an experiment where the fuel pin was designed with a very large fission gas plenum and very low fuel smeared density (SD). The experiment, X496, operated to only 8.3 at. % burnup because the EBR-II reactor was scheduled for shut-down at that time. Many of the examinations of the fuel pins only funded recently with the resurgence of reactor designs using very high-burnup fuel. The results showed that, despite the low smeared density of 59% the fuel swelled radially to contact the cladding, fission gas release appeared to be slightly higher than demonstrated in conventional 75%SD fuel tests and axial growth was about the same as 75% SD fuel. There were axial positions in some of the fuel pins which showed evidence of fuel restructuring and an absence of fission products with low metaling points and gaseous precursors (Cs and Rb). Lastly, a model to investigate whether these areas may have overheated due to a loss of bond sodium indicates that it is a possible explanation for the fuel restructuring and something to be considered for fuel performance modeling of low SD fuel.

  19. Wetting of Sodium on ??-Al2O3/YSZ Composites for Low Temperature Planar Sodium-Metal Halide Batteries

    SciTech Connect (OSTI)

    Reed, David M.; Coffey, Greg W.; Mast, Eric S.; Canfield, Nathan L.; Mansurov, Jirgal; Lu, Xiaochuan; Sprenkle, Vincent L.

    2013-04-01

    Wetting of Na on B-Al2O3/YSZ composites was investigated using the sessile drop technique. The effects of moisture and surface preparation were studied at low temperatures. Electrical conductivity of Na/B-Al2O3-YSZ/Na cells was also investigated at low temperatures and correlated to the wetting behavior. The use of planar B-Al2O3 substrates at low temperature with low cost polymeric seals is realized due to improved wetting at low temperature and conductivity values consistent with the literature.

  20. Photocatalyst activation in a pulsed low pressure discharge

    SciTech Connect (OSTI)

    Rousseau, A.; Guaitella, O.; Gatilova, L.; Thevenet, F.; Guillard, C.; Roepcke, J.; Stancu, G.D.

    2005-11-28

    The effect of combining plasma and photocatalyst for Volatile Organic Compounds (VOC) removal was investigated in a pulsed low-pressure dc discharge. The photocatalyst was TiO{sub 2} while the VOC was acetylene (1000 ppm) diluted in dry air. The temporal evolution of C{sub 2}H{sub 2} concentration was measured by Tunable Diode Laser Absorption Spectroscopy (TDLAS) in the mid-infrared region during the plasma pulse (one second). The contribution of external ultraviolet radiation and plasma exposure were quantified, both with and without a photocatalyst. The synergetic effect was clearly demonstrated.

  1. Downhole steam generator using low pressure fuel and air supply

    DOE Patents [OSTI]

    Fox, Ronald L.

    1983-01-01

    An apparatus for generation of steam in a borehole for penetration into an earth formation wherein a spiral, tubular heat exchanger is used in the combustion chamber to isolate the combustion process from the water being superheated for conversion into steam. The isolation allows combustion of a relatively low pressure oxidant and fuel mixture for generating high enthalpy steam. The fuel is preheated by feedback of combustion gases from the top of the combustion chamber through a fuel preheater chamber. The hot exhaust gases of combustion at the bottom of the combustion chamber, after flowing over the heat exchanger enter an exhaust passage and pipe. The exhaust pipe is mounted inside the water supply line heating the water flowing into the heat exchanger. After being superheated in the heat exchanger, the water is ejected through an expansion nozzle and converts into steam prior to penetration into the earth formation. Pressure responsive doors are provided at a steam outlet downstream of the nozzle and close when the steam pressure is lost due to flameout.

  2. Thermodynamic analysis of cascade microcryocoolers with low pressure ratios

    SciTech Connect (OSTI)

    Radebaugh, Ray

    2014-01-29

    The vapor-compression cycle for refrigeration near ambient temperature achieves high efficiency because the isenthalpic expansion of the condensed liquid is a rather efficient process. However, temperatures are limited to about 200 K with a single-stage system. Temperatures down to 77 K are possible with many stages. In the case of microcryocoolers using microcompressors, pressure ratios are usually limited to about 6 or less. As a result, even more stages are required to reach 77 K. If the microcompressors can be fabricated with low-cost wafer-level techniques, then the use of many stages with separate compressors may become a viable option for achieving temperatures of 77 K with high efficiency. We analyze the ideal thermodynamic efficiency of a cascade Joule-Thomson system for various temperatures down to 77 K and with low pressure ratios. About nine stages are required for 77 K, but fewer stages are also analyzed for operation at higher temperatures. For 77 K, an ideal second-law efficiency of 83 % of Carnot is possible with perfect recuperative heat exchangers and 65 % of Carnot is possible with no recuperative heat exchangers. The results are compared with calculated efficiencies in mixed-refrigerant cryocoolers over the range of 77 K to 200 K. Refrigeration at intermediate temperatures is also available. The use of single-component fluids in each of the stages is expected to eliminate the problem of pulsating flow and temperature oscillations experienced in microcryocoolers using mixed refrigerants.

  3. Very low pressure high power impulse triggered magnetron sputtering

    SciTech Connect (OSTI)

    Anders, Andre; Andersson, Joakim

    2013-10-29

    A method and apparatus are described for very low pressure high powered magnetron sputtering of a coating onto a substrate. By the method of this invention, both substrate and coating target material are placed into an evacuable chamber, and the chamber pumped to vacuum. Thereafter a series of high impulse voltage pulses are applied to the target. Nearly simultaneously with each pulse, in one embodiment, a small cathodic arc source of the same material as the target is pulsed, triggering a plasma plume proximate to the surface of the target to thereby initiate the magnetron sputtering process. In another embodiment the plasma plume is generated using a pulsed laser aimed to strike an ablation target material positioned near the magnetron target surface.

  4. High pressure, high current, low inductance, high reliability sealed terminals

    DOE Patents [OSTI]

    Hsu, John S [Oak Ridge, TN; McKeever, John W [Oak Ridge, TN

    2010-03-23

    The invention is a terminal assembly having a casing with at least one delivery tapered-cone conductor and at least one return tapered-cone conductor routed there-through. The delivery and return tapered-cone conductors are electrically isolated from each other and positioned in the annuluses of ordered concentric cones at an off-normal angle. The tapered cone conductor service can be AC phase conductors and DC link conductors. The center core has at least one service conduit of gate signal leads, diagnostic signal wires, and refrigerant tubing routed there-through. A seal material is in direct contact with the casing inner surface, the tapered-cone conductors, and the service conduits thereby hermetically filling the interstitial space in the casing interior core and center core. The assembly provides simultaneous high-current, high-pressure, low-inductance, and high-reliability service.

  5. Correlation between sodium sulfate mass transfer and low-temperature hot corrosion

    SciTech Connect (OSTI)

    Ahluwalia, R.K.; Im, K.H. )

    1988-01-01

    A mass transfer model is developed that considers diffusive and chemical aspects of sodium sulfate formation and deposition on cooled blades of coal-fired gas turbines. The roles of gas phase condensation of sodium sulfate and multicomponent diffusion across a chemically frozen thin boundary layer are elaborated. A rational procedure is presented for correlating material wastage with laboratory weight gain data obtained by exposing alloy specimens precoated with a thin film of salt to SO{sub 2}-SO{sub 3} in an oxygen environment. The sodium sulfate mass transfer model is used in conjunction with the correlation to project blade corrosion and lifetime as a function of gas turbine inlet temperature, blade cooling, and sodium and sulfur contaminant concentration.

  6. METHOD FOR PUMPING GASES AT LOW VACUUM PRESSURES

    DOE Patents [OSTI]

    Milleron, N.

    1962-06-01

    A method is given for pumping overpressure "pulses" or "bursts" of gases without a significant rise in base pressure within a "gettering-type" vacuum pump having surfaces within the pumping cavity coated with or comprising clean gettering metal, e.g., Mo or Ta. The cavity is first pumped down by any convenient means to an equilibrium base pressure in the range desired, generally below 10/sup -6/ mm Hg. At this pressure, the metal immediately adsorbs overpressures or "bursts" of gases striking same with thermal motion without raising the base pressure significantiy. Desorption takes place at an equilibrium rate which, of course, is dependent upon the equilibrium pressure, and such desorbed gases are continuously removed by diffuaion pump or other pumping, whereby said overpressures or "bursts" of gases are removed without a rise in the equilibrium pressure and/or back diffusion of the gaseous pulse from the pumping cavity. (AEC)

  7. Alternative Strategies for Low-Pressure End Uses; Industrial...

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

    1 * August 2004 Industrial Technologies Program Suggested Actions * Review the compressed air applications to determine which ones are valid high-pressure and which ones can ...

  8. Low Cost, High Efficiency, High Pressure Hydrogen Storage

    SciTech Connect (OSTI)

    Mark Leavitt

    2010-03-31

    A technical and design evaluation was carried out to meet DOE hydrogen fuel targets for 2010. These targets consisted of a system gravimetric capacity of 2.0 kWh/kg, a system volumetric capacity of 1.5 kWh/L and a system cost of $4/kWh. In compressed hydrogen storage systems, the vast majority of the weight and volume is associated with the hydrogen storage tank. In order to meet gravimetric targets for compressed hydrogen tanks, 10,000 psi carbon resin composites were used to provide the high strength required as well as low weight. For the 10,000 psi tanks, carbon fiber is the largest portion of their cost. Quantum Technologies is a tier one hydrogen system supplier for automotive companies around the world. Over the course of the program Quantum focused on development of technology to allow the compressed hydrogen storage tank to meet DOE goals. At the start of the program in 2004 Quantum was supplying systems with a specific energy of 1.1-1.6 kWh/kg, a volumetric capacity of 1.3 kWh/L and a cost of $73/kWh. Based on the inequities between DOE targets and Quantum’s then current capabilities, focus was placed first on cost reduction and second on weight reduction. Both of these were to be accomplished without reduction of the fuel system’s performance or reliability. Three distinct areas were investigated; optimization of composite structures, development of “smart tanks” that could monitor health of tank thus allowing for lower design safety factor, and the development of “Cool Fuel” technology to allow higher density gas to be stored, thus allowing smaller/lower pressure tanks that would hold the required fuel supply. The second phase of the project deals with three additional distinct tasks focusing on composite structure optimization, liner optimization, and metal.

  9. Exhaust Aftertreatment and Low Pressure Loop EGR Applied to an...

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

    05 Diesel Engine Emissions Reduction (DEER) Conference Presentations and Posters PDF icon ... Particulate Filter Technology for Low-Temperature and Low-NOxPM Applications Update on ...

  10. Use Vapor Recompression to Recover Low-Pressure Waste Steam (Revised0

    SciTech Connect (OSTI)

    Not Available

    2008-03-01

    This revised ITP tip sheet on recovering low-pressure waste steam provides how-to advice for improving industrial steam systems using low-cost, proven practices and technologies.

  11. Use Vapor Recompression to Recover Low-Pressure Waste - Steam Tip Sheet #11

    SciTech Connect (OSTI)

    2012-01-31

    This revised AMO tip sheet on recovering low-pressure waste steam provides how-to advice for improving industrial steam systems using low-cost, proven practices and technologies.

  12. Low Temperature Irradiation Embrittlement of Reactor Pressure Vessel Steels

    SciTech Connect (OSTI)

    Wang, Jy-An John

    2015-08-01

    The embrittlement trend curve development project for HFIR reactor pressure vessel (RPV) steels was carried out with three major tasks. Which are (1) data collection to match that used in HFIR steel embrittlement trend published in 1994 Journal Nuclear Material by Remec et. al, (2) new embrittlement data of A212B steel that are not included in earlier HFIR RPV trend curve, and (3) the adjustment of nil-ductility-transition temperature (NDTT) shift data with the consideration of the irradiation temperature effect. An updated HFIR RPV steel embrittlement trend curve was developed, as described below. NDTT( C) = 23.85 log(x) + 203.3 log (x) + 434.7, with 2- uncertainty of 34.6 C, where parameter x is referred to total dpa. The developed update HFIR RPV embrittlement trend curve has higher embrittlement rate compared to that of the trend curve developed in 1994.

  13. Exhaust Aftertreatment and Low Pressure Loop EGR Applied to an Off-Highway

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

    Engine | Department of Energy Aftertreatment and Low Pressure Loop EGR Applied to an Off-Highway Engine Exhaust Aftertreatment and Low Pressure Loop EGR Applied to an Off-Highway Engine 2005 Diesel Engine Emissions Reduction (DEER) Conference Presentations and Posters 2005_deer_baumgard.pdf (277.94 KB) More Documents & Publications Full Useful Life (120,000 miles) Exhaust Emission Performance of a NOx Adsorber and Diesel Particle Filter Equipped Passenger Car and Medium-Duty Engine in

  14. Low pressure EGR system having full range capability

    DOE Patents [OSTI]

    Easley, Jr. William Lanier; Milam, David Michael; Roozenboom, Stephan Donald; Bond, Michael Steven; Kapic, Amir

    2009-09-22

    An exhaust treatment system for an engine is disclosed and may have an air induction circuit, an exhaust circuit, and an exhaust recirculation circuit. The air induction circuit may be configured to direct air into the engine. The exhaust circuit may be configured to direct exhaust from the engine and include a turbine driven by the exhaust, a particulate filter disposed in series with and downstream of the turbine, and a catalytic device disposed in series with and downstream of the particulate filter. The exhaust recirculation circuit may be configured to selectively redirect at least some of the exhaust from between the particulate filter and the catalytic device to the air induction circuit. The catalytic device is selected to create backpressure within the exhaust circuit sufficient to ensure that, under normal engine operating conditions above low idle, exhaust can flow into the air induction circuit without throttling of the air.

  15. THE EFFECT OF 3HE ON LOW PRESSURE HYDRIDE ABSORPTION MEASUREMENTS WITH TRITIUM

    SciTech Connect (OSTI)

    Staack, G.; Klein, J.

    2011-01-20

    Absorption isotherm data exists for a wide variety of hydrogen-metal systems. When working with high purity gases, appropriately sized equipment, and hydrides with equilibrium pressures above several hundred Pa, data collection is relatively straightforward. Special consideration must be given to experiments involving low equilibrium pressure hydrides, as even sub-ppm levels of gas impurities can generate partial pressures many times greater than the equilibrium pressures to be measured. Tritium absorption experiments are further complicated by the continuous generation of helium-3. The time required to transfer and absorb a known quantity of tritium onto a sample ultimately limits the minimum pressure range that can be studied using the standard technique. Equations are presented which show the pressure of helium-3 in a sample cell based on the amount of tritium to be absorbed, the sample cell volume and temperature, and the decay time of tritium. Sample calculations for zirconium show that at 300 C, the estimated helium-3 pressure in the cell will be equal to the hydrogen absorption pressure after only milliseconds of tritium decay. An alternate method is presented that permits the collection of equilibrium data at pressures orders of magnitude lower than possible using a direct approach.

  16. Nuclear resonant inelastic X-ray scattering at high pressure and low temperature

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

    Bi, Wenli; Zhao, Jiyong; Lin, Jung -Fu; Jia, Quanjie; Hu, Michael Y.; Jin, Changqing; Ferry, Richard; Yang, Wenge; Struzhkin, Viktor; Alp, E. Ercan

    2015-01-01

    In this study, a new synchrotron radiation experimental capability of coupling nuclear resonant inelastic X-ray scattering with the cryogenically cooled high-pressure diamond anvil cell technique is presented. The new technique permits measurements of phonon density of states at low temperature and high pressure simultaneously, and can be applied to studies of phonon contribution to pressure- and temperature-induced magnetic, superconducting and metal–insulator transitions in resonant isotope-bearing materials. In this report, a pnictide sample, EuFe2As2, is used as an example to demonstrate this new capability at beamline 3-ID of the Advanced Photon Source, Argonne National Laboratory. A detailed description of the technicalmore » development is given. The Fe-specific phonon density of states and magnetism from the Fe sublattice in Eu57Fe2As2 at high pressure and low temperature were derived by using this new capability.« less

  17. Downhole steam generator using low-pressure fuel and air supply

    DOE Patents [OSTI]

    Fox, R.L.

    1981-01-07

    For tertiary oil recovery, an apparatus for downhole steam generation is designed in which water is not injected directly onto the flame in the combustor, the combustion process is isolated from the reservoir pressure, the fuel and oxidant are supplied to the combustor at relatively low pressures, and the hot exhaust gases is prevented from entering the earth formation but is used to preheat the fuel and oxidant and water. The combustion process is isolated from the steam generation process. (DLC)

  18. Low pressure electrospray ionization system and process for effective transmission of ions

    DOE Patents [OSTI]

    Tang, Keqi; Page, Jason S; Kelly, Ryan T; Smith, Richard D

    2012-05-08

    Systems and methods that provide up to complete transmission of ions between coupled stages with low effective ion losses. An "interfaceless" electrospray ionization system is further described that operates an electrospray at a reduced pressure such that standard electrospray sample solutions can be directly sprayed into an electrodynamic ion funnel which provides ion focusing and transmission of ions into a mass analyzer. Furthermore, chambers maintained at different pressures can allow for more optimal operating conditions for an electrospray emitter and an ion guide.

  19. Impact Of Sodium Oxalate, Sodium Aluminosilicate, and Gibbsite/Boehmite on ARP Filter Performance

    SciTech Connect (OSTI)

    Poirier, M.; Burket, P.

    2015-11-01

    The Savannah River Site (SRS) is currently treating radioactive liquid waste with the Actinide Removal Process (ARP) and the Modular Caustic Side Solvent Extraction Unit (MCU). Recently, the low filter flux through the ARP of approximately 5 gallons per minute has limited the rate at which radioactive liquid waste can be treated. Salt Batch 6 had a lower processing rate and required frequent filter cleaning. Savannah River Remediation (SRR) has a desire to understand the causes of the low filter flux and to increase ARP/MCU throughput. SRR requested SRNL to conduct bench-scale filter tests to evaluate whether sodium oxalate, sodium aluminosilicate, or aluminum solids (i.e., gibbsite and boehmite) could be the cause of excessive fouling of the crossflow or secondary filter at ARP. The authors conducted the tests by preparing slurries containing 6.6 M sodium Salt Batch 6 supernate, 2.5 g MST/L slurry, and varying concentrations of sodium oxalate, sodium aluminosilicate, and aluminum solids, processing the slurry through a bench-scale filter unit that contains a crossflow primary filter and a dead-end secondary filter, and measuring filter flux and transmembrane pressure as a function of time. Among the conclusions drwn from this work are the following: (1) All of the tests showed some evidence of fouling the secondary filter. This fouling could be from fine particles passing through the crossflow filter. (2) The sodium oxalate-containing feeds behaved differently from the sodium aluminosilicate- and gibbsite/boehmite-containing feeds.

  20. β-NaVOPO4 obtained by a low-temperature synthesis process: A new 3.3 V cathode for sodium-ion batteries

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

    He, Guang; Huq, Ashfia; Manthiram, Arumugam; Kan, Wang Hay

    2016-02-02

    Vanadyl phosphates (VOPO4) represent a class of attractive cathodes in lithium-ion batteries. However, the exploration of this type of materials in sodium-ion batteries is rare. Here, we report for the first time the synthesis of orthorhombic β-NaVOPO4 by first chemically extracting lithium from beta-LiVOPO4 and then inserting sodium into the obtained β-VOPO4 by a microwave-assisted solvothermal process with NaI, which serves both as a reducing agent and sodium source. Intermediate NaxVOPO4 compositions with x = 0.3, 0.5, and 0.8 have also been obtained by controlling the amount of NaI in the reaction mixture. Joint Rietveld refinement of synchrotron X-ray diffractionmore » (XRD) and neutron diffraction confirms that the fully sodiated β-NaVOPO4 is isostructural with the lithium counterpart β-LiVOPO4. Bond valence sum maps suggest that sodium ions possibly diffuse along the [010] direction in the lattice, similar to the ionic conduction pathway in β-LiVOPO4. Although the initial discharge capacity is low due to the protons in the structure, it steadily increases with cycling with a long plateau at 3.3 V. As a result, ex situ XRD data of cycled β-VOPO4 and β-NaVOPO4 electrodes confirm the reversible reaction in sodium cells involving the V4+/V5+ redox couple.« less

  1. Liquid-Metal Electrode to Enable Ultra-Low Temperature Sodium-Beta Alumina Batteries for Renewable Energy Storage

    SciTech Connect (OSTI)

    Lu, Xiaochuan; Li, Guosheng; Kim, Jin Yong; Mei, Donghai; Lemmon, John P.; Sprenkle, Vincent L.; Liu, Jun

    2014-08-01

    Metal electrodes have a high capacity for energy storage but have found limited applications in batteries because of dendrite formation and other problems. In this paper, we report a new alloying strategy that can significantly reduce the melting temperature and improve wetting with the electrolyte to allow the use of liquid metal as anode in sodium-beta alumina batteries (NBBs) at much lower temperatures (e.g., 95 to 175°C). Commercial NBBs such as sodium-sulfur (Na-S) battery and sodium-metal halide (ZEBRA) batteries typically operate at relatively high temperatures (e.g., 300-350°C) due to poor wettability of sodium on the surface of β"-Al2O3. Our combined experimental and computational studies suggest that Na-Cs alloy can replace pure sodium as the anode material, which provides a significant improvement in wettability, particularly at lower temperatures (i.e., <200°C). Single cells with the Na-Cs alloy anode exhibit excellent cycling life over those with pure sodium anode at 175 and 150°C. The cells can even operate at 95°C, which is below the melting temperature of pure sodium. These results demonstrate that NBB can be operated at ultra lower temperatures with successfully solving the wetting issue. This work also suggests a new strategy to use liquid metal as the electrode materials for advanced batteries that can avoid the intrinsic safety issues associated with dendrite formation on the anode.

  2. Simulation of an Ar/NH{sub 3} low pressure magnetized direct current discharge

    SciTech Connect (OSTI)

    Li Zhi [School of Science, University of Science and Technology Liaoning, Anshan 114051 (China); School of Physics and Optoelectronic Engineering, Dalian University of Technology, Dalian 116024 (China); Zhao Zhen [School of Chemistry and Life Science, Anshan Normal University, Anshan 114007 (China); School of Chemical Engineering, University of Science and Technology Liaoning, Anshan 114051 (China); Li Xuehui [Physiccal Science and Technical College, Dalian University, Dalian 116622 (China)

    2013-01-15

    A two-dimensional fluid model has been used to investigate the properties of plasma in an Ar/NH{sub 3} low pressure magnetized direct current discharge. We compared the simulation results with the theoretical and experimental results of the other gas discharge in which the magnetic field is considered. Results that obtained using this method are in good agreement with literature. The simulation results show that the positive ammonia ion density follows the positive argon ion density. The Ar{sub 2}{sup +} density is slightly higher than the Ar{sup +} density at 100 mTorr. The largest ammonia ion is NH{sub 3}{sup +} ion, followed by NH{sub 2}{sup +}, NH{sub 4}{sup +}, and NH{sup +} ions. The contribution of NH{sup +} ions to the density of the positive ammonia ions is marginal. The influence of pressure on the plasma discharge has been studied by simulation, and the mechanisms have been discussed. The average plasma density increases as pressure increased. The plasma density appears to be more inhomogeneous than that at the lower pressure. The ratio of charge particles changed as pressure increased. The Ar{sup +} density is slightly higher than the Ar{sub 2}{sup +} density as the pressure increased. It makes NH{sub 4}{sup +} ratio increase as pressure increased. It shows that the electron temperature drops with rising pressure by numerical calculation.

  3. Studies on hydrogen plasma and dust charging in low-pressure filament discharge

    SciTech Connect (OSTI)

    Kakati, B. Kalita, D.; Kausik, S. S.; Saikia, B. K.; Bandyopadhyay, M.

    2014-08-15

    The effect of working gas pressure and dust charging on electron energy probability function has been studied for hydrogen plasma in a multi-dipole dusty plasma device. A cylindrical Langmuir probe is used to evaluate the plasma parameters and electron energy probability function (EEPF) for different working pressures. For lower energy range (below 10?eV), the EEPF follows a bi-Maxwellian shape at very low pressure (6 10{sup ?5}?mbar), while elevating the working pressure up to ?2 10{sup ?3} mbar, the shape of the EEPF transforms into a single Maxwellian. Some dip structures are observed at high energy range (??>?10?eV) in the EEPF of hydrogen plasma at all the working conditions. In presence of dust particles, it is observed that the shape of the EEPF changes due to the redistribution of the high and low-energy electron populations. Finally, the effect of working pressure on charge accumulation on dust particles is studied with the help of a Faraday cup and electrometer. From the observations, a strong influence of working pressure on plasma parameters, EEPF and dust charging is observed.

  4. Heat pump employing optimal refrigerant compressor for low pressure ratio applications

    DOE Patents [OSTI]

    Ecker, Amir L.

    1982-01-01

    What is disclosed is a heat pump apparatus for conditioning a fluid characterized by a fluid handler for circulating the fluid in heat exchange relationship with a refrigerant fluid; two refrigerant heat exchangers; one for effecting the heat exchange with the fluid and a second refrigerant-heat exchange fluid heat exchanger for effecting a low pressure ratio of compression of the refrigerant; a rotary compressor for compressing the refrigerant with low power consumption at the low pressure ratio; at least one throttling valve connecting at the inlet side of heat exchanger in which liquid refrigerant is vaporized; a refrigerant circuit serially connecting the above elements; refrigerant in the circuit; a source of heat exchange fluid; heat exchange fluid circulating device and heat exchange fluid circuit for circulating the heat exchange fluid in heat exchange relationship with the refrigerant.

  5. In-Reactor Oxidation of Zircaloy-4 Under Low Water Vapor Pressures

    SciTech Connect (OSTI)

    Luscher, Walter G.; Senor, David J.; Clayton, Kevin; Longhurst, Glen

    2015-01-01

    Complementary in- and ex-reactor oxidation tests have been performed to evaluate the oxidation and hydrogen absorption performance of Zircaloy-4 (Zr-4) under relatively low partial pressures (300 and 1000 Pa) of water vapor at specified test temperatures (330 and 370C). Data from these tests will be used to support fabrication of components intended for isotope-producing targets and provide information regarding the temperature and pressure dependence of oxidation and hydrogen absorption of Zr-4 over the specified range of test conditions. Comparisons between in- and ex- reactor test results were performed to evaluate the influence of irradiation.

  6. In-reactor oxidation of zircaloy-4 under low water vapor pressures

    SciTech Connect (OSTI)

    Luscher, Walter G.; Senor, David J.; Clayton, Kevin K.; Longhurst, Glen R.

    2015-01-01

    Complementary in- and ex-reactor oxidation tests have been performed to evaluate the oxidation and hydrogen absorption performance of Zircaloy-4 (Zr-4) under relatively low partial pressures (300 and 1000 Pa) of water vapor at specified test temperatures (330 and 370 C). Data from these tests will be used to support the fabrication of components intended for isotope-producing targets and provide information regarding the temperature and pressure dependence of oxidation and hydrogen absorption of Zr- 4 over the specified range of test conditions. Comparisons between in- and ex-reactor test results were performed to evaluate the influence of irradiation.

  7. In-Situ Method for Treating Residual Sodium

    DOE Patents [OSTI]

    Sherman, Steven R.; Henslee, S. Paul

    2005-07-19

    A unique process for deactivating residual sodium in Liquid Metal Fast Breeder Reactor (LMFBR) systems which uses humidified (but not saturated) carbon dioxide at ambient temperature and pressure to convert residual sodium into solid sodium bicarbonate.

  8. In-situ method for treating residual sodium

    DOE Patents [OSTI]

    Sherman, Steven R. (Idaho Falls, ID); Henslee, S. Paul (Idaho Falls, ID)

    2005-07-19

    A unique process for deactivating residual sodium in Liquid Metal Fast Breeder Reactor (LMFBR) systems which uses humidified (but not saturated) carbon dioxide at ambient temperature and pressure to convert residual sodium into solid sodium bicarbonate.

  9. Hugoniot Measurements at Low Pressures in Tin Using 800 MeV proton Radiography

    SciTech Connect (OSTI)

    Schwartz, Cynthia; Hogan, Gary E; King, Nicholas S. P.; Kwiathowski, Kris K.; Mariam, Fesseha G.; Marr-Lyon, Mark; McNeil, Wendy Vogan; Merrill, Frank E.; Morris, Christopher; Rightley, Paul; Saunders, Alexander

    2009-08-05

    A 2cm long 8 mm diameter cylindrical tin target has been shocked to a pressure in the region of the {beta} {yields} {gamma} phase change using a small, low density PETN charge mounted on the opposite side of a stainless steel diaphragm. The density jump and shock velocity were measured radiographically as the shock wave moved through the sample and the pressure dropped, using the proton radiography facility at LANL. This provided a quasi-continuous record of the equations of state along the Hugoniot for the P1 wave from a shock velocity of 3.25 km/sec down to near the sound speed. Edge release effects were removed from the data using tomographic techniques. The data show evidence for a phase transition that extends over a broad pressure range. The data and analysis will be presented.

  10. Highly ionized physical vapor deposition plasma source working at very low pressure

    SciTech Connect (OSTI)

    Stranak, V.; Herrendorf, A.-P.; Drache, S.; Hippler, R.; Cada, M.; Hubicka, Z.; Tichy, M.

    2012-04-02

    Highly ionized discharge for physical vapor deposition at very low pressure is presented in the paper. The discharge is generated by electron cyclotron wave resonance (ECWR) which assists with ignition of high power impulse magnetron sputtering (HiPIMS) discharge. The magnetron gun (with Ti target) was built into the single-turn coil RF electrode of the ECWR facility. ECWR assistance provides pre-ionization effect which allows significant reduction of pressure during HiPIMS operation down to p = 0.05 Pa; this is nearly more than an order of magnitude lower than at typical pressure ranges of HiPIMS discharges. We can confirm that nearly all sputtered particles are ionized (only Ti{sup +} and Ti{sup ++} peaks are observed in the mass scan spectra). This corresponds well with high plasma density n{sub e} {approx} 10{sup 18} m{sup -3}, measured during the HiPIMS pulse.

  11. Instantaneous and efficient surface wave excitation of a low pressure gas or gases

    DOE Patents [OSTI]

    Levy, Donald J.; Berman, Samuel M.

    1988-01-01

    A system for instantaneously ionizing and continuously delivering energy in the form of surface waves to a low pressure gas or mixture of low pressure gases, comprising a source of rf energy, a discharge container, (such as a fluorescent lamp discharge tube), an rf shield, and a coupling device responsive to rf energy from the source to couple rf energy directly and efficiently to the gas or mixture of gases to ionize at least a portion of the gas or gases and to provide energy to the gas or gases in the form of surface waves. The majority of the rf power is transferred to the gas or gases near the inner surface of the discharge container to efficiently transfer rf energy as excitation energy for at least one of the gases. The most important use of the invention is to provide more efficient fluorescent and/or ultraviolet lamps.

  12. MELCOR calculations for a low-pressure short-term station blackout in a BWR-6

    SciTech Connect (OSTI)

    Carbajo, J.J. [Martin Marietta Energy Systems, Oak Ridge, TN (United States)

    1995-12-31

    A postulated, low-pressure, short term station blackout severe accident has been analyzed using the MELCOR code for the Grand Gulf nuclear power plant. Different versions have been used with three different models of the plant. This paper presents results of the effects of different plant models and versions of MELCOR on the calculated results and to present the best-estimating timing of events for this transient.

  13. Low pressure arc discharge lamp apparatus with magnetic field generating means

    DOE Patents [OSTI]

    Grossman, Mark W.; George, William A.; Maya, Jakob

    1987-01-01

    A low-pressure arc discharge apparatus having a magnetic field generating means for increasing the output of a discharge lamp is disclosed. The magnetic field generating means, which in one embodiment includes a plurality of permanent magnets, is disposed along the lamp for applying a constant transverse magnetic field over at least a portion of the positive discharge column produced in the arc discharge lamp operating at an ambient temperature greater than about 25.degree. C.

  14. Low pressure arc discharge lamp apparatus with magnetic field generating means

    DOE Patents [OSTI]

    Grossman, M.W.; George, W.A.; Maya, J.

    1987-10-06

    A low-pressure arc discharge apparatus having a magnetic field generating means for increasing the output of a discharge lamp is disclosed. The magnetic field generating means, which in one embodiment includes a plurality of permanent magnets, is disposed along the lamp for applying a constant transverse magnetic field over at least a portion of the positive discharge column produced in the arc discharge lamp operating at an ambient temperature greater than about 25 C. 3 figs.

  15. Low pressure electrospray ionization system and process for effective transmission of ions

    DOE Patents [OSTI]

    Tang, Keqi; Page, Jason S.; Kelly, Ryan T.; Smith, Richard D.

    2010-03-02

    A system and method are disclosed that provide up to complete transmission of ions between coupled stages with low effective ion losses. A novel "interfaceless" electrospray ionization system is further described that operates the electrospray at a reduced pressure such that standard electrospray sample solutions can be directly sprayed into an electrodynamic ion funnel which provides ion focusing and transmission of ions into a mass analyzer.

  16. Tritium Behavior in Lead Lithium Eutectic (LLE) at Low Tritium Partial Pressure

    Office of Environmental Management (EM)

    Behavior in Lead Lithium Eutectic (LLE) at Low Tritium Partial Pressure 33 rd Tritium Focus Group meeting, Savannah River National Laboratory, SC Masashi Shimada, Ph.D. Fusion Safety Program, Idaho National Laboratory, STIMS # INL/MS-14-31893| Savannah River National Laboratory, SC | April 25, 2014 Outlines 1. Motivation 2. Experimental apparatus 3. TMAP modeling 4. Experimental results 5. Modeling results 6. Future work M.Shimada | Tritium Focus Group meeting | SRNL, SC | April 25, 2014 2

  17. Simplified configuration for the combustor of an oil burner using a low pressure, high flow air-atomizing nozzle

    DOE Patents [OSTI]

    Butcher, Thomas A.; Celebi, Yusuf; Fisher, Leonard

    2000-09-15

    The invention relates to clean burning of fuel oil with air. More specifically, to a fuel burning combustion head using a low-pressure, high air flow atomizing nozzle so that there will be a complete combustion of oil resulting in a minimum emission of pollutants. The improved fuel burner uses a low pressure air atomizing nozzle that does not result in the use of additional compressors or the introduction of pressurized gases downstream, nor does it require a complex design. Inventors:

  18. Study of flow fields induced by surface dielectric barrier discharge actuator in low-pressure air

    SciTech Connect (OSTI)

    Che, Xueke E-mail: st@mail.iee.ac.cn; Nie, Wansheng; Tian, Xihui; Hou, Zhiyong; He, Haobo; Zhou, Penghui; Zhou, Siyin; Yang, Chao; Shao, Tao E-mail: st@mail.iee.ac.cn

    2014-04-15

    Surface dielectric barrier discharge (SDBD) is a promising method for a flow control. Flow fields induced by a SDBD actuator driven by the ac voltage in static air at low pressures varying from 1.0 to 27.7?kPa are measured by the particle image velocimetry method. The influence of the applied ac voltage frequency and magnitude on the induced flow fields is studied. The results show that three different classes of flow fields (wall jet flow field, complex flow field, and vortex-shape flow field) can be induced by the SDBD actuator in the low-pressure air. Among them, the wall jet flow field is the same as the tangential jet at atmospheric pressure, which is, together with the vertical jet, the complex flow field. The vortex-shape flow field is composed of one vertical jet which points towards the wall and two opposite tangential jets. The complex and the vortex-shape flow fields can be transformed to the wall jet flow field when the applied ac voltage frequency and magnitude are changed. It is found that the discharge power consumption increases initially, decreases, and then increases again at the same applied ac voltage magnitude when the air pressure decreases. The tangential velocity of the wall jet flow field increases when the air pressure decreases. It is however opposite for the complex flow field. The variation of the applied ac voltage frequency influences differently three different flow fields. When the applied ac voltage magnitude increases at the same applied ac voltage frequency, the maximal jet velocity increases, while the power efficiency increases only initially and then decreases again. The discharge power shows either linear or exponential dependences on the applied ac voltage magnitude.

  19. Sodium sulfur battery seal

    DOE Patents [OSTI]

    Mikkor, Mati

    1981-01-01

    This disclosure is directed to an improvement in a sodium sulfur battery construction in which a seal between various battery compartments is made by a structure in which a soft metal seal member is held in a sealing position by holding structure. A pressure applying structure is used to apply pressure on the soft metal seal member when it is being held in sealing relationship to a surface of a container member of the sodium sulfur battery by the holding structure. The improvement comprises including a thin, well-adhered, soft metal layer on the surface of the container member of the sodium sulfur battery to which the soft metal seal member is to be bonded.

  20. Thermodynamics of methane adsorption on copper HKUST-1 at low pressure

    SciTech Connect (OSTI)

    Wu, Di; Guo, Xiaofeng; Sun, Hui; Navrotsky, Alexandra

    2015-06-11

    Metalorganic frameworks (MOFs) can be engineered as natural gas storage materials by tuning the pore structures and surface properties. Here we report the direct measurement of CH? adsorption enthalpy on a paddlewheel MOF (Cu HKUST-1) using gas adsorption calorimetry at 25 C at low pressures (below 1 bar). In this pressure region, the CH?CH? intermolecular interactions are minimized and the energetics solely reflects the CH?MOF interactions. Our results suggest moderately exothermic physisorption with an enthalpy of -21.1 1.1 kJ/mol CH? independent of coverage. The calorimetric investigation complements previous computational and crystallographic studies by providing zero coverage enthalpies of CH? adsorption. The analysis of the new and literature data suggests that in initial stages of adsorption the CH?HKUST-1 interaction tends to be more sensitive to the pore dimension than to the guest polarizability, suggesting a less specific chemical binding role for the open Cu site.

  1. HUGONIOT MEASUREMENTS AT LOW PRESSURES IN TIN USING 800 MeV PROTON RADIOGRAPHY

    SciTech Connect (OSTI)

    Schwartz, C. L.; Hogan, G. E.; King, N. S. P.; Kwiatkowski, K.; Mariam, F. G.; Merrill, F. E.; Morris, C. L.; Saunders, A.; Marr-Lyon, M.; Rightley, P. M.; McNeil, W. V.

    2009-12-28

    A 20 mm long 8 mm diameter cylindrical tin target has been shocked to a pressure just below the beta->gamma phase change, using a small, low density PETN charge mounted on the opposite side of a thin stainless steel diaphragm. The density jump and shock velocity were measured radiographically at multiple points as the shock wave moved though the sample and the pressure dropped, using the proton radiography facility at LANL. This provided a quasi-continuous record along the principal Hugoniot from a peak shock velocity of 3.27 km/sec to a minimum of 3.09 km/sec. Edge release effects were removed from the data using simple tomographic reconstruction techniques. The data and analysis are presented.

  2. The effects of plasma inhomogeneity on the nanoparticle coating in a low pressure plasma reactor

    SciTech Connect (OSTI)

    Pourali, N.; Foroutan, G.

    2015-10-15

    A self-consistent model is used to study the surface coating of a collection of charged nanoparticles trapped in the sheath region of a low pressure plasma reactor. The model consists of multi-fluid plasma sheath module, including nanoparticle dynamics, as well as the surface deposition and particle heating modules. The simulation results show that the mean particle radius increases with time and the nanoparticle size distribution is broadened. The mean radius is a linear function of time, while the variance exhibits a quadratic dependence. The broadening in size distribution is attributed to the spatial inhomogeneity of the deposition rate which in turn depends on the plasma inhomogeneity. The spatial inhomogeneity of the ions has strong impact on the broadening of the size distribution, as the ions contribute both in the nanoparticle charging and in direct film deposition. The distribution width also increases with increasing of the pressure, gas temperature, and the ambient temperature gradient.

  3. Particle modelling of magnetically confined oxygen plasma in low pressure radio frequency discharge

    SciTech Connect (OSTI)

    Benyoucef, Djilali; Yousfi, Mohammed

    2015-01-15

    The main objective of this paper is the modelling and simulation of a radio frequency (RF) discharge in oxygen at low pressure and at room temperature, including the effect of crossed electric and magnetic fields for generation and confinement of oxygen plasma. The particle model takes into account one axial dimension along the electric field axis and three velocity components during the Monte Carlo treatment of the collisions between charged particles and background gas. The simulation by this developed code allows us not only to determine the electrodynamics characteristics of the RF discharge, but also to obtain kinetics and energetic description of reactive oxygen plasma at low pressure. These information are very important for the control of the deep reactive-ion etching technology of the silicon to manufacture capacitors with high density and for the deposition thick insulating films or thick metal to manufacture micro-coils. The simulation conditions are as follows: RF peak voltage of 200 V, frequency of 13.56 MHz, crossed magnetic field varying from 0 to 50 Gauss, and oxygen pressure of 13.8 Pa. In the presence of magnetic field, the results show an increase of the plasma density, a decrease of the electron mean energy, and also a reduction of the ratio between electron density and positive ion density. Finally in order to validate, the results are successfully compared with measurements already carried out in the literature. The conditions of comparison are from 100 to 300 V of the peak voltage at 13.56 MHz under a pressure of 13.8 Pa and a gap distance of 2.5 cm.

  4. Weak interactions between water and clathrate-forming gases at low pressures

    SciTech Connect (OSTI)

    Thürmer, Konrad; Yuan, Chunqing; Kimmel, Greg A.; Kay, Bruce D.; Smith, R. Scott

    2015-07-17

    Using scanning probe microscopy and temperature programed desorption we examined the interaction between water and two common clathrate-forming gases, methane and isobutane, at low temperature and low pressure. Water co-deposited with up to 10–1 mbar methane or 10–5 mbar isobutane at 140 K onto a Pt(111) substrate yielded pure crystalline ice, i.e., the exposure to up to ~ 107 gas molecules for each deposited water molecule did not have any detectable effect on the growing films. Exposing metastable, less than 2 molecular layers thick, water films to 10–5 mbar methane does not alter their morphology, suggesting that the presence of the Pt(111) surface is not a strong driver for hydrate formation. This weak water–gas interaction at low pressures is supported by our thermal desorption measurements from amorphous solid water and crystalline ice where 1 ML of methane desorbs near ~ 43 K and isobutane desorbs near ~ 100 K. As a result, similar desorption temperatures were observed for desorption from amorphous solid water.

  5. Ductile phase toughening of molybdenum disilicide by low pressure plasma spraying

    SciTech Connect (OSTI)

    Castro, R.G.; Rollett, A.D.; Stanek, P.W. ); Smith, R.W. . Dept. of Materials Engineering)

    1992-01-01

    The low fracture toughness of MoSi{sub 2} at ambient temperature has prompted investigations into new processing methods in order to impart some degree of fracture toughness into this inherently brittle material. In the following investigation, low pressure plasma spraying was employed as a fabricating technique to produce spray-formed deposits of MoSi{sub 2} and ductile reinforced MoSi{sub 2} composites containing approximately 10 and 20 volume percent of a discontinuous tantalum lamelli reinforcement. Fracture toughness (K{sub 1C}) measurements of MoSi{sub 2} and the MoSi{sub 2}/Ta composites were done using a chevron notched 4-point bend fracture toughness test in both the as-sprayed condition and after hot isostatic pressing at 1200{degrees}C/206 MPa for 1 hour. Results from the ductile reinforced MoSi{sub 2}/Ta composites have shown fracture toughness increases on the order of 200% over the as-sprayed MoSi{sub 2}. In addition, a marked anisotropy in fracture toughness was observed in the spray-formed deposits due to the layered splat structure produced by the low pressure plasma spray process.

  6. Ductile phase toughening of molybdenum disilicide by low pressure plasma spraying

    SciTech Connect (OSTI)

    Castro, R.G.; Rollett, A.D.; Stanek, P.W.; Smith, R.W.

    1992-02-01

    The low fracture toughness of MoSi{sub 2} at ambient temperature has prompted investigations into new processing methods in order to impart some degree of fracture toughness into this inherently brittle material. In the following investigation, low pressure plasma spraying was employed as a fabricating technique to produce spray-formed deposits of MoSi{sub 2} and ductile reinforced MoSi{sub 2} composites containing approximately 10 and 20 volume percent of a discontinuous tantalum lamelli reinforcement. Fracture toughness (K{sub 1C}) measurements of MoSi{sub 2} and the MoSi{sub 2}/Ta composites were done using a chevron notched 4-point bend fracture toughness test in both the as-sprayed condition and after hot isostatic pressing at 1200{degrees}C/206 MPa for 1 hour. Results from the ductile reinforced MoSi{sub 2}/Ta composites have shown fracture toughness increases on the order of 200% over the as-sprayed MoSi{sub 2}. In addition, a marked anisotropy in fracture toughness was observed in the spray-formed deposits due to the layered splat structure produced by the low pressure plasma spray process.

  7. Weak interactions between water and clathrate-forming gases at low pressures

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

    Thürmer, Konrad; Yuan, Chunqing; Kimmel, Greg A.; Kay, Bruce D.; Smith, R. Scott

    2015-07-17

    Using scanning probe microscopy and temperature programed desorption we examined the interaction between water and two common clathrate-forming gases, methane and isobutane, at low temperature and low pressure. Water co-deposited with up to 10–1 mbar methane or 10–5 mbar isobutane at 140 K onto a Pt(111) substrate yielded pure crystalline ice, i.e., the exposure to up to ~ 107 gas molecules for each deposited water molecule did not have any detectable effect on the growing films. Exposing metastable, less than 2 molecular layers thick, water films to 10–5 mbar methane does not alter their morphology, suggesting that the presence ofmore » the Pt(111) surface is not a strong driver for hydrate formation. This weak water–gas interaction at low pressures is supported by our thermal desorption measurements from amorphous solid water and crystalline ice where 1 ML of methane desorbs near ~ 43 K and isobutane desorbs near ~ 100 K. As a result, similar desorption temperatures were observed for desorption from amorphous solid water.« less

  8. Weak interactions between water and clathrate-forming gases at low pressures

    SciTech Connect (OSTI)

    Thurmer, Konrad; Yuan, Chunqing; Kimmel, Gregory A.; Kay, Bruce D.; Smith, R. Scott

    2015-11-01

    Using scanning probe microscopy and temperature programed desorption we examined the interaction between water and two common clathrate-forming gases, methane and isobutane, at low temperature and low pressure. Water co-deposited with up to 10-1 mbar methane or 10-5 mbar isobutane at 140 K onto a Pt(111) substrate yielded pure crystalline ice, i.e., the exposure to up to ~107 gas molecules for each deposited water molecule did not have any detectable effect on the growing films. Exposing metastable, less than 2 molecular layers thick, water films to 10-5 mbar methane does not alter their morphology, suggesting that the presence of the Pt(111) surface is not a strong driver for hydrate formation. This weak water-gas interaction at low pressures is supported by our thermal desorption measurements from amorphous solid water and crystalline ice where 1 ML of methane desorbs near ~43 K and isobutane desorbs near ~100 K. Similar desorption temperatures were observed for desorption from amorphous solid water.

  9. A laser and molecular beam mass spectrometer study of low-pressure dimethyl ether flames

    SciTech Connect (OSTI)

    Andrew McIlroy; Toby D. Hain; Hope A. Michelsen; Terrill A. Cool

    2000-12-15

    The oxidation of dimethyl ether (DME) is studied in low-pressure flames using new molecular beam mass spectrometer and laser diagnostics. Two 30.0-Torr, premixed DME/oxygen/argon flames are investigated with stoichiometries of 0.98 and 1.20. The height above burner profiles of nine stable species and two radicals are measured. These results are compared to the detailed chemical reaction mechanism of Curran and coworkers. Generally good agreement is found between the model and data. The largest discrepancies are found for the methyl radical profiles where the model predicts qualitatively different trends in the methyl concentration with stoichiometry than observed in the experiment.

  10. Determination of the Electron Temperature in a Low Pressure Dusty Radiofrequency Methane Plasma

    SciTech Connect (OSTI)

    Massereau-Guilbaud, Veronique; Geraud-Grenier, Isabelle; Plain, Andre

    2011-11-29

    The particles are obtained by PECVD in radiofrequency (13.56 MHz) low pressure plasmas (90%CH4-10%Ar). During the particle growth, the particles trap electrons and modify the EEDF, and the electrical and optical characteristics of the plasma. The plasma is analyzed by Optical Emission Spectroscopy. The excitation temperature and the electron temperature are calculated from the H{sub {alpha}}, H{sub {beta}}, H{sub {gamma}} Balmer hydrogen line intensities and from Ar ones. The temporal evolutions of the temperatures during the particle formation are compared and discussed.

  11. Association of low-level blood lead and blood pressure in NHANES 1999-2006

    SciTech Connect (OSTI)

    Scinicariello, Franco; Abadin, Henry G.; Edward Murray, H.

    2011-11-15

    This study investigated whether low blood-lead levels ({<=}10 {mu}g/dL) were associated with blood pressure (BP) outcomes. The authors analyzed data from National Health and Nutrition Examination Survey 1999-2006 and participants aged 20 years or older. Outcome variables were systolic and diastolic BP measurements, pulse pressure, and hypertension status. Multivariable linear and logistic regressions stratified by race/ethnicity and gender were performed. Blood lead levels (BLL) were significantly correlated with higher systolic BP among black men and women, but not white or Mexican-American participants. BLLs were significantly associated with higher diastolic BPs among white men and women and black men, whereas, a negative association was observed in Mexican-American men that had, also, a wider pulse pressure. Black men in the 90th percentile of blood lead distribution (BLL{>=}3.50 {mu}g/dL) compared to black men in the 10th percentile of blood lead distribution (BLL{<=}0.7 {mu}g/dL) had a significant increase of risk of having hypertension (adjusted POR=2.69; 95% CI: 1.08-6.72). In addition, blood cadmium was significantly associated with hypertension and systolic and diastolic blood. This study found that, despite the continuous decline in blood lead in the U.S. population, lead exposure disparities among race and gender still exist.

  12. Effect of confining wall potential on charged collimated dust beam in low-pressure plasma

    SciTech Connect (OSTI)

    Kausik, S. S.; Kakati, B.; Saikia, B. K. [Centre of Plasma Physics, Institute for Plasma Research, Sonapur 782 402 (India)] [Centre of Plasma Physics, Institute for Plasma Research, Sonapur 782 402 (India)

    2013-05-15

    The effect of confining wall potential on charged collimated dust beam in low-pressure plasma has been studied in a dusty plasma experimental setup by applying electrostatic field to each channel of a multicusp magnetic cage. Argon plasma is produced by hot cathode discharge method at a pressure of 510{sup ?4} millibars and is confined by a full line cusped magnetic field confinement system. Silver dust grains are produced by gas-evaporation technique and move upward in the form of a collimated dust beam due to differential pressure maintained between the dust and plasma chambers. The charged grains in the beam after coming out from the plasma column enter into the diagnostic chamber and are deflected by a dc field applied across a pair of deflector plates at different confining potentials. Both from the amount of deflection and the floating potential, the number of charges collected by the dust grains is calculated. Furthermore, the collimated dust beam strikes the Faraday cup, which is placed above the deflector plates, and the current (?pA) so produced is measured by an electrometer at different confining potentials. The experimental results demonstrate the significant effect of confining wall potential on charging of dust grains.

  13. Electrical studies and plasma characterization of an atmospheric pressure plasma jet operated at low frequency

    SciTech Connect (OSTI)

    Giuliani, L.; Xaubet, M.; Grondona, D.; Minotti, F.; Kelly, H.

    2013-06-15

    Low-temperature, high-pressure plasma jets have an extensive use in medical and biological applications. Much work has been devoted to study these applications while comparatively fewer studies appear to be directed to the discharge itself. In this work, in order to better understand the kind of electrical discharge and the plasma states existing in those devices, a study of the electrical characteristics of a typical plasma jet, operated at atmospheric pressure, using either air or argon, is reported. It is found that the experimentally determined electrical characteristics are consistent with the model of a thermal arc discharge, with a highly collisional cathode sheet. The only exception is the case of argon at the smallest electrode separation studied, around 1 mm in which case the discharge is better modeled as either a non-thermal arc or a high-pressure glow. Also, variations of the electrical behavior at different gas flow rates are interpreted, consistently with the arc model, in terms of the development of fluid turbulence in the external jet.

  14. Three-electrode low pressure discharge apparatus and method for uniform ionization of gaseous media

    DOE Patents [OSTI]

    McLellan, Edward J.

    1983-01-01

    Uniform, transverse electrical discharges are produced in gaseous media without the necessity of switching the main discharge voltage with an external device which carries the entire discharge current. A three-electrode low pressure discharge tube is charged across its anode (1) and cathode (2) to below breakdown voltage using a dc voltage source (3). An array of resistors (4) or capacitors can be made to discharge to the wire screen anode by means of a low energy high voltage pulse circuit (5) producing sufficient preionization in the region between the anode and cathode to initiate and control the main discharge. The invention has been demonstrated to be useful as a CO.sub.2 laser oscillator and pulse-smoother. It can be reliably operated in the sealed-off mode.

  15. Direct current-self-sustained non-ambipolar plasma at low pressure

    SciTech Connect (OSTI)

    Chen, Zhiying; Chen, Lee; Funk, Merritt

    2013-12-16

    For decades, non-ambipolar diffusion has been observed and studied in laboratory plasmas that contain a double layer. However, self-sustained non-ambipolar plasma has yet to be demonstrated. This article reports the method and results for achieving such a condition at low pressure, with a wide power range (as low as 6 W). The findings reveal that to achieve self-sustained non-ambipolar plasma, both the balance between electron and ion heating and the space-potential gradient are critical. The plasma reactor developed in this work has potential applications that include microelectronic surface processing and space propulsion, via space-charge-neutral plasma-beam thruster, when operated in the high power regime.

  16. Thermodynamic assessment of microencapsulated sodium carbonate slurry for carbon capture

    SciTech Connect (OSTI)

    Stolaroff, Joshuah K.; Bourcier, William L.

    2014-01-01

    Micro-encapsulated Carbon Sorbents (MECS) are a new class of carbon capture materials consisting of a CO?- absorbing liquid solvent contained within solid, CO?-permeable, polymer shells. MECS enhance the rate of CO? absorption for solvents with slow kinetics and prevent solid precipitates from scaling and fouling equipment, two factors that have previously limited the use of sodium carbonate solution for carbon capture. Here, we examine the thermodynamics of sodium carbonate slurries for carbon capture. We model the vapour-liquid-solid equilibria of sodium carbonate and find several features that can contribute to an energy-efficient capture process: very high CO? pressures in stripping conditions, relatively low water vapour pressures in stripping conditions, and good swing capacity. The potential energy savings compared with an MEA system are discussed.

  17. Thermodynamic assessment of microencapsulated sodium carbonate slurry for carbon capture

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

    Stolaroff, Joshuah K.; Bourcier, William L.

    2014-01-01

    Micro-encapsulated Carbon Sorbents (MECS) are a new class of carbon capture materials consisting of a CO₂- absorbing liquid solvent contained within solid, CO₂-permeable, polymer shells. MECS enhance the rate of CO₂ absorption for solvents with slow kinetics and prevent solid precipitates from scaling and fouling equipment, two factors that have previously limited the use of sodium carbonate solution for carbon capture. Here, we examine the thermodynamics of sodium carbonate slurries for carbon capture. We model the vapour-liquid-solid equilibria of sodium carbonate and find several features that can contribute to an energy-efficient capture process: very high CO₂ pressures in stripping conditions,more » relatively low water vapour pressures in stripping conditions, and good swing capacity. The potential energy savings compared with an MEA system are discussed.« less

  18. Microwave ECR plasma electron flood for low pressure wafer charge neutralization

    SciTech Connect (OSTI)

    Vanderberg, Bo; Nakatsugawa, Tomoya; Divergilio, William

    2012-11-06

    Modern ion implanters typically use dc arc discharge Plasma Electron Floods (PEFs) to neutralize wafer charge. The arc discharge requires using at least some refractory metal hardware, e.g. a thermionically emitting filament, which can be undesirable in applications where no metallic contamination is critical. rf discharge PEFs have been proposed to mitigate contamination risks but the gas flows required can result in high process chamber pressures. Axcelis has developed a microwave electron cyclotron resonance (ECR) PEF to provide refractory metals contamination-free wafer neutralization with low gas flow requirement. Our PEF uses a custom, reentrant cusp magnet field providing ECR and superior electron confinement. Stable PEF operation with extraction slits sized for 300 mm wafers can be attained at Xe gas flows lower than 0.2 sccm. Electron extraction currents can be as high as 20 mA at absorbed microwave powers < 70 W. On Axcelis' new medium current implanter, plasma generation has proven robust against pressure transients caused by, for example, photoresist outgassing by high power ion beams. Charge monitor and floating potential measurements along the wafer surface corroborate adequate wafer charge neutralization for low energy, high current ion beams.

  19. Evaluation of plasma melter technology for verification of high-sodium content low-level radioactive liquid wastes: Demonstration test No. 4 preliminary test report

    SciTech Connect (OSTI)

    McLaughlin, D.F.; Gass, W.R.; Dighe, S.V.; D`Amico, N.; Swensrud, R.L.; Darr, M.F.

    1995-01-10

    This document provides a preliminary report of plasma arc vitrification testing by a vendor in support of the Hanford Tank Waste Remediation System Low-Level Waste (LLW) Vitrification Program. Phase I test conduct included 26 hours (24 hours steady state) of melting of simulated high-sodium low-level radioactive liquid waste. Average processing rate was 4.9 kg/min (peak rate 6.2 kg/min), producing 7330 kg glass product. Free-flowing glass pour point was 1250 C, and power input averaged 1530 kW(e), for a total energy consumption of 19,800 kJ/kg glass. Restart capability was demonstrated following a 40-min outage involving the scrubber liquor heat exchanger, and glass production was continued for another 2 hours. Some volatility losses were apparent, probably in the form of sodium borates. Roughly 275 samples were collected and forwarded for analysis. Sufficient process data were collected for heat/material balances. Recommendations for future work include lower boron contents and improved tuyere design/operation.

  20. Development of the High-Pressure Direct-Injected, Ultra Low-NOx Natural Gas Engine: Final Report

    SciTech Connect (OSTI)

    Duggal, V. K.; Lyford-Pike, E. J.; Wright, J. F.; Dunn, M.; Goudie, D.; Munshi, S.

    2004-05-01

    Subcontractor report details work done by Cummins and Westport Innovations to develop a heavy-duty, low-NOx, high-pressure direct-injection natural gas engine for the Next Generation Natural Gas Vehicle activity.

  1. Structural integrity assessment of carbon and low-alloy steel pressure vessels using a simplified fracture mechanics procedure

    SciTech Connect (OSTI)

    Rana, M.D. . Research and Development Dept.)

    1994-08-01

    This paper describes a simplified fracture analysis procedure which was developed by Pellini to quantify fracture critical-crack sizes and crack-arrest temperatures of carbon and low-alloy steel pressure vessels. Fracture analysis diagrams have been developed using the simplified analysis procedure for various grades of carbon and low-alloy steels used in the construction of ASME, Section VIII, Division 1 pressure vessels. Structural integrity assessments have been conducted from the analysis diagrams.

  2. Oxidation behavior of V-Cr-Ti alloys in low-partial-pressure oxygen environments

    SciTech Connect (OSTI)

    Natesan, K.; Uz, M.

    1998-09-01

    A test program is in progress at Argonne National Laboratory to evaluate the effect of pO{sub 2} in the exposure environment on oxygen uptake, scaling kinetics, and scale microstructure in V-Cr-Ti alloys. The data indicate that the oxidation process follows parabolic kinetics in all of the environments used in the present study. From the weight change data, parabolic rate constants were evaluated as a function of temperature and exposure environment. The temperature dependence of the parabolic rate constants was described by an Arrhenius relationship. Activation energy for the oxidation process was fairly constant in the oxygen pressure range of 1 {times} 10{sup {minus}6} to 1 {times} 10{sup {minus}1} torr for both the alloys. The activation energy for oxidation in air was significantly lower than in low-pO{sub 2} environments, and for oxidation in pure O{sub 2} at 760 torr was much lower than in low-pO{sub 2} environments. X-ray diffraction analysis of the specimens showed that VO{sub 2} was the dominant phase in low-pO{sub 2} environments, while V{sub 2}O{sub 5} was dominant in air and in pure oxygen at 76f0 torr.

  3. Low pressure shock initiation of porous HMX for two grain size distributions and two densities

    SciTech Connect (OSTI)

    Gustavsen, R.L.; Sheffield, S.A.; Alcon, R.R.

    1995-09-01

    Shock initiation measurements have been made on granular HMX (octotetramethylene tetranitrainine) for two particle size distributions and two densities. Samples were pressed to either 65% or 73% of crystal density from fine ({approx} 10 {mu}m grain size) and coarse (broad distribution of grain sizes peaking at {approx} 150 {mu}m) powders. Planar shocks of 0.2--1 GPa were generated by impacting gas gun driven projectiles on plastic targets containing the HMX. Wave profiles were measured at the input and output of the {approx} 3.9 mm thick HMX layer using electromagnetic particle velocity gauges. The initiation behavior for the two particle size distributions was very different. The coarse HMX began initiating at input pressures as low as 0.5 GPa. Transmitted wave profiles showed relatively slow reaction with most of the buildup occurring at the shock front. In contrast, the fine particle HMX did not begin to initiate at pressures below 0.9 GPa. When the fine powder did react, however, it did so much faster than the coarse HMX. These observations are consistent with commonly held ideas about bum rates being correlated to surface area, and initiation thresholds being correlated with the size and temperature of the hot spots created by shock passage. For each size, the higher density pressings were less sensitive than the lower density pressings.

  4. Thermodynamics of methane adsorption on copper HKUST-1 at low pressure

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

    Wu, Di; Guo, Xiaofeng; Sun, Hui; Navrotsky, Alexandra

    2015-06-11

    Metal–organic frameworks (MOFs) can be engineered as natural gas storage materials by tuning the pore structures and surface properties. Here we report the direct measurement of CH₄ adsorption enthalpy on a paddlewheel MOF (Cu HKUST-1) using gas adsorption calorimetry at 25 °C at low pressures (below 1 bar). In this pressure region, the CH₄–CH₄ intermolecular interactions are minimized and the energetics solely reflects the CH₄–MOF interactions. Our results suggest moderately exothermic physisorption with an enthalpy of -21.1 ± 1.1 kJ/mol CH₄ independent of coverage. The calorimetric investigation complements previous computational and crystallographic studies by providing zero coverage enthalpies of CH₄more » adsorption. The analysis of the new and literature data suggests that in initial stages of adsorption the CH₄–HKUST-1 interaction tends to be more sensitive to the pore dimension than to the guest polarizability, suggesting a less specific chemical binding role for the open Cu site.« less

  5. Low tritium partial pressure permeation system for mass transport measurement in lead lithium eutectic

    SciTech Connect (OSTI)

    Pawelko, R. J.; Shimada, M.; Katayama, K.; Fukada, S.; Humrickhouse, P. W.; Terai, T.

    2015-11-28

    This paper describes a new experimental system designed to investigate tritium mass transfer properties in materials important to fusion technology. Experimental activities were carried out at the Safety and Tritium Applied Research (STAR) facility located at the Idaho National Laboratory (INL). The tritium permeation measurement system was developed as part of the Japan/US TITAN collaboration to investigate tritium mass transfer properties in liquid lead lithium eutectic (LLE) alloy. The experimental system is configured to measure tritium mass transfer properties at low tritium partial pressures. Initial tritium permeation scoping tests were conducted on a 1 mm thick α-Fe plate to determine operating parameters and to validate the experimental technique. A second series of permeation tests was then conducted with the α-Fe plate covered with an approximately 8.5 mm layer of liquid lead lithium eutectic alloy (α-Fe/LLE). We present preliminary tritium permeation data for α-Fe and α-Fe/LLE at temperatures between 400 and 600°C and at tritium partial pressures between 1.7E-3 and 2.5 Pa in helium. Preliminary results for the α-Fe plate and α-Fe/LLE indicate that the data spans a transition region between the diffusion-limited regime and the surface-limited regime. In conclusion, additional data is required to determine the existence and range of a surface-limited regime.

  6. Low tritium partial pressure permeation system for mass transport measurement in lead lithium eutectic

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

    Pawelko, R. J.; Shimada, M.; Katayama, K.; Fukada, S.; Humrickhouse, P. W.; Terai, T.

    2015-11-28

    This paper describes a new experimental system designed to investigate tritium mass transfer properties in materials important to fusion technology. Experimental activities were carried out at the Safety and Tritium Applied Research (STAR) facility located at the Idaho National Laboratory (INL). The tritium permeation measurement system was developed as part of the Japan/US TITAN collaboration to investigate tritium mass transfer properties in liquid lead lithium eutectic (LLE) alloy. The experimental system is configured to measure tritium mass transfer properties at low tritium partial pressures. Initial tritium permeation scoping tests were conducted on a 1 mm thick α-Fe plate to determinemore » operating parameters and to validate the experimental technique. A second series of permeation tests was then conducted with the α-Fe plate covered with an approximately 8.5 mm layer of liquid lead lithium eutectic alloy (α-Fe/LLE). We present preliminary tritium permeation data for α-Fe and α-Fe/LLE at temperatures between 400 and 600°C and at tritium partial pressures between 1.7E-3 and 2.5 Pa in helium. Preliminary results for the α-Fe plate and α-Fe/LLE indicate that the data spans a transition region between the diffusion-limited regime and the surface-limited regime. In conclusion, additional data is required to determine the existence and range of a surface-limited regime.« less

  7. Thermodynamics of methane adsorption on copper HKUST-1 at low pressure

    SciTech Connect (OSTI)

    Wu, Di; Guo, Xiaofeng; Sun, Hui; Navrotsky, Alexandra

    2015-06-11

    Metal–organic frameworks (MOFs) can be engineered as natural gas storage materials by tuning the pore structures and surface properties. Here we report the direct measurement of CH₄ adsorption enthalpy on a paddlewheel MOF (Cu HKUST-1) using gas adsorption calorimetry at 25 °C at low pressures (below 1 bar). In this pressure region, the CH₄–CH₄ intermolecular interactions are minimized and the energetics solely reflects the CH₄–MOF interactions. Our results suggest moderately exothermic physisorption with an enthalpy of -21.1 ± 1.1 kJ/mol CH₄ independent of coverage. The calorimetric investigation complements previous computational and crystallographic studies by providing zero coverage enthalpies of CH₄ adsorption. The analysis of the new and literature data suggests that in initial stages of adsorption the CH₄–HKUST-1 interaction tends to be more sensitive to the pore dimension than to the guest polarizability, suggesting a less specific chemical binding role for the open Cu site.

  8. Experimental investigations of driving frequency effect in low-pressure capacitively coupled oxygen discharges

    SciTech Connect (OSTI)

    Liu, Jia; Liu, Yong-Xin; Liu, Gang-Hu; Gao, Fei; Wang, You-Nian

    2015-04-14

    The effect of driving frequency on the electron density is investigated in low-pressure capacitively coupled oxygen plasmas by utilizing a floating hairpin probe. The power absorbed by the plasma is investigated and it is found that the power lost in the matching network can reach 50% or higher under certain conditions. The effect of driving frequency on the electron density is studied from two aspects, i.e., constant absorbed power and electrode voltage. In the former case, the electron density increases with the driving frequency increasing from 13.56 to 40.68 MHz and slightly changes depending on the gas pressures with the frequency further increasing to 100 MHz. In the latter case, the electron density rapidly increases when the driving frequency increases from 13.56 to 40.68 MHz, and then decreases with the frequency further increasing to 100 MHz. The electron series resonance is observed at 40.68 MHz and can be attributed to the higher electron density. And the standing wave effect also plays an important role in increasing electron density at 100 MHz and 2.6 Pa.

  9. Simulation study of nanoparticle coating in a low pressure plasma reactor

    SciTech Connect (OSTI)

    Pourali, N.; Foroutan, G.

    2015-02-15

    A self-consistent combination of plasma fluid model, nanoparticle heating model, and surface deposition model is used to investigate the coating of nanosize particles by amorphous carbon layers in a low pressure plasma reactor. The numerical results show that, owing to the net heat release in the surface reactions, the particle temperature increases and its equilibrium value remains always 50?K above the background gas temperature. The deposition rate decreases with increasing of the particle temperature and the corresponding time scale is of the order of 10?ms. The deposition rate is also strongly affected by the change in plasma parameters. When the electron temperature is increased, the deposition rate first increases due to the enhanced ion and radical generation, shows a maximum and then declines as the particle temperature rises above the gas temperature. An enhancement in the background gas pressure and/or temperature leads to a reduction in the deposition rate, which can be explained in terms of the enhanced etching by atomic hydrogen and particle heating by the background gas.

  10. Experimental observation of standing wave effect in low-pressure very-high-frequency capacitive discharges

    SciTech Connect (OSTI)

    Liu, Yong-Xin; Gao, Fei; Liu, Jia; Wang, You-Nian

    2014-07-28

    Radial uniformity measurements of plasma density were carried out by using a floating double probe in a cylindrical (21 cm in electrode diameter) capacitive discharge reactor driven over a wide range of frequencies (27–220 MHz). At low rf power, a multiple-node structure of standing wave effect was observed at 130 MHz. The secondary density peak caused by the standing wave effect became pronounced and shifts toward the axis as the driving frequency further to increase, indicative of a much more shortened standing-wave wavelength. With increasing rf power, the secondary density peak shift toward the radial edge, namely, the standing-wave wavelength was increased, in good qualitative agreement with the previous theory and simulation results. At higher pressures and high frequencies, the rf power was primarily deposited at the periphery of the electrode, due to the fact that the waves were strongly damped as they propagated from the discharge edge into the center.

  11. Performance uprate of a geothermal steam turbine case study: Brady Power low pressure turbine

    SciTech Connect (OSTI)

    Miller, R.J. Jr.

    1997-12-31

    The output of a low pressure steam turbine operating in a geothermal power plant has been increased 10.9% by performing an efficiency uprate. The performance of the turbine was studied, resulting in a design for re-optimizing the steam path. New high-efficiency components were blended with existing turbine parts to achieve large output gains at minimum cost. Because the uprate was performed by a non-OEM, the analysis and manufacturing techniques were specifically tailored for the aftermarket. The work was completed on the spare turbine components, thereby allowing the plant to continue operation while the uprated parts were being manufactured. The predicted output gains were confirmed by field performance tests of the existing and uprated turbines.

  12. A handheld low temperature atmospheric pressure air plasma gun for nanomaterial synthesis in liquid phase

    SciTech Connect (OSTI)

    Yu, Shuang; Wang, Kaile; Zuo, Shasha; Liu, Jiahui; Zhang, Jue Fang, Jing

    2015-10-15

    A handheld low temperature atmospheric pressure air plasma gun based on a dielectric barrier structure with hollow electrodes was proposed. The portable plasma gun with an embedded mini air pump was driven by a 12 V direct voltage battery. The air plasma jet generated from the gun could be touched without a common shock hazard. Besides working in air, the plasma gun can also work in water. The diagnostic result of optical emission spectroscopy showed the difference in reactive species of air plasma jet between in air and in water. The plasma gun was excited in 20 ml chloroauric acid aqueous solution with a concentration of 1.214 mM. A significant amount of gold nanoparticles were synthesized after 2 min continuous discharge. The plasma gun with these unique features is applicable in plasma medicine, etching, and s-nthesis of nanomaterials.

  13. Electrical breakdown at low pressure in the presence of a weak magnetic field

    SciTech Connect (OSTI)

    Alport, M.J.; Antoniades, J.A.; Boyd, D.A.; Greaves, R.G.; Ellis, R.F. )

    1990-05-01

    Electron trapping in crossed electric and magnetic fields is an important mechanism by which electrical discharges can develop in low pressure gases. The authors report observations of discharges produced by this mechanism around a spherical anode in two space simulation chambers, namely the Space Plasma Interaction Experiment (SPIE) at the University of Maryland, and the NASA-Lewis B-2 chamber. They have identified two types of discharges in these experiments. In the B-2 chamber, the breakdown takes the form of a runaway dischage with spherical topology, limited only by the ability of the power supply to provide the current. In the SPIE chamber this type of discharge also occurs, in addition to a low current toroidal discharge which is observed at higher magnetic fields. They present measurements of both types of discharge and show how the trapping effect of the magnetic field together with secondary electron emission by high energy ion bombardment of the chamber walls may initiate and sustains these discharges.

  14. Neutron diffraction and electrical transport studies on magnetic ordering in terbium at high pressures and low temperatures

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

    Thomas, Sarah A.; Montgomery, Jeffrey M.; Tsoi, Georgiy M.; Vohra, Yogesh K.; Chesnut, Gary N.; Weir, Samuel T.; Tulk, Christopher A.; dos Santos, Antonio M.

    2013-06-11

    Neutron diffraction and electrical transport measurements have been carried out on the heavy rare earth metal terbium at high pressures and low temperatures in order to elucidate the onset of ferromagnetic order as a function of pressure. The electrical resistance measurements show a change in slope as the temperature is lowered through the ferromagnetic Curie temperature. The temperature of this ferromagnetic transition decreases from approximately 240 K at ambient pressure at a rate of –16.7 K/GPa up to a pressure of 3.6 GPa, at which point the onset of ferromagnetic order is suppressed. Neutron diffraction measurements as a function ofmore » pressure at temperatures ranging from 90 K to 290 K confirm that the change of slope in the resistance is associated with the ferromagnetic ordering, since this occurs at pressures similar to those determined from the resistance results at these temperatures. Furthermore, a change in ferromagnetic ordering as the pressure is increased above 3.6 GPa is correlated with the phase transition from the ambient hexagonal close packed (hcp) structure to an α-Sm type structure at high pressures.« less

  15. Neutron diffraction and electrical transport studies on magnetic ordering in terbium at high pressures and low temperatures

    SciTech Connect (OSTI)

    Thomas, Sarah A.; Montgomery, Jeffrey M.; Tsoi, Georgiy M.; Vohra, Yogesh K.; Chesnut, Gary N.; Weir, Samuel T.; Tulk, Christopher A.; dos Santos, Antonio M.

    2013-06-11

    Neutron diffraction and electrical transport measurements have been carried out on the heavy rare earth metal terbium at high pressures and low temperatures in order to elucidate the onset of ferromagnetic order as a function of pressure. The electrical resistance measurements show a change in slope as the temperature is lowered through the ferromagnetic Curie temperature. The temperature of this ferromagnetic transition decreases from approximately 240 K at ambient pressure at a rate of –16.7 K/GPa up to a pressure of 3.6 GPa, at which point the onset of ferromagnetic order is suppressed. Neutron diffraction measurements as a function of pressure at temperatures ranging from 90 K to 290 K confirm that the change of slope in the resistance is associated with the ferromagnetic ordering, since this occurs at pressures similar to those determined from the resistance results at these temperatures. Furthermore, a change in ferromagnetic ordering as the pressure is increased above 3.6 GPa is correlated with the phase transition from the ambient hexagonal close packed (hcp) structure to an α-Sm type structure at high pressures.

  16. Advanced Models of LWR Pressure Vessel Embrittlement for Low Flux-HighFluence Conditions

    SciTech Connect (OSTI)

    Odette, G. Robert; Yamamoto, Takuya

    2013-06-17

    Neutron embrittlement of reactor pressure vessels (RPVs) is an unresolved issue for light water reactor life extension, especially since transition temperature shifts (TTS) must be predicted for high 80-year fluence levels up to approximately 1,020 n/cm{sup 2}, far beyond the current surveillance database. Unfortunately, TTS may accelerate at high fluence, and may be further amplified by the formation of late blooming phases that result in severe embrittlement even in low-copper (Cu) steels. Embrittlement by this mechanism is a potentially significant degradation phenomenon that is not predicted by current regulatory models. This project will focus on accurately predicting transition temperature shifts at high fluence using advanced physically based, empirically validated and calibrated models. A major challenge is to develop models that can adjust test reactor data to account for flux effects. Since transition temperature shifts depend on synergistic combinations of many variables, flux-effects cannot be treated in isolation. The best current models systematically and significantly under-predict transition temperature at high fluence, although predominantly for irradiations at much higher flux than actual RPV service. This project will integrate surveillance, test reactor and mechanism data with advanced models to address a number of outstanding RPV embrittlement issues. The effort will include developing new databases and preliminary models of flux effects for irradiation conditions ranging from very low (e.g., boiling water reactor) to high (e.g., accelerated test reactor). The team will also develop a database and physical models to help predict the conditions for the formation of Mn-Ni-Si late blooming phases and to guide future efforts to fully resolve this issue. Researchers will carry out other tasks on a best-effort basis, including prediction of transition temperature shift attenuation through the vessel wall, remediation of embrittlement by annealing

  17. An experimental study on sub-cooled flow boiling CHF of R134a at low pressure condition with atmospheric pressure (AP) plasma assisted surface modification

    SciTech Connect (OSTI)

    Kim, Seung Jun; Zou, Ling; Jones, Barclay G.

    2015-02-01

    In this study, sub-cooled flow boiling critical heat flux tests at low pressure were conducted in a rectangular flow channel with one uniformly heated surface, using simulant fluid R-134a as coolant. The experiments were conducted under the following conditions: (1) inlet pressure (P) of 400-800 kPa, (2) mass flux (G) of 124-248 kg/m2s, (3) inlet sub-cooling enthalpy (ΔHi) of 12~ 26 kJ/kg. Parametric trends of macroscopic system parameters (G, P, Hi) were examined by changing inlet conditions. Those trends were found to be generally consistent with previous understandings of CHF behavior at low pressure condition (i.e. reduced pressure less than 0.2). A fluid-to-fluid scaling model was utilized to convert the test data obtained with the simulant fluid (R-134a) into the prototypical fluid (water). The comparison between the converted CHF of equivalent water and CHF look-up table with same operation conditions were conducted, which showed good agreement. Furthermore, the effect of surface wettability on CHF was also investigated by applying atmospheric pressure plasma (AP-Plasma) treatment to modify the surface characteristic. With AP-Plasma treatment, the change of microscopic surface characteristic was measured in terms of static contact angle. The static contact angle was reduced from 80° on original non-treated surface to 15° on treated surface. An enhancement of 18% on CHF values under flow boiling conditions were observed on AP-Plasma treated surfaces compared to those on non-treated heating surfaces.

  18. Transport of low pressure electronegative SF{sub 6} plasma through a localized magnetic filter

    SciTech Connect (OSTI)

    Levko, D.; Garrigues, L.; Hagelaar, G. J. M.

    2014-08-15

    The generation of an ion-ion plasma where only few electrons are present in the discharge could be appropriated in the context of ion plasma source applications. We present in this paper results obtained with a one-dimensional fluid model in the context of low pressure electronegative SF{sub 6} plasma. Without magnetic field, results show that the electron density is still large in the discharge. With a localized magnetic filter, where the magnetic field strength is such that the transport of the electrons is affected while the transport of ion species remains unmagnetized, we show that a region with a negativepositive ion plasma is found downstream the magnetic filter. The negative ions are produced in the filter due to the decrease of electron temperature. We also find conditions when the plasma sheath near the biased electrode collapses and the negative ion extraction from the plasma becomes possible. In addition, the influence of E??B electron transport on the one-dimensional model results is discussed.

  19. Evaluation of HFC-245ca for commercial use in low pressure chillers. Final report, Volume I

    SciTech Connect (OSTI)

    Keuper, E.F.

    1996-03-01

    Federal regulations banned the production of CFC-11 on January 1, 1996. HCFC-123, the only commercial alternative, will be limited to service applications after January 1, 2020 and will be eliminated from production on January 1, 2030. HFC-245ca has been identified as a potential replacement for CFC-11 in retrofit applications and for HCFC-123 in new chillers, but the marginal flammability of HFC-245ca is a major obstacle to its commercial use as a refrigerant in the United States. This report assesses the commercial viability of HFC-245ca based on its experimental performance in a direct drive low pressure centrifugal chiller exclusive of its flammability characteristics. Three different impeller diameters were tested in the chiller, with all impellers having identical discharge blade angles. Experimental work included tests in a 200 ton 3 stage direct drive chiller with 3 impeller sets properly sized for each of three refrigerants, CFC-11, HCFC-123, and HFC-245ca. The commercial viability assessment focused on both retrofit and new product performance and cost.

  20. Dynamic effect of sodium-water reaction in fast flux test facility power addition sodium pipes

    SciTech Connect (OSTI)

    Huang, S.N.; Anderson, M.J.

    1990-03-01

    The Fast Flux Facility (FFTF) is a demonstration and test facility of the sodium-cooled fast breeder reactor. A power addition'' to the facility is being considered to convert some of the dumped, unused heat into electricity generation. Components and piping systems to be added are sodium-water steam generators, sodium loop extensions from existing dump heat exchangers to sodium-water steam generators, and conventional water/steam loops. The sodium loops can be subjected to the dynamic loadings of pressure pulses that are caused by postulated sodium leaks and subsequent sodium-water reaction in the steam generator. The existing FFTF secondary pipes and the new power addition sodium loops were evaluated for exposure to the dynamic effect of the sodium-water reaction. Elastic and simplified inelastic dynamic analyses were used in this feasibility study. The results indicate that both the maximum strain and strain range are within the allowable limits. Several cycles of the sodium-water reaction can be sustained by the sodium pipes that are supported by ordinary pipe supports and seismic restraints. Expensive axial pipe restraints to withstand the sodium-water reaction loads are not needed, because the pressure-pulse-induced alternating bending stresses act as secondary stresses and the pressure pulse dynamic effect is a deformation-controlled quantity and is self-limiting. 14 refs., 7 figs., 3 tabs.

  1. Structural and magnetic phase transitions in gadolinium under high pressures and low temperatures

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

    Samudrala, Gopi K.; Tsoi, Georgiy M.; Weir, Samuel T.; Vohra, Yogesh K.

    2014-11-07

    High pressure structural transition studies have been carried out on rare earth metal gadolinium in a diamond anvil cell at room temperature to 169 GPa. Gadolinium has been compressed to 38% of its initial volume at this pressure. With increasing pressure, a crystal structure sequence of hcp → Smtype→ dhcp → fcc → dfcc → monoclinic has been observed in our studies on gadolinium. The measured equation of state of gadolinium is presented to 169 GPa at ambient temperature. Magnetic ordering temperature of gadolinium has been studied using designer diamond anvils to a pressure of 25 GP and a temperaturemore » of 10 K. The magnetic ordering temperature has been determined from the four-point electrical resistivity measurements carried out on gadolinium. Furthermore, our experiments show that the magnetic transition temperature decreases with increasing pressure to 19 GPa and then increases when gadolinium is subjected to higher pressures.« less

  2. Structural and magnetic phase transitions in gadolinium under high pressures and low temperatures

    SciTech Connect (OSTI)

    Samudrala, Gopi K.; Tsoi, Georgiy M.; Weir, Samuel T.; Vohra, Yogesh K.

    2014-11-07

    High pressure structural transition studies have been carried out on rare earth metal gadolinium in a diamond anvil cell at room temperature to 169 GPa. Gadolinium has been compressed to 38% of its initial volume at this pressure. With increasing pressure, a crystal structure sequence of hcp → Smtype→ dhcp → fcc → dfcc → monoclinic has been observed in our studies on gadolinium. The measured equation of state of gadolinium is presented to 169 GPa at ambient temperature. Magnetic ordering temperature of gadolinium has been studied using designer diamond anvils to a pressure of 25 GP and a temperature of 10 K. The magnetic ordering temperature has been determined from the four-point electrical resistivity measurements carried out on gadolinium. Furthermore, our experiments show that the magnetic transition temperature decreases with increasing pressure to 19 GPa and then increases when gadolinium is subjected to higher pressures.

  3. High pressure low temperature studies on 1-2-2 iron-based superconductors using designer diamond cells

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

    Uhoya, Walter O.; Tsoi, Georgiy M.; Vohra, Yogesh K.; Mitchell, Jonathan, E.; Safa-Sefat, Athena; Weir, Samuel

    2013-01-01

    In this study, high pressure low temperature electrical resistance measurements were carried out on a series of 122 iron-based superconductors using a designer diamond anvil cell. These studies were complemented by image plate x-ray diffraction measurements under high pressures and low temperatures at beamline 16-BM-D, HPCAT, Advanced Photon Source. A common feature of the 1-2-2 iron-based materials is the observation of anomalous compressibility effects under pressure and a Tetragonal (T) to Collapsed Tetragonal (CT) phase transition under high pressures. Specific studies on antiferromagnetic spin-density-wave Ba0.5Sr0.5Fe2As2 and Ba(Fe0.9Ru0.1)2As2 samples are presented to 10 K and 41 GPa. The collapsed tetragonal phasemore » was observed at a pressure of 14 GPa in Ba0.5Sr0.5Fe2As2 at ambient temperature. The highest superconducting transition temperature in Ba0.5Sr0.5Fe2As2 was observed to be at 32 K at a pressure of 4.7 GPa. The superconductivity was observed to be suppressed on transformation to the CT phase in 122 materials.« less

  4. Evaluation of melter system technologies for vitrification of high-sodium content low-level radioactive liquid wastes

    SciTech Connect (OSTI)

    Wilson, C.N.

    1994-03-21

    Westinghouse Hanford Company (WHC) is conducting a two-phased demonstration testing and evaluation of candidate melter system technologies for vitrification of Hanford Site low-level tank wastes. The testing is to be performed by melter equipment and vitrification technology commercial suppliers. This Statement of Work is for Phases 1 and 2 of the demonstration testing program. The primary objective of the demonstration testing is to identify the best available melter system technology for the Hanford Site LLW vitrification facility. Data obtained also will support various WHC engineering studies and conceptual design of the LLW vitrification facility. Multiple technologies will be selected for demonstration and evaluation. Testing will be conducted using non-radioactive LLW simulants in Seller-specified pilot/testing facilities.

  5. High- and low-temperature-stable thermite composition for producing high-pressure, high-velocity gases

    DOE Patents [OSTI]

    Halcomb, Danny L.; Mohler, Jonathan H.

    1990-10-16

    A high- and low-temperature-stable thermite composition for producing high-pressure and high-velocity gases comprises an oxidizable metal, an oxidizing reagent, and a high-temperature-stable gas-producing additive selected from the group consisting of metal carbides and metal nitrides.

  6. CALANDRIA TYPE SODIUM GRAPHITE REACTOR

    DOE Patents [OSTI]

    Peterson, R.M.; Mahlmeister, J.E.; Vaughn, N.E.; Sanders, W.J.; Williams, A.C.

    1964-02-11

    A sodium graphite power reactor in which the unclad graphite moderator and fuel elements are contained within a core tank is described. The core tank is submersed in sodium within the reactor vessel. Extending longitudinally through the core thnk are process tubes with fuel elements positioned therein. A bellows sealing means allows axial expansion and construction of the tubes. Within the core tank, a leakage plenum is located below the graphite, and above the graphite is a gas space. A vent line regulates the gas pressure in the space, and another line removes sodium from the plenum. The sodium coolant flows from the lower reactor vessel through the annular space between the fuel elements and process tubes and out into the reactor vessel space above the core tank. From there, the heated coolant is drawn off through an outlet line and sent to the heat exchange. (AEC)

  7. Graphene chemical vapor deposition at very low pressure: The impact of substrate surface self-diffusion in domain shape

    SciTech Connect (OSTI)

    Cunha, T. H. R.; Ek-Weis, J.; Lacerda, R. G.; Ferlauto, A. S., E-mail: ferlauto@fisica.ufmg.br [Department of Physics, Federal University of Minas Gerais, Belo Horizonte 31270-901 (Brazil)

    2014-08-18

    The initial stages of graphene chemical vapor deposition at very low pressures (<10{sup ?5?}Torr) were investigated. The growth of large graphene domains (?up to 100??m) at very high rates (up to 3??m{sup 2} s{sup ?1}) has been achieved in a cold-wall reactor using a liquid carbon precursor. For high temperature growth (>900?C), graphene grain shape and symmetry were found to depend on the underlying symmetry of the Cu crystal, whereas for lower temperatures (<900?C), mostly rounded grains are observed. The temperature dependence of graphene nucleation density was determined, displaying two thermally activated regimes, with activation energy values of 6??1?eV for temperatures ranging from 900?C to 960?C and 9??1?eV for temperatures above 960?C. The comparison of such dependence with the temperature dependence of Cu surface self-diffusion suggests that graphene growth at high temperatures and low pressures is strongly influenced by copper surface rearrangement. We propose a model that incorporates Cu surface self-diffusion as an essential process to explain the orientation correlation between graphene and Cu crystals, and which can clarify the difference generally observed between graphene domain shapes in atmospheric-pressure and low-pressure chemical vapor deposition.

  8. Negative-ion yield in low-pressure radio frequency discharges in hydrogen: Particle modeling and vibrational kinetics

    SciTech Connect (OSTI)

    Diomede, P.; Longo, S.; Capitelli, M.

    2006-03-15

    A theoretical study of the complex interplay between the vibrational kinetics and the plasma dynamics in low-pressure hydrogen plasmas produced by radio frequency discharges is performed. The study is realized by means of a one-dimensional particle model with five species (e, H{sup +}, H{sub 2}{sup +}, H{sub 3}{sup +}, and H{sup -}) while the vibrational/dissociation kinetics is based on a continuum model and the two are self-consistently coupled. In particular, we analyze the influence of pressure.

  9. Irradiation effects in low-alloy reactor pressure vessel steels (Heavy-Section Steel Technology Program Series 4 and 5)

    SciTech Connect (OSTI)

    Berggren, R.G.; McGowan, J.J.; Menke, B.H.; Nanstad, R.K.; Thoms, K.R.

    1984-01-01

    Multiple testing is done at two laboratories of typical nuclear pressure vessel materials (both irradiated and unirradiated) and statistical analyses of the test results. Multiple tests are conducted at each of several test temperatures for each material, standard deviations are determined, and results from the two laboratories are compared. The Fourth Heavy-Section Steel Technology (HSST) Irradiation Series, almost completed, was aimed at elastic-plastic and fully plastic fracture toughness of low-copper weldments (current practice welds). A typical nuclear pressure vessel plate steel was included for statistical purposes. The Fifth HSST Irradiation Series, now in progress, is aimed at determining the shape of the K/sub IR/ curve after significant radiation-induced shift of the transition temperatures. This series includes irradiated test specimens of thicknesses up to 100 mm and weldment compositions typical of early nuclear power reactor pressure vessel welds.

  10. A compact high-performance low-field NMR apparatus for measurements on fluids at very high pressures and temperatures

    SciTech Connect (OSTI)

    Freedman, R.; Anand, V. Ganesan, K.; Tabrizi, P.; Torres, R.; Grant, B.; Catina, D.; Ryan, D.; Borman, C.; Krueckl, C.

    2014-02-15

    We discuss an innovative new high-performance apparatus for performing low-field Nuclear Magnetic Resonance (NMR) relaxation times and diffusion measurements on fluids at very high pressures and high temperatures. The apparatus sensor design and electronics specifications allow for dual deployment either in a fluid sampling well logging tool or in a laboratory. The sensor and electronics were designed to function in both environments. This paper discusses the use of the apparatus in a laboratory environment. The operating temperature and pressure limits, and the signal-to-noise ratio (SNR) of the new system exceed by a very wide margin what is currently possible. This major breakthrough was made possible by a revolutionary new sensor design that breaks many of the rules of conventional high pressure NMR sensor design. A metallic sample holder capable of operating at high pressures and temperatures is provided to contain the fluid under study. The sample holder has been successfully tested for operation up to 36 Kpsi. A solenoid coil wound on a slotted titanium frame sits inside the metallic sample holder and serves as an antenna to transmit RF pulses and receive NMR signals. The metal sample holder is sandwiched between a pair of gradient coils which provide a linear field gradient for pulsed field gradient diffusion measurements. The assembly sits in the bore of a low-gradient permanent magnet. The system can operate over a wide frequency range without the need for tuning the antenna to the Larmor frequency. The SNR measured on a water sample at room temperature is more than 15 times greater than that of the commercial low-field system in our laboratory. Thus, the new system provides for data acquisition more than 200 times faster than was previously possible. Laboratory NMR measurements of relaxations times and diffusion coefficients performed at pressures up to 25 Kpsi and at temperatures up to 175?C with crude oils enlivened with dissolved hydrocarbon gases

  11. Systems for low frequency seismic and infrasound detection of geo-pressure transition zones

    DOE Patents [OSTI]

    Shook, G. Michael; LeRoy, Samuel D.; Benzing, William M.

    2007-10-16

    Methods for determining the existence and characteristics of a gradational pressurized zone within a subterranean formation are disclosed. One embodiment involves employing an attenuation relationship between a seismic response signal and increasing wavelet wavelength, which relationship may be used to detect a gradational pressurized zone and/or determine characteristics thereof. In another embodiment, a method for analyzing data contained within a response signal for signal characteristics that may change in relation to the distance between an input signal source and the gradational pressurized zone is disclosed. In a further embodiment, the relationship between response signal wavelet frequency and comparative amplitude may be used to estimate an optimal wavelet wavelength or range of wavelengths used for data processing or input signal selection. Systems for seismic exploration and data analysis for practicing the above-mentioned method embodiments are also disclosed.

  12. Methods and systems for low frequency seismic and infrasound detection of geo-pressure transition zones

    DOE Patents [OSTI]

    Shook, G. Michael; LeRoy, Samuel D.; Benzing, William M.

    2006-07-18

    Methods for determining the existence and characteristics of a gradational pressurized zone within a subterranean formation are disclosed. One embodiment involves employing an attenuation relationship between a seismic response signal and increasing wavelet wavelength, which relationship may be used to detect a gradational pressurized zone and/or determine characteristics thereof. In another embodiment, a method for analyzing data contained within a response signal for signal characteristics that may change in relation to the distance between an input signal source and the gradational pressurized zone is disclosed. In a further embodiment, the relationship between response signal wavelet frequency and comparative amplitude may be used to estimate an optimal wavelet wavelength or range of wavelengths used for data processing or input signal selection. Systems for seismic exploration and data analysis for practicing the above-mentioned method embodiments are also disclosed.

  13. Experimental and numerical investigations of electron density in low-pressure dual-frequency capacitively coupled oxygen discharges

    SciTech Connect (OSTI)

    Liu, Jia; Wen, De-Qi; Liu, Yong-Xin; Gao, Fei; Lu, Wen-Qi; Wang, You-Nian [School of Physics and Optoelectronic Technology, Dalian University of Technology, Dalian 116024 (China)] [School of Physics and Optoelectronic Technology, Dalian University of Technology, Dalian 116024 (China)

    2013-11-15

    The electron density is measured in low-pressure dual-frequency (2/60 MHz) capacitively coupled oxygen discharges by utilizing a floating hairpin probe. The dependence of electron density at the discharge center on the high frequency (HF) power, low frequency (LF) power, and gas pressure are investigated in detail. A (1D) particle-in-cell/Monte Carlo method is developed to calculate the time-averaged electron density at the discharge center and the simulation results are compared with the experimental ones, and general agreements are achieved. With increasing HF power, the electron density linearly increases. The electron density exhibits different changes with the LF power at different HF powers. At low HF powers (e.g., 30 W in our experiment), the electron density increases with increasing LF power while the electron density decreases with increasing LF power at relatively high HF powers (e.g., 120 W in our experiment). With increasing gas pressure the electron density first increases rapidly to reach a maximum value and then decreases slowly due to the combined effect of the production process by the ionization and the loss processes including the surface and volume losses.

  14. Experimental investigation on the flow instability behavior of a multi-channel boiling natural circulation loop at low-pressures

    SciTech Connect (OSTI)

    Jain, Vikas; Nayak, A.K.; Vijayan, P.K.; Saha, D.; Sinha, R.K.

    2010-09-15

    Natural circulation as a mode of heat removal is being considered as a prominent passive feature in the innovative nuclear reactor designs, particularly in boiling-water-reactors, due to its simplicity and economy. However, boiling natural circulation system poses many challenges to designer due to occurrence of various kinds of instabilities such as excursive instability, density wave oscillations, flow pattern transition instability, geysering and metastable states in parallel channels. This problem assumes greater significance particularly at low-pressures i.e. during startup, where there is great difference in the properties of two phases. In light of this, a parallel channel loop has been designed and installed that has a geometrical resemblance to the pressure-tube-type boiling-water-reactor, to investigate into the behavior of boiling natural circulation. The loop comprises of four identical parallel channels connected between two common plenums i.e. steam drum and header. The recirculation path is provided by a single downcomer connected between steam drum and header. Experiments have been conducted over a wide range of power and pressures (1-10 bar). Two distinct unstable zones are observed with respect to power i.e. corresponding to low power (Type-I) and high power (Type-II) with a stable zone at intermediate powers. The nature of oscillations in terms of their amplitude and frequency and their evolution for Type-I and Type-II instabilities are studied with respect to the effect of heater power and pressure. This paper discusses the evolution of unstable and stable behavior along with the nature of flow oscillation in the channels and the effect of pressure on it. (author)

  15. Calculation of thermophysical properties of sodium. [LMFBR

    SciTech Connect (OSTI)

    Fink, J.K.; Leibowitz, L.

    1981-01-01

    The thermodynamic properties of sodium previously recommended by Padilla have been updated. As much as possible, the approach described by Padilla has been used. For sodium in the states of saturated liquid and vapor, subcooled liquid and superheated vapor, the following thermodynamic properties were determined: enthalpy, heat capacity (constant pressure and constant volume), pressure, density, thermal-expansion coefficient, and compressibility (adiabatic and isothermal). In addition to the above properties, thermodynamic properties including heat of fusion, heat of vaporization, surface tension, speed of sound and transport properties of themal conductivity, thermal diffusivity, emissivity, and viscosity were determined for saturated sodium.

  16. Low-temperature hydrothermal synthesis of the three-layered sodium cobaltite P3-Na{sub x}CoO{sub 2} (x ∼ 0.60)

    SciTech Connect (OSTI)

    Miclau, M.; Bokinala, K.; Miclau, N.

    2014-06-01

    Highlights: • We report direct synthesis of the high temperature stable phase, P3-Na{sub 0.6}CoO{sub 2}. • The hydrothermal synthesis of P3-Na{sub 0.6}CoO{sub 2} involves one step and low temperature. • The yield diagram for Na–Co–H{sub 2}O system has been builded up to 250 °C. • We propose a formation mechanism of P3-Na{sub 0.6}CoO{sub 2} phase using the unit cell theory. • The thermal stability of P3-Na{sub 0.6}CoO{sub 2} has been investigated by means of HT-XRD. - Abstract: In order to obtain the layered sodium cobalt oxide materials by hydrothermal synthesis, the yield diagram for Na–Co–H{sub 2}O system has been built and studied. In the same time, the well-known data of Co–H{sub 2}O system have been extended at 250 °C in basic solution. We had first synthesized directly the high temperature stable phase, P3-Na{sub 0.6}CoO{sub 2} by a one-step low-temperature hydrothermal method. The rhombohedral structure of P3-Na{sub 0.6}CoO{sub 2} has been determined by X-ray diffraction (XRD) and the purity of phases has been confirmed by XPS. The thermal stability of P3-Na{sub 0.6}CoO{sub 2} has been investigated by means of high temperature X-ray diffraction in 298–873 K range and when the temperature has reached 723 K, the completely transformation of P3-Na{sub 0.6}CoO{sub 2} in the rhombohedral stable phase α-NaCoO{sub 2} (space group R-3m) was observed. Also, a formation mechanism of P3-Na{sub 0.6}CoO{sub 2} phase using the unit cell theory in the hydrothermal process was proposed.

  17. Experimental investigation of supersonic low pressure air plasma flows obtained with different arc-jet operating conditions

    SciTech Connect (OSTI)

    Lago, Viviana; Ndiaye, Abdoul-Aziz

    2012-11-27

    A stationary arc-jet plasma flow at low pressure is used to simulate some properties of the gas flow surrounding a vehicle during its entry into celestial body's atmospheres. This paper presents an experimental study concerning plasmas simulating a re-entry into our planet. Optical measurements have been carried out for several operating plasma conditions in the free stream, and in the shock layer formed in front of a flat cylindrical plate, placed in the plasma jet. The analysis of the spectral radiation enabled the identification of the emitting species, the determination of the rotational and vibrational temperatures in the free-stream and in the shock layer and the determination of the distance of the shock to the flat plate face. Some plasma fluid parameters like, stagnation pressure, specific enthalpy and heat flux have been determined experimentally along the plasma-jet axis.

  18. Electrolytic process to produce sodium hypochlorite using sodium ion conductive ceramic membranes

    DOE Patents [OSTI]

    Balagopal, Shekar; Malhotra, Vinod; Pendleton, Justin; Reid, Kathy Jo

    2012-09-18

    An electrochemical process for the production of sodium hypochlorite is disclosed. The process may potentially be used to produce sodium hypochlorite from seawater or low purity un-softened or NaCl-based salt solutions. The process utilizes a sodium ion conductive ceramic membrane, such as membranes based on NASICON-type materials, in an electrolytic cell. In the process, water is reduced at a cathode to form hydroxyl ions and hydrogen gas. Chloride ions from a sodium chloride solution are oxidized in the anolyte compartment to produce chlorine gas which reacts with water to produce hypochlorous and hydrochloric acid. Sodium ions are transported from the anolyte compartment to the catholyte compartment across the sodium ion conductive ceramic membrane. Sodium hydroxide is transported from the catholyte compartment to the anolyte compartment to produce sodium hypochlorite within the anolyte compartment.

  19. Effect of silicon on ultra-low temperature toughness of Nb–Ti microalloyed cryogenic pressure vessel steels

    SciTech Connect (OSTI)

    Qiu, J.A.; Wu, K.M.; Li, J.H.; Hodgson, P.D.; Hou, T.P.; Ding, Q.F.

    2013-09-15

    The effect of Si on the ultra-low temperature toughness of Nb–Ti microalloyed cryogenic pressure vessel steels was investigated by electron back-scattered diffraction and transmission electron microscope with energy dispersive spectroscopy. Equiaxed ferrite and bainite were obtained in the tempered steels with small Si additions. Nanosized Nb–Ti carbides (< 10 nm) were formed in the steel containing 0.05% Si, whereas much coarser carbides (> 30 nm) were found in the steel containing 0.47% Si. The ultra-low temperature toughness of the Nb–Ti microalloyed cryogenic pressure vessel steel was remarkably enhanced by the reduction in the Si content, which was attributed to the pre-existing iron carbide formation before the precipitation of nanosized Nb–Ti carbides during tempering. - Highlights: • Nanosized Nb-Ti carbides formed in the tempered steel with smaller Si addition. • Coarser Nb-Ti carbides formed in the tempered steel with more Si addition. • Pre-existing cememtites provide nucleation sites for Nb-Ti carbide precipitation. • Ultra-low temperature toughness was remarkably enhanced by Si content reduction.

  20. Position reconstruction in fission fragment detection using the low pressure MWPC technique for the JLab experiment E02-017

    SciTech Connect (OSTI)

    Xi-Yu, Qiu; Tang, Liguang; Margaryan, Amur T.; Jin-Zhang, Xu; Bi-Tao, Hu; Xi-Meng, Chen

    2014-07-01

    When a lambda hyperon was embedded in a nucleus, it can form a hypernucleus. The lifetime and its mass dependence of stable hypernuclei provide information about the weak decay of lambda hyperon inside nuclear medium. This work will introduce the Jefferson Lab experiment (E02-017) which aims to study the lifetime of the heavy hypernuclei using a specially developed fission fragment detection technique, a multi-wire proportional chamber operated under low gas pressure (LPMWPC). Presented here are the method and performance of the reconstruction of fission position on the target foil, the separation of target materials at different regions and the comparison and verification with the Mote Carlo simulation.

  1. Hydrogen generation systems and methods utilizing sodium silicide and sodium silica gel materials

    DOE Patents [OSTI]

    Wallace, Andrew P.; Melack, John M.; Lefenfeld, Michael

    2015-08-11

    Systems, devices, and methods combine thermally stable reactant materials and aqueous solutions to generate hydrogen and a non-toxic liquid by-product. The reactant materials can sodium silicide or sodium silica gel. The hydrogen generation devices are used in fuels cells and other industrial applications. One system combines cooling, pumping, water storage, and other devices to sense and control reactions between reactant materials and aqueous solutions to generate hydrogen. Springs and other pressurization mechanisms pressurize and deliver an aqueous solution to the reaction. A check valve and other pressure regulation mechanisms regulate the pressure of the aqueous solution delivered to the reactant fuel material in the reactor based upon characteristics of the pressurization mechanisms and can regulate the pressure of the delivered aqueous solution as a steady decay associated with the pressurization force. The pressure regulation mechanism can also prevent hydrogen gas from deflecting the pressure regulation mechanism.

  2. Critical Heat Flux Phenomena at HighPressure & Low Mass Fluxes: NEUP Final Report Part I: Experiments

    SciTech Connect (OSTI)

    Corradini, Michael; Wu, Qiao

    2015-04-30

    This report is a preliminary document presenting an overview of the Critical Heat Flux (CHF) phenomenon, the High Pressure Critical Heat Flux facility (HPCHF), preliminary CHF data acquired, and the future direction of the research. The HPCHF facility has been designed and built to study CHF at high pressure and low mass flux ranges in a rod bundle prototypical of conceptual Small Modular Reactor (SMR) designs. The rod bundle is comprised of four electrically heated rods in a 2x2 square rod bundle with a prototypic chopped-cosine axial power profile and equipped with thermocouples at various axial and circumferential positions embedded in each rod for CHF detection. Experimental test parameters for CHF detection range from pressures of ~80 – 160 bar, mass fluxes of ~400 – 1500 kg/m2s, and inlet water subcooling from ~30 – 70°C. The preliminary data base established will be further extended in the future along with comparisons to existing CHF correlations, models, etc. whose application ranges may be applicable to the conditions of SMRs.

  3. Fuel Economy and Emissions Effects of Low Tire Pressure, Open Windows, Roof Top and Hitch-Mounted Cargo, and Trailer

    SciTech Connect (OSTI)

    Thomas, John F; Huff, Shean P; West, Brian H

    2014-01-01

    To quantify the fuel economy (FE) effect of some common vehicle accessories or alterations, a compact passenger sedan and a sport utility vehicle (SUV) were subjected to SAE J2263 coastdown procedures. Coastdowns were conducted with low tire pressure, all windows open, with a roof top or hitch-mounted cargo carrier, and with the SUV pulling an enclosed cargo trailer. From these coastdowns, vehicle dynamometer coefficients were developed which enabled the execution of vehicle dynamometer experiments to determine the effect of these changes on vehicle FE and emissions over standard drive cycles and at steady highway speeds. The FE penalty associated with the rooftop cargo box mounted on the compact sedan was as high as 25-27% at higher speeds, where the aerodynamic drag is most pronounced. For both vehicles, use of a hitch mounted cargo tray carrying a similar load resulted in very small FE penalties, unlike the rooftop cargo box. The results for the SUV pulling a 3500 pound enclosed cargo trailer were rather dramatic, resulting in FE penalties ranging from 30%, for the city cycle, to 50% at 80 mph, at which point significant CO generation indicated protective enrichment due to high load. Low tire pressure cases resulted in negligible to 10% FE penalty depending on the specific case and test point. Driving with all four windows open decreased FE by 4-8.5% for the compact sedan, and 1-4% for the SUV.

  4. Combining Feedback Absorption Spectroscopy, Amplified Resonance and Low Pressure Sampling for the Measurement of Nitrogen-Containing Compounds in Automotive Emissions

    Broader source: Energy.gov [DOE]

    Discusses a novel combination of multi-component scanning direct absorption spectroscopy, resonant cavity and low-pressure sampling to systematically improve the performance of a specific gas analyzer.

  5. Study on critical heat flux enhancement in flow boiling of SiC nano-fluids under low pressure and low flow conditions

    SciTech Connect (OSTI)

    Lee, S. W.; Park, S. D.; Kang, S.; Kim, S. M.; Seo, H.; Lee, D. W.; Bang, I. C.

    2012-07-01

    Critical heat flux (CHF) is the thermal limit of a phenomenon in which a phase change occurs during heating (such as bubbles forming on a metal surface used to heat water), which suddenly decreases the heat transfer efficiency, thus causing localized overheating of the heating surface. The enhancement of CHF can increase the safety margins and allow operation at higher heat fluxes; thus, it can increase the economy. A very interesting characteristics of nano-fluids is their ability to significantly enhance the CHF. nano-fluids are nano-technology-based colloidal dispersions engineered through stable suspending of nanoparticles. All experiments were performed in round tubes with an inner diameter of 0.01041 m and a length of 0.5 m under low pressure and low flow (LPLF) conditions at a fixed inlet temperature using water, 0.01 vol. % Al{sub 2}O{sub 3}/water and SiC/water nano-fluids. It was found that the CHF of the nano-fluids was enhanced and the CHF of the SiC/water nano-fluid was more enhanced than that of the Al{sub 2}O{sub 3}/water nano-fluid. (authors)

  6. The manufacture of replacement low pressure carrier casings and associated stationary guide vane blading through on site component sample measurement

    SciTech Connect (OSTI)

    Fraser, M.J.

    1996-12-31

    In today`s competitive utility market place, the manufacture of replacement components by alternate manufacturing has become an increasingly important available option for turbine operators seeking to achieve substantive cost and lead time reductions in spare part purchasing. Essential to this strategy--in the absence of a total redesign of the component(s) or their assemblies--is the provision or access to the selected alternate manufacture of the necessary sample parts. This paper details the manufacture by reverse engineering of 3 replacement low pressure carrier guide vane blade casings for a 60 MW steam turbine complete with their associated blading and ancillary parts where the necessary sample parts and assemblies could not be released from site due to outage constraints.

  7. Electron-drift detection using directional planar probes in a low-pressure coaxial surface-wave discharge

    SciTech Connect (OSTI)

    Letout, S.; Boisse-Laporte, C.; Alves, L. L.

    2006-12-11

    Directional planar probes are used to investigate the electron population in low-pressure (10-100 mTorr) coaxial surface-wave (2.45 GHz) discharges, considering the anisotropy possibly induced by a local plasma resonance. Probe characteristics exhibit a significant increase in the electronic current over a wide range of probe potentials, depending on radial position and direction of observation. Such behavior reveals the presence of highly anisotropic electrons. Experimental probe currents were simulated by considering multiple electron populations, with drifting Maxwellian velocity distributions. Results yield axial drift velocities corresponding to energies up to 30 eV for populations of only a few 10{sup -2} below the thermal background density.

  8. Low pressure CO₂ hydrogenation to methanol over gold nanoparticles activated on a CeOx/TiO₂ interface

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

    Yang, Xiaofang; Boscoboinik, J. Anibal; Kattel, Shyam; Senanayake, Sanjaya D.; Nie, Xiaowa; Graciani, Jesus; Rodriguez, Jose A.; Liu, Ping; Stacchiola, Dario J.; Chen, Jingguang G.

    2015-07-28

    Capture and recycling of CO₂ into valuable chemicals such as alcohols could help mitigate its emissions into the atmosphere. Due to its inert nature, the activation of CO₂ is a critical step in improving the overall reaction kinetics during its chemical conversion. Although pure gold is an inert noble metal and cannot catalyze hydrogenation reactions, it can be activated when deposited as nanoparticles on the appropriate oxide support. In this combined experimental and theoretical study, it is shown that an electronic polarization at the metal–oxide interface of Au nanoparticles anchored and stabilized on a CeOx/TiO₂ substrate generates active centers formore » CO₂ adsorption and its low pressure hydrogenation, leading to a higher selectivity toward methanol. In conclusion, this study illustrates the importance of localized electronic properties and structure in catalysis for achieving higher alcohol selectivity from CO₂ hydrogenation.« less

  9. Growth of selective tungsten films on self-aligned CoSi/sub 2/ by low pressure chemical vapor deposition

    SciTech Connect (OSTI)

    van der Putte, P.; Sadana, D.K.; Broadbent, E.K.; Morgan, A.E.

    1986-12-22

    The selective deposition of tungsten films onto CoSi/sub 2/ and onto Co by low pressure chemical vapor deposition and their material properties have been investigated with Auger electron spectroscopy, transmission electron microscopy, and Rutherford backscattering. When using WF/sub 6/ and H/sub 2/, uniformly thick tungsten films can be deposited onto CoSi/sub 2/ without substrate alteration. In patterned structures, however, void formation was found at the perimeters of CoSi/sub 2/ contacts to silicon, indicating encroachment of WF/sub 6/ down the edge of the silicide-Si interface. In WF/sub 6/ and Ar, the film thickness was limited to 10 nm and some Si was locally consumed from the upper part of the CoSi/sub 2/ film. Transmission electron diffraction showed evidence of Co/sub 2/Si formation in these areas.

  10. A Concept for a Low Pressure Noble Gas Fill Intervention in the IFE Fusion Test Facility (FTF) Target Chamber

    SciTech Connect (OSTI)

    Gentile, C. A.; Blanchard, W. R.; Kozub, T. A.; Aristova, M.; McGahan, C.; Natta, S.; Pagdon, K.; Zelenty, J.

    2010-01-14

    An engineering evaluation has been initiated to investigate conceptual engineering methods for implementing a viable gas shield strategy in the Fusion Test Facility (FTF) target chamber. The employment of a low pressure noble gas in the target chamber to thermalize energetic helium ions prior to interaction with the wall could dramatically increase the useful life of the first wall in the FTF reactor1. For the purpose of providing flexibility, two target chamber configurations are addressed: a five meter radius sphere and a ten meter radius sphere. Experimental studies at Nike have indicated that a low pressure, ambient gas resident in the target chamber during laser pulsing does not appear to impair the ability of laser light from illuminating targets2. In addition, current investigations into delivering, maintaining, and processing low pressure gas appear to be viable with slight modification to current pumping and plasma exhaust processing technologies3,4. Employment of a gas fill solution for protecting the dry wall target chamber in the FTF may reduce, or possibly eliminate the need for other attenuating technologies designed for keeping He ions from implanting in first wall structures and components. The gas fill concept appears to provide an effective means of extending the life of the first wall while employing mostly commercial off the shelf (COTS) technologies. Although a gas fill configuration may provide a methodology for attenuating damage inflicted on chamber surfaces, issues associated with target injection need to be further analyzed to ensure that the gas fill concept is viable in the integrated FTF design5. In the proposed system, the ambient noble gas is heated via the energetic helium ions produced by target detonation. The gas is subsequently cooled by the chamber wall to approximately 800oC, removed from the chamber, and processed by the chamber gas processing system (CGPS). In an optimized scenario of the above stated concept, the chamber

  11. Chemical structures of low-pressure premixed methylcyclohexane flames as benchmarks for the development of a predictive combustion chemistry model

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

    Skeen, Scott A.; Yang, Bin; Jasper, Ahren W.; Pitz, William J.; Hansen, Nils

    2011-11-14

    The chemical compositions of three low-pressure premixed flames of methylcyclohexane (MCH) are investigated with the emphasis on the chemistry of MCH decomposition and the formation of aromatic species, including benzene and toluene. The flames are stabilized on a flat-flame (McKenna type) burner at equivalence ratios of φ = 1.0, 1.75, and 1.9 and at low pressures between 15 Torr (= 20 mbar) and 30 Torr (= 40 mbar). The complex chemistry of MCH consumption is illustrated in the experimental identification of several C7H12, C7H10, C6H12, and C6H10 isomers sampled from the flames as a function of distance from the burner.more » Three initiation steps for MCH consumption are discussed: ring-opening to heptenes and methyl-hexenes (isomerization), methyl radical loss yielding the cyclohexyl radical (dissociation), and H abstraction from MCH. Mole fraction profiles as a function of distance from the burner for the C7 species supplemented by theoretical calculations are presented, indicating that flame structures resulting in steeper temperature gradients and/or greater peak temperatures can lead to a relative increase in MCH consumption through the dissociation and isomerization channels. Trends observed among the stable C6 species as well as 1,3-pentadiene and isoprene also support this conclusion. Relatively large amounts of toluene and benzene are observed in the experiments, illustrating the importance of sequential H-abstraction steps from MCH to toluene and from cyclohexyl to benzene. Furthermore, modeled results using the detailed chemical model of Pitz et al. (Proc. Combust. Inst.2007, 31, 267–275) are also provided to illustrate the use of these data as a benchmark for the improvement or future development of a MCH mechanism.« less

  12. Final Report DE-FG02-00ER54583: "Physics of Atmospheric Pressure Glow Discharges" and "Nanoparticle Nucleation and Dynamics in Low-Pressure Plasmas"

    SciTech Connect (OSTI)

    Uwe Kortshagen; Joachim Heberlein; Steven L. Girshick

    2009-06-01

    This project was funded over two periods of three years each, with an additional year of no-cost extension. Research in the first funding period focused on the physics of uniform atmospheric pressure glow discharges, the second funding period was devoted to the study of the dynamics of nanometer-sized particles in plasmas.

  13. Sodium cobalt bronze batteries and a method for making same

    DOE Patents [OSTI]

    Doeff, Marca M.; Ma, Yanping; Visco, Steven J.; DeJonghe, Lutgard

    1999-01-01

    A solid state secondary battery utilizing a low cost, environmentally sound, sodium cobalt bronze electrode. A method is provided for producing same.

  14. Sodium cobalt bronze batteries and a method for making same

    DOE Patents [OSTI]

    Doeff, M.M.; Ma, Y.; Visco, S.J.; DeJonghe, L.

    1999-06-29

    A solid state secondary battery utilizing a low cost, environmentally sound, sodium cobalt bronze electrode is described. A method is provided for producing same. 11 figs.

  15. Numerical study of effect of secondary electron emission on discharge characteristics in low pressure capacitive RF argon discharge

    SciTech Connect (OSTI)

    Liu, Qian; Liu, Yue, E-mail: liuyue@dlut.edu.cn; Samir, Tagra; Ma, Zhaoshuai [Key Laboratory of Materials Modification by Laser, Ion and Electron Beams, Ministry of Education, School of Physics and Optoelectronic Technology, Dalian University of Technology, Dalian 116024 (China)

    2014-08-15

    Based on the drift and diffusion approximation theory, a 1D fluid model on capacitively coupled RF argon glow discharge at low pressure is established to study the effect of secondary electron emission (SEE) on the discharge characteristics. The model is numerically solved by using a finite difference method and the numerical results are obtained. The numerical results indicate that when the SEE coefficient is larger, the plasma density is higher and the time of reaching steady state is longer. It is also found that the cycle-averaged electric field, electric potential, and electron temperature change a little as the SEE coefficient is increased. Moreover, the discharge characteristics in some nonequilibrium discharge processes with different SEE coefficients have been compared. The analysis shows that when the SEE coefficient is varied from 0.01 to 0.3, the cycle-averaged electron net power absorption, electron heating rate, thermal convective term, electron energy dissipation, and ionization all have different degrees of growth. While the electron energy dissipation and ionization are quite special, there appear two peaks near each sheath region in the discharge with a relatively larger SEE coefficient. In this case, the discharge is certainly operated in a hybrid ?-?-mode.

  16. Gasoline from coal in the state of Illinois: feasibility study. Volume I. Design. [KBW gasification process, ICI low-pressure methanol process and Mobil M-gasoline process

    SciTech Connect (OSTI)

    Not Available

    1980-01-01

    Volume 1 describes the proposed plant: KBW gasification process, ICI low-pressure methanol process and Mobil M-gasoline process, and also with ancillary processes, such as oxygen plant, shift process, RECTISOL purification process, sulfur recovery equipment and pollution control equipment. Numerous engineering diagrams are included. (LTN)

  17. Method of preparing silicon from sodium fluosilicate

    DOE Patents [OSTI]

    Schmidt, Frederick A.; Rehbein, David; Chiotti, Premo

    1984-01-01

    A process for preparing high purity silicon metal from Na.sub.2 SiF.sub.6 (sodium fluosilicate). The sodium fluosilicate is heated to decomposition temperature to form NaF, which retains most of the impurities, and gaseous SiF.sub.4. The SiF.sub.4 is then reduced by the bomb reduction method using a reductant having a low packing density.

  18. Energy absorber for sodium-heated heat exchanger

    DOE Patents [OSTI]

    Essebaggers, J.

    1975-12-01

    A heat exchanger is described in which water-carrying tubes are heated by liquid sodium and in which the results of accidental contact between the water and the sodium caused by failure of one or more of the water tubes is minimized. An energy absorbing chamber contains a compressible gas and is connected to the body of flowing sodium by a channel so that, in the event of a sodium-water reaction, products of the reaction will partially fill the energy absorbing chamber to attenuate the rise in pressure within the heat exchanger.

  19. HOx radical chemistry in oxidation flow reactors with low-pressure mercury lamps systematically examined by modeling

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

    Peng, Z.; Day, D. A.; Stark, H.; Li, R.; Palm, B. B.; Brune, W. H.; Jimenez, J. L.

    2015-04-20

    Oxidation flow reactors (OFRs) using OH produced from low-pressure Hg lamps at 254 nm (OFR254) or both 185 and 254 nm (OFR185) are commonly used in atmospheric chemistry and other fields. OFR254 requires the addition of externally formed O3 since OH is formed from O3 photolysis, while OFR185 does not since O2 can be photolyzed to produce O3 and OH can also be formed from H2O photolysis. In this study, we use a plug-flow kinetic model to investigate OFR properties under a very wide range of conditions applicable to both field and laboratory studies. We show that the radical chemistrymore » in OFRs can be characterized as a function of UV light intensity, H2O concentration, and total external OH reactivity (OHRext, e.g., from VOCs, NOx, and SO2). OH exposure is decreased by added external OH reactivity. OFR185 is especially sensitive to this effect at low UV intensity due to low primary OH production. OFR254 can be more resilient against OH suppression at high injected O3 (e.g., 70 ppm), as a larger primary OH source from O3, as well as enhanced recycling of HO2 to OH, make external perturbations to the radical chemistry less significant. However if the external OH reactivity in OFR254 is much larger than OH reactivity from injected O3, OH suppression can reach two orders of magnitude. For a typical input of 7 ppm O3 (OHRO3 = 10 s−1) ten-fold OH suppression is observed at OHRext ∼ 100 s−1, which is similar or lower than used in many laboratory studies. This finding may have important implications for the interpretation of past laboratory studies, as applying OHexp measurements acquired under different conditions could lead to over an order-of-magnitude error in the estimated OHexp. The uncertainties of key model outputs due to uncertainty in all rate constants and absorption cross-sections in the model are within ± 25% for OH exposure and within ± 60% for other parameters. These uncertainties are small relative to the dynamic range of outputs. Uncertainty

  20. Low temperature carrier transport study of monolayer MoS{sub 2} field effect transistors prepared by chemical vapor deposition under an atmospheric pressure

    SciTech Connect (OSTI)

    Liu, Xinke E-mail: wujing026@gmail.com; He, Jiazhu; Tang, Dan; Lu, Youming; Zhu, Deliang; Liu, Wenjun; Cao, Peijiang; Han, Sun; Liu, Qiang; Wen, Jiao; Yu, Wenjie; Liu, Wenjun; Wu, Jing E-mail: wujing026@gmail.com; He, Zhubing; Ang, Kah-Wee

    2015-09-28

    Large size monolayer Molybdenum disulphide (MoS{sub 2}) was successfully grown by chemical vapor deposition method under an atmospheric pressure. The electrical transport properties of the fabricated back-gate monolayer MoS{sub 2} field effect transistors (FETs) were investigated under low temperatures; a peak field effect mobility of 59 cm{sup 2}V{sup −1}s{sup −1} was achieved. With the assist of Raman measurement under low temperature, this work identified the mobility limiting factor for the monolayer MoS{sub 2} FETs: homopolar phonon scattering under low temperature and electron-polar optical phonon scattering at room temperature.

  1. Test plan for glass melter system technologies for vitrification of high-sodium content low-level radioactive liquid waste, Project No. RDD-43288

    SciTech Connect (OSTI)

    Higley, B.A.

    1995-03-15

    This document provides a test plan for the conduct of combustion fired cyclone vitrification testing by a vendor in support of the Hanford Tank Waste Remediation System, Low-Level Waste Vitrification Program. The vendor providing this test plan and conducting the work detailed within it is the Babcock & Wilcox Company Alliance Research Center in Alliance, Ohio. This vendor is one of seven selected for glass melter testing.

  2. SOLAR RADIATION PRESSURE AND LOCAL INTERSTELLAR MEDIUM FLOW PARAMETERS FROM INTERSTELLAR BOUNDARY EXPLORER LOW ENERGY HYDROGEN MEASUREMENTS

    SciTech Connect (OSTI)

    Schwadron, N. A.; Moebius, E.; Kucharek, H.; Lee, M. A.; French, J.; Saul, L.; Wurz, P.; Bzowski, M.; Fuselier, S. A.; Livadiotis, G.; McComas, D. J.; Frisch, P.; Gruntman, M.; Mueller, H. R.

    2013-10-01

    Neutral hydrogen atoms that travel into the heliosphere from the local interstellar medium (LISM) experience strong effects due to charge exchange and radiation pressure from resonant absorption and re-emission of Ly?. The radiation pressure roughly compensates for the solar gravity. As a result, interstellar hydrogen atoms move along trajectories that are quite different than those of heavier interstellar species such as helium and oxygen, which experience relatively weak radiation pressure. Charge exchange leads to the loss of primary neutrals from the LISM and the addition of new secondary neutrals from the heliosheath. IBEX observations show clear effects of radiation pressure in a large longitudinal shift in the peak of interstellar hydrogen compared with that of interstellar helium. Here, we compare results from the Lee et al. interstellar neutral model with IBEX-Lo hydrogen observations to describe the distribution of hydrogen near 1 AU and provide new estimates of the solar radiation pressure. We find over the period analyzed from 2009 to 2011 that radiation pressure divided by the gravitational force (?) has increased slightly from ? = 0.94 0.04 in 2009 to ? = 1.01 0.05 in 2011. We have also derived the speed, temperature, source longitude, and latitude of the neutral H atoms and find that these parameters are roughly consistent with those of interstellar He, particularly when considering the filtration effects that act on H in the outer heliosheath. Thus, our analysis shows that over the period from 2009 to 2011, we observe signatures of neutral H consistent with the primary distribution of atoms from the LISM and a radiation pressure that increases in the early rise of solar activity.

  3. Evidence of the existence of the high-density and low-density phases in deeply-cooled confined heavy water under high pressures

    SciTech Connect (OSTI)

    Wang, Zhe; Chen, Sow-Hsin; Liu, Kao-Hsiang; Harriger, Leland; Leo, Juscelino B.

    2014-07-07

    The average density of D{sub 2}O confined in a nanoporous silica matrix (MCM-41-S) is studied with neutron scattering. We find that below ?210 K, the pressure-temperature plane of the system can be divided into two regions. The average density of the confined D{sub 2}O in the higher-pressure region is about 16% larger than that in the lower-pressure region. These two regions could represent the so-called low-density liquid and high-density liquid phases. The dividing line of these two regions, which could represent the associated 1st order liquid-liquid transition line, is also determined.

  4. Submersible sodium pump

    DOE Patents [OSTI]

    Brynsvold, G.V.; Lopez, J.T.; Olich, E.E.; West, C.W.

    1989-11-21

    An electromagnetic submerged pump has an outer cylindrical stator with an inner cylindrical conductive core for the submerged pumping of sodium in the cylindrical interstitial volume defined between the stator and core. The cylindrical interstitial volume is typically vertically oriented, and defines an inlet at the bottom and an outlet at the top. The outer stator generates upwardly conveyed toroidal magnetic fields, which fields convey preferably from the bottom of the pump to the top of the pump liquid sodium in the cold leg of a sodium cooled nuclear reactor. The outer cylindrical stator has a vertically disposed duct surrounded by alternately stacked layers of coil units and laminates. 14 figs.

  5. Submersible sodium pump

    DOE Patents [OSTI]

    Brynsvold, Glen V.; Lopez, John T.; Olich, Eugene E.; West, Calvin W.

    1989-01-01

    An electromagnetic submerged pump has an outer cylindrical stator with an inner cylindrical conductive core for the submerged pumping of sodium in the cylindrical interstitial volume defined between the stator and core. The cylindrical interstitial volume is typically vertically oriented, and defines an inlet at the bottom and an outlet at the top. The outer stator generates upwardly conveyed toroidal magnetic fields, which fields convey preferably from the bottom of the pump to the top of the pump liquid sodium in the cold leg of a sodium cooled nuclear reactor. The outer cylindrical stator has a vertically disposed duct surrounded by alternately stacked layers of coil units and laminates.

  6. Test plan for evaluation of plasma melter technology for vitrification of high-sodium content low-level radioactive liquid wastes

    SciTech Connect (OSTI)

    McLaughlin, D.F.; Lahoda, E.J.; Gass, W.R.; D`Amico, N.

    1994-10-20

    This document provides a test plan for the conduct of plasma arc vitrification testing by a vendor in support of the Hanford Tank Waste Remediation System (TWRS) Low-Level Waste (LLW) Vitrification Program. The vendor providing this test plan and conducting the work detailed within it [one of seven selected for glass melter testing under Purchase Order MMI-SVV-384212] is the Westinghouse Science and Technology Center (WSTC) in Pittsburgh, PA. WSTC authors of the test plan are D. F. McLaughlin, E. J. Lahoda, W. R. Gass, and N. D`Amico. The WSTC Program Manager for this test is D. F. McLaughlin. This test plan is for Phase I activities described in the above Purchase Order. Test conduct includes melting of glass frit with Hanford LLW Double-Shell Slurry Feed waste simulant in a plasma arc fired furnace.

  7. Test Plan: Phase 1 demonstration of 3-phase electric arc melting furnace technology for vitrifying high-sodium content low-level radioactive liquid wastes

    SciTech Connect (OSTI)

    Eaton, W.C.

    1995-05-31

    This document provides a test plan for the conduct of electric arc vitrification testing by a vendor in support of the Hanford Tank Waste Remediation System (TWRS) Low-Level Waste (LLW) Vitrification Program. The vendor providing this test plan and conducting the work detailed within it [one of seven selected for glass melter testing under Purchase Order MMI-SVV-384216] is the US Bureau of Mines, Department of the Interior, Albany Research Center, Albany, Oregon. This test plan is for Phase I activities described in the above Purchase Order. Test conduct includes feed preparation activities and melting of glass with Hanford LLW Double-Shell Slurry Feed waste simulant in a 3-phase electric arc (carbon electrode) furnace.

  8. HOx radical chemistry in oxidation flow reactors with low-pressure mercury lamps systematically examined by modeling

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

    Peng, Z.; Day, D. A.; Stark, H.; Li, R.; Lee-Taylor, J.; Palm, B. B.; Brune, W. H.; Jimenez, J. L.

    2015-11-20

    Oxidation flow reactors (OFRs) using OH produced from low-pressure Hg lamps at 254 nm (OFR254) or both 185 and 254 nm (OFR185) are commonly used in atmospheric chemistry and other fields. OFR254 requires the addition of externally formed O3 since OH is formed from O3 photolysis, while OFR185 does not since O2 can be photolyzed to produce O3, and OH can also be formed from H2O photolysis. In this study, we use a plug-flow kinetic model to investigate OFR properties under a very wide range of conditions applicable to both field and laboratory studies. We show that the radical chemistrymore » in OFRs can be characterized as a function of UV light intensity, H2O concentration, and total external OH reactivity (OHRext, e.g., from volatile organic compounds (VOCs), NOx, and SO2). OH exposure is decreased by added external OH reactivity. OFR185 is especially sensitive to this effect at low UV intensity due to low primary OH production. OFR254 can be more resilient against OH suppression at high injected O3 (e.g., 70 ppm), as a larger primary OH source from O3, as well as enhanced recycling of HO2 to OH, make external perturbations to the radical chemistry less significant. However if the external OH reactivity in OFR254 is much larger than OH reactivity from injected O3, OH suppression can reach 2 orders of magnitude. For a typical input of 7 ppm O3 (OHRO3 = 10 s−1), 10-fold OH suppression is observed at OHRext ~ 100 s−1, which is similar or lower than used in many laboratory studies. The range of modeled OH suppression for literature experiments is consistent with the measured values except for those with isoprene. The finding on OH suppression may have important implications for the interpretation of past laboratory studies, as applying OHexp measurements acquired under different conditions could lead to over a 1-order-of-magnitude error in the estimated OHexp. The uncertainties of key model outputs due to uncertainty in all rate constants and absorption cross

  9. Analysis of a high pressure ATWS (anticipated transient without scram) with very low make-up flow

    SciTech Connect (OSTI)

    Wagner, K.C.

    1988-10-01

    A series of calculations were performed to analyze the response of General Electric Company's (GE) advanced boiling water reactor (ABWR) during an anticipated transient without scram (ATWS). This work investigated the early plant response with an assumed failure or manual inhibit of the high pressure core flooder (HPCF). Consequently, the reactor core isolation cooling (RCIC) and control rod drive (CRD) systems are the only sources of high pressure injection available to maintain core cooling. Steam leaving the reactor pressure vessel was diverted to the pressure suppression pool (PSP) via the steam line and the safety relief valves. The combination of an unscrammed core and the CRD and RCIC injection sources make this a particularly challenging transient. System energy balance calculations were performed to predict the core power and PSP heat-up rate. The amount of vessel vapor superheat and the PSP temperature were found to significantly affect the resultant core power. Consequently, detailed thermal-hydraulic calculations were performed to simulate the system response during the postulated transient. 15 refs., 15 figs., 4 tabs.

  10. Liquid-sodium thermoacoustic engine

    SciTech Connect (OSTI)

    Migliori, A.; Swift, G.W.

    1988-08-01

    We have constructed a thermoacoustic engine that uses liquid sodium as its working substance. The engine generates acoustic power using heat flowing from a high-temperature source to a low-temperature sink. The measured performance of this engine disagrees significantly with numerical calculations based on our theory of thermoacoustic engines. The efficiency of the engine is a substantial fraction of Carnot's efficiency, and its power density is comparable to that of the conventional heat engines in widespread use. Thus we expect this type of engine to be of practical, economic importance.

  11. Infrared spectroscopic and modeling studies of H{sub 2}/CH{sub 4} microwave plasma gas phase from low to high pressure and power

    SciTech Connect (OSTI)

    Rond, C. Lombardi, G.; Gicquel, A.; Hamann, S.; Rpcke, J.; Wartel, M.

    2014-09-07

    InfraRed Tunable Diode Laser Absorption Spectroscopy technique has been implemented in a H{sub 2}/CH{sub 4} Micro-Wave (MW frequency f?=?2.45 GHz) plasma reactor dedicated to diamond deposition under high pressure and high power conditions. Parametric studies such as a function of MW power, pressure, and admixtures of methane have been carried out on a wide range of experimental conditions: the pressure up to 270 mbar and the MW power up to 4?kW. These conditions allow high purity Chemical Vapor Deposition diamond deposition at high growth rates. Line integrated absorption measurements have been performed in order to monitor hydrocarbon species, i.e., CH{sub 3}, CH{sub 4}, C{sub 2}H{sub 2}, C{sub 2}H{sub 4}, and C{sub 2}H{sub 6}. The densities of the stable detected species were found to vary in the range of 10{sup 12}10{sup 17} molecules cm{sup ?3}, while the methyl radical CH{sub 3} (precursor of diamond growth under these conditions) measured into the plasma bulk was found up to 10{sup 14} molecules cm{sup ?3}. The experimental densities have been compared to those provided by 1D-radial thermochemical model for low power and low pressure conditions (up to 100 mbar/2?kW). These densities have been axially integrated. Experimental measurements under high pressure and power conditions confirm a strong increase of the degree of dissociation of the precursor, CH{sub 4}, associated to an increase of the C{sub 2}H{sub 2} density, the most abundant reaction product in the plasma.

  12. Sodium-sulfur thermal battery

    SciTech Connect (OSTI)

    Ludwig, F.A.

    1990-12-11

    This paper discusses a sodium-sulfur thermal battery for generating electrical energy at temperatures above the melting point of sodium metal and sulfur. It comprises a sodium electrode comprising sodium metal; a sulfur electrode comprising sulfur; and a separator located between the sodium and sulfur electrodes. The separator having sufficient porosity to allow preliminary migration of fluid sodium metal and fluid sulfur and fluid sodium polysulfides therethrough during operation of the thermal battery to form a mixed polysulfides electrolyte gradient within the separator.

  13. Computer analysis of sodium cold trap design and performance. [LMFBR

    SciTech Connect (OSTI)

    McPheeters, C.C.; Raue, D.J.

    1983-11-01

    Normal steam-side corrosion of steam-generator tubes in Liquid Metal Fast Breeder Reactors (LMFBRs) results in liberation of hydrogen, and most of this hydrogen diffuses through the tubes into the heat-transfer sodium and must be removed by the purification system. Cold traps are normally used to purify sodium, and they operate by cooling the sodium to temperatures near the melting point, where soluble impurities including hydrogen and oxygen precipitate as NaH and Na/sub 2/O, respectively. A computer model was developed to simulate the processes that occur in sodium cold traps. The Model for Analyzing Sodium Cold Traps (MASCOT) simulates any desired configuration of mesh arrangements and dimensions and calculates pressure drops and flow distributions, temperature profiles, impurity concentration profiles, and impurity mass distributions.

  14. Use Steam Jet Ejectors or Thermoscompressors to Reduce Venting of Low-Pressure Steam - Steam Tip Sheet #29

    SciTech Connect (OSTI)

    2012-01-01

    This revised AMO tip sheet on steam jet ejectors and thermocompressors provides how-to advice for improving industrial steam systems using low-cost, proven practices and technologies.

  15. Super-radiance in the sodium resonance lines from sodium iodide arc lamps

    SciTech Connect (OSTI)

    Karabourniotis, D.; Drakakis, E.

    2010-08-09

    Super-radiance observed within the centers of the sodium resonance D lines emitted by arc lamps containing sodium iodide as additive in a high-pressure mercury plasma environment was studied by high-resolution emission spectroscopy. The spectral radiance of these self-reversed lines including super-radiance was simulated by considering a local enhancement of the source function due to the presence of an additional source of radiation near the arc wall. Causes of this hitherto unrecognized source of radiation are given.

  16. Atmospheric pressure plasma chemical vapor deposition reactor for 100 mm wafers, optimized for minimum contamination at low gas flow rates

    SciTech Connect (OSTI)

    Anand, Venu E-mail: venuanand83@gmail.com; Shivashankar, S. A.; Nair, Aswathi R.; Mohan Rao, G.

    2015-08-31

    Gas discharge plasmas used for thinfilm deposition by plasma-enhanced chemical vapor deposition (PECVD) must be devoid of contaminants, like dust or active species which disturb the intended chemical reaction. In atmospheric pressure plasma systems employing an inert gas, the main source of such contamination is the residual air inside the system. To enable the construction of an atmospheric pressure plasma (APP) system with minimal contamination, we have carried out fluid dynamic simulation of the APP chamber into which an inert gas is injected at different mass flow rates. On the basis of the simulation results, we have designed and built a simple, scaled APP system, which is capable of holding a 100 mm substrate wafer, so that the presence of air (contamination) in the APP chamber is minimized with as low a flow rate of argon as possible. This is examined systematically by examining optical emission from the plasma as a function of inert gas flow rate. It is found that optical emission from the plasma shows the presence of atmospheric air, if the inlet argon flow rate is lowered below 300 sccm. That there is minimal contamination of the APP reactor built here, was verified by conducting an atmospheric pressure PECVD process under acetylene flow, combined with argon flow at 100 sccm and 500 sccm. The deposition of a polymer coating is confirmed by infrared spectroscopy. X-ray photoelectron spectroscopy shows that the polymer coating contains only 5% of oxygen, which is comparable to the oxygen content in polymer deposits obtained in low-pressure PECVD systems.

  17. Method of making a sodium sulfur battery

    DOE Patents [OSTI]

    Elkins, P. E.

    1981-09-22

    A method of making a portion of a sodium sulfur battery is disclosed. The battery portion made is a portion of the container which defines the volume for the cathodic reactant materials which are sulfur and sodium polysulfide materials. The container portion is defined by an outer metal casing with a graphite liner contained therein, the graphite liner having a coating on its internal diameter for sealing off the porosity thereof. The steel outer container and graphite pipe are united by a method which insures that at the operating temperature of the battery, relatively low electrical resistance exists between the two materials because they are in intimate contact with one another. 3 figs.

  18. Method of making a sodium sulfur battery

    DOE Patents [OSTI]

    Elkins, Perry E.

    1981-01-01

    A method of making a portion of a sodium sulfur battery is disclosed. The battery portion made is a portion of the container which defines the volume for the cathodic reactant materials which are sulfur and sodium polysulfide materials. The container portion is defined by an outer metal casing with a graphite liner contained therein, the graphite liner having a coating on its internal diameter for sealing off the porosity thereof. The steel outer container and graphite pipe are united by a method which insures that at the operating temperature of the battery, relatively low electrical resistance exists between the two materials because they are in intimate contact with one another.

  19. Sodium-tetravalent sulfur molten chloroaluminate cell

    DOE Patents [OSTI]

    Mamantov, Gleb (Knoxville, TN)

    1985-04-02

    A sodium-tetravalent sulfur molten chloroaluminate cell with a .beta."-alumina sodium ion conductor having a S-Al mole ratio of above about 0.15 in an acidic molten chloroaluminate cathode composition is disclosed. The cathode composition has an AlCl.sub.3 -NaCl mole percent ratio of above about 70-30 at theoretical full charge. The cell provides high energy densities at low temperatures and provides high energy densities and high power densities at moderate temperatures.

  20. Comparison of MELCOR and SCDAP/RELAP5 results for a low-pressure, short-term station blackout at Browns Ferry

    SciTech Connect (OSTI)

    Carbajo, J.J. [Oak Ridge National Lab., TN (United States)

    1995-12-31

    This study compares results obtained with two U.S. Nuclear Regulatory Commission (NRC)-sponsored codes, MELCOR version 1.8.3 (1.8PQ) and SCDAP/RELAP5 Mod3.1 release C, for the same transient - a low-pressure, short-term station blackout accident at the Browns Ferry nuclear plant. This work is part of MELCOR assessment activities to compare core damage progression calculations of MELCOR against SCDAP/RELAP5 since the two codes model core damage progression very differently.

  1. Sodium sulfur battery seal

    DOE Patents [OSTI]

    Topouzian, Armenag

    1980-01-01

    This invention is directed to a seal for a sodium sulfur battery in which a flexible diaphragm sealing elements respectively engage opposite sides of a ceramic component of the battery which separates an anode compartment from a cathode compartment of the battery.

  2. Elastic properties, sp³ fraction, and Raman scattering in low and high pressure synthesized diamond-like boron rich carbides

    SciTech Connect (OSTI)

    Zinin, Pavel V.; Burgess, Katherine; Jia, Ruth; Sharma, Shiv; Ming, Li-Chung; Liu, Yongsheng; Ciston, Jim; Hong, Shiming

    2014-10-07

    Dense BC{sub x} phases with high boron concentration are predicted to be metastable, superhard, and conductors or superconductors depending on boron concentration. However, up to this point, diamond-like boron rich carbides BC{sub x} (dl-BC{sub x}) phases have been thought obtainable only through high pressure and high temperature treatment, necessitating small specimen volume. Here, we use electron energy loss spectroscopy combined with transmission electron microscopy, Raman spectroscopy, surface Brillouin scattering, laser ultrasonics (LU) technique, and analysis of elastic properties to demonstrate that low pressure synthesis (chemical vapor deposition) of BC{sub x} phases may also lead to the creation of diamond-like boron rich carbides. The elastic properties of the dl-BC{sub x} phases depend on the carbon sp²versus sp³ content, which decreases with increasing boron concentration, while the boron bonds determine the shape of the Raman spectra of the dl-BC{sub x} after high pressure-high temperature treatment. Using the estimation of the density value based on the sp³ fraction, the shear modulus μ of dl-BC₄, containing 10% carbon atoms with sp³ bonds, and dl-B₃C₂, containing 38% carbon atoms with sp³ bonds, were found to be μ = 19.3 GPa and μ = 170 GPa, respectively. The presented experimental data also imply that boron atoms lead to a creation of sp³ bonds during the deposition processes.

  3. Three-electrode low pressure discharge apparatus and method for uniform ionization of gaseous media. [CO/sub 2/ laser oscillator and pulse smoother

    DOE Patents [OSTI]

    McLellan, E.J.

    1980-10-17

    Uniform, transverse electrical discharges are produced in gaseous media without the necessity of switching the main discharge voltage with an external device which carries the entire discharge current. A three-electrode low pressure discharge tube is charged across its anode and cathode to below breakdown voltage using a dc voltage source. An array of resistors or capacitors can be made to discharge to the wire screen anode by means of a low energy high voltage pulse circuit producing sufficient preionization in the region between the anode and cathode to initiate and control the main discharge. The invention has been demonstrated to be useful as a CO/sub 2/ laser oscillator and pulse-smoother. It can be reliably operated in the sealed-off mode.

  4. Enhancing Magnesite Formation at Low Temperature and High CO2 Pressure: The Impact of Seed Crystals and Minor Components

    SciTech Connect (OSTI)

    Felmy, Andrew R.; Qafoku, Odeta; Arey, Bruce W.; Kovarik, Libor; Liu, Jia; Perea, Daniel E.; Ilton, Eugene S.

    2015-02-24

    The formation of magnesite was followed in aqueous solution containing initially added Mg(OH)2 equilibrated with supercritical carbon dioxide (90 atm pressure, 50C) in the presence of introduced magnesite particles and minor components, Co(II). As expected, the introduction of magnesite particles accelerated the formation of magnesite from solution. However, the formation rate of magnesite was even greater when small concentrations of Co(II) were introduced, indicating that the increased rate of magnesite formation in the presence of Co(II) was not solely due to the addition of a growth promoting surface. Detailed analysis of the magnesite particles by scanning electron microscopy (SEM), transmission electron microscopy (TEM), energy dispersive spectroscopy (EDS), and atom probe tomography (APT) revealed that the originally added Co(II) was concentrated in the center but also present throughout the growing magnesite particles. Addition of the Co(II) in different chemical forms (i.e. as solid phase CoCO3 or Co(OH)2) could alter the growth rate of magnesite depending upon the addition of bicarbonate to the starting solution. Geochemical modeling calculations indicate that this difference is related to the thermodynamic stability of these different phases in the initial solutions. More broadly, these results indicate that the presence of even small concentrations of foreign ions that form carbonate compounds with a similar structure as magnesite can be incorporated into the magnesite lattice, accelerating the formation of anhydrous carbonates in natural environments.

  5. Energy and environmental research emphasizing low-rank coal -- Task 3.8, Pressurized fluidized-bed combustion

    SciTech Connect (OSTI)

    Mann, M.D.; Henderson, A.K.; Swanson, M.L.

    1995-03-01

    The goal of the PFBC activity is to generate fundamental process information that will further the development of an economical and environmentally acceptable second-generation PFBC. The immediate objectives focus on generic issues, including the performance of sulfur sorbents, fate of alkali, and the Resource Conservation and Recovery Act (RCRA) heavy metals in PFBC. A great deal of PFBC performance relates to the chemistry of the bed and the contact between gas and solids that occurs during combustion. These factors can be studied in a suitably designed bench-scale reactor. The present studies are focusing on the emission control strategies applied in the bed, rather than in hot-gas cleaning. Emission components include alkali and heavy metals in addition to SO{sub 2}, NO{sub x}, N{sub 2}O, and CO. The report presents: a description of the pressurized fluidized-bed reactor (PFBR); a description of the alkali sampling probe; shakedown testing of the bench-scale PFBR; results from alkali sampling; results from sulfur sorbent performance tests; and results from refuse-derived fuel and lignite combustion tests.

  6. The physical nature of the phenomenon of positive column plasma constriction in low-pressure noble gas direct current discharges

    SciTech Connect (OSTI)

    Kurbatov, P. F.

    2014-02-15

    The essence of the positive-column plasma constriction for static (the diffusion mode) and dynamic ionization equilibrium (the stratificated and constricted modes) is analyzed. Two physical parameters, namely, the effective ionization rate of gas atoms and the ambipolar diffusion coefficient of electrons and ions, determine the transverse distribution of discharge species and affect the current states of plasma. Transverse constriction of the positive column takes place as the gas ionization level (discharge current) and pressure increase. The stratified mode (including the constricted one) is observed between the two adjacent types of self-sustained discharge phases when they coexist together at the same time or in the same place as a coherent binary mixture. In the case, a occurrence of the discharge phase with more high electron density presently involve a great decrease in the cross-section of the current channel for d.c. discharges. Additional physical factors, such as cataphoresis and electrophoresis phenomena and spatial gas density inhomogeneity correlated with a circulatory flow in d.c. discharges, are mainly responsible for the current hysteresis and partially constricted discharge.

  7. A low-power pressure-and temperature-programmed separation system for a micro gas chromatograph.

    SciTech Connect (OSTI)

    Sacks, Richard D. (University of Michigan, Ann Arbor, MI); Robinson, Alex Lockwood (Advanced Sensor Technologies, Albuquerque, NM); Lambertus, Gordon R. (University of Michigan, Ann Arbor, MI); Potkay, Joseph A. (University of Michigan, Ann Arbor, MI); Wise, Kensall D. (University of Michigan, Ann Arbor, MI)

    2006-10-01

    This thesis presents the theory, design, fabrication and testing of the microvalves and columns necessary in a pressure- and temperature-programmed micro gas chromatograph ({micro}GC). Two microcolumn designs are investigated: a bonded Si-glass column having a rectangular cross section and a vapor-deposited silicon oxynitride (Sion) column having a roughly circular cross section. Both microcolumns contain integrated heaters and sensors for rapid, controlled heating. The 3.2 cm x 3.2 cm, 3 m-long silicon-glass column, coated with a non-polar polydimethylsiloxane (PDMS) stationary phase, separates 30 volatile organic compounds (VOCs) in less than 6 min. This is the most efficient micromachined column reported to date, producing greater than 4000 plates/m. The 2.7 mm x 1.4 mm Sion column eliminates the glass sealing plate and silicon substrate using deposited dielectrics and is the lowest power and fastest GC column reported to date; it requires only 11 mW to raise the column temperature by 100 C and has a response time of 11s and natural temperature ramp rate of 580 C/min. A 1 m-long PDMS-coated Sion microcolumn separates 10 VOCs in 52s. A system-based design approach was used for both columns.

  8. Conceptual Engineering Method for Attenuating He Ion Interactions on First Wall Components in the Fusion Test Facility (FTF) Employing a Low-Pressure Noble Gas

    SciTech Connect (OSTI)

    C.A.Gentile, W.R.Blanchard, T.Kozub, C.Priniski, I.Zatz, S.Obenschain

    2009-09-21

    It has been shown that post detonation energetic helium ions can drastically reduce the useful life of the (dry) first wall of an IFE reactor due to the accumulation of implanted helium. For the purpose of attenuating energetic helium ions from interacting with first wall components in the Fusion Test Facility (FTF) target chamber, several concepts have been advanced. These include magnetic intervention (MI), deployment of a dynamically moving first wall, use of a sacrificial shroud, designing the target chamber large enough to mitigate the damage caused by He ions on the target chamber wall, and the use of a low pressure noble gas resident in the target chamber during pulse power operations. It is proposed that employing a low-pressure (~ 1 torr equivalent) noble gas in the target chamber will thermalize energetic helium ions prior to interaction with the wall. The principle benefit of this concept is the simplicity of the design and the utilization of (modified) existing technologies for pumping and processing the noble ambient gas. Although the gas load in the system would be increased over other proposed methods, the use of a "gas shield" may provide a cost effective method of greatly extending the first wall of the target chamber. An engineering study has been initiated to investigate conceptual engineering metmethods for implementing a viable gas shield strategy in the FTF.

  9. Aquion Energy Inc Sodium-ion Battery for Grid-level Applications

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

    Aquion Energy Inc Sodium-ion Battery for Grid-level Applications Project Description Aquion Energy and its partners will demonstrate a low cost, grid-scale, ambient temperature sodium-ion energy storage device. The energy storage chemistry in this device uses an electrochemical couple that combines a high capacity carbon anode with a sodium intercalation cathode capable of thousands of deep discharge cycles over extended periods of time. The proposed aqueous sodium-ion technology includes the

  10. Study of metallic powder behavior in very low pressure plasma spraying (VLPPS) — Application to the manufacturing of titanium–aluminum coatings

    SciTech Connect (OSTI)

    Vautherin, B.; Planche, M.-P.; Montavon, G.; Lapostolle, F.; Quet, A.; Bianchi, L.

    2015-08-28

    In this study, metallic materials made of aluminum and titanium were manufactured implementing very low pressure plasma spraying (VLPPS). Aluminum was selected at first as a demonstrative material due to its rather low vaporization enthalpy (i.e., 381.9 kJ·mol⁻¹). Developments were then carried out with titanium which exhibits a higher vaporization enthalpy (i.e., 563.6 kJ·mol⁻¹). Optical emission spectroscopy (OES) was implemented to analyze the behavior of each solid precursor (metallic powders) when it is injected into the plasma jet under very low pressure (i.e., in the 150 Pa range). Besides, aluminum, titanium and titanium–aluminum coatings were deposited in the same conditions implementing a stick-cathode plasma torch operated at 50 kW, maximum power. Coating phase compositions were identified by X-Ray Diffraction (XRD). Coating elementary compositions were quantified by Glow Discharge Optical Emission Spectroscopy (GDOES) and Energy Dispersive Spectroscopy (EDS) analyses. The coating structures were observed by Scanning Electron Microscopy (SEM). The coating void content was determined by Ultra-Small Angle X-ray Scattering (USAXS). The coatings exhibit a two-scale structure corresponding to condensed vapors (smaller scale) and solidified areas (larger scale). Titanium–aluminum sprayed coatings, with various Ti/Al atomic ratios, are constituted of three phases: metastable α-Ti, Al and metastable α₂-Ti₃Al. This latter is formed at elevated temperature in the plasma flow, before being condensed. Its rather small fraction, impeded by the rather small amount of vaporized Ti, does not allow modifying however the coating hardness.

  11. Miniaturized pressurization system

    DOE Patents [OSTI]

    Whitehead, John C. (Davis, CA); Swink, Don G. (Woodinville, WA)

    1991-01-01

    The invention uses a fluid stored at a low pressure and provides the fluid at a high pressure. The invention allows the low pressure fluid to flow to a fluid bore of a differential pump and from the pump to a fluid pressure regulator. After flowing through the regulator the fluid is converted to a gas which is directed to a gas bore of the differential pump. By controlling the flow of gas entering and being exhausted from the gas bore, the invention provides pressure to the fluid. By setting the regulator, the high pressure fluid can be set at predetermined values. Because the invention only needs a low pressure fluid, the inventive apparatus has a low mass, and therefore would be useful in rocket propulsion systems.

  12. Improving the homogeneity of alternating current-drive atmospheric pressure dielectric barrier discharges in helium with an additional low-amplitude radio frequency power source: A numerical study

    SciTech Connect (OSTI)

    Wang Qi [Dalian Institute of Semiconductor Technology, School of Electronics Science and Technology, Dalian University of Technology, Dalian 116023 (China); Sun Jizhong; Zhang Jianhong; Wang Dezhen [School of Physics and Optoelectronic Technology, Dalian University of Technology, Dalian 116023 (China); Liu Liying [Department of Electrical Engineering, Shenyang Institute of Engineering, Shenyang 110136 (China)

    2013-04-15

    It was proposed in this paper that the homogeneity of the atmospheric pressure discharge driven by an ac power source could be improved by applying an auxiliary low-amplitude rf power source. To verify the idea, a two-dimensional fluid model then was applied to study the atmospheric discharges in helium driven by ac power, low-amplitude rf power, and combined ac and low-amplitude rf power, respectively. Simulation results confirmed that an auxiliary rf power could improve the homogeneity of a discharge driven by an ac power source. It was further found that there existed a threshold voltage of the rf power source leading to the transition from inhomogeneous to homogeneous discharge. As the frequency of the rf power source increased from 2 to 22 MHz, the magnitude of the threshold voltage dropped first rapidly and then to a constant value. When the frequency was over 13.56 MHz, the magnitude of the threshold voltage was smaller than one-sixth of the ac voltage amplitude under the simulated discharge parameters.

  13. Containment failure time and mode for a low-pressure short-term station blackout in a BWR-4 with Mark-I containment

    SciTech Connect (OSTI)

    Carbajo, J.J.; Greene, S.R. (Oak Ridge National Lab., TN (United States))

    1993-01-01

    This study investigates containment failure time and mode for a low-pressure, short-term station blackout severe accident sequence in a boiling water reactor (BWR-4) with a Mark-I containment. The severe accident analysis code MELCOR, version 1.8.1, was used in these calculations. Other results using the MELCOR/CORBH package and the BWRSAR and CONTAIN codes are also presented and compared to the MELCOR results. The plant analyzed is the Peach Bottom atomic station, a BWR-4 with a Mark-I containment. The automatic depressurization system was used to depressurize the vessel in accordance with the Emergency Procedure Guidelines. Two different variations of the station blackout were studied: one with a dry cavity and the other with a flooded cavity. For the flooded cavity, it is assumed that a control rod drive (CRD) pump becomes operational after vessel failure, and it is used to pump water into the cavity.

  14. Identification of combustion intermediates in a low-pressure premixed laminar 2,5-dimethylfuran/oxygen/argon flame with tunable synchrotron photoionization

    SciTech Connect (OSTI)

    Wu, Xuesong; Huang, Zuohua; Wei, Lixia [State Key Laboratory of Multiphase Flow in Power Engineering, Xi'an Jiaotong University, Xi'an 710049 (China); Yuan, Tao; Zhang, Kuiwen [National Synchrotron Radiation Laboratory, University of Science and Technology of China, Hefei 230029 (China)

    2009-07-15

    Low-pressure (4.0 kPa) premixed laminar 2,5-dimethylfuran (DMF)/oxygen/argon flame with an equivalence ratio of 2.0 was studied with tunable vacuum ultraviolet (VUV) synchrotron radiation photoionization and molecular-beam mass spectrometry. Photoionization mass spectra of DMF/O{sub 2}/Ar flame were recorded and the photoionization efficiency curves of the combustion intermediates were measured. Flame species, including isomeric intermediates, are identified by comparing the measured ionization energies with those reported in literatures or those calculated with Gaussian-3 procedure. More than 70 species have been detected, including furan and its derivatives, aromatics, and free radicals. Possible reaction pathways of DMF, 2-methylfuran, and furan are proposed based on the intermediates identified. DMF can be consumed by H-abstraction and pyrolysis reactions. 2-Methylfuran and furan can be consumed by H-abstraction, H-addition and pyrolysis reactions. (author)

  15. Low pressure CO₂ hydrogenation to methanol over gold nanoparticles activated on a CeOx/TiO₂ interface

    SciTech Connect (OSTI)

    Yang, Xiaofang; Boscoboinik, J. Anibal; Kattel, Shyam; Senanayake, Sanjaya D.; Nie, Xiaowa; Graciani, Jesus; Rodriguez, Jose A.; Liu, Ping; Stacchiola, Dario J.; Chen, Jingguang G.

    2015-07-28

    Capture and recycling of CO₂ into valuable chemicals such as alcohols could help mitigate its emissions into the atmosphere. Due to its inert nature, the activation of CO₂ is a critical step in improving the overall reaction kinetics during its chemical conversion. Although pure gold is an inert noble metal and cannot catalyze hydrogenation reactions, it can be activated when deposited as nanoparticles on the appropriate oxide support. In this combined experimental and theoretical study, it is shown that an electronic polarization at the metal–oxide interface of Au nanoparticles anchored and stabilized on a CeOx/TiO₂ substrate generates active centers for CO₂ adsorption and its low pressure hydrogenation, leading to a higher selectivity toward methanol. In conclusion, this study illustrates the importance of localized electronic properties and structure in catalysis for achieving higher alcohol selectivity from CO₂ hydrogenation.

  16. Low pressure CO? hydrogenation to methanol over gold nanoparticles activated on a CeOx/TiO? interface

    SciTech Connect (OSTI)

    Yang, Xiaofang; Boscoboinik, J. Anibal; Kattel, Shyam; Senanayake, Sanjaya D.; Nie, Xiaowa; Graciani, Jesus; Rodriguez, Jose A.; Liu, Ping; Stacchiola, Dario J.; Chen, Jingguang G.

    2015-07-28

    Capture and recycling of CO? into valuable chemicals such as alcohols could help mitigate its emissions into the atmosphere. Due to its inert nature, the activation of CO? is a critical step in improving the overall reaction kinetics during its chemical conversion. Although pure gold is an inert noble metal and cannot catalyze hydrogenation reactions, it can be activated when deposited as nanoparticles on the appropriate oxide support. In this combined experimental and theoretical study, it is shown that an electronic polarization at the metaloxide interface of Au nanoparticles anchored and stabilized on a CeOx/TiO? substrate generates active centers for CO? adsorption and its low pressure hydrogenation, leading to a higher selectivity toward methanol. In conclusion, this study illustrates the importance of localized electronic properties and structure in catalysis for achieving higher alcohol selectivity from CO? hydrogenation.

  17. Low temperature, low pressure hydrogen gettering

    DOE Patents [OSTI]

    Anderson, D. Richard; Courtney, Robert L.; Harrah, Larry A.

    1976-06-15

    The invention relates to the gettering of hydrogen and its isotopes, the gettering materials being painted or coated onto, or otherwise disposed in an area or volume from which hydrogen is to be removed.

  18. Low temperature, low pressure hydrogen gettering

    DOE Patents [OSTI]

    Anderson, D.R.; Courtney, R.L.; Harrah, L.A.

    1975-07-22

    A system is described for the gettering of hydrogen and its isotopes. The gettering materials are painted or coated onto, or otherwise disposed in an area or volume from which hydrogen is to be removed. (auth)

  19. Corrosion performance of advanced structural materials in sodium.

    SciTech Connect (OSTI)

    Natesan, K.; Momozaki, Y.; Li, M.; Rink, D.L.

    2012-05-16

    This report gives a description of the activities in design, fabrication, construction, and assembling of a pumped sodium loop for the sodium compatibility studies on advanced structural materials. The work is the Argonne National Laboratory (ANL) portion of the effort on the work project entitled, 'Sodium Compatibility of Advanced Fast Reactor Materials,' and is a part of Advanced Materials Development within the Reactor Campaign. The objective of this project is to develop information on sodium corrosion compatibility of advanced materials being considered for sodium reactor applications. This report gives the status of the sodium pumped loop at Argonne National Laboratory, the specimen details, and the technical approach to evaluate the sodium compatibility of advanced structural alloys. This report is a deliverable from ANL in FY2010 (M2GAN10SF050302) under the work package G-AN10SF0503 'Sodium Compatibility of Advanced Fast Reactor Materials.' Two reports were issued in 2009 (Natesan and Meimei Li 2009, Natesan et al. 2009) which examined the thermodynamic and kinetic factors involved in the purity of liquid sodium coolant for sodium reactor applications as well as the design specifications for the ANL pumped loop for testing advanced structural materials. Available information was presented on solubility of several metallic and nonmetallic elements along with a discussion of the possible mechanisms for the accumulation of impurities in sodium. That report concluded that the solubility of many metals in sodium is low (<1 part per million) in the temperature range of interest in sodium reactors and such trace amounts would not impact the mechanical integrity of structural materials and components. The earlier report also analyzed the solubility and transport mechanisms of nonmetallic elements such as oxygen, nitrogen, carbon, and hydrogen in laboratory sodium loops and in reactor systems such as Experimental Breeder Reactor-II, Fast Flux Test Facility, and

  20. Sodium to sodium carbonate conversion process

    DOE Patents [OSTI]

    Herrmann, S.D.

    1997-10-14

    A method is described for converting radioactive alkali metal into a low level disposable solid waste material. The radioactive alkali metal is atomized and introduced into an aqueous caustic solution having caustic present in the range of from about 20 wt % to about 70 wt % to convert the radioactive alkali metal to a radioactive alkali metal hydroxide. The aqueous caustic containing radioactive alkali metal hydroxide and CO{sub 2} are introduced into a thin film evaporator with the CO{sub 2} present in an amount greater than required to convert the alkali metal hydroxide to a radioactive alkali metal carbonate, and thereafter the radioactive alkali metal carbonate is separated from the thin film evaporator as a dry powder. Hydroxide solutions containing toxic metal hydroxide including one or more metal ions of Sb, As, Ba, Be, Cd, Cr, Pb, Hg, Ni, Se, Ag and Tl can be converted into a low level non-hazardous waste using the thin film evaporator of the invention. 3 figs.

  1. Sodium to sodium carbonate conversion process

    DOE Patents [OSTI]

    Herrmann, Steven D.

    1997-01-01

    A method of converting radioactive alkali metal into a low level disposable solid waste material. The radioactive alkali metal is atomized and introduced into an aqueous caustic solution having caustic present in the range of from about 20 wt % to about 70 wt % to convert the radioactive alkali metal to a radioactive alkali metal hydroxide. The aqueous caustic containing radioactive alkali metal hydroxide and CO.sub.2 are introduced into a thin film evaporator with the CO.sub.2 present in an amount greater than required to convert the alkali metal hydroxide to a radioactive alkali metal carbonate, and thereafter the radioactive alkali metal carbonate is separated from the thin film evaporator as a dry powder. Hydroxide solutions containing toxic metal hydroxide including one or more metal ions of Sb, As, Ba, Be, Cd, Cr, Pb, Hg, Ni, Se, Ag and T1 can be converted into a low level non-hazardous waste using the thin film evaporator of the invention.

  2. Hydrogen generation systems utilizing sodium silicide and sodium silica gel materials

    DOE Patents [OSTI]

    Wallace, Andrew P.; Melack, John M.; Lefenfeld, Michael

    2015-07-14

    Systems, devices, and methods combine reactant materials and aqueous solutions to generate hydrogen. The reactant materials can sodium silicide or sodium silica gel. The hydrogen generation devices are used in fuels cells and other industrial applications. One system combines cooling, pumping, water storage, and other devices to sense and control reactions between reactant materials and aqueous solutions to generate hydrogen. Multiple inlets of varied placement geometries deliver aqueous solution to the reaction. The reactant materials and aqueous solution are churned to control the state of the reaction. The aqueous solution can be recycled and returned to the reaction. One system operates over a range of temperatures and pressures and includes a hydrogen separator, a heat removal mechanism, and state of reaction control devices. The systems, devices, and methods of generating hydrogen provide thermally stable solids, near-instant reaction with the aqueous solutions, and a non-toxic liquid by-product.

  3. Investigation of the effects of a thin dielectric layer on low-pressure hydrogen capacitive discharges driven by combined radio frequency and pulse power sources

    SciTech Connect (OSTI)

    Sun, Jizhong; Fan, Yu; Zou, Ying; Wang, Dezhen; Stirner, Thomas

    2013-11-15

    Negative hydrogen ion sources, for instance for fusion devices, currently attract considerable attention. To generate the precursors—highly rovibrationally excited hydrogen molecules—for negative hydrogen ions effectively by electron excitation, a thin dielectric layer is introduced to cover the surface of the electrically grounded electrode of two parallel metal plates in a low-pressure hydrogen capacitive discharge driven by combined rf and pulse power sources. To understand the characteristics of such discharges, particle-in-cell simulations are conducted to study the effects that the single dielectric layer would bring onto the discharges. The simulation results show that the dielectric layer leads to a much higher plasma density and a much larger production rate of highly vibrationally excited hydrogen molecules compared to discharges without the dielectric layer on the electrode. Further investigation indicates that the nonlinear oscillation of the electrons induced by the nanosecond-pulse continues until it is finally damped down and does not show any dependence on the pulse plateau-time, which is in stark contrast to the case without the dielectric layer present. The physical reason for this phenomenon is explored and explained.

  4. Sodium Recycle Economics for Waste Treatment Plant Operations

    SciTech Connect (OSTI)

    Sevigny, Gary J.; Poloski, Adam P.; Fountain, Matthew S.

    2008-08-31

    Sodium recycle at the Hanford Waste Treatment Plant (WTP) would reduce the number of glass canisters produced, and has the potential to significantly reduce the cost to the U.S. Department of Energy (DOE) of treating the tank wastes by hundreds of millions of dollars. The sodium, added in the form of sodium hydroxide, was originally added to minimize corrosion of carbon-steel storage tanks from acidic reprocessing wastes. In the baseline Hanford treatment process, sodium hydroxide is required to leach gibbsite and boehmite from the high level waste (HLW) sludge. In turn, this reduces the amount of HLW glass produced. Currently, a significant amount of additional sodium hydroxide will be added to the process to maintain aluminate solubility at ambient temperatures during ion exchange of cesium. The vitrification of radioactive waste is limited by sodium content, and this additional sodium mass will increase low-activity waste-glass mass. An electrochemical salt-splitting process, based on sodium-ion selective ceramic membranes, is being developed to recover and recycle sodium hydroxide from high-salt radioactive tank wastes in DOEs complex. The ceramic membranes are from a family of materials known as sodium (Na)super-ionic conductors (NaSICON)and the diffusion of sodium ions (Na+) is allowed, while blocking other positively charged ions. A cost/benefit evaluation was based on a strategy that involves a separate caustic-recycle facility based on the NaSICON technology, which would be located adjacent to the WTP facility. A Monte Carlo approach was taken, and several thousand scenarios were analyzed to determine likely economic results. The cost/benefit evaluation indicates that 10,00050,000 metric tons (MT) of sodium could be recycled, and would allow for the reduction of glass production by 60,000300,000 MT. The cost of the facility construction and operation was scaled to the low-activity waste (LAW) vitrification facility, showing cost would be roughly $150

  5. Independent Oversight Review, Sodium Bearing Waste Treatment...

    Office of Environmental Management (EM)

    Independent Oversight Review, Sodium Bearing Waste Treatment Project - Contractor - June 2012 June 2012 Review of the Sodium Bearing Waste Treatment Project - Integrated Waste ...

  6. Low-activation-energy conduction in polycrystalline. cap alpha. -Al/sub 2/O/sub 3/ doped with Si and Na

    SciTech Connect (OSTI)

    Lee, C.H.; Kroger, F.A.

    1985-02-01

    Polycrystalline Al/sub 2/O/sub 3/ containing a glassy aluminosilicate second phase displays a low-activation-energy conductivity when Na is present. The conductivity is ionic in nature at high oxygen pressure and electronic at low oxygen pressure and is attributed to the migration of Na/sup +/ ions and electrons through the second phase present at triple junctions. A smaller lowactivation-energy conductivity is found in the absence of sodium, but in that case the low-activation-energy branch has different properties. Al/sub 2/O/sub 3/:Na without silicon has no lowtemperature low-activation-energy branch.

  7. Rhombohedral Prussian White as Cathode for Rechargeable Sodium-Ion Batteries

    SciTech Connect (OSTI)

    Wang, L; Song, J; Qiao, RM; Wray, LA; Hossain, MA; Chuang, YD; Yang, WL; Lu, YH; Evans, D; Lee, JJ; Vail, S; Zhao, X; Nishijima, M; Kakimoto, S; Goodenough, JB

    2015-02-25

    A novel air-stable sodium iron hexacyanoferrate (R-Na1.92Fe[Fe(CN)(6)]) with rhombohedral structure is demonstrated to be a scalable, low-cost cathode material for sodium-ion batteries exhibiting high capacity, long cycle life, and good rate capability. The cycling mechanism of the iron redox is clarified and understood through synchrotron-based soft X-ray absorption spectroscopy, which also reveals the correlation between the physical properties and the cell performance of this novel material. More importantly, successful preparation of a dehydrated iron hexacyanoferrate with high sodium-ion concentration enables the fabrication of a discharged sodium-ion battery with a non-sodium metal anode, and the manufacturing feasibility of low cost sodium-ion batteries with existing lithium-ion battery infrastructures has been tested.

  8. Pressure Systems

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

    Engineering > Pressure Systems Privacy and Security Notice Skip over navigation Search the JLab Site Pressure Systems Please upgrade your browser. This site's design is only ...

  9. Low-pressure hydrogen discharge maintenance in a large-size plasma source with localized high radio-frequency power deposition

    SciTech Connect (OSTI)

    Todorov, D.; Shivarova, A. Paunska, Ts.; Tarnev, Kh.

    2015-03-15

    The development of the two-dimensional fluid-plasma model of a low-pressure hydrogen discharge, presented in the study, is regarding description of the plasma maintenance in a discharge vessel with the configuration of the SPIDER source. The SPIDER source, planned for the neutral-beam-injection plasma-heating system of ITER, is with localized high RF power deposition to its eight drivers (cylindrical-coil inductive discharges) and a large-area second chamber, common for all the drivers. The continuity equations for the charged particles (electrons and the three types of positive ions) and for the neutral species (atoms and molecules), their momentum equations, the energy balance equations for electrons, atoms and molecules and the Poisson equations are involved in the discharge description. In addition to the local processes in the plasma volume, the surface processes of particle reflection and conversion on the walls as well as for a heat exchange with the walls are included in the model. The analysis of the results stresses on the role of the fluxes (particle and energy fluxes) in the formation of the discharge structure. The conclusion is that the discharge behavior is completely obeyed to non-locality. The latter is displayed by: (i) maximum values of plasma parameters (charged particle densities and temperatures of the neutral species) outside the region of the RF power deposition, (ii) shifted maxima of the electron density and temperature, of the plasma potential and of the electron production, (iii) an electron flux, with a vortex structure, strongly exceeding the total ion flux which gives evidence of a discharge regime of non-ambipolarity and (iv) a spatial distribution of the densities of the neutral species resulting from their fluxes.

  10. Hybrid Pressure Retarded Osmosis-Membrane Distillation System for Power Generation from Low-Grade Heat: Thermodynamic Analysis and Energy Efficiency

    SciTech Connect (OSTI)

    Lin, SH; Yip, NY; Cath, TY; Osuji, CO; Elimelech, M

    2014-05-06

    We present a novel hybrid membrane system that operates as a heat engine capable of utilizing low-grade thermal energy, which is not readily recoverable with existing technologies. The closed-loop system combines membrane distillation (MD), which generates concentrated and pure water streams by thermal separation, and pressure retarded osmosis (PRO), which converts the energy of mixing to electricity by a hydro-turbine. The PRO-MD system was modeled by coupling the mass and energy flows between the thermal separation (MD) and power generation (PRO) stages for heat source temperatures ranging from 40 to 80 degrees C and working concentrations of 1.0, 2.0, and 4.0 mol/kg NaCl. The factors controlling the energy efficiency of the heat engine were evaluated for both limited and unlimited mass and heat transfer kinetics in the thermal separation stage. In both cases, the relative flow rate between the MD permeate (distillate) and feed streams is identified as an important operation parameter. There is an optimal relative flow rate that maximizes the overall energy efficiency of the PRO-MD system for given working temperatures and concentration. In the case of unlimited mass and heat transfer kinetics, the energy efficiency of the system can be analytically determined based on thermodynamics. Our assessment indicates that the hybrid PRO-MD system can theoretically achieve an energy efficiency of 9.8% (81.6% of the Carnot efficiency) with hot and cold working temperatures of 60 and 20 degrees C, respectively, and a working solution of 1.0 M NaCl. When mass and heat transfer kinetics are limited, conditions that more closely represent actual operations, the practical energy efficiency will be lower than the theoretically achievable efficiency. In such practical operations, utilizing a higher working concentration will yield greater energy efficiency. Overall, our study demonstrates the theoretical viability of the PRO-MD system and identifies the key factors for

  11. High temperature pressure gauge

    DOE Patents [OSTI]

    Echtler, J. Paul; Scandrol, Roy O.

    1981-01-01

    A high temperature pressure gauge comprising a pressure gauge positioned in fluid communication with one end of a conduit which has a diaphragm mounted in its other end. The conduit is filled with a low melting metal alloy above the diaphragm for a portion of its length with a high temperature fluid being positioned in the remaining length of the conduit and in the pressure gauge.

  12. Bag pressure monitor

    DOE Patents [OSTI]

    Vaughn, Mark Roy; Miller, Alva Keith

    2000-01-01

    An inexpensive mechanical indicator for measuring low pressure in an inflating bag includes a pair of sides connected to each other at one edge and pivotally connected at spaced parallel locations on the bag. A spring biases the sides towards each other in opposition to tension in the inflating bag. The distance between the sides is indicative of the pressure in the bag. The device is accurate at pressures below 0.05 psi.

  13. Sodium removal process development for LMFBR fuel subassemblies

    SciTech Connect (OSTI)

    Simmons, C.R.; Taylor, G.R.

    1981-10-01

    Two 37-pin scale models of Clinch River Breeder Reactor Plant fuel subassemblies were designed, fabricated and used at Westinghouse Advanced Reactors Division in the development and proof-testing of a rapid water-based sodium removal process for the ORNL Hot Experimental Facility, Liquid Metal Fast Breeder Reactor Fuel Reprocessing Cycle. Through a series of development tests on one of the models, including five (5) sodium wettings and three (3) high temperature sodium removal operations, optimum process parameters for a rapid water vapor-argon-water rinse process were identified and successfully proof-tested on a second model containing argon-pressurized, sodium-corroded model fuel pins simulating the gas plenum and cladding conditions expected for spent fuel pins in full scale subassemblies. Based on extrapolations of model proof test data, preliminary process parameters for a water vapor-nitrogen-water rinse process were calculated and recommended for use in processing full scale fuel subassemblies in the Sodium Removal Facility of the Fuel Receiving Cell, ORNL HEF.

  14. Changes in mineralogical and leaching properties of converter steel slag resulting from accelerated carbonation at low CO{sub 2} pressure

    SciTech Connect (OSTI)

    Zomeren, Andre van; Laan, Sieger R. van der; Kobesen, Hans B.A.; Huijgen, Wouter J.J.; Comans, Rob N.J.

    2011-11-15

    Highlights: > Accelerated carbonation studied to improve environmental properties of steel slag. > Carbonation found to occur predominantly at surface of the steel slag grains. > Combined geochemical modelling and mineral analysis revealed controlling processes. > Enhanced V-leaching with di-Ca silicate (C2S) dissolution identified as major source. > Identified mineral transformations provide guidance for further quality improvement. - Abstract: Steel slag can be applied as substitute for natural aggregates in construction applications. The material imposes a high pH (typically 12.5) and low redox potential (Eh), which may lead to environmental problems in specific application scenarios. The aim of this study is to investigate the potential of accelerated steel slag carbonation, at relatively low pCO{sub 2} pressure (0.2 bar), to improve the environmental pH and the leaching properties of steel slag, with specific focus on the leaching of vanadium. Carbonation experiments are performed in laboratory columns with steel slag under water-saturated and -unsaturated conditions and temperatures between 5 and 90 {sup o}C. Two types of steel slag are tested; free lime containing (K3) slag and K1 slag with a very low free lime content. The fresh and carbonated slag samples are investigated using a combination of leaching experiments, geochemical modelling of leaching mechanisms and microscopic/mineralogical analysis, in order to identify the major processes that control the slag pH and resulting V leaching. The major changes in the amount of sequestered CO{sub 2} and the resulting pH reduction occurred within 24 h, the free lime containing slag (K3-slag) being more prone to carbonation than the slag with lower free lime content (K1-slag). While carbonation at these conditions was found to occur predominantly at the surface of the slag grains, the formation of cracks was observed in carbonated K3 slag, suggesting that free lime in the interior of slag grains had also reacted

  15. Aqueous solutions database to high temperatures and pressures...

    Office of Scientific and Technical Information (OSTI)

    Title: Aqueous solutions database to high temperatures and pressures: NaCl solutions A survey is made of available experimental data on sodium chloride solutions which are used in ...

  16. Validation of CONTAIN-LMR code for accident analysis of sodium-cooled fast reactor containments

    SciTech Connect (OSTI)

    Gordeev, S.; Hering, W.; Schikorr, M.; Stieglitz, R.

    2012-07-01

    CONTAIN-LMR 1 is an analytical tool for the containment performance of sodium cooled fast reactors. In this code, the modelling for the sodium fire is included: the oxygen diffusion model for the sodium pool fire, and the liquid droplet model for the sodium spray fire. CONTAIN-LMR is also able to model the interaction of liquid sodium with concrete structure. It may be applicable to different concrete compositions. Testing and validation of these models will help to qualify the simulation results. Three experiments with sodium performed in the FAUNA facility at FZK have been used for the validation of CONTAIN-LMR. For pool fire tests, calculations have been performed with two models. The first model consists of one gas cell representing the volume of the burn compartment. The volume of the second model is subdivided into 32 coupled gas cells. The agreement between calculations and experimental data is acceptable. The detailed pool fire model shows less deviation from experiments. In the spray fire, the direct heating from the sodium burning in the media is dominant. Therefore, single cell modeling is enough to describe the phenomena. Calculation results have reasonable agreement with experimental data. Limitations of the implemented spray model can cause the overestimation of predicted pressure and temperature in the cell atmosphere. The ability of the CONTAIN-LMR to simulate the sodium pool fire accompanied by sodium-concrete reactions was tested using the experimental study of sodium-concrete interactions for construction concrete as well as for shielding concrete. The model provides a reasonably good representation of chemical processes during sodium-concrete interaction. The comparison of time-temperature profiles of sodium and concrete shows, that the model requires modifications for predictions of the test results. (authors)

  17. Ion Recognition Approach to Volume Reduction of Alkaline Tank Waste by Separation of Sodium Salts

    SciTech Connect (OSTI)

    Levitskaia, Tatiana G.; Lumetta, Gregg J.; Moyer, Bruce A.; Bonnesen, Peter V.

    2006-06-01

    The purpose of this research involving collaboration between Oak Ridge National Laboratory (ORNL) and Pacific Northwest National Laboratory (PNNL) is to explore new approaches to the separation of sodium hydroxide, sodium nitrate, and other sodium salts from high-level alkaline tank waste. The principal potential benefit is a major reduction in disposed waste volume, obviating the building of expensive new waste tanks and reducing the costs of low-activity waste immobilization. Principles of ion recognition are being researched toward discovery of liquid extraction systems that selectively separate sodium hydroxide and sodium nitrate from other waste components. The successful concept of pseudohydroxide extraction using fluorinated alcohols and phenols is being developed at ORNL and PNNL toward a greater understanding of the controlling equilibria, role of solvation, and of synergistic effects involving crown ethers. Studies at PNNL are directed toward new solvent formulation for the practical sodium pseudohydroxide extraction systems.

  18. Sodium Battery | GE Global Research

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

    Sodium Battery Technology Improves Performance and Safety Click to email this to a friend (Opens in new window) Share on Facebook (Opens in new window) Click to share (Opens in new window) Click to share on LinkedIn (Opens in new window) Click to share on Tumblr (Opens in new window) Sodium Battery Technology Improves Performance and Safety Imagination and innovation have always been in GE's DNA. While exploring the expanded use of hybrid power in the rail, mining and marine industries, GE began

  19. Development of a multiphysics analysis system for sodium-water reaction phenomena in steam generators of sodium-cooled fast reactors

    SciTech Connect (OSTI)

    Uchibori, Akihiro; Kurihara, Akikazu; Ohshima, Hiroyuki

    2015-12-31

    A multiphysics analysis system for sodium-water reaction phenomena in a steam generator of sodium-cooled fast reactors was newly developed. The analysis system consists of the mechanistic numerical analysis codes, SERAPHIM, TACT, and RELAP5. The SERAPHIM code calculates the multicomponent multiphase flow and sodium-water chemical reaction caused by discharging of pressurized water vapor. Applicability of the SERAPHIM code was confirmed through the analyses of the experiment on water vapor discharging in liquid sodium. The TACT code was developed to calculate heat transfer from the reacting jet to the adjacent tube and to predict the tube failure occurrence. The numerical models integrated into the TACT code were verified through some related experiments. The RELAP5 code evaluates thermal hydraulic behavior of water inside the tube. The original heat transfer correlations were corrected for the tube rapidly heated by the reacting jet. The developed system enables evaluation of the wastage environment and the possibility of the failure propagation.

  20. An empirical modeling approach to high sodium glass durability

    SciTech Connect (OSTI)

    Shine, E.P.; Sadler, A.L.K. [Westinghouse Savannah River Company, Aiken, SC (United States)

    1996-12-31

    Empirical mixture models have been developed for chemical durability of high sodium borosilicate glass. The response of boron to a seven-day Product Consistency Test (PCT) was chosen as the measure of durability. The objective of the model development was to support the proposed vitrification of Hanford low-level waste (LLW), the bulk of which is primarily sodium oxide. A full first-order model and a second order model were developed from a database of high-sodium borosilicate glasses. First-order models proved to be satisfactory in a qualitative sense, but root mean squared errors were fairly large for quantitative predictive purposes. The results imply that mechanistic models relating durability to composition should include higher order compositional interactions; a second-order model yielded much improved statistics. The modeling results also suggest that calcium, which is considered a network modifier yet is also regarded as a glass {open_quotes}stiffener{close_quotes}, may improve durability.

  1. Seal for sodium sulfur battery

    DOE Patents [OSTI]

    Topouzian, Armenag; Minck, Robert W.; Williams, William J.

    1980-01-01

    This invention is directed to a seal for a sodium sulfur battery in which the sealing is accomplished by a radial compression seal made on a ceramic component of the battery which separates an anode compartment from a cathode compartment of the battery.

  2. SIMPLIFIED SODIUM GRAPHITE REACTOR SYSTEM

    DOE Patents [OSTI]

    Dickinson, R.W.

    1963-03-01

    This patent relates to a nuclear power reactor comprising a reactor vessel, shielding means positioned at the top of said vessel, means sealing said reactor vessel to said shielding means, said vessel containing a quantity of sodium, a core tank, unclad graphite moderator disposed in said tank, means including a plurality of process tubes traversing said tank for isolating said graphite from said sodium, fuel elements positioned in said process tubes, said core tank being supported in spaced relation to the walls and bottom of said reactor vessel and below the level of said sodium, neutron shielding means positioned adjacent said core tank between said core tank and the walls of said vessel, said neutron shielding means defining an annuiar volume adjacent the inside wall of said reactor vessel, inlet plenum means below said core tank for providing a passage between said annular volume and said process tubes, heat exchanger means removably supported from the first-named shielding means and positioned in said annular volume, and means for circulating said sodium over said neutron shielding means down through said heat exchanger, across said inlet plenum and upward through said process tubes, said last-named means including electromagnetic pumps located outside said vessel and supported on said vessel wall between said heat exchanger means and said inlet plenum means. (AEC)

  3. Volume efficient sodium sulfur battery

    DOE Patents [OSTI]

    Mikkor, Mati

    1980-01-01

    In accordance with the teachings of this specification, a sodium sulfur battery is formed as follows. A plurality of box shaped sulfur electrodes are provided, the outer surfaces of which are defined by an electrolyte material. Each of the electrodes have length and width dimensions substantially greater than the thicknesses thereof as well as upwardly facing surface and a downwardly facing surface. An electrode structure is contained in each of the sulfur electrodes. A holding structure is provided for holding the plurality of sulfur electrodes in a stacked condition with the upwardly facing surface of one sulfur electrode in facing relationship to the downwardly facing surface of another sulfur electrode thereabove. A small thickness dimension separates each of the stacked electrodes thereby defining between each pair of sulfur electrodes a volume which receives the sodium reactant. A reservoir is provided for containing sodium. A manifold structure interconnects the volumes between the sulfur electrodes and the reservoir. A metering structure controls the flow of sodium between the reservoir and the manifold structure.

  4. Spray bottle apparatus with pressure multiplying pistons

    DOE Patents [OSTI]

    Moss, Owen R.; Gordon, Norman R.; DeFord, Henry S.

    1990-01-01

    The present invention comprises a spray bottle in which the pressure resulting from the gripping force applied by the user is amplified and this increased pressure used in generating a spray such as an aerosol or fluid stream. In its preferred embodiment, the invention includes a high pressure chamber and a corresponding piston which is operative for driving fluid out of this chamber at high pressure through a spray nozzle and a low pressure chamber and a corresponding piston which is acted upon the hydraulic pressure within the bottle resulting from the gripping force. The low pressure chamber and piston are of larger size than the high pressure chamber and piston. The pistons are rigidly connected so that the force created by the pressure acting on the piston in the low pressure chamber is transmitted to the piston in the high pressure chamber where it is applied over a more limited area thereby generating greater hydraulic pressure for use in forming the spray.

  5. Differential pressure pin discharge apparatus

    DOE Patents [OSTI]

    Oakley, D.J.

    1984-05-30

    Disclosed is a discharge assembly for allowing elongate pins to be discharged from an area of relatively low pressure to an area of relatively greater pressure. The discharge assembly includes a duck valve having a lip piece made of flexible material. The flexible lip piece responds to a fluctuating pressure created downstream by an aspirator. The aspirator reduces the downstream pressure sensed by the duck valve when the discharge assembly is in the open position. This allows elongate pins to be moved through the duck valve with no backflow because the aspirator pressure is less than the pressure in the low pressure area from which the pins originate. Closure of the assembly causes the aspirator static pressure to force the flexible duck valve lip piece into a tightly sealed position also preventing backflow. The discharge assembly can be easily controlled using a single control valve which blocks the flow of aspirator gas and closes the pins passageway extending through the assembly.

  6. Cast Stone Formulation At Higher Sodium Concentrations

    SciTech Connect (OSTI)

    Fox, K. M.; Edwards, T. A.; Roberts, K. B.

    2013-10-02

    A low temperature waste form known as Cast Stone is being considered to provide supplemental Low Activity Waste (LAW) immobilization capacity for the Hanford site. Formulation of Cast Stone at high sodium concentrations is of interest since a significant reduction in the necessary volume of Cast Stone and subsequent disposal costs could be achieved if an acceptable waste form can be produced with a high sodium molarity salt solution combined with a high water to premix (or dry blend) ratio. The objectives of this study were to evaluate the factors involved with increasing the sodium concentration in Cast Stone, including production and performance properties and the retention and release of specific components of interest. Three factors were identified for the experimental matrix: the concentration of sodium in the simulated salt solution, the water to premix ratio, and the blast furnace slag portion of the premix. The salt solution simulants used in this study were formulated to represent the overall average waste composition. The cement, blast furnace slag, and fly ash were sourced from a supplier in the Hanford area in order to be representative. The test mixes were prepared in the laboratory and fresh properties were measured. Fresh density increased with increasing sodium molarity and with decreasing water to premix ratio, as expected given the individual densities of these components. Rheology measurements showed that all of the test mixes produced very fluid slurries. The fresh density and rheology data are of potential value in designing a future Cast Stone production facility. Standing water and density gradient testing showed that settling is not of particular concern for the high sodium compositions studied. Heat of hydration measurements may provide some insight into the reactions that occur within the test mixes, which may in turn be related to the properties and performance of the waste form. These measurements showed that increased sodium

  7. Cast Stone Formulation At Higher Sodium Concentrations

    SciTech Connect (OSTI)

    Fox, K. M.; Roberts, K. A.; Edwards, T. B.

    2013-09-17

    A low temperature waste form known as Cast Stone is being considered to provide supplemental Low Activity Waste (LAW) immobilization capacity for the Hanford site. Formulation of Cast Stone at high sodium concentrations is of interest since a significant reduction in the necessary volume of Cast Stone and subsequent disposal costs could be achieved if an acceptable waste form can be produced with a high sodium molarity salt solution combined with a high water to premix (or dry blend) ratio. The objectives of this study were to evaluate the factors involved with increasing the sodium concentration in Cast Stone, including production and performance properties and the retention and release of specific components of interest. Three factors were identified for the experimental matrix: the concentration of sodium in the simulated salt solution, the water to premix ratio, and the blast furnace slag portion of the premix. The salt solution simulants used in this study were formulated to represent the overall average waste composition. The cement, blast furnace slag, and fly ash were sourced from a supplier in the Hanford area in order to be representative. The test mixes were prepared in the laboratory and fresh properties were measured. Fresh density increased with increasing sodium molarity and with decreasing water to premix ratio, as expected given the individual densities of these components. Rheology measurements showed that all of the test mixes produced very fluid slurries. The fresh density and rheology data are of potential value in designing a future Cast Stone production facility. Standing water and density gradient testing showed that settling is not of particular concern for the high sodium compositions studied. Heat of hydration measurements may provide some insight into the reactions that occur within the test mixes, which may in turn be related to the properties and performance of the waste form. These measurements showed that increased sodium

  8. Cast Stone Formulation At Higher Sodium Concentrations

    SciTech Connect (OSTI)

    Fox, K. M.; Roberts, K. A.; Edwards, T. B.

    2014-02-28

    A low temperature waste form known as Cast Stone is being considered to provide supplemental Low Activity Waste (LAW) immobilization capacity for the Hanford site. Formulation of Cast Stone at high sodium concentrations is of interest since a significant reduction in the necessary volume of Cast Stone and subsequent disposal costs could be achieved if an acceptable waste form can be produced with a high sodium molarity salt solution combined with a high water to premix (or dry blend) ratio. The objectives of this study were to evaluate the factors involved with increasing the sodium concentration in Cast Stone, including production and performance properties and the retention and release of specific components of interest. Three factors were identified for the experimental matrix: the concentration of sodium in the simulated salt solution, the water to premix ratio, and the blast furnace slag portion of the premix. The salt solution simulants used in this study were formulated to represent the overall average waste composition. The cement, blast furnace slag, and fly ash were sourced from a supplier in the Hanford area in order to be representative. The test mixes were prepared in the laboratory and fresh properties were measured. Fresh density increased with increasing sodium molarity and with decreasing water to premix ratio, as expected given the individual densities of these components. Rheology measurements showed that all of the test mixes produced very fluid slurries. The fresh density and rheology data are of potential value in designing a future Cast Stone production facility. Standing water and density gradient testing showed that settling is not of particular concern for the high sodium compositions studied. Heat of hydration measurements may provide some insight into the reactions that occur within the test mixes, which may in turn be related to the properties and performance of the waste form. These measurements showed that increased sodium

  9. Liquid sodium dip seal maintenance system

    DOE Patents [OSTI]

    Briggs, Richard L.; Meacham, Sterling A.

    1980-01-01

    A system for spraying liquid sodium onto impurities associated with liquid dip seals of nuclear reactors. The liquid sodium mixing with the impurities dissolves the impurities in the liquid sodium. The liquid sodium having dissolved and diluted the impurities carries the impurities away from the site thereby cleaning the liquid dip seal and surrounding area. The system also allows wetting of the metallic surfaces of the dip seal thereby reducing migration of radioactive particles across the wetted boundary.

  10. Protective tubes for sodium heated water tubes

    DOE Patents [OSTI]

    Essebaggers, Jan

    1979-01-01

    A heat exchanger in which water tubes are heated by liquid sodium which minimizes the results of accidental contact between the water and the sodium caused by failure of one or more of the water tubes. A cylindrical protective tube envelopes each water tube and the sodium flows axially in the annular spaces between the protective tubes and the water tubes.

  11. Thermophysical Properties of Sodium Nitrate and Sodium Chloride

    Office of Scientific and Technical Information (OSTI)

    The smaller the permeability, the more water is transferred into the saline environment. Effects of permeability on water flow are also complicated by effects of capillary pressure ...

  12. Separation of sodium-22 from irradiated targets

    DOE Patents [OSTI]

    Taylor, Wayne A.; Jamriska, David

    1996-01-01

    A process for selective separation of sodium-22 from an irradiated target including dissolving an irradiated target to form a first solution, contacting the first solution with hydrated antimony pentoxide to selectively separate sodium-22 from the first solution, separating the hydrated antimony pentoxide including the separated sodium-22 from the first solution, dissolving the hydrated antimony pentoxide including the separated sodium-22 in a mineral acid to form a second solution, and, separating the antimony from the sodium-22 in the second solution.

  13. Fire suppressing apparatus. [sodium fires

    DOE Patents [OSTI]

    Buttrey, K.E.

    1980-12-19

    Apparatus for smothering a liquid sodium fire comprises a pan, a perforated cover on the pan, and tubed depending from the cover and providing communication between the interior of the pan and the ambient atmosphere through the perforations in the cover. Liquid caught in the pan rises above the lower ends of the tubes and thus serves as a barrier which limits the amount of air entering the pan.

  14. Model test on underground coal gasification (UCG) with low-pressure fire seepage push-through. Part I: Test conditions and air fire seepage

    SciTech Connect (OSTI)

    Yang, L.H.

    2008-07-01

    The technology of a pushing-through gallery with oxygen-enriched fire-seepage combustion was studied during shaft-free UCG in this article, and the main experiment parameters were probed. The test results were analyzed in depth. The patterns of variation and development were pointed out for the fire source moving speed, temperature field, leakage rate, the expanding diameter for the gasification gallery, and blasting pressure. Test results showed that, with the increase in the wind-blasting volume, the moving velocity for the fire source speeded up, and the average temperature for the gallery continuously rose. Under the condition of oxygen-enriched air blasting, when O{sub 2} contents stood at 90%, the moving speed for the fire source was 4-5 times that of air blasting. In the push-through process, the average leakage rate for the blasting was 82.23%, with the average discharge volume of 3.43 m{sup 3}/h and average gallery diameter of 7.87 cm. With the proceeding of firepower seepage, the extent of dropping for the leakage rate increased rapidly, and the drop rate for the blasting pressure gradually heightened.

  15. Numerical investigation of the effect of driving voltage pulse shapes on the characteristics of low-pressure argon dielectric barrier discharge

    SciTech Connect (OSTI)

    Eslami, E. Barjasteh, A.; Morshedian, N.

    2015-06-15

    In this work, we numerically compare the effect of a sinusoidal, triangular, and rectangular pulsed voltage profile on the calculated particle production, electric current, and gas voltage in a dielectric barrier discharge. The total argon gas pressure of 400 Pa, the distance between dielectrics of 5 mm, the dielectric thickness of 0.7 mm, and the temperature of T = 300 K were considered as input parameters. The different driving voltage pulse shapes (triangular, rectangular, and sinusoidal) are considered as applied voltage with a frequency of 7 kHz and an amplitude of 700 V peak to peak. It is shown that applying a rectangular voltage, as compared with a sinusoidal or triangle voltage, increases the current peak, while the peak width is decreased. Higher current density is related to high production of charged particles, which leads to the generation of some highly active species, such as Ar* (4s level), and Ar** (4p level) in the gap.

  16. Ion Recognition Approach to Volume Reduction of Alkaline Tank Waste by Separation and Recycle of Sodium Hydroxide and Sodium Nitrate

    SciTech Connect (OSTI)

    Moyer, Bruce A.; Marchand, Alan P.; Bonnesen, Peter V.; Bryan, Jeffrey C.; Haverlock, Tamara J.

    2002-03-30

    This research has focused on new liquid-liquid extraction chemistry applicable to separation of major sodium salts from alkaline tank waste. It was the overall goal to provide the scientific foundation upon which the feasibility of liquid-liquid extraction chemistry for bulk reduction of the volume of tank waste can be evaluated. Sodium hydroxide represented the initial test case and primary focus. It is a primary component of the waste1 and has the most value for recycle. A full explanation of the relevance of this research to USDOE Environmental Management needs will be given in the Relevance, Impact, and Technology Transfer section below. It should be noted that this effort was predicated on the need for sodium removal primarily from low-activity waste, whereas evolving needs have shifted attention to volume reduction of the high-activity waste. The results of the research to date apply to both applications, though treatment of high-activity wastes raises new questions that will be addressed in the renewal period. Toward understanding the extractive chemistry of sodium hydroxide and other sodium salts, it was the intent to identify candidate extractants and determine their applicable basic properties regarding selectivity, efficiency, speciation, and structure. A hierarchical strategy was to be employed in which the type of liquid-liquid-extraction system varied in sophistication from simple, single-component solvents to solvents containing designer host molecules. As an aid in directing this investigation toward addressing the fundamental questions having the most value, a conceptualization of an ideal process was advanced. Accordingly, achieving adequate selectivity for sodium hydroxide represented a primary goal, but this result is worthwhile for waste applications only if certain conditions are met.

  17. Pressure sensor

    SciTech Connect (OSTI)

    Mee, David K.; Ripley, Edward B.; Nienstedt, Zachary C.; Nienstedt, Alex W.; Howell, Jr., Layton N.

    2015-09-29

    Disclosed is a passive, in-situ pressure sensor. The sensor includes a sensing element having a ferromagnetic metal and a tension inducing mechanism coupled to the ferromagnetic metal. The tension inducing mechanism is operable to change a tensile stress upon the ferromagnetic metal based on a change in pressure in the sensing element. Changes in pressure are detected based on changes in the magnetic switching characteristics of the ferromagnetic metal when subjected to an alternating magnetic field caused by the change in the tensile stress. The sensing element is embeddable in a closed system for detecting pressure changes without the need for any penetrations of the system for power or data acquisition by detecting changes in the magnetic switching characteristics of the ferromagnetic metal caused by the tensile stress.

  18. Pressure regulator

    DOE Patents [OSTI]

    Ebeling, Jr., Robert W.; Weaver, Robert B.

    1979-01-01

    The pressure within a pressurized flow reactor operated under harsh environmental conditions is controlled by establishing and maintaining a fluidized bed of uniformly sized granular material of selected density by passing the gas from the reactor upwardly therethrough at a rate sufficient to fluidize the bed and varying the height of the bed by adding granular material thereto or removing granular material therefrom to adjust the backpressure on the flow reactor.

  19. PRESSURE TRANSDUCER

    DOE Patents [OSTI]

    Sander, H.H.

    1959-10-01

    A pressure or mechanical force transducer particularly adaptable to miniature telemetering systems is described. Basically the device consists of a transistor located within a magnetic field adapted to change in response to mechanical force. The conduction characteristics of the transistor in turn vary proportionally with changes in the magnetic flux across the transistor such that the output (either frequency of amplitude) of the transistor circuit is proportional to mechanical force or pressure.

  20. Pump tank divider plate for sump suction sodium pumps

    DOE Patents [OSTI]

    George, John A.; Nixon, Donald R.

    1977-01-01

    A circular plate extends across the diameter of "sump suction" pump, with a close clearance between the edge of the plate and the wall of the pump tank. The plate is located above the pump impeller, inlet and outlet flow nozzles but below the sodium free surface and effectively divides the pump tank into two separate chambers. On change of pump speed, the close fitting flow restriction plate limits the rate of flow into or out of the upper chamber, thereby minimizing the rate of level change in the tank and permitting time for the pump cover gas pressure to be varied to maintain an essentially constant level.

  1. Planar high density sodium battery

    DOE Patents [OSTI]

    Lemmon, John P.; Meinhardt, Kerry D.

    2016-03-01

    A method of making a molten sodium battery is disclosed. A first metallic interconnect frame having a first interconnect vent hole is provided. A second metallic interconnect frame having a second interconnect vent hole is also provided. An electrolyte plate having a cathode vent hole and an anode vent hole is interposed between the metallic interconnect frames. The metallic interconnect frames and the electrolyte plate are sealed thereby forming gaseous communication between an anode chamber through the anode vent hole and gaseous communication between a cathode chamber through the cathode vent hole.

  2. Solvent-refined-coal (SRC) process. Determination of trace hydrocarbon, sulfur, and nitrogen compounds in SRC-II process development Unit P-99 gas streams. [Impure hydrogen in recycle gas and low pressure gas processing

    SciTech Connect (OSTI)

    Gray, J.A.; Galli, R.D.; McCracken, J.H.

    1982-02-01

    A knowledge of the identity and concentration of trace hydrocarbon, sulfur, and nitrogen compounds in the various gas streams of the SRC-II Coal Liquefaction Process is needed in order to design the recycle gas purification and low pressure gas processing systems in large-scale plants. This report discusses the results of an experimental study to identify and quantify trace compounds in the various high and low pressure gas streams of SRC-II Process Development Unit P-99. A capillary column trace hydrocarbon analysis has been developed which can quantify 41 hydrocarbons from methane to xylenes in SRC-II gas streams. With more work a number of other hydrocarbons could be quantified. A fixed gas analysis was also developed which can be integrated with the hydrocarbon analysis to yield a complete stream analysis. A gas chromatographic procedure using a flame photometric detector was developed for trace sulfur compounds, and six sulfur compounds were identified and quantified. A chemiluminescence method was developed for determination of NO and NO/sub 2/ down to 10 ppB in concentration. A gas chromatographic procedure using an electron capture detector was developed for HCN analysis down to 5 ppM. Drager tube analyses gave semiquantitative data on HCl and NH/sub 3/ content of the gas streams.

  3. Apparatus for detecting leakage of liquid sodium

    DOE Patents [OSTI]

    Himeno, Yoshiaki

    1978-01-01

    An apparatus for detecting the leakage of liquid sodium includes a cable-like sensor adapted to be secured to a wall of piping or other equipment having sodium on the opposite side of the wall, and the sensor includes a core wire electrically connected to the wall through a leak current detector and a power source. An accidental leakage of the liquid sodium causes the corrosion of a metallic layer and an insulative layer of the sensor by products resulted from a reaction of sodium with water or oxygen in the atmospheric air so as to decrease the resistance between the core wire and the wall. Thus, the leakage is detected as an increase in the leaking electrical current. The apparatus is especially adapted for use in detecting the leakage of liquid sodium from sodium-conveying pipes or equipment in a fast breeder reactor.

  4. Independent Oversight Review, Sodium Bearing Waste Treatment...

    Office of Environmental Management (EM)

    This report documents the results of an independent review of the Sodium Bearing Waste Treatment Project-Integrated Waste Treatment Unit Federal Operational Readiness Review. ...

  5. Sodium-layer laser guide stars

    SciTech Connect (OSTI)

    Friedman, H.W.

    1993-08-03

    The requirements and design of a laser system to generate a sodium- layer beacon is presented. Early results of photometry and wavefront sensing are given.

  6. Independent Oversight Assessment, Idaho Cleanup Project Sodium...

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

    Waste Treatment Project - November 2012 November 2012 Assessment of Nuclear Safety Culture at the Idaho Cleanup Project Sodium Bearing Waste Treatment Project This report...

  7. TOXICOLOGICAL AND STRUCTURAL CONSEQUENCES FROM SODIUM-WATER REACTION IN CELL CONTAINING THE SECONDARY SODIUM TANK

    SciTech Connect (OSTI)

    MARUSICH RM

    2008-06-25

    The analysis will show the consequences should the solid sodium in the Secondary Sodium Tank react with a presumed layer of water in the cell. The Peer Review Checklist is attached.

  8. Final report-passive safety optimization in liquid sodium-cooled reactors.

    SciTech Connect (OSTI)

    Cahalana, J. E.; Hahn, D.; Nuclear Engineering Division; Korea Atomic Energy Research Inst.

    2007-08-13

    Implications of Advanced Technology Power Conversion and Design Innovations and Simplifications: Investigations of supercritical CO{sub 2} gas turbine Brayton cycles coupled to the sodium-cooled reactors and innovative concepts for sodium-to-CO{sub 2} heat exchangers were performed to discover new designs for high efficiency electricity production. The objective of the analyses was to characterize the design and safety performance of equipment needed to implement the new power cycle. The project included considerations of heat transfer and power conversion systems arrangements and evaluations of systems performance. Task 4--Post Accident Heat Removal and In-Vessel Retention: Test plans were developed to evaluate (1) freezing and plugging of molten metallic fuel in subassembly geometry, (2) retention of metallic fuel core melt debris within reactor vessel structures, and (3) consequences of intermixing of high pressure CO{sub 2} and sodium. The objective of the test plan development was to provide planning for measurements of data needed to characterize the consequences of very low probability accident sequences unique to metallic fuel and CO{sub 2} Brayton power cycles. The project produced three test plans ready for execution.

  9. The vapor pressures of explosives

    SciTech Connect (OSTI)

    Ewing, Robert G.; Waltman, Melanie J.; Atkinson, David A.; Grate, Jay W.; Hotchkiss, Peter

    2013-01-05

    The vapor pressures of many explosive compounds are extremely low and thus determining accurate values proves difficult. Many researchers, using a variety of methods, have measured and reported the vapor pressures of explosives compounds at single temperatures, or as a function of temperature using vapor pressure equations. There are large variations in reported vapor pressures for many of these compounds, and some errors exist within individual papers. This article provides a review of explosive vapor pressures and describes the methods used to determine them. We have compiled primary vapor pressure relationships traceable to the original citations and include the temperature ranges for which they have been determined. Corrected values are reported as needed and described in the text. In addition, after critically examining the available data, we calculate and tabulate vapor pressures at 25 C.

  10. Pressure sensor for high-temperature liquids

    DOE Patents [OSTI]

    Forster, George A.

    1978-01-01

    A pressure sensor for use in measuring pressures in liquid at high temperatures, especially such as liquid sodium or liquid potassium, comprises a soft diaphragm in contact with the liquid. The soft diaphragm is coupled mechanically to a stiff diaphragm. Pressure is measured by measuring the displacment of both diaphragms, typically by measuring the capacitance between the stiff diaphragm and a fixed plate when the stiff diaphragm is deflected in response to the measured pressure through mechanical coupling from the soft diaphragm. Absolute calibration is achieved by admitting gas under pressure to the region between diaphragms and to the region between the stiff diaphragm and the fixed plate, breaking the coupling between the soft and stiff diaphragms. The apparatus can be calibrated rapidly and absolutely.